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

Anti-miss-shot control device for selective stone disintegration in extracorporeal shock wave lithotripsy

Science.gov (United States)

Kuwahara, M.; Ioritani, N.; Kambe, K.; Orikasa, S.; Takayama, K.

1991-06-01

A new device to prevent erroneously focused shock waves to the renal parenchyma during extracorporeal shock wave lithotripsy (ESWL) has been developed; an anti-miss-shot control device (AMCD) and experiments have been conducted to evaluate its effectiveness. For shock wave generation and stone localization, piezoceramic elements (PSE) and ultrasound localization, respectively were used. After stone localization, probing ultrasounds (PU) were emmitted from the PSE towards the focal region and the reflected sound levels (RSL) were monitored by the PSE which also functioned as a microphone. A direct hit by the PU to the stone or a miss was judged from the RSL, i.e. a high RSL indicates a direct hit and a low RSL indicates a miss. Shock waves were generated only when the RSL exceeded the level which indicated a direct hit. The experimental results showed that the injury to the renal parenchyma was decreased by using the AMCD. Clinical application of the AMCD is expected to increase the safety of ESWL.

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

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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

DNA FROM ANCIENT STONE TOOLS AND BONES EXCAVATED AT BUGAS-HOLDING, WYOMING

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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...

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 ...

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 18^th 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...

Preservation and concentration of uranium mineralization in the crust of weathering

International Nuclear Information System (INIS)

Ashikhmin, A.A.; Kuznetsov, S.V.; Shmarovich, E.M.

1983-01-01

Inprecision of the concept on indispensable evacuation of U from ores during formation of the crust of weathering of lateritic or kaolinitic profile due to the existence of oxidative situation in the crusts is established. At hydrothermal uranium deposit in Eocambrian sandy-shaly and Paleozoic volcanogenous-sedimentary rocks a high degree of mineralization preservation in lower and medium horizons of Mesozoic-Cenozoic hydro-micaceous-kaolinitic crust of weathering, characterized by reductive situation, presence of carbonaceous substance, pyrite and siderite, is established. Mineralization attained there black composition and was additionally enriched with uranium. A supposition is made that the case is specific for the development of lateritic and kaolinitic crust formation according to ore-bearing rocks, rich in reducing agents-carbonaceous substances, sulfides and minerals of protoxidic iron. The data obtained should be taken into account during prediction and prospecting activities

Fasting and Urinary Stones

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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.

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

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)

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

loss of mass of 5%. It is a natural stone that easily decays in urban environments, therefore the importance of its proper knowledge and characterization. This natural stone, because of its relevance in the main heritage buildings in the monumental city of Granada can be considered a very important natural stone in Andalusia. Its nomination as Global Heritage Stone Resource will help to preserve the material, both in quarries and in historical buildings. This will guarantee the conservation and availability of material for future restoration works when needed. Its nomination is important as well to avoid the mistakes that can be produced from the equal name that is given to other natural stones quarried these days, not only in Andalusia (e.g. Piedra Dorada or Piedra Franca from Porcuna, in Jaén), but in other parts of Spain as well (e.g. Villamayor sandstone or Piedra Franca, quarried in Salamanca). This is a contribution of the Spanish network CONSTRUROCK.

Use of Local Stone: Successes, Failures and Considerations

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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

Genomic and post-genomic effects of anti-glaucoma drugs preservatives in trabecular meshwork

Energy Technology Data Exchange (ETDEWEB)

Izzotti, Alberto, E-mail: izzotti@unige.it [Mutagenesis Unit, IRCCS AOU San Martino – IST, Genova (Italy); Department of Health Sciences, University of Genoa, Via A. Pastore 1, 16132 Genoa (Italy); La Maestra, Sebastiano; Micale, Rosanna Tindara; Longobardi, Maria Grazia [Department of Health Sciences, University of Genoa, Via A. Pastore 1, 16132 Genoa (Italy); Saccà, Sergio Claudio [Ophthalmology Unit, IRCCS AOU San Martino-IST, Genova (Italy)

2015-02-15

Highlights: • Glaucoma drug preservatives induce DNA damage in trabecular meshwork cells. • Cellular alteration is related with the occurrence of activation of apoptosis through the intrinsic pathway. • Drug preservatives unable to induce cell damage are ineffective in killing bacteria. • Anti glaucoma drugs should be formulated as single-dose usage devoid of genotoxic preservatives. - Abstract: Oxidative stress plays an important role in glaucoma. Some preservatives of anti-glaucoma drugs, commonly used in glaucoma therapy, can prevent or induce oxidative stress in the trabecular meshwork. The aim of this study is to evaluate cellular and molecular damage induced in trabecular meshwork by preservatives contained in anti-glaucoma drugs. Cell viability (MTT test), DNA fragmentation (Comet test), oxidative DNA damage (8-oxo-dG), and gene expression (cDNA microarray) have been evaluated in trabecular meshwork specimens and in human trabecular meshwork cells treated with benzalkonium chloride, polyQuad, purite, and sofzia-like mixture. Moreover, antimicrobial effectiveness and safety of preservative contents in drugs was tested. In ex vivo experiments, benzalkonium chloride and polyQuad induced high level of DNA damage in trabecular meshwork specimens, while the effect of purite and sofzia were more attenuated. The level of DNA fragmentation induced by benzalkonium chloride was 2.4-fold higher in subjects older than 50 years than in younger subjects. Benzalkonium chloride, and polyQuad significantly increased oxidative DNA damage as compared to sham-treated specimens. Gene expression was altered by benzalkonium chloride, polyQuad, and purite but not by sofzia. In in vitro experiments, benzalkonium chloride and polyQuad dramatically decreased trabecular meshwork cell viability, increased DNA fragmentation, and altered gene expression. A lesser effect was also exerted by purite and sofzia. Genes targeted by these alterations included Fas and effector caspase-3

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

Nondestructive evaluation of the preservation state of stone columns in the Hospital Real of Granada

Science.gov (United States)

Moreno de Jong van Coevorden, C.; Cobos Sánchez, C.; Rubio Bretones, A.; Fernández Pantoja, M.; García, Salvador G.; Gómez Martín, R.

2012-12-01

This paper describes the results of the employment of two nondestructive evaluation methods for the diagnostic of the preservation state of stone elements. The first method is based on ultrasonic (US) pulses while the second method uses short electromagnetic pulses. Specifically, these methods were applied to some columns, some of them previously restored. These columns are part of the architectonic heritage of the University of Granada, in particular they are located at the patio de la capilla del Hospital Real of Granada. The objective of this work was the application of systems based on US pulses (in transmission mode) and the ground-penetrating radar systems (electromagnetic tomography) in the diagnosis and detection of possible faults in the interior of columns.

Influence of the Distribution of a Spray Paint on the Efficacy of Anti-Graffiti Coatings on a Highly Porous Natural Stone Material

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Maurizio Masieri

2017-01-01

Full Text Available Graffiti on facades often has a heavy impact in social and economic terms, particularly when historical and artistic artefacts are affected. To limit the damages to the surfaces, preventive plans are implemented and anti-graffiti coatings are used as a protective measure. In this study, the distribution of a spray paint inside a highly porous stone, with and without anti-graffiti protection, was investigated. Two commercial sacrificial anti-graffiti systems were used and an acrylic-based paint was applied as staining agent. Environmental scanning electron microscopy and energy-dispersive X-ray spectroscopy (EDS microanalysis were performed to characterise, from the morphological and chemical point of view, the anti-graffiti coatings and the paint. Maps of the main elements were acquired to locate the different products inside the stone. Chemical removers were used to clean the stained surfaces, then the effectiveness of the cleaning was assessed by visual observations and colour measurements, as well as on the basis of percentage of residual stain. The obtained results highlighted that the anti-graffiti efficacy strongly depended on the characteristics of the applied coating. This latter usually acted as a barrier, but good results were obtained only where the stain did not remain as a separate layer, but penetrated the protective coating. Microcracks in the anti-graffiti coating were able to nullify the protective action.

The influence of water on the strength of Neapolitan Yellow Tuff, the most widely used building stone in Naples (Italy)

Science.gov (United States)

Heap, Michael J.; Farquharson, Jamie I.; Kushnir, Alexandra R. L.; Lavallée, Yan; Baud, Patrick; Gilg, H. Albert; Reuschlé, Thierry

2018-06-01

Neapolitan Yellow Tuff (NYT) has been used in construction in Naples (Italy) since the Greeks founded the city—then called Neapolis—in the sixth century BCE. We investigate here whether this popular building stone is weaker when saturated with water, an issue important for assessments of weathering damage and monument preservation. To this end, we performed 28 uniaxial compressive strength measurements on dry and water-saturated samples cored from a block of the lithified Upper Member of the NYT. Our experiments show that the strength of the zeolite-rich NYT is systematically reduced when saturated with water (the ratio of wet to dry strength is 0.63). Complementary experiments show that two other common Neapolitan building stones—Piperno Tuff and the grey Campanian Ignimbrite (both facies of the Campanian Ignimbrite deposit devoid of zeolites)—do not weaken when wet. From these data, and previously published data for tuffs around the globe, we conclude that the water-weakening in NYT is a consequence of the presence of abundant zeolites (the block tested herein contains 46 wt.% of zeolites). These data may help explain weathering damage in NYT building stones (due to rainfall, rising damp, and proximity to the sea or water table) and the observed link between rainfall and landslides, rock falls, and sinkhole formation in Naples, and the weathering of other buildings built from zeolite-rich tuffs worldwide.

Determining Exposure Factors of Anti-Fogging, Dye, Disinfectant, Repellent, and Preservative Products in Korea.

Science.gov (United States)

Lee, Daeyeop; Kim, Joo-Hyon; Kim, Taksoo; Yoon, Hyojung; Jo, Areum; Lee, Byeongwoo; Lim, Hyunwoo; Kim, Pilje; Seo, Jungkwan

2018-01-30

Reliable exposure factors are essential to determine health risks posed by chemicals in consumer products. We analyzed five risk-concerned product categories (anti-fogging, dye, disinfectant, repellent, and preservative products) for 13 products (three car anti-fogging products, a lens anti-fogging product, two car dye products, two drain disinfectants, an air conditioner disinfectant, a chlorine-based disinfectant, a fabric repellent, an insect repellent for food, and a wood preservative) considered to be of high risk in order to determine exposure factors via web surveys and estimation of amount of product. Among the 3000 participants (1482 (49%) men) aged ≥19 years, drain disinfectants were used most frequently (38.2%); the rate of usage of the other products ranged between 1.1-24.0%. The usage rates for the consumer products differed by sex, age, income, and education. Some consumer products such as car and lens anti-fogging products, chlorine-based disinfectants, fabric repellents, and drain disinfectants were regularly used more than once a month, while car dye products, air conditioner disinfectants, insect repellents for food, and wood preservatives were not regularly used owing to the specific product purposes and seasonal needs. Our results could be used for managing or controlling chemical substances in consumer products and conducting accurate exposure assessments.

Effects of microgravity on renal stone risk assessment

Science.gov (United States)

Pietrzyk, R. A.; Pak, C. Y. C.; Cintron, N. M.; Whitson, P. A.

1992-01-01

Physiologic changes induced during human exposure to the microgravity environment of space may contribute to an increased potential for renal stone formation. Renal stone risk factors obtained 10 days before flight and immediately after return to earth indicated that calcium oxalate and uric acid stone-forming potential was increased after space flights of 4-10 days. These data describe the need for examining renal stone risk during in-flight phases of space missions. Because of limited availability of space and refrigerated storage on spacecraft, effective methods must be developed for collecting urine samples in-flight and for preserving (or storing) them at temperatures and under conditions commensurate with mission constraints.

Accelerated weathering of limestone for CO2 mitigation opportunities for the stone and cement industries

Science.gov (United States)

Langer, W.H.; Juan, C.A.S.; Rau, G.H.; Caldeira, K.

2009-01-01

Large amounts of limestone fines coproduced during the processing of crushed limestone may be useful in the sequestration of carbon dioxide (CO 2). Accelerated weathering of limestone (AWL) is proposed as a low-tech method to capture and sequester CO2 from fossil fuel-fired power plants and other point-sources such as cement manufacturing. AWL reactants are readily available, inexpensive, and environmentally benign. Waste CO 2 is hydrated with water to produce carbonic acid, which then reacts with and is neutralized by limestone fines, thus converting CO2 gas to dissolved calcium bicarbonate. AWL waste products can be disposed of in the ocean. Feasibility requires access to an inexpensive source of limestone and to seawater, thus limiting AWL facilities within about 10 km of the coastline. The majority of U.S. coastal power generating facilities are within economical transport distance of limestone resources. AWL presents opportunities for collaborative efforts among the crushed stone industry, electrical utilities, cement manufactures, and research scientists.

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

Canada, Series, vol. 43. - Global Heritage Stone Resource: An Update. Ed.: Pereira et al. (2015) Episodes, 38-2. - Global Heritage Stone: Towards International Recognition of Building and Ornamental Stones. Ed.: Pereira et al. (2015) Geological Society Special Publications, 407. - Pereira, D. and Baltuille, J.M. (2014) Documenting natural stone to preserve our cultural and architectonic heritage, Materiales de Construccion, 64 (314) - Engineering Geology for Society and Territory - Volume 5. Urban Geology, Sustainable Planning and Landscape Exploitation. Ed.: Lollino, G., et al. (2014). Springer International Publishing Switzerland.

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

Mitigating the Health Risks of Stone Quarrying and Crushing in India ...

International Development Research Centre (IDRC) Digital Library (Canada)

Safety and health in the stone crushing industry : a practical manual for preventing accidents preserving health and keeping a company profitable. Études. Abstract for oral presentation : addressing health risk of communities residing close to stone quarrying and crushing unit using ecohealth framework in Central India.

Wood preservation

Science.gov (United States)

Kevin Archer; Stan Lebow

2006-01-01

Wood preservation can be interpreted to mean protection from fire, chemical degradation, mechanical wear, weathering, as well as biological attack. In this chapter, the term preservation is applied more restrictively to protection from biological hazards.

New quantitative, in-situ characterization of weathering in geomaterials.

Science.gov (United States)

Scrivano, Simona; Gaggero, Laura; Gisbert Aguilar, Josep; Yus Gonzalez, Adrian

2016-04-01

intensity results are defined and categorized. Drdàcky M. & Slìzkovà Z., 2014. In situ peeling tests for assessing the cohesion and consolidation characteristics of historic plasters and render surfaces. Studies in conservation, vol 0. Fitzner B. & Heinrichs K., 2002. Damage diagnosis on stone monuments weathering forms, damage categories and damage indices. - In: Prikryl R. and Viles H.A. (eds.): Understanding and managing stone decay. - Proceedings Internat. Conf. "Stone weathering and atmospheric pollution network (SWAPNET)": 11-56, Charles Univ. Prague (Karolinum Press). ICOMOS.ISCS, 2008 Illustrated glossary on stone deterioration patterns, 78 pp. Scrivano S., Gaggero L. & Taddei A., 2013. Alteration patterns of marble under different environmental exposures: a systematic approach from the Staglieno Monumental cemetery and museum collections in Genoa (Italy). In: Proceedings of the 12th International Congress on Deterioration and Conservation of Stone, New York, 22-26 October 2012. In press.

The erosion of carbonate stone by acid rain: Laboratory and field investigations

International Nuclear Information System (INIS)

Baedecker, P.A.; Reddy, M.M.

1993-01-01

This paper describes a laboratory experiment on the effects of acidic deposition on carbonate stone erosion. It can serve as the basis for an undergraduate (or pre college) experiment in environmental chemistry. Recent field investigations are described that provide measurements of carbonate stone dissolution and mechanical erosion under weathering conditions that are prevalent in the eastern US. The purpose of the laboratory work is to answer questions concerning the effects of hydrogen ion deposition on stone erosion processes that were difficult to resolve on the basis of field experiments alone

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)

The Effect of Methylation and Anti-Oxidant on Discoloration of Weathered Wood Plastic Composites

Directory of Open Access Journals (Sweden)

Peivand Darabi

2011-01-01

Full Text Available As the outdoor application of Wood Plastic Composites (WPCs become more widespread, the resistance of these products against weathering, particularly ultraviolet (UV light becomes more important. When WPCs are exposed to outdoor ultraviolet light, rain, snow and atmosphere pollution, they will be degraded which can be indicated by color fade. To investigate the effects of methylation and Anti-Oxidant separately and together on discoloration of weathered wood plastic composites, composites of poplar wood flour and high density polyethylene.Were made according to the ASTMD 2565, samples were placed in Atlas Xenon apparatus for 250 and 2000 hours. Discoloration and FT-IR spectra of the samples were measured and compared. The results have shown that methylation in short term and long term can relatively reduce the discoloration of weathered samples and also in short term can hinder the photodegradation. FT-IR spectra showed that, in long term, neither of the treatments could protect lignin from irradiation within wood flour. But methylation limited the depth of penetration of weathering. The Antioxidant did not have an influence on color change in a long period of time, but was able to relatively decrease it in short term.

Salt-enhanced chemical weathering of building materials and bacterial mineralization of calcium carbonate as a treatment

Science.gov (United States)

Schiro, M.; Ruiz-Agudo, E.; Jroundi, F.; Gonzalez-Muñoz, M. T.; Rodriguez-Navarro, C.

2012-04-01

Salt weathering is an important mechanism contributing to the degradation and loss of stone building materials. In addition to the physical weathering resulting from crystallization pressure, the presence of salts in solution greatly enhances the chemical weathering potential of pore waters. Flow through experiments quantify the dissolution rates of calcite and quartz grains (63-125 micrometer diameter) when subjected to 1.0 ionic strength solutions of MgSO4, MgCl, Na2SO4 or NaCl. Results indicate that the identity of the cation is the primary control over the dissolution rate of both calcite and quartz substrates, with salt-enhanced dissolution occurring most rapidly in Mg2+ bearing solutions. It has been observed that weathering rates of rocks in nature, as well as building stones, are slowed down by naturally occurring or artificially produced patinas. These tend to be bacterially produced, durable mineralized coatings that lend some degree of protection to the underlying stone surface [1]. Our research shows that bacterially produced carbonate coatings can be quite effective at reducing chemical weathering of stone by soluble salts. The calcite-producing-bacteria used in this study were isolated from stone monuments in Granada, Spain [2] and cultivated in an organic-rich culture medium on a variety of artificial and natural substrates (including limestone, marble, sandstone, quartz, calcite single crystals, glass cover-slips, and sintered porous glass). Scanning electron microscopy (FESEM) was used to image bacterial calcite growth and biofilm formation. In-situ atomic force microscopy (AFM) enabled calculation of dissolution rates of untreated and bacterially treated surfaces. 2D-XRD showed the mineralogy and crystallographic orientation of bacterial calcium carbonate. Results indicate that bacterially produced calcite crystals form a coherent, mechanically resistant surface layer in perfect crystallographic continuity with the calcite substrate (self

A survey of weighted substitution operators and generalizations of Banach-stone theorem

OpenAIRE

R. K. Singh

2005-01-01

The classical Banach-Stone theorem characterizes linear surjective isometries between C(K)-spaces. The main aim of this paper is to present a survey of Banach-Stone-theorem-type results between some function spaces. The weighted substitution operators play an important role in characterization of isometries, disjointness preserving operators, and lattice homomorphisms. Some open problems are given for further investigation.

The use of local natural stone in construction of St. Petersburg region and south-east Finland

Science.gov (United States)

Luodes, Hannu; Härmä, Paavo; Panova, Elena; Pirinen, Heikki; Selonen, Olavi

2013-04-01

construction in the southern Finland and St. Petersburg regions will be documented. That is to generate ideas for definition of new environmental building products using left-over natural stone from quarrying. The project will provide detailed data about long term durability of stone structures in the cities that are along the Baltic Sea shoreline (St. Petersburg, Helsinki) and subject to both mechanical and biological weathering. Mechanical weathering by several annual freeze-thaw cycles is especially typical in these coastal climate conditions. The data will be used in characterization of the durability and weathering mechanisms of different stone types and is used in preparation of guidelines of stone selection for construction and renovation. The data on natural stone resources in the project area will be evaluated and collected in a database. Also the best natural stone evaluation methods from Finland and Russia will be assessed to produce a guidance of best practices for prospecting and evaluation of natural stone occurrences. The project will also generate suggestions for making the natural stone trade between the EU and Russia easier.

MONITORING EROSION OF STONE SURFACES USING TIME-LAPSE AND PTM PHOTOGRAPHY: FIELD STUDY OF A 14TH CENTURY MONASTERY IN YORKSHIRE

Science.gov (United States)

Doehne, E.; Pinchin, S.

2009-12-01

Evaluating stone weathering rates and their relationship to environmental fluctuations is an important challenge in understanding the critical zone and also in efforts to prevent the loss of important cultural heritage in stone, such as monuments, sculpture and archaeological sites. Repeat photography has been widely used to evaluate geological processes such as the retreat of glaciers and the weathering of stone surfaces. However, a fundamental difficulty is that the images are often shot under differing lighting conditions, making the interpretation of stone surface loss particularly challenging. Two developments in photographic documentation show promise for improving the situation. One is the use of digital time-lapse methods to provide more frequent images to correlate stone surface loss with ongoing environmental changes. The other is a relatively new method known as polynomial transform mapping (PTM), which integrates multiple photographs taken at different angles to document more comprehensively the texture of stone surfaces. Using Java-based software, the viewer can control the precise angle of the light source in an interpolated, high-quality image. PTM can produce raking light images from any angle, as well as images with ‘normal’ illumination. We present here results based on several years of macro-photography, time-lapse imaging, and PTM imaging of rapidly eroding stone surfaces at the site of Howden Minster in Yorkshire, UK, which suffers from salt weathering. The images show that surface loss is episodic rather than continuous and in some cases is related to unusual environmental conditions, such as high winds and condensation events. Damage was also found to be synchronous, with surface change (flaking, granular disintegration, and loss of flakes) occurring at the same time in different stone blocks. Crystallization pressure from phase transitions in magnesium sulfate salts appears to be the main cause of the loss of stone surfaces.

[Detection of Clonorchis sinensis eggs in the ground gallbladder stones by microscopy].

Science.gov (United States)

Ma, Rui-Hong; Qiao, Tie; Luo, Xiao-Bing

2012-08-30

Sera, feces, bile and gallbladder stones were collected from 179 patients who accepted gallbladder-preserving cholelithotomy during the period of January to June 2010 at the general surgery department in the Second People's Hospital of Panyu District in Guangzhou. Rapid colloidal gold immunochromatography was used to detect IgG against Clonorchis sinensis. C. sinensis eggs were examined by fecal direct smear, and in bile sediments and ground gallbladder stones. The results showed that the positive rate of rapid colloidal gold immunochromatographic assay for IgG was 51.4%, and the egg positive rate in feces, bile sediments and gallbladder stones was 30.7%, 44.7% and 69.8%, respectively. The detection rate of fecal direct smear was the lowest, while that of the gallbladder stone examination was the highest (P stones.

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

Caoxite-hydroxyapatite composition as consolidating material for the chalk stone from Basarabi-Murfatlar churches ensemble

Science.gov (United States)

Ion, Rodica-Mariana; Turcanu-Caruţiu, Daniela; Fierăscu, Radu-Claudiu; Fierăscu, Irina; Bunghez, Ioana-Raluca; Ion, Mihaela-Lucia; Teodorescu, Sofia; Vasilievici, Gabriel; Rădiţoiu, Valentin

2015-12-01

The development of new composition for surface conservation of some architectural monuments represents now an important research topic. The Basarabi-Murfatlar Ensemble, recognized as the first religious monument from mediaeval Dobrogea (Romania) (from 9th to 11th century), is one of the most impressive archaeological sites of Europe. This ensemble is built from amorphous calcium carbonate, very sensitive to humidity, frost, salts, etc. The aim of this paper is to test on chalk stone samples a new consolidant - hydroxyapatite (HAp) mixed with calcium oxalate trihydrate (caoxite) (COT). Some specific techniques for evaluation its impact on chalk stone surface are used, as follows: petrographical and physical-chemical techniques: SEM, OM, ICP-AES, TGA, FTIR and Raman spectroscopy, chromatic parameters changes, the accelerated weathering tests: heating, freeze-thaw, and their effects on porosity and capillary water uptake by the chalk surface. All these have been evaluated before and after treatment with COT-HAp, putting into evidence the effect of the new composition on the chalk stone surface. HAp induces COT stabilization, and their joint composition can bind weathered stone blocks providing a substantial reinforcement of chalk surface.

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.

Weathering Effect on {sup 99}Tc Leachability from Cementitious Waste Form

Energy Technology Data Exchange (ETDEWEB)

Um, Wooyong [Pohang Univ. of Science and Technology, Pohang (Korea, Republic of)

2012-07-01

The mass transfer of contaminants from the solid phase to the waste form pore water, and subsequently out of the solid waste form, is directly related to the number and size distribution of pores as well as the microstructure of the waste form. Because permeability and porosity are controlled by pore aperture size, pore volume, and pore distribution, it is important to have some indication of how these characteristics change in the waste form during weathering. Knowledge of changes in these key parameters can be used to develop predictive models that estimate diffusivity or permeability of radioactive contaminants can be used to develop predictive models that estimate diffusivity or permeability of radioactive contaminants from waste forms for long-term performance assessment. It is known that dissolution or precipitation of amorphous/crystalline phases within waste forms alters their pore structure and controls the transport of contaminants our of waste forms. One very important precipitate is calcite, which is formed as a result of carbonation reactions in cement and other high-alkalinity waste forms. Enhanced oxidation can also increase Tc leachability from the waste form. To account for these changes, weathering experiments were conducted in advance to increase our understating of the long-term Tc leachability, especially out of the cementitious waste form. Pore structure analysis was characterized using both N{sub 2} absorption analysis and XMT techniques, and the results show that cementitious waste form is a relatively highly-porous material compared to other waste forms studied in this task, Detailed characterization of Cast Stone chunks and monolith specimens indicate that carbonation reactions can change the Cast Stone pore structure, which in turn may correlate with Tc leachability. Short carbonation reaction times for the Cast Stone causes pore volume and surface area increases, while the average pore diameter decreases. Based on the changes in pore

Hölder seminorm preserving linear bijections and isometries

Indian Academy of Sciences (India)

onto lipα(Y ) that preserve the Hölder seminorm. Keywords. Lipschitz function; isometry; linear preserver problem; Banach–Stone theorem. 1. Introduction. The main ... In the context of Lipschitz functions, it seems more natural to raise this type of linear .... being the adjoint map of , is nonempty by the Hahn–Banach theorem.

Sibudu Cave, KwaZulu-Natal: Background to the excavations of middle stone age and iron age occupations

CSIR Research Space (South Africa)

Wadley, L

2004-03-01

Full Text Available . Cultural material from Sibudu includes a huge collection of late MSA stone tools and rare pieces of worked bone, one of which has been directly dated (Cain, this issue). Residue analysis on a large sample of the stone tools shows that the cave occupants... sedimentological analysis4 of six samples shows that the sediments are poorly sorted and immature, largely comprising anthropogenically derived material such as ash, bone and worked stone. A smaller component of the sediments comprises weathered roof...

Microbiological analysis of common preservatives used in food items and demonstration of their in vitro anti-bacterial activity

Directory of Open Access Journals (Sweden)

Tohora Sultana

2014-12-01

Full Text Available Objective: To quantify the microorganisms contaminating the common preservatives used in food as well as to detect their in vitro anti-bacterial traits. Methods: A total of 9 preservatives were subjected to conventional cultural and biochemical methods for microbial enumeration. Anti-bacterial activities were demonstrated through the agar well diffusion method. Results: All samples were found to be contaminated with bacteria up to 105 CFU/g and with the fungal flora within a range of 1 01-1 02 CFU/g. Escherichia coli, Pseudomonas spp. and Staphylococcus spp. were demonstrated in most of the samples. Sodium sulfite and citric acid possessed the strongest anti-bacterial trait against all of the test bacteria. Acetic acid exhibited activity against 6 out of 8 test bacteria while vinegar exhibited the activity against 4 bacteria. Activity of salt was demonstrated only against Listeria spp. and Bacillus spp., while activity of sugar and honey was found only against Escherichia coli and Klebsiella spp., respectively. Conclusions: According to the current investigation, sodium sulfite and citric acid samples were found to be satisfactory preservatives both in terms of microbiological criteria and their antibacterial traits.

Drenov Grič black limestone as a heritage stone from Slovenia

Science.gov (United States)

Kramar, Sabina; Rožič, Boštjan; Žbona, Nina; Bedjanič, Mojca; Mladenović, Ana

2016-04-01

The limestone known as Drenov Grič black limestone is considered one of the most beautiful Slovenian natural stones due to its homogenous black colour interwoven with white veins. Over the centuries it has been exploited from three major quarries west of Ljubljana, with the main quarry at Drenov Grič playing the primary role in supplying building material for the central parts of Slovenia. All the quarries are currently not active. In the area of Drenov grič, one locality of black limestone is protected - Kuclerjev kamnolom quarry. It has the status of 'valuable natural feature of national importance' and is protected as a natural monument. This well-stratified micritic limestone of Triassic (Carnian) age occurs in 10-80 cm thick beds, with thin marl interlayers. The stone contains abundant fossil bivalves and ostracods. Apart from calcite as the main component, dolomite, quartz, illite/muscovite and pyrite are also present. The limestone is relatively rich in carbonaceous and bituminous organic matter, which is responsible for the black colour of the stone. This component does not have any adverse effect on mechanical and physical characteristics. As the lime¬stone is dense, thus facilitating a good polish, it has been commercially considered as marble. The stone has been widely used in Slovenian monuments, not only in Ljubljana but also in other regions of Slovenia. Many inner and outdoor architectural elements were made of this limestone, particularly in the baroque period, which was known for the extensive use of black limestones also in other European countries. The most significant use of this limestone has been recorded in sculptured portals and altars. Some of the important buildings decorated utilising this stone, are the Ljubljana Cathedral, the St. James's Parish Church, and the Franciscan Church of the Annunciation, all of which are located in Ljubljana, some of them having been declared as cultural monuments of local or national importance. When

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.

