Natural Cr3+-rich ettringite: occurrence, properties, and crystal structure

Science.gov (United States)

Seryotkin, Yurii V.; Sokol, Ella V.; Kokh, Svetlana N.; Murashko, Mikhail N.

2017-08-01

Cr3+-rich ettringite with Cr3+→Al substitution and Cr/(Cr + Al) ratios up to 0.40-0.50 was found in mineral assemblages of the Ma'aleh Adumim area of Mottled Zone (Judean Desert). The Cr3+-rich compositions were the latest in the thaumasite → ettringite-thaumasite solid solution → ettringite → ettringite-bentorite solid solution series. The mineral-forming solution was enriched in Cr3+ and had a pH buffered by afwillite at 11-12. Chromium was inherited from larnite rocks produced by high-temperature combustion metamorphic alteration of bioproductive calcareous sediments. The Cr/(Cr + Al) ratios are within 0.10-0.15 in most of the analysed crystals. This degree of substitution imparts pink colouration to the crystals, but does not affect their habit (a combination of monohedra and a prism). The habit changes to pyramid faces in coarse and later Cr3+-bearing crystals as Cr/(Cr + Al) ratios increase abruptly to 0.40-0.50. Single-crystal XRD analysis of one Cr-free and two Cr3+-rich samples and their structure determination and refinement indicate that the Cr-rich crystals (with Cr/(Cr + Al) to 0.3) preserve the symmetry and metrics of ettringite. The Ca-O bonding network undergoes differentiation with increase of Cr3+ concentration at octahedral M sites. The compression of Ca2 and expansion of Ca1 polyhedra sub-networks correlates with the degree of Cr3+→Al substitution.

Compositional and structural variabilities of Mg-rich iron oxide spinels from tuffite

Directory of Open Access Journals (Sweden)

W. N. Mussel

1999-12-01

Full Text Available Maghemite (γFe2O3 from tuffite is exceptionally rich in Mg, relatively to most of those reportedly found in other mafic lithosystems. To investigate in detail the compositional and structural variabilities of this natural magnetic iron oxide, sets of crystals were isolated from samples collected at different positions in a tuffite weathering mantle. These sets of crystal were individually powdered and studied by X-ray diffractometry, Mössbauer spectroscopy, magnetization measurements and chemical analysis. Lattice parameter of the cubic cell (a0 was found to vary from 0.834(1 to 0.8412(1 nm. Lower a0-values are characteristic of maghemite whereas higher ones are related to a magnetite precursor. FeO content ranges up to 17 mass % and spontaneous magnetization ranges from 8 to 32 J T-1 kg-1. Zero-field room temperature Mössbauer spectra are rather complex, indicating that the hyperfine field distributions due to Fe3+ and mixed valence Fe3+/2+ overlap. The structural variabilities of the (Mg, Ti-rich iron oxide spinels is essentially related to the range of chemical composition of its precursor (Mg, Ti-rich magnetite, and probably to the extent to which it has been oxidized during transformation in soil.

Diffusion tractography and graph theory analysis reveal the disrupted rich-club organization of white matter structural networks in early Tourette Syndrome children

Science.gov (United States)

Wen, Hongwei; Liu, Yue; Wang, Shengpei; Zhang, Jishui; Peng, Yun; He, Huiguang

2017-03-01

Tourette syndrome (TS) is a childhood-onset neurobehavioral disorder. At present, the topological disruptions of the whole brain white matter (WM) structural networks remain poorly understood in TS children. Considering the unique position of the topologically central role of densely interconnected brain hubs, namely the rich club regions, therefore, we aimed to investigate whether the rich club regions and their related connections would be particularly vulnerable in early TS children. In our study, we used diffusion tractography and graph theoretical analyses to explore the rich club structures in 44 TS children and 48 healthy children. The structural networks of TS children exhibited significantly increased normalized rich club coefficient, suggesting that TS is characterized by increased structural integrity of this centrally embedded rich club backbone, potentially resulting in increased global communication capacity. In addition, TS children showed a reorganization of rich club regions, as well as significantly increased density and decreased number in feeder connections. Furthermore, the increased rich club coefficients and feeder connections density of TS children were significantly positively correlated to tic severity, indicating that TS may be characterized by a selective alteration of the structural connectivity of the rich club regions, tending to have higher bridging with non-rich club regions, which may increase the integration among tic-related brain circuits with more excitability but less inhibition for information exchanges between highly centered brain regions and peripheral areas. In all, our results suggest the disrupted rich club organization in early TS children and provide structural insights into the brain networks.

EGCG Inhibited Lipofuscin Formation Based on Intercepting Amyloidogenic β-Sheet-Rich Structure Conversion.

Directory of Open Access Journals (Sweden)

Shuxian Cai

Full Text Available Lipofuscin (LF is formed during lipid peroxidation and sugar glycosylation by carbonyl-amino crosslinks with biomacrolecules, and accumulates slowly within postmitotic cells. The environmental pollution, modern dietary culture and lifestyle changes have been found to be the major sources of reactive carbonyl compounds in vivo. Irreversible carbonyl-amino crosslinks induced by carbonyl stress are essentially toxiferous for aging-related functional losses in modern society. Results show that (--epigallocatechin gallate (EGCG, the main polyphenol in green tea, can neutralize the carbonyl-amino cross-linking reaction and inhibit LF formation, but the underlying mechanism is unknown.We explored the mechanism of the neutralization process from protein, cell, and animal levels using spectrofluorometry, infrared spectroscopy, conformation antibodies, and electron microscopy. LF demonstrated an amyloidogenic β-sheet-rich with antiparallel structure, which accelerated the carbonyl-amino crosslinks formation and disrupted proteolysis in both PC12 cells and D-galactose (D-gal-induced brain aging mice models. Additionally, EGCG effectively inhibited the formation of the amyloidogenic β-sheet-rich structure of LF, and prevented its conversion into toxic and on-pathway aggregation intermediates, thereby cutting off the carbonyl-amino crosslinks.Our study indicated that the amyloidogenic β-sheet structure of LF may be the core driving force for carbonyl-amino crosslinks further formation, which mediates the formation of amyloid fibrils from native state of biomacrolecules. That EGCG exhibits anti-amyloidogenic β-sheet-rich structure properties to prevent the LF formation represents a novel strategy to impede the development of degenerative processes caused by ageing or stress-induced premature senescence in modern environments.

Species richness and soil properties in Pinus ponderosa forests: A structural equation modeling analysis

Science.gov (United States)

Laughlin, D.C.; Abella, S.R.; Covington, W.W.; Grace, J.B.

2007-01-01

Question: How are the effects of mineral soil properties on understory plant species richness propagated through a network of processes involving the forest overstory, soil organic matter, soil nitrogen, and understory plant abundance? Location: North-central Arizona, USA. Methods: We sampled 75 0.05-ha plots across a broad soil gradient in a Pinus ponderosa (ponderosa pine) forest ecosystem. We evaluated multivariate models of plant species richness using structural equation modeling. Results: Richness was highest at intermediate levels of understory plant cover, suggesting that both colonization success and competitive exclusion can limit richness in this system. We did not detect a reciprocal positive effect of richness on plant cover. Richness was strongly related to soil nitrogen in the model, with evidence for both a direct negative effect and an indirect non-linear relationship mediated through understory plant cover. Soil organic matter appeared to have a positive influence on understory richness that was independent of soil nitrogen. Richness was lowest where the forest overstory was densest, which can be explained through indirect effects on soil organic matter, soil nitrogen and understory cover. Finally, model results suggest a variety of direct and indirect processes whereby mineral soil properties can influence richness. Conclusions: Understory plant species richness and plant cover in P. ponderosa forests appear to be significantly influenced by soil organic matter and nitrogen, which are, in turn, related to overstory density and composition and mineral soil properties. Thus, soil properties can impose direct and indirect constraints on local species diversity in ponderosa pine forests. ?? IAVS; Opulus Press.

Investigation of the single Particle Structure of the neutron-rich Sodium Isotopes $^{27-31}\\!$Na

CERN Document Server

2002-01-01

We propose to study the single particle structure of the neutron-rich isotopes $^{27-31}\\!$Na. These isotopes will be investigated via neutron pickup reactions in inverse kinematics on a deuterium and a beryllium target. Scattered beam particles and transfer products are detected in a position sensitive detector located around 0$^\\circ$. De-excitation $\\gamma$-rays emitted after an excited state has been populated will be registered by the MINIBALL Germanium array. The results will shed new light on the structure of the neutron-rich sodium isotopes and especially on the region of strong deformation around the N=20 nucleus $^{31}\\!$Na.

Li-rich layer-structured cathode materials for high energy Li-ion batteries

Science.gov (United States)

Li, Liu; Lee, Kim Seng; Lu, Li

2014-08-01

Li-rich layer-structured xLi2MnO3 ṡ (1 - x)LiMO2 (M = Mn, Ni, Co, etc.) materials have attracted much attention due to their extraordinarily high reversible capacity as the cathode material in Li-ion batteries. To better understand the nature of this type of materials, this paper reviews history of development of the Li-rich cathode materials, and provides in-depth study on complicated crystal structures and reaction mechanisms during electrochemical charge/discharge cycling. Despite the fabulous capability at low rate, several drawbacks still gap this type of high-capacity cathode materials from practical applications, for instance the large irreversible capacity loss at first cycle, poor rate capability, severe voltage decay and capacity fade during electrochemical charge/discharge cycling. This review will also address mechanisms for these inferior properties and propose various possible solutions to solve above issues for future utilization of these cathode materials in commercial Li-ion batteries.

Context-dependent interactions and the regulation of species richness in freshwater fish

Science.gov (United States)

MacDougall, Andrew S.; Harvey, Eric; McCune, Jenny L.; Nilsson, Karin A.; Bennett, Joseph; Firn, Jennifer; Bartley, Timothy; Grace, James B.; Kelly, Jocelyn; Tunney, Tyler D.; McMeans, Bailey; Matsuzaki, Shin-Ichiro S.; Kadoya, Taku; Esch, Ellen; Cazelles, Kevin; Lester, Nigel; McCann, Kevin S.

2018-01-01

Species richness is regulated by a complex network of scale-dependent processes. This complexity can obscure the influence of limiting species interactions, making it difficult to determine if abiotic or biotic drivers are more predominant regulators of richness. Using integrative modeling of freshwater fish richness from 721 lakes along an 11olatitudinal gradient, we find negative interactions to be a relatively minor independent predictor of species richness in lakes despite the widespread presence of predators. Instead, interaction effects, when detectable among major functional groups and 231 species pairs, were strong, often positive, but contextually dependent on environment. These results are consistent with the idea that negative interactions internally structure lake communities but do not consistently ‘scale-up’ to regulate richness independently of the environment. The importance of environment for interaction outcomes and its role in the regulation of species richness highlights the potential sensitivity of fish communities to the environmental changes affecting lakes globally.

Managed forest landscape structure and avian species richness in the southeastern US

Science.gov (United States)

Craig Loehle; T. Bently Wigley; Scott Rutzmoser; John A. Gerwin; Patrick D. Keyser; Richard A. Lancia; Christopher J. Reynolds; Ronald E. Thill; Robert Weih; Don White; Petra Bohall Wood

2005-01-01

Forest structural features at the stand scale (e.g., snags, stem density, species composition) and habitat attributes at larger spatial scales (e.g., landscape pattern, road density) can influence biological diversity and have been proposed as indicators in sustainable forestry programs. This study investigated relationships between such factors and total richness of...

Structure of Ni-rich Ni--Cr--B--Si coating alloys

International Nuclear Information System (INIS)

Knotek, O.; Lugscheider, E.; Reimann, H.

1975-01-01

The structures of quaternary, nickel-rich Ni--Cr--B--Si alloys were analyzed at a constant boron content of 10 at. percent and a temperature of 850 0 C. The composition range for silicide formation was determined. In these quaternary alloys, known binary nickel silicides, nickel and chromium borides, and the ternary silico-boride Ni 6 Si 2 B were confirmed. A new composition for the W 5 Si 3 -type phase in the Ni--B--Si system was proposed. (U.S.)

Relative importance of current and past landscape structure and local habitat conditions for plant species richness in dry grassland-like forest openings.

Science.gov (United States)

Husáková, Iveta; Münzbergová, Zuzana

2014-01-01

In fragmented landscapes, plant species richness may depend not only on local habitat conditions but also on landscape structure. In addition, both present and past landscape structure may be important for species richness. There are, however, only a few studies that have investigated the relative importance of all of these factors. The aim of this study was to examine the effect of current and past landscape structures and habitat conditions on species richness at dry grassland-like forest openings in a forested landscape and to assess their relative importance for species richness. We analyzed information on past and present landscape structures using aerial photographs from 1938, 1973, 1988, 2000 and 2007. We calculated the area of each locality and its isolation in the present and in the past and the continuity of localities in GIS. At each locality, we recorded all vascular plant species (296 species in 110 forest openings) and information on abiotic conditions of the localities. We found that the current species richness of the forest openings was significantly determined by local habitat conditions as well as by landscape structure in the present and in the past. The highest species richness was observed on larger and more heterogeneous localities with rocks and shallow soils, which were already large and well connected to other localities in 1938. The changes in the landscape structure in the past can thus have strong effects on current species richness. Future studies attempting to understand determinants of species diversity in fragmented landscapes should also include data on past landscape structure, as it may in fact be more important than the present structure.

Weakly bound structures in neutron rich Si isotopes

International Nuclear Information System (INIS)

Singh, D.; Saxena, G.; Yadav, H.L.

2009-01-01

Production of radioactive beams have facilitated the nuclear structure studies away from the line of β-stability, especially for the neutron rich drip line nuclei. Theoretical investigations of these nuclei have been carried out by using various approaches viz. few body model or clusters, shell model and mean field theories, both nonrelativistic as well as relativistic mean field (RMF). The advantage of the RMF approach, however, is that in this treatment the spin-orbit interaction is included in a natural way. This is especially advantageous for the description of drip-line nuclei for which the spin-orbit interaction plays an important role. In this communication we report briefly the results of our calculations for the Si isotopes carried out within the framework of RMF + BCS approach

Ice crystallization in ultrafine water-salt aerosols: nucleation, ice-solution equilibrium, and internal structure.

Science.gov (United States)

Hudait, Arpa; Molinero, Valeria

2014-06-04

Atmospheric aerosols have a strong influence on Earth's climate. Elucidating the physical state and internal structure of atmospheric aqueous aerosols is essential to predict their gas and water uptake, and the locus and rate of atmospherically important heterogeneous reactions. Ultrafine aerosols with sizes between 3 and 15 nm have been detected in large numbers in the troposphere and tropopause. Nanoscopic aerosols arising from bubble bursting of natural and artificial seawater have been identified in laboratory and field experiments. The internal structure and phase state of these aerosols, however, cannot yet be determined in experiments. Here we use molecular simulations to investigate the phase behavior and internal structure of liquid, vitrified, and crystallized water-salt ultrafine aerosols with radii from 2.5 to 9.5 nm and with up to 10% moles of ions. We find that both ice crystallization and vitrification of the nanodroplets lead to demixing of pure water from the solutions. Vitrification of aqueous nanodroplets yields nanodomains of pure low-density amorphous ice in coexistence with vitrified solute rich aqueous glass. The melting temperature of ice in the aerosols decreases monotonically with an increase of solute fraction and decrease of radius. The simulations reveal that nucleation of ice occurs homogeneously at the subsurface of the water-salt nanoparticles. Subsequent ice growth yields phase-segregated, internally mixed, aerosols with two phases in equilibrium: a concentrated water-salt amorphous mixture and a spherical cap-like ice nanophase. The surface of the crystallized aerosols is heterogeneous, with ice and solution exposed to the vapor. Free energy calculations indicate that as the concentration of salt in the particles, the advance of the crystallization, or the size of the particles increase, the stability of the spherical cap structure increases with respect to the alternative structure in which a core of ice is fully surrounded by

Re-Structuring of Marine Communities Exposed to Environmental Change: A Global Study on the Interactive Effects of Species and Functional Richness

Science.gov (United States)

Wahl, Martin; Link, Heike; Alexandridis, Nicolaos; Thomason, Jeremy C.; Cifuentes, Mauricio; Costello, Mark J.; da Gama, Bernardo A. P.; Hillock, Kristina; Hobday, Alistair J.; Kaufmann, Manfred J.; Keller, Stefanie; Kraufvelin, Patrik; Krüger, Ina; Lauterbach, Lars; Antunes, Bruno L.; Molis, Markus; Nakaoka, Masahiro; Nyström, Julia; bin Radzi, Zulkamal; Stockhausen, Björn; Thiel, Martin; Vance, Thomas; Weseloh, Annika; Whittle, Mark; Wiesmann, Lisa; Wunderer, Laura; Yamakita, Takehisa; Lenz, Mark

2011-01-01

Species richness is the most commonly used but controversial biodiversity metric in studies on aspects of community stability such as structural composition or productivity. The apparent ambiguity of theoretical and experimental findings may in part be due to experimental shortcomings and/or heterogeneity of scales and methods in earlier studies. This has led to an urgent call for improved and more realistic experiments. In a series of experiments replicated at a global scale we translocated several hundred marine hard bottom communities to new environments simulating a rapid but moderate environmental change. Subsequently, we measured their rate of compositional change (re-structuring) which in the great majority of cases represented a compositional convergence towards local communities. Re-structuring is driven by mortality of community components (original species) and establishment of new species in the changed environmental context. The rate of this re-structuring was then related to various system properties. We show that availability of free substratum relates negatively while taxon richness relates positively to structural persistence (i.e., no or slow re-structuring). Thus, when faced with environmental change, taxon-rich communities retain their original composition longer than taxon-poor communities. The effect of taxon richness, however, interacts with another aspect of diversity, functional richness. Indeed, taxon richness relates positively to persistence in functionally depauperate communities, but not in functionally diverse communities. The interaction between taxonomic and functional diversity with regard to the behaviour of communities exposed to environmental stress may help understand some of the seemingly contrasting findings of past research. PMID:21611170

International symposium on exotic nuclear structures. Book of abstracst

International Nuclear Information System (INIS)

2000-01-01

The following topics were discussed at the meeting: Physics of weakly bound nuclei, neutron skin and halo; Evolution of shell structures for neutron-rich nuclei; Collective excitations in nuclei with exotic nuclear shapes; Cluster structures; Super- and hyperdeformed nuclei, exotic structures in the actinides; Superheavy elements; Towards understanding the structure of nucleons; New experimental techniques, facilities for radioactive beams. All abstracts (75 items) were submitted as full text to the INIS database. (R.P.)

Internal deformation in layered Zechstein-III K-Mg salts. Structures formed by complex deformation and high contrasts in viscosity observed in drill cores.

Science.gov (United States)

Raith, Alexander; Urai, Janos L.

2016-04-01

During the evaporation of a massive salt body, alternations of interrupted and full evaporation sequences can form a complex layering of different lithologies. Viscosity contrasts of up to five orders of magnitude between these different lithologies are possible in this environment. During the late stage of an evaporation cycle potassium and magnesium (K-Mg) salts are precipitated. These K-Mg salts are of economic interest but also a known drilling hazard due to their very low viscosity. How up to 200m thick layers of these evaporites affect salt deformation at different scales is not well known. A better understanding of salt tectonics with extreme mechanical stratification is needed for better exploration and production of potassium-magnesium salts and to predict the internal structure of potential nuclear waste repositories in salt. To gain a better understanding of the internal deformation of these layers we analyzed K-Mg salt rich drill cores out of the Zechstein III-1b subunit from the Veendam Pillow 10 km southeast of Groningen, near the city Veendam in the NE Netherlands. The study area has a complex geological history with multiple tectonic phases of extension and compression forming internal deformation in the pillow but also conserving most of the original layering. Beside halite the most common minerals in the ZIII-1b are carnallite, kieserite, anhydrite and bischofite alternating in thin layers of simple composition. Seismic interpretation revealed that the internal structure of the Veendam Pillow shows areas, in which the K-Mg salt rich ZIII 1b layer is much thicker than elsewhere, as a result of salt deformation. The internal structure of the ZIII-1b on the other hand, remains unknown. The core analysis shows a strong strain concentration in the weaker Bischofite (MgCl2*6H20) and Carnallite (KMgCl3*6H20) rich layers producing tectonic breccias and highly strained layers completely overprinting the original layering. Layers formed by alternating beds

A reexamination and extension of international strategy-structure theory

OpenAIRE

Wolf, Joachim; Egelhoff, William G.

2001-01-01

Using a sample of 95 German firms, the study finds general support for the traditional fits of international strategy-structure theory. Employing an information-processing perspective, the study conceptually and empirically extends existing theory (1) to address strategy-structure fit for various types of matrix structure, and (2) by adding two new elements of international strategy to the existing international strategy-structure model: the level of international transfers and level of forei...

Effects of habitat structure on the epifaunal community in Mussismilia corals: does coral morphology influence the richness and abundance of associated crustacean fauna?

Science.gov (United States)

Nogueira, Marcos M.; Neves, Elizabeth; Johnsson, Rodrigo

2015-06-01

Coral habitat structures increase abundance and richness of organisms by providing niches, easy access to resources and refuge from predators. Corals harbor a great variety of animals; the variation in coral species morphology contributes to the heterogeneity and complexity of habitat types. In this report, we studied the richness and abundance of crustaceans (Decapoda, Copepoda, Peracarida and Ostracoda) associated with three species of Mussismilia exhibiting different growth morphologies, in two different coral reefs of the Bahia state (Caramuanas and Boipeba-Moreré, Brazil). Mussismilia hispida is a massive coral; M. braziliensis also has a massive growth pattern, but forms a crevice in the basal area of the corallum; M. harttii has a meandroid pattern. PERMANOVA analysis suggests significant differences in associated fauna richness among Mussismilia species, with higher values for M. harttii, followed by M. braziliensis and later by M. hispida. The same trend was observed for density, except that the comparison of M. braziliensis and M. hispida did not show differences. Redundancy and canonical correspondence analysis indicated that almost all of the crustacean species were more associated with the M. harttii colonies that formed a group clearly separated from colonies of M. braziliensis and M. hispida. We also found that the internal volume of interpolyp space, only present in M. harttii, was the most important factor influencing richness and abundance of all analyzed orders of crustaceans.

Tetrahelical structural family adopted by AGCGA-rich regulatory DNA regions

Science.gov (United States)

Kocman, Vojč; Plavec, Janez

2017-05-01

Here we describe AGCGA-quadruplexes, an unexpected addition to the well-known tetrahelical families, G-quadruplexes and i-motifs, that have been a focus of intense research due to their potential biological impact in G- and C-rich DNA regions, respectively. High-resolution structures determined by solution-state nuclear magnetic resonance (NMR) spectroscopy demonstrate that AGCGA-quadruplexes comprise four 5'-AGCGA-3' tracts and are stabilized by G-A and G-C base pairs forming GAGA- and GCGC-quartets, respectively. Residues in the core of the structure are connected with edge-type loops. Sequences of alternating 5'-AGCGA-3' and 5'-GGG-3' repeats could be expected to form G-quadruplexes, but are shown herein to form AGCGA-quadruplexes instead. Unique structural features of AGCGA-quadruplexes together with lower sensitivity to cation and pH variation imply their potential biological relevance in regulatory regions of genes responsible for basic cellular processes that are related to neurological disorders, cancer and abnormalities in bone and cartilage development.

Heavy metals pollution influence the community structure of Cyanobacteria in nutrient rich tropical estuary

Digital Repository Service at National Institute of Oceanography (India)

Anas, A.; Jasmin, C.; Sheeba V.A.; Gireeshkumar, T.R; Nair, S.

, Mn, Fe, Ni, Cu and Zn) on community structure of cyanobacteria in a nutrient rich tropical estuary, Cochin Estuary (CE), across the southwest coast of India. Dissolved heavy metals were higher in CE during dry season, with Zn as major pollutant...

Internal friction behavior of liquid Bi-Sn alloys

International Nuclear Information System (INIS)

Wu Aiqing; Guo Lijun; Liu Changsong; Jia Erguang; Zhu Zhengang

2005-01-01

Pure Bi and Sn and four Bi-Sn alloys distributed on the entire concentration range were selected for internal-friction investigation over a wide temperature range. There exist two peaks in the plots of internal friction versus temperature for liquid Sn, Bi-Sn60 and Bi-Sn90 alloys, one peak being located at about 480 - bar Cand another at about 830 - bar C. Only a single internal-friction peak at about 830 - bar C occurs in liquid Bi-Sn43 (eutectic composition). No internal-friction peak appears in liquid Bi-Sn20 alloy and pure Bi. The height of the internal-friction peaks depends on the content of Sn. The present finding suggests that Sn-rich Bi-Sn alloys may inherit the internal-friction behaviors of pure Sn, whereas Bi-rich Bi-Sn alloy seems to be like pure Bi. The position of the internal-friction peaks is frequency dependent, which resembles the internal-friction feature in structure transition in solids

Internal friction behavior of liquid Bi-Sn alloys

Energy Technology Data Exchange (ETDEWEB)

Wu Aiqing [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P.O. Box 1129, Hefei 230031 (China); Guo Lijun [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P.O. Box 1129, Hefei 230031 (China); Liu Changsong [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P.O. Box 1129, Hefei 230031 (China); Jia Erguang [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P.O. Box 1129, Hefei 230031 (China); Zhu Zhengang [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P.O. Box 1129, Hefei 230031 (China)]. E-mail: zgzhu@issp.ac.cn

2005-12-01

Pure Bi and Sn and four Bi-Sn alloys distributed on the entire concentration range were selected for internal-friction investigation over a wide temperature range. There exist two peaks in the plots of internal friction versus temperature for liquid Sn, Bi-Sn60 and Bi-Sn90 alloys, one peak being located at about 480{sup -}bar Cand another at about 830{sup -}bar C. Only a single internal-friction peak at about 830{sup -}bar C occurs in liquid Bi-Sn43 (eutectic composition). No internal-friction peak appears in liquid Bi-Sn20 alloy and pure Bi. The height of the internal-friction peaks depends on the content of Sn. The present finding suggests that Sn-rich Bi-Sn alloys may inherit the internal-friction behaviors of pure Sn, whereas Bi-rich Bi-Sn alloy seems to be like pure Bi. The position of the internal-friction peaks is frequency dependent, which resembles the internal-friction feature in structure transition in solids.

