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Sample records for aggregates rock and stone

  1. Geo-Engineering Evaluation of Rock Masses for Crushed Rock and Cut Stones in Khartoum State, Sudan

    Science.gov (United States)

    Kheirelseed, E. E.; Ming, T. H.; Abdalla, S. B.

    The purpose of this study is to find artificial coarse aggregates and cut stones around Khartoum. To meat the objectives of the study, data from both field and laboratory are collected. The field data includes geological investigations based on different methods and samples collection, whereas the laboratory tests consists of specific gravity, water absorption, impact value, crushing value, Los Angeles abrasion, soundness tests. The field and laboratory results were weighed and compiled together to reveal the engineering performance of the different rock masses in term of cut stone and crushed aggregates. The results show that most of the examined rock masses are suitable for crushing, building and dressed stones. For decorative slabs only foliated granite and syenite masses can be used.

  2. Artificial porous stone from of ornamental rock waste adaptable for civil construction and heritage restoration

    International Nuclear Information System (INIS)

    Durán Suárez, J.A.; García Casco, A.

    2017-01-01

    The technique of volumetric reintegration in severely deteriorated stone materials is of major importance for the restoration of architectural heritage. In using mortars for restoration it is important to control aspects such as the colour and textural similarity in relation to the adjacent stone, minor or equal strength and equal or greater porosity/permeability with respect to the original stone. This latter aspect is of particular complexity because the percentage distribution of pore-size ranges should not differ from that of the original stone material. The invention patent (with numbers of publication ES2187245 A1 and B1 16. 06. 2004), owned by the University of Granada, allows the production of excellent porous stones for decorative work in construction and mortar for restoration of stone materials with controlled porosity. Both materials consist of ornamental rock waste, so that a particular recycling purpose is given to this type of material which is difficult to reuse. In this paper we present the manufacturing process of these artificial stones and porous mortars with decorative and restorative purposes, from the controlled mixture of aggregates of ornamental rocks, organic and inorganic binders and generators of porosity. Once the curing and hardening has been done it is worth noting that one of the most important aspects of the product is the generation of a complex connected porous system as a result of the incorporation of crushed expanded polystyrene, which is activated after hardening through the application of organic solvents. [es

  3. Evaluation of physical and mechanical properties of quarry stones in the southern Republic of Benin

    Directory of Open Access Journals (Sweden)

    Bouraima Mouhamed Bayane

    2017-05-01

    Full Text Available Engineering properties of stones have a crucial importance when they are used for civil engineering works. In this study, the suitability of rocks blocks or stones as a construction material is established. Cove and Dan cities surroundings in the southern part of Zou Province have large blocks and aggregates quarries operated recently. In this study, laboratory tests were carried out to investigate the performance of rocks blocks and aggregates quarried in the region. For this purpose of the study, three wooden containers with rocks blocks and aggregates samples were collected from three different quarries, and so, laboratory tests including particle density and water absorption test, resistance to wear, magnesium sulfate test, compressive strength and methylene blue absorption test were performed in accordance with the international standards to explore the quality of stones to be used for modern construction. Concluding that rocks blocks and aggregates satisfy the relevant regulation (that is, a norm, European standard.

  4. Captured in Stone: Women in the Rock Art of Canyon de Chelly.

    Science.gov (United States)

    Travis, Tara

    1997-01-01

    Describes the pictographs (painted images on stone) and petroglyphs (pecked images on stone) found in the Canyon de Chelly National Monument in Arizona. Canyon de Chelly includes one of the largest concentrations of American Indian rock art in the southwest. Discusses the depiction of women in these images. (MJP)

  5. Dielectric non destructive testing for rock characterization in natural stone industry and cultural heritage

    Science.gov (United States)

    López-Buendía, Angel M.; García-Baños, Beatriz; Mar Urquiola, M.; Gutiérrez, José D.; Catalá-Civera, José M.

    2016-04-01

    Dielectric constant measurement has been used in rocks characterization, mainly for exploration objective in geophysics, particularly related to ground penetration radar characterization in ranges of 10 MHz to 1 GHz. However, few data have been collected for loss factor. Complex permittivity (dielectric constant and loss factor) characterization in rock provide information about mineralogical composition as well as other petrophysic parameters related to the quality, such as fabric parameters, mineralogical distribution, humidity. A study was performed in the frequency of 2,45GHz by using a portable kit for dielectric device based on an open coaxial probe. In situ measurements were made of natural stone marble and granite on selected industrial slabs and building stone. A mapping of their complex permittivity was performed and evaluated, and variations in composition and textures were identified, showing the variability with the mineral composition, metal ore minerals content and fabric. Dielectric constant was a parameter more sensible to rock forming minerals composition, particularly in granites for QAPF-composition (quartz-alkali feldspar-plagioclases-feldspathoids) and in marbles for calcite-dolomite-silicates. Loss factor shown a high sensibility to fabric and minerals of alteration. Results showed that the dielectric properties can be used as a powerful tool for petrographic characterization of building stones in two areas of application: a) in cultural heritage diagnosis to estimate the quality and alteration of the stone, an b) in industrial application for quality control and industrial microwave processing.

  6. Strides in Preservation of Malawi's Natural Stone

    Science.gov (United States)

    Kamanga, Tamara; Chisenga, Chikondi; Katonda, Vincent

    2017-04-01

    The geology of Malawi is broadly grouped into four main lithological units that is the Basement Complex, the Karoo Super group, Tertiary to Quaternary sedimentary deposits and the Chilwa Alkaline province. The basement complex rocks cover much of the country and range in age from late Precambrian to early Paleozoic. They have been affected by three major phases of deformation and metamorphism that is the Irumide, Ubendian and The Pan-African. These rocks comprise gneisses, granulites and schists with associated mafic, ultramafic, syenites and granite rocks. The Karoo System sedimentary rocks range in age from Permian to lower Jurassic and are mainly restricted to two areas in the extreme North and extreme Alkaline Province - late Jurassic to Cretaceous in age, preceded by upper Karoo Dolerite dyke swarms and basaltic lavas, have been intruded into the Basement Complex gneisses of southern Malawi. Malawi is endowed with different types of natural stone deposits most of which remain unexploited and explored. Over twenty quarry operators supply quarry stone for road and building construction in Malawi. Hundreds of artisanal workers continue to supply aggregate stones within and on the outskirts of urban areas. Ornamental stones and granitic dimension stones are also quarried, but in insignificant volumes. In Northern Malawi, there are several granite deposits including the Nyika, which is the largest single outcrop occupying approximately 260.5 km2 , Mtwalo Amazonite an opaque to translucent bluish -green variety of microcline feldspar that occurs in alkali granites and pegmatite, the Ilomba granite (sodalite) occurring in small areas within biotite; apatite, plagioclase and calcite. In the Center, there are the Dzalanyama granites, and the Sani granites. In the South, there are the Mangochi granites. Dolerite and gabbroic rocks spread across the country, treading as black granites. Malawi is also endowed with many deposits of marble. A variety of other igneous

  7. Analysis of Precious Stones Deposited in Various Rock Samples of Mogok Region by energy dispersive X-ray Fluorescence Spectrometry

    International Nuclear Information System (INIS)

    Kyi Kyi San; Soe Lwin; Win Win Thar; Sein Htoon

    2004-06-01

    The analysis of precious stones deposited in various rock samples of Mogok region were investigated by the energy dispersive x-ray fluorescence technique. The x-ray machine with Rh target was used to excite the characteristic x-ray from the sample. X-rays emitted from the sample were measured by a high resolution, cooled Si (Li) detector. The calibration was made by the measurement of minerals which composed in each kind of precious stones. The kind of precious stone deposited in the rocks sample was determined by the measurement of minerals from the rock samples compared with those obtained from each kind of precious stones

  8. Characterization and testing of rock aggregates of the Santa Marta Batholith, (Colombia

    Directory of Open Access Journals (Sweden)

    Nancy Paola Figueroa Madero

    2014-12-01

    Full Text Available Aggregates of intrusive rocks are the major source of crushed fine and coarse aggregates for use in concrete in several countries and they have to meet a number of specifications relating to strength and durability. This research reports the evaluation of aggregates of granitoids and associated rocks of Santa Marta Batholith, Sierra Nevada de Santa Marta Massif, Colombia, based on petrographic analysis and mechanical and chemical acceptance tests. The strength and durability of a particular rock type depends on its intrinsic characteristic, thus petrographic analysis is very important to understand its mechanical and chemical properties. Numerous standard tests used to ensure aggregates meet the appropriate specifications; however, petrographic analysis represents the most valuable test for predicting the overall performance of concrete aggregates in any control test. Aggregates were analyzed to determine their petrographic, physical, mechanical and chemical properties. Samples were categorized as hornblendite, gabbro, quartzmonzodiorite, monzodiorite and monzonite groups. Among these, of the quartzmonzodiorite was the dominant group. Specific gravity indicates values in the range 2673-2956kg/m3. Water absorption values are in the range 0.908-1.194%. Aggregate impact values of samples (37.82 to 61.36% showed good soundness only for one of the aggregates, which are considered acceptable for use in the preparation of a good quality concrete. Values of Methylene Blue Adsorption reveal the organic matter content is below the threshold. Magnesium sulphate values ranged between 0.11 and 4.75% suggesting good resistance against chemical atmospheric agents. The compressive strength test shows values in the range 35.22-59.45MPa indicating that the geomechanical behavior of rock cylinders is satisfactory. The geomechanical behavior of rock tablets under flexion is also satisfactory for SMA-2 sample (16.53MPa, although not for SMA-6 and SMA-8 samples

  9. Geotechnical characteristics and stability analysis of rock-soil aggregate slope at the Gushui Hydropower Station, southwest China.

    Science.gov (United States)

    Zhou, Jia-wen; Shi, Chong; Xu, Fu-gang

    2013-01-01

    Two important features of the high slopes at Gushui Hydropower Station are layered accumulations (rock-soil aggregate) and multilevel toppling failures of plate rock masses; the Gendakan slope is selected for case study in this paper. Geological processes of the layered accumulation of rock and soil particles are carried out by the movement of water flow; the main reasons for the toppling failure of plate rock masses are the increasing weight of the upper rock-soil aggregate and mountain erosion by river water. Indoor triaxial compression test results show that, the cohesion and friction angle of the rock-soil aggregate decreased with the increasing water content; the cohesion and the friction angle for natural rock-soil aggregate are 57.7 kPa and 31.3° and 26.1 kPa and 29.1° for saturated rock-soil aggregate, respectively. The deformation and failure mechanism of the rock-soil aggregate slope is a progressive process, and local landslides will occur step by step. Three-dimensional limit equilibrium analysis results show that the minimum safety factor of Gendakan slope is 0.953 when the rock-soil aggregate is saturated, and small scale of landslide will happen at the lower slope.

  10. ROCK and PRK-2 Mediate the Inhibitory Effect of Y-27632 on Polyglutamine Aggregation

    Science.gov (United States)

    Shao, Jieya; Welch, William J.; Diamond, Marc I.

    2009-01-01

    Polyglutamine expansion in huntingtin (Htt) and the androgen receptor (AR) causes untreatable neurodegenerative diseases. Y-27632, a therapeutic lead, reduces Htt and AR aggregation in cultured cells, and Htt-induced neurodegeneration in Drosophila. Y-27632 inhibits both Rho-associated kinases ROCK and PRK-2, making its precise intracellular target uncertain. Over-expression of either kinase increases Htt and AR aggregation. Three ROCK inhibitors (Y-27632, H-1077, HA-1152), and a specific ROCK inhibitory peptide reduce polyglutamine protein aggregation, as does knockdown of ROCK or PRK-2 by RNAi. RNAi also indicates that each kinase is required for the inhibitory effects of Y-27632 to manifest fully. These two actin regulatory kinases are thus involved in polyglutamine aggregation, and their simultaneous inhibition may be an important therapeutic goal. PMID:18423405

  11. Properties Improvement of Cast Stone Produced Using Recycled Glass Waste and Lightweight Aggregates

    Directory of Open Access Journals (Sweden)

    Elham Abd AL-Majeed

    2018-01-01

    Full Text Available Cast stone (CS is a form of pre-cast concrete widely, used in architectural applications for decorating and building face in place of natural stone due its superior features. The present study was an attempt in using of local lightweight aggregate materials (LWAM as an alternative to percentage of coarse aggregate, and glass wastes as alternatives to percentages of fine aggregate in cast stone normal mixtures with white cement and plasticizer admixture. The CS products were cured after 24 hrs using of two different processes: water curing (at 23 C° for 3 days and steam curing (at 60 C° for 14 hrs. Then the products were characterized by tests of compressive strength, design, absorption, flexure strength and liner drying shrinkage. The addition of alternative materials was done by trial mixes (M0-M3 through 3 groups (A, B, and C according to standards. Group A: design of reference mixtures of CS with compressive strength of 46.3 MPa and the absorption of 6.19%, Group B: design of mixtures containing 50% LWA were 16% lighter than those of Group A with compressive strength of 43.6 MPa and 11% improvement in the absorption, Group C: design of mixtures containing (50 and 75% glass waste with compressive strength of (47.5-44.3 MPa and the absorption of (5.3-4.7%, respectively. The modified steam curing process (curing after 24 hrs casting done in this study could prove its effectiveness in the achievement of the required compressive strength in comparison with the normal process (direct curing after casting due to the effect of such new process in providing the more uniform distribution of the cement gel with good physical properties. Results from the flexural strength test could prove the achievement of the required levels (6.9 – 6.3 at 50 – 75% glass waste addition recorded in the standard.

  12. Natural radioactivity in some rocks employed as dimension and decorative stones in the Nigerian building industry.

    Science.gov (United States)

    Tubosun, I A; Tchokossa, P; Balogun, F A; Fasasi, M K; Ocan, O; Adesanmi, C A

    2013-12-01

    The natural radioactivity in some selected granites and allied rocks from the Basement Complex of Nigeria for use as dimension/decorative stones was measured by gamma-ray spectrometry. The average activity concentrations observed for the selected rock samples range from 9 to 124 Bq kg⁻¹; 13 to 60 Bq kg⁻¹ and 1360 to 2326 Bq kg⁻¹ for ²²⁶Ra, ²³²Th and ⁴⁰K, respectively. The mean radiological hazard indices were 121.62 nGy h⁻¹; 239.73 Bq kg⁻¹; 0.65 Bq kg⁻¹ and 0.77 Bq kg⁻¹ for the absorbed dose rate, radium equivalent, external hazard and internal hazard, respectively. The results obtained were examined on the basis of existing International recommended limits and compared with data on similar rocks from other parts of the world. The values obtained for the rocks, except one, were found to be lower than the values recommended for building materials, and the rocks are considered safe for use as decorative stones as defined by OECD criteria (NEA-OCED Nuclear Energy Agency Dose Constraints in Optimisation of Occupational Radiological Protection Report by NEA Group Experts, OCED, France (2011)). Results highlight the fact that, despite meeting certain suitability criteria such as colour, texture, etc., the radioactivity content of the rocks is another factor of importance for their continued application in the human environment/building industry.

  13. Influence of mesostasis in volcanic rocks on the alkali-aggregate reaction

    KAUST Repository

    Tiecher, Francieli

    2012-11-01

    Mesostasis material present in the interstices of volcanic rocks is the main cause of the alkali-aggregate reaction (AAR) in concretes made with these rock aggregates. Mesostasis often is referred to as volcanic glass, because it has amorphous features when analyzed by optical microscopy. However, this study demonstrates that mesostasis in the interstitials of volcanic rocks most often consists of micro to cryptocrystalline mineral phases of quartz, feldspars, and clays. Mesostasis has been identified as having different characteristics, and, thus, this new characterization calls for a re-evaluation of their influence on the reactivity of the volcanic rocks. The main purpose of this study is to correlate the characteristics of mesostasis with the AAR in mortar bars containing basalts and rhyolites. © 2012 Elsevier Ltd. All rights reserved.

  14. Influence of mesostasis in volcanic rocks on the alkali-aggregate reaction

    KAUST Repository

    Tiecher, Francieli; Dal Molin, Denise Carpena Coitinho; Gomes, Má rcia Elisa Boscato; Hasparyk, Nicole Pagan; Monteiro, Paulo José Meleragno

    2012-01-01

    Mesostasis material present in the interstices of volcanic rocks is the main cause of the alkali-aggregate reaction (AAR) in concretes made with these rock aggregates. Mesostasis often is referred to as volcanic glass, because it has amorphous features when analyzed by optical microscopy. However, this study demonstrates that mesostasis in the interstitials of volcanic rocks most often consists of micro to cryptocrystalline mineral phases of quartz, feldspars, and clays. Mesostasis has been identified as having different characteristics, and, thus, this new characterization calls for a re-evaluation of their influence on the reactivity of the volcanic rocks. The main purpose of this study is to correlate the characteristics of mesostasis with the AAR in mortar bars containing basalts and rhyolites. © 2012 Elsevier Ltd. All rights reserved.

  15. Investigation of intact rock geomechanical parameters' effects on commercial blocks' productivity within stone reserves: A case history of some quarries in Isfahan, Iran

    Science.gov (United States)

    Yarahmadi, Reza; Bagherpour, Raheb; Tabaei, Morteza; Sousa, Luis M. O.

    2017-10-01

    One of the common methods to determine commercial blocks productivity (CBP) in reserves of dimension stone is through the study of the discontinuities' network. However, this determination remains a difficult task due to geographical heterogeneity and lack of access to all reserves' formations. This study presents a new method based on various geomechanical tests performed on intact rocks that assessed the CBP of a dimension stones' rock mass. Assuming that a dimension stone's rock mass comprised a large block of an intact rock, due to tectonics, the geomechanical properties of this block had direct effects on the discontinuities created within it. Therefore, the geomechanical properties of the intact rock may be related to the CBP of a stone reserve. Based on this factor, this study explored the relationship among some geomechanical properties, including failure angle, uniaxial compressive strength, and modulus of elasticity, and CBP by using data acquired from 21 dimension stone quarries consisting of travertine, marble, and onyx groups. According to the results obtained from the analysis of the Isfahan province's Iranian quarries, failure angle was not highly related to the reserve's CBP. In marble quarries, CBP may decrease, if the compressive strength of an intact rock exceeds 60 MPa. Among the studied parameters, the saturated-to-dry ratio's modulus of elasticity had the greatest relationship to the CBP. Generally, the presented diagrams displayed that the correlation between geomechanical properties and the CBP were an appropriate guide in determining the potential cost-effectiveness of a accessing a particular rock reserve during the early exploration phase.

  16. Provenance analysis of Roman stone artefacts from sedimentary rocks from the archaeological site near Mošnje, NW Slovenia

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    Snježana Miletić

    2016-08-01

    Full Text Available This study deals with the macroscopic and microfacies characterisation of Roman stone artefacts excavated in 2006 from a Roman villa rustica near Mošnje (NW Slovenia with the aim of defiing their provenance. A total of 28 representative fids (querns, mortars, whetstones, tooled and rounded stones, a fragment of stone slab, mosaic tesserae and two architectural elements - one with a relief made of clastic and carbonate sedimentary rocks were examined. Comparison was made with rock samples taken from quarries and gravel bars close to the archaeological site, as well as from larger distance to the site. The majority of artefact sampled is composed of Upper Palaeozoic quartz sandstones, which are found as pebbles in gravel bars close to the archaeological site; while 2 samples were from Quaternary coarse grained clastic rocks which can be found in local glacio-flvial sediments. Other fids were made of four different Mesozoic shallow-water limestones which outcrop in different areas of Central and SW Slovenia. The nearest Lower Jurassic biopelmicritic limestones are found at the western periphery of Ljubljana in Podutik. Cretaceous miliolid limestones and biocalcarenitic limestones with rudists are common in the successions of the Dinaric Carbonate Platform in SW Slovenia (for example, on the Trieste-Komen Plateau, NE Italy and SW Croatia. This indicates that the limestones for architectural elements, stone mortars and tesserae were brought to Mošnje from distant locations. Smaller stone tools are likely to have been made at the location of the archaeological site from material gathered locally, mostly pebbles from clastic rocks, which were accessible and suitable for tooling.

  17. Performance Evaluation of Stone Mastic Asphalt and Hot Mix Asphalt Mixtures Containing Recycled Concrete Aggregate

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    Mohammad Saeed Pourtahmasb

    2014-01-01

    Full Text Available Environmental and economic considerations have encouraged civil engineers to find ways to reuse recycled materials in new constructions. The current paper presents an experimental research on the possibility of utilizing recycled concrete aggregates (RCA in stone mastic asphalt (SMA and hot mix asphalt (HMA mixtures. Three categories of RCA in various percentages were mixed with virgin granite aggregates to produce SMA and HMA specimens. The obtained results indicated that, regardless of the RCA particular sizes, the use of RCA to replace virgin aggregates increased the needed binder content in the asphalt mixtures. Moreover, it was found that even though the volumetric and mechanical properties of the asphalt mixtures are highly affected by the sizes and percentages of the RCA but, based on the demands of the project and traffic volume, utilizing specific amounts of RCA in both types of mixtures could easily satisfy the standard requirements.

  18. Predicting Los Angeles abrasion loss of rock aggregates from ...

    Indian Academy of Sciences (India)

    WINTEC

    For this reason, to investigate the possibility of predicting the Los Angeles ... Different rocks have extensively been used as an aggregate .... men weight to the specimen volume. .... thesis is rejected and that there is a real relation between.

  19. Endolithic phototrophs in built and natural stone.

    Science.gov (United States)

    Gaylarde, Christine C; Gaylarde, Peter M; Neilan, Brett A

    2012-08-01

    Lichens, algae and cyanobacteria have been detected growing endolithically in natural rock and in stone buildings in various countries of Australasia, Europe and Latin America. Previously these organisms had mainly been described in natural carbonaceous rocks in aquatic environments, with some reports in siliceous rocks, principally from extremophilic regions. Using various culture and microscopy methods, we have detected endoliths in siliceous stone, both natural and cut, in humid temperate and subtropical climates. Such endolithic growth leads to degradation of the stone structure, not only by mechanical means, but also by metabolites liberated by the cells. Using in vitro culture, transmission, optical and fluorescence microscopy, and confocal laser scanning microscopy, both coccoid and filamentous cyanobacteria and algae, including Cyanidiales, have been identified growing endolithically in the facades of historic buildings built from limestone, sandstone, granite, basalt and soapstone, as well as in some natural rocks. Numerically, the most abundant are small, single-celled, colonial cyanobacteria. These small phototrophs are difficult to detect by standard microscope techniques and some of these species have not been previously reported within stone.

  20. Effect of rock fragment embedding on the aeolian deposition of dust on stone-covered surfaces

    NARCIS (Netherlands)

    Goossens, D.

    2005-01-01

    Many stone-covered surfaces on Earth are subject to aeolian deposition of atmospheric dust. This study investigates how the deposition of dust is affected when rock fragments become gradually more embedded in the ground or, inversely, become more concentrated on the surface. Experiments were

  1. Effect of palm oil fuel ash on compressive strength of palm oil boiler stone lightweight aggregate concrete

    Science.gov (United States)

    Muthusamy, K.; Zamri, N. A.; Kusbiantoro, A.; Lim, N. H. A. S.; Ariffin, M. A. Mohd

    2018-04-01

    Both palm oil fuel ash (POFA) and palm oil boiler stone (POBS) are by-products which has been continuously generated by local palm oil mill in large amount. Both by products is usually disposed as profitless waste and considered as nuisance to environment. The present research investigates the workability and compressive strength performance of lightweight aggregate concrete (LWAC) made of palm oil boiler stone (POBS) known as palm oil boiler stone lightweight aggregate concrete (POBS LWAC) containing various content of palm oil fuel ash. The control specimen that is POBS LWAC of grade 60 were produced using 100% OPC. Then, another 4 mixes were prepared by varying the POFA percentage from 10%, 20%, 30% and 40% by weight of cement. Fresh mixes were subjected to slump test to determine its workability before casted in form of cubes. Then, all specimens were subjected to water curing up to 28 days and then tested for its compressive strength. It was found out that utilizing of optimum amount of POFA in POBS LWAC would improve the workability and compressive strength of the concrete. However, inclusion of POFA more than optimum amount is not recommended as it will increase the water demand leading to lower workability and strength reduction.

  2. Numerical simulation of the time-dependent deformation behaviour of clay-stone rock mass at the Tournemire site with 2D and 3D models

    International Nuclear Information System (INIS)

    Rutenberg, M.; Lux, K.H.

    2010-01-01

    Document available in extended abstract form only. Modern repository research foregrounds physico-chemical processes (mechanical, hydraulic, thermal, chemical) and their interactions taking place in the near field and the far field of the geological system being explored. With regard to load bearing behaviour and preservation of barrier integrity, and with the general objective of complete confinement of the waste in the isolating rock zone, the focus is especially on geomechanical processes induced by excavation - including the influences on and by hydraulic, thermal, and chemical processes - as well as on thermal processes induced by heat generation of the deposited radioactive waste and their effects on mechanical and hydraulic processes. In order to improve assessments of the mechanical stability and, in case of a water saturated rock formation, of the hydraulic effects on the host rock of the repository, suitable physical models for numerical simulations of rock and rock mass behaviour have to be found and to be validated. Because of their radionuclide retention capacity, their low water permeability, and their resistance to water, clay-stone rock masses form a reasonable alternative to e.g. salt rock masses as a host rock for deep geological repositories. In past decades, various working groups at an international level have elaborated a broad experimental and theoretical understanding of the geomechanical and geo-hydraulic behaviour of clay-stones and applied this know-how to geologic repository components, e.g. in the context of engineering studies, or in the back-analysis of field tests. In this context, measurement results revealed a continuing convergence of drift walls lasting for a few years after completion of excavation. Possible reasons for this time-dependent deformation behaviour of the clay-stone rock mass might be: - viscous properties of the material from a phenomenological point of view, meaning a constant stress state leading to increasing

  3. STRESSES AND DEFORMABILITY OF ROCK MASS UPON OPEN PIT EXPLOITATION OF DIMENSION STONE

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    Siniša Dunda

    2003-12-01

    Full Text Available The appearance of increased stresses and deformability of rock mass in the quarry of Zečevo (exploitation field of Selca – island of Brač has caused a considerable decrease of usability of mineral raw materials, which put into question the survival of the pit. Therefore the research and measurements of the state of stresses and deformability of rock mass within the pit were carried out. Besides detailed laboratory testings (testings on small samples performed were trial in-situ testings on large samples including the corresponding numerical analyses. The exploitation of dimension stone by sowing regularly shaped rectangular blocks has been proved to be appropriate for in-situ testing of bending strength. The paper presents the results of carried out laboratory testings, in-situ testings of bending strength including measuring of deformations after sowing cuts and numerical analyses by which the possible range of horizontal stresses was determined. Since for the case of massive rocks, for which the continuum concept is applied, there are no specifically defined methods of corrections, presented is a possible relation for correction of input size values based on the carried out laboratory and in-situ testings.

  4. Three-dimensional shape analysis of coarse aggregates: New techniques for and preliminary results on several different coarse aggregates and reference rocks

    International Nuclear Information System (INIS)

    Erdogan, S.T.; Quiroga, P.N.; Fowler, D.W.; Saleh, H.A.; Livingston, R.A.; Garboczi, E.J.; Ketcham, P.M.; Hagedorn, J.G.; Satterfield, S.G.

    2006-01-01

    The shape of aggregates used in concrete is an important parameter that helps determine many concrete properties, especially the rheology of fresh concrete and early-age mechanical properties. This paper discusses the sample preparation and image analysis techniques necessary for obtaining an aggregate particle image in 3-D, using X-ray computed tomography, which is then suitable for spherical harmonic analysis. The shapes of three reference rocks are analyzed for uncertainty determination via direct comparison to the geometry of their reconstructed images. A Virtual Reality Modeling Language technique is demonstrated that can give quick and accurate 3-D views of aggregates. Shape data on several different kinds of coarse aggregates are compared and used to illustrate potential mathematical shape analyses made possible by the spherical harmonic information

  5. Assessment of aggregate quality and petrographic properties' influence on rock quality: A case study from Nordland county, Norway

    Science.gov (United States)

    Kløve Keiding, Jakob; Erichsen, Eyolf; Heldal, Tom; Aslaksen Aasly, Kari

    2017-04-01

    Good access to construction materials is crucial for future infrastructure development and continued economic growth. In Norway >80 % of construction materials come from crushed aggregates and represent an growing share of the consumption. Although recycling to some extend can cover the need for construction materials, economic growth, increasing population and urbanization necessitates exploitation of new rock resources in Norway as well as many other parts of the world. Aggregates must fulfill a number of technical requirements to ensure high quality and long life expectancy of new roads, buildings and structures. Aggregates also have to be extracted near the consumer market. Particularly for road construction strict criteria are in place for wearing course for roads with high traffic density. Thus knowledge of mechanical rock quality is paramount for both exploitation as well as future resource and land-use planning but is often not assessed or mapped beyond the quarry scale. The Geological survey of Norway runs a database with information about crushed aggregate deposits from >1500 Norwegian quarries and sample sites. Here we use mechanical test analyses from the database to assess the aggregate quality in the Nordland county, Norway. Maps have been produced linking bed rock geology with rock quality parameters. The survey documents that the county is challenged in meeting the requirements for roads with high traffic density and especially in the middle parts of the county many samples have weak mechanical properties. This to some degree reflect that weak Cambro-Silurian rocks like phyllite, schist, carbonate and greenstone are abundant in Nordland. Typically mechanically stronger rock types such as gabbro, monzonite and granite are also exposed in large parts of the county, but are also characterized by relative poor or very variable mechanical test quality. Preliminary results indicate that many intrinsic parameters influence the mechanical rock strength, but

  6. Study of the fracture behavior of mortar and concretes with crushed rock or pebble aggregates

    Directory of Open Access Journals (Sweden)

    Sebastião Ribeiro

    2011-03-01

    Full Text Available The objective of this work was to compare the fracture energy of mortar and concretes produced with crushed rock and pebble aggregates using zero, 10, 20, 30 and 40% of aggregates mixed with standard mortar and applying the wedge splitting method to achieve stable crack propagation. The samples were cast in a special mold and cured for 28 days, after which they were subjected to crack propagation tests by the wedge splitting method to determine the fracture energies of the mortar and concrete. The concretes showed higher fracture energy than the mortar, and the concretes containing crushed rock showed higher resistance to crack propagation than all the compositions containing pebbles. The fracture energy varied from 38 to 55 J.m-2. A comparison of the number of aggregates that separated from the two concrete matrices with the highest fracture energies indicated that the concrete containing pebbles crumbled more easily and was therefore less resistant to crack propagation.

  7. Rock Pore Structure as Main Reason of Rock Deterioration

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    Ondrášik Martin

    2014-03-01

    Full Text Available Crashed or dimensional rocks have been used as natural construction material, decoration stone or as material for artistic sculptures. Especially old historical towns not only in Slovakia have had experiences with use of stones for construction purposes for centuries. The whole buildings were made from dimensional stone, like sandstone, limestone or rhyolite. Pavements were made especially from basalt, andesite, rhyolite or granite. Also the most common modern construction material - concrete includes large amounts of crashed rock, especially limestone, dolostone and andesite.

  8. Uranium distribution and radon exhalation from Brazilian dimension stones

    International Nuclear Information System (INIS)

    Amaral, P.G.Q.; Galembeck, T.M.B.; Bonotto, D.M.; Artur, A.C.

    2012-01-01

    This paper provides evaluations of the radiometric behavior and exhalation patterns of radon gas in decorative and dimension stones explored in the Brazilian states of Minas Gerais and Espírito Santo, given the importance of determining radon gas concentrations in human-inhabited environments. A total of 10 silicate rock types were studied, featuring different petrographic/petrophysical characteristics given by seven magmatic rocks (three of which are granitic pegmatites) and three metamorphic rocks. The study, comprising radiometric data of U and monitoring of 222 Rn gas exhalation, shows a strong correlation between petrographic parameters and the physical properties of rocks. U levels ranged between 2.9 and 37 ppm, revealing a good coherence between the presence and the absence of radioactive element-bearing accessory minerals for each rock type. The rate of radon exhalation from the stones is related to the petrographic/petrophysical features of each material. By comparing the 222 Rn level generated by a rock to the amount effectively emanated by it, the rate of emanated gas proves to be insignificant; also, a rock that produces more Rn will not always emanate more. Simulations performed to estimate the radon levels inside residences or any given indoor environment showed that nine samples attained values below the 4 pCi/L EPA limit, whereas one was above that limit. - Highlights: ► Integration of distinct radiometric data acquired in dimension stones. ► Dimension stones are extensively commercialized abroad. ► Rn exhalation above the EPA threshold limit of 4 pCi/L.

  9. Uranium distribution and radon exhalation from Brazilian dimension stones

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, P.G.Q.; Galembeck, T.M.B. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Bonotto, D.M., E-mail: danielbonotto@yahoo.com.br [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Artur, A.C. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil)

    2012-04-15

    This paper provides evaluations of the radiometric behavior and exhalation patterns of radon gas in decorative and dimension stones explored in the Brazilian states of Minas Gerais and Espirito Santo, given the importance of determining radon gas concentrations in human-inhabited environments. A total of 10 silicate rock types were studied, featuring different petrographic/petrophysical characteristics given by seven magmatic rocks (three of which are granitic pegmatites) and three metamorphic rocks. The study, comprising radiometric data of U and monitoring of {sup 222}Rn gas exhalation, shows a strong correlation between petrographic parameters and the physical properties of rocks. U levels ranged between 2.9 and 37 ppm, revealing a good coherence between the presence and the absence of radioactive element-bearing accessory minerals for each rock type. The rate of radon exhalation from the stones is related to the petrographic/petrophysical features of each material. By comparing the {sup 222}Rn level generated by a rock to the amount effectively emanated by it, the rate of emanated gas proves to be insignificant; also, a rock that produces more Rn will not always emanate more. Simulations performed to estimate the radon levels inside residences or any given indoor environment showed that nine samples attained values below the 4 pCi/L EPA limit, whereas one was above that limit. - Highlights: Black-Right-Pointing-Pointer Integration of distinct radiometric data acquired in dimension stones. Black-Right-Pointing-Pointer Dimension stones are extensively commercialized abroad. Black-Right-Pointing-Pointer Rn exhalation above the EPA threshold limit of 4 pCi/L.

  10. "Stone Walks": Inhuman Animacies and Queer Archives of Feeling

    Science.gov (United States)

    Springgay, Stephanie; Truman, Sarah E.

    2017-01-01

    Excavating what Jeffrey Cohen [2015. "Stone: An ecology of the inhuman." Minneapolis: University of Minnesota Press] calls "lithic ecomateriality," in this paper we illustrate how rocks have traditionally been conceptualized through three tropes: rocks as insensate; rocks as personified; and rocks as transformative. We take up…

  11. Novelda Stone: widely used within the Spanish architectural heritage

    OpenAIRE

    Fort, R.; Bernabeu, A.; García del Cura, M. A.; López de Azcona, M. C.; Ordóñez, S.; Mingarro, F.

    2002-01-01

    Novelda Stone is a calcareous rock, of the biocalcarenite type. It is extracted from the «Vinalopó Medio» area (Alicante, eastern Spain). Novelda stone is known as construction material from the 13th century. From final of the 19th century until the present time, it has been used in Madrid, Valencia and Alicante. In the past, the main quarries from which this type of rock was extracted were located in the municipal districts of Monóvar (Almorquí Stone), Sax (Portazgo Stone) and Elda (Bateig S...

  12. "Sydney sandstone": Heritage Stone from Australia

    Science.gov (United States)

    Cooper, Barry; Kramar, Sabina

    2014-05-01

    Sydney is Australia's oldest city being founded in 1788. The city was fortunate to be established on an extensive and a relatively undeformed layer of lithified quartz sandstone of Triassic age that has proved to be an ideal building stone. The stone has been long identified by geologists as the Hawkesbury Sandstone. On the other hand the term "Sydney sandstone" has also been widely used over a long period, even to the extent of being utilised as the title of published books, so its formal designation as a heritage stone will immediately formalise this term. The oldest international usage is believed to be its use in the construction of the Stone Store at Kerikeri, New Zealand (1832-1836). In the late 19th century, public buildings such as hospitals, court houses as well as the prominent Sydney Town Hall, Sydney General Post Office, Art Gallery of New South Wales, State Library of New South Wales as well as numerous schools, churches, office building buildings, University, hotels, houses, retaining walls were all constructed using Sydney sandstone. Innumerable sculptures utilising the gold-coloured stone also embellished the city ranging from decorative friezes and capitals on building to significant monuments. Also in the late 19th and early 20th century, Sydney sandstone was used for major construction in most other major Australian cities especially Melbourne, Adelaide and Brisbane to the extent that complaints were expressed that suitable local stone materials were being neglected. Quarrying of Sydney sandstone continues today. In 2000 it was recorded noted that there were 33 significant operating Sydney sandstone quarries including aggregate and dimension stone operations. In addition sandstone continues to be sourced today from construction sites across the city area. Today major dimension stone producers (eg Gosford Quarries) sell Sydney sandstone not only into the Sydney market but also on national and international markets as cladding and paving products

  13. Crushed aggregates for roads and their properties for frost protection

    Science.gov (United States)

    Kuznetsova, Elena; Willy Danielsen, Svein

    2015-04-01

    Crushed aggregates for roads and their properties for frost protection Elena Kuznetsova, NTNU and Svein Willy Danielsen, SINTEF With natural (fluvial, glaciofluvial) sand/gravel resources being rapidly depleted in many countries, the last decade has seen a significant trend towards using more alternative materials for construction purpose. In Norway the development and implementation of crushed aggregate technology has been the most important way to get around the problem with increased resource scarcity. Today Norway is one the European countries with the highest percentage of crushed/manufactured aggregates. A crushed product will reveal a different particle size distribution, a sharper, more angular particle shape, and not least - a significantly different mineral composition. The latter may often be characterised by more polymineral composition, and it will also much more depend on the local bedrock. When handled with care and knowledge, these differences can give the user a lot of new opportunities relating to materials design. Norwegian road construction practice has changed significantly during the last 40 years due to the replacement of gravel by crushed rock materials in the granular layers of the pavements. The use of non-processed rock materials from blasting was allowed in the subbase layer until 2012. This was a reason for a lot of problems with frost heaving due to inhomogeneity of this material, and in practice it was difficult to control the size of large stones. Since 2012 there is a requirement that rock materials for use in the subbase layer shall be crushed (Handbook N200, 2014). During the spring 2014 The Norwegian Public Roads Administration introduced a new handbook with requirements for roads construction in Norway, including new specifications for the frost protection layer. When pavements are constructed over moist and/or frost susceptible soils in cold and humid environments, the frost protection layer also becomes a very important part

  14. Crushed Stone Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes crushed stone operations in the United States. These data were obtained from information reported voluntarily to the USGS by the aggregate...

  15. Ornamental Stones and Gemstones: The limits of heritage stone designation: The case for and against Australian Precious Opal

    Science.gov (United States)

    Cooper, Barry

    2015-04-01

    When the international designation of natural stone types was first mooted in 2007, stones that were utilised in building and construction were the primary focus of attention. However following public discussion it soon became apparent that sculptural stones, stone used for utilitarian purposes such as millstones, as well as archaeological materials including stones used by early man could all be positively assessed as a potential Global Heritage Stone Resource (GHSR). Over the past 2 years it has been realised there is also a range of ornamental and semi-precious stones that may also be considered in the same international context. Examples in this respect include Imperial Porphyry sourced from Egypt that was much prized in the ancient world and "Derbyshire Blue John" a variety of fluorspar from central England that was used for vases, chalices, urns, candle sticks, jars, bowls door, jewellery and fire-place surrounds, especially in the 18th and 19th centuries. It is at this point that rock materials, sometimes used as gemstones, impinge on the domain of typical heritage stones. In Australia, the gemstone most identifiable with the country is precious opal formed by sedimentary processes in the Great Artesian Basin. In this paper the question is asked whether "Australian Precious Opal" could be or should be considered as a heritage stone of international significance. Immediately Australian Precious Opal satisfies several GHSR criteria including historic use for more than 50 years and wide-ranging utilisation for prestige jewellery around the world. It is also recognised as a cultural icon including association with national identity in Australia as it is legally defined as Australia's "National Gemstone" as well as being the "Gemstone Emblem" for the State of South Australia. Opal continues to be mined. Designation of Australian Precious Opal as a Global Heritage Stone Resource would likely involve formal international recognition of Australian opal in the

  16. Numerical simulation of the time-dependent deformation behaviour of clay-stone rock mass at the Tournemire site with 2D and 3D models

    International Nuclear Information System (INIS)

    Rutenberg, M.; Lux, K. H.

    2011-01-01

    Clay-stone rock masses are a reasonable alternative to e.g. salt rock masses as a host rock for underground radioactive waste repositories because of their very low permeability as well as their radionuclide retention capacity. Though clay-stone has been explored for many years, there is still a need for further research on its hydro-mechanical behaviour. Convergence measurements over a 4-year period in the tunnel system of the argillaceous Tournemire site in France yielded the presence of a time-dependent deformation behaviour in indurated clay. Moreover, a mine-by test was carried out with extensometer measurements capturing the rock mass deformation during the excavation process of a new gallery in 2003.This work focuses on the validation of a constitutive model by means of a three-dimensional (3D) simulation of the mine-by test. The utilised constitutive model Hou/Lux-T is based on the viscous constitutive model Lubby2 with which time-dependent deformation behaviour of salt rock can appropriately be simulated. It has been adapted to clay-stone by considering anisotropy effects, and in addition it features a strain-dependent fracture and failure criterion. The results of the mine-by-test simulation show that the calculated stresses and deformations in the rock mass seem to behave reasonably under this constitutive model with respect to time-dependency. A comparison of the 3D results to the results of a simplified two-dimensional (2D) simulation confirms the adequacy of using a 2D model with the constitutive model Hou/Lux-T for the setting at hand, described in the text (material parameters, time scale), in order to assess load-bearing capacity and deformability of the gallery near field away from heading face and tunnel crossing. Finally, a comparison of the 3D simulation results to the extensometer measurement results yields the principal ability of the used constitutive model to describe time-dependent evolutions of stresses and deformations during a three

  17. Rock and stone weathering at Citadel fortifications, Gozo (Malta): benefits from terrestrial laser scanning combined with conventional investigations

    Science.gov (United States)

    Tapete, D.; Gigli, G.; Mugnai, F.; Vannocci, P.; Pecchioni, E.; Morelli, S.; Fanti, R.; Casagli, N.

    2012-04-01

    Military architecture heritage is frequently built on rock masses affected by slope instability and weathering processes, which progressively undermine the foundations and cause collapses and toppling of the masonries. The latter can be also weakened by alteration of the stone surfaces, as a consequence of the interactions with the local environmental conditions. These conservation issues are emphasized for those sites, whose susceptibility to structural damages is also due to the similarity between the lithotypes constituting the geologic substratum and the construction materials. Effective solutions for the protection from such a type of phenomena can be achieved if the whole "rock mass - built heritage system" is analyzed. In this perspective, we propose a new approach for the study of the weathering processes affecting historic hilltop sites, taking benefits from the combination of terrestrial laser scanning (TLS) and conventional investigations, the latter including geotechnical and minero-petrographic analyses. In particular, the results here presented were obtained from specific tests on the fortifications of Citadel, Gozo (Malta), performed in co-operation with the Restoration Unit, Works Division, Maltese Ministry for Resources and Rural Affairs and the private company Politecnica Ingegneria e Architettura. The Citadel fortifications are built at the top of a relatively stiff and brittle limestone plate, formed by Upper Coralline Limestone (UCL) and overlying a thick Blue Clay (BC) layer. Differential weathering creates extensively fractured ledges on the cap and erosion niches in the strata beneath, thereby favouring block detachment, even rockfall events, such as the last one occurred in 2001. The locally quarried Globigerina Limestone (GL), historically employed in restoration masonries, is also exposed to alveolization and powdering, and several collapses damaged the underwalling interventions. Since the erosion pattern distribution suggested a

  18. Sustainable materials used as stone column filler: A short review

    Science.gov (United States)

    Zukri, Azhani; Nazir, Ramli

    2018-04-01

    Stone columns (also known as granular piles) are one of the methods for soft soil stabilization and typically used to increase bearing capacity and stability of slope.; Apart from decreasing the compressibility of loose and fine graded soils, it also accelerates the consolidation effect by improving the drainage path for pore water pressure dissipation and reduces the liquefaction potential of soils during earthquake event. Stone columns are probably the most “natural” ground treatment method or foundation system in existence to date. The benefit of stone columns is owing to the partial replacement of compressible soil by more competent materials such as stone aggregate, sand and other granular materials. These substitutes also act as reinforcement material, hence increasing overall strength and stiffness of the soft soil. Nowadays, a number of research has been conducted on the behaviour and performance of stone columns with various materials utilized as column filler replacing the normal aggregate. This paper will review extensively on previously conducted research on some of the materials used as stone column backfill materials, its suitability and the effectiveness as a substitute for regular aggregates in soft soil improvement works.

  19. Investigations of excavated clay-stone as backfill/seal material

    International Nuclear Information System (INIS)

    Zhang, Chun-Liang

    2012-01-01

    Document available in extended abstract form only. Crushed clay-stone produced by excavation activities of repository drifts has been investigated as backfill/seal material at the GRS laboratory. The raw aggregate with coarse grains is considered to be used for backfilling the repository openings and, in mixture with bentonite, for sealing the boreholes, drifts and shafts. The GRS research programme focused on characterizing the thermo-hydro-mechanical properties of the excavated Callovo-Oxfordian clay-stone (COX) and the clay-stone-bentonite mixtures, including mechanical compaction, gas and water permeability as function of porosity, water retention and saturation, swelling capacity, and thermal properties of the materials. The most important results are presented in this paper. Figure 1 shows the compaction and permeability behaviour of the excavated clay-stone with grains up to a size of 32 mm. The results were obtained on large samples of 280 mm diameter and 680 mm height under quasi-hydrostatic compression. The porosity and permeability decrease with increasing load. The porosity-mean stress relation is non-linear and may be expressed by an exponential function. The backfill becomes stiffer at low porosities and can sustain certain deviatoric loads. At porosity of ∼21 %, the strength is characterized by an inherent cohesion of 3.7 MPa and an internal friction angle of 12 deg.. Additionally, the compaction is also dependent on time or loading rate, water content, and temperature. The compaction of the porous backfill material leads to a reduction in permeability. The measured gas permeability decreases much faster at low porosities below ∼25 %. The gas permeability at porosity of ∼20 % becomes as low as that of 10 -20 - 10 -21 m 2 for the intact clay rock. This is probably due to disconnection of the pore network during the compaction. As sealing material, powdered COX clay-stone was mixed with MX80 bentonite powder in different ratios and compacted to

  20. Leaching properties of natural aggregates. Rock materials and tills; Lakegenskaper foer naturballast. Bergmaterial och moraener

    Energy Technology Data Exchange (ETDEWEB)

    Ekvall, Annika; Bahr, Bo von; Andersson, Tove; Lax, Kaj; Aakesson, Urban [Swedish National Testing and Research Inst., Boraas (Sweden)

    2006-02-15

    The aim of this project is to produce leaching data for natural aggregates needed for assessment of the environmental impact of alternative materials aimed for use in for example road constructions. Both rock materials and tills are tested. The results shows that very little is leached from natural aggregate. A comparison with landfill criteria for inert waste and the Swedish regulations for drinking water shows that a few samples exceeds the criteria for fluoride ions. All other values are lower then these criteria, and a vast majority of the measurements are below the quantification limit.

  1. Dawsonite and other carbonate veins in the Cretaceous Izumi Group, SW Japan: a natural support for fracture self-sealing in mud-stone cap-rock in CGS?

    Energy Technology Data Exchange (ETDEWEB)

    Okuyama, Yasuko; Funatsu, Takahiro; Fujii, Takashi [Institute for Geo-Resources and environment, GSJ, AISI, 1-1-1 Higashi, Central 7, Tsukuba, ibaraki 305-8567 (Japan); Take, Shuji [Kishiwada Nature Club, c/o Kishiwada City Natural History Museum, Sakai-Machi 5-6, Kishiwada, Osaka 596-0072 (Japan)

    2013-07-01

    Dawsonite-bearing carbonate veins are abundant in a compact mud-stone layer of the lower part of the Izumi Group, SW Japan. The mode of occurrence of the veins probably indicates fracturing and mineral sealing associated with upwelling of CO{sub 2}-rich fluid evolved in the reservoir beneath. The carbonate veins studied here can be a natural support to fracturing and healing of mud-stone cap-rock in the CO{sub 2} geological storage. (authors)

  2. Soap-stone in architecture of North European cities. A nomination as a candidate for a Global Heritage Stones Resource

    Science.gov (United States)

    Bulakh, Andrey

    2016-04-01

    Soap stone represents soft Proterozoic rock type from the deposit Nunnalahti situated on the western shore of the big Lake Pielinen in Eastern Finland. It consists of talc (40 - 50 %), magnesite MgCO3 (40 - 50 %), chlorite (5 - 8 %), dolomite, calcite, etc. The colour of the stone is very spectacular and varies from yellow and brownish-yellow to grey, greenish grey. The soft stone is a highly workable material for a sculptor's chisel. It was one of the most popular ornamental rocks used architecture of the Modern style in St Petersburg, Helsinki, Turku, Tampere and other North European cities lately in the XIX-th centuries. Examples are given and discussed. References: Bulakh, A.G., Abakumova, N.B., and Romanovsky, J.V. St Petersburg: a History in Stone. 2010. Print House of St Petersburg State University. 173 p. (In English).

  3. Behavior of crushed rock aggregates used in road construction exposed to cold climate conditions

    Science.gov (United States)

    Kuznetsova, Elena; Pérez Fortes, Ana Patricia; Anastasio, Sara; Willy Danielsen, Svein

    2016-04-01

    Presently, about 90% of the aggregate production in Europe comes from naturally occurring resources: quarries and pits. Due to the increased demand for sand and gravel for construction purposes, not only in building but also in road construction, the last decade has seen a significant trend towards the use of more crushed rock aggregates. This resource has been more and more preferred to sand and gravel thanks to the significant technological development of its process and use phase. The performance of the aggregates is generally evaluated depending on three main factors: the geological origin (mineral composition, texture, structure, degree of weathering), the aggregate processing (crushing, sieving, washing, storing) and the user technology for a specific area of use (e.g. road construction, asphalt binders). Nevertheless climatic conditions should carefully be taken into account in application such as road construction. Large temperature gradients and high levels of humidity are known to significantly affect the performance of the material. Although the problem is, at least in the asphalt field, considered mostly from the binder point of view, this article aims to investigate the effect of aggregate properties on road performance in cold climatic conditions. Two different climatic areas will be taken into account: Norway and Spain. While both these countries are listed among the main European producers of aggregates, they represent significantly different climatic regions. While Norwegian weather is characterized by humid cold winters and relatively mild summers, Spain has temperate climate with cold regions in mountainous and internal areas. Both countries have been significantly affected by climate change with increasing temperature variations and instability. At the same time, similar winter maintenance measures, including the use of a considerable amount of solid and liquid chemicals to avoid ice formation (e.g. NaCl) and/or to provide better friction, are

  4. Crushed rock sand – An economical and ecological alternative to natural sand to optimize concrete mix

    Directory of Open Access Journals (Sweden)

    Sanjay Mundra

    2016-09-01

    Full Text Available The study investigates the use of crushed rock sand as viable alternative to Natural River sand that is being conventionally used as fine aggregate in cement concrete. Various mix designs were developed for different grades of concrete based on IS, ACI and British codes using Natural River sand and crushed rock sand. In each case, the cube compressive strength test, and beam flexure tests were conducted. The results of the study show that, the strength properties of concrete using crushed rock sand are nearly similar to the conventional concrete. The study has shown that crushed stone sand can be used as economic and readily available alternative to river sand and can therefore help to arrest the detrimental effects on the environment caused due to excessive mining of river sand.

  5. Building stones can be of geoheritage significance

    Science.gov (United States)

    Brocx, Margaret; Semeniuk, Vic

    2017-04-01

    Building stones have generally been assigned values according to their cultural, aesthetic, and rarity significance, amongst other criteria, but they also may have geoheritage significance. This is akin to the geoheritage significance ascribed to minerals and fossils housed as ex situ specimens in museums. We proffer the notion that building stones can be of geoheritage value particularly where they comprise permanent buildings, they illustrate significant windows into the history of the Earth, and they can be visited as an ex situ museum locality (e.g., the "Blue Granite" of Iceland) for education as part of building-stone tours. For some rocks the quarries that supplied the building stone are no longer in existence and hence the building stones provide the only record of that type of material; for other rocks, the building stone may illustrate features in the lithology no longer present in the quarry itself (e.g., rare and large xenoliths). Building stones are particularly significant as they are often polished and manifest structures, fabrics, and textures not evident in outcrop. We illustrate here examples of building stone of geoheritage significance using Australian and International examples. Australian designated stones could include the "Sydney Sandstone" or "Victorian Bluestone". For international examples, there is the famous "Carrara Marble" in Italy and the widely known "Portland Limestone" from southern England, the latter having been utilized for St Pauls Cathedral in London and the UN building in New York City.

  6. Art Rocks with Rock Art!

    Science.gov (United States)

    Bickett, Marianne

    2011-01-01

    This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

  7. Durability and Testing of Stone for use in Rubblemound structures

    DEFF Research Database (Denmark)

    Magoon, O.T.; Baird, W.F.; Ahrends, J.P.

    1993-01-01

    Rubblemound structures protected from wave action by a layer of quarried rock (stones) are the most common form of breakwaters. While extensive guidelines and procedures exist to select the size of stone there is very little information available on procedures to be followed to assure the quality...

  8. Villamayor stone (Golden Stone) as a Global Heritage Stone Resource from Salamanca (NW of Spain)

    Science.gov (United States)

    Garcia-Talegon, Jacinta; Iñigo, Adolfo; Vicente-Tavera, Santiago

    2013-04-01

    Villamayor stone is an arkosic stone of Middle Eocene age and belongs to the Cabrerizos Sandstone Formation that comprising braided fluvial systems and paleosoils at the top of each stratigraphic sequence. The sandstone is known by several names: i) the Villamayor Stone because the quarries are located in Villamayor de Armuña village that are situated at 7 km to the North from Salamanca city; ii) the Golden Stone due to its patina that produced a ochreous/golden color on the façades of monuments of Salamanca (World Heritage City,1988) built in this Natural stone (one of the silicated rocks utilised). We present in this work, the Villamayor Stone to be candidate as Global Heritage Stone Resource. The Villamayor Stone were quarrying for the construction and ornamentation of Romanesque religious monuments as the Old Cathedral and San Julian church; Gothic (Spanish plateresc style) as the New Cathedral, San Esteban church and the sculpted façade of the Salamanca University, one of the oldest University in Europe (it had established in 1250); and this stone was one of the type of one of the most sumptuous Baroque monuments is the Main Square of the its galleries and arcades (1729). Also, this stone was used in building palaces, walls and reconstruction of Roman bridge. Currently, Villamayor Stone is being quarried by small and family companies, without a modernized processing, for cladding of the façades of the new buildings until that the construction sector was burst (in 2008 the international economic crisis). However, Villamayor Stone is the main stone material used in the city of Salamanca for the restoration of monuments and, even in small quantities when compared with just before the economic crisis, it would be of great importance for future generations protect their quarries and the craft of masonry. Villamayor Stone has several varieties from channels facies to floodplains facies, in this work the selected varieties are: i) the fine-grained stone

  9. Relationship between the incidence infection stones and the magnesium-calcium ratio of tap water.

    Science.gov (United States)

    Kohri, K; Ishikawa, Y; Iguchi, M; Kurita, T; Okada, Y; Yoshida, O

    1993-01-01

    In a previous study we showed that the magnesium-calcium ratio of tap water is negatively correlated with the incidence of calcium-containing urinary stones. In this study we examined the relationship between the incidence of struvite stones, water hardness and the regional geological features on the basis of our previous study and an epidemiological study of urolithiasis performed in Japan. The magnesium-calcium ratio of tap water was found to correlate positively with the incidence of struvite stones. The tap water magnesium-calcium ratio was high in regions of basalt and sedimentary rock and was low in granite and limestone areas. The incidence of struvite stones in the regions of basalt and sedimentary rock was higher than that in the granite and limestone areas. Thus, this study suggested that the incidence of struvite stones is related to the magnesium-calcium ratio of tap water and to the regional geology, as is the case for calcium-containing stones.

  10. Detection of endolithic spatial distribution in marble stone.

    Science.gov (United States)

    Casanova Municchia, A; Percario, Z; Caneva, G

    2014-10-01

    The penetration of endolithic microorganisms, which develop to depths of several millimetres or even centimetres into the stone, and the diffusion of their extracellular substances speeds up the stone deterioration process. The aim of this study was to investigate, using a confocal laser scanning microscopy with a double-staining, a marble rock sample by observing the endolithic spatial distribution and quantifying the volume they occupied within the stone, in order to understand the real impact of these microorganisms on the conservation of stone monuments. Often the only factors taken into account by biodeterioration studies regarding endolithic microorganisms, are spread and depth of penetration. Despite the knowledge of three-dimensional spatial distribution and quantification of volume, it is indispensable to understand the real damage caused by endolithic microorganisms to stone monuments. In this work, we analyze a marble rock sample using a confocal laser scanning microscopy stained with propidium iodide and Concavalin-A conjugate with the fluorophore Alexa Fluor 488, comparing these results with other techniques (SEM microscope, microphotographs of polished cross-sections and thin-section, PAS staining methods), An image analysis approach has also been applied. The use of confocal laser scanning microscopy with double staining shows clear evidence of the presence of endolithic microorganisms (cyanobacteria and fungi) as well as the extracellular polymeric substance matrix in a three-dimensional architecture as part of the rock sample, this technique, therefore, seems very useful when applied to restoration interventions on stone monuments when endolithic growth is suspected. © 2014 The Authors Journal of Microscopy © 2014 Royal Microscopical Society.

  11. Weathering and weathering rates of natural stone

    Science.gov (United States)

    Winkler, Erhard M.

    1987-06-01

    Physical and chemical weathering were studied as separate processes in the past. Recent research, however, shows that most processes are physicochemical in nature. The rates at which calcite and silica weather by dissolution are dependent on the regional and local climatic environment. The weathering of silicate rocks leaves discolored margins and rinds, a function of the rocks' permeability and of the climatic parameters. Salt action, the greatest disruptive factor, is complex and not yet fully understood in all its phases, but some of the causes of disruption are crystallization pressure, hydration pressure, and hygroscopic attraction of excess moisture. The decay of marble is complex, an interaction between disolution, crack-corrosion, and expansion-contraction cycies triggered by the release of residual stresses. Thin spalls of granites commonly found near the street level of buildings are generally caused by a combination of stress relief and salt action. To study and determine weathering rates of a variety of commercial stones, the National Bureau of Standards erected a Stone Exposure Test Wall in 1948. Of the many types of stone represented, only a few fossiliferous limestones permit a valid measurement of surface reduction in a polluted urban environment.

  12. Piedra Pajarilla: A candidate for nomination as Global Heritage Stone Resource from Spain

    Science.gov (United States)

    Pereira, Dolores; Gimeno, Ana; del Barrio, Santiago

    2013-04-01

    Piedra Pajarilla is a tourmaline bearing leucogranite outcropping at Martinamor, near Salamanca, Spain. It is part of the Hercynian granitic chain in the Spanish Central System. The stone received the local name "Piedra Pajarilla", meaning "Little Bird Stone" due to the shape of the many tourmaline aggregates that are the main visual feature of the rock. This local name has been extrapolated to every granitic stone used in the area, even if they differ significantly in mineralogy, and as recently tested in physical and mechanical properties as well. Here we present the nomination of Piedra Pajarilla as a suitable "Global Heritage Stone Resource". This stone ideally fits the newly proposed designation as it has been used since Roman times in Salamanca (Spain) and since the Middle Ages in the construction of major historic buildings, including both the Old and New Cathedrals, and many additional churches, castles and walls in the Salamanca area. Salamancás historic city core has been granted UNESCO World Heritage status in 1988, and all associated buildings, monuments and pedestrian streets are constructed from original materials. One of utilised materials, Piedra Pajarilla, was quarried for centuries from the immediate area. It was also the preferred building stone of many internationally renowned architects of Spanish origin during the 18th and 19th centuries especially involved in reconstruction following the Lisbon earthquake. Although the associated quarries are no longer active, the Piedra Pajarilla quarry sites remain relatively undisturbed and accessible. A renewal of quarrying is consequently feasible if additional stone supplies are required for heritage restoration. Thus there is also a need to preserve these historic quarries in anticipation of such work. The importance of Salamanca as emblematic heritage makes the historic stone quarries worthwhile to preserve as well. At the same time, Piedra Pajarilla can be considered as the first of several natural

  13. A comparative study of pulmonary Koch's among marble stone worker community of Bhedaghat and nonmarble stone worker community of Garha

    OpenAIRE

    Shashi Prabha Tomar; Avadhesh PS Kushwah; Sonjjoay Pande; Pushpraj S Baghel

    2014-01-01

    Introduction: Occupational stone dust exposure may result in several health risks tuberculosis (TB) silicosis, obstructive as well as restrictive lung diseases, among which TB is more prevalent in developing countries like India. Most people residing in Bhedaghat engaged in carving statues from variable stones and marble rocks belongs to poor socioeconomic conditions and unaware of the preventive measures. Ultimately they end up in chronic respiratory problems and various complications. Objec...

  14. Bulding and Ornamental Stone in the History of St Petersburg Architecture

    Science.gov (United States)

    Bulakh, Andrey

    2013-04-01

    First, the Our Lady of Kazan Orthodox Cathedral and some mansions are used to demonstrate Russian stones in the architectural décor of St Petersburg, XVIII-XX cc. These rocks are granites from Vyborg and Sortavala, lime tufa from Gatchina, marbles from Ruskeala and Juven at the Ladoga Lake, Tivdian marble, Shokshian quartzite, and black aspid slate of the Onega Lake. Later German and Polish sandstones and Finnish soap stone came to the city. Second, there is given a review of rock types used in St Petersburg at XX-XXI cc. margins. They are granites, granosyenites, syenites, gneisses, marbles, limestones both from Russia and from abroad. Which ones are more usual? From what regions did Russian stone come? References: 1) A.G.Bulakh, N.B.Abakumova, J.V.Romanovsky. St Petersburg: a History in Stone. 2010. Print. House of St Petersburg State University. 173 p. 2) A.Ya. Tutakova, A.Z. Romanovskiy, A.G. Bulakh, V.I. Leer. Dimension Stone of the Leningrad Region. Granites of the Karelia Isthmus in Architecture of the Modern St Petersburg. 2011. St Petersburg. 78 p. (In Russian).

  15. Introductory Overview of Stone Heritages in Japan

    Science.gov (United States)

    Kato, Hirokazu; Oikawa, Teruki; Fujita, Masayo; Yokoyama, Shunji

    2013-04-01

    As one contribution to 'Global Heritage Stone Resources' (GHSR), some stone heritages in Japan, which are nominated in the interim list, are briefly introduced. The geology of Japanese Islands where are the one of the most active areas in the history of the Earth, is very complicated. Therefore Japanese Islands consist of various kinds of minerals and rocks. Some of them were used to make stone implements and accessories. Japanese people also used to the best possible advantage to built tombstone, gate, pavement ,and the basement and wall of the large building such as temples, shrines, castles and modern buildings. 1. Stone Heritages of Pre-historical age: In the late Pleistocene and the early Holocene, ancient Japanese used obsidian cooled rapidly from rhyolitic magma.to make small implements and accessories. For example, Shirataki, Hokkaido (north island) is the largest place producing obsidian in Japan where Paleolithic people made arrowhead, knives and so on. Another example, Jade yielded in Itoigawa City, Japan Sea coast of central Japan, was made in the metamorphic rock about five hundred million years ago. Itoigawa area is only one place where jade is abundantly produced in Japan. Ancient people had been already collected and processed to ornaments although it is very hard and traded in wide area more than several thousand years ago. 2. Stone Heritages of Historical age: 2.1 Archaeological remains: In the Kofun (old mound) period (250 to 538 AD), stone burial chambers were used for old mounds to preserve against the putrefaction and to protect from the theft. For example, Ishibutai Kofun ("ishi" means "stone" and "butai" means "stage") in Nara old capital city, southwest Japan, is the largest known megalithic structure made of granite in Japan. 2.2 Stone walls of some typical castles Stones used is because of not only the rich reserves of rocks but also restriction of transportation. Osaka (second biggest city) castle, are composed of Cretaceous granite

  16. A Lion of a Stone

    Science.gov (United States)

    2004-01-01

    This approximate true-color image of the rock called 'Lion Stone' was acquired by the Mars Exploration Rover Opportunity's panoramic camera on sol 104 (May 9, 2004). The rock stands about 10 centimeters tall (about 4 inches) and is about 30 centimeters long (12 inches). Plans for the coming sols include investigating the rock with the spectrometers on the rover's instrument arm. This image was generated using the camera's L2 (750-nanometer), L5 (530-nanometer) and L6 (480-nanometer) filters.

  17. Lessons from a Stone Farm

    Science.gov (United States)

    Kavanagh, John P.; Rao, P. Nagaraj

    2007-04-01

    The stone farm is a system for measuring macroscopic stone growth of 12 calcium stones simultaneously. It is based on mixed suspension, mixed product removal continuous crystallization principles and the stones are grown continuously for about 500 hours or more. The growth of the stones follows a surface area dependent pattern and the growth rate constants are very similar irrespective of whether the stating materials are fragments of human stone or pieces of marble chip. Increasing citrate from 2mM to 6mM caused a significant growth inhibition which persisted in the presence of urinary macromolecules. Phytate was a very effective inhibitor (about 50% at sub-μM concentrations) but the effective concentration was increased by an order of magnitude in the presence of urinary macromolecules. The effective concentration for inhibition in a crystallization assay was a further two orders of magnitude higher. Urinary macromolecules or almost whole urine were also strongly inhibitory although neither human serum albumin nor bovine mucin had any great effect. The relationship between the size distribution of crystals in suspension and the stone enlargement rate suggests that the primary enlargement mechanism for these in vitro stones is through aggregation. The stone farm is a powerful tool with which to study crystallization inhibitors in a new light. Some differences between inhibition of crystallization and inhibition of stone growth have emerged and we have obtained quantitative evidence on the mechanism of stone enlargement in vitro. Our findings suggest that the interface between crystals in suspension and the stone surface is the key to controlling stone enlargement.

  18. A brief review of the construction aggregates market

    Science.gov (United States)

    Willett, Jason Christopher

    2012-01-01

    The U.S. Geological Survey defines the construction aggregates industry as those companies that mine and process crushed stone and/or construction sand and gravel. Aggregates have been used from the earliest times of our civilization for a variety of purposes - construction being the major use. As construction aggregates, crushed stone and construction sand and gravel are the basic raw materials used to build the foundation for modern society. The widespread use of construction aggregates is the result of their general availability throughout the country and around the world along with their relatively low cost. Although construction aggregates have a low unit value, their widespread use makes them major contributors to, and indicators of, the economic well-being of the nation.

  19. The material from Lampung as coarse aggregate to substitute andesite for concrete-making

    Science.gov (United States)

    Amin, M.; Supriyatna, Y. I.; Sumardi, S.

    2018-01-01

    Andesite stone is usually used for split stone material in the concrete making. However, its availability is decreasing. Lampung province has natural resources that can be used for coarse aggregate materials to substitute andesite stone. These natural materials include limestone, feldspar stone, basalt, granite, and slags from iron processing waste. Therefore, a research on optimizing natural materials in Lampung to substitute andesite stone for concrete making is required. This research used laboratory experiment method. The research activities included making cubical object samples of 150 x 150 x 150 mm with material composition referring to a standard of K.200 and w/c 0.61. Concrete making by using varying types of aggregates (basalt, limestone, slag) and aggregate sizes (A = 5-15 mm, B = 15-25 mm, and 25-50 mm) was followed by compressive strength test. The results showed that the obtained optimal compressive strengths for basalt were 24.47 MPa for 50-150 mm aggregate sizes, 21.2 MPa for 15-25 mm aggregate sizes, and 20.7 MPa for 25-50 mm aggregate sizes. These results of basalt compressive strength values were higher than the same result for andesite (19.69 MPa for 50-150 mm aggregate sizes), slag (22.72 MPa for 50-150 mm aggregate sizes), and limestone (19.69 Mpa for 50-150 mm aggregate sizes). These results indicated that basalt, limestone, and slag aggregates were good enough to substitute andesite as materials for concrete making. Therefore, natural resources in Lampung can be optimized as construction materials in concrete making.

  20. The present state and future of the development of dimension stone mining in Slovak conditions

    Directory of Open Access Journals (Sweden)

    Viliam Žiaran

    2005-03-01

    Full Text Available In comparing to both ores and energetical minerals there are occurences of extremly rich non-methallics minerals on the Slovak territory. These minerals represent very large-scale sortiment with a considerable amount of verified reserves. Reserves of magnesite, salt rock, dolomite, limestone, talc, bentonite, clays and another construction minerals present many possibilities of their industrial utilization. A specific case is the mining of dimension stones such as stable ingeneous,sedimentary and metamorphic rocks that are mined in the open-pit blocks. Applicable to the production of both ingeneous stone and gross stone [3].The open-pit mining and dimension stone processing by the both above mentioned stone productions forms are focused mainly to the external and internal building industry. Despite of the fact that the natural reserves of dimension stone are limited at the Slovak territory, being distributed at large numbers of open-pits mines, from the point of view of the next development of the dimension stone industry its technical and economic vitalitycan be expected. The paper deals with both the technological and ecological mining problems of dimension stone and shows the possibilities how to improve both the works productivity and quality of products including the ecological impacts by the dimension stone mining.

  1. Wave boundary layer over a stone-covered bed

    DEFF Research Database (Denmark)

    Dixen, Martin; Hatipoglu, Figen; Sumer, B. Mutlu

    2008-01-01

    This paper summarizes the results of an experimental investigation on wave boundary layers over a bed with large roughness, simulating stone/rock/armour block cover on the sea bottom. The roughness elements used in the experiments were stones the size of 1.4cm and 3.85cm in one group of experiments...

  2. [Components of urinary crystallites in urine of uric acid stone formers and its relationship with formation of stones].

    Science.gov (United States)

    Huang, Zhi-jie; Tan, Jin; Ouyang, Jian-ming

    2010-09-01

    The components, zeta potential, morphology of nanocrystallites in urines of 10 uric acid stone formers as well as their relationship with the formation of uric acid stones were comparatively studied using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, nanoparticle size analyzer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The urine pH of uric acid stone formers was relatively low within the range of 4.8 to 5.7. The main constituent of urinary crystallites was uric acid. Their particle size distribution was highly uneven, ranging from several nanometers to several tens of micrometers, and obvious aggregation was observed. The zeta potential of urinary crystallites in ten lithogenic patients was -6.02 mV, which was higher than that in ten normal subjects (-10.1 mV). After drug therapies (potassium citrate was taken), the urine pH value of the uric acid stone formers increased to 6.5 or so, and at this pH value most of the uric acid had changed to urate. Since the solubility of urate increased greatly than uric acid, the risk of the formation of uric acid stone reduced. The results in this paper showed that there was a close relationship among stone components, urinary crystallites composition and urine pH.

  3. The geological heritage of Piedmont Region: Turin a "Stone-Town"

    Science.gov (United States)

    Borghi, Alessandro; Castelli, Daniele; Costa, Emanuele; d'Atri, Anna; Antonella Dino, Giovanna; Favero, Sergio; Ferrando, Simona; Groppo, Chiara; Martire, Luca; Piervittori, Rosanna; Rolfo, Franco; Rossetti, Piergiorgio; Vaggelli, Gloria

    2013-04-01

    The stone resources have always been a major source of material in the building and, in particular, as raw material to create the masterpieces of sculpture and architecture that are now part of the cultural heritage of the humanity. Therefore, knowledge of stone resources, their mineral-petrographic features, their use and quarrying and working techniques from antiquity to the present, can provide a broad overview of the historical and cultural significance of these materials, stressing the importance of a relevant economic activity in the history and traditions of different cultures that have developed over the centuries in the Mediterranean area. In particular, in Piedmont, stone has always been the most widely used building material, characterizing the strong architectural identity of the city of Turin. Here the stone have been widely used in the historical and contemporary buildings, monuments and urban art. From Roman times to the '700, marbles were the rocks used in construction of more value. Starting from '800, granites and other silicate rocks were progressively used thanks to the development of technologies for their exploitation and processing. The study of stone resources is also of particular importance for the proper preservation of architectural and artistic heritage. Often, the task of restoration of works of art was carried out with stones aesthetically similar to the originals for color. Only recently, chances to find the same original material, identifying the place of origin, has become object of study and interest. The great variety of ornamental and building stones found in Turin is certainly due to the highly composite geological nature of our region. In Piedmont, in fact, there are geological features very different from each other as the western portion of the metamorphic Alpine chain, the sedimentary Tertiary Piedmont basin (Langhe and Monferrato) and a small sector of the Northern Apennine. Turin Urban Geosite represents the symbol place

  4. Evaluation of Skid Resistance of Wearing Course Made Of Stone Mastic Asphalt Mixture in Laboratory Conditions

    Science.gov (United States)

    Wasilewska, Marta

    2017-10-01

    This paper presents the comparison of skid resistance of wearing course made of SMA (Stone Mastic Asphalt) mixtures which differ in resistance to polishing of coarse aggregate. Dolomite, limestone, granite and trachybasalt were taken for investigation. SMA mixtures have the same nominal size of aggregate (11 mm) and very similar aggregate particle-size distribution in mineral mixtures. Tested SMA11 mixtures were designed according to EN 13108-5 and Polish National Specification WT-2: 2014. Evaluation of the skid resistance has been performed using the FAP (Friction After Polishing) test equipment also known as the Wehner/Schulze machine. Laboratory method enables to compare the skid resistance of different types of mixtures under specified conditions simulating polishing processes. Tests were performed on both the specimens made of each coarse aggregate and SMA11 mixtures containing these aggregates. Measuring of friction coefficient μm was conducted before and during polishing process up to 180 0000 passes of polishing head. Comparison of the results showed differences in sensitivity to polishing among particular mixtures which depend on the petrographic properties of rock used to produce aggregate. Limestone and dolomite tend to have a fairly uniform texture with low hardness which makes these rock types susceptible to rapid polishing. This caused lower coefficient of friction for SMA11 mixtures with limestone and dolomite in comparison with other test mixtures. These significant differences were already registered at the beginning of the polishing process. Limestone aggregate had lower value of μm before starting the process than trachybasalt and granite aggregate after its completion. Despite the differences in structure and mineralogical composition between the granite and trachybasalt, slightly different values of the friction coefficient at the end of polishing were obtained. Images of the surface were taken with the optical microscope for better

  5. Alteration dependent physical-mechanical properties of quartz-diorite building stones

    Directory of Open Access Journals (Sweden)

    Masoud Torkan

    2016-12-01

    Full Text Available The microscopic and geomechanical properties of igneous building stones include the level of alteration, presence of micro cracks, peak strength, porosity, proportion of detrimental minerals, etc. Porosity is reportedly of a devastating impact on the peak strength of igneous rocks. The quartz diorite rock samples in this study were selected from five quarries in Natanz, Iran and subject to microscopic and geomechanical investigations. The level of alteration and the minerals detrimental to the strength of the samples were identified from thin sections. Therefore, the geomechanical tests upon density, porosity, durability index, the Brazilian, and triaxial tests were conducted as per ISRM standards. The findings from microscopic studies reveal that alteration is of more intense impact on rock peak strength compared to that of porosity. The results were compared to standard values and a qualitative correlation between strength and microscopic properties was detected accentuating the importance of microscopic studies on construction stones. The correlation thereupon may be adopted in the exploration, exploitation, and process of construction stones to avoid heavy expenditures and damage to the environment.

  6. Defining and systematic analyses of aggregation indices to evaluate degree of calcium oxalate crystal aggregation

    Science.gov (United States)

    Chaiyarit, Sakdithep; Thongboonkerd, Visith

    2017-12-01

    Crystal aggregation is one of the most crucial steps in kidney stone pathogenesis. However, previous studies of crystal aggregation were rarely done and quantitative analysis of aggregation degree was handicapped by a lack of the standard measurement. We thus performed an in vitro assay to generate aggregation of calcium oxalate monohydrate (COM) crystals with various concentrations (25-800 µg/ml) in saturated aggregation buffer. The crystal aggregates were analyzed by microscopic examination, UV-visible spectrophotometry, and GraphPad Prism6 software to define a total of 12 aggregation indices (including number of aggregates, aggregated mass index, optical density, aggregation coefficient, span, number of aggregates at plateau time-point, aggregated area index, aggregated diameter index, aggregated symmetry index, time constant, half-life, and rate constant). The data showed linear correlation between crystal concentration and almost all of these indices, except only for rate constant. Among these, number of aggregates provided the greatest regression coefficient (r=0.997; pr=0.993; pr=‑0.993; pr=0.991; p<0.001 for both). These five indices are thus recommended as the most appropriate indices for quantitative analysis of COM crystal aggregation in vitro.