Bacterial bio-mediated calcite precipitation for monumental stones conservation: methods of evaluation.

Science.gov (United States)

Tiano, P; Biagiotti, L; Mastromei, G

1999-05-01

The weathering of monumental stones is a complex process inserted in the more general 'matter transformation cycle' operated by physical, chemical and biological factors. The consequence of these combined actions is a loss of cohesion with dwindling and scaling of stone material and the induction of a progressive mineral matrix dissolution. In the case of calcareous stones, calcite leaching increases the material porosity and decreases its mechanical features with a general weakening of the superficial structural strength. Attempts to stop, or at least to slow down, deterioration of monumental stones has been made by conservative treatments with both inorganic or organic products. More recent studies show a new approach to hinder these phenomena by inducing a bio-mediated precipitation of calcite directly inside the stone porosity. This can be achieved either through the application of organic matrix macromolecules extracted from sea shells or of living bacteria. The effectiveness of the treatment using calcinogenic bacteria has been evaluated with laboratory tests specifically developed to evaluate the parameters such as : porosity, superficial strength and chromatic changes, influenced by the treatment itself. The results obtained seem to indicate that this type of treatment might not be suitable for monumental stone conservation.

The Value of Original Natural Stone in the Context of Architectural Heritage

Directory of Open Access Journals (Sweden)

Dolores Pereira

2016-02-01

Full Text Available Natural stone is required for maintenance and repair of historically, archaeologically and culturally important structures to prevent deterioration due to weathering and use. Those that have national or World Heritage significance are historically and culturally important. Sometimes, severely damaged buildings may require extensive or complete restoration. The choice of stone should be appropriate in physical and aesthetic terms, ideally from the original source. Researchers, architects, those who specify contracts and other stakeholders need reliable information, but access to, and awareness of, important sources such as manuscripts, publications and collections of samples is often limited. Easier access to information is needed when planning and commissioning works that require the replacement of stone. Making important information more widely available and promoting awareness of the need to maintain adequate supplies of natural stone of suitable quality is a task for both national and international organizations including the Heritage Stone Task Group of IUGS and IAEG. This paper provides some illustrative examples and pointers towards some recent major publications, as well as describing current Heritage Stone Resource and European Union initiatives, all the while requesting further participation from colleagues in this field.

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

Comparison of water absorption methods: testing the water absorption of recently quarried and weathered porous limestone on site and under laboratory conditions

Science.gov (United States)

Rozgonyi-Boissinot, Nikoletta; Agárdi, Tamás; Karolina Cebula, Ágnes; Török, Ákos

2017-04-01

The water absorption of weathering sensitive stones is a critical parameter that influences durability. The current paper compares different methods of water absorption tests by using on site and laboratory tests. The aims of the tests were to assess the water absorption of un-weathered quarry stones and various weathering forms occurring on porous limestone monuments. For the tests a Miocene porous limestone was used that occurs in Central and Western Hungary and especially near and in Budapest. Besides the Hungarian occurrences the same or very similar porous limestones are found in Austria, Slovakia and in the Czech Republic. Several quarries were operating in these countries. Due to the high workability the stone have been intensively used as construction material from the Roman period onward. The most prominent monuments made of this stone were built in Vienna and in Budapest during the 18th -19th century and in the early 20th century. The high porosity and the micro-fabric of the stone make it prone to frost- and salt weathering. Three different limestone types were tested representing coarse-, medium- and fine grained lithologies. The test methods included Rilem tube (Karsten tube) tests and capillary water absorption tests. The latter methodology has been described in detail in EN 1925:2000. The test results of on-site tests of weathered porous limestone clearly show that the water absorption of dissolved limestone surfaces and crumbling or micro-cracked limestone is similar. The water absorption curves have similar inclinations marking high amount of absorbed water. To the contrary, the white weathering crusts covered stone blocks and black crusts have significantly lower water absorptions and many of these crusts are considered as very tight almost impermeable surfaces. Capillary water absorption tests in the laboratory allowed the determination of maximum water absorption of quarried porous limestone. Specimens were placed in 3 mm of water column and the

Measuring change over time: the use of geotagged photographs to evaluate the weathering of monuments

Science.gov (United States)

Doehne, E.

2012-04-01

Evaluating the condition of weathered stone surfaces on a monument, building or sculpture requires information on how those surfaces have evolved. In a number of cases, the documentation related to a site or object is either not readily available or has been lost (due to war, fire, etc.). Exploring the use of geotagged photographs to supplement the evaluation of surface changes to monuments was tested using two sites: the Mausoleum at the Huntington Library, Art Collections, and Botanical Gardens in San Marino, California and the Duomo in Florence, Italy. Increasingly, photographs are being geo-located or geotagged, either automatically via GPS/WiFi or manually. Geolocation tags increase the value of a photograph to researchers by providing the geographic location where the image was taken, often along with the date and time the photograph was acquired. Estimates of the number of geolocated photographs posted to the Internet include 148 million on Flickr.com (as of June 3, 2011) increasing to 172 million as of January 15, 2012. On Panarimo.com five million geolocated images were archived as of October 2007. Tools such as auto-geotag and PhotoOverlay are making it easier for users to locate and exactly position existing photographs and historic photographs on sites such as Google Earth (PhotoOverlays are images that are directly embedded in the Google Earth's landscape). 42 photo sharing websites are listed currently on Wikipedia, with seven having Alexa rankings of less than 200, indicating the popularity of photo sharing and the vast nature of this resource. Preliminary results from the Huntington and the Duomo indicate that geolocated images are indeed a useful tool for aiding in understanding stone weathering patterns and changes over time. However, greater software support and new tools are needed to enable researchers to search, organize and analyze groups of photographs from a single geolocation. Such software would have obvious uses beyond the conservation

Association between gallbladder stones and chronic hepatitis C: Ultrasonographic survey in a hepatitis C and B hyperendemic township in Taiwan

Directory of Open Access Journals (Sweden)

Chia-Yen Dai

2013-08-01

Full Text Available Gallbladder (GB stones have been associated with several metabolic factors and liver diseases. This community-based study aimed at investigating the prevalence rate of GB stones and its associated factors in a hepatitis B virus (HBV/hepatitis C virus (HCV-endemic township in southern Taiwan. A total of 1701 residents (689 males and 1012 females; mean age: 51.2 ± 16.0 years were enrolled in this prospectively designed screening project. Serum biochemistry tests, including testing for levels of serum aspartate aminotransferase, alanine aminotransferase (ALT, hepatitis B surface antigen (HBsAg, and antibody to HCV (anti-HCV were conducted. In addition, a hepatobiliary ultrasonographic (US examination was also conducted. Of the 1701 residents, 243 (14.3% and 475 (27.9% were found to be positive for HBsAg and anti-HCV, respectively. Results of the US examination revealed the prevalence rate of GB stone and fatty liver to be 6.8% and 55.6%, respectively. Using univariate analyses we found that significantly higher proportions of the participants with GB stone were male, over 50 years of age, positive for anti-HCV (p = 0.001, p 50 year were identified as independent factors associated with the formation of GB stones. Anti-HCV was associated with GB stones in males but not in females in both univariate and multivariate analyses. GB stones were found to have a prevalence rate of 6.8% in this HCV/HBV hyperendemic township and are associated with higher mean age. A correlation between chronic hepatitis C and GB stones is observed only among males.

Preservation and restoration of works-of-art via nuclear technology

International Nuclear Information System (INIS)

Coeure, Ph.

1999-01-01

This paper presents the techniques using gamma rays for preservation and restoration of our cultural patrimony. Developed at CEA and by ARC-Nucleart, these techniques, which use mainly Cobalt 60 and Americium 241 sources, allow disinfection and strengthening of the various materials which make up the objects (wood, paper, bone, stone, plaster, etc), together with radiography of wood and stone. (author)

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

Zarzalejo granite (Spain). A nomination for 'Global Heritage Stone Resource'

Science.gov (United States)

Freire Lista, David Martin; Fort, Rafael; José Varas-Muriel, María

2015-04-01

Zarzalejo granite is quarried in the Sierra de Guadarrama (Spanish Central System) foothills, in and around Zarzalejo village, in the province of Madrid, Spain. It is an inequigranular monzogranite medium-to-coarse grained, with a slight porphyritic texture (feldspar phenocrysts) and mafic micro-grained enclaves. In this abstract the candidacy of Zarzalejo granite as a "Global Heritage Resource Stone" (GHSR) is presented. This stone ideally fits the newly proposed designation as it has been used in many heritage buildings and its good petrophysical properties and durability have allowed well preserved constructions such as a Roman road, San Pedro Church in Zarzalejo (1492), Descalzas Reales Monastery in Madrid (1559-1564) and the San Lorenzo del Escorial Royal Monastery (1563-1584), to be declared a World Heritage Site by UNESCO. This level of construction has been a landmark in the extraction and proliferation of historic quarries created due to the high demand that such colossal monuments and buildings with granite, have required for their construction. In the mid-20th century, More, Zarzalejo granite has also been used in restoration works including the Royal Palace and the Reina Sofía Museum (2001-2005), both buildings in Madrid, Spain. Extraction of granite ashlars from tors has been a very frequent activity in the Zarzalejo neighbourhood until mid-twentieth century. So there is also a need to preserve these historic quarries. This type of stone has created a landscape that has been preserved as an open-air museum today where you can see the marks left in the granite due to historic quarry operations. The granite industry has been one of the main pillars of the Zarzalejo regional economy. For centuries, the local community have been engaged in quarrying and have created a cultural landscape based on its building stone. A quarryman monument has been erected in Zarzalejo in honor of this traditional craft as well as an architecture museum at San Lorenzo del

Coatings Preserve Metal, Stone, Tile, and Concrete

Science.gov (United States)

2014-01-01

John B. Schutt, a chemist at Goddard Space Flight Center, created a coating for spacecraft that could resist corrosion and withstand high heat. After retiring from NASA, Schutt used his expertise to create new formulations for Daytona Beach, Florida-based Adsil Corporation, which now manufactures a family of coatings to preserve various surfaces. Adsil has created 150 jobs due to the products.

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...

Weathering of post-impact hydrothermal deposits from the Haughton impact structure: implications for microbial colonization and biosignature preservation.

Science.gov (United States)

Izawa, M R M; Banerjee, Neil R; Osinski, G R; Flemming, R L; Parnell, J; Cockell, C S

2011-01-01

Meteorite impacts are among the very few processes common to all planetary bodies with solid surfaces. Among the effects of impact on water-bearing targets is the formation of post-impact hydrothermal systems and associated mineral deposits. The Haughton impact structure (Devon Island, Nunavut, Canada, 75.2 °N, 89.5 °W) hosts a variety of hydrothermal mineral deposits that preserve assemblages of primary hydrothermal minerals commonly associated with secondary oxidative/hydrous weathering products. Hydrothermal mineral deposits at Haughton include intra-breccia calcite-marcasite vugs, small intra-breccia calcite or quartz vugs, intra-breccia gypsum megacryst vugs, hydrothermal pipe structures and associated surface "gossans," banded Fe-oxyhydroxide deposits, and calcite and quartz veins and coatings in shattered target rocks. Of particular importance are sulfide-rich deposits and their associated assemblage of weathering products. Hydrothermal mineral assemblages were characterized structurally, texturally, and geochemically with X-ray diffraction, micro X-ray diffraction, optical and electron microscopy, and inductively coupled plasma atomic emission spectroscopy. Primary sulfides (marcasite and pyrite) are commonly associated with alteration minerals, including jarosite (K,Na,H(3)O)Fe(3)(SO(4))(2)(OH)(6), rozenite FeSO(4)·4(H(2)O), copiapite (Fe,Mg)Fe(4)(SO(4))(6)(OH)(2)·20(H(2)O), fibroferrite Fe(SO(4))(OH)·5(H(2)O), melanterite FeSO(4)·7(H(2)O), szomolnokite FeSO(4)·H(2)O, goethite α-FeO(OH), lepidocrocite γ-FeO(OH) and ferrihydrite Fe(2)O(3)·0.5(H(2)O). These alteration assemblages are consistent with geochemical conditions that were locally very different from the predominantly circumneutral, carbonate-buffered environment at Haughton. Mineral assemblages associated with primary hydrothermal activity, and the weathering products of such deposits, provide constraints on possible microbial activity in the post-impact environment. The initial period of

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

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.

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

Neutron radiography for the characterization of porous structure in degraded building stones

International Nuclear Information System (INIS)

Barone, G; Mazzoleni, P; Raneri, S; Crupi, V; Longo, F; Majolino, D; Venuti, V; Teixeira, J

2014-01-01

As it is well known, the porous structure of stones can change due to different degradation processes that modify the characteristics of freshly quarried blocks. Their knowledge is fundamental for predicting the behavior of stones and the efficacy of conservative treatments. In this context, neutron radiography is a useful tool not only to visualize the structure of porous materials, but also to evaluate the degree of degradation and surface modifications resulting from weathering processes. Furthermore, since thermal neutrons suffer a strong attenuation by hydrogen, this technique is effective in order to investigate the amount of absorbed water in building materials. In the present work, we report a neutron radiography investigation of limestones cropping out in the South-Eastern Sicily and widely used as building stones in Baroque monuments of the Noto Valley. The analyzed samples have been submitted to cyclic salt crystallization that simulate degradation processes acting in exposed stones of buildings. The obtained results demonstrate the interest of neutron radiography to better understand deterioration processes in limestones and to acquire information useful for restoration projects

Salt damage of stone, plaster and painted layers at a medieval church, South-Hungary

Science.gov (United States)

Török, Ákos; Galambos, Éva

2016-04-01

The Chapel of Pécsvárad is one of the best preserved and oldest medieval stone monument in South Hungary. It dates back to the 11th century. The interior of the chapel is decorated with wall paintings, which are later and probably originating from the late 12th century. The wall painting is partly preserved and it is located on an interior stone wall of the chapel facing to the East. The wall painting shows various forms of damage from salt efflorescence to chipping. The current research provides information on the in situ and laboratory analyses of salts, plasters, pigments and stone material suggesting mechanisms of decay that lead to partial loss of the painting. Both on site techniques and laboratory analyses were performed. Imaging techniques such as UV luminescence and IR thermography were used to identify the moist and salt covered zones on the wall surface. Portable moisture meter were also applied to map the wet zones in the interior and also at the external part of the chapel. Schmidt hammer and Duroscop were used for testing the surface strength of stone. Laboratory tests were focused on mineralogical and chemical compositional analyses. Small samples of stone, mortar, plaster and pigments were tested by optical microscopy, SEM-EDX, XRD and Thermogravimetric analyses. According to our tests the chapel was predominantly made of porous limestone and sandstone. Laboratory analyses proved that the major salt responsible for the damage of external walls are gypsum and halite, while in the interior part higher amount of halite and significant amount of sodium-nitrate were found besides gypsum. The painted layers are on Byzantine-type of plaster with organic compounds (plant fragments) and with a substrate layer rich in calcium carbonate. The identified pigments are dominantly earth pigments such as iron-oxide containing red and yellow (ochre) and green earth. A unique preservation of ultramarine blue in Hungary was found on the wall painting. The partial

Preservation and gamma irradiation

International Nuclear Information System (INIS)

Ramiere, R.

1991-01-01

The paper reviews briefly the application of gamma radiation to preservation of cultural objects for disinsectization, disinfection and strengthening of materials such as wood or stone by impregnation with a liquid resin and in situ polymerization. As heavy equipment is required two facilities are specialized a 1000 T Bq cobalt 60 source at Grenoble (France) and 100 T Bq one at Rostoky (Czechoslovakia). Examples of treated objects are given [fr

Boulders, biology and buildings: Why weathering is vital to geomorphology (Ralph Alger Bagnold Medal Lecture)

Science.gov (United States)

Viles, Heather A.

2015-04-01

Weathering is vital to geomorphology in three main senses. First, it is vital in the sense of being a fundamental and near-ubiquitous earth surface process without which landscapes would not develop, and which also provides a key link between geomorphology and the broader Earth system. Second, weathering is vital in the sense that, as it is heavily influenced by biotic processes, it demonstrates the importance of life to geomorphology and vice versa. In particular, weathering illustrates the many cross-linkages between microbial ecosystems and geomorphology. Finally, it is vital in the sense that weathering provides an important practical application of geomorphological knowledge. Geomorphologists in recent years have contributed much in terms of improving understanding the deterioration of rocks, stone and other materials in heritage sites and the built environment. This knowledge has also had direct implications for heritage conservation. This lecture reviews recent research on each of these three themes and on their linkages, and sets an integrated research agenda for the future. Weathering as a key process underpinning geomorphology and Earth system science has been the subject of much recent conceptual and empirical research. In particular, conceptual research advances have involved improving conceptualisation of scale issues and process synergies, and understanding weathering in terms of non-linear dynamical systems. Empirical advances have included the development of larger datasets on weathering rates, and the application of a wide range of non-destructive and remote sensing techniques to quantify weathering morphologies on boulder and rock surfaces. In recent years, understanding of the complex linkages between ecology and geomorphology (sometimes called biogeomorphology) has advanced particularly strongly in terms of weathering. For example, the influences of disturbance on biota and weathering have been conceptualised and investigated empirically in a

Quantitative impact of the recent abatement of air pollution on the weathering of stone and glass of the UNESCO List in Paris

Science.gov (United States)

Lefèvre, Roger; Ionescu, Anda; Desplat, Julien; Kounkou-Arnaud, Raphaëlle; Perrussel, Olivier; Languille, Baptiste

2016-04-01

Quantitative impact of the recent abatement of air pollution on the weathering of stone and glass of the UNESCO List in Paris R.-A. Lefèvre1, A. Ionescu1, J. Desplat2, R. Kounkou-Arnaud2, O. Perrussel3, B. Languille4 At the beginning of the 21st century air pollution in Paris continued to considerably decrease. An evident visual consequence was the replacement of thick gypseous black crusts by thin grey coverings on the façades. A quantitative approach of this phenomenon was taken by measurement in the field, followed by calculation using Dose-Response Functions (DRF) and mapping the geographic distribution on a grid of 100m x100m of: 1) The total surface of façades of buildings and monuments in the part of Paris inscribed on the UNESCO List between the Ile Saint-Louis and the Concorde Square; 2) The surface of limestone and window glass present on each façade; 3) The distribution of SO2, NO2 and PM10 concentration every year from 1997 to 2014; 4) The response of materials to climatic and pollution doses; 5) The effective damage to limestone and window glass. Results of measurements in the field: 1) The 772 buildings and monuments inventoried have 20 674 m in length and 414 811 m2 in façade surface: they are representative of the centre of Paris; 2) Limestone occupies 348 268 m2 and window glass 207 394 m2; 3) The mean annual concentration in SO2 dropped from 20 to less than 3 μg m-3; NO2 from 60 to 40 μg m-3 and PM10 from 30 to 20 μg m-3. Results by application of DRF: 4) Limestone recession was divided by 5 in 18 years, from 10 to 2 μm y-1, but with only a spatial variation of 2%; 5) Limestone reflectance increased from 70.5 to 72.5 %; 6) The annual mass of deposited and neo-formed particles on window glass decreased from 100 to 20 μg cm-2; 7) The annual haze of window glass decreased from 8 to 3.5%. Effective damage to stone and glass: 8) The mean annual mass of limestone eroded on the façades decreased according to time but with an irregular

A crude protective film on historic stones and its artificial preparation through biomimetic synthesis

Science.gov (United States)

Liu, Qiang; Zhang, Bingjian; Shen, Zhongyue; Lu, Huanming

2006-12-01

A biomimetic film has been found on the surface of the historic stone buildings and monuments. The stone inscriptions under the film are preserved so well that has not been damaged for more than 1000 years. Samples of the crude film have been analyzed by XRD, FTIR, PLM, EDA, SEM and TEM. The results show that it consists mainly of calcium oxalate monohydrate. On the basis of the existence of the organism debris, it is concluded that the film should be a product of biomineralization. According to this hypothesis, a similar film has been prepared on the stone surface through biomimetic synthesis in our laboratory. The preliminary analysis shows that the artificial protective film functions well.

PRESERVATIVE LEACHING FROM WEATHERED CCA-TREATED WOOD

Science.gov (United States)

Disposal of discarded CCA-treated wood in landfills raises concerns with respect to leaching of preservative compounds. When unweathered CCA-treated wood is leached using the toxicity characteristic leaching procedure (TCLP), arsenic concentrations exceed the toxicity characteris...

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

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.

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.

Surface protection treatments of highly porous building stones and sustainability problems

Science.gov (United States)

Calia, Angela; Lettieri, Maria Teresa; Matera, Loredana; Sileo, Maria

2013-04-01

The growing attention to the cultural value and the potential touristic attraction of the historic towns has led to increasing activities of rehabilitation and conservation of the historical built heritage. Chemical treatments have become a common practice for the protection of the stone building surface against the decay agents and traditional methods of protection, such as the application of sacrificial layers, have been even more neglected. The use of chemical products on large scale works on the historical built heritage draws the attention towards the sustainability of the conservation treatments, that involve peculiar features with relation to the different types of stones. Sustainability is undoubtedly in terms of human and environmental impact of the used products, so that the use of new formulations based on aqueous solvent should be preferred. Sustainability also means the equilibrium between the required performances of the treatments and the preservation of the original stone properties (colour, permeability, etc), namely harmlessness and effectiveness of the treatments. This can be a critical aspect when we deal with very porous stones, namely having porosity between 30-40%, that are widely used in many countries as traditional building materials. In most cases no information - or very general recommendations - is reported in the technical sheets of the conservation products with reference to the application to these types of stones. Relevant problems of compatibility can arise from the significant amounts absorbed by the high porous structure, as well as in terms of cost effectiveness of the treatments. In this work several calcarenites with different petro-physic characteristics and porosity between 30 and 45% are concerned for the assessment of the performance of two commercial water based products for stone protection, respectively an alcoxy-siloxane with low molecular weight and a modified organo-silane. This activity is a part of the Apulia

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.

44 CFR 15.5 - Preservation of property.

Science.gov (United States)

2010-10-01

... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Preservation of property. 15.5 Section 15.5 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT... NATIONAL EMERGENCY TRAINING CENTER § 15.5 Preservation of property. At both Mt. Weather and NETC we...

Stone cladding engineering

CERN Document Server

Sousa Camposinhos, Rui de

2014-01-01

This volume presents new methodologies for the design of dimension stone based on the concepts of structural design while preserving the excellence of stonemasonry practice in façade engineering. Straightforward formulae are provided for computing action on cladding, with special emphasis on the effect of seismic forces, including an extensive general methodology applied to non-structural elements. Based on the Load and Resistance Factor Design Format (LRDF), minimum slab thickness formulae are presented that take into consideration stress concentrations analysis based on the Finite Element Method (FEM) for the most commonly used modern anchorage systems. Calculation examples allow designers to solve several anchorage engineering problems in a detailed and objective manner, underlining the key parameters. The design of the anchorage metal parts, either in stainless steel or aluminum, is also presented.

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.

Silsesquioxane-based hybrid nanocomposites with methacrylate units containing titania and/or silver nanoparticles as antibacterial/antifungal coatings for monumental stones

Energy Technology Data Exchange (ETDEWEB)

Aflori, Magdalena [“Petru Poni” Institute of Macromolecular Chemistry, 41A Grigore Ghica Voda Alley, 700487 Iasi (Romania); Simionescu, Bogdana [“Petru Poni” Institute of Macromolecular Chemistry, 41A Grigore Ghica Voda Alley, 700487 Iasi (Romania); “Costin D. Nenitescu” Centre of Organic Chemistry, 202B Splaiul Independentei, 7114 Bucharest (Romania); Bordianu, Irina-Elena; Sacarescu, Liviu; Varganici, Cristian-Dragos; Doroftei, Florica; Nicolescu, Alina [“Petru Poni” Institute of Macromolecular Chemistry, 41A Grigore Ghica Voda Alley, 700487 Iasi (Romania); Olaru, Mihaela, E-mail: olaruma@icmpp.ro [“Petru Poni” Institute of Macromolecular Chemistry, 41A Grigore Ghica Voda Alley, 700487 Iasi (Romania)

2013-11-20

Highlights: • Synthesis of nanocomposites with noble metals having high antibacterial efficiency. • Silver nanoparticles antibacterial activity for monumental stone conservation. • A high antibacterial activity while assuring good stone protection. -- Abstract: The present paper reports on the evaluation of two silsesquioxane-based hybrid nanocomposites with methacrylate units containing titania and/or silver nanoparticles aimed as antibacterial coatings for monumental stones. Sol–gel reaction of titanium isopropoxide and/or 3-(trimethoxysilyl)propyl methacrylate, in the presence of silver nitrate and a primary amine surfactant, yielded new types of hybrid nanocomposites with high antibacterial/antifungal efficacy. Different polymer behaviours regarding a frequently used monumental stone originating from Romania were evidenced through Fourier-transform infrared (FTIR) spectroscopy and powder X-ray diffraction (PXRD) technique. Conclusions regarding the stones acid-resistant character and lower influence of salt weathering on its durability, as well as a better protective coating containing titania units were revealed.

Silsesquioxane-based hybrid nanocomposites with methacrylate units containing titania and/or silver nanoparticles as antibacterial/antifungal coatings for monumental stones

International Nuclear Information System (INIS)

Aflori, Magdalena; Simionescu, Bogdana; Bordianu, Irina-Elena; Sacarescu, Liviu; Varganici, Cristian-Dragos; Doroftei, Florica; Nicolescu, Alina; Olaru, Mihaela

2013-01-01

Highlights: • Synthesis of nanocomposites with noble metals having high antibacterial efficiency. • Silver nanoparticles antibacterial activity for monumental stone conservation. • A high antibacterial activity while assuring good stone protection. -- Abstract: The present paper reports on the evaluation of two silsesquioxane-based hybrid nanocomposites with methacrylate units containing titania and/or silver nanoparticles aimed as antibacterial coatings for monumental stones. Sol–gel reaction of titanium isopropoxide and/or 3-(trimethoxysilyl)propyl methacrylate, in the presence of silver nitrate and a primary amine surfactant, yielded new types of hybrid nanocomposites with high antibacterial/antifungal efficacy. Different polymer behaviours regarding a frequently used monumental stone originating from Romania were evidenced through Fourier-transform infrared (FTIR) spectroscopy and powder X-ray diffraction (PXRD) technique. Conclusions regarding the stones acid-resistant character and lower influence of salt weathering on its durability, as well as a better protective coating containing titania units were revealed

Stone anchors from Bet Dwarka Island, Gujarat, Coast, India: Significance to historical period maritime activities

Digital Repository Service at National Institute of Oceanography (India)

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

Bet Dwarka Island is situated on the extreme west of Indian territory in Jamnagar district of Gujarat. Underwater, the most preserved remains of ancient maritime activity could be the stone anchors of different types, as every boat requires...

Evaluation of hydrophobic treatments applied to stones used in andalusian cathedrals. III.-Accelerated weathering test with polluted atmosphere

Directory of Open Access Journals (Sweden)

Villegas Sánchez, R.

1993-12-01

Full Text Available SUMMARY In this work we study the weathering resistance of samples of five types of stone used in Andalusian Cathedrals, treated with six water repellent products, by subjecting the samples to a SO₂ polluted atmosphere. To evaluate the alteration of the samples, besides visual observation of macroscopic aspect, changes in weight and the quantity of sulfate that remains on the surface have been measured. Also properties related with water have been measured after the test to determine if there have been any changes in the hydrophobic characteristics.

En el presente artículo se estudia el comportamiento de muestras de cinco tipos de piedra utilizados en catedrales andaluzas, tratadas con seis productos hidrófugos, sometiéndolas a un ensayo acelerado de alteración en atmósfera contaminada con SO₂ . Para evaluar la alteración, además de la observación visual de las manifestaciones macroscópicas, se ha medido la variación de peso de las muestras expuestas y la cantidad de sulfato que permanece en la superficie tras el ensayo. Así mismo, se han detectado los cambios experimentados en las propiedades hidrófugas conferidas por los tratamientos, mediante la medida de propiedades relacionadas con el movimiento del agua.

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

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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.

Daily Cycle of Air Temperature and Surface Temperature in Stone Forest

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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

汉魏石经杂考%Miscellaneous Research on Han and Wei Stone Classics

Institute of Scientific and Technical Information of China (English)

王东洋

2017-01-01

汉魏石经包括东汉熹平石经、《典论》石经和正始石经，三者均开刻于当时的京城洛阳，在中国文化史上具有重要意义。汉魏石经由朝廷下诏刊刻，立于太学，供天下儒生观瞻临摹。在纸质书写材料尚未普及的汉魏时期，汉魏石经起到了统一经学、保存文化、宣扬教化的作用。%Han and Wei Stone Classics with Xiping Stone classics,Dianlun Stone classics and Zhengshi Stone classics were carved in Luoyang City,has great significance in the history of Chinese culture.Under the royal order,Han and Wei Stone Classics were inscribed and erected in the Imperial College for the confucian scholars to learn and copy.In view of the underpopularization of paper writing material,Han and Wei Stone Classics played the role of unifying confucian classics,preserving culture and preaching and teaching.