Organizational Structures that Support Internal Program Evaluation

Science.gov (United States)

Lambur, Michael T.

2008-01-01

This chapter explores how the structure of large complex organizations such as Cooperative Extension affects their ability to support internal evaluation of their programs and activities. Following a literature review of organizational structure and its relation to internal evaluation capacity, the chapter presents the results of interviews with…

Structure of neutron-rich nuclei around the N = 50 shell-gap closure

Science.gov (United States)

Faul, T.; Duchêne, G.; Thomas, J.-C.; Nowacki, F.; Huyse, M.; Van Duppen, P.

2010-04-01

The structure of neutron-rich nuclei in the vicinity of 78Ni have been investigated via the β-decay of 71,73,75Cu isotopes (ISOLDE, CERN). Experimental results have been compared with shell-model calculations performed with the ANTOINE code using a large (2p3/21f5/22p1/21g9/2) valence space and a 56/28Ni28 core.

Rich club analysis in the Alzheimer's disease connectome reveals a relatively undisturbed structural core network.

Science.gov (United States)

Daianu, Madelaine; Jahanshad, Neda; Nir, Talia M; Jack, Clifford R; Weiner, Michael W; Bernstein, Matt A; Thompson, Paul M

2015-08-01

Diffusion imaging can assess the white matter connections within the brain, revealing how neural pathways break down in Alzheimer's disease (AD). We analyzed 3-Tesla whole-brain diffusion-weighted images from 202 participants scanned by the Alzheimer's Disease Neuroimaging Initiative-50 healthy controls, 110 with mild cognitive impairment (MCI) and 42 AD patients. From whole-brain tractography, we reconstructed structural brain connectivity networks to map connections between cortical regions. We tested whether AD disrupts the "rich club" - a network property where high-degree network nodes are more interconnected than expected by chance. We calculated the rich club properties at a range of degree thresholds, as well as other network topology measures including global degree, clustering coefficient, path length, and efficiency. Network disruptions predominated in the low-degree regions of the connectome in patients, relative to controls. The other metrics also showed alterations, suggesting a distinctive pattern of disruption in AD, less pronounced in MCI, targeting global brain connectivity, and focusing on more remotely connected nodes rather than the central core of the network. AD involves severely reduced structural connectivity; our step-wise rich club coefficients analyze points to disruptions predominantly in the peripheral network components; other modalities of data are needed to know if this indicates impaired communication among non rich club regions. The highly connected core was relatively preserved, offering new evidence on the neural basis of progressive risk for cognitive decline. © 2015 Wiley Periodicals, Inc.

Solution structure of the twelfth cysteine-rich ligand-binding repeat in rat megalin

International Nuclear Information System (INIS)

Wolf, Christian A.; Dancea, Felician; Shi Meichen; Bade-Noskova, Veronika; Rueterjans, Heinz; Kerjaschki, Dontscho; Luecke, Christian

2007-01-01

Megalin, an approx. 600 kDa transmembrane glycoprotein that acts as multi-ligand transporter, is a member of the low density lipoprotein receptor gene family. Several cysteine-rich repeats, each consisting of about 40 residues, are responsible for the multispecific binding of ligands. The solution structure of the twelfth cysteine-rich ligand-binding repeat with class A motif found in megalin features two short β-strands and two helical turns, yielding the typical fold with a I-III, II-V and IV-VI disulfide bridge connectivity pattern and a calcium coordination site at the C-terminal end. The resulting differences in electrostatic surface potential compared to other ligand-binding modules of this gene family, however, may be responsible for the functional divergence

Fabrication of an Organic Light-Emitting Diode from New Host π Electron Rich Zinc Complex

Science.gov (United States)

Jafari, Mohammad Reza; Janghouri, Mohammad; Shahedi, Zahra

2017-01-01

A new π electron rich zinc complex was used as a fluorescent material in organic light-emitting diodes (OLEDs). Devices with a structure of indium tin oxide/poly (3,4-ethylenedi-oxythiophene):poly(styrenesulfonate) (PEDOT: PSS) (50 nm)/polyvinylcarbazole (60 nm)/Zn: %2 porphyrin derivatives (45 nm)/Al (150 nm) were fabricated. Porphyrin derivatives accounting for 2 wt.% in the π electron rich zinc complex were used as a host. The electroluminescence (EL) spectra of porphyrin derivatives indicated a red shift, as π electron rich zinc complex EL spectra. The device (4) has also a luminance of 3420 cd/m2 and maximum efficiency of 1.58 cd/A at 15 V, which are the highest values among four devices. The result of Commission International del'Eclairage (CIE) (X, Y) coordinate and EL spectrum of device (3) indicated that it is more red shifted compared to other devices. Results of this work indicate that π electron rich zinc complex is a promising host material for high efficiency red OLEDs and has a simple structure compared to Alq3-based devices.

Structure of molecules and internal rotation

CERN Document Server

Mizushima, San-Ichiro

1954-01-01

Structure of Molecules and Internal Rotation reviews early studies on dihalogenoethanes. This book is organized into two parts encompassing 8 chapters that evaluate the Raman effect in ethane derivatives, the energy difference between rotational isomers, and the infrared absorption of ethane derivatives. Some of the topics covered in the book are the potential barrier to internal rotation; nature of the hindering potential; entropy difference between the rotational isomers; internal rotation in butane, pentane, and hexane; and internal rotation in long chain n-paraffins. Other chapters deal wi

Three-dimensional structure and cytokine distribution of platelet-rich fibrin.

Science.gov (United States)

Bai, Meng-Yi; Wang, Ching-Wei; Wang, Jyun-Yi; Lin, Ming-Fang; Chan, Wing P

2017-02-01

Previous reports have revealed that several cytokines (including platelet-derived growth factor-BB, transforming growth factors-β1 and insulin-like growth factor-1) can enhance the rate of bone formation and synthesis of extracellular matrix in orthopaedics or periodontology. This study aimed to determine the concentration of cytokines within platelet-rich fibrin microstructures and investigate whether there are differences in the different portions of platelet-rich fibrin, which has implications for proper clinical use of platelet-rich fibrin gel. Whole blood was obtained from six New Zealand rabbits (male, 7 to 39 weeks old, weight 2.7-4 kg); it was then centrifuged for preparation of platelet-rich fibrin gels and harvest of plasma. The resultant platelet-rich fibrin gels were used for cytokine determination, histological analyses and scanning electron microscopy. All plasmas obtained were subject to the same cytokine determination assays for the purpose of comparison. Cytokines platelet-derived growth factor-BB and transforming growth factor-β1 formed concentration gradients from high at the red blood cell end of the platelet-rich fibrin gel (p=1.88×10-5) to low at the plasma end (p=0.19). Insulin-like growth factor-1 concentrations were similar at the red blood cell and plasma ends. The porosities of the platelet-rich fibrin samples taken in sequence from the red blood cell end to the plasma end were 6.5% ± 4.9%, 24.8% ± 7.5%, 30.3% ± 8.5%, 41.4% ± 12.3%, and 40.3% ± 11.7%, respectively, showing a gradual decrease in the compactness of the platelet-rich fibrin network. Cytokine concentrations are positively associated with platelet-rich fibrin microstructure and portion in a rabbit model. As platelet-rich fibrin is the main entity currently used in regenerative medicine, assessing cytokine concentration and the most valuable portion of PRF gels is essential and recommended to all physicians.

Three-dimensional structure and cytokine distribution of platelet-rich fibrin

Directory of Open Access Journals (Sweden)

Meng-Yi Bai

Full Text Available OBJECTIVES: Previous reports have revealed that several cytokines (including platelet-derived growth factor-BB, transforming growth factors-β1 and insulin-like growth factor-1 can enhance the rate of bone formation and synthesis of extracellular matrix in orthopaedics or periodontology. This study aimed to determine the concentration of cytokines within platelet-rich fibrin microstructures and investigate whether there are differences in the different portions of platelet-rich fibrin, which has implications for proper clinical use of platelet-rich fibrin gel. METHODS: Whole blood was obtained from six New Zealand rabbits (male, 7 to 39 weeks old, weight 2.7-4 kg; it was then centrifuged for preparation of platelet-rich fibrin gels and harvest of plasma. The resultant platelet-rich fibrin gels were used for cytokine determination, histological analyses and scanning electron microscopy. All plasmas obtained were subject to the same cytokine determination assays for the purpose of comparison. RESULTS: Cytokines platelet-derived growth factor-BB and transforming growth factor-β1 formed concentration gradients from high at the red blood cell end of the platelet-rich fibrin gel (p=1.88×10-5 to low at the plasma end (p=0.19. Insulin-like growth factor-1 concentrations were similar at the red blood cell and plasma ends. The porosities of the platelet-rich fibrin samples taken in sequence from the red blood cell end to the plasma end were 6.5% ± 4.9%, 24.8% ± 7.5%, 30.3% ± 8.5%, 41.4% ± 12.3%, and 40.3% ± 11.7%, respectively, showing a gradual decrease in the compactness of the platelet-rich fibrin network. CONCLUSION: Cytokine concentrations are positively associated with platelet-rich fibrin microstructure and portion in a rabbit model. As platelet-rich fibrin is the main entity currently used in regenerative medicine, assessing cytokine concentration and the most valuable portion of PRF gels is essential and recommended to all physicians.

Magnetosheath jets: MMS observations of internal structures and jet interactions with ambient plasma

Science.gov (United States)

Plaschke, F.; Karlsson, T.; Hietala, H.; Archer, M. O.; Voros, Z.; Nakamura, R.; Magnes, W.; Baumjohann, W.; Torbert, R. B.; Russell, C. T.; Giles, B. L.

2017-12-01

The dayside magnetosheath downstream of the quasi-parallel bow shock is commonly permeated by high-speed jets. Under low IMF cone angle conditions, large scale jets alone (with cross-sectional diameters of over 2 Earth radii) have been found to impact the subsolar magnetopause once every 6 minutes - smaller scale jets occurring much more frequently. The consequences of jet impacts on the magnetopause can be significant: they may trigger local reconnection and waves, alter radiation belt electron drift paths, disturb the geomagnetic field, and potentially generate diffuse throat aurora at the dayside ionosphere. Although some basic statistical properties of jets are well-established, their internal structure and interactions with the surrounding magnetosheath plasma are rather unknown. We present Magnetospheric Multiscale (MMS) observations which reveal a rich jet-internal structure of high-amplitude plasma moment and magnetic field variations and associated currents. These variations/structures are generally found to be in thermal and magnetic pressure balance; they mostly (but not always) convect with the plasma flow. Small velocity differences between plasma and structures are revealed via four-spacecraft timing analysis. Inside a jet core region, where the plasma velocity maximizes, structures are found to propagate forward (i.e., with the jet), whereas backward propagation is found outside that core region. Although super-magnetosonic flows are detected by MMS in the spacecraft frame of reference, no fast shock is seen as the jet plasma is sub-magnetosonic with respect to the ambient magnetosheath plasma. Instead, the fast jet plasma pushes ambient magnetosheath plasma ahead of the jet out of the way, possibly generating anomalous sunward flows in the vicinity, and modifies the magnetic field aligning it with the direction of jet propagation.

Nuclear structure far from stability: the neutron-rich 69-79Cu isotopes

International Nuclear Information System (INIS)

Franchoo, Serge

2015-01-01

Far from stability, the nuclear structure that is predicted by the shell model is evolving. Old magic numbers disappear, while new ones appear. Our understanding of the underlying nuclear force that drives these changes is still incomplete. After a short overview across the nuclear chart, we discuss the strength functions of the shell-model orbitals in the neutron-rich copper isotopes towards the 78 Ni doubly-magic nucleus. These were measured in a 72 Zn(d, 3 He) 71 Cu proton pick-up reaction in inverse kinematics with a radioactive beam at the Ganil laboratory in France. We also present the latest results from a 80 Zn(p,2p) 79 Cu knockout experiment at Riken in Japan, leading to selective population of hole states in 79 Cu. Our findings show that the Z=28 shell gap in the neutron-rich copper isotopes is surprisingly steady against the addition of neutrons beyond N=40. (author)

Crystal structure and dimerization equilibria of PcoC, a methionine-rich copper resistance protein from Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Wernimont, A.K.; Huffman, D.L.; Finney, L.A.; Demeler, B.; O' Halloran, T.V.; Rosenzweig, A.C.

2010-03-08

PcoC is a soluble periplasmic protein encoded by the plasmid-born pco copper resistance operon of Escherichia coli. Like PcoA, a multicopper oxidase encoded in the same locus and its chromosomal homolog CueO, PcoC contains unusual methionine rich sequences. Although essential for copper resistance, the functions of PcoC, PcoA, and their conserved methionine-rich sequences are not known. Similar methionine motifs observed in eukaryotic copper transporters have been proposed to bind copper, but there are no precedents for such metal binding sites in structurally characterized proteins. The high-resolution structures of apo PcoC, determined for both the native and selenomethionine-containing proteins, reveal a seven-stranded barrel with the methionines unexpectedly housed on a solvent-exposed loop. Several potential metal-binding sites can be discerned by comparing the structures to spectroscopic data reported for copper-loaded PcoC. In the native structure, the methionine loop interacts with the same loop on a second molecule in the asymmetric unit. In the selenomethionine structure, the methionine loops are more exposed, forming hydrophobic patches on the protein surface. These two arrangements suggest that the methionine motifs might function in protein-protein interactions between PcoC molecules or with other methionine-rich proteins such as PcoA. Analytical ultracentrifugation data indicate that a weak monomer-dimer equilibrium exists in solution for the apo protein. Dimerization is significantly enhanced upon binding Cu(I) with a measured {Delta}({Delta}G{sup o}) {le} -8.0 kJ/mole, suggesting that copper might bind at the dimer interface.

Synthesis and study of neutron-rich nuclides

International Nuclear Information System (INIS)

Luo Yixiao

1995-01-01

During the past few years our understanding of the decay properties and nuclear structure has been extended in a systematic fashion for the neutron-rich nuclei. This review will first sketch the production and identification of the neutron-rich nuclei throughout the whole mass region, and will then discuss the impressive progress in the studies of the exotic decay properties and nuclear structure of neutron-rich nuclei. Their astrophysical implications will also be outlined

Benthic megafaunal community structure of cobalt-rich manganese crusts on Necker Ridge

Science.gov (United States)

Morgan, Nicole B.; Cairns, Stephen; Reiswig, Henry; Baco, Amy R.

2015-10-01

In the North Pacific Ocean, the seamounts of the Hawaiian Archipelago and the Mid-Pacific Mountains are connected by Necker Ridge, a 600 km-long feature spanning a depth range of 1400-4000 m. The Necker Ridge is a part of a large area of the central and western Pacific under consideration for cobalt-rich manganese crust mining. We describe the fauna and community structure of the previously unsampled Necker Ridge based on explorations with the submersible Pisces IV. On five pinnacles and a portion of the Ridge ranging from 1400 to 2000 m deep, 27 transects were recorded using HD video, and voucher specimens were collected to aid in species identification. The video was analyzed to identify and count the megafauna found on each transect and to characterize the substrate. Diversity increased from south to north along the feature. There was a significant difference in community structure between southern and northern pinnacles, with southern pinnacles dominated by crinoids of the Family Charitometridae and northern pinnacles dominated by octocorals, especially the Families Isididae and Chrysogorgiidae. DistLM demonstrated a correlation between community structure on the pinnacles and at least six environmental variables, including latitude, sediment cover, and oxygen concentration, but not including depth. The discontinuous and patchy nature of these distinct megafaunal communities highlights growing evidence that cobalt-rich seamounts are highly heterogeneous habitats, and that managing seamounts may require more complex regulations than treating them as a single ecological unit. These results suggest that extensive community analysis should occur at a given site to determine management priority areas, prior to consideration of that site for exploitation of natural resources.

Rich RNA Structure Landscapes Revealed by Mutate-and-Map Analysis.

Directory of Open Access Journals (Sweden)

Pablo Cordero

2015-11-01

Full Text Available Landscapes exhibiting multiple secondary structures arise in natural RNA molecules that modulate gene expression, protein synthesis, and viral infection [corrected]. We report herein that high-throughput chemical experiments can isolate an RNA's multiple alternative secondary structures as they are stabilized by systematic mutagenesis (mutate-and-map, M2 and that a computational algorithm, REEFFIT, enables unbiased reconstruction of these states' structures and populations. In an in silico benchmark on non-coding RNAs with complex landscapes, M2-REEFFIT recovers 95% of RNA helices present with at least 25% population while maintaining a low false discovery rate (10% and conservative error estimates. In experimental benchmarks, M2-REEFFIT recovers the structure landscapes of a 35-nt MedLoop hairpin, a 110-nt 16S rRNA four-way junction with an excited state, a 25-nt bistable hairpin, and a 112-nt three-state adenine riboswitch with its expression platform, molecules whose characterization previously required expert mutational analysis and specialized NMR or chemical mapping experiments. With this validation, M2-REEFFIT enabled tests of whether artificial RNA sequences might exhibit complex landscapes in the absence of explicit design. An artificial flavin mononucleotide riboswitch and a randomly generated RNA sequence are found to interconvert between three or more states, including structures for which there was no design, but that could be stabilized through mutations. These results highlight the likely pervasiveness of rich landscapes with multiple secondary structures in both natural and artificial RNAs and demonstrate an automated chemical/computational route for their empirical characterization.

The gender wage gap in an international perspective

OpenAIRE

Plasman, Robert; Sissoko Ndeye, Salimata

2005-01-01

Using a rich and comparable matched employer-employee data set, we analyse international differences in gender pay gaps in the private sector for a sample of five European economies: Belgium, Denmark, Ireland, Italy and Spain. Using different methods, we examine how wage structure, differences in the distribution of measured characteristics and occupational segregation contribute to explain the pattern of international differences. Furthermore, we take account of the fact that indirect discri...

The International Standards Organisation offshore structures standard

International Nuclear Information System (INIS)

Snell, R.O.

1994-01-01

The International Standards Organisation has initiated a program to develop a suite of ISO Codes and Standards for the Oil Industry. The Offshore Structures Standard is one of seven topics being addressed. The scope of the standard will encompass fixed steel and concrete structures, floating structures, Arctic structures and the site specific assessment of mobile drilling and accommodation units. The standard will use as base documents the existing recommended practices and standards most frequently used for each type of structure, and will develop them to incorporate best published and recognized practice and knowledge where it provides a significant improvement on the base document. Work on the Code has commenced under the direction of an internationally constituted sub-committee comprising representatives from most of the countries with a substantial offshore oil and gas industry. This paper outlines the background to the code and the format, content and work program

Internal structure of magnetic endosomes

Science.gov (United States)

Rivière, C.; Wilhelm, C.; Cousin, F.; Dupuis, V.; Gazeau, F.; Perzynski, R.

2007-01-01

The internal structure of biological vesicles filled with magnetic nanoparticles is investigated using the following complementary analyses: electronic transmission microscopy, dynamic probing by magneto-optical birefringence and structural probing by Small Angle Neutron Scattering (SANS). These magnetic vesicles are magnetic endosomes obtained via a non-specific interaction between cells and anionic magnetic iron oxide nanoparticles. Thanks to a magnetic purification process, they are probed at two different stages of their formation within HeLa cells: (i) adsorption of nanoparticles onto the cellular membrane and (ii) their subsequent internalisation within endosomes. Differences in the microenvironment of the magnetic nanoparticles at those two different stages are highlighted here. The dynamics of magnetic nanoparticles adsorbed onto cellular membranes and confined within endosomes is respectively 3 and 5 orders of magnitude slower than for isolated magnetic nanoparticles in aqueous media. Interestingly, SANS experiments show that magnetic endosomes have an internal structure close to decorated vesicles, with magnetic nanoparticles locally decorating the endosome membrane, inside their inner-sphere. These results, important for future biomedical applications, suggest that multiple fusions of decorated vesicles are the biological processes underlying the endocytosis of that kind of nanometric materials.

Internal structure of reactor building for Madras Atomic Power Project

International Nuclear Information System (INIS)

Pandit, D.P.

1975-01-01

The structural configuration and analysis of structural elements of the internal structure of reactor building for the Madras Atomic Power Project has been presented. Two methods of analysis of the internal structure, viz. Equivalent Plane Frame and Finite Element Method, are explained and compared with the use of bending moments obtained. (author)

Molecular cloning and construction of the coding region for human acetylcholinesterase reveals a G + C-rich attenuating structure

International Nuclear Information System (INIS)

Soreq, H.; Ben-Aziz, R.; Prody, C.A.; Seidman, S.; Gnatt, A.; Neville, L.; Lieman-Hurwitz, J.; Lev-Lehman, E.; Ginzberg, D.; Lapidot-Lifson, Y.; Zakut, H.

1990-01-01

To study the primary structure of human acetylcholinesterase and its gene expression and amplification, cDNA libraries from human tissues expressing oocyte-translatable AcChoEase mRNA were constructed and screened with labeled oligodeoxynucleotide probes. Several cDNA clones were isolated that encoded a polypeptide with ≥50% identically aligned amino acids to Torpedo AcChoEase and human butyrylcholinesterase. However, these cDNA clones were all truncated within a 300-nucleotide-long G + C-rich region with a predicted pattern of secondary structure having a high Gibbs free energy downstream from the expected 5' end of the coding region. Screening of a genomic DNA library revealed the missing 5' domain. When ligated to the cDNA and constructed into a transcription vector, this sequence encoded a synthetic mRNA translated in microinjected oocytes into catalytically active AcChoEase with marked preference for acetylthiocholine over butyrylthiocholine as a substrate, susceptibility to inhibition by the AcChoEase inhibitor BW284C51, and resistance to the AcChoEase inhibitor tetraisopropylpyrophosphoramide. Blot hybridization of genomic DNA from different individuals carrying amplified AcChoEase genes revealed variable intensities and restriction patterns with probes from the regions upstream and downstream from the predicted G + C-rich structure. Thus, the human AcChoEase gene includes a putative G + C-rich attenuator domain and is subject to structural alterations in cases of AcChoEase gene amplification

Structure of light proton-rich nuclei on the drip-line

International Nuclear Information System (INIS)

Guimaraes, V.; Toyokawa, H.; Yun, C.C.; Niizeki, T.; Ito, K.; Kishida, T.; Kubo, T.; Pu, Y.; Ohura, M.; Orihara, H.; Terakawa, T.; Hamada, S.; Hirai, M.; Miyatake, H.

1995-01-01

Among proton-rich unstable nuclei on the light proton drip-line, nuclear structure of 21 Mg, 17 Ne, 13 O, 11 N and 9 C have been investigated by the three-neutron pick-up reaction ( 3 He, 6 He). The angular distributions measured for this reaction have shown a characteristic feature of a transferred angular-momentum (L) dependence, which provides spin-parity assignments for the new levels in these nuclei. Here, the results on the nuclear structure of 17 Ne and 11 N are reported. The nucleus 17 Ne we almost unknown before, except that the mass excess had been determined and a few states had been suggested. Many T = 3/2 states were known in the other three members ( 17 N, 17 O and 17 F). Thus, the inclusion of the data on 17 Ne levels has enabled an extensive analysis in terms of the Isobaric Multiplet Mass Equation (IMME) for several excited state quartets. This is the first report on such an extensive analysis in the same mass ststem for a wide range in excitation energy. The 11 N nucleus was investigated to learn about the structure of A 11 system. This mass has been intensively studied, specially because of the halo structure observed in 11 Li and the spin parity-inversion of the 11 Be ground-state. The 11 N nucleus was totally unknown before except for the possible ground state

Synthesis and study of neutron-rich nuclides

International Nuclear Information System (INIS)

Luo, Y.X.

1995-01-01

During the past few years our understanding of the decay properties and nuclear structure has been extended in a systematic fashion for the neutron-rich nuclei. This review will discuss the impressive progress in the studies of the exotic decay properties and nuclear structure of n-rich nuclei. Their astrophysical implications will also be outlined. ((orig.))

Structure dependent electrochemical performance of Li-rich layered oxides in lithium-ion batteries

Energy Technology Data Exchange (ETDEWEB)

Fu, Fang; Yao, Yuze; Wang, Haiyan; Xu, Gui-Liang; Amine, Khalil; Sun, Shi-Gang; Shao, Minhua

2017-04-08

Rational and precise control of the structure and dimension of electrode materials is an efficient way to improve their electrochemical performance. In this work, solvothermal or co-precipitation method is used to synthesize lithium-rich layered oxide materials of Li1.2Mn0.56Co0.12Ni0.12O2 (LLO) with various morphologies and structures, including microspheres, microrods, nanoplates, and irregular nanoparticles. These materials exhibit strong structure- dependent electrochemical properties. The porous hierarchical structured LLO microrods exhibit the best performance, delivering a discharge capacity of 264.6 mAh g(-1) at 0.5 C with over 91% retention after 100 cycles. At a high rate of 5 C, a high discharge capacity of 173.6 mAh g(-1) can be achieved. This work reveals the relationship between the morphologies and electrochemical properties of LLO cathode materials, and provides a feasible approach to fabricating robust and high-performance electrode materials for lithium-ion batteries.