  7. Evaluation of possibilities of the plastic stone masonry of carbonate rocks in Slovakia

    Directory of Open Access Journals (Sweden)

    Peter Ružička

    2006-09-01

    Full Text Available At plastic processing of rocks, the size of mine blocks,is not decisive but aesthetically interesting textural and coloured parts of raw materials. Technologically are compact positions of travertine with a stripe texture, originating from the Hradišťa pod Vrátnom. An attractive raw material for the production of artificial jewelleries are onyx marbles from the Levice surrouting. In Spišské Podhradie honey-yellow stripy aragonite fills travertine rifts, suitable for the production of jewelleries. A small ornamental ware can also be produced from the compact travertine in Vyšné Ružbachy. A contrast textural arain of crinoid limestones from Krivoklát represents a quality raw material for the production of decorative plastics and jewelleries. The locality Prihradzany-Skalka provides guttenstein limestones, appropriate for the production of bigger plastics and utility articles. Aesthetically stand out articles from hallstatt limestones from Silická Brezová. For the figural treatment and the production of utility articles are suitable čorštynske limestones from the depositg Marmont - Stará Ľubovňa. The most widely used decorative stones are marbles from Tuhár. The interesting are pseudobreccias textures of the recrystallize wetterstein limestones from Tisovec. Marbles from Rákoš have variable colours. For the production of plastics are suitable streaked marbles from Lubeník. Positive results from the technological standpoint have locaties of carbonate rocks.

  8. Performance evaluation of stone matrix asphalt using indonesian natural rock asphalt as stabilizer

    Directory of Open Access Journals (Sweden)

    Nyoman Suaryana

    2016-09-01

    Full Text Available One type of road pavement material which is developed to be more resistant to permanent deformation is the SMA (Stone Matrix Asphalt. Utilization of the SMA mix in Indonesia has constraints in gain stabilizer and also difficulty to comply the gradations, mainly because it needs a relatively large amount of filler. Alternative of local materials that can be used is asbuton (natural rock asphalt from Buton Island. Asbuton is expected to act as a stabilizer and simultaneously provides an additional filler. The objective of this research is to evaluate the performance of the SMA that uses the asbuton. The methodology used in this research is the experimental method, its starts from material testing, design mix and performance testing that includes dynamic modulus, permanent deformation and fatigue resistance. The results obtained showed asbuton can prevent asphalt draindown as well as increase the proportion of filler. Draindown asphalt can be prevented by using binder absorbers with fiber cellulose and viscosity boosters with asbuton. Asbuton (LGA 50/25 can behave as a stabilizer as well as cellulose fiber. Addition of asbuton also improves the performance of the SMA mix, as shown with increase in the value of dynamic stability. In terms of resistance to fatigue, SMA with cellulosa as stabilizer and SMA with asbuton as stabilizer, relatively have the same performance. Master curve of dynamic modulus indicates SMA with asbuton as stabilizer is relatively stiffer at high temperatures (more than 4.4 °C, but relatively less stiff (less brittle at low temperatures. Keywords: Stone matrix asphalt, Asbuton, Draindown, Dynamic modulus, Permanent deformation

  9. Mineral resource of the month: dimension stone

    Science.gov (United States)

    Dolley, Thomas P.

    2012-01-01

    The article offers information on dimension stone (DS) that are quarried as natural rock for a specific size and dimension chosen for its color, strength, durability. Varieties of metamorphic, igneous or sedimentary rocks are used but DS rocks are mainly marble, granite and slate that can be found from Maine to Alabama in the U.S., in the Carrara District of Italy as well as in Greece, China and Brazil. It also notes the advent of steel and concrete in construction that ceased the use of DS.

  10. Novelda Stone: widely used within the Spanish architectural heritage

    Directory of Open Access Journals (Sweden)

    Fort, R.

    2002-06-01

    Full Text Available Novelda Stone is a calcareous rock, of the biocalcarenite type. It is extracted from the «Vinalopó Medio» area (Alicante, eastern Spain. Novelda stone is known as construction material from the 13th century. From final of the 19th century until the present time, it has been used in Madrid, Valencia and Alicante. In the past, the main quarries from which this type of rock was extracted were located in the municipal districts of Monóvar (Almorquí Stone, Sax (Portazgo Stone and Elda (Bateig Stone. Nowadays, the main active extraction site is situated in the Bateig Hill quarries. The rock extracted is known commercially as Bateig Stone. The main varieties of this Bateig Stone are: White, Blue, Layer and Fantasy. Each variety of Novelda stone has different durability rate and different pathology depending on their characteristics, particularly on their hydric behaviour patterns. Layer Bateig and Portazgo stone undergo granular disintegration and alveolization and are less durable than the rest. White and Blue Bateig, as well as Almorquí stone, only develop fissures or scaling under extreme conditions.

    La Piedra de Novelda es una roca carbonática del tipo biocalcarenita. Se extrae del área de Vinalopó Medio (Alicante, España oriental. La piedra de Novelda es conocida como material de construcción desde el siglo XIII. Desde finales del siglo XIX hasta la actualidad, se ha utilizado en edificios y monumentos de Madrid y Valencia, así como Alicante. En el pasado, las canteras principales donde se extrajo este tipo de piedra se localizaban en los distritos municipales de Monóvar (Piedra Almorquí, Sax (Piedra Portazgo y El da (Piedra Bateig. Hoy en día, la actividad principal se sitúa en las canteras de Bateig. La piedra extraída es conocida comercialmente como Piedra Bateig. Las variedades principales de esta Piedra Bateig son: Blanco, Azul, Llano y Fantasía. Consecuencia de las diferentes propiedades y en especial de los

  11. An overview of aggregate resources in the United States

    Science.gov (United States)

    Langer, William H.; Scott, P.W.; Bristow, C.M.

    2002-01-01

    In 2000 the USA produced about 2.7 billion tonnes of aggregate worth about $13.7 billion. Both crushed stone and sand and gravel are produced in virtually every State, although limited quantities are available in the Gulf Coastal Plain, the Colorado Plateau , the Wyoming Basin and the Great Plains. Prices vary depending on the product and location. Most aggregates are transported by road, and minor amounts by railroad, barge on navigable inland channels, and through the Great Lake ports. Imports and exports of aggregates are very minor. A major amount f crushed stone aggregates is consumed by concrete aggregate. Recycled aggregates account for about 8% of total demand, although the amount recycled is thought to be increasing. Current issues facing the inductry unclude the differences in quality specifications between States, adjusting to the increasing concern for the impact of aggregate mining on the environmentm, health issues from particulate matter and crystalline silica, and the complexity of obtaining permits for extraction. Redcustion in the number od companies extracting aggregrates is likely to occur through acquisitions.

  12. Fire effects on rock images and similar cultural resources [Chapter 5

    Science.gov (United States)

    Roger E. Kelly; Daniel F. McCarthy

    2012-01-01

    Throughout human global history, people have purposely altered natural rock surfaces by drilling, drawing, painting, incising, pecking, abrading and chiseling images into stone. Some rock types that present suitable media surfaces for these activities are fine-grained sandstones and granites, basalts, volcanic tuff, dolomites, and limestones. Commonly called rock...

  13. Geological-Technical and Geo-engineering Aspects of Dimensional Stone Underground Quarrying

    Science.gov (United States)

    Fornaro, Mauro; Lovera, Enrico

    Underground exploitation of dimensional stones is not a novelty, being long since practised, as proved by a number of historical documents and by a certain number of ancient quarrying voids throughout the world. Anyway, so far, open cast quarrying has been the most adopted practice for the excavation of dimensional stones. One primary reason that led to this situation is of course connected to the lower production costs of an open cast exploitation compared to an underground one. This cheapness has been supported by geological and technical motives: on the one hand, the relative availability of surface deposits and, on the other, the development of technologies, which often can be used only outdoor. But, nowadays, general costs of quarrying activities should be re-evaluated because new, and often proper, restrictions have been strongly rising during recent years. As a consequence of both environmental and technical restrictions, pressure will more and more arise to reduce open cast quarrying and to promote underground exploitations. The trend is already well marked for weak rocks - for instance in the extractive basin of Carrara, where about one hundred quarries are active, 30 per cent is working underground, but also in Spain, Portugal and Greece the number of underground marble quarries is increasing - but not yet for hard rock quarrying, where only few quarries are working underground all around the world. One reason has to be found in cutting technologies traditionally used. In weak rocks, diamond wire saw and chain cutter are usable, with few adaptations, in underground spaces, while drilling and blasting, the traditional exploitation method for hard stone, is not easily usable in a confined space, where often only one free face is available. Many technicians and researchers agree that two technologies will probably open the door to underground quarrying in hard rocks: diamond wire and water jet. The first one is already available; the second should still be

  14. Radon health hazards of some rocks of Iranian origin, frequently used as building stones

    International Nuclear Information System (INIS)

    Noori, H.; Ranjbar, A.H.

    2011-01-01

    Radon exhalation rate from various types of stones, used inside the living buildings, is a major factor for evaluation of the environmental radon level. To verify the significance and lethal impacts of this unknown and obscure source of radiation upon the people around the world, the exhaled radon gas concentrations from the rocks, granodiorite, granite, limestone and aragonite, and the effect of their block sizes on the exhalation rate, have been studied. The block samples, collected from their ores, were transferred to plastic containers in which the CR-39 detectors could properly be placed and air tightened, for concentration measurements. The results show the radon concentration of 7.4 ± 0.8, 6.6 ± 0.6, 0.08 ± 0.02 and 0.09 ± 0.02 kBq m -3 for granodiorite, granite, limestone and aragonite, respectively. The corresponding annual dose values in a closed environment are: 186 ± 20, 166 ± 15, 2.5 ± 1 and 2 ± 1 mSv y -1 . These absorbed dose values indicate that granodiorite and granite when used inside the buildings could increase the risk of various cancers while aragonite and limestone have much lower risks and are recommended for use inside the buildings. The former ones when used in the closure areas remedial action should be implemented. The results do not show obvious dependence between the rock size of the samples and their radon exhalation rate. (author)

  15. Operational features of decorative concrete

    Science.gov (United States)

    Bazhenova, Olga; Kotelnikov, Maxim

    2018-03-01

    This article deals with the questions of creation and use of decorative and finishing concrete and mortar. It has been revealed that the most effective artificial rock-imitating stone materials are those made of decorative concrete with the opened internal structure of material. At the same time it is important that the particles of decorative aggregate should be distributed evenly in the concrete volume. It can be reached only at a continuous grain-size analysis of the aggregate from the given rock. The article tackles the necessity of natural stone materials imitation for the cement stone color to correspond to the color of the rock. The possibility of creation of the decorative concrete imitating rocks in the high-speed turbulent mixer is considered. Dependences of durability and frost resistance of the studied concrete on the pore size and character and also parameters characterizing crack resistance of concrete are received.

  16. Long-distance stone transport and pigment use in the earliest Middle Stone Age

    Science.gov (United States)

    Brooks, Alison S.; Yellen, John E.; Potts, Richard; Behrensmeyer, Anna K.; Deino, Alan L.; Leslie, David E.; Ambrose, Stanley H.; Ferguson, Jeffrey R.; d’Errico, Francesco; Zipkin, Andrew M.; Whittaker, Scott; Post, Jeffrey; Veatch, Elizabeth G.; Foecke, Kimberly; Clark, Jennifer B.

    2018-04-01

    Previous research suggests that the complex symbolic, technological, and socioeconomic behaviors that typify Homo sapiens had roots in the middle Pleistocene methods. Hominins at these sites made prepared cores and points, exploited iron-rich rocks to obtain red pigment, and procured stone tool materials from ≥25- to 50-kilometer distances. Associated fauna suggests a broad resource strategy that included large and small prey. These practices imply notable changes in how individuals and groups related to the landscape and to one another and provide documentation relevant to human social and cognitive evolution.

  17. Terahertz lens made out of natural stone.

    Science.gov (United States)

    Han, Daehoon; Lee, Kanghee; Lim, Jongseok; Hong, Sei Sun; Kim, Young Kie; Ahn, Jaewook

    2013-12-20

    Terahertz (THz) time-domain spectroscopy probes the optical properties of naturally occurring solid aggregates of minerals, or stones, in the THz frequency range. Refractive index and extinction coefficient measurement reveals that most natural stones, including mudstone, sandstone, granite, tuff, gneiss, diorite, slate, marble, and dolomite, are fairly transparent for THz frequency waves. Dolomite in particular exhibits a nearly uniform refractive index of 2.7 over the broad frequency range from 0.1 to 1 THz. The high index of refraction allows flexibility in lens designing with a shorter accessible focal length or a thinner lens with a given focal length. Good agreement between the experiment and calculation for the THz beam profile confirms that dolomite has high homogeneity as a lens material, suggesting the possibility of using natural stones for THz optical elements.

  18. Fresh and mechanical properties of self-compacting concrete with coarse aggregate replacement using Waste of Oil Palm Shell

    Science.gov (United States)

    Prayuda, Hakas; Saleh, Fadillawaty; Ilham Maulana, Taufiq; Monika, Fanny

    2018-05-01

    Self-compacting Concrete (SCC) is a real innovation that can solidify itself without the help of tools to ease field practice. In its implementation, SCC can use alternative materials to reduce waste, such as Oil Palm Shell (OPS). In this research, OPS used as a replacement of crushed stone as the main coarse aggregate. The concrete mixture used consists of cement, sand, crushed stone, OPS as a variation of aggregate substitutes, palm oil fuel ash, and superplasticizer. OPS used were variated with 0%, 5%, 10%, 25% and 50% of crushed stone aggregate weight with age up to 28 days. Tests were conducted on fresh and mechanical properties. From the results, it is known that replacement of aggregate using OPS meets fresh properties criteria and although the compressive strength of OPS concrete mixture is lower than normal SCC, OPS still can be an alternative in making SCC and reducing palm oil industrial waste.

  19. Anisotropy indices and the effects on the hydric behaviour of natural stone

    Science.gov (United States)

    Fort, Rafael; Alvarez de Buergo, Monica; Varas, Maria Jose; Gomez-Heras, Miguel

    2010-05-01

    Building stone is an anisotropic material. Each type of rock (granite, limestone, slate, marble, etc.) has a different anisotropy, which is related to its own geological history, i.e. formation conditions and alteration processes. Knowing the anisotropy of natural stone is a matter of interest for determining the most adequate way to extract it from the quarry, for a better use during its manufacture or processing, to determine the quality of elements to be used as ashlars/masonry or as ornamental elements carving, as well to their arrangement in a structure. At the same time, materiaĺs anisotropy will condition the placing of, for instance, anchorages in dressing stone slabs. Anisotropy of natural stone controls water entry and its mobility, together with atmospheric pollutantśs, processes that favour the stone decay in building works, mainly those that shows a marked directional component, as it is the case of capillary water absorption. Water tends to be absorbed differently along the distinct main anisotropy directions, which are principally marked due to the arrangement and distribution of porosity in the rock. The aim of this study is to perform a comparative analysis of the various anisotropy indices commonly used when dealing with natural stone, determined by ultrasonic propagation techniques, in order to establish how anisotropy (by means of these indices) affect the process of capillary water absorption. Different type of natural stones have been selected, according to their traditional use for the construction of buildings in the region of Madrid (Spain). Their petrophysical properties have been determined (density, porosity, water absorption, etc), as well as ultrasonic transmission velocity has been measured along the three spatial directions of the test specimens (from 50 to 100 for each petrological type). According to this, the stone specimens were classified in different anisotropy levels or classes. Results show that stones with the highest

  20. Advances in elemental imaging of rocks using the AGLAE external microbeam

    Energy Technology Data Exchange (ETDEWEB)

    Calligaro, T., E-mail: thomas.calligaro@culture.gouv.fr [Centre de Recherche et de Restauration des musees de France, CNRS UMR171, Palais du Louvre, 75001 Paris (France); Coquinot, Y.; Pichon, L.; Moignard, B. [Centre de Recherche et de Restauration des musees de France, CNRS UMR171, Palais du Louvre, 75001 Paris (France)

    2011-10-15

    Rocks are widely represented in cultural heritage materials. They constitute the major part of archaeological artefacts like stone carvings, tools and weapons, and are present in art works in various forms, such as precious stone inlays or paint pigments. The study of such geomaterials, which are usually constituted of a complex aggregate of mineral phases, aims at determining their exact nature, their provenance and at understanding their possible alteration. Since minerals are often composed of light elements, IBA techniques such as PIXE and PIGE, thanks to their ability to measure with high sensitivity elements down to lithium, should be well adapted to their analysis. However, the bulk composition classically obtained using macro-IBA on pelletized samples or using a broad beam hides the multi-phased nature of the rocks and considerably blurs the searched chemical fingerprint. In contrast, the small size of a nuclear microprobe allows imaging the chemical composition at a finer scale and, when implemented in air, appears ideally suited to analyse without sampling these often precious items. This paper illustrates chemical micro-imaging of rocks with examples performed with the AGLAE external nuclear microprobe: characterisation of microscopic inclusions in gems and detailed chemical mapping of rocks with special emphasis to lapis lazuli. Lapis lazuli is of particular interest in both archaeology and art history: after being employed in Asia since the 7th millennium BC to make carvings and beads, it was used in Medieval Europe as a precious blue painting pigment known as ultramarine. The chemical imaging of major and trace elements in lapis lazuli using external {mu}-PIXE has permitted to identify its mineral phases, to assign their trace elements and to evidence undetected elements. In combination with {mu}-XRD and {mu}-Raman spectrometry, this approach provides a clear mineralogical fingerprint useful to determine rock provenance and to authenticate artefacts

  1. Advances in elemental imaging of rocks using the AGLAE external microbeam

    International Nuclear Information System (INIS)

    Calligaro, T.; Coquinot, Y.; Pichon, L.; Moignard, B.

    2011-01-01

    Rocks are widely represented in cultural heritage materials. They constitute the major part of archaeological artefacts like stone carvings, tools and weapons, and are present in art works in various forms, such as precious stone inlays or paint pigments. The study of such geomaterials, which are usually constituted of a complex aggregate of mineral phases, aims at determining their exact nature, their provenance and at understanding their possible alteration. Since minerals are often composed of light elements, IBA techniques such as PIXE and PIGE, thanks to their ability to measure with high sensitivity elements down to lithium, should be well adapted to their analysis. However, the bulk composition classically obtained using macro-IBA on pelletized samples or using a broad beam hides the multi-phased nature of the rocks and considerably blurs the searched chemical fingerprint. In contrast, the small size of a nuclear microprobe allows imaging the chemical composition at a finer scale and, when implemented in air, appears ideally suited to analyse without sampling these often precious items. This paper illustrates chemical micro-imaging of rocks with examples performed with the AGLAE external nuclear microprobe: characterisation of microscopic inclusions in gems and detailed chemical mapping of rocks with special emphasis to lapis lazuli. Lapis lazuli is of particular interest in both archaeology and art history: after being employed in Asia since the 7th millennium BC to make carvings and beads, it was used in Medieval Europe as a precious blue painting pigment known as ultramarine. The chemical imaging of major and trace elements in lapis lazuli using external μ-PIXE has permitted to identify its mineral phases, to assign their trace elements and to evidence undetected elements. In combination with μ-XRD and μ-Raman spectrometry, this approach provides a clear mineralogical fingerprint useful to determine rock provenance and to authenticate artefacts of

  2. Aggregates from mineral wastes

    Directory of Open Access Journals (Sweden)

    Baic Ireneusz

    2016-01-01

    Full Text Available The problem concerning the growing demand for natural aggregates and the need to limit costs, including transportation from remote deposits, cause the increase in growth of interest in aggregates from mineral wastes as well as in technologies of their production and recovery. The paper presents the issue related to the group of aggregates other than natural. A common name is proposed for such material: “alternative aggregates”. The name seems to be fully justified due to adequacy of this term because of this raw materials origin and role, in comparison to the meaning of natural aggregates based on gravel and sand as well as crushed stones. The paper presents characteristics of the market and basic application of aggregates produced from mineral wastes, generated in the mining, power and metallurgical industries as well as material from demolished objects.

  3. Artificial porous stone from of ornamental rock waste adaptable for civil construction and heritage restoration; Piedra artificial porosa a partir de residuos de rocas ornamentales adaptable a obras de construcción y restauración patrimonial

    Energy Technology Data Exchange (ETDEWEB)

    Durán Suárez, J.A.; García Casco, A.

    2017-09-01

    The technique of volumetric reintegration in severely deteriorated stone materials is of major importance for the restoration of architectural heritage. In using mortars for restoration it is important to control aspects such as the colour and textural similarity in relation to the adjacent stone, minor or equal strength and equal or greater porosity/permeability with respect to the original stone. This latter aspect is of particular complexity because the percentage distribution of pore-size ranges should not differ from that of the original stone material. The invention patent (with numbers of publication ES2187245 A1 and B1 16. 06. 2004), owned by the University of Granada, allows the production of excellent porous stones for decorative work in construction and mortar for restoration of stone materials with controlled porosity. Both materials consist of ornamental rock waste, so that a particular recycling purpose is given to this type of material which is difficult to reuse. In this paper we present the manufacturing process of these artificial stones and porous mortars with decorative and restorative purposes, from the controlled mixture of aggregates of ornamental rocks, organic and inorganic binders and generators of porosity. Once the curing and hardening has been done it is worth noting that one of the most important aspects of the product is the generation of a complex connected porous system as a result of the incorporation of crushed expanded polystyrene, which is activated after hardening through the application of organic solvents. [Spanish] La restauración arquitectónica patrimonial emplea la técnica de reintegración volumétrica en los soportes pétreos gravemente deteriorados. En la utilización de morteros de restauración y recrecido se requiere controlar aspectos importantes como: similitud cromática y textural respecto del entorno pétreo adyacente, menor o igual resistencia mecánica e igual o mayor porosidad/permeabilidad, respecto a la

  4. Choosing between a rock and a hard place: Camouflage in the round-tailed horned lizard Phrynosoma modestum

    Directory of Open Access Journals (Sweden)

    William E. COOPER, Jr., Wade C. SHERBROOKE

    2012-08-01

    Full Text Available The round-tailed horned lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modestum and its dependence on stones by placing a lizard in one of two microhabitats (uniform sand or sand with surface rocks approximately the same size as lizards. An observer who knew which microhabitat contained the lizard was asked to locate the lizard visually. Latency to detection was longer and probability of no detection within 60 s was higher for lizards on rock background than on bare sand. In arenas where lizards could choose to occupy rock or bare sand, much higher proportions selected rocky backgrounds throughout the day; at night all lizards slept among stones. A unique posture gives P. modestum a rounded appearance similar to many natural stones. Lizards occasionally adopted the posture, but none did so in response to a nearby experimenter. Stimuli that elicit the posture are unknown. That P. modestum is better camouflaged among rocks than on bare sand and prefers to occupy rocky areas suggests that special resemblance to rocks (masquerade enhances camouflage attributable to coloration and immobility [Current Zoology 58 (4: 541–548, 2012].

  5. Study on Excitation-triggered Damage Mechanism in Perilous Rock

    Science.gov (United States)

    Chen, Hongkai; Wang, Shengjuan

    2017-12-01

    Chain collapse is easy to happen for perilous rock aggregate locating on steep high slope, and one of the key scientific problems is the damage mechanism of perilous rock under excitation action at perilous rock rupture. This paper studies excitation-triggered damage mechanism in perilous rock by wave mechanics, which gives three conclusions. Firstly, when only the normal incidence attenuation spread of excitation wave is considered, while the energy loss is ignored for excitation wave to spread in perilous rock aggregate, the paper establishes one method to calculate peak velocity when excitation wave passes through boundary between any two perilous rock blocks in perilous rock aggregate. Secondly, following by Sweden and Canmet criteria, the paper provides one wave velocity criterion for excitation-triggered damage in the aggregate. Thirdly, assuming double parameters of volume strain of cracks or fissures in rock meet the Weibull distribution, one method to estimate micro-fissure in excitation-triggered damage zone in perilous rock aggregate is established. The studies solve the mechanical description problem for excitation-triggered damage in perilous rock, which is valuable in studies on profoundly rupture mechanism.

  6. Regional and detailed research studies for stone resources in Korea

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    This report consists of 7 articles. 1) Detail drilling research works on granodiorite stock of Cheanan area near Onyang city in Chungnam province. 2) Regional research studies on granites distributed in Kimje - Jeongeup. 3) Regional survey and feasibility study on diorite rock mass in Kohyeng, Cheonnam province. 4) Regional research study on the stone resources of Hamyang area. 5) A study on variation trends of physical properties of 5 kinds of building stone by means of Weather-Ometer experiment. 6) Borehole radar survey at the granodiorite quarry mine, Cheonan, Chungnam province. 7) Radar velocity tomography in anisotropic media. (author). refs., tabs., figs.

  7. Rock Directed Breaking Under the Impulse Load

    Science.gov (United States)

    Khomeriki, Sergo; Mataradze, Edgar; Chikhradze, Nikoloz; Losaberidze, Marine; Khomeriki, Davit; Shatberashvili, Grigol

    2016-10-01

    In the work the problem of directed chipping of facing stone material by means of managing of explosion process is considered. The technology of the mining of decorative stone by the use of explosion energy means the very rapid transfer of potential energy of elastic deformations to kinetic energy. As a result, the explosion impulse, in the expanse of the inertia of rock massive, does not cause the increase of existing cracks. In the course of explosion, the shock wave is propagated by ultrasonic velocity and in this case the medium parameters (pressure, density, temperature, velocity) increase in spurts. In spite of this fact the all three conservation laws of mechanics remain valid on basis of three laws the equations are derived by which the parameters of shock wave may be defined by means of the rock physical-mechanical properties. The load on the body volume at breaking under explosion acts over very small period of the time. Therefore, stressed-deformed state of the rock was studied when the impulse load acts on the boundary. It was considered that the mining of the blocks of facing stone is performed from the hard rocks. This means that the breaking proceeds in the zone of elastic deformation. In the conditions of mentioned assumptions, the expression of the stress tensor and displacement of vector components initiated by stressed-deformed state in the rock are written.

  8. Rock breaking methods to replace blasting

    Science.gov (United States)

    Zhou, Huisheng; Xie, Xinghua; Feng, Yuqing

    2018-03-01

    The method of breaking rock by blasting has a high efficiency and the cost is relatively low, but the associated vibration, flyrock, production of toxic gases since the 1970’s, the Western developed countries began to study the safety of breaking rock. This paper introduces different methods and their progress to safely break rock. Ideally, safe rock breaking would have little vibration, no fly stone, and no toxic gases, which can be widely used in municipal engineering, road excavation, high-risk mining, quarrying and complex environment.

  9. Evidence suggesting a genetic contribution to kidney stone in northeastern Thai population.

    Science.gov (United States)

    Sritippayawan, Suchai; Borvornpadungkitti, Sombat; Paemanee, Atchara; Predanon, Chagkrapan; Susaengrat, Wattanachai; Chuawattana, Duangporn; Sawasdee, Nunghathai; Nakjang, Sirintra; Pongtepaditep, Suttikarn; Nettuwakul, Choochai; Rungroj, Nanyawan; Vasuvattakul, Somkiat; Malasit, Prida; Yenchitsomanus, Pa-thai

    2009-06-01

    Genetic factor may play a role in the pathogenesis of kidney stone that is found in the northeastern (NE) Thai population. Herein, we report initial evidence suggesting genetic contribution to the disease in this population. We examined 1,034 subjects including 135 patients with kidney stone, 551 family members, and 348 villagers by radiography of kidney-ureter-bladder (KUB) and other methods, and also analyzed stones removed by surgical operations. One hundred and sixteen of 551 family members (21.05%) and 23 of the 348 villagers (6.61%) were affected with kidney stone. The relative risk (lambda(R)) of the disease among family members was 3.18. Calcium stones (whewellite, dahllite, and weddellite) were observed in about 88% of stones analyzed. Our data indicate familial aggregation of kidney stone in this population supporting that genetic factor should play some role in its pathogenesis. Genetic and genomic studies will be conducted to identify the genes associated with the disease.

  10. Effect of temperature on the containment properties of argillaceous rocks: The case study of Callovo-Oxfordian clay-stones

    International Nuclear Information System (INIS)

    Savoye, S.; Goutelard, F.; Beaucaire, C.; Charles, Y.; Fayette, A.; Herbette, M.; Larabi, Y.; Coelho, D.

    2011-01-01

    Heat generated by high level radioactive wastes could alter the performance of a clay repository. It was intended to investigate the effect of such a thermal period on the diffusive properties of Callovo-Oxfordian clay-stones. Thus, through-diffusion experiments with HTO, 36 Cl, 22 Na and 137 Cs were performed before, during and after stages of heating at 80 degrees C that lasted for up to one year. A special attention was paid to limit the occurrence of any chemical disturbance. Therefore (i) the temperature was raised to 80 degrees C, then progressively brought back to 21 degrees C, thanks to three intermediate temperature stages, and (ii) specific synthetic solutions were used for each temperature, chemistry of which being close to the equilibrium state, especially with respect to the carbonate and sulphate minerals. It was found that experiments carried out at 80 degrees C showed a clear increase of the effective diffusion coefficient values for the four tracers with respect to those obtained at 21 degrees C (by a factor of 3 for HTO and 36 Cl, 5 for 22 Na and 2 for 137 Cs). On the other hand, the porosity and rock capacity values did not exhibit any significant discrepancy between 21 degrees C and 80 degrees C, indicating no observable damage of both the pore conducing network and the sorption properties of clay minerals. The Stokes-Einstein relationship, based on the temperature dependency of the viscosity of bulk water, could be used to describe the temperature dependence of the diffusion of HTO and 36 Cl but failed to describe the diffusive evolution of the two sorbing cations, 22 Na and 137 Cs. Furthermore, experiments performed after the thermal period led to diffusive properties well matching those obtained before heating. All these results suggest that at the lab scale the heating of rock samples would not alter the clay-stone containment properties. (authors)

  11. The "Global Heritage Stone Resource": Past, Present and Future

    Science.gov (United States)

    Cooper, Barry

    2013-04-01

    The "Global Heritage Stone Resource" designation arose in 2007 as a suggested mechanism to enhance international recognition of famous dimension stones. There were also many aspects of dimension stone study that had no formal recognition in mainstream geology and which could be recognised in a formal geological sense via an internationally acceptable geological standard. Such a standard could also receive recognition by other professionals and the wider community. From the start, it was appreciated that active quarrying would an important aspect of the designation so a designation different to any other standard was needed. Also the project was linked to the long-established Commission C-10 Building Stone and Ornamental Rocks of the International Association of Engineering Geology and the Environment (IAEG C-10). Since 2007, the "Global Heritage Stone Resource" (GHSR) proposal has evolved in both in stature and purpose due to an increasing number of interested international correspondents that were actively sought via conference participation. The "English Stone Forum" in particular was pursuing similar aims and was quick to advise that English dimension stone types were being recognised as having international, national or regional importance. Furthermore the proposed designation was suggested as to having significant value in safeguarding designated stone types whilst also providing a potential mechanism in preventing heritage stone replacement by cheap substitutes. During development it also became apparent that stone types having practical applications such as roofing slates and millstones or even stone types utilised by prehistoric man can also be recognised by the new designation. The heritage importance of architects was also recognised. Most importantly an international network evolved, primarily including geologists, that now seems to be the largest international grouping of dimension stone professionals. This has assisted the project to affiliate with the

  12. Evaluating the Rate of Stone Art Deterioration in Wadi Maghara and Wadi Mukattab, Sinai, Egypt

    Directory of Open Access Journals (Sweden)

    Sayed HEMEDA

    2012-06-01

    Full Text Available One of the key reasons for the status of Wadi Maghara and Wadi Mukattab as World Heritage Sites is the abundance of stone art present there. Unfortunately, in time, much of the stone art heritage in the two archaeological sites was lost, due to natural stone weathering processes, to static and dynamic actions and lately, due to the lack of preservation measures and to the action of people. That fragile art heritage is non-renewable and, therefore, it requires specialized management. Several stone facades in Wadi Maghara have embossed inscriptions of early rulers of Egypt, that document their expeditions to mine precious minerals, primarily turquoise and copper, that were found in the area. Wadi Mukattab (south of Wadi Maghara is the valley of inscriptions. Over a distance of 3 km along this valley inscriptions can be found on the mountain rocks that have mostly been made by Nabateans (2nd and 3rd Century but also by others, such as pilgrims, soldiers, merchants, throughout the centuries. In our case study, inscriptions from specific study areas were analyzed by using SEM, polarizing microscope, XRD, SEM with EDX, DTA-TGA, Grain Size Distribution, Pore Media Characterization and some stone samples were tested in the stone mechanics laboratory, to determine the physical and mechanical characteristics of the stone with carved inscriptions. Digital photographs were taken, with Geographic Information Systems software. Older images were compared with more recent ones and in order to classify and quantify the amount of deterioration that occurred over time. Various methodologies were applied to classify the images, and it was found that manual digitizing provided the best means for quantifying the amount of deterioration. Results showed that the damage was primarily caused due to the instability of stone structures, because of the extensive jointing and rock fall gravity, due to dynamic actions and the granular disaggregation of the stone surface. The

  13. Fire effects on flaked stone, ground stone, and other stone artifacts [Chapter 4

    Science.gov (United States)

    Krista Deal

    2012-01-01

    Lithic artifacts can be divided into two broad classes, flaked stone and ground stone, that overlap depending on the defining criteria. For this discussion, flaked stone is used to describe objects that cut, scrape, pierce, saw, hack, etch, drill, or perforate, and the debris (debitage) created when these items are manufactured. Objects made of flaked stone include...

  14. Electrical resistivity measurements to predict abrasion resistance of ...

    Indian Academy of Sciences (India)

    WINTEC

    increasing expansion of highway and other construction works and decreasing natural aggregate resources in the world, the demand for crushed stone aggregates has in- creased from day-to-day. One of the important properties of rock aggregates is abrasion resistance. The abrasion resistance of aggregates is generally ...

  15. Specification aggregate quarry expansion: a case study demonstrating sustainable management of natural aggregate resources

    Science.gov (United States)

    Langer, William H.; Tucker, M.L.

    2003-01-01

    Many countries, provinces, territories, or states in the European Union, Australia, Canada, the United States, and elsewhere have begun implementing sustainability programs, but most of those programs stop short of sustainable management of aggregate resources. Sustainable practices do not always have to be conducted under the title of sustainability. This case study describes how Lafarge, a large multinational construction materials supplier, implemented the principles of sustainability even though there was an absence of existing local government policies or procedures addressing sustainable resource management. Jefferson County, Colorado, USA, is one of three counties in the six-county Denver, Colorado, region that has potentially available sources of crushed stone. Crushed stone comprises 30 percent of the aggregate produced in the area and plays a major role in regional aggregate resource needs. Jefferson County is home to four of the five crushed stone operations in the Denver region. Lafarge operates one of those four quarries. Lafarge recently proposed to expand its reserves by exchanging company-owned land for existing dedicated open space land adjacent to their quarry but owned by Jefferson County. A similar proposal submitted about 10 years earlier had been denied. Contrary to the earlier proposal, which was predicated on public relations, the new proposal was predicated on public trust. Although not explicitly managed under the moniker of sustainability, Lafarge used basic management principles that embody the tenets of sustainability. To achieve the goals of sustainable aggregate management where no governmental policies existed, Lafarge not only assumed their role of being a responsible corporate and environmental member of the community, but also assumed the role of facilitator to encourage and enable other stakeholders to responsibly resolve legitimate concerns regarding the Lafarge quarry proposal. Lafarge successfully presented an enlightened

  16. The possibility of use of Kremicj granitoid (Serbia) as an architectural stone

    International Nuclear Information System (INIS)

    Kureshevicj, Lidja

    2010-01-01

    The stone from the granitoid pluton of Kremić in southern Serbia has been examined in order to evaluate the possibility of its use as an architectural stone. Both field observations and laboratory testing of specimens have been performed. Although the specimens were collected from the field surface level, their physicomechanical lab test results have shown that the rock mass itself fulfils all the requirements for use as an architectural stone set by the State through Serbian standards. Also, the stone quality is higher in deeper ground levels, where the weathering agents have less intense effects. This stone does not have high ornamental properties, but it has a finegrained texture and low mica content which has a positive effect on its technical characteristics and susceptibility to processing. (Author)

  17. Reliability of using nondestructive tests to estimate compressive strength of building stones and bricks

    Directory of Open Access Journals (Sweden)

    Ali Abd Elhakam Aliabdo

    2012-09-01

    Full Text Available This study aims to investigate the relationships between Schmidt hardness rebound number (RN and ultrasonic pulse velocity (UPV versus compressive strength (fc of stones and bricks. Four types of rocks (marble, pink lime stone, white lime stone and basalt and two types of burned bricks and lime-sand bricks were studied. Linear and non-linear models were proposed. High correlations were found between RN and UPV versus compressive strength. Validation of proposed models was assessed using other specimens for each material. Linear models for each material showed good correlations than non-linear models. General model between RN and compressive strength of tested stones and bricks showed a high correlation with regression coefficient R2 value of 0.94. Estimation of compressive strength for the studied stones and bricks using their rebound number and ultrasonic pulse velocity in a combined method was generally more reliable than using rebound number or ultrasonic pulse velocity only.

  18. Migration behavior and sorption mechanisms of radionuclides in sedimentary sand stones

    International Nuclear Information System (INIS)

    Tanaka, Tadao; Kamiyama, Hideo; Sriyotha, K.

    1993-05-01

    The influence of crushed particle size and weathering of sedimentary rock on migration behavior and sorption mechanisms of 60 Co, 85 Sr and 137 Cs has been investigated by using the fresh sand stones (classified into two particle size ranges of 1 ∼ 3 mm and 2 , KCl, NH 2 OH-HCl, K-oxalate and H 2 O 2 solutions were carried out, to elucidate their dominated sorption mechanisms. Distribution coefficient values of the all three radionuclides, Kds, for the sand stone of 1 ∼ 3 mm was smaller than that of 85 Sr, and the same irreversible sorptions as the selective sorption of Co onto manganese oxides and fixation of Cs by the layer silicate for 60 Co and 137 Cs, respectively. Larger sorbability of the weathered sand stone was explained to be related to an increase of amounts of the effective sorption site, such as cation exchangeable site, calcite, smectite and manganese oxides, which was possibly caused from metamorphism induced by weathering the fresh sand stone. (author)

  19. Evaluation of bedrock mainly composed of volcanic aggregate rocks at the Higashidori Nuclear Power Station

    International Nuclear Information System (INIS)

    Hashimoto, Shuichi; Miwa, Tadashi; Nishidachi, Masayuki

    2000-01-01

    When carrying out engineering evaluation on foundation bedrock for important constructions such as nuclear power station, dam, and so forth, it is required as a premise on carrying out various surveys, tests, and analyses to select adequate geological elements, to classify them to some groups capable of regarding as a common engineering property, and to rate them. On a hard bedrock, there is a classification method with relatively higher versatility adding condition of crack and weathering to performances at each site as an index, but on a soft one, most of its classification are carried out individually for its site in response to an index caused by the bedrock itself. Here were shown the results carried out some bedrock classifications on a base of grouping for rock sorts and rock phases, according to some concepts on a draft of the standard on the soft bedrock classification due to the nuclear engineering committee of the Japan Society of Civil Engineers, a reference draft on the soft bedrock classification of the 'Technical indications on seismic resistance design of the nuclear power station' of the Japan Electric Association, (JEAG4601-1987), and so forth. As a result applied the reference draft on the soft bedrock, and so forth to the bedrock at the Higashidori Nuclear Power Station composed of volcanic aggregate rocks of the Miocene epoch of the new Tertiary system, an adequate engineering evaluation was made possible by making grouping of rock sorts and rock phases to a foundation. And, on property evaluation of the quality changed vein, as a result of various tests, appropriate properties could be obtained. (G.K.)

  20. Property changes of urinary nanocrystallites and urine of uric acid stone formers after taking potassium citrate

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Guang-Na; Ouyang, Jian-Ming, E-mail: toyjm@jnu.edu.cn; Xue, Jun-Fa; Shang, Yun-Feng

    2013-10-15

    The property changes of urinary nanocrystallites in 20 cases of uric acid (UA) stone formers after 1 week of potassium citrate (K{sub 3}cit) intake were comparatively studied by X-ray diffraction analysis, Fourier transform infrared spectroscopy, nanoparticle size analysis, and transmission electron microscopy. Before K{sub 3}cit intake, the urinary crystallites mainly contained UA and calcium oxalate. After K{sub 3}cit intake, the components changed to urate and UA; the qualities, species, and amounts of aggregated crystallites decreased; urine pH, citrate, and glycosaminoglycan excretions increased; and UA excretion, Zeta potential, and crystallite size decreased. The stability of crystallites followed the order: controls > patients after taking K{sub 3}cit > patients before taking K{sub 3}cit. Therefore, the components of urinary stones were closely related to the components of urinary crystallites. - Graphical abstract: The relationships among stone components, urinary crystallite components, and urine pH were established. The crystallites stability order was: controls > patients after taking K{sub 3}cit > patients before taking K{sub 3}cit. Highlights: • Urine crystallite property of uric acid stone former after K{sub 3}cit intake was studied. • The components of crystallites in urine are closely related to type of stones. • After K{sub 3}cit intake the qualities and species of crystallites decreased. • After K{sub 3}cit intake the amount of aggregated crystallites decreased. • The stability of urinary crystallites of UA patients increased after taking K{sub 3}cit.

  1. Property changes of urinary nanocrystallites and urine of uric acid stone formers after taking potassium citrate

    International Nuclear Information System (INIS)

    Zhang, Guang-Na; Ouyang, Jian-Ming; Xue, Jun-Fa; Shang, Yun-Feng

    2013-01-01

    The property changes of urinary nanocrystallites in 20 cases of uric acid (UA) stone formers after 1 week of potassium citrate (K 3 cit) intake were comparatively studied by X-ray diffraction analysis, Fourier transform infrared spectroscopy, nanoparticle size analysis, and transmission electron microscopy. Before K 3 cit intake, the urinary crystallites mainly contained UA and calcium oxalate. After K 3 cit intake, the components changed to urate and UA; the qualities, species, and amounts of aggregated crystallites decreased; urine pH, citrate, and glycosaminoglycan excretions increased; and UA excretion, Zeta potential, and crystallite size decreased. The stability of crystallites followed the order: controls > patients after taking K 3 cit > patients before taking K 3 cit. Therefore, the components of urinary stones were closely related to the components of urinary crystallites. - Graphical abstract: The relationships among stone components, urinary crystallite components, and urine pH were established. The crystallites stability order was: controls > patients after taking K 3 cit > patients before taking K 3 cit. Highlights: • Urine crystallite property of uric acid stone former after K 3 cit intake was studied. • The components of crystallites in urine are closely related to type of stones. • After K 3 cit intake the qualities and species of crystallites decreased. • After K 3 cit intake the amount of aggregated crystallites decreased. • The stability of urinary crystallites of UA patients increased after taking K 3 cit

  2. The human impact on natural rock reserves using basalt, anorthosite, and carbonates as raw materials in insulation products

    DEFF Research Database (Denmark)

    Dahl, Tais Wittchen; Clausen, Anders U.; Hansen, Peter B.

    2011-01-01

    lithosphere or subducted with oceanic crust and recycled through the mantle by plate tectonics. Insulation products have a chemical composition similar to average crustal rocks and participate in the natural rock cycle. However, these products need not accumulate in nature, inasmuch as old insulation......Typical crustal rocks such as basalt, limestone, and anorthosite are used in stone wool insulation products. The raw materials for stone wool production are not specific to any rare mineral source but depend upon the mixture of materials having the correct chemical composition, exemplified by 40 wt......% basalt, 20 wt% anorthosite, and 40 wt% cement-bonded renewable materials. This study provides an overview of the natural cycle of these resources, including their abundances in nature, and sets the consumption by the stone wool industry and other human activities in perspective. Basalt, anorthosite...

  3. Magnesium-to-calcium ratio in tap water, and its relationship to geological features and the incidence of calcium-containing urinary stones.

    Science.gov (United States)

    Kohri, K; Kodama, M; Ishikawa, Y; Katayama, Y; Takada, M; Katoh, Y; Kataoka, K; Iguchi, M; Kurita, T

    1989-11-01

    We examined the relationship among magnesium and calcium content in tap water, the geological features and urinary stone incidence in Japan. The magnesium-to-calcium ratio in tap water correlated negatively with the incidence of urolithiasis. There was no correlation between calcium and magnesium concentration in tap water and urinary stone incidence. Geological features in Japan were classified into 5 groups. The magnesium-to-calcium ratio in the basalt areas was higher than in the other areas, while ratio in the granite areas was low. In the sedimentary rock areas calcium and magnesium concentrations were high; the magnesium-to-calcium ratio in these areas was between those of the basalt and granite areas. The limestone areas had a much higher calcium concentration. The incidence of urinary stones in the sedimentary rock and basalt areas was lower than that of the granite areas, while that in the limestone areas was the highest. Thus, the incidence of urinary stone is related to the magnesium-to-calcium ratio in tap water and the geological area.

  4. A study on the utilization of stone powder sludge (III)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chi Kwon; Sohn, Jeong Soo; Kim, Byung Gyu [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    This study was performed to activate the building stone industry by increasing the recycling amounts of waste resources and minimizing the generation of the environmental pollution materials. In order to utilize the waste stone and stone powder sludge generated from the domestic quarry and cutting process of stone plates, the manufacturing technology of the artificial stone plate as a building material was developed. Based on the first and second year results, this third-year study was performed for manufacturing the large-scale artificial stone plate of 500 x 500 x 20 mm. Also for applying these artificial stone plates to the flooring and interior materials in the building industry, the manufacture of the large-scale artificial stone plates with various patterns and colors was carried out by changing the species and the ratio of raw materials, amounts of binder and molding pressure. Artificial stone plate was composed of waste crushed stone, stone powder sludge and binder which was used for binding waste stone and rock powder each other. In order to investigate the physical properties of large-scale artificial stone, the measure of specific gravity, absorption ratio, P-wave velocity, compressive strength, tensile strength, Young`s modulus, and Poisson`s ratio were carried out. As a result of testing physical properties, there was no difference between small-scale artificial stone and large-scale one. At the optimum conditions it was shown that the properties of artificial stones were as follows, 2.32 of specific gravity, 0.33 of water-absorption ratio, 780 kg/cm{sup 2} of compressive strength and 98 kg/cm{sup 2} of tensile strength. Based on the above results, the preliminary economic estimation on the manufacture of the artificial stone plate was carried out. It was shown that the manufacturing cost of the artificial stone plate was 18,000 won/m{sup 2}, which was merely half that of natural stone plate, and the application of these on the building stone industry

  5. A study on the industrialization of building stones and industrial stone crafts - Study on the causes of stone contaminations

    Energy Technology Data Exchange (ETDEWEB)

    Hyun, Jeon Ki; Lee, Han Yeang [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    Causes of building stone contamination are acid rains in polluted areas, iron bearing minerals in stone itself, salts, sealants, cutting and grinding processes in stone factory and steel compounds structures such as stone anchors, bolts, rain culvert and guide frames. Contaminations on the building stone surface of Sejong culture center can be found around floor stones, stair stones, parterre stones, pillar stones and other outdoor stone panels. The parterre stones are contaminated by white tarnishes and rust flows are occurred on the surface of pillar stones and outdoor stone panels around entrance. Black tarnishes are cumulated on the pillar stones and other outdoor decorated stone panels and change the original granite color. Causes of building stone contaminations from Sejong culture center are wet method to attach stone panels, rust from steel compounds structures and air pollutants. Cement and mortar used from wet method react with sulfur dioxides in polluted air and from fine calcite crystals (white tarnish). Rusts from steel compounds structures such as rainwater culvert and steel guide frames can move to the stone surface by rain and leave rust flows on it. Pollutants (tar compounds, carbons, dusts, etc.) in air are cumulated with humidity on the stone surface and change color from white granite color to dusty dark color. Historical stone sculptures such as man and animal shaped stone crafts, tombstones, square stone tables in front of a tomb and guide and circumference stones around tomb in Royal Tombs (Donggu rung, Yung rung, Seoou rung and Hunin rung) distributed in Kyunggi province are contaminated by various moss and air pollutants and its original colors are deeply changed. (author). 21 refs., 11 tabs., 22 figs.

  6. Underground mining of aggregates. Main report

    OpenAIRE

    Brown, Teresa J.; Coggan, John S.; Evans, David J.; Foster, Patrick J.; Hewitt, Jeremy; Kruyswijk, Jacob B.; Smith, Nigel; Steadman, Ellie J.

    2010-01-01

    This report examines the economic feasibility of underground mining for crushed rock aggregates in the UK, but particularly in the London, South East and East of England regions (the South East area of England). These regions import substantial volumes of crushed rock, primarily from the East Midlands and South West regions, requiring relatively long transport distances to market for this bulk commodity. A key part of the research was to determine whether or not aggregate could be produced an...

  7. On the use of High-density rock in rubble Mound Breakwaters

    DEFF Research Database (Denmark)

    Helgason, Einar; Burcharth, H. F.

    2005-01-01

    Natural rock with high density is widely used in the Scandinavian countries. However, the use of natural rock with density higher than 2:9t=m3 is ordinarily associated with some kind of problem solving, e.g. where normal density stones have to be replaced with heavier stones without increasing th...... on stability from the increased density is overestimated by conventional armour stability formulae in case of steep slopes. The infuence of the density depends on the slope angle and the type of armour units....... the construction volume or layer thickness. Most common design formulae do not give a clear conclusion on the in°uence of the rock density on the stability. The present paper presents results of small and large scale model tests in which is used rock with different densities. It is shown that the positive effect...

  8. Swelling behaviour of stones and its interest in conservation. An appraisal

    Directory of Open Access Journals (Sweden)

    Delgado Rodrigues, J.

    2001-12-01

    Full Text Available Swelling can be defined as the volume increase experienced by any solid body when wetted. Many lithotypes (carbonate rocks, sandstones, igneous rocks have expansive components in their composition; anhydrite and clay minerals are the two best-known expansive components in stone materials. Swelling strain can be easily quantified and swelling pressure determination is accessible in many geotechnical laboratories. This paper deals with the decay of stone due to swelling of clays and discusses the ways to take the swelling behaviour into account when the assessment of stone durability is concerned. It analyses the role of swelling in stone conservation and reviews some cases where this decay mechanism has a relevant role, explicit or implicitly.

    La expansibilidad puede ser definida como el incremento de volumen que un cuerpo sólido experimenta cuando es humedecido. Muchos tipos litológicos (rocas carbonatadas, areniscas, rocas ígneas tienen componentes expansivos en su composición; la anhidrita y los minerales arcillosos son los dos componentes expansivos más conocidos. La expansibilidad puede ser medida con facilidad y la determinación de la presión de hinchamiento se puede efectuar en muchos laboratorios de geotecnia. Este trabajo trata del problema de la degradación de los materiales rocosos debida a la expansión de las arcillas y discute las formas de tenerla en cuenta cuando interesa evaluar la durabilidad de esos materiales. Se analiza el papel de la expansibilidad en la conservación de la piedra y se hace una revisión de algunos casos en los que la degradación por expansión tiene un papel relevante, explícito o implícito.

  9. The Suitability of Limestone from Pilaspi Formation (Middle-Late Eocene for Building Stone in Koya Area, NE Iraq

    Directory of Open Access Journals (Sweden)

    Hemn M. Omar

    2015-09-01

    Full Text Available Suitability of limestone rocks has a crucial importance when stones are used for constructing modern structure. The purpose of this study is to clarify the links between physical, mechanical properties of limestone rocks, also their quality to use as building materials. A total of six limestone rock samples were collected from three different outcrops locations within Pilaspi Formation in Koya area. Engineering geological and geotechnical properties of the limestone rocks in the study area were determined based on the field studies and laboratory tests. The field studies included observations/ measurements of rock mass characteristics such as color, grain size, orientation, bedding thickness and weathering state of the rock materials also spacing, persistence, roughness and infilling material of the discontinuities. Laboratory tests were carried out for determining water content, water absorption, density, uniaxial compressive strength, slake durability and porosity of the rock materials. The study results go well with the national and international standards (Iraqi Standards, 1989; American Society for Testing and Materials, 2004; International Society for Rock Mechanics, 1981 and have shown that the limestone rocks are acceptable for building stone.

  10. Microstructural characterization samples of Cariri stones

    International Nuclear Information System (INIS)

    Costa, D.L.; Fernandes, I.M.M.; Farias, R.M.C.; Braga, A.N.S.; Menezes, R.R.; Neves, G.A.

    2014-01-01

    Ornamental rocks are among the most promising areas of business in the mining sector, thus resulting in the need for addition of aesthetic beauty, there were investments in quality, safety and characterization in its various fields of application. Based on this, this paper aims to microstructural characterization of a class of these rocks: the Stones Cariri, also known as limestone, calcareous rocks that are composed primarily of calcium and magnesium carbonate, but may vary due its origin. For this, four samples were studied with two of the Apodi Plateau and two of the Araripe, which were characterized physically and structurally through micro testing, chemical analysis, X-ray diffraction, optical micrograph and porosimetry. The results show that calcitic and dolomitic lime is present porosity ranging from 5 to 15% of pores with a concentration between 100nm and 10mm and many microstructural heterogeneity. (author)

  11. Granodiorite - one of the most significant Slovenian natural stones

    Science.gov (United States)

    Kramar, Sabina; Trajanova, Mirka; Rogan-Šmuc, Nastja; Gutman, Maja; Bedjanič, Mojca; Mladenovič, Ana

    2015-04-01

    The paper provides a description of the petrographic and mechanical characteristics of granodiorite from the Pohorje Mountains (NE Slovenia) and of its use as a natural stone. This stone, which is a calc-alkaline igneous rock of Miocene age (18.7 Ma), is characterised by its grey colour and by its thick white aplite-pegmatite veins. It mainly consists of plagioclase, quartz, and K-feldspar, which are light coloured constituents, with biotite and a small amount of hornblende as dark coloured minerals. Some other minerals are found in traces, among which pyrite is considered to be the most problematic. However, due to the presence of a small amount of arsenic, the pyrite is quite stable and not prone to alteration. In Slovenia currently two quarries are located in granodiorite, both protected as valuable natural geological features; an active quarry at Cezlak which is the largest quarry in magmatic rocks in Slovenia and the abandoned quarry in Josipdol. Granodiorite is considered the highest quality natural stone in Slovenia. It is characterised by high density, low water absorption, and low open porosity, so that it exhibits high frost and salt resistance, as well as a high compressive strength and an extremely high flexural strength, which is due to its pronounced oriented structure. It is widely recognized throughout Slovenia by its durability and its decorative white veins, and is currently the most frequently used natural stone in Slovenia. It is mainly used as paving and cladding material for residential buildings, churches, and other structures, as well as for squares, thus giving a special character to many of Slovenia's largest towns and cities. Several important buildings are decorated by means of this stone, such as the Slovenian Parliament, the Republic Square business complex, the Maximarket department store, and the Faculty of Law of the University of Ljubljana, all of which are located in Ljubljana, some of them having been declared as cultural

  12. The Kolmården serpentine marble in Sweden, a building stone found at many levels in the society.

    Science.gov (United States)

    Wikström, Anders; Pereira, Dolores

    2013-04-01

    The Kolmården marble is a green serpentine marble of Svekofennian age (c. 1900 Ma). Serpentine is mainly secondary after diopside. The rock has been used as far back as in the 13th century. But it was mainly due to the start of the building of the Royal castles in Stockholm in the 17th century when the stone became more extensively used. The quarries were in operation until the 1970s and during the last years the production was so rationalized that one finds the stone in stairs, pavement and non structural ornaments within "common" houses all over the country. One can also find this stone in many exclusive places all over the world (e.g. the Paris Opera house, League of Nations building in Geneva, Leeds University Library, Uppsala University, Rockefeller Center, etc). The importance of this stone in international architecture, the good physical and mechanical behaviour observed in its emplacements and the possibilities for preservation of some of the quarries makes the Kolmården marble a good candidate as Global Stone Heritage Stone. The nomination will also trigger international publications on this natural stone to spread its knowledge among scientists and architects to be able to select this rock in case that some restoration on the mentioned important buildings is needed at some point.

  13. Radon exhalation rates from slate stone samples in Aravali Range in Haryana

    International Nuclear Information System (INIS)

    Upadhyay, S.B.; Kant, K.; Chakarvarti, S.K.

    2012-01-01

    The slate stone tiles are very popular in covering the walls of the rooms. Radon is released into ambient air from slate stones due to ubiquitous uranium and radium in them, thus increasing the airborne radon concentration. The radioactivity in slates stones is related to radioactivity in the rocks from which the slate stone tiles are formed. In the present investigation, the radon emanated from slate stone samples collected from different slate mines in Aravali range of hills in the Haryana state of Northern India has been estimated. For the measurement of radon concentration emanated from these samples, alpha-sensitive LR-115 type II plastic track detectors have been used. The alpha particles emitted from the radon form tracks in these detectors. After chemical etching the track density of registered tracks is used to calculate radon concentration and exhalation rates of radon using required formulae. The measurements indicate normal to some higher levels of radon concentration emanated from the slat stone samples collected from Aravali range of hills in north India. The results will be discussed in full paper. (author)

  14. Digitalization of the exceptional building and decorative stones collection of the Natural History Museum Vienna

    Science.gov (United States)

    Ferrière, Ludovic; Steinwender, Christian

    2014-05-01

    The Natural History Museum Vienna (NHMV) owns one of the largest building, decorative, and ornamental stones collections in Europe. This important collection dates back to the 19th century and was initiated by curator Felix Karrer after a donation of the "Union-Baugesellschaft" (Karrer, 1892). It contains rock samples used for the construction of most of the famous buildings and monuments in Vienna and in the entire Austria and surrounding countries, as well as from other famous constructions and antique (Egyptian, Greek, Roman, etc.) monuments in the world. Decorative stones that were used for the inside parts of buildings as well as artificial materials, such as stucco, tiles, and building-materials like gravel, are also part of this collection. Unfortunately, most specimens of this collection cannot be displayed at the NHMV (i.e., only 500 specimens are visible in the display Hall I) and are therefore preserved in storage rooms, and not accessible to the public. The main objective of our project of digitalization is to share our rock collection and all treasures it contains with the large majority of interested persons, and especially to provide knowledge on these rocks for people who need this information, such as people who work in cultural, architectural, scientific, and commercial fields. So far 4,500 samples from our collection have been processed with the support of the Open Up! project (Opening up the Natural History Heritage for Europeana). Our database contains all information available on these samples (including e.g., the name of the rock, locality, historic use, heritage utilization, etc.), high-quality digital photographs (with both top and bottom sides of the samples), and scanned labels (both "old" NHMV labels and other (original) labels attached to the samples). We plan to achieve the full digitalization of our unique collection within the next two years and to develop a website to provide access to the content of our database (if adequate

  15. The formation of separation cracks in the extraction of block stone

    Directory of Open Access Journals (Sweden)

    S.M. Stovpnik

    2017-12-01

    Full Text Available Currently, the undisputed leader of the destruction of strong rocks by mining as open-pit and underground mining is drilling and blasting method. The main disadvantage of this method is the seismic effect of the explosion to rock, the violation of their integrity, the development of cracks and weakening of the array. The most acute effect is visible while production of block materials, delineation of mine workings. The use of low-blasting explosives, cartridges and charges for special constructions allow us to reduce dynamic impact on blasthole area, however, their use leads to higher costs and in some cases does not provide the necessary end results. For example, in the extraction of block stone losses reach more than thirty percent. One of the possible ways of solving this problem is the use of static methods of destruction of rocks. Currently, a variety of ways of non-explosive destruction, in particular, mechanical methods are developed. Most of these methods are under research and design development. Their industrial use is hampered by lack of equipment, low reliability, high energy consumption, hazardous impact on human, high cost. All these drawbacks force to look for ways to create a cheap and promising way of cutting hard rocks. One of the perspective directions of the static fracture of rocks is the use of non-explosive destructive compositions of LDCs. The features of the management of cracking in holes in the separation of the stone blocks with the use of non-explosive destructive compositions (LDCs with industrial unit that contains control panels are analyzed. The conditions of crack growth of the split relative to the axes of anisotropy with the maximum or minimum strength are defined. The features of the control the direction of fracturing in boreholes in the separation of the stone blocks using a non-explosive mixtures destructive (LDCs with industrial units, which include the control panels are analyzed. The conditions of crack

  16. Radiological data on building stones from a Spanish region. Castilla y Leon

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, A.; Neves, L. [Coimbra Univ. (Portugal). Dept. Ciencias da Terra; Pereira, D.; Peinado, M.; Armenteros, I. [Salamanca Univ. (Spain). Dept. de Geologia

    2013-07-01

    As construction and building material, natural stone has a great potential to promote the commercial activities of certain European regions. Such is the case of Castilla y Leon in Spain, where many different rocks, ranging from sedimentary to metamorphic and igneous, are commercialized for building purposes. However, to be able to compete in a market subject to an economic crisis, highly exacerbated in the construction sector, and to compete with the lower prices offered by emerging countries, the issue would be to make the Spanish offer more attractive. Here we propose a complete characterization of rocks regarding their radiological properties, which are related to their mineralogy and geochemistry. Rocks emit natural radioactivity, and the presence of Rn and its decay products in dwellings has become an important issue in North America and Europe owing to its relationship with the carcinogenic effects of this gas. Although most of the studied rocks comply with the I parameter proposed in the European Norm 112 for Radiological Protection (accepted value I ≤ 1; average for sedimentary rock: I = 0.22, SD 0.14; average for metamorphic rocks: I = 0.70, SD 0.48; average for igneous rock: I = 0.86, SD 0.22), the inclusion of a proper radiological characterization in the list of characteristics would guarantee quality and safety in their use in comparison with products lacking this information. Some natural stones have been demonized for the potential exhalation of natural radioactivity, and the different parameters used should be addressed in a more systematic way.

  17. Research into basic rocks types

    International Nuclear Information System (INIS)

    1993-06-01

    Teollisuuden Voima Oy (TVO) has carried out research into basic rock types in Finland. The research programme has been implemented in parallel with the preliminary site investigations for radioactive waste disposal in 1991-1993. The program contained two main objectives: firstly, to study the properties of the basic rock types and compare those with the other rock types under the investigation; secondly, to carry out an inventory of rock formations consisting of basic rock types and suitable in question for final disposal. A study of environmental factors important to know regarding the final disposal was made of formations identified. In total 159 formations exceeding the size of 4 km 2 were identified in the inventory. Of these formations 97 were intrusive igneous rock types and 62 originally extrusive volcanic rock types. Deposits consisting of ore minerals, industrial minerals or building stones related to these formations were studied. Environmental factors like natural resources, protected areas or potential for restrictions in land use were also studied

  18. Reuse of residual sludge from stone-processing: differences and similarities between sludge coming from carbonate and silicate stones

    Science.gov (United States)

    Careddu, Nicola; Antonella Dino, Giovanna

    2015-04-01

    Residual sludge coming from dimension stone working activities represents a serious environmental and economic problem both for Stone Industry and citizens. Indeed, most of time, residual sludge is landfilled because of the difficulties to recover it; such difficulties are mainly connected to local legislation and a lack of proper protocols. In general, it is possible to individuate two different categories of sludge: residual sludge coming from carbonate rocks (CS) and those coming from silicate rocks (SS). Both of them are characterised by a very fine size distribution. CS is composed mainly by the same compounds of the processed stones (marble, limestone, travertine). The reason of this is related to the very slow wear of diamond tools during processing which entails a negligible content of heavy metals. CS becomes very interesting, from an economic point of view, when it has a CaCO3 grade > 95 %. On the contrary, SS is characterised by high heavy metal and TPH content. Residual sludge from the processing of silicate rocks can be split in three different sub-categories, depending on the way they are produced, and in particular: sludge from gangsaw using abrasive steel shot (GSS), sludge from multi diamond-saw block cutter (DBC), and mixed sludge (MS) from gangsaw and block cutter. These three sub-categories show different problems connected to heavy metal content, indeed on the one hand GSS is characterised by a high percentage of Ni, Cr, Cu, etc., on the other hand DBC is characterised by Co and Cu high content. In general, sludge, management of which in Italy is administered in accordance with the Italian Legislative Decree 152/06, can be used as waste from for environmental restoration or for cement plants. Several researches investigate the possible reuse of these materials but, at present time, there is no evidence of its systematic recovery as "recycled product" or "by-product". On the basis of the results of these researches it is possible to highlight

  19. Lioz: The Stone that made Lisbon reborn - A Global Heritage Stone Resource Proposal

    Science.gov (United States)

    Lopes, Luis

    2017-04-01

    Lioz: The Stone that made Lisbon reborn - A Global Heritage Stone Resource Proposal Explored since the Roman Period, the Lioz (Cenomanian age microcrystalline fossiliferous limestone) is the main stone used in the buildings and monuments of Lisbon. After the great cataclysm of 1755 (earthquake, tsunami and fire) of 1755, the already known great quality and the near occurrence of these limestones were wisely used in the great reconstruction of the "Capital do Império" (Capital of the Empire). At the time, Lisbon was one of the largest European cities and great business center of the World, so the necessary and urgent reconstruction was not so difficult to start. Sebastião José de Carvalho e Melo, better known as "Marquês de Pombal", Secretary of King José I, successfully took up the challenge of rebuilding Lisbon. Inside the actual Portuguese capital geographical limits, several quarries of the Cretaceous limestone were explored; some still exist and are classified as geomonuments (i.e., Rio Seco Geomonument, 38 ° 42'21 .67''N; 9 ° 11 '30.37''W). As the City boundaries expanded, the quarries stopped and now there is no one asset in Lisbon. The most important exploitation and processing Lioz stone center was situated in Pêro Pinheiro, 20 km NW of Lisbon. Most of the stones used in the National Palace-Convent of Mafra (1717) belongs to the four main types of Lioz (the cream/white "Abancado", the pink/dark pink "Encarnadão", the yellow "Amarelo de Negrais" and the blueish grey "Azulino"), either cut "against" (perpendicular to the bedding plane) or "along" (parallel to the bedding plane). The orientation stone cut deeply controls texture and mechanical properties of the rocks that behaves as different ones were considered. In the last two decades, the Lioz extraction was almost extinguished. However, some of the old quarries was reactivated and produces first quality blocks needed both for new works and restoration of historic buildings and monuments. The

  20. Hyperpolarized Xenon Nuclear Magnetic Resonance (NMR of Building Stone Materials

    Directory of Open Access Journals (Sweden)

    Michele Mauri

    2012-09-01

    Full Text Available We have investigated several building stone materials, including minerals and rocks, using continuous flow hyperpolarized xenon (CF-HP NMR spectroscopy to probe the surface composition and porosity. Chemical shift and line width values are consistent with petrographic information. Rare upfield shifts were measured and attributed to the presence of transition metal cations on the surface. The evolution of freshly cleaved rocks exposed to the atmosphere was also characterized. The CF-HP 129Xe NMR technique is non-destructive and it could complement currently used techniques, like porosimetry and microscopy, providing additional information on the chemical nature of the rock surface and its evolution.

  1. Do stone size and impaction influence therapeutic approach to proximal ureteral stones?

    Directory of Open Access Journals (Sweden)

    Radulović Slobodan

    2009-01-01

    Full Text Available Background/Aim. Primary therapeutic approach to lumbar ureteral stones is still contraversial. The aim of the study was to investigate the influence of stone impaction and size on the effectiveness of proximal ureteral stone lithotripsy. Methods. A total of 123 patients with proximal ureteral stones were investigated in this prospective study performed in a 10- month period. The patients were divided into the group I - 86 patients treated with extracorporeal shock wave lithotripsy (ESWL and the group II - 37 patients treated with 'Swiss' Lithoclast. In the group I, 49 stones (57% were classified as impacted, while 20 stones (23.3% were larger than 100 mm2. In the group II, 26 stones (70.3% were impacted, and 11 stones (29.7% were larger than 100 mm2. Stones were defined as impacted by the radiographic, echosonographic as well as endoscopic findings in the group II of patients. Stone size was presented in mm2. Chemical composition of stones were almost the same in both groups of the patients. Results. Generally, there was no statistically significant difference in the treatment success between the groups. However, stones larger than 100 mm2 were statistically more successfully treated endoscopically, while there was no statistical difference in the treatment success of impacted stones between these two groups. Conclusion. ESWL can by considered as primary first therapeutic approach in treatment of all proximal ureteral stones except for stones larger than 100 mm2 that should primarily be treated endoscopically.

  2. Geological and geomechanical properties of the carbonate rocks at the eastern Black Sea Region (NE Turkey)

    Science.gov (United States)

    Ersoy, Hakan; Yalçinalp, Bülent; Arslan, Mehmet; Babacan, Ali Erden; Çetiner, Gözde

    2016-11-01

    Turkey located in the Alpine-Himalayan Mountain Belt has 35% of the natural stone reserves of the world and has good quality marble, limestone, travertine and onyx reserves especially in the western regions of the country. The eastern Black Sea Region with a 1.4 million meters cubes reserve has a little role on the natural stone production in the country. For this reason, this paper deals with investigation on the potential of carbonate stone in the region and determination of the geological and geo-mechanical properties of these rocks in order to provide economic contribution to the national economy. While the study sites are selected among the all carbonate rock sites, the importance as well as the representative of the sites were carefully considered for the region. After representative samples were analyzed for major oxide and trace element compositions to find out petrochemical variations, the experimental program conducted on rock samples for determination of both physical and strength properties of the carbonate rocks. The results of the tests showed that there are significant variations in the geo-mechanical properties of the studied rock groups. The density values vary from 2.48 to 2.70 gr/cm3, water absorption by weight values range from 0.07 to 1.15% and the apparent porosity of the carbonate rocks are between 0.19 and 3.29%. However, the values of the UCS shows variation from 36 to 80 MPa. Tensile and bending strength values range from 3.2 to 7.5 MPa and 6.0-9.2 MPa respectively. Although the onyx samples have the lowest values of apparent porosity and water absorption by weight, these samples do not have the highest values of UCS values owing to occurrence of the micro-cracks. The UCS values of the rock samples were also found after cycling tests However, the limestone samples have less than 5% deterioration after freezing-thawing and wetting-drying tests, but travertine and onyx samples have more than 15% deterioration. Exception of the apparent

  3. Effect of shape and surface texture of aggregates during high intensity vertical shaft impact autogeneous crushing

    International Nuclear Information System (INIS)

    Samayamutthirian Palaniandy; Khairun Azizi Mohd Azizli

    2002-01-01

    The demand for quarry industry to produce high quality aggregates is increasing parallel with the demand of high strength concrete. Focus on the high quality aggregates production is very essential as 70% of the concrete consist of aggregates. High quality aggregate is characterised according to its shape, surface texture and its size distribution. The cubical and more equidimensional aggregates are characterised as high quality aggregates. Besides photomicrograph of aggregates, Flakiness and Elongation indices are important empirical measurements to determine the quality of the aggregates. The Barmac Rock On Rock Vertical Shaft Impactor proved that the shape of the aggregates can be improved by various crushing mechanisms as the EI and FI values were low and 75% of the cubical particles were observed in the crushed aggregates. (Author)

  4. Microalgae on dimension stone of a medieval castle in Thuringia

    Science.gov (United States)

    Hallmann, C.; Stannek, L.; Fritzlar, D.; Hoppert, M.

    2012-04-01

    Phototrophic microorganisms are important primary producers on hard rock substrata as well as on building facades. These eukaryotic microalgae and cyanobacteria, along with lichens, have also been recognized as important factors for rock weathering and stone decay. The rock substratum itself mostly provides extreme environmental conditions. Composition and diversity of sub-aeric phototrophic microbial communities is up to now poorly understood. Here we present a comparative study addressing the composition of algal biofilms on sandstone substrata based on the analysis of rDNA clone libraries from environmental samples and enrichment cultures. From a W-exposed, shaded wall area of a medieval castle ruin (Burg Gleichen, Thuringia, Germany cf. Hallmann et al., 2011), green algae like Prasiococcus, Prasiola and Elliptochloris could be retrieved. A ESE, sun-exposed wall section was colonized mainly by Apatococcus, Phyllosiphon and the lichen alga Trebouxia and Myrmecia. Accordingly, cyanobacterial communities show clear differences between both wall areas: the sun exposed area was dominated by Synechococcus-like organisms while on the W-exposed area cyanobacteria were almost absent. Just a few species, in particular Stichococcus-related strains, are ubiquitous in both areas. It is obvious that, apart from few generalists, different species colonize the wall areas that are situated in close vicinity, but provide different microclimatic conditions. These differences are discussed in view of biogenic weathering phenomena: certain microalgal species colonize crusts and scales along fracture planes and may contribute to rapid detachment and turnover of dimension stone surfaces. Hallmann, C., Fritzlar, D., Stannek, L., Hoppert, M. (2011) Ascomycete fungi on dimension stone of the "Burg Gleichen", Thuringia. Env. Earth Sci. 63, 1713-1722.

  5. Effect of pore structure on chemico-osmotic, diffusion and hydraulic properties of mud-stones

    International Nuclear Information System (INIS)

    Takeda, M.; Manaka, M.; Ito, K.; Miyoshi, S.; Tokunaga, T.

    2012-01-01

    Document available in extended abstract form only. An in-situ experiment by Neuzil (2000) has obtained the substantial proof of chemical osmosis in natural clayey formation. Chemical osmosis in clayey formations has thus received attention in recent years in the context of geological disposal of radioactive waste. Chemical osmosis is the diffusion of water through a semi-permeable membrane driven by the difference of chemical potentials between solutions to compensate the difference of water potentials, increasing the other potential differences, such as the pressure difference. Accordingly, the chemical osmosis could generate localized, abnormal fluid pressures in geological formations where formation media act as semi-permeable membranes and groundwater salinity is not uniform. Without taking account of the chemical osmosis, groundwater flow modeling may mislead the prediction of the groundwater flow direction. Therefore the possibility of chemical osmosis needs to be identified for potential host formations for radioactive waste repositories. The chemico-osmotic property of formation media is an essential parameter to identify the possibility of chemical osmosis in the formation; however, the diffusion and hydraulic properties are also fundamental parameters to estimate the duration of chemical osmosis since they control the spatial variation of salinity and the dissipation of osmotically induced pressures. In order to obtain the chemico-osmotic, diffusion and hydraulic parameters from a rock sample, this study developed a laboratory experimental system capable of performing chemical osmosis and permeability experiments. A series of experiments were performed on mud-stones. The chemico-osmotic parameter of each rock sample was further interpreted by the osmotic efficiency model proposed by Bresler (1973) to examine the pore structure inherent in rocks. Diatomaceous and siliceous mud-stone samples were obtained from drill cores taken from the Koetoi and Wakkanai

  6. Hyaluronan and Stone Disease

    Science.gov (United States)

    Asselman, Marino

    2008-09-01

    Kidney stones cannot be formed as long as crystals are passed in the urine. However, when crystals are retained it becomes possible for them to aggregate and form a stone. Crystals are expected to be formed not earlier than the distal tubules and collecting ducts. Studies both in vitro and in vivo demonstrate that calcium oxalate monohydrate crystals do not adhere to intact distal epithelium, but only when the epithelium is proliferating or regenerating, so that it possesses dedifferentiated cells expressing hyaluronan, osteopontin (OPN) and their mutual receptor CD44 at the apical cell membrane. The polysaccharide hyaluronan is an excellent crystal binding molecule because of its negative ionic charge. We hypothesized that the risk for crystal retention in the human kidney would be increased when tubular cells express hyaluronan at their apical cell membrane. Two different patient categories in which nephrocalcinosis frequently occurs were studied to test this hypothesis (preterm neonates and kidney transplant patients). Hyaluronan (and OPN) expression at the luminal membrane of tubular cells indeed was observed, which preceded subsequent retention of crystals in the distal tubules. Tubular nephrocalcinosis has been reported to be associated with decline of renal function and thus further studies to extend our knowledge of the mechanisms of retention and accumulation of crystals in the kidney are warranted. Ultimately, this may allow the design of new strategies for the prevention and treatment of both nephrocalcinosis and nephrolithiasis in patients.

  7. Measurement of natural radioactivity in commercial granites and glazing stones from Aswan area, Egypt

    International Nuclear Information System (INIS)

    Ahmad, F.; Shousha, H.A.

    2005-01-01

    Ornamental stones are considered as an important source of the mineral wealth in Egypt. These rocks have characteristics that enable them to be used in decoration as being hard, able to be polished and have low water absorption. A knowledge of radioactivity present in these natural rock samples helps to assess the possible radiological hazards to human health and hence take safety precautions if necessary. For the first time, the natural radioactivity of glazing stones used in granite possessing was measured. The concentration of natural radionuclides U-238, Th-232 and K-40 for eighteen ore and three processed granite samples from Aswan area have been determined using a shielded high purity germanium detector coupled to a computerized multichannel analyzer. Also, the gamma activities of 13 glazing stones, which are used in processing of granite, were measured. The average values of the measured activities for granite were 66.15 ± 4.48, 86.12 ± 5.43 and 1902.03 ± 50.64 Bq/kg and for glazing stones were 44.05 ± 3.54, 51.58 ± 4.44 and 87.55 ± 5.46 Bq/kg for U-238, Th-232 and K-40, respectively. The main absorbed dose rates were 167.04 ± 7.52 and 56.72 ± 7.00 n Gy/h at one meter above the ground level for granite and glazing stones, respectively. The average estimated radium equivalent was 335.75 ± 16.48 and 124.55 ± 11.36 Bq/kg for granite and glazing stones, respectively. This value is comparable with the reported values for many countries (370 Bq/kg). The external hazard index varied from 0.5 ± 0.02 to 1.79 ± 0.09 mGy/y for granite and from 0.042 ± 0.011 to 0.852 ± 0.080 mGy/y for glazing stones. Cs-137 concentration ranged from 0.15 ± 0.07 to 3.31 ± 0.29 Bq/kg for granite and from 0.29 ± 0.02 to 1.49 ± 0.010 Bq/kg for glazing stones. For glazing stones, the measured samples are acceptable for use and safe to the workers in granite processing. The radon exhalation rate for granite samples was calculated using nuclear track detector (CR-39). It was

  8. Calcium oxalate stone and gout.

    Science.gov (United States)

    Marickar, Y M Fazil

    2009-12-01

    Gout is well known to be produced by increased uric acid level in blood. The objective of this paper is to assess the relationship between gout and calcium oxalate stone formation in the humans. 48 patients with combination of gout and calcium oxalate stone problem were included. The biochemical values of this group were compared with 38 randomly selected uric acid stone patients with gout, 43 stone patients with gout alone, 100 calcium oxalate stone patients without gout and 30 controls, making a total of 259 patients. Various biochemical parameters, namely serum calcium, phosphorus and uric acid and 24-h urine calcium, phosphorus, uric acid, oxalate, citrate and magnesium were analysed. ANOVA and Duncan's multiple-range tests were performed to assess statistical significance of the variations. The promoters of stone formation, namely serum calcium (P stone patients and gouty calcium oxalate stone patients compared to the non-gouty patients and controls. Urine oxalate (P stones patients. The inhibitor urine citrate (P stone gouty patients, followed by the gouty uric acid stone formers and gouty calcium oxalate stone patients. The high values of promoters, namely uric acid and calcium in the gouty stone patients indicate the tendency for urinary stone formation in the gouty stone patients. There is probably a correlation between gout and calcium oxalate urinary stone. We presume this mechanism is achieved through the uric acid metabolism. The findings point to the summation effect of metabolic changes in development of stone disease.