Neutron radiography and X-ray computed tomography for quantifying weathering and water uptake processes inside porous limestone used as building material

International Nuclear Information System (INIS)

Dewanckele, J.; De Kock, T.; Fronteau, G.; Derluyn, H.; Vontobel, P.; Dierick, M.; Van Hoorebeke, L.; Jacobs, P.; Cnudde, V.

2014-01-01

Euville and Savonnières limestones were weathered by acid test and this resulted in the formation of a gypsum crust. In order to characterize the crystallization pattern and the evolution of the pore structure below the crust, a combination of high resolution X-ray computed tomography and SEM–EDS was used. A time lapse sequence of the changing pore structure in both stones was obtained and afterwards quantified by using image analysis. The difference in weathering of both stones by the same process could be explained by the underlying microstructure and texture. Because water and moisture play a crucial role in the weathering processes, water uptake in weathered and non-weathered samples was characterized based on neutron radiography. In this way the water uptake was both visualized and quantified in function of the height of the sample and in function of time. In general, the formation of a gypsum crust on limestone slows down the initial water uptake in the materials. - Highlights: • Time lapse sequence in 3D of changing pore structures inside limestone • A combination of X-ray CT, SEM and neutron radiography was used. • Quantification of water content in function of time, height and weathering • Characterization of weathering processes due to gypsum crystallization

[Gallbladder Stone Types in Patients with Cholelithiasis and Clonorchis sinensis Infection in the Endemic Area of Clonorchiasis].

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Ma, Rui-hong; Qiao, Tie; Luo, Zhen-liang; Luo, Xiao-bing; Zheng, Pei-ming; Yang, Liu-qing

2015-06-01

To investigate the relationship between Clonorchis sinensis infection and the gallbladder stone type in patients with cholelithiasis in the endemic area of clonorchiasis. Gallbladder stones were collected from 598 patients with cholelithiasis through minimally invasive gallbladder-preserving cholelithotomy in the Sixth People's Hospital of Nansha District from May 2009 to October 2012. The stone samples were analyzed for composition by Fourier transform infrared spectroscopy to identify their types. The Clonorchis sinensis eggs were detected in the stones by microscopic examination, and the detection rates of eggs were calculated for different stone types. Then the clinical characteristics and biochemical indicators were compared among patients with different types of stones, as well as between Clonorchis sinensis egg-positive and -negative patients with the calcium-carbonate type of stones. Some calcium-carbonate stones positive for Clonorchis sinensis eggs were randomly selected for further scanning electron microscopy (SEM) examination. Of the stones from 598 patients, 234 (39.1%) were cholesterol type, 133 (22.2%) bile pigment type, 112(18.7%) calcium-carbonate type, 86 (14.4%) mixed types and 33(5.5%) were others. The detection rate of Clonorchis sinensis eggs in these types was 6% (15/234), 44% (59/133), 60% (67/112), 36% (31/ 86) and 30% (10/33), respectively, being highest in calcium-carbonate stones while lowest in cholesterol stones. The Co2-combining power of the plasma was higher in patients with calcium-carbonate and mixed stones than in those with cholesterol stones (P Clonorchis sinensis eggs to calcium-carbonate crystals. The infection rate of Clonorchis sinensis is higher in patients with calcium-carbonate gallbladder stones than in those with other types of stones.

4D imaging and quantification of pore structure modifications inside natural building stones by means of high resolution X-ray CT.

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Dewanckele, J; De Kock, T; Boone, M A; Cnudde, V; Brabant, L; Boone, M N; Fronteau, G; Van Hoorebeke, L; Jacobs, P

2012-02-01

Weathering processes have been studied in detail for many natural building stones. The most commonly used analytical techniques in these studies are thin-section petrography, SEM, XRD and XRF. Most of these techniques are valuable for chemical and mineralogical analysis of the weathering patterns. However, to obtain crucial quantitative information on structural evolutions like porosity changes and growth of weathering crusts in function of time, non-destructive techniques become necessary. In this study, a Belgian historical calcareous sandstone, the Lede stone, was exposed to gaseous SO(2) under wet surface conditions according to the European Standard NBN EN 13919 (2003). Before, during and after the strong acid test, high resolution X-ray tomography has been performed to visualize gypsum crust formation to yield a better insight into the effects of gaseous SO(2) on the pore modification in 3D. The tomographic scans were taken at the Centre for X-ray Tomography at Ghent University (UGCT). With the aid of image analysis, partial porosity changes were calculated in different stadia of the process. Increasing porosity has been observed visually and quantitatively below the new superficial formed layer of gypsum crystals. In some cases micro-cracks and dissolution zones were detected on the grain boundaries of quartz. By using Morpho+, an in-house developed image analysis program, radial porosity, partial porosity, ratio of open and closed porosity and equivalent diameter of individual pore structures have been calculated. The results obtained in this study are promising for a better understanding of gypsum weathering mechanisms, porosity changes and patterns on natural building stones in four dimensions. Copyright © 2011 Elsevier B.V. All rights reserved.

Sialendoscope-assisted transoral removal of hilo-parenchymal sub-mandibular stones: surgical results and subjective scores.

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Capaccio, P; Gaffuri, M; Rossi, V; Pignataro, L

2017-04-01

It has been suggested that a conservative trans-oral approach to proximal and hilo-parenchymal submandibular stones (HPSMS) is a valid alternative to the more frequently used sialadenectomy. The aim of this study was to evaluate the surgical, ultrasonographic and patients' subjective outcomes of results of the trans-oral removal of HPSMS. Between January 2003 and September 2015, sialendoscope-assisted trans-oral surgery was used to remove symptomatic, large (> 7 mm), fixed and palpable HPSMS from 479 patients under general anaesthesia. All patients were followed clinically and ultrasonographically to investigate symptom relief and recurrence of stones, and were telephonically interviewed to assess saliva-related subjective outcomes with a questionnaire. Stones were successfully removed from 472 patients (98.5%); the seven failures (1.5%) concerned pure parenchymal stones. One year after the procedure, 408 patients (85.1%) were symptom free, 59 (12.3%) had recurrent obstructive symptoms and 12 (2.6%) had recurrent infections. Of the 54 patients who developed a recurrent stone (11.2%), 52 underwent a second procedure: 29 interventional sialendoscopies, two sialendoscope-assisted intra-corporeal pneumatic lithotripsy, eight secondary transoral surgery to remove residual stones, six a cycle of extra-corporeal lithotripsy and seven submandibular sialadenectomy. Most patients (75.2%) reported mild surgery-related pain. The symptoms of 454 patients (94.8%) improved after adjunctive treatment and, at the end of follow-up, the affected gland was preserved in 98.5% of patients. A sialendoscope-assisted trans-oral removal of large HPSMS is a safe, effective, conservative surgical procedure, and functional preservation of the main duct and parenchyma of the obstructed gland allows sialendoscopic access through the natural ostium in case of recurrence. Combining a trans-oral approach with other minimally invasive, conservative procedures ensures symptomatic relief and salivary

Purbeck Stone - A possible Global Heritage Stone from England

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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

Humidity sorption on natural building stone

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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.

Kidney Stones (For Parents)

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... 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 ...

Conservation and restoration of natural building stones monitored through non-destructive X-ray computed tomography

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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

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.

Performance evaluation of two protective treatments on salt-laden limestones and marble after natural and artificial weathering.

Science.gov (United States)

Salvadori, Barbara; Pinna, Daniela; Porcinai, Simone

2014-02-01

Salt crystallization is a major damage factor in stone weathering, and the application of inappropriate protective products may amplify its effects. This research focuses on the evaluation of two protective products' performance (organic polydimethylsiloxane and inorganic ammonium oxalate (NH4)2(COO)2·H2O) in the case of a salt load from behind. Experimental laboratory simulations based on salt crystallization cycles and natural weathering in an urban area were carried out. The effects were monitored over time, applying different methods: weight loss evaluation, colorimetric and water absorption by capillarity measurements, stereomicroscope observations, FTIR and SEM-EDS analyses. The results showed minor impact exerted on the short term on stones, particularly those treated with the water repellent, by atmospheric agents compared to salt crystallization. Lithotypes with low salt load (Gioia marble) underwent minor changes than the heavily salt-laden limestones (Lecce and Ançã stones), which were dramatically damaged when treated with polysiloxane. The results suggest that the ammonium oxalate treatment should be preferred to polysiloxane in the presence of soluble salts, even after desalination procedures which might not completely remove them. In addition, the neo-formed calcium oxalate seemed to effectively protect the stone, improving its resistance against salt crystallization without occluding the pores and limiting the superficial erosion caused by atmospheric agents.

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....

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

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....

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.

Rapid formation of cholesterol crystals in gallbladder bile is associated with stone recurrence after laparoscopic cholecystotomy.

Science.gov (United States)

Jüngst, D; del Pozo, R; Dolu, M H; Schneeweiss, S G; Frimberger, E

1997-03-01

Laparoscopic cholecystotomy (LCT) with subsequent extraction of gallstones and primary closure of the gallbladder has been introduced as an alternative therapy for patients with cholecystolithiasis and preserved gallbladder function. However, stone recurrence has to be considered as a major drawback that might be related to lithogenic factors of gallbladder bile or the composition of gallbladder stones. Therefore, these were studied in relation to stone recurrence within an observation period of 1 to 5 years (median, 3.6 years) in 50 patients after LCT. The concentrations of total and individual bile acids, phospholipids, cholesterol, total lipids, mucin, protein, and the cholesterol saturation indices in gallbladder bile were not significantly different between 10 patients with and 40 patients without stone recurrence. However, the crystal observation time was significantly (P < .02) shorter (range, 1-2 days; median, 1.5) in the bile of patients with stone recurrence compared to those without (range, 1-21 days, median 3.5). Moreover, all 10 stone recurrences were observed in the 28 patients with a crystal observation time in the bile of less than or equal to 2 days (approximate annual risk: 12%-15%), and no recurrences were observed in the 22 patients with a crystal observation time greater than 2 days (P < .0001) or in patients with pigment stones. The rapid formation of cholesterol monohydrate crystals in bile seems to be the major risk factor for recurrent stones after LCT. These are most likely cholesterol stones and, therefore, are amenable to oral bile-acid prevention or treatment.

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.

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.

Conservation of Stone Cladding on the FAÇADE of Royal Palace in Caserta

Science.gov (United States)

Titomanlio, I.

2013-07-01

The beauty of cultural heritage and monumental architecture, is often linked to their non-structural elements and decorative stones façades cladding. The collapse of these elements causes significant consequences that interest the social, the economic, the historical and the technical fields. Several regulatory documents and literature studies contain methods to address the question of relief and of the risk analysis and due to the non - structural stones security. Among the references are widespread international regulatory documents prepared by the Federal Emergency Management Agency of the United States by Applied Technology Council and California. In Italy there are some indications contained in the Norme Tecniche per le Costruzioni and the Direttiva del Presidente del Consiglio dei Ministri in 2007, finalize to the reduction of seismic risk assessment of cultural heritage. The paper, using normative references and scientific researches, allows to analyze on Royal Palace of Caserta the safety and the preservation of cultural heritage and the vulnerability of non-structural stones façade cladding. Using sophisticated equipments of Laboratory ARS of the Second University of Naples, it was possible to analyze the collapse of stone elements due to degradation caused by natural phenomena of deterioration (age of the building, type of materials, geometries , mode of fixing of the elements themselves). The paper explains the collapse mechanisms of stones façade cladding of Luigi Vanvitelli Palace.

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...

The erosion of carbonate stone by acid rain: Laboratory and field investigations

Science.gov (United States)

Baedecker, P.A.; Reddy, M.M.

1993-01-01

One of the goals of research on the effects of acidic deposition on carbonate stone surfaces is to define the incremental impact of acidic deposition relative to natural weathering processes on the rate of carbonate stone erosion. If rain that impacts carbonate stone surfaces is resident on the surface long enough to approach chemical equilibrium, the incremental effect of hydrogen ion is expected to be small (i.e., 6% for a rain of pH 4.0). Under nonequilibrium (i.e., high flow rate) conditions, kinetic considerations suggest that the incremental effect of hydrogen ion deposition could be quite significant. Field run-off experiments involving the chemical analysis of rain collected from inclined stone slabs have been used to evaluate stone dissolution processes under ambient conditions of wet and dry deposition of acidic species. The stoichiometry of the reaction of stone with hydrogen ion is difficult to define from the field data due to scatter in the data attributed to hydrodynamic effects. Laboratory run-off experiments show that the stoichiometry is best defined by a reaction with H+ in which CO2 is released from the system. The baseline effect caused by water in equilibrium with atmospheric CO2 is identical in the field and in laboratory simulation. The experiments show that the solutions are close enough to equilibrium for the incremental effect of hydrogen ion to be minor (i.e., 24% for marble for a rain of pH 4.0) relative to dissolution due to water and carbonic acid reactions. Stone erosion rates based on physical measurement are approximately double the recession rates that are due to dissolution (estimated from the observed calcium content of the run-off solutions). The difference may reflect the loss of granular material not included in recession estimates based on the run-off data. Neither the field nor the laboratory run-off experiments indicate a pH dependence for the grain-removal process.

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.

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...

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.

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 ...

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.

Climatology of salt transitions and implications for stone weathering

International Nuclear Information System (INIS)

Grossi, C.M.; Brimblecombe, P.; Menendez, B.; Benavente, D.; Harris, I.; Deque, M.

2011-01-01

This work introduces the notion of salt climatology. It shows how climate affects salt thermodynamic and the potential to relate long-term salt damage to climate types. It mainly focuses on specific sites in Western Europe, which include some cities in France and Peninsular Spain. Salt damage was parameterised using the number of dissolution-crystallisation events for unhydrated (sodium chloride) and hydrated (sodium sulphate) systems. These phase transitions have been calculated using daily temperature and relative humidity from observation meteorological data and Climate Change models' output (HadCM3 and ARPEGE). Comparing the number of transitions with meteorological seasonal data allowed us to develop techniques to estimate the frequency of salt transitions based on the local climatology. Results show that it is possible to associate the Koeppen-Geiger climate types with potential salt weathering. Temperate fully humid climates seem to offer the highest potential for salt damage and possible higher number of transitions in summer. Climates with dry summers tend to show a lesser frequency of transitions in summer. The analysis of temperature, precipitation and relative output from Climate Change models suggests changes in the Koeppen-Geiger climate types and changes in the patterns of salt damage. For instance, West Europe areas with a fully humid climate may change to a more Mediterranean like or dry climates, and consequently the seasonality of different salt transitions. The accuracy and reliability of the projections might be improved by simultaneously running multiple climate models (ensembles). - Research highlights: → We introduce the notion of salt climatology for heritage conservation. → Climate affects salt thermodynamics on building materials. → We associate Koeppen-Geiger climate types with potential salt weathering. → We offer future projections of salt damage in Western Europe due to climate change. → Humid climate areas may change to

Climatology of salt transitions and implications for stone weathering

Energy Technology Data Exchange (ETDEWEB)

Grossi, C.M., E-mail: c.grossi-sampedro@uea.ac.uk [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Brimblecombe, P. [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Menendez, B. [Geosciences et Environnement Cergy, Universite de Cergy-Pontoise 95031 Cergy-Pontoise cedex (France); Benavente, D. [Lab. Petrologia Aplicada, Unidad Asociada UA-CSIC, Dpto. Ciencias de la Tierra y del Medio Ambiente, Universidad de Alicante, Alicante 03080 (Spain); Harris, I. [Climatic Research Unit, School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Deque, M. [Meteo-France/CNRM, CNRS/GAME, 42 Avenue Coriolis, F-31057 Toulouse, Cedex 01 (France)

2011-06-01

This work introduces the notion of salt climatology. It shows how climate affects salt thermodynamic and the potential to relate long-term salt damage to climate types. It mainly focuses on specific sites in Western Europe, which include some cities in France and Peninsular Spain. Salt damage was parameterised using the number of dissolution-crystallisation events for unhydrated (sodium chloride) and hydrated (sodium sulphate) systems. These phase transitions have been calculated using daily temperature and relative humidity from observation meteorological data and Climate Change models' output (HadCM3 and ARPEGE). Comparing the number of transitions with meteorological seasonal data allowed us to develop techniques to estimate the frequency of salt transitions based on the local climatology. Results show that it is possible to associate the Koeppen-Geiger climate types with potential salt weathering. Temperate fully humid climates seem to offer the highest potential for salt damage and possible higher number of transitions in summer. Climates with dry summers tend to show a lesser frequency of transitions in summer. The analysis of temperature, precipitation and relative output from Climate Change models suggests changes in the Koeppen-Geiger climate types and changes in the patterns of salt damage. For instance, West Europe areas with a fully humid climate may change to a more Mediterranean like or dry climates, and consequently the seasonality of different salt transitions. The accuracy and reliability of the projections might be improved by simultaneously running multiple climate models (ensembles). - Research highlights: {yields} We introduce the notion of salt climatology for heritage conservation. {yields} Climate affects salt thermodynamics on building materials. {yields} We associate Koeppen-Geiger climate types with potential salt weathering. {yields} We offer future projections of salt damage in Western Europe due to climate change. {yields} Humid

Restoration of severely weathered wood

Science.gov (United States)

R. Sam. Williams; Mark. Knaebe

2000-01-01

Severely weathered window units were used to test various restoration methods and pretreatments. Sanded and unsanded units were pretreated with a consolidant or water repellent preservative, finished with an oil- or latex-based paint system, and exposed outdoors near Madison, WI, for five years. Pretreatments were applied to both window sashes (stiles and rails) and...

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.

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.

Comparative study of the variation of the hydric properties and aspect of natural stone and brick after the application of 4 types of anti-graffiti

Directory of Open Access Journals (Sweden)

García, O.

2010-02-01

Full Text Available In this article a comparative study of the behaviour of different commercial anti-graffiti on natural stone and brick is presented. 8 different European substrates were selected and 4 commercial anti-graffiti of different chemical nature were applied on these substrates. The variations of their hydric properties and aspect (colour and gloss with regard to the untreated substrates were later studied in the laboratory. The results obtained permitted to assess the suitability of 4 of the main types of chemical formulations employed to be used as anti-graffiti. This study concludes that the sacrificial anti-graffiti with polymeric paraffins in its composition presents the lowest reductions of the hydric properties of the studied substrates, being also the variations in colour the least perceptible.

En este artículo se presenta un estudio comparativo del comportamiento de diferentes tipos de anti-graffiti comerciales sobre piedra natural y ladrillo. Para ello se seleccionaron 8 tipos de sustratos porosos de diferentes países europeos, sobre los que se aplicaron 4 anti-graffiti de distinta naturaleza química. Posteriormente se estudiaron las variaciones en sus propiedades hídricas y de aspecto (color y brillo con respecto a los sustratos no tratados, en el laboratorio. Los resultados obtenidos han permitido evaluar la idoneidad de 4 de los principales tipos de formulaciones químicas más frecuentemente utilizadas como anti-graffiti sobre sustratos porosos. El estudio concluye que el antigraffiti de sacrificio de composición parafínica es el producto que reduce en menor medida las propiedades hídricas de los sustratos porosos estudiados, y que menores cambios de color produce en los mismos.

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.

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

Clinical application of duodenum-preserving pancreatic head resection

OpenAIRE

ZHOU Songqiang

2018-01-01

Objective To investigate the indications and therapeutic effect of duodenum-preserving pancreatic head resection (DPPHR). Methods A retrospective analysis was performed for the clinical data of 17 patients who underwent DPPHR in Fujian Provincial Hospital from January 2013 to February 2017. Among these patients, 6 had chronic pancreatitis with pancreatic duct stones, 2 had chronic pancreatitis with pancreatic pseudocyst, 3 had solid pseudopapillary tumor of the pancreatic head, 3 had intraduc...

Briefing highlights space weather risks to GPS

Science.gov (United States)

Tretkoff, Ernie

2011-07-01

Solar storms, which are expected to increase as the Sun nears the most active phase of the solar cycle, can disrupt a variety of technologies on which society relies. Speakers at a 22 June briefing on Capitol Hill in Washington, D. C., focused on how space weather can affect the Global Positioning System (GPS), which is used in a wide range of industries, including commercial air travel, agriculture, national security, and emergency response. Rocky Stone, chief technical pilot for United Airlines, noted that GPS allows more aircraft to be in airspace, saves fuel, and helps aircraft move safely on runways. “Improvements in space weather forecasting need to be pursued,” he said. Precision GPS has also “changed the whole nature of farming,” said Ron Hatch, Director of Navigation Systems, NavCom Technology/John Deere. GPS makes it possible for tractors to be driven in the most efficient paths and for fertilizer and water to be applied precisely to the areas that most need them. Space weather-induced degradation of GPS signals can cause significant loss to farms that rely on GPS. Elizabeth Zimmerman, Deputy Associate Administrator for the Office of Response and Recovery at the Federal Emergency Management Agency (FEMA), described how FEMA relies on GPS for disaster recovery. The agency is developing an operations plan for dealing with space weather, she said.

The development of anti-heat stress clothing for construction workers in hot and humid weather.

Science.gov (United States)

Chan, Albert P C; Guo, Y P; Wong, Francis K W; Li, Y; Sun, S; Han, X

2016-04-01

The purpose of this study was to develop anti-heat stress clothing for construction workers in hot and humid weather. Following DeJonge's functional clothing design process, the design situation was explored, including clothing fabric heat/moisture transporting properties and UV protection and the aspects of clothing ergonomic design (mobility, convenience, and safety). The problem structure was derived from the results of the surveys in three local construction sites, which agreed well with the task requirements and observations. Specifications were consequently described and 30 commercially available fabrics were identified and tested. Fabric testing data and design considerations were inputted in S-smart system to predict the thermal functional performance of the clothing. A new uniform prototype was developed and evaluated. The results of all measurements suggest that the new uniform which incorporated fabrics with superior heat/moisture transporting properties and loose-fitting design could reduce the workers' heat stress and improve their comfort and work performance. Practitioner Summary: The construction workers' uniform currently used in Hong Kong during summer was unsatisfactory. Following DeJonge's functional clothing design process, an anti-heat stress uniform was developed by testing 30 fabrics and predicting clothing thermal functional performance using S-smart system. The new uniform could reduce the workers' heat stress and improve their comfort and work performance.

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...

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.

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.

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.

Colorado Yule Marble; building stone of the Lincoln Memorial

Science.gov (United States)

McGee, Elaine S.

1999-01-01

The Colorado Yule marble, quarried in Marble, Colo., is a very pure white marble, and it has been widely acclaimed for its quality and purity. This marble has been used for many prominent buildings; one of the most notable is the Lincoln Memorial in Washington, D.C., built nearly 80 years ago. Although most of the marble in the memorial appears to be in very good condition, some of the stones have developed pronounced surficial roughness and show a significant loss of carved details and rounded edges compared with adjacent stones. Because adjacent blocks of marble receive nearly identical exposure to weathering agents that cause deterioration of the marble, it seems very likely that this pronounced difference in durability of adjacent stones arises from some inherent characteristic of the marble. The Colorado Yule marble is a nearly pure calcite marble with minor inclusions of mica, quartz, and feldspar. Compositions of the calcite and the inclusion phases in the marble are typical for those phases. The calcite grains that compose the marble are irregularly shaped and range from 100 to 600 micrometers in diameter. The texture of the marble is even, with a slight preferred directional elongation that is visible when the marble is cut in certain directions. Physical tests of the marble show that its strength is comparable to that of other marbles typically used in buildings. Variations in the durability of the marble, like those seen at the Lincoln Memorial, are not related to variations in calcite composition or to the presence of inclusions in the marble. Most likely, the variations arise from differences in the calcite grain boundaries and the degree to which the grains interlock with one another. Weak grain boundaries that permit water or solutions to penetrate into the marble and dissolve the calcite grains at their edges cause the marble to disaggregate or ?sugar.? Subtle differences in texture that occur in the marble from various parts of the quarry probably

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....

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.

Effects of acid deposition on dissolution of carbonate stone during summer storms in the Adirondack Mountains, New York, 1987-89

Science.gov (United States)

Schuster, Paul F.; Reddy, Michael M.; Sherwood, S.I.

1994-01-01

This study is part of a long-term research program designed to identify and quantify acid rain damage to carbonate stone. Acidic deposition accelerates the dissolution of carbonate-stone monuments and building materials. Sequential sampling of runoff from carbonate-stone (marble) and glass (reference) microcatchments in the Adirondack Mountains in New York State provided a detailed record of the episodic fluctuations in rain rate and runoff chemistry during individual summer storms. Rain rate and chemical concentrations from carbonate-stone and glass runoff fluctuated three to tenfold during storms. Net calcium-ion concentrations from the carbonatestone runoff, a measure of stone dissolution, typically fluctuated twofold during these storms. High net sulfate and net calcium concentrations in the first effective runoff at the start of a storm indicated that atmospheric pollutants deposited on the stone surface during dry periods formed calcium sulfate minerals, an important process in carbonate stone dissolution. Dissolution of the carbonate stone generally increased up to twofold during coincident episodes of low rain rate (less than 5 millimeters per hour) and decreased rainfall (glass runoff) pH (less than 4.0); episodes of high rain rate (cloudbursts) were coincident with a rapid increase in rainfall pH and also a rapid decrease in the dissolution of carbonate-stone. During a storm, it seems the most important factors causing increased dissolution of carbonate stone are coincident periods of low rain rate and decreased rainfall pH. Dissolution of the carbonate stone decreased slightly as the rain rate exceeded about 5 millimeters per hour, probably in response to rapidly increasing rainfall pH during episodes of high rain rate and shorter contact time between the runoff and the stone surface. High runoff rates resulting from cloudbursts remove calcium sulfate minerals formed during dry periods prior to storms and also remove dissolution products formed in large

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

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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

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...

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.

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.

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 .

A comparison of preservative-free diclofenac and preserved diclofenac eye drops after cataract surgery in patients with diabetic retinopathy.

Science.gov (United States)

Yasuda, Kanako; Miyazawa, Akiko; Shimura, Masahiko

2012-06-01

The aim of this study was to compare the anti-inflammatory efficacy of preservative-free and preserved 0.1% diclofenac eye drops for the management of postoperative inflammation after cataract surgery in patients with nonproliferative diabetic retinopathy and in normal controls. Forty-two diabetic patients and 50 normal control patients who underwent small-incision phacoemulsification cataract surgery bilaterally received topical preservative-free diclofenac in 1 eye and preserved diclofenac in the other eye. The corrected distance visual acuity (CDVA) as determined by a logarithm of the minimum angle of resolution (logMAR) chart, intraocular pressure (IOP), foveal thickness (FT) using optical coherence tomography (OCT), and the anterior chamber flare (ACF) score measured with a laser flare cell meter were monitored for 12 weeks after surgery. In the eyes with diabetic retinopathy, there were no significant differences in CDVA, IOP, FT, and ACF score between the right and left eyes at the initial exam. After cataract surgery, changes in CDVA, IOP, and FT were not influenced by the preservative in the diclofenac eye drops. In contrast, the ACF score in the eyes treated with preserved diclofenac showed slower recovery from postoperative inflammation than the eyes treated with preservative-free diclofenac. In the normal control eyes, similar but milder changes were observed in each of the clinical parameters. Because preservative suppressed the anti-inflammatory efficacy of topical diclofenac after cataract surgery, preservative-free diclofenac may have an improved safety profile during postoperative treatment, especially in patients with diabetic retinopathy.

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)

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.

Kidney stone formation and antioxidant effects of Cynodon dactylon decoction in male Wistar rats.

Science.gov (United States)

Golshan, Alireza; Hayatdavoudi, Parichehr; Hadjzadeh, Mousa Al-Reza; Khajavi Rad, Abolfazl; Mohamadian Roshan, Nema; Abbasnezhad, Abbasali; Mousavi, Seyed Mojtaba; Pakdel, Roghayeh; Zarei, Batool; Aghaee, Azita

2017-01-01

The antioxidant capacity impairs in kidney and urinary bladder of animals with stone disease. Herbal medicine can improve the antioxidant condition of renal tissue. Cynodon dactylon ( C. dactylon ) is a medicinal plant with antioxidative and diuretic properties and different preparations of this plant have shown promising effects in stone disease. Assessment of the whole plant decoction to prevent kidney stone disease as well as its antioxidant effects was the aim of this paper. Fifty male Wistar rats were randomly divided into 5 experimental groups (n=10). One group was left without treatment and four groups received ethylene glycol (1% v/v) in drinking water for 6 weeks. Three doses of Cynodon dactylon aqueous decoction (12.5, 50 and 200 mg/kg BW) were added to the drinking water of groups 3-5. Finally, water intake, 24-hour urine volume, MDA, total thiol concentration and FRAP value were measured in the serum and kidney tissues. The CaOx depositions were evaluated by hematoxylin and eosin staining. Compared to the ethylene glycol-treated group, 200 mg/kg C. dactylon , lowered stone incidents, decreased urine volume, increased FRAP/g Cr (43%) and thiol content (p<0.05) with no significant alteration of water intake, MDA decreased significantly compared to C. dactylon 12.5 (p<0.01). Kidney weight increased and body weight decreased in ethylene glycol-treated group compared to the control group (p<0.05). A minimum dose of 200 mg/kg C. dactylon reduced stone formation and simultaneously increased total antioxidant power of serum and preserved MDA content and water.

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.

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

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.

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.

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.

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).

Anti-Thixotropic Analysis of Pipeline Metal Losses in Welded ...