Mirror energy difference and the structure of loosely bound proton-rich nuclei around A =20

Science.gov (United States)

Yuan, Cenxi; Qi, Chong; Xu, Furong; Suzuki, Toshio; Otsuka, Takaharu

2014-04-01

The properties of loosely bound proton-rich nuclei around A =20 are investigated within the framework of the nuclear shell model. In these nuclei, the strength of the effective interactions involving the loosely bound proton s1/2 orbit is significantly reduced in comparison with that of those in their mirror nuclei. We evaluate the reduction of the effective interaction by calculating the monopole-based-universal interaction (VMU) in the Woods-Saxon basis. The shell-model Hamiltonian in the sd shell, such as USD, can thus be modified to reproduce the binding energies and energy levels of the weakly bound proton-rich nuclei around A =20. The effect of the reduction of the effective interaction on the structure and decay properties of these nuclei is also discussed.

Nuclear structure studies of neutron-rich heavy nuclei by mass measurements of francium and radium isotopes

Energy Technology Data Exchange (ETDEWEB)

Rosenbusch, Marco [Ernst-Moritz-Arndt-Universitaet, Institut fuer Physik, 17487 Greifswald (Germany); Collaboration: ISOLTRAP-Collaboration

2013-07-01

The mass is a unique property of an atomic nucleus reflecting its binding energy and thus the sum of all interactions at work. Precise measurements of nuclear masses especially of short-lived exotic nuclides provide important input for nuclear structure, nuclear astrophysics, tests of the Standard Model, and weak interaction studies. The Penning-trap mass spectrometer ISOLTRAP at the on-line isotope separator ISOLDE/CERN has been set up for precision mass measurements and continuously improved for accessing more exotic nuclides. The mass uncertainty is typically δm / m=10{sup -8} and the accessible half-life has been reduced to about 50 ms. In this contribution, the results of a measurement campaign of neutron-rich francium and radium isotopes will be presented, i.e. the masses of the isotopic chain of {sup 224-233}Fr and {sup 233,234}Ra, one of the most neutron-rich ensemble obtainable at ISOL facilities. The mass {sup 234}Ra denotes the heaviest mass ever measured with ISOLTRAP. Experimental data in the neutron-rich, heavy mass region is of great interest for studies of structural evolution far from stability, especially because the knowledge from nuclear mass models is scarce. The impact of the new data on the physics in this mass region as well as recent technical developments of ISOLTRAP are discussed.

Microdiffraction and CBED crystal structure determination of the Si-rich phase in laser-clad Ni alloy FP-5

International Nuclear Information System (INIS)

Liu, Y.; Mazumder, J.

1995-01-01

This paper demonstrates an example of using kinematical microdiffraction to solve an unknown Si-rich phase of micrometer size in a laser-clad Ni alloy FP-5 on Al alloy AA333. The composition of the Si-rich phase obtained by energy-dispersice X-ray spectroscopy (EDX) analysis in a transmission electron microscope is approximately 0.7wt%Al, 71wt%Si, 3.3wt%Cr, 0.8wt%Fe, 21wt%Ni and 2.8wt%Cu. The point group was identified by the standard convergent-beam symmetry analysis to be P6 3 /mmc (No. 194). Structure analysies by microdiffraction (MD) indicates that the Si-rich phase is a close-packed structure.The intensity distribution in the microdiffraction pattern of the [1120] zone axis taken with a very thin area showed a close match with kinematical calculation. A close-packed-structure model specified as ABCACB was deduced from the [1120] zone axis MD pattern. The randomly distributed atoms of all the elements in the unit cell are at 2/3, 1/3-1/12; 1/3, 1/12; 0, 0, 3/12, 1/3, 2/3, 5/12, 2/3, 1/3, 7/12; 0,0, 9/12. The model was checked by comparison with a simulated diffraction pattern map and with a simulated [0001] zone-axis CBED pattern, which showed complete agreement with the proposed model. (orig.)

Enzymatic synthesis of capric acid-rich structured lipids (MUM type) using Candida antarctica lipase.

Science.gov (United States)

SilRoy, Sumita; Ghosh, Mahua

2011-01-01

The objective of the work was to produce capric acid rich structured lipids starting from various Indian indigenous vegetable oils, such as rice bran, ground nut and mustard oils. Acidolysis reaction between individual vegetable oils and capric acid in one is to three molar ratios at 45 degree centigrade temperature was carried out using position specific Candida antarctica lipase so as to protect the Sn-2 position of the oils which are rich in unsaturated fatty acids. The incorporation of capric acid depended on the reaction time showing 6 % within 6 h and 30.8 % in 72 h with rice bran oil. Similarly, in ground nut oil incorporation of capric acid was 34.2 % in 72 h compared to 5.3 % in 6 h. Thus mustard oil showed much lower incorporation than the other two oils, with 3.3 % and 19.5 % in 6 and 72 h respectively. The incorporation of capric acid was influenced by the nature of the fatty acids present in the original oil. The fatty acid composition of Sn-2 position of the structured triacylglycerols of the three oils revealed that capric acid was mainly replacing the fatty acids occupying the Sn-1 and 3 positions of the triglyceride molecule.

Structural manifestations of aging in Se-rich glasses

Science.gov (United States)

Dash, S.; Ravindren, S.; Chen, P.; Boolchand, P.

2015-03-01

We examine weakly cross-linked GexSe100-x (0%modulated DSC and Raman scattering experiments. Homogeneity of melts was carefully verified using FT-Raman line profiling. Upon aging at RT for 4 months, we find the width of the glass transition W(x) steadily decreasing from 10C at 7% Ge to 2C for pure Se. The 5-fold reduction of W(x) with a decrease of Ge content is accompanied by a 2-fold increase in the non-reversing enthalpy. Rejuvenation of the aged glasses changes W(x) from 15C at 7% Ge to 7C for pure Se. Tg is found to decrease upon rejuvenation with the difference (Tg(aged)-Tg(rejuv)) showing a maximum near 3% Ge and vanishing for pure Se and 6% of Ge, which are topological thresholds. These results in Se-rich glasses are consistent with aging induced decoupling of Se8 crowns and growth of extended range structural correlations between polymeric Sen chains due to lone pair interactions. At higher x, near 8-10% of Ge, eutectic effects are manifested. Work supported by NSF Grant DMR 08-53957.

Discrete Optimization of Internal Part Structure via SLM Unit Structure-Performance Database

Directory of Open Access Journals (Sweden)

Li Tang

2018-01-01

Full Text Available The structural optimization of the internal structure of parts based on three-dimensional (3D printing has been recognized as being important in the field of mechanical design. The purpose of this paper is to present a creation of a unit structure-performance database based on the selective laser melting (SLM, which contains various structural units with different functions and records their structure and performance characteristics so that we can optimize the internal structure of parts directly, according to the database. The method of creating the unit structure-performance database was introduced in this paper and several structural units of the unit structure-performance database were introduced. The bow structure unit was used to show how to create the structure-performance database of the unit as an example. Some samples of the bow structure unit were designed and manufactured by SLM. These samples were tested in the WDW-100 compression testing machine to obtain their performance characteristics. After this, the paper collected all data regarding unit structure parameters, weight, performance characteristics, and other data; and, established a complete set of data from the bow structure unit for the unit structure-performance database. Furthermore, an aircraft part was reconstructed conveniently to be more lightweight according to the unit structure-performance database. Its weight was reduced by 36.8% when compared with the original structure, while the strength far exceeded the requirements.

Self-force as probe of internal structure

International Nuclear Information System (INIS)

Isoyama, Soichiro; Poisson, Eric

2012-01-01

The self-force acting on a (scalar or electric) charge held in place outside a massive body contains information about the body's composition, and can therefore be used as a probe of internal structure. We explore this theme by computing the (scalar or electromagnetic) self-force when the body is a spherical ball of perfect fluid in hydrostatic equilibrium, under the assumption that its rest-mass density and pressure are related by a polytropic equation of state. The body is strongly self-gravitating, and all computations are performed in exact general relativity. The dependence on internal structure is best revealed by expanding the self-force in powers of r -1 0 , with r 0 denoting the radial position of the charge outside the body. To the leading order, the self-force scales as r -3 0 and depends only on the square of the charge and the body's mass; the leading self-force is universal. The dependence on internal structure is seen at the next order, r -5 0 , through a structure factor that depends on the equation of state. We compute this structure factor for relativistic polytropes, and show that for a fixed mass, it increases linearly with the body's radius in the case of the scalar self-force, and quadratically with the body's radius in the case of the electromagnetic self-force. In both cases we find that for a fixed mass and radius, the self-force is smaller if the body is more centrally dense, and larger if the mass density is more uniformly distributed. (paper)

Modelling of internal structure in seismic analysis of a PHWR building

International Nuclear Information System (INIS)

Reddy, G.R.; Vaze, K.K.; Kushawaha, H.S.; Ingle, R.K.; Subramanian, K.V.

1991-01-01

Seismic analysis of complex and large structures, consisting of thick shear walls, such as Reactor Building is very involved and time consuming. It is a standard practice to model the structure as a stick model to predict reasonably the dynamic behaviour of the structure. It is required to determine approximate equivalent sectional properties of Internal Structure for representation in the stick model. The restraint to warping can change the stress distribution thus affecting the centre of rigidity and torsional inertia, Hence, standard formulae does not hold good for determination of sectional properties of the Internal Structure. In this case the equivalent sectional properties for the Internal Structure are calculated using a Finite Element Model (FEM) of the Internal Structure and applying unit horizontal forces in each direction. A 3-D stick model is developed using the guidelines. Using the properties calculated by FEM and also by standard formulae, the responses of the 3-D stick model are compared. (J.P.N.)

International Good Market Segmentation and Financial Market Structure

OpenAIRE

Basak, Suleyman; Croitoru, Benjamin

2003-01-01

While financial markets have recently become more complete and international capital flows well liberalized, markets for goods remain segmented. To investigate how more complete security markets may relieve the effects of this segmentation, we examine a series of two-country economies with internationally segmented good markets, distinguished by the available financial securities. We show that, under heterogeneity within countries, the financial structure matters: even with internationally co...

An ezrin-rich, rigid uropod-like structure directs movement of amoeboid blebbing cells.

Science.gov (United States)

Lorentzen, Anna; Bamber, Jeffrey; Sadok, Amine; Elson-Schwab, Ilan; Marshall, Christopher J

2011-04-15

Melanoma cells can switch between an elongated mesenchymal-type and a rounded amoeboid-type migration mode. The rounded 'amoeboid' form of cell movement is driven by actomyosin contractility resulting in membrane blebbing. Unlike elongated A375 melanoma cells, rounded A375 cells do not display any obvious morphological front-back polarisation, although polarisation is thought to be a prerequisite for cell movement. We show that blebbing A375 cells are polarised, with ezrin (a linker between the plasma membrane and actin cytoskeleton), F-actin, myosin light chain, plasma membrane, phosphatidylinositol (4,5)-bisphosphate and β1-integrin accumulating at the cell rear in a uropod-like structure. This structure does not have the typical protruding shape of classical leukocyte uropods, but, as for those structures, it is regulated by protein kinase C. We show that the ezrin-rich uropod-like structure (ERULS) is an inherent feature of polarised A375 cells and not a consequence of cell migration, and is necessary for cell invasion. Furthermore, we demonstrate that membrane blebbing is reduced at this site, leading to a model in which the rigid ezrin-containing structure determines the direction of a moving cell through localised inhibition of membrane blebbing.

Structure of proton-rich nuclei of astrophysical interest

Energy Technology Data Exchange (ETDEWEB)

Roeckl, E [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany)

1998-06-01

Recent experimental data concerning proton-rich nuclei between A=20 and A=100 are presented and discussed with respect to their relevance to the astrophysical rp process and to the calibration of solar neutrino detectors. (orig.)

Structure and stabilization of hydrogen-rich transverse.

Energy Technology Data Exchange (ETDEWEB)

Lyra, Sgouria [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Wilde, B [Georgia Inst. of Technology, Atlanta, GA (United States); Kolla, Hemanth [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Seitzman, J. [Georgia Inst. of Technology, Atlanta, GA (United States); Lieuwen, T. C. [Georgia Inst. of Technology, Atlanta, GA (United States); Chen, Jacqueline H. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

2014-07-01

This paper reports the results of a joint experimental and numerical study of the ow characteristics and flame stabilization of a hydrogen rich jet injected normal to a turbulent, vitiated cross ow of lean methane combustion products. Simultaneous high-speed stereoscopic PIV and OH PLIF measurements were obtained and analyzed alongside three-dimensional direct numerical simulations of inert and reacting JICF with detailed H₂/CO chemistry. Both the experiment and the simulation reveal that, contrary to most previous studies of reacting JICF stabilized in low-to-moderate temperature air cross ow, the present conditions lead to an autoigniting, burner-attached flame that initiates uniformly around the burner edge. Significant asymmetry is observed, however, between the reaction zones located on the windward and leeward sides of the jet, due to the substantially different scalar dissipation rates. The windward reaction zone is much thinner in the near field, while also exhibiting significantly higher local and global heat release than the much broader reaction zone found on the leeward side of the jet. The unsteady dynamics of the windward shear layer, which largely control the important jet/cross flow mixing processes in that region, are explored in order to elucidate the important flow stability implications arising in the reacting JICF. Vorticity spectra extracted from the windward shear layer reveal that the reacting jet is globally unstable and features two high frequency peaks, including a fundamental mode whose Strouhal number of ~0.7 agrees well with previous non-reacting JICF stability studies. The paper concludes with an analysis of the ignition, ame stabilization, and global structure of the burner-attached flame. Chemical explosive mode analysis (CEMA) shows that the entire windward shear layer, and a large region on the leeward side of the jet, are highly explosive prior to ignition and are dominated by non-premixed flame structures after

Vanadium-rich tourmaline from graphitic rocks at Bítovánky, Czech republic; compositional variation, crystal structure

Czech Academy of Sciences Publication Activity Database

Cempírek, J.; Houzar, S.; Novák, M.; Selway, J.B.; Šrein, Vladimír

2006-01-01

Roč. 28, Spec. pap. (2006), s. 39-41 ISSN 1896-2203. [Central European Mineralogical Conference /1./. Vyšná Boca, 11.09.2006-15.09.2006] Institutional research plan: CEZ:AV0Z30460519 Keywords : V-rich tourmaline * compositional variation * crystal structure Subject RIV: DB - Geology ; Mineralogy

Rich structure in the correlation matrix spectra in non-equilibrium steady states.

Science.gov (United States)

Biswas, Soham; Leyvraz, Francois; Monroy Castillero, Paulino; Seligman, Thomas H

2017-01-17

It has been shown that, if a model displays long-range (power-law) spatial correlations, its equal-time correlation matrix will also have a power law tail in the distribution of its high-lying eigenvalues. The purpose of this paper is to show that the converse is generally incorrect: a power-law tail in the high-lying eigenvalues of the correlation matrix may exist even in the absence of equal-time power law correlations in the initial model. We may therefore view the study of the eigenvalue distribution of the correlation matrix as a more powerful tool than the study of spatial Correlations, one which may in fact uncover structure, that would otherwise not be apparent. Specifically, we show that in the Totally Asymmetric Simple Exclusion Process, whereas there are no clearly visible correlations in the steady state, the eigenvalues of its correlation matrix exhibit a rich structure which we describe in detail.

Internal spin structure of the nucleon

International Nuclear Information System (INIS)

Hughes, V.W.; Kuti, J.

1983-01-01

The study of the structure of the proton and neutron through deep inelastic scattering, initially with electrons but subsequently with muons and neutrinos as well, has played a central role in establishing the quark-parton theory of the composition of hadrons and of quantum chromodynamics (QCD). One important aspect of these theoretical and experimental developments is the two spin-dependent structure functions, which are independent of the two spin-averaged structure functions and define the internal spin structure of the nucleon. Since both quarks and gluons possess spin and the forces between them are spin dependent, we can expect important information on these forces and on nucleon structure to be obtained through the study of the spindependent aspects of the nucleon wave function, as has been the case before in atomic and nuclear physics

Structural and Chemical Evolution of Li- and Mn-rich Layered Cathode Material

Energy Technology Data Exchange (ETDEWEB)

Zheng, Jianming; Xu, Pinghong; Gu, Meng; Xiao, Jie; Browning, Nigel D.; Yan, Pengfei; Wang, Chong M.; Zhang, Jiguang

2015-02-24

Lithium (Li)- and manganese-rich (LMR) layered-structure materials are very promising cathodes for high energy density lithium-ion batteries. However, their voltage fading mechanism and its relationships with fundamental structural changes are far from being sufficiently understood. Here we report the detailed phase transformation pathway in the LMR cathode (Li[Li0.2Ni0.2Mn0.6]O2) during cycling for the samples prepared by hydro-thermal assistant method. It is found the transformation pathway of LMR cathode is closely correlated to its initial structure and preparation conditions. The results reveal that LMR cathode prepared by HA approach experiences a phase transformation from the layered structure to a LT-LiCoO2 type defect spinel-like structure (Fd-3m space group) and then to a disordered rock-salt structure (Fm-3m space group). The voltage fade can be well correlated with the Li ion insertion into octahedral sites, rather than tetrahedral sites, in both defect spinel-like structure and disordered rock-salt structure. The reversible Li insertion/removal into/from the disordered rock-salt structure is ascribed to the Li excess environment that can satisfy the Li percolating in the disordered rock-salt structure despite the increased kinetic barrier. Meanwhile, because of the presence of a great amount of oxygen vacancies, a significant decrease of Mn valence is detected in the cycled particle, which is below that anticipated for a potentially damaging Jahn-Teller distortion (+3.5). Clarification of the phase transformation pathway, cation redistribution, oxygen vacancy and Mn valence change undoubtedly provides insights into a profound understanding on the voltage fade, and capacity degradation of LMR cathode. The results also inspire us to further enhance the reversibility of LMR cathode via improving its surface structural stability.

MOTIVATION INTERNALIZATION AND SIMPLEX STRUCTURE IN SELF-DETERMINATION THEORY.

Science.gov (United States)

Ünlü, Ali; Dettweiler, Ulrich

2015-12-01

Self-determination theory, as proposed by Deci and Ryan, postulated different types of motivation regulation. As to the introjected and identified regulation of extrinsic motivation, their internalizations were described as "somewhat external" and "somewhat internal" and remained undetermined in the theory. This paper introduces a constrained regression analysis that allows these vaguely expressed motivations to be estimated in an "optimal" manner, in any given empirical context. The approach was even generalized and applied for simplex structure analysis in self-determination theory. The technique was exemplified with an empirical study comparing science teaching in a classical school class versus an expeditionary outdoor program. Based on a sample of 84 German pupils (43 girls, 41 boys, 10 to 12 years old), data were collected using the German version of the Academic Self-Regulation Questionnaire. The science-teaching format was seen to not influence the pupils' internalization of identified regulation. The internalization of introjected regulation differed and shifted more toward the external pole in the outdoor teaching format. The quantification approach supported the simplex structure of self-determination theory, whereas correlations may disconfirm the simplex structure.

Summer Ephemeroptera, Plecoptera, and Trichoptera (EPT) species richness and community structure in the lower Illinois River basin of Illinois

Science.gov (United States)

DeWalt, R.E.; Webb, D.W.; Harris, M.A.

1999-01-01

Ephemeroptera, Plecoptera, and Trichoptera (EPT) species richness is useful for monitoring stream health, but no published studies in Illinois quantitatively document EPT richness or assemblage structure. The objectives of this study were to characterize adult EPT richness and structure and relate these to relative water quality at eight stream sites (160-69,300 km3 area) in the lower Illinois River basin. Adults were ultra-violet light trapped in June, July, and August 1997. Nutrient enrichment by nitrate and nitrite nitrogen was strongly evident, especially in smaller drainages, while critical loss of stable habitat was observed in larger water bodies. Seventy EPT species were identified from 17,889 specimens. Trichoptera were by far the most speciose (41 species), followed by Ephemeroptera (26), and Plecoptera (3). Caddisflies also dominated species richness across sites, contributing 18.0 of the average 28.9 total EPT species collected. Site EPT richness varied significantly (F = 5.51, p = 0.003, df = 7), with smaller drainages supporting greater richness, generally. Differences were also evident for months (F = 21.7, p = 0.0001, df = 2), with June being lower (11.8 average) than either July (20.6) or August (18.1) values. Hilsenhoff biotic index (HBI) scores did not vary significantly across sites (F = 0.7, p = 0.7, df = 7), but were different across months (F = 5.4, p = 0.02, df = 2). June (4.23) and July (4.53) means were not different, but both were lower (of better quality) than August (5.33) scores. The relationship of EPT to HBI scores was not investigated statistically due to problems of sample size and interdependence of monthly samples, but graphical analysis suggested no consistent relationship. This suggested a decoupling of the HBI from the EPT and implied that the gain in taxonomic resolution achieved by using adults outstripped the resolution of the HBI. Use of the HBI to characterize adult aquatic insect communities is discouraged. New state

Structural Analyses of Phase Stability in Amorphous and Partially Crystallized Ge-Rich GeTe Films Prepared by Atomic Layer Deposition.

Science.gov (United States)

Gwon, Taehong; Mohamed, Ahmed Yousef; Yoo, Chanyoung; Park, Eui-Sang; Kim, Sanggyun; Yoo, Sijung; Lee, Han-Koo; Cho, Deok-Yong; Hwang, Cheol Seong

2017-11-29

The local bonding structures of Ge x Te 1-x (x = 0.5, 0.6, and 0.7) films prepared through atomic layer deposition (ALD) with Ge(N(Si(CH 3 ) 3 ) 2 ) 2 and ((CH 3 ) 3 Si) 2 Te precursors were investigated using Ge K-edge X-ray absorption spectroscopy (XAS). The results of the X-ray absorption fine structure analyses show that for all of the compositions, the as-grown films were amorphous with a tetrahedral Ge coordination of a mixture of Ge-Te and Ge-Ge bonds but without any signature of Ge-GeTe decomposition. The compositional evolution in the valence band electronic structures probed through X-ray photoelectron spectroscopy suggests a substantial chemical influence of additional Ge on the nonstoichiometric GeTe. This implies that the ALD process can stabilize Ge-abundant bonding networks like -Te-Ge-Ge-Te- in amorphous GeTe. Meanwhile, the XAS results on the Ge-rich films that had undergone post-deposition annealing at 350 °C show that the parts of the crystalline Ge-rich GeTe became separated into Ge crystallites and rhombohedral GeTe in accordance with the bulk phase diagram, whereas the disordered GeTe domains still remained, consistent with the observations of transmission electron microscopy and Raman spectroscopy. Therefore, amorphousness in GeTe may be essential for the nonsegregated Ge-rich phases and the low growth temperature of the ALD enables the achievement of the structurally metastable phases.

Structural and functional characterization of EIAV gp45 fusion peptide proximal region and asparagine-rich layer

Energy Technology Data Exchange (ETDEWEB)

Duan, Liangwei; Du, Jiansen [State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071 (China); Wang, Xuefeng; Zhou, Jianhua; Wang, Xiaojun [State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001 (China); Liu, Xinqi, E-mail: liu2008@nankai.edu.cn [State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071 (China)

2016-04-15

Equine infectious anaemia virus (EIAV) and human immunodeficiency virus (HIV) are members of the lentiviral genus. Similar to HIV gp41, EIAV gp45 is a fusogenic protein that mediates fusion between the viral particle and the host cell membrane. The crystal structure of gp45 reported reveals a different conformation in the here that includes the fusion peptide proximal region (FPPR) and neighboring asparagine-rich layer compared with previous HIV-1 gp41 structures. A complicated hydrogen-bond network containing a cluster of solvent molecules appears to be critical for the stability of the gp45 helical bundle. Interestingly, viral replication was relatively unaffected by site-directed mutagenesis of EIAV, in striking contrast to that of HIV-1. Based on these observations, we speculate that EIAV is more adaptable to emergent mutations, which might be important for the evolution of EIAV as a quasi-species, and could potentially contribute to the success of the EIAV vaccine. - Highlights: • The crystal structure of EIAV gp45 was determined. • The fusion peptide proximal region adopts a novel conformation different to HIV-1. • The asparagine-rich layer includes an extensive hydrogen-bond network. • These regions of EIAV are highly tolerant to mutations. • The results provide insight into the mechanism of gp41/gp45-mediated membrane fusion.

High-spin structure of neutron-rich Dy isotopes

Indian Academy of Sciences (India)

Neutron-rich Dy isotopes; high-spin states; g-factors; cranked HFB theory. ... for 164Dy marking a clear separation in the behaviour as a function of neutron ... cipal x-axis as the cranking axis) in this mass region we have planned to make a sys-.

Draft I.E.C. standard for monitoring PWR internal structures; Projet de norme C.E.I. pour la surveillance des structures internes des REP

Energy Technology Data Exchange (ETDEWEB)

Trenty, A.