  9. Utilization of unbound aggregates for road construction

    OpenAIRE

    Fladvad, Marit

    2017-01-01

    Crushed rock aggregate is a non-renewable resource of great interest in road construction and other branches of the construction industry. To prevent resource scarcity, utilization of aggregates should be considered carefully. © 2016 Norsk Bergforening

  10. Discussion on management of earth and rock balancing during the construction of Fuqing nuclear power plant

    International Nuclear Information System (INIS)

    Yan Yingdi; Gu Jian

    2013-01-01

    The main purpose of earth and stone work for Fuqing nuclear power plant is to solve problems of the main plant and the temporary accommodation site and also providing aggregate, marine stone and backfill as well. For a reasonable arrangement of stacking, using and spoiling, a dynamic balance management is performed in the project based on the initial design by the plant design institute. The design result would be used to conduct the construction arrangement, for avoiding the risk of earth and stone shortage, and enhancing the economic benefits. By discussing on problems existed in the balanced management of earth and stone, some suggestions are raised in this paper for optimizing earth and stone medium-and long-term management. (authors)

  11. Sustainable normal and high strength recycled aggregate concretes using crushed tested cylinders as coarse aggregates

    Directory of Open Access Journals (Sweden)

    Bilal S. Hamad

    2017-12-01

    Full Text Available The paper reports on a research program that was designed at the American University of Beirut (AUB to investigate the fresh and hardened mechanical properties of a high performance concrete mix produced with partial or full substitution of crushed natural lime-stone aggregates with recycled aggregates from crushed tested cylinders in batching plants. Choosing crushed cylinders as source of recycling would result in reusing portion of the waste products of the concrete production industry. An extensive concrete batching and testing program was conducted to achieve two optimum normal and high strength concrete mixes. The variables were the nominal concrete strength (28 or 60 MPa and the percentage replacement of natural coarse aggregates with recycled aggregates from crushed tested cylinders (0, 20, 40, 60, 80, or 100%. Normal strength tested cylinders were used as source of the recycled aggregates for the normal strength concrete (NSC mix and high strength tested cylinders were used for the high strength concrete (HSC mix. Tests on the trial batches included plastic state slump and hardened state mechanical properties including cylinder compressive strength, cylinder splitting tensile strength, modulus of elasticity, and standard beams flexural strength. The results indicated no significant effect on the slump and around 10% average reduction in the hardened mechanical properties for both investigated levels of concrete compressive strength.

  12. The brush model - a new approach to numerical modeling of matrix diffusion in fractured clay stone

    International Nuclear Information System (INIS)

    Lege, T.; Shao, H.

    1998-01-01

    A special approach for numerical modeling of contaminant transport in fractured clay stone is presented. The rock matrix and the fractures are simulated with individual formulations for FE grids and transport, coupled into a single model. The capacity of the rock matrix to take up contaminants is taken into consideration with a discrete simulation of matrix diffusion. Thus, the natural process of retardation due to matrix diffusion can be better simulated than by a standard introduction of an empirical parameter into the transport equation. Transport in groundwater in fractured clay stone can be simulated using a model called a 'brush model'. The 'brush handle' is discretized by 2-D finite elements. Advective-dispersive transport in groundwater in the fractures is assumed. The contaminant diffuses into 1D finite elements perpendicular to the fractures, i.e., the 'bristles of the brush'. The conclusion is drawn that matrix diffusion is an important property of fractured clay stone for contaminant retardation. (author)

  13. Erratics and Re-cycled Stone: scholarly irrelevancies or fundamental utilities to lithic studies in prehistoric Britain and beyond?

    Directory of Open Access Journals (Sweden)

    C. Stephen Briggs

    2009-09-01

    Full Text Available There are many theories explaining later prehistoric 'trade' and 'exchange systems' in stone artefacts. Evidence matching the petrographic information of transported implements with the country rock (local bedrock where 'factories' produced flaked stone axes is felt to be compelling. Consequently, across Europe it is widely believed that the only way 'factory' rock could have reached the places where artefacts have been found was by human carriage. The discovery of implement working floors, or 'factories' in montane areas (c. 1900-1970 on primary exposures of stone, lithologically almost identical to polished axes found considerable distances from them, has led to a belief in the industrial, economic or social processing and carriage of finished products. There are caveats to this proof of evidence, however. Natural processes constantly redistribute incalculable numbers of durable erratic pebble- to boulder-sized clasts, so why could these not have been used for making prehistoric artefacts? There is abundant evidence in the archaeological record that artefacts were crafted from such material. And although there is now an archive of petrographic thin-sections available to help to identify the origins of the artefacts, no comparable data are available on re-cycled stone. Implement provenancing is therefore unlikely to be of lasting scientific value until investigative programmes have accumulated far more accurate petrographic data on pebbles and erratics from superficial deposits. Comparisons between some British-Irish implement distribution patterns with those of glacial erratics suggests the available evidence already better fits an interpretation of deterministic and opportunistic stone procurement rather than one involving long-distance travel by prehistoric peoples. Extensive, long-term sampling and provenancing programmes are now needed to address this requirement.

  14. The Initial Appearance of Ashlar Stone in Cyprus. éssues of Provenance and Use

    Science.gov (United States)

    Philokyprou, M.

    In Cyprus stone was the primary building material, either as rubble or in a dressed form (called ashlar), since the Neolithic period. Initially stone was used only as rubble but later during the Late Brone Age ashlar stone appeared for the first time on the island. The aim of this paper is the presentation of the results of a systematic research regarding the different types and uses of ashlar stone and the techniques followed during the Late Bronze Age in Cyprus in comparison with other Mediterranean areas. The macroscopic and microscopic examination of selected samples showed that sedimentary rocks of various geological formations were used as ashlars. One, two or even three different types of stones were transported from the quarries nearest to the settlements. Some characteristic methods of stone dressing, such as finishing only the visible faces and creating drafted margins around the face of the ashlar blocks, are to be found not only in Late Bronze Age settlements but also in more recent examples from the last two centuries. The choice of ashlar and the methods of construction can be related to social, religious and political factors and were not only based on aesthetic criteria and practical issues. Thus, the most impressive structural solutions were followed in the construction of temples and public buildings, whereas more simple methods can be observed in residential complexes.

  15. Effect of stylolites on the durability of building stones : Two case studies

    NARCIS (Netherlands)

    Larbi, J.A.

    2003-01-01

    The mechanical properties and the durability of natural building stones are influenced to a large extent by inherent inhomogeneities. One of such inhomogeneities is a stylolite, particularly when it occuts in carbonate-rich rocks. Stylolites are irregular surfaces in which small tooth-like

  16. The fragmented character of Middle Palaeolithic stone tool technology.

    Science.gov (United States)

    Turq, Alain; Roebroeks, Wil; Bourguignon, Laurence; Faivre, Jean-Philippe

    2013-11-01

    The importance of the transport of stone artefacts in structuring Neandertal lithic assemblages has often been addressed, but the degree to which this led to fragmentation of lithic reduction over Middle Palaeolithic landscapes has not been explicitly studied thus far. Large-scale excavations of Middle Palaeolithic open-air sites and refitting studies of the retrieved assemblages have yielded new, high-resolution data on the mobile aspects of Neandertal stone tool technology. In this paper, we integrate lithic technology and raw material data from recent studies of Middle Palaeolithic open-air and rock shelter sites in Western Europe. We demonstrate that the results of a variety of typological, technological (especially refitting), and lithological studies have important consequences for our knowledge of the acquisition of raw materials and subsequent production, usage and discard of stone artefacts in the Middle Palaeolithic. Neandertal production and use of stone tools was fragmented in three domains: the spatial, the temporal and the social domain. We show that this versatile segmentation of stone artefact handling strategies is a main determinant of the character of the Neandertal archaeological record. Our data testify to ubiquitous and continuous transport of stone artefacts of a wide variety of forms, picked by Neandertals using selection criteria that were sometimes far removed from what archaeologists have traditionally considered, and to some degree still consider, to be desired end products of knapping activities. The data presented here testify to the variability and versatility of Middle Palaeolithic stone tool technology, whose fragmented character created very heterogeneous archaeological assemblages, usually the product of a wide variety of independent import, use, discard and/or subsequent transport events. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Stone composition and metabolic status.

    Science.gov (United States)

    Bibilash, B S; Vijay, Adarsh; Fazil Marickar, Y M

    2010-06-01

    This paper aims to study the correlation between biochemical risk factors of the stone former and the type of oxalate stone formed, namely calcium oxalate monohydrate (COM) and calcium oxalate dehydrate (COD). A retrospective study of 487 patients who had been attending the urinary stone clinic, Trivandrum during 1998-2007 was conducted. The stones retrieved from them were subjected to chemical analysis and FTIR spectrographic analysis. They were categorized into COM, COD, mixed COM+COD and others. Of 142 pure calcium oxalate stone patients, 87 were predominantly COM stone formers and 55 COD stone formers. Their metabolic status of 24 h urine and serum was assessed. The values of urine calcium, phosphorus, uric acid, magnesium, creatinine, oxalate, citric acid, sodium and potassium, serum values of calcium, phosphorus, uric acid, magnesium and creatinine and calculated values of creatinine clearance, tubular reabsorption of phosphate, calcium magnesium ratio and calcium oxalate ratio were recorded. Comparison was made between the COM stone group and the COD stone group. Patients forming COM stones had significantly higher mean values for urine calcium (P stone forming patients. All other values failed to show significant difference. Patients, with higher urine oxalate, formed COM stones. Those with low magnesium (which is an inhibitor) formed more of COD stones. Urine calcium was high in both groups without showing significant variation from the mean. In patients with high calcium-oxalate and calcium-magnesium ratios, there is higher chance of forming a COD stone than COM. Identification of the crystallization pattern of the calcium stone will help in selecting treatment modalities.

  18. Investigation and hazard assessment of the 2003 and 2007 Staircase Falls rock falls, Yosemite National Park, California, USA

    Directory of Open Access Journals (Sweden)

    G. F. Wieczorek

    2008-05-01

    Full Text Available Since 1857 more than 600 rock falls, rock slides, debris slides, and debris flows have been documented in Yosemite National Park, with rock falls in Yosemite Valley representing the majority of the events. On 26 December 2003, a rock fall originating from west of Glacier Point sent approximately 200 m3 of rock debris down a series of joint-controlled ledges to the floor of Yosemite Valley. The debris impacted talus near the base of Staircase Falls, producing fragments of flying rock that struck occupied cabins in Curry Village. Several years later on 9 June 2007, and again on 26 July 2007, smaller rock falls originated from the same source area. The 26 December 2003 event coincided with a severe winter storm and was likely triggered by precipitation and/or frost wedging, but the 9 June and 26 July 2007 events lack recognizable triggering mechanisms. We investigated the geologic and hydrologic factors contributing to the Staircase Falls rock falls, including bedrock lithology, weathering, joint spacing and orientations, and hydrologic processes affecting slope stability. We improved upon previous geomorphic assessment of rock-fall hazards, based on a shadow angle approach, by using STONE, a three-dimensional rock-fall simulation computer program. STONE produced simulated rock-fall runout patterns similar to the mapped extent of the 2003 and 2007 events, allowing us to simulate potential future rock falls from the Staircase Falls detachment area. Observations of recent rock falls, mapping of rock debris, and simulations of rock fall runouts beneath the Staircase Falls detachment area suggest that rock-fall hazard zones extend farther downslope than the extent previously defined by mapped surface talus deposits.

  19. Investigation and hazard assessment of the 2003 and 2007 Staircase Falls rock falls, Yosemite National Park, California, USA

    Science.gov (United States)

    Wieczorek, G. F.; Stock, G. M.; Reichenbach, P.; Snyder, J. B.; Borchers, J. W.; Godt, J. W.

    2008-05-01

    Since 1857 more than 600 rock falls, rock slides, debris slides, and debris flows have been documented in Yosemite National Park, with rock falls in Yosemite Valley representing the majority of the events. On 26 December 2003, a rock fall originating from west of Glacier Point sent approximately 200 m3 of rock debris down a series of joint-controlled ledges to the floor of Yosemite Valley. The debris impacted talus near the base of Staircase Falls, producing fragments of flying rock that struck occupied cabins in Curry Village. Several years later on 9 June 2007, and again on 26 July 2007, smaller rock falls originated from the same source area. The 26 December 2003 event coincided with a severe winter storm and was likely triggered by precipitation and/or frost wedging, but the 9 June and 26 July 2007 events lack recognizable triggering mechanisms. We investigated the geologic and hydrologic factors contributing to the Staircase Falls rock falls, including bedrock lithology, weathering, joint spacing and orientations, and hydrologic processes affecting slope stability. We improved upon previous geomorphic assessment of rock-fall hazards, based on a shadow angle approach, by using STONE, a three-dimensional rock-fall simulation computer program. STONE produced simulated rock-fall runout patterns similar to the mapped extent of the 2003 and 2007 events, allowing us to simulate potential future rock falls from the Staircase Falls detachment area. Observations of recent rock falls, mapping of rock debris, and simulations of rock fall runouts beneath the Staircase Falls detachment area suggest that rock-fall hazard zones extend farther downslope than the extent previously defined by mapped surface talus deposits.

  20. Evaluation of stone durability using a combination of ultrasound, mechanical and accelerated aging tests

    International Nuclear Information System (INIS)

    Molina, E; Cultrone, G; Sebastián, E; Alonso, F J

    2013-01-01

    The durability of a rock when exposed to decay agents is an important criterion when assessing its quality as a building material. Our study focuses on six varieties of natural stone (two limestones, one dolostone, one travertine and two sandstones) that are widely used in both new and historical buildings. In order to assess their quality, we measured and characterized their dynamic elastic properties using ultrasounds, we measured their compressive strength using the uniaxial compression test and we evaluated their durability by means of accelerated aging tests (freeze-thaw and salt crystallization). In order to get a full picture of the decay suffered by the different stones, we determined the composition and amount of the clay fraction of the six stones. We also observed small fragments subjected to the salt crystallization test under an environmental scanning electron microscope to study any textural change and measured the changes of colour on the surface with a spectrophotometer. Finally, we analysed the pore system of the stones before and after their deterioration using mercury injection porosimetry. We then compared the results for the different stones and found that dolostone obtained the best results, while the two limestones proved to be the least durable and had the lowest compressive strength. (paper)

  1. The "green stones" of Valtellina and Valchiavenna (central Alps, northern Italy)

    Science.gov (United States)

    Cavallo, Alessandro

    2015-04-01

    Valtellina and Val Chiavenna (Sondrio, Central Alps, northern Italy) are traditionally areas of production of building and ornamental stones (e.g. Serizzo Ghiandone, Serizzo Valmasino, San Fedelino Granite), and among these the "green stones" have a leading position. These stones had an extensive use in Lombardy, as well as abroad (e.g Switzerland). The "green stones" are related to the two mafic-ultramafic bodies of Valmalenco and Chiavenna, where the two largest quarrying districts of the Province of Sondrio are located. Until the early decades of the XX century, serpentinites (and other lithologies from Valtellina) were also extracted from the erratic boulders of Brianza (north of Milan), but at present time the law protects the few remaining boulders. The extracted and processed materials are various: serpentinites, ophicalcites, soapstones. Even the "Stone of Tresivio", used in the past in important monuments of Valtellina, could be classified among the "green stones" in a broad sense: it is a green chloritic schist with scarce and thin ferriferous calcitic veins, pertaining to the sedimentary "Servino" Formation. In recent times, the ancient quarries of this stone were rediscovered near the homonymous village, a few kilometers from Sondrio. There are also historic reports about other "green stones", used in ancient times, such as the "Stone of Grosio", a chloritic schist, and the "Bormio Prasinite". Currently the extraction and processing of "green stones" occurs mostly in Valmalenco, with 22 active serpentinite quarries and a gross volume of 70000 m3 extracted per year, with a yield of about 50%. The Malenco serpentinite (interpreted as sub-continental mantle rocks) forms a 1-2 km thick tabular body, outcropping over an area of about 170 km2, almost entirely confined within the boundaries of the valley. The antigoritic serpentinites (with variable amounts of olivine, clinopyroxene, chlorite and magnetite) are moderately up to strongly foliated, sometimes

  2. Experimental study of thermo-hydro-mechanical behaviour of Callovo-Oxfordian Clay-stone

    International Nuclear Information System (INIS)

    Mohajerani, M.

    2011-01-01

    During the different phases of the exothermic radioactive waste deep disposal (excavation, operation) and after permanent closure, the host rock is submitted to various coupled mechanical, hydraulic and thermal phenomena. Hence, a thorough investigation of the thermo-hydro-mechanical behaviour of the rock is necessary to complete existing data and to better understand and model the short and long term behaviour of the Callovo-Oxfordian (COx) clay formation in Bure (Meuse/Haute-Marne - M/HM), considered by ANDRA as a potential host rock in France.In this work, the compression - swelling behaviour of the COx Clay-stone was first investigated by carrying out a series of high-pressure oedometric tests. The results, interpreted in terms of coupling between damage and swelling, showed that the magnitude of swelling was linked to the density of the fissures created during compression. In a second step, the hydro-mechanical and thermo-hydro-mechanical behaviour of the saturated Clay-stone under a mean stress close to the in situ one were investigated by using two devices with short drainage path (10 mm), namely a isotropic cell and a newly designed hollow cylinder triaxial cell with local displacement measurements. These devices helped to solve two majors problems related to testing very low permeability materials: i) a satisfactory previous sample saturation (indicated by good Skempton values) and ii) satisfactory drainage conditions. Some typical constitutive parameters (Skempton and Biot's coefficients, drained and undrained compressibility coefficients) have been determined at ambient temperature through isotropic compression tests that also confirmed the transverse isotropy of the Clay-stone. The consistency of the obtained parameters has been checked in a saturated poro-elastic framework. Two aspects of the thermo-hydro-mechanical behaviour of the COx Clay-stone have then been investigated through different heating tests and through drained and undrained isotropic

  3. Effect of the pre-treatment and the aggregate content on the adhesion strength of repair mortars on Miocene porous limestone

    Science.gov (United States)

    Szemerey-Kiss, Balázs; Török, Ákos

    2016-04-01

    The adhesion between porous limestone and newly prepared repair mortars are crucial in the preservation of historic stone structures. Besides mechanical compatibility other matches such as chemical composition and porosity are also essential, but the current research focuses on the adhesion strength of repair mortars that are used in the restoration of Hungarian porous limestone. 8 mortars (4 commercial and 4 specially prepared) were selected for the tests. Mortars with different amount of aggregate were prepared and caste to stone surface. The stone substrate was highly porous Miocene limestone. The strength was tested by standardized pull-out tests which method is commonly used for concrete testing. The limestone surfaces were either used in their natural conditions or were pre-treated (pre-wetting). The strength of the stone/mortar bond was tested. The failure mechanism was documented and various failure modes were identified. Strength test results suggest that especially pre-treatment influences strongly the pull-out strength at mortar/stone interface. Increasing aggregate content also reduces pull out strength of tested repair mortars, but at various rates depending on the mortar type. The financial support of OTKA post-doctoral grant to BSZK (reference number is: PD 112-955) and National Research, Development and Innovation (NKFI) Fund to ÁT (ref. no. K 116532) are appreciated.

  4. Antagonistic perception of a rock-mass as geomorphosite and/or mineral resource with specific concern of natural stone for heritage conservation

    Science.gov (United States)

    Prikryl, Richard

    2016-04-01

    Prior to industrial era, the quarrying of natural stone was primarily local (the stone has been used very close to its extraction in most of the cases), small scale, occasional (the stone has been extracted only when needed for specific construction, permanent operations were much rarer than nowadays) but long-term (the quarrying activity at one site persisted over centuries very often). The landscape affected by such quarrying (as we can observe it at present) gained numerous new values (e.g., increased morphological contrast, succession of wildlife habitat, etc.) that are often appreciated more than the presence of valuable mineral resource - natural stone. If these site were claimed natural monuments or gained another type of environmental protection, any further extraction of natural stone is prohibited. However, if the specific site was used for extraction of natural stone that has been used for construction which later became cultural heritage object, the antagonistic perception of the site might appear - the site might be protected as a geomorphosite but, at the same time, it can be a source of unique natural stone required for the restoration of cultural heritage objects. This paper, along with above mentioned basic relationships, provides some real examples connected with the difficulties to find the extractable source of natural stone for restoration of iconic cultural heritage objects - specifically search for sources of Carboniferous arkoses to be used for replacement of the decayed ashlars at the Gothic Charles Bridge in Prague (Czech Republic).

  5. Veneration and Spiritual Pleading through Stone: observations and musings on current practice in rural Turkmenistan

    Directory of Open Access Journals (Sweden)

    Glenys McLaren

    2009-09-01

    Full Text Available Although the population of Turkmenistan is essentially Moslem, older traditions co-exist. In the rural areas medical services are poor, infant mortality and maternal mortality and morbidity are higher than in the West, and superstition is rife. Barrenness is considered a female failing. Women of child-bearing age are under great pressure to be fertile, and make spiritual pleas at venerated sites when pregnancy fails to occur or an infant is lost. There is veneration not only of shrines and revered burial sites but also of ancient sites and old dead trees. Many offerings are in the form of stone or fossils, with continued reuse and deposition of ancient materials. Cloth strips and miniature cradles bearing 'babies' are left in association with stones in pleas for child-bearing. Some stones are handled in special ways. One large stone was used for masturbation in the hope of fecundity. The legend of Paraw Bibi incorporates many of the beliefs and features related to rock that occur across many cultures and are common to folklore of old. Resonances of the same thought processes and behaviour patterns could have originated in the ancient past.

  6. Penggunaan Limbah Batu Marmer Dari Gunung Batu Naitapan Kabupaten Timor Tengah Selatan

    OpenAIRE

    Nauk, Sepriulus S; Hunggurami, Elia; Bolla, Margareth E

    2012-01-01

    The activity of marble mining at Mount Naitapan produces wastes such as powder and marble rocks. Efforts to utilize this waste as an alternative to aggregate in concrete mix. This research aims to discover the magnitude of compressive strength if aggregates in concrete that using marble waste as replacement. Specimens used is concrete cylinders. The marble waste used in three treatments of substitution they were substitution of marble powder by sand, marble rocks by the split stone, marbl...

  7. Evaluation of Colemanite Waste as Aggregate Hot Mix Asphalt Concrete

    Directory of Open Access Journals (Sweden)

    Nihat MOROVA

    2015-09-01

    Full Text Available In this study usability of waste colemanite which is obtained after cutting block colemanite for giving proper shape to blocks as an aggregate in hot mix asphalt. For this aim asphalt concrete samples were prepared with four different aggregate groups and optimum bitumen content was determined. First of all only limestone was used as an aggregate. After that, only colemanite aggregate was used with same aggregate gradation. Then, the next step of the study, Marshall samples were produced by changing coarse and fine aggregate gradation as limestone and colemanite and Marshall test were conducted. When evaluated the results samples which produced with only limestone aggregate gave the maximum Marshall Stability value. When handled other mixture groups (Only colemanite, colemanite as coarse aggregate-limestone as fine aggregate, colemanite as fine aggregate-limestone as coarse aggregate all groups were verified specification limits. As a result, especially in areas where there is widespread colemanite waste, if transportation costs did not exceed the cost of limestone, colemanite stone waste could be used instead of limestone in asphalt concrete mixtures as fine aggregate

  8. Microbiological influences on fracture surfaces of intact mud-stone

    International Nuclear Information System (INIS)

    West, J.M.; Harrison, H.; Wragg, J.; Wagner, D.; Milodowski, A.E.; Turner, G.; Lacinska, A.; Holyoake, S.; Harrington, J.; Coombs, P.; Bateman, K.; Yoshikawa, H.; Sasaki, Y.; Aoki, K.

    2012-01-01

    Document available in extended abstract form only. It is well recognised that microbes live in a wide range of subsurface environments including potential geological repository host rocks; and their presence can have an impact on transport processes. Microbial activity in any environment is located on chemical or physical interfaces, usually within bio-films. Their impact on transport can be physical (e.g. altering porosity) and/or chemical (e.g. changing redox conditions or altering pH) often resulting in intracellular or extracellular mineral formation or degradation. Consequently, the significance of microbial activity on the transport properties of potential host rocks for geological repositories is now being investigated. This pilot study investigates changes in transport properties that are because of microbial activity in sedimentary mud-stone rock environments at the Japan Atomic Energy Agency (JAEA) Horonobe underground research laboratory (URL) in northern Japan. The geological setting of the URL is summarised elsewhere. Geo-microbiological assessments of ground waters, from boreholes, previously drilled at Horonobe, have revealed the presence of a diverse indigenous microbiological ecosystem. The impacts of the presence of these microbes on the performance of a high-level radioactive waste (HLW) repository, using geo-microbiological data from Horonobe, has shown that denitrifying bacteria is likely to be the group of organisms with the greatest activity. Consequently, the impact of this group of organisms, specifically Pseudomonas denitrificans, on Horonobe rock transport properties, is the focus of this study. In brief, two experiments, one biotic and a 'control', were carried out using a flow-through column operated at a constant rate of fluid flow and under pressurised conditions. Changes in biological and chemical parameters were monitored throughout the experiment together with changes in confining pressure and temperature. The experiments were

  9. Occurrence and Sources of Aliphatic Hydrocarbons in Soils within ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Keywords: Asphalt Plants; Soil; Aliphatic hydrocarbons; Pristane; Phytane. Hot mix asphalt (HMA) plant is an assemblage of mechanical equipment where aggregates or inert mineral materials such as sand, gravel, crushed stones, Slag, rock dust or powder are blended, heated, dried and mixed with bitumen in measured ...

  10. Metabolic Characteristics and Risks Associated with Stone Recurrence in Korean Young Adult Stone Patients.

    Science.gov (United States)

    Kang, Ho Won; Seo, Sung Pil; Kim, Won Tae; Kim, Yong-June; Yun, Seok-Joong; Kim, Wun-Jae; Lee, Sang-Cheol

    2017-08-01

    The aim of this study was to assess the metabolic characteristics and risks of stone recurrence in young adult stone patients in Korea. The medical records of 1532 patients presenting with renal or ureteric stones at our stone clinic between 1994 and 2015 were retrospectively reviewed. Patients were grouped according to age (young adult, 18-29 years; intermediate onset, 30-59 years; old age, ≥60 years) at first presentation, and measurements of clinicometabolic characteristics and risks of stone recurrence were compared. Overall, excretion of urinary stone-forming substances was highest in the intermediate onset group, followed by the young adult and old age groups. Importantly, excretion of urinary citrate was lowest in the young adult group. Kaplan-Meier analyses identified a significant difference between the three age groups in terms of stone recurrence (log rank test, p adult stone patients. Younger age (18-29 years) at first stone presentation was a significant risk factor for stone recurrence, and urinary citrate excretion was an independent risk factor affecting recurrence in this group. Metabolic evaluation and potassium citrate therapy should be considered for young adult stone patients to prevent recurrence.

  11. Percutaneous suprapubic stone extraction for posterior urethral stones in children: efficacy and safety.

    Science.gov (United States)

    Safwat, Ahmed S; Hameed, Diaa A; Elgammal, Mohamed A; Abdelsalam, Yasser M; Abolyosr, Ahmad

    2013-08-01

    To evaluate the safety and efficacy of percutaneous suprapubic stone extraction (PSPSE) for pediatric posterior urethral stones. Between July 2007 and June 2010, 54 boys presenting with acute urinary retention due to posterior urethral stones underwent PSPSE. Patients were a mean age of 66.4 months (range, 8-180 months). The stone size was 0.7-1.9 cm. Patients were placed under general anesthesia, and a 7F urethroscope was used to pushback the stone to the bladder. A 3-mm suprapubic puncture with a scalpel was performed, followed by insertion of a straight narrow hemostat through the puncture aided with cystoscopic guidance. The stone was grasped with the hemostat in its narrowest diameter and was extracted percutaneously or crushed if friable. The suprapubic puncture was closed with a single 4-0 Vicryl (Ethicon) suture. Intact stone retrieval was achieved in 45 patients, and the stone was crushed into minute fragments in 9 patients. Intraperitoneal extravasation developed in 1 patient that required open surgical intervention. Mean operative time was 22 minutes. Patients were monitored for up to 17 months, with complete resolution of symptoms and stone clearance. PSPSE provides a minimally invasive approach for the extraction of urethral and bladder stones in the pediatric population. The use of a straight hemostat for suprapubic stone extraction or crushing is a good alternative to suprapubic tract dilation, with minimal morbidity. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. IGCP 637 Heritage Stone Designation: A UNESCO and IUGS project on natural stones

    Science.gov (United States)

    Pereira, Dolores; Cooper, Barry; Schouenborg, Björn; Marker, Brian; Kramar, Sabina

    2017-04-01

    IGCP 637 was approved in 2015 to facilitate establishment of a new international geological standard for building and ornamental stones. Formal international recognition of those natural stone types that have achieved widespread utilization in human culture is now underway and the term "Global Heritage Stone Resource" (GHSR) has been proposed for this designation. Stones that have been used in heritage construction, sculptural masterpieces, as well as in utilitarian (yet culturally important) applications are obvious GHSR candidates. In co-ordination with these aims the project has an associated role to promote the adoption and use of the GHSR designation. Consequently an interim list of potential GHSRs is maintained and a register of GHSR approved stones is being created. IGCP 637 also enhances the capacity of the International Union of Geological Sciences (IUGS) in the realm of dimension stone and geological standards as it is the first IUGS involvement in this subject. As a consequence, the largest known international grouping of dimension stone professionals has been established. Within IGCP 637 a web page has been created at www.globalheritagestone.com, including information on the Working Group and also specific information on the evolution of the project. Several researchers were funded to attend the Heritage Stone working group activities, including researchers from Algeria, Malawi, India, Italy and Russia. We also have produced many publications, both as individual papers and special issues in journals included in the Journal Citation Reports. Monographs are being prepared at present. Hopefully, IGCP 637 will help to widen the circle of researchers interested in natural stones as part of our geoheritage. Heritage Stone references: articles and special issues - Pereira, D. and Marker, B. (2016) The value of original natural stone in the context of architectural heritage. Geosciences, 6, 13. - Heritage Stone 1. Ed. Pereira and Pratt. (2016). Geoscience

  13. Influence of classical and rock music on red blood cell rheological properties in rats.

    Science.gov (United States)

    Erken, Gulten; Bor Kucukatay, Melek; Erken, Haydar Ali; Kursunluoglu, Raziye; Genc, Osman

    2008-01-01

    A number of studies have reported physiological effects of music. Different types of music have been found to induce different alterations. Although some physiological and psychological parameters have been demonstrated to be influenced by music, the effect of music on hemorheological parameters such as red blood cell (RBC) deformability and aggregation are unknown. This study aimed at investigating the effects of classical and rock music on hemorheological parameters in rats. Twenty-eight rats were divided into four groups: the control, noise-applied, and the classical music- and rock music-applied groups. Taped classical or rock music were played repeatedly for 1 hour a day for 2 weeks and 95-dB machine sound was applied to the noise-applied rats during the same period. RBC deformability and aggregation were measured using an ektacytometer. RBC deformability was found to be increased in the classical music group. Exposure to both classical and rock music resulted in a decrement in erythrocyte aggregation, but the decline in RBC aggregation was of a higher degree of significance in the classical music group. Exposure to noise did not have any effect on the parameters studied. The results of this study indicate that the alterations in hemorheological parameters were more pronounced in the classical music group compared with the rock music group.

  14. Shock Wave Lithotripsy in Ureteral Stones: Evaluation of Patient and Stone Related Predictive Factors

    Directory of Open Access Journals (Sweden)

    Ozgur Yazici

    2015-08-01

    Full Text Available ABSTRACTPurpose:To evaluate the patient and stone related factors which may influence the final outcome of SWL in the management of ureteral stones.Materials and Methods:Between October 2011 and October 2013, a total of 204 adult patients undergoing SWL for single ureteral stone sizing 5 to 15 mm were included into the study program. The impact of both patient (age, sex, BMI, and stone related factors (laterality, location, longest diameter and density as CT HU along with BUN and lastly SSD (skin to stone distance on fragmentation were analysed by univariate and multivariate analyses. Results: Stone free rates for proximal and distal ureteral stones were 68.8% and 72.7%, respectively with no statistically significant difference between two groups (p=0.7. According to univariate and multivariate analyses, while higher BMI (mean: 26.8 and 28.1, p=0.048 and stone density values (mean: 702 HU and 930 HU, p<0.0001 were detected as statistically significant independent predictors of treatment failure for proximal ureteral stones, the only statistically significant predicting parameter for the success rates of SWL in distal ureteral stones was the higher SSD value (median: 114 and 90, p=0.012.Conclusions:Our findings have clearly shown that while higher BMI and increased stone attenuation values detected by NCCT were significant factors influencing the final outcome of SWL treatment in proximal ureteral stones; opposite to the literature, high SSD was the only independent predictor of success for the SWL treatment of distal ureteral stones.

  15. The Effect of Morphological Characteristic of Coarse Aggregates Measured with Fractal Dimension on Asphalt Mixture’s High-Temperature Performance

    Directory of Open Access Journals (Sweden)

    Hainian Wang

    2016-01-01

    Full Text Available The morphological properties of coarse aggregates, such as shape, angularity, and surface texture, have a great influence on the mechanical performance of asphalt mixtures. This study aims to investigate the effect of coarse aggregate morphological properties on the high-temperature performance of asphalt mixtures. A modified Los Angeles (LA abrasion test was employed to produce aggregates with various morphological properties by applying abrasion cycles of 0, 200, 400, 600, 800, 1000, and 1200 on crushed angular aggregates. Based on a laboratory-developed Morphology Analysis System for Coarse Aggregates (MASCA, the morphological properties of the coarse aggregate particles were quantified using the index of fractal dimension. The high-temperature performances of the dense-graded asphalt mixture (AC-16, gap-graded stone asphalt mixture (SAC-16, and stone mastic asphalt (SMA-16 mixtures containing aggregates with different fractal dimensions were evaluated through the dynamic stability (DS test and the penetration shear test in laboratory. Good linear correlations between the fractal dimension and high-temperature indexes were obtained for all three types of mixtures. Moreover, the results also indicated that higher coarse aggregate angularity leads to stronger high-temperature shear resistance of asphalt mixtures.

  16. Influence of carbonate micro-fabrics on the failure strength of Callovo-Oxfordian clay stones and Opalinus Clay

    International Nuclear Information System (INIS)

    Klinkenberg, M.; Dohrmann, R.; Kaufhold, S.; Siegesmund, S.

    2010-01-01

    Document available in extended abstract form only. The potential use of clay stones as host rock for radioactive waste disposal is currently investigated. For this application, hydraulic conductivity, swelling properties, water uptake, rheological and mechanical properties are of great importance. The Opalinus Clay (Mont-Terri, Switzerland) and the Callovo- Oxfordian clay stone (France) are the most frequently studied clay stones. One goal is to develop a numerical model being able to predict the mechanical behaviour of clay stones under repository-like conditions. Experimental investigations reveal that Opalinus Clay and Callovo-Oxfordian clay stone behave different with respect to the dependence of mechanical strength on the carbonate content. The failure strength of Opalinus Clay decreases with increasing carbonate content, whereas it increases with increasing carbonate content when Callovo-Oxfordian clay stone is considered. To supply proper data and enable reliable model assumptions, the use of suitable experimental techniques for the description of the microstructure is indispensable. After mechanical testing, samples were taken perpendicular to the bedding and polished sections were prepared. The micro-fabrics were investigated using scanning electron microscopy (SEM) and image analysis. Backscattered electron (BSE) images were used for the image analysis because carbonates can be extracted by grey level analysis. The image analysis of the extracted particles provides the following parameters: area, longest and shortest axis of an ellipse (surrounding the particle), perimeter, the angle to horizontal (longest axis), and the aspect ratio (longest axis/shortest axis). Callovo-Oxfordian clay stone shows a homogenous distribution of fine-grained carbonates and dovetail connection of calcium carbonate with the clayey matrix. In contrast Opalinus Clay shows large elongated carbonate grains (high aspect ratios) of shell fragments. Cracks are mostly related to these

  17. Detailed Aggregate Resources Study, Dry Lake Valley, Nevada.

    Science.gov (United States)

    1981-05-29

    LOCAL SAND SOURCES IGENERALLY CYLINDERS. DRYING SHRINKAGE I COLLECTED WITHIN A FEW MILES OF CORRESPONDING LEDGE-ROCK SOURCES) SUPPLIED FINE MENS...COMPRESSIVE AND TENSILE STh LEDGE-ROCK SOURCES SUPPLIED COARSE AGGREGATES; LOCAL SAND SOURCES IGENERALLY CYLINDERS. DRYING SHRINKAGE COLLECTED WITHIN A FEW

  18. Effect of aggregate graining compositions on skid resistance of Exposed Aggregate Concrete pavement

    Science.gov (United States)

    Wasilewska, Marta; Gardziejczyk, Wladysław; Gierasimiuk, Pawel

    2018-05-01

    The paper presents the evaluation of skid resistance of EAC (Exposed Aggregate Concrete) pavements which differ in aggregate graining compositions. The tests were carried out on concrete mixes with a maximum aggregate size of 8 mm. Three types of coarse aggregates were selected depending on their resistance to polishing which was determined on the basis of the PSV (Polished Stone Value). Basalt (PSV 48), gabbro (PSV 50) and trachybasalt (PSV 52) aggregates were chosen. For each type of aggregate three graining compositions were designed, which differed in the content of coarse aggregate > 4mm. Their content for each series was as follows: A - 38%, B - 50% and C - 68%. Evaluation of the skid resistance has been performed using the FAP (Friction After Polishing) test equipment also known as the Wehner/Schulze machine. Laboratory method enables to compare the skid resistance of different types of wearing course under specified conditions simulating polishing processes. In addition, macrotexture measurements were made on the surface of each specimen using the Elatexure laser profile. Analysis of variance showed that at significance level α = 0.05, aggregate graining compositions as well as the PSV have a significant influence on the obtained values of the friction coefficient μm of the tested EAC pavements. The highest values of the μm have been obtained for EAC with the lowest amount of coarse aggregates (compositions A). In these cases the resistance to polishing of the aggregate does not significantly affect the friction coefficients. This is related to the large areas of cement mortar between the exposed coarse grains. Based on the analysis of microscope images, it was observed that the coarse aggregates were not sufficiently exposed. It has been proved that PSV significantly affected the coefficient of friction in the case of compositions B and C. This is caused by large areas of exposed coarse aggregate. The best parameters were achieved for the EAC pavements

  19. Infection (urease) stones.

    Science.gov (United States)

    Griffith, D P; Osborne, C A

    1987-01-01

    Infection-induced stones in man probably form solely as a consequence of urealysis which is catalyzed by the bacterial protein urease. Urease stones composed of struvite and carbonate-apatite may form primarily, or as secondary stones or pre-existent metabolic stones. Struvite stones form and grow rapidly owing to (a) supersaturation of urine with stone forming salts, (b) 'salting out' of poorly soluble organic substances normally dissolved in urine and (c) ammonia-induced destruction of the normally protective urothelial glycosaminoglycan layer. Immature (predominantly organic) matrix stones mature into densely mineralized stones. Curative treatment is possible only by eliminating all of the stone and by eradicating all urinary and parenchymal infection. A variety of operative and pharmaceutical approaches are available. Patient treatment must be individualized inasmuch as some patients are better candidates for one type of treatment than another.

  20. Why Was Silcrete Heat-Treated in the Middle Stone Age? An Early Transformative Technology in the Context of Raw Material Use at Mertenhof Rock Shelter, South Africa.

    Directory of Open Access Journals (Sweden)

    Patrick Schmidt

    Full Text Available People heat treated silcrete during the Middle Stone Age (MSA in southern Africa but the spatial and temporal variability of this practice remains poorly documented. This paucity of data in turn makes it difficult to interrogate the motive factors underlying the application of this technique. In this paper we present data on heat treatment of silcrete through the Howiesons Poort and post-Howiesons Poort of the rock shelter site Mertenhof, located in the Western Cape of South Africa. In contrast to other sites where heat treatment has been documented, distance to rock source at Mertenhof can be reasonably well estimated, and the site is known to contain high proportions of a diversity of fine grained rocks including silcrete, hornfels and chert at various points through the sequence. Our results suggest the prevalence of heat treatment is variable through the sequence but that it is largely unaffected by the relative abundance of silcrete prevalence. Instead there is a strong inverse correlation between frequency of heat treatment in silcrete and prevalence of chert in the assemblage, and a generally positive correlation with the proportion of locally available rock. While it is difficult to separate individual factors we suggest that, at Mertenhof at least, heat treatment may have been used to improve the fracture properties of silcrete at times when other finer grained rocks were less readily available. As such, heat treatment appears to have been a component of the MSA behavioural repertoire that was flexibly deployed in ways sensitive to other elements of technological organisation.

  1. SHAPE ANALYSIS OF FINE AGGREGATES USED FOR CONCRETE

    OpenAIRE

    HE, Huan; Courard, Luc; Pirard, Eric; Michel, Frédéric

    2016-01-01

    Fine aggregate is one of the essential components in concrete and significantly influences the material properties. As parts of natures, physical characteristics of fine aggregate are highly relevant to its behaviors in concrete. The most of previous studies are mainly focused on the physical properties of coarse aggregate due to the equipment limitations. In this paper, two typical fine aggregates, i.e. river sand and crushed rock, are selected for shape characterization. The new developed d...

  2. Optically stimulated luminescence dating of rock surfaces

    DEFF Research Database (Denmark)

    Sohbati, Reza

    There are many examples of rock surfaces, rock art and stone structures whose ages are of great importance to the understanding of various phenomena in geology, climatology and archaeology. Optically stimulated luminescence (OSL) dating is a well-established chronological tool that has successfully...... to include the effects of the environmental dose rate. By fitting the model to the dose-depth variation from a single clast, four events (two light exposures of different durations each followed by a burial period) in the history of a single cobble are identified and quantified. However, the use of model...

  3. Assessment of stone composition in the management of urinary stones

    NARCIS (Netherlands)

    Kijvikai, Kittinut; de la Rosette, J. J. M.

    2011-01-01

    Several explanations have been suggested to account for the failure of extracorporeal shockwave lithotripsy (ESWL) treatment in patients with urinary stones, including large stone volume, unfavorable stone location or composition and the type of lithotriptor used. Unfavorable stone composition is

  4. Factors affecting stone-free rate and complications of percutaneous nephrolithotomy for treatment of staghorn stone.

    Science.gov (United States)

    el-Nahas, Ahmed R; Eraky, Ibrahim; Shokeir, Ahmed A; Shoma, Ahmed M; el-Assmy, Ahmed M; el-Tabey, Nasr A; Soliman, Shady; Elshal, Ahmed M; el-Kappany, Hamdy A; el-Kenawy, Mahmoud R

    2012-06-01

    To determine factors affecting the stone-free rate and complications of percutaneous nephrolithotomy (PNL) for treatment of staghorn stones. The computerized database of patients who underwent PNL for treatment of staghorn stones between January 2003 and January 2011 was reviewed. All perioperative complications were recorded and classified according to modified Clavien classification system. The stone-free rate was evaluated with low-dose noncontrast computed tomography (CT). Univariate and multivariate statistical analyses were performed to determine factors affecting stone-free and complication rates. The study included 241 patients (125 male and 116 female) with a mean age of 48.7 ±14.3 years. All patients underwent 251 PNL (10 patients had bilateral stones). The stone-free rate of PNL monotherapy was 56% (142 procedures). At 3 months, the stone-free rate increased to 73% (183 kidneys) after shock wave lithotripsy. Independent risk factors for residual stones were complete staghorn stone and presence of secondary calyceal stones (relative risks were 2.2 and 3.1, respectively). The complication rate was 27% (68 PNL). Independent risk factors for development of complications were performance of the procedure by urologists other than experienced endourologist and positive preoperative urine culture (relative risks were 2.2 and 2.1, respectively). Factors affecting the incidence of residual stones after PNL are complete staghorn stones and the presence of secondary calyceal stones. Complications are significantly high if PNL is not performed by an experienced endourologist or if preoperative urine culture is positive. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Steatite and schist as contenders for the Global Heritage Stone Resource due to their importance in Brazil's natural stone built heritage

    Science.gov (United States)

    Gilberto Costa, Antônio

    2013-04-01

    In Brazil, European natural stones, such as marble and limestone, were used as building material at historically important buildings and monuments, mainly in coastal cities, as well as in contemporary urban centers. However, in the country's central region, these Italian and Portuguese marbles and limestones were scarcely used. Instead, they were substituted for soapstone and several types of schist. As of 1755, the former was employed because of the ease with which it can be worked, essentially in the sculptural art and in the production of ornamental elements. Characterized by the presence of talc, steatite can feature other minerals such as serpentine, chlorite, carbonate, amphiboles, oxides like hematite and magnetite, and sulfites like pyrite, all in broadly variable amounts, which can result in modification of its technological properties (Volumetric Weight, Porosity, Water Absorption, Uniaxial Compression, Abrasion Resistance, Thermal Expansion etc.). In such rocks, talc content will be a decisive factor in their coloration. The higher its talc content is the clearer and softer the stone type will be, which ends up being known as talc stone. In such cases, the rock can display different hues of green, blue and gray. When compared to other rocks, texture patterns containing talc crystals, chlorite and carbonate contribute to low absorption and porosity for steatites. Schists were equally used at historical buildings in the Brazilian inland, especially in constructions in Minas Gerais towns, both in the production of structural elements such as bases, corners, pillars and foundations and in the creation of ornaments. Featuring different compositions, such rocks - which almost always occur interlayered with other ones such as quartzite - display coloration ranging from hues of gray to green to blue. They can be quartz-sericite-albite-chlorite schists featuring great or no amounts of carbonate, magnetite, epidote and tourmaline, sometimes with garnet, such as in

  6. A case report of ureteral cast stone and giant urethral stone, respectively

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Yung; Rhee, Song Joo; Choi, Ki Chul [School of Medicine, Jeongbug National University, Jeonju (Korea, Republic of)

    1980-12-15

    Urinary lithiasis is one of the most common disease of the urinary tract. It occurs more frequently in men than in women but rare in children and in blacks; a familial predisposition is often encountered. Ureteral stones originate in the kidney. Gravity and peristalis contribute to spontaneous passage into and down the ureter. Ureterovesical junction is the most frequent lodging site of stone. In our hospital one case of ureteral cast stone and giant urethral stone were found respectively and they were confirmed by radiological examination and surgery on Aug. 1978 and Jan. 1979. Ureteral cast stone which had been introduced and named first by Kiyonobu Tari and Kikjiro So in 1972 was very giant unusually. It may be the only one till now. Our patient was 36 years old female who has been suffered from intermittent right flank pain for 10 years. On KUB giant cylindrical radiopaque shadow was shown on RLQ extended to right minor pelvis and this was confirmed as a stone by retrograde ureteral catheterization. A stone measured 13cm x 1.5cm was found above the ureterovesical junction during operation. Follow up excretory urogram one year after operation showed no functional improvement of right kidney. Urethral stone is also unusual urinary lithiasis. This 60 years old male patient was been suffered from non-tender palpable hard mass on scrotal area and intermittent urinary retention. When urinary retention was occurred it was relieved by manipulation of the mass by himself. On plain film oval shaped giant radiopaque shadow was shown on cavernous urethral region. On urethrocystogram anterior urethra was opacified, but posterior urethra and bladder were not opacified and multiple fistulous leakage was identified. A stone measured 6.5cm x 3.5cm was found in cavernous urethra during operation.

  7. A case report of ureteral cast stone and giant urethral stone, respectively

    International Nuclear Information System (INIS)

    Song, Ho Yung; Rhee, Song Joo; Choi, Ki Chul

    1980-01-01

    Urinary lithiasis is one of the most common disease of the urinary tract. It occurs more frequently in men than in women but rare in children and in blacks; a familial predisposition is often encountered. Ureteral stones originate in the kidney. Gravity and peristalis contribute to spontaneous passage into and down the ureter. Ureterovesical junction is the most frequent lodging site of stone. In our hospital one case of ureteral cast stone and giant urethral stone were found respectively and they were confirmed by radiological examination and surgery on Aug. 1978 and Jan. 1979. Ureteral cast stone which had been introduced and named first by Kiyonobu Tari and Kikjiro So in 1972 was very giant unusually. It may be the only one till now. Our patient was 36 years old female who has been suffered from intermittent right flank pain for 10 years. On KUB giant cylindrical radiopaque shadow was shown on RLQ extended to right minor pelvis and this was confirmed as a stone by retrograde ureteral catheterization. A stone measured 13cm x 1.5cm was found above the ureterovesical junction during operation. Follow up excretory urogram one year after operation showed no functional improvement of right kidney. Urethral stone is also unusual urinary lithiasis. This 60 years old male patient was been suffered from non-tender palpable hard mass on scrotal area and intermittent urinary retention. When urinary retention was occurred it was relieved by manipulation of the mass by himself. On plain film oval shaped giant radiopaque shadow was shown on cavernous urethral region. On urethrocystogram anterior urethra was opacified, but posterior urethra and bladder were not opacified and multiple fistulous leakage was identified. A stone measured 6.5cm x 3.5cm was found in cavernous urethra during operation

  8. Deterioration of the volcanic kerb and pavement stones in a humid environment in the city centre of Izmir, Turkey

    Science.gov (United States)

    Yavuz, A. B.

    2006-11-01

    İzmir is the third largest city in Turkey and has being the centre of art, culture, tourism and trade activities throughout the 5,000 years of its history. Natural stones brought from different parts of the world have been widely used for construction of the prestigious buildings, monuments and roads etc., in the past in the city. Renovation of the street pavements and public gathering areas in the city centre has been undertaken by the Metropolitan Municipality in 2000 and continued through the year of 2001. These renovation activities have mainly been carried out in the streets running parallel to the sea shore. Volcanic rocks brought from the Central Anatolia Ankara-Gölbaşı (andesites) and Kayseri-İncesu (tuffs) have been used in the renovation works. These rocks have shown extensive deteriorations within 4 years of their usage between 2001 and 2005 under the influence of different environmental factors. In this study, the deteriorations developed in the recently placed volcanic rocks used as kerb and pavement stones in the city centre of İzmir in the light of their mineralogical, chemical, physical and mechanical properties, used locations and the environmental factors are presented.

  9. Mobility of zinc in the Callovo-Oxfordian clay-stone

    Energy Technology Data Exchange (ETDEWEB)

    Savoye, S.; Fayette, A.; Beaucaire, C. [CEA, DEN, DPC, SECR, L3MR, F-91191 Gif s/Yvette (France); Lacour, J.-L. [CEA, DEN, DPC, SEARS, LANIE, F-91191 Gif s/Yvette (France)

    2013-07-01

    The diffusion of zinc was studied in the Callovo-Oxfordian clay-stone, which is a potential host rock for the retrievable disposal of high-level radioactive wastes. Two in-diffusion laboratory experiments were performed with initial zinc concentrations of 4 10{sup -5} mol L{sup -1} and 8 10{sup -6} mol L{sup -1} (resp.) for 35 days. The zinc rock profile was acquired using an original technique, the μLIBS, with a high resolution (10 μm), calibrated with the abrasive peeling method. The experimental data, i.e. Zn concentration monitoring in the source reservoir and Zn rock profile, were successfully reproduced using a chemical-transport code. In that code, the sorption of Zn was described by a multi-site ion-exchange model, with only the effective diffusion coefficient value being adjusted (De = 8 10{sup -11} m{sup 2} s{sup -1}). This De value, 2 times higher than that of tritiated water, indicates that zinc, like most cations, is also subject to enhanced diffusion in clay rocks. (authors)

  10. Kidney stone erosion by micro scale hydrodynamic cavitation and consequent kidney stone treatment.

    Science.gov (United States)

    Perk, Osman Yavuz; Şeşen, Muhsincan; Gozuacik, Devrim; Koşar, Ali

    2012-09-01

    The objective of this study is to reveal the potential of micro scale hydrodynamic bubbly cavitation for the use of kidney stone treatment. Hydrodynamically generated cavitating bubbles were targeted to the surfaces of 18 kidney stone samples made of calcium oxalate, and their destructive effects were exploited in order to remove kidney stones in in vitro experiments. Phosphate buffered saline (PBS) solution was used as the working fluid under bubbly cavitating conditions in a 0.75 cm long micro probe of 147 μm inner diameter at 9790 kPa pressure. The surface of calcium oxalate type kidney stones were exposed to bubbly cavitation at room temperature for 5 to 30 min. The eroded kidney stones were visually analyzed with a high speed CCD camera and using SEM (scanning electron microscopy) techniques. The experiments showed that at a cavitation number of 0.017, hydrodynamic bubbly cavitation device could successfully erode stones with an erosion rate of 0.31 mg/min. It was also observed that the targeted application of the erosion with micro scale hydrodynamic cavitation may even cause the fracture of the kidney stones within a short time of 30 min. The proposed treatment method has proven to be an efficient instrument for destroying kidney stones.

  11. Assessment of industrial minerals and rocks in the controlled area

    International Nuclear Information System (INIS)

    Castor, S.B.; Lock, D.E.

    1996-01-01

    Yucca Mountain in Nye County, Nevada, is a potential site for a permanent repository for high-level nuclear waste in Miocene ash flow tuff. The Yucca Mountain controlled area occupies approximately 98 km 2 that includes the potential repository site. The Yucca Mountain controlled area is located within the southwestern Nevada volcanic field, a large area of Miocene volcanism that includes at least four major calderas or cauldrons. It is sited on a remnant of a Neogene volcanic plateau that was centered around the Timber Mountain caldera complex. The Yucca Mountain region contains many occurrences of valuable or potentially valuable industrial minerals, including deposits with past or current production of construction aggregate, borate minerals, clay, building stone, fluorspar, silicate, and zeolites. The existence of these deposits in the region and the occurrence of certain mineral materials at Yucca Mountain, indicate that the controlled area may have potential for industrial mineral and rock deposits. Consideration of the industrial mineral potential within the Yucca Mountain controlled area is mainly based on petrographic and lithologic studies of samples from drill holes in Yucca Mountain. Clay minerals, zeolites, fluorite, and barite, as minerals that are produced economically in Nevada, have been identified in samples from drill holes in Yucca Mountain

  12. Assessment of industrial minerals and rocks in the controlled area

    Energy Technology Data Exchange (ETDEWEB)

    Castor, S.B. [Nevada Bureau of Mines and Geology, Reno, NV (United States); Lock, D.E. [Mackay School of Mines, Reno, NV (United States)

    1996-08-01

    Yucca Mountain in Nye County, Nevada, is a potential site for a permanent repository for high-level nuclear waste in Miocene ash flow tuff. The Yucca Mountain controlled area occupies approximately 98 km{sup 2} that includes the potential repository site. The Yucca Mountain controlled area is located within the southwestern Nevada volcanic field, a large area of Miocene volcanism that includes at least four major calderas or cauldrons. It is sited on a remnant of a Neogene volcanic plateau that was centered around the Timber Mountain caldera complex. The Yucca Mountain region contains many occurrences of valuable or potentially valuable industrial minerals, including deposits with past or current production of construction aggregate, borate minerals, clay, building stone, fluorspar, silicate, and zeolites. The existence of these deposits in the region and the occurrence of certain mineral materials at Yucca Mountain, indicate that the controlled area may have potential for industrial mineral and rock deposits. Consideration of the industrial mineral potential within the Yucca Mountain controlled area is mainly based on petrographic and lithologic studies of samples from drill holes in Yucca Mountain. Clay minerals, zeolites, fluorite, and barite, as minerals that are produced economically in Nevada, have been identified in samples from drill holes in Yucca Mountain.

  13. Compositions of stone and stone surface materials of historical monuments from Vidzeme and Zemgale

    International Nuclear Information System (INIS)

    Actins, A.; Spricis, A.; Zekunde, A.; Nemerova, A.

    2004-01-01

    By means of x-ray analysis composition of stone and stone surface materials of historical monuments from Vidzeme and Zemgale was investigated. Corrosion products of tuffa materials were identified on surfaces of some investigated monuments. Similarity of composition of products of stone corrosion for monuments from Latvia and Poland was recognised. Content of heavy metals at stone materials of historical monuments and at the surface layers of these monuments was investigated by means of atomic absorption and potentiometric stripping methods. Reasons of formation of compounds and pollution of investigated samples were discussed. (full text)

  14. Open stone surgery: a still-in-use approach for complex stone burden.

    Science.gov (United States)

    Çakici, Özer Ural; Ener, Kemal; Keske, Murat; Altinova, Serkan; Canda, Abdullah Erdem; Aldemir, Mustafa; Ardicoglu, Arslan

    2017-06-30

    Urinary stone disease is a major urological condition. Endourologic techniques have influenced the clinical approach and outcomes. Open surgery holds a historic importance in the management of most conditions. However, complex kidney stone burden may be amenable to successful results with open stone surgery. In this article, we report our eighteen cases of complex urinary stone disease who underwent open stone removal. A total of 1701 patients have undergone surgical treatment for urinary stone disease in our clinic between July 2012 and July 2016, comprising eighteen patients who underwent open stone surgery. Patients' demographic data, stone analysis results, postoperative clinical data, and stone status were evaluated retrospectively. The choice of surgical approach is mostly dependent on the surgeon's preference. In two patients, open surgery was undertaken because of perioperative complications. We did not observe any Clavien-Dindo grade 4 or 5 complications. Three patients were managed with a course of antibiotics due to postoperative fever. One patient had postoperative pleurisy, one patient had urinoma, and two patients had postoperative ileus. Mean operation time was 84 (57-124) minutes and mean hospitalization time was 5.5 (3-8) days. Stone-free status was achieved in 15 patients (83.3%). Endourologic approaches are the first options for treatment of urinary stone disease. However, open stone surgery holds its indispensable position in complicated cases and in complex stone burden. Open stone surgery is also a valid alternative to endourologic techniques in all situations.

  15. Evaluation of Accelerated Ageing Tests for Metallic and Non-Metallic Graffiti Paints Applied to Stone

    Directory of Open Access Journals (Sweden)

    Patricia Sanmartín

    2017-10-01

    Full Text Available Graffiti are increasingly observed on urban and peri-urban buildings and their removal requires a huge financial outlay by local governments and agencies. Graffiti are not usually removed immediately, but rather over the passage of time, viz. months or even years. In this study, which forms part of a wider research project on graffiti removal, different methods (gravimetric analysis, examination of digital images, colour and infrared measurements were used to evaluate the performance of accelerated ageing tests (involving exposure to humidity, freeze-thawing cycles and NaCl and Na2SO4 salts for graffiti painted on stone. Silver (metallic and black (non-metallic graffiti spray paints were applied to two types of igneous rock (granite and rhyolitic ignimbrite and one sedimentary rock (fossiliferous limestone, i.e., biocalcarenite. The metallic and non-metallic graffiti spray paints acted differently on the stone surfaces, both chemically and physically. Older graffiti were found to be more vulnerable to weathering agents. The ageing test with NaCl and particularly Na2SO4, both applied to granite, proved the most severe on the paints, yielding more detrimental and faster artificial ageing of the type of material under study.

  16. Studies on various characteristics of concrete structures using crushed sand

    International Nuclear Information System (INIS)

    Mimatsu, Makoto; Sugita, Hideaki; Yonemura, Masataka.

    1985-01-01

    With the recent advances of construction industry, the demands for concrete, hence for aggregate, are rising. The sand as such is in extreme shortage due to the exhaustion of river sand. Under the situation, the recent trends are for the use of crushed sand, i.e. the artificial sand obtained by crushing rocks, which have advantages of stabilized quality and adequate supplies. In building of nuclear power plants requiring large amounts of concrete, the usage of crushed sand is now unavoidable. The following are described : the situation of aggregate in Kyushu. production method of crushed sand and the quality standards, rocks used for crushed stone and sand and the properties, quality survey on crushed sand and the basic tests, characteristic tests of crushed-stone and -sand mixed concrete, the application of crushed sand in structures of the Sendai Nuclear Power Station. (Mori, K.)

  17. The relevance of "Santa Pudia" calcarenite: a natural stone to preserve heritage buildings in Andalusia (Spain)

    Science.gov (United States)

    Navarro, Rafael; Molina, Eduardo; Baltuille, José Manuel

    2013-04-01

    "Santa Pudia" calcarenite, extracted in quarries from Granada (Andalusia, Spain), is a very important ornamental stone used in some of the main historical buildings in Andalusia, and particularly in the city of Granada. It has been used mainly outdoors with structural purposes (ashlars, columns), but is also used as decorative element in façades, pinnacles, etc. There are two main quarries, one historical ("Las Parideras") and another one currently under exploitation ("La Escribana"). Both were the source for all the material to make the different cited elements. Some of the main historical buildings using this stone in their construction, in one way or other, are the cathedral, The Royal Chapel, the Royal Hospital, San Juan de Dios monastery, the Royal Chancery or Carlos V Palace in the Alhambra, all of them in the city of Granada. In recent days, this natural stone has been used in the restoration of the Mosque of Córdoba and the Cinco Llagas Hospital in Seville. Although the main reference in industry for this natural stone is "Calcarenita de Santa Pudia", it can be found as well cited in the old literature under the denomination of "Piedra Franca". From a geological point of view is a white to yellow calcarenite, part of the Tortonian deposits of the Guadalquivir Basin (Post-Orogenic Neogene Basins of the Betic Chains). It's made up mainly by micritic matrix of calcite, with fragments of bioclasts (about 90%) including molluscs, echinoderms, briozoan, red algae and foraminifera. Other components, like metamorphic quartz, moscovite and/or schist or gneiss (rock fragments from the nearby metamorphic basement), can be found as well. The rock is poorly cemented with sparitic calcite. Regarding the main physical and mechanical properties, this rock has an open porosity between 25-36%, bulk density of 1,74 g/cm3, water absorption values at atmospheric pressure of 16%, compressive strength (dry) of 11 MPa, flexural strength (dry) of 2,3 MPa and salt crystallization

  18. ETHNO ARCHAEOLOGY OF ROCK ART IN PENINSULAR INDIA

    Indian Academy of Sciences (India)

    user

    ETHNO ARCHAEOLOGY. OF. ROCK ART. IN. PENINSULAR INDIA. Presented by: D K K CHAKRAVARTY. Dr.K.K.CHAKRAVARTY. Page 2. UTTARAKHAND. Page 3. Lakhu-udyar, Almora. Page 4. Lakhu –udyar, Almora. Page 5. Sati Stone, Dwarson (Almora). Page 6. Chanchridhar, Almora. Page 7. Digoli, Almora. Page 8 ...

  19. A quick in-situ estimating method for grading stone products as radiation protection standard of building materials

    International Nuclear Information System (INIS)

    Nanping, Wang; Shengli, Hou; Yexun, Chen

    2002-01-01

    Natural stone is word-widely used as building and decorating material, which is made of marble, granite or other kinds of rocks. Normally they are cut into rectangle with 20 mm thickness. In order to grade small size stone plank as radioactive protection standard (China Standard GB6566-2001), a quick in-situ technique and a special kind of portable -ray detector is developed. The detector is made of NaI (Tl) ( 30x50mm) with a shield (Model ZDD3901, China Patent No. 992080045). The difference modeling was established for small-size stone planks grading. About 96.3% stone plank samples which size are more than 300x300x20 mm could be determined radiation levels by in-situ techniques, by which the grading results (A, B or C) are coincided with quantity analysis in lab

  20. A quick in-situ estimating method for grading stone products as radiation protection standard of building materials

    Energy Technology Data Exchange (ETDEWEB)

    Nanping, Wang; Shengli, Hou; Yexun, Chen [China Univ. of Geosciences, Bijing (China)

    2002-07-01

    Natural stone is word-widely used as building and decorating material, which is made of marble, granite or other kinds of rocks. Normally they are cut into rectangle with 20 mm thickness. In order to grade small size stone plank as radioactive protection standard (China Standard GB6566-2001), a quick in-situ technique and a special kind of portable -ray detector is developed. The detector is made of NaI (Tl) ( 30x50mm) with a shield (Model ZDD3901, China Patent No. 992080045). The difference modeling was established for small-size stone planks grading. About 96.3% stone plank samples which size are more than 300x300x20 mm could be determined radiation levels by in-situ techniques, by which the grading results (A, B or C) are coincided with quantity analysis in lab.

  1. Bath Stone - a Possible Global Heritage Stone from England

    Science.gov (United States)

    Marker, Brian

    2014-05-01

    The Middle Jurassic strata of England have several horizons of oolitic and bioclastic limestones that provide high quality dimension stone. One of the most important is found in and near the City of Bath. The Great Oolite Group (Upper Bathonian) contains the Combe Down and Bath Oolites, consisting of current bedded oolites and shelly oolites, that have been used extensively as freestones for construction nearby, for prestigious buildings through much of southern England and more widely. The stone has been used to some extent since Roman times when the city, then known as Aquae Sulis, was an important hot spa. The stone was used to a limited extent through medieval times but from the early 18th century onwards was exploited on a large scale through surface quarrying and underground mining. The City was extensively redeveloped in the 18th to early 19th century, mostly using Bath Stone, when the spas made it a fashionable resort. Buildings from that period include architectural "gems" such as the Royal Crescent and Pulteney Bridge, as well as the renovated Roman Baths. Many buildings were designed by some of the foremost British architects of the time. The consistent use of this stone gives the City an architectural integrity throughout. These features led to the designation of the City as a World Heritage Site. It is a requirement in current City planning policy documents that Bath Stone should be used for new building to preserve the appearance of the City. More widely the stone was used in major houses (e.g. Buckingham Palace and Apsley House in London; King's Pavilion in Brighton); civic buildings (e.g. Bristol Guildhall; Dartmouth Naval College in Devon); churches and cathedrals (e.g. Truro Cathedral in Cornwall); and engineered structures (e.g. the large Dundas Aqueduct on the Kennet and Avon Canal). More widely, Bath Stone has been used in Union Station in Washington DC; Toronto Bible College and the Town Hall at Cape Town, South Africa. Extraction declined in

  2. Contribution of stone size to chronic kidney disease in kidney stone formers.

    Science.gov (United States)

    Ahmadi, Farrokhlagha; Etemadi, Samira Motedayen; Lessan-Pezeshki, Mahbob; Mahdavi-Mazdeh, Mitra; Ayati, Mohsen; Mir, Alireza; Yazdi, Hadi Rokni

    2015-01-01

    To determine whether stone burden correlates with the degree of chronic kidney disease in kidney stone formers. A total of 97 extracorporeal shockwave lithotripsy candidates aged 18 years and older were included. Size, number and location of the kidney stones, along with cumulative stone size, defined as the sum of diameters of all stones) were determined. Estimated glomerular filtration rate was determined using the Chronic Kidney Disease Epidemiology Collaboration cystatin C/creatinine equation, and chronic kidney disease was defined as estimated glomerular filtration rate chronic kidney disease. The relationship persisted even after adjustment for age, sex, body mass index, C-reactive protein, fasting plasma glucose, thyroid stimulating hormone, presence of microalbuminuria, history of renal calculi, history of extracorporeal shockwave lithotripsy, number and location of the stones (odds ratio 1.24, 95% confidence interval 1.02-1.52). The same was not observed for individuals with a cumulative stone size ≥ 20 mm. In kidney stone formers with a cumulative stone size up to 20 mm, estimated glomerular filtration rate linearly declines with increasing cumulative stone size. Additionally, cumulative stone size is an independent predictor of chronic kidney disease in this group of patients. © 2014 The Japanese Urological Association.

  3. Durability testing of basic crystalline rocks and specification for use as road base aggregate

    CSIR Research Space (South Africa)

    Paige-Green, P

    2007-02-01

    Full Text Available , it was necessary to develop a preliminary performance ranking to assess the most appropriate material properties and test results. This was based on the observed disintegration of aggregate pieces soaked in ethylene 8 glycol combined with past testing of basic... biased towards the crushing test results as the Aggregate Crushing Value (ACV), 10% Fines Aggregate Crushing test (10%FACT) and Mod Aggregate Impact Value (AIV) are all included. In addition, six or seven different treatments are included...

  4. Fasting and Urinary Stones

    Directory of Open Access Journals (Sweden)

    Ali Shamsa

    2013-11-01

    Full Text Available Introduction: Fasting is considered as one of the most important practices of Islam, and according to Prophet Mohammad, fasting is obligatory upon Muslims. The aim of this study is to evaluate the effects of fasting on urinary stones. Materials and Methods: Very few studies have been carried out on urinary stones and the effect of Ramadan fasting. The sources of the present study are Medline and articles presented by local and Muslim researchers. Meanwhile, since we are acquainted with three well-known researchers in the field of urology, we contacted them via email and asked for their professional opinions. Results: The results of studies about the relationship of urinary stones and their incidence in Ramadan are not alike, and are even sometimes contradictory. Some believe that increased incidence of urinary stones in Ramadan is related not to fasting, but to the rise of weather temperature in hot months, and an increase in humidity. Conclusion: Numerous biological and behavioral changes occur in people who fast in Ramadan and some researchers believe that urinary stone increases during this month.

  5. Evaluation of Different Mineral Filler Aggregates for Asphalt Mixtures

    Science.gov (United States)

    Wasilewska, Marta; Małaszkiewicz, Dorota; Ignatiuk, Natalia

    2017-10-01

    Mineral filler aggregates play an important role in asphalt mixtures because they fill voids in paving mix and improve the cohesion of asphalt binder. Limestone powder containing over 90% of CaCO3 is the most frequently used type of filler. Waste material from the production of coarse aggregate can be successfully used as a mineral filler aggregate for hot asphalt concrete mixtures as the limestone powder replacement. This paper presents the experimental results of selected properties of filler aggregates which were obtained from rocks with different mineral composition and origin. Five types of rocks were used as a source of the mineral filler aggregate: granite, gabbro, trachybasalt, quartz sandstone and rocks from postglacial deposits. Limestone filler was used in this study as the reference material. The following tests were performed: grading (air jet sieving), quality of fines according to methylene blue test, water content by drying in a ventilated oven, particle density using pyknometer method, Delta ring and ball test, Bitumen Number, fineness determined as Blaine specific surface area. Mineral filler aggregates showed significant differences when they were mixed with bitumen and stiffening effect in Delta ring and ball test was evaluated. The highest values were achieved when gabbro and granite fillers were used. Additionally, Scanning Electron Microscopy (SEM) analysis of grain shape and size was carried out. Significant differences in grain size and shape were observed. The highest non-homogeneity in size was determined for quartz sandstone, gabbro and granite filler. Their Blaine specific surface area was lower than 2800 cm2/g, while for limestone and postglacial fillers with regular and round grains it exceeded 3000 cm2/g. All examined mineral filler aggregates met requirements of Polish National Specification WT-1: 2014 and could be used in asphalt mixtures.

  6. INVESTIGATION OF SKID RESISTANCE PROPERTIES OF AGGREGATES USED IN AFYONKARAHISAR CITY PAVEMENTS

    Directory of Open Access Journals (Sweden)

    Cahit GÜRER

    2007-02-01

    Full Text Available For a safe driving, pavement surface aggregates must have superior physical and mechanical properties. Although high rate of accidents is mainly due to drivers errors, pavement surface properties affect significantly occurance of traffic accidents. The most important factor in the highways leading to traffic accidents are the skid resistance. In this study, adherence test with Vialit plate, Nicholson stripping test, accelerated polishing test (PSV were carried out on four aggregate samples which were used in seal coats and hot mix asphalt in Afyonkarahisar City. Results were compared with values of specification limits. The results showed that particularly limestone aggregates polishing stone values are poorer than volcanic aggregates sample. Especially, use of aggregates having a good polishing resistance, will be an important factor increasing driving safety.

  7. Modelling of the mechanical behaviour and damage of clay-stones: application to the East argillite

    International Nuclear Information System (INIS)

    Aublive-Conil, N.

    2003-03-01

    The storage in deep geological formation is one of the solutions retained by France for the management of highly long life radioactive waste. The retained host rock is a clay-stone named East argillite located in the departments of Meuse and Haute-Marne. A thermodynamic formulation is used to propose a rheological model, which reproduces the mechanical behavior of clay-stones. Initially, an anisotropic damage plastic model was formulated in order to describe material degradations. Then, the damage plastic model is reformulated in order to taken into account the damage influence on the hydraulic behavior of porous material. The numerical simulations correctly reproduce the mechanical behavior of East Argillites but also the anisotropy of the hydraulic behavior introduced by the damage effect. (author)

  8. The bowing potential of granitic rocks: rock fabrics, thermal properties and residual strain

    Science.gov (United States)

    Siegesmund, S.; Mosch, S.; Scheffzük, Ch.; Nikolayev, D. I.

    2008-10-01

    The bowing of natural stone panels is especially known for marble slabs. The bowing of granite is mainly known from tombstones in subtropical humid climate. Field inspections in combination with laboratory investigations with respect to the thermal expansion and the bowing potential was performed on two different granitoids (Cezlak granodiorite and Flossenbürg granite) which differ in the composition and rock fabrics. In addition, to describe and explain the effect of bowing of granitoid facade panels, neutron time-of-flight diffraction was applied to determine residual macro- and microstrain. The measurements were combined with investigations of the crystallographic preferred orientation of quartz and biotite. Both samples show a significant bowing as a function of panel thickness and destination temperature. In comparison to marbles the effect of bowing is more pronounced in granitoids at temperatures of 120°C. The bowing as well as the thermal expansion of the Cezlak sample is also anisotropic with respect to the rock fabrics. A quantitative estimate was performed based on the observed textures. The effect of the locked-in stresses may also have a control on the bowing together with the thermal stresses related to the different volume expansion of the rock-forming minerals.

  9. Trapping or tethering stones (TS: A multifunctional device in the Pastoral Neolithic of the Sahara.

    Directory of Open Access Journals (Sweden)

    Marina Gallinaro

    Full Text Available The Pierres de Ben Barour, also known as trapping or tethering stones (TS, are stone artefacts with notches or grooves usually interpreted as hunting devices on the basis of rock art engravings. Though their presence is a peculiar feature of desert landscapes from the Sahara to the Arabian Peninsula, we know little about their age, context and function. Here we present a new approach to the study of these artefacts based on a large dataset (837 items recorded in the Messak plateau (SW Libya. A statistically-based geoarchaeological survey carried out between 2007 and 2011 in Libya, alongside landscape and intra-site analyses of specific archaeological features (such as rock art, settlement and ceremonial contexts, reveal that these artefacts were used for a prolonged period, probably from the early Holocene. This was followed by a multifunctional use of these devices, particularly during the Pastoral Neolithic phase (ca. 6400-3000 cal BC, with the highest concentrations being found near ceremonial contexts related to cattle burials.

  10. Acidic weathering of carbonate building stones: experimental assessment

    Directory of Open Access Journals (Sweden)

    Ryszard Kryza

    2009-06-01

    Full Text Available Three types of carbonate rocks, travertine, limestone and marble have been studied to determine their selected technical parameters (water absorption, resistance to salt crystallization damage and reaction to experimentally modelled acid rain weathering imitating the polluted urban atmospheric conditions. The acidic agents present in natural acid rain precipitation, H2SO4, HCl, HNO3, CH3COOH and mixture of all the acids, “Acid mix”, were tested. The initial stages of acid weathering involve, apart from chemical dissolution, particularly intense physical detachment of rock particles (granular disintegration significantly contributing to the total mass loss. Travertine was found to be most prone to salt crystallization damage and to acid weathering, and these features should be taken into account especially in external architectural usage of this stone in cold climate conditions and polluted urban atmosphere.