African Journals Online (AJOL)

Anti-Thixotropic Analysis of Pipeline Metal Losses in Welded Locations due to ... by the presence of large slurry of aggregates of sand stones in the pipelines. ... This investigation showed that the sand trap built insitu to sieve the sand and ...

Investigation of salt distribution in porous stone material using paper pulp poultices under laboratory condititions and on site

Science.gov (United States)

Egartner, Isabel; Sass, Oliver

2016-04-01

The presented investigation is part of a longer-term project which deals with the influence of salt and moisture on weathering of historic stonework. The main investigation object in the field is a part of the 300 hundred year old boundary wall of the Worchester College in Oxford, UK. A range of non-destructive techniques were applied in course of field campaigns, e.g. mapping of weathering phenomena; handheld moisture sensors; and salt sampling by paper pulp poultices. In a second step we investigated the behaviour and distribution of water and salt solution in a porous material, similar to the limestone of the College wall, under laboratory condititions. Limestone cube samples (5x5x5 cm) were soaked first with ultrapure H2O and second with different concentration of saline solutions of NaCl and Na2SO4. During the dehydration process of the stone cubes a multi-method approach including sampling by drilling, paper pulp poultices, handheld moisture sensor, conductivity sensor and Ion Chromatography (IC) were applied to investigate the moisture and salt content and distribution within the samples. The laboratory analyses were carried out at the department of applied geoscience of the Technical University of Graz, Austria. The main aim was to investigate the effectivity of the paper pulp poultices in soaking up salts from the stone samples and to use the results of the laboratory analysis to interpret and calibrate the field work results from the College wall in Oxford. Keywords: Salt weathering, paper pulp poultices, cultural heritage, field work and laboratory investigation

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.

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.

A new method for making artificially weathered stone specimens for testing of conservation treatments

NARCIS (Netherlands)

Lubelli, B.A.; Hees, R.P.J. van; Nijland, T.G.; Bolhuis, J.

2015-01-01

tThe application of new consolidating products on the surface of weathered materials is a common inter-vention technique in conservation practice. Due to the difficulty of producing artificially weatheredsubstrates in a reproducible way, the effect of consolidating products in laboratory is

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

Selenium in Paleozoic stone coal (carbonaceous shale) as a significant source of environmental contamination in rural southern China

Science.gov (United States)

Belkin, H. E.; Luo, K.

2012-04-01

Selenium occurs in high concentrations (typically > 10 and up to 700 ppm) in organic-rich Paleozoic shales and cherts (called "stone coal" - shíméi), in southern China. Stone coals are black shales that formed in anoxic to euxinic environments and typically contain high concentrations of organic carbon, are enriched in various metals such as V, Mo, Pb, As, Cr, Ni, Se, etc., and are distinguished from "humic" coal in the Chinese literature. We have examined stone coal from Shaanxi, Hubei, and Guizhou Provinces, People's Republic of China and have focused our study on the mode of occurrence of Se and other elements (e.g. As, Pb, etc.) hazardous to human health. Scanning electron microscope, energy-dispersive analysis and electron microprobe wave-length dispersive spectroscopy were used to identify and determine the composition of host phases observed in the stone coals. Native selenium, Se-bearing pyrite and other sulfides are the hosts for Se, although we cannot preclude an organic or clay-mineral association. Stone coals are an important source of fuel (reserves over 1 billion tonnes), both domestically and in small industry, in some rural parts of southern China and present significant environmental problems for the indigenous population. The stone coals create three main environmental problems related to Se pollution. First, the residual soils formed on stone coal are enriched in Se and other metals contained in the stone coals and, depending on the speciation and bioavailability of the metals, may enrich crops and vegetation grown on them. Second, weathering and leaching of the stone coal contaminates the local ground water and/or surface waters with Se and other metals. Third, the local population uses the stone coal as a source of fuel, which releases the more volatile elements (Se and As) into the atmosphere in the homes. The ash will be extremely enriched with the balance of the heavy metal suite. Disposal of the ash on agricultural lands or near water

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, ...

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)

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.

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.

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...

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

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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.

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.

Our results with uterus-preserving abdominal approach and simultaneous anti-incontinence surgery in the management of advanced uterovaginal prolapse

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Fikret Fatih Önol

2010-06-01

Full Text Available Objectives: Vaginal hysterectomy is generally performed in the management of advanced uterovaginal prolapse. However, removal of the uterus may damage the integrity of pelvic floor dynamics with an increased risk for voiding dysfunction. In this study, we reviewed our results with uterus-preserving abdominal sacrohysteropexy (ASCH technique.\tDesign: Women with advanced (POP-Q stage ≥3 uterovaginal prolapse who underwent ASCH were evaluated with quality of life (P-QOL and incontinence (ICIQ-SF questionnaires, pelvic examination, urodynamic studies, and a comparison of preoperative and postoperative findings was planned.\tSetting: Clinics of Urology and Obstetrics and Gynecology at Sakarya Training and Research Hospital.\tPatients: Twelve women who that underwent uterus-preserving ASCH between 2007 and 2008.\tInterventions: Rectovaginal and vesicovaginal planes were dissected until the levator plate, followed by interposition and fixation of self-cut prolene meshes to anterior and posterior vaginal walls with non-absorbable sutures. The anterior mesh was cut in the midline at the cervical level producing 2 legs, which were transferred posteriorly under the broad ligament. Promontofixation was performed after retroperitoneal transfer of all meshes. Eight and 2 patients received transobturator tape (TOT and Burch procedures, respectively.\tResults: Mean operative time was 156 min, mean hospitalization was 2.3 days. A normal anatomically supported uterus and cervix was achieved in all patients with a mean follow-up of 12.8 months with evidence of recurrent rectocele in 1 patient. Quality of life measures and incontince scores improved significantly in all patients after the procedure. De-novo stress incontinence developed in 1 of the 2 patients who did not receive anti-incontinence surgery initially. De-novo urge symptoms or vaginal mesh erosion were not evident in any case.\tConclusions: Uterus-preserving ASCH and simultaneous anti

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.

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.

Dietary treatment of urinary risk factors for renal stone formation. A review of CLU Working Group.

Science.gov (United States)

Prezioso, Domenico; Strazzullo, Pasquale; Lotti, Tullio; Bianchi, Giampaolo; Borghi, Loris; Caione, Paolo; Carini, Marco; Caudarella, Renata; Ferraro, Manuel; Gambaro, Giovanni; Gelosa, Marco; Guttilla, Andrea; Illiano, Ester; Martino, Marangella; Meschi, Tiziana; Messa, Piergiorgio; Miano, Roberto; Napodano, Giorgio; Nouvenne, Antonio; Rendina, Domenico; Rocco, Francesco; Rosa, Marco; Sanseverino, Roberto; Salerno, Annamaria; Spatafora, Sebastiano; Tasca, Andrea; Ticinesi, Andrea; Travaglini, Fabrizio; Trinchieri, Alberto; Vespasiani, Giuseppe; Zattoni, Filiberto

2015-07-07

Diet interventions may reduce the risk of urinary stone formation and its recurrence, but there is no conclusive consensus in the literature regarding the effectiveness of dietary interventions and recommendations about specific diets for patients with urinary calculi. The aim of this study was to review the studies reporting the effects of different dietary interventions for the modification of urinary risk factors in patients with urinary stone disease. A systematic search of the Pubmed database literature up to July 1, 2014 for studies on dietary treatment of urinary risk factors for urinary stone formation was conducted according to a methodology developed a priori. Studies were screened by titles and abstracts for eligibility. Data were extracted using a standardized form and the quality of evidence was assessed. Evidence from the selected studies were used to form evidence-based guideline statements. In the absence of sufficient evidence, additional statements were developed as expert opinions. General measures: Each patient with nephrolithiasis should undertake appropriate evaluation according to the knowledge of the calculus composition. Regardless of the underlying cause of the stone disease, a mainstay of conservative management is the forced increase in fluid intake to achieve a daily urine output of 2 liters. HYPERCALCIURIA: Dietary calcium restriction is not recommended for stone formers with nephrolithiasis. Diets with a calcium content ≥ 1 g/day (and low protein-low sodium) could be protective against the risk of stone formation in hypercalciuric stone forming adults. Moderate dietary salt restriction is useful in limiting urinary calcium excretion and thus may be helpful for primary and secondary prevention of nephrolithiasis. A low-normal protein intake decrease calciuria and could be useful in stone prevention and preservation of bone mass. Omega-3 fatty acids and bran of different origin decreases calciuria, but their impact on the urinary

Dietary treatment of urinary risk factors for renal stone formation. A review of CLU Working Group

Directory of Open Access Journals (Sweden)

Domenico Prezioso

2015-07-01

Full Text Available Objective: Diet interventions may reduce the risk of urinary stone formation and its recurrence, but there is no conclusive consensus in the literature regarding the effectiveness of dietary interventions and recommendations about specific diets for patients with urinary calculi. The aim of this study was to review the studies reporting the effects of different dietary interventions for the modification of urinary risk factors in patients with urinary stone disease. Materials and Methods: A systematic search of the Pubmed database literature up to July 1, 2014 for studies on dietary treatment of urinary risk factors for urinary stone formation was conducted according to a methodology developed a priori. Studies were screened by titles and abstracts for eligibility. Data were extracted using a standardized form and the quality of evidence was assessed. Results: Evidence from the selected studies were used to form evidencebased guideline statements. In the absence of sufficient evidence, additional statements were developed as expert opinions. Conclusions: General measures: Each patient with nephrolithiasis should undertake appropriate evaluation according to the knowledge of the calculus composition. Regardless of the underlying cause of the stone disease, a mainstay of conservative management is the forced increase in fluid intake to achieve a daily urine output of 2 liters. Hypercalciuria: Dietary calcium restriction is not recommended for stone formers with nephrolithiasis. Diets with a calcium content ≥ 1 g/day (and low protein-low sodium could be protective against the risk of stone formation in hypercalciuric stone forming adults. Moderate dietary salt restriction is useful in limiting urinary calcium excretion and thus may be helpful for primary and secondary prevention of nephrolithiasis. A low-normal protein intake decrease calciuria and could be useful in stone prevention and preservation of bone mass. Omega-3 fatty acids and bran of

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

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.

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.

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

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.

The Meteoritical Quincentennial: The Stone of Ensisheim 1492-1992

Science.gov (United States)

Marvin, U. B.

1992-07-01

This year marks the 500th anniversary of the fall of a meteorite at Ensisheim in Alsace. In at least two respects this event is unique in the history of meteoritics. First, this was the earliest witnessed meteorite fall in the West from which pieces are preserved. Second, it is the only meteorite of which a continuous five-century public record exists in manuscripts and books. Beginning with newsheets printed in 1492, writings about this event illuminate the evolution of ideas from a 15th century belief that stones from the sky were of miraculous origin, to an 18th century conviction that stones do not fall from the sky, to our present view that they fall in abundance, originating in interplanetary space (Marvin, 1992). This paper will highlight certain previously unexamined aspects of the story and address problems inherent in historical analysis. Unusable Maps. The fall of the stone was heralded by an explosion which, according to Sebastian Brant (1492), was heard along the valleys of the Danube, Neckar, Aare, Ill, and Rhine and in the alpine cantons of Schwyz and Uri. Contemporary maps, such as that published in The Nuremberg Chronicle of 1493, so distorted the regional geography that a fireball trajectory cannot be reconstructed on them. On modern maps, however, the areas Brant listed stretch about 150 km to the southeast of Ensisheim, a distance well within the range of sounds reported from other exploding fireballs. Newton (1891) and Marvin (1992) worked out possible trajectories that could account for the sound being heard in all named localities. This suggests that, far from exaggerating distances for dramatic effect, Brant's description may well have been accurate. If so, he compiled his information from word-of-mouth reports without reference to the rudimentary maps available in his time. The Language of Wonder. A document mounted beside the stone in the Ensisheim church stated that learned men did not know what it was: it must be supernatural, a wonder

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)

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.

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

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.

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.

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.

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.

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

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

Microscopic study of weathering of white Flemish stone from the monumental Church of Our Lady in Breda, The Netherlands

NARCIS (Netherlands)

Larbi, J.A.; Hees, R.P.J. van; Naldini, S.

2003-01-01

This paper deals with the use of an integrated microscopic method to assist in the investigation of the causes and the extent of decay of the stones and ornaments in the gothic Clurch of Out Lady in Breda, The Netherlands. The purpose of the study was to determine whether conservation measures were

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

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

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.

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.

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.

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

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)

Ultrasonic Surface Measurements for the investigation of superficial alteration of natural stones

Science.gov (United States)

Meier, Thomas; Auras, Michael; Bilgili, Filiz; Christen, Sandra; Cristiano, Luigia; Krompholz, Rolf; Mosca, Ilaria; Rose, David

2013-04-01

Seismic waveform analysis is applicable also to the centimeter and decimeter scale for non-destructive testing of pavement, facades, plaster, sculptures, or load-bearing structures like pillars. Mostly transmission measurements are performed and travel-times of first arriving P-waves are considered that have limited resolution for the upper centimeters of an object. In contrast, surface measurements are well suited to quantify superficial alterations of material properties e.g. due to weathering. A number of surface measurements have been carried out in the laboratory as well as on real structures in order to study systematically the information content of ultrasonic waveforms and their variability under real conditions. As a preposition for ultrasonic waveform analysis, reproducible, broad-band measurements have to be carried out with a definite radiation pattern and an about 1 mm accuracy of the measurement geometry. We used special coupling devices for effective ultrasonic surface measurements in the laboratory as well as at real objects. Samples of concrete with varying composition and samples of natural stone - marble, tuff, and sandstone - were repeatedly weathered and tested by ultrasonic measurements. The resistance of the samples to weathering and the penetration depth of the weathering are analyzed. Furthermore, material specific calibration curves for changes in velocities of elastic waves due to weathering can be obtained by these tests. Tests on real structures have been carried out for marble (Schlossbrücke, Berlin) and sandstone (Porta Nigra, Trier). Altogether, these test measurements show clearly that despite of the internal inhomogeneity of many real objects, their surface roughness and topography especially ultrasonic Rayleigh waves are well suited to study material alterations in the upper centimeters. Dispersion of Rayleigh waves may be inverted for shear-wave velocity as a function of depth.

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...

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.)

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...

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

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

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 ...

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...

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.

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.

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

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.

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.

An Examination of the Space Weathering Patina of Lunar Rock 76015

Science.gov (United States)

Noble, S.; Chrisoffersen, R.; Rahman, Z.

2011-01-01

Space weathering discussions have generally centered around soils but exposed rocks will also incur the effects of weathering. Rocks have much longer surface lifetimes than an individual soil grain and thus record a longer history of exposure. By studying the weathering products which have built up on a rock surface, we can gain a deeper perspective on the weathering process and better assess the relative importance of various weathering components. The weathered coating, or patina, of the lunar rock 76015 has been previously studied under SEM and also by TEM using ultramicrotome sample preparation methods. However, to really understand the products involved in creating these coatings, it is helpful to examine the patina in cross section, something which is now possible though the use of Focused Ion Beam (FIB) sample prep techniques, which allows us to preserve intact the delicate stratigraphy of the patina coating and provides a unique cross-sectional view of the space weathering process. Several samples have been prepared from the rock and the coatings are found to be quite variable in thickness and composition from one sample to the next.

Space Weather Drivers in the ACE Era

Science.gov (United States)

Vogt, M.; Puhl-Quinn, P.; Jordanova, V. K.; Smith, C. W.; Cohen, C. M.

2004-12-01

The Advanced Composition Explorer (ACE) spacecraft was launched Aug.~25, 1997 [Stone et al., 1998]. Beginning shortly after launch and continuing to the present day ACE has provided real-time data telemetry of solar wind conditions upstream of the Earth. The real-time data includes solar wind speed and density, magnetic field direction and magnitude, and a range of energetic particle intensities [Zwickl et al., 1999]. The real-time data product is provided within 5 minutes of observation and many partners from both industry and science use these data for a variety of purposes. The most common purpose of practical industrial application involves mitigation of lost services arising from magnetospheric storm activity. Many space weather efforts are directed at providing improved predictions of magnetospheric response that can be applied to real-time data in the hope of better predicting the vulnerability and required action of industry to approaching disturbances. It therefore seems prudent that following 6 years of activity including one solar maximum period we should evaluate the nature and strength of the largest disturbances observed with the hope of better assessing the industrial response. Simply put: ``Did ACE observe disturbances that were as large as those seen previously during the space age?'' If not, it may be the case that industry must evaluate its response to the real-time warnings and not become complacent by the simple act of survival. We compare the most intense space weather events of the ACE era with those recorded on the Omnitape data set spanning 40+ years of spacecraft measurements in the near-Earth environment. We compare both magnetospheric response parameters and solar wind drivers. In addition, we compare the large energetic particle events over the same time frame. Stone, E.~C., et al., Space Science Rev., 86(1-4), 357-408, 1998. Zwickl, R.~D., et al., Space Science Rev., 86(1-4), 633-648, 1998.

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.

Climatology of salt transitions and implications for stone weathering.

Science.gov (United States)

Grossi, C M; Brimblecombe, P; Menéndez, B; Benavente, D; Harris, I; Déqué, M

2011-06-01

This work introduces the notion of salt climatology. It shows how climate affects salt thermodynamic and the potential to relate long-term salt damage to climate types. It mainly focuses on specific sites in Western Europe, which include some cities in France and Peninsular Spain. Salt damage was parameterised using the number of dissolution-crystallisation events for unhydrated (sodium chloride) and hydrated (sodium sulphate) systems. These phase transitions have been calculated using daily temperature and relative humidity from observation meteorological data and Climate Change models' output (HadCM3 and ARPEGE). Comparing the number of transitions with meteorological seasonal data allowed us to develop techniques to estimate the frequency of salt transitions based on the local climatology. Results show that it is possible to associate the Köppen-Geiger climate types with potential salt weathering. Temperate fully humid climates seem to offer the highest potential for salt damage and possible higher number of transitions in summer. Climates with dry summers tend to show a lesser frequency of transitions in summer. The analysis of temperature, precipitation and relative output from Climate Change models suggests changes in the Köppen-Geiger climate types and changes in the patterns of salt damage. For instance, West Europe areas with a fully humid climate may change to a more Mediterranean like or dry climates, and consequently the seasonality of different salt transitions. The accuracy and reliability of the projections might be improved by simultaneously running multiple climate models (ensembles). Copyright © 2011 Elsevier B.V. All rights reserved.

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...

Searching for the philosopher's stone: promising links between meditation and brain preservation.

Science.gov (United States)

Luders, Eileen; Cherbuin, Nicolas

2016-06-01

In the context of an aging population and increased prevalence of dementia and other neurodegenerative diseases, developing strategies to decrease the negative effects of aging is imperative. The scientific study of meditation as a potential tool to downregulate processes implicated in brain aging is an emerging field, and a growing body of research suggests that mindfulness practices are beneficial for cerebral resilience. Adding further evidence to this notion, an increasing number of imaging studies report effects of meditation on brain structure that are consistent with our understanding of neuroprotection. Here, we review the published findings in this field of research addressing the question of whether meditation diminishes age-related brain degeneration. Altogether, although analyses are still sparse and based on cross-sectional data, study outcomes suggest that meditation might be beneficial for brain preservation-both with respect to gray and white matter-possibly by slowing down the natural (age-related) decrease of brain tissue. Nevertheless, it should also be recognized that, until robust longitudinal data become available, there is no evidence for causation between meditation and brain preservation. This review includes a comprehensive commentary on limitations of the existing research and concludes with implications and directions for future studies. © 2016 New York Academy of Sciences.

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...

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

Design of all-weather celestial navigation system

Science.gov (United States)

Sun, Hongchi; Mu, Rongjun; Du, Huajun; Wu, Peng

2018-03-01

In order to realize autonomous navigation in the atmosphere, an all-weather celestial navigation system is designed. The research of celestial navigation system include discrimination method of comentropy and the adaptive navigation algorithm based on the P value. The discrimination method of comentropy is studied to realize the independent switching of two celestial navigation modes, starlight and radio. Finally, an adaptive filtering algorithm based on P value is proposed, which can greatly improve the disturbance rejection capability of the system. The experimental results show that the accuracy of the three axis attitude is better than 10″, and it can work all weather. In perturbation environment, the position accuracy of the integrated navigation system can be increased 20% comparing with the traditional method. It basically meets the requirements of the all-weather celestial navigation system, and it has the ability of stability, reliability, high accuracy and strong anti-interference.

Diagnosing stone decay in built heritage. Facts and perspectives

Directory of Open Access Journals (Sweden)

Lodola, Stefania

2008-06-01

Full Text Available Stone and other materials used for the construction of historic buildings, memorial statues, gravestones and similar are exposed to weathering and polluting agents and, therefore, progressive decay. Such deterioration, whether physical, chemical or biological, involves mineral phases and their interrelationships (structure and texture.A review of the analytical procedures applied in scientific research on stone damage has revealed the need for appropriate tools and tests (each with a specific scope, depending on the extant damage to identify decay processes and apply the correct “therapy”, i.e. temporary and/or permanent protection (cleaning, protection, reinforcement, repair and/or replacement. A number of case histories of famous components of the Italian built heritage are discussed in the context of the use of integrated methodologies for researching decay in different kinds of stone.La piedra y otros materiales utilizados para construir edificios históricos, estatuas conmemorativas, lápidas, etc. sufren la acción de los agentes atmosféricos y contaminantes y, por tanto, a una degradación progresiva. En dicha degradación, ya sea física, química o biológica, intervienen las fases minerales de la piedra y sus correspondientes interrelaciones (estructura y textura.Un análisis de los procedimientos analíticos aplicados en la investigación científica sobre los daños en la piedra ha puesto de manifiesto la necesidad de herramientas y pruebas adecuadas (cada una con un objetivo concreto, según el daño existente para identificar los procesos de degradación y aplicar la «terapia» adecuada; es decir, una protección provisional o definitiva (limpieza, protección, refuerzo, reparación o sustitución.Se comentan varios casos prácticos relacionados con conocidos elementos del patrimonio construido italiano en el contexto del empleo de metodologías integradas para la investigación de la degradación en distintos tipos

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...

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

Preservation of Records, Knowledge and Memory across Generations (RK and M). Markers - Reflections on Inter-generational Warnings in the Form of Japanese Tsunami Stones

International Nuclear Information System (INIS)

Pescatore, Claudio; Botezvan, Radu; Luik, Abe; Holtorf, Cornelius; Van Wyck, Peter C.

2014-01-01

As states with nuclear power programmes are, or intend to become, engaged in planning the disposal of their high-level and/or long-lived radioactive waste in deep geological repositories, means to ensure that future generations will be aware of these repositories and not disturb them are being studied. Preservation of Records, Knowledge and Memory (RK and M) across Generations, launched in March 2010, is the relevant initiative under the NEA Radioactive Waste Management Committee in this area. Its several years of work and findings are documented online at www.oecdnea. org/rwm/rkm. A strategy of communicating important information to future generations must be based on several complementary means and approaches. Markers placed in the vicinity of closed repositories represent one potential component of this strategy. The RK and M initiative's glossary defines a marker as 'a long-lasting object that indicates an area of influence, power or danger. It is placed strategically at or near the site for immediate recognition or for discovery at a later time'. Markers are meant to reach future generations in the medium (a few hundred years) to long term (hundred thousand of years) and are conceived to be immobile (that is, in permanent association with a site), robust (in order to maximize survivability on its own) and provide messages that are likely to be understandable across generations. A marking system can range from a simple stone to a contrived and monumental multi-component system. The present report seeks to develop the understanding of the potential effectiveness of makers drawing from the study of the role that stone markers played in Japan during the Tohoku tsunami event of 2011. There are hundreds such markers placed at various epochs on Japan's north-eastern coast to warn future generations about the dangers of tsunamis. The existence of markers for recurrent, destructive events may help save lives, as in the case of the villages of Murohama and Aneyoshi

"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

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

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)

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.

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

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.)

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.

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 ...

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.

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...

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....

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.

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.

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.

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.

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

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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

Extracorporeal Shockwave Lithotripsy of Primary Intrahepatic Stones

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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

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)

Effectiveness of Treatment Modalities on Kidney Stone Recurrence.

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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.

Efficacy of the lithotripsy in treating lower pole renal stones.

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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.

Can Hounsfield Unit Value Predict Type of Urinary Stones?

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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

Kidney Stones in Children and Teens

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... 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 ...

The Guy's stone score--grading the complexity of percutaneous nephrolithotomy procedures.

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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.

Atmospheric Weathering of Historic Monuments and Their Related Conservation Issues

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Caner-Saltık Emine N.

2018-01-01

Full Text Available Atmospheric environment affects the materials of historic monuments and their structure starting from the time of their construction. Daily and seasonal changes in temperature and humidity, wind, snow and rainfall, soluble salts carried by water, biological agents, pollutant gases and particulate matter are some of the agents in atmospheric environment that introduce weathering by physical, chemical and biological processes in the materials of the monuments such as natural building stones, bricks, mortars and plasters, mud brick etc. The weathering processes need to be well diagnosed by identification of main mechanisms of decay and major responsible agents, degree and depth of deterioration expressed with measurable parameters of physical, physicomechanical properties, and micro structural changes together with their distribution on the monument. Success of conservation treatments strongly depend on those diagnostic studies and compatibility of the treatments with the deteriorated and relatively sound parts of the historic materials. Current approach to materials conservation is to be able to make minimum intervention to historic material by targeting the conservation treatment to the deteriorated area for the purpose of controlling the deterioration factors and achieving compatible and durable conservation of historical material. In this presentation, two examples of diagnostic research and conservation treatments based on and guided by the diagnostic results are summarized concerning historic stone monuments exposed to atmospheric environment since more than two thousand years. The first example is on the marble walls of Temple of Augustus in Ankara exposed to polluted urban atmosphere. The second example is on the limestone statues of Nemrut Mount Monument in Adıyaman-Turkey, exposed to rural atmosphere with harsh climatic conditions. Finally, a brief discussion on current research issues related to historic materials conservation in

Protection by polyphenol extract from olive stones against apoptosis produced by oxidative stress in human neuroblastoma cells

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Cortés-Castell, Ernesto; Veciana-Galindo, Carmen; Torró-Montell, Luis; Palazón-Bru, Antonio; Sirvent-Segura, Elia; Gil-Guillén, Vicente; Rizo-Baeza, Mercedes

2016-02-16

We evaluated the protective activity of an extract from a by-product such as olive stones, through its ability to inhibit H202 induced apoptosis in the SH-SY5Y human neuroblastoma cell line. To such end, 20,000 cells/well were cultivated and differentiation with retinoic acid was initiated. Once the cells were differentiated, apoptosis was induced with and without H2O2 extract. Finally, cDNA extraction was performed, and pro-apoptotic genes Bax and anti-apoptotic genes Bcl-2 were analyzed. Quantification of the gene expression was performed using the GAPDH gene marker. Cell viability with the extract is 97.6% (SD 5.7) with 10 mg/l and 62.8% (SD 1.2) to 50 mg/l, using 10 mg/l for the biomarker assay. The retinoic acid differentiated SH-S cell line (10 μM) shows a clear apoptosis when treated with H2O2 150 μM, with a Bax/Bcl-2 ratio of 3.75 (SD 0.80) in contrast to the differentiated control cells subjected to H2O2 and with extract, which have the same ratio of 1.02 (SD 0.01-0.03). The olive stone extract shows anti-apoptotic activity in the provoked cell death of SH-SY5Y human neuroblastoma cells in their normal state, defending them from oxidative stress which produces a significant increase in the apoptotic gene ratio in contrast to anti-apoptotic genes (Bax/Bcl-2).

Evidence Report: Risk of Renal Stone Formation

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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.

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

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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.

Famous Stone Patients and Their Disease

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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.

Retroperitoneoscopy for treatment of renal and ureteral stones.

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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.

Retroperitoneoscopy for treatment of renal and ureteral stones

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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.

INCREASING DEMANDS FOR NATURAL STONES USAGE AROUND THE WORLD

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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

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, ...

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)

Accuracy of endoscopic intraoperative assessment of urologic stone size.

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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.

Imaging-based logics for ornamental stone quality chart definition

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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.

Soft-Bodied Fossils Are Not Simply Rotten Carcasses - Toward a Holistic Understanding of Exceptional Fossil Preservation: Exceptional Fossil Preservation Is Complex and Involves the Interplay of Numerous Biological and Geological Processes.

Science.gov (United States)

Parry, Luke A; Smithwick, Fiann; Nordén, Klara K; Saitta, Evan T; Lozano-Fernandez, Jesus; Tanner, Alastair R; Caron, Jean-Bernard; Edgecombe, Gregory D; Briggs, Derek E G; Vinther, Jakob

2018-01-01

Exceptionally preserved fossils are the product of complex interplays of biological and geological processes including burial, autolysis and microbial decay, authigenic mineralization, diagenesis, metamorphism, and finally weathering and exhumation. Determining which tissues are preserved and how biases affect their preservation pathways is important for interpreting fossils in phylogenetic, ecological, and evolutionary frameworks. Although laboratory decay experiments reveal important aspects of fossilization, applying the results directly to the interpretation of exceptionally preserved fossils may overlook the impact of other key processes that remove or preserve morphological information. Investigations of fossils preserving non-biomineralized tissues suggest that certain structures that are decay resistant (e.g., the notochord) are rarely preserved (even where carbonaceous components survive), and decay-prone structures (e.g., nervous systems) can fossilize, albeit rarely. As we review here, decay resistance is an imperfect indicator of fossilization potential, and a suite of biological and geological processes account for the features preserved in exceptional fossils. © 2017 The Authors. BioEssays Published by WILEY Periodicals, Inc.