1994-06-01

EDF has proposed to the International Electrotechnical Commission a draft standard for monitoring the vessel internal structures of PWRs. The standard applies to systems used for monitoring the vibratory behavior of the internal structures of PWRs (core barrel, thermal shield, fuel assemblies) on the basis of neutron fluctuations observed outside the vessel as well as of vessel vibrations. It covers the systems characteristics and the monitoring procedures. It should facilitate standardization of monitoring and comparisons on an international level. This paper presents the main features of the draft standard: -principles of measurement: correlation between movements of internals and ex core neutron noise on the one hand, forced vibrations of the vessel on the other hand; -sampling and conditioning of the signals; -monitoring equipment and in particular spectral analysis device; -functions of the monitoring software used for spectral analysis, peak detection and calculation of structure displacement; -studies preliminary to setting up the monitoring (calculation of internal vibratory modes, defect simulation on mockup, qualification on reactor during hot test...); -monitoring procedures (periodicity of analysis and what to do in case of anomaly); -documentation necessary to the monitoring. A diagnostic procedure is given as an example. The draft standard, written in 1994, will be presented in Frankfurt (Germany) in February 1995. (author). 1 annexe.

Structural evolution of Ge-rich Si1−xGex films deposited by jet-ICPCVD

Directory of Open Access Journals (Sweden)

Yu Wang

2015-11-01

Full Text Available Amorphous Ge-rich Si1−xGex films with local Ge-clustering were deposited by dual-source jet-type inductively coupled plasma chemical-vapor deposition (jet-ICPCVD. The structural evolution of the deposited films annealed at various temperatures (Ta is investigated. Experimental results indicate that the crystallization occurs to form Ge and Si clusters as Ta = 500 °C. With raising Ta up to 900 °C, Ge clusters percolate together and Si diffuses and redistributes to form a Ge/SiGe core/shell structure, and some Ge atoms partially diffuse to the surface as a result of segregation. The present work will be helpful in understanding the structural evolution process of a hybrid SiGe films and beneficial for further optimizing the microstructure and properties.

Corporate strategy and the organizational structure of companies in international business

Directory of Open Access Journals (Sweden)

Aleksić Ana

2004-01-01

Full Text Available The aim of this paper is to illuminate the importance of corporate strategy and organizational structure as crucial variables for successful international business. We wanted to point out that companies, in order to exploit opportunities in international environment, must develop a high level of consent between the applied strategy and the model of organizational structure. Today all organizations, no matter how big they are, are affected by the international environment and its management must consider very carefully the benefits and costs of alternative strategies and the corresponding models of organizational structure.

The Evolution and Internal Structure of Jupiter and Saturn with Compositional Gradients

NARCIS (Netherlands)

Vazan, A.; Helled, R.; Podolak, M.; Kovetz, A.

2016-01-01

The internal structure of gas giant planets may be more complex than the commonly assumed core-envelope structure with an adiabatic temperature profile. Different primordial internal structures as well as various physical processes can lead to non-homogenous compositional distributions. A

Structures of pseudechetoxin and pseudecin, two snake-venom cysteine-rich secretory proteins that target cyclic nucleotide-gated ion channels: implications for movement of the C-terminal cysteine-rich domain

International Nuclear Information System (INIS)

Suzuki, Nobuhiro; Yamazaki, Yasuo; Brown, R. Lane; Fujimoto, Zui; Morita, Takashi; Mizuno, Hiroshi

2008-01-01

The structures of pseudechetoxin and pseudecin suggest that both proteins bind to cyclic nucleotide-gated ion channels in a manner in which the concave surface occludes the pore entrance. Cyclic nucleotide-gated (CNG) ion channels play pivotal roles in sensory transduction by retinal photoreceptors and olfactory neurons. The elapid snake toxins pseudechetoxin (PsTx) and pseudecin (Pdc) are the only known protein blockers of CNG channels. These toxins belong to a cysteine-rich secretory protein (CRISP) family containing an N-terminal pathogenesis-related proteins of group 1 (PR-1) domain and a C-terminal cysteine-rich domain (CRD). PsTx and Pdc are highly homologous proteins, but their blocking affinities on CNG channels are different: PsTx blocks both the olfactory and retinal channels with ∼15–30-fold higher affinity than Pdc. To gain further insights into their structure and function, the crystal structures of PsTx, Pdc and Zn 2+ -bound Pdc were determined. The structures revealed that most of the amino-acid-residue differences between PsTx and Pdc are located around the concave surface formed between the PR-1 domain and the CRD, suggesting that the concave surface is functionally important for CNG-channel binding and inhibition. A structural comparison in the presence and absence of Zn 2+ ion demonstrated that the concave surface can open and close owing to movement of the CRD upon Zn 2+ binding. The data suggest that PsTx and Pdc occlude the pore entrance and that the dynamic motion of the concave surface facilitates interaction with the CNG channels

Structures of pseudechetoxin and pseudecin, two snake-venom cysteine-rich secretory proteins that target cyclic nucleotide-gated ion channels: implications for movement of the C-terminal cysteine-rich domain

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Nobuhiro [Department of Applied Biochemistry, University of Tsukuba, Tsukuba, Ibaraki 305-8572 (Japan); Department of Biochemistry, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602 (Japan); Yamazaki, Yasuo [Department of Biochemistry, Meiji Pharmaceutical University, Kiyose, Tokyo 204-8588 (Japan); Brown, R. Lane [Neurological Science Institute, Oregon Health and Science University, Beaverton, Oregon 97006 (United States); Fujimoto, Zui [Department of Biochemistry, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602 (Japan); Morita, Takashi, E-mail: tmorita@my-pharm.ac.jp [Department of Biochemistry, Meiji Pharmaceutical University, Kiyose, Tokyo 204-8588 (Japan); Mizuno, Hiroshi, E-mail: tmorita@my-pharm.ac.jp [Department of Biochemistry, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602 (Japan); VALWAY Technology Center, NEC Soft Ltd, Koto-ku, Tokyo 136-8627 (Japan); Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology, Central 6, Tsukuba, Ibaraki 305-8566 (Japan); Department of Applied Biochemistry, University of Tsukuba, Tsukuba, Ibaraki 305-8572 (Japan)

2008-10-01

The structures of pseudechetoxin and pseudecin suggest that both proteins bind to cyclic nucleotide-gated ion channels in a manner in which the concave surface occludes the pore entrance. Cyclic nucleotide-gated (CNG) ion channels play pivotal roles in sensory transduction by retinal photoreceptors and olfactory neurons. The elapid snake toxins pseudechetoxin (PsTx) and pseudecin (Pdc) are the only known protein blockers of CNG channels. These toxins belong to a cysteine-rich secretory protein (CRISP) family containing an N-terminal pathogenesis-related proteins of group 1 (PR-1) domain and a C-terminal cysteine-rich domain (CRD). PsTx and Pdc are highly homologous proteins, but their blocking affinities on CNG channels are different: PsTx blocks both the olfactory and retinal channels with ∼15–30-fold higher affinity than Pdc. To gain further insights into their structure and function, the crystal structures of PsTx, Pdc and Zn{sup 2+}-bound Pdc were determined. The structures revealed that most of the amino-acid-residue differences between PsTx and Pdc are located around the concave surface formed between the PR-1 domain and the CRD, suggesting that the concave surface is functionally important for CNG-channel binding and inhibition. A structural comparison in the presence and absence of Zn{sup 2+} ion demonstrated that the concave surface can open and close owing to movement of the CRD upon Zn{sup 2+} binding. The data suggest that PsTx and Pdc occlude the pore entrance and that the dynamic motion of the concave surface facilitates interaction with the CNG channels.

Is torrefaction of polysaccharides-rich biomass equivalent to carbonization of lignin-rich biomass?

Science.gov (United States)

Bilgic, E; Yaman, S; Haykiri-Acma, H; Kucukbayrak, S

2016-01-01

Waste biomass species such as lignin-rich hazelnut shell (HS) and polysaccharides-rich sunflower seed shell (SSS) were subjected to torrefaction at 300°C and carbonization at 600°C under nitrogen. The structural variations in torrefied and carbonized biomasses were compared. Also, the burning characteristics under dry air and pure oxygen (oxy-combustion) conditions were investigated. It was concluded that the effects of carbonization on HS are almost comparable with the effects of torrefaction on SSS in terms of devolatilization and deoxygenation potentials and the increases in carbon content and the heating value. Consequently, it can be proposed that torrefaction does not provide efficient devolatilization from the lignin-rich biomass while it is relatively more efficient for polysaccharides-rich biomass. Heat-induced variations in biomass led to significant changes in the burning characteristics under both burning conditions. That is, low temperature reactivity of biomass reduced considerably and the burning shifted to higher temperatures with very high burning rates. Copyright © 2015 Elsevier Ltd. All rights reserved.

International conference on design, fabrication and economy of metal structures

CERN Document Server

Farkas, József

2013-01-01

These are the proceedings of the International Conference on Design, Fabrication and Economy of Metal Structures held on 24-26 April 2013 in Miskolc, Hungary which contain 99 papers covering: Structural optimization Thin-walled structures Stability Fatigue Frames Fire Fabrication Welding technology Applications Steel-concrete composite Special problems The authors are from 23 different countries, ensuring that the themes covered are of worldwide interest and importance. The International Institute of Welding (IIW), the International Society of Structural and Multidisciplinary Optimization (ISSMO), the TÁMOP 4.2.1.B-10/2/KONV-2010-0001 project entitled “Increasing the quality of higher education through the development of research - development and innovation program at the University of Miskolc supported by the European Union, co-financed by the European Social Fund” and many other sponsors helped organizers to collect these valuable studies, the results of which will provoke discussion, and provide an i...

Evaluation of CANDU NPP containment structure subjected to aging and internal pressure increase

Energy Technology Data Exchange (ETDEWEB)

Huang, Xu [Department of Civil Engineering, University of Toronto, Toronto M5S 1A4 (Canada); Kwon, Oh-Sung, E-mail: os.kwon@utoronto.ca [Department of Civil Engineering, University of Toronto, Toronto M5S 1A4 (Canada); Bentz, Evan [Department of Civil Engineering, University of Toronto, Toronto M5S 1A4 (Canada); Tcherner, Julia [Candu Energy Inc. a member of SNC-Lavalin Group, Mississauga L5K 1B1 (Canada)

2017-04-01

Highlights: • The aging effects on the performance of a nuclear containment structure is evaluated. • A numerical model of the structure is subjected to increasing internal pressure. • No through-thickness cracks are predicted under the design level internal pressure. • The structure is predicted to be ductile up to large internal pressure levels. - Abstract: The objective of this study is to investigate the long-term performance of a typical CANDU® containment structure. A three-dimensional nonlinear finite element model was built to realistically evaluate the performance of the structure under service load as well as a hypothetical beyond-design level internal pressure. Consideration is given to the time-dependent effects, such as shrinkage, creep, and relaxation of prestressing tendons, over a 60-year timeframe. In addition, the sensitivity of the response of the containment structure against support condition, internal temperature profile and temporary construction openings was also investigated. The accuracy of the numerical model was validated against structural measurements made during a routine leak rate test. The analysis results show that the containment structure would develop a ductile mechanism if the internal pressure significantly exceeded the design pressure. The pressure-deformation relationship of the structure is sensitive to the considered time-dependent parameters.

Structure of Se-rich As-Se glasses by high-resolution x-ray photoelectron spectroscopy

International Nuclear Information System (INIS)

Golovchak, R.; Kovalskiy, A.; Miller, A. C.; Jain, H.; Shpotyuk, O.

2007-01-01

To establish the validity of various proposed structural models, we have investigated the structure of the binary As x Se 100-x chalcogenide glass family (x≤40) by high-resolution x-ray photoelectron spectroscopy. From the composition dependence of the valence band, the contributions to the density of states from the 4p lone pair electrons of Se and the 4p bonding states and 4s electrons of Se and As are identified in the top part of the band. The analysis of Se 3d and As 3d core-level spectra supports the so-called chain crossing model for the atomic structure of Se-rich As x Se 100-x bulk glasses. The results also indicate small deviations (∼3-8%) from this model, especially for glass compositions with short Se chains (25 40 Se 60 and of Se-Se-Se fragments in a glass with composition x=30 is established

Rotational Spectrum of 1,1-Difluoroethane: Internal Rotation Analysis and Structure

Science.gov (United States)

Villamanan, R. M.; Chen, W. D.; Wlodarczak, G.; Demaison, J.; Lesarri, A. G.; Lopez, J. C.; Alonso, J. L.

1995-05-01

The rotational spectrum of CH3CHF2 in its ground state was measured up to 653 GHz. Accurate rotational and centrifugal distortion constants were determined. The internal rotation splittings were analyzed using the internal axis method. An ab initio structure has been calculated and a near-equilibrium structure has been estimated using offsets derived empirically. This structure was compared to an experimental r0 structure. The four lowest excited states (including the methyl torsion) have also been assigned.

Electronic structure and fine structural features of the air-grown UNxOy on nitrogen-rich uranium nitride

Science.gov (United States)

Long, Zhong; Zeng, Rongguang; Hu, Yin; Liu, Jing; Wang, Wenyuan; Zhao, Yawen; Luo, Zhipeng; Bai, Bin; Wang, Xiaofang; Liu, Kezhao

2018-06-01

Oxide formation on surface of nitrogen-rich uranium nitride film/particles was investigated using X-ray photoelectron spectroscopy (XPS), auger electron spectroscopy (AES), aberration-corrected transmission electron microscopy (TEM), and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) coupled with electron energy-loss spectroscopy (EELS). XPS and AES studies indicated that the oxidized layer on UN2-x film is ternary compound uranium oxynitride (UNxOy) in 5-10 nm thickness. TEM/HAADF-STEM and EELS studies revealed the UNxOy crystallizes in the FCC CaF2-type structure with the lattice parameter close to the CaF2-type UN2-x matrix. The work can provide further information to the oxidation mechanism of uranium nitride.

Structural studies on an internal loop from a hairpin ribozyme

Energy Technology Data Exchange (ETDEWEB)

Cai, Z.; SantaLucia, J. Jr.; Tinoco, I. Jr. [Univ. of California, Berkeley, CA (United States)

1994-12-01

Ribozymes, RNA enzymes, catalyze site-specific RNA cleavage and ligation reactions. We are studying the three-dimensional structure of a hairpin ribozyme derived from the minus strand of tobacco ring spot virus satellite RNA ((-)sTRSV), which has been engineering to specifically cleave the HIV-1 RNA. The minimum structure for the catalytic reaction involves a 50-nucleotide ribozyme and a 14-nucleotide substrate. The proposed secondary structure of the ribozyme-substrate complex consists of four short helices separated by two internal loops. The relatively large size (64-nucleotide) of the ribozyme-substrate complex presents formidable problems in solving the structure using NMR. Therefore we are studying smaller structural subunits of the complex. We are determining the high resolution structure of the symmetric internal loop involving the cleavage site and the flanking helices. One strand of the internal loop was selectively {sup 13}C-labeled at C8 of each purine and C6 of each pyrimidine. By using {sup 13}C-edited two-dimensional NMR, the proton NOESY spectrum was greatly simplified. This allowed unambiguous sequential proton resonance assignments along each strand. Three-dimensional {sup 1}-{sup 13}C HMQC-NOESY was used to further facilitate resonance assignments. We are also enzymatically synthesizing the entire 50-nucleotide ribozyme and will combine it with the {sup 13}C-labeled substrate. Through comparison of the NOE connectivities of the labeled nucleotides from the internal loop alone with those from the entire complex, the differences between the two structures can be elucidated.

Capital Flight and Transfer from Resource-Rich Developing Countries

OpenAIRE

Demachi, Kazue

2013-01-01

This paper analyzes the influence of international resource price movements on capital outflows from resource-rich developing countries (RRDCs) by distinguishing capital flight and capital transfers. The volume of capital flight and transfers are calculated and their determinants are analyzed using macro-panel data constituting 21 resource-rich developing countries from 1990 to 2011. Through the regression analysis, the linkage between capital flight and resource revenue as well as that betwe...

Consequences of buffelgrass pasture development for primary productivity, perennial plant richness, and vegetation structure in the drylands of Sonora, Mexico.

Science.gov (United States)

Franklin, Kimberly; Molina-Freaner, Francisco

2010-12-01

In large parts of northern Mexico native plant communities are being converted to non-native buffelgrass (Pennisetum ciliare) pastures, and this conversion could fundamentally alter primary productivity and species richness. In Sonora, Mexico land conversion is occurring at a regional scale along a rainfall-driven gradient of primary productivity, across which native plant communities transition from desert scrub to thorn scrub. We used a paired sampling design to compare a satellite-derived index of primary productivity, richness of perennial plant species, and canopy-height profiles of native plant communities with buffelgrass pastures. We sampled species richness across a gradient of primary productivity in desert scrub and thorn scrub vegetation to examine the influence of site productivity on the outcomes of land conversion. We also examined the influence of pasture age on species richness of perennial plants. Index values of primary productivity were lower in buffelgrass pastures than in native vegetation, which suggests a reduction in primary productivity. Land conversion reduced species richness by approximately 50% at local and regional scales, reduced tree and shrub cover by 78%, and reduced canopy height. Land conversion disproportionately reduced shrub species richness, which reflects the common practice among Sonoran ranchers of conserving certain tree and cactus species. Site productivity did not affect the outcomes of land conversion. The age of a buffelgrass pasture was unrelated to species richness within the pasture, which suggests that passive recovery of species richness to preconversion levels is unlikely. Our findings demonstrate that land conversion can result in large losses of plant species richness at local and regional scales and in substantial changes to primary productivity and vegetation structure, which casts doubt on the feasibility of restoring native plant communities without active intervention on the part of land managers. �

Crystal structure of modular sodium-rich and low-iron eudialyte from Lovozero alkaline massif

Energy Technology Data Exchange (ETDEWEB)

Rozenberg, K. A.; Rastsvetaeva, R. K., E-mail: rast@ns.crys.ras.ru; Aksenov, S. M. [Federal Scientific Research Center “Crystallography and Photonics”, Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

2016-09-15

The structure of the sodium-rich representative of the eudialyte group found by A.P. Khomyakov at the Lovozero massif (Kola Peninsula) is studied by X-ray diffraction. The trigonal cell parameters are: a = 14.2032(1) and c = 60.612(1) Å, V = 10589.13 Å3, space group R3m. The structure is refined to the final R = 5.0% in the anisotropic approximation of atomic displacement parameters using 3742|F| > 3σ(F). The idealized formula (Z = 3) is Na{sub 37}Ca{sub 10}Mn{sub 2}FeZr{sub 6}Si{sub 50}(Ti, Nb){sub 2}O{sub 144}(OH){sub 5}Cl{sub 3} · H{sub 2}O. Like other 24-layer minerals of the eudialyte group, this mineral has a modular structure. Its structure contains two modules, namely, “alluaivite” (with an admixture of “eudialyte”) and “kentbrooksite,” called according to the main structural fragments of alluaivite, eudialyte, and kentbrooksite. The mineral found at the Lovozero alkaline massif shows some chemical and symmetry-structural distinctions from the close-in-composition labyrinthite modular mineral from the Khibiny massif. The difference between the minerals stems from different geochemical conditions of mineral formation in the two regions.

Multiscale pore structure and its effect on gas transport in organic-rich shale

Science.gov (United States)

Wu, Tianhao; Li, Xiang; Zhao, Junliang; Zhang, Dongxiao

2017-07-01

A systematic investigation of multiscale pore structure in organic-rich shale by means of the combination of various imaging techniques is presented, including the state-of-the-art Helium-Ion-Microscope (HIM). The study achieves insight into the major features at each scale and suggests the affordable techniques for specific objectives from the aspects of resolution, dimension, and cost. The pores, which appear to be isolated, are connected by smaller pores resolved by higher-resolution imaging. This observation provides valuable information, from the microscopic perspective of pore structure, for understanding how gas accumulates and transports from where it is generated. A comprehensive workflow is proposed based on the characteristics acquired from the multiscale pore structure analysis to simulate the gas transport process. The simulations are completed with three levels: the microscopic mechanisms should be taken into consideration at level I; the spatial distribution features of organic matter, inorganic matter, and macropores constitute the major issue at level II; and the microfracture orientation and topological structure are dominant factors at level III. The results of apparent permeability from simulations agree well with the values acquired from experiments. By means of the workflow, the impact of various gas transport mechanisms at different scales can be investigated more individually and precisely than conventional experiments.

Structural and Infrastructural Underpinnings of International R&D Networks

DEFF Research Database (Denmark)

Niang, Mohamed; Sørensen, Brian Vejrum

2009-01-01

This paper explores the process of globally distributing R&D activities with an emphasis on the effects of network maturity. It discusses emerging configurations by asking how the structure and infrastructure of international R&D networks evolve along with the move from a strong R&D center...... to dispersed development. Drawing from case studies of two international R&D networks, it presents a capability maturity model and argues that understanding the interaction between new structures and infrastructures of the dispersed networks has become a key requirement for developing organizational...

Analyzing the Structure of the International Business Curriculum in India

Science.gov (United States)

Srivastava, Deepak K.

2012-01-01

This article analyzes the structure of the international business curriculum through a questionnaire-based survey among current students and young managers who are studying or have studied international business courses in one of the top B-Schools of India. Respondents have the opinion that international business is more than internationalization…

Comparing apples with oranges: revisiting the gender wage gap in an international perspective

OpenAIRE

Robert Plasman; Salimata Sissoko Ndeye

2005-01-01

Using a rich and comparable micro-data set, we analyse international differences in gender pay gaps in the private sector for a sample of five European economies: Belgium, Denmark, Ireland, Italy and Spain. Using different methods, we examine how wage structure, differences in the distribution of measured characteristics, occupational and industrial segregation contribute to explain the pattern of international differences. Furthermore, we take into account indirect discrimination influencing...

Vascular epiphytes of the Atlantic Forest in the Sinos River basin, state of Rio Grande do Sul, Brazil: richness, floristic composition and community structure.

Science.gov (United States)

Barbosa, M D; Becker, D F P; Cunha, S; Droste, A; Schmitt, J L

2015-05-01

The Atlantic Forest, which has a vast epiphytic richness, is a priority area for preservation, listed as one of the five most important world hotspots. Vascular epiphyte richness, composition and community structure were studied in two fragments, one of the ombrophilous (29º43'42"S and 50º22'00"W) and the other of the seasonal (29º40'54"S and 51º06'56"W) forest, both belonging to the Atlantic Forest biome in the Sinos River basin, Rio Grande do Sul, Brazil. In each fragment, 40 trees, divided into four ecological zones, were analyzed. In each zone, the occurrence of the species was recorded, and the importance value of each species was calculated according to the frequency of phorophytes and intervals, and cover scores. The Shannon index was calculated for the two communities. In the fragment of the ombrophilous forest (F1), 30 epiphytic species were recorded, and in the seasonal forest (F2), 25. The highest importance value was found for Microgramma squamulosa (Kaulf.) de la Sota in both fragments. The diversity indexes for F1 (H'=2.72) and F2 (H'=2.55) were similar and reflected the subtropical location of the areas. The decrease in mean richness in both fragments in zone 3 (internal crown) to zone 4 (external crown) may be associated with time and space availability for epiphyte occupation and microclimate variations. Exclusive species were found in the areas, which suggest that a greater number of preserved fragments may result in a greater number of preserved epiphytic species in the Sinos River basin.

Neutron rich nuclei around 132Sn

International Nuclear Information System (INIS)

Bhattacharya, Sarmishtha

2016-01-01

The neutron rich nuclei with few particles or holes in 132 Sn have various experimental and theoretical interest to understand the evolution of nuclear structure around the doubly magic shell closure Z=50 and N=82. Some of the exotic neutron rich nuclei in this mass region are situated near waiting points in the r-process path and are of special astrophysical interest. Neutron rich nuclei near 132 Sn have been studied using fission fragment spectroscopy. The lifetime of low lying isomeric states have been precisely measured and the beta decay from the ground and isomeric states have been characterized using gamma-ray spectroscopy

Global assemblages and structural models of International Relations

DEFF Research Database (Denmark)

Corry, Olaf

2014-01-01

-category of assemblages – those constructed as malleable and governable which I call ‘governance-objects’ – is central to structure in international relations. The chapter begins with standard definitions of what structures are – patterns of interaction between elements – and briefly covers the range of models currently...... used to simplify different structures. Next the chapter points to the blindness of most structural theories of IR to the role of assemblages in general and governance-objects in particular. Thirdly, the idea that a polity is constituted precisely by the assemblage of a governance...

Purification, structure and immunobiological activity of an arabinan-rich pectic polysaccharide from the cell walls of Prunus dulcis seeds.

Science.gov (United States)

Dourado, Fernando; Madureira, Pedro; Carvalho, Vera; Coelho, Ricardo; Coimbra, Manuel A; Vilanova, Manuel; Mota, Manuel; Gama, Francisco M

2004-10-20

The structure and bioactivity of a polysaccharide extracted and purified from a 4M KOH + H3BO3 solution from Prunus dulcis seed cell wall material was studied. Anion-exchange chromatography of the crude extract yielded two sugar-rich fractions: one neutral (A), the other acidic (E). These fractions contain a very similar monosaccharide composition: 5:2:1 for arabinose, uronic acids and xylose, respectively, rhamnose and galactose being present in smaller amounts. As estimated by size-exclusion chromatography, the acidic fraction had an apparent molecular mass of 762 kDa. Methylation analysis (from the crude and fractions A and E), suggests that the polysaccharide is an arabinan-rich pectin. In all cases, the polysaccharides bear the same type of structural Ara moieties with highly branched arabinan-rich pectic polysaccharides. The average relative proportions of the arabinosyl linkages is 3:2:1:1 for T-Araf:(1-->5)-Araf:(1-->3,5)-Araf:(1-->2,3,5)-Araf. The crude polysaccharide extract and fractions A and E induced a murine lymphocyte stimulatory effect, as evaluated by the in vitro and in vivo expression of lymphocyte activation markers and spleen mononuclear cells culture proliferation. The lymphocyte stimulatory effect was stronger on B- than on T-cells. No evidence of cytotoxic effects induced by the polysaccharide fractions was found.