  11. The possibilities of using the granodiorite of Kosovska River, village of Chanishte (western Macedonia), as an architectural stone

    International Nuclear Information System (INIS)

    Spasovski, Ortse

    2011-01-01

    The granodiorite of the Kosovska River, western Macedonia, has been examined in order to determine the possibility to be used as an architectural stone. The analyses themselves as well as the laboratory testings have been done on samples of granodiorite. The samples were taken from the surface parts, and the results from their physical and mechanical examination have shown that rock mass itself satisfies all requirements form the use as architectural stone according to the state standards of R. Macedonia. Also the quality of the stone is greater in the deeper parts of the terrain where the influences from the outside have a very small effect. This stone does not have highly decorative features but it has a very fine granual structure which has a positive effect for the technical characteristics and for the being a subject for processing. (Author)

  12. Effect of Tamsulosin on Stone Passage for Ureteral Stones: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Wang, Ralph C; Smith-Bindman, Rebecca; Whitaker, Evans; Neilson, Jersey; Allen, Isabel Elaine; Stoller, Marshall L; Fahimi, Jahan

    2017-03-01

    Tamsulosin is recommended for patients receiving a diagnosis of a ureteral stone less than 10 mm who do not require immediate urologic intervention. Because of conflicting results from recent meta-analyses and large randomized controlled trials, the efficacy of tamsulosin is unclear. We perform a systematic review and meta-analysis to investigate the effect of tamsulosin on stone passage in patients receiving a diagnosis of ureteral stone. MEDLINE, EMBASE, and CENTRAL databases were searched without language restriction through November 2015 for studies assessing the efficacy of tamsulosin and using a double-blind, randomized, controlled trial design. Meta-analysis was conducted with a random-effects model and subgroup analyses were conducted to determine sources of heterogeneity. Eight randomized controlled trials (N=1,384) contained sufficient information for inclusion. The pooled risk of stone passage in the tamsulosin arm was 85% versus 66% in the placebo arm, but substantial heterogeneity existed across trials (I 2 =80.2%; Ptamsulosin (risk difference=22%; 95% confidence interval 12% to 33%; number needed to treat=5). The meta-analysis of the small stone subgroup (Tamsulosin significantly improves stone passage in patients with larger stones, whereas the effect of tamsulosin is diminished in those with smaller stones, who are likely to pass their stone regardless of treatment. Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

  13. Chapter G: Tentative Correlation Between CIPW Normin pl (Total Plagioclase) and Los Angeles Wear in Precambrian Midcontinental Granites-Examples from Missouri and Oklahoma, with Applications and Limitations for Use

    Science.gov (United States)

    Davis, George H.

    2004-01-01

    The normative chemical classification of Cross, Iddings, Pirsson, and Washington (CIPW) is commonly used in igneous petrology to distinguish igneous rocks by comparing their magmatic chemistries for similar and dissimilar components. A potential use for this classification other than in petrologic studies is in the rapid assessment of aggregate sources, possibly leading to an economic advantage for an aggregate producer or user, by providing the opportunity to determine whether further physical testing of an aggregate is warranted before its use in asphalt or concrete pavement. However, the CIPW classification currently should not be substituted for the physical testing required in specifications by State departments of transportation. Demands for physical testing of aggregates have increased nationally as users seek to maximize the quality of the aggregate they purchase for their pavements. Concrete pavements are being laid with increased thicknesses to withstand increasing highway loads. New pavement mixes, most notably Superior Performance Asphalt Pavement ('Superpave'), are designed for additional service life. For both concrete and asphalt, the intent is to generate a durable pavement with a longer service life that should decrease overall life-cycle costs. Numerous aggregate producers possess chemical-composition data available for examination to answer questions from the potential user. State geological surveys also possess chemical-composition data for stone sources. Paired with the results of physical testing, chemical- composition data provide indicative information about stone durability and aggregate strength. The Missouri Department of Transportation has noted a possible relation among coarse-grained Precambrian granites of the midcontinental region, correlating the results of abrasion testing with the contents of normative minerals, also known as normins, calculated from chemical composition data. Thus, normin pl ( total plagioclase) can predict, by

  14. Rock Testing Handbook (Test Standards 1993)

    Science.gov (United States)

    1993-01-01

    relatively inert granular angle of shear resistance-see angle of internal friction. mineral material, such as sand, gravel, slag , crushed stone, angle of...by bleeding. another species, blocking -wood blocks placed between the excavated sur- batch-in growing, quantity of grout mixed at one time. face of a...layer of revetment . lowering electrodes into the hole and measuring any of the failure (in rocks)-cxceeding the maximum strength of the. various

  15. Purbeck Stone - A possible Global Heritage Stone from England

    Science.gov (United States)

    Marker, Brian

    2014-05-01

    By definition, a Global Heritage Stone Resource (GHSR) should have international significance. The Purbeck Group of uppermost Jurassic to lowermost Cretaceous age (Tithonian- Berriasian) outcrops mainly in the Purbeck area of Dorset, England. It was deposited in shallow freshwater to brackish lagoons with occasional marine incursions. Limestones, mainly biosparites, occur at 6 main levels. Differences in bed thickness, jointing and hardness make it suitable for a variety of purposes including dimension stone, monumental and ornamental stone, roofing tiles, paving, flooring and rockery stone. Near the top of the sequence is a dark gastropod biosparite, traditionally called Purbeck Marble, easily carved, which has been extensively used for decorative interior work in churches and cathedrals particularly for fonts, tombs, flooring and facings on columns for example in the medieval cathedrals of Salisbury, Exeter, Durham, York and Wells and Worcester and Westminster Abbey. The stone was extracted at least from Roman times (1st century AD) through the medieval period. Quarrying expanded from about 1700 reaching a peak in the late 18th and 19th centuries. Stone was transported first by sea but later by rail for wider use. Used in many local buildings, it gives an important element of local character. Many of the villages are designated conservation areas with a requirement for repair, maintenance and new building using local stone. Initially the stone was taken from quarries but was later mined. The number of operating companies declined from 15 to 5 over the past 40 years, with 10 active small quarries. Outputs are from few hundred tonnes to a few thousand tonnes per annum or about 9 to 12 years of permitted reserves but the Planning Authority intends to make sufficient provision for production at recent levels for their development plan period. The extraction sites are in an Area of Outstanding Natural Beauty and close to Jurassic Coast World Heritage Site. This might

  16. The OSMATER project: promotion of stone materials from the Verbano-Cusio-Ossola region (Italy) and the Canton Ticino (Switzerland).

    Science.gov (United States)

    Cavallo, Alessandro; Antonella Dino, Giovanna

    2013-04-01

    The OSMATER (sub-Alpine Observatory Materials Territory Restoration) project, funded by the Piedmont Region (Italy) and the European Community, involved four Italian scientific bodies (Polytechnic of Turin, University of Turin, University of Milan-Bicocca, University of Bologna) and Switzerland (SUPSI). The aim was to investigate the present and historical quarrying and processing activities in the cross-border area between the Ossola Valley (Italy) and the Canton Ticino (Switzerland), and the use of dimension stones in local and national architecture. These materials are in many ways a "unique case", for their abundance and lithological variety. In the past, their extraction, processing and application characterized in a decisive way the architectural and constructive culture, both in terms of prestigious architecture and civil buildings, establishing a relationship between "stones and culture", "territory and its resources". In recent years, many of these traditions are losing importance and interest: this results in a loss of knowledge and historical memory, due mainly to the drastic changes in the market. The loss of this knowledge is likely to become irreversible in the short term, with the disappearance of people and social groups depositary of tradition. We can deduce that the creation of an "observatory", like OSMATER, is desirable and essential indeed, if we want to preserve the historical memory of the stone industry of an entire production area. The OSMATER project aimed the knowledge, recovery and enhancement of the architectural and cultural heritage of the cross-border area, through the census and classification of rocks, quarries (both active and historical - since Roman age), monuments and construction techniques typical of the sub-Alpine region, in order to create a documentation centre through a dedicated website. The first phase of the project was devoted to the identification of architectural works built with stone materials, with particular

  17. Influence of mineralogy and moisture content on plasticity and induced anisotropic damage of a clay-stone: application to nuclear waste disposals

    International Nuclear Information System (INIS)

    Chiarelli, A.S.; Sibai, M.; Karami, M.; Ledesert, B.; Hoteit, N.

    2000-01-01

    The influence of mineralogy and moisture content on mechanical behaviour of a clay-stone rock is studied by the way of uniaxial and triaxial compression tests and microscopic observations. Some parameters characteristic of phenomena like plasticity and induced anisotropic damage are discussed as a function of these two factors. Rock behaviour becomes more brittle when calcite content grows or when clay or moisture content decreases. At the micro-level, plasticity is induced by slip of clay sheets and induced anisotropic damage appears by growth of oriented microcracks at the interface between grains and matrix. (authors)

  18. Characterization and utilization potential of basalt rock from East-Lampung district

    Science.gov (United States)

    Isnugroho, K.; Hendronursito, Y.; Birawidha, D. C.

    2018-01-01

    The aim of this research was to study the petrography and chemical properties of basalt rock from East Lampung district, Lampung province. Petrography analysis was performed using a polarization microscope, and analysis of chemical composition using X-RF method. From the analysis of basalt rock samples, the mineral composition consists of pyroxene, plagioclase, olivine, and opaque minerals. Basic mass of basalt rock samples is, composed of plagioclase and pyroxene with subhedral-anhedral shape, forming intergranular texture, and uniform distribution. Mineral plagioclase is colorless and blade shape, transformed into opaque minerals with a size of basalt rock samples, consisting of 37.76-59.64 SiO2; 10.10-20.93 Fe2O3; 11.77-14.32 Al2O3; 5.57-14.75 CaO; 5.37-9.15 MgO; 1.40-3.34 Na2O. From the calculation, obtained the value of acidity ratio (Ma) = 3.81. With these values, indicate that the basalt rock from East Lampung district has the potential to be utilized as stone wool fiber.

  19. Crushed aggregate-betonite mixtures as backfill material for the Finnish repositories of low- and intermediate-level radioactive wastes

    International Nuclear Information System (INIS)

    Holopainen, P.; Pirhonen, V.; Snellman, M.

    1984-03-01

    Backfill materials consisting of three components: crushed rock aggregate, finely ground rock aggregate and bentonite (3 to 2 per cent of weight) were studied. The production and installation procedures of the material were evaluated. Laboratory tests were made to determine the hydraulic conductivity and swelling potential of the materials. Chemical tests were made on the different materials and groundwaters. Mineralogical changes of the clay fraction were estimated. (author)

  20. Assessment and Evaluation of Volcanic Rocks Used as Construction ...

    African Journals Online (AJOL)

    Tesfaye

    as engineering material throughout the world as aggregates in cement concrete, ... properties directly affect the mechanical behavior of the rock in question. ... As the physical and mechanical tests determined the usability of the geological.

  1. Correlation between Copper, Zinc and some lipids in serum, bile and stones of patients with gall stone disease

    International Nuclear Information System (INIS)

    Abu-Farsakh, F.

    1997-01-01

    Measurements of Cu, Zn and some lipid concentrations were carried out in serum, bile and gall stone samples collected from 76 patients undergoing surgery for removal of gall stones. The results showed that Cu and Zn were present in micromolar concentration in bile (average Cu concentration = 13.4 ± 0.92, average Zn concentration = 13.4 ± 1.05) and gall stones (average Cu concentration = 2.8 ± 0.16, average Zn concentration = 1.8 ± 0.16 mmol/ g stone). Cross-tabulation of the results showed significant positive linear correlations (p< 0.01) between stone Zn vs. bile cholesterol (r = 0.253), stone Zn vs. bile bilirubin (r = 0.396) (in mixed stones only). This suggested that the more hydrophobic the bile sample, the more Zn co-precipitate with cholesterol or bilirubin. (author). 17 refs., 3 tabs

  2. Determination of weathering and conservation of sculptured stone by use of the laser method

    International Nuclear Information System (INIS)

    Aaberg, G.; Stijfhoorn, D.E.

    1996-09-01

    Weathering and deterioration of sculptured stone and masonry is a natural process which stars at the same moment the stone is quarried and exposed to exogenous conditions. This process of natural decay has, however, been accelerated due to the emission of different man-made pollutants, domestic and industrial, local and global. The ISOLASER project is based on the laser microprobe technique for determining the depth of natural and induced weathering and the effect of conservation measures of cultural objects of carbonaceous sandstone and marble/limestone. The purpose of the project is to determine the depth of weathering and depth of penetration of conservation agents in unweathered calcite-cemented stone and the weathering profile in linseed oil-treated stone after accelerated weathering cycles in a climatic chamber. The analytical results show that even after such a short period as five weeks of exposure the effect of SO 2 , NO 2 and elevated humidity on Gotland sandstone can be easily observed in a change of the δ 13 C values in the outermost 2 mm of the stone. Treating the sample with linseed oil has a preserving effect on the rock and hinders the deteriorating effect of SO 2 and NO 2 . The oil treatment even preserves the signature of previously incorporated organic carbon. Compilation of a questionnaire representing a broad field within natural sciences in cultural heritage research in Europe, shows an overwhelming positive approach to the project as such. The questioned researchers consider the laser method particularly useful as a complementary method in other investigations and states that the method can without doubt give new dimensions to the analysis of important cultural objects. 2 refs., 6 figs

  3. Acute management of stones

    DEFF Research Database (Denmark)

    Jung, Helene; Osther, Palle J S

    2015-01-01

    INTRODUCTION: Stone management is often conservative due to a high spontaneous stone passage rate or non-symptomatic calyceal stones that do not necessarily require active treatment. However, stone disease may cause symptoms and complications requiring urgent intervention. MATERIAL AND METHODS: I...... with careful consideration of stone size and location, symptoms, patient comorbidity and radiation dose. CONCLUSION: In case of infective hydronephrosis, compromised renal function or persistent pain despite adequate analgesic treatment acute intervention is indicated....

  4. The ultrasonic technique for in situ investigations on stones: suggestions for uses

    Science.gov (United States)

    Bellopede, R.; Marini, P.

    2012-04-01

    The Ultrasound Pulse Velocity (UPV) is one of the main non destructive techniques to detect both in laboratory and in situ the stone decay and many international papers of the recent years deal with its application. This technique is often executed in laboratory, where the possibility to keep constant the environmental and test conditions are a guarantee of the reliability of the results. It is known in fact the UPV are mainly conditioned by the following factors: - the characteristics of the stone tested (not only petrographic properties such as texture and structure, but even specimen dimension and water content); - the transducers features such as frequency, divergence angle , near field and wavelength; - external climate factors such as environmental temperature, humidity. In spite of the many factors affecting the measurements, UPV performed in laboratory is well correlated with mechanical strength of the stone , with its porosity and, as consequence, it is a reliable technique to detect the durability of a stone. On the other side, for in situ UPV test it is important to take into account that the measurement uncertainty is affected by the unknown water content in the stone. From tests performed on different rocks (marble, limestones, travertines, granites, gneiss, schists , sandstones) , the ratios between UPV tested in dry and saturated conditions can be > 1 or stone in order to choose the suitable measurement frequency; the correct choice of transducers frequencies; the use of a reference slab, with a known UPV in dry conditions, to be exposed in the investigated site some days before the in situ tests, in order to appreciate the UPV variation due to climate factors.

  5. Treatment of gallbladder stone with common bile duct stones in the laparoscopic era

    OpenAIRE

    Zhang, Wei-jie; Xu, Gui-fang; Huang, Qin; Luo, Kun-lun; Dong, Zhi-tao; Li, Jie-ming; Wu, Guo-zhong; Guan, Wen-xian

    2015-01-01

    Background: Laparoscopic common bile duct exploration (LCBDE) for stone can be carried out by either laparoscopic transcystic stone extraction (LTSE) or laparoscopic choledochotomy (LC). It remains unknown as to which approach is optimal for management of gallbladder stone with common bile duct stones (CBDS) in Chinese patients. Methods: From May 2000 to February 2009, we prospective treated 346 consecutive patients with gallbladder stones and CBDS with laparoscopic cholecystectomy and LCBDE....

  6. Assessment of the Alteration of Granitic Rocks and its Influence on Alkalis Release

    Science.gov (United States)

    Ferraz, Ana Rita; Fernandes, Isabel; Soares, Dora; Santos Silva, António; Quinta-Ferreira, Mário

    2017-12-01

    Several concrete structures had shown signs of degradation some years after construction due to internal expansive reactions. Among these reactions there are the alkali-aggregate reactions (AAR) that occur between the aggregates and the concrete interstitial fluids which can be divided in two types: the alkali-silica reaction (ASR) and alkali-carbonate reaction (ACR). The more common is the ASR which occurs when certain types of reactive silica are present in the aggregates. In consequence, an expansive alkali-silica gel is formed leading to the concrete cracking and degradation. Granites are rocks composed essentially of quartz, micas and feldspars, the latter being the minerals which contain more alkalis in their structure and thus, able to release them in conditions of high alkalinity. Although these aggregates are of slow reaction, some structures where they were applied show evidence of deterioration due to ASR some years or decades after the construction. In the present work, the possible contribution of granitic aggregates to the interstitial fluids of concrete by alkalis release was studied by performing chemical attack with NaOH and KOH solutions. Due to the heterogeneity of the quarries in what concerns the degree of alteration and/or fracturing, rock samples with different alteration were analysed. The alteration degree was characterized both under optical microscope and image analysis and compared with the results obtained from the chemical tests. It was concluded that natural alteration reduces dramatically the releasable alkalis available in the rocks.

  7. Use of the probability of stone formation (PSF) score to assess stone forming risk and treatment response in a cohort of Brazilian stone formers

    OpenAIRE

    Turney, Benjamin; Robertson, William; Wiseman, Oliver; Amaro, Carmen Regina P. R.; Leitão, Victor A.; Silva, Isabela Leme da; Amaro, João Luiz

    2014-01-01

    Introduction: The aim was to confirm that PSF (probability of stone formation) changed appropriately following medical therapy on recurrent stone formers.Materials and Methods: Data were collected on 26 Brazilian stone-formers. A baseline 24-hour urine collection was performed prior to treatment. Details of the medical treatment initiated for stone-disease were recorded. A PSF calculation was performed on the 24 hour urine sample using the 7 urinary parameters required: voided volume, oxalate...

  8. A group of 20 stone anchors from the waters of Dwarka, on the Gujarat Coast, India

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S; Sundaresh; Tripati, S.; Gudigar, P.; Vora, K.H.; Bandodkar, S.N.

    A large number of stone anchors were discovered in a water depth of 10-14 m off Dwarka during the 1998-99 season. The seabed near the anchors consists of a ledge with an average height of 1 m. Several anchors were found trapped between the rocks...

  9. Economic and Environmental Evaluation and Optimal Ratio of Natural and Recycled Aggregate Production

    Directory of Open Access Journals (Sweden)

    Milad Ghanbari

    2017-01-01

    Full Text Available Steady increase in overexploitation of stone quarries, generation of construction and demolition waste, and costs of preparing extra landfill space have become environmental and waste management challenges in metropolises. In this paper, aggregate production is studied in two scenarios: scenario 1 representing the production of natural aggregates (NA and scenario 2 representing the production of recycled aggregates (RA. This study consists of two parts. In the first part, the objective is the environmental assessment (energy consumption and CO2 emission and economic (cost evaluation of these two scenarios, which is pursued by life-cycle assessment (LCA method. In the second part, the results of the first part are used to estimate the optimal combination of production of NA and RA and thereby find an optimal solution (scenario for a more eco-friendly aggregate production. The defined formulas and relationship are used to develop a model. The results of model validation show that the optimal ratio, in optimal scenario, is 50%. The results show that, compared to scenario 1, optimal scenario improves the energy consumption, CO2 emissions, and production cost by, respectively, 30%, 36%, and 31%, which demonstrate the effectiveness of this optimization.

  10. Kidney Stones (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Kidney Stones KidsHealth / For Parents / Kidney Stones What's in ... other treatments to help remove the stones. How Kidney Stones Form It's the kidneys' job to remove ...

  11. Environmentalism and natural aggregate mining

    Science.gov (United States)

    Drew, L.J.; Langer, W.H.; Sachs, J.S.

    2002-01-01

    Sustaining a developed economy and expanding a developing one require the use of large volumes of natural aggregate. Almost all human activity (commercial, recreational, or leisure) is transacted in or on facilities constructed from natural aggregate. In our urban and suburban worlds, we are almost totally dependent on supplies of water collected behind dams and transported through aqueducts made from concrete. Natural aggregate is essential to the facilities that produce energy-hydroelectric dams and coal-fired powerplants. Ironically, the utility created for mankind by the use of natural aggregate is rarely compared favorably with the environmental impacts of mining it. Instead, the empty quarries and pits are seen as large negative environmental consequences. At the root of this disassociation is the philosophy of environmentalism, which flavors our perceptions of the excavation, processing, and distribution of natural aggregate. The two end-member ideas in this philosophy are ecocentrism and anthropocentrism. Ecocentrism takes the position that the natural world is a organism whose arteries are the rivers-their flow must not be altered. The soil is another vital organ and must not be covered with concrete and asphalt. The motto of the ecocentrist is "man must live more lightly on the land." The anthropocentrist wants clean water and air and an uncluttered landscape for human use. Mining is allowed and even encouraged, but dust and noise from quarry and pit operations must be minimized. The large volume of truck traffic is viewed as a real menace to human life and should be regulated and isolated. The environmental problems that the producers of natural aggregate (crushed stone and sand and gravel) face today are mostly difficult social and political concerns associated with the large holes dug in the ground and the large volume of heavy truck traffic associated with quarry and pit operations. These concerns have increased in recent years as society's demand for

  12. Applications of some non destructive testing techniques to the characterization of calcareous rocks: ultrasounds, X and gamma-ray radiography, tomography, neutron radiography

    International Nuclear Information System (INIS)

    Sicardy, O.

    1986-02-01

    NUCLEART Laboratory has been developping various techniques of conservation of art objects made of wood or stone. It has, among others, achieved a technique of strengthening porous stone objects, by resin impregnation followed by polymerization under gamma rays. The good conduct of such operations implies the existence of characterization means, before and after treatment of the objects. Two means of rocks characterization have been studied: - ultrasound techniques, - radiography techniques. The first part consists in a general description of the calcareous rocks morphology and a presentation of the studied specimens. The second part deals with the application of ultrasound techniques to rocks. Experimentally, one pays particular attention to the specific aspects of ultrasounds propagation inside materials like porous rocks, and especially diffusion phenomena. Results were interpreted in terms of propagation medium structure. Practical interest for rocks control through such techniques has been underligned. The third part concerns the application of radiographic techniques to calcareous rocks. Experimental work consists in establishing exposure curves for a wide range of energy, and the images quality determination. Through a statistics approach, and using digitalization techniques, one has done an exhaustive study of the radiographic noise. Moreover two techniques close to conventional radiography were explored: neutron radiography and X-ray tomography. Their specificity and interest in the case of calcareous rocks have been shown [fr

  13. Papillary Ductal Plugging is a Mechanism for Early Stone Retention in Brushite Stone Disease

    DEFF Research Database (Denmark)

    Williams, James C; Borofsky, Michael S; Bledsoe, Sharon B

    2018-01-01

    PURPOSE: Mechanisms of early stone retention in the kidney are under studied and poorly understood. To date attachment via Randall's plaque is the only widely accepted theory in this regard, which is best described in idiopathic calcium oxalate stone formers. Brushite stone formers are known...... to have distinct papillary morphology relative to calcium oxalate stone formers. As such we sought to determine whether stone attachment mechanisms in such patients may be similarly unique. MATERIALS AND METHODS: Patients undergoing percutaneous and or ureteroscopic procedures for stone removal consented...... to endoscopic renal papillary examination and individual stone collection. Each removed stone was processed using micro computerized tomography to assess the 3-dimensional microstructure and the minerals contained, and search for common structural features indicative of novel mechanisms of early growth...

  14. Dietary Plants for the Prevention and Management of Kidney Stones: Preclinical and Clinical Evidence and Molecular Mechanisms

    Science.gov (United States)

    Nirumand, Mina Cheraghi; Hajialyani, Marziyeh; Rahimi, Roja; Farzaei, Mohammad Hosein; Nabavi, Seyed Mohammad

    2018-01-01

    Kidney stones are one of the oldest known and common diseases in the urinary tract system. Various human studies have suggested that diets with a higher intake of vegetables and fruits play a role in the prevention of kidney stones. In this review, we have provided an overview of these dietary plants, their main chemical constituents, and their possible mechanisms of action. Camellia sinensis (green tea), Rubus idaeus (raspberry), Rubia cordifolia (common madder), Petroselinum crispum (parsley), Punica granatum (pomegranate), Pistacia lentiscus (mastic), Solanum xanthocarpum (yellow-fruit nightshade), Urtica dioica (stinging nettle), Dolichos biflorus (horse gram), Ammi visnaga (khella), Nigella sativa (black-cumin), Hibiscus sabdariffa (roselle), and Origanum vulgare (oregano) have received considerable interest based on scientific evidence. Beside these dietary plants, phytochemicals—such as catechin, epicatechin, epigallocatechin-3-gallate, diosmin, rutin, quercetin, hyperoside, and curcumin—as antioxidant dietary phyto-phenols were found to be effective for the prevention of urolithiasis (the process of stone formation in the urinary tract). The main underlying mechanisms of these dietary plants and their isolated phytonutrients in the management of urolithiasis include diuretic, antispasmodic, and antioxidant activity, as well as an inhibitory effect on crystallization, nucleation, and aggregation of crystals. The results as presented in this review demonstrate the promising role of dietary plants and phytophenols in the prevention and management of kidney stones. Further investigations are required to confirm the safety and efficacy of these compounds. PMID:29518971

  15. Dietary Plants for the Prevention and Management of Kidney Stones: Preclinical and Clinical Evidence and Molecular Mechanisms.

    Science.gov (United States)

    Nirumand, Mina Cheraghi; Hajialyani, Marziyeh; Rahimi, Roja; Farzaei, Mohammad Hosein; Zingue, Stéphane; Nabavi, Seyed Mohammad; Bishayee, Anupam

    2018-03-07

    Kidney stones are one of the oldest known and common diseases in the urinary tract system. Various human studies have suggested that diets with a higher intake of vegetables and fruits play a role in the prevention of kidney stones. In this review, we have provided an overview of these dietary plants, their main chemical constituents, and their possible mechanisms of action. Camellia sinensis (green tea), Rubus idaeus (raspberry), Rubia cordifolia (common madder), Petroselinum crispum (parsley), Punica granatum (pomegranate), Pistacia lentiscus (mastic), Solanum xanthocarpum (yellow-fruit nightshade), Urtica dioica (stinging nettle), Dolichos biflorus ( horse gram ), Ammi visnaga (khella), Nigella sativa (black-cumin), Hibiscus sabdariffa (roselle), and Origanum vulgare (oregano) have received considerable interest based on scientific evidence. Beside these dietary plants, phytochemicals-such as catechin, epicatechin, epigallocatechin-3-gallate, diosmin, rutin, quercetin, hyperoside, and curcumin-as antioxidant dietary phyto-phenols were found to be effective for the prevention of urolithiasis (the process of stone formation in the urinary tract). The main underlying mechanisms of these dietary plants and their isolated phytonutrients in the management of urolithiasis include diuretic, antispasmodic, and antioxidant activity, as well as an inhibitory effect on crystallization, nucleation, and aggregation of crystals. The results as presented in this review demonstrate the promising role of dietary plants and phytophenols in the prevention and management of kidney stones. Further investigations are required to confirm the safety and efficacy of these compounds.

  16. Dietary Plants for the Prevention and Management of Kidney Stones: Preclinical and Clinical Evidence and Molecular Mechanisms

    Directory of Open Access Journals (Sweden)

    Mina Cheraghi Nirumand

    2018-03-01

    Full Text Available Kidney stones are one of the oldest known and common diseases in the urinary tract system. Various human studies have suggested that diets with a higher intake of vegetables and fruits play a role in the prevention of kidney stones. In this review, we have provided an overview of these dietary plants, their main chemical constituents, and their possible mechanisms of action. Camellia sinensis (green tea, Rubus idaeus (raspberry, Rubia cordifolia (common madder, Petroselinum crispum (parsley, Punica granatum (pomegranate, Pistacia lentiscus (mastic, Solanum xanthocarpum (yellow-fruit nightshade, Urtica dioica (stinging nettle, Dolichos biflorus (horse gram, Ammi visnaga (khella, Nigella sativa (black-cumin, Hibiscus sabdariffa (roselle, and Origanum vulgare (oregano have received considerable interest based on scientific evidence. Beside these dietary plants, phytochemicals—such as catechin, epicatechin, epigallocatechin-3-gallate, diosmin, rutin, quercetin, hyperoside, and curcumin—as antioxidant dietary phyto-phenols were found to be effective for the prevention of urolithiasis (the process of stone formation in the urinary tract. The main underlying mechanisms of these dietary plants and their isolated phytonutrients in the management of urolithiasis include diuretic, antispasmodic, and antioxidant activity, as well as an inhibitory effect on crystallization, nucleation, and aggregation of crystals. The results as presented in this review demonstrate the promising role of dietary plants and phytophenols in the prevention and management of kidney stones. Further investigations are required to confirm the safety and efficacy of these compounds.

  17. Geomorphology's role in the study of weathering of cultural stone

    Science.gov (United States)

    Pope, Gregory A.; Meierding, Thomas C.; Paradise, Thomas R.

    2002-10-01

    Great monumental places—Petra, Giza, Angkor, Stonehenge, Tikal, Macchu Picchu, Rapa Nui, to name a few—are links to our cultural past. They evoke a sense of wonderment for their aesthetic fascination if not for their seeming permanence over both cultural and physical landscapes. However, as with natural landforms, human constructs are subject to weathering and erosion. Indeed, many of our cultural resources suffer from serious deterioration, some natural, some enhanced by human impact. Groups from the United Nations to local civic and tourism assemblies are deeply interested in maintaining and preserving such cultural resources, from simple rock art to great temples. Geomorphologists trained in interacting systems, process and response to thresholds, rates of change over time, and spatial variation of weathering processes and effects are able to offer insight into how deterioration occurs and what can be done to ameliorate the impact. Review of recent literature and case studies presented here demonstrate methodological and theoretical advances that have resulted from the study of cultural stone weathering. Because the stone was carved at a known date to a "baseline" or zero-datum level, some of the simplest methods (e.g., assessing surface weathering features or measuring surface recession in the field) provide useful data on weathering rates and processes. Such data are difficult or impossible to obtain in "natural" settings. Cultural stone weathering studies demonstrate the importance of biotic and saline weathering agents and the significance of weathering factors such as exposure (microclimate) and human impact. More sophisticated methods confirm these observations, but also reveal discrepancies between field and laboratory studies. This brings up two important caveats for conservators and geomorphologists. For the conservator, are laboratory and natural setting studies really analogous and useful for assessing stone damage? For the geomorphologist, does

  18. Simplified methods for the evaluation of the risk of forming renal stones and the follow-up of stone-forming propensity during the preventive treatment of stone-formation.

    Science.gov (United States)

    Grases, Fèlix; Costa-Bauzá, Antonia

    2016-02-01

    Renal lithiasis is a complex multifactorial disease in which recurrence is common. Thus, simple and reliable procedures are needed to evaluate patients with previous kidney stones to determine the risk of recurrence. In this paper we review simple biochemical procedures that can be used to determine the risk for renal stone formation when the stone is available or unavailable for analysis. Our present knowledge of renal lithiasis indicates that renal stones form due to several well-defined factors. Analysis of the renal stone itself can provide important information about clinical factors that require further investigation. When the stone is unavailable, it is necessary to perform a general evaluation of main urinary risk factors associated to renal stone formation, but this study should be complemented considering information related to direct familial antecedents, recidivant degree, radiological images, medical history, and life style habits. Finally, tools for patient follow-up of stone-forming propensity during the preventive treatment are discussed .

  19. Humidity sorption on natural building stone

    Science.gov (United States)

    Franzen, C.; Mirwald, P.

    2003-04-01

    processes, physical, chemical or biological, depend on the presence of water. Like most porous materials building stone respond on humidity by water uptake. The sorption isotherm represents the equilibrium moisture, specific for each material. The determination of the isotherm for stone of low and small porosity like marble is difficult. With the help of a newly developed water sorption analysis chamber [2], which allows the simultaneous measurement of 11 samples, good results on stone/rock samples have been obtained. Even at marble species with pore volumes lower than 0.4 % isotherms are measured. This analytical method offers new insights in the pore behaviour of low porosity materials. The advantages of this technique which supplements other techniques (e.g. BET, Hg-porosimetry) are: i) the testing agent is identical to the weathering agent, water; ii) the atmospheric parameters at the measurement reflect the natural conditions - thus no changes to the material properties have to be considered; iii) due to the small diameter of the water molecule (~0.28 nm), smaller pores are reached than e.g. with N2 (~0.31 nm). Sorption isotherms of sandstone (Baumberg, Obernkirchen, Groeden), granite (Brixen), and marble (Sterzing, Laas) are presented. Particular as to marbles the resolution is considerably higher. A previously observed negative hysteresis [3] seems an effect due to limited data resolution. [1] Snethlage, R. (1984) Steinkonservierung, Bayer. LA Denkmalpflege, Ah. 22, 203 S. [2] Griesser, U.J., Dillenz, J. (2002) Neuartiges, vollautomatisches Feuchtesorptionsprüfgerät mit hohem Probendurchsatz, Feuchtetag 2002, Weimar, 85-93. [3] Fimmel, R. (1996) Verwitterungsverhalten der alpinen Marmore von Laas und Sterzing, Diss. Univ. Ibk, 116 S.

  20. Role of clay constituents in stone decay processes

    Directory of Open Access Journals (Sweden)

    Veniale, F.

    2001-12-01

    Full Text Available Stone alterability/durability is depending upon a number of intrinsic and extrinsic factors among which "clay minerals" constituents, either diffused throughout the stone framework or as coating-filling of void spaces, can play an important role. Swelling-shrinking and aggregation-disaggregation phenomena occurring by interaction of argillaceous particles with water and other fluids can cause destructuration of the stone resulting in a variety of pathologies. Also salt crystallization which is depending on fluid transfer, moisture evaporation and ion concentration in the circulating solutions, can be influenced by clay mineral reactivity. Furthermore, saline solutions can drastically change the clay minerals behaviour, resulting in enhanced "osmotic" swelling and variations in clay aggregation geometry; these phenomena resulting in significant stone damage. Case histories concerning several lithotypes used for monumental buildings and artistic manufacts are reported for showing the role of different clay mineral types in determining trend and intensity of decay processes.

    Varios factores, tanto intrínsecos como extrínsecos, pueden condicionar la alterabilidad/durabilidad de materiales pétreos. Entre ellos, la presencia de minerales arcillosos, bien como constituyentes difusos o recubriendo-rellenando huecos, puede jugar un papel importante. El resultado de la interacción de las partículas arcillosas y el agua (u otros fluidos da lugar a patologías que son consecuencia de una serie de daños internos producidos por las continuas variaciones plásticas, asociadas a parámetros físicos y cristaloquímicos de este tipo de minerales. Entre los que podemos citar la desestructuración de la piedra (bien por agregación-desagregación de las partículas arcillosas o por procesos de hinchamiento-contracción que está asociado, por ejemplo, con la cristalización de sales, producida por la transferencia de fluidos a su través, o a

  1. The history of aggregate development in the denver, Co area

    Science.gov (United States)

    Langer, W.H.

    2009-01-01

    At the start of the 20th century Denver's population was 203,795. Most streets were unpaved. Buildings were constructed of wood frame or masonry. Transport was by horse-drawn-wagon or rail. Statewide, aggregate consumption was less than 0.25 metric tons per person per year. One hundred years later Denver had a population of 2,365,345. Today Denver is a major metropolitan area at the crossroads of two interstates, home to a new international airport, and in the process of expanding its light rail transit system. The skyline is punctuated with skyscrapers. The urban center is surrounded with edge cities. These changes required huge amounts of aggregate. Statewide, aggregate consumption increased 50 fold to over 13 metric tons per person per year. Denver has a large potential supply of aggregate, but sand and gravel quality decreases downstream from the mountain front and potential sources of crushed stone occur in areas prized for their scenic beauty. These issues, along with urban encroachment and citizen opposition, have complicated aggregate development and have paved a new path for future aggregate development including sustainable resource management and reclamation techniques.

  2. Clay club catalogue of characteristics of argillaceous rocks

    International Nuclear Information System (INIS)

    2005-01-01

    The OECD/NEA Working Group on the Characterisation, the Understanding and the Performance of Argillaceous Rocks as Repository Host Formations, namely the Clay Club, examines the various argillaceous rocks that are being considered for the deep geological disposal of radioactive waste, i.e. from plastic, soft, poorly indurated clays to brittle, hard mud-stones or shales. The Clay Club considered it necessary and timely to provide a catalogue to gather in a structured way the key geo-scientific characteristics of the various argillaceous formations that are - or were - studied in NEA member countries with regard to radioactive waste disposal. The present catalogue represents the outcomes of this Clay Club initiative. (author)

  3. Archaeomagnetic studies of Maori Hangi Stones from New Zealand

    Science.gov (United States)

    Kinger, R.; Turner, G. M.; McFadgen, B.

    2014-12-01

    Global palaeosecular variation models still suffer from a paucity of high quality data from the SW Pacific region. Over the past two years we have worked to fill this gap with archaeomagnetic data - directions and palaeointensities - by studying the thermoremanent magnetization of Maori hangi cooking stones. Used as heat retainers, these stones are heated, frequently above the Curie temperatures of constituent magnetic minerals, before being buried in earth ovens. After removal of the food, hangi sites are often abandoned with the stones still in situ, carrying a record of the magnetic field in which they were last cooled. We have sampled a range of archaeological hangi sites throughout New Zealand, dating to early prehistoric times (ca 700 BP). The stones vary in lithology from andesites, originating from the central North Island volcanoes, favoured by Maori for their durability and with NRM intensities up to 30 A/m, to greywackes and schists from the main axial ranges, with NRMs as weak as 10-4A/m. In all cases, we have independently oriented and retrieved several stones, and we have made several specimens from each stone, either by drilling (standard cylindrical specimens) or sawing (pseudo-cubes) in the laboratory. We have calculated site mean palaeomagnetic directions from principal component analysis of thermal demagnetization data, discarding the data of stones that show evidence of disturbance. We have carried out palaeointensity experiments using a Coe/Thellier method with pTRM and tail checks, and with selection criteria modified to the situation. Rock magnetic experiments contribute to our understanding of the mineralogy, domain state and blocking temperature spectra. The palaeodirections fall between declinations of 348o and 24.5o, and inclinations of -46.4o and -72.4o, with palaeointensities between 43.7±1.4 and 81.3±6.1 mT. Most fall within the expected range of secular variation for New Zealand. However the palaeointensity of 81.34±6.08mT, from an

  4. Retrograde intrarenal stone surgery for extracorporeal shock-wave lithotripsy-resistant kidney stones

    DEFF Research Database (Denmark)

    Jung, Helene; Nørby, Bettina; Osther, Palle Jörn

    2006-01-01

    OBJECTIVE: The newer flexible ureteroscopes, 150-200-microm holmium YAG laser fibres and superflexible Dormia baskets have made it possible to reach and treat stones in all parts of the kidney. The object of this evaluation was to study the outcome of retrograde intrarenal stone surgery (RIRS......) for extracorporeal shock-wave lithotripsy (ESWL)-resistant kidney stones. MATERIAL AND METHODS: A total of 38 consecutive patients (18 males, 20 females) participated in the study. All patients had undergone ESWL prior to RIRS without success. In all cases the stones could be reached with the endoscope. Calculi...... ranged in size from 3 to 20 mm (mean 9 mm). In 32 cases the stones were fragmented using a holmium YAG laser and in six the stones could be extracted using zero-tip Dormia baskets without fragmentation. Sixteen patients had lower calyceal calculi and eight had an abnormal anatomy of the upper urinary...

  5. Diffusivity database (DDB) for major rocks. Database for the second progress report

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Haruo

    1999-10-01

    A database for diffusivity for a data setting of effective diffusion coefficients in rock matrices in the second progress report, was developed. In this database, 3 kinds of diffusion coefficients: effective diffusion coefficient (De), apparent diffusion coefficient (Da) and free water diffusion coefficient (Do) were treated. The database, based on literatures published between 1980 and 1998, was developed considering the following points. (1) Since Japanese geological environment is focused in the second progress report, data for diffusion are collected focused on Japanese major rocks. (2) Although 22 elements are considered to be important in performance assessment for geological disposal, all elements and aquatic tracers are treated in this database development considering general purpose. (3) Since limestone, which belongs to sedimentary rock, can become one of the natural resources and is inappropriate as a host rock, it is omitted in this database development. Rock was categorized into 4 kinds of rocks; acid crystalline rock, alkaline crystalline rock, sedimentary rock (argillaceous/tuffaceous rock) and sedimentary rock (psammitic rock/sandy stone) from the viewpoint of geology and mass transport. In addition, rocks around neutrality among crystalline rock were categorized into the alkaline crystalline rock in this database. The database is composed of sub-databases for 4 kinds of rocks. Furthermore, the sub-databases for 4 kinds of the rocks are composed of databases to individual elements, in which totally, 24 items such as species, rock name, diffusion coefficients (De, Da, Do), obtained conditions (method, porewater, pH, Eh, temperature, atmosphere, etc.), etc. are input. As a result of literature survey, for De values for acid crystalline rock, totally, 207 data for 18 elements and one tracer (hydrocarbon) have been reported and all data were for granitic rocks such as granite, granodiorite and biotitic granite. For alkaline crystalline rock, totally, 32

  6. Kidney stones - self-care

    Science.gov (United States)

    ... self-care; Nephrolithiasis and self-care; Stones and kidney - self-care; Calcium stones and self-care; Oxalate ... provider or the hospital because you have a kidney stone. You will need to take self-care ...

  7. Porous Media and Immersed Boundary Hybrid-Modelling for Simulating Flow in Stone Cover-Layers

    DEFF Research Database (Denmark)

    Jensen, Bjarne; Liu, Xiaofeng; Christensen, Erik Damgaard

    In this paper we present a new numerical modelling approach for coastal and marine applications where a porous media conceptual model was combined with a free surface volume-of-fluid (VOF) model and an immersed boundary method (IBM). The immersed boundary model covers the method of describing....... In this paper, the model is applied to investigate two practical cases in terms of a cover layer of stones on a flat bed under oscillatory flow at different packing densities, and a rock toe structure at a breakwater....

  8. Differences in the surface texture of aggregate particles determined by 3D model derived from optic microscope measurements

    Directory of Open Access Journals (Sweden)

    Jozef Komačka

    2015-12-01

    Full Text Available The surface texture of aggregate particles was investigated based on the 3D model of surface generated from the measurements by optic microscope. New software MicroSYS was developed to determine the wrapping plane of 3D model of aggregate using the function called “Thin plate spline“. New parameter for evaluation of surface texture of aggregate particle was proposed as the volumetric difference between two planes (wrapping plane and aggregate surface. Applicability of this parameters was tested on two aggregate fractions (4/8 and 8/11 coming form 11 quarries in Slovakia. The tested aggregates differed from petrography point of view and ranged from soft to hard. The difference among the quarries and also between fractions of aggregate was found out. The better surface texture was observed for the finner fraction of aggregate. Simultaneously, the better results were determined in the case of aggregate produced from the ingeous intrusive or extrusive rocks comparing to the sedimentary carbonate rocks aggregate.

  9. FEATURES OF ASH OF THERMAL POWER PLANTS AS AGGREGATE FOR CONCRETES

    Directory of Open Access Journals (Sweden)

    M. A. Storozhuk

    2017-10-01

    Full Text Available Purpose. The scientific work is dedicated to development of scientific-technical bases of production and application of concrete on the basis of ashes of thermal power plants (TPP. Methodology. The properties of TPP ash, as well as the peculiarities of its behavior in a concrete mix as a fine aggregate, have been studied. It is shown that the hydrolysis and hydration of cement occur in the active environment of ash, which has a huge specific surface area. This significantly affects the course of these processes and the quality of the concrete produced. A new technology of application of ash of TPP for preparation of concrete mixes is offered. Vibrated and vibrovacuumized concretes of optimum composition from slag and ash, as well as from granite crushed stone and ash, are tested. The chara-cteristics of ordinary concrete (from granite crushed stone and quartz sand are given to compare. Findings. The results of the tests showed the possibility of obtaining concretes of class C20/25…C25/30 on the basis of slag and ash of TPP at a limited consumption of cement. It is shown that the concrete with traditional aggregates has a lower strength than the concrete, which has ash as fine aggregate. This research results contribute to the increased use of ash in construction that solves the problem of aggregates as well as thermal power plants waste recycling. Originality. New method and technology of application of TPP ashes in concrete are developed. Ash concrete mix has rational flowability, which produces the greatest strength of ash vacuum concrete. This strength is twice or more as large as the strength of vibrated ash concrete mix with flowability S1. Practical value. The physico-chemical properties of TPP ash as aggregate for concrete are presented. Significant difference of ash from ordinary aggregates is shown. Chemical activity of the ash is justified. The special conditions of cement hardening in the case of using ash as aggregate for concrete

  10. Engineering Performance of Polyurethane Bonded Aggregates

    Directory of Open Access Journals (Sweden)

    Haimin WU

    2017-08-01

    Full Text Available In this paper the engineering performance of polyurethane (PUR bonded aggregate were studied. The engineering performance, including compressive and flexural mechanical properties, void ratio, and coefficient of permeability were determined through laboratory tests. Moreover, the effects of two different curing conditions on the compressive strength properties of a PUR bonded aggregate were also evaluated. The compressive strengths of PUR bonded aggregates were found to be lower than that of conventional porous concrete, which is a commonly used cushion material. However, experimental results indicated a higher void ratio and coefficient of permeability, lower elasticity modulus, better toughness, and stronger adaptability to flexural deformation compared to porous concrete. Consequently, PUR bonded aggregate is a better solution than porous concrete when used as the cushion material of a geomembrane surface barrier for a high rock-fill dam.DOI: http://dx.doi.org/10.5755/j01.ms.23.2.15798

  11. The relationship between serum and urinary Fetuin-A levels and kidney stone formation among kidney stone patients.

    Science.gov (United States)

    Mehrsai, Abdolrasoul; Guitynavard, Fateme; Nikoobakht, Mohammad Reza; Gooran, Shahram; Ahmadi, Ayat

    2017-01-01

    Mineralization inhibitors are required to prevent the precipitation of minerals and inhibit the formation of kidney stones and other ectopic calcifications. In laboratory studies, Fetuin-A as a glycoprotein has inhibited hydroxyapatite precipitation in calcium and phosphate supersaturated solutions; however, information about patients with kidney stones is limited. The aim of this study was to investigate the association of serum and urinary Fetuin-A levels with calcium oxalate kidney stones. In this case-control study, 30 patients with kidney stones and 30 healthy individuals without any history of urolithiasis who were referred to the urology ward of Sina Hospital of Tehran, Iran, in 2015 were entered into the study. All patients underwent computerized tomography scans. After collecting demographic information, serum and urine levels of Fetuin-A and some other calcification inhibitors and promoters, were measured and compared using T-test, Mann-Whitney and logistic regression between the two study groups. Patients with kidney stones, on average, had lower levels of Serum Fetuin-A (1522.27 ±755.39 vs. 1914.64 ±733.76 μg/ml; P = 0.046) as well as lower levels of Urine Fetuin-A (944.62 ±188.5 vs. 1409.68 ±295.26 μg/ml; P <0.001). Multivariate logistic analysis showed that urinary calcium and serum creatinine are the risk factors and Fetuin-A is a urinary protective factor for kidney stones. PFC Our study showed that patients with kidney stones had lower serum and urinary levels of Fetuin-A. In the logistic regression model, urinary Fetuin-A was reported as a protective factor for kidney stones.

  12. Canada's National Building Stone: Tyndall Stone from Manitoba

    Science.gov (United States)

    Pratt, Brian R.; Young, Graham A.; Dobrzanski, Edward P.

    2016-04-01

    Tyndall Stone is a distinctively mottled and highly fossiliferous dolomitic limestone that belongs to the Selkirk Member of the Red River Formation, of Late Ordovician (Katian) age. It has been quarried at Garson, Manitoba, 37 km northeast of Winnipeg, since 1895, although other quarries in the area go back to 1832. Tyndall Stone, so named because it was shipped by rail from nearby Tyndall, is currently produced by Gillis Quarries Limited. It has various uses as a dimension stone. Large slabs, most often cut parallel to bedding, face the exterior or interior of many important buildings such as the Parliament Buildings and the Canadian Museum of Civilization in the Ottawa area, the Empress Hotel in Victoria, and the provincial legislatures in Winnipeg and Regina, as well as many commercial buildings especially in the Canadian prairies. At the quarries, the stone is cut vertically, using eight foot (2.44 m) diameter saws mounted on one hundred foot (30.5 m) tracks, then split into 6-8 tonne blocks that are moved using front-end loaders. Gillis Quarries operates a large finishing plant with an area of about 4000 m2. Stone is processed along advanced cutting lines that feature eight primary saws and six gantry saw stations, allowing it to be made into a variety of sizes, shapes, and finishes. The Selkirk Member is 43 m thick and the stone is extracted from a 6-8 m thick interval within the lower part. The upper beds tend to be more buff-coloured than the grey lower beds due to weathering by groundwater. The stone is massive, but extracted blocks are less than ~1m thick due to splitting along stylolites. Consisting of bioturbated wackestone to packstone, the Tyndall Stone was deposited in a shallow-marine environment within the photic zone, in the central part of the vast equatorial epicontinental sea that covered much of Laurentia. Scattered thin, bioclastic grainstone lenses record brief, low-energy storm events. The distinctive mottles are formed by dolomitized

  13. 77 FR 27245 - Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN

    Science.gov (United States)

    2012-05-09

    ... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service [FWS-R3-R-2012-N069; FXRS1265030000S3-123-FF03R06000] Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN AGENCY: Fish and... plan (CCP) and environmental assessment (EA) for Big Stone National Wildlife Refuge (Refuge, NWR) for...

  14. Development and application of new composite grouting material for sealing groundwater inflow and reinforcing wall rock in deep mine.

    Science.gov (United States)

    Jinpeng, Zhang; Limin, Liu; Futao, Zhang; Junzhi, Cao

    2018-04-04

    With cement, bentonite, water glass, J85 accelerator, retarder and water as raw materials, a new composite grouting material used to seal groundwater inflow and reinforce wall rock in deep fractured rock mass was developed in this paper. Based on the reaction mechanism of raw material, the pumpable time, stone rate, initial setting time, plastic strength and unconfined compressive strength of multi-group proportion grouts were tested by orthogonal experiment. Then, the optimum proportion of composite grouting material was selected and applied to the grouting engineering for sealing groundwater inflow and reinforcing wall rock in mine shaft lining. The results show the mixing proportion of the maximum pumpable time, maximum stone rate and minimum initial setting time of grout are A K4 B K1 C K4 D K2 , A K3 B K1 C K1 D K4 and A K3 B K3 C K4 D K1 , respectively. The mixing proportion of the maximum plastic strength and unconfined compressive strength of grouts concretion bodies are A K1 B K1 C K1 D K3 and A K1 B K1 C K1 D K1 , respectively. Balanced the above 5 indicators overall and determined the optimum proportion of grouts: bentonite-cement ratio of 1.0, water-solid ratio of 3.5, accelerator content of 2.9% and retarder content of 1.45%. This new composite grouting material had good effect on the grouting engineering for sealing groundwater inflow and reinforcing wall rock in deep fractured rock mass.

  15. Laser-based assessment of road aggregate particle shape and texture properties with the aim of deriving comparative models

    CSIR Research Space (South Africa)

    Breytenbach, IJ

    2013-10-01

    Full Text Available Research was undertaken using an innovative three-dimensional (3D) laser scanning tool to study the shape and texture characteristics of road aggregate particles. Aggregate materials used for road construction, including G1 crushed rocks...

  16. Measurements of distribution coefficient for Sn, Pb and Th on sand stone and tuff in saline type groundwater

    International Nuclear Information System (INIS)

    Nakazawa, Toshiyuki; Okada, Kenichi; Muroi, Masayuki; Shibata, Masahiro; Sasamoto, Hiroshi

    2004-02-01

    Japan Nuclear Cycle Development Institute (JNC) has developed the sorption database for bentonite and rocks in order to assess the retardation capacities of important radioactive elements in natural and engineered barriers in the H12 report. However, there are not enough distribution coefficient data for radioactive elements in saline type groundwater in the database. Sn (tin), Pb (lead) and Th(thorium) are important radioactive elements for performance assessment of high level radioactive waste disposal, thus we carried out the batch sorption experiments for these radioactive elements on sand stone and tuff. The experiments for each radioactive element were performed on the following conditions; Sn: Kd measurements using the solutions (distilled water or artificial sea water) reacted with sand stone. Pb: Kd measurements using solution (artificial sea water) reacted with sand stone or tuff. Th: Kd measurements using solution (artificial sea water) reacted with sand stone as a function of carbonate concentration. The results of experiment are summarized below; In the case of Sn, Kd were 0.4-1 m 3 /kg in distilled water type and approximately 1 m 3 /kg in artificial sea water type. And also, Kd was 0.3 m 3 /kg in artificial sea water adjusted Ph 12. In artificial sea water type, it was suggested that Kd decreased with pH. In the case of Pb, Kd were approximately 2 m 3 /kg on sand stone and 4-10 m 3 /kg on tuff in artificial sea water type. Kd on tuff was a little larger than that on sand stone. There were no distinctly differences depending on solid-liquid separation methods. In the case of Th, Kd was approximately 1-8 m 3 /kg in artificial sea water type. On the other hand, sorption of Th on sand stone was not observed (i.e., Kd = 0 m 3 /kg) in high carbonate solution. It was estimated that low Kd in high carbonate solution might be caused by speciation of because Th could form the anions in the solution such as hydroxo-carbonate complexes and carbonate complexes

  17. environmental impact of aggregate mining by crush rock industries

    African Journals Online (AJOL)

    2012-07-02

    Jul 2, 2012 ... in form of crushed rock and it is also an essential con- stituent of many ... of production; processing or during extraction. Since .... reserves through deep quarrying. 1.3. ...... Audit Report of Port Harcourt Flour Mill Port Har- court.

  18. Sliding stones of Racetrack Playa, Death Valley, USA: The roles of rock thermal conductivity and fluctuating water levels

    Czech Academy of Sciences Publication Activity Database

    Kletetschka, Günther; Hooke, R. L.; Ryan, A.; Fercana, G.; McKinney, E.; Schwebler, K. P.

    2013-01-01

    Roč. 195, 1 August (2013), s. 110-117 ISSN 0169-555X Institutional support: RVO:67985831 Keywords : Endorheic * Finite element modeling * hydrogeology * Racetrack playa * sliding stones Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.577, year: 2013

  19. Influence of Lithophysal Geometry on the Uniaxial Compression of Tuff-Like Rock

    International Nuclear Information System (INIS)

    Rigby, Douglas B.

    2007-01-01

    A large portion of the rock of the high-level nuclear waste repository at Yucca Mountain contains lithophysae or voids. These voids have a significant detrimental effect on the engineering properties of the rock mass and its performance. The lithophysae were formed at the time of volcanic deposition by pockets of gas trapped within the compressing and cooling pyroclastic flow material. Lithophysae vary by size, shape, and spatial frequency of occurrence. Due to the difficulties of testing actual lithophysal rock, the current mechanical property data set is limited and the numerical models of lithophysal rock are not well validated. The purpose of this task was to experimentally quantify the effect of void geometry in the mechanical compression of cubes of analog lithophysal-like rock. In this research the mechanical properties of the analog rock were systematically studied by examining various patterns of voids based on variables consisting of hole shape, size, and geometrical distribution. Each specified hole pattern was cast into 6 by 6 by 6-in. Hydro-StoneTB(reg s ign) specimens (produced in triplicate) and then tested under uniaxial compression. Solid Hydro-StoneTB(reg s ign) specimens exhibited similar mechanical properties to those estimated for rock mass solid specimens of Topopah Spring tuff. The results indicated that the compressive strength and Young's Modulus values decrease with increasing specimen void porosity. The modulus and strength with void porosity relationships are essentially linear over the 5 to 20 percent void porosity range. When zero void porosity (solid specimen) results are added, exponential functions do not provide a good fit to the data due to a significant sensitivity of strength and modulus to the presence of macro-sized voids. From solid specimens there is roughly a 60 percent drop in strength with about 7 percent void porosity, increasing to an 80 percent drop at about 20 percent void porosity. The percent change in modulus from

  20. Distribution of uranium in the carbonate rock of Um Bogma formation, Southwest, Sinai, Egypt

    International Nuclear Information System (INIS)

    El-AAssy, I.E.; Ahmed, F.Y.; Morsy, A.M.; El-Fawal, F.M.; Mansour, M.Gh.

    1998-01-01

    The lower carboniferous Um bogma Formation is a potential source for Mn, Cu and U. it is mainly composed of dolostone and limestone with few clastic different interbeds of clay stone, siltstone and sandstone. The different diagenetic processes which affected this formation are mainly, compaction, cementation, neomorphism, dissolution, dolomitization, silicification and filling the veins and pores. The distribution of uranium and thorium within the three members and their correlation with the iron oxides and organic matter, were studied. The channel porosity and intercrystalline spaces which resulted from dolomitization acted as pathways for uraniferous solutions in the carbonate rocks. On the other hand, the shales and clay stones underneath the carbonates of Um bogma formation acted as barriers and good depositional environment for the accumulation of uranium on the surfaces of joints and fractures.The accumulated uranium minerals in the carbonate rocks are most likely of the efflorescent deposits

  1. Treatment of gallbladder stone with common bile duct stones in the laparoscopic era.

    Science.gov (United States)

    Zhang, Wei-jie; Xu, Gui-fang; Huang, Qin; Luo, Kun-lun; Dong, Zhi-tao; Li, Jie-ming; Wu, Guo-zhong; Guan, Wen-xian

    2015-01-26

    Laparoscopic common bile duct exploration (LCBDE) for stone can be carried out by either laparoscopic transcystic stone extraction (LTSE) or laparoscopic choledochotomy (LC). It remains unknown as to which approach is optimal for management of gallbladder stone with common bile duct stones (CBDS) in Chinese patients. From May 2000 to February 2009, we prospective treated 346 consecutive patients with gallbladder stones and CBDS with laparoscopic cholecystectomy and LCBDE. Intraoperative findings, postoperative complications, postoperative hospital stay and costs were analyzed. Because of LCBDE failure,16 cases (4.6%) required open surgery. Of 330 successful LCBDE-treated patients, 237 underwent LTSE and 93 required LC. No mortality occurred in either group. The bile duct stone clearance rate was similar in both groups. Patients in the LTSE group were significantly younger and had fewer complications with smaller, fewer stones, shorter operative time and postoperative hospital stays, and lower costs, compared to those in the LC group. Compared with patients with T-tube insertion, patients in the LC group with primary closure had shorter operative time, shorter postoperative hospital stay, and lower costs. In cases requiring LCBDE, LTSE should be the first choice, whereas LC may be restricted to large, multiple stones. LC with primary closure without external drainage of the CBDS is as effective and safe as the T-tube insertion approach.

  2. Everybody Must Get Stones

    Directory of Open Access Journals (Sweden)

    Timothy Darvill

    2009-09-01

    Full Text Available It is now widely recognised that monument building in the fourth and third millennia cal BC often involved transporting selected blocks of preferred stone many kilometres over difficult terrain. Some structures incorporated blocks from several different sources, brought together as an ensemble in much the same way perhaps that assemblages of flint and stone axes reflect both local and distant sources. This article explores alternative models accounting for the selection of stones, contrasting those that foreground symbolic attachments and imposed meanings with those that focus on the intrinsic qualities of particular types of stone and their source. The assemblage of different stone types that accumulated at Stonehenge, Wiltshire, over a period of more than a thousand years is used as a case study.

  3. Conservation of stone built cultural heritage and preservation of memories

    Science.gov (United States)

    Costa, Antônio

    2016-04-01

    Certainly, the main justification for the conservation of cultural heritage built, lies in the meanings that these buildings have, either to the history of nations, either as part of the cultural heritage of humanity. On the other hand, and taking into account the use of stone, it can be said that in addition to cultural and aesthetic values usually associated with these monuments or architectural ensembles that make up this heritage, the presence of stone materials gives another dimension to those constructions, which is the geo-memory. This means that, due to the presence of this material, where each has its own history, it is also possible to identify geo-memories for each of these monuments or architectural ensembles that make up this heritage, either the genesis point of view, involving environments and processes, either regarding the formation ages of these materials. At the same time and due to the use of these materials can be said that each monument or group of monuments is a reflection of the geo-diversity of a determined region or territory. In Brazil, due to its large territory, this geo-diversity includes a wide range of geological environments, phenomena and processes, giving rise to diverse stone materials, which can be observed in the monuments that are part of your built heritage. Thus in old buildings of historic sites located in particular in the southern and southeastern regions of Brazil, this geo-diversity is present because many types of rocks were used, igneous, metamorphic or sedimentary compositions and of very different ages. Of these types stands out, for example, granites and gneisses, which were used in the states of Rio de Janeiro and Minas Gerais, where they are very common. In such cases, the rocks were formed, or end of the Paleoproterozoic, or at the end of the Neoproterozoic and have different textures, sometimes with predominance of biotite, among mica, sometimes amphibole, as hornblende, or with garnet. They were often used in

  4. Use of Local Stone: Successes, Failures and Considerations

    Science.gov (United States)

    Gerns, Edward; Will, Rachel

    2015-04-01

    Stone has been used in construction for thousands of years. Until relatively recently, local stone was used almost exclusively due to limited transportation options and to reduce costs. . Historically, the stone was often taken from nearby fields, known as fieldstone, without any specific quarrying operations and used to create unique assemblages of vernacular buildings. Stone, perhaps more than any other natural building material, has numerous varieties and characteristics within the broader classifications of stone: sedimentary, igneous and metamorphic. In exterior applications, stone historically has been used for foundations, localized cladding elements and in some instances entire building facades. Many of these local stones are appropriate for foundations, but not necessarily for cladding systems, particularly once the stone was quarried and modified rather than used in its natural form. These issues tended to be less significant in historic buildings when wall systems were much thicker and had more redundancies in the cladding systems Since around 1880, the use of these thinner applications of quarried stones as more traditional cladding systems (rather than cladding and structure) has resulted in challenges including unanticipated weathering characteristics, residual stresses and detrimental inclusions. These conditions can result in expensive and extensive repairs and maintenance. Often the options to address these characteristics are limited or potentially drastic depending on the scale of installation. It is important to understand the cause of the issues, understand if these issues are significant and finally how to address them appropriately. Where and how these unique local stones are installed as well as climate and weathering patterns certainly contribute to the potential unanticipated conditions. This presentation will be divided into two general parts. The first will address various stones used historically throughout regions within the United

  5. Using of Stone Flour from Some Mineral Rocks in Modern Concrete

    Science.gov (United States)

    Roman, Moskvin; Elena, Belyakova; Marina, Moroz

    2018-03-01

    There is shown the possibility of using mill ground rocks in SCC without deterioration of rheological properties of concrete mixtures. Obtained high-strength concrete of the new generation with high technical and economic indices and low unit costs per unit of cement strength.

  6. Introduction. Leave no stone unturned: Perspectives on ground stone artefact research

    OpenAIRE

    Danny Rosenberg; Yorke Rowan; Tatjana Gluhak

    2016-01-01

    Ground stone tools served in many physical and social contexts through millennia, reflecting a wide variety of functions. Although ground stone tool studies were neglected for much of early archaeology, the last few decades witnessed a notable international uptick in the way archaeologists confront this multifaceted topic. Today, with the advance of archaeology as a discipline, research into ground stone artefacts is moving into a new phase that integrates high resolution documentation with n...

  7. Extremadura (Spain): a case to be considered as Global Heritage Stone Province

    Science.gov (United States)

    Mota, Maribel; Tejado, Juanjo; Pereira, Dolores

    2015-04-01

    Extremadura is geologically located in the Iberian Massif, belonging part of the Central Iberian Zone, in the north of the region, and the Ossa Morena zone, in the south of it. The Central Iberian Zone is characterized by the abundance of clastic metasedimentary rocks and greywacke, sandstones, shales, conglomerates, quartzites and lesser amounts of carbonate materials such as limestone and dolomite (600-300 Ma). Also featured are Hercynian granitic intrusions. The rocks from the Ossa-Morena zone are metamorphic, intrusive igneous and volcanic (650-300 Ma). Extremadura, given its strategic geographical position, has been the site of human settlement since ancient times, and this civilisation has left its influence on the building materials used in buildings and monuments. The rocks used in building, are directly related to the geology of the immediate area, since rock outcrops, near the construction are mostly granites, slates and marbles. The historic and artistic heritage from Extremadura includes Roman treasures (like the bridges located in the Via de la Plata, dams, walls and milestones), Islamic and Christian treasures as well as medieval and Renaissance Jewish treasures. Extremadura has three World Heritage Sites declared by UNESCO: the old town of Cáceres, the archaeological site at Merida and the monastery of Guadalupe. The latter is built mainly of bricks and masonry. In Merida, granites and diorites of various facies of the batholiths located north of the city are used together with Sierra Carija's marble and quartzite alluvial gravels from the river Guadiana. Among the constructions in Merida, granite utilisation in the theater and amphitheater, aqueduct of Miracles and the Proserpina dam, are remarkable. The old town of Cáceres is characterised by the presence of narrow streets and monuments, medieval churches and Renaissance palaces, built with granite and flanked by a wall constructed during the Muslim period. This granite comes from the quarries

  8. Ultrasonic propulsion of kidney stones.

    Science.gov (United States)

    May, Philip C; Bailey, Michael R; Harper, Jonathan D

    2016-05-01

    Ultrasonic propulsion is a novel technique that uses short bursts of focused ultrasonic pulses to reposition stones transcutaneously within the renal collecting system and ureter. The purpose of this review is to discuss the initial testing of effectiveness and safety, directions for refinement of technique and technology, and opinions on clinical application. Preclinical studies with a range of probes, interfaces, and outputs have demonstrated feasibility and consistent safety of ultrasonic propulsion with room for increased outputs and refinement toward specific applications. Ultrasonic propulsion was used painlessly and without adverse events to reposition stones in 14 of 15 human study participants without restrictions on patient size, stone size, or stone location. The initial feasibility study showed applicability in a range of clinically relevant situations, including facilitating passage of residual fragments following ureteroscopy or shock wave lithotripsy, moving a large stone at the ureteropelvic junction with relief of pain, and differentiating large stones from a collection of small fragments. Ultrasonic propulsion shows promise as an office-based system for transcutaneously repositioning kidney stones. Potential applications include facilitating expulsion of residual fragments following ureteroscopy or shock wave lithotripsy, repositioning stones prior to treatment, and repositioning obstructing ureteropelvic junction stones into the kidney to alleviate acute renal colic.

  9. Sharing refuges on arid islands: ecological and social influence on aggregation behaviour of wall geckos

    Directory of Open Access Journals (Sweden)

    Raquel Vasconcelos

    2017-01-01

    Full Text Available Background The extent of social behaviour among reptiles is underappreciated. Two types of aggregations are recognized in lizards: ecological and social, i.e., related to the attraction to a site or to animals of the same species, respectively. As most lizards are territorial, aggregations increase the probability of aggressive interactions among individuals, a density-dependent behaviour. Methods After some spurious observations of aggregation behaviour in the endemic Cabo Verde nocturnal gecko Tarentola substituta, we conducted a field-based study in order to thoroughly characterize it. We sampled 48 transects and 40 10 × 10 m quadrats on São Vicente Island to describe the incidence, size and composition of aggregations and to study the effect of gecko and refuge density, plus refuge quality, on refuge sharing. We hypothesize that when density of animals and scarcity of high-quality refuges is higher, lizards have increased probability of aggregating. We also predict a consistent pattern of size and composition of groups (male–female pairs, only one adult male per group throughout the year if there is a selected behaviour to avoid agonistic interactions, and low thermal advantage to aggregating individuals. Results We present one of the first evidences of aggregation for Phyllodactylidae geckos. We found that T. substituta forms aggregations around 30–40% of the time, and that refuges are almost always shared by a female-male pair, sometimes with a juvenile, probably a mechanism to avoid aggressive interactions. We also observed that refuge sharing is dependent on refuge quality, as medium–large (thermally more stable and positively selected rocks are shared much more frequently than small ones, but independent of adult sizes. Refuge sharing is also directly related to the density of geckos and inversely related to the density of high-quality refuges. We found no relation between body temperatures of geckos and refuge sharing when

  10. Sharing refuges on arid islands: ecological and social influence on aggregation behaviour of wall geckos.

    Science.gov (United States)

    Vasconcelos, Raquel; Rocha, Sara; Santos, Xavier

    2017-01-01

    The extent of social behaviour among reptiles is underappreciated. Two types of aggregations are recognized in lizards: ecological and social, i.e., related to the attraction to a site or to animals of the same species, respectively. As most lizards are territorial, aggregations increase the probability of aggressive interactions among individuals, a density-dependent behaviour. After some spurious observations of aggregation behaviour in the endemic Cabo Verde nocturnal gecko Tarentola substituta, we conducted a field-based study in order to thoroughly characterize it. We sampled 48 transects and 40 10 × 10 m quadrats on São Vicente Island to describe the incidence, size and composition of aggregations and to study the effect of gecko and refuge density, plus refuge quality, on refuge sharing. We hypothesize that when density of animals and scarcity of high-quality refuges is higher, lizards have increased probability of aggregating. We also predict a consistent pattern of size and composition of groups (male-female pairs, only one adult male per group) throughout the year if there is a selected behaviour to avoid agonistic interactions, and low thermal advantage to aggregating individuals. We present one of the first evidences of aggregation for Phyllodactylidae geckos. We found that T. substituta forms aggregations around 30-40% of the time, and that refuges are almost always shared by a female-male pair, sometimes with a juvenile, probably a mechanism to avoid aggressive interactions. We also observed that refuge sharing is dependent on refuge quality, as medium-large (thermally more stable and positively selected) rocks are shared much more frequently than small ones, but independent of adult sizes. Refuge sharing is also directly related to the density of geckos and inversely related to the density of high-quality refuges. We found no relation between body temperatures of geckos and refuge sharing when controlling the effect of rock/air temperature

  11. Influence of Pelvicaliceal Anatomy on Stone Clearance After Flexible Ureteroscopy and Holmium Laser Lithotripsy for Large Renal Stones.

    Science.gov (United States)

    Inoue, Takaaki; Murota, Takashi; Okada, Shinsuke; Hamamoto, Shuzo; Muguruma, Kouei; Kinoshita, Hidefumi; Matsuda, Tadashi

    2015-09-01

    This study was performed to evaluate the impact of pelvicaliceal anatomy on stone clearance in patients with remnant fragments in the lower pole after flexible ureteroscopy and holmium laser lithotripsy (fURSL) for renal stones >15 mm. This retrospective study included 67 patients with radiopaque residual fragments (>2 mm) in the lower pole after fURSL for large renal stones (>15 mm). The preoperative infundibular length (IL), infundibular width (IW), infundibulopelvic angle (IPA), and caliceal pelvic height (CPH) were measured using intravenous urography. Multivariate analysis was performed to determine whether any of these measurements affected stone clearance. Of the 67 patients, 55 (82.1%) were stone free (SF) 3 months after fURSL. The anatomic factors significantly favorable for an SF status were a short IL, broad IW, wide IPA, and low CPH. On multivariate analysis, the IPA had a significant influence on an SF status after fURSL (p=0.010). An IPA renal stones according to our multivariate analysis. Additional studies are required to further evaluate the characteristics of the pelvicaliceal anatomy influencing stone clearance.

  12. Stone Carving in The Locality 0f Eskişehir With its Natural and Cultural Properties: Meerschaum

    Directory of Open Access Journals (Sweden)

    Nurbiye UZ

    2013-06-01

    Full Text Available Also known as sepiolite, meerschaum is a rock with magnesium and silicium base. This stone is whitish in color, with a very thin texture. Although known to be mostly used for making pipes, the archeological researches about this stone revealed that it had been known for about 5000 years and had been used for various purposes. Today it is seen to be used as a filtering and insulation material thanks to its absorbent property, whereas it has another use in knickknack making with its easily carved texture. Meerschaum is found in countries such as Somali, Czech Republic, United States of America, Greece, Spain, and France in the world, and around the city of Eskişehir in our country. Almost all of the free-milling deposits of this stone is in Turkey, quarrying of which is rather hard. Meerschaum carving, as a craft identified with Eskişehir, is a challenging artisanship that requires mastery, experience, skill, and patience. Although the sizes and durability are not very attractive for the artists, it is possible to see examples of sculpture made of meerschaum. 

  13. Impact of bearing plates dimensions on interaction of mine workings support and rock mass

    Directory of Open Access Journals (Sweden)

    Marek Rotkegel

    2015-01-01

    Full Text Available The aim of the research presented in this article is to assess the impact of bearing plates dimensions on the interaction of steel arch support and rock mass. The analysis of the bearing plates was based on laboratory tests and numerical calculations using the FLAC3D program (a finite difference method and the strain-hardening/softening model based on prescribed variations of Mohr–Coulomb properties. The article presents the results of laboratory tests on selected bearing plates and the results of numerical analysis of the interaction between the bearing plates and rock mass with coal, clay stone and sandstone properties.

  14. Study on Plastic Coated Overburnt Brick Aggregate as an Alternative Material for Bituminous Road Construction

    Directory of Open Access Journals (Sweden)

    Dipankar Sarkar

    2016-01-01

    Full Text Available There are different places in India where natural stone aggregates are not available for constructional work. Plastic coated OBBA can solve the problem of shortage of stone aggregate to some extent. The engineers are always encouraged to use locally available materials. The present investigation is carried out to evaluate the plastic coated OBBA as an alternative material for bituminous road construction. Shredded waste plastics are mixed with OBBA in different percentages as 0.38, 0.42, 0.46, 0.50, 0.54, and 0.60 of the weight of brick aggregates. Marshall Method of mix design is carried out to find the optimum bitumen content of such bituminous concrete mix prepared by plastic coated OBBA. Bulk density, Marshall Stability, flow, Marshall Quotient, ITS, TSR, stripping, fatigue life, and deformations have been determined accordingly. Marshall Stability value of 0.54 percent of plastic mix is comparatively higher than the other mixes except 0.60 percent of plastic mix. Test results are within the prescribed limit for 0.54 percent of plastic mix. There is a significant reduction in rutting characteristics of the same plastic mix. The fatigue life of the mix is also significantly higher. Thus plastic coated OBBA is found suitable in construction of bituminous concrete road.

  15. SHAPE ANALYSIS OF FINE AGGREGATES USED FOR CONCRETE

    Directory of Open Access Journals (Sweden)

    Huan He

    2016-12-01

    Full Text Available Fine aggregate is one of the essential components in concrete and significantly influences the material properties. As parts of natures, physical characteristics of fine aggregate are highly relevant to its behaviors in concrete. The most of previous studies are mainly focused on the physical properties of coarse aggregate due to the equipment limitations. In this paper, two typical fine aggregates, i.e. river sand and crushed rock, are selected for shape characterization. The new developed digital image analysis systems are employed as the main approaches for the purpose. Some other technical methods, e.g. sieve test, laser diffraction method are also used for the comparable references. Shape characteristics of fine aggregates with different origins but in similar size ranges are revealed by this study. Compared with coarse aggregate, fine grains of different origins generally have similar shape differences. These differences are more significant in surface texture properties, which can be easily identified by an advanced shape parameter: bluntness. The new image analysis method is then approved to be efficient for the shape characterization of fine aggregate in concrete.

  16. Transportation and utilization of aggregates for road construction

    Science.gov (United States)

    Fladvad, Marit; Wigum, Børge Johannes; Aurstad, Joralf

    2017-04-01

    Road construction relies on non-renewable aggregate resources as the main construction material. Sources for high-quality aggregate resources are scattered, and requirements for aggregate quality can cause long transport distances between quarry and road construction site. In European countries, the average aggregate consumption per capita is 5 tonnes per year (European Aggregates Association, 2016), while the corresponding figure for Norway is 11 tonnes (Neeb, 2015). Half the Norwegian aggregate production (sand, gravel and crushed rock) is used for road construction. In Norway, aggregate resources have been considered abundant. However, stricter requirement for aggregate quality, and increased concern for sustainability and environmental issues have spurred focus on reduction of transport lengths through better utilization of local aggregate materials. In this research project, information about pavement design and aggregate quality requirements were gathered from a questionnaire sent to selected experts from the World Road Organization (PIARC), European Committee for Standardization (CEN), and Nordic Road Association (NVF). The gathered data was compared to identify differences and similarities for aggregate use in the participating countries. Further, the data was compared to known data from Norway regarding: - amount of aggregates required for a road structure - aggregate transport lengths and related costs A total of 18 countries participated in the survey, represented by either road authorities, research institutions, or contractors. There are large variations in practice for aggregate use among the represented countries, and the selection of countries is sufficient to illustrate a variety in pavement designs, aggregate sizes, and quality requirements for road construction. There are considerable differences in both pavement thickness and aggregate sizes used in the studied countries. Total thicknesses for pavement structures varies from 220 mm to 2400 mm

  17. Production and characterization of composite stone

    International Nuclear Information System (INIS)

    Leirose, G.D.; Lameiras, F.S.