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

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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.

Features and Formation Causes of Granitic Stone Forest in Bayan Nur, Inner Mongolia%内蒙古巴彦淖尔花岗岩石林的特征及成因

Institute of Scientific and Technical Information of China (English)

王璐琳; 武法东

2014-01-01

通过对内蒙古巴彦淖尔花岗岩石林的调查和研究,对其形态类型和成因作了详尽的阐述.研究区的花岗岩石林从形态上可分为石柱、石锥、石蛋、蘑菇石、石排5种类型.根据形态特征的分析,该石林是由晚古生代花岗闪长岩—黑云二长花岗岩经重力崩塌、风化、流水侵蚀等外力作用而形成的一种特殊地貌,其形成发育受岩性、地质构造、气候条件等因素的控制.%Based on the field investigation on the granitic stone forest in Bayan Nur,Inner Mongolia,in this paper the features and formation causes of the granitic stone forest were discussed in detail.The granitic stone forest was divided into five types,i.e.the stalagnate,talus cone,stone egg,mushroom stone and stone row.According to the morphologic features of the granitic stone forest,it was considered that the stone forest is a kind of special landform and formed from the Late Paleozoic granodiorite-biotite monzonitic granite under the effect of external forces,such as gravitational collapse,weathering,water erosion and wind erosion.The formation and development of the stone forest are affected by lithology,geological structure,climate conditions,etc.

Development of a laboratory model of a phototroph-heterotroph mixed-species biofilm at the stone/air interface

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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.

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.

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.

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.

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

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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.

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.

Analysing deterioration of marble stones exposed to underwater conditions

Science.gov (United States)

Cámara, Beatriz; Álvarez de Buergo, Mónica; Bethencourt, Manuel; Freire-Lista, David; Fort, Rafael

2016-04-01

, provides useful information for evaluation of the deterioration processes of heritage stones in a marine environment, and for conservation measures aimed at the in situ preservation of archaeological sites. Acknowledgements: Community of Madrid for financing Geomateriales2 program (P2013/MIT2914), CEI-Moncloa UCM-UPM, Applied Petrology for Heritage Stone Materials Conservation Research Group.

Effect of Ferrous Additives on Magnesia Stone Hydration

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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.

Pancreatic Stones: Treat or Ignore?

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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.

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.

Strength Improvement of Clay Soil by Using Stone Powder

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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.

Study of frontal weather system using satellite images

International Nuclear Information System (INIS)

Qureshi, J.; Ershad, S.

2005-01-01

Pakistan which is situated in the south Asian sub continent, has a peculiar climatological position. It is one of the few countries in the world, which undergo a complete transformation from summer to winter season. However this project only pertains to the winter weather conditions in Pakistan. During winter, the land masses cool off rapidly as compared to the seas and so high pressure cells are developed over land causing, weak anti-cyclonic circulation over the country. In between these cells of anti-cyclonic flow of wind, there are zones of convergence, which offer a good breeding place for low-pressure waves. The low-pressure waves are similar to the extra tropical depressions and approach and approach Pakistan from west. From the same reason these are locally called the western Disturbances. Consequently the focus of study is on the extra tropical cyclones which originate along the boundary between polar continental and tropical or polar maritime and tropical maritime air masses. The extra tropical cyclones (also called western disturbances and westerly waves.) which are embedded in westerly flow of air move across north of Pakistan are usually originate from the Mediterranean sea. These systems consist of two types of fronts i.e. warm and cold fronts. In fact these systems can be traced right from the Atlantic Ocean and Mediterranean Sea. The location of frontal weather is generally associated with the surrounding synoptic situation, geographical position of the westerly wave, location of subtropical jet stream, steering wind level etc. although the satellite imageries are quite helpful for forecasting the frontal weather over our region however the weather charts (both surface and upper air ) and jet maps are also very helpful for this purpose

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".

Effectiveness of stone treatments in enhancing the durability of bioclastic calcarenite in (Granada, Spain

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Sebastián, E.

2008-12-01

Full Text Available Santa Pudia limestone, a biocalcarenite highly sensitive to decay, is one of the most commonly used building materials in historical monuments in the city of Granada, Spain. The compatibility between a variety of stone treatments (consolidants and/or water repellents and this calcarenite was analyzed and the resulting improvement in durability assessed. To this end, a two-stage accelerated ageing process was implemented. In the first, freshly quarried, undamaged specimens were altered to resemble the weathered stone in buildings. The second was conducted after applying the various treatments to the artificially aged stone to test their effectiveness. While all the treatments studied (Tegosivin HL100, Silo 111, Estel 1100 and Tegovakon V enhanced stone resistance to decay while barely affecting chromatic parameters, the most effective was Tegowakon V, as it provided the best results in the hydric tests on the limestone.La calcarenita de Santa Pudia es uno de los materiales rocosos de construcción más empleados en las edificaciones monumentales de la ciudad de Granada (España. Se ha evaluado la compatibilidad de diversos productos de tratamiento (de consolidación y/o hidrofugación con esta calcarenita y como son capaces de mejorar su durabilidad. Para ello, se han realizado dos fases de envejecimiento acelerado: la primera tenía el objetivo de acercar el material de cantera sin alterar (“sano” a las condiciones reales del material puesto en obra y actualmente deteriorado; la segunda, efectuada después de aplicar los tratamientos sobre la calcarenita deteriorada, con el fin de determinar su grado de eficacia. Se ha podido comprobar que aunque, en general, todos los productos de tratamiento seleccionados (Tegosivin HL100, Silo 111, Estel 1100 y Tegovakon V mejoran las propiedades del material frente al deterioro y apenas modifican sus parámetros cromáticos, el más eficaz es el Tegovakon V ya que es el que proporciona mejores resultados

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.

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...

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.

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…

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...

EVALUATION OF CONSISTENCY AND SETTING TIME OF IRANIAN DENTAL STONES

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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.

[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.

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.

Assessment of exposure to hand-arm vibration and its related health effects in workers employed in stone cutting workshops of Hamadan city

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Roya Bayat

2016-06-01

Full Text Available Introduction: The workers employed in stone cutting workplace are exposed to hand-arm vibration and its complications. The aim of this study was to evaluate the exposure to hand-arm vibration and its health effects on workers in the stone cutting workshops. Methods: In this descriptive-analytic study, 40 workers of Hamadan city stone cutting who worked with stone cutting machines were examined. Measuring exposure to hand-arm vibration was performed by standard methods ISO 5349. Symptoms related hand-arm vibration syndrome using a questionnaire construction was studied. Data were analyzed using SPSS software. Results: Results showed that 8-hour equivalent acceleration of hand-arm vibration exposure in stonecuttingworkers was exceeds the permissible exposure levels of country (Pv<0.05. Most average hand and arm vibration acceleration was measured in the Z axis. The average vibration acceleration hand-arm and cutting transverse and longitudinal cutting significant difference was observed (Pv<0.05. Conclusion: In regard to exposure level of stone cutting workers compared with the national exposure limit, the training of health care, non-smoking, and use of anti-vibration gloves, work rotations canthe effective in reducing the risk of health effects. Furthermore, it seems essential to track the health effects associated with human vibration by use of screening tests in the work place seem.

Infrared and ultraviolet laser removal of crustose lichens on dolomite heritage stone

Energy Technology Data Exchange (ETDEWEB)

Sanz, Mikel; Oujja, Mohamed [Instituto de Química Física Rocasolano (IQFR), CSIC, Serrano 119, 28006 Madrid (Spain); Ascaso, Carmen; Ríos, Asunción de los; Pérez-Ortega, Sergio [Museo Nacional de Ciencia Naturales (MNCN), CSIC, Serrano 115 bis, 28006 Madrid (Spain); Souza-Egipsy, Virginia [Instituto de Ciencias Agrarias (ICA), CSIC, Serrano 115 bis, 28006 Madrid (Spain); Wierzchos, Jacek; Speranza, Mariela [Museo Nacional de Ciencia Naturales (MNCN), CSIC, Serrano 115 bis, 28006 Madrid (Spain); Cañamares, Maria Vega [Instituto de Estructura de la Materia (ICEM), CSIC, Serrano 121, 28006 Madrid (Spain); Castillejo, Marta, E-mail: marta.castillejo@iqfr.csic.es [Instituto de Química Física Rocasolano (IQFR), CSIC, Serrano 119, 28006 Madrid (Spain)

2015-08-15

Graphical abstract: - Highlights: • Laser irradiation at 1064 nm (IR) or 355 nm (UV) partially removes epilithic lichens on dolostone. • Irradiation in a sequential, dual IR–UV mode efficiently eliminates lichen thalli. • Dual IR–UV irradiation mode induces severe damage on endolithic colonizers of dolostone. - Abstract: Laser removal of biodeteriogen layers warrants detailed studies due to the advantages it brings with respect to mechanical elimination or the use of biocides. We have investigated elimination of biological crusts on dolomite stones from heritage sites in central Spain. The samples were colonized by epilithic crustose lichens of different species, such as Caloplaca sp. and Verrucaria nigrescens. A comparative study was carried out by applying infrared (1064 nm) and ultraviolet (355 nm) nanosecond laser pulses and sequences pulses of the two wavelengths using a Q-switched Nd:YAG system. To detect anatomical and ultrastructural damage to the lichens, and to assess possible morphological and chemical changes on the underlying stone induced by laser irradiation, we used stereomicroscopy, scanning electron microscopy with backscattered electron imaging and Fourier transform Raman spectroscopy. The optimal conditions for removal of the colonization crust, while ensuring preservation of the lithic substrate, were obtained for dual infrared-ultraviolet sequential irradiation.

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.

[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.

Crushed Stone Operations

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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...

Approach to Residual Kidney Stone Fragments After Shock Wave Therapy

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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.

The Climate and its Impacts on deterioration and weathering rate of EI-Nadura Temple in El- Kharga Oasis, Western Desert of Egypt.

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Ismael, Hossam

2015-04-01

Undoubtedly, El-Kharga Oasis monumental sites are considered an important part of our world's cultural heritage in the South Western Desert of Egypt. These sites are scattered on the floor of the oasis representing ancient civilizations. The Roman stone monuments in Kharga represent cultural heritage of an outstanding universal value. Such those monuments have suffered weathering deterioration. There are various elements which affect the weathering process of stone monuments: climate conditions, shapes of cultural heritages, exposed time periods, terrains, and vegetation around them, etc. Among these, climate conditions are the most significant factor affecting the deterioration of Archeological sites in Egypt. El- Kharga Oasis belongs administratively to the New Valley Governorate. It is located in the southern part of the western desert of Egypt, lies between latitudes 22°30'14" and 26°00'00" N, and between 30°27'00" and 30°47'00" E. The area of El Kharga Oasis covers about 7500 square kilometers. Pilot studies were carried out on the EI-Nadura Temple, composed of sandstones originating from the great sand sea. The major objective of this study is to monitor and measure the weathering features and the weathering rate affecting the building stones forming El-Nadora Roman building rocks in cubic cm. To achieve these aims, the present study used analysis of climatic data such as annual and seasonal solar radiation, Monthly average number of hours of sunshine, maximum and minimum air temperatures, wind speed, which have obtained from actual field measurements and data Meteorological Authority of El-Kharga station for the period 1977 to 2010 (33 years), and from the period 1941-2050 (110 years) as a long term of temperature data. Several samples were collected and examined by polarizing microscopy (PLM), X-ray diffraction analysis (XRD) and scanning electron microscopy equipped with an energy dispersive X-ray analysis system (SEM-EDX). The results were in

Factors affecting lower calyceal stone clearance after Extracorporeal shock wave lithotripsy

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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.

Abdominal colic due to ureteric diverticulum with stone formation

International Nuclear Information System (INIS)

Roodhooft, A.M.; Boven, K.; Acker, K.J. van; Gentens, P.

1987-01-01

In a 15-year-old boy right lower abdominal colicky pain was caused by intermittent obstruction of the ureter by stones which had accumulated in a ureteric diverticulum. As was shown by repeated X-rays, each of these stones had moved to the ureter and back to the diverticulum. Ureteric diverticulum mostly remains asymptomatic in children: stone formation and obstruction of the ureter by the stones is one of the instances which may cause symptoms. (orig.)

Analysis of urinary stone constituents using powder X-ray diffraction ...

Indian Academy of Sciences (India)

WINTEC

drug and bacteria induced factors are all external factors causing urinary stones. ... gion of hot climate, low rain fall, and increased salin- ity of ground water, is a ... Gender the patient stones the stones habit and age. Stone removal procedure. KSHP. 1. KSHP1 Vegetarian. Male, 50. Natural excretion in the urine. KSHIM. 1.

Renal geology (quantitative renal stone analysis) by 'Fourier transform infrared spectroscopy'.

Science.gov (United States)

Singh, Iqbal

2008-01-01

To prospectively determine the precise stone composition (quantitative analysis) by using infrared spectroscopy in patients with urinary stone disease presenting to our clinic. To determine an ideal method for stone analysis suitable for use in a clinical setting. After routine and a detailed metabolic workup of all patients of urolithiasis, stone samples of 50 patients of urolithiasis satisfying the entry criteria were subjected to the Fourier transform infrared spectroscopic analysis after adequate sample homogenization at a single testing center. Calcium oxalate monohydrate and dihydrate stone mixture was most commonly encountered in 35 (71%) followed by calcium phosphate, carbonate apatite, magnesium ammonium hexahydrate and xanthine stones. Fourier transform infrared spectroscopy allows an accurate, reliable quantitative method of stone analysis. It also helps in maintaining a computerized large reference library. Knowledge of precise stone composition may allow the institution of appropriate prophylactic therapy despite the absence of any detectable metabolic abnormalities. This may prevent and or delay stone recurrence.

[Factors affecting residual stones after percutaneous nephrolithotomy in patients with renal calculus].

Science.gov (United States)

Qiao, Mingzhou; Zhang, Haifang; Zhou, Chenlong

2015-11-24

To explore the factors affecting the residual stones after percutaneous nephrolithotomy (PCNL) in patients with renal calculus. A retrospective analysis was performed for 1 200 patients who were affected by renal calculus and treated with PCNL between Jan 2008 and May 2014 in People's Hospital of Anyang City. Among those patients, 16 were diagnosed as bilateral renal stone and had two successive operations. The size, location and number of stones, previous history of surgery, the degree of hydronephrosis, urinary infection were included in the univariate analysis. Significant factors in univariate analysis were included in the multivariate analysis to determine factors affecting stone residual. A total of 385 cases developed stone residual after surgery. The overall residual rate was 31.7%. In univariate analysis, renal pelvis combined with caliceal calculus (P=0.006), stone size larger than 4 cm (P=0.005), stone number more than 4 (P=0.002), the amount of bleeding more than 200 ml (P=0.025), operation time longer than 120 minutes (P=0.028) were associated with an increased rate of stone residual. When subjected to the Cox multivariate analysis, the independent risk factors for residual stones were renal pelvis combined with caliceal calculus (P=0.049), stone size larger than 4 cm (P=0.038) and stone number more than 4 (P=0.018). Factors affecting the incidence of residual stones after PCNL are the size, location and number of stones. Larger size stone and the presence of renal pelvis combined with caliceal calculus are significantly associated with residual stones. Nevertheless, stone number less than 4 indicates an increased stone clearance rate.

The preservation of green goat skin using liquid smoke from coconut shell

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Suliestiyah Wiryodiningrat

2009-07-01

Full Text Available The objective of the research on the presentation of green goat skin using liquid smoke was to reduce the environmental contamination caused by usage of the environmentally-unfriendly chemical in skin preservation process. Liquid smoke is the outcome of coconut shell waste containing a lot of phenol and acid compound. It is an organic material that is environment-friendly and it can inhibit the bacteria growth. The research was conducted using 18 pieces of green goat skin. Eighteen pieces of green goat skin were divided into 2 treatments. The first stage treatment used liquid smoke as the preserving material with 0,1%, 0,5%, and 1,0 % in concentrations without crystal salt and anti-bacterial material. The second stage treatment used liquid smoke with 5%, 10% and 15% in concentrations and used crystal salt without anti-bacteria material. The skins then were stretched and dried in the sun. They were observed for 1 week, 2 weeks and 1 month. The results of the skin preservation then were tested in organoleptic method, including the tests for the shedding of feather and the damage of skin owing to bacteria / louse. The skins also were tested in physical method (tensile strength & elongation at break. The result of search showed that the skins preservation for month using liquid smoke, 10% in concentration, was the most effective, Usage of liquid smoke as the substitute of anti-bacteria/fungicide would reduce a part of the environmental contamination owing to usage of the environment-unfriendly chemical in skin preservation process.

Laparoscopic transperitoneal ureterolithotomy for large ureteric stones

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Ahmed Al-Sayyad

2012-01-01

Conclusion: Laparoscopic transperitoneal ureterolithotomy is a safe and effective approach for selected patients with large proximal ureteric stones with reduced postoperative pain and short hospital stay, and should be considered as a treatment option for such stones.

[Ultraminipercutaneous nephrolithotripsy in treating kidney stones].

Science.gov (United States)

Martov, A G; Dutov, S V; Andronov, A S

2016-04-01

Percutaneous nephrolithotripsy (PNL) is the recommended method of surgical treatment of kidney stones of size greater than 2 cm. Trends in the development of modern urology have been steadily toward less traumatic method to treat nephrolithiasis - minimally invasive PNL. The present work aimed to explore of the possibilities of one of the modern variants of minimally invasive PNL - ultra-mini-PNL in treating nephrolithiasis. The study included 60 patients (mean age 45.6+/-7.2 years) with isolated kidney calculus, up to 2.0 cm or several stones with a total size of up to 2.5 cm. All patients were found to have 77 kidney stones, six of which had a size of 10 mm, 51 had a size of 11-15 mm and 20 had a size of 16-20 mm. 45% of patients had isolated renal pelvic stones and 28.3% had stones in the renal pelvis and lower calyx. All patients underwent ultra-mini-PNL using nephroscope size 7.5 Ch and tube size 12 Fr. The average duration of surgery from the moment of the puncture of the pyelocaliceal system to installing the nephrostomy tube was 65.4 minutes. Complete clearance of stones after single-stage ultra-mini-PNL was observed in 80% of cases. Nephrostomy tube was removed on days 2-3. The average postoperative hospital stay was 5.1 days. The most common complication was postoperative exacerbation of pyelonephritis (13.3% of patients), successfully treated with conservative measures. There were no cases of postoperative bleeding, accompanied by anemia and needed a blood transfusion. Considering high effectiveness and low rate of complications of ultra-mini-PNL, it can be successfully used in treating nephrolithiasis among a wide group of patients.

Weather derivatives: Business hedge instrument from weather risks

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Đorđević Bojan S.

2014-01-01

Full Text Available In the late 1990s, a new financial market was developed - a market for weather derivatives, so that the risk managers could hedge their exposure to weather risk. After a rather slow start, the weather derivatives market had started to grow rapidly. Risk managers could no longer blame poor financial results on the weather. Weather risk could now be removed by hedging procedure. This paper will explain briefly what the weather derivatives are and will point out at some of the motives for use of derivatives. Thereafter we will look at the history of the weather risk market, how the weather derivatives market has developed in recent years and also who are the current and potential players in the weather derivatives market.

31 CFR 103.140 - Anti-money laundering programs for dealers in precious metals, precious stones, or jewels.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Anti-money laundering programs for... FOREIGN TRANSACTIONS Anti-Money Laundering Programs Anti-Money Laundering Programs § 103.140 Anti-money...) Anti-money laundering program requirement. (1) Each dealer shall develop and implement a written anti...

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.

Early cretaceous Obernirchen and Bentheim sandstones from Germany used as dimension stone in the Netherlands: geology physical properties, architectural use and comparative weathering

NARCIS (Netherlands)

Dubelaar, C.W.; Nijland, T.G.

2015-01-01

The Netherlands, with only scarce occurrences of outcropping or shallow buried natural stone, has over centuries imported huge quantities of Early Cretaceous Bentheim Sandstone and Obernkirchen Sandstone from Germany. The present paper provides an overview of their distribution and properties

Clinical effect of anatomical hepatectomy in treatment of intrahepatic bile duct stones

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WANG Dianbei

2017-01-01

TBil than the irregular hepatectomy group (AST: 62.7±25.4 U/L vs 114.8±37.0 U/L, t=9.024, P＜0.01; ALT: 91.3±35.7 U/L vs 149.5±53.3 U/L, t=7.067, P＜0.01; TBil: 31.8±10.4 μmol/L vs 51.3±14.3 μmol/L, t=8.531, P＜0.01. ConclusionUnder the premise of preserving the function of the residual liver, anatomical hepatectomy can completely remove the lesions and has the features of low residual stone rate, low recurrence rate and rapid postoperative recovery. It has a better clinical effect than irregular hepatectomy.

The stones and historic mortars of the Santissima Trinità di Saccargia Romanesque Basilica (Sardinia, Italy): a multi-analytical techniques' approach for the study of their features and provenance

Science.gov (United States)

Columbu, Stefano; Palomba, Marcella; Sitzia, Fabio

2015-04-01

A research project devoted to the study of building materials of the Romanesque churches in Sardinia is currently underway. One of the objectives of the project is to focus the mineral, chemical-physical and petrographic characterisation of the construction materials, as well as the alteration processes. To make a contribution to the preservation of Sardinian monuments, we suggests a new approach to define the different alteration-modes of rocks in function of their local exposure to the weather, studying: 1) the changes of physical properties on surface of stone (porosity, water absorption, micro-morphology) determined through laboratory tests and photogrammetry observations, 2) the alteration phases present on surface (e.g., secondary minerals, soluble salts) determined by mineralogical and chemical investigations. This methodological approach will allow to select appropriate, suitable and compatible materials for replacing the original altered one's, and to plan appropriate strategies devoted to the restoration work. In this paper the geomaterials used for construct the Santissima Trinità di Saccargia Basilica have been investigated. The church, finished in 1116 over the ruins of a pre-existing monastery, is the most important Romanesque site in the island. Have been studied the chemical alterations and physical decay of two different stones, as volcanic rocks (i.e., basalt) and sedimentary rocks (i.e., limestones) used in bichromy on the Basilica. The main purpose is to observe the different modes of alteration of these two lithologies with different petrophysical characteristics, placed in the same conditions of weathering. Macroscopic evidences show that the limestones, while not having a high porosity, they were strongly affected by alteration phenomena, especially in the outer surface of ashlars, due to the solubilization of the carbonate matrix. The basalt rocks show no obvious physical alteration. Occasionally, in some ashlar located in basal zone of the

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...

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.

Sculpture: Stone Shapes, Art: 6683.08.

Science.gov (United States)

Dubocq, Edward R.

This elective course for grades 7-12 was created with a three fold purpose: 1) to create in the student an awareness of the effect of sculptural forms on his environment; 2) to introduce the student to an appreciation of stone sculpture; and 3) to further enhance the artistic abilities of the student through sculpting in stone. Course content…

GOES-R Space Weather Data: Achieving User Ready Products

Science.gov (United States)

Rowland, W. F.; Tilton, M.; Redmon, R. J.; Goodman, S. J.; Comerford, M.

2017-12-01

Forecasters and the science community will rely on improved Space Weather products from the next generation of Geostationary Operational Environmental Satellite (GOES-R Series) for decades to come. Many issues must be successfully addressed in order to produce useful products. The instruments themselves and their basic scientific measurements (Level 1b data, i.e. L1b) must be calibrated and validated. Algorithms must be created to transform L1b into the specific environmental parameters that are of interest to forecasters and the community (Level 2+, i.e. L2+). In the case of Space Weather data, because the L2+ products are not generated within the core GOES-R Ground Segment, a separate system had to be developed in order to implement the L2+ products. Finally, the products must be made available to real time and retrospective users, as well as preserved for future generations. We give an overview of the path to production of the GOES-R Space Weather products, and the role of the National Centers for Environmental Information (NCEI) in this process.

Stone coalgebras

NARCIS (Netherlands)

C.A. Kupke (Clemens); A. Kurz (Alexander); Y. Venema

2003-01-01

textabstractIn this paper we argue that the category of Stone spaces forms an interesting base category for coalgebras, in particular, if one considers the Vietoris functor as an analogue to the power set functor on the category of sets. We prove that the so-called descriptive general frames, which

Stones used in Milan architecture

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Folli, Luisa

2008-06-01

Full Text Available The city of Milan lies in a plain with clayey soil well suited to brick-making, but no stone deposits. An ample supply of stone is available, however, in the surrounding hills and mountains, which are connected to the city via both natural and artificial waterways. The types of stone used since Roman times include: granite, marble and gneiss from Ossola Valley; dolomite from Lake Maggiore; detrital limestone from Ceresio Valley; sandstone from the Brianza Hills; black limestone and marble from Lake Como; and conglomerate and sandstone from the Adda River basin. Traditionally, the chief uses have been dimension stone (all stones, column shafts (granite, slabs (marble, moulding (dolomite, limestone and ornamental (marble, dolomite, limestone.La ciudad de Milán se encuentra en una llanura de suelo arcilloso adecuado para la fabricación de ladrillos pero en la cual no hay yacimientos de rocas. No obstante, en las colinas y montañas circundantes, que están comunicadas con la ciudad mediante vías navegables naturales y artificiales, sí existe una abundante cantidad de piedra. Entre los tipos de piedra utilizados desde la época de los romanos se encuentran granitos, mármoles y gneises del valle de Ossola, dolomías del lago Mayor, calizas detríticas del valle de Ceresio (Lugano, areniscas de las colinas de la Brianza, calizas negras y mármoles del lago Como y conglomerados y areniscas de la cuenca del río Adda. Tradicionalmente, los principales usos han sido la piedra de fábrica (todas ellas, fustes de columnas (granito, losas (mármol, molduras (dolomía, caliza y ornamental (mármol, dolomía, caliza.

Radon in houses utilizing stone magazines for heat accumulation

International Nuclear Information System (INIS)

Stranden, E.

1981-01-01

Measurements of 222 Rn and its daughters in three solar energy houses utilizing stone magazines for heat accumulation are reported. Theoretical calculations of the radon contribution from the stone magazines seem to be in good agreement with the measured values. The survey indicated that this method for heat accumulation could give a significant increase in the indoor radon concentration if the radium concentration of the stone material is high. The theoretical considerations suggest that a radium concentration of 1 pCi/g of the stone material could give an increment of the radon concentration in the indoor air of about 1 pCi/l. during the heating season in a house with air volume of 250 m 3 and a 10 5 -kg stone magazine. (author)

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).

Nanobacteria: An Infectious Cause for Salivary Stone Formation and Recurrence

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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.

Data Package for Secondary Waste Form Down-Selection-Cast Stone

International Nuclear Information System (INIS)

Serne, R. Jeffrey; Westsik, Joseph H.

2011-01-01

Available literature on Cast Stone and Saltstone was reviewed with an emphasis on determining how Cast Stone and related grout waste forms performed in relationship to various criteria that will be used to decide whether a specific type of waste form meets acceptance criteria for disposal in the Integrated Disposal Facility (IDF) at Hanford. After the critical review of the Cast Stone/Saltstone literature, we conclude that Cast Stone is a good candidate waste form for further consideration. Cast stone meets the target IDF acceptance criteria for compressive strength, no free liquids, TCLP leachate are below the UTS permissible concentrations and leach rates for Na and Tc-99 are suiteably low. The cost of starting ingredients and equipment necessary to generate Cast Stone waste forms with secondary waste streams are low and the Cast Stone dry blend formulation can be tailored to accommodate variations in liquid waste stream compositions. The database for Cast Stone short-term performance is quite extensive compared to the other three candidate waste solidification processes. The solidification of liquid wastes in Cast Stone is a mature process in comparison to the other three candidates. Successful production of Cast Stone or Saltstone has been demonstrated from lab-scale monoliths with volumes of cm3 through m3 sized blocks to 210-liter sized drums all the way to the large pours into vaults at Savannah River. To date over 9 million gallons of low activity liquid waste has been solidified and disposed in concrete vaults at Savannah River.

Data Package for Secondary Waste Form Down-Selection—Cast Stone

Energy Technology Data Exchange (ETDEWEB)

Serne, R. Jeffrey; Westsik, Joseph H.

2011-09-05

Available literature on Cast Stone and Saltstone was reviewed with an emphasis on determining how Cast Stone and related grout waste forms performed in relationship to various criteria that will be used to decide whether a specific type of waste form meets acceptance criteria for disposal in the Integrated Disposal Facility (IDF) at Hanford. After the critical review of the Cast Stone/Saltstone literature, we conclude that Cast Stone is a good candidate waste form for further consideration. Cast stone meets the target IDF acceptance criteria for compressive strength, no free liquids, TCLP leachate are below the UTS permissible concentrations and leach rates for Na and Tc-99 are suiteably low. The cost of starting ingredients and equipment necessary to generate Cast Stone waste forms with secondary waste streams are low and the Cast Stone dry blend formulation can be tailored to accommodate variations in liquid waste stream compositions. The database for Cast Stone short-term performance is quite extensive compared to the other three candidate waste solidification processes. The solidification of liquid wastes in Cast Stone is a mature process in comparison to the other three candidates. Successful production of Cast Stone or Saltstone has been demonstrated from lab-scale monoliths with volumes of cm3 through m3 sized blocks to 210-liter sized drums all the way to the large pours into vaults at Savannah River. To date over 9 million gallons of low activity liquid waste has been solidified and disposed in concrete vaults at Savannah River.

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.