Hydrocarbon-Rich Territories in Central Asia: Producing Countries, Exporting Enclaves or Transit Countries?

Directory of Open Access Journals (Sweden)

Aurelia Mañé

2005-10-01

Full Text Available This article aims to qualify the different analyses and currents of opinion that are circulating with respect to Central Asia’s capacity to become one of the main exporters of hydrocarbons in the next decade. For this, it first examines whether or not, in quantitativeterms, the hydrocarbon-rich territories of Central Asia can become one of the main suppliers on a world scale; secondly, it explains why the countries of Central Asia will play a necessarily different role on the international energy scene than that played by the OPEC countries; and, finally, it indicates what the relevance of this area could be in the organisation (structure of the contemporary international energy scene. In this sense, it discusses not producing countries, but rather countries of passage.

Adjustable internal structure for reconstructing gradient index profile of crystalline lens.

Science.gov (United States)

Bahrami, Mehdi; Goncharov, Alexander V; Pierscionek, Barbara K

2014-03-01

Employing advanced technologies in studying the crystalline lens of the eye has improved our understanding of the refractive index gradient of the lens. Reconstructing and studying such a complex structure requires models with adaptable internal geometry that can be altered to simulate geometrical and optical changes of the lens with aging. In this Letter, we introduce an optically well-defined, geometrical structure for modeling the gradient refractive index profile of the crystalline lens with the advantage of an adjustable internal structure that is not available with existing models. The refractive index profile assigned to this rotationally symmetric geometry is calculated numerically, yet it is shown that this does not limit the model. The study provides a basis for developing lens models with sophisticated external and internal structures without the need for analytical solutions to calculate refractive index profiles.

Are carnivore digestive separation mechanisms revealed on structure-rich diets?: Faecal inconsistency in dogs (Canis familiaris) fed day old chicks

NARCIS (Netherlands)

Cuyper, De Annelies; Clauss, M.; Hesta, Myriam; Cools, An; Bosch, G.; Hendriks, W.H.; Janssens, Geert P.J.

2018-01-01

Pronounced variations in faecal consistency have been described anecdotally for some carnivore species fed a structure-rich diet. Typically two faecal consistencies are distinguished, namely hard and firm versus liquid and viscous faeces. It is possible that a separation mechanism is operating in

Developmental programming of aortic and renal structure in offspring of rats fed fat-rich diets in pregnancy

DEFF Research Database (Denmark)

Armitage, James A.; Lakasing, Lorin; Taylor, Paul D.

2005-01-01

Evidence from human and animal studies suggests that maternal nutrition can induce developmental programming of adult hypertension in offspring. We have previously described a model of maternal dietary imbalance in Sprague-Dawley rats whereby administration of a maternal diet rich in animal lard......-Dawley rats fed a control diet (OC) or lard-rich diet (OHF) during pregnancy and suckling followed by a control diet post-weaning. To gain further insight, we assessed aortic reactivity and elasticity in an organ bath preparation and renal renin and Na+,K+-ATPase activity. Plasma aldosterone concentration...... weight, glomerular number or volume in OHF compared with OC, but renin and Na+,K+-ATPase activity were significantly reduced in OHF compared with controls. Programmed alterations to aortic structure and function are consistent with previous observations that exposure to maternal high fat diets produces...

Properties of neutron-rich nuclei studied by fission product nuclear chemistry

International Nuclear Information System (INIS)

Meyer, R.A.; Henry, E.A.; Griffin, H.C.; Lien, O.G. III; Lane, S.M.; Stevenson, P.C.; Yaffe, R.P.; Skarnemark, G.

1979-09-01

A review is given of the properties of neutron-rich nuclei studied by fission product nuclear chemistry and includes the techniques used in elemental isolation and current research on the structure of nuclei near 132 Sn, particle emission, and coexisting structure in both neutron-poor and neutron-rich nuclei. 35 references

Proceedings of the Third International Workshop on Jointed Structures.

Energy Technology Data Exchange (ETDEWEB)

Starr, Michael James; Brake, Matthew Robert; Segalman, Daniel Joseph; Bergman, Lawrence A.; Ewins, David J.

2013-08-01

The Third International Workshop on Jointed Structures was held from August 16th to 17th, 2012, in Chicago Illinois, following the ASME 2012 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. Thirty two researchers from both the United States and international locations convened to discuss the recent progress of mechanical joints related research and associated efforts in addition to developing a roadmap for the challenges to be addressed over the next five to ten years. These proceedings from the workshop include the minutes of the discussions and follow up from the 2009 workshop [1], presentations, and outcomes of the workshop. Specifically, twelve challenges were formulated from the discussions at the workshop, which focus on developing a better understanding of uncertainty and variability in jointed structures, incorporating high fidelity models of joints in simulations that are tractable/efficient, motivating a new generation of researchers and funding agents as to the importance of joint mechanics research, and developing new insights into the physical phenomena that give rise to energy dissipation in jointed structures. The ultimate goal of these research efforts is to develop a predictive model of joint mechanics.

Abnormal rich club organization and functional brain dynamics in schizophrenia.

Science.gov (United States)

van den Heuvel, Martijn P; Sporns, Olaf; Collin, Guusje; Scheewe, Thomas; Mandl, René C W; Cahn, Wiepke; Goñi, Joaquín; Hulshoff Pol, Hilleke E; Kahn, René S

2013-08-01

The human brain forms a large-scale structural network of regions and interregional pathways. Recent studies have reported the existence of a selective set of highly central and interconnected hub regions that may play a crucial role in the brain's integrative processes, together forming a central backbone for global brain communication. Abnormal brain connectivity may have a key role in the pathophysiology of schizophrenia. To examine the structure of the rich club in schizophrenia and its role in global functional brain dynamics. Structural diffusion tensor imaging and resting-state functional magnetic resonance imaging were performed in patients with schizophrenia and matched healthy controls. Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, the Netherlands. Forty-eight patients and 45 healthy controls participated in the study. An independent replication data set of 41 patients and 51 healthy controls was included to replicate and validate significant findings. MAIN OUTCOME(S) AND MEASURES: Measures of rich club organization, connectivity density of rich club connections and connections linking peripheral regions to brain hubs, measures of global brain network efficiency, and measures of coupling between brain structure and functional dynamics. Rich club organization between high-degree hub nodes was significantly affected in patients, together with a reduced density of rich club connections predominantly comprising the white matter pathways that link the midline frontal, parietal, and insular hub regions. This reduction in rich club density was found to be associated with lower levels of global communication capacity, a relationship that was absent for other white matter pathways. In addition, patients had an increase in the strength of structural connectivity-functional connectivity coupling. Our findings provide novel biological evidence that schizophrenia is characterized by a selective

22 CFR 96.32 - Internal structure and oversight.

Science.gov (United States)

2010-04-01

... Accreditation and Approval Licensing and Corporate Governance § 96.32 Internal structure and oversight. (a) The... number of such other provider; and (3) The name, address, and phone number of any entity it uses or...

Structural landscape of the proline-rich domain of Sos1 nucleotide exchange factor.

Science.gov (United States)

McDonald, Caleb B; Bhat, Vikas; Kurouski, Dmitry; Mikles, David C; Deegan, Brian J; Seldeen, Kenneth L; Lednev, Igor K; Farooq, Amjad

2013-01-01

Despite its key role in mediating a plethora of cellular signaling cascades pertinent to health and disease, little is known about the structural landscape of the proline-rich (PR) domain of Sos1 guanine nucleotide exchange factor. Herein, using a battery of biophysical tools, we provide evidence that the PR domain of Sos1 is structurally disordered and adopts an extended random coil-like conformation in solution. Of particular interest is the observation that while chemical denaturation of PR domain results in the formation of a significant amount of polyproline II (PPII) helices, it has little or negligible effect on its overall size as measured by its hydrodynamic radius. Our data also show that the PR domain displays a highly dynamic conformational basin in agreement with the knowledge that the intrinsically unstructured proteins rapidly interconvert between an ensemble of conformations. Collectively, our study provides new insights into the conformational equilibrium of a key signaling molecule with important consequences on its physiological function. Copyright © 2013 Elsevier B.V. All rights reserved.

Structural, mechanical and corrosion studies of Cr-rich inclusions in 152 cladding of dissimilar metal weld joint

Science.gov (United States)

Li, Yifeng; Wang, Jianqiu; Han, En-Hou; Yang, Chengdong

2018-01-01

Cr-rich inclusions were discovered in 152 cladding at the inner wall of domestic dissimilar metal weld joint, and their morphologies, microstructures, mechanical properties and corrosion behaviors were systematically characterized by SEM, TEM, nanoindentation and FIB. The results indicate that the Cr-rich inclusions originate from large-size Cr particles in 152 welding electrode flux, and they are 50-150 μm in size in most cases, and there is a continuous transition zone of 2-5 μm in width between the Cr inclusion core and 152 cladding matrix, and the transition zone consists of Ni & Fe-rich dendritic austenite and Cr23C6 and Cr matrix. The transition zone has the highest nanoindentation hardness (7.66 GPa), which is much harder than the inclusion core (5.14 GPa) and 152 cladding (3.71 GPa). In-situ microscopic tensile tests show that cracks initialize preferentially in transition zone, and then propagate into the inclusion core, and creep further into 152 cladding after penetrating the core area. The inclusion core and its transition zone both share similar oxide film structure with nickel-base 152 cladding matrix in simulated primary water, while those two parts present better general corrosion resistance than 152 cladding matrix due to higher Cr concentration.

The International Trade Network: weighted network analysis and modelling

International Nuclear Information System (INIS)

Bhattacharya, K; Mukherjee, G; Manna, S S; Saramäki, J; Kaski, K

2008-01-01

Tools of the theory of critical phenomena, namely the scaling analysis and universality, are argued to be applicable to large complex web-like network structures. Using a detailed analysis of the real data of the International Trade Network we argue that the scaled link weight distribution has an approximate log-normal distribution which remains robust over a period of 53 years. Another universal feature is observed in the power-law growth of the trade strength with gross domestic product, the exponent being similar for all countries. Using the 'rich-club' coefficient measure of the weighted networks it has been shown that the size of the rich-club controlling half of the world's trade is actually shrinking. While the gravity law is known to describe well the social interactions in the static networks of population migration, international trade, etc, here for the first time we studied a non-conservative dynamical model based on the gravity law which excellently reproduced many empirical features of the ITN

Structural Changes of International Trade Flows under the Impact of Globalization

Directory of Open Access Journals (Sweden)

Anca Dachin

2006-08-01

Full Text Available Structural changes of international trade flows indicate modifications in competitiveness of countries, in terms of production, technological upgrading and exports under the pressure of globalization. The paper aims to point out sources of competitive advantages especially in manufacturing exports of different groups of countries. The focus is on the shifts in the structure of manufacturing in the European Union and their effects on international rankings in export performances. An important issue refers to the opportunities given by the enlargement of the European Union and their impact on EU trade structures.

Relative Importance of Current and Past Landscape Structure and Local Habitat Conditions for Plant Species Richness in Dry Grassland-Like Forest Openings

Czech Academy of Sciences Publication Activity Database

Husáková, I.; Münzbergová, Zuzana

2014-01-01

Roč. 9, č. 5 (2014), s. 1-15 E-ISSN 1932-6203 Institutional support: RVO:67985939 Keywords : landscape structure * species richness * dry grassland Subject RIV: EF - Botanics Impact factor: 3.234, year: 2014

Rotational characterization of methyl methacrylate: Internal dynamics and structure determination

Science.gov (United States)

Herbers, Sven; Wachsmuth, Dennis; Obenchain, Daniel A.; Grabow, Jens-Uwe

2018-01-01

Rotational constants, Watson's S centrifugal distortion coefficients, and internal rotation parameters of the two most stable conformers of methyl methacrylate were retrieved from the microwave spectrum. Splittings of rotational energy levels were caused by two non equivalent methyl tops. Constraining the centrifugal distortion coefficients and internal rotation parameters to the values of the main isotopologues, the rotational constants of all single substituted 13C and 18O isotopologues were determined. From these rotational constants the substitution structures and semi-empirical zero point structures of both conformers were precisely determined.

PREFACE: International Conference on Structural Nano Composites (NANOSTRUC 2012)

Science.gov (United States)

Njuguna, James

2012-09-01

Dear Colleagues It is a great pleasure to welcome you to NanoStruc2012 at Cranfield University. The purpose of the 2012 International Conference on Structural Nano Composites (NanoStruc2012) is to promote activities in various areas of materials and structures by providing a forum for exchange of ideas, presentation of technical achievements and discussion of future directions. NanoStruc brings together an international community of experts to discuss the state-of-the-art, new research results, perspectives of future developments, and innovative applications relevant to structural materials, engineering structures, nanocomposites, modelling and simulations, and their related application areas. The conference is split in 7 panel sessions, Metallic Nanocomposites and Coatings, Silica based Nanocomposites, safty of Nanomaterials, Carboin based Nanocomposites, Multscale Modelling, Bio materials and Application of Nanomaterials. All accepted Papers will be published in the IOP Conference Series: Materials Science and Engineering (MSE), and included in the NanoStruc online digital library. The abstracts will be indexed in Scopus, Compedex, Inspec, INIS (International Nuclear Information System), Chemical Abstracts, NASA Astrophysics Data System and Polymer Library. Before ending this message, I would like to acknowledge the hard work, professional skills and efficiency of the team which ensured the general organisation. As a conclusion, I would like to Welcome you to the Nanostruc2012 and wish you a stimulating Conference and a wonderful time. On behalf of the scientific committee, Signature James Njuguna Conference Chair The PDF of this preface also contains committee listings and associates logos.

Correlations of External Landmarks With Internal Structures of the Temporal Bone.

Science.gov (United States)

Piromchai, Patorn; Wijewickrema, Sudanthi; Smeds, Henrik; Kennedy, Gregor; O'Leary, Stephen

2015-09-01

The internal anatomy of a temporal bone could be inferred from external landmarks. Mastoid surgery is an important skill that ENT surgeons need to acquire. Surgeons commonly use CT scans as a guide to understanding anatomical variations before surgery. Conversely, in cases where CT scans are not available, or in the temporal bone laboratory where residents are usually not provided with CT scans, it would be beneficial if the internal anatomy of a temporal bone could be inferred from external landmarks. We explored correlations between internal anatomical variations and metrics established to quantify the position of external landmarks that are commonly exposed in the operating room, or the temporal bone laboratory, before commencement of drilling. Mathematical models were developed to predict internal anatomy based on external structures. From an operating room view, the distances between the following external landmarks were observed to have statistically significant correlations with the internal anatomy of a temporal bone: temporal line, external auditory canal, mastoid tip, occipitomastoid suture, and Henle's spine. These structures can be used to infer a low lying dura mater (p = 0.002), an anteriorly located sigmoid sinus (p = 0.006), and a more lateral course of the facial nerve (p external landmarks. The distances between these two landmarks and the operating view external structures were able to further infer the laterality of the facial nerve (p internal structures with a high level of accuracy: the distance from the sigmoid sinus to the posterior external auditory canal (p external landmarks found on the temporal bone. These relationships could be used as a guideline to predict challenges during drilling and choosing appropriate temporal bones for dissection.

Detection, characterization and evolution of internal repeats in Chitinases of known 3-D structure.

Directory of Open Access Journals (Sweden)

Manigandan Sivaji

Full Text Available Chitinase proteins have evolved and diversified almost in all organisms ranging from prokaryotes to eukaryotes. During evolution, internal repeats may appear in amino acid sequences of proteins which alter the structural and functional features. Here we deciphered the internal repeats from Chitinase and characterized the structural similarities between them. Out of 24 diverse Chitinase sequences selected, six sequences (2CJL, 2DSK, 2XVP, 2Z37, 3EBV and 3HBE did not contain any internal repeats of amino acid sequences. Ten sequences contained repeats of length <50, and the remaining 8 sequences contained repeat length between 50 and 100 residues. Two Chitinase sequences, 1ITX and 3SIM, were found to be structurally similar when analyzed using secondary structure of Chitinase from secondary and 3-Dimensional structure database of Protein Data Bank. Internal repeats of 3N17 and 1O6I were also involved in the ligand-binding site of those Chitinase proteins, respectively. Our analyses enhance our understanding towards the identification of structural characteristics of internal repeats in Chitinase proteins.

Bryophyte species richness on retention aspens recovers in time but community structure does not.

Science.gov (United States)

Oldén, Anna; Ovaskainen, Otso; Kotiaho, Janne S; Laaka-Lindberg, Sanna; Halme, Panu

2014-01-01

Green-tree retention is a forest management method in which some living trees are left on a logged area. The aim is to offer 'lifeboats' to support species immediately after logging and to provide microhabitats during and after forest re-establishment. Several studies have shown immediate decline in bryophyte diversity after retention logging and thus questioned the effectiveness of this method, but longer term studies are lacking. Here we studied the epiphytic bryophytes on European aspen (Populus tremula L.) retention trees along a 30-year chronosequence. We compared the bryophyte flora of 102 'retention aspens' on 14 differently aged retention sites with 102 'conservation aspens' on 14 differently aged conservation sites. We used a Bayesian community-level modelling approach to estimate the changes in bryophyte species richness, abundance (area covered) and community structure during 30 years after logging. Using the fitted model, we estimated that two years after logging both species richness and abundance of bryophytes declined, but during the following 20-30 years both recovered to the level of conservation aspens. However, logging-induced changes in bryophyte community structure did not fully recover over the same time period. Liverwort species showed some or low potential to benefit from lifeboating and high potential to re-colonise as time since logging increases. Most moss species responded similarly, but two cushion-forming mosses benefited from the logging disturbance while several weft- or mat-forming mosses declined and did not re-colonise in 20-30 years. We conclude that retention trees do not function as equally effective lifeboats for all bryophyte species but are successful in providing suitable habitats for many species in the long-term. To be most effective, retention cuts should be located adjacent to conservation sites, which may function as sources of re-colonisation and support the populations of species that require old-growth forests.

Bryophyte species richness on retention aspens recovers in time but community structure does not.

Directory of Open Access Journals (Sweden)

Anna Oldén

Full Text Available Green-tree retention is a forest management method in which some living trees are left on a logged area. The aim is to offer 'lifeboats' to support species immediately after logging and to provide microhabitats during and after forest re-establishment. Several studies have shown immediate decline in bryophyte diversity after retention logging and thus questioned the effectiveness of this method, but longer term studies are lacking. Here we studied the epiphytic bryophytes on European aspen (Populus tremula L. retention trees along a 30-year chronosequence. We compared the bryophyte flora of 102 'retention aspens' on 14 differently aged retention sites with 102 'conservation aspens' on 14 differently aged conservation sites. We used a Bayesian community-level modelling approach to estimate the changes in bryophyte species richness, abundance (area covered and community structure during 30 years after logging. Using the fitted model, we estimated that two years after logging both species richness and abundance of bryophytes declined, but during the following 20-30 years both recovered to the level of conservation aspens. However, logging-induced changes in bryophyte community structure did not fully recover over the same time period. Liverwort species showed some or low potential to benefit from lifeboating and high potential to re-colonise as time since logging increases. Most moss species responded similarly, but two cushion-forming mosses benefited from the logging disturbance while several weft- or mat-forming mosses declined and did not re-colonise in 20-30 years. We conclude that retention trees do not function as equally effective lifeboats for all bryophyte species but are successful in providing suitable habitats for many species in the long-term. To be most effective, retention cuts should be located adjacent to conservation sites, which may function as sources of re-colonisation and support the populations of species that require old

Structure-preservingness, internal merge, and the strict locality of triads

NARCIS (Netherlands)

Koster, J.; Karimi, S.; Samiian, V.; Wilkins, W.

2007-01-01

This paper examines Emonds’ Structure Preserving Hypothesis, and suggests that the insight behind this hypothesis survives reformulation in terms of recent minimalist theory: each structure created by internal merge can also, independently, be created by external merge. As before, this makes

Expression, purification and preliminary biochemical and structural characterization of the leucine rich repeat namesake domain of leucine rich repeat kinase 2.

Science.gov (United States)

Vancraenenbroeck, Renée; Lobbestael, Evy; Weeks, Stephen D; Strelkov, Sergei V; Baekelandt, Veerle; Taymans, Jean-Marc; De Maeyer, Marc

2012-03-01

Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of familial Parkinson's disease. Much research effort has been directed towards the catalytic core region of LRRK2 composed of GTPase (ROC, Ras of complex proteins) and kinase domains and a connecting COR (C-terminus of ROC) domain. In contrast, the precise functions of the protein-protein interaction domains, such as the leucine-rich repeat (LRR) domain, are not known. In the present study, we modeled the LRRK2 LRR domain (LRR(LRRK2)) using a template assembly approach, revealing the presence of 14 LRRs. Next, we focused on the expression and purification of LRR(LRRK2) in Escherichia coli. Buffer optimization revealed that the protein requires the presence of a zwitterionic detergent, namely Empigen BB, during solubilization and the subsequent purification and characterization steps. This indicates that the detergent captures the hydrophobic surface patches of LRR(LRRK2) thereby suppressing its aggregation. Circular dichroism (CD) spectroscopy measured 18% α-helices and 21% β-sheets, consistent with predictions from the homology model. Size exclusion chromatography (SEC) and dynamic light scattering measurements showed the presence of a single species, with a Stokes radius corresponding to the model dimensions of a protein monomer. Furthermore, no obvious LRR(LRRK2) multimerization was detected via cross-linking studies. Finally, the LRR(LRRK2) clinical mutations did not influence LRR(LRRK2) secondary, tertiary or quaternary structure as determined via SEC and CD spectroscopy. We therefore conclude that these mutations are likely to affect putative LRR(LRRK2) inter- and intramolecular interactions. Copyright © 2011 Elsevier B.V. All rights reserved.

Structural and Chemical Properties of the Nitrogen-Rich Energetic Material Triaminoguanidinium 1-methyl-5-nitriminotetrazolate under Pressure

Science.gov (United States)

2012-08-01

ABSTRACT 16. SECURITY CLASSIFICATION OF: The structural and chemical properties of the bi-molecular, hydrogen-bonded, nitrogen-rich ener- getic...School Apprenticeship Program (ARO-HSAP), and the Depart- ment of Energy National Nuclear Security Administration (Carnegie/DOE Alliance Center; DE-FC52...B. J. Baer, H. Cynn, W. J. Evans, V. Iota , and C. S. Yoo, Phys. Rev. B 76(1), 014113 (2007). 9T. M. Klapötke, J. Stierstorfer, and A. U. Wallek, Chem

Synthesis, crystal structure investigation and magnetism of the complex metal-rich boride series Crx(Rh1-yRuy)7-xB3 (x=0.88-1; y=0-1) with Th7Fe3-type structure

Science.gov (United States)

Misse, Patrick R. N.; Mbarki, Mohammed; Fokwa, Boniface P. T.

2012-08-01

Powder samples and single crystals of the new complex boride series Crx(Rh1-yRuy)7-xB3 (x=0.88-1; y=0-1) have been synthesized by arc-melting the elements under purified argon atmosphere on a water-cooled copper crucible. The products, which have metallic luster, were structurally characterized by single-crystal and powder X-ray diffraction as well as EDX measurements. Within the whole solid solution range the hexagonal Th7Fe3 structure type (space group P63mc, no. 186, Z=2) was identified. Single-crystal structure refinement results indicate the presence of chromium at two sites (6c and 2b) of the available three metal Wyckoff sites, with a pronounced preference for the 6c site. An unexpected Rh/Ru site preference was found in the Ru-rich region only, leading to two different magnetic behaviors in the solid solution: The Rh-rich region shows a temperature-independent (Pauli) paramagnetism whereas an additional temperature-dependent paramagnetic component is found in the Ru-rich region.

Study on dynamic characteristics of reduced analytical model for PWR reactor internal structures

International Nuclear Information System (INIS)

Yoo, Bong; Lee, Jae Han; Kim, Jong Bum; Koo, Kyeong Hoe

1993-01-01

The objective of this study is to establish the procedure of the reduced analytical modeling technique for the PWR reactor internal(RI) structures and to carry out the sensitivity study of the dynamic characteristics of the structures by varying the structural parameters such as the stiffness, the mass and the damping. Modeling techniques for the PWR reactor internal structures and computer programs used for the dynamic analysis of the reactor internal structures are briefly investigated. Among the many components of RI structures, the dynamic characteristics for CSB was performed. The sensitivity analysis of the dynamic characteristics for the reduced analytical model considering the variations of the stiffnesses for the lower and upper flanges of the CSB and for the RV Snubber were performed to improve the dynamic characteristics of the RI structures against the external loadings given. In order to enhance the structural design margin of the RI components, the nonlinear time history analyses were attempted for the RI reduced models to compare the structural responses between the reference model and the modified one. (Author)

Variation in fish community structure, richness, and diversity in 56 Danish lakes with contrasting depth, size, and trophic state: does the method matter?