    2012-01-01

    Composite stone is a product similar to natural granite or marble, produced with particles of these materials. This material is used like natural stone as lining. The fabrication of artificial stones using residues of banded iron formations is a promising alternative to its actual destination (storage in dam). This research aims the characterization of composite stone to prove the efficacy of this kind of processing. It was used first, natural quartz as a raw material. The patterns of the samples were confirmed by IR spectra and XRD patterns, ensuring the reproducibility of processing applied. Moreover, this material is homogeneous, with low porosity and high flexural strength, confirmed by its structural characterization. Thus, it can be affirmed that the process chosen is suitable, enabling the application of this methodology to the use of waste. (author)

  18. Co-melting technology in resource recycling of sludge derived from stone processing.

    Science.gov (United States)

    Hu, Shao-Hua; Hu, Shen-Chih; Fu, Yen-Pei

    2012-12-01

    Stone processing sludge (SPS) is a by-product of stone-processing wastewater treatment; it is suitable for use as a raw material for making artificial lightweight aggregates (ALWAs). In this study, boric acid was utilized as a flux to lower sintering temperature. The formation of the viscous glassy phase was observed by DTA curve and changes in XRD patterns. Experiments were conducted to find the optimal combination of sintering temperature, sintering time, and boric acid dosage to produce an ALWA of favorable characteristics in terms of water absorption, bulk density, apparent porosity, compressive strength and weight loss to satisfy Taiwan's regulatory requirements for construction and insulation materials. Optimal results gave a sintering temperature of 850 degrees C for 15 min at a boric acid dosage of 15% by weight of SPS. Results for ALWA favorable characteristics were: 0.21% (water absorption), 0.35% (apparent porosity), 1.67 g/cm3 (bulk density), 66.94 MPa (compressive strength), and less than 0.1% (weight loss).

  19. Concrete with onyx waste aggregate as aesthetically valued structural concrete

    Science.gov (United States)

    Setyowati E., W.; Soehardjono, A.; Wisnumurti

    2017-09-01

    The utillization of Tulungagung onyx stone waste as an aggregate of concrete mixture will improve the economic value of the concrete due to the brighter color and high aesthetic level of the products. We conducted the research of 75 samples as a test objects to measure the compression stress, splits tensile stress, flexural tensile stress, elasticity modulus, porosity modulus and also studied 15 test objects to identify the concrete micro structures using XRD test, EDAX test and SEM test. The test objects were made from mix designed concrete, having ratio cement : fine aggregate : coarse aggregate ratio = 1 : 1.5 : 2.1, and W/C ratio = 0.4. The 28 days examination results showed that the micro structure of Tulungagung onyx waste concrete is similar with normal concrete. Moreover, the mechanical test results proved that Tulungagung onyx waste concretes also have a qualified level of strength to be used as a structural concrete with higher aesthetic level.

  20. Quality Assessment of Urinary Stone Analysis

    DEFF Research Database (Denmark)

    Siener, Roswitha; Buchholz, Noor; Daudon, Michel

    2016-01-01

    After stone removal, accurate analysis of urinary stone composition is the most crucial laboratory diagnostic procedure for the treatment and recurrence prevention in the stone-forming patient. The most common techniques for routine analysis of stones are infrared spectroscopy, X-ray diffraction......, fulfilled the quality requirements. According to the current standard, chemical analysis is considered to be insufficient for stone analysis, whereas infrared spectroscopy or X-ray diffraction is mandatory. However, the poor results of infrared spectroscopy highlight the importance of equipment, reference...... spectra and qualification of the staff for an accurate analysis of stone composition. Regular quality control is essential in carrying out routine stone analysis....

  1. Significance of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy in nonobstructive isolated renal pelvic stones.

    Science.gov (United States)

    Sozen, Sinan; Kupeli, Bora; Acar, Cenk; Gurocak, Serhat; Karaoglan, Ustunol; Bozkirli, Ibrahim

    2008-05-01

    To investigate the probable effect of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy (SWL) in patients with nonobstructive renal pelvic stones. The clinical records of patients with isolated renal pelvic stones who underwent SWL between 1996 and 2005 were reviewed. After excluding patients with obstruction leading to dilatation, major anatomic abnormalities, noncalcium stones, metabolic abnormalities, history of recurrent stone disease, multiple stones, and previous renal surgery, 153 patients were enrolled in the study. Lower pole infundibulopelvic angle (IPA) and infundibular length and width were measured from intravenous urography. Patients were classified into three groups according to stone burden (group 1, renal pelvis, and both in 50 (32.6%), 29 (18.9%), and 8 (5.2%) patients, respectively. There was no statistically significant difference in pelvicaliceal anatomic features except narrower IPA (P=0.02) in group 1 patients with residual stones. The falling of stone fragments to the lower calix in spite of the ureter whether clinically significant or not after SWL of pelvic stones initially seems to be related to stone burden rather than lower caliceal anatomy. However, existence of a more narrow IPA in group 1 patients with residual fragments led us to believe that lower-pole IPA can play a role in stone clearance, especially for smaller stones, probably because of smaller residual fragment size or the more mobile nature of the primary stone.

  2. Rock-fall Hazard In The Yosemite Valley, California

    Science.gov (United States)

    Guzzetti, F.; Reichenbach, P.; Wieczorek, G. F.

    Rock slides and rock falls are the most frequent slope movements in Yosemite Na- tional Park, California. In historical time (1851-2001), more than 400 rock falls and rock slides have been documented in the valley, and some of them have been mapped in detail. We present the preliminary results of an attempt to assess rockfall hazard in the Yosemite Valley using STONE, a 3-dimensional rock-fall simulation computer program. The software computes 3-dimensional rock-fall trajectories starting from a digital terrain model (DTM), the location of rock-fall release points (source areas), and maps of the dynamic rolling coefficient and of the coefficients of normal and tan- gential energy restitution. For each DTM cell the software also calculates the number of rock falls passing through the cell, the maximum rock-fall velocity and the maxi- mum flying height. For the Yosemite Valley, a DTM with a ground resolution of 10 x 10 m was prepared using topographic contour lines from USGS 1:24,000-scale maps. Rock-fall release points were identified as DTM cells having a slope steeper than 60 degrees, an assumption based on the location of historical rock falls. Maps of the nor- mal and tangential energy restitution coefficients and of the rolling friction coefficient were produced from a surficial geologic map. The availability of historical rock falls mapped in detail allowed us to check the computer program performance and to cali- brate the model parameters. Visual and statistical comparison of the model results with the mapped rock falls confirmed the accuracy of the model. The model results are also compared with a geomorphic assessment of rock-fall hazard based on potential energy referred to as a "shadow angle" approach, recently completed for the Yosemite Valley.

  3. Kidney Stones in Children and Teens

    Science.gov (United States)

    ... Issues Listen Español Text Size Email Print Share Kidney Stones in Children and Teens Page Content Article ... teen girls having the highest incidence. Types of Kidney Stones There are many different types of kidney ...

  4. Famous Stone Patients and Their Disease

    Science.gov (United States)

    Moran, Michael E.

    2007-04-01

    The fact that stone patients have endured much throughout the ages and that prior to our current era, when the ultimate horror, "being cut for the stone" was the only alternative to the repeated episodes of colic, should be recalled from time to time. Urolithiasis has affected humanity throughout the ages and has been indiscriminate to those lives it touched. A full accounting of those who have suffered and recorded their agonies is beyond the scope of this investigation; however, even a partial accounting is valuable for present day physicians who care for those with stone disease. For the present work, the historical accounts of stone disease literature were scrutinized for individual sufferers who could be cross-referenced from other sources as legitimately afflicted by stones. Only those patients that could be documented and were (or are) well known were included, because the internet is now a verdant repository of thousands of "not so well knowns." Reliable historical data was found for a variety of persons from the pre-Christian era to the present, including those remembered as philosophers and scientists, physicians, clergy, leaders and rulers, entertainers, athletes and fictitious/Hollywood-type individuals. Verified accounts of famous stone formers were chosen for this paper, and are presented in chronological order. The list of urolithiasis sufferers presented here is undoubtedly incomplete, but it is not through lack of trying that they are missing. Most often, the suffering do so silently, and that is always allowed.

  5. Still Bay Point-Production Strategies at Hollow Rock Shelter and Umhlatuzana Rock Shelter and Knowledge-Transfer Systems in Southern Africa at about 80-70 Thousand Years Ago

    Science.gov (United States)

    Lombard, Marlize

    2016-01-01

    It has been suggested that technological variations associated with Still Bay assemblages of southern Africa have not been addressed adequately. Here we present a study developed to explore regional and temporal variations in Still Bay point-production strategies. We applied our approach in a regional context to compare the Still Bay point assemblages from Hollow Rock Shelter (Western Cape) and Umhlatuzana Rock Shelter (KwaZulu-Natal). Our interpretation of the point-production strategies implies inter-regional point-production conventions, but also highlights variability and intra-regional knapping strategies used for the production of Still Bay points. These strategies probably reflect flexibility in the organisation of knowledge-transfer systems at work during the later stages of the Middle Stone Age between about 80 ka and 70 ka in South Africa. PMID:27942012

  6. Deteriorating effects of lichen and microbial colonization of carbonate building rocks in the Romanesque churches of Segovia (Spain)

    International Nuclear Information System (INIS)

    Rios, Asuncion de los; Camara, Beatriz; Garcia del Cura, Ma Angeles; Rico, Victor J.; Galvan, Virginia; Ascaso, Carmen

    2009-01-01

    In this study, the deterioration effects of lichens and other lithobionts in a temperate mesothermal climate were explored. We examined samples of dolostone and limestone rocks with visible signs of biodeterioration taken from the exterior wall surfaces of four Romanesque churches in Segovia (Spain): San Lorenzo, San Martin, San Millan and La Vera Cruz. Biofilms developing on the lithic substrate were analyzed by scanning electron microscopy. The most common lichen species found in the samples were recorded. Fungal cultures were then obtained from these carbonate rocks and characterized by sequencing Internal Transcribed Spacers (ITS). Through scanning electron microscopy in back-scattered electron mode, fungi (lichenized and non-lichenized) were observed as the most frequent microorganisms occurring at sites showing signs of biodeterioration. The colonization process was especially conditioned by the porosity characteristics of the stone used in these buildings. While in dolostones, microorganisms mainly occupied spaces comprising the rock's intercrystalline porosity, in bioclastic dolomitized limestones, fungal colonization seemed to be more associated with moldic porosity. Microbial biofilms make close contact with the substrate, and thus probably cause significant deterioration of the underlying materials. We describe the different processes of stone alteration induced by fungal colonization and discuss the implications of these processes for the design of treatments to prevent biodeterioration

  7. Deteriorating effects of lichen and microbial colonization of carbonate building rocks in the Romanesque churches of Segovia (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Rios, Asuncion de los [Instituto de Recursos Naturales, Centro de Ciencias Medioambientales (CSIC), Serrano 115 dpdo., 28006 Madrid (Spain)], E-mail: arios@ccma.csic.es; Camara, Beatriz [Instituto de Recursos Naturales, Centro de Ciencias Medioambientales (CSIC), Serrano 115 dpdo., 28006 Madrid (Spain); Garcia del Cura, Ma Angeles [Instituto de Geologia Economica CSIC-UCM, Laboratorio de Petrologia Aplicada, Unidad Asociada CSIC-UA, Alicante (Spain); Rico, Victor J. [Departamento de Biologia Vegetal II, Facultad de Farmacia, Universidad Complutense, 28040 Madrid (Spain); Galvan, Virginia [Facultad Patrimonio Cultural, Universidad SEK, Convento de Santa Cruz la Real, 40003 Segovia (Spain); Ascaso, Carmen [Instituto de Recursos Naturales, Centro de Ciencias Medioambientales (CSIC), Serrano 115 dpdo., 28006 Madrid (Spain)

    2009-01-15

    In this study, the deterioration effects of lichens and other lithobionts in a temperate mesothermal climate were explored. We examined samples of dolostone and limestone rocks with visible signs of biodeterioration taken from the exterior wall surfaces of four Romanesque churches in Segovia (Spain): San Lorenzo, San Martin, San Millan and La Vera Cruz. Biofilms developing on the lithic substrate were analyzed by scanning electron microscopy. The most common lichen species found in the samples were recorded. Fungal cultures were then obtained from these carbonate rocks and characterized by sequencing Internal Transcribed Spacers (ITS). Through scanning electron microscopy in back-scattered electron mode, fungi (lichenized and non-lichenized) were observed as the most frequent microorganisms occurring at sites showing signs of biodeterioration. The colonization process was especially conditioned by the porosity characteristics of the stone used in these buildings. While in dolostones, microorganisms mainly occupied spaces comprising the rock's intercrystalline porosity, in bioclastic dolomitized limestones, fungal colonization seemed to be more associated with moldic porosity. Microbial biofilms make close contact with the substrate, and thus probably cause significant deterioration of the underlying materials. We describe the different processes of stone alteration induced by fungal colonization and discuss the implications of these processes for the design of treatments to prevent biodeterioration.

  8. Assessment and Calibration of Ultrasonic Measurement Errors in Estimating Weathering Index of Stone Cultural Heritage

    Science.gov (United States)

    Lee, Y.; Keehm, Y.

    2011-12-01

    Estimating the degree of weathering in stone cultural heritage, such as pagodas and statues is very important to plan conservation and restoration. The ultrasonic measurement is one of commonly-used techniques to evaluate weathering index of stone cultual properties, since it is easy to use and non-destructive. Typically we use a portable ultrasonic device, PUNDIT with exponential sensors. However, there are many factors to cause errors in measurements such as operators, sensor layouts or measurement directions. In this study, we carried out variety of measurements with different operators (male and female), different sensor layouts (direct and indirect), and sensor directions (anisotropy). For operators bias, we found that there were not significant differences by the operator's sex, while the pressure an operator exerts can create larger error in measurements. Calibrating with a standard sample for each operator is very essential in this case. For the sensor layout, we found that the indirect measurement (commonly used for cultural properties, since the direct measurement is difficult in most cases) gives lower velocity than the real one. We found that the correction coefficient is slightly different for different types of rocks: 1.50 for granite and sandstone and 1.46 for marble. From the sensor directions, we found that many rocks have slight anisotropy in their ultrasonic velocity measurement, though they are considered isotropic in macroscopic scale. Thus averaging four different directional measurement (0°, 45°, 90°, 135°) gives much less errors in measurements (the variance is 2-3 times smaller). In conclusion, we reported the error in ultrasonic meaurement of stone cultural properties by various sources quantitatively and suggested the amount of correction and procedures to calibrate the measurements. Acknowledgement: This study, which forms a part of the project, has been achieved with the support of national R&D project, which has been hosted by

  9. ALKALI AGGREGATE REACTIONS IN CONCRETE: A REVIEW OF ...

    African Journals Online (AJOL)

    coarse aggregate, water and chemical admixtures to improve its various .... slowly from certai~ alkali-bearing rock components within the ... retaining walls. ... expand in pores and microcracks of the cementious matrix. ... allY'a' pressure on the surrounding concrete ... effect is reduced structural integrity and shortened.

  10. Thallium and its contents in Remata carbonate rocks

    Directory of Open Access Journals (Sweden)

    Kondelová Marcela

    1996-09-01

    Full Text Available The article presents at first the list of thallium own minerals and its isomorphic content in other minerals, especially in Slovakian ore deposits. This trace element was found in numerous dolomite-rock samples from Remata massif near Handlová. An interesting level of Tl content was analyzed in nonsilicified rocks; the highest content of Tl (and Ag are along the E – W line of disturbance. The presence of thallium in some limonitic aggregates in close Kremnica-gold deposit indicate any continuous relation. Some similarities to type gold deposits Carlin ( USA are discussed, even if no gold and discrete thallium phases were in Remata determined yet.

  11. Endoscopic Stone Measurement During Ureteroscopy.

    Science.gov (United States)

    Ludwig, Wesley W; Lim, Sunghwan; Stoianovici, Dan; Matlaga, Brian R

    2018-01-01

    Currently, stone size cannot be accurately measured while performing flexible ureteroscopy (URS). We developed novel software for ureteroscopic, stone size measurement, and then evaluated its performance. A novel application capable of measuring stone fragment size, based on the known distance of the basket tip in the ureteroscope's visual field, was designed and calibrated in a laboratory setting. Complete URS procedures were recorded and 30 stone fragments were extracted and measured using digital calipers. The novel software program was applied to the recorded URS footage to obtain ureteroscope-derived stone size measurements. These ureteroscope-derived measurements were then compared with the actual-measured fragment size. The median longitudinal and transversal errors were 0.14 mm (95% confidence interval [CI] 0.1, 0.18) and 0.09 mm (95% CI 0.02, 0.15), respectively. The overall software accuracy and precision were 0.17 and 0.15 mm, respectively. The longitudinal and transversal measurements obtained by the software and digital calipers were highly correlated (r = 0.97 and 0.93). Neither stone size nor stone type was correlated with error measurements. This novel method and software reliably measured stone fragment size during URS. The software ultimately has the potential to make URS safer and more efficient.

  12. 78 FR 3911 - Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN; Final Comprehensive...

    Science.gov (United States)

    2013-01-17

    ... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service [FWS-R3-R-2012-N259; FXRS1265030000-134-FF03R06000] Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN; Final Comprehensive... significant impact (FONSI) for the environmental assessment (EA) for Big Stone National Wildlife Refuge...

  13. Poisson's Ratio and Auxetic Properties of Natural Rocks

    Science.gov (United States)

    Ji, Shaocheng; Li, Le; Motra, Hem Bahadur; Wuttke, Frank; Sun, Shengsi; Michibayashi, Katsuyoshi; Salisbury, Matthew H.

    2018-02-01

    Here we provide an appraisal of the Poisson's ratios (υ) for natural elements, common oxides, silicate minerals, and rocks with the purpose of searching for naturally auxetic materials. The Poisson's ratios of equivalently isotropic polycrystalline aggregates were calculated from dynamically measured elastic properties. Alpha-cristobalite is currently the only known naturally occurring mineral that has exclusively negative υ values at 20-1,500°C. Quartz and potentially berlinite (AlPO4) display auxetic behavior in the vicinity of their α-β structure transition. None of the crystalline igneous and metamorphic rocks (e.g., amphibolite, gabbro, granite, peridotite, and schist) display auxetic behavior at pressures of >5 MPa and room temperature. Our experimental measurements showed that quartz-rich sedimentary rocks (i.e., sandstone and siltstone) are most likely to be the only rocks with negative Poisson's ratios at low confining pressures (≤200 MPa) because their main constituent mineral, α-quartz, already has extremely low Poisson's ratio (υ = 0.08) and they contain microcracks, micropores, and secondary minerals. This finding may provide a new explanation for formation of dome-and-basin structures in quartz-rich sedimentary rocks in response to a horizontal compressional stress in the upper crust.

  14. Retroperitoneoscopy for treatment of renal and ureteral stones

    Directory of Open Access Journals (Sweden)

    Rodrigo S. Soares

    2005-04-01

    Full Text Available OBJECTIVE: To assess the efficacy of retroperitoneoscopy for treating stones in the renal pelvis and proximal ureter. MATERIALS AND METHODS: In the period from August 2003 to August 2004, 35 retroperitoneoscopies for treatment of urinary stones were performed on 34 patients. Fifteen patients (42% had stones in the renal pelvis, and in 2 cases, there were associated stones in the upper caliceal group. Twenty patients (58% had ureteral stones, all of them located above the iliac vessel. Twenty-five patients (71% had previously undergone at least one session of extracorporeal lithotripsy and 8 patients (26% also underwent ureteroscopy to attempt to remove the stone. Eight patients underwent retroperitoneoscopy as a primary procedure. Stone size ranged from 0.5 to 6 cm with a mean of 2.1 cm. RESULTS: Retroperitoneoscopy was performed by lumbar approach with initial access conducted by open technique and creation of space by digital dissection. We used a 10-mm Hasson trocar for the optics, and 2 or 3 additional working ports placed under visualization. Following identification, the urinary tract was opened with a laparoscopic scalpel and the stone was removed intact. The urinary tract was closed with absorbable 4-0 suture and a Penrose drain was left in the retroperitoneum. In 17 patients (49%, a double-J stent was maintained postoperatively. Surgical time ranged from 60 to 260 minutes with a mean of 140 minutes. The mean hospital stay was 3 days (1-10 days. The mean length of retroperitoneal urinary drainage was 3 days (1-10 days. There were minor complications in 6 (17.6% patients and 1 case of conversion due to technical difficulty. Thirty-three patients (94% became stone free. CONCLUSION: Retroperitoneoscopy is an effective, low-morbidity alternative for treatment of urinary stones.

  15. Retroperitoneoscopy for treatment of renal and ureteral stones.

    Science.gov (United States)

    Soares, Rodrigo S; Romanelli, Pedro; Sandoval, Marcos A; Salim, Marcelo M; Tavora, Jose E; Abelha, David L

    2005-01-01

    To assess the efficacy of retroperitoneoscopy for treating stones in the renal pelvis and proximal ureter. In the period from August 2003 to August 2004, 35 retroperitoneoscopies for treatment of urinary stones were performed on 34 patients. Fifteen patients (42%) had stones in the renal pelvis, and in 2 cases, there were associated stones in the upper caliceal group. Twenty patients (58%) had ureteral stones, all of them located above the iliac vessel. Twenty-five patients (71%) had previously undergone at least one session of extracorporeal lithotripsy and 8 patients (26%) also underwent ureteroscopy to attempt to remove the stone. Eight patients underwent retroperitoneoscopy as a primary procedure. Stone size ranged from 0.5 to 6 cm with a mean of 2.1 cm. Retroperitoneoscopy was performed by lumbar approach with initial access conducted by open technique and creation of space by digital dissection. We used a 10-mm Hasson trocar for the optics, and 2 or 3 additional working ports placed under visualization. Following identification, the urinary tract was opened with a laparoscopic scalpel and the stone was removed intact. The urinary tract was closed with absorbable 4-0 suture and a Penrose drain was left in the retroperitoneum. In 17 patients (49%), a double-J stent was maintained postoperatively. Surgical time ranged from 60 to 260 minutes with a mean of 140 minutes. The mean hospital stay was 3 days (1-10 days). The mean length of retroperitoneal urinary drainage was 3 days (1-10 days). There were minor complications in 6 (17.6%) patients and 1 case of conversion due to technical difficulty. Thirty-three patients (94%) became stone free. Retroperitoneoscopy is an effective, low-morbidity alternative for treatment of urinary stones.

  16. Stability of submerged rock berms exposed to motion of liquefied soil in waves

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Dixen, Figen Hatipoglu; Fredsøe, Jørgen

    2011-01-01

    . Various berm materials were used, stones of size 0.74–2.5cm, plastic balls of size 3.6cm, brass of size 2.5cm and steel of size 1.0cm. The experiments show that rock berms that are stable under very large waves can be unstable when they are exposed to the motion of liquefied soil. The limited data......The paper describes the results of an experimental study on the behaviour of a submerged rock berm in liquefied backfill soil. The soil is liquefied by waves, and the rock berm is subject to the orbital motion of the liquefied soil. The soil used in the experiments was silt with d50=0.075mm...

  17. Middle Stone Age bedding construction and settlement patterns at Sibudu, South Africa.

    Science.gov (United States)

    Wadley, Lyn; Sievers, Christine; Bamford, Marion; Goldberg, Paul; Berna, Francesco; Miller, Christopher

    2011-12-09

    The Middle Stone Age (MSA) is associated with early behavioral innovations, expansions of modern humans within and out of Africa, and occasional population bottlenecks. Several innovations in the MSA are seen in an archaeological sequence in the rock shelter Sibudu (South Africa). At ~77,000 years ago, people constructed plant bedding from sedges and other monocotyledons topped with aromatic leaves containing insecticidal and larvicidal chemicals. Beginning at ~73,000 years ago, bedding was burned, presumably for site maintenance. By ~58,000 years ago, bedding construction, burning, and other forms of site use and maintenance intensified, suggesting that settlement strategies changed. Behavioral differences between ~77,000 and 58,000 years ago may coincide with population fluctuations in Africa.

  18. Excavated rock materials from tunnels for sprayed concrete

    OpenAIRE

    Luong, Judy Yuen Wah; Aarstad, Kari; De Weerdt, Klaartje; Bjøntegaard, Øyvind

    2017-01-01

    Sand extracted from natural resources is widely used in concrete production nowadays. The increase in demand for concrete production has resulted in shortage of natural sand resources, especially in terms of suitable materials for concrete production. At the same time, large amounts of excavated rock materials are and have been generated from tunnelling projects and discarded. Hence, there is an opportunity to use these excavated rock materials as aggregates for concrete production. The chall...

  19. COMORBIDITY OF KIDNEY STONES AND PYCHIATRIC DISEASE

    OpenAIRE

    Bilić, Vedran; Marčinko, Darko

    2010-01-01

    This paper describes a patient who is suffering from PTSD with elements of hypochondria, panic attacks and episodes of 0depression in comorbidity with kidney stones. Kidney stones provoked egzacerbation of psychiatric symptoms. Kidney stones and frustration about them have taken part of provoking factor, the last drop, which led to regression of otherwise precarious, but compensated patient’s mental functioning which resulted in development of psychiatric symptoms.

  20. Histopathology Predicts the Mechanism of Stone Formation

    Science.gov (United States)

    Evan, Andrew P.

    2007-04-01

    About 5% of American women and 12% of men will develop a kidney stone at some time in their life and these numbers appear to be on the rise. Despite years of scientific research into the mechanisms of stone formation and growth, limited advances have been made until recently. Randall's original observations and thoughts on the mechanisms for kidney stone formation have been validated for idiopathic calcium oxalate stone formers (ICSF) but not for most other stone forming groups. Our current studies on selected groups of human stone formers using intraoperative papillary biopsies has shown overwhelming evidence for the presence of Randall's plaque in ICSF and that stone formation and growth are exclusively linked to its availability to urinary ions and proteins. Intense investigation of the plaque-stone junction is needed if we are to understand the factors leading to the overgrowth process on exposed regions of plaque. Such information should allow the development of treatment strategies to block stone formation in ICSF patients. Patients who form brushite stones, or who form apatite stones because of distal renal tubular acidosis (dRTA), or patients with calcium oxalate stones due to obesity bypass procedures, or patients with cystinuria, get plugged inner medullary collecting ducts (IMCD) which leads to total destruction of the lining cells and focal sites of interstitial fibrosis. These stone formers have plaque but at levels equal to or below non-stone formers, which would suggest that they form stones by a different mechanism than do ICSF patients.

  1. Obesometric factors associated with increased skin-to-stone distances in renal stone patients.

    Science.gov (United States)

    Allard, Christopher B; Shuster, Anatoly; Pinthus, Jehonathan H; Farrokhyar, Forough; Raees, A; Patlas, Michael; Matsumoto, Edward D; Whelan, J Paul

    2012-12-01

    Obese patients are at increased risk for renal stones as well as treatment failures due to increased skin-to-stone distances (SSD) and harder stone compositions. We investigated the relationships between obesometric parameters (body mass index [BMI], body fat distribution and obesity-related hormone levels) with SSD and stone hardness. We prospectively enrolled patients undergoing stone interventions at our institution. Computed tomography (CT) scans were analyzed; adipose tissue was identified according to Hounsfield units (HU) and separated into subcutaneous (SAT) and visceral (VAT) components. The pixels were averaged at three levels to calculate fat distribution: %VAT = (VAT)/(VAT + SAT). SSD was measured and HU were used as a surrogate for stone hardness. Obesity-related hormones leptin and adiponectin were measured by ELISA. Seventy-nine patients were prospectively enrolled. Mean BMI and %VAT were 30.02 kg/m2 and 40.13 kg/m2. Mean leptin and adiponectin levels were 17.5 ng/mL and 7.67 mcg/mL indicating high risk for metabolic consequences of obesity. Females had greater proportions of subcutaneous fat than males (%VAT 28.4 versus 46.94, p r = 0.454, p = 0.008). Obese patients with %VAT > 40 versus stone compositions as measured by HU than non-diabetics (982.86 versus 648.86, p = 0.001). Obesometric parameters such as BMI, body fat distribution, and the presence of diabetes mellitus are important considerations in the management of renal stone disease. A large proportion of subcutaneous fat, which can be estimated by physical examination, predicts SSD among obese patients and may aid treatment decisions in patients, particularly those without pre-treatment CT scans. Further studies are needed to refine the role of obesometrics in personalizing treatment decisions.

  2. Comparison of STONE, CROES and Guy's nephrolithometry scoring systems for predicting stone-free status and complication rates after percutaneous nephrolithotomy in obese patients.

    Science.gov (United States)

    Ozgor, Faruk; Yanaral, Fatih; Savun, Metin; Ozdemir, Harun; Sarilar, Omer; Binbay, Murat

    2017-07-29

    In this study, we aim to evaluate the accuracy of STONE (stone size, tract length, obstruction, number of involved calyces, and essence/stone density), Clinical Research Office of the Endourological Society (CROES), and Guy's nephrolithometry scoring systems (NSS) in obese patients. The charts of patients who underwent percutaneous nephrolithotomy (PNL) between June 2008 and June 2016 were retrospectively analyzed. Calculations of the STONE, CROES, and Guy's NSS were performed by a resident who was well informed regarding each NSS. Patients were classified under nine scores according to STONE, four grades according to CROES, and four grades according to Guy's NSS. In total, 248 obese patients were enrolled in the study. Stone size was significantly higher in patients without stone-free status (p = 0.001). In patients who were stone-free and those with residual stones, the mean STONE score was 9.71 and 9.23 (p = 0.160), CROES was 172 and 129 (p = 0.001), and Guy's NSS was 1.67 and 2.75 (p = 0.001). Multivariate regression analysis identified the CROES and Guy's NSS were independent factors for PNL success in obese patients (p = 0.01 and p = 0.01, respectively). The CROES and Guy's NSS showed good accuracy with PNL success (AUC = 0.777 and AUC = 0.844, respectively). None of the three NSS systems were statically associated with a complication rate (p = 0.23 for STONE, p = 0.14 for CROES, and p = 0.51 for Guy's NSS). Our study demonstrated that CROES and Guy's NSS were independent predictors of stone-free rate following PNL in obese patients. Our study also revealed that three of the NSSs were not useful for predicting PNL complications in obese patients.

  3. The effectiveness of stone ash and volcanic ash of mount Sinabung as a filler on the initial strength of self-compacting concrete

    Science.gov (United States)

    Karolina, R.; Muhammad, W.; Saragih, M. D. S. M.; Mustaqa, T.

    2018-02-01

    Self Compacting Concrete is a concrete variant that has a high degree of workability and also has great initial strength, but low water cement factor. It is also self-flowable that can be molded on formwork with a very little or no compacted use of compactors. This concrete, using a variety of aggregate sizes, aggregate portions and superplasticizer admixture to achieve a special viscosity that allows it to flow on its own without the aid of a compactor. Lightweight concrete brick is a type of brick made from cement, sand, water, and developers. Lightweight concrete bricks are divided into 2 based on the developed materials used are AAC (Autoclave Aerated Concrete) using aluminum paste and CLC (Cellular Lightweight Concrete) that use Foaming Agent from BASF as a developer material. In this experiment, the lightweight bricks that will be made are CLC type which uses Foaming Agent as the developer material by mixing the Ash Stone produced by Stone Crusher machine which has the density of 2666 kg / m3 as Partial Pair Substitution. In this study the variation of Ash Stone used is 10%, 15%, and 20% of the planned amount of sand. After doing the tasting the result is obtained for 10% variation. Compressive Strength and Absorption Increase will decrease by 25.07% and 39.005% and Variation of 15% compressive strength will decrease by 65,8% and decrease of absorbtion equal to 17,441% and variation of 20% compressive strength will decreased by 67,4 and absorption increase equal to 17,956%.

  4. Can stone density on plain radiography predict the outcome of extracorporeal shockwave lithotripsy for ureteral stones?

    Science.gov (United States)

    Lim, Ki Hong; Jung, Jin-Hee; Kwon, Jae Hyun; Lee, Yong Seok; Bae, Jungbum; Cho, Min Chul; Lee, Kwang Soo

    2015-01-01

    Purpose The objective was to determine whether stone density on plain radiography (kidney-ureter-bladder, KUB) could predict the outcome of extracorporeal shockwave lithotripsy (ESWL) for ureteral stones. Materials and Methods A total of 223 patients treated by ESWL for radio-opaque ureteral stones of 5 to 20 mm were included in this retrospective study. All patients underwent routine blood and urine analyses, plain radiography (KUB), and noncontrast computed tomography (NCCT) before ESWL. Demographic, stone, and radiological characteristics on KUB and NCCT were analyzed. The patients were categorized into two groups: lower-density (LD) group (radiodensity less than or equal to that of the 12th rib, n=163) and higher-density (HD) group (radiodensity greater than that of the 12th rib, n=60). Stone-free status was assessed by KUB every week after ESWL. A successful outcome was defined as stone free within 1 month after ESWL. Results Mean stone size in the LD group was significantly smaller than that in the HD group (7.5±1.4 mm compared with 9.9±2.9 mm, p=0.002). The overall success rates in the LD and HD groups were 82.1% and 60.0%, respectively (p=0.007). The mean duration of stone-free status and average number of SWL sessions required for success in the two groups were 21.7 compared with 39.2 days and 1.8 compared with 2.3, respectively (pESWL since colic and radiodensity of the stone on KUB were independent predictors of successful ESWL. Conclusions Our data suggest that larger stone size, longer time to ESWL, and ureteral stones with a radiodensity greater than that of the 12th rib may be at a relatively higher risk of ESWL failure 1 month after the procedure. PMID:25598937

  5. Reactions between rocks and the hydroxides of calcium, sodium and potassium: Progress report no. 2

    International Nuclear Information System (INIS)

    Van Aardt, J.H.P.; Visser, S.

    1982-01-01

    Pulversed rocks were mixed with water, and Ca(OH) 2 and NaOH were added to form slurries which were stored at 22 degree Celsius, 40 degrees Celsius and 80 degrees Celsius. The reaction products were identified by means of X-ray diffraction procedures. The effect of adding Al(OH) 3 , Mg(OH) 2 and amorphous SiO 2 to the slurries was also studied. Similar slurries using portland cement on the one hand and milled granulated blastfurnace slag plus Ca(OH) 2 on the other hand instead of the Ca(OH) 2 were examined. On the basis of the findings, suggestions are made as to the nature and composition of the compounds which are responsible for expansive alkali-aggregate reactions. Mortar specimens using portland cement and in some instances milled granulated blastfurnace slag as the binder and various rocks as aggregate were immersed in caustic soda solutions at 40 degrees Celsius and 80 degrees Celsius. Their expansion was determined at regular intervals. It was shown which rocks are likely to give expansion and that expansion can be reduced if the Ca(OH) 2 is bound by means of Al(OH) 3 , for instance. The procedure whereby mortar specimens are immersed in alkali solutions might be developed as a rapid test for assessing whether and to what extent aggregates are alkali susceptible

  6. Trends in urological stone disease.

    Science.gov (United States)

    Turney, Benjamin W; Reynard, John M; Noble, Jeremy G; Keoghane, Stephen R

    2012-04-01

    To summarize the changes in prevalence and treatment of upper urinary tract stone disease in the UK over the last 10 years. Data from the Hospital Episode Statistics (HES) website (http://www.hesonline.nhs.uk) were extracted, summarized and presented. The number of upper urinary tract stone hospital episodes increased by 63% to 83,050 in the 10-year period. The use of shock wave lithotripsy (SWL) for treating all upper tract stones increased from 14,491 cases in 2000-2001 to 22,402 cases in 2010 (a 55% increase) with a 69% increase in lithotripsy for renal stones. There was a 127% increase in the number of ureteroscopic stone treatments from 6,283 to 14,242 cases over the 10-year period with a 49% increase from 2007/2008 to 2009/2010. There was a decline in open surgery for upper tract stones from 278 cases in 2000/2001 to 47 cases in 2009/2010 (an 83% reduction). Treatment for stone disease has increased substantially in comparison with other urological activity. In 2009/2010, SWL was performed almost as frequently as transurethral resection of the prostate or transurethral resection of bladder tumour, ureteroscopy for stones was performed more frequently than nephrectomy, radical prostatectomy and cystectomy combined, and percutaneous nephrolithotomy was performed more frequently than cystectomy. The present study highlights the increase in prevalence and treatment of stone disease in the UK over the last 10 years. If this trend continues it has important implications for workforce planning, training, service delivery and research in the field of urolithiasis. © 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.

  7. Thermal volume changes in clays and clay-stones

    International Nuclear Information System (INIS)

    Delage, P.; Sulem, J.; Mohajerani, M.; Tang, A.M.; Monfared, M.

    2012-01-01

    Document available in extended abstract form only. The disposal of high activity exothermic radioactive waste at great depth in clay host rocks will induce a temperature elevation that has been investigated in various underground research laboratories in Belgium, France and Switzerland through in-situ tests. Thermal effects are better known in clays (in particular Boom clay) than in clay-stone (e.g. Opalinus clay and Callovo-Oxfordian clay-stone). In terms of volume changes, Figure 1 confirms the findings of Hueckel and Baldi (1990) that volume changes depend on the over-consolidation ratio (OCR) of the clay. In drained conditions, normally consolidated clays exhibit plastic contraction when heated, whereas over-consolidated clay exhibit elastic dilation. The nature of thermal volume changes in heated clays obviously has a significant effect on thermally induced pore pressures, when drainage is not instantaneous like what occurs in-situ. Compared to clays, the thermal volume change behaviour of clay-stones is less well known than that of clays. clay-stone are a priori suspected to behave like over-consolidated clays. In this paper, a comparison of recent results obtained in the laboratory on the drained thermal volume changes of clay-stones is presented and discussed. It is difficult to run drained mechanical tests in clay-stones like the Opalinus clay and the Callovo-Oxfordian clay-stone because of their quite low permeability (10 -12 - 10 -13 m/s). This also holds true for thermal tests. Due to the significant difference in thermal expansion coefficient between minerals and water, it is necessary to adopt very slow heating rate (0.5 - 1 C/h) to avoid any thermal pressurization. To do so, a new hollow cylinder apparatus (100 mm external diameter, 60 mm internal diameter) with lateral drainages reducing the drainage length to half the sample thickness (10 mm) has been developed (Monfared et al. 2011). The results of a drained cyclic thermal test carried out on

  8. Mechanics, microstructure and AMS evolution of a synthetic porphyritic calcite aggregate deformed in torsion

    Czech Academy of Sciences Publication Activity Database

    Marques, F. O.; Machek, Matěj; Roxerová, Zuzana; Burg, J.-P.; Almqvist, B. S. G.

    2015-01-01

    Roč. 655, August (2015), s. 41-57 ISSN 0040-1951 Institutional support: RVO:67985530 Keywords : experimental rock deformation * porphyritic calcite aggregate * EBSD and plastic deformation Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.650, year: 2015

  9. Regional differences in constituents of gall stones.

    Science.gov (United States)

    Ashok, M; Nageshwar Reddy, D; Jayanthi, V; Kalkura, S N; Vijayan, V; Gokulakrishnan, S; Nair, K G M

    2005-01-01

    The pathogenesis of pigment and mixed gall stone formation remains elusive. The elemental constituents of gall stones from southern states of Tamil Nadu, Kerala and Karnataka have been characterized. Our aim was to determine the elemental concentration of representative samples of pigment, mixed and cholesterol gall stones from Andhra Pradesh using proton-induced X-ray emission (PIXE) using a 3 MV horizontal pelletron accelerator. Pigment gall stones had significantly high concentrations of copper, iron and lead; chromium was absent. Except for iron all these elements were significantly low in cholesterol gall stones and intermediate levels were seen in mixed gall stones. Highest concentrations of chromium was seen in cholesterol and titanium in mixed gall stones respectively; latter similar to other southern states. Arsenic was distinctly absent in cholesterol and mixed gall stones. The study has identified differences in elemental components of the gall stones from Andhra Pradesh.

  10. The economics of stone disease.

    Science.gov (United States)

    Canvasser, Noah E; Alken, Peter; Lipkin, Michael; Nakada, Stephen Y; Sodha, Hiren S; Tepeler, Abdulkadir; Lotan, Yair

    2017-09-01

    The rising prevalence of kidney stone disease is associated with significant costs to healthcare systems worldwide. This is in part due to direct procedural and medical management costs, as well as indirect costs to health systems, patients, and families. A number of manuscripts evaulating the economics of stone disease have been published since the 2008s International Consultation on Stone Disease. These highlight costs associated with stone disease, including acute management, surgical management, and medical management. This work hopes to highlight optimization in care by reducing inefficient treatments and maximizing cost-efficient preventative strategies.

  11. Non-destructive sampling of rock-dwelling microbial communities using sterile adhesive tape.

    Science.gov (United States)

    Cutler, Nick A; Oliver, Anna E; Viles, Heather A; Whiteley, Andrew S

    2012-12-01

    Building stone provides a habitat for an array of microorganisms, many of which have been demonstrated to have a deleterious effect on the appearance and/or structural integrity of stone masonry. It is essential to understand the composition and structure of stone-dwelling (lithobiontic) microbial communities if successful stone conservation strategies are to be applied, particularly in the face of global environmental change. Ideally, the techniques used to sample such assemblages should be non-destructive due to the sensitive conservation status of many stone buildings. This paper quantitatively assesses the performance of sterile adhesive tape as a non-destructive sampling technique and compares the results of tape sampling with an alternative, destructive, sampling method. We used DNA fingerprinting (TRFLP) to characterise the algal, fungal and bacterial communities living on a stone slab. Our results demonstrate that tape sampling may be used to collect viable quantities of microbial DNA from environmental samples. This technique is ideally suited to the sampling of microbial biofilms, particularly when these communities are dominated by green algae. It provides a good approximation of total community diversity (i.e. the aggregate diversity of epilithic and endolithic communities). Tape sampling is straightforward, rapid and cost effective. When combined with molecular analytical techniques, this sampling method has the potential to make a major contribution to efforts to understand the structure of lithobiontic microbial communities and our ability to predict the response of such communities to future environmental change. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Comparative Study between Digital Tomosynthesis and Endoscopic Retrograde Cholangio pancreatography for the Evaluation of Common Bile Duct Stones: Focus on Detection and Stone Conspicuity

    International Nuclear Information System (INIS)

    Huh, Ji Mi; Baek, Seung Yon; Hwang, Yun Mi; Lee, Jeong Kyong; Kim, Yoo Kyung; Yi, Sun Young

    2011-01-01

    To compare digital tomosynthesis with endoscopic retrograde cholangiopancreatography (ERCP) for the evaluation of common bile duct (CBD) stones as a complementary diagnostic tool. Ninety six consecutive patients clinically suspected of having CBD stones underwent ERCP and digital tomosynthesis over 22 months, from December, 2008 to May, 2010. Fourteen patients were excluded. Therefore 82 patients were included in this study. The images were retrospectively reviewed to compare the results with the final analysis based on the consensus of two abdominal radiologists. An evaluation of the presence of CBD stones was followed by a determination of the margins for the stones, scored with a five-point conspicuity scale. Among the 82 patients, 54 collectively had 89 CBD stones and 28 had no stones. The sensitivity and specificity for the detection of CBD stones were 91.0% and 80.6% for ERCP, 92.1% and 93.5% for digital tomosynthesis, respectively. The average score was 3.29 for ERCP and 3.89 for digital tomosynthesis in 77 similar detected stones. Digital tomosynthesis demonstrated significantly better conspicuity than ERCP (p = 0.001). Digital tomosynthesis is an effective and complementary diagnostic method for the evaluation of CBD stones.

  13. The bioreceptivity of building stone

    Science.gov (United States)

    Mauko Pranjić, Alenka; Mulec, Janez; Muck, Tadeja; Hladnik, Aleš; Mladenovič, Ana

    2015-04-01

    Bioreceptivity is an intrinsic property of stone, and is defined as the ability of a material to be colonized by living organisms. The fouling and staining of building stone material due to the activity of microorganisms presents a serious problem in modern as well as historical buildings, not only due to the aesthetic impact but also due to the deterioration of the material. Biological colonisation on stone materials is influenced by a number of factors, e.g. the intrinsic properties of the stone (porosity, roughness, permeability, mineral composition), environmental parameters (e.g. solar radiation, temperature, water regime, climate, etc.), and specific microclimatic parameters (e.g. orientation, exposure to shadow, permanent capillary humidity, etc.). In order to assess the bioreceptivity of building stones, use is often made of artificial colonisation experiments compromising the inoculation of stones with a single species or a few isolated strains under laboratory conditions. In the present work the authors present the development of a method for the determination of bioreceptivity, as well as a study of the bioreceptivity of selected natural stone versus the latter's intrinsic properties. Field examples of biodeterioration are also presented. The study was supported by the Slovenian Research Agency (L1-5453).

  14. Modeling of Micro Deval abrasion loss based on some rock properties

    Science.gov (United States)

    Capik, Mehmet; Yilmaz, Ali Osman

    2017-10-01

    Aggregate is one of the most widely used construction material. The quality of the aggregate is determined using some testing methods. Among these methods, the Micro Deval Abrasion Loss (MDAL) test is commonly used for the determination of the quality and the abrasion resistance of aggregate. The main objective of this study is to develop models for the prediction of MDAL from rock properties, including uniaxial compressive strength, Brazilian tensile strength, point load index, Schmidt rebound hardness, apparent porosity, void ratio Cerchar abrasivity index and Bohme abrasion test are examined. Additionally, the MDAL is modeled using simple regression analysis and multiple linear regression analysis based on the rock properties. The study shows that the MDAL decreases with the increase of uniaxial compressive strength, Brazilian tensile strength, point load index, Schmidt rebound hardness and Cerchar abrasivity index. It is also concluded that the MDAL increases with the increase of apparent porosity, void ratio and Bohme abrasion test. The modeling results show that the models based on Bohme abrasion test and L type Schmidt rebound hardness give the better forecasting performances for the MDAL. More models, including the uniaxial compressive strength, the apparent porosity and Cerchar abrasivity index, are developed for the rapid estimation of the MDAL of the rocks. The developed models were verified by statistical tests. Additionally, it can be stated that the proposed models can be used as a forecasting for aggregate quality.

  15. Association between dental pulp stones and calcifying nanoparticles.

    Science.gov (United States)

    Zeng, Jinfeng; Yang, Fang; Zhang, Wei; Gong, Qimei; Du, Yu; Ling, Junqi

    2011-01-07

    The etiology of dental pulp stones, one type of extraskeletal calcification disease, remains elusive to date. Calcifying nanoparticles (CNPs), formerly referred to as nanobacteria, were reported to be one etiological factor in a number of extraskeletal calcification diseases. We hypothesized that CNPs are involved in the calcification of the dental pulp tissue, and therefore investigated the link between CNPs and dental pulp stones. Sixty-five freshly collected dental pulp stones, each from a different patient, were analyzed. Thirteen of the pulp stones were examined for the existence of CNPs in situ by immunohistochemical staining (IHS), indirect immunofluorescence staining (IIFS), and transmission electron microscope (TEM). The remaining 52 pulp stones were used for isolation and cultivation of CNPs; the cultured CNPs were identified and confirmed via their shape and growth characteristics. Among the dental pulp stones examined in situ, 84.6% of the tissue samples staines positive for CNPs antigen by IHS; the corresponding rate by IIFS was 92.3 %. In 88.2% of the cultured samples, CNPs were isolated and cultivated successfully. The CNPs were visible under TEM as 200-400 nm diameter spherical particles surrounded by a compact crust. CNPs could be detected and isolated from a high percentage of dental pulp stones, suggesting that CNPs might play an important role in the calcification of dental pulp.

  16. Geochemical studies of backfill aggregates, lake sediment cores and the Hueco Bolson Aquifer

    Science.gov (United States)

    Thapalia, Anita

    This dissertation comprises of three different researches that focuses on the application of geochemistry from aggregates, lake sediment cores and Hueco Bolson Aquifer. Each study is independent and presented in the publication format. The first chapter is already published and the second chapter is in revision phase. Overall, three studies measure the large scale (field) as well as bench scale (lab) water-rock interactions influenced by the climatic and anthropogenic factors spans from the field of environmental geology to civil engineering. The first chapter of this dissertation addresses the chemical evaluation of coarse aggregates from six different quarries in Texas. The goal of this work is to find out the best geochemical methods for assessing the corrosion potential of coarse aggregates prior to their use in mechanically stabilized earth walls. Electrochemical parameters help to define the corrosion potential of aggregates following two different leaching protocols. Testing the coarse and fine aggregates demonstrate the chemical difference due to size-related kinetic leaching effects. Field fines also show different chemistry than the bulk rock indicating the weathering impact on carbonate rocks. The second chapter investigates zinc (Zn) isotopic signatures from eight lake sediment cores collected both from pristine lakes and those impacted by urban anthropogenic contamination. Zinc from the natural weathering of rocks and anthropogenic atmospheric pollutants are transported to these lakes and the signatures are recorded in the sediments. Isotopic analysis of core samples provides the signature of anthropogenic contamination sources. Dated sediment core and isotopic analysis can identify Zn inputs that are correlated to the landuse and population change of the watersheds. Comparison of isotopic data from both pristine and urban lake sediment core also serves as an analog in other lake sediment cores in the world. The third chapter studies on Hueco Bolson

  17. Aggregation of Frenkel defects under irradiation: a mesoscopic approach

    International Nuclear Information System (INIS)

    Soppe, W.; Kotomin, E.

    1993-08-01

    The radiation-induced aggregation of Frenkel defects in solids is studied in terms of a mesoscopic approach. The asymmetry in elastic interactions between mobile interstitials (I-I) and between interstitials and vacancies (I-V) plays a decisive role in the aggregation of similar defects. The conditions for defect aggregation are studied in detail for NaCl crystals. The critical dose rate for aggregation has been calculated as a function of the temperature as well as the aggregation rate as a function of temperature and dose rate. Furthermore, the role of deep traps (like impurities and di-vacancies), reducing the mobility of interstitials, and the role of dislocations serving as sinks for interstitials, are studied. The aggregation appears to reach a maximum at a distinct temperature which is in agreement both with experiment and the Jain-Lidiard theory. The model also predicts a shift of this maximum towards lower temperatures if the dose rate is decreased. The consequences of the model for the disposal of nuclear waste in rock salt formations, are briefly discussed. (orig.)

  18. Utilization of Ripe Coconut Fiber in Stone Matrix Asphalt Mixes

    Directory of Open Access Journals (Sweden)

    Mahabir Panda

    2013-12-01

    Full Text Available Stone Matrix Asphalt (SMA is a gap graded mix; characterized by higher proportion of coarse aggregate, lower proportion of middle size aggregate and higher proportion of mineral filler. In the present laboratory study, commonly available one conventional VG 30 bitumen and another modified binder, namely CRMB 60 have been used along with a non-conventional natural fiber, namely coconut fiber which is abundantly available in India to provide improved engineering properties and at the same time preventing the usual draining of binder in SMA. The role of a particular binder and fiber with respect to their concentrations in the mix is studied for various engineering properties. Marshall procedure has been followed to determine the optimum binder and optimum fiber contents and also to study the relative advantages of fiber addition in the SMA mixtures. Thereafter, the engineering properties under both static as well as repeated load conditions and moisture susceptibility characteristics have been studied. It is observed that only a marginal 0.3% coconut fiber addition brings significant improvement in the engineering properties of SMA mixes.

  19. Upper urinary tract stone disease in patients with poor performance status: active stone removal or conservative management?

    Science.gov (United States)

    Yamashita, Shimpei; Kohjimoto, Yasuo; Hirabayashi, Yasuo; Iguchi, Takashi; Iba, Akinori; Higuchi, Masatoshi; Koike, Hiroyuki; Wakamiya, Takahito; Nishizawa, Satoshi; Hara, Isao

    2017-11-16

    It remains controversial as to whether active stone removal should be performed in patients with poor performance status because of their short life expectancy and perioperative risks. Our objectives were to evaluate treatment outcomes of active stone removal in patients with poor performance status and to compare life prognosis with those managed conservatively. We retrospectively reviewed 74 patients with Eastern Cooperative Oncology Group performance status 3 or 4 treated for upper urinary tract calculi at our four hospitals between January 2009 and March 2016. Patients were classified into either surgical treatment group or conservative management group based on the presence of active stone removal. Stone-free rate and perioperative complications in surgical treatment group were reviewed. In addition, we compared overall survival and stone-specific survival between the two groups. Cox proportional hazards analysis was performed to investigate predictors of overall survival and stone-specific survival. Fifty-two patients (70.3%) underwent active stone removal (surgical treatment group) by extracorporeal shock wave lithotripsy (n = 6), ureteroscopy (n = 39), percutaneous nephrolithotomy (n = 6) or nephrectomy (n = 1). The overall stone-free rate was 78.8% and perioperative complication was observed in nine patients (17.3%). Conservative treatment was undergone by 22 patients (29.7%) (conservative management group). Two-year overall survival rates in surgical treatment and conservative management groups were 88.0% and 38.4%, respectively (p performance status could be performed safely and effectively. Compared to conservative management, surgical stone treatment achieved longer overall survival and stone-specific survival.

  20. Properties of concrete blocks prepared with low grade recycled aggregates.

    Science.gov (United States)

    Poon, Chi-Sun; Kou, Shi-cong; Wan, Hui-wen; Etxeberria, Miren

    2009-08-01

    Low grade recycled aggregates obtained from a construction waste sorting facility were tested to assess the feasibility of using these in the production of concrete blocks. The characteristics of the sorted construction waste are significantly different from that of crushed concrete rubbles that are mostly derived from demolition waste streams. This is due to the presence of higher percentages of non-concrete components (e.g. >10% soil, brick, tiles etc.) in the sorted construction waste. In the study reported in this paper, three series of concrete block mixtures were prepared by using the low grade recycled aggregates to replace (i) natural coarse granite (10mm), and (ii) 0, 25, 50, 75 and 100% replacement levels of crushed stone fine (crushed natural granite concrete blocks. Test results on properties such as density, compressive strength, transverse strength and drying shrinkage as well as strength reduction after exposure to 800 degrees C are presented below. The results show that the soil content in the recycled fine aggregate was an important factor in affecting the properties of the blocks produced and the mechanical strength deceased with increasing low grade recycled fine aggregate content. But the higher soil content in the recycled aggregates reduced the reduction of compressive strength of the blocks after exposure to high temperature due probably to the formation of a new crystalline phase. The results show that the low grade recycled aggregates obtained from the construction waste sorting facility has potential to be used as aggregates for making non-structural pre-cast concrete blocks.

  1. Natural radioactivity and radon exhalation rate in Brazilian igneous rocks

    Energy Technology Data Exchange (ETDEWEB)

    Moura, C.L.; Artur, A.C. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Bonotto, D.M., E-mail: danielbonotto@yahoo.com.b [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Guedes, S. [Departamento de Cronologia e Raios Cosmicos, Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas (UNICAMP), Rua Sergio Buarque de Holanda No. 777, CEP 13083-859, Campinas, Sao Paulo (Brazil); Martinelli, C.D. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil)

    2011-07-15

    This paper reports the natural radioactivity of Brazilian igneous rocks that are used as dimension stones, following the trend of other studies on the evaluation of the risks to the human health caused by the rocks radioactivity as a consequence of their use as cover indoors. Gamma-ray spectrometry has been utilized to determine the {sup 40}K, {sup 226}Ra and {sup 232}Th activity concentrations in 14 rock types collected at different quarries. The following activity concentration range was found: 12.18-251.90 Bq/kg for {sup 226}Ra, 9.55-347.47 Bq/kg for {sup 232}Th and 407.5-1615.0 Bq/kg for {sup 40}K. Such data were used to estimate Ra{sub eq}, H{sub ex} and I{sub {gamma}}, which were compared with the threshold limit values recommended in literature. They have been exceeded for Ra{sub eq} and H{sub ex} in five samples, where the highest indices corresponded to a rock that suffered a process of ductile-brittle deformation that caused it a microbrecciated shape. The exhalation rate of Rn and daughters has also been determined in slabs consisting of rock pieces {approx}10 cm-long, 5 cm-wide and 3 cm-thick. It ranged from 0.24 to 3.93 Bq/m{sup 2}/h and exhibited significant correlation with eU (={sup 226}Ra), as expected. The results indicated that most of the studied rocks did not present risk to human health and may be used indoors, even with low ventilation. On the other hand, igneous rocks that yielded indices above the threshold limit values recommended in literature may be used outdoors without any restriction or indoors with ample ventilation.

  2. EVALUATION OF CONSISTENCY AND SETTING TIME OF IRANIAN DENTAL STONES

    Directory of Open Access Journals (Sweden)

    F GOL BIDI

    2000-09-01

    Full Text Available Introduction. Dental stones are widely used in dentistry and the success or failure of many dental treatments depend on the accuracy of these gypsums. The purpose of this study was the evaluation of Iranian dental stones and comparison between Iranian and foreign ones. In this investigation, consistency and setting time were compared between Pars Dendn, Almas and Hinrizit stones. The latter is accepted by ADA (American Dental Association. Consistency and setting time are 2 of 5 properties that are necessitated by both ADA specification No. 25 and Iranian Standard Organization specification No. 2569 for evaluation of dental stones. Methods. In this study, the number and preparation of specimens and test conditions were done according to the ADA specification No. 25 and all the measurements were done with vicat apparatus. Results. The results of this study showed that the standard consistency of Almas stone was obtained by 42ml water and 100gr powder and the setting time of this stone was 11±0.03 min. Which was with in the limits of ADA specification (12±4 min. The standard consistency of Pars Dandan stone was obrianed by 31ml water and 100 gr powder, but the setting time of this stone was 5± 0.16 min which was nt within the limits of ADA specification. Discussion: Comparison of Iranian and Hinrizit stones properties showed that two probable problems of Iranian stones are:1- Unhemogrnousity of Iranian stoned powder was caused by uncontrolled temperature, pressure and humidity in the production process of stone. 2- Impurities such as sodium chloride was responsible fo shortening of Pars Dendens setting time.

  3. Unravelling ground stone life histories: the spatial organization of stone tools and human activities at LN Makriyalos, Greece:

    OpenAIRE

    Tsoraki, Christina

    2007-01-01

    Unlike previous studies of ground stone technology in the Greek Neolithic, this paper follows a more contextualised approach by looking at contexts of deposition of ground stone from Late Neolithic Makriyalos, Northern Greece. The patterns attested in the distribution of ground stone objects between domestic and communal areas will be discussed in terms of the spatial and social contexts of tool use, curation and deposition, contributing to wider discussions about the way acts of production, ...

  4. A comparative study of mud-like and coralliform calcium carbonate gallbladder stones.

    Science.gov (United States)

    Ma, Rui-Hong; Luo, Xiao-Bing; Wang, Xiao-Feng; Qiao, Tie; Huang, Hai-Yi; Zhong, Hai-Qiang

    2017-07-01

    To gain insight to underlying mechanism of the formation of calcium carbonate (CaCO 3 ) gallbladder stones, we did comparative study of stones with mud appearance and those with coralliform appearance. A total of 93 gallbladder stones with mud appearance and 50 stones with coralliform appearance were analyzed. The appearance, color, texture, and the detection of Clonorchis sinensis eggs by microscopic examination were compared between the two groups. Then, the material compositions of stones were analyzed using Fourier Transform Infrared spectroscopy and the spectrogram characteristics were compared. Moreover, microstructure characteristics of the two kinds of stones were observed and compared with Scanning Electron Microscopy. Mud-like gallbladder stones were mainly earthy yellow or brown with brittle or soft texture, while coralliform stones were mainly black with extremely hard texture, the differences between the two groups was significant (p mud-like gallbladder stones were CaCO 3 stones, and mainly aragonite; while all of the coralliform stones were CaCO 3 stones, and mainly calcite (p mud-like CaCO 3 stones was lower than that in coralliform CaCO 3 stones (p Mud-like CaCO 3 stones mainly happened to patients with cystic duct obstruction. Clonorchis sinensis infection was mainly associated with coralliform (calcite) CaCO 3 stones. Cystic duct obstruction was mainly associated with mud-like (aragonite) CaCO 3 stones. © 2017 Wiley Periodicals, Inc.

  5. Volcanic Aggregates from Azores and Madeira Archipelagos (Portugal): An Overview Regarding the Alkali Silica Reactions

    Science.gov (United States)

    Medeiros, Sara; Ramos, Violeta; Fernandes, Isabel; Nunes, João Carlos; Fournier, Benoit; Santos Silva, António; Soares, Dora

    2017-12-01

    Alkali-silica reaction (ASR) is a type of deterioration that has been causing serious expansion, cracking and durability/operational issues in concrete structures worldwide. The presence of sufficient moisture, high alkali content in the cement paste and reactive forms of silica in the aggregates are the required conditions for this reaction to occur. Reactive aggregates of volcanic nature have been reported in different countries such as Japan, Iceland and Turkey, among others. The presence of silica minerals and SiO2-rich volcanic glass is regarded as the main cause for the reactivity of volcanic rocks. In Portugal, volcanic aggregates are mainly present in Azores and Madeira Archipelagos and, for several years, there was no information regarding the potential alkali-reactivity of these rocks. Since the beginning of this decade some data was obtained by the work of Medeiros (2011) and Ramos (2013) and by the national research projects ReAVA, (Characterization of potential reactivity of the volcanic aggregates from the Azores Archipelago: implications on the durability of concrete structures) and IMPROVE (Improvement of performance of aggregates in the inhibition of alkali-aggregate reactions in concrete), respectively. In order to investigate the potential alkali-reactivity of aggregates from both archipelagos, a total of sixteen aggregates were examined under the optical microscope and, some of them, also under the Scanning Electron Microscope with Energy Dispersive X-ray Spectroscopy. A set of geochemical analyses and laboratory expansion tests were also performed on those volcanic aggregates. The main results showed that the presence of volcanic glass is rare in both archipelagos and that the samples of Madeira Archipelago contain clay minerals (mainly from scoria/tuff formations inter-layered with the lava flows), which can play a role in concrete expansion. The results of the laboratory tests showed that one of the samples performed as potentially reactive

  6. Classification Scheme for Diverse Sedimentary and Igneous Rocks Encountered by MSL in Gale Crater

    Science.gov (United States)

    Schmidt, M. E.; Mangold, N.; Fisk, M.; Forni, O.; McLennan, S.; Ming, D. W.; Sumner, D.; Sautter, V.; Williams, A. J.; Gellert, R.

    2015-01-01

    The Curiosity Rover landed in a lithologically and geochemically diverse region of Mars. We present a recommended rock classification framework based on terrestrial schemes, and adapted for the imaging and analytical capabilities of MSL as well as for rock types distinctive to Mars (e.g., high Fe sediments). After interpreting rock origin from textures, i.e., sedimentary (clastic, bedded), igneous (porphyritic, glassy), or unknown, the overall classification procedure (Fig 1) involves: (1) the characterization of rock type according to grain size and texture; (2) the assignment of geochemical modifiers according to Figs 3 and 4; and if applicable, in depth study of (3) mineralogy and (4) geologic/stratigraphic context. Sedimentary rock types are assigned by measuring grains in the best available resolution image (Table 1) and classifying according to the coarsest resolvable grains as conglomerate/breccia, (coarse, medium, or fine) sandstone, silt-stone, or mudstone. If grains are not resolvable in MAHLI images, grains in the rock are assumed to be silt sized or smaller than surface dust particles. Rocks with low color contrast contrast between grains (e.g., Dismal Lakes, sol 304) are classified according to minimum size of apparent grains from surface roughness or shadows outlining apparent grains. Igneous rocks are described as intrusive or extrusive depending on crystal size and fabric. Igneous textures may be described as granular, porphyritic, phaneritic, aphyric, or glassy depending on crystal size. Further descriptors may include terms such as vesicular or cumulate textures.

  7. Use of the probability of stone formation (PSF score to assess stone forming risk and treatment response in a cohort of Brazilian stone formers

    Directory of Open Access Journals (Sweden)

    Benjamin Turney

    2014-08-01

    Full Text Available Introduction The aim was to confirm that PSF (probability of stone formation changed appropriately following medical therapy on recurrent stone formers. Materials and Methods Data were collected on 26 Brazilian stone-formers. A baseline 24-hour urine collection was performed prior to treatment. Details of the medical treatment initiated for stone-disease were recorded. A PSF calculation was performed on the 24 hour urine sample using the 7 urinary parameters required: voided volume, oxalate, calcium, urate, pH, citrate and magnesium. A repeat 24-hour urine sample was performed for PSF calculation after treatment. Comparison was made between the PSF scores before and during treatment. Results At baseline, 20 of the 26 patients (77% had a high PSF score (> 0.5. Of the 26 patients, 17 (65% showed an overall reduction in their PSF profiles with a medical treatment regimen. Eleven patients (42% changed from a high risk (PSF > 0.5 to a low risk (PSF 0.5 during both assessments. Conclusions The PSF score reduced following medical treatment in the majority of patients in this cohort.

  8. Management of ureteric stone in pediatric patients

    Directory of Open Access Journals (Sweden)

    Eugene Minevich

    2010-01-01

    Full Text Available The management of ureteral stones in children is becoming more similar to that in adults. A number of factors must be taken into account when selecting one′s choice of therapy for ureteral stone in children such as the size of the stone, its location, its composition, and urinary tract anatomy. Endoscopic lithotripsy in children has gradually become a major technique for the treatment of ureteral stones. The stone-free rate following urteroscopic lithotripsy for ureteral stones has been reported in as high as 98.5-100%. The safety and efficacy of Holmium:YAG laser lithotripsy make it the intracorporeal lithotriptor of choice. Given its minimally invasive features, extracorporeal shock wave lithotripsy (ESWL has become a primary mode of treatment for the pediatric patients with reno-ureteral stones. Stone-free rates have been reported from 59% to 91% although some patients will require more than one treatment session for stone clearance. It appears that the first-line of therapy in the child with distal and mid-ureteral stones should be ureteroscopic lithotripsy. While ESWL is still widely considered the first-line therapy for proximal ureteral calculi, there is an increasing body of evidence that shows that endoscopic or ESWL are equally safe and efficacious in those clinical scenarios. Familiarity with the full spectrum of endourological techniques facilitates a minimally invasive approach to pediatric ureteral stones.

  9. Use of the probability of stone formation (PSF) score to assess stone forming risk and treatment response in a cohort of Brazilian stone formers.

    Science.gov (United States)

    Turney, Benjamin; Robertson, William; Wiseman, Oliver; Amaro, Carmen Regina P R; Leitão, Victor A; Silva, Isabela Leme da; Amaro, João Luiz

    2014-01-01

    The aim was to confirm that PSF (probability of stone formation) changed appropriately following medical therapy on recurrent stone formers. Data were collected on 26 Brazilian stone-formers. A baseline 24-hour urine collection was performed prior to treatment. Details of the medical treatment initiated for stone-disease were recorded. A PSF calculation was performed on the 24 hour urine sample using the 7 urinary parameters required: voided volume, oxalate, calcium, urate, pH, citrate and magnesium. A repeat 24-hour urine sample was performed for PSF calculation after treatment. Comparison was made between the PSF scores before and during treatment. At baseline, 20 of the 26 patients (77%) had a high PSF score (> 0.5). Of the 26 patients, 17 (65%) showed an overall reduction in their PSF profiles with a medical treatment regimen. Eleven patients (42%) changed from a high risk (PSF > 0.5) to a low risk (PSF 0.5) during both assessments. The PSF score reduced following medical treatment in the majority of patients in this cohort.

  10. Investigating the swelling pressure of compacted crushed-Callovo-Oxfordian clay-stone

    International Nuclear Information System (INIS)

    Tang, C. S.; Tang, A. M.; Cui, Y. J.; Delage, P.; Schroeder, C.; De Laure, E.

    2011-01-01

    This paper presents an experimental study on the swelling pressure of heavily compacted crushed Callovo-Oxfordian (COx) clay-stone at a dry unit mass ρ d =2.0 Mg/m 3 using four different methods: constant-volume, swell-reload, zero-swell and adjusted constant-volume method. Results show that the swelling pressure varies in the range of 1-5 MPa and depends significantly on the test method. From the constant-volume tests, it is observed that the swelling behavior during wetting is a function of the suction and depends on both the hydration paths and wetting conditions (e.g. vapor-wetting or liquid-wetting). The swelling pressure decreases significantly with saturation time. To identify the microstructure changes of specimens before and after wetting, mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) tests were performed. It is observed that, after wetting, the large inter-aggregate pores observed in the as-compacted specimen are no longer apparent; the whole pattern is characterized by a general swell of hydrated clay particles, rendering the soil more homogenous. Results from MIP indicated that wetting caused a significant reduction of the entrance diameter of the dominant inter-aggregate pores from 2.1 to 0.5μm whereas intra-aggregate pores were not significantly influenced. (authors)

  11. Advances in percutaneous stone surgery

    OpenAIRE

    Hartman, Christopher; Gupta, Nikhil; Leavitt, David; Hoenig, David; Okeke, Zeph; Smith, Arthur

    2015-01-01

    Treatment of large renal stones has changed considerably in recent years. The increasing prevalence of nephrolithiasis has mandated that urologists perform more surgeries for large renal calculi than before, and this has been met with improvements in percutaneous stone surgery. In this review paper, we examine recent developments in percutaneous stone surgery, including advances in diagnosis and preoperative planning, renal access, patient position, tract dilation, nephroscopes, lithotripsy, ...

  12. Interactions of Various types between Rock and Alkali-Activated Blast Furnace Slag

    Directory of Open Access Journals (Sweden)

    Mec Pavel

    2017-03-01

    Full Text Available Alkali-activated binders (AAB are very intensively studied materials nowadays. Because of possible usage as secondary raw materials, they can be environmentally efficient. Intensive research is focused especially on binder matrix, composition and its structure. For industrial usage, it is necessary to work with some aggregate for the preparation of mortars and concretes. Due to different structures of alkali-activated binders, the interaction with the aggregate will be different in comparison to an ordinary Portland cement binder. This paper deals with the study of interactions between several types of rocks used as aggregate and alkali-activated blast furnace slag. The research was focused especially on mechanical properties of prepared mortars.

  13. Stone-free-rate after extracorporeal shockwave lithotripsy in the management of pediatric renal stones in lower pole and other locations - a comparative study

    International Nuclear Information System (INIS)

    Iqbal, N.; Muhammad, S.; Akhter, S.

    2016-01-01

    To determine a difference in the stone-free-rate among different renal locations in children after extracorporeal shockwave lithotripsy (ESWL). Study Design: A descriptive study. Place and Duration of Study: Urology Department, Shifa International Hospital, Islamabad, Pakistan, from January 2007 to June 2015. Methodology: The study included children who underwent ESWL, divided into three groups based on location of stones in kidney as group A (lower pole stones), group B (upper and mid pole stones) and group C (renal pelvis stone), respectively. ESWL was done by standard technique using Storz Modulith SLX lithotripter 3rd generation. Data was collected by chart review. SPSS version 16 was used for data analysis. Results: Among 76 children with mean age of 7.55 +-4.16 years, 55 (72.4%) were males whereas 21 (27.6%) were females. Mean stone size was 1.08 +-0.59 cm. There were 34, 17 and 25 cases in groups A, B and C, respectively. PostESWL stone-free-rate was 47% in lower pole stones, 70.58% in upper and mid pole stones, and 68% in renal pelvis stones. Hematuria was seen in one patient from each group, sepsis in two patients from each of the mid pole/upper pole and lower pole group, while Steinstrasse in one patient from each group. (author)

  14. The Stones and the Stars Building Scotland's Newest Megalith

    CERN Document Server

    Lunan, Duncan

    2013-01-01

    There are at least 48 identified prehistoric stone circles in Scotland.  In truth, very little is known about the people who erected them, and ultimately about what the stone circles were for.  Most stone circles are astronomically aligned, which has led to the modern debate over the significance of the alignments.  The megaliths certainly represented an enormous cooperative effort, would at the very least have demonstrated power and wealth, and being set away from any dwellings probably served a ceremonial, or perhaps religious, purpose. Observations at the site of the stone circles, of solar, lunar, and stellar events, have already cast light on some of the questions about the construction and use of ancient megalithic observatories. In his capacity as manager of the Glasgow Parks Department Astronomy Project, author Duncan Lunan designed and built in the late 1970s Sighthill, the first astronomically aligned stone circle in Britain in over 3,000 years.  The Stones and the Stars examines the case for as...

  15. PIXE analysis of chinese chicken-blood stone

    International Nuclear Information System (INIS)

    Lin, E.K.; Wang, C.W.; Yu, Y.C.; Liu, T.Y.; Cheng, H.S.; Zhu, H.X.; Yang, H.J.

    1999-01-01

    This paper reports the chemical compositions of chicken-blood stone Ji Xue Shi measured by Proton Induced X-ray Emission (PIXE). The experimental result show that for the red portion of chicken-blood stone, the concentration of Hg is as high as 20 wt%, and the concentration of S can be above 10 wt%. For the non-red portion the main chemical compositions are Al 2 O 3 and SiO 2 . The obtained chemical compositions are close to those of kaolinite for Balin chicken-blood stone, and of pyrophyllite for Changhua chicken-blood stone, respectively. So far many Changhua chicken-blood stones and Balin chicken-blood stones were found in China, the PIXE method can be used to explore the provenance of available chicken-blood stones. (author)

  16. Petrographic and porosimetric study of opuka stones from different construction phases of the medieval Church of the Beheading of St. John the Baptist in Dolní Chabry (Prague, Czech Republic)

    Science.gov (United States)

    Sidova, Katerina; Prikryl, Richard; Weishauptova, Zuzana; Racek, Martin

    2015-04-01

    Opuka as a very fine-grained sedimentary rock deposited during Upper Cretaceous in relatively shallow (hemipelagic) marine conditions in the Bohemian Cretaceous Basin (Czech Republic) represents type of natural stone that has been widely exploited and used for construction from about 9th c. AD. Romanesque churches in Prague and central Bohemia are among the first preserved structures for which the opuka has been used. Question whether very local or more distant sources have been employed represents still unsolved matter. In the recent study, we focus on the detailed analysis of specimens of opuka taken from the Church of the Beheading of St. John the Baptist in Dolní Chabry (Prague). During the previous archaeological survey of the recent church (dated to 12th c. AD), remnants (basements constructed of opuka stone) of three older churches have recognized. The aim of recent material study is recognition of similarities or differences between opuka stones coming from these different construction phases and answering a question, whether material from a single source or from different localities has been employed. The study is based on the detailed petrographic examination using four sets of techniques: (1) microscopic observation (basic optical microscopy supplemented with the electron microscopy with microanalysis and X-ray elemental mapping), (2) X-ray diffraction of insoluble residue (composition of clay fraction and detection of some less organized silica forms), (3) chemical analysis and computation of modal composition by using normative minerals based on known mineralogical composition (input from microscopy and XRD), (4) study of physical properties, specifically by means of mercury porosimetry to quantify complex pore space of these rocks. Based on the results, three basic sets of specimens have been distinguished: (1) opuka stone with low content of carbonates (22-26 wt. %) and with higher content of kaolinite and illite (both WCI and PCI), (2) opuka stone

  17. Optimum nutrition for kidney stone disease.

    Science.gov (United States)

    Heilberg, Ita P; Goldfarb, David S

    2013-03-01

    We summarize the data regarding the associations of individual dietary components with kidney stones and the effects on 24-hour urinary profiles. The therapeutic recommendations for stone prevention that result from these studies are applied where possible to stones of specific composition. Idiopathic calcium oxalate stone-formers are advised to reduce ingestion of animal protein, oxalate, and sodium while maintaining intake of 800 to 1200 mg of calcium and increasing consumption of citrate and potassium. There are few data regarding dietary therapy of calcium phosphate stones. Whether the inhibitory effect of citrate sufficiently counteracts increasing urine pH to justify more intake of potassium and citrate is not clear. Reduction of sodium intake to decrease urinary calcium excretion would also be expected to decrease calcium phosphate stone recurrence. Conversely, the most important urine variable in the causation of uric acid stones is low urine pH, linked to insulin resistance as a component of obesity and the metabolic syndrome. The mainstay of therapy is weight loss and urinary alkalinization provided by a more vegetarian diet. Reduction in animal protein intake will reduce purine ingestion and uric acid excretion. For cystine stones, restriction of animal protein is associated with reduction in intake of the cystine precursor methionine as well as cystine. Reduction of urine sodium results in less urine cystine. Ingestion of vegetables high in organic anion content, such as citrate and malate, should be associated with higher urine pH and fewer stones because the amino acid cystine is soluble in more alkaline urine. Because of their infectious origin, diet has no definitive role for struvite stones except for avoiding urinary alkalinization, which may worsen their development. Published by Elsevier Inc.

  18. Design Tests of Pre Cutting in Light Explosion of Stone Drifts%预掏槽在岩巷光爆中的设计试验

    Institute of Scientific and Technical Information of China (English)

    袁文清

    2015-01-01

    In order to improve the exploration effect and advance rate of stone drifts,focusing on the concept that the free face of explosion in stone drifts advance is little,the paper puts forward the pre cutting concept,describes the rock breaking mechanism of pre cutting,and makes feasibility analysis of pre cutting of stone drifts. It also design for the inclined deep hoe wedge-shape cutting,and conducts ten times cycling tests for light explosion in stone drifts.%为提高岩石巷道的爆破效果和掘进速度,针对岩巷掘进中爆破自由面少,提出预掏槽的概念,阐述了预掏槽的破岩机理,对岩巷预掏槽做了可行性分析,以斜眼深孔楔形掏槽形式对预掏槽进行了设计。

  19. Efficacy of surgical techniques and factors affecting residual stone rate in the treatment of kidney stones.

    Science.gov (United States)

    Aydemir, Hüseyin; Budak, Salih; Kumsar, Şükrü; Köse, Osman; Sağlam, Hasan Salih; Adsan, Öztuğ

    2014-09-01

    In this study, we aimed to evaluate, the efficacy of surgical methods and the factors affecting the residual stone rate by scrutinizing retrospectively the patients who had undergone renal stone surgery. Records of 109 cases of kidney stones who had been surgically treated between January 2010, and July 2013 were reviewed. Patients were divided into three groups in terms of surgical treatment; open stone surgery, percutaneous nephrolithotomy (PNL) and retrograde intrarenal surgery (RIRS). Patients' history, physical examination, biochemical and radiological images and operative and postoperative data were recorded. The patients had undergone PNL (n=74; 67.9%), RIRS (n=22;20.2%), and open renal surgery (n=13; 11.9%). The mean and median ages of the patients were 46±9, 41 (21-75) and, 42 (23-67) years, respectively. The mean stone burden was 2.6±0.7 cm(2) in the PNL, 1.4±0.1 cm(2) in the RIRS, and 3.1±0.9 cm(2) in the open surgery groups. The mean operative times were 126±24 min in the PNL group, 72±12 min in the RIRS group and 82±22 min in the open surgery group. The duration of hospitalisation was 3.1±0.2 days, 1.2±0.3 days and 3.4±1.1 days respectively. While the RIRS group did not need blood transfusion, in the PNL group blood transfusions were given in the PNL (n=18), and open surgery (n=2) groups. Residual stones were detected in the PNL (n=22), open surgery (n=2), and RIRS (n=5) groups. PNL and RIRS have been seen as safe and effective methods in our self application too. However, it should not be forgotten that as a basical method, open surgery may be needed in cases of necessity.