Stone Formation in the Infected Pediatric Enterocystoplasty

NARCIS (Netherlands)

R.B. Mathoera (Rejiv)

2003-01-01

markdownabstract__Abstract__ Proteus mirabilis is one of the most frequent bacterial agents that can induce infection stone formation by urease production. In recent years the influence of Proteus mirabilis on stone formation in enterocystoplasties has been primarily related to the presence of

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...

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...

Moisture distribution in the stone portal of a church: how it influences the salt accumulation in porous limestone

Science.gov (United States)

Török, Ákos; Galambos, Éva

2017-04-01

Mathias Church of Budapest (Hungary) is an emblematic stone monument that represents various phases of constructions from Medieval period to the early 20th century. The church is found at the elevated Castle Hill and forms a landmark at the UNESCO World Heritage Site of Budapest. Its main construction material is porous Miocene limestone. Besides porous limestone travertine was also extensively used. The current study focuses on the Medieval Gate of the church which encompasses richly decorated porous limestone ornaments. The gate is now sheltered and form an interior portal of the church. It shows various forms of stone decay. The most striking one is efflorescence of salts. This feature has become more intense in the past years leading to flaking and granular disintegration of the limestone, causing damage to the monument. This study focuses on the detection of moisture content within the stone structure and its role in the salt accumulation. To obtain this goal in situ moisture measurements were made along vertical profiles by a portable moisture detector (Gann-Hydromette). It allowed outlining the moisture distribution within the studied structure. The moisture measurement was combined with sampling of salt efflorescence and porous limestone of the gate, itself. The samples were tested by optical microscopy. Conductivity, salt content and main elements were also detected from solutions. Mineralogical composition was recorded by XRD and Thermogravimetric analyses. Magnesium-sulphates were found to be the main salts responsible for damages. Besides sulphates chlorides were also detected. Gypsum was also found in the weathering crusts of the previously exposed limestone surfaces. It accumulated in black crusts but was also detected in white efflorescence and below the stone surface. The salt distribution clearly correlates with the moisture content. The financial support of NKFI Fund (ref. no. K 116532) is appreciated.

Interpreting Stone's model of Berry phases

International Nuclear Information System (INIS)

Carra, Paolo

2004-01-01

We show that a simple quantum-mechanical model, put forward by Stone some time ago, affords a description of site magnetoelectricity, a phenomenon which takes place in crystals (and molecular systems) when space inversion is locally broken and coexistence of electric and magnetic moments is permitted by the site point group. We demonstrate this by identifying a local order parameter, which is odd under both space inversion and time reversal. This order parameter (a magnetic quadrupole) characterizes Stone's ground state. Our results indicate that the model, extended to a lattice of sites, could be relevant to the study of electronic properties of transition-metal oxides. A generalization of Stone's Hamiltonian to cover cases of different symmetry is also discussed. (letter to the editor)

Risk Factors for Recurrence of Symptomatic Common Bile Duct Stones after Cholecystectomy

Directory of Open Access Journals (Sweden)

Ju Hyun Oak

2012-01-01

Full Text Available Purpose. The recurrence of CBD stone is still observed in a considerable number of patients. The study was to evaluate the risk factors for recurrence of symptomatic CBD stone in patients who underwent cholecystectomy after the removal of CBD stone. Methods. The medical records of patients who underwent removal of CBD stone with subsequent cholecystectomy were reviewed. The risk factors for the recurrence of symptomatic CBD stone were compared between the recurrence and the nonrecurrence group. Results. The mean follow-up period was 40.6 months. The recurrence of symptomatic CBD stones was defined as the detection of bile duct stones no sooner than 6 months after complete clearance of CBD stones, based on symptoms or signs of biliary complication. 144 patients (68 males, 47.2% were finally enrolled and their mean age was 59.8 (range: 26~86 years. The recurrence of CBD stone occurred in 15 patients (10.4%. The mean period until first recurrence was 25.9 months. The presence of type 1 or 2 periampullary diverticulum and multiple CBD stones were the independent risk factors. Conclusion. For the patients with type 1 or 2 periampullary diverticulum or multiple CBD stones, careful followup is needed for the risk in recurrence of symptomatic CBD stone.

Study of renal stones complications in 200 patients in Tabriz, Iran

Directory of Open Access Journals (Sweden)

Hamid Noshad

2014-11-01

Full Text Available Introduction: Urinary stones are the third most common disease of the urinary. Renal stones may lead to some preventable complications. This study was designed to investigation and prediction of these complications. Methods: In this cross-sectional study, 200 patients with kidney stones were enrolled. Kidney stone was confirmed and proven in all patients referred to Sina and Shaikh Al-Rais clinics. Their demographic characteristics like gender, age, stone number, stone type, renal failure and bio-chemistry data were evaluated. Results: Of 200 patients, 130 cases (65.0% were male and 70 cases (35.0% were female. The mean age of patients was 41.30 ± 16.06 years. Type of stone was (when evaluation was possible was mixed (11.5%. However, the type of stone was not analyzed in 112 cases (56.0%. Among complications, recurrent infection was seen (16.0%, and staghorn stones were seen in 2.5% of patients. Dialysis was positive in 3 patients (1.5%. History of surgery was positive in 3 patients (1.5%. Extracorporeal shock wave lithotripsy (ESWL history was positive in 8%. In evaluated patients, the mean level of calcium was 8.83 ± 0.27, phosphorus was 4.60 ± 0.33, parathyroid hormone (PTH was 35.20 ± 14.22, uric acid was 4.98 ± 1.57, creatinine was 1.38 ± 1.02 and blood urea nitrogen level was 16.69 ± 11.54 mg/dl. Staghorn stones are significantly associated with progression to renal failure and subsequent complications such as hemodialysis (P = 0.001, surgery (P = 0.001. Recurrent infection was more frequent in calcium-containing stones (P = 0.001 and ESWL undergoing patients (P = 0.030. Stone numbers were more than 3 in hemodialyzed (HD patients (P = 0.001. Uric acid stones were more seen in HD patients (P = 0.170. Conclusion: According to results hemodialysis and recurrent infections are seen in patients with renal stones, and they may be detected in earlier with close periodic follow-up.

Predicting stone composition before treatment – can it really drive clinical decisions?

Science.gov (United States)

Bres–Niewada, Ewa; Radziszewski, Piotr

2014-01-01

Introduction Determination of stone composition is considered to be crucial for the choice of an optimal treatment algorithm. It is especially important for uric acid stones, which can be dissolved by oral chemolysis and for renal stones smaller than 2 cm, which can be treated with extracorporeal shockwave lithotripsy (ESWL). Material and methods This short review identifies the latest papers on radiological assessment of stone composition and presents a comprehensive evaluation of current scientific findings. Results Stone chemical composition is difficult to predict using standard CT imaging, however, attenuation index measured in Hounsfield units (HU) is related to ESWL outcome. Stone density >1000 HU can be considered predictive for ESWL failure. It seems that stone composition is meaningless in determining the outcome of ureterolithotripsy and percutaneous surgery. Alternative imaging techniques such as Dual–Energy CT or analysis of shape, density and homogeneity of stones on plain X–rays are used as promising methods of predicting stone composition and ESWL outcome. Conclusions New imaging techniques facilitate the identification of uric acid stones and ESWL–resistant stones. Therefore, they may help in selecting the best therapeutic option. PMID:25667761

Emergency extracorporeal shock wave lithotripsy (ESWL) for obstructing ureteral stones.

Science.gov (United States)

Tligui, M; El Khadime, M R; Tchala, K; Haab, F; Traxer, O; Gattegno, B; Thibault, P

2003-05-01

To evaluate emergency treatment of obstructing ureteral stones by in situ extracorporeal shock wave lithotripsy (ESWL) during acute renal colic. From January 1994 to February 2000, 200 patients (mean age: 42 years) were treated by ESWL (EDAP LT-02) for obstructing ureteral stones causing acute renal colic refractory to medical treatment or recurring within 24hours of such treatment. Stones were visualised by fluoroscopic imaging and/or ultrasound. Follow-up included radiological and/or ultrasound examinations and lasted three months. Mean stone size was 7mm (3-20mm). At three months, 164/200 (82%) patients were stone-free. This rate ranged from 79% to 83% according to the location of the stone, and from 75% to 86% according to the size of the stone. These differences in rate were not significant. Two or three ESWL sessions were required in 79 patients. ESWL was well tolerated in 90% of patients. The only complication was a case of pyelonephritis requiring the placement of a JJ stent, administration of antibiotics, and distant ureteroscopy. The 36 patients, in whom ESWL failed, underwent ureteroscopy (n=23) or lithotripsy with a Dornier machine (n=13). Non-deferred ESWL for acute renal colic secondary to obstructing ureteral stones has a satisfactory success rate and very low morbidity.

Is pre-operative imaging essential prior to ureteric stone surgery?

Science.gov (United States)

Youssef, F R; Wilkinson, B A; Hastie, K J; Hall, J

2012-09-01

The aim of this study was to identify patients not requiring ureteric stone surgery based on pre-operative imaging (within 24 hours) prior to embarking on semirigid ureteroscopy (R-URS) for urolithiasis. The imaging of all consecutive patients on whom R-URS for urolithiasis was performed over a 12-month period was reviewed. All patients had undergone a plain x-ray of the kidney, ureters and bladder (KUB), abdominal non-contrast computed tomography (NCCT-KUB) or both on the day of surgery. A total of 96 patients were identified for the study. Stone sizes ranged from 3 mm to 20 mm. Thirteen patients (14%) were cancelled as no stone(s) were identified on pre-operative imaging. Of the patients cancelled, 8 (62%) required NCCT-KUB to confirm spontaneous stone passage. One in seven patients were stone free on the day of surgery. This negates the need for unnecessary anaesthetic and instrumentation of the urinary tract, with the associated morbidity. Up-to-date imaging prior to embarking on elective ureteric stone surgery is highly recommended.

Clinical experience for radiolucent stones; A report of 27 cases

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyung Jee; Lee, Gil Ho [Dankook University, Seoul (Korea, Republic of)

1997-02-01

The cause of radiolucent filling defects in the upper urinary tract are malignant tumor, radiolucent stones, blood clots, air bubbles, congenital deformities of renal parenchyme, and various specific and non-specific infection and their sequence. So the differential diagnosis between malignancy and radiolucent stones is very important, and the exact and fast diagnosis of radiolucent stones is useful in excluding the possibility of malignancy. 27 cases with radiolucent stones were evaluated retrospectively for exact diagnosis and appropriate treatment method. Intravenous urography was done in all cases, and retrograde pyelography, ultrasonography, computed tomography and/or ureterorenoscopy were performed for diagnosis, if needed. Size of stones were measured below 10mm by transverse length in 19 cases (70.4%) with a range of 3 to 30mm. The locations of stones were pelvicalyceal system in 8 cases (29.6%) and ureter in 19 cases (70.4%). Among the diagnostic methods, computed tomography was used most frequency. ESWL with retrograde pyelography was most frequent used method of treatment, also simple hydration to small stone was effective. (author).

Clinical experience for radiolucent stones; A report of 27 cases

International Nuclear Information System (INIS)

Kim, Hyung Jee; Lee, Gil Ho

1997-01-01

The cause of radiolucent filling defects in the upper urinary tract are malignant tumor, radiolucent stones, blood clots, air bubbles, congenital deformities of renal parenchyme, and various specific and non-specific infection and their sequence. So the differential diagnosis between malignancy and radiolucent stones is very important, and the exact and fast diagnosis of radiolucent stones is useful in excluding the possibility of malignancy. 27 cases with radiolucent stones were evaluated retrospectively for exact diagnosis and appropriate treatment method. Intravenous urography was done in all cases, and retrograde pyelography, ultrasonography, computed tomography and/or ureterorenoscopy were performed for diagnosis, if needed. Size of stones were measured below 10mm by transverse length in 19 cases (70.4%) with a range of 3 to 30mm. The locations of stones were pelvicalyceal system in 8 cases (29.6%) and ureter in 19 cases (70.4%). Among the diagnostic methods, computed tomography was used most frequency. ESWL with retrograde pyelography was most frequent used method of treatment, also simple hydration to small stone was effective. (author)

Screening renal stone formers for distal renal tubular acidosis

DEFF Research Database (Denmark)

Osther, P J; Hansen, A B; Røhl, H F

1989-01-01

A group of 110 consecutive renal stone formers were screened for distal renal tubular acidosis (RTA) using morning fasting urinary pH (mfUpH) levels followed by a short ammonium chloride loading test in patients with levels above 6.0. In 14 patients (12.7%) a renal acidification defect was noted...... RTA in renal stone formers. Regardless of whether the acidification defect is primary or secondary to stone formation, however, all renal stone formers with distal RTA can expect to benefit from prophylactic alkaline therapy and it is recommended that the screening procedure, which is easy to use...

A giant urinary bladder stone in the mummy of Lebanese Maronite Patriarch Joseph Tyan (1760–1820) and its environmental and nutritional implications

International Nuclear Information System (INIS)

Capasso, L.; Licata, M.; Pinto, A.; Fernianos, F.; Azizi, T.; Manzoli, L.; Centrella, D.; D'anastasio, R.

2017-01-01

Introduction: Historical sources and anthropological investigations, with the indispensable support of radiology, bring to light pathological evidence of the past. Case presentation: The purpose of this article is to present the radiological investigation conducted on the mummy of the Maronite Joseph Tyan (1760–1820), a famous patriarch who guided the Lebanese Maronite community during a critical period of its history. The natural mummy of the Patriarch was temporarily removed from its burial site to certify the degree of preservation. Conventional radiography was necessary to determine the state of the internal organs and any physical abnormalities, and to clarify the degree of conservation of the mummy. Discussion: Radiological analysis uncovered an exceptional case of a large urinary bladder stone. This pathological evidence confirms historical documentary sources that in the last years of his life the Patriarch suffered from abdominal pain and urinary problems. We can suppose that the environment and diet of the Maronite community, limited by restricted agricultural resources, was the possible cause of the urinary bladder stone, as today the epidemiology of these diseases demonstrates links with mainly cereal diets in rural areas. - Highlights: • Paleoradiological analysis: a radiological approach to study mummies. • The anthropological and radiological analysis of the Mummy of Patriarch Joseph Tyan • Urinary bladder stone: radiological investigations. • Paleopathological literature of urinary bladder stone.

A Stone Resource Assignment Model under the Fuzzy Environment

Directory of Open Access Journals (Sweden)

Liming Yao

2012-01-01

to tackle a stone resource assignment problem with the aim of decreasing dust and waste water emissions. On the upper level, the local government wants to assign a reasonable exploitation amount to each stone plant so as to minimize total emissions and maximize employment and economic profit. On the lower level, stone plants must reasonably assign stone resources to produce different stone products under the exploitation constraint. To deal with inherent uncertainties, the object functions and constraints are defuzzified using a possibility measure. A fuzzy simulation-based improved simulated annealing algorithm (FS-ISA is designed to search for the Pareto optimal solutions. Finally, a case study is presented to demonstrate the practicality and efficiency of the model. Results and a comparison analysis are presented to highlight the performance of the optimization method, which proves to be very efficient compared with other algorithms.

Design Space Approach for Preservative System Optimization of an Anti-Aging Eye Fluid Emulsion.

Science.gov (United States)

Lourenço, Felipe Rebello; Francisco, Fabiane Lacerda; Ferreira, Márcia Regina Spuri; Andreoli, Terezinha De Jesus; Löbenberg, Raimar; Bou-Chacra, Nádia

2015-01-01

The use of preservatives must be optimized in order to ensure the efficacy of an antimicrobial system as well as the product safety. Despite the wide variety of preservatives, the synergistic or antagonistic effects of their combinations are not well established and it is still an issue in the development of pharmaceutical and cosmetic products. The purpose of this paper was to establish a space design using a simplex-centroid approach to achieve the lowest effective concentration of 3 preservatives (methylparaben, propylparaben, and imidazolidinyl urea) and EDTA for an emulsion cosmetic product. Twenty-two formulae of emulsion differing only by imidazolidinyl urea (A: 0.00 to 0.30% w/w), methylparaben (B: 0.00 to 0.20% w/w), propylparaben (C: 0.00 to 0.10% w/w) and EDTA (D: 0.00 to 0.10% w/w) concentrations were prepared. They were tested alone and in binary, ternary and quaternary combinations. Aliquots of these formulae were inoculated with several microorganisms. An electrochemical method was used to determine microbial burden immediately after inoculation and after 2, 4, 8, 12, 24, 48, and 168 h. An optimization strategy was used to obtain the concentrations of preservatives and EDTA resulting in a most effective preservative system of all microorganisms simultaneously. The use of preservatives and EDTA in combination has the advantage of exhibiting a potential synergistic effect against a wider spectrum of microorganisms. Based on graphic and optimization strategies, we proposed a new formula containing a quaternary combination (A: 55%; B: 30%; C: 5% and D: 10% w/w), which complies with the specification of a conventional challenge test. A design space approach was successfully employed in the optimization of concentrations of preservatives and EDTA in an emulsion cosmetic product.

Frequency of stone clearance after extracorporeal shockwave ...

African Journals Online (AJOL)

Objective: To determine the rate of stone clearance after extracorporeal shockwave lithotripsy (ESWL) for renal stones in adult patients with renal insufficiency. Subjects and methods: This is a cross-sectional descriptive study of 117 adult patients who underwent ESWL. The indications for ESWL were determined by the ...

EPR of some irradiated renal stones

International Nuclear Information System (INIS)

Koeseoglu, R.; Koeseoglu, E.; Koeksal, F.; Basaran, E.; Demirci, D.

2005-01-01

Some renal stones were investigated by electron paramagnetic resonance of their untreated, UV-photolyzed and gamma-irradiated states. Powder X-ray diffraction technique indicated that the renal stones were made mainly from CaC 2 O 4 , MgC 2 O 4 , MgCO 3 and NH 4 MgPO 4 .6H 2 O. Before radiation treatment, the renal stones yielded a signal that could be attributed to a C 2 O 4 - radical. UV-photolysis seems to slightly increase the intensity of this signal, but does not produce any new centres. Gamma-irradiation initially gives -CH 2 C (CH 3 )-R and CO 2 - radicals, and while the intensity of the -CH 2 C (CH 3 )-R signal decreases, the intensity of the CO 2 - signal increases as time elapses

"Piedra Franca": the same name for many different natural stones.

Science.gov (United States)

Pereira, Dolores; Navarro, Rafael; Baltuille, Jose Manuel

2014-05-01

The Spanish name "Piedra Franca" refers to all the stones of sedimentary origin that have uniform coloration and easeof cutting/carving in order to obtain dimensional blocks for construction. The first references to this denomination occurred during medieval times, when builders had to choose the best materials to construct magnificent cathedrals. The largest volume of such natural stones were extracted from Caen, northern France, and historic records use the English term, "freestone", ie stone easy to cut, and to work by the masons dedicated to build cathedrals ("freemasons") in contrast to the "roughstone", hard stones worked by the hard hewers or "rough masons". The original French name referred to the limestones extracted at Caen, but over time, the original meaning expanded to include other natural stones with similar coloration and ease to carve. Notably this included many sandstones that were used in adjacent countries such as Spain. In the latter, although the most popular for its importance in architectural heritage is the Villamayor sandstone from Salamanca, other historically important natural stones are also known as "Piedra Franca" including the calcarenite from Santa Pudia (Granada), the limestone from Alava, the sandstone from Jaen and the sandstone from Cádiz. All of them were used in the construction of Spanish architectonic heritage and share similar exterior characteristics. In fact, several are known as golden stones. However when conservation and restoration of architectonic heritage is involved, the correct and original material should be used. The existence of national networks (e.g. CONSTRUROCK) and international task groups (e.g. IUGS Heritage Stone Task Group) can help to properly characterize, document, and differentiate between the varieties of "Piedra Franca" and they should be consulted by builders, architects and any other stone professsionals involved in such activities. An error in choosing the natural stone can result in

Dual-source dual-energy CT for the differentiation of urinary stone composition: preliminary study

International Nuclear Information System (INIS)

Yang Qifang; Zhang Wanshi; Meng Limin; Shi Huiping; Wang Dong; Bi Yongmin; Li Xiangsheng; Fang Hong; Guo Heqing; Yan Jingmin

2011-01-01

Objective: To evaluate dual-source dual-energy CT (DSCT) for the differentiation of' urinary stone composition in vitro. Methods: Ninety-seven urinary stones were obtained by endoscopic lithotripsy and scanned using dual-source dual-energy CT. The stones were divided into six groups according to infrared spectroscopy stone analysis: uric acid (UA) stones (n=10), cystine stones (n=5), struvite stones (n=6), calcium oxalate (CaOx) stones (n=22), mixed UA stones (n=7) and mixed calcium stones (n=47). Hounsfield units (HU) of each stone were recorded for the 80 kV and the 140 kV datasets by hand-drawing method. HU difference, HU ratio and dual energy index (DEI) were calculated and compared among the stone groups with one-way ANOVA. Using dual energy software to determine the composition of all stones, results were compared to infrared spectroscopy analysis. Results: There were statistical differences in HU difference [(-17±13), (229±34), (309±45), (512±97), (201±64) and (530±71) HU respectively], in HU ratio (0.96±0.03, 1.34±0.04, 1.41±0.03, 1.47±0.03, 1.30±0.07, and 1.49±0.03 respectively), and DEI (-0.006±0.004, 0.064±0.007, 0.080± 0.007, 0.108±0.011, 0.055±0.014 and 0.112±0.008 respectively) among different stone groups (F= 124.894, 407.028, 322.864 respectively, P<0.01). There were statistical differences in HU difference, HU ratio and DEI between UA stones and the other groups (P<0.01). There were statistical differences in HU difference, HU ratio and DEI between CaOx or mixed calcium stones and the other four groups (P< 0.01). There was statistical difference in HU ratio between cystine and struvite stones (P<0.01). There were statistical differences in HU difference, HU ratio and DEI between struvite and mixed UA stones (P< 0.05). Dual energy software correctly characterized 10 UA stones, 4 cystine stones, 22 CaOx stones and 6 mixed UA stones. Two struvite stones were considered to contain cystine. One cystine stone, 1 mixed UA stone, 4

In vitro differentiation of renal stone composition using dual-source, dual-energy CT

International Nuclear Information System (INIS)

Zhou Changsheng; Zhang Longjiang; Xu Feng; Qi Li; Zhao Yan'e; Zheng Ling; Huang Wei; Liu Youhuang; Lu Guangming

2012-01-01

Objective: To evaluate the ability of dual-source. dual-energy CT in differentiating uric acid stones from non-uric acid stones with infrared spectroscopy as reference standard. Materials and Methods: Urinary calculus from 308 patients were scanned in first generation dual-source CT with dual-energy mode between July 2011 and June 2012. Renal Stone application was used to analyze their composition. The uric acid stones color were coded red and non-uric acid stones were blue. CT values were measured in 60 selective urinary calculus including 30 uric acid stones and 30 non-uric acid stones. The accuracy of dual energy CT to differentiate uric acid and no-uric acid stones was calculated. Results: Of 308 patients, 60 patients had uric acid stones and 248 non-uric acid stones. No difference was found for uric acid stone at 80 kV and 140 kV (375.8±69.2 HU vs. 374.1±69.4 HU; t=-0.217, P=0.830), while CT values of non-uric acid stones were higher at 80 kV than those at 140 kV (1455.1±312.4 HU vs. 1039.6±194.4 HU; t=-12.16. P<0.001). CT values of non-uric acid stones at 80 kV, 140 kV, and average weighted images (1455.1±312.4 HU, 1 039.6±194.4 HU, and 882.0±176.4 HU, respectively) were higher than those of uric acid stones (375.8±69.2 HU, 374.1±69.4 HU, and 366.3±80.1 HU, respectively; P<0.001). With infrared spectrum findings as reference standard, the accuracy of dual energy CT in differentiating uric acid stones from non-uric acid stones was 100%. Conclusions: Dual-source, dual-energy CT can accurately differentiate uric acid stones from non-uric acid stones, and plays an important role in treatment planning of renal stones. (authors)

Patients' selection for treatment of caliceal diverticular stones with extracorporeal shock wave lithotripsy

International Nuclear Information System (INIS)

Lee, Won Hong; Lee, Hee Jeong; Son, Soon Yong; Kang, Seong Ho; Cho, Cheong Chan; Ryu, Meung Sun; Kim, Seung Kook

2001-01-01

Symptoms of caliceal diverticular stones are commonly associated with pain, recurrent urinary tract infection and hematuria. The aim of this study is to select the proper patient for the application of more successful extracorporeal shock wave lithotripsy(ESWL) as a treatment of caliceal diverticular stone. 16 patients with caliceal diverticular stones were treated with ESWL, and all patients had single caliceal diverticulum. The diagnosis of caliceal diverticulum with stones was made by intraveneous pyelography to all patients. On these intravenous pyelogram, we also classified diverticular type, whether the diverticular neck is connected with urinary tract patently, diverticular site and stone number and size. All patients were followed after ESWL by plain film of the kidneys, ureters and bladder and interviewed. Of all patients 44% was shown stone-free completely, also 83% was rendered symptom-free. All patients whose diverticular neck connected with urinary tract patently on the intraveneous pyelogram became stone-free. Of solitary stone 60% and multiple stones (more than 2) 17% became symptom-free. The patients with infection before ESWL 75% had residual stones, of these patients 33% had slightly flank pain, and 25% of patients with stones recurred become stone-free. We propose that more successful ESWL for patients with caliceal diverticular stones select satisfactory patients including that the diverticular neck is connected with urinary tract patently, solitary stone and no infection simultaneously

Management of Asymptomatic Renal Stones in Astronauts

Science.gov (United States)

Reyes, David; Locke, James

2016-01-01

Introduction: Management guidelines were created to screen and manage asymptomatic renal stones in U.S. astronauts. The risks for renal stone formation in astronauts due to bone loss and hypercalcuria are unknown. Astronauts have a stone risk which is about the same as commercial aviation pilots, which is about half that of the general population. However, proper management of this condition is still crucial to mitigate health and mission risks in the spaceflight environment. Methods: An extensive review of the literature and current aeromedical standards for the monitoring and management of renal stones was done. The NASA Flight Medicine Clinic's electronic medical record and Longitudinal Survey of Astronaut Health were also reviewed. Using this work, a screening and management algorithm was created that takes into consideration the unique operational environment of spaceflight. Results: Renal stone screening and management guidelines for astronauts were created based on accepted standards of care, with consideration to the environment of spaceflight. In the proposed algorithm, all astronauts will receive a yearly screening ultrasound for renal calcifications, or mineralized renal material (MRM). Any areas of MRM, 3 millimeters or larger, are considered a positive finding. Three millimeters approaches the detection limit of standard ultrasound, and several studies have shown that any stone that is 3 millimeters or less has an approximately 95 percent chance of spontaneous passage. For mission-assigned astronauts, any positive ultrasound study is followed by low-dose renal computed tomography (CT) scan, and flexible ureteroscopy if CT is positive. Other specific guidelines were also created. Discussion: The term "MRM" is used to account for small areas of calcification that may be outside the renal collecting system, and allows objectivity without otherwise constraining the diagnostic and treatment process for potentially very small calcifications of uncertain

Building materials as intrinsic sources of sulphate: A hidden face of salt weathering of historical monuments investigated through multi-isotope tracing (B, O, S)

International Nuclear Information System (INIS)

Kloppmann, W.; Bromblet, P.; Vallet, J.M.; Verges-Belmin, V.; Rolland, O.; Guerrot, C.; Gosselin, C.