DEFF Research Database (Denmark)

Menezes, Rosemberg; Borchsenius, Finn; Svenning, J.-C.

2013-01-01

a better understanding of fish communities. We compare fish community composition, richness, and diversity in 56 Danish lakes using data obtained by gillnetting in different lake zones and near-shore electrofishing, respectively. On average, electrofishing captured more species than offshore gillnets......, but not more than littoral gillnets. Overall, the different fish sampling methods showed consistency as to fish community structure, but noticeable differences in community–environment relationships. Lake area was the best predictor for fish species richness in the littoral samplings, while it was poor...... community, as all methods miss some important species that other methods capture. However, electrofishing seems to be a fast alternative to gillnets for monitoring fish species richness and composition in littoral habitats of Danish lakes....

Procedures of ASME code case N-201 for KALIMER. Reactor internal structures

International Nuclear Information System (INIS)

Koo, Gyeong Hoi; Yoo, B.

2001-02-01

The main objective of this report is to describe the design procedure of ASME Boiler and Pressure Vessel Code, Code Case N-201-4, which is an elevated temperature structural design code of the Nuclear reactor internal structures, checking the criteria of stress limit, accumulated inelastic strain and deformation, creep-fatigue damage, and buckling limit. As one of examples, the creep-fatigue damage evaluations are carried out for the KALIMER reactor internal structures of baffle annulus. This report is expected to be very useful in evaluating the structural integrity of the liquid metal reactor operating under an elevated temperature

Nano-phase separation and structural ordering in silica-rich mixed network former glasses.

Science.gov (United States)

Liu, Hao; Youngman, Randall E; Kapoor, Saurabh; Jensen, Lars R; Smedskjaer, Morten M; Yue, Yuanzheng

2018-06-13

We investigate the structure, phase separation, glass transition, and crystallization in a mixed network former glass series, i.e., B2O3-Al2O3-SiO2-P2O5 glasses with varying SiO2/B2O3 molar ratio. All the studied glasses exhibit two separate glassy phases: droplet phase (G1) with the size of 50-100 nm and matrix phase (G2), corresponding to a lower calorimetric glass transition temperature (Tg1) and a higher one (Tg2), respectively. Both Tg values decrease linearly with the substitution of B2O3 for SiO2, but the magnitude of the decrease is larger for Tg1. Based on nuclear magnetic resonance and Raman spectroscopy results, we infer that the G1 phase is rich in boroxol rings, while the G2 phase mainly involves the B-O-Si network. Both phases contain BPO4- and AlPO4-like units. Ordered domains occur in G2 upon isothermal and dynamic heating, driven by the structural heterogeneity in the as-prepared glasses. The structural ordering lowers the activation energy of crystal growth, thus promoting partial crystallization of G2. These findings are useful for understanding glass formation and phase separation in mixed network former oxide systems, and for tailoring their properties.

Proceedings of 18th international conference on structural mechanics in reactor technology

International Nuclear Information System (INIS)

2005-07-01

The 18th International Conference on Structural Mechanics in Reactor Technology was held on August 7-12, 2005 in Beijing, China, and Sponsored by International Association for Structural Mechanics in Reactor Technology, Chinese Nuclear Society, Chinese Society of Theoretical and Applied Mechanics, and Tsinghua University. 486 abstracts are Collected. The contents includes: opening, plenary and keynote presentations; computational mechanics; fuel and core structures; aging, life extension, and license renewal; design methods and rules for components; fracture mechanics; concrete material, containment and other structures; analysis and design for dynamic and extreme loads; seismic analysis, design and qualification; structural reliability and probabilistic safety assessment (PSA); operation, inspection and maintenance; severe accident management and structural evaluation; advanced reactors and generation IV reactors; decommissioning of nuclear facilities and waste management.

Desipramine induces disorder in cholesterol-rich membranes: implications for viral trafficking

Science.gov (United States)

Pakkanen, Kirsi; Salonen, Emppu; Mäkelä, Anna R.; Oker-Blom, Christian; Vattulainen, Ilpo; Vuento, Matti

2009-12-01

In this study, the effect of desipramine (DMI) on phospholipid bilayers and parvoviral entry was elucidated. In atomistic molecular dynamics simulations, DMI was found to introduce disorder in cholesterol-rich phospholipid bilayers. This was manifested by a decrease in the deuterium order parameter SCD as well as an increase in the membrane area. Disordering of the membrane suggested DMI to destabilize cholesterol-rich membrane domains (rafts) in cellular conditions. To relate the raft disrupting ability of DMI with novel biological relevance, we studied the intracellular effect of DMI using canine parvovirus (CPV), a virus known to interact with endosomal membranes and sphingomyelin, as an intracellular probe. DMI was found to cause retention of the virus in intracellular vesicular structures leading to the inhibition of viral proliferation. This implies that DMI has a deleterious effect on the viral traffic. As recycling endosomes and the internal vesicles of multivesicular bodies are known to contain raft components, the effect of desipramine beyond the plasma membrane step could be caused by raft disruption leading to impaired endosomal function and possibly have direct influence on the penetration of the virus through an endosomal membrane.

Desipramine induces disorder in cholesterol-rich membranes: implications for viral trafficking

International Nuclear Information System (INIS)

Pakkanen, Kirsi; Mäkelä, Anna R; Oker-Blom, Christian; Vuento, Matti; Salonen, Emppu; Vattulainen, Ilpo

2009-01-01

In this study, the effect of desipramine (DMI) on phospholipid bilayers and parvoviral entry was elucidated. In atomistic molecular dynamics simulations, DMI was found to introduce disorder in cholesterol-rich phospholipid bilayers. This was manifested by a decrease in the deuterium order parameter S CD as well as an increase in the membrane area. Disordering of the membrane suggested DMI to destabilize cholesterol-rich membrane domains (rafts) in cellular conditions. To relate the raft disrupting ability of DMI with novel biological relevance, we studied the intracellular effect of DMI using canine parvovirus (CPV), a virus known to interact with endosomal membranes and sphingomyelin, as an intracellular probe. DMI was found to cause retention of the virus in intracellular vesicular structures leading to the inhibition of viral proliferation. This implies that DMI has a deleterious effect on the viral traffic. As recycling endosomes and the internal vesicles of multivesicular bodies are known to contain raft components, the effect of desipramine beyond the plasma membrane step could be caused by raft disruption leading to impaired endosomal function and possibly have direct influence on the penetration of the virus through an endosomal membrane

International seminar on structural investigations on pulsed neutron sources. Proceedings

International Nuclear Information System (INIS)

Aksenov, V.L.; Balagurov, A.M.; Taran, Yu.V.

1993-01-01

The proceedings of the International seminar on structural investigations using pulsed neutron sources are presented. The seminar is dedicated to the memory of Dr. Yu.M. Ostanevich, a world acknowledged physicist. The problems of structural analysis using pulsed neutron source at the IBR-2 reactor are discussed

Nanofat-derived stem cells with platelet-rich fibrin improve facial contour remodeling and skin rejuvenation after autologous structural fat transplantation

Science.gov (United States)

Liang, Zhi-Jie; Chen, Hai; Zhu, Mao-Guang; Xu, Fang-Tian; He, Ning; Wei, Xiao-Juan; Li, Hong-Mian

2017-01-01

Traditional autologous fat transplantation is a common surgical procedure for treating facial soft tissue depression and skin aging. However, the transplanted fat is easily absorbed, reducing the long-term efficacy of the procedure. Here, we examined the efficacy of nanofat-assisted autologous fat structural transplantation. Nanofat-derived stem cells (NFSCs) were isolated, mechanically emulsified, cultured, and characterized. Platelet-rich fibrin (PRF) enhanced proliferation and adipogenic differentiation of NFSCs in vitro. We then compared 62 test group patients with soft tissue depression or signs of aging who underwent combined nanofat, PRF, and autologous fat structural transplantation to control patients (77 cases) who underwent traditional autologous fat transplantation. Facial soft tissue depression symptoms and skin texture were improved to a greater extent after nanofat transplants than after traditional transplants, and the nanofat group had an overall satisfaction rate above 90%. These data suggest that NFSCs function similarly to mesenchymal stem cells and share many of the biological characteristics of traditional fat stem cell cultures. Transplants that combine newly-isolated nanofat, which has a rich stromal vascular fraction (SVF), with PRF and autologous structural fat granules may therefore be a safe, highly-effective, and long-lasting method for remodeling facial contours and rejuvenating the skin. PMID:28978136

[Volunteer satisfaction: Internal structure and relationship with permanence in organizations].

Science.gov (United States)

Vecina Jiménez, M L; Chacón Fuertes, Fernando; Sueiro Abad, Manuel J

2009-02-01

Volunteer satisfaction: Internal structure and relationship with permanence in organizations. The concept of satisfaction is considered theoretically relevant in practically all the studies that have investigated the factors that influence the permanence of volunteer participation in organizations. However, the practical results are not conclusive, perhaps due to the wide range of ways in which the concept is understood and measured. The object of this study is: to analyse the internal structure of satisfaction and to verify its relationship with volunteer duration in organizations. The results of the factor analysis yield a three-factor structure: Satisfaction with the management of the organization, Satisfaction with the tasks, Satisfaction of motivations. The three factors allow us to differentiate between individuals who remain in the organization for a period of 12 consecutive months, and those who leave earlier. The results of structural equation model analysis show that the relationship between satisfaction and the length of time that volunteers stay with the organization is affected by the intention to remain.

Studies on muon tomography for archaeological internal structures scanning

Science.gov (United States)

Gómez, H.; Carloganu, C.; Gibert, D.; Jacquemier, J.; Karyotakis, Y.; Marteau, J.; Niess, V.; Katsanevas, S.; Tonazzo, A.

2016-05-01

Muon tomography is a potential non-invasive technique for internal structure scanning. It has already interesting applications in geophysics and can be used for archaeological purposes. Muon tomography is based on the measurement of the muon flux after crossing the structure studied. Differences on the mean density of these structures imply differences on the detected muon rate for a given direction. Based on this principle, Monte Carlo simulations represent a useful tool to provide a model of the expected muon rate and angular distribution depending on the composition of the studied object, being useful to estimate the expected detected muons and to better understand the experimental results. These simulations are mainly dependent on the geometry and composition of the studied object and on the modelling of the initial muon flux at surface. In this work, the potential of muon tomography in archaeology is presented and evaluated with Monte Carlo simulations by estimating the differences on the muon rate due to the presence of internal structures and its composition. The influence of the chosen muon model at surface in terms of energy and angular distributions in the final result has been also studied.

Structural-phenomenological features of the internal picture of doctors’ illnesses

Directory of Open Access Journals (Sweden)

Lazarenko, Victor A.

2016-06-01

Full Text Available The vocational activities of doctors and their social status do not ensure their health. And, falling ill, doctors don’t identify themselves with ordinary patients as they have a deep knowledge of medicine. Thus, the internal picture of a doctor’s illness is both a research and a practical problem: the problem of the psychoprevention of doctors’ illnesses at all stages of their professionalization. The purpose of the research was to study the phenomenological features of the internal picture of doctors’ illnesses using the structural approach. The total number of participants was 132. The experimental group consisted of 66 sick doctors, differentiated according to their stage of professionalization: vocational training (students, professional adaptation (interns, full professionalization (doctors. The control group consisted of 66 people who did not have any medical education. All the control subjects were hospitalized with chronic diseases during the study period. The organization of the research was carried out with the use of clinical-psychological and diagnostic methods, the methods of descriptive statistics, and comparative, multidimensional, and structural analysis. The research revealed the following phenomenological features of the internal picture of doctors’ illnesses: the prevalence of some anxiety in the doctors and high awareness of their health; the doctors’ altruistic orientation; their willingness to work despite difficulties; and their ability to achieve high results in different activities. The structural features of the doctors’ image of their own diseases on the cognitive level were the following: qualitative heterogeneity during in-service activities; a high degree of image integration during in-service activities; and stereotyped perceptions of the disease. The emotional level revealed the emotional distance between doctors and their patients, and the behavioral level revealed doctors’ disregard for the

Future Mars geophysical observatories for understanding its internal structure, rotation, and evolution

Science.gov (United States)

Dehant, Veronique; Banerdt, Bruce; Lognonné, Philippe; Grott, Matthias; Asmar, Sami; Biele, Jens; Breuer, Doris; Forget, François; Jaumann, Ralf; Johnson, Catherine; Knapmeyer, Martin; Langlais, Benoit; Le Feuvre, Mathieu; Mimoun, David; Mocquet, Antoine; Read, Peter; Rivoldini, Attilio; Romberg, Oliver; Schubert, Gerald; Smrekar, Sue; Spohn, Tilman; Tortora, Paolo; Ulamec, Stephan; Vennerstrøm, Susanne

2012-08-01

Our fundamental understanding of the interior of the Earth comes from seismology, geodesy, geochemistry, geomagnetism, geothermal studies, and petrology. For the Earth, measurements in those disciplines of geophysics have revealed the basic internal layering of the Earth, its dynamical regime, its thermal structure, its gross compositional stratification, as well as significant lateral variations in these quantities. Planetary interiors not only record evidence of conditions of planetary accretion and differentiation, they exert significant control on surface environments. We present recent advances in possible in-situ investigations of the interior of Mars, experiments and strategies that can provide unique and critical information about the fundamental processes of terrestrial planet formation and evolution. Such investigations applied on Mars have been ranked as a high priority in virtually every set of European, US and international high-level planetary science recommendations for the past 30 years. New seismological methods and approaches based on the cross-correlation of seismic noise by two seismic stations/landers on the surface of Mars and on joint seismic/orbiter detection of meteorite impacts, as well as the improvement of the performance of Very Broad-Band (VBB) seismometers have made it possible to secure a rich scientific return with only two simultaneously recording stations. In parallel, use of interferometric methods based on two Earth-Mars radio links simultaneously from landers tracked from Earth has increased the precision of radio science experiments by one order of magnitude. Magnetometer and heat flow measurements will complement seismic and geodetic data in order to obtain the best information on the interior of Mars. In addition to studying the present structure and dynamics of Mars, these measurements will provide important constraints for the astrobiology of Mars by helping to understand why Mars failed to sustain a magnetic field, by

Maxwell-Higgs vortices with internal structure

Science.gov (United States)

Bazeia, D.; Marques, M. A.; Menezes, R.

2018-05-01

Vortices are considered in relativistic Maxwell-Higgs systems in interaction with a neutral scalar field. The gauge field interacts with the neutral field via the presence of generalized permeability, and the charged and neutral scalar fields interact in a way dictated by the presence of first order differential equations that solve the equations of motion. The neutral field may be seen as the source field of the vortex, and we study some possibilities, which modify the standard Maxwell-Higgs solution and include internal structure to the vortex.

Effects of internal structure on equilibrium of field-reversed configuration plasma sustained by rotating magnetic field

International Nuclear Information System (INIS)

Yambe, Kiyoyuki; Inomoto, Michiaki; Okada, Shigefumi; Kobayashi, Yuka; Asai, Tomohiko

2008-01-01

The effects of an internal structure on the equilibrium of a field-reversed configuration (FRC) plasma sustained by rotating magnetic field is investigated by using detailed electrostatic probe measurements in the FRC Injection Experiment apparatus [S. Okada, et al., Nucl. Fusion. 45, 1094 (2005)]. An internal structure installed axially on the geometrical axis, which simulates Ohmic transformer or external toroidal field coils on the FRC device, brings about substantial changes in plasma density profile. The internal structure generates steep density-gradients not only on the inner side but on the outer side of the torus. The radial electric field is observed to sustain the ion thermal pressure-gradient in the FRC without the internal structure; however, the radial electric field is not sufficient to sustain the increased ion thermal pressure-gradient in the FRC with the internal structure. Spontaneously driven azimuthal ion flow will be accountable for the imbalance of the radial pressure which is modified by the internal structure.

Origin of the latitudinal richness gradient

DEFF Research Database (Denmark)

Engemann, Kristine; Sandel, Brody Steven; Enquist, Brian J.

2015-01-01

Spatial variation in richness patterns must be due to variation in rates of speciation, extinction, immigration and emigration. Hotspots of diversity can occur either because they are hotspots of speciation (cradles) or cold spots of extinction (museums) – two major hypotheses that make contrasting...... predictions for the phylogenetic structure of communities. We test these hypotheses by comparing centers of species richness and phylogenetic clustering for vascular plants in the New World. Range maps for 88,417 plant species were extracted from the Botanical Information and Ecology Network (BIEN) database...... and combined with the BIEN mega phylogeny of >80,000 species. We calculated the Phylogenetic Diversity Index (PDI) and Net Relatedness Index (NRI) for each cell in a 100×100 km grid using a new computationally efficient algorithm. Species richness patterns were compared to patterns of PDI and NRI. We found...

Evaluating Lignin-Rich Residues from Biochemical Ethanol Production of Wheat Straw and Olive Tree Pruning by FTIR and 2D-NMR

Directory of Open Access Journals (Sweden)

José I. Santos

2015-01-01

Full Text Available Lignin-rich residues from the cellulose-based industry are traditionally incinerated for internal energy use. The future biorefineries that convert cellulosic biomass into biofuels will generate more lignin than necessary for internal energy use, and therefore value-added products from lignin could be produced. In this context, a good understanding of lignin is necessary prior to its valorization. The present study focused on the characterization of lignin-rich residues from biochemical ethanol production, including steam explosion, saccharification, and fermentation, of wheat straw and olive tree pruning. In addition to the composition and purity, the lignin structures (S/G ratio, interunit linkages were investigated by spectroscopy techniques such as FTIR and 2D-NMR. Together with the high lignin content, both residues contained significant amounts of carbohydrates, mainly glucose and protein. Wheat straw lignin showed a very low S/G ratio associated with p-hydroxycinnamates (p-coumarate and ferulate, whereas a strong predominance of S over G units was observed for olive tree pruning lignin. The main interunit linkages present in both lignins were β-O-4′ ethers followed by resinols and phenylcoumarans. These structural characteristics determine the use of these lignins in respect to their valorization.

Vacancy enhanced formation and phase transition of Cu-rich precipitates in α - iron under neutron irradiation

Energy Technology Data Exchange (ETDEWEB)

Lv, G. C. [Basic Experimental Center of Natural Science, University of Science and Technology Beijing, Beijing, 100083 (China); Corrosion and Protection Center, Key Laboratory of Environmental Fracture (MOE), University of Science and Technology Beijing, Beijing, 100083 (China); Zhang, H. [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Canada, T6G2V4 (Canada); He, X. F.; Yang, W. [China Institute of Atomic Energy, Beijing, 102413 (China); Su, Y. J., E-mail: yjsu@ustb.edu.cn [Corrosion and Protection Center, Key Laboratory of Environmental Fracture (MOE), University of Science and Technology Beijing, Beijing, 100083 (China)

2016-04-15

In this paper, we employed both molecular statics and molecular dynamics simulation methods to investigate the role of vacancies in the formation and phase transition of Cu-rich precipitates in α-iron. The results indicated that vacancies promoted the diffusion of Cu atoms to form Cu-rich precipitates. After Cu-rich precipitates formed, they further trapped vacancies. The supersaturated vacancy concentration in the Cu-rich precipitate induced a shear strain, which triggered the phase transition from bcc to fcc structure by transforming the initial bcc (110) plane into fcc (111) plane. In addition, the formation of the fcc-twin structure and the stacking fault structure in the Cu-rich precipitates was observed in dynamics simulations.

Structure and function of ABCG2-rich extracellular vesicles mediating multidrug resistance.

Directory of Open Access Journals (Sweden)

Vicky Goler-Baron

2011-01-01

Full Text Available Multidrug resistance (MDR is a major impediment to curative cancer chemotherapy. The ATP-Binding Cassette transporters ABCG2, ABCB1 and ABCC2 form a unique defense network against multiple structurally and functionally distinct chemotherapeutics, thereby resulting in MDR. Thus, deciphering novel mechanisms of MDR and their overcoming is a major goal of cancer research. Recently we have shown that overexpression of ABCG2 in the membrane of novel extracellular vesicles (EVs in breast cancer cells results in mitoxantrone resistance due to its dramatic sequestration in EVs. However, nothing is known about EVs structure, biogenesis and their ability to concentrate multiple antitumor agents. To this end, we here found that EVs are structural and functional homologues of bile canaliculi, are apically localized, sealed structures reinforced by an actin-based cytoskeleton and secluded from the extracellular milieu by the tight junction proteins occludin and ZO-1. Apart from ABCG2, ABCB1 and ABCC2 were also selectively targeted to the membrane of EVs. Moreover, Ezrin-Radixin-Moesin protein complex selectively localized to the border of the EVs membrane, suggesting a key role for the tethering of MDR pumps to the actin cytoskeleton. The ability of EVs to concentrate and sequester different antitumor drugs was also explored. Taking advantage of the endogenous fluorescence of anticancer drugs, we found that EVs-forming breast cancer cells display high level resistance to topotecan, imidazoacridinones and methotrexate via efficient intravesicular drug concentration hence sequestering them away from their cellular targets. Thus, we identified a new modality of anticancer drug compartmentalization and resistance in which multiple chemotherapeutics are actively pumped from the cytoplasm and highly concentrated within the lumen of EVs via a network of MDR transporters differentially targeted to the EVs membrane. We propose a composite model for the structure and

Ocean-Continent Transition Structure of the Pelotas Magma-Rich Continental Margin, South Atlantic

Science.gov (United States)

Harkin, Caroline; Kusznir, Nick; Roberts, Alan; Manatschal, Gianreto; McDermott, Ken

2017-04-01

Rifted continental margins in the southern South Atlantic are magma-rich showing well developed volcanic extrusives known as seaward dipping reflectors (SDRs). Here we examine the magma-rich continental rifted margin of the Pelotas Basin, offshore Brazil. Deep seismic reflection data displays a large package of seaward dipping reflectors with an approximate width of 200 km and a varying thickness of 10 km to 17 km that have previously been interpreted as volcanic SDRs. We examine these SDRs to explore if they are composed predominantly of basaltic or sedimentary-volcaniclastic material. We also study the thickness of the crustal basement beneath the SDRs. Additionally we investigate if these SDRs are underlain by thin 'hyper-extended' continental crust or if they have been deposited on new magmatic basement. The answers to these questions are important in understanding the structure and formation processes of magma-rich continental margins. We use gravity inversion to investigate SDR composition by varying the proportion of basalt to sediments-volcaniclastics (basalt fraction) which determines the SDR densities in the gravity inversion. By matching the Moho depth and two-way travel time from gravity inversion and deep seismic reflection data, we determine the lateral variation in basalt fraction of the SDRs. Our analysis suggests: 1) There is an overall pattern of SDR basalt fraction and bulk density decreasing oceanward. This could be due to increasing sediment content oceanward or it could result from the change in basalt flows to hyaloclastites as water depth increases. 2) The SDR package can be split into two distinct sub packages based on the basalt fraction results, where the proximal side of each package has a higher basalt fraction and density. 3) The inner SDR package contains reflectors that bear a resemblance to the SDRs described by Hinz (1981) corresponding to syn-tectonic volcanic eruptions into an extensional basin, while the outer SDR package has

Design of complex bone internal structure using topology optimization with perimeter control.

Science.gov (United States)

Park, Jaejong; Sutradhar, Alok; Shah, Jami J; Paulino, Glaucio H

2018-03-01

Large facial bone loss usually requires patient-specific bone implants to restore the structural integrity and functionality that also affects the appearance of each patient. Titanium alloys (e.g., Ti-6Al-4V) are typically used in the interfacial porous coatings between the implant and the surrounding bone to promote stability. There exists a property mismatch between the two that in general leads to complications such as stress-shielding. This biomechanical discrepancy is a hurdle in the design of bone replacements. To alleviate the mismatch, the internal structure of the bone replacements should match that of the bone. Topology optimization has proven to be a good technique for designing bone replacements. However, the complex internal structure of the bone is difficult to mimic using conventional topology optimization methods without additional restrictions. In this work, the complex bone internal structure is recovered using a perimeter control based topology optimization approach. By restricting the solution space by means of the perimeter, the intricate design complexity of bones can be achieved. Three different bone regions with well-known physiological loadings are selected to illustrate the method. Additionally, we found that the target perimeter value and the pattern of the initial distribution play a vital role in obtaining the natural curvatures in the bone internal structures as well as avoiding excessive island patterns. Copyright © 2018 Elsevier Ltd. All rights reserved.