  20. Durability of building stones against artificial salt crystallization

    Science.gov (United States)

    Min, K.; Park, J.; Han, D.

    2005-12-01

    Salts have been known as the most powerful weathering agents, especially when combined with frost action. Salt crystallization test along with freezing-thawing test and acid immersion test was carried out to assess the durability of building stones against weathering. Granite, limestone, marble and basalt were sampled from different quarries in south Korea for this study. One cycle of artificial salt crystallization test was composed of immersion of cored rock specimens in oversaturated solutions of CaCl2, KCl, NaCl and Na2SO4, respectively for 15 hours and successive drying in an oven of 105°C for 3 hours and cooling at room temperature. Tests were performed up to 30 cycles, and specific gravity and ultrasonic velocity were measured after experiencing every 10 cycles and uniaxial compressive strength was measured only after 30 cycles. During the repeated Na2SO4 salt crystallization, some rock samples were gradually deformed excessively and burst after 20 to 30 cycles of test. The variation patterns of physical properties during the salt crystallization tests are too variable to generalize the effect of salt weathering on physical properties but limestone, marble and basalt samples showed relatively greater change of physical properties than granite samples. The recrystallized salts were well observed in the cracks of rock samples through the scanning electron microscope. In the all salt crystallization tests, apparent specific gravities for all tested samples increased generally but not so significantly due to recrystallization of salts. It can be inferred that filling the pores with salt crystals cause the increase of ultrasonic velocity during the early stage of salt crystallization and then in later stages the repeated cycles of salt crystallization result in development of cracks leading decrease of ultrasonic velocity for some rock samples.

  1. Utilização do planejamento experimental em rede simplex no estudo de resíduo de rocha ornamental como filler para obtenção de máxima compacidade Use of simplex lattice experimental design in the study of ornamental rock waste as filler to obtain maximum compaction

    Directory of Open Access Journals (Sweden)

    A. Z. Destefani

    2011-12-01

    Full Text Available A utilização de agregados industrializados vem crescendo ao longo dos anos para atender a grande demanda da construção civil devido ao crescimento econômico do país. O objetivo deste trabalho foi utilizar o planejamento experimental em Rede Simplex para avaliar o efeito da adição do resíduo de rocha ornamental como filler na composição de misturas ternárias (brita 0, pó de pedra e resíduo, que levem a máxima compacidade (densidade seca aparente máxima. Foram tomados dezesseis pontos experimentais, cujos teores dos materiais utilizados variaram de 0 a 100%. O modelo em rede simplex cúbico completo apresentou melhor ajuste aos resultados experimentais, o qual resulta em respostas estatisticamente mais adequadas para as composições estudadas. A superfície de resposta gerada indicou que a densidade seca aparente máxima de 2,0 g/cm³ foi obtida para a composição ternária: 63% de brita 0/17% de pó de pedra/20% de resíduo de rocha ornamental. Portanto, o uso de resíduo de rocha ornamental como filler em agregados para a construção civil pode ser uma alternativa viável para deposição final deste abundante resíduo de forma ambientalmente correta.The use of industrial aggregates has grown over the years to meet the great demand of the civil construction due to the country's economical growth. The aim of this work was to use the experimental design in Simplex Lattice to evaluate the effect of the addition of ornamental rock waste as filler in the composition of ternary mixtures (crushed rock 0, stone powder, rock waste, leading to maximum compaction (maximum apparent dry density. Sixteen experimental points were taken, whose contents of the used materials ranged from 0 to 100%. The complete cubic simplex model showed to best fit to the experimental results, which results in more statistically appropriated responses to the studied compositions. The response surface generated indicated that the maximum apparent dry density (2

  2. The role of second phases for controlling microstructural evolution in polymineralic rocks: A review

    DEFF Research Database (Denmark)

    Herwegh, Marco; Linckens, Jolien; Ebert, Andreas

    2011-01-01

    We present a state-of-the-art review of the microstructural evolution in rocks under static and deformational conditions. First, the general concepts and processes are introduced using monomineralic aggregates. Then, they are expanded into the more complex context of polymineralic rocks...... with a dominant matrix phase. The first part of this contribution delivers information on sample strategies to quantify polymineralic microfabrics. Based on comparisons between microfabrics of monomineralic and polymineralic rocks, we use the common knowledge collected over the past decades for monomineralic......, and deformation mechanisms. We speculate on the effect of mineral reactions during the evolution of microstructures and rheology in polymineralic aggregates at different metamorphic conditions. At the end of the article, we demonstrate the great potential of grain-size evolution maps as microstructural tool...

  3. Astronomical Symbolism in Australian Aboriginal Rock Art

    Science.gov (United States)

    Norris, Ray P.; Hamacher, Duane W.

    2011-05-01

    Traditional Aboriginal Australian cultures include a significant astronomical component, perpetuated through oral tradition and ceremony. This knowledge has practical navigational and calendrical functions, and sometimes extends to a deep understanding of the motion of objects in the sky. Here we explore whether this astronomical tradition is reflected in the rock art of Aboriginal Australians. We find several plausible examples of depictions of astronomical figures and symbols, and also evidence that astronomical observations were used to set out stone arrangements. However, we recognise that the case is not yet strong enough to make an unequivocal statement, and describe our plans for further research.

  4. The Meteoritical Quincentennial: The Stone of Ensisheim 1492-1992

    Science.gov (United States)

    Marvin, U. B.

    1992-07-01

    of God, because never before had such a thing been heard, or seen, or written about. Von der Muhll (1961) and others have asked how such statements could be made when Pliny the Elder wrote of fallen stones as early as the 1st century A.D., and Heynlin de Lapide, at nearby Basel, was translating Pliny's works at the time of the fall. However, expressions such as "never before heard, seen, or written about," spiced the reports of Medieval travelers struggling to describe the marvels of far-off lands. In this instance, the phrases described a marvel that burst upon the people of the upper Rhineland in the course of their daily routines. In truth, nothing ever written could have prepared them for the incandescent fireball, resounding explosion, and the black stone that plunged to Earth at Ensisheim. Unimaginative Eyewitnesses. A boy saw the stone fall and a crowd dug it out of a wheat field. In 1800, the chemist, Charles Barthold, rejected the eyewitness story and concluded that the stone was a common type of rock that could have washed down from a mountainside. In 1803, after meteorites, including the Ensisheim stone, had become accepted as authentic natural phenomena, Joseph Izarn wrote that the boy's testimony should be believed because ignorant persons like him have no imagination and could not possible invent tales about stones from the sky. Izarn's opinion was not eccentric; numerous writings show that it reflected a centuries-old tradition of placing special value on observations by unschooled witnesses. References: Brant S. (1492) Flugblatt, J. von Ople, Basel, 1 p. Izarn J. (1803) Lithologie Atmospherique, Delalain Fils, Paris, 422 pp. Marvin U. B. (1992) Meteoritics 27, 28-72. Newton H. A. (1891) Comptes Rendus Acad. Sci. 113, 234. Muhll Th. von der (1975) Donnerstein von Ensisheim, Birkhauser Verlag, Basel, 42 pp. Schedel H. (1493) Nuremberg Chronicle, A. Korberger, Nuremberg, 299 pp.

  5. Stone comminution correlates with the average peak pressure incident on a stone during shock wave lithotripsy.

    Science.gov (United States)

    Smith, N; Zhong, P

    2012-10-11

    To investigate the roles of lithotripter shock wave (LSW) parameters and cavitation in stone comminution, a series of in vitro fragmentation experiments have been conducted in water and 1,3-butanediol (a cavitation-suppressive fluid) at a variety of acoustic field positions of an electromagnetic shock wave lithotripter. Using field mapping data and integrated parameters averaged over a circular stone holder area (R(h)=7 mm), close logarithmic correlations between the average peak pressure (P(+(avg))) incident on the stone (D=10 mm BegoStone) and comminution efficiency after 500 and 1000 shocks have been identified. Moreover, the correlations have demonstrated distinctive thresholds in P(+(avg)) (5.3 MPa and 7.6 MPa for soft and hard stones, respectively), that are required to initiate stone fragmentation independent of surrounding fluid medium and LSW dose. These observations, should they be confirmed using other shock wave lithotripters, may provide an important field parameter (i.e., P(+(avg))) to guide appropriate application of SWL in clinics, and facilitate device comparison and design improvements in future lithotripters. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Concept for an ultimate storage facility for heat-generating radioactive waste in clay stone in Germany

    International Nuclear Information System (INIS)

    Bollingerfehr, Wilhelm; Poehler, Matthias

    2010-01-01

    According to the German reference ultimate storage concept heat-generating radioactive waste from the operation of nuclear power stations should be stored permanently maintenance-free and in a non-recoverable manner in a salt formation. Within the framework of investigations into the utilisation of alternative host rocks a concept for an ultimate storage facility in clay stone was developed in an R and D project. For this purpose all important aspects of the design, development, operation and shutdown were taken into account for a model region in northern Germany. It was established that storage in 50 m deep vertical boreholes in a mine at a depth of about 350 m appears to be the most practical solution for an ultimate storage facility in clay stone. Compared to the reference concept in salt an ultimate storage facility in clay stone requires solid support of all mine openings with steel arches or shotcrete. Because of the lower maximum permissible temperature in the backfilling material (bentonite) the area required for the ultimate storage facility is about five times larger. A period of more than 100 years is estimated from survey to shutdown. (orig.)

  7. Sarsen Stones of Stonehenge: How and by what route were the stones transported? What is the significance of their markings?

    Science.gov (United States)

    Hill, P A

    1961-04-21

    A route via Lockeridge and the Avon Valley, involving a slide down the chalk escarpment, is postulated for the sarsen stones of Stonehenge. The transportation problem would have been greatly simplified if the stones had been relayed from point to point over snow or slush during successive winters. Markings on the stones hitherto undescribed are interpreted.

  8. The effect of inclined position on stone free rates in patients with lower caliceal stones during SWL session

    Directory of Open Access Journals (Sweden)

    Basri Cakiroglu

    2015-03-01

    Full Text Available Objective: To compare the outcomes of shock wave lithotripsy (SWL combined with inclined position and SWL alone in patients with lower pole calyx stones. Methods: Seven hundred forty patients who underwent SWL treatment for lower pole renal stones with a total diameter of 2 cm or less were prospectively randomized into two groups. They were comparable in terms of age, sex, and stone diameters. Patients with lower calyceal stones (4-20 mm were randomized to SWL (368 patients or SWL with simultaneous inclination (372 patients with 30o head down Trendelenburg position. Shock wave and session numbers were standardized according to stone size. Additional standardized shock waves were given to patients with stone fragments determined by kidney urinary bladder film and ultrasound at weeks 1, 4, 10. Results: The overall stone free rate (SFR was 73% (268/368 in patients with SWL alone and 81% (300/372 in SWL with inclination at the end of 12th week (p = 0.015. No significant adverse events were noted in both treatment groups. Conclusion: Simultaneous inclination of patients during SWL session increase SFR in lower caliceal stones significantly compared to SWL treatment alone.

  9. ORIGINAL PAPER ORIG ORIG Percutaneous stone removal

    African Journals Online (AJOL)

    Percutaneous nephrolithotomy (PCNL) is an effective procedure to treat patients with complex renal stones,. e.g. staghorn calculi and stones greater than 20 mm in diameter. The treatment of choice for small, less com- plex renal stones is extracorporeal shock-wave litho- tripsy (ESWL).1 We have treated renal stones mainly.

  10. Production of lightweight aggregates from washing aggregate sludge and fly ash

    Science.gov (United States)

    González-Corrochano, Beatriz; Alonso-Azcárate, Jacinto; Rodas, Magdalena

    2010-05-01

    manufactured with 75%:25% and 50%:50% proportions of washing aggregate sludge:fly ash, heated at different temperatures and dwell times, were expanded LWAs (BI > 0). They showed the lowest loose bulk density, the lowest dry and apparent particle density, the lowest water absorption and the highest compressive strength. The possible applications of sintered pellets, taking into consideration compressive strength and water absorption values, could be similar to those of Arlita G3 (insulation, geotechnical applications, gardening and/or horticulture) and/or Arlita F3 (prefabricated lightweight structures and insulation lightweight concretes), two varieties of the most widely marketed LWAs in Spain. References - Benbow, J., September 1987. Mineral in fire protection construction support market. Industrial Minerals, 61-73. - Bethanis, S., Cheeseman, C.R., Sollars, C.J., 2004. Effect of sintering temperature on the properties and leaching of incinerator bottom ash. Waste Management and Research 22 (4), 255-264. - De' Gennaro, R., Cappelletti, P., Cerri, G., De' Gennaro, M., Dondi, M., Langella, A., 2004. Zeolitic tuffs as raw materials for lightweight aggregates. Applied Clay Science 25 (1-2), 71-81. - Fakhfakh, E., Hajjaji, W., Medhioub, M., Rocha, F., López-Galindo, A., Setti, M.,Kooli, F., Zargouni, F., Jamoussi, F., 2007. Effects of sand addition on production of lightweight aggregates from Tunisian smectite-rich clayey rocks. Applied Clay Science 35, 228-237. - UNE-EN-13055-1, 2003. Lightweight aggregates - lightweight aggregates for concrete, mortar and grout. - Yasuda, Y., 1991. Sewage-sludge utilization in Tokyo. Water Science and Technology 23 (10-12), 1743-1752.

  11. Characterizing the hypersiliceous rocks of Belgium used in (pre-)history: a case study on sourcing sedimentary quartzites

    International Nuclear Information System (INIS)

    Veldeman, Isis; Baele, Jean-Marc; De Doncker, H W J A; Goemaere, Eric; Deceukelaire, Marleen; Dusar, Michiel

    2012-01-01

    Tracking raw material back to its extraction source is a crucial step for archaeologists when trying to deduce migration patterns and trade contacts in (pre-)history. Regarding stone artefacts, the main rock types encountered in the archaeological record of Belgium are hypersiliceous rocks. This is a newly introduced category of rock types comprising those rocks made of at least 90% silica. These are strongly silicified quartz sands or sedimentary quartzites, siliceous rocks of chemical and biochemical origin (e.g. flint), very pure metamorphic quartzites and siliceous volcanic rocks (e.g. obsidian). To be able to distinguish between different extraction sources, ongoing research was started to locate possible extraction sources of hypersiliceous rocks and to characterize rocks collected from these sources. Characterization of these hypersiliceous rocks is executed with the aid of optical polarizing microscopy, optical cold cathodoluminescence and scanning-electron microscopy combined with energy-dispersive x-ray spectrometry and with back-scatter electron imaging. In this paper, we focus on various sedimentary quartzites of Paleogene stratigraphical level. (paper)

  12. Effect of stone coverage on soil erosion

    Science.gov (United States)

    Jomaa, S.; Barry, D. A.; Heng, B. P.; Brovelli, A.; Sander, G. C.; Parlange, J.

    2010-12-01

    Soil surface coverage has a significant impact on water infiltration, runoff and soil erosion yields. In particular, surface stones protect the soils from raindrop detachment, they retard the overland flow therefore decreasing its sediment transport capacity, and they prevent surface sealing. Several physical and environmental factors control to what extent stones on the soil surface modify the erosion rates and the related hydrological response. Among the most important factors are the moisture content of the topsoil, stone size, emplacement, coverage density and soil texture. Owing to the different inter-related processes, there is ambiguity concerning the quantitative effect of stones, and process-based understanding is limited. Experiments were performed (i) to quantify how stone features affect sediment yields, (ii) to understand the local effect of isolated surface stones, that is, the changes of the soil particle size distribution in the vicinity of a stone and (iii) to determine how stones attenuate the development of surface sealing and in turn how this affects the local infiltration rate. A series of experiments using the EPFL 6-m × 2-m erosion flume were conducted at different rainfall intensities (28 and 74 mm h-1) and stone coverage (20 and 40%). The total sediment concentration, the concentration of the individual size classes and the flow discharge were measured. In order to analyze the measurements, the Hairsine and Rose (HR) erosion model was adapted to account for the shielding effect of the stone cover. This was done by suitably adjusting the parameters based on the area not covered by stones. It was found that the modified HR model predictions agreed well with the measured sediment concentrations especially for the long time behavior. Changes in the bulk density of the topsoil due to raindrop-induced compaction with and without stone protection revealed that the stones protect the upper soil surface against the structural seals resulting in

  13. Nanobacteria: An Infectious Cause for Salivary Stone Formation and Recurrence

    Directory of Open Access Journals (Sweden)

    Amr A El Badry

    2010-01-01

    Full Text Available Nanobacteria (NB contribute to pathological calcification in the human and animal body. It has been isolated from salivary stones and suggested that it may act as a nucleus for the initiation of these stones. In the present study, we examined its role in the recurrent salivary gland stones using immunodetection with NB-specific monoclonal antibodies and scanning electron microscopy (SEM hoping to provide a method for preventing the recurrence of these stones in the patient that has suffered from salivary stones. Our study comprised 30 patients with recurrent salivary gland stones (group I and 30 patients with salivary gland stones for the first time (group II, in addition to 30 normal controls (group III. We could detect 100–500 nm nanoparticles in 24/30 (80% cases in group I with significant difference <0.05 and <0.01 when compared with group II and group III in which they were detected in 19/30 (63.3% and 6/30 (20% respectively. Also there was a significant difference <0.05 between group II and group III. We proposed that salivary stone formation is a nanobacterial disease initiated by bacterial infection. This bacteria may play an important role in the recurrence of salivary stone. So the use of calcium chelator, ethylene diamine tetra acetic acid (EDTA, before or in combination with the suitable antibiotic that is given in an amount effective to inhibit or prevent the growth and development of nanobacteria may eradicate these stones and prevent their recurrence.

  14. Advances in percutaneous stone surgery.

    Science.gov (United States)

    Hartman, Christopher; Gupta, Nikhil; Leavitt, David; Hoenig, David; Okeke, Zeph; Smith, Arthur

    2015-01-01

    Treatment of large renal stones has changed considerably in recent years. The increasing prevalence of nephrolithiasis has mandated that urologists perform more surgeries for large renal calculi than before, and this has been met with improvements in percutaneous stone surgery. In this review paper, we examine recent developments in percutaneous stone surgery, including advances in diagnosis and preoperative planning, renal access, patient position, tract dilation, nephroscopes, lithotripsy, exit strategies, and post-operative antibiotic prophylaxis.

  15. Do Urinary Cystine Parameters Predict Clinical Stone Activity?

    Science.gov (United States)

    Friedlander, Justin I; Antonelli, Jodi A; Canvasser, Noah E; Morgan, Monica S C; Mollengarden, Daniel; Best, Sara; Pearle, Margaret S

    2018-02-01

    An accurate urinary predictor of stone recurrence would be clinically advantageous for patients with cystinuria. A proprietary assay (Litholink, Chicago, Illinois) measures cystine capacity as a potentially more reliable estimate of stone forming propensity. The recommended capacity level to prevent stone formation, which is greater than 150 mg/l, has not been directly correlated with clinical stone activity. We investigated the relationship between urinary cystine parameters and clinical stone activity. We prospectively followed 48 patients with cystinuria using 24-hour urine collections and serial imaging, and recorded stone activity. We compared cystine urinary parameters at times of stone activity with those obtained during periods of stone quiescence. We then performed correlation and ROC analysis to evaluate the performance of cystine parameters to predict stone activity. During a median followup of 70.6 months (range 2.2 to 274.6) 85 stone events occurred which could be linked to a recent urine collection. Cystine capacity was significantly greater for quiescent urine than for stone event urine (mean ± SD 48 ± 107 vs -38 ± 163 mg/l, p stone activity (r = -0.29, p r = -0.88, p r = -0.87, p stone quiescence. Decreasing the cutoff to 90 mg/l or greater improved sensitivity to 25.2% while maintaining specificity at 90.9%. Our results suggest that the target for capacity should be lower than previously advised. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  16. Melting behaviour of raw materials and recycled stone wool waste

    DEFF Research Database (Denmark)

    Schultz-Falk, Vickie; Agersted, Karsten; Jensen, Peter Arendt

    2018-01-01

    Stone wool is a widely used material for building insulation, to provide thermal comfort along with fire stability and acoustic comfort for all types of buildings. Stone wool waste generated either during production or during renovation or demolition of buildings can be recycled back into the sto...... wool melt production. This study investigates and compares the thermal response and melting behaviour of a conventional stone wool charge and stone wool waste. The study combines differential scanning calorimetry (DSC), hot stage microscopy (HSM) and X-ray diffraction (XRD). DSC reveals...... that the conventional charge and stone wool waste have fundamentally different thermal responses, where the charge experiences gas release, phase transition and melting of the individual raw materials. The stone wool waste experiences glass transition, crystallization and finally melting. Both DSC and HSM measurements...

  17. Middle and Later Stone Age chronology of Kisese II rockshelter (UNESCO World Heritage Kondoa Rock-Art Sites), Tanzania.

    Science.gov (United States)

    Tryon, Christian A; Lewis, Jason E; Ranhorn, Kathryn L; Kwekason, Amandus; Alex, Bridget; Laird, Myra F; Marean, Curtis W; Niespolo, Elizabeth; Nivens, Joelle; Mabulla, Audax Z P

    2018-01-01

    The archaeology of East Africa during the last ~65,000 years plays a central role in debates about the origins and dispersal of modern humans, Homo sapiens. Despite the historical importance of the region to these discussions, reliable chronologies for the nature, tempo, and timing of human behavioral changes seen among Middle Stone Age (MSA) and Later Stone Age (LSA) archaeological assemblages are sparse. The Kisese II rockshelter in the Kondoa region of Tanzania, originally excavated in 1956, preserves a ≥ 6-m-thick archaeological succession that spans the MSA/LSA transition, with lithic artifacts such as Levallois and bladelet cores and backed microliths, the recurrent use of red ochre, and >5,000 ostrich eggshell beads and bead fragments. Twenty-nine radiocarbon dates on ostrich eggshell carbonate make Kisese II one of the most robust chronological sequences for understanding archaeological change over the last ~47,000 years in East Africa. In particular, ostrich eggshell beads and backed microliths appear by 46-42 ka cal BP and occur throughout overlying Late Pleistocene and Holocene strata. Changes in lithic technology suggest an MSA/LSA transition that began 39-34.3 ka, with typical LSA technologies in place by the Last Glacial Maximum. The timing of these changes demonstrates the time-transgressive nature of behavioral innovations often linked to the origins of modern humans, even within a single region of Africa.

  18. Modeling Stone Columns.

    Science.gov (United States)

    Castro, Jorge

    2017-07-11

    This paper reviews the main modeling techniques for stone columns, both ordinary stone columns and geosynthetic-encased stone columns. The paper tries to encompass the more recent advances and recommendations in the topic. Regarding the geometrical model, the main options are the "unit cell", longitudinal gravel trenches in plane strain conditions, cylindrical rings of gravel in axial symmetry conditions, equivalent homogeneous soil with improved properties and three-dimensional models, either a full three-dimensional model or just a three-dimensional row or slice of columns. Some guidelines for obtaining these simplified geometrical models are provided and the particular case of groups of columns under footings is also analyzed. For the latter case, there is a column critical length that is around twice the footing width for non-encased columns in a homogeneous soft soil. In the literature, the column critical length is sometimes given as a function of the column length, which leads to some disparities in its value. Here it is shown that the column critical length mainly depends on the footing dimensions. Some other features related with column modeling are also briefly presented, such as the influence of column installation. Finally, some guidance and recommendations are provided on parameter selection for the study of stone columns.

  19. Evolution of stone management in Australia.

    Science.gov (United States)

    Lee, Ming-Chak; Bariol, Simon Virgil

    2011-11-01

    What's known on the subject? and What does the study add? There is very little contemporary data regarding stone management in Australia. This study assesses the impact of technological advances on stone management practises, and raises questions as to why there is an increasing rate of intervention for stone disease in Australia. Knowledge of management trends as demonstrated in this paper give individual surgeons a guideline for contemporary practise in this country. • To examine trends in the operative management of upper urinary tract stone disease in Australia over the past 15 years. • The Medicare Australia and Australian Institute of Health and Welfare databases were used to determine the annual number of renal colic presentations and procedural interventions undertaken for stone disease. • In Australia over the past 15 years, the annual number of procedural interventions for upper urinary tract stones has increased, primarily due to the rising number of endoscopic procedures performed. • During this period, shock wave lithotripsy numbers have remained steady whilst open and percutaneous procedures have been in decline. • The introduction of and subsequent preference for less invasive techniques has changed the management pathway of patients presenting with stone disease in Australia. • Further studies are necessary to determine whether this escalation in endoscopic procedures is due to an increase in the incidence of stone disease, earlier detection, a lower intervention threshold or a higher retreatment rate. © 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.

  20. Effect of Stone Size and Composition on Ultrasonic Propulsion Ex Vivo.

    Science.gov (United States)

    Janssen, Karmon M; Brand, Timothy C; Bailey, Michael R; Cunitz, Bryan W; Harper, Jonathan D; Sorensen, Mathew D; Dunmire, Barbrina

    2018-01-01

    To evaluate in more detail the effectiveness of a new designed more efficient ultrasonic propulsion for large stones and specific stone compositions in a tissue phantom model. In the first clinical trial of noninvasive ultrasonic propulsion, urinary stones of unknown compositions and sizes up to 10 mm were successfully repositioned. The study included 8- to 12-mm stones of 4 different primary compositions (calcium oxalate monohydrate, ammonium acid urate, calcium phosphate, and struvite) and a renal calyx phantom consisting of a 12 mm × 30 mm well in a 10-cm block of tissue-mimicking material. Primary outcome was the number of times a stone was expelled over 10 attempts, with ultrasonic propulsion burst duration varying from 0.5 seconds to 5 seconds. Overall success rate at expelling stones was 95%. All calcium oxalate monohydrate and ammonium acid urate stones were expelled 100% of the time. The largest stone (12 mm) became lodged within the 12-mm phantom calyx 25% of the time regardless of the burst duration. With the 0.5-second burst, there was insufficient energy to expel the heaviest stone (0.88 g), but there was sufficient energy at the longer burst durations. With a single burst, ultrasonic propulsion successfully moved most stones at least 3 cm and, regardless of size or composition, expelled them from the calyx. Ultrasonic propulsion is limited to the stones smaller than the calyceal space, and for each burst duration, related to maximum stone mass. Published by Elsevier Inc.

  1. Intraperitoneal stone migration during percutaneos nephrolithotomy

    Directory of Open Access Journals (Sweden)

    Akif Diri

    2014-12-01

    Full Text Available Percutaneos nephrolithotomy (PNL is the standard care for renal stones larger than 2 cm. The procedure has some major and minor complications. Renal pelvis laceration and stone migration to the retroperitoneum is one of the rare condition. We report the first case of intraperitoneal stone migration during PNL.

  2. Stone stability under non-uniform flow

    NARCIS (Netherlands)

    Hoan, N.T.

    2008-01-01

    Despite the fact that many studies on the stability of stones in bed protections under flowing water have been conducted, our knowledge is still far from advanced and reliable. Issues like how to quantify the hydraulic loads exerted on the stones on a bed and the associated stability of the stones

  3. Thermoluminescence of pyramid stones

    International Nuclear Information System (INIS)

    Gomaa, M.A.; Eid, A.M.

    1982-01-01

    It is the aim of the present study to investigate some thermoluminescence properties of pyramid stones. Using a few grammes of pyramid stones from Pyramids I and II, the TL glow peaks were observed at 250 and 310 0 C, respectively. The TL glow peaks of samples annealed at 600 0 C, then exposed to 60 Co γ-rays were observed at 120, 190 and 310 0 C, respectively. The accumulated dose of natural samples is estimated to be around 310 Gray (31 krad). By assuming an annual dose is 1 mGy, the estimated age of pyramid stones is 0.31 M year. (author)

  4. Thermoluminescence of pyramid stones

    Energy Technology Data Exchange (ETDEWEB)

    Gomaa, M A; Eid, A M [Atomic Energy Establishment, Cairo (Egypt)

    1982-01-01

    It is the aim of the present study to investigate some thermoluminescence properties of pyramid stones. Using a few grammes of pyramid stones from Pyramids I and II, the TL glow peaks were observed at 250 and 310/sup 0/C, respectively. The TL glow peaks of samples annealed at 600/sup 0/C, then exposed to /sup 60/Co ..gamma..-rays were observed at 120, 190 and 310/sup 0/C, respectively. The accumulated dose of natural samples is estimated to be around 310 Gray (31 krad). By assuming an annual dose is 1 mGy, the estimated age of pyramid stones is 0.31 M year.

  5. Prediction of Exploration Target Areas for GEM Deposits in Mogok Stone Tract, Northern Myanmar by Integrating Remote Sensing and Geoscience Data

    Science.gov (United States)

    Oo, Tin Ko

    2011-07-01

    The Mogok Stone Tract area has long been known for world famous finest ruby since 1597. The Mogok area lies in northern Myanmar and is located at about 205.99km northeast from Mandalay, the second largest city of Myanmar. The Mogok Group of metasedimentary rocks is divided into four units: (1) Wabyudaung Marble, (2) Ayenyeinchantha Calc-silicate, (3) Gwebin Quartzite, and (4) Kabe Gneiss. Igneous rocks in the Mogok area are classified into two units: (1) Kabaing Granite and (2) Pingutaung Leucogranite. The Mogok area has a complex structure involving several folds and faults. Using marbles and calc-silicates as marker horizons, a series of anticline and syncline can be identified such as Mogok syncline, Ongaing anticline, Bawpadan syncline, and Kyatpyin anticline. All the foldings show a low-angle plunge to the south. The main precious stones of the Mogok area are ruby and sapphire; and the other important semi-precious stones are spinel, topaz, peridot, garnet, apatite, beryl, tourmaline (rubellite), quartz, diopside, fluorite, and enstatite. Geological and remote sensing data are processed to extract the indicative features of gem mineralized areas: lithology, structure, and hydrothermal alteration. Density slice version of Landsat ETM band ratios 5/7 is used to map clay alterations. Filtering Landsat ETM band 5 by using edge detection filter is applied for lineament mapping. Spatial integration of various geoscience and remote sensing data sets such as geological maps, Landsat ETM images, and the location map of gem mines show the distribution of alteration zones associated with the gem mineralization in the study area. Geographic Information System (GIS) model has been designed and implemented by ARCVIEW software package based on the overlay of lithologic, lineament, and alteration vector maps. This process has resulted in delineation of most promising areas of probable gem mineralized zones as on the output map.

  6. Assesment of Alkali Resistance of Basalt Used as Concrete Aggregates

    Directory of Open Access Journals (Sweden)

    al-Swaidani Aref M.

    2015-11-01

    Full Text Available The objective of this paper is to report a part of an ongoing research on the influence of using crushed basalt as aggregates on one of durability-related properties of concrete (i.e. alkali-silica reaction which is the most common form of Alkali-Aggregate Reaction. Alkali resistance has been assessed through several methods specified in the American Standards. Results of petrographic examination, chemical test (ASTM C289 and accelerated mortar bar test (ASTM C1260 have particularly been reported. In addition, the weight change and compressive strength of 28 days cured concrete containing basaltic aggregates were also reported after 90 days of exposure to 10% NaOH solution. Dolomite aggregate were used in the latter test for comparison. The experimental results revealed that basaltic rocks quarried from As-Swaida’a region were suitable for production of aggregates for concrete. According to the test results, the studied basalt aggregates can be classified as innocuous with regard to alkali-silica reaction. Further, the 10% sodium hydroxide attack did not affect the compressive strength of concrete.

  7. A Boy with a Large Bladder Stone

    Directory of Open Access Journals (Sweden)

    Kuo-Shen Chow

    2008-08-01

    Full Text Available Despite the frequent association of urinary tract infection with vesicoureteral reflux and urinary calculi, since vesicouretal reflux is induced by bladder stones, the coexistence of vesicoureteral reflux and bladder stones is rare. Because of its occurrence in children belonging to poor socioeconomic groups, it is believed to be a deficiency disorder. Most cases of bladder stones occur between the ages of 2 and 5 years. Common clinical presentations of bladder stones include urinary dribbling and enuresis, frequency of micturition, pain during micturition, pelvic pain and hematuria. We report the occurrence of a large bladder stone in a boy, who experienced intermittent lower abdominal pain and urinary incontinence, both during the day and at night. He had been diagnosed with enuresis and treated in pediatric clinics for 1 year. Delayed diagnosis resulted in bladder stone formation. The stone was larger than 2.5 cm and open vesicolithotomy was therefore selected as the best and safest treatment choice. His symptoms disappeared after surgery. Thorough metabolic and environmental evaluations of such cases are required on an individual basis. Bladder stones should be considered as a possible diagnosis in children presenting with urinary incontinence.

  8. Algorithm for definition of stones components at kidney-stones illness using two-energetic digital roentgen-graphic method

    International Nuclear Information System (INIS)

    Nedavnij, O.I.; Osipov, S.P.

    2001-01-01

    Paper presents the algorithm for definition of stone composition in case of kidney-stones using two-energy digital X-ray photography. One calculated the values of p information parameter for the main types of stones within 40-150 keV energy range. It was shown that p parameter dependence on energy was not essential one (maximum 3.5% deviation), p value for various chemical compositions of kidney stones ranged from 15% (calcium phosphate and calcium oxalate) up to 70% (calcium lactate and calcium oxalate). The conducted studies enable to make a conclusion about the possibility to define material representing the heart of kidney stones using two-energy digital X-ray photography. Paper includes recommendations on selection of the optimal energy values [ru

  9. A new method for controlling of floor heave of deep tunnels in soft rocks by mini-tube grouting piles of crushed stones%微型碎石管注桩治理深部软岩巷道底鼓新方法

    Institute of Scientific and Technical Information of China (English)

    谢芳; 王金安

    2013-01-01

    针对造成巷道底鼓的物理和力学两种重要机制,研究并提出微型碎石管注桩治理深部软岩巷道底鼓的新方法.在物理机制方面,微型碎石桩具有渗透性极好的特点,在巷道施工和使用期间可汲取岩体中的渗水并透过碎石桩中的插管排出,从而降低软岩层因遇水膨胀导致的变形;在力学机制方面,微型碎石桩一方面通过钻孔置换出少部分底板软岩,从体量上减少变形岩体,另一方面能利用碎石桩体的侧向可压缩性耗散岩体水平变形,底板岩层中的水平地应力得以释放,极大减缓了促使底鼓变形的力学作用;通过微型碎石桩中的插管注浆加固底板岩体,提高了底板复合地基整体承载力.通过数值分析,阐明该方法在治理软岩巷道底鼓机制上的有效性.%Focusing on two important mechanisms of physics and mechanics that give rise to the floor heave of tunnels , a new method of controlling the floor heave of deep tunnels in soft rocks was proposed by means of mini-tube grouting piles of crushed stones. In physical aspect, the method utilizes the characteristics of good permeability of crushed stone pile to absorb the water in rockmass and drainage out through the tubes in the pile during the construction and application of the tunnels, resulting in the decrease in expansion deformation of soft rock due to water saturation. In mechanical aspect, partial volume in floor stratum has been replaced, on one hand, by the installed mini piles which reduce the volume of the deforming rock body, and on the other hand, amount of horizontal deformation are dissipated through the lateral compressive deformation of the crushed stone pile, and the horizontal stress is released. As a result, the mechanical affect that induces the heave deformation in floor stratum is considerably reduced. By means of grouting the crushed stones through the tube inserted in the pile, the floor stratum is reinforced and the

  10. Journey of a cystinuric patient with a long-term follow-up from a medical stone clinic: necessity to be SaFER (stone and fragments entirely removed).

    Science.gov (United States)

    Moore, Sacha L; Somani, Bhaskar K; Cook, Paul

    2018-04-25

    There is a lack of studies looking at the longitudinal follow-up of patients with cystine stones. We wanted to assess the journey of cystinuric patients through our specialist metabolic stone clinic to improve the understanding of episodes, interventions and current outcomes in this patient cohort. After ethical approval, all patients who attended our metabolic stone clinic from 1994 to 2014 with at least one cystine stone episode were included in our study. Data were retrospectively analysed for patient demographics, stone episodes or intervention, clinical parameters and patient compliance. Over a period of 21 years, 16 patients with a median age of 15.5 years underwent a mean follow-up of 8.6 years (1-21 years). The mean number of surgical interventions was 3.1 (1-8/patient), but patients who were stone free after their first treatment had lower recurrences (p = 0.91) and lower number of interventions during their follow-up (2.7/patient, compared to those who were not stone free at 4/patient). During their follow-up period, patients with stone episodes (r 2  = 0.169). It was also noted that patients who began early medical management remained stone free during follow-up compared to those who had medical management after ≥ 2 stone episodes, of whom all had a recurrent episode. Our long-term longitudinal study of cystine stone formers highlights that patients who are stone free and receive early metabolic stone screening and medical management after their initial presentation have the lowest recurrence rates and tend to preserve their renal function. Hence, prompt referral for metabolic assessment, and the stone and fragments entirely removed (SaFER) principles are key to preventing stone episodes and improving long-term function.

  11. Occasional, obligatory, and habitual stone tool use in hominin evolution.

    Science.gov (United States)

    Shea, John J

    2017-09-01

    Archeologists have long assumed that earlier hominins were obligatory stone tool users. This assumption is deeply embedded in traditional ways of describing the lithic record. This paper argues that lithic evidence dating before 1.7 Ma reflects occasional stone tool use, much like that practiced by nonhuman primates except that it involved flaked-stone cutting tools. Evidence younger than 0.3 Ma is more congruent with obligatory stone tool use, like that among recent humans. The onset of habitual stone tool use at about 1.7 Ma appears correlated with increased hominin logistical mobility (carrying things). The onset of obligatory stone tool use after 0.3 Ma may be linked to the evolution of spoken language. Viewing the lithic evidence dating between 0.3-1.7 Ma as habitual stone tool use explains previously inexplicable aspects of the Early-Middle Pleistocene lithic record. © 2017 Wiley Periodicals, Inc.

  12. Female stone disease: the changing trend.

    Science.gov (United States)

    Marickar, Y M Fazil; Vijay, Adarsh

    2009-12-01

    This paper has attempted to assess the changes noted in the trends in the incidence and biochemical pattern of female urolithiasis patients during the period 1971-2008. A prospective descriptive clinical study was done on 8,590 stone patients belonging to both sexes treated at the urinary stone clinic. The incidence of stone disease among the two sexes was plotted. The various metabolic parameters including 24-h urine volume, urine calcium, phosphorus, uric acid, oxalate, magnesium, creatinine and citrate, serum creatinine, calcium, phosphorus, uric acid and magnesium and calculated parameter calcium:magnesium ratio were studied. The possible causes for the change in incidence of stone disease in the female sex were elucidated. Of the patients studied, 12.7% (1,091) were females. There was a definite increase in the incidence of female urolithiasis over the past 37 years (P stone genesis, together with the increased excretion of calcium and oxalate may have contributed to the increasing incidence of stone disease in females. This might be due to changes in living standards and dietary habits.

  13. The Civil Palaces in Gravina street, Alicante: building stones and salt weathering

    OpenAIRE

    Louis, M.; García del Cura, M. A.; Spairani, Y.; de Blas, D.

    2001-01-01

    This paper presents a study into the architecture and construction of the 18th Century Civil Palaces located in Gravina street (Provincial Museum of Fine Arts of Alicante), the building stones used and the mineral related decay processes that these materials have suffered. The original building stones and other stones used in subsequent restorations in these Civil Palaces are bioclastic limestones and/or calcarenites (San Julian Stone and Bateig Stone). Campello stone and other limestones ...

  14. Prediction of Fracture Behavior in Rock and Rock-like Materials Using Discrete Element Models

    Science.gov (United States)

    Katsaga, T.; Young, P.

    2009-05-01

    The study of fracture initiation and propagation in heterogeneous materials such as rock and rock-like materials are of principal interest in the field of rock mechanics and rock engineering. It is crucial to study and investigate failure prediction and safety measures in civil and mining structures. Our work offers a practical approach to predict fracture behaviour using discrete element models. In this approach, the microstructures of materials are presented through the combination of clusters of bonded particles with different inter-cluster particle and bond properties, and intra-cluster bond properties. The geometry of clusters is transferred from information available from thin sections, computed tomography (CT) images and other visual presentation of the modeled material using customized AutoCAD built-in dialog- based Visual Basic Application. Exact microstructures of the tested sample, including fractures, faults, inclusions and void spaces can be duplicated in the discrete element models. Although the microstructural fabrics of rocks and rock-like structures may have different scale, fracture formation and propagation through these materials are alike and will follow similar mechanics. Synthetic material provides an excellent condition for validating the modelling approaches, as fracture behaviours are known with the well-defined composite's properties. Calibration of the macro-properties of matrix material and inclusions (aggregates), were followed with the overall mechanical material responses calibration by adjusting the interfacial properties. The discrete element model predicted similar fracture propagation features and path as that of the real sample material. The path of the fractures and matrix-inclusion interaction was compared using computed tomography images. Initiation and fracture formation in the model and real material were compared using Acoustic Emission data. Analysing the temporal and spatial evolution of AE events, collected during the

  15. A sampling study on rock properties affecting drilling rate index (DRI)

    Science.gov (United States)

    Yenice, Hayati; Özdoğan, Mehmet V.; Özfırat, M. Kemal

    2018-05-01

    Drilling rate index (DRI) developed in Norway is a very useful index in determining the drillability of rocks and even in performance prediction of hard rock TBMs and it requires special laboratory test equipment. Drillability is one of the most important subjects in rock excavation. However, determining drillability index from physical and mechanical properties of rocks is very important for practicing engineers such as underground excavation, drilling operations in open pit mining, underground mining and natural stone production. That is why many researchers have studied concerned with drillability to find the correlations between drilling rate index (DRI) and penetration rate, influence of geological properties on drillability prediction in tunneling, correlations between rock properties and drillability. In this study, the relationships between drilling rate index (DRI) and some physico-mechanical properties (Density, Shore hardness, uniaxial compressive strength (UCS, σc), Indirect tensile strength (ITS, σt)) of three different rock groups including magmatic, sedimentary and metamorphic were evaluated using both simple and multiple regression analysis. This study reveals the effects of rock properties on DRI according to different types of rocks. In simple regression, quite high correlations were found between DRI and uniaxial compressive strength (UCS) and also between DRI and indirect tensile strength (ITS) values. Multiple regression analyses revealed even higher correlations when compared to simple regression. Especially, UCS, ITS, Shore hardness (SH) and the interactions between them were found to be very effective on DRI values.

  16. Percutaneous nephrolithotomy for the treatment of radiolucent renal stones in children: is it different opaque stone treatment?

    Science.gov (United States)

    Adanur, Şenol; Ziypak, Tevfik; Sancaktutar, Ahmet Ali; Tepeler, Abdülkadir; Reşorlu, Berkan; Söylemez, Haluk; Dağgülli, Mansur; Özbey, İsa; Unsal, Ali

    2014-02-01

    We aimed to evaluate the effectiveness of percutaneous nephrolithotomy (PNL), stone-free rates, and related complications in children with radiolucent renal stones. A total of 56 patients aged auxillary treatment method was detected as 94.6%. The total complication rate was 19.6% (11 patients). No adjacent organ injury was observed. All of the complications that occurred were minor according to the Clavien classification (Clavien Grades I-II). PNL can be applied to radiolucent pediatric renal stones in children with similar success, and complication rates as noted for radiopaque stones.

  17. Pattern of family history in stone patients.

    Science.gov (United States)

    Marickar, Y M Fazil; Salim, Abiya; Vijay, Adarsh

    2009-12-01

    Genetic predisposition to urolithiasis is a much discussed topic. The objective of this paper is to identify the types of family members of proved urinary stone patients, who have a history of urinary stone formation. The study population consisted of 2,157 urinary stone patients interviewed in 2003-2007 in the urinary stone clinic. Family members with stone history were classified as group 1--first order single (one person in the immediate family-father, mother, siblings, or children), group 2--first order multiple (more than one member in the above group), group 3--second order single (one person in the blood relatives in family--grandparents, grandchildren, uncles, aunts, cousins, etc.) and group 4--second order multiple (more than one member in the above group). Of the 2,157 patients studied, 349 patients gave positive history of stone disease constituting 16.18%. Of these, 321 were males and 28 were females. Subdivision of the family members showed that 282 patients (80.80%) had single family member with stones and the rest 67 (19.20%) had multiple family members with history of stone disease. Group 1 which constituted one family member in the immediate family had 255 involvements (father: 88, mother: 16, brother: 135, sister: 2, son: 10, and daughter: 4); Group 2 with multiple members in the immediate family constituted 51 relatives; of these, father and brother combination was the most common with 35 occurrences. Group 3 with one person in the distant relatives in family namely grandparents, grand children, uncles, aunts, cousins, etc. constituted 27 occurrences and Group 4 with more than one member in the distant family constituted 16 occurrences. It is concluded that single family member involvement was more than multiple involvements. Males predominated. Stone occurrence was more in the immediate family members than distant relatives. Brothers formed the most common group to be involved with stone disease. Study of stone risk in the family members should

  18. Morulustatin, A Disintegrin that Inhibits ADP-Induced Platelet Aggregation, Isolated from the Mexican Tamaulipan Rock Rattlesnake (Crotalus lepidus morulus)

    Science.gov (United States)

    Borja, Miguel; Galan, Jacob Anthony; Cantu, Esteban; Zugasti-Cruz, Alejandro; Rodríguez-Acosta, Alexis; Lazcano, David; Lucena, Sara; Suntravat, Montamas; Sánchez, y Elda Eliza

    2016-01-01

    The Tamaulipan rock rattlesnake (Crotalus lepidus morulus) is a montane snake that occurs in the humid pine-oak forest and the upper cloud forest of the Sierra Madre Oriental in southwestern Tamaulipas, central Nuevo Leon, and southeastern Coahuila in Mexico. Venom from this rattlesnake was fractionated by High-Performance Liquid Chromatography for the purpose of discovering disintegrin molecules. Disintegrins are non-enzymatic, small molecular weight peptides that interfere with cell-cell and cell-matrix interactions by binding to various cell receptors. Eleven fractions were collected by anion exchange chromatography and pooled into six groups (I, II, III, IV, V, and VI). Proteins of the six groups were analyzed by SDS-PAGE and western blot using antibodies raised against a disintegrin. The antibodies recognized different protein bands in five (II, III, IV, V, and VI) of six groups in a molecular mass range of 7 to 105 kDa. Western blot analysis revealed fewer protein bands in the higher molecular mass range and two bands in the disintegrin weight range in group II compared with the other four groups. Proteins in group II were further separated into nine fractions using reverse phase C18 chromatography. Fraction 4 inhibited platelet aggregation and was named morulustatin, which exhibited a single band with a molecular mass of approximately 7 kDa. Mass spectrometry analysis of fraction 4 revealed the identification of disintegrin peptides LRPGAQCADGLCCDQCR (MH+ 2035.84) and AGEECDCGSPANCCDAATCK (MH+ 2328.82). Morulustatin inhibited ADP-induced platelet aggregation in human whole blood and was concentration-dependent with an IC50 of 89.5 nM ± 12. PMID:28713196

  19. The development of a technological complex in deposits of dimension facing stone

    Directory of Open Access Journals (Sweden)

    Filipova N.P.

    2016-12-01

    Full Text Available One of the main problems in the Ukrainian dimension stone sector is the distribution problem. A typical quarry exploits up to 1000–1500 m3/y of trade blocks. Thus, it is very difficult to perform a standard foreign order of 500-1000 m3. This is often due to improper exploitation technique planning and management. The aim of the study is to identify the best exploitation technique for the Ukrainian shield conditions in terms of the highest technical and economic applicability. The data were collected at several Ukrainian and Italian quarries. Performance data of dimension stone exploitation techniques was measured in order to determine which of them are the most economic and the least labour-intensive. Unit costs for the monolith explosive separation (using detonating cord are more than 3 times lower than the use of the combination of diamond wire sawing and dynamic splitting in terms of 1 m3 of trade blocks. The combination of diamond wire saw with «hydrorocksplitters» is slightly cheaper; it justifies its widespread use in Ukrainian quarries. To preserve the rock mass integrity and block surface quality all of the techniques are suitable. Among the tipping techniques the use of wheel loaders is disseminating nowadays. Hydraulic jacks are used at this stage sometimes. Block separation on trade units is often carried out by splitting with manual or hydraulic wedges. Expensive rock blocks can be also splitted by a diamond wire saw. A wheel loader can be used for block handling under short trips condition. While long trip the use of dump trucks for block and waste products transportation is required.

  20. Natural Stone in Spain: trends and perspectives

    International Nuclear Information System (INIS)

    Marchán Sanz, C.; Regueiro y González-Barros, M.; Delgado Arenas, P.

    2017-01-01

    The natural stone sector was severely affected by the national construction sector crisis. Production, both exworks and processed, has been also harshly affected dropping from 8Mt/y in 2007 to 3,49Mt/y in 2015, particularly in the marble and granite sectors, since slate has always been a mainly exporting sub-sector. In the latest times, thanks mainly to exports, production apparently has slowly started to recover. In this paper, we review the typology of the Spanish natural stone products and the production data of the main stone subsectors (marble, granite and slate) in the last 10 years and we review possible future trends in the framework of the first steps of the economic recovery. [es

  1. Extracorporeal shock-wave lithotripsy of bile duct stones

    International Nuclear Information System (INIS)

    Lee, Jong Tae; Kim, Myung Joon; Yoo, Hyung Sik; Suh, Jung Ho; Lee, Moo Sang; Jo, Jang Hwan; Kim, Byung Ro

    1989-01-01

    During the past one and half year, we performed ESWL therapy in 13 patients with common bile duct and intrahepatic duct stones, applying Lithostar-R (Siemens co. West Germany) and analyzed their results. In 13 patients, 9 residual common bile duct stones and 7 intrahepatic duct stones were selected postoperatively. The size of stones were ranged from 0.7 cm to 3.5 cm in diameter. 2 stones were multiple and the remained 14 were single in number. The visualization of stones were done with fluoroscopy after the injection of contrast media via cholangiographic T-tube or ERCP. ESWL were applied continuously until stone disintegration was visible, or upto maximum number of 3500 discharge of shock wave. If not disintegrated upto 3500, patients were underwent second or third lithotripsy session with interval of one week. Our results showed that among 9 common bile duct stones, 4 were completely disintegrated and passed out spontaneously, but 3 partially fragmented and removed by the additional procedure. 2 were failed. Among 7 intrahepatic stones, 3 completely and 2 partially were succeeded. One stone partially fragmented were retained without removal and other one were failed. Skin petechia in all patients were revealed on the entry port of shock wave, but no serous complication was not occurred

  2. Extracorporeal shock-wave lithotripsy of bile duct stones

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Tae; Kim, Myung Joon; Yoo, Hyung Sik; Suh, Jung Ho; Lee, Moo Sang; Jo, Jang Hwan; Kim, Byung Ro [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1989-12-15

    During the past one and half year, we performed ESWL therapy in 13 patients with common bile duct and intrahepatic duct stones, applying Lithostar-R (Siemens co. West Germany) and analyzed their results. In 13 patients, 9 residual common bile duct stones and 7 intrahepatic duct stones were selected postoperatively. The size of stones were ranged from 0.7 cm to 3.5 cm in diameter. 2 stones were multiple and the remained 14 were single in number. The visualization of stones were done with fluoroscopy after the injection of contrast media via cholangiographic T-tube or ERCP. ESWL were applied continuously until stone disintegration was visible, or upto maximum number of 3500 discharge of shock wave. If not disintegrated upto 3500, patients were underwent second or third lithotripsy session with interval of one week. Our results showed that among 9 common bile duct stones, 4 were completely disintegrated and passed out spontaneously, but 3 partially fragmented and removed by the additional procedure. 2 were failed. Among 7 intrahepatic stones, 3 completely and 2 partially were succeeded. One stone partially fragmented were retained without removal and other one were failed. Skin petechia in all patients were revealed on the entry port of shock wave, but no serous complication was not occurred.

  3. Ureteroscopy and stone lithotripsy with lithoclast: personal experience.

    Science.gov (United States)

    Leidi, G L; Berti, G L; Canclini, L; Giola, V; Maccaroni, A; Raimoldi, A; Veneroni, L; Bacchioni, A M

    1997-06-01

    Ureteroscopy has become a common technique in the diagnosis and treatment of ureteral pathologies, but this procedure is quite invasive and some complications have been reported in literature. In our Institute 49 patients underwent ureteroscopy and ballistic lithotripsy with lithoclast for ureteral stones. The stones were localized both in the middle and distal part of the ureter. We used a small caliber 7-8.5 Wolf ureteroscope. The treatments were performed under antibiotic prophylaxis. Direct access to the ureter without dilation of the meatus was obtained in 97.96% of patients. The stones were easily reached in 93.88% of the cases and satisfactory fragmentation was obtained in 90.7%. In 4 patients (9.3%) one or more large stone fragments escaped into the kidney, requiring the patients to be treated with ESWL. No major complications occurred: no ureteral perforations, no important bleeding and no severe or persistent infections. All patients were discharged in one to four days postoperatively. The authors conclude that ureteroscopy using small caliber instruments with Lithoclast is a safe and satisfactory alternative to ESWL in the treatment of ureteral stones.

  4. The twelve colourful stones

    International Nuclear Information System (INIS)

    Doria, R.M.

    1983-01-01

    A dynamics with twelve colourful stones is created based on the concepts of gauge and colour. It is associated different gauge fields to the same group. A group of gauge invariant Lagrangians is established. A gauge invariant mass term is introduced. The colourful stones physical insight is to be building blocks for quarks and leptons. (Author) [pt

  5. Middle and Later Stone Age chronology of Kisese II rockshelter (UNESCO World Heritage Kondoa Rock-Art Sites), Tanzania

    Science.gov (United States)

    Ranhorn, Kathryn L.; Kwekason, Amandus; Alex, Bridget; Laird, Myra F.; Marean, Curtis W.; Niespolo, Elizabeth; Nivens, Joelle; Mabulla, Audax Z. P.

    2018-01-01

    The archaeology of East Africa during the last ~65,000 years plays a central role in debates about the origins and dispersal of modern humans, Homo sapiens. Despite the historical importance of the region to these discussions, reliable chronologies for the nature, tempo, and timing of human behavioral changes seen among Middle Stone Age (MSA) and Later Stone Age (LSA) archaeological assemblages are sparse. The Kisese II rockshelter in the Kondoa region of Tanzania, originally excavated in 1956, preserves a ≥ 6-m-thick archaeological succession that spans the MSA/LSA transition, with lithic artifacts such as Levallois and bladelet cores and backed microliths, the recurrent use of red ochre, and >5,000 ostrich eggshell beads and bead fragments. Twenty-nine radiocarbon dates on ostrich eggshell carbonate make Kisese II one of the most robust chronological sequences for understanding archaeological change over the last ~47,000 years in East Africa. In particular, ostrich eggshell beads and backed microliths appear by 46–42 ka cal BP and occur throughout overlying Late Pleistocene and Holocene strata. Changes in lithic technology suggest an MSA/LSA transition that began 39–34.3 ka, with typical LSA technologies in place by the Last Glacial Maximum. The timing of these changes demonstrates the time-transgressive nature of behavioral innovations often linked to the origins of modern humans, even within a single region of Africa. PMID:29489827

  6. Piezoelectric extracorporeal lithotripsy of gallbladder stones: New inclusion criteria

    Energy Technology Data Exchange (ETDEWEB)

    Han, Joon Koo; Choi, Byung Ihn; Shin, Yong Moon; Yoon, Yong Kyu; Yoon, Yong Bum; Park, Yong Hyun; Kim, Chu Wan; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1994-08-15

    To establish the optimal inclusion criteria for the patients with gallbladder stones to extracorporeal shock wave lithotripsy(ESWL) by retrospectively analyzed our current results. Data obtained from 201 patients with gallbladder stones treated with ESWL and oral chemolytic agent from November 1988 to July 1992 were retrospectively analyzed. Ninety-six had radiolucent stones and 105 had radiopaque stones. We used piezoelectric lithotriptor(EDAP LT. 01) and there were no limitation in number of sessions or total number of shock waves. ESWL was repeated until the size of the largest fragment is smaller than 4 mm. Follow up ultrasound was done in every three months after the successful fragmentation. Average length of the follow up was 205 days. We analyzed the rate of successful fragmentation, number of shock waves needed to achieve successful fragmentation according to the size, number of stones as well as the presence of the calcification. Stone-free rate after 6 months was also calculated from all subgroups and compared to each other. The rate of successful fragmentation was 76.2% for radiolucent stones and 65.6% for radiopaque stones(p> 0.05) after 46,731 and 56,111 shock wave respectively(p > 0.05) The rate of successful fragmentation was highest in patients with single, radiolucent stone smaller than 2 cm(91.7%) followed by single radiolucent stone larger than 2 cm(83.3%), multiple calcified stones smaller than 2 cm (77.4%) and single calcified stone smaller than 2 cm(72.1%). The rate of complete stone clearance after 6 month follow-up was highest in patients with single radiolucent stone smaller than 2 cm (63.3%) and followed by multiple calcified stones smaller than 2 cm(37.3%), single calcified stone smaller than 2 cm(33.9%)(p < 0.05). To obtain better results with ESWL in patients with gallbladder stone, the authors propose a more strict inclusion criteria, which is the patient with a single, radiolucent stone smaller than 2 cm.

  7. Piezoelectric extracorporeal lithotripsy of gallbladder stones: New inclusion criteria

    International Nuclear Information System (INIS)

    Han, Joon Koo; Choi, Byung Ihn; Shin, Yong Moon; Yoon, Yong Kyu; Yoon, Yong Bum; Park, Yong Hyun; Kim, Chu Wan; Han, Man Chung

    1994-01-01

    To establish the optimal inclusion criteria for the patients with gallbladder stones to extracorporeal shock wave lithotripsy(ESWL) by retrospectively analyzed our current results. Data obtained from 201 patients with gallbladder stones treated with ESWL and oral chemolytic agent from November 1988 to July 1992 were retrospectively analyzed. Ninety-six had radiolucent stones and 105 had radiopaque stones. We used piezoelectric lithotriptor(EDAP LT. 01) and there were no limitation in number of sessions or total number of shock waves. ESWL was repeated until the size of the largest fragment is smaller than 4 mm. Follow up ultrasound was done in every three months after the successful fragmentation. Average length of the follow up was 205 days. We analyzed the rate of successful fragmentation, number of shock waves needed to achieve successful fragmentation according to the size, number of stones as well as the presence of the calcification. Stone-free rate after 6 months was also calculated from all subgroups and compared to each other. The rate of successful fragmentation was 76.2% for radiolucent stones and 65.6% for radiopaque stones(p> 0.05) after 46,731 and 56,111 shock wave respectively(p > 0.05) The rate of successful fragmentation was highest in patients with single, radiolucent stone smaller than 2 cm(91.7%) followed by single radiolucent stone larger than 2 cm(83.3%), multiple calcified stones smaller than 2 cm (77.4%) and single calcified stone smaller than 2 cm(72.1%). The rate of complete stone clearance after 6 month follow-up was highest in patients with single radiolucent stone smaller than 2 cm (63.3%) and followed by multiple calcified stones smaller than 2 cm(37.3%), single calcified stone smaller than 2 cm(33.9%)(p < 0.05). To obtain better results with ESWL in patients with gallbladder stone, the authors propose a more strict inclusion criteria, which is the patient with a single, radiolucent stone smaller than 2 cm

  8. A new approach to assess the chemical composition of powder deposits damaging the stone surfaces of historical monuments.

    Science.gov (United States)

    Fermo, Paola; Turrion, Raquel Gonzalez; Rosa, Mario; Omegna, Alessandra

    2015-04-01

    The issue of conservation of the monumental heritage worldwide is mainly related to atmospheric pollution that causes the degradation of stone surfaces. The powder deposits present on the stone monuments reflect the composition of the aerosol particulate matter (PM) to which the surfaces are exposed, so the chemical characterization of the outermost damaged layers is necessary in order to adopt mitigation measurements to reduce PM emissions. In the present paper, a new analytical approach is proposed to investigate the chemical composition of powder deposits present on Angera stone, a dolomitic rock used in the Richini courtyard, a masterpiece of Lombard Baroque and placed in Milan. Inorganic and organic components present in these deposits have been analyzed by IC (ion chromatography) and a new approach mainly bases on thermal analyses, respectively. Gypsum is the main inorganic constituent indicating a composition similar to that of black crusts, hard black patina covering the degraded building surfaces. Ammonium nitrate present in the powder is able to react with the stone substrate to form magnesium nitrate which can migrate into the porous stone. The carbonaceous fraction powder deposits (i.e. OC = Organic Carbon and EC = Elemental Carbon) have been quantified by a new simple thermal approach based on carbon hydrogen nitrogen (CHN) analysis. The presence of high concentration of EC confirms that the powder deposits are evolving to black crust. Low values of water-soluble organic carbon (WSOC, determined by total organic carbon-TOC), with respect to what is normally found in PM, may indicate a migration process of organic substances into the stone with a worsening of the conservation conditions. The presence of heavy metals of anthropogenic origin and acting as catalysts in the black crust formation process has been highlighted by SEM-EDS (electron microscopy coupled with an energy dispersive spectrometer) as well.

  9. Using a three-dimensional computer assisted stone volume estimates to evaluate extracorporeal shockwave lithotripsy treatment of kidney stones

    DEFF Research Database (Denmark)

    Bigum, Lene Hyldgaard; Ulriksen, Peter Sommer; Omar, Omar Salah

    2016-01-01

    Hospital between April 2013 and January 2014 and follow-up was possible in 77 (95 %) patients. NCCT was used before and after treatment. Treatment response was expressed as a reduction of the stone volume. Stone characteristics as the stone volumes, HU, SSD and localization were measured by radiologist...

  10. Steady as a rock: Biogeomorphic influence of nurse rocks and slope processes on kūpaoa (Dubautia menziesii) shrubs in Haleakalā Crater (Maui, Hawai'i)

    Science.gov (United States)

    Pérez, Francisco L.

    2017-10-01

    This study examines biogeomorphic interactions between nurse rocks, slope processes, and 300 kūpaoa (Dubautia menziesii) shrubs in Haleakalā Crater (Maui, Hawai'i). Research objectives were to: assess the association of kūpaoa with substrates upslope and downslope of plants, and proximity to the closest rock uphill; contrast shrub/substrate relationships with site frequency of sediment types; measure surface soil shear-strength and compressibility on 50 paired locations near boulders; and investigate the aggregation characteristics and spatial patterns of kūpaoa in relation to rock and substrate variation. Data analyzed came from three 100-plant surveys at 3 sites: a plant census at 2720-2975 m altitude, and wandering-quarter transects (WQTs) across two areas (2610-2710 m); ground sediment cover was estimated along four phototransects on these sites. Data for the three 100-plant surveys included substrate type-outcrops, blocks, cobbles, pebbles, exposed soil, organic litter-upslope from each plant, and distance to the largest rock upslope. The two surveys examined along WQTs included substrate type found downslope from kūpaoa, plant height, plant diameters across and along the slope, and distance between successively censused plants. Most plants grew downslope of nurse rocks; > 74% were adjacent to blocks or outcrops, and > 17% near cobbles. Plants showed avoidance for finer substrates; only 5.3% and 2.7% grew on/near bare soils and pebbles, respectively. About 92% of kūpaoa were ≤ 10 cm downslope of rocks; > 89% grew ≤ 2 cm away, and 83% in direct contact with a rock. Some seedlings also grew on pukiawe (Leptecophylla tameiameiae) nurse plants. Several stable rock microsites protected plants from disturbance by slope processes causing debris shift. Site sediments were significantly finer than substrates near plants; shrubs grew preferentially adjacent to boulders > 20 cm wide, which were more common near plants than across sites. Soils downslope of 50

  11. Stone anchors of India: Findings, classification and significance.

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.

    Various types of stone anchors have been observed during inshore and offshore explorations along the east and west coasts of India. The earliest stone anchors of India have been recorded from the Harappan sites (3rd millennium BC), but their shape...

  12. Shielding features of quarry stone

    International Nuclear Information System (INIS)

    Hernandez V, C.; Contreras S, H.; Hernandez A, L.; Baltazar R, A.; Escareno J, E.; Mares E, C. A.; Vega C, H. R.

    2010-10-01

    Quarry stone lineal attenuation coefficient for gamma-rays has been obtained. In Zacatecas, quarry stone is widely utilized as a decorative item in buildings, however its shielding features against gamma-rays unknown. The aim of this work is to determine the shielding properties of quarry stone against γ-rays using Monte Carlo calculations where a detailed model of a good geometry experimental setup was carried out. In the calculations 10 pieces 10 X 10 cm 2 of different thickness were utilized to evaluate the photons transmission as the quarry stone thickness is increased. It was noticed that transmitted photons decay away as the shield thickness is increased, these results were fitted to an exponential function were the linear attenuation coefficient was estimated. Also, using XCOM code the linear attenuation coefficient from several keV up to 100 MeV was estimated. From the comparison between Monte Carlo results and XCOM calculations a good agreement was found. For 0.662 MeV γ-rays the attenuation coefficient of quarry stone, whose density is 2.413 g-cm -3 , is 0.1798 cm -1 , this mean a X 1/2 = 3.9 cm, X 1/4 = 7.7 cm, X 1/10 = 12.8 cm, and X 1/100 = 25.6 cm. Having the information of quarry stone performance as shielding give the chance to use this material to shield X and γ-ray facilities. (Author)

  13. Gaussian multiscale aggregation applied to segmentation in hand biometrics.

    Science.gov (United States)

    de Santos Sierra, Alberto; Avila, Carmen Sánchez; Casanova, Javier Guerra; del Pozo, Gonzalo Bailador

    2011-01-01

    This paper presents an image segmentation algorithm based on Gaussian multiscale aggregation oriented to hand biometric applications. The method is able to isolate the hand from a wide variety of background textures such as carpets, fabric, glass, grass, soil or stones. The evaluation was carried out by using a publicly available synthetic database with 408,000 hand images in different backgrounds, comparing the performance in terms of accuracy and computational cost to two competitive segmentation methods existing in literature, namely Lossy Data Compression (LDC) and Normalized Cuts (NCuts). The results highlight that the proposed method outperforms current competitive segmentation methods with regard to computational cost, time performance, accuracy and memory usage.

  14. Optimal policies for aggregate recycling from decommissioned forest roads.

    Science.gov (United States)

    Thompson, Matthew; Sessions, John

    2008-08-01

    To mitigate the adverse environmental impact of forest roads, especially degradation of endangered salmonid habitat, many public and private land managers in the western United States are actively decommissioning roads where practical and affordable. Road decommissioning is associated with reduced long-term environmental impact. When decommissioning a road, it may be possible to recover some aggregate (crushed rock) from the road surface. Aggregate is used on many low volume forest roads to reduce wheel stresses transferred to the subgrade, reduce erosion, reduce maintenance costs, and improve driver comfort. Previous studies have demonstrated the potential for aggregate to be recovered and used elsewhere on the road network, at a reduced cost compared to purchasing aggregate from a quarry. This article investigates the potential for aggregate recycling to provide an economic incentive to decommission additional roads by reducing transport distance and aggregate procurement costs for other actively used roads. Decommissioning additional roads may, in turn, result in improved aquatic habitat. We present real-world examples of aggregate recycling and discuss the advantages of doing so. Further, we present mixed integer formulations to determine optimal levels of aggregate recycling under economic and environmental objectives. Tested on an example road network, incorporation of aggregate recycling demonstrates substantial cost-savings relative to a baseline scenario without recycling, increasing the likelihood of road decommissioning and reduced habitat degradation. We find that aggregate recycling can result in up to 24% in cost savings (economic objective) and up to 890% in additional length of roads decommissioned (environmental objective).

  15. Extracorporeal shock wave lithotripsy for urinary stones

    International Nuclear Information System (INIS)

    Shinn, Kyung Sub; Kim, Hyun; Byun, Jae Young; Lee, Myung Hee; Bahk, Yong Whee; Park, Yong Hyun

    1988-01-01

    Extracorporeal shock wave lithotripsy (ESWL) is a new noninvasive treatment modality for urinary stones, and it sometimes is to necessitate endourologic techniques. ESWL with an Edap lithotripter which uses piezo-electric elements, was performed in 142 cases (130 patients) with urinary stones including 68 in calices, 30 in pelves, and 44 in ureters. Technical factors were 100 storages at 5 to 10 pulse rates/sec and 70-100% adjustable power for about 60 minutes (15-90) for renal stones, and 200 storages at 20 pulse rates/sec and 100% adjustable power for about 60 minutes for ureteral stones in a single treatment under stone localization by 5 MHz ultrasonic sector scanner. All patients were treated at Kangnam St.Mary's Hospital of Catholic University Medical College during the 5 months period from May 1, 1987. Every patient had pre-treatment chest, plain abdomen, intravenous urogram and ultrasonogram studies and post-treatment follow-up abdominal radiograms in 1 to 3 months after ESWL.The overall success rate of ESWL in 142 cases was 94.4%. Eight out of 142 cases were successful. Thus, 134 cases were analysed. Of these, 58 cases (43.3%) received one treatment, 33 cases (24.6%) two treatments, 16 cases (11.9%) three treatments and 27 cases (20.2%) more than four treatments. Renal stones were more successfully treated (98.0%) than ureteral stones (88.1%), and calyceal stones presented the highest success rate (98.5%). The stones as small as 5 to 10 mm in size were easily fragmented and the stones of round of oval shape were more easily pulverized than those of staghorn or amorphous shape. The adjunctive endourlogic techniques such as percutaneous nephrostomy, ureteral catheterization or internal ureteral stenting with a double pigtail catheter were required in 17 cases (11.9%). Complications of ESWL for urolithiasis included hematuria (84.5%), flank pain (8.5%) and fever (5.6%), which were controlled without specific treatment. ESWL using ultrasonic localization was

  16. Extracorporeal shock wave lithotripsy for urinary stones

    Energy Technology Data Exchange (ETDEWEB)

    Shinn, Kyung Sub; Kim, Hyun; Byun, Jae Young; Lee, Myung Hee; Bahk, Yong Whee; Park, Yong Hyun [Kangnam St. Mary' s Hospital, Catholic University Medical College, Seoul (Korea, Republic of)

    1988-06-15

    Extracorporeal shock wave lithotripsy (ESWL) is a new noninvasive treatment modality for urinary stones, and it sometimes is to necessitate endourologic techniques. ESWL with an Edap lithotripter which uses piezo-electric elements, was performed in 142 cases (130 patients) with urinary stones including 68 in calices, 30 in pelves, and 44 in ureters. Technical factors were 100 storages at 5 to 10 pulse rates/sec and 70-100% adjustable power for about 60 minutes (15-90) for renal stones, and 200 storages at 20 pulse rates/sec and 100% adjustable power for about 60 minutes for ureteral stones in a single treatment under stone localization by 5 MHz ultrasonic sector scanner. All patients were treated at Kangnam St.Mary's Hospital of Catholic University Medical College during the 5 months period from May 1, 1987. Every patient had pre-treatment chest, plain abdomen, intravenous urogram and ultrasonogram studies and post-treatment follow-up abdominal radiograms in 1 to 3 months after ESWL.The overall success rate of ESWL in 142 cases was 94.4%. Eight out of 142 cases were successful. Thus, 134 cases were analysed. Of these, 58 cases (43.3%) received one treatment, 33 cases (24.6%) two treatments, 16 cases (11.9%) three treatments and 27 cases (20.2%) more than four treatments. Renal stones were more successfully treated (98.0%) than ureteral stones (88.1%), and calyceal stones presented the highest success rate (98.5%). The stones as small as 5 to 10 mm in size were easily fragmented and the stones of round of oval shape were more easily pulverized than those of staghorn or amorphous shape. The adjunctive endourlogic techniques such as percutaneous nephrostomy, ureteral catheterization or internal ureteral stenting with a double pigtail catheter were required in 17 cases (11.9%). Complications of ESWL for urolithiasis included hematuria (84.5%), flank pain (8.5%) and fever (5.6%), which were controlled without specific treatment. ESWL using ultrasonic localization

  17. Predictions of outcomes of renal stones after extracorporeal shock wave lithotripsy from stone characteristics determined by unenhanced helical computed tomography: a multivariate analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Li-Jen; Wong, Yon-Cheong [Chang Gung University, Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Taipei (Taiwan); Chuang, Cheng-Keng; Chu, Sheng-Hsien; Chen, Chih-Shou; Chiang, Yang-Jen [Chang Gung University, Department of Urology, Chang Gung Memorial Hospital, Taipei (Taiwan); See, Lai-Chu [Chang Gung University, Department of Biostatistics Center, Chang Gung Memorial Hospital, Taipei (Taiwan)

    2005-11-01

    The aim of our study is to analyze the relationships between the characteristics of renal stones determined by unenhanced helical computed tomography (UHCT) and their outcomes after extracorporeal shock wave lithotripsy (ESWL) as well as to predict ESWL outcomes of renal stones by their UHCT characteristics with the use of multivariate analysis. During a 7-month period, 80 adult patients with renal stones underwent ESWL as well as UHCT both before and 3 months after ESWL. Of the 80 patients, 42 patients were classified as ESWL successes and 38 as ESWL failures based on their post-ESWL UHCT findings. For pre-ESWL UHCT, a stone number of more than 2 (P=0.0236), a maximal stone size of greater than 12 mm (P<0.0001), a stone burden of more than 700 mm{sup 3} (P<0.0001), a maximal stone density of more than 900 HU (P=0.0008) and nonround/oval stones (P=0.0007) were associated with ESWL failure outcomes. Multivariate analysis demonstrated that a stone burden of more than 700 mm{sup 3} (P=0.0003), the presence of nonround/oval stones (P=0.0072) and a maximal stone density of more than 900 HU (P=0.0430) were statistically significant predictors of a failure outcome for ESWL. Thus, the analysis of stone characteristics of renal stones by UHCT is helpful in selecting appropriate patients undergoing ESWL for favorable outcomes and reduces the overall costs of the treatment of renal stones. (orig.)

  18. Analysis of kidney stones by PIXE and RBS techniques

    Energy Technology Data Exchange (ETDEWEB)

    Alkofai, M M [Physics Dept., Yarmouk University, Irbid, (Jordan); Hallak, A B [Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261, (Saudi Arabia)

    1995-10-01

    Human kidney stones were analyzed by PIXE and RBS techniques using 2 MeV He{sup ++} beam. The stones were found to contain the elements: C, N, O, F, Na, Mg, Si, P, S, Cl, K, Ca, Fe and Br. Results obtained by PIXE agree with the results obtained by RBS within experimental errors. A Mechanism for the formation of the kidney stones is suggested. 3 figs., 1 tab.

  19. Analysis of kidney stones by PIXE and RBS techniques

    International Nuclear Information System (INIS)

    Alkofai, M.M.; Hallak, A.B.

    1995-01-01

    Human kidney stones were analyzed by PIXE and RBS techniques using 2 MeV He ++ beam. The stones were found to contain the elements: C, N, O, F, Na, Mg, Si, P, S, Cl, K, Ca, Fe and Br. Results obtained by PIXE agree with the results obtained by RBS within experimental errors. A Mechanism for the formation of the kidney stones is suggested. 3 figs., 1 tab

  20. Factors affecting lower calyceal stone clearance after Extracorporeal ...

    African Journals Online (AJOL)

    shanker

    have been identified [1,3]. These include stone characteristics, the type of lithotripter used, LPC anatomy and body habitus. For iso- lated LPC stones, the pelvicalyceal angle, infundibulum length and width are considered important determinants for stone clearance. The impact of body habitus on stone clearance has so far ...

  1. Emergency management of ureteral stones: Recent advances

    Directory of Open Access Journals (Sweden)

    Luis Osorio

    2008-01-01

    Full Text Available Most ureteral stones can be observed with reasonable expectation of uneventful stone passage. When an active ureteral stone treatment is warranted, the best procedure to choose is dependent on several factors, besides stone size and location, including operators′ experience, patients′ preference, available equipment and related costs. Placement of double-J stent or nephrostomy tube represents the classical procedures performed in a renal colic due to acute ureteral obstruction when the conservative drug therapy does not resolve the symptoms. These maneuvers are usually followed by ureteroscopy or extracorporeal shockwave lithotripsy, which currently represent the mainstay of treatment for ureteral stones. In this review paper a literature search was performed to identify reports dealing with emergency management of renal colic due to ureteral stones. The main aspects related to this debated issue are analyzed and the advantages and disadvantages of each treatment option are carefully discussed.