2011-01-01

Sulphate neoformation is a major factor of degradation of stone monuments. Boron, sulphur and oxygen isotope signatures were investigated for five French historical monuments (Bourges, Chartres and Marseille cathedrals, Chenonceau castle, and Versailles garden statues) to investigate the role of intrinsic sulphate sources (gypsum plasters and mortars) in stone degradation, compared to the influence of extrinsic sources such as atmospheric pollution. Gypsum plasters and gypsum-containing mortars fall systematically in the δ 34 S and δ 18 O range of Paris Basin Eocene evaporites indicating the origin of the raw materials (so-called 'Paris plaster'). Black crusts show the typical S and O isotope signatures observed elsewhere in Europe that can be attributed to atmospheric pollution, together with a marine component for Marseille. Boron isotopes for black crusts indicate coal combustion as principal boron source. Mortar isotope compositions discriminate three types, one similar to gypsum plasters, one strongly depleted in 34 S, attributed to pyrite oxidation, and a third one close to atmospheric sulphates. The isotopic composition of sulphates and boron of most degraded building stones of the different monuments is well explained by the identified sulphate sources. In several cases (in particular for Chenonceau and Bourges, to some extent for Chartres), the impact of gypsum plaster as building and restoration material on the degradation of the stones in its vicinity was clearly demonstrated. The study illustrates the usefulness of multi-isotope studies to investigate stone degradation factors, as the combination of several isotope systematics increases the discriminatory power of isotope studies with respect to contaminant sources. - Research Highlights: → Insight in stone weathering mechanisms by multi-isotope fingerprinting (B, S, O). → Intrinsic sulphate sources (gypsum plaster, mortar) contribute to stone degradation. → Origin of building materials

Building materials as intrinsic sources of sulphate: A hidden face of salt weathering of historical monuments investigated through multi-isotope tracing (B, O, S)

Energy Technology Data Exchange (ETDEWEB)

Kloppmann, W., E-mail: w.kloppmann@brgm.fr [BRGM, BP 6009, F-45060 Orleans cedex 2 (France); Bromblet, P.; Vallet, J.M. [CICRP, 21, rue Guibal, F-13003 Marseille (France); Verges-Belmin, V. [LRMH, 29, rue de Paris, F-77420 Champs sur Marne (France); Rolland, O. [Independent restorer, 3, rue du Gue, 37270 Montlouis s/Loire (France); Guerrot, C. [BRGM, BP 6009, F-45060 Orleans cedex 2 (France); Gosselin, C. [BRGM, BP 6009, F-45060 Orleans cedex 2 (France); LRMH, 29, rue de Paris, F-77420 Champs sur Marne (France)

2011-04-01

Sulphate neoformation is a major factor of degradation of stone monuments. Boron, sulphur and oxygen isotope signatures were investigated for five French historical monuments (Bourges, Chartres and Marseille cathedrals, Chenonceau castle, and Versailles garden statues) to investigate the role of intrinsic sulphate sources (gypsum plasters and mortars) in stone degradation, compared to the influence of extrinsic sources such as atmospheric pollution. Gypsum plasters and gypsum-containing mortars fall systematically in the {delta}{sup 34}S and {delta}{sup 18}O range of Paris Basin Eocene evaporites indicating the origin of the raw materials (so-called 'Paris plaster'). Black crusts show the typical S and O isotope signatures observed elsewhere in Europe that can be attributed to atmospheric pollution, together with a marine component for Marseille. Boron isotopes for black crusts indicate coal combustion as principal boron source. Mortar isotope compositions discriminate three types, one similar to gypsum plasters, one strongly depleted in {sup 34}S, attributed to pyrite oxidation, and a third one close to atmospheric sulphates. The isotopic composition of sulphates and boron of most degraded building stones of the different monuments is well explained by the identified sulphate sources. In several cases (in particular for Chenonceau and Bourges, to some extent for Chartres), the impact of gypsum plaster as building and restoration material on the degradation of the stones in its vicinity was clearly demonstrated. The study illustrates the usefulness of multi-isotope studies to investigate stone degradation factors, as the combination of several isotope systematics increases the discriminatory power of isotope studies with respect to contaminant sources. - Research Highlights: {yields} Insight in stone weathering mechanisms by multi-isotope fingerprinting (B, S, O). {yields} Intrinsic sulphate sources (gypsum plaster, mortar) contribute to stone degradation

Weathering methods for preservative treated wood and their applicability for fire retarded wood

NARCIS (Netherlands)

Voss, A.

1999-01-01

preservative treated wood. The aim of the presentation is to inform you about current testing methods and to discuss their applicability to test fire retarded wood in outdoor use. Assuming that fire retardants will only be used in out of ground contact, only those methods are mentioned, which fit

Estimation of bearing capacity of floating group of stone columns

OpenAIRE

Fattah, Mohammed Y.; Al-Neami, Mohammed A.; Shamel Al-Suhaily, Ahmed

2017-01-01

Stone column is one of the ground improvement techniques. This technique has a proven performance, short time schedule, durability, constructability and low costs. The stone column technique has been used as a method of reinforcement of soft ground over the past 30 years. The bearing capacity of the stone column still has high level of uncertainties because the existing formulas for the estimation of the bearing capacity are general and do not take into consideration the type of the stone col...

Dietary supplementation with olive stone meal in growing rabbits

Directory of Open Access Journals (Sweden)

Gerolamo Xiccato

2010-01-01

Full Text Available Olive stone meal is a low-digested fibre source potentially useful in the prevention of digestive troubles in growing rabbit permitting a better balance of dietary fibre fractions. To evaluate its efficacy, three experimental diets containing 0, 3 or 6% olive stone meal were fed to 222 rabbits from weaning (28 d to slaughter (73 d. Olive stone inclusion increased the proportion of large dietary particles while did not affect growth performance, digestive physiology and carcass and meat quality. Due to optimum health status observed in all experimental groups, the preventive action of olive stone meal against the occurrence of digestive troubles was not proven.

Risk factors for recurrent symptomatic pigmented biliary stones after percutaneous transhepatic biliary extraction.

Science.gov (United States)

Kim, Dong Won; Lee, Sang Yun; Cho, Jin-Han; Kang, Myong Jin; Noh, Myung Hwan; Park, Byeong-Ho

2010-07-01

To evaluate risk factors for the recurrence of biliary stones after a percutaneous transhepatic biliary stone extraction. The procedures were performed on 339 patients between July 2004 and December 2008 (54 months). Medical records and images were retrospectively reviewed for 135 patients (mean age, 66.4 years; 83 men and 52 women) who had undergone follow-up for a mean of 13.2 months (range, 3-37 months). To evaluate risk factors for the recurrence of biliary stones, variables were evaluated with univariate and multivariate analyses. Variables included sex, age, stone location, number of stones, stone size, presence of a peripapillary diverticulum, application of antegrade sphincteroplasty, presence of a biliary stricture, largest biliary diameter before the procedure, and gallbladder status. Thirty-three of the 135 patients (24%) had recurrent symptomatic biliary stones and underwent an additional extraction. The mean time to recurrence was 17.2 months +/- 8.7. Univariate analysis of risk factors for recurrence of biliary stones demonstrated that location, number of stones, stone size, application of antegrade sphincteroplasty, presence of a biliary stricture, and biliary diameter were significant factors (P or =6; relative risk, 64.8; 95% confidence interval: 5.8, 717.6) and stone size (> or =14 mm; relative risk, 3.8; 95% confidence interval: 1.138, 13.231) were determined to be significant risk factors. The independent risk factors for recurrence of symptomatic biliary stones after percutaneous transhepatic biliary stone extraction were a stone size of at least 14 mm and the presence of at least six stones. Copyright 2010 SIR. Published by Elsevier Inc. All rights reserved.

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.

Effect of Diuretics on Ureteral Stone Therapy with Extracorporeal Shock Wave Lithotripsy

Directory of Open Access Journals (Sweden)

Zomorrodi A

2008-01-01

Full Text Available To evaluate the effect of diuretics on ureteral stone fragmentation and clearance during therapy with extra corporeal shock wave lithotripsy (ESWL, we studied 87 patients with ureteral stone at different levels and treated with ESWL. The patients were randomized into two groups treated by standard ESWL; the treatment protocol included 3500 shock wave per patient in each session, energy of the shock in two groups was 13 to 9 kv per patient, and the number of sessions was 3 per patient. The first group included 43 patients who received only ESWL, while the second group of 44 patients received as well 40 mg of furosemide. Stone fragmentation rate was 81% and 93.1% and stone clearance rate was 68.2% and 88.4% for the first and the second groups, respectively. With diuretics, fragmentation was18.8% more in the middle ureteral stones, 16.9% more in the upper tract stones, and 5.4% more in the distal stones. Moreover, clearance of fragmented stones was 38%, 28%, 15.4% more at middle and upper and distal ureteral stone, respectively. We conclude that the stone fragmentation and clearance were higher with ESWL and diuretics than without diuresis. Diuresis is safe and has some advantage at increasing the effect of ESWL on ureteral stones especially the middle ureteral calculi.

Dental pulp stone formation during orthodontic treatment: A ...

African Journals Online (AJOL)

2015-06-21

Jun 21, 2015 ... the presence of dental pulp stone, gender, age, tooth type and arches. Results: Dental pulp ... primary and permanent dentition.[1] Dental pulp stones .... interpretation provided training to familiarize the other observer with the ...

Pyramidal anchor stone from Baga waters of Goa, west coast of India

Digital Repository Service at National Institute of Oceanography (India)

Tripati, S.

. Pyramidal anchor stones have an apex hole which goes up to the round hole, however Goa anchor stone has no such perforation, but, instead has a rectangular cutting on the apex. The anchor stone is compared with Greek pyramidal anchor stones, and probably...

Is ridge preservation/augmentation at periodontally compromised extraction sockets safe? A retrospective study.

Science.gov (United States)

Kim, Jung-Ju; Ben Amara, Heithem; Schwarz, Frank; Kim, Hae-Young; Lee, Jung-Won; Wikesjö, Ulf M E; Koo, Ki-Tae

2017-10-01

This study aimed to evaluate the safety of ridge preservation/augmentation procedures when performed at compromised extraction sockets. Patients subject to ridge preservation/augmentation at periodontally compromised sockets at Seoul National University Dental Hospital (SNUDH) were evaluated in a chart review. Tooth extractions due to acute infection were not included in our study as chronically formed lesions are the only lesions that can be detected from radiographic images. If inflammatory symptoms persisted following ridge preservation/augmentation and antimicrobial and anti-inflammatory therapy, the patient was categorized as a re-infection case and implanted biomaterial removed. Of 10,060 patients subject to tooth extractions at SNUDH, 2011 through 2015, 297 cases meeting inclusion criteria were reviewed. The severity and type of lesions were not specific because extracting data was only done by radiographic images and chart records. The review identified eight patients exhibiting inflammatory symptoms that required additional antimicrobial and anti-inflammatory therapy. Within this group, re-infection occurred in two patients requiring biomaterials removal. The final safety rate for the ridge preservation/augmentation was 99.3%. None of the demographic factors, systemic conditions or choice of biomaterial affected the safety of ridge preservation/augmentation. Alveolar ridge preservation/augmentation at periodontally compromised sockets appears safe following thorough removal of infectious source. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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.

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.

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.

Bladder stones in catheterized spinal cord-injured patients in Nigeria

African Journals Online (AJOL)

Objective: The objective was to determine the incidence of bladder stones in patients with spinal cord injury (SCI) and to assess if catheter encrustation or positive urinary culture of Proteus mirabilis is predictive of bladder stones. Background: Bladder stones are common urological complication in those with SCI managed ...

Extracorporeal shock wave lithotripsy of intrahepatic stones with piezoelectric lithotriptor: in vitro study

International Nuclear Information System (INIS)

Choi, Byung Ihn; Yoon, Chong Hyun; Park, Yong Hyun; Han, Joon Koo; Yoon, Yong Bum; Shin, Yong Moon; Kim, Jin Q; Kim, Chu Wan; Han, Man Chung

1992-01-01

This study was designed to investigate effectiveness of fragmentation during lithotripsy using 103 intrahepatic stones collected from 10 patients, who had previously undergone biliary surgery. The size of each stone was measured and sonography was performed for the evaluation of the sonographic type of the stones. In vitro lithotripsy was performed on individual stones using piezoelectric lithotriptor to evaluate the fragmentation rate and average number of shock waves for fragmentation. Chemical analysis of each stone was done to determine chemical composition including calcium, bilirubin, and cholesterol. The size of the stones was from 5 mm to 20 mm in diameter. Sonographic type I (echo of whole stone with posterior acoustic shadow) was 68, and type II (are-like strong surface echo of stone with clear posterior acoustic shadow) was 35 in number. The majority (78%) of stones in group I (5-9 mm in diameter) showed sonographic type I characteristics, and 62% of stones in group 3 (larger than 15 mm in diameter) showed sonographic type II characteristics. There was a positive correlation between the size and sonographic type of stones. Fragmentation rates of stones were 100% in group I, 71.9% in group 2 (10-15 mm in diameter), 43.8% in group 3, respectively. Fragmentation rates of stones with sonographic type I and II were 91.2%, 65.7%, respectively. The average number of shock waves for partial and complete fragmentation was 2753 ± 4937 and 6219 ± 10133, respectively. There was a positive correlation between the number of shock waves for fragmentation and diameter of stones (r = 0.618, ρ < 0.05). There was no correlation between the number of shock waves for fragmentation and chemical composition of stones. In conclusion, the most important variable determining the degree of fragmentation of intrahepatic stones using ESWL is not their chemical composition but their size and sonographic characteristics

Extracorporeal shock wave lithotripsy of intrahepatic stones with piezoelectric lithotriptor: in vitro study

Energy Technology Data Exchange (ETDEWEB)

Choi, Byung Ihn; Yoon, Chong Hyun; Park, Yong Hyun; Han, Joon Koo; Yoon, Yong Bum; Shin, Yong Moon; Kim, Jin Q; Kim, Chu Wan; Han, Man Chung [Seoul National University, College of Medicine, Seoul (Korea, Republic of)

1992-05-15

This study was designed to investigate effectiveness of fragmentation during lithotripsy using 103 intrahepatic stones collected from 10 patients, who had previously undergone biliary surgery. The size of each stone was measured and sonography was performed for the evaluation of the sonographic type of the stones. In vitro lithotripsy was performed on individual stones using piezoelectric lithotriptor to evaluate the fragmentation rate and average number of shock waves for fragmentation. Chemical analysis of each stone was done to determine chemical composition including calcium, bilirubin, and cholesterol. The size of the stones was from 5 mm to 20 mm in diameter. Sonographic type I (echo of whole stone with posterior acoustic shadow) was 68, and type II (are-like strong surface echo of stone with clear posterior acoustic shadow) was 35 in number. The majority (78%) of stones in group I (5-9 mm in diameter) showed sonographic type I characteristics, and 62% of stones in group 3 (larger than 15 mm in diameter) showed sonographic type II characteristics. There was a positive correlation between the size and sonographic type of stones. Fragmentation rates of stones were 100% in group I, 71.9% in group 2 (10-15 mm in diameter), 43.8% in group 3, respectively. Fragmentation rates of stones with sonographic type I and II were 91.2%, 65.7%, respectively. The average number of shock waves for partial and complete fragmentation was 2753 {+-} 4937 and 6219 {+-} 10133, respectively. There was a positive correlation between the number of shock waves for fragmentation and diameter of stones (r = 0.618, {rho} < 0.05). There was no correlation between the number of shock waves for fragmentation and chemical composition of stones. In conclusion, the most important variable determining the degree of fragmentation of intrahepatic stones using ESWL is not their chemical composition but their size and sonographic characteristics.

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.

Percutaneous nephrolithotomy versus extracorporeal shock wave lithotripsy for moderate sized kidney stones.

Science.gov (United States)

Deem, Samuel; Defade, Brian; Modak, Asmita; Emmett, Mary; Martinez, Fred; Davalos, Julio

2011-10-01

To compare the outcomes of percutaneous nephrolithotomy (PNL) and extracorporeal shock wave lithotripsy (ESWL) for moderate sized (1-2 cm) upper and middle pole renal calculi in regards to stone clearance rate, morbidity, and quality of life. All patients diagnosed with moderate sized upper and middle pole kidney stones by computed tomography (CT) were offered enrollment. They were randomized to receive either ESWL or PNL. The SF-8 quality of life survey was administered preoperatively and at 1 week and 3 months postoperatively. Abdominal radiograph at 1 week and CT scan at 3 months were used to determine stone-free status. All complications and outcomes were recorded. PNL established a stone-free status of 95% and 85% at 1 week and 3 months, respectively, whereas ESWL established a stone-free status of 17% and 33% at 1 week and 3 months, respectively. Retreatment in ESWL was required in 67% of cases, with 0% retreatment in PNL. Stone location, stone density, and skin-to-stone distance had no impact on stone-free rates at both visits, irrespective of procedure. Patient-reported outcomes, including overall physical and mental health status, favored a better quality of life for patients who had PNL performed. PNL more often establishes stone-free status, has a more similar complication profile, and has similar reported quality of life at 3 months when compared with ESWL for moderate-sized kidney stones. PNL should be offered as a treatment option to all patients with moderate-sized kidney stones in centers with experienced endourologists. Copyright © 2011 Elsevier Inc. All rights reserved.

Edge scour in current adjacent to stone covers

DEFF Research Database (Denmark)

Petersen, Thor Ugelvig; Sumer, B. Mutlu; Meyer, Knud Erik

The present paper reports some early results of an experimental investigation of edge scour in currents. Two kinds of measurements are made (1) Particle Image Velocimetry (PIV) measurements of secondary currents that take place near a junction between the stone cover and the sand bed in a clear......-water experiment; and (2) scour measurements in actual scour experiment in the live-bed regime. The early results indicate that edge scour in a steady current propagating in-line with a stone layer is caused by the combined action of two effects; (1) Primary flow and (2) Secondary flow. The primary flow stirs up...... the sediment and puts into suspension, and the secondary flow carries it away from the junction between the stone layer and the sand bed, resulting in a scour hole forming adjacent to the toe of the stone layer....

Ultrasonic propulsion of kidney stones: preliminary results of human feasibility study.

Science.gov (United States)

Bailey, Michael; Cunitz, Bryan; Dunmire, Barbrina; Paun, Marla; Lee, Franklin; Ross, Susan; Lingeman, James; Coburn, Michael; Wessells, Hunter; Sorensen, Mathew; Harper, Jonathan

2014-09-03

One in 11 Americans has experienced kidney stones, with a 50% average recurrence rate within 5-10 years. Ultrasonic propulsion (UP) offers a potential method to expel small stones or residual fragments before they become a recurrent problem. Reported here are preliminary findings from the first investigational use of UP in humans. The device uses a Verasonics ultrasound engine and Philips HDI C5-2 probe to generate real-time B-mode imaging and targeted "push" pulses on demand. There are three arms of the study: de novo stones, post-lithotripsy fragments, and the preoperative setting. A pain questionnaire is completed prior to and following the study. Movement is classified based on extent. Patients are followed for 90 days. Ten subjects have been treated to date: three de novo , five post-lithotripsy, and two preoperative. None of the subjects reported pain associated with the treatment or a treatment related adverse event, beyond the normal discomfort of passing a stone. At least one stone was moved in all subjects. Three of five post-lithotripsy subjects passed a single or multiple stones within 1-2 weeks following treatment; one subject passed two (1-2 mm) fragments before leaving clinic. In the pre-operative studies we successfully moved 7 - 8 mm stones. In four subjects, UP revealed multiple stone fragments where the clinical image and initial ultrasound examination indicated a single large stone.

WEATHER INDEX- THE BASIS OF WEATHER DERIVATIVES

Directory of Open Access Journals (Sweden)

Botos Horia Mircea

2011-07-01

Full Text Available This paper approaches the subject of Weather Derivatives, more exactly their basic element the weather index. The weather index has two forms, the Heating Degree Day (HDD and the Cooling Degree Day (CDD. We will try to explain their origin, use and the relationship between the two forms of the index. In our research we started from the analysis of the weather derivatives and what they are based on. After finding out about weather index, we were interested in understanding exactly how they work and how they influence the value of the contract. On the national level the research in the field is scares, but foreign materials available. The study for this paper was based firstly on reading about Weather Derivative, and then going in the meteorogical field and determining the way by which the indices were determined. After this, we went to the field with interest in the indices, such as the energy and gas industries, and figured out how they determined the weather index. For the examples we obtained data from the weather index database, and calculated the value for the period. The study is made on a period of five years, in 8 cities of the European Union. The result of this research is that we can now understand better the importance of the way the indices work and how they influence the value of the Weather Derivatives. This research has an implication on the field of insurance, because of the fact that weather derivative are at the convergence point of the stock markets and the insurance market. The originality of the paper comes from the personal touch given to the theoretical aspect and through the analysis of the HDD and CDD index in order to show their general behaviour and relationship.

Accelerated stone deterioration induced by forest clearance around the Angkor temples.

Science.gov (United States)

André, Marie-Françoise; Vautier, Franck; Voldoire, Olivier; Roussel, Erwan

2014-09-15

The present study provides the first quantitative assessment of the deteriorative impact of forest clearance on susceptible sandstone masonries. At Ta Keo, a 1000yr-old temple cleared of the Angkor forest in the early 20th century, GIS-based analysis of historic imagery indicates an average ten-fold increase in stone loss rates (0.2 instead of 0.02% per year). This accelerated decay is assigned to the climatic stress provoked by the exposure of fragile ornamented sandstones to the harsh impact of tropical sunshine and monsoon rains. Comparative climate monitoring with the Beng Mealea temple, still located in a forested environment, suggests a three-fold post-clearance increase in daily temperature and humidity ranges, which is conducive to enhanced swelling-shrinking movements responsible for accelerated sandstone contour scaling. Comparative visual assessment based on a customised 7-point scale of mechanical weathering confirms the protective role of canopy, with 79% of decorative motifs still almost free of mechanical weathering in the forest (against 7% at the cleared site). Disruption of archaeological structures by roots of individual trees can be locally observed at Angkor, but this does not negate the dominant overall buffering function of the forest cover. At Angkor and other cultural heritage sites, this bioprotective 'umbrella effect' should be considered as a valuable ecosystem service to be taken into account when defining and implementing strategies of sustainable management. Copyright © 2014 Elsevier B.V. All rights reserved.

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.

Process for altering the colour of hard stones

International Nuclear Information System (INIS)

Samoilovich, M.I.; Shaposhniko, A.A.; Turinge, A.P.; Vakhidov, S.A.; Nurullaev, Ergash.

1981-01-01

Process for altering the colour of hard stones and articles made with such stones, used in the jewellery trade, consisting in treating the hard stones in a neutron reactor and gamma particles accompanying them, whereby the treatment is performed with fast neutrons of at least 0.5 MeV, at integral doses of 5x10 15 to 1x10 18 neutrons/cm 2 , and gamma radiations, at integral doses of 5x10 6 to 1x10 9 R, at temperatures under 300 0 C [fr

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.

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

The Cost-Effectiveness of Treatment Modalities for Ureteral Stones

Directory of Open Access Journals (Sweden)

Justin Ji-Yuen Siu MD

2016-10-01

Full Text Available Additional intervention and medical treatment of complications may follow the primary treatment of a ureteral stone. We investigated the cost of the treatment of ureteral stone(s within 45 days after initial intervention by means of retrospective analysis of the National Health Insurance Research Database of Taiwan. All patients of ages ≥20 years diagnosed with ureteral stone(s( International Classification of Diseases, Ninth Revision, Clinical Modification/ICD-9-CM: 592.1 from January 2001 to December 2011 were enrolled. We included a comorbidity code only if the diagnosis appeared in at least 2 separate claims in a patient’s record. Treatment modalities (code included extracorporeal shock-wave lithotripsy (SWL; 98.51, ureteroscopic lithotripsy (URSL; 56.31, percutaneous nephrolithotripsy (PNL; 55.04, (open ureterolithotomy (56.20, and laparoscopy (ie, laparoscopic ureterolithotomy; 54.21. There were 28 513 patients with ureteral stones (13 848 men and 14 665 women in the randomized sample of 1 million patients. The mean cost was 526.4 ± 724.1 United States Dollar (USD. The costs of treatment were significantly increased in patients with comorbidities. The costs of treatment among each primary treatment modalities were 1212.2 ± 627.3, 1146.7 ± 816.8, 2507.4 ± 1333.5, 1533.3 ± 1137.1, 2566.4 ± 2594.3, and 209.8 ± 473.2 USD in the SWL, URSL, PNL, (open ureterolithotomy, laparoscopy (laparoscopic ureterolithotomy, and conservative treatment group, respectively. In conclusion, URSL was more cost-effective than SWL and PNL as a primary treatment modality for ureteral stone(s when the possible additional costs within 45 days after the initial operation were included in the calculation.

Medical expulsive treatment of distal ureteral stone using tamsulosin

International Nuclear Information System (INIS)

Ahmad, H.; Azim, W.; Akmal, M.; Murtaza, B.

2015-01-01

Many minimally invasive interventional techniques as well as expectant treatments exist for the management of lower ureteric calculi. This study was conducted to evaluate the efficacy of tamsulosin as an expulsive pharmacologic therapy for the treatment of distal ureteral stone. Methods: This randomized control trial included 100 patients over 18 years of age with stone Size = 8mm in distal 1/3 of ureter. Patients were randomly assigned into two groups (A and B). Group A Patients were given Capsule Tamsulosin 0.4 mg, 1 daily up to 4 weeks while group B patients were given placebo, 1 Capsule daily up to 4 weeks. The primary endpoint was expulsion rate. A written informed consent was taken from all the patients. Expulsion time, need for analgesics, need for hospitalization and drug side effects were secondary endpoints. Results: A total of 49 patients in group A and 48 patients in group B reported back, therefore 97 out of 100 patients were evaluated. Mean age of the patients was 36.34 years (range 18-57 years). Mean stone size was 5.78 mm (range 4-8 mm) in greatest dimension. A stone expulsion rate of 85.71% (42 patients) was noted in group A and 54.20% (26 patients) in group B. Group A revealed a statistically significant advantage in term of stone expulsion rate (p=0.032). Considering expulsion time in days group A showed statistically significant advantage (p=0.015). Regarding age, sex, stone size and stone lateralization (right/left), there was no significant difference between the group A and B. No drug side effects were noted in both the groups. Conclusion: By using tamsulosin a higher stone expulsion rates can be achieved in a shorter time. More randomized control trials are required to establish tamsulosin as a standard medical expulsive treatment for small distal ureteric calculus. (author)

Extended Leach Testing of Simulated LAW Cast Stone Monoliths

Energy Technology Data Exchange (ETDEWEB)

Serne, R. Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Williams, Benjamin D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jung, H. B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-07-09

This report describes the results from long-term laboratory leach tests performed at Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions (WRPS) to evaluate the release of key constituents from monoliths of Cast Stone prepared with four simulated low-activity waste (LAW) liquid waste streams. Specific objectives of the Cast Stone long-term leach tests described in this report focused on four activities: 1. Extending the leaching times for selected ongoing EPA-1315 tests on monoliths made with LAW simulants beyond the conventional 63-day time period up to 609 days reported herein (with some tests continuing that will be documented later) in an effort to evaluate long-term leaching properties of Cast Stone to support future performance assessment activities. 2. Starting new EPA-1315 leach tests on archived Cast Stone monoliths made with four LAW simulants using two leachants (deionized water [DIW] and simulated Hanford Integrated Disposal Facility (IDF) Site vadose zone pore water [VZP]). 3. Evaluating the impacts of varying the iodide loading (starting iodide concentrations) in one LAW simulant (7.8 M Na Hanford Tank Waste Operations Simulator (HTWOS) Average) by manufacturing new Cast Stone monoliths and repeating the EPA-1315 leach tests using DIW and the VZP leachants. 4. Evaluating the impacts of using a non-pertechnetate form of Tc that is present in some Hanford tanks. In this activity one LAW simulant (7.8 M Na HTWOS Average) was spiked with a Tc(I)-tricarbonyl gluconate species and then solidified into Cast Stone monoliths. Cured monoliths were leached using the EPA-1315 leach protocol with DIW and VZP. The leach results for the Tc-Gluconate Cast Stone monoliths were compared to Cast Stone monoliths pertechnetate.

Epilithic and endolithic bacterial communities in limestone from a Maya archaeological site.

Science.gov (United States)

McNamara, Christopher J; Perry, Thomas D; Bearce, Kristen A; Hernandez-Duque, Guillermo; Mitchell, Ralph

2006-01-01

Biodeterioration of archaeological sites and historic buildings is a major concern for conservators, archaeologists, and scientists involved in preservation of the world's cultural heritage. The Maya archaeological sites in southern Mexico, some of the most important cultural artifacts in the Western Hemisphere, are constructed of limestone. High temperature and humidity have resulted in substantial microbial growth on stone surfaces at many of the sites. Despite the porous nature of limestone and the common occurrence of endolithic microorganisms in many habitats, little is known about the microbial flora living inside the stone. We found a large endolithic bacterial community in limestone from the interior of the Maya archaeological site Ek' Balam. Analysis of 16S rDNA clones demonstrated disparate communities (endolithic: >80% Actinobacteria, Acidobacteria, and Low GC Firmicutes; epilithic: >50% Proteobacteria). The presence of differing epilithic and endolithic bacterial communities may be a significant factor for conservation of stone cultural heritage materials and quantitative prediction of carbonate weathering.

In vitro CT evaluation of intrahepatic stones: correlation with chemical composition

International Nuclear Information System (INIS)

Kim, Young Jun; Han, Joon Koo; Jeong, Jun Yong; Lee, Kyoung Ho; Kim, Se Hyung; Kim, Young Il; Lee, Jeong Min; Choi, Byung Ihn; Park, Youn-Chan; Kim, Sun-Whe

2005-01-01

Objective: To describe in vitro CT features of intrahepatic stones and to correlate CT attenuation with chemical composition. Materials and methods: Of the patients who underwent choledochoscopic intrahepatic stone removal between 1998 and 2001, 54 patients with stones larger than 3 mm were enrolled in this study. In each case, a chemical compositional analysis was performed to determine calcium, cholesterol, total bilirubin, and inorganic phosphorus compositions. The three largest stones obtained from each patient were imaged by CT. CT attenuation numbers were measured in the center images of each stone by drawing free-hand region of interest (ROI). The measured CT attenuation numbers were correlated with their chemical composition. Also, CT attenuation numbers of stones were compared with that of the liver on non-contrast CT (50-70 HU). Results: Stone size ranged from 3.1 to 10.5 mm (mean ± S.D.: 6.0 ± 1.4). The CT attenuation numbers (HU) of stones ranged from 36.4 to 410.19 (mean ± S.D.: 94.6 ± 49.9). CT numbers of stones were below 70 HU in 11 patients (20.4%), and below 90 HU in 33 patients (59.3%). The chemical analysis data of the stones were as follows: calcium (0.5-6.5 wt.%; mean ± S.D., 2.6 ± 1.4), total bilirubin (0.45-24.4 wt.%; 13.1 ± 6.2), cholesterol (5.4-73.9 wt.%; 29.3 ± 17.4), phosphorus (0.1-1.2 wt.%; 0.6 ± 0.3), and non-soluble residue (17.6-85.4 wt.%; 57.0 ± 22.6). There was a weak but significant correlation between calcium composition and CT attenuation (r = 0.38, P 0.01; total bilirubin, r = 0.05, P > 0.01; phosphorus, r = 0.01, P > 0.01). Conclusion: On non-contrast CT, intrahepatic stones would not be hyperattenuating with respect to liver parenchyma in about one fifth of patients. The CT attenuation of stones correlates with calcium and does not correlate with any other chemical composition

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

The study on the factors for detection of renal stone on ultrasound

International Nuclear Information System (INIS)

Sim, Hyun Sun; Jung, Hong Ryang; Lim, Cheong Hwan

2006-01-01

Renal stones are common and typically arise within the collecting system. The renal sinus are contains the collection system, the renal vessels, lymphatcs, fat, and fibrous tissue. Because of the compression of all the large echoes in signal processing, the echo from the renal stone generally cannot be distinguished from large echoes emanating from normal structures of the renal sinus. Use of ultrasonography has been difficult for detecting small renal stone without posterior shadowing and chemical composition of stone. The aim of study was measuring for posterior acoustic shadowing to a stone for various scan parameter and it examines a help in renal stone diagnosis. The stone was place on sponge examined in a water bath with a 3.5 MHz or 7.5 HMz transducer (LOGIQ 400, USA). First, tested a variety of gain. Second, tested a variety of dynamic range. Third, tested a variety of focal zone. Fourth, measuring of the echo level for low and high frequency for depth. 1) Average echo level was 98 for low total gain (10 dB) and was 142 for high total gain (40 dB). Posterior acoustic shadowing of renal stone was clear for low gain. 2) Average echo level was 129 for low dynamic range (42 dB) and was 101 for high dynamic range (72 dB). Posterior acoustic shadowing of renal stone was clear for high dynamic range. 3) When stone is in focal zone of transducer, definite posterior acoustic shadow is identified. 4) Stone was clear appeared for high frequency (7.5 MHz) than low frequency (3.5 MHz) and it is not distorted. The demonstration of an posterior acoustic shadow of renal stone dependents on several technical factors such as gain, dynamic range, focus, and frequency. This various factors are a help in renal stone diagnosis

21 CFR 876.4650 - Water jet renal stone dislodger system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Water jet renal stone dislodger system. 876.4650... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4650 Water jet renal stone dislodger system. (a) Identification. A water jet renal stone dislodger system is a device used to...