Synthesis, electronic structure, elastic properties, and interfacial behavior of icosahedral boron-rich solids

Energy Technology Data Exchange (ETDEWEB)

Hunold, Oliver

2017-08-01

Boron-rich solids are commonly characterized by icosahedral clusters, where 12 B atoms form an icosahedron, giving rise to outstanding mechanical and transport properties. However, broader applications are limited due to the high synthesis temperature required to obtain the icosahedra-based crystalline structure. Utilizing high power pulsed magnetron sputtering (HPPMS), the deposition temperature may be lowered as compared to direct current magnetron sputtering by enhanced surface diffusion. Therefore, HPPMS was utilized to investigate the influence of the substrate temperature on the structural evolution of B-rich Al-Y-B thin films. The formation of the intended AlYB{sub 14} phase together with the (Y,Al)B{sub 6} impurity phase, containing 1.8 at.% less B than AlYB{sub 14}, was observed at a growth temperature of 800 C and hence 600 C below the bulk synthesis temperature. Based on density functional theory (DFT) calculations it is inferred that minute compositional variations may lead to formation of competing phases, such as (Y,Al)B{sub 6}. Furthermore, 800 C still limits the usage significantly. Therefore, quantum mechanical material design was applied to identify phases with even higher phase stabilities compared to AlYB{sub 14}. Phase stability of T{sub 0.75}Y{sub 0.75}B{sub 14} (T= Sc, Ti, V, Y, Zr, Nb, Si) critically depends on the exact magnitude of charge transferred by T and Y to the B icosahedra. The highest phase stabilities have been identified for Sc{sub 0.75}Y{sub 0.75}B{sub 14}, Ti{sub 0.75}Y{sub 0.75}B{sub 14}, and Zr{sub 0.75}Y{sub 0.75}B{sub 14}. ln combination with Young's modulus values up to 517 GPa these phases are very interesting from a wear-resistance point of view. Still high synthesis temperatures limit the use of such systems onto technologically relevant substrate materials. However, amorphous B-rich solids, which can be synthesized without additional heating, exhibit attractive mechanical and electrical properties. Within these

THE REACH AND RICHNESS OF WIKINOMICS: IS THE FREE WEB-BASED ENCYCLOPEDIA WIKIPEDIA ONLY FOR RICH COUNTRIES?

DEFF Research Database (Denmark)

Rask, Morten

2007-01-01

In this article, a model of the patterns of correlation in Wikipedia, reach and richness, lays the foundation for studying whether the free Web-based encyclopedia Wikipedia is only for developed countries. Based on data from 12 different Wikipedia language editions, the author finds that the cent......In this article, a model of the patterns of correlation in Wikipedia, reach and richness, lays the foundation for studying whether the free Web-based encyclopedia Wikipedia is only for developed countries. Based on data from 12 different Wikipedia language editions, the author finds...... that the central structural effect is on the level of human development in the current country. In other words, Wikipedia is in general more for rich countries than for less developed countries. It is suggested that policy makers make investments in increasing the general level of literacy, education, and standard...

Elite International Schools in the Global South: Transnational Space, Class Relationalities and the "Middling" International Schoolteacher

Science.gov (United States)

Tarc, Paul; Mishra Tarc, Aparna

2015-01-01

The elite international school is a rich site for sociological inquiry in global times. In this paper, we conceptualize the international school as a transnational space of agonist social class-making given the dynamic positioning of the complement of international school actors. We position international schoolteachers in the middle of these…

Structural analysis of the Upper Internals Structure for the Clinch River Breeder Reactor Plant

International Nuclear Information System (INIS)

Houtman, J.L.

1979-01-01

The Upper Internals Structure (UIS) of the Clinch River Breeder Reactor Plant (CRBRP) provides control of core outlet flow to prevent severe thermal transients from occuring at the reactor vessel and primary heat transport outlet piping, provides instrumentation to monitor core performance, provides support for the control rod drivelines, and provides secondary holddown of the core. All of the structural analysis aspects of assuring the UIS is structurally adequate are presented including simplified and rigorous inelastic analysis methods, elevated temperature criteria, environmental effects on material properties, design techniques, and manufacturing constraints

Detection of internal structure by scattered light intensity: Application to kidney cell sorting

Science.gov (United States)

Goolsby, C. L.; Kunze, M. E.

1985-01-01

Scattered light measurements in flow cytometry were sucessfully used to distinguish cells on the basis of differing morphology and internal structure. Differences in scattered light patterns due to changes in internal structure would be expected to occur at large scattering angles. Practically, the results of these calculations suggest that in experimental situations an array of detectors would be useful. Although in general the detection of the scattered light intensity at several intervals within the 10 to 60 region would be sufficient, there are many examples where increased sensitivity could be acheived at other angles. The ability to measure at many different angular intervals would allow the experimenter to empirically select the optimum intervals for the varying conditions of cell size, N/C ratio, granule size and internal structure from sample to sample. The feasibility of making scattered light measurements at many different intervals in flow cytometry was demonstrated. The implementation of simplified versions of these techniques in conjunction with independant measurements of cell size could potentially improve the usefulness of flow cytometry in the study of the internal structure of cells.

Structural reasons for vertical integration in the international oil industry

International Nuclear Information System (INIS)

Luciani, G.

1991-01-01

Once upon a time, the international oil industry was vertically integrated. A small group of companies controlled a very substantial share of international oil flows, extending their operations from the oil well to the gas pump, and relying on intracorporate transfers for most in-between transactions. The historical reasons for vertical disintegration, the market role, and structural reasons for vertical reintegration are examined. (author)

Vibration monitoring of the mechanical behavior of the internal structures of PWR reactors

International Nuclear Information System (INIS)

Assedo, R.; Carre, J.C.; Sol, J.C.

1979-01-01

The internal structures of pressurized water reactors are the seat of vibrations induced by fluctuations in primary fluid flow. A knowledge of these phenomena is indispensable in order to ensure that the structures are in proper mechanical order. It can also be used for operational monitoring. This paper describes all the methods developed and the results already achieved in this domain. The first part deals with tests on mockup associated with the calculation models which afforded a good knowledge of the vibrational characteristics of the internal structures, as well as the measurements made during hot tests of certain reactors which made it possible to qualify these models on real structures. The second part describes the means of detection (neutron noise, external accelerometers) as well as the processing methods used in the follow-up. A few typical results obtained on site are then presented. Finally, the general principles of operational monitoring of the mechanical behavior of the internal structures are described [fr

Studies in stellar evolution. 3. The internal structure constants

International Nuclear Information System (INIS)

Hejlesen, P.M.

1987-01-01

This is the third paper in a series describing the results of extensive stellar evolution calculations. The internal structure constants k j (j = 2, 3, 4) have been computed for a fine grid of stellar models covering the HR-diagram from the zero-age main sequence to the subgiant region. These constants represent the influence of the internal structure on the disturbing potentials of stars, and they are needed for prediction of theoretical apsidal motion rates in close eccentric binaries as well as for other tidal effects. Results for four different initial chemical compositions are presented. The opacity tables by Cox and Stewart (1969) have been adopted, and a mixing length parameter of l/H p = 2.0 has been used throughout. The results are compared with previous calculations. A comparison with observational data for eclipsing binaries will be published elsewhere

Students' Knowledge about the Internal Structure of Mice and Cockroaches in Their Environment

Science.gov (United States)

Kilic, Selda

2013-01-01

The aim of this study is to determine 9th class students knowledge about the internal structures of mice and cockroaches using drawings. Drawings of 122 students from the 9th class of a high school in the center of Konya about the internal structures of mice and cockroaches have been analyzed. Drawings were analyzed independently by two…

3D confocal Raman imaging of oil-rich emulsion from enzyme-assisted aqueous extraction of extruded soybean powder.

Science.gov (United States)

Wu, Longkun; Wang, Limin; Qi, Baokun; Zhang, Xiaonan; Chen, Fusheng; Li, Yang; Sui, Xiaonan; Jiang, Lianzhou

2018-05-30

The understanding of the structure morphology of oil-rich emulsion from enzyme-assisted extraction processing (EAEP) was a critical step to break the oil-rich emulsion structure in order to recover oil. Albeit EAEP method has been applied as an alternative way to conventional solvent extraction method, the structure morphology of oil-rich emulsion was still unclear. The current study aimed to investigate the structure morphology of oil-rich emulsion from EAEP using 3D confocal Raman imaging technique. With increasing the enzymatic hydrolysis duration from 1 to 3 h, the stability of oil-rich emulsion was decreased as visualized in the 3D confocal Raman images that the protein and oil were mixed together. The subsequent Raman spectrum analysis further revealed that the decreased stability of oil-rich emulsion was due to the protein aggregations via SS bonds or protein-lipid interactions. The conformational transfer in protein indicated the formation of a compact structure. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental study of the structure of rich premixed 1,3-butadiene/CH4/O2/Ar flame

OpenAIRE

Gueniche, Hadj-Ali; Glaude, Pierre-Alexandre; Fournet, René; Battin-Leclerc, Frédérique

2007-01-01

The structure of a laminar rich premixed 1,3-C4H6/CH4/O2/Ar flame have been investigated. 1,3-Butadiene, methane, oxygen and argon mole fractions are 0.033; 0.2073; 0.3315, and 0.4280, respectively, for an equivalent ratio of 1.80. The flame has been stabilized on a burner at a pressure of 6.7 kPa (50 Torr). The concentration profiles of stable species were measured by gas chromatography after sampling with a quartz probe. Quantified species included carbon monoxide and dioxide, methane, oxyg...

Hyperfine structure and isotope shift of the neutron-rich barium isotopes 139-146Ba and 148Ba

International Nuclear Information System (INIS)

Wendt, K.; Ahmad, S.A.; Klempt, W.; Neugart, R.; Otten, E.W.

1988-01-01

The hyperfine structure and isotope shift in the 6s 2 S 1/2 -6p 2 P 3/2 line of Ba II (455.4 nm) have been measured by collinear fast-beam laser spectroscopy for the neutron-rich isotopes 139-146 Ba and 148 Ba. Nuclear moments and mean square charge radii of these isotopes have been recalculated. The isotope shift of the isotope 148 Ba (T 1/2 = 0.64 s) could be studied for the first time, yielding δ 2 > 138,148 = 1.245(3) fm 2 . (orig.)

Characterization of the cell penetrating properties of a human salivary proline-rich peptide.

Science.gov (United States)

Radicioni, Giorgia; Stringaro, Annarita; Molinari, Agnese; Nocca, Giuseppina; Longhi, Renato; Pirolli, Davide; Scarano, Emanuele; Iavarone, Federica; Manconi, Barbara; Cabras, Tiziana; Messana, Irene; Castagnola, Massimo; Vitali, Alberto

2015-11-01

Saliva contains hundreds of small proline-rich peptides most of which derive from the post-translational and post-secretory processing of the acidic and basic salivary proline-rich proteins. Among these peptides we found that a 20 residue proline-rich peptide (p1932), commonly present in human saliva and patented for its antiviral activity, was internalized within cells of the oral mucosa. The cell-penetrating properties of p1932 have been studied in a primary gingival fibroblast cell line and in a squamous cancer cell line, and compared to its retro-inverso form. We observed by mass-spectrometry, flow cytometry and confocal microscopy that both peptides were internalized in the two cell lines on a time scale of minutes, being the natural form more efficient than the retro-inverso one. The cytosolic localization was dependent on the cell type: both peptide forms were able to localize within nuclei of tumoral cells, but not in the nuclei of gingival fibroblasts. The uptake was shown to be dependent on the culture conditions used: peptide internalization was indeed effective in a complete medium than in a serum-free one allowing the hypothesis that the internalization could be dependent on the cell cycle. Both peptides were internalized likely by a lipid raft-mediated endocytosis mechanism as suggested by the reduced uptake in the presence of methyl-ß-cyclodextrin. These results suggest that the natural peptide may play a role within the cells of the oral mucosa after its secretion and subsequent internalization. Furthermore, lack of cytotoxicity of both peptide forms highlights their possible application as novel drug delivery agents.

Slurry dispersion state as a parameter to control internal structure of alumina green compact

Energy Technology Data Exchange (ETDEWEB)

Saito, M.; Shui, A.; Tanaka, S.; Uchida, N.; Uematsu, K. [Nagaoka Univ. of Technology, Niigata (Japan)

2002-07-01

The dispersion state of slurry must be controlled to produce granules with appropriated properties for pressing. In this study dispersion state of alumina slurry is changed to form granules with different morphology, deformation property and packing density, and the influence on the internal structure of green compact are presented. Novel methods applying liquid immersion technique coupled with different type of microscopy were used to characterize the internal structures of green compacts. Two types of granules were obtained: dimpled, hard and dense granule, and spherical, soft and loose granule. The respective internal structures of green compacts were totally different. (orig.)

Internal structure changes of eyelash induced by eye makeup.

Science.gov (United States)

Fukami, Ken-Ichi; Inoue, Takafumi; Kawai, Tomomitsu; Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio

2014-01-01

To investigate how eye makeup affects eyelash structure, internal structure of eyelashes were observed with a scanning X-ray microscopic tomography system using synchrotron radiation light source. Eyelash samples were obtained from 36 Japanese women aged 20-70 years and whose use of eye makeup differed. Reconstructed cross-sectional images showed that the structure of the eyelash closely resembled that of scalp hair. The eyelash structure is changed by use of eye makeup. There was a positive correlation between the frequency of mascara use and the degree of cracking in cuticle. The positive correlation was also found between the frequency of mascara use and the porosity of the cortex. By contrast, the use of eyelash curler did not affect the eyelash structure with statistical significance.

International Workshop on Advanced Dynamics and Model Based Control of Structures and Machines

CERN Document Server

Belyaev, Alexander; Krommer, Michael

2017-01-01

The papers in this volume present and discuss the frontiers in the mechanics of controlled machines and structures. They are based on papers presented at the International Workshop on Advanced Dynamics and Model Based Control of Structures and Machines held in Vienna in September 2015. The workshop continues a series of international workshops held in Linz (2008) and St. Petersburg (2010).

Magnetic properties of tetrataenite-rich meteorites. Pt. 2

International Nuclear Information System (INIS)

Nagata, T.; Funaki, M.; Danon, J.

1985-01-01

Magnetic hysteresis and thermomagnetic characteristics of St. Severin (LL 6 ), Appley Bridge (LL 6 ) and Tuxtuac (LL 5 ) chondrites, which contain tetrataenite in their metallic components, are measured and analyzed in comparison with another tetrataenite-rich chondrite, Yamato 74160. The magnetic properties of tetrataenite-rich meteorites are characterized by (a) high magnetic coercive force (H sub(C)) which amounts to 520 Oe for St. Severin and 160 Oe for Appley Bridge, (b) essential flatness up to about 500 0 C and then a sharp irreversible drop down to Curie point of the first-run heating thermomagnetic curve. Both characteristic features are broken down to the ordinary features of disordered taenite by a breakdown of tetrataenite structure at elevated temperatures beyond the order-disorder transition temperature. The natural remanent magnetization (NRM) of tetrataenite-rich meteorites is extremely stable against AF-demagnetization and other magnetic disturbances because of the high magnetic coercivity of tetrataenite. The breakdown processes of ordered tetrataenite structure by heat treatments are experimentally pursued for the purpose of research of a possible formation process of tetrataenite phase in meteorites. (Author) [pt

Impaired rich club and increased local connectivity in children with traumatic brain injury: Local support for the rich?

Science.gov (United States)

Verhelst, Helena; Vander Linden, Catharine; De Pauw, Toon; Vingerhoets, Guy; Caeyenberghs, Karen

2018-03-12

Recent evidence has shown the presence of a "rich club" in the brain, which constitutes a core network of highly interconnected and spatially distributed brain regions, important for high-order cognitive processes. This study aimed to map the rich club organization in 17 young patients with moderate to severe TBI (15.71 ± 1.75 years) in the chronic stage of recovery and 17 age- and gender-matched controls. Probabilistic tractography was performed on diffusion weighted imaging data to construct the edges of the structural connectomes using number of streamlines as edge weight. In addition, the whole-brain network was divided into a rich club network, a local network and a feeder network connecting the latter two. Functional outcome was measured with a parent questionnaire for executive functioning. Our results revealed a significantly decreased rich club organization (p values < .05) and impaired executive functioning (p < .001) in young patients with TBI compared with controls. Specifically, we observed reduced density values in all three subnetworks (p values < .005) and a reduced mean strength in the rich club network (p = .013) together with an increased mean strength in the local network (p = .002) in patients with TBI. This study provides new insights into the nature of TBI-induced brain network alterations and supports the hypothesis that the local subnetwork tries to compensate for the biologically costly subnetwork of rich club nodes after TBI. © 2018 Wiley Periodicals, Inc.

INTERDEPENDENCIES OF THE INTERNAL / MANAGERIAL CONTROL STANDARD NO. 6 - ORGANIZATIONAL STRUCTURE

Directory of Open Access Journals (Sweden)

Ionut-Cosmin BĂLOI

2015-06-01

Full Text Available Our initiative of analyzing the internal control standard which deals with the organizational structure comes from the observations on the significance of these essential aspects of modern management and on the sensitivity with which this standard is treated in most of the public institutions considered representative for the Oltenia region. Although the administrators of public institutions strive to optimize the systems of internal/managerial control, they frequently face many issues concerning the misunderstanding of these standards, vaguely explained, for example throughout some guidelines or other documents. The hypothesis of our study is that most of public institutions face gaps in understanding, interpreting, adapting and implementing an effective model of organizational structure, and the causes are due to the lack of an interdependent, correlated approach of the pillars that support the internal/managerial control system: the 25 standards required by the Romanian legislation. Our study critically describes the superficial approach founded in the self-evaluation reports of the public institutions, if we refer only to the conformity of the organizational structure and the four standards that we consider inextricably related with this internal/managerial control standard. From the methodological point of view, our study tests the correlation between the level of compliance of these standards and the functionality of the system composed by them in the public organizations that we have investigated.

Virtual Field and Internal Structure of Half-Dressed Extended Particles

International Nuclear Information System (INIS)

Compagno, G.; Persico, F.

1988-01-01

A new method is proposed to investigate the internal geometrical structure of an extended particle surrounded by an incomplete virtual dressing field. This method involves analysing the time-dependent virtual field at large distances from the particle, without any direct interaction with the latter. As an example, the pulselike, time-dependent virtual field of an extended QED source is investigated using a model which has a well-known counterpart in meson theory. In the framework of nonrelativistic QED it is shown that, contrary to the case of a point source, the pulse has finite width and height. For the case of a spherically symmetric source, it is explicitly shown that the width and shape of the pulse at distance r from the particle depend on the parameters determining the space structure of the source. It is concluded that the study of the field of half-dressed particles may provide a new method to investigate their internal structure

Impaired intracortical transmission in G2019S leucine rich-repeat kinase Parkinson patients.

Science.gov (United States)

Ponzo, Viviana; Di Lorenzo, Francesco; Brusa, Livia; Schirinzi, Tommaso; Battistini, Stefania; Ricci, Claudia; Sambucci, Manolo; Caltagirone, Carlo; Koch, Giacomo

2017-05-01

A mutation in leucine-rich repeat kinase 2 is the most common cause of hereditary Parkinson's disease (PD), yet the neural mechanisms and the circuitry potentially involved are poorly understood. We used different transcranial magnetic stimulation protocols to explore in the primary motor cortex the activity of intracortical circuits and cortical plasticity (long-term potentiation) in patients with the G2019S leucine-rich repeat kinase 2 gene mutation when compared with idiopathic PD patients and age-matched healthy subjects. Paired pulse transcranial magnetic stimulation was used to investigate short intracortical inhibition and facilitation and short afferent inhibition. Intermittent theta burst stimulation, a form of repetitive transcranial magnetic stimulation, was used to test long-term potentiation-like cortical plasticity. Leucine-rich repeat kinase 2 and idiopathic PD were tested both in ON and in OFF l-dopa therapy. When compared with idiopathic PD and healthy subjects, leucine-rich repeat kinase 2 PD patients showed a remarkable reduction of short intracortical inhibition in both ON and in OFF l-dopa therapy. This reduction was paralleled by an increase of intracortical facilitation in OFF l-dopa therapy. Leucine-rich repeat kinase 2 PD showed abnormal long-term potentiation-like cortical plasticity in ON l-dopa therapy. The motor cortex in leucine-rich repeat kinase 2 mutated PD patients is strongly disinhibited and hyperexcitable. These abnormalities could be a result of an impairment of inhibitory (gamma-Aminobutyric acid) transmission eventually related to altered neurotransmitter release. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.

Co-ordination of the international network of nuclear structure and decay data evaluators

International Nuclear Information System (INIS)

Schmidt, J.J.

1988-10-01

The IAEA Nuclear Data Section convened the eighth meeting of the international nuclear structure and decay data network at Ghent, Belgium, 16-20 May 1988. The meeting was attended by 21 scientists from 12 Member States and three international organizations, concerned with the compilation, evaluation, and dissemination of nuclear structure and decay data. This document contains a summary of the meeting, the proceedings of the meeting and in appendices status reports of activities in nuclear structure and decay data from the participating centers. Refs and tabs

Calculation of DPA in the Reactor Internal Structural Materials of Nuclear Power Plant

International Nuclear Information System (INIS)

Kim, Yong Deong; Lee, Hwan Soo

2014-01-01

The embrittlement is mainly caused by atomic displacement damage due to irradiations with neutrons, especially fast neutrons. The integrity of the reactor internal structural materials has to be ensured over the reactor life time, threatened by the irradiation induced displacement damage. Accurate modeling and prediction of the displacement damage is a first step to evaluate the integrity of the reactor internal structural materials. Traditional approaches for analyzing the displacement damage of the materials have relied on tradition model, developed initially for simple metals, Kinchin and Pease (K-P), and the standard formulation of it by Norgett et al. , often referred to as the 'NRT' model. An alternative and complementary strategy for calculating the displacement damage is to use MCNP code. MCNP uses detailed physics and continuous-energy cross-section data in its simulations. In this paper, we have performed the evaluation of the displacement damage of the reactor internal structural materials in Kori NPP unit 1 using detailed Monte Carlo modeling and compared with predictions results of displacement damage using the classical NRT model. The evaluation of the displacement damage of the reactor internal structural materials in Kori NPP unit 1 using detailed Monte Carlo modeling has been performed. The maximum value of the DPA rate was occurred at the baffle side of the reactor internal where the node has the maximum neutron flux

The richness and reach of Wikinomics: Is the free web-based encyclopedia Wikipedia only for the rich countries?

DEFF Research Database (Denmark)

Rask, Morten

2007-01-01

In this paper, a model of the patterns of correlation in Wikipedia, reach and richness, lays the foundation for studying whether or not the free web-based encyclopedia Wikipedia is only for developed countries. Based upon data from 12 different Wikipedia language editions, we find that the central...... structural effect is on the level of human development in the current country. In other words, Wikipedia is in general, more for rich countries than for less developed countries. It is suggested that policy makers make investments in increasing the general level of literacy, education, and standard of living...

Verification of Remote Inspection Techniques for Reactor Internal Structures of Liquid Metal Reactor

International Nuclear Information System (INIS)

Joo, Young Sang; Lee, Jae Han

2007-02-01

The reactor internal structures and components of a liquid metal reactor (LMR) are submerged in hot sodium of reactor vessel. The division 3 of ASME code section XI specifies the visual inspection as major in-service inspection (ISI) methods of reactor internal structures and components. Reactor internals of LMR can not be visually examined due to opaque liquid sodium. The under-sodium viewing techniques using an ultrasonic wave should be applied for the visual inspection of reactor internals. Recently, an ultrasonic waveguide sensor with a strip plate has been developed for an application to the under-sodium inspection. In this study, visualization technique, ranging technique and monitoring technique have been suggested for the remote inspection of reactor internals by using the waveguide sensor. The feasibility of these remote inspection techniques using ultrasonic waveguide sensor has been evaluated by an experimental verification

Verification of Remote Inspection Techniques for Reactor Internal Structures of Liquid Metal Reactor

Energy Technology Data Exchange (ETDEWEB)

Joo, Young Sang; Lee, Jae Han

2007-02-15

The reactor internal structures and components of a liquid metal reactor (LMR) are submerged in hot sodium of reactor vessel. The division 3 of ASME code section XI specifies the visual inspection as major in-service inspection (ISI) methods of reactor internal structures and components. Reactor internals of LMR can not be visually examined due to opaque liquid sodium. The under-sodium viewing techniques using an ultrasonic wave should be applied for the visual inspection of reactor internals. Recently, an ultrasonic waveguide sensor with a strip plate has been developed for an application to the under-sodium inspection. In this study, visualization technique, ranging technique and monitoring technique have been suggested for the remote inspection of reactor internals by using the waveguide sensor. The feasibility of these remote inspection techniques using ultrasonic waveguide sensor has been evaluated by an experimental verification.

Probing the internal structure of the asteriod Didymoon with a passive seismic investigation

Science.gov (United States)

Murdoch, N.; Hempel, S.; Pou, L.; Cadu, A.; Garcia, R. F.; Mimoun, D.; Margerin, L.; Karatekin, O.