  2. Emergency management of ureteral stones: Recent advances.

    Science.gov (United States)

    Osorio, Luis; Lima, Estêvão; Autorino, Riccardo; Marcelo, Filinto

    2008-10-01

    Most ureteral stones can be observed with reasonable expectation of uneventful stone passage. When an active ureteral stone treatment is warranted, the best procedure to choose is dependent on several factors, besides stone size and location, including operators' experience, patients' preference, available equipment and related costs. Placement of double-J stent or nephrostomy tube represents the classical procedures performed in a renal colic due to acute ureteral obstruction when the conservative drug therapy does not resolve the symptoms. These maneuvers are usually followed by ureteroscopy or extracorporeal shockwave lithotripsy, which currently represent the mainstay of treatment for ureteral stones. In this review paper a literature search was performed to identify reports dealing with emergency management of renal colic due to ureteral stones. The main aspects related to this debated issue are analyzed and the advantages and disadvantages of each treatment option are carefully discussed.

  3. Bladder stones after bladder augmentation are not what they seem.

    Science.gov (United States)

    Szymanski, Konrad M; Misseri, Rosalia; Whittam, Benjamin; Lingeman, James E; Amstutz, Sable; Ring, Joshua D; Kaefer, Martin; Rink, Richard C; Cain, Mark P

    2016-04-01

    Bladder and renal calculi after bladder augmentation are thought to be primarily infectious, yet few studies have reported stone composition. The primary aim was to assess bladder stone composition after augmentation, and renal stone composition in those with subsequent nephrolithiasis. The exploratory secondary aim was to screen for possible risk factors for developing infectious stones. Patients treated for bladder stones after bladder augmentation at the present institution between 1981 and 2012 were retrospectively reviewed. Data were collected on demographics, surgeries and stone composition. Patients without stone analysis were excluded. Stones containing struvite, carbonate apatite or ammonium acid ureate were classified as infectious. The following variables were analyzed for a possible association with infectious bladder stone composition: gender, history of cloacal exstrophy, ambulatory status, nephrolithiasis, recurrent urea-splitting urinary tract infections, first vs recurrent stones, timing of presentation with a calculus, history of bladder neck procedures, catheterizable channel and vesicoureteral reflux. Fisher's exact test was used for analysis. Of the 107 patients with bladder stones after bladder augmentation, 85 met inclusion criteria. Median age at augmentation was 8.0 years (follow-up 10.8 years). Forty-four patients (51.8%) recurred (14 multiple recurrences, 143 bladder stones). Renal calculi developed in 19 (22.4%) patients with a bladder stone, and 10 (52.6%) recurred (30 renal stones). Overall, 30.8% of bladder stones were non-infectious (Table). Among patients recurring after an infectious bladder stone, 30.4% recurred with a non-infectious one. Among patients recurring after a non-infectious stone, 84.6% recurred with a non-infectious one (P = 0.005). Compared with bladder stones, renal stones were more likely to be non-infectious (60.0%, P = 0.003). Of patients with recurrent renal calculi after an infectious stone, 40.0% recurred with

  4. Cover stones on liquefiable soil bed under waves

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Hatipoglu, Figen; Fredsøe, Jørgen

    2010-01-01

    The paper describes the results of an experimental study on the behavior of cover stones on a liquefiable soil bed exposed to a progressive wave. The soil was silt with d50=0.098mm. Stones, the size of 4cm, were used as cover material. The effect of packing density of stones, and that of number...... of stone layers (including the effect of an intermediate filter layer) were investigated. Pore pressure was measured across the soil depth. The experiments show that the soil liquefaction depended mainly on two parameters: the packing density of stones, and the number of stone layers. When the liquefaction...

  5. CONGLOMERATE ROCKS "BRECCIA VERDE ANTICA" ARCHAEOLOGY, PETROLOGY, DETERIORATION AND TECHNOLOGY OF QUARRYING AT HAMMAMAT QUARRIES IN THE EASTEREN DESERT.

    Directory of Open Access Journals (Sweden)

    dr.HESHAM ABBAS KMALLY

    2010-01-01

    Full Text Available One of the most interesting of the monumental rocks of Egypt is the green conglomerates of the Hammamat valley which was used for bowls, vessels, sarcophagus and other objects, from a very early period. The quarries of wadi Hammamat produced the green ornamental stone known in Roman period as "Breccia verde antica". Generally the ancient conglomerate was used occasionally in Egypt at pharaonic time and late period, but it was quarried chiefly by the Roman for export to Italy. The conglomerate rocks range from coarse to fine conglomerates. They are composed of great assortment of rock fragments such as meta-sediments, meta-volcanic and granites. Some pebbles of the coarse conglomerates are previously deposited conglomerates. Pollution, humidity or moisture, solar radiation, rainfall and groundwater represent important factors for disintegration of green conglomerate rocks. Many types of destruction have been noted such as micro-cracks, fractures, joints, exfoliation, crumbling, discoloration, leaching and staining with iron oxides. The conglomerate rock sometimes changes into fragmented, soft residual and parent matter of the soil. Moreover, individual grains of feldspar and quartz begin to become loosened and the rock shows superficial granular disintegration due to, growth of salts and physiochemical weathering

  6. Bariatric Surgery and Urinary Stone Disease

    Directory of Open Access Journals (Sweden)

    Cevahir Ozer

    2016-07-01

    Full Text Available Obesity is a major public health problem and has been suggested to play a role in the etiology of urinary tract stone disease. Furthermore, the increasingly widespread use of surgery in the treatment of obesity also is related with urinary stone disease. In daily practice, patients to whom obesity surgery has been planned or who have undergone obesity surgery are seen more frequently. This review aims to highlight the urological evaluation and management of this patient group.

  7. Integrating GIS-based geologic mapping, LiDAR-based lineament analysis and site specific rock slope data to delineate a zone of existing and potential rock slope instability located along the grandfather mountain window-Linville Falls shear zone contact, Southern Appalachian Mountains, Watauga County, North Carolina

    Science.gov (United States)

    Gillon, K.A.; Wooten, R.M.; Latham, R.L.; Witt, A.W.; Douglas, T.J.; Bauer, J.B.; Fuemmeler, S.J.

    2009-01-01

    Landslide hazard maps of Watauga County identify >2200 landslides, model debris flow susceptibility, and evaluate a 14km x 0.5km zone of existing and potential rock slope instability (ZEPRSI) near the Town of Boone. The ZEPRSI encompasses west-northwest trending (WNWT) topographic ridges where 14 active/past-active rock/weathered rock slides occur mainly in rocks of the Grandfather Mountain Window (GMW). The north side of this ridgeline is the GMW / Linville Falls Fault (LFF) contact. Sheared rocks of the Linville Falls Shear Zone (LFSZ) occur along the ridge and locally in the valley north of the contact. The valley is underlain principally by layered granitic gneiss comprising the Linville Falls/Beech Mountain/Stone Mountain Thrust Sheet. The integration of ArcGIS??? - format digital geologic and lineament mapping on a 6m LiDAR (Light Detecting and Ranging) digital elevation model (DEM) base, and kinematic analyses of site specific rock slope data (e.g., presence and degree of ductile and brittle deformation fabrics, rock type, rock weathering state) indicate: WNWT lineaments are expressions of a regionally extensive zone of fractures and faults; and ZEPRSI rock slope failures concentrate along excavated, north-facing LFF/LFSZ slopes where brittle fabrics overprint older metamorphic foliations, and other fractures create side and back release surfaces. Copyright 2009 ARMA, American Rock Mechanics Association.

  8. Calcium Stone Growth in Urine from Cystic Fibrosis Patients and Healthy Controls

    Science.gov (United States)

    McSorley, Anita; Jones, Andrew M.; Webb, A. Kevin; Rao, P. Nagaraj; Kavanagh, John P.

    2007-04-01

    Cystic fibrosis patients have an increased risk of renal stone disease. There is some evidence that this may be related to a different excretory pattern of stone risk factors, but an alternative hypothesis, that the urine of cystic fibrosis patients is deficient in urinary inhibitors of crystallization and stone formation has not been tested. Here we have grown calcium stones, in vitro, in the presence of urine from healthy controls and compared this with growth in the presence of urine from cystic fibrosis patients. A stone farm was used to grow twelve calcium stones simultaneously, firstly in artificial urine for about 200 hours and then in 90% whole human urine for another 500 hours. Six of the stones received urine from healthy controls and six received urine from adult cystic fibrosis patients. There were no significant differences in stone mass at any of the key time points or in the overall growth pattern (p>0.05) between stones destined for, or treated with, urine from CF patients and the controls. Human urine greatly inhibited stone growth in vitro but there was no difference in the growth rate in urine from healthy controls and CF patients. This refutes the hypothesis that a tendency for a higher prevalence of urinary stones in CF patients is related to a deficiency in inhibitory activity.

  9. Can ureteral stones cause pain without causing hydronephrosis?

    Science.gov (United States)

    Song, Yan; Hernandez, Natalia; Gee, Michael S; Noble, Vicki E; Eisner, Brian H

    2016-09-01

    While computerized tomography (CT) is the gold standard for diagnosis of ureterolithiasis, ultrasound is a less costly and radiation-free alternative which is commonly used to evaluate patients with ureteral colic. The purpose of this study was to evaluate the frequency with which patients with ureteral stones and renal colic demonstrate hydronephrosis in order to better understand the evaluation of these patients. Two hundred and forty-eight consecutive patients presenting with ureteral colic and diagnosed with a single unilateral ureteral stone on CT scan in an urban tertiary care emergency department were retrospectively reviewed. Radiology reports were reviewed for stone size, diagnosis, and degree of hydronephrosis. Of the 248 patients evaluated for suspected ureteral stone, 221 (89.1 %) demonstrated any hydronephrosis, while 27 (10.9 %) did not. Hydronephrosis grade, available in 194 patients, was as follows: mild-70.6 %, moderate-27.8 %, and severe-1.5 %. Mean patient age was 47.0 years (SD 15.5), gender distribution was 35.9 % female and 64.1 % male, and mean stone axial diameter was 4.1 mm (SD 2.4). Stone location was as follows: ureteropelvic junction-4.1 %, proximal ureter-21 %, distal ureter-24.9 %, and ureterovesical junction-47.1 %. Axial stone diameter and coronal length (craniocaudal) were both significant predictors of degree of hydronephrosis (ANOVA, p hydronephrosis. In patients with ureteral stones and colic, nearly 11 % do not demonstrate any hydronephrosis and a majority (nearly 71 %) will demonstrate only mild hydronephrosis. Stone diameter appears to be related to degree of hydronephrosis, whereas age, gender, and stone location are not. The lower incidence of hydronephrosis for small stones causing renal colic may explain the lower diagnostic accuracy of ultrasound when compared to CT for detecting ureteral stones.

  10. Preliminary Study on Controlling Black Fungi Dwelling on Stone Monuments by Using a Microwave Heating System

    Directory of Open Access Journals (Sweden)

    Oana-Adriana CUZMAN

    2013-06-01

    Full Text Available Microcolonial black fungi have their natural ecological niche on rocks and walls of hypogean environments, playing an important role in the deterioration of materials and aesthetical alteration of monumental stones and mortars. Three black fungi (Sarcinomyces sp., Pithomyces sp. and Scolecobasidium sp. have been isolated from cultural assets of historical interest. These fungal strains have been used to test the microwave heating method as a new control methodology for eradicating the fungal biological growth on cultural stone artifacts. This methodology is based on a 2.45 GHz microwave electromagnetic radiation, generated by a new apparatus with an appropriate applicator. The first results showed the best dose of 65°C for three minutes, for all the investigated fungal strains. This methodology is very promising because is safety for the operator and the environment, and can be easily applied on site. The use of this method to kill biodeteriogens can avoid the application of chemicals formulates potentially dangerous for substrates and environment.

  11. Regional and detailed research studies for stone resources in Korea

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    This report consists of 6 subjects. 1) A study on the potentiality of building stone development from granite mass within Pocheon area, Kyeonggi Province. 2) The research on the variance of color and glossiness by means of Weather-Ometer. 3) Regional research studies on granites in Gimje-Yeonggwang area. 4) A study on the industrialization of building stones and industrial stone crafts - Study on the causes of stone weathering. 5) Borehole radar survey at the granite quarry mine, Pocheon, Kyounggi province. 6) Borehole radar diffraction tomography. (author). refs., tabs., figs.

  12. Anholt Rosetta Stones

    DEFF Research Database (Denmark)

    Trempe Jr., Robert B.; Buthke, Jan

    2017-01-01

    This book records and celebrates the research finding of Anholt Island by students from Studio 2B, Arkitektskolen Aarhus, These mahogany constructions are our architectural versions of a Rosetta Stone. These are constructs that record layers of information about Anholt island through virtual...... and physical techniques, where each step and mechanic imparts and inscribes knowledge beyond the 1:1. These constructs are visual keys, used to inspire and influence all decision-making processes in a design project. These architectural Rosetta Stones document and amplify quantitative information about a site...

  13. Conservation and restoration of natural building stones monitored through non-destructive X-ray computed tomography

    Science.gov (United States)

    Jacobs, P. Js; Cnudde, V.

    2003-04-01

    X-ray computed micro-tomography (μCT) is a promising non-destructive imaging technique to study building materials. μCT analysis provides information on the internal structure and petrophysical properties of small samples (size up to 2 cm diameter and 6 cm height), with to date a maximum resolution of 10 μm for commercial systems (Skyscan 1072). μCT allows visualising and measuring complete three-dimensional object structures without sample preparation. Possible applications of the μCT-technique for the monitoring of natural building stones are multiple: (i) to determine non-destructively porosity based on 3D images, (ii) to visualise weathering phenomena at the μ-scale, (iii) to understand the rationale of weathering processes, (iv) to visualise the presence of waterrepellents and consolidation products, (v) to monitor the protective effects of these products during weathering in order to understand the underlying weathering mechanisms and (vi) to provide advise on the suitability of products for the treatment of a particular rock-type. μCT-technique in combination with micro-Raman spectroscopy could prove to be a powerful tool for the future, as the combination of 3D visualisation and 2D chemical determination of inorganic as well as organic components could provide new insights to optimise conservation and restoration techniques of building materials. Determining the penetration depth of restoration products, used to consolidate or to protect natural building stones from weathering, is crucial if the application of conservation products is planned. Every type of natural building stone has its own petrophysical characteristics and each rock type reacts differently on the various restoration products available on the market. To assess the penetration depth and the effectiveness of a certain restoration product, μCT technology in combination with micro-Raman spectroscopy could be applied. Due to its non-destructive character and its resolution down to

  14. A pilot study of the effect of sodium thiosulfate on urinary lithogenicity and associated metabolic acid load in non-stone formers and stone formers with hypercalciuria.

    Directory of Open Access Journals (Sweden)

    Onyeka W Okonkwo

    Full Text Available BACKGROUND AND OBJECTIVES: Sodium thiosulfate (STS reduced calcium stone formation in both humans and genetic hypercalciuric stone forming (GHS rats. We sought to measure urine chemistry changes resulting from STS administration in people. DESIGN SETTING PARTICIPANTS MEASUREMENTS: STS was given to healthy and hypercalciuric stone forming adults. Five normal non-stone forming adults (mean age 33 years, and 5 people with idiopathic hypercalciuria and calcium kidney stones (mean age 66 years participated. Two baseline 24-hour urine collections were performed on days 2 and 3 of 3 days of self-selected diets. Subjects then drank STS 10 mmol twice a day for 7 days and did urine collections while repeating the self-selected diet. Results were compared by non-parametric Wilcoxon signed rank test. The primary outcome was the resulting change in urine chemistry. RESULTS: STS administration did not cause a significant change in urinary calcium excretion in either group. In both groups, 24 hour urinary ammonium (P = 0.005 and sulfate excretion (P = 0.007 increased, and urinary pH fell (P = 0.005; citrate excretion fell (P<0.05 in hypercalciuric participants but not in non-stone formers. Among stone formers with hypercalciuria, 3 of 5 patients had measurement of serum HCO3 concentration after the STS period: it did not change. The net effect was an increase in supersaturation of uric acid, and no change in supersaturation of calcium oxalate or calcium phosphate. CONCLUSIONS: The basis for studies demonstrating that STS prevented stones in rats and people was not reflected by the changes in urine chemistry reported here. Although serum HCO3 did not change, urine tests suggested an acid load in both non-stone forming and hypercalciuric stone-forming participants. The long term safety of STS needs to be determined before the drug can be tested in humans for long-term prevention of stone recurrence.

  15. Wait-and-see policy versus cholecystectomy after endoscopic sphincterotomy for bile-duct stones in high-risk patients with co-existing gallbladder stones: a prospective randomised trial.

    Science.gov (United States)

    Zargar, Showkat A; Mushtaq, Mosin; Beg, Mashkoor A; Javaid, Gul; Khan, Bashir A; Hassan, Rayhana; Kasana, Reyaz A; Tabassum, Sameena

    2014-03-01

    Endoscopic sphincterotomy (ES) is one of the most important advances in the treatment of common bile duct (CBD) stones. However, the use of ES to remove CBD stones in high-risk patients without cholecystectomy is still debatable. The aim of this study was to compare the efficacy of a wait-and-see policy versus cholecystectomy after ES for CBD stones in high-risk patients with co-existing cholelithiasis. A total of 162 patients after undergoing ES with the clearance of CBD stones were randomised after informed consent to cholecystectomy or conservative management of their gallbladder stones. The results indicated that cholecystectomy after ES for CBD stones significantly reduced the biliary complications in high-risk patients. Every patient who has both CBD stones and gallstones with significant co-morbid illnesses, after clearance of CBD stones by ES, should undergo early cholecystectomy. Copyright © 2014 Arab Journal of Gastroenterology. Published by Elsevier Ltd. All rights reserved.

  16. Evaluation of possible host rocks for China's high level radioactive waste repository and the progress in site characterization at the Beishan potential site in NW China's Gansu province

    International Nuclear Information System (INIS)

    Wang Ju; Jin Yuanxin; Chen Zhangru; Chen Weiming; Wang Wenguang

    2000-01-01

    Evaluation of possible host rocks for China's high level radioactive waste repository is summarized in this paper. The distribution and characteristics of granite, tuff, clay stone, salt and loess in China are described, while maps showing the distribution of host rocks are presented. Because of the wide distribution, large scale, good heat conductivity and suitable mechanical properties, granite is considered as the most potential host rock. Some granite bodies distributed in NW China, SW China, South China and Inner Mongolia have been selected as potential areas. Detailed site characterization at Beishan area, Gansu Province NW China is in progress

  17. The Civil Palaces in Gravina street, Alicante: building stones and salt weathering

    OpenAIRE

    Louis, M.; García del Cura, M. A.; Spairani, Y.; de Blas, D.

    2001-01-01

    This paper presents a study into the architecture and construction of the 18th Century Civil Palaces located in Gravina street (Provincial Museum of Fine Arts of Alicante), the building stones used and the mineral related decay processes that these materials have suffered. The original building stones and other stones used in subsequent restorations in these Civil Palaces are bioclastic limestones and/or calcarenites (San Julian Stone and Bateig Stone). Campello st...

  18. The potential for ore, industrial minerals and commercial stones in the Simpevarp area

    International Nuclear Information System (INIS)

    Lindroos, Hardy

    2004-10-01

    On behalf of SKB (the Swedish Nuclear Fuel and Waste Management Company), a survey has been made of existing information concerning the potential for ore, industrial minerals and commercial stones in and around the two candidate areas for a deep repository in Oskarshamn. A deep repository for spent nuclear fuel should not be located in a rock type or in an area where mineral extraction might be considered in the future, since this would make it difficult or impossible to exploit this natural resource. Avoiding such areas reduces the risk that people in the future will come into contact with the deep repository through mineral prospecting or mining activities.The survey has made use of the geoscientific information compiled in the more regional investigations in Oskarshamn Municipality in 1998-99. The new information after the municipal study includes extensive geophysical measurements from both the air and the ground. The results of the recently completed geophysical helicopter survey of the Simpevarp area are presented in a special chapter. The judgement of an area's ore potential is in part based on the evaluation of these geophysical measurements. In order to be better able to judge the ore potential, a geochemical investigation of soil samples, including reanalysing of older samples collected by the Geological Survey of Sweden (SGU), has been carried out. The report also discusses prospecting efforts in the area as well as relevant Swedish mining legislation. In cooperation with SGU a mineral resource map of the Simpevarp area has been prepared. The map shows two areas with a potential for commercial stones, namely the granites at Goetemar and Uthammar, situated in the northernmost respectively the southernmost part of the study area. Furthermore, the Goetemar granite has probably a small potential for ores containing tin (Sn) and/or wolfram (W). Although no mineralizations of this type have so far been found, the Goetemar granite area may be unsuitable or for

  19. The potential for ore, industrial minerals and commercial stones in the Simpevarp area

    Energy Technology Data Exchange (ETDEWEB)

    Lindroos, Hardy [MIRAB Mineral Resurser AB, Uppsla (Sweden)

    2004-10-01

    On behalf of SKB (the Swedish Nuclear Fuel and Waste Management Company), a survey has been made of existing information concerning the potential for ore, industrial minerals and commercial stones in and around the two candidate areas for a deep repository in Oskarshamn. A deep repository for spent nuclear fuel should not be located in a rock type or in an area where mineral extraction might be considered in the future, since this would make it difficult or impossible to exploit this natural resource. Avoiding such areas reduces the risk that people in the future will come into contact with the deep repository through mineral prospecting or mining activities.The survey has made use of the geoscientific information compiled in the more regional investigations in Oskarshamn Municipality in 1998-99. The new information after the municipal study includes extensive geophysical measurements from both the air and the ground. The results of the recently completed geophysical helicopter survey of the Simpevarp area are presented in a special chapter. The judgement of an area's ore potential is in part based on the evaluation of these geophysical measurements. In order to be better able to judge the ore potential, a geochemical investigation of soil samples, including reanalysing of older samples collected by the Geological Survey of Sweden (SGU), has been carried out. The report also discusses prospecting efforts in the area as well as relevant Swedish mining legislation. In cooperation with SGU a mineral resource map of the Simpevarp area has been prepared. The map shows two areas with a potential for commercial stones, namely the granites at Goetemar and Uthammar, situated in the northernmost respectively the southernmost part of the study area. Furthermore, the Goetemar granite has probably a small potential for ores containing tin (Sn) and/or wolfram (W). Although no mineralizations of this type have so far been found, the Goetemar granite area may be unsuitable or

  20. Instrumental neutron activation analysis of kidney stones

    International Nuclear Information System (INIS)

    Sarmani, S.; Kuan, L.L.; Bakar, M.A.A.

    1990-01-01

    Kidney stone samples of the types calcium oxalate, uric acid, and xanthine were analyzed for their elemental contents by neutron activation analysis to study both the elemental correlation and influence of element on stone precipitation processes. Elements, such as Al, Au, Br, Ca, Cl, Co, Cr, Fe,H, I, K, Mg, Na, Sb, Se, Sr, and Zn, were determined quantitatively. Calcium oxalate stones contained higher concentration of all the elements analyzed compared to uric acid or xanthine stones. The concentrations of Cl, Fe, K, Na, Sr, and Zn were relatively higher than Au, Co, Cr, and Sb. A positive correlation exists between Ca and Zn, whereas a negative correlation exists between Sr and Ca. Zinc may play an important role in the formation of calcium oxalate stone

  1. Temporally variable macroinvertebrate-stone relationships in streams

    DEFF Research Database (Denmark)

    Jacobsen, D.

    2005-01-01

    of fauna parameter and stone variable from different sampling dates (n=9-11) were rarely correlated to any of the measures of stream stability, this study has demonstrated high temporal variability in fauna-stone relationships (CV's of regression slopes). Consequently, temporally un-replicated studies......Stones were used to sample macroinvertebrates and characterise microhabitats at monthly or bimonthly intervals in six Ecuadorian streams covering a gradient in four different stability measures and other stream characteristics. The physical variables current velocity, water depth, horizontal...... of families vs. individuals) were related to the physical characteristics of individual stone habitats. My second objective was to quantify temporal variability in fauna-stone relationships and to analyse if such variability was related to overall stability of stream reaches. Partial Least Squares (PLS...

  2. Extracorporeal shock wave lithotripsy for gallbladder stones - an experimental and clinical study -

    International Nuclear Information System (INIS)

    Kim, Kun Sang; Park, Sil Moo; Lee, Jung Hyo; Kim, Young Goo; Song, Kounn Sik; Lee, Kwan Seh; Lee, Jong Beum; Kim, Sang Joon; Chang, Sun Taik

    1988-01-01

    Although many alternative treatment technics have been proposed recently for gallstone to substitute cholecystectomy, the extracorporeal shock wave lithotripsy (ESWL) for gallbladder stones has rarely been tried. We have carried out a series of experiments to evaluate how effective the ESWL for gallbladder stones in and how safe this procedure is. At first, in vitro shock were application was carried out to 10 gallbladder stones which were obtained from human gallbladder. Secondly, gallbladder stones were implanted to canine gallbladder and treated with shock wave. Lastly, a total of 41 volunteers with confirmed gallbladder stones were treated with shock wave and combined oral administration of ursodeoxycholic acid. In the in vitro experiment, all of the 10 gallstones were fragmented with variable firing rates and duration. In animal experiment, the implanted stones were successfully fragmented and the organs included in the pathway of shock wave were proved to be intact histologically. In human study, complete disappearance of gallstones was noted in 78.6% of patients with single radiolucent gallbladder stones, smaller than 2.5cm in the longest diameter. Two patients underwent cholecystectomy after ESWL due to sudden colic attack. One patient had experienced an episode of mild transient obstructive jaundice. It may be concluded that the ESWL for gallbladder stones is an effective and safe method of treatment of gallbladder stones in the selected cases, for example, small radiolucent stones, and the further study is needed to establish improved technology of the ESWL for gallbladder stones.

  3. Extracorporeal shock wave lithotripsy for gallbladder stones - an experimental and clinical study -

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kun Sang; Park, Sil Moo; Lee, Jung Hyo; Kim, Young Goo; Song, Kounn Sik; Lee, Kwan Seh; Lee, Jong Beum; Kim, Sang Joon; Chang, Sun Taik [Chung-Ang University College of Medicine, Seoul (Korea, Republic of)

    1988-08-15

    Although many alternative treatment technics have been proposed recently for gallstone to substitute cholecystectomy, the extracorporeal shock wave lithotripsy (ESWL) for gallbladder stones has rarely been tried. We have carried out a series of experiments to evaluate how effective the ESWL for gallbladder stones in and how safe this procedure is. At first, in vitro shock were application was carried out to 10 gallbladder stones which were obtained from human gallbladder. Secondly, gallbladder stones were implanted to canine gallbladder and treated with shock wave. Lastly, a total of 41 volunteers with confirmed gallbladder stones were treated with shock wave and combined oral administration of ursodeoxycholic acid. In the in vitro experiment, all of the 10 gallstones were fragmented with variable firing rates and duration. In animal experiment, the implanted stones were successfully fragmented and the organs included in the pathway of shock wave were proved to be intact histologically. In human study, complete disappearance of gallstones was noted in 78.6% of patients with single radiolucent gallbladder stones, smaller than 2.5cm in the longest diameter. Two patients underwent cholecystectomy after ESWL due to sudden colic attack. One patient had experienced an episode of mild transient obstructive jaundice. It may be concluded that the ESWL for gallbladder stones is an effective and safe method of treatment of gallbladder stones in the selected cases, for example, small radiolucent stones, and the further study is needed to establish improved technology of the ESWL for gallbladder stones.

  4. Development of a laboratory model of a phototroph-heterotroph mixed-species biofilm at the stone/air interface

    Directory of Open Access Journals (Sweden)

    Federica eVilla

    2015-11-01

    Full Text Available Recent scientific investigations have shed light on the ecological importance and physiological complexity of subaerial biofilms (SABs inhabiting lithic surfaces. In the field of sustainable cultural heritage (CH preservation, mechanistic approaches aimed at investigation of the spatiotemporal patterns of interactions between the biofilm, the stone, and the atmosphere are of outstanding importance. However, these interactions have proven difficult to explore with field experiments due to the inaccessibility of samples, the complexity of the ecosystem under investigation and the temporal resolution of the experiments.To overcome these limitations, we aimed at developing a unifying methodology to reproduce a fast-growing, phototroph-heterotroph mixed species biofilm at the stone/air interface. Our experiments underscore the ability of the dual-species SAB model to capture functional traits characteristic of biofilms inhabiting lithic substrate such as: i microcolonies of aggregated bacteria; ii network like structure following surface topography; iii cooperation between phototrophs and heterotrophs and cross feeding processes; iv ability to change the chemical parameters that characterize the microhabitats; v survival under desiccation and vi biocide tolerance. With its advantages in control, replication, range of different experimental scenarios and matches with the real ecosystem, the developed model system is a powerful tool to advance our mechanistic understanding of the stone-biofilm-atmosphere interplay in different environments.

  5. Ultrasonographic diagnosis of ureteral stones: Accuracy and factors influencing on diagnostic sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Park, Young Mi; Han, Sang Seok; Chang, Seung Kuk; Joo, Sang Hoo; Lee, Jeong Sik; Eun, Choong Ki [Pusan Paik Hospital, Inje University College of Medicine, Pusan (Korea, Republic of)

    1999-12-15

    To determine the accuracy of ultrasonographic diagnosis in patients with clinically suspected ureteral stones and to evaluate the factors influencing on the diagnostic sensitivity for the detection of ureteral stone. The patients (115 cases) with proven presence or absence of ureteral stones were included in the study. At first, both sided kidney and proximal ureters were examined on each decubitus position and then middle ureters were done if proximal ureters were visualized. On the supine view, distal ureters and UVJ were scanned through the acoustic window of the filled bladder. KUB (20 cases), IVU (62 cases), AGP (7 cases), RGP (3 cases), ESWL (9 cases), CT (9 cases), and patients' history of spontaneous passage of stones (5 cases) were included as confirmation methods. The sensitivity, specificity, and accuracy of the ultrasonographic diagnosis of ureteral stones were calculated and the factors influencing on the sensitivity on the focus of the position and size of ureteral stone, visibility of ureter, the presence or absence of renal stone and hydronephrosis were analyzed. Of 82 cases with proven ureteral stone, 72 cases were revealed on ultrasonography and there was one false positive examination among 33 cases with proven absence of ureteral stone. The overall diagnostic accuracy was 90%. The ultrasonographic detection rates of ureteral stones as correlated with their locations were 83% (24/29), 100% (11/11), 80% (16/20), and 100% (21/21) of each group of proximal, middle, distal ureter, and UVJ stones. Of 61 stones, those as correlated with their sizes, were 82% (37/45) and 94% (15/16) of each group less than 10 mm and more than 11 mm. Those as correlated with the presence or absence of ureteral visualization on ultrasonography were 92% (69/75) and 43% (3/7) of each group. Those as correlated with presence of absence of renal stones were 85% (41/48) and 91% (31/34) of each group. Those as correlated with presence or absence of hydronephrosis were 89

  6. Grasping the Formless in Stones

    DEFF Research Database (Denmark)

    Aktor, Mikael

    2017-01-01

    and the repertoire of used forms. The chapter demonstrates that neither anthropomorphic perceptions nor the agency of the stone material alone make up the ritual aesthetics in which the stones are involved. Rather, applying concepts from landscape phenomenology and cognitive theories including the role of material...

  7. Water retention properties of Callovo-Oxfordian clay-stone

    International Nuclear Information System (INIS)

    Wan, Min; Delage, Pierre; Tang, Anh Minh; GATMIRI, Behrouz

    2012-01-01

    Document available in extended abstract form only. Many investigations were carried out on the Callovo-Oxfordian (COx) clay-stone that has been selected by the French radioactive waste management agency (ANDRA) as a potential host rock for high level radioactive waste disposal at great depth. Various authors demonstrated the significant water sensitivity of clay-stones. Some cracks generated by desaturation have been observed in the Tournemire URL (France) excavated in clay-stone. By carrying out some ESEM (environmental scanning electron microscope) observations on COx clay-stone samples submitted to cyclic changes in relative humidity, Montes et al. (2004) evidenced the water sensitivity of the clay fraction, with significant successive openings and closures of cracks and pores. Hysteresis effects have been observed in the water retention curve, in the ultrasonic velocity evolution and in the strain changes induced by hydration cycles on COx samples submitted to controlled relative humidities by Pham et al., (2007). Better knowledge of the mechanism of desaturation of the clay-stone is necessary to further understand the changes in hydro-mechanical properties of the excavation damaged zone (EDZ) that becomes significantly de-saturated all around the galleries because of ventilation. In this framework, a detailed study of the water retention properties of the COx clay-stone was carried out i) to complete existing observations with respect to volume changes under suction cycles and ii) to determine the main drying and wetting curves so as to better investigate hysteresis effects in the water retention curve.. Particular attention was paid to the characterization of the initial state in the laboratory (where samples are provided unsaturated due to the combined effect of coring, storage and transportation) and to the volume changes and changes in degree of saturation along the main wetting and drying paths. The determination of the water retention properties was

  8. Getter Incorporation into Cast Stone and Solid State Characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Asmussen, Robert M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lawter, Amanda R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stephenson, John R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bowden, Mark E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Washton, Nancy M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Neeway, James J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Du, Yingge [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pearce, Carolyn I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Clayton, Ray E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Saslow, Sarah A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cordova, Elsa [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, Nikolla [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-28

    Washington River Protection Solutions (WRPS) is collecting relevant available data on waste forms for use as a supplemental immobilization technology, to provide the additional capacity needed to treat low-activity waste (LAW) in Hanford Site tanks and complete the tank waste cleanup mission in a timely and cost-effective manner. One candidate supplemental waste form, fabricated using a low-temperature process, is a cementitious grout called Cast Stone. Cast Stone has been under investigation for this application at Pacific Northwest National Laboratory (PNNL) since initial screening tests in FY13. This report is the culmination of work to lower the diffusivities of Tc and I from Cast Stone using getters. Getters are compounds added to a system designed to selectively sequester a species of interest to provide increased stability to the species. The work contained within this report is related to waste form development and testing, and does not directly support the 2017 integrated disposal facility (IDF) performance assessment. However, this work contains valuable information which may be used in performance assessment maintenance past FY17, and in future waste form development. This report on performance characterization of Tc and I getters in Cast Stone fabricated with simulated LAW covers several areas of interest and major findings to WRPS: investigating performance of potassium metal sulfide (KMS-2-SS) and tin (II) apatite (Sn-A) as Tc getters when incorporated into Cast Stone; investigating performance of silver exchanged zeolite (Ag-Z) and argentite (Arg) as I getters when incorporated into Cast Stone; utilizing sequential addition of Tc and I getters to overcome any deleterious interactions between the getters in solution; determining, for the first time, Tc distribution within the cured Cast Stone and its evolution during leaching; and performing solid state characterization of getters and Cast Stone samples to support leach test findings and develop a

  9. Comparison of Different Methods of Denim Stone Washing by Pumice Stone, Acid Cellulases and Neutral Cellulases

    Directory of Open Access Journals (Sweden)

    M. Montazer

    2007-10-01

    Full Text Available Denim is a casual garment normally used by young people and extremely influential in shaping the fashion industry. Among various garments, these garments are subjected to innovations. This work is an attempt to compare the different methods of stone washing using pumice stones, acid cellulases and neutral cellulases or in combination of these methods. The effects of different processing conditions on the garment are compared and reported. Color differences of samples are probed by reflective colorimeter on the front side as well as the backside and also the white pocket of the garment.The abrasion resistance, tensile strength and crease recovery angle of samples are also reported. The XRD spectra are used to calculate the crystalline degrees of the selected samples. Moreover, fiber surfaces of some treated samples have been observed by SEM. The results indicate that treatment of denim with pumice stone with equal weight of garment causes a small color differences. The addition of cellulases to the washing, however, accelerates the color fading. Also, lower staining observed on the white pocket when the garment was treated with cellulases. However, the neutralcellulases increase the garment fading and decrease the staining on the white pocket. It is also observed that pumice stone with cellulases damages the fabric surface, although it is of a minimal damage.

  10. Single-stage laparoscopic common bile duct exploration and cholecystectomy versus two-stage endoscopic stone extraction followed by laparoscopic cholecystectomy for patients with concomitant gallbladder stones and common bile duct stones: a randomized controlled trial.

    Science.gov (United States)

    Bansal, Virinder Kumar; Misra, Mahesh C; Rajan, Karthik; Kilambi, Ragini; Kumar, Subodh; Krishna, Asuri; Kumar, Atin; Pandav, Chandrakant S; Subramaniam, Rajeshwari; Arora, M K; Garg, Pramod Kumar

    2014-03-01

    The ideal method for managing concomitant gallbladder stones and common bile duct (CBD) stones is debatable. The currently preferred method is two-stage endoscopic stone extraction followed by laparoscopic cholecystectomy (LC). This prospective randomized trial compared the success and cost effectiveness of single- and two-stage management of patients with concomitant gallbladder and CBD stones. Consecutive patients with concomitant gallbladder and CBD stones were randomized to either single-stage laparoscopic CBD exploration and cholecystectomy (group 1) or endoscopic retrograde cholangiopancreatography (ERCP) for endoscopic extraction of CBD stones followed by LC (group 2). Success was defined as complete clearance of CBD and cholecystectomy by the intended method. Cost effectiveness was measured using the incremental cost-effectiveness ratio. Intention-to-treat analysis was performed to compare outcomes. From February 2009 to October 2012, 168 patients were randomized: 84 to the single-stage procedure (group 1) and 84 to the two-stage procedure (group 2). Both groups were matched with regard to demographic and clinical parameters. The success rates of laparoscopic CBD exploration and ERCP for clearance of CBD were similar (91.7 vs. 88.1 %). The overall success rate also was comparable: 88.1 % in group 1 and 79.8 % in group 2 (p = 0.20). Direct choledochotomy was performed in 83 of the 84 patients. The mean operative time was significantly longer in group 1 (135.7 ± 36.6 vs. 72.4 ± 27.6 min; p ≤ 0.001), but the overall hospital stay was significantly shorter (4.6 ± 2.4 vs. 5.3 ± 6.2 days; p = 0.03). Group 2 had a significantly greater number of procedures per patient (p gallbladder and CBD stones had similar success and complication rates, but the single-stage strategy was better in terms of shorter hospital stay, need for fewer procedures, and cost effectiveness.

  11. The composition of urinary stones in central sindh

    International Nuclear Information System (INIS)

    Memon, J.M.; Naqvi, S.Q.H.

    2014-01-01

    To determine chemical analysis of urinary stones of central sindh. Study design: Prospective and randomized study. Setting: Department of Surgery and Pathology of Peoples University of Medical and Health Sciences Nawabshah. Duration of study: Three years from May 2008 to May 2011. Material and Methods: Total 106 urolith patients who underwent open stone surgery were included in the study. EDTA Titration used for determination of calcium ions and determination of oxalate, phosphate, magnesium, ammonia, uric acid and cystine stones was carried out using spectrophotometer. These patients were asked to fill out a proforma with parameters of age, sex, radiological location of stone and chemical composition of surgically recovered stones. The stone analysis findings were reviewed and compared with other reported series Results: In this study 75(70.75%) patients were male and 31 (29.25%) female. Male to female ratio was of 2.41:1. The age ranged from 1 to 70 years with the mean of 22.69 years. The peak incidence of upper urinary tract stone in 20-30 years and lower urinary tract stones in both sexes was under 10 years. Anatomical location of stone showed 48(45.29%) renal, 13(12.26%) ureteric and 45(42.45%) bladder calculi. Chemical analysis revealed 56(52.8%) calcium oxalate, 7(6.6%) calcium phosphate, 11(10.3%) ammonium urate, 18(16.9%) uric acid, 13(12.2%) Sturvite and 1(0.9%) cystine calculi. Conclusion: It was concluded that urolithiasis is predominantly male disease. No age group was spared to stone disease. Calcium oxalate, uric acid, ammonium urate and mixed calculi are the main types in our study due to poor nutritional status, poverty and inadequate health facilities. Considering that knowledge of stone composition is of utmost importance to modify the incidence of urolithiasis. (author)

  12. Evaluation of stone volume distribution in renal collecting system as a predictor of stone-free rate after percutaneous nephrolithotomy: a retrospective single-center study.

    Science.gov (United States)

    Atalay, Hasan Anıl; Canat, Lutfi; Bayraktarlı, Recep; Alkan, Ilter; Can, Osman; Altunrende, Fatih

    2017-06-23

    We analyzed our stone-free rates of PNL with regard to stone burden and its ratio to the renal collecting system volume. Data of 164 patients who underwent PNL were analyzed retrospectively. Volume segmentation of renal collecting system and stones were done using 3D segmentation software with the images obtained from CT data. Analyzed stone volume (ASV) and renal collecting system volume (RCSV) were measured and the ASV-to-RCSV ratio was calculated after the creation of a 3D surface volume rendering of renal stones and the collecting system. Univariate and multivariate statistical analyses were performed to determine factors affecting stone-free rates; also we assessed the predictive accuracy of the ASV-to-RCSV ratio using the receiving operating curve (ROC) and AUC. The stone-free rate of PNL monotherapy was 53% (164 procedures).The ASV-to-RCSV ratio and calyx number with stones were the most influential predictors of stone-free status (OR 4.15, 95% CI 2.24-7.24, renal collecting system, which is calculated using the 3D volume segmentation method, is a significant determinant of the stone-free rate before PCNL surgery. It could be used as a single guide variable by the clinician before renal stone surgery to predict extra requirements for stone clearance.

  13. ROCK inhibition in models of neurodegeneration and its potential for clinical translation.

    Science.gov (United States)

    Koch, Jan Christoph; Tatenhorst, Lars; Roser, Anna-Elisa; Saal, Kim-Ann; Tönges, Lars; Lingor, Paul

    2018-04-03

    Neurodegenerative disorders like Parkinson's disease, Alzheimer's disease, or amyotrophic lateral sclerosis are affecting a rapidly increasing population worldwide. While common pathomechanisms such as protein aggregation, axonal degeneration, dysfunction of protein clearing and an altered immune response have been characterized, no disease-modifying therapies have been developed so far. Interestingly, a significant involvement of the Rho kinase (ROCK) signaling pathway has been described in all of these mechanisms making it a promising target for new therapeutic approaches. In this article, we first review current knowledge of the involvement of ROCK in neurodegenerative disorders and the utility of its inhibition as a disease-modifying therapy in different neurodegenerative disorders. After a detailed description of the biochemical characteristics of ROCK and its molecular interactors, differences of ROCK-expression under physiological and pathological conditions are compared. Next, different pharmacological and molecular-genetic strategies to inhibit ROCK-function are discussed, focusing on pharmacological ROCK-inhibitors. The role of the ROCK-pathway in cellular processes that are central in neurodegenerative disorders pathology like axonal degeneration, autophagy, synaptic and glial function is explained in detail. Finally, all available data on ROCK-inhibition in different animal models of neurodegenerative disorders is reviewed and first approaches for translation into human patients are discussed. Taken together, there is now extensive evidence from preclinical studies in several neurodegenerative disorders that characterize ROCK as a promising drug target for further translational research in neurodegenerative disorders. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Do You Have Symptoms of a Kidney Stone?

    Science.gov (United States)

    ... Or, the stone will be removed with treatment. Dogs, Cats, and Kidney Stones Humans aren't the only ones affected by kidney and bladder stones. Dogs, cats, and other animals can also have kidney ...

  15. Experimental investigation of the mechanical properties of Alfas stone

    Directory of Open Access Journals (Sweden)

    Konstas N. Kaklis

    2017-04-01

    Full Text Available This paper focuses on the experimental investigation of the mechanical properties of the Alfas natural building stone. Two series of uniaxial compression tests and indirect tensile tests (Brazilian tests were performed in order to determine the uniaxial compressive strength and the indirect tensile strength respectively. Different sets of cylindrical specimens and circular discs were prepared by varying their geometry in order to examine the size effect on the respective strength values. Also, the size effect was investigated with respect to the calculated intact rock modulus and Poisson’s ratio. All specimens were prepared by following the ISRM suggested methods and the load was applied using a stiff 1600 kN MTS hydraulic testing machine and a 500 kN load cell. Strain was measured using biaxial 0/90 stacked rosettes appropriately attached on each specimen.

  16. Which is better? Guy's versus S.T.O.N.E. nephrolithometry scoring systems in predicting stone-free status post-percutaneous nephrolithotomy.

    Science.gov (United States)

    Noureldin, Yasser A; Elkoushy, Mohamed A; Andonian, Sero

    2015-11-01

    The aim of the present study was to compare the accuracy of the Guy's and S.T.O.N.E. scoring systems in predicting percutaneous nephrolithotomy (PCNL) outcomes. After obtaining ethics approval, medical records of patients undergoing PCNL between 2009 and 2013 at a tertiary stone center were retrospectively reviewed. Guy's and S.T.O.N.E. scoring systems were calculated. Regression analysis and ROC curves were performed. A total of 185 PCNLs were reviewed. The overall stone-free rate was 71.9 % with a complication rate of 16.2 %. When compared to patients with residual fragments, stone-free patients had significantly lower Guy's grade (2.7 vs. 2; p stone-free status, OR 0.4 (p r = 0.3, p r = 0.4, p r = 0.2, p = 0.001 and r = 0.3, p stone-free status. Other factors not included in either scoring system may need to be incorporated in the future to increase their accuracy.

  17. Predictions of outcomes of renal stones after extracorporeal shock wave lithotripsy from stone characteristics determined by unenhanced helical computed tomography: a multivariate analysis

    International Nuclear Information System (INIS)

    Wang, Li-Jen; Wong, Yon-Cheong; Chuang, Cheng-Keng; Chu, Sheng-Hsien; Chen, Chih-Shou; Chiang, Yang-Jen; See, Lai-Chu

    2005-01-01

    The aim of our study is to analyze the relationships between the characteristics of renal stones determined by unenhanced helical computed tomography (UHCT) and their outcomes after extracorporeal shock wave lithotripsy (ESWL) as well as to predict ESWL outcomes of renal stones by their UHCT characteristics with the use of multivariate analysis. During a 7-month period, 80 adult patients with renal stones underwent ESWL as well as UHCT both before and 3 months after ESWL. Of the 80 patients, 42 patients were classified as ESWL successes and 38 as ESWL failures based on their post-ESWL UHCT findings. For pre-ESWL UHCT, a stone number of more than 2 (P=0.0236), a maximal stone size of greater than 12 mm (P 3 (P 3 (P=0.0003), the presence of nonround/oval stones (P=0.0072) and a maximal stone density of more than 900 HU (P=0.0430) were statistically significant predictors of a failure outcome for ESWL. Thus, the analysis of stone characteristics of renal stones by UHCT is helpful in selecting appropriate patients undergoing ESWL for favorable outcomes and reduces the overall costs of the treatment of renal stones. (orig.)

  18. Locomotion of Stramonita haemastoma (Linnaeus (Gastropoda, Muricidae on a mixed shore of rocks and sand

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    Marcos G. Papp

    2001-03-01

    Full Text Available Mixed shores of rocks and sand are appropriate systems for the study of limitations that the isolation of rocks may impose for gastropods that typically inhabit rocky shores. We marked 52 Stramonita haemastoma (Linnaeus, 1767 snails on a mixed shore and found that 34 of them moved between rocks one to four times during 15 surveys in a period of 72 days. In the experiments, the snails moved on rock by continuous, direct, ditaxic, alternate undulations of the foot sole but on submerged sand they used slower arrhythmic discontinuous contractions of the foot sole. They switched between modes of locomotion in response to the type and topography of the substrate and possibly to water dynamics. In nature, snails moved between rocks forming aggregations where they oviposited. This may have masked other causes of movement, such as availability of prey. Most snails burrowed into the sand when the rocks became exposed during low tides. Further experiments are needed to explicitly address the possible causes of movements among rocks and burial.

  19. Frequency and factors effecting non clearance of lower pole renal stones

    International Nuclear Information System (INIS)

    Ullah, A.; Zubair, M.; Khan, N.; Malik, A.

    2015-01-01

    Renal stone disease is a major health hazard in Pakistan and extra-corporeal shockwave lithotripsy is one of comprehensive method used to treat these stones. The aim of this study is to determine the frequency of factors affecting the non-clearance of stone fragments of lower pole renal stone after extra corporeal shockwave lithotripsy. The study was done with the objective to determine the frequency the spatial anatomical factors which can influence the non-clearance of lower pole stone fragments after ESWL. Methods: One and nineteen (119) patients with lower pole renal stone less than 10 mm were subjected to maximum 3 sessions of extracorporeal shock wave lithotripsy. KUB radiographs, ultrasonography and intravenous urography were used as investigative tools for lower pole renal calyceal anatomy. X ray KUB and ultrasound were done after a week for clearance. Data was analysed with the help of SPSS version 10.0 and presented in the forms of tables and graphs. Results: There were 77 (64.71%) males and 42 (35.29%) females. Infundibulo-pelvic angle (IPA)>40 degree was present in 93 (78.15%), Infundibular length (IL) <22 mm in 107 (89.92%) and Infundibular width (IW) >4 mm was present in 100 (84.03%) patients. The frequency of stone non clearance was noted in 31 (26.05%). Infundibulo-pelvic angle (IPA)>40 degree (p=0.000), Infundibular length (IL)<22 mm (p=0.001) and Infundibular width (IW)>4 mm (p=0.046) were significant variables affecting stone clearance. Conclusion: The frequency of non-clearance of lower calyx of kidney stone is 26.05%. The clearance of fragments of the lower calyx kidney stones is affected by three spatial anatomical factors, i.e., Infundibulopelvic angle, Infundibular width and infundibular length. (author)

  20. Can sonography define the chemical composition of gall stones

    International Nuclear Information System (INIS)

    Frentzel-Beyme, B.; Faehndrich, R.; Arnan-Thiele, B.

    1983-01-01

    Eight sonographic patterns caused by gall stones are described. In an attempt to explain these different appearances, 62 stones were analysed chemically and physically. The chemical composition of the stones did not correlate with their sonographic pattern. Cholesterol stones cannot be recognised as such by sonography. The formation of an acoustic shadow depends largely on the position of the stone within the acoustic beam. It therefore follows that the examination must be done by keeping the focal plane of the transducer in proper relationship to the stone. (orig.) [de

  1. Gypsum accumulation on carbonate stone

    Science.gov (United States)

    McGee, E.S.; Mossotti, V.G.

    1992-01-01

    The accumulation of gypsum on carbonate stone has been investigated through exposure of fresh samples of limestone and marble at monitored sites, through examination of alteration crusts from old buildings and through laboratory experiments. Several factors contribute to gypsum accumulation on carbonate stone. Marble or limestone that is sheltered from direct washing by rain in an urban environment with elevated pollution levels is likely to accumulate a gypsum crust. Crust development may be enhanced if the stone is porous or has an irregular surface area. Gypsum crusts are a surficial alteration feature; gypsum crystals form at the pore opening-air interface, where evaporation is greatest.

  2. Role of alpha-1 blocker in expulsion of stone fragments after extracorporeal shock wave lithotripsy for renal stones

    International Nuclear Information System (INIS)

    Pirzada, A.J.; Anwar, A.; Javed, A.; Memon, I.; Mohammad, A.

    2011-01-01

    Background: Renal stone disease is a significant and worldwide health problem. Recent advances in stone management have allowed kidney stones to be treated using extracorporeal shock wave lithotripsy (ESWL), uretero-renoscopy (URS), and percutaneous nephrostolithotomy (PCNL). Recently, medical expulsion therapy (MET) has been investigated as a supplement to observation in an effort to improve spontaneous stone passage rates. Patients and Methods: This study was a randomized, controlled, prospective study to determine whether the administration of Alpha-1-adrenergic receptor antagonists as an adjunctive medical therapy, increases the efficacy of ESWL to treat renal stones. Sixty patients with renal stones of 0.5-1.5 Cm in size (average size 1.2 Cm) were included in this study underwent ESWL followed by administration of Alpha-1-adrenergic receptor antagonists at department of Urology Liaquat National Hospital Karachi from Feb 2008 to Sept 2008. This was a comparative study and patients were divided into two groups. In group A patients received conventional treatment Diclofenac sodium, Anti Spasmodic (Drotaverine HCl) as required and Proton Pump inhibitor (Omeprazole 20 mg) once daily after shock wave lithotripsy. In group B patients received alpha-1 blocker, Alfuzosin HCl 5 mg twice daily in addition to conventional treatment. All patients were instructed to drink a minimum of 2 litres water daily. Ultrasound guided Dornier Alpha Impact Lithotripter was utilised for shock wave lithotripsy. Results: Of the 60 patients, 76.7% of those receiving Alfuzosin and 46.7% of controls had achieved clinical success at 1 month (p=0.01). The mean cumulative diclofenac dose was 485 mg per patient in the Alfuzosin group and 768 mg per patient in the control group (p=0.002). This difference was statistically significant. Conclusion: Alfuzosin therapy as an adjunctive medical therapy after ESWL is more effective than lithotripsy alone for the treatment of patients with large renal

  3. Quantifying the Use of stones in the stone age Fireplaces of Estonia

    OpenAIRE

    Sikk, Kaarel

    2017-01-01

    Fireplaces and burnt stones related to them are common features found at Stone Age settlement sites. Although information about them is present in archaeological reports and also available in publications, there has been no general research done regarding combustion features specifically. The purpose of this study was to fill the gap of relevant research and to test the hypothesis that the structural features of fireplaces reveal information on the subsistence model of settlements.The study is b...

  4. Pattern of urinary tract stone diseases in Mekelle, Ethiopia.

    Science.gov (United States)

    Alemu, Mekonnen Hagos

    2008-07-01

    To evaluate and analyze the pattern of patients with urinary stone diseases admitted to Mekelle Hospital. Between Sept 2003 to Sept 2006, 102 patients with urinary stone disease were admitted to Mekelle Hospital. In this descriptive retrospective audit, case notes were obtained from medical record office and were analyzed for age, sex, localization of the stone disease and the geographic back grounds. Seventy six (74.5%) of the patients were males and 26 (25.5%) were females. There were 102 (13.6%) cases of urinary stone disease admitted to Mekelle Hospital out of 750 total admissions for urological disease for intervention in the surgical ward during the study period. There were 76 (74.5%) males and 26 (25.5%) females and the sex ratio was (M: F: 2.9:1). Most (46.0%) of the urinary stone diseases were between 0-19 year age group both in males and females. The median age was 20 years (range from 2-74 years) and the mean was 25.4 years. Urinary bladder stones were the most common urinary tract stone diseases accounting for 47 (46.0%) followed by renal stones 29 (28.4%), ureteric 16 (15.6%) and urethral 10 (9.8%) stone disease; in that order of frequency. The geographical back ground of the patients with urinary tract stone disease in this report has shown that majorities (53.7%) were from urban and the remaining (44.2%) were from the rural areas. This study has depicted that urinary bladder stone diseases are the most common stone diseases affecting the younger age group. Since this is an institutional based study, it underestimates the magnitude and the pattern of urinary stone diseases at all level. Nevertheless, the audit provides useful information on the socio demographic variables, localization and the geographic back ground of the patients.

  5. Urinary stone composition in Oman: with high incidence of cystinuria.

    Science.gov (United States)

    Al-Marhoon, Mohammed S; Bayoumi, Riad; Al-Farsi, Yahya; Al-Hinai, Abdullhakeem; Al-Maskary, Sultan; Venkiteswaran, Krishna; Al-Busaidi, Qassim; Mathew, Josephkunju; Rhman, Khalid; Sharif, Omar; Aquil, Shahid; Al-Hashmi, Intisar

    2015-06-01

    Urinary stones are a common problem in Oman and their composition is unknown. The aim of this study is to analyze the components of urinary stones of Omani patients and use the obtained data for future studies of etiology, treatment, and prevention. Urinary stones of 255 consecutive patients were collected at the Sultan Qaboos University Hospital. Stones were analyzed by Fourier transform infrared spectrophotometer. The biochemical, metabolic, and radiological data relating to the patients and stones were collected. The mean age was 41 years, with M:F ratio of 3.7:1. The common comorbidities associated with stone formation were hypertension; diabetes, benign prostate hyperplasia; urinary tract infection; obesity; and atrophic kidney. The common presentation was renal colic and flank pain (96%). Stones were surgically retrieved in 70% of patients. Mean stone size was 9 ± 0.5 mm (range 1.3-80). Stone formers had a BMI ≥ 25 in 56% (P = 0.006) and positive family history of stones in 3.8%. The most common stones in Oman were as follows: Calcium Oxalates 45% (114/255); Mixed calcium phosphates & calcium oxalates 22% (55/255); Uric Acid 16% (40/255); and Cystine 4% (10/255). The most common urinary stones in Oman are Calcium Oxalates. Overweight is an important risk factor associated with stone formation. The hereditary Cystine stones are three times more common in Oman than what is reported in the literature that needs further genetic studies.

  6. The demonstration of gall stones by sonography and radiography

    International Nuclear Information System (INIS)

    Gladisch, R.; Deininger, H.K.; Staedtische Kliniken Darmstadt

    1983-01-01

    Eighty-seven unselected gall stones were examined radiologically and by ultrasound in vitro. No relationship of diagnostic value could be established between the amount of calcification and stone demonstration, the sonogram being influenced by the size of the stone, its surface contour and its position in the ultrasound beam. Sonography is therefore not suitable for selecting those patients on whom litholysis could be carried out. Sonography appears to be useful only in a negative way by establishing the exact size of the concretion. (orig.) [de

  7. Mold attack on frescoes and stone walls of Gradac monastery

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    Stupar Miloš Č.

    2011-01-01

    Full Text Available Microfungi can colonize stone surfaces and form sub-aerial biofilms which can lead to biodeterioration of historic monuments. In this investigation samples for mycological analyses were collected from stone material with visible alteration on stone walls of Gradac monastery exterior. The prevailing fungi found on stone walls were dematiaceous hyphomycetes with melanized hyphae and reproductive structures (Alternaria, Aureobasidium, Cladosporium and Epicoccum species. The frescoes inside the monastery building were also analyzed for the presence of mycobiota. The predominant fungi found on frescoes were osmophilic species from genera Aspergillus and Penicillium. The significant result is identification of human pathogen species Aspergillus fumigatus on frescoes.

  8. Effectiveness of Treatment Modalities on Kidney Stone Recurrence.

    Science.gov (United States)

    Zisman, Anna L

    2017-10-06

    Nephrolithiasis is highly prevalent across all demographic groups in the Western world and beyond, and its incidence rates are rising. In addition to the morbidity of the acute event, stone disease often becomes a lifelong problem that requires preventative therapy to diminish ongoing morbidity. Across the majority of stone types, increased fluid intake and targeted dietary modifications are mainstays of therapy. Specific dietary interventions associated with reduced calcium stone risk include adequate dietary calcium intake and restriction of sodium, protein, and oxalate intake, among others. Pharmaceutical therapy may be required if lifestyle changes are insufficient to minimize risk of stone recurrence, and must be targeted to the specific metabolic abnormalities portending risk for a given patient. Therapeutic options for idiopathic calcium stone disease include thiazides, citrate salts, and uric acid-lowering agents. Alkali salts are also the treatment of choice for uric acid stone disease. Management of struvite stone disease is largely surgical, but acetohydroxamic acid is a proven second line therapy. Cystinuria requires lifestyle modifications and may call for thiol-binding agents. Significant heterogeneity of the clinical population with stone disease has previously limited opportunities for large randomized controlled trials. However, as clinical phenotypes and genotypes are increasingly clarified, there are mounting opportunities for targeted randomized controlled trials in stone prevention. In the meantime, the currently available evidence for both lifestyle and pharmacologic interventions is reviewed herein. Copyright © 2017 by the American Society of Nephrology.

  9. Gaussian Multiscale Aggregation Applied to Segmentation in Hand Biometrics

    Directory of Open Access Journals (Sweden)

    Gonzalo Bailador del Pozo

    2011-11-01

    Full Text Available This paper presents an image segmentation algorithm based on Gaussian multiscale aggregation oriented to hand biometric applications. The method is able to isolate the hand from a wide variety of background textures such as carpets, fabric, glass, grass, soil or stones. The evaluation was carried out by using a publicly available synthetic database with 408,000 hand images in different backgrounds, comparing the performance in terms of accuracy and computational cost to two competitive segmentation methods existing in literature, namely Lossy Data Compression (LDC and Normalized Cuts (NCuts. The results highlight that the proposed method outperforms current competitive segmentation methods with regard to computational cost, time performance, accuracy and memory usage.

  10. Extracorporeal Shockwave Lithotripsy of Primary Intrahepatic Stones

    Science.gov (United States)

    Kim, Myung Hwan; Lee, Sung Koo; Min, Young Il; Lee, Mun Gyu; Sung, Kyu Bo; Cho, Kyung Sik; Lee, Sung Gyu; Min, Pyung Chul

    1992-01-01

    Extracorporeal shockwave lithothripsy (ESWL) was performed in intrahepatic stone patients (n = 18) by Dornier MPL 9,000 with ultrasound guidance. The patients had T-tube (n = 9) or percutaneous transhepatic biliary drainge tube (n = 9). Average treatment session was four and shock-wave numbers were in the range of 3,064 to 12,000 (average 6,288 shocks). Intrahepatic stones were removed completely in 16 patients over a 3 month period by ESWL and combined stone extraction maneuver such as cholangioscopic or interventional radiologic method. Extracorporeal shockwave lithothripsy was very helpful in facilitating extraction of stones in unfavorable locations or located above the severe stricture. In summary, extracorporeal Shockwave lithotripsy, followed by percutaneous stone extraction, will provide an improvement in the success rate and duration of treatment required for complete removal of primary hepatolithiasis. PMID:1477027

  11. Efficacy of the lithotripsy in treating lower pole renal stones.

    Science.gov (United States)

    Cui, Helen; Thomee, Eeke; Noble, Jeremy G; Reynard, John M; Turney, Benjamin W

    2013-06-01

    Use of extracorporeal lithotripsy is declining in North America and many European countries despite international guidelines advocating it as a first-line therapy. Traditionally, lithotripsy is thought to have poor efficacy at treating lower pole renal stones. We evaluated the success rates of lithotripsy for lower pole renal stones in our unit. 50 patients with lower pole kidney stones ≤15 mm treated between 3/5/11 and 19/4/12 were included in the study. Patients received lithotripsy on a fixed-site Storz Modulith SLX F2 lithotripter according to a standard protocol. Clinical success was defined as stone-free status or asymptomatic clinically insignificant residual fragments (CIRFs) ≤3 mm at radiological follow-up. The mean stone size was 7.8 mm. The majority of stones (66 %) were between 5 and 10 mm. 28 % of stones were between 10 and 15 mm. For solitary lower pole stones complete stone clearance was achieved in 63 %. Total stone clearance including those with CIRFs was achieved in 81 % of patients. As expected, for those with multiple lower pole stones the success rates were lower: complete clearance was observed in 39 % and combined clearance including those with CIRFs was 56 %. Overall, complete stone clearance was observed in 54 % of patients and clearance with CIRFs was achieved in 72 % of patients. Success rate could not be attributed to age, stone size or gender. Our outcome data for the treatment of lower pole renal stones (≤15 mm) compare favourably with the literature. With this level of stone clearance, a non-invasive, outpatient-based treatment like lithotripsy should remain the first-line treatment option for lower pole stones. Ureteroscopy must prove that it is significantly better either in terms of clinical outcome or patient satisfaction to justify replacing lithotripsy.

  12. Utility of Flexible Ureterorenoscopy and Laser Lithotripsy in the Treatment of Multiple Intrarenal Stones

    Directory of Open Access Journals (Sweden)

    Hasan Yılmaz

    2017-09-01

    Full Text Available Objective: We aimed to determine the safety and efficacy of flexible ureterorenoscopy and Holmium laser lithotripsy in treating multiple intrarenal stones. Materials and Methods: We identified 32 consecutive patients with multiple intrarenal stones who underwent flexible ureterorenoscopy and/or laser lithotripsy performed by a single surgeon. Informed consent was obtained from all participants before treatment. Each patient was evaluated in terms of stone location, stone number, stone size, stone burden (cumulative stone length, body mass index, operative time, stone-free rate, and perioperative complications. Results: The median age of the patients was 38 years [interquartile range (IQR, 34.25-52.00]. The patients had a total of 75 intrarenal calculi. The average number of stones per patient was 2.50 (IQR, 2.0-3.0. The median total stone burden per patient was 23.0 mm (IQR, 19.0-28.0 mm. Twenty-one patients (65.5% had stone burdens >20 mm, and 11 (34.5% had burdens ≤20 mm. The overall final stone-free rate was 78.1%. The stone-free rates for patients with stone burdens ≤20 mm and >20 mm were 81.8% (9/11 and 76.2% (16/21, respectively (p=0.544. A perioperative complication (urinary leakage occurred in one patient. Postoperative complications were recorded in four (12.5% patients; a urinary tract infection in one, pain requiring parenteral medication in two, and hematuria in one. Conclusion: Flexible ureterorenoscopy combined with laser lithotripsy may be an effective treatment option for patients with multiple intrarenal stones; we noted only a few minor complications. The success rate was higher in patients with stone burdens ≤20 mm.

  13. Can Hounsfield Unit Value Predict Type of Urinary Stones?

    Directory of Open Access Journals (Sweden)

    Alper Gok

    2014-03-01

    Full Text Available Aim: Aim of this study is to determine the role of Hounsfield unit (HU in predicting results of stone analysis. Material and Method: This study included 199 patients to whom percutaneous nephrolithotomy (PNL procedures were applied between January 2008 and May 2011 in our clinic. Before the procedure HU values of kidney stones were measured using non-contrast computed tomography. After the operation, obtained stone samples were analysed using X-ray diffraction technique. HU values were compared with stone analysis results. Results: Stone analysis revealed eight different stone types. Distribution of stone types and HU value ranges were as follows: 85% calcium oxalate monohydrate, 730-1130 HU; 38% calcium oxalate dihydrate, 510-810 HU; 21% uric acid, 320-550 HU; 23% struvite, 614-870 HU; 7% calcium hydrogene phosphate, 1100-1365 HU; 3% cystine, 630-674 HU; 15% mixed uric acid plus calcium oxalate, 499-840 HU; and 7% mixed cystine plus calcium phosphate, 430-520 HU. HU values of all stone types ranged between 320 and 1365. There was a statistically significant relation between HU values of uric acid and non uric acid stones (p

  14. Natural Stone Cluster and Valorpedra Association in Portugal: Collective efficiency, promotion and marketing strategies in the appreciation of the Dimension Stones production chain in Portugal

    OpenAIRE

    Lopes, Luís; Peres, Marta; Cristo, Nelson; Bonito, Nuno; Palma, Filipe; Goulão, Miguel

    2014-01-01

    The Natural Stone Cluster recognition by the Portuguese government resulted in the establishment of Valorpedra Association (VAPE). This national recognition allow development and increase competitiveness of the Dimension Stone Sector for which specific funds were available. The implemented measures potentiated networking among enterprises and development of partnership projects. VAPE is a nonprofit association that manages and promotes Natural Stone Cluster, seeking a Strategy for Collecti...

  15. The Guy's stone score--grading the complexity of percutaneous nephrolithotomy procedures.

    Science.gov (United States)

    Thomas, Kay; Smith, Naomi C; Hegarty, Nicholas; Glass, Jonathan M

    2011-08-01

    To report the development and validation of a scoring system, the Guy's stone score, to grade the complexity of percutaneous nephrolithotomy (PCNL). Currently, no standardized method is available to predict the stone-free rate after PCNL. The Guy's stone score was developed through a combination of expert opinion, published data review, and iterative testing. It comprises 4 grades: grade I, solitary stone in mid/lower pole or solitary stone in the pelvis with simple anatomy; grade II, solitary stone in upper pole or multiple stones in a patient with simple anatomy or a solitary stone in a patient with abnormal anatomy; grade III, multiple stones in a patient with abnormal anatomy or stones in a caliceal diverticulum or partial staghorn calculus; grade IV, staghorn calculus or any stone in a patient with spina bifida or spinal injury. It was assessed for reproducibility using the kappa coefficient and validated on a prospective database of 100 PCNL procedures performed in a tertiary stone center. The complications were graded using the modified Clavien score. The clinical outcomes were recorded prospectively and assessed with multivariate analysis. The Guy's stone score was the only factor that significantly and independently predicted the stone-free rate (P = .01). It was found to be reproducible, with good inter-rater agreement (P = .81). None of the other factors tested, including stone burden, operating surgeon, patient weight, age, and comorbidity, correlated with the stone-free rate. The Guy's stone score accurately predicted the stone-free rate after PCNL. It was easy to use and reproducible. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Evidence Report: Risk of Renal Stone Formation

    Science.gov (United States)

    Sibonga, Jean D.; Pietrzyk, Robert

    2017-01-01

    The formation of renal stones poses an in-flight health risk of high severity, not only because of the impact of renal colic on human performance but also because of complications that could potentially lead to crew evacuation, such as hematuria, infection, hydronephrosis, and sepsis. Evidence for risk factors comes from urine analyses of crewmembers, documenting changes to the urinary environment that are conducive to increased saturation of stone-forming salts, which are the driving force for nucleation and growth of a stone nidus. Further, renal stones have been documented in astronauts after return to Earth and in one cosmonaut during flight. Biochemical analysis of urine specimens has provided indication of hypercalciuria and hyperuricemia, reduced urine volumes, and increased urine saturation of calcium oxalate and calcium phosphate. A major contributor to the risk for renal stone formation is bone atrophy with increased turnover of the bone minerals. Dietary and fluid intakes also play major roles in the risk because of the influence on urine pH (more acidic) and on volume (decreased). Historically, specific assessments on urine samples from some Skylab crewmembers indicated that calcium excretion increased early in flight, notable by day 10 of flight, and almost exceeded the upper threshold for normal excretion (300mg/day in males). Other crewmember data documented reduced intake of fluid and reduced intake of potassium, phosphorus, magnesium, and citrate (an inhibitor of calcium stone formation) in the diet. Hence, data from both short-duration and long-duration missions indicate that space travel induces risk factors for renal stone formation that continue to persist after flight; this risk has been documented by reported kidney stones in crewmembers.

  17. Alkali aggregate reactivity in concrete structures in western Canada

    International Nuclear Information System (INIS)

    Morgan, D.R.; Empey, D.

    1989-01-01

    In several regions of Canada, particularly parts of Ontario, Quebec and the Maritime Provinces, research, testing and evaluation of aged concrete structures in the field has shown that alkali aggregate reactivity can give rise to pronounced concrete deterioration, particularly in hydraulic structures subjected to saturation or alternate wetting and drying such as locks, dams, canals, etc. Concrete deterioration is mainly caused by alkali-silica reactions and alkali-carbonate reactions, but a third type of deterioration involves slow/late expanding alkali-silicate/silica reactivity. The alkalies NaOH and KOH in the concrete pore solutions are mainly responsible for attack on expansive rocks and minerals in concrete. Methods for evaluating alkali-aggregate reaction potential in aggregates, and field and laboratory methods for detecting deterioration are discussed. Examples of alkali-aggregate reactions in structures is western Canada are detailed, including a water reservoir at Canadian Forces Base Chilliwack in British Columbia, the Oldman River diversion and flume, the Lundbreck Falls Bridge, and the St Mary's Reservoir spillway, all in southern Alberta. Mitigative measures include avoidance of use of suspect aggregates, but if this cannot be avoided it is recommended to keep the total alkalies in the concrete as low as possible and minimize opportunities for saturation of concrete by moisture. 16 refs., 19 figs., 1 tab

  18. Daily Cycle of Air Temperature and Surface Temperature in Stone Forest

    Science.gov (United States)

    Wang, K.; Li, Y.; Wang, X.; Yuan, M.

    2013-12-01

    Urbanization is one of the most profound human activities that impact on climate change. In cities, where are highly artificial areas, the conflict between human activity and natural climate is particularly prominent. Urban areas always have the larger area of impervious land, the higher consumption of greenhouse gases, more emissions of anthropogenic heat and air pollution, all contribute to the urban warming phenomena. Understanding the mechanisms causing a variety of phenomena involved in the urban warming is critical to distinguish the anthropogenic effect and natural variation in the climate change. However, the exact dynamics of urban warming were poorly understood, and effective control strategies are not available. Here we present a study of the daily cycle of air temperature and surface temperature in Stone Forest. The specific heat of the stones in the Stone Forest and concrete of the man-made structures within the cities are approximate. Besides, the height of the Stone Forest and the height of buildings within the city are also similar. As a scenic area, the Stone Forest is being preserved and only opened for sightseeing. There is no anthropogenic heat, as well air pollution within the Stone Forest. The thermal environment in Stone Forest can be considered to be a simulation of thermal environment in the city, which can reveal the effect of man-made structures on urban thermal environment. We conducted the field studies and numerical analysis in the Stone Forest for 4 typical urban morphology and environment scenarios, including high-rise compact cities, low-rise sparse cities, garden cities and isolated single stone. Air temperature and relative humidity were measured every half an hour in 15 different locations, which within different spatial distribution of stones and can represent the four urban scenarios respectively. At the same time, an infrared camera was used to take thermal images and get the hourly surface temperatures of stones and

  19. INCREASING DEMANDS FOR NATURAL STONES USAGE AROUND THE WORLD

    Directory of Open Access Journals (Sweden)

    HASAN ÜÇPIRTI

    1998-12-01

    Full Text Available Due to great demands in construction business, the stone industry has been growing very fast around the world. In fact, the technological iınproveınents on the ınachinery of marble and granite processing plant and quarry in recent years gives impulse to the stone business. According to studies reported� there are recognizable increments on both productions and constructions. Natural stones become driving forces in tl1e countries economy. In this study� so ın e statistical nuınbers for productions and consumption of natural stones will be presented in a base of countries that strongly involve in stone business. The importance of the econoınical impacts of natural stone on countries econoıny wiJI be emphasized. Then, the future of natural stones and its business will be discussed

  20. Significant effect of grain size distribution on compaction rates in granular aggregates

    NARCIS (Netherlands)

    Niemeijer, André|info:eu-repo/dai/nl/370832132; Elsworth, Derek; Marone, Chris

    2009-01-01

    We investigate the role of pressure solution in deformation of upper- to mid-crustal rocks using aggregates of halite as a room temperature analog for fluid-assisted deformation processes in the Earth's crust. Experiments evaluate the effects of initial grain size distribution on macroscopic

  1. Imaging-based logics for ornamental stone quality chart definition

    Science.gov (United States)

    Bonifazi, Giuseppe; Gargiulo, Aldo; Serranti, Silvia; Raspi, Costantino

    2007-02-01

    Ornamental stone products are commercially classified on the market according to several factors related both to intrinsic lythologic characteristics and to their visible pictorial attributes. Sometimes these latter aspects prevail in quality criteria definition and assessment. Pictorial attributes are in any case also influenced by the performed working actions and the utilized tools selected to realize the final stone manufactured product. Stone surface finishing is a critical task because it can contribute to enhance certain aesthetic features of the stone itself. The study was addressed to develop an innovative set of methodologies and techniques able to quantify the aesthetic quality level of stone products taking into account both the physical and the aesthetical characteristics of the stones. In particular, the degree of polishing of the stone surfaces and the presence of defects have been evaluated, applying digital image processing strategies. Morphological and color parameters have been extracted developing specific software architectures. Results showed as the proposed approaches allow to quantify the degree of polishing and to identify surface defects related to the intrinsic characteristics of the stone and/or the performed working actions.

  2. Reactions between rocks and the hydroxides of calcium, sodium and potassium: progress report no. 1

    International Nuclear Information System (INIS)

    Van Aardt, J.H.P.; Visser, S.

    1982-01-01

    The reaction between the hydroxides of calcium, sodium and potassium, and clay minerals, feldspars, and some rocks (aggregates for use in concrete) was investigated. The reaction products were examined by means of x-ray diffraction and chemical analysis. The solid reaction products identified were hydrated calcium silicates,hydrated calcium aluminates, and hydrated calcium alumina silicates. It was found that, in the presence of water, calcium hydroxide liberated alkali into solution if the rocks and minerals contained alkali metals in their structure. Two crystalline hydrated sodium calcium silicates (12A and 16A) were prepared in the system Na 2 O-CaO-SiO 2 -H 2 O at 80 degrees Celsius. The one compound (12A) was also observed when sodium hydroxide plus calcium hydroxide and water reacted with silica- or silicate-containing rocks

  3. Exploring the techno-economic feasibility of mine rock waste utilisation in road works: The case of a mining deposit in Ghana.

    Science.gov (United States)

    Agyeman, Stephen; Ampadu, Samuel I K

    2016-02-01

    Mine rock waste, which is the rock material removed in order to access and mine ore, is free from gold processing chemical contaminants but presents a significant environmental challenge owing to the large volumes involved. One way of mitigating the environmental and safety challenges posed by the large volume of mine rock waste stockpiled in mining communities is to find uses of this material as a substitute for rock aggregates in construction. This article reports on a study conducted to evaluate the engineering properties of such a mine deposit to determine its suitability for use as road pavement material. Samples of mine rock waste, derived from the granitic and granodioritic intrusive units overlying the gold-bearing metavolcanic rock and volcano-clastic sediments of a gold mining area in Ghana, were obtained from three mine rock waste disposal facilities and subjected to a battery of laboratory tests to determine their physical, mechanical, geotechnical, geometrical and durability properties. The overall conclusion was that the mine rock waste met all the requirements of the Ghana Ministry of Transportation specification for use as aggregates for crushed rock subbase, base and surface dressing chippings for road pavements. The recommendation is to process it into the required sizes for the various applications. © The Author(s) 2015.