The Incidence of Complications in Single-stage Endoscopic Stone Removal for Patients with Common Bile Duct Stones: A Propensity Score Analysis.

Science.gov (United States)

Saito, Hirokazu; Kadono, Yoshihiro; Kamikawa, Kentaro; Urata, Atsushi; Imamura, Haruo; Matsushita, Ikuo; Kakuma, Tatsuyuki; Tada, Shuji

2018-02-15

Objective Single-stage endoscopic stone removal for choledocholithiasis is an advantageous approach because it is associated with a shorter hospital stay; however, few studies have reported the incidence of complications related to this procedure in detail. The aim of this study was to examine the incidence of complications and efficacy of this procedure. Methods This retrospective study investigated the incidence of complications in 345 patients with naive papilla who underwent therapeutic endoscopic retrograde cholangiopancreatography (ERCP) for choledocholithiasis at three institutions between April 2014 and March 2016 by a propensity score analysis. The efficacy of single-stage endoscopic stone removal was assessed based on a hospital stay of within 7 days and the number of ERCP attempts. Results Among 114 patients who underwent single-stage endoscopic stone removal, 15 patients (13.2%) experienced complications. Among the remaining 231 patients in the two-stage endoscopic stone removal group, complications were observed in 17 patients (7.4%). The propensity score analysis, which was adjusted for confounding factors, revealed that single-stage endoscopic stone removal was not a significant risk factor for complications (p=0.52). In patients in whom >10 min was required for deep cannulation, single-stage endoscopic stone removal was not a significant risk factor for complications in the propensity score analysis (p=0.37). In the single-stage group, the proportion of patients with a hospital stay of within 7 days was significantly higher and the number of ERCP attempts was significantly lower in comparison to the two-stage group (p <0.0001 and <0.0001, respectively). Conclusion Single-stage endoscopic stone removal did not increase the incidence of complications associated with ERCP and was effective for reducing the hospital stay and the number of ERCP attempts.

Accelerated weathering of limestone for CO2 mitigation: Opportunities for the stone and cement industries

Science.gov (United States)

Langer, William H.; San, Juan A.; Rau, Greg H.; Caldeira, Ken

2009-01-01

Large amounts of limestone fines co-produced during the processing of crushed limestone may be useful in the sequestration of carbon dioxide (CO2). Accelerated weathering of limestone (AWL) is proposed as a low-tech method to capture and sequester CO2 from fossil fuel-fired power plants and other point sources such as cement manufacturing. AWL reactants are readily available, inexpensive and environmentally benign. Waste CO2 is hydrated with water to produce carbonic acid. This reacts with and is neutralized by limestone fines, thus converting CO2 gas to dissolved calcium bicarbonate.

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...

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.

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.

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.

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.

Effect of blind treatment on stone disease.

Science.gov (United States)

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

2010-06-01

Most of the drugs administered to stone patients appear to be inappropriate and doing more harm than good to the patients. The objective of this paper is to identify the prevalence of blind chemotherapy among the stone patients and find out the real indication for the drugs administered. Patients who attended the stone clinic for the first time were interviewed to find out what drugs they had been taking before the attendance at the stone clinic. 350 patients consuming specific drugs relevant to stone formation at least for a period of 15 days were selected for a detailed assessment. The type of drug consumed, the dose, the duration, the side effects, compliance rate and effect on stone disease were assessed. The biochemical profile of the patients was assessed to identify the role of the therapeutic modalities utilised. Conclusions regarding the utility of drugs in the process of stone formation were made. The values were compared with those of patients not on medication and considering laboratory standards. Of the 350 patients studied, 96 patients were consuming potassium citrate in different doses, 50 were consuming allopurinol, 44 cystone, 27 potassium citrate + magnesium, 25 calcury, 24 rowatinex, 21 ayurvedic drugs, 17 dystone, 17 homeopathic medicines and 17 other drugs. The longest duration of compliance was for cystone-2.5 years. All other drugs were stopped by the patients themselves due to recurrence of symptoms. As much as 93% of the patients did not feel that there was any significant relief of symptoms. The side effects which prompted the patients to stop medicine were gastro intestinal upset, particularly with potassium citrate, rowatinex and potassium citrate + magnesium combination. The relevant biochemical changes noted were increased urinary citrate levels in patients consuming potassium citrate alone or in combination with magnesium. Serum uric acid was within normal limits in patients consuming allopurinol. Urine uric acid levels were also

Population-based estimate of urinary stones from Ballabgarh, northern India.

Science.gov (United States)

Lohiya, Ayush; Kant, Shashi; Kapil, Arti; Gupta, Sanjeev Kumar; Misra, Puneet; Rai, Sanjay K

2017-01-01

Stones in the urinary tract are a common condition but there is paucity of data on their population-based estimates in India. We describe our findings of the burden of urinary stones during a cross-sectional study with another primary goal. We conducted the study at Ballabgarh Health and Demographic Surveillance System, Haryana, among residents aged 18 years or above. We used simple random sampling to enrol participants. Self-reported history of urinary stones was elicited through an interview schedule. Results of the descriptive analysis were described as proportions with 95% confidence intervals (CI) or as mean wherever applicable. Bivariate analysis was done using t-test and chi-square test as applicable. The response rate for our study was 86.6%; lifetime prevalence (95% CI) of urinary stones was 7.9% (5.7, 10.8). In a majority of participants, urinary stones were diagnosed at an age of 20-40 years (55.9%), mostly by an ultrasonography examination (94.1%). A high burden of urinary stones is indicated in the working-age population in northern India at the community level. Untreated urinary stones can lead to an acute emergency (colic) or may have long-term adverse consequences, e.g. hydronephrosis, which have implications for the healthcare delivery system.

The History of Urinary Stones: In Parallel with Civilization

Directory of Open Access Journals (Sweden)

Ahmet Tefekli

2013-01-01

Full Text Available The roots of modern science and history of urinary stone disease go back to the Ancient Egyptians and Mesopotamia. Hippocrates defined the symptoms of bladder stones. The first recorded details of “perineal lithotomy” were those of Cornelius Celsus. Ancient Arabic medicine was based mainly on classical Greco-Roman works. Interestingly, the Fourth Lateran Council in 1215 forbade physicians from performing surgical procedures, as contact with blood or body fluids was viewed as contaminating to men. With Renaissance new procedures could be tried on criminals. The first recorded suprapubic lithotomy was carried out by Pierre Franco in 1561. In 1874, Bigelow developed a lithotrite, which was introduced into the bladder under anaesthesia (called as “litholopaxy”. Young was the first to report ureteroscopy (1929. With advances in intracorporeal lithotripsy techniques, ureteroscopy became the treatment of choice for ureteric stones. In 1976, Fernstrom and Johannson established percutaneous access to remove a renal stone. However, with the introduction of the first extracorporeal shock wave machine in 1980, a dramatic change in stone management was observed. Civilization in parallel with scientific developments has brought us to a point where we try not to “cut” our patients for stone disease, as Hippocrates admonishes, but rather manage them with minimal invasive alternatives.

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.

Geochemical behavior under tropical weathering of the Barama-Mazaruni greenstone belt at Omai gold mine, Guiana Shield

Energy Technology Data Exchange (ETDEWEB)

Voicu, G. [Universite du Quebec a Montreal (Canada). Dept. des Sciences de la Terre et de l' Atmosphere; Omai Gold Mines, Georgetown (Guyana); Bardoux, M. [Universite du Quebec a Montreal (Canada). Dept. des Sciences de la Terre et de l' Atmosphere

2002-07-01

Mineralogical, petrographical, and geochemical studies of the weathering profile have been carried out at Omai Au mine, Guyana. The area is underlain by felsic to mafic volcanic and sedimentary rocks of the Barama-Mazaruni Supergroup, part of the Paleoproterozoic greenstone belts of the Guiana Shield. Tropical rainy climate has favoured extensive lateritization processes and formation of a deeply weathered regolith. The top of the weathering profile consists of lateritic gravel or is masked by the Pleistocene continental-deltaic Berbice Formation. Mineralogical composition of regolith consists mainly of kaolinite, goethite and quark, and subordinately sericite, feldspar, hematite, pyrite, smectite, heavy minerals, and uncommon mineral phases (nacrite, ephesite, corrensite, guyanaite). A specific feature of the weathering profile at Omai is the preservation of fresh hydrothermal pyrite in the saprolith horizon. Chemical changes during the weathering processes depend on various physicochemical and structural parameters. Consequently, the depth should not be the principal criterion for comparison purposes of the geochemical behavior within the weathering profile, but rather an index that measures the degree of supergene alteration that has affected each analyzed sample, independently of the depth of sampling. Thus, the mineralogical index of alteration (MIA) can provide more accurate information about the behavior of major and trace elements in regolith as opposed to unweathered bedrock. It can also aid in establishing a quantitative relationship between intensity of weathering and mobility (leaching or accumulation) of each element in each analyzed sample. At Omai, some major and trace elements that are commonly considered as immobile (ex: TiO{sub 2}, Zr, etc.) during weathering could become mobile in several rock types and cannot be used to calculate the mass and volume balance. In addition, due to higher ''immobile element'' ratios, the

Transcystic duct treatment of common bile duct stones

International Nuclear Information System (INIS)

Amberg, J.R.; Chun, G.

1981-01-01

Successful removal of 2 retained common bile duct stones following cholecystostomy is described. With the use of the steerable catheter and the wire basket, one stone was crushed and the second was extracted in retrograde fashion through the cystic duct and gallbladder. (orig.)

Ultrasonographic diagnosis of ureteral stones: Accuracy and factors influencing on diagnostic sensitivity

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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

Strength Improvement of Clay Soil by Using Stone Powder

OpenAIRE

Ahmed Sameer Abdulrasool

2015-01-01

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 re...

Management of bladder stones: the move towards non-invasive treatment

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Isaac A. Deswanto

2017-08-01

Full Text Available Background: Bladder stone accounts for 5% of all cases of urolithiasis. Bladder stones management has evolved over the last decades from open bladder surgery (sectio alta to intracorporeal cystholithotripsy as well as extracorporeal shock wave lithotripsy (ESWL. ESWL presents to be a promising modality in the management of bladder calculi due to its simplicity and well tolerability. This study is thus conducted to present data on the safety and effectiveness of ESWL in the management of bladder stone patients.Methods: This is a retrospective study evaluating the medical records of 92 bladder calculi patients admitted to Cipto Mangunkusumo General Hospital (RSCM from January 2011 to April 2015. Patient’s age, gender, type of stone and procedure being done, status of stone disintegration, length of hospital stay, and any complications that may occur are noted down and statistically analyzed using SPSS v. 20.Results: Majority of the patients underwent ESWL (49 out of 92, 53.3%. The stone free rates for ESWL, intracorporeal lithotripsy, and sectio alta are 93.9%, 97.0% and 100% respectively. One patient had to repeat ESWL. The ESWL group had the smallest stone size average compared to the intracorporeal lithotripsy and section alta group (2.5 cm±2.0 cm vs 4.8 cm±3.7 cm vs 7.4 cm±5.4 cm respectively. The ESWL sessions were conducted in the outpatient clinic, and thus no hospital stay was required.Conclusion: ESWL can be suggested as an effective non-invasive approach in the disintegration of bladder stone of ≤25 mm with a promisingly high stone-free rate (93.9% Furthermore, ESWL can be performed on an outpatient basis with minimal complications.

A neural network - based algorithm for predicting stone - free status after ESWL therapy.

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Seckiner, Ilker; Seckiner, Serap; Sen, Haluk; Bayrak, Omer; Dogan, Kazim; Erturhan, Sakip

2017-01-01

The prototype artificial neural network (ANN) model was developed using data from patients with renal stone, in order to predict stone-free status and to help in planning treatment with Extracorporeal Shock Wave Lithotripsy (ESWL) for kidney stones. Data were collected from the 203 patients including gender, single or multiple nature of the stone, location of the stone, infundibulopelvic angle primary or secondary nature of the stone, status of hydronephrosis, stone size after ESWL, age, size, skin to stone distance, stone density and creatinine, for eleven variables. Regression analysis and the ANN method were applied to predict treatment success using the same series of data. Subsequently, patients were divided into three groups by neural network software, in order to implement the ANN: training group (n=139), validation group (n=32), and the test group (n=32). ANN analysis demonstrated that the prediction accuracy of the stone-free rate was 99.25% in the training group, 85.48% in the validation group, and 88.70% in the test group. Successful results were obtained to predict the stone-free rate, with the help of the ANN model designed by using a series of data collected from real patients in whom ESWL was implemented to help in planning treatment for kidney stones. Copyright® by the International Brazilian Journal of Urology.

A radiologic study of salivary stones

International Nuclear Information System (INIS)

Cho, Hyo Suck; Ahn, Hyung Kyu

1986-01-01

The author examined fifty cases of sialolithiasis diagnosed in the Dept. of Oral Radiology in SNUH by conventional radiography and sialography, and patient's age, sex, location, radiodensity, numbers, shapes, and relation with ducts a nd parenchymas. The results of this study were as follows: 1. The average age of patients was 38.6 years in submandibular sialolithiasis, and 39.2 years in parotid sialolithiasis. 2. There was slightly higher incidence in males (58.0%) than in females (42.0%). 3. Salivary stones were found to be much more in the submandibular gland and duct (82.0%) than in the parotid gland and duct (18.0%). 4. Of 62 submandibular salivary stones, 33 (53.2%) occurred in the main duct, 25 (40.3%) occurred in the hilum, and 4 (6.5%) occurred in the parenchyma. Of 18 parotid salivary stones, 9(50.0%) occurred in the main duct, 5(27.8%) occurred in the parenchyma, and 4 (22 .2%) occurred in the hilum. 5. Of the submandibular salivary stones, the number of radiopaque type was 45 (75.8%), and the number of radiolucent type was 17 (24.2%). Of the parotid salivary stones, the number of radiopaque type was 12 (66.7%), and the number of radiolucent type was 6 (33.3%). 6. The single type was 30 cases (73.2%) in submandibular gland, 6 cases (66.7%) in parotid gland, and the multiple type was 11 cases (26.8%) in submandibular grand, and 3 cases (33. 3%) in parotid gland. 7. Round shape was 35 cases (43.8%), ovoid shape was 22 cases (27.5%), irregular shape was 17 cases (21.3%), and cylindrical shape was 6 cases (7.5%).

FIELD-SCALE LEACHING OF ARSENIC, CHROMIUM AND COPPER FROM WEATHERED TREATED WOOD

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Hasan, A. Rasem; Hu, Ligang; Solo-Gabriele, Helena M.; Fieber, Lynne; Cai, Yong; Townsend, Timothy G.

2010-01-01

Earlier studies documented the loss of wood preservatives from new wood. The objective of this study was to evaluate losses from weathered treated wood under field conditions by collecting rainfall leachate from 5 different wood types, all with a surface area of 0.21 m2. Wood samples included weathered chromate copper arsenate (CCA) treated wood at low (2.7 kg/m3), medium (4.8 kg/m3) and high (35.4 kg/m3) retention levels, new alkaline copper quat (ACQ) treated wood (1.1 kg/m3 as CuO) and new untreated wood. Arsenic was found to leach at a higher rate (100 mg in 1 year for low retention) than chromium and copper (leached at the highest rate from the ACQ sample (670 mg). Overall results suggest that metals’ leaching is a continuous process driven by rainfall, and that the mechanism of release from the wood matrix changes as wood weathers. PMID:20053493

Anatomical factors predicting lower calyceal stone clearance after extracorporeal shockwave lithotripsy

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M. Khan

2016-06-01

Conclusions: This study shows that lower infundibular length and width are significant anatomical factors in determining stone clearance following ESWL treatment of lower calyceal stones and these should be assessed before planning the treatment for lower calyceal stones.

Detection of endolithic spatial distribution in marble stone.

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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.

Absolute Hounsfield unit measurement on noncontrast computed tomography cannot accurately predict struvite stone composition.

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Marchini, Giovanni Scala; Gebreselassie, Surafel; Liu, Xiaobo; Pynadath, Cindy; Snyder, Grace; Monga, Manoj

2013-02-01

The purpose of our study was to determine, in vivo, whether single-energy noncontrast computed tomography (NCCT) can accurately predict the presence/percentage of struvite stone composition. We retrospectively searched for all patients with struvite components on stone composition analysis between January 2008 and March 2012. Inclusion criteria were NCCT prior to stone analysis and stone size ≥4 mm. A single urologist, blinded to stone composition, reviewed all NCCT to acquire stone location, dimensions, and Hounsfield unit (HU). HU density (HUD) was calculated by dividing mean HU by the stone's largest transverse diameter. Stone analysis was performed via Fourier transform infrared spectrometry. Independent sample Student's t-test and analysis of variance (ANOVA) were used to compare HU/HUD among groups. Spearman's correlation test was used to determine the correlation between HU and stone size and also HU/HUD to % of each component within the stone. Significance was considered if pR=0.017; p=0.912) and negative with HUD (R=-0.20; p=0.898). Overall, 3 (6.8%) had stones (n=5) with other miscellaneous stones (n=39), no difference was found for HU (p=0.09) but HUD was significantly lower for pure stones (27.9±23.6 v 72.5±55.9, respectively; p=0.006). Again, significant overlaps were seen. Pure struvite stones have significantly lower HUD than mixed struvite stones, but overlap exists. A low HUD may increase the suspicion for a pure struvite calculus.

Childhood bladder stones-an endemic disease of developing countries

International Nuclear Information System (INIS)

Lal, B.

2015-01-01

Bladder calculi are one of the commonest health problems in young children especially in rural and underprivileged areas. Methods: All children of bladder stones operated at District Headquarter Hospital Mithi from July 2009 to June 2012 were included in this cross-sectional study. Data was collected regarding age, sex, address (rural or urban), body weight, duration of breast feeding, weaning, detailed dietary history regarding milk type, volume, amount of water intake, recurrent diarrhoea, urinary tract infection (UTI), family history, and socioeconomic history. Urine analysis, complete blood count (CBC), renal function, ultra sound abdomen, X-ray kidney, ureter, and bladder (KUB) was done in all patients. All patients had cystolithotomy and were followed up till complete recovery. Results: A total of 113 children (97 males and 16 females) operated at District Headquarter Hospital Mithi Tharparker were included in study. All patients belonged to local desert areas of Tharparker. Age ranged from 18 months to 14 year (mean age 8.6 year). Most frequent symptom was difficulty in micturition in 76 (67.25%) patients, urinary retention in 18 (15.9%) and stone with pyuria and fever in 12 (10.6%) patients. Recurrent episodes of diarrhoea (more than 3 episodes per year) in 73(65%) patients, recurrent UTI in 51 (45.6%), family history of stone disease in 6 (5%) and associated rectal prolapse in 3(2.6%) patients. On x-ray KUB 111 (98%) patients had single stone in bladder, 2 (2%) had multiple stones and an associated renal and ureteric stone in 5 (4.5%). Mild anaemia (Hb 7-10 gm%) was seen in 35 (39.55%) patients, moderate anaemia (Hb 5-7 gm %) was seen in 21(24%) and severe anaemia (Hb less than 5 gm%) was seen in 14 (16%) patients. All patients had open cystolithotomy for removal of stones under general anaesthesia. Conclusion: Bladder stones are public health problem. Majority of affected patients were less than 5 years old. Low protein diet, dehydration, use of goat milk

Patients' selection for treatment of caliceal diverticular stones with extracorporeal shock wave lithotripsy

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Lee, Won Hong; Lee, Hee Jeong; Son, Soon Yong; Kang, Seong Ho; Cho, Cheong Chan; Ryu, Meung Sun [AMC, Seoul (Korea, Republic of); Kim, Seung Kook [Kwang-Ju Health College, Kwang-Ju (Korea, Republic of)

2001-06-01

Symptoms of caliceal diverticular stones are commonly associated with pain, recurrent urinary tract infection and hematuria. The aim of this study is to select the proper patient for the application of more successful extracorporeal shock wave lithotripsy(ESWL) as a treatment of caliceal diverticular stone. 16 patients with caliceal diverticular stones were treated with ESWL, and all patients had single caliceal diverticulum. The diagnosis of caliceal diverticulum with stones was made by intraveneous pyelography to all patients. On these intravenous pyelogram, we also classified diverticular type, whether the diverticular neck is connected with urinary tract patently, diverticular site and stone number and size. All patients were followed after ESWL by plain film of the kidneys, ureters and bladder and interviewed. Of all patients 44% was shown stone-free completely, also 83% was rendered symptom-free. All patients whose diverticular neck connected with urinary tract patently on the intraveneous pyelogram became stone-free. Of solitary stone 60% and multiple stones (more than 2) 17% became symptom-free. The patients with infection before ESWL 75% had residual stones, of these patients 33% had slightly flank pain, and 25% of patients with stones recurred become stone-free. We propose that more successful ESWL for patients with caliceal diverticular stones select satisfactory patients including that the diverticular neck is connected with urinary tract patently, solitary stone and no infection simultaneously.

[Solitary stones of the lower renal calyx: how to treat?

Science.gov (United States)

Martov, A G; Ergakov, D V; Andronov, A S; Dutov, S V; Takhaev, R A; Kil'chukov, Z I; Moskalenko, S A

2017-06-01

The choice of treatment for the stones of the lower renal calyx is one of the challenging issues of modern urology. The aim of this retrospective and prospective study was to investigate the clinical effectiveness and safety of 3 modern minimally invasive techniques for treating renal stones: percutaneous (PNL) and transurethral (TNL) nephrolithotripsy and extracorporeal shock wave lithotripsy (ESWL) in patients with solitary lower calyx stones sized from 10 to 15 mm. The study included 136 patients with symptomatic stones of the lower calyces, who underwent ESWL, PNL and TNL from November 2010 to the present day. The criteria for inclusion in the study were: the presence of a solitary stone of the lower calyx, the stone size of 10 mm to 15 mm, the performance of the classical (standard) PNL in the prone position (puncture access 28-30 Fr) and the follow-up examination at 3 months after the operation. Forty-six patients underwent ESWL, 49 - PNL, and 41 - TNL. Postoperative follow-up was done at 3 months and included a plain radiography, ultrasound and non-contrast-enhanced computed tomography. The stone free rate (SFR) was used as a criterion for the effectiveness of the intervention, where the stone size of 3 mm was taken as the upper limit for the possible presence of fragments. Besides, the rate of repeat interventions, complications and subjective assessment of patients treatment satisfaction (0 to 10) by using visual analogue scale (VAS) were investigated. The effectiveness analysis of the three methods for treating the lower calyx stones sized 10-15 mm showed that PNL was no more effective than TNL (SFR 95.9% and 85.4%, respectively), but both methods were significantly more effective than ESWL (SFR 69.5%). 29.3% of patients who underwent TNL required repeat interventions (TNL or ESWL), while among those treated with ESWL, 45.6% required repeat ESWL sessions. PNL resulted in stone clearance in one stage. Postoperative inflammatory complications were most

Safety and efficacy of staged retrograde intrarenal surgery for large stone burden of renal stones in selected patients: A single-center experience

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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%.

A small stone column of the altar screen from the treasures of St Archangel Michael's monastery in Prevlaka

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Crnčević Dejan

2013-01-01

it. The material, size, characteristic shape, together with its special personal details, such as the channel around the whole height of its left lateral side, as well as the shallow hole on its upper surface, without doubt show that it was one of the original stone columns of a particular stone altar screen. Analysis of the motif's source, decorative forms, and the quality of its carving confirm that this segment of the altar screen represents one more parts of the same sculptors' workshop which produced one preserved part of the stone altar screen of St Triphon in Kotor, which received the same decorative and sculptural treatment, also undoubtedly originating from no before than the 11th century. The possibility of completely resolving the dilemma of which sacred complex the column originally belonged to will only be resolved when archaeological excavation and investigation of the site of the monastery of St Archangel Michael in Prevlaka, in whose treasury it stands, together with the neighbouring island of St Gavrilo, on which the pillar was found, takes place. The possibility of precisely dating this stone altar screen will only occur with the expected full understanding of the whole altar screen of the Cathedral church of St Triphon in Kotor. However, this segment of the stone altar screen also represents a reason to better comprehend the morphological characteristics and variety of stylistic expression present and specifically applied in the decorative elements of early-medieval sculpture on the southern-eastern Adriatic coast.

Mini vs standard percutaneous nephrolithotomy for renal stones: a comparative study.

Science.gov (United States)

ElSheemy, Mohammed S; Elmarakbi, Akram A; Hytham, Mohammed; Ibrahim, Hamdy; Khadgi, Sanjay; Al-Kandari, Ahmed M

2018-03-16

To compare the outcome of mini-percutaneous nephrolithotomy (Mini-PNL) versus standard-PNL for renal stones. Retrospective study was performed between March 2010 and May 2013 for patients treated by Mini-PNL or standard-PNL through 18 and 30 Fr tracts, respectively, using pneumatic lithotripsy. Semirigid ureteroscope (8.5/11.5 Fr) was used for Mini-PNL and 24 Fr nephroscope for standard-PNL. Both groups were compared in stone free rate(SFR), complications and operative time using Student-t, Mann-Whitney, Chi square or Fisher's exact tests as appropriate in addition to logistic regression analysis. P PNL (378) and standard-PNL (151) were nearly comparable in patients and stones criteria including stone burden (3.77 ± 2.21 vs 3.77 ± 2.43 cm 2 ; respectively). There was no significant difference in number of tracts or supracostal puncture. Mini-PNL had longer operative time (68.6 ± 29.09 vs 60.49 ± 11.38 min; p = 0.434), significantly shorter hospital stay (2.43 ± 1.46 vs 4.29 ± 1.28 days) and significantly higher rate of tubeless PNL (75.1 vs 4.6%). Complications were significantly higher in standard-PNL (7.9 vs 20.5%; p PNL (89.9 vs 96%; p = 0.022). This significant difference was found with multiple stones and large stone burden (> 2 cm 2 ), but the SFR was comparable between both groups with single stone or stone burden ≤ 2 cm. Logistic regression analysis confirmed significantly higher complications and SFR with standard-PNL but with significantly shorter operative time. Mini-PNL has significantly lower SFR when compared to standard-PNL (but clinically comparable) with markedly reduced complications and hospital stay. Most of cases can be performed tubeless. The significant difference in SFR was found with multiple stones or large stone burden (> 2 cm 2 ), but not with single stones or stone burden ≤ 2 cm 2 .

Bariatric Surgery and Urinary Stone Disease

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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.

Utility of Flexible Ureterorenoscopy and Laser Lithotripsy in the Treatment of Multiple Intrarenal Stones

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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.

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)

Automated visual inspection for polished stone manufacture

Science.gov (United States)

Smith, Melvyn L.; Smith, Lyndon N.

2003-05-01

Increased globalisation of the ornamental stone market has lead to increased competition and more rigorous product quality requirements. As such, there are strong motivators to introduce new, more effective, inspection technologies that will help enable stone processors to reduce costs, improve quality and improve productivity. Natural stone surfaces may contain a mixture of complex two-dimensional (2D) patterns and three-dimensional (3D) features. The challenge in terms of automated inspection is to develop systems able to reliably identify 3D topographic defects, either naturally occurring or resulting from polishing, in the presence of concomitant complex 2D stochastic colour patterns. The resulting real-time analysis of the defects may be used in adaptive process control, in order to avoid the wasteful production of defective product. An innovative approach, using structured light and based upon an adaptation of the photometric stereo method, has been pioneered and developed at UWE to isolate and characterize mixed 2D and 3D surface features. The method is able to undertake tasks considered beyond the capabilities of existing surface inspection techniques. The approach has been successfully applied to real stone samples, and a selection of experimental results is presented.

Bone Genes in the Kidney of Stone Formers

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