2017-09-01

Understanding the internal structure of an asteroid has important implications for interpreting its evolutionary history, for understanding its continuing geological evolution, and also for asteroid deflection and in-situ space resource utilisation. Given the strong evidence that asteroids are seismically active, an in-situ passive seismic experiment could provide information about the asteroid surface and interior properties. Here, we discuss the natural seismic activity that may be present on Didymoon, the secondary component of asteroid (65803) Didymos. Our analysis of the tidal stresses in Didymoon shows that tidal quakes are likely to occur if the secondary has an eccentric orbit. Failure occurs most easily at the asteroid poles and close to the surface for both homogeneous and layered internal structures. Simulations of seismic wave propagation in Didymoon show that the seismic moment of even small meteoroid impacts can generate clearly observable body and surface waves if the asteroid's internal structure is homogeneous. The presence of a regolith layer over a consolidated core can result in the seismic energy becoming trapped in the regolith due to the strong impedance contrast at the regolith-core boundary. The inclusion of macro-porosity (voids) further complexifies the wavefield due to increased scattering. The most prominent seismic waves are always found to be those traveling along the surface of the asteroid and those focusing in the antipodal point of the seismic source. We find also that the waveforms and ground acceleration spectra allow discrimination between the different internal structure models. Although the science return of a passive seismic experiment would be enhanced by having multiple seismic stations, one single seismic station can already vastly improve our knowledge about the seismic environment and sub-surface structure of an asteroid. We describe several seismic measurement techniques that could be applied in order to study the

Structural and optical properties of silicon rich oxide films in graded-stoichiometric multilayers for optoelectronic devices

Energy Technology Data Exchange (ETDEWEB)

Palacios-Huerta, L.; Aceves-Mijares, M. [Electronics Department, INAOE, Apdo. 51, Puebla, Pue. 72000, México (Mexico); Cabañas-Tay, S. A.; Cardona-Castro, M. A.; Morales-Sánchez, A., E-mail: alfredo.morales@cimav.edu.mx [Centro de Investigación en Materiales Avanzados S.C., Unidad Monterrey-PIIT, Apodaca, NL 66628, México (Mexico); Domínguez-Horna, C. [Instituto de Microelectrónica de Barcelona, IMB-CNM (CSIC), Bellaterra 08193, Barcelona (Spain)

2016-07-18

Silicon nanocrystals (Si-ncs) are excellent candidates for the development of optoelectronic devices. Nevertheless, different strategies are still necessary to enhance their photo and electroluminescent properties by controlling their structural and compositional properties. In this work, the effect of the stoichiometry and structure on the optical properties of silicon rich oxide (SRO) films in a multilayered (ML) structure is studied. SRO MLs with silicon excess gradually increased towards the top and bottom and towards the center of the ML produced through the variation of the stoichiometry in each SRO layer were fabricated and confirmed by X-ray photoelectron spectroscopy. Si-ncs with three main sizes were observed by a transmission electron microscope, in agreement with the stoichiometric profile of each SRO layer. The presence of the three sized Si-ncs and some oxygen related defects enhances intense violet/blue and red photoluminescence (PL) bands. The SRO MLs were super-enriched with additional excess silicon by Si{sup +} implantation, which enhanced the PL intensity. Oxygen-related defects and small Si-ncs (<2 nm) are mostly generated during ion implantation enhancing the violet/blue band to become comparable to the red band. The structural, compositional, and luminescent characteristics of the multilayers are the result of the contribution of the individual characteristics of each layer.

Large-scale micromagnetic simulation of Nd-Fe-B sintered magnets with Dy-rich shell structures

Directory of Open Access Journals (Sweden)

T. Oikawa

2016-05-01

Full Text Available Large-scale micromagnetic simulations have been performed using the energy minimization method on a model with structural features similar to those of Dy grain boundary diffusion (GBD-processed sintered magnets. Coercivity increases as a linear function of the anisotropy field of the Dy-rich shell, which is independent of Dy composition in the core as long as the shell thickness is greater than about 15 nm. This result shows that the Dy contained in the initial sintered magnets prior to the GBD process is not essential for enhancing coercivity. Magnetization reversal patterns indicate that coercivity is strongly influenced by domain wall pinning at the grain boundary. This observation is found to be consistent with the one-dimensional pinning theory.

New experimental investigation of cluster structures in 10 Be and 16 C neutron-rich nuclei

Science.gov (United States)

Dell'Aquila, L.; Acosta, D.; Auditore, L.; Cardella, G.; De Filippo, E.; De Luca, S.; Francalanza, L.; Gnoffo, B.; Lanzalone, G.; Lombardo, I.; Martorana, N. S.; Norella, S.; Pagano, A.; Pagano, E. V.; Papa, M.; Pirrone, S.; Politi, G.; Quattrocchi, L.; Rizzo, F.; Russotto, P.; Trifirò, A.; Trimarchi, M.; Verde, G.; Vigilante, M.

2017-11-01

The existence of cluster structures in ^{10} Be and ^{16} C neutron-rich isotopes is investigated via projectile break-up reactions induced on polyethylene (CH _2 target. We used a fragmentation beam constituted by 55MeV/u ^{10} Be and 49MeV/u ^{16} C beams provided by the FRIBs facility at INFN-LNS. Invariant mass spectra of 4{He}+ 6 He and 6{He} + ^{10} Be breakup fragments are reconstructed by means of the CHIMERA 4π detector to investigate the presence of excited states of projectile nuclei characterized by cluster structure. In the first case, we suggest the presence of a new state in ^{10} Be at 13.5MeV. A non-vanishing yield corresponding to 20.6MeV excitation energy of ^{16} C was observed in the 6{He} + ^{10} Be cluster decay channel. To improve the results of the present analysis, a new experiment has been performed recently, taking advantage of the coupling of CHIMERA and FARCOS. In the paper we describe the data reduction process of the new experiment together with preliminary results.

Two genetic loci produce distinct carbohydrate-rich structural components of the Pseudomonas aeruginosa biofilm matrix.

Science.gov (United States)

Friedman, Lisa; Kolter, Roberto

2004-07-01

Pseudomonas aeruginosa forms biofilms, which are cellular aggregates encased in an extracellular matrix. Molecular genetics studies of three common autoaggregative phenotypes, namely wrinkled colonies, pellicles, and solid-surface-associated biofilms, led to the identification of two loci, pel and psl, that are involved in the production of carbohydrate-rich components of the biofilm matrix. The pel gene cluster is involved in the production of a glucose-rich matrix material in P. aeruginosa strain PA14 (L. Friedman and R. Kolter, Mol. Microbiol. 51:675-690, 2004). Here we investigate the role of the pel gene cluster in P. aeruginosa strain ZK2870 and identify a second genetic locus, termed psl, involved in the production of a mannose-rich matrix material. The 11 predicted protein products of the psl genes are homologous to proteins involved in carbohydrate processing. P. aeruginosa is thus able to produce two distinct carbohydrate-rich matrix materials. Either carbohydrate-rich matrix component appears to be sufficient for mature biofilm formation, and at least one of them is required for mature biofilm formation in P. aeruginosa strains PA14 and ZK2870. Copyright 2004 American Society for Microbiology

The structure of neutron-rich nuclei explored via in-beam gamma-ray spectroscopy of fast beams

International Nuclear Information System (INIS)

Glasmacher, T.; Campbell, C.M.; Church, J.A.; Dinca, D.C.; Hansen, P.G.; Olliver, H.; Perry, B.C.; Sherrill, B.M.; Terry, J.R.; Bazin, D.; Enders, J.; Gade, A.; Hu, Z.; Mueller, W.F.

2003-01-01

In-beam gamma-ray spectroscopy with fast exotic beams provides an efficient tool to study bound states in exotic neutron-rich nuclei. Specialized experimental techniques have been developed and explore different aspects of nuclear structure. Inelastic scattering experiments with γ-ray detection can measure the response of exotic nuclei to electromagnetic (Coulomb excitation with a heavy target) or hadronic probes (proton scattering with hydrogen target). In-beam fragmentation populates higher-lying bound states to establish levels. Single- and two-nucleon knockout reactions allow for detailed wavefunction spectroscopy of individual levels and for the measurement of spectroscopic factors. Experimental programs employing these techniques are now underway at all projectile-fragmentation facilities around the world. Here we report on several successful in-beam gamma-ray spectroscopy experiments that have been performed at the Coupled Cyclotron Facility at Michigan State University with an emphasis on elucidating the evolution of nuclear structure around neutron numbers N=16, N=20, and N=28 in the π(sd) shell. (orig.)

Experimental study of the structure of rich premixed 1,3-butadiene/CH4/O2/Ar flame.

OpenAIRE

Gueniche , Hadj-Ali; Glaude , Pierre-Alexandre; Fournet , René; Battin-Leclerc , Frédérique

2006-01-01

traduit de Fizika Goreniya I Vzryva, 2006, 42, 89-95.; The structure of a laminar rich premixed 1,3-C4H6/CH4/O2/Ar flame have been investigated. 1,3-Butadiene, methane, oxygen and argon mole fractions are 0.033; 0.2073; 0.3315, and 0.4280, respectively, for an equivalent ratio of 1.80. The flame has been stabilized on a burner at a pressure of 6.7 kPa (50 Torr). The concentration profiles of stable species were measured by gas chromatography after sampling with a quartz probe. Quantified spec...

A new international health order. An inquiry into the international relations of world health and medical care

NARCIS (Netherlands)

Pannenborg, Charles Olke

1978-01-01

A 'New International Health Order' (NIHO) is a new notion. In order to value the function of a NIHO, the present international health order and the socioeconomic order between the rich and poor countries will have to be taken into account. The factual and normatived evelopment of a new international

External and internal structure of weevils (Insecta: Coleoptera) investigated with phase-contrast X-ray imaging

International Nuclear Information System (INIS)

Hoennicke, M.G.; Cusatis, C.; Rigon, L.; Menk, R.-H.; Arfelli, F.; Foerster, L.A.; Rosado-Neto, G.H.

2010-01-01

Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures (Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature.

Ultimate internal pressure capacity of concrete containment structures

International Nuclear Information System (INIS)

Krishnaswamy, C.N.; Namperumal, R.; Al-Dabbagh, A.

1983-01-01

Lesson learned from the accident at Three-Mile Island nuclear plant has necessitated the computation of the ultimate internal pressure capacity of containment structures as a licensing requirement in the U.S. In general, a containment structure is designed to be essentially elastic under design accident pressure. However, as the containment pressure builds up beyond the design value due to a more severe postulated accident, the containment response turns nonlinear as it sequentially passes through cracking of concrete, yielding of linear plate, yielding of rebar, and yielding of post-tensioning tendon (if the containment concrete is prestressed). This paper reports on the determination of the ultimate internal pressure capacity and nonlinear behavior of typical reinforced and prestressed concrete BWR containments. The probable modes of failure, the criteria for ultimate pressure capacity, and the most critical sections are described. Simple equations to hand-calculate the ultimate pressure capacity and the nonlinear behavior at membrane sections of the containment shell are presented. A nonlinear finite element analysis performed to determine the nonlinear behavior of the entire shell including nonmembrane sections is briefly discribed. The analysis model consisted of laminated axisymmetric shell finite elements with nonlinear stress-strain properties for each material. Results presented for typical BWR concrete containments include nonlinear response plots of internal pressure versus containment deflection and strains in the liner, rebar, and post-tensioning tendons at the most stressed section in the shell. Leak-tightness of the containment liner and the effect of thermal loads on the ultimate capacity are discussed. (orig.)

Investigations of internal noise levels for different target sizes, contrasts, and noise structures

Science.gov (United States)

Han, Minah; Choi, Shinkook; Baek, Jongduk

2014-03-01

To describe internal noise levels for different target sizes, contrasts, and noise structures, Gaussian targets with four different sizes (i.e., standard deviation of 2,4,6 and 8) and three different noise structures(i.e., white, low-pass, and highpass) were generated. The generated noise images were scaled to have standard deviation of 0.15. For each noise type, target contrasts were adjusted to have the same detectability based on NPW, and the detectability of CHO was calculated accordingly. For human observer study, 3 trained observers performed 2AFC detection tasks, and correction rate, Pc, was calculated for each task. By adding proper internal noise level to numerical observer (i.e., NPW and CHO), detectability of human observer was matched with that of numerical observers. Even though target contrasts were adjusted to have the same detectability of NPW observer, detectability of human observer decreases as the target size increases. The internal noise level varies for different target sizes, contrasts, and noise structures, demonstrating different internal noise levels should be considered in numerical observer to predict the detection performance of human observer.

Internal Evaluation, Historically Speaking

Science.gov (United States)

Mathison, Sandra

2011-01-01

The author analyzes the growth and nature of internal evaluation from the 1960s to the present and suggests that internal evaluation has been on the increase because of its perceived importance. Although the 1960s were characterized by a rich intellectual development of evaluation theory and practice, the fiscal conservatism of the 1980s ushered…

Thermo-Elastic Analysis of Internally Cooled Structures Using a Higher Order Theory

Science.gov (United States)

Arnold, Steven M.; Bednarcyk, Brett A.; Aboudi, Jacob

2001-01-01

This paper presents the results of a study on the thermomechanical behavior of internally cooled silicon nitride structures. Silicon nitride is under consideration for elevated temperature aerospace engine applications. and techniques for lowering the operating temperature of structures composed of this material are under development. Lowering the operating temperature provides a large payoff in terms of fatigue life and may be accomplished through the use of thermal barrier coatings (TBC's) and the novel concept of included cooling channels. Herein, an in-depth study is performed on the behavior of a flame-impinged silicon nitride plate with a TBC and internal channels cooled by forced air. The analysis is performed using the higher order theory for functionally graded materials (HOTFGM), which has been developed through NASA Glenn Research Center funding over the past several years. HOTFGM was chosen over the traditional finite element approach as a prelude to an examination of functionally graded silicon nitride structures for which HOTFGM is ideally suited. To accommodate the analysis requirement% of the internally cooled plate problem, two crucial enhancements were made to the two-dimensional Cartesian-based version of HOTFGM. namely, incorporation of internal boundary capabilities and incorporation of convective boundary conditions. Results indicate the viability and large benefits of cooling the plate via forced air through cooling channels. Furthermore, cooling can positively impact the stress and displacement fields present in the plate, yielding an additional payoff in terms of fatigue life. Finally, a spin-off capability resulted from inclusion of internal boundaries within HOTFGM; the ability to simulate the thermo-elastic response of structures with curved surfaces. This new capability is demonstrated, and through comparison with an analytical solution, shown to be viable and accurate.

Effect of gamma irradiation on the structure of corn stalks and their subsequent bioconversion into protein-rich mycelial biomass of pleurotus sajor-caju

Energy Technology Data Exchange (ETDEWEB)

Awafo, V [Quebec Univ., Montreal, PQ (Canada)

1994-12-31

Lignocellulosic biomass like corn stalk is an abundant and renewable resource from which food, feed and chemicals may be derived. Enzymatic hydrolysis of native lignocellulosic material is prohibitively slow due to their compositional heterogeneity and structural complexity. In this work, ground corn stalks (20 mesh) were subjected to gamma irradiation (10-170 Mrads) as pretreatments to make them more susceptible for bioconversion into protein-rich mycelial biomass of Pleurotus sajor-caju NRRL 18757. The irradiation was carried out in air in a {sup 60}Co Underwater Calibrator (UC-15, Nordion International) at a dose rate of 2.5 Mrads/h as measured by Fricke dosimetry. No apparent structural differences were observed under the light microscope. However, the protein synthesis and the proportion of mycelial biomass increased with the increase in both the dose of irradiation and time of fermentation during the bioconversion of 1% corn stalk into mycelial biomass of Pleurotus sajor-caju. Gamma irradiation at the dose of 50 Mrads or lower did not produce any appreciable increase in the amount of protein synthesised. At 170 Mrads, the final product contained 28% protein representing a 2-fold increase from non-irradiated corn stalk and an efficiency of 36% conversion of total utilizable polysaccharides of corn stalks into mycelial biomass. The lag phase during mycelial biomass production was much more prolonged at very high doses indicating possible production of some toxic substances during irradiation. (author). 2 tabs., 6 figs.

The international uranium market - structure and outlook

International Nuclear Information System (INIS)

Noreng, Oe.

1978-01-01

It is pointed out that the international uranium market is immature and is subject to factors of a political, rather than economic nature. This is due largely to potential military exploitation, which has led USA, Canada and Australia to adopt a restrictive export policy. South Africa and France, on the other hand have a more liberal attitude. The history of the market, and the development of U308 prices are then discussed and related to the phases in the commercial exploitation of nuclear power. The present market structure is described, both international and within Canada, USA, Australia, South Africa and France. The future demand is then discussed, assuming three levels of demand and various price categories. It is shown that the demand will be only slightly influenced by moderate to large increases in price, assuming price rises for coal and oil. It is concluded that the price can rise to $400-500/pound U308. (JIW)

Utilization of paramagnetic relaxation enhancements for high-resolution NMR structure determination of a soluble loop-rich protein with sparse NOE distance restraints

International Nuclear Information System (INIS)

Furuita, Kyoko; Kataoka, Saori; Sugiki, Toshihiko; Hattori, Yoshikazu; Kobayashi, Naohiro; Ikegami, Takahisa; Shiozaki, Kazuhiro; Fujiwara, Toshimichi; Kojima, Chojiro

2015-01-01

NMR structure determination of soluble proteins depends in large part on distance restraints derived from NOE. In this study, we examined the impact of paramagnetic relaxation enhancement (PRE)-derived distance restraints on protein structure determination. A high-resolution structure of the loop-rich soluble protein Sin1 could not be determined by conventional NOE-based procedures due to an insufficient number of NOE restraints. By using the 867 PRE-derived distance restraints obtained from the NOE-based structure determination procedure, a high-resolution structure of Sin1 could be successfully determined. The convergence and accuracy of the determined structure were improved by increasing the number of PRE-derived distance restraints. This study demonstrates that PRE-derived distance restraints are useful in the determination of a high-resolution structure of a soluble protein when the number of NOE constraints is insufficient

Cysteine-Rich Peptide Family with Unusual Disulfide Connectivity from Jasminum sambac.

Science.gov (United States)

Kumari, Geeta; Serra, Aida; Shin, Joon; Nguyen, Phuong Q T; Sze, Siu Kwan; Yoon, Ho Sup; Tam, James P

2015-11-25

Cysteine-rich peptides (CRPs) are natural products with privileged peptidyl structures that represent a potentially rich source of bioactive compounds. Here, the discovery and characterization of a novel plant CRP family, jasmintides from Jasminum sambac of the Oleaceae family, are described. Two 27-amino acid jasmintides (jS1 and jS2) were identified at the gene and protein levels. Disulfide bond mapping of jS1 by mass spectrometry and its confirmation by NMR spectroscopy revealed disulfide bond connectivity of C-1-C-5, C-2-C-4, and C-3-C-6, a cystine motif that has not been reported in plant CRPs. Structural determination showed that jS1 displays a well-defined structure framed by three short antiparallel β-sheets. Genomic analysis showed that jasmintides share a three-domain precursor arrangement with a C-terminal mature domain preceded by a long pro-domain of 46 residues and an intron cleavage site between the signal sequence and pro-domain. The compact cysteine-rich structure together with an N-terminal pyroglutamic acid residue confers jasmintides high resistance to heat and enzymatic degradation, including exopeptidase treatment. Collectively, these results reveal a new plant CRP structure with an unusual cystine connectivity, which could be useful as a scaffold for designing peptide drugs.

Internal structure of black holes

International Nuclear Information System (INIS)

Cvetic, Mirjam

2013-01-01

Full text: We review recent progress that sheds light on the internal structure of general black holes. We first summarize properties of general multi-charged rotating black holes both in four and five dimensions. We show that the asymptotic boundary conditions of these general asymptotically flat black holes can be modified such that a conformal symmetry emerges. These subtracted geometries preserve the thermodynamic properties of the original black holes and are of the Lifshitz type, thus describing 'a black hole in the asymptotically conical box'. Recent efforts employ solution generating techniques to construct interpolating geometries between the original black hole and their subtracted geometries. Upon lift to one dimension higher, these geometries lift to AdS 3 times a sphere, and thus provide a microscopic interpretation of the black hole entropy in terms of dual two-dimensional conformal field theory. (author)

The changing structure of the international commercial nuclear power reactor industry

International Nuclear Information System (INIS)

Forsberg, C.W.; Hill, L.J.; Reich, W.J.; Rowan, W.J.

1992-12-01

The objective of this report is to provide an understanding of the international commercial nuclear power industry today and how the industry is evolving. This industry includes reactor vendors, product lines, and utility customers. The evolving structure of the international nuclear power reactor industry implies different organizations making decisions within the nuclear power industry, different outside constraints on those decisions, and different priorities than with the previous structure. At the same time, cultural factors, technical constraints, and historical business relationships allow for an understanding of the organization of the industry, what is likely, and what is unlikely. With such a frame of reference, current trends and future directions can be more readily understood

Development and internal structure investigation of the Dimensional Clinical Personality Inventory

Directory of Open Access Journals (Sweden)

Lucas de Francisco Carvalho

2015-06-01

Full Text Available This study aimed to develop a dimensional instrument to assess personality disorders based on Millon's theoretical perspective and on DSM-IV-TR diagnoses criteria, and seek validity evidence based on internal structure and reliability indexes of the factors. In order to do that, a self-report test composed of 215 items, the Dimensional Clinical Personality Inventory (DCPI was developed and applied to 561 respondents aged between 18 and 90 years (M = 28,8; SD = 11.4, with 51.8% females. Exploratory factor analysis and verification of reliability were performed using Cronbach's alpha. Data provided validity evidence based on internal structure of the instrument according to the theory of Millon and DSM-IV-TR.

Platelet-rich fibrin or platelet-rich plasma – which one is better? an opinion

Directory of Open Access Journals (Sweden)

Shweta Bansal

2017-01-01

Full Text Available The healing of hard and soft tissue in mediated by a wide range of intracellular and extracellular events that are regulated by signaling proteins. Platelets can play a crucial role in periodontal regeneration as they are the reservoirs of growth factors and cytokines which are the key factors for regeneration of bone and maturation of soft tissue. Platelet-rich plasma (PRP is first generation platelet concentrate. However, the short duration of cytokine release and its poor mechanical properties have resulted in search of new material. Platelet-rich fibrin (PRF is a natural fibrin-based biomaterial prepared from an anticoagulant-free blood harvest without any artificial biochemical modification (no bovine thrombin is required that allows obtaining fibrin membranes enriched with platelets and growth factors. The slow polymerization during centrifugation, fibrin-based structure, ease of preparation, minimal expense makes PRF somewhat superior in some aspect to PRP.

An investigation of structural design methodology for HTGR reactor internals with ceramic materials (Contract research)

International Nuclear Information System (INIS)

Sumita, Junya; Shibata, Taiju; Nakagawa, Shigeaki; Iyoku, Tatsuo; Sawa, Kazuhiro

2008-03-01

To advance the performance and safety of HTGR, heat-resistant ceramic materials are expected to be used as reactor internals of HTGR. C/C composite and superplastic zirconia are the promising materials for this purpose. In order to use these new materials as reactor internals in HTGR, it is necessary to establish a structure design method to guarantee the structural integrity under environmental and load conditions. Therefore, C/C composite expected as reactor internals of VHTR is focused and an investigation on the structural design method applicable to the C/C composite and a basic applicability of the C/C composite to representative structures of HTGR were carried out in this report. As the results, it is found that the competing risk theory for the strength evaluation of the C/C composite is applicable to design method and C/C composite is expected to be used as reactor internals of HTGR. (author)

Synthesis, crystal structure investigation and magnetism of the complex metal-rich boride series Cr{sub x}(Rh{sub 1-y}Ru{sub y}){sub 7-x}B{sub 3} (x=0.88-1; y=0-1) with Th{sub 7}Fe{sub 3}-type structure

Energy Technology Data Exchange (ETDEWEB)

Misse, Patrick R.N.; Mbarki, Mohammed [Institute of Inorganic Chemistry, RWTH Aachen University, 52066 Aachen (Germany); Fokwa, Boniface P.T., E-mail: boniface.fokwa@ac.rwth-aachen.de [Institute of Inorganic Chemistry, RWTH Aachen University, 52066 Aachen (Germany)

2012-08-15

Powder samples and single crystals of the new complex boride series Cr{sub x}(Rh{sub 1-y}Ru{sub y}){sub 7-x}B{sub 3} (x=0.88-1; y=0-1) have been synthesized by arc-melting the elements under purified argon atmosphere on a water-cooled copper crucible. The products, which have metallic luster, were structurally characterized by single-crystal and powder X-ray diffraction as well as EDX measurements. Within the whole solid solution range the hexagonal Th{sub 7}Fe{sub 3} structure type (space group P6{sub 3}mc, no. 186, Z=2) was identified. Single-crystal structure refinement results indicate the presence of chromium at two sites (6c and 2b) of the available three metal Wyckoff sites, with a pronounced preference for the 6c site. An unexpected Rh/Ru site preference was found in the Ru-rich region only, leading to two different magnetic behaviors in the solid solution: The Rh-rich region shows a temperature-independent (Pauli) paramagnetism whereas an additional temperature-dependent paramagnetic component is found in the Ru-rich region. - Graphical abstract: The new complex boride series Cr{sub x}(Rh{sub 1-y}Ru{sub y}){sub 7-x}B{sub 3} (x=0.88-1; y=0-1) has been synthesized by arc melting the elements under purified argon atmosphere. Beside the 3d/4d site preference within the whole solid solution, an unexpected Rh/Ru site preference was found in the Ru-rich region only, leading to two different magnetic behaviors: The Rh-rich region shows a temperature-independent (Pauli) paramagnetism whereas an additional temperature-dependent paramagnetic component is found in the Ru-rich region. Highlights: Black-Right-Pointing-Pointer Synthesis of a new boride series fulfilling Vegard Acute-Accent s rule. Black-Right-Pointing-Pointer 3d/4d site preference. Black-Right-Pointing-Pointer Unexpected Ru/Rh site preference. Black-Right-Pointing-Pointer Rh-rich region is Pauli paramagnetic. Black-Right-Pointing-Pointer Ru-rich region is Pauli and temperature-dependent paramagnetic.

Structure and properties of rare earth-rich glassed for nuclear waste immobilisation

International Nuclear Information System (INIS)

Bardez, I.

2004-11-01

A new nuclear glass composition, able to immobilize highly radioactive liquid wastes from high burn-up UO 2 fuel, was established and its structure studied. The composition of the selected rare earth-rich glass is (molar %): 61.79 SiO 2 - 8.94 B 2 O 3 - 3.05 Al 2 O 3 - 14.41 Na 