  4. A Case for Nebula Scale Mixing Between Non-Carbonaceous and Carbonaceous Chondrite Reservoirs: Testing the Grand Tack Model with Chromium Isotopic Composition of Almahata Sitta Stone 91A

    Science.gov (United States)

    Sanborn, M. E.; Yin, Q.-Z.; Goodrich, C. A.; Zolensky, M.; Fioretti, A. M.

    2017-01-01

    There is an increasing number of Cr-O-Ti isotope studies that show solar system materials are divided into two main populations, one carbonaceous chondrite (CC)-like and the other is non-carbonaceous (NC)-like, with minimal mixing attributed to a gap opened in the protoplanetary disk due to Jupiter's formation. The Grand Tack model suggests there should be large-scale mixing between S- and C-type asteroids, an idea supported by our recent work on chondrule (Delta)17O-e54Cr isotope systematics. The Almahata Sitta (AhS) meteorite provides a unique opportunity to test the Grand Tack model. The meteorite fell to Earth in October 2008 and has been linked to the asteroid 2008 TC3 which was discovered just prior to the fall of the AhS stones. The AhS meteorite is composed of up to 700 individual pieces with approx.140 of those pieces having some geochemical and/or petrologic studies. Almahata Sitta is an anomalous polymict ureilite with other meteorite components, including enstatite, ordinary, and carbonaceous chondrites with an approximate abundance of 70% ureilites and 30% chondrites. This observation has lead to the suggestion that TC3 2008 was a loosely aggregated rubble pile-like asteroid with the non-ureilite sample clasts within the rubble-pile. Due to the loosely-aggregated nature of AhS, the object disintegrated during atmospheric entry resulting in the weakly held clasts falling predominantly as individual stones in the AhS collection area. However, recent work has identified one sample of AhS, sample 91A, which may represent two different lithologies coexisting within a single stone. The predominate lithology type in 91A appears to be that of a C2 chondrite based on mineralogy but also contains olivine, pyroxene, and albite that have ureilite-like compositions. Previous Cr isotope investigations into AhS stones are sparse and what data is available show nearly uniform isotopic composition similar to that of typical ureilites with negative e54Cr values.

  5. Pathophysiology of kidney, gallbladder and urinary stones treatment with herbal and allopathic medicine: A review

    Directory of Open Access Journals (Sweden)

    Shashi Alok

    2013-12-01

    Full Text Available Medicinal plants have been known for millennia and are highly esteemed all over the world as a rich source of therapeutic agents for the prevention of various ailments. Today large number of population suffers from kidney stone, gall stone and urinary calculi. Stone disease has gained increasing significance due to changes in living conditions i.e. industrialization and malnutrition. Changes in prevalence and incidence, the occurrence of stone types and stone location, and the manner of stone removal are explained. Medicinal plants are used from centuries due to its safety, efficacy, cultural acceptability and lesser side effects as compared to synthetic drugs. The present article deals with measures to be adopted for the potential of medicinal plants in stone dissolving activity. The problem of urinary stones or calculi is a very ancient one and many remedies have been employed during the ages these stones are found in all parts of the urinary tract, the kidney, the ureters and the urinary bladder and may vary considerably in size. In the present article, an attempt has been made to emphasis on herbal option for urinary stone.

  6. Pathophysiology of kidney, gallbladder and urinary stones treatment with herbal and allopathic medicine: A review

    Science.gov (United States)

    Alok, Shashi; Jain, Sanjay Kumar; Verma, Amita; Kumar, Mayank; Sabharwal, Monika

    2013-01-01

    Medicinal plants have been known for millennia and are highly esteemed all over the world as a rich source of therapeutic agents for the prevention of various ailments. Today large number of population suffers from kidney stone, gall stone and urinary calculi. Stone disease has gained increasing significance due to changes in living conditions i.e. industrialization and malnutrition. Changes in prevalence and incidence, the occurrence of stone types and stone location, and the manner of stone removal are explained. Medicinal plants are used from centuries due to its safety, efficacy, cultural acceptability and lesser side effects as compared to synthetic drugs. The present article deals with measures to be adopted for the potential of medicinal plants in stone dissolving activity. The problem of urinary stones or calculi is a very ancient one and many remedies have been employed during the ages these stones are found in all parts of the urinary tract, the kidney, the ureters and the urinary bladder and may vary considerably in size. In the present article, an attempt has been made to emphasis on herbal option for urinary stone.

  7. Stone tools from locality Crkvine in Stubline

    Directory of Open Access Journals (Sweden)

    Antonović Dragana

    2011-01-01

    artifacts, which indicate the same primary sources of raw material. These sources were most probably used by population of the locality Kremenite njive in Barajevo and Šalitrena pećina in the vicinity of the Brežđe village, near Valjevo. Typology and raw material structure from Trench 5/2008 in Crkvine in a whole are in accordance with the general image of the ground stone industry in the final stage of the Vinča culture. Among the tools prevailed abrasive artifacts (grindstones, whetstone, pounders and querns, while ground-edge tools are significantly rare appearing only as adze or as extremely rare occurrences of chisle. Non-defined fragments are most abundant , at first place the flakes made of „ligth white stone“ representing half-fabricates of the polished stone industry. This implies that the production of tools from this raw material was local in character, possibly even organized within households. The habitants of this Late Vinča settlement, according to the raw material used for their massive tools, most probably have undertaken stone exploitation from quarries. Striving to select appropriate row material for making high quality querns, they discovered a greywacke deposit and used the same raw material for making other abrasive tools as well. The presence of other rock types indicates that alluvium material in the vicinity of the locality was possibly used, as well. The presence of abundant „light white stone“ artifacts confirms that the raw material was exploited from a narrow local area. Utilization of this type of raw material cannot be connected with the „ ligth white stone“ found on contemporaneous localities in the vicinity: magnesite was used in Vinča, diatomite on Ilića brdo, tuff in Crkvine near Mali Borak. It is most likely that each settlement exploited deposits of the given stone type in its immediate vicinity. The Late Vinča settlement in Crkvine had a surface of more than 16 ha, however, only a small area (in 2008 two trenches of

  8. Relationship Between Ureteral Jet Flow, Visual Analogue Scale, and Ureteral Stone Size.

    Science.gov (United States)

    Ongun, Sakir; Teken, Abdurrazak; Yılmaz, Orkun; Süleyman, Sakir

    2017-06-01

    To contribute to the diagnosis and treatment of ureteral stones by investigating the relationship between the ureteral jet flow measurements of patients with ureteral stones and the size of the stones and the patients' pain scores. The sample consisted of patients who presented acute renal colic between December 2014 and 2015 and from a noncontrast computed tomography were found to have a urinary stone. The ureteral jet flow velocities were determined using Doppler ultrasonography. The patients were all assessed in terms of stone size, localization and area, anteroposterior pelvis (AP) diameter, and visual analogue scale (VAS) scores. A total of 102 patients were included in the study. As the VAS score decreased, the peak jet flow velocity on the stone side increased, whereas the flow velocity on the other side, AP diameter, and stone area were reduced (P flow velocity was reduced and the AP diameter increased significantly (P flow was not observed in 17 patients on the stone side. A statistically significant difference was found between these patients and the remaining patients in terms of all parameters (P flow velocity of ureteral jet is low and with a severe level of pain or the peak flow velocity of ureteral jet cannot be measured, there is a low possibility of spontaneous passage and a high possibility of a large stone, and therefore the treatment should be started immediately. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Accuracy of endoscopic intraoperative assessment of urologic stone size.

    Science.gov (United States)

    Patel, Nishant; Chew, Ben; Knudsen, Bodo; Lipkin, Michael; Wenzler, David; Sur, Roger L

    2014-05-01

    Endoscopic treatment of renal calculi relies on surgeon assessment of residual stone fragment size for either basket removal or for the passage of fragments postoperatively. We therefore sought to determine the accuracy of endoscopic assessment of renal calculi size. Between January and May 2013, five board-certified endourologists participated in an ex vivo artificial endoscopic simulation. A total of 10 stones (pebbles) were measured (mm) by nonparticipating urologist (N.D.P.) with electronic calibers and placed into separate labeled opaque test tubes to prevent visualization of the stones through the side of the tube. Endourologists were blinded to the actual size of the stones. A flexible digital ureteroscope with a 200-μm core sized laser fiber in the working channel as a size reference was placed through the ureteroscope into the test tube to estimate the stone size (mm). Accuracy was determined by obtaining the correlation coefficient (r) and constructing an Altman-Bland plot. Endourologists tended to overestimate actual stone size by a margin of 0.05 mm. The Pearson correlation coefficient was r=0.924, with a p-valuestones (stones (≥4 mm), r=0.911 vs r=0.666. Altman-bland plot analysis suggests that surgeons are able to accurately estimate stone size within a range of -1.8 to +1.9 mm. This ex vivo simulation study demonstrates that endoscopic assessment is reliable when assessing stone size. On average, there was a slight tendency to overestimate stone size by 0.05 mm. Most endourologists could visually estimate stone size within 2 mm of the actual size. These findings could be generalized to state that endourologists are accurately able to intraoperatively assess residual stone fragment size to guide decision making.

  10. The Dora-Maira Unit (Italian Cottian Alps): a reservoir of ornamental stones locally and worldwide employed since Roman age

    Science.gov (United States)

    Borghi, Alessandro; Cadoppi, Paola; Antonella Dino, Giovanna

    2015-04-01

    The Dora-Maira is a geological unit belonging to the Penninic Domain of the Western Alps (NW Italy), which covers over 1000 km2 from the Susa to the Maira valleys, in the inner part of the Cottian Alps. It consists of different superposed complexes made of micaschists, fine-grained gneisses, quartzites, impure and dolomitic marbles, metabasites and various types of orthogneisses deriving from metamorphic transformation, during alpine orogeny, of a Palaeozoic upper continental crust and its Mesozoic carbonate cover. Thanks to the presence of different varieties of rocks, the Dora-Maira Unit can be considered as a reservoir of ornamental stones, locally employed, since Roman age, for military and religious buildings. Furthermore, these materials were used in Piedmont region for the construction of important historical palaces (17th and 18th centuries). Several varieties of gneisses, quartzites and marbles, exploited in the past and up to now, come from the Paleozoic basement. The most famous variety of gneiss is the so called "Luserna stone", a leucocratic gneiss characterized by a mylonitic fabric deriving from highly differentiated granitoids of Permian age. The first traces of Luserna Stone exploitation arise to the medieval age in the Pellice Valley). This material was widely employed in Turin, from Savoia kingdom period up to know. The very peculiar and precious application of Luserna stone were: Royal Palace and Venaria Reale Palace, Mole Antonelliana. Recently, it has been employed for the construction of Turin Metro stations (launched in 2006). Other varieties of orthogneisses, not yet exploited, are: Borgone and Vaie Stones, Villarfocchiardo and Cumiana Stones. They were used for the realization of the columns characterising the façade of several churches in Turin and in the piers of different bridges over the Po River. Another gneiss variety, with dioritic composition, is the Malanaggio Stone employed in the Fenestrelle Fortress. As for the palaeozoic

  11. Validating automated kidney stone volumetry in computed tomography and mathematical correlation with estimated stone volume based on diameter.

    Science.gov (United States)

    Wilhelm, Konrad; Miernik, Arkadiusz; Hein, Simon; Schlager, Daniel; Adams, Fabian; Benndorf, Matthias; Fritz, Benjamin; Langer, Mathias; Hesse, Albrecht; Schoenthaler, Martin; Neubauer, Jakob

    2018-06-02

    To validate AutoMated UroLithiasis Evaluation Tool (AMULET) software for kidney stone volumetry and compare its performance to standard clinical practice. Maximum diameter and volume of 96 urinary stones were measured as reference standard by three independent urologists. The same stones were positioned in an anthropomorphic phantom and CT scans acquired in standard settings. Three independent radiologists blinded to the reference values took manual measurements of the maximum diameter and automatic measurements of maximum diameter and volume. An "expected volume" was calculated based on manual diameter measurements using the formula: V=4/3 πr³. 96 stones were analyzed in the study. We had initially aimed to assess 100. Nine were replaced during data acquisition due of crumbling and 4 had to be excluded because the automated measurement did not work. Mean reference maximum diameter was 13.3 mm (5.2-32.1 mm). Correlation coefficients among all measured outcomes were compared. The correlation between the manual and automatic diameter measurements to the reference was 0.98 and 0.91, respectively (pvolumetry is possible and significantly more accurate than diameter-based volumetric calculations. To avoid bias in clinical trials, size should be measured as volume. However, automated diameter measurements are not as accurate as manual measurements.

  12. Sonography as an initial study in patients with suspected ureteral stone

    International Nuclear Information System (INIS)

    Lee, Jae Gue; Lim, Joo Won; Ko, Young Tae; Lee, Dong Ho; Lee, Hye Won; Oh, Joo Hyeong; Yoon, Yup; Lee, Sun Ju

    1999-01-01

    To evaluate the usefulness of sonography as an initial study in patients with suspected ureteral stone. We have undertaken a prospective study for 106 patients with suspected ureteral stone during 15 months. All the patients subsequently underwent urography at a mean interval of 1.8 days after the abdominopelvic sonography. We had only a clinical impression at the sonography and didn't refer to the other study such as KUB. We observed the degree of hydronephrosis using a grading system by Ellenbogen et aland location and size of stone. Seventy four patients had ureteral stone disease. The sonographic findings of these 74 patients showed a stone with hydronephrosis in 61 patients, a stone without hydronephrosis in 9, only hydronephrosis without stone in 2, and unremarkable finding in 2. In 3 of the remaining 32 patients, sonography showed hydronephrosis without stone. Locations of stone were 9 patients of ureteropelvic junction(UPJ), 19 of proximal ureter, 30 of distal ureter, and 16 of ureterovesical junction(UVJ). The sensitivity of sonography for stone was 95% and the specificity was 100%. When a ureteral stone was present, ipsilateral hydronephrosis was detected in 85% of cases on sonography. When only hydronephrosis without stone was detected on sonography, a ureteral stone was diagnosed in 2(40%) of 5 patients. Mean discrepancy of stone size between sonography and KUB was 3.1mm and stone size on sonography was larger. Grade of hydronephrosis between sonography and urography was the same in 32(59%) of 54 patients, whose stones were not expelled until urography after sonography. Sonography could be used as an initial study in patients with suspected ureteral stone.

  13. Effect of Micro-Structure on Fatigue Behavior of Intact Rocks under Completely Reversed Loading

    Directory of Open Access Journals (Sweden)

    Saeed Jamali Zavareh

    2017-01-01

    Full Text Available Rock formations and structures can be subjected to both static and dynamic loadings. Static loadings resulting from different sources such as gravity and tectonic forces and dynamic forces are intermittently transmitted via vibrations of the earth’s crust, through major earthquakes, rock bursts, rock blasting and drilling and also, traffic. Reaction of rocks to cyclic and repetitive stresses resulting from dynamic loads has been generally neglected with the exception of a few rather limited studies. In this study, , two crystalline quarry stones in Iran; (Natanz gabbro and Green onyx and one non-crystalline rock (Asmari limestone are used to evaluate the effect of micro-structure of intact rock on fatigue behavior. These rocks have different mineral compositions and formation conditions. A new apparatus based on rotating beam fatigue testing machine (R.R.Moore, which is commonly used for laboratory fatigue test in metals, is developed and fatigue behavior and existence of the endurance limit were evaluated for the mentioned rocks based on stress-life method. The obtained results in the variation of applied amplitude stress versus loading cycle number (S-N diagram followed common relationship in other materials. In addition, the endurance limit is perceived for all tested rocks. The results also illustrated that the endurance limits for all types of tested rocks in this study are ranged between 0.4 and 0.6 of their tensile strengths. The endurance limit to tensile strength fraction of green onyx and Natanz gabbro were approximated in a higher value compared to the Asmari limestone with non-crystalline micro-structure.

  14. Surgical versus endoscopic treatment of bile duct stones

    DEFF Research Database (Denmark)

    Martin, D J; Vernon, D R; Toouli, J

    2006-01-01

    10% to 18% of patients undergoing cholecystectomy for gallstones have common bile duct (CBD) stones. Treatment options for these stones include pre- or post-operative endoscopic retrograde cholangiopancreatography (ERCP) or open or laparoscopic surgery.......10% to 18% of patients undergoing cholecystectomy for gallstones have common bile duct (CBD) stones. Treatment options for these stones include pre- or post-operative endoscopic retrograde cholangiopancreatography (ERCP) or open or laparoscopic surgery....

  15. The challenge of cystine and struvite stone formers: clinical, metabolic and surgical assessment

    Science.gov (United States)

    Yamaçake, Kleiton G. R.; Marchini, Giovanni S.; Reis, Sabrina; Danilovic, Alexandre; Vicentini, Fábio C.; Torricelli, Fábio C. M.; Srougi, Miguel; Mazzucchi, Eduardo

    2016-01-01

    ABSTRACT Purpose: To compare the clinical, metabolic, and calculi characteristics of cystine and struvite stone patients after percutaneous nephrolithotripsy (PCNL). Material and Methods: Between January/2006-July/2013, 11 cystine stone patients were treated in our clinic. Of those, 3 were excluded due to incomplete follow-up. Eight cystine stone patients (2 with bilateral disease; 10 renal units-RU) were considered for further analysis. A cohort of 8 struvite stone formers (10RU) was matched having the same age, gender, body mass index (BMI) and Guys stone score. Analyzed parameters comprised demographic data, serum/urinary metabolic evaluation and surgical outcomes. Results: Both groups had 6 female patients. Groups were similar in regards to age, gender, BMI, stone burden, and serum creatinine (p=NS). All patients had PCNL as the first surgical treatment modality. Stone free rate (SFR) after the first PCNL tended to be lower (0%) in the cystine compared to the struvite group (40%)(p=0.08). Final SFR after secondary procedures increased to 70% in cystine and 80% in struvite patients (p=1.0); mean number of procedures to achieve stone free status was higher in the first group (3.57 vs. 2.0;p=0.028). Hypocitraturia was found in all patients, but struvite cases presented with lower mean urinary citrate levels (p=0.016). Other common abnormalities were elevated urinary pH (cystine 75% and struvite 62.5%;p=1.0) and low urinary volume (62.5%,37.5%;p=0.63). Conclusion: Multiple interventions and suboptimal stone free rates are trait of the significant stone burden of struvite and cystine patients. Underlying metabolic abnormalities characterized by increased urinary pH, hypocitraturia and low urinary volume are often encountered in both populations. PMID:27622279

  16. The importance of stress percolation patterns in rocks and other polycrystalline materials.

    Science.gov (United States)

    Burnley, P C

    2013-01-01

    A new framework for thinking about the deformation behavior of rocks and other heterogeneous polycrystalline materials is proposed, based on understanding the patterns of stress transmission through these materials. Here, using finite element models, I show that stress percolates through polycrystalline materials that have heterogeneous elastic and plastic properties of the same order as those found in rocks. The pattern of stress percolation is related to the degree of heterogeneity in and statistical distribution of the elastic and plastic properties of the constituent grains in the aggregate. The development of these stress patterns leads directly to shear localization, and their existence provides insight into the formation of rhythmic features such as compositional banding and foliation in rocks that are reacting or dissolving while being deformed. In addition, this framework provides a foundation for understanding and predicting the macroscopic rheology of polycrystalline materials based on single-crystal elastic and plastic mechanical properties.

  17. UV Ink-Jet printability and durability of stone and foil

    Directory of Open Access Journals (Sweden)

    Tadeja Muck

    2014-07-01

    Full Text Available he use of ultraviolet (UV printing technology has impacted printing industry in last years due to its applicability on many different »absorptive« as well as »non-absorptive« printing materials. The printability of building materials and recycled foils is relatively unknown. For primary building materials like stones, functionality can be explored with the use of UV printing technology; increased visual, informative effect or even “creative printing” of buildings. Also several aspects of recycled foils reusability as a printing material could be find (printed packaging material or also like secondary building materials. In the present study, printability of the stone and recycled foil and durability of UV prints was explored by means of macroscopically and microscopically characterization. Results indicate that higher print quality can be achieved on polished stone and on coated foil, which surfaces have higher smoothness. Durability of UV prints at freezing is higher at unpolished stone and coated foil that is at materials with the higher surface energy.

  18. Safety and efficacy of staged retrograde intrarenal surgery for large stone burden of renal stones in selected patients: A single-center experience

    Directory of Open Access Journals (Sweden)

    Cheng-Feng Lin

    2017-06-01

    Conclusion: To the best of our knowledge, RIRS for large renal stone manipulation is an effective and safe treatment modality currently. In our study, the single RIRS SFR was superior to PNL or SWL even when the stone burden was between 2.0 cm and 3.0 cm (80.2%. For those patients whose stone burden was over 3.0 cm or for those with comorbidities, staged RIRS resulted in a lower complication rate, reduced hospital stay, and better SFR (76.5%.

  19. Effect of Ferrous Additives on Magnesia Stone Hydration

    Science.gov (United States)

    Zimich, V.

    2017-11-01

    The article deals with the modification of the magnesia binder with additives containing two- and three-valent iron cations which could be embedded in the chloromagnesium stone structure and also increase the strength from 60 MPa in a non-additive stone to 80MPa, water resistance from 0.58 for clear stone to 0.8 and reduce the hygroscopicity from 8% in the non-additive stone to 2% in the modified chloromagnesium stone. It is proposed to use the iron hydroxide sol as an additive in the quantities of up to 1% of the weight of the binder. The studies were carried out using the modern analysis methods: the differentialthermal and X-ray phase analysis. The structure was studied with an electron microscope with an X-ray microanalyzer. A two-factor plan-experiment was designed which allowed constructing mathematical models characterizing the influence of variable factors, such as the density of the zatcher and the amount of sol in the binder, on the basic properties of the magnesian stone. The result of the research was the magnesia stone with the claimed properties and formed from minerals characteristic for magnesian materials as well as additionally formed from amachenite and goethite. It has been established that a highly active iron hydroxide sol the ion sizes of which are commensurate with magnesium ions is actively incorporated into the structure of pentahydroxychloride and magnesium hydroxide changing the habit of crystals compacting the structure of the stone and changing its hygroscopicity.

  20. Pancreatic Stones: Treat or Ignore?

    Directory of Open Access Journals (Sweden)

    DA Howell

    1999-01-01

    Full Text Available Painful, chronic pancreatitis is of complex etiology, but increasing clinical experience suggests that removal of pancreatic duct stones in many cases significantly improves patients’ symptoms. The development and refinement of therapeutic endoscopic retrograde choledochopancreatography have permitted improved access to the pancreatic duct, which makes the development of new techniques of stone fragmentation and fragment removal a much more successful nonsurgical intervention. A major step forward has been the understanding of the safety and efficacy of pancreatic sphincterotomy, which is necessary for the removal of these difficult stones. The recognition that extracorporeal shock wave lithotripsy can be delivered safely with good efficacy has revolutionized the nonsurgical management of pancreatic duct stones. Nevertheless, advanced and sophisticated therapeutic endoscopy is necessary to achieve clearance of the duct, which can generally be accomplished in the majority of selected patients. State-of-the-art treatments are described, and some new approaches using pancreatoscopy and electrohydrolic lithotripsy are discussed. Newly recognized long term complications are reviewed. Finally, it must be recognized that chronic pancreatitis is an ongoing disease that does not have a simple treatment or cure, and frequently represents a process of remissions and relapses requiring interventions and problem solving.

  1. Stone clearance after extracorporeal shockwave lithotripsy in patients with solitary pure calcium oxalate stones smaller than 1.0 cm in the proximal ureter, with special reference to monohydrate and dihydrate content.

    Science.gov (United States)

    Ichiyanagi, Osamu; Nagaoka, Akira; Izumi, Takuji; Kawamura, Yuko; Tsukigi, Masaaki; Ishii, Tatsuya; Ohji, Hiroshi; Kato, Tomoyuki; Tomita, Yoshihiko

    2013-04-01

    The aim of this study was to assess stone-free rates following extracorporeal shockwave lithotripsy (ESWL) of pure calcium oxalate (CaOx) stones in the proximal ureter. The investigators retrospectively examined 53 patients with 5-10 mm pure CaOx stones in the proximal ureter from the medical archives of 593 consecutive patients treated with ESWL. The compositions of calcium oxalate monohydrate (COM) and dihydrate (COD) in a given stone were determined by infrared spectrometry. Stone size, attenuation number and stone-to-skin distance (SSD) were measured using plain radiography and computed tomography (CT). ESWL success was evaluated by stone-free status after the first single session. On average, calculi were 8.0 × 5.3 mm in size, with an SSD of 11.0 cm. The mean CT attenuation value was 740.1 HU. Attenuation numbers correlated significantly with stone diameter (r = 0.49), but had no correlation with the stone content of COM or COD. A negative correlation was observed between COM and COD content (r = -0.925). With regard to patients' physical characteristics and COM and COD content, no differences were found between study subgroups with stone-free and residual status (n = 38 and 15, respectively). There were also no differences in clinical features between patient subgroups with COM- or COD-predominant stones (n = 22 and 31, respectively). The findings indicated that the differences in COM and COD content of CaOx stones had no impact on stone clearance after ESWL and that a favorable stone-free rate of the stones treated with ESWL may be achieved independently of CaOx hydration.

  2. Percutaneous treatment of extrahepatic bile duct stones assisted by balloon sphincteroplasty and occlusion balloon

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yong Sung; Kim, Ji Hyung; Choi, Young Woo; Lee, Tae Hee; Hwang, Cheol Mog; Cho, Young Jun; Kim, Keum Won [Konyang University Hospital, Daejeon (Korea, Republic of)

    2005-12-15

    To describe the technical feasibility and usefulness of extrahepatic biliary stone removal by balloon sphincteroplasty and occlusion balloon pushing. Fifteen patients with extrahepatic bile duct stones were included in this study. Endoscopic stone removal was not successful in 13 patients, and two patients refused the procedure due to endoscopy phobia. At first, all patients underwent percutaneous transhepatic biliary drainage (PTBD). A few days later, through the PTBD route, balloon assisted dilatation for common bile duct (CBD) sphincter was performed, and then the stones were pushed into the duodenum using an 11.5 mm occlusion balloon. Success rate, reason for failure, and complications associated with the procedure were evaluated. Eight patients had one stone, five patients had two stones, and two patients had more than five stones. The procedure was successful in 13 patients (13/15). In 12 of the patients, all stones were removed in the first trial. In one patients, residual stones were discovered on follow-up cholangiography, and were subsequently removed in the second trial. Technical failure occurred in two patients. Both of these patients had severely dilated CBD and multiple stones with various sizes. Ten patients complained of pain in the right upper quadrant and epigastrium of the abdomen immediately following the procedure, but there were no significant procedure-related complications such as bleeding or pancreatitis. Percutaneous extrahepatic biliary stone removal by balloon sphincteroplasty and subsequent stone pushing with occlusion balloon is an effective, safe, and technically feasible procedure which can be used as an alternative method in patients when endoscopic extrahepatic biliary stone removal was not successful.

  3. Percutaneous treatment of extrahepatic bile duct stones assisted by balloon sphincteroplasty and occlusion balloon

    International Nuclear Information System (INIS)

    Park, Yong Sung; Kim, Ji Hyung; Choi, Young Woo; Lee, Tae Hee; Hwang, Cheol Mog; Cho, Young Jun; Kim, Keum Won

    2005-01-01

    To describe the technical feasibility and usefulness of extrahepatic biliary stone removal by balloon sphincteroplasty and occlusion balloon pushing. Fifteen patients with extrahepatic bile duct stones were included in this study. Endoscopic stone removal was not successful in 13 patients, and two patients refused the procedure due to endoscopy phobia. At first, all patients underwent percutaneous transhepatic biliary drainage (PTBD). A few days later, through the PTBD route, balloon assisted dilatation for common bile duct (CBD) sphincter was performed, and then the stones were pushed into the duodenum using an 11.5 mm occlusion balloon. Success rate, reason for failure, and complications associated with the procedure were evaluated. Eight patients had one stone, five patients had two stones, and two patients had more than five stones. The procedure was successful in 13 patients (13/15). In 12 of the patients, all stones were removed in the first trial. In one patients, residual stones were discovered on follow-up cholangiography, and were subsequently removed in the second trial. Technical failure occurred in two patients. Both of these patients had severely dilated CBD and multiple stones with various sizes. Ten patients complained of pain in the right upper quadrant and epigastrium of the abdomen immediately following the procedure, but there were no significant procedure-related complications such as bleeding or pancreatitis. Percutaneous extrahepatic biliary stone removal by balloon sphincteroplasty and subsequent stone pushing with occlusion balloon is an effective, safe, and technically feasible procedure which can be used as an alternative method in patients when endoscopic extrahepatic biliary stone removal was not successful

  4. Granites of Salamanca. A perfect example for the recognition of natural stone as a heritage resource and their use in restoration

    International Nuclear Information System (INIS)

    González, C.; Pereira, D.; Baltuille, J.M.

    2017-01-01

    In the province of Salamanca (Spain) there are several quarries that used to be the source of natural stone used in the construction of historic buildings and that are today recognized by UNESCO as World Heritage Sites. In this study we investigated the granites used in the construction and restoration of the lower ashlars of the walls of different buildings in Salamanca, Alba de Tormes, Ciudad Rodrigo and Ledesma. The characterization of the different types of granite and their current state of preservation may serve to adopt specific measures for their possible use in the restoration of the architectural heritage of the province, if this should become necessary. Despite the variety of materials observed in the lower parts of the buildings (ranging from sandstone to conglomerate to granite), the stone most frequently used was the granite from Los Santos and the Martinamor granite, followed by the vaugneritic granites from Ledesma. In general the granite materials are in a good state of conservation but the existence of certain pathologies that have given rise to processes of flaking and discoloration of the rock suggests that it will be necessary to make a consistent assessment when deciding about possible actions aimed at replacing materials in these historic buildings Moreover, the various granites differ from one another and pieces should not be replaced without perfect identification of the specific type to which they belong. A detailed study of these granites is crucial for the nomination of some of them as candidates for the denomination Global Heritage Stone Resource and the whole set of Salamanca province lithologies as a Global Heritage Stone Province. [es

  5. Strength Improvement of Clay Soil by Using Stone Powder

    Directory of Open Access Journals (Sweden)

    Ahmed Sameer Abdulrasool

    2015-05-01

    Full Text Available Soil stabilization with stone powder is a good solution for the construction of subgrade for road way and railway lines, especially under the platforms and mostly in transition zones between embankments and rigid structures, where the mechanical properties of supporting soils are very influential. Stone powder often has a unique composition which justifies the need for research to study the feasibility of using this stone powder type for ground improvement applications. This paper presents results from a comprehensive laboratory study carried out to investigate the feasibility of using stone powder for improvement of engineering properties of clays. The stone powder contains bassanite (CaSO4. ½ H2O, and Calcite (CaCO3. Three percentages are used for stone powder (1%, 3% and 5% by dry weight of clay. Several tests are made to investigate the soil behavior after adding the stone powder (Atterberg limits, Standard Proctor density, Grain size distribution, Specific gravity, Unconfined Compressive test, and California bearing ratio test. Unconfined Compressive tests conducted at different curing. The samples are tested under both soaked and unsoaked condition. Chemical tests and X-ray diffraction analyses are also carried out. Stone powder reacts with clay producing decreasing in plasticity and The curves of grain size distribution are shifted to the coarse side as the stone powder percentage increase; the soil becomes more granular, and also with higher strength.

  6. Contemporary Management of Struvite Stones Using Combined Endourologic and Medical Treatment: Predictors of Unfavorable Clinical Outcome.

    Science.gov (United States)

    Iqbal, Muhammad Waqas; Youssef, Ramy F; Neisius, Andreas; Kuntz, Nicholas; Hanna, Jonathan; Ferrandino, Michael N; Preminger, Glenn M; Lipkin, Michael E

    2016-07-01

    Struvite stones have been associated with significant morbidity and mortality, yet there has not been a report on the medical management of struvite stones in almost 20 years. We report on the contemporary outcomes of the surgical and medical management of struvite stones in a contemporary series. A retrospective review of patients who were treated with percutaneous nephrolithotomy (PCNL) for struvite stones at Duke University Medical Center between January 2005 and September 2012 identified a total of 75 patients. Of these, 43 patients had adequate follow-up and were included in this analysis. Stone activity, defined as either stone recurrence or stone-related events, and predictors of activity were evaluated after combined surgical and medical treatment. The study included 43 patients with either pure (35%) or mixed (65%) struvite stones with a median age of 55±15 years (range 21-89 years). The stone-free rate after PCNL was 42%. Stone recurrence occurred in 23% of patients. Postoperatively, 30% of patients had a stone-related event, while 60% of residual stones remained stable with no growth after a median follow-up of 22 months (range 6-67 mos). Kidney function remained stable during follow-up. Independent predictors of stone activity included the presence of residual stones >0.4 cm(2), preoperative large stone burden (>10 cm(2)), and the presence of medical comorbidities (P<0.05). Struvite stones can be managed safely with PCNL followed by medical therapy. The majority of patients with residual fragments demonstrated no evidence of stone growth on medical therapy. With careful follow-up and medical management, kidney function can be maintained and stone morbidity can be minimized. Initial large stone burden, residual stones after surgery, and associated medical comorbidities may have deleterious effect on stone recurrence or residual stone-related events.

  7. Bacteriological study and structural composition of staghorn stones removed by the anatrophic nephrolithotomic procedure

    Directory of Open Access Journals (Sweden)

    Hamid Shafi

    2013-01-01

    Full Text Available This study was conducted to determine the composition of staghorn stones and to assess the proportion of infected stones as well as the correlation between infection in the stones and bacteria grown in urine. Samples of 45 consecutive stones removed through anatrophic nephrolithotomic procedures were taken from the operation site and samples of urine were obtained by simultaneous bladder catheterization. The frequency of infection in the stones and correlation between infection of stone and urine samples were determined with respect to the composition of the stones. Twenty-two males and 23 females, with respective mean ages of 48.3 ± 15.6 years and 51 ± 7.4 years, were studied. The stone and urine cultures yielded positive results in ten and 16 patients, respectively, of a total of 45 patients (22.2% and 35.5%, respectively. Calcium oxalate was the main constituent of staghorn stones, seen in 31 patients (68.8%, uric acid in 12 patients (26.6% and struvite and/or calcium phosphate in 11 patients (24.4%. In seven of ten stones with bacterial growth, bacteria were isolated from urine cultures as well, which accounted for a concordance rate of 70%. The bacteria grown in the stone were the cause of urinary tract infection (UTI in 43.5% of the cases. Stone infection was significantly associated with UTI (OR = 6.47; 95% CI 1.43-31.7, P = 0.021 and presence of phosphate in the stones (OR = 18, 95% CI 3.28-99.6, P = 0.0006. E. coli was the most common bacteria grown from the stones, and was isolated in 50% of the cases; Ureaplasma urealyticum was the most common organism causing UTI, grown in 62.5% of the urine samples. There was a high concordance rate between bacteria in the stones and urine. These findings indicate that the urine culture can provide information for selection of an appropriate anti-microbial agent for stone sterilization. In addition, preventing re-growth or recurrence of stones and treatment of post-surgical infections would be

  8. Measuring stone volume - three-dimensional software reconstruction or an ellipsoid algebra formula?

    Science.gov (United States)

    Finch, William; Johnston, Richard; Shaida, Nadeem; Winterbottom, Andrew; Wiseman, Oliver

    2014-04-01

    To determine the optimal method for assessing stone volume, and thus stone burden, by comparing the accuracy of scalene, oblate, and prolate ellipsoid volume equations with three-dimensional (3D)-reconstructed stone volume. Kidney stone volume may be helpful in predicting treatment outcome for renal stones. While the precise measurement of stone volume by 3D reconstruction can be accomplished using modern computer tomography (CT) scanning software, this technique is not available in all hospitals or with routine acute colic scanning protocols. Therefore, maximum diameters as measured by either X-ray or CT are used in the calculation of stone volume based on a scalene ellipsoid formula, as recommended by the European Association of Urology. In all, 100 stones with both X-ray and CT (1-2-mm slices) were reviewed. Complete and partial staghorn stones were excluded. Stone volume was calculated using software designed to measure tissue density of a certain range within a specified region of interest. Correlation coefficients among all measured outcomes were compared. Stone volumes were analysed to determine the average 'shape' of the stones. The maximum stone diameter on X-ray was 3-25 mm and on CT was 3-36 mm, with a reasonable correlation (r = 0.77). Smaller stones (15 mm towards scalene ellipsoids. There was no difference in stone shape by location within the kidney. As the average shape of renal stones changes with diameter, no single equation for estimating stone volume can be recommended. As the maximum diameter increases, calculated stone volume becomes less accurate, suggesting that larger stones have more asymmetric shapes. We recommend that research looking at stone clearance rates should use 3D-reconstructed stone volumes when available, followed by prolate, oblate, or scalene ellipsoid formulas depending on the maximum stone diameter. © 2013 The Authors. BJU International © 2013 BJU International.

  9. Prevalence of renal uric acid stones in the adult.

    Science.gov (United States)

    Trinchieri, Alberto; Montanari, Emanuele

    2017-12-01

    The aim of this study was to estimate uric acid renal stone prevalence rates of adults in different countries of the world. PubMed was searched for papers dealing with "urinary calculi and prevalence or composition" for the period from January 1996 to June 2016. Alternative searches were made to collect further information on specific topics. The prevalence rate of uric acid stones was computed by the general renal stone prevalence rate and the frequency of uric acid stones in each country. After the initial search, 2180 papers were extracted. Out of them, 79 papers were selected after the reading of the titles and of the abstracts. For ten countries, papers relating to both the renal stone prevalence in the general population and the frequency of uric stones were available. Additional search produced 13 papers that completed information on 11 more countries in 5 continents. Estimated prevalence rate of uric acid stones was >0.75% in Thailand, Pakistan, Saudi Arabia, Iran, South Africa (white population), United States and Australia; ranged 0.50-0.75% in Turkey, Israel, Italy, India (Southern), Spain, Taiwan, Germany, Brazil; and uric acid stone formation. A hot and dry climate increases fluid losses reducing urinary volume and urinary pH. A diet rich in meat protein causes low urinary pH and increased uric acid excretion. On the other hand, uric acid stone formation is frequently associated with obesity, metabolic syndrome and diabetes type 2 that are linked to dietary energy excess mainly from carbohydrate and saturated fat and also present with low urine pH values. An epidemic of uric acid stone formation could be if current nutritional trends will be maintained both in developed countries and in developing countries and the areas of greater climatic risk for the formation of uric acid stones will enlarge as result of the "global warming".

  10. Dynamic Mechanical Behavior of Dry and Water Saturated Igneous Rock with Acoustic Emission Monitoring

    Directory of Open Access Journals (Sweden)

    Jun Guo

    2018-01-01

    Full Text Available The uniaxial cyclic loading tests have been conducted to study the mechanical behavior of dry and water saturated igneous rock with acoustic emission (AE monitoring. The igneous rock samples are dried, naturally immersed, and boiled to get specimens with different water contents for the testing. The mineral compositions and the microstructures of the dry and water saturated igneous rock are also presented. The dry specimens present higher strength, fewer strains, and rapid increase of AE count subjected to the cyclic loading, which reflects the hard and brittle behavior and strong burst proneness of igneous rock. The water saturated specimens have lower peak strength, more accumulated strains, and increase of AE count during the cyclic loading. The damage of the igneous rocks with different water contents has been identified by the Felicity Ratio Analysis. The cyclic loading and unloading increase the dislocation between the mineral aggregates and the water-rock interactions further break the adhesion of the clay minerals, which jointly promote the inner damage of the igneous rock. The results suggest that the groundwater can reduce the burst proneness of the igneous rock but increase the potential support failure of the surrounding rock in igneous invading area. In addition, the results inspire the fact that the water injection method is feasible for softening the igneous rock and for preventing the dynamic disasters within the roadways and working faces located in the igneous intrusion area.

  11. MicroCT vs. Hg porosimetry: microporosity in commercial stones

    Science.gov (United States)

    Fusi, N.; Martinez-Martinez, J.; Barberini, V.; Galimberti, L.

    2009-04-01

    Decay of rocks, due both to extrinsic and intrinsic factors, can show up in several different forms, such as neoformation of minerals, decohesion of grains and/or crystals, magnification of previous defects, new discontinuities, etc. Intrinsic factors include the type of material, its properties and microstructure, in particular porosity and microporosity. Extrinsic factors relate to atmosphere and usage of the material itself. Rock degradation has several heavy consequences for commercial stones, such as increase of permeability, loss of material, loss of mechanical strength; these consequences are of crucial importance for conservation of historical buildings. Aim of this study is to compare microporosity of some massive commercial stones by means of X ray microtomography, a non destructive technique, and Hg porosimetry. Nine of the most used Spanish limestones and dolostones have been analysed. The lithotypes have been chosen for their homogeneous mineralogical composition (calcitic or dolomitic) and for their low porosity; some of them have been widely used in Spain for historical buildings. Different lithotypes have been described in thin section: Ambarino (A) and Beige Serpiente (BS): brecciated dolostone, composed by microcrystalline dolomitic clasts, in a dolomitic and/or calcitic microcrystalline matrix. Amarillo Triana (AT): yellow dolomitic marble, with fissures filled up by calcite and Fe oxides. Blanco Alconera (BA): a white-pink homogeneous limestone, with veins. Blanco Tranco (BT): a homogeneous white calcitic marble, without any fissures and/or fractures. Crema Valencia (CV): a pinkish limestone, characterized by abundant stilolythes, filled mainly by quartz (80%) and kaolin (11%). Gris Macael (GM): a calcitic marble wiht darker and lighter beds, conferring a strong anisotropy. Rojo Cehegin (RC): a red fossiliferous limestone with white calcitic veins. Travertino Blanco (TB): a massive white calcitic travertine. Prismatic samples of about 2x1x1 cm

  12. Mineralogical and chemical assessment of concrete damaged by the oxidation of sulfide-bearing aggregates: Importance of thaumasite formation on reaction mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, A. [Centre de Recherche sur les Infrastructures en Beton (CRIB), Universite Laval, 1065 ave de la Medecine, Quebec, QC, Canada G1V 0A6 (Canada); Duchesne, J., E-mail: josee.duchesne@ggl.ulaval.ca [Centre de Recherche sur les Infrastructures en Beton (CRIB), Universite Laval, 1065 ave de la Medecine, Quebec, QC, Canada G1V 0A6 (Canada); Fournier, B. [Centre de Recherche sur les Infrastructures en Beton (CRIB), Universite Laval, 1065 ave de la Medecine, Quebec, QC, Canada G1V 0A6 (Canada); Durand, B. [Institut de recherche d' Hydro-Quebec (IREQ), 1740 boul. Lionel-Boulet, Varennes, QC, Canada J3X 1S1 (Canada); Rivard, P. [Universite de Sherbrooke, Sherbrooke, QC, Canada J1K 2R1 (Canada); Shehata, M. [Ryerson University, 350 Victoria Street, Toronto, ON, Canada M5B 2K3 (Canada)

    2012-10-15

    Damages in concrete containing sulfide-bearing aggregates were recently observed in the Trois-Rivieres area (Quebec, Canada), characterized by rapid deterioration within 3 to 5 years after construction. A petrographic examination of concrete core samples was carried out using a combination of tools including: stereomicroscopic evaluation, polarized light microscopy, scanning electron microscopy, X-ray diffraction and electron microprobe analysis. The aggregate used to produce concrete was an intrusive igneous rock with different metamorphism degrees and various proportions of sulfide minerals. In the rock, sulfide minerals were often surrounded by a thin layer of carbonate minerals (siderite). Secondary reaction products observed in the damaged concrete include 'rust' mineral forms (e.g. ferric oxyhydroxides such as goethite, limonite (FeO (OH) nH{sub 2}O) and ferrihydrite), gypsum, ettringite and thaumasite. In the presence of water and oxygen, pyrrhotite oxidizes to form iron oxyhydroxides and sulphuric acid. The acid then reacts with the phases of the cement paste/aggregate and provokes the formation of sulfate minerals. Understanding both mechanisms, oxidation and internal sulfate attack, is important to be able to duplicate the damaging reaction in laboratory conditions, thus allowing the development of a performance test for evaluating the potential for deleterious expansion in concrete associated with sulfide-bearing aggregates.

  13. Mineralogical and chemical assessment of concrete damaged by the oxidation of sulfide-bearing aggregates: Importance of thaumasite formation on reaction mechanisms

    International Nuclear Information System (INIS)

    Rodrigues, A.; Duchesne, J.; Fournier, B.; Durand, B.; Rivard, P.; Shehata, M.

    2012-01-01

    Damages in concrete containing sulfide-bearing aggregates were recently observed in the Trois-Rivières area (Quebec, Canada), characterized by rapid deterioration within 3 to 5 years after construction. A petrographic examination of concrete core samples was carried out using a combination of tools including: stereomicroscopic evaluation, polarized light microscopy, scanning electron microscopy, X-ray diffraction and electron microprobe analysis. The aggregate used to produce concrete was an intrusive igneous rock with different metamorphism degrees and various proportions of sulfide minerals. In the rock, sulfide minerals were often surrounded by a thin layer of carbonate minerals (siderite). Secondary reaction products observed in the damaged concrete include “rust” mineral forms (e.g. ferric oxyhydroxides such as goethite, limonite (FeO (OH) nH 2 O) and ferrihydrite), gypsum, ettringite and thaumasite. In the presence of water and oxygen, pyrrhotite oxidizes to form iron oxyhydroxides and sulphuric acid. The acid then reacts with the phases of the cement paste/aggregate and provokes the formation of sulfate minerals. Understanding both mechanisms, oxidation and internal sulfate attack, is important to be able to duplicate the damaging reaction in laboratory conditions, thus allowing the development of a performance test for evaluating the potential for deleterious expansion in concrete associated with sulfide-bearing aggregates.

  14. Recurrence rates of urinary calculi according to stone composition and morphology

    DEFF Research Database (Denmark)

    Daudon, Michel; Jungers, Paul; Bazin, Dominique

    2018-01-01

    stone event, with these being more frequent in men (44.4%) than in women (38.9%, p acid (62.5 ± 14.9 years), with the average age of first stones of calcium oxalate falling...... in the middle (40.7 ± 14.6 years for calcium oxalate dihydrate, and 48.4 ± 15.1 years for calcium oxalate monohydrate, COM). By composition alone, COM was among the least recurrent of stones, with only 38.0% of COM stones coming from patients who had had a previous episode; however, when the different...

  15. 'Saurashtra stone anchors' (Ring-stones) from Dwarka and Somnath, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.; Sundaresh; Tripati, S.; Gudigar, P.; Bandodkar, S.N.

    Last two decades of marine archaeological research along the Indian coast has brought to light a large number of stone anchors of different types and sizes, indicating that the Indian coast has witnessed brisk maritime activities in the past...

  16. Percutaneous transhepatic fragmentation of gall stones and extraction of fragments

    International Nuclear Information System (INIS)

    Guenther, R.; Klose, K.; Schmidt, H.D.; Staritz, M.; Mainz Univ.; Mainz Univ.

    1983-01-01

    Attempts at percutaneous removal have been made in 13 patients with solitary and multiple intra- and extra-hepatic biliary duct stones measuring 5 to 30 mm. The stones were fragmented with a Dormia basket and the fragments removed transhepatically. In ten patients the procedure was successful, including one patient with multiple intra-hepatic stones. The procedure can be recommended for cases of calculous obstruction of biliary anastomoses or of stones which could not be removed by endoscopy, or where there is already biliary drainage being carried out, or in patients with a high opertive risk. In two patients, dilatation of the papilla was also carried out, in four patients a stenosis was dilated and in a further two patients, electro-incision of a stenosis was performed. (orig.) [de

  17. DNA FROM ANCIENT STONE TOOLS AND BONES EXCAVATED AT BUGAS-HOLDING, WYOMING

    Science.gov (United States)

    Traces of DNA may preserve on ancient stone tools. We examined 24 chipped stone artifacts recovered from the Bugas-Holding site in northwestern Wyoming for the presence of DNA residues, and we compared DNA preservation in bones and stone tools from the same stratigraphic context...

  18. Study of stone composition changes in melamine-related urinary calculi and its clinical significance.

    Science.gov (United States)

    Li, Yuan; Chen, YiRong; Zhang, Wei; Huang, XiaoGang; Li, WenHui; Ru, XiaoRui; Meng, Min; Xi, Xinsheng; Huang, Gang; Shi, BaoGuang; Liu, Gang; Li, WeiHua; Xu, Hui

    2011-08-01

    To investigate the composition changes in melamine-related urinary calculi and their clinical significance. A total of 49 melamine-related urinary calculi were included from 49 children (age 4-82 months, mean 22). The qualitative analysis of stone composition was determined using Fourier transform infrared. The quantitative analysis of the stone computed tomography (CT) attenuation value, stone uric acid level, and stone calcium level were measured using spiral CT, high-performance liquid chromatography, and flame atomic absorption spectrum, respectively. Fourier transform infrared showed that 41 (84%) of the 49 stones contained uric acid and 25 (51%) contained calcium compounds. The data from the qualitative and quantitative analysis were available for 15 stones because of sample consumption in the detection process (Fourier transform infrared, atomic absorption spectrum, and high-performance liquid chromatography). A negative correlation was observed between stone uric acid level and stone calcium level (n = 15, r = -0.629, P = .009). A positive correlation was observed between the stone calcium level and stone CT attenuation value (n = 25, r = 0.855, P = .000). Compared with the ≤1-year-age group and the 1-2-year-age group, the stone calcium level in the >2-year-age group was significantly greater (27.51% ± 12.65% vs 1.60% ± 1.68% or 10.12% ± 8.69%, P = .000 and P = .003, respectively). Compared with the alkalization-alone group, the stone calcium level in the nonalkalization-alone group was significant greater (19.83% ± 7.48% vs 1.25% ± 1.43%, n = 19, P = .000). The stones from children >2 years old were not amenable to medical treatment because they contained greater levels of calcium, which can be demonstrated by the radiologic "positive stone image" or stone CT attenuation value. We believe that surgical invention will be the best choice for such patients if extracorporeal shock wave lithotripsy has failed. Copyright © 2011 Elsevier Inc. All rights

  19. Tamsulosin and spontaneous passage of ureteral stones in children: a multi-institutional cohort study.

    Science.gov (United States)

    Tasian, Gregory E; Cost, Nicholas G; Granberg, Candace F; Pulido, Jose E; Rivera, Marcelino; Schwen, Zeyad; Schulte, Marion; Fox, Janelle A

    2014-08-01

    Tamsulosin is associated with increased passage of ureteral stones in adults but its effectiveness in children is uncertain. We determined the association between tamsulosin and the spontaneous passage of ureteral stones in children. We performed a multi-institutional retrospective cohort study of patients 18 years or younger who presented between 2007 and 2012 with ureteral stones up to 10 mm and who were treated with tamsulosin or oral analgesics alone. The outcome was spontaneous stone passage, defined as radiographic clearance and/or patient report of passage. Subjects prescribed tamsulosin were matched with subjects prescribed analgesics alone, using nearest neighbor propensity score matching to adjust for treatment selection. Conditional logistic regression models were used to estimate the association between tamsulosin and spontaneous passage of ureteral stones, adjusting for stone size and location. Of 449 children with ureteral stones 334 were eligible for inclusion, and complete data were available for 274 patients from 4 institutions (99 receiving tamsulosin, 175 receiving analgesics alone). Following case matching, there were no differences in age, gender, weight, height, stone size or stone location between the 99 subjects prescribed tamsulosin and the 99 propensity score matched subjects prescribed analgesics alone. In the tamsulosin cohort 55% of ureteral stones passed, compared to 44% in the analgesics alone cohort (p=0.03). In multivariate analysis adjusting for stone size and location tamsulosin was associated with spontaneous passage of ureteral stones (OR 3.31, 95% CI 1.49-7.34). The odds of spontaneous passage of ureteral stones were greater in children prescribed tamsulosin vs analgesics alone. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  20. Preliminary comparison research for origin characteristics of Qingtian stone, Shoushan stone, Changhua chicken-blood stone and Balin stone%青田石、寿山石、昌化鸡血石和巴林石的产地特征初步比较研究

    Institute of Scientific and Technical Information of China (English)

    朱选民

    2011-01-01

    This paper preliminarily researches the origin characteristics of Qingtian stone, Shoushan stone,Changhua chicken-blood stone and Balin stone by means of X-ray powder diffraction and electron paramagnetic resonance and so on, and finds the differences in mineral composition, structure order degree, polymorph characteristics, occurrence state of Fe3+ and mechanism of coloration etc.%文章通过X射线粉晶衍射、电子顺磁共振等方法对青田石、寿山石、昌化鸡血石和巴林石的产地特征进行了初步研究,发现在矿物组成、有序度、多型特征、Fe3+的赋存状态和致色机理等方面存在差异.

  1. Throwing behavior and mass distribution of stone selection in tufted capuchin monkeys (Cebus apella).

    Science.gov (United States)

    Cleveland, A; Rocca, A R; Wendt, E L; Westergaard, G C

    2003-12-01

    Cannell [Journal of Archaeological Science 29:335-339, 2002] argued that sex-based differences among humans in terms of the mass of chosen throwing stones could be used to infer body mass and patterns of sexual dimorphism in early hominids from Olduvai and Koobi Fora by examining the mass distributions of unaltered stone tools at those sites. We examined this hypothesis in tufted capuchin monkeys using a comparative approach, by investigating the relationships among body mass, sex, stone weight preference, and accuracy in a throwing task. The subject sample consisted of nine monkeys trained to perform an aimed-throwing task in which a food reward could be obtained by throwing a stone into a bucket. We found that 1) the subjects showed a strong mean stone mass preference; 2) the females chose heavier stones than the males, in terms of absolute mean selected stone mass and selected stone mass relative to body mass; 3) subjects threw more accurately when they used stones of preferred mass vs. stones of nonpreferred mass; and 4) overall, the males were more accurate in the throwing task than the females. We conclude that capuchins are highly selective when choosing throwing stones, and that this confers an advantage for throwing accuracy. Our results indicate that the sexually dimorphic pattern in stone mass preference observed among humans does not generalize to Cebus apella. We suggest that researchers examining this pattern in humans in an attempt to explain early hominid patterns of dimorphism and behavior should take into account not only stone weight preference, but also its adaptive advantage. Copyright 2003 Wiley-Liss, Inc.

  2. Stability of Reshaping Breakwaters with Special Reference to Stone Durability

    DEFF Research Database (Denmark)

    Frigaard, Peter; Hald, Tue; Burcharth, H. F.

    1996-01-01

    inherently cause some breakage and abrasion of the individual stones and thereby also reduced stability. In order to avoid excessive abrasion a high stone quality is demanded or larger stones must be applied when constructed. To allow the designer to account for abrasion and armour stone breakage due...

  3. Extensive characterizations of bacteria isolated from catheterized urine and stone matrices in patients with nephrolithiasis.

    Science.gov (United States)

    Tavichakorntrakool, Ratree; Prasongwattana, Vitoon; Sungkeeree, Seksit; Saisud, Phitsamai; Sribenjalux, Pipat; Pimratana, Chaowat; Bovornpadungkitti, Sombat; Sriboonlue, Pote; Thongboonkerd, Visith

    2012-11-01

    Urinary tract infections are generally known to be associated with nephrolithiasis, particularly struvite stone, in which the most common microbe found is urea-splitting bacterium, i.e. Proteus mirabilis. However, our observation indicated that it might not be the case of stone formers in Thailand. We therefore extensively characterized microorganisms associated with all types of kidney stones. A total of 100 kidney stone formers (59 males and 41 females) admitted for elective percutaneous nephrolithotomy were recruited and microorganisms isolated from catheterized urine and cortex and nidus of their stones were analyzed. From 100 stone formers recruited, 36 cases had a total of 45 bacterial isolates cultivated from their catheterized urine and/or stone matrices. Among these 36 cases, chemical analysis by Fourier-transformed infrared spectroscopy revealed that 8 had the previously classified 'infection-induced stones', whereas the other 28 cases had the previously classified 'metabolic stones'. Calcium oxalate (in either pure or mixed form) was the most common and found in 64 and 75% of the stone formers with and without bacterial isolates, respectively. Escherichia coli was the most common bacterium (approximately one-third of all bacterial isolates) found in urine and stone matrices (both nidus and periphery). Linear regression analysis showed significant correlation (r = 0.860, P stone matrices. Multidrug resistance was frequently found in these isolated bacteria. Moreover, urea test revealed that only 31% were urea-splitting bacteria, whereas the majority (69%) had negative urea test. Our data indicate that microorganisms are associated with almost all chemical types of kidney stones and urea-splitting bacteria are not the major causative microorganisms found in urine and stone matrices of the stone formers in Thailand. These data may lead to rethinking and a new roadmap for future research regarding the role of microorganisms in kidney stone formation.

  4. Development of lightweight aggregates from stone cutting sludge, plastic wastes and sepiolite rejections for agricultural and environmental purposes.

    Science.gov (United States)

    Moreno-Maroto, José Manuel; González-Corrochano, Beatriz; Alonso-Azcárate, Jacinto; Rodríguez, Luis; Acosta, Anselmo

    2017-09-15

    Three different wastes have been assessed for lightweight aggregate (LWA) manufacturing: granite and marble sludge (COR), sepiolite rejections (SEP) and polyethylene-hexene thermoplastics (P). A preliminary study of the physical and chemical properties of the raw materials was carried out to design proper batches. It was mixed 10% SEP with 90% COR to confer plasticity, and in turn, 0, 2.5, 5 and 10% (w/w) of P was added to check its suitability as a bloating agent. The mixtures were milled, kneaded with water, extruded, shaped into pellets, oven-dried and finally fired at 1100, 1125 and 1150 °C for 4, 8 and 16 min. The main technological properties of the aggregates related to bloating, density, porosity, loss on ignition, water absorption and compressive strength were measured. Scanning Electron Microscopy was used to study the microstructure of some LWAs. 23 out of 29 types of aggregate were lightweight, although neither bloating effect was observed, nor the typical cellular structure comprised of shell and core with relatively large pores was obtained, but a structure consisting of micropores and microchannels. The increase of temperature and time of firing involved a greater sintering, which in turn was translated into higher shrinkage, density and compressive strength values, but less porosity and water absorption. The addition of P did not involve any improvement, indeed it caused a significant decrease in compressive strength. The LWA sintered without P at the minimum time (4 min) and temperature of firing (1100 °C) was selected to assess its water suction capability. The results pointed out that this LWA could be suitable in hydroponics and/or water filtration systems, even better than the commercial LWA Arlita G3. A new and most environment-friendly perspective in LWA industry arises from here, promoting LWA production at relative low temperatures (prior to significant sintering occurs) and using non-plastic silty wastes instead of clays as major

  5. A new look on Imperial Porphyry: a famous ancient dimension stone from the Eastern Desert of Egypt—petrogenesis and cultural relevance

    Science.gov (United States)

    Abu El-Enen, Mahrous M.; Lorenz, Joachim; Ali, Kamal A.; von Seckendorff, Volker; Okrusch, Martin; Schüssler, Ulrich; Brätz, Helene; Schmitt, Ralf-Thomas

    2018-03-01

    Imperial Porphyry, a famous dimension stone of spectacular purple color, was quarried in the Mons Porphyrites area north of Jabal Dokhan in the Eastern Desert of Egypt, from the beginning of the first until the middle of the fifth century AD. During this period, the valuable material was processed as decorative stone and was used for objects of art, reserved exclusively for the Imperial court of the Roman Empire. Later on, only antique spoils of smaller or bigger size have been re-used for these purposes. The Imperial Porphyry is a porphyritic rock of trachyandesitic to dacitic composition that occurs in the uppermost levels of shallow subvolcanic sill-like intrusions, forming a member of the Dokhan Volcanic Suite. Its purple color is mainly due to dispersed flakes of hematite, resulting from hydrothermal alteration of a dark green Common Porphyry of similar composition, underlying the Imperial Porphyry. Both, the Common Porphyry and the purple Imperial Porphyry', are extensively exposed in the Roman quarries. Contacts between Common and Imperial Porphyry are irregular and gradational. In both rock types, intrusive breccias are frequent, indicating a complex intrusion history. U-Th-Pb zircon geochronology on two samples of Imperial Porphyry and one sample of the Common Porphyry yielded an age range of 609-600 Ma, thus confirming earlier results of radiometric dating. Geochemical evidence indicates that both the Imperial and the Common Porphyry are of medium- to high-K calc-alkaline affinity. The magmas have formed by partial melting of a subduction-modified upper mantle. The subsequent intrusion took place within a highly extended terrane (HET).

  6. Fracture mechanics model of stone comminution in ESWL and implications for tissue damage

    Science.gov (United States)

    Lokhandwalla, Murtuza; Sturtevant, Bradford

    2000-07-01

    Focused shock waves administered during extracorporeal shock-wave lithotripsy (ESWL) cause stone fragmentation. The process of stone fragmentation is described in terms of a dynamic fracture process. As is characteristic of all brittle materials, fragmentation requires nucleation, growth and coalescence of flaws, caused by a tensile or shear stress. The mechanisms, operative in the stone, inducing these stresses have been identified as spall and compression-induced tensile microcracks, nucleating at pre-existing flaws. These mechanisms are driven by the lithotripter-generated shock wave and possibly also by cavitation effects in the surrounding fluid. In this paper, the spall mechanism has been analysed, using a cohesive-zone model for the material. The influence of shock wave parameters, and physical properties of stone, on stone comminution is described. The analysis suggests a potential means to exploit the difference between the stone and tissue physical properties, so as to make stone comminution more effective, without increasing tissue damage.

  7. Endoscopic sphincterotomy for common bile duct stones during laparoscopic cholecystectomy is safe and effective

    DEFF Research Database (Denmark)

    Jakobsen, Henrik Loft; Vilmann, Peter; Rosenberg, Jacob

    2011-01-01

    Management strategy for common bile duct (CBD) stones is controversial with several treatment options if stones in the CBD are recognized intraoperatively. The aim of this study was to report our experience with same-session combined endoscopic-laparoscopic treatment of gallbladder and CBD stones....... We retrospectively evaluated 31 patients with cholecystolithiasis and CBD stones undergoing same-session combined endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy and endoscopic stone extraction and laparoscopic cholecystectomy. Same-session ERCP and sphincterotomy were...... performed in all patients, and stone extraction was successfully performed in 29 patients (93%) with 2 failures (7%) due to impacted stones. In 8 patients (26%), the laparoscopic procedure was converted to open cholecystectomy because of dense adhesions or unclear anatomy. Two patients (7%) developed mild...

  8. Impact of stone density on outcomes in percutaneous nephrolithotomy (PCNL)

    DEFF Research Database (Denmark)

    Anastasiadis, Anastasios; Onal, Bulent; Modi, Pranjal

    2013-01-01

    were assigned to a low stone density [LSD, ≤ 1000 Hounsfield units (HU)] or high stone density (HSD, > 1000 HU) group based on the radiological density of the primary renal stone. Preoperative characteristics and outcomes were compared in the two groups. Results. Retreatment for residual stones...... was more frequent in the LSD group. The overall stone-free rate achieved was higher in the HSD group (79.3% vs 74.8%, p = 0.113). By univariate regression analysis, the probability of achieving a stone-free outcome peaked at approximately 1250 HU. Below or above this density resulted in lower treatment...

  9. Comparison of ESWL and ureteroscopic holmium laser lithotripsy in management of ureteral stones.

    Science.gov (United States)

    Cui, Yon; Cao, Wenzhou; Shen, Hua; Xie, Jianjun; Adams, Tamara S; Zhang, Yuanyuan; Shao, Qiang

    2014-01-01

    There are many options for urologists to treat ureteral stones that range from 8 mm to 15 mm, including ESWL and ureteroscopic holmium laser lithotripsy. While both ESWL and ureteroscopy are effective and minimally invasive procedures, there is still controversy over which one is more suitable for ureteral stones. To perform a retrospective study to compare the efficiency, safety and complications using ESWL vs. ureteroscopic holmium laser lithotripsy in management of ureteral stones. Between October 2010 and October 2012, 160 patients who underwent ESWL or ureteroscopic holmium laser lithotripsy at Suzhou municipal hospital for a single radiopaque ureteral stone (the size 8-15 mm) were evaluated. All patients were followed up with ultrasonography for six months. Stone clearance rate, costs and complications were compared. Similarity in stone clearance rate and treatment time between the two procedures; overall procedural time, analgesia requirement and total cost were significantly different. Renal colic and gross hematuria were more frequent with ESWL while voiding symptoms were more frequent with ureteroscopy. Both procedures used for ureteral stones ranging from 8 to 15 mm were safe and minimally invasive. ESWL remains first line therapy for proximal ureteral stones while ureteroscopic holmium laser lithotripsy costs more. To determining which one is preferable depends on not only stone characteristics but also patient acceptance and cost-effectiveness ratio.

  10. Comparison of ESWL and ureteroscopic holmium laser lithotripsy in management of ureteral stones.

    Directory of Open Access Journals (Sweden)

    Yon Cui

    Full Text Available BACKGROUND: There are many options for urologists to treat ureteral stones that range from 8 mm to 15 mm, including ESWL and ureteroscopic holmium laser lithotripsy. While both ESWL and ureteroscopy are effective and minimally invasive procedures, there is still controversy over which one is more suitable for ureteral stones. OBJECTIVE: To perform a retrospective study to compare the efficiency, safety and complications using ESWL vs. ureteroscopic holmium laser lithotripsy in management of ureteral stones. METHODS: Between October 2010 and October 2012, 160 patients who underwent ESWL or ureteroscopic holmium laser lithotripsy at Suzhou municipal hospital for a single radiopaque ureteral stone (the size 8-15 mm were evaluated. All patients were followed up with ultrasonography for six months. Stone clearance rate, costs and complications were compared. RESULTS: Similarity in stone clearance rate and treatment time between the two procedures; overall procedural time, analgesia requirement and total cost were significantly different. Renal colic and gross hematuria were more frequent with ESWL while voiding symptoms were more frequent with ureteroscopy. Both procedures used for ureteral stones ranging from 8 to 15 mm were safe and minimally invasive. CONCLUSION: ESWL remains first line therapy for proximal ureteral stones while ureteroscopic holmium laser lithotripsy costs more. To determining which one is preferable depends on not only stone characteristics but also patient acceptance and cost-effectiveness ratio.

  11. [Usefullness of the StoneBreaker lithotripter for percutaneous nephrolithotomy].

    Science.gov (United States)

    del Peso, Almudena Coloma; González, Inmaculada Fernández; Gálvez, Milagros Jiménez; Abad, Pablo Garrido; Fajardo, Gloria Bocardo; Fernández, Luis Miguel Herranz; Arjona, Manuel Fernández; Torres, Lorenzo Herrero; Sanz, Ignacio Pereira

    2008-01-01

    Throughout the history, many devices have been used for breaking urinary tract stones. StoneBreaker (LMA Urology, Gland, Switzerland) is a second generation of intracorporeal lithotripter, pneumatic and portable, which adds several new advantages, like effectiveness in stone fragmentation and easy handling, very useful during percutaneous lithotripsy. We report the case of a 40 year-old male patient, with a left kidney pyelic lithiasis, who was treated by percutaneous lithotripsy, under general anaesthesia, with StoneBreaker (LMA Urology, Gland, Switzerland) as lithotripter. StoneBreaker (LMA Urology, Gland, Switzerland) is a lithotripter usable with rigid and semirigid ureteroscopes, much more powerful than its predecessors. It is able to decrease the number of shocks necessary for stone fragmentation, without bigger tissue reaction. It also has a more comfortable design due to the absence of connections, and its power by replaceable carbon dioxide cartridges.

  12. Uric acid stones increase the risk of chronic kidney disease.

    Science.gov (United States)

    Li, Ching-Chia; Chien, Tsu-Ming; Wu, Wen-Jeng; Huang, Chun-Nung; Chou, Yii-Her

    2018-02-28

    The aim of this study was to compare the clinical characteristics of uric acid stones and their potential risk for chronic kidney disease (CKD). A total of 401 patients (196 with uric acid stone and 205 without) were enrolled from our database of patients with urolithiasis. We analyzed the clinical demographic features, stone location, urine chemistries, and renal function. There was a significant difference (p uric acid group. Patients with uric acid stones had much lower pH of urine (p uric acid level (p = 0.002). Notably, those with uric acid stones had worse eGFR than those with non-uric acid stones. Multivariate analysis confirmed that age over 60 years (ORs = 9.19; 95% CI 3.5-24.3), female sex (ORs = 4.01; 95% CI 1.8-9.0), hyperuricemia (ORs = 8.47; 95% CI 1.6-43.5), and uric acid stone (OR = 2.86; 95% CI 1.2-6.7) were the independent predictors of poor prognoses in CKD. Therefore, an association exists between uric acid stones and higher prevalence of CKD. Patients with uric acid stones may need close monitoring of renal function during follow-up.

  13. Usefulness of 99mTc-DTPA renography and diuretic renography in predicting successful stone discharge following outpatient ESWL in patients with a single ureteral stone

    International Nuclear Information System (INIS)

    Soga, Norihito; Komeda, Yoshinori; Suzuki, Ryuichi; Kawamura, Juichi.

    1996-01-01

    We analyzed the 99m Tc-DTPA renogram with and without diuresis to predict the possibility of stone discharge on the outpatient basis by renogram patterns. Between October 1993 and December 1995, 99m Tc-DTPA renography was performed in 79 patients with a single ureteral stone. The 99m Tc-DTPA renogram pattern was classified into the three types of normal function, obstruction and lower function patterns and the complete stone discharge rate was 93, 63 and 25%, respectively. In addition, diuretic renography using Furosemide was performed in patients with an obstruction pattern and the three renogram patterns of return to the normal curve, a diuretic response and no response were obtained; the complete stone discharge rate was 44, 65.3 and 93%, respectively. From this study, patients with a single ureteral stone with a normal pattern on the regular DTPA renogram and patients with no response pattern on the diuretic renogram, even if in such patients an obstructive pattern was seen on the regular DTPA renogram, seem to be a good candidate for obtaining a high rate of a stone discharge with extracorporeal shock wave lithotripsy (ESWL) treatment in the outpatients basis. (author)

  14. Laparoendoscopic management of concomitant gallbladder stones and common bile duct stones: what is the best technique?

    Science.gov (United States)

    El-Geidie, Ahmed Abdel-Raouf

    2011-08-01

    The intraoperative use of endoscopic retrograde cholangiopancreatography (ERCP) during laparoscopic cholecystectomy (LC) is a safe, single-stage option for the management of concomitant gallstones (GS) and common bile duct stones (CBDS). This study aims to compare between 2 techniques of combined laparoendoscopic management, which are laparoendoscopic Rendez-vous (LC/LERV) technique and standard ERCP after the completion of LC intraoperative endoscopic sphincterotomy (IOES). Patients with GS and suspected CBDS were included. They were divided into 2 groups; LC/LERV and LC/IOES. Both groups were compared for failure of endoscopic sphincterotomy/stone extraction, operative time, conversion rate, mortality/morbidity, and length of hospital stay. Between October 2007 and February 2010, 98 patients with GS and CBDS were eligible for inclusion in the study. They were prospectively randomized into 2 groups; LC/LERV (N=45) and LC/IOES (N=53). There were no differences in preoperative parameters between both groups. There was a significant difference in operative time (shorter for LC/IOES). No difference was noted in success/failure rate, post-ERCP pancreatitis. Both Standard ERCP after the completion of LC and LC/LERV are valid single-session management for CBD stones, but LC-ERCP may be preferred.

  15. Screening and Management of Asymptomatic Renal Stones in Astronauts

    Science.gov (United States)

    Reyes, David; Locke, James; Sargsyan, Ashot; Garcia, Kathleen

    2017-01-01

    Management guidelines were created to screen and manage asymptomatic renal stones in U.S. astronauts. The true risk for renal stone formation in astronauts due to the space flight environment is unknown. Proper management of this condition is crucial to mitigate health and mission risks. The NASA Flight Medicine Clinic electronic medical record and the Lifetime Surveillance of Astronaut Health databases were reviewed. An extensive review of the literature and current aeromedical standards for the monitoring and management of renal stones was also done. This work was used to develop a screening and management protocol for renal stones in astronauts that is relevant to the spaceflight operational environment. In the proposed guidelines all astronauts receive a yearly screening and post-flight renal ultrasound using a novel ultrasound protocol. The ultrasound protocol uses a combination of factors, including: size, position, shadow, twinkle and dispersion properties to confirm the presence of a renal calcification. For mission-assigned astronauts, any positive ultrasound study is followed by a low-dose renal computed tomography scan and urologic consult. Other specific guidelines were also created. A small asymptomatic renal stone within the renal collecting system may become symptomatic at any time, and therefore affect launch and flight schedules, or cause incapacitation during a mission. Astronauts in need of definitive care can be evacuated from the International Space Station, but for deep space missions evacuation is impossible. The new screening and management algorithm has been implemented and the initial round of screening ultrasounds is under way. Data from these exams will better define the incidence of renal stones in U.S. astronauts, and will be used to inform risk mitigation for both short and long duration spaceflights.

  16. Stone Soup: The Teacher Leader's Contribution

    Science.gov (United States)

    Bambrick-Santoyo, Paul

    2013-01-01

    In the tale of "Stone Soup," a stranger vows to make soup for everyone in a village using only a stone--and convinces everyone in town to throw an ingredient into the stewpot. Schools that need to improve teacher practice quickly can also make stone soup, the author says, by harnessing the power of well-prepared teacher leaders to…

  17. Renal and prostate stones composition in alkaptonuria: a case report.

    Science.gov (United States)

    Wolff, Fleur; Biaou, Ibrahim; Koopmansch, Caroline; Vanden Bossche, Marc; Pozdzik, Agnieszka; Roumeguère, Thierry; Cotton, Frédéric

    2015-12-01

    Alkaptonuria is a genetic disorder characterized by an accumulation of homogentisic acid due to an enzymatic defect of homogentisate 1,2 dioxygenase. The homogentisic acid is excreted exclusively by both glomerular filtration and tubular secretion leading to the renal parenchyma being exposed to high concentrations of homogentisic acid. The alkaptonuric patients are at higher risk of renal stones (and of prostate stones for males), usually in the later stages of the disease. We describe the case of a 51-year-old man whose renal and prostate stones were analyzed by X-ray diffraction and infrared spectroscopy, respectively. We review the cases of alkaptonuria (AKU) patients reported in the literature for whom the composition of kidney or prostate stones was assessed with physical or chemical techniques. In this paper, we also discuss the advantages and drawbacks of the different methodologies.

  18. [The effiectiveness of extracorporeal shock wave lithotripsy in treating proxima ureteral stones].

    Science.gov (United States)

    Kogan, M I; Belousov, I I; Yassine, A M

    2017-10-01

    Extracorporeal shock wave lithotripsy (ESWL) has proven efficacy in the treatment of proximal ureteral stones. The research to date has not been able to establish real time to spontaneous stone clearance after ESWL and the appropriateness and effectiveness of -blockers in stimulating residual stone clearance after ESWL. To conduct a comprehensive assessment of the effectiveness of ESWL in treating proximal ureteral stones and determine the appropriateness of using -blockers to stimulate residual stone clearance. ESWL was performed in 40 patients with X-ray positive proximal ureteral stones. Before ESWL and at 3 months after the treatment all patients underwent multispiral computed tomography. ESWL was considered successful if there was a complete clearance of the stones with no residual fragments on the control MSCT. If a residual ureteral stone was found at 3 months after ESWL, a 2-week course of silodosin was administered. Complete stone clearance was achieved in 37.5% of patients. Silodosin therapy for residual stones resulted in stone clearance in 68.4% of cases. Taken together, ESWL monotherapy and additional 3 months of lithokinetic therapy resulted in stone clearance in 70.0% of patients. The remaining patients underwent contact ureteral lithotripsy. Spontaneous stone passage after ESWL for proximal ureteral stones occurs not in all patients. Most commonly it occurred during the first three weeks after ESWL, and thereafter stone passage was not observed. In half of the patients with residual stones they were asymptomatic. The effectiveness of ESWL as a monotherapy for ureteral stones greater than 15 mm is incomplete. Adding silodosin during the long-term post ESWL period improves the passage of asymptomatic residual stones in 2/3 of patients, which makes its use promising.

  19. Factors affecting lower calyceal stone clearance after Extracorporeal shock wave lithotripsy

    Directory of Open Access Journals (Sweden)

    S. Azab

    2013-03-01

    Conclusions: There is no statistically significant effect of stone size, anatomy of the lower calyx and BMI on stone clearance after ESWL of lower calyceal stones. However, small stone size (≤2 cm, a shorter and wider infundibulum and a larger lower-pole infundibulopelvic angle seem to promote a more rapid and more complete stone clearance.

  20. Approach to Residual Kidney Stone Fragments After Shock Wave Therapy

    Directory of Open Access Journals (Sweden)

    Tumay Ižpekci

    2014-04-01

    Full Text Available For kidney stones up to 2 cm in diameter shock wave therapy (SDT is safely applied and kidney stones smaller than 5mm remaining in the kidney after treatment are regarded as clinically insignificant. Management of this condition is still controversial among clinicians. These stones in the kidney may continue to persist without any clinical symptoms or begin to cause clinical signs. In the event that the clinical symptoms are present, it requires detailed urological examination and treatment. The aim in the surgical treatment of urinary tract stones is completely stone clearance but in stones that are not infected, not causing urinary tract obstruction and without clinical symptoms medical treatment is also beneficial fort he prevention of growth and recurrence. In addition, surgical intervention is also possible for the residual stone fragments which become symptomatic during follow-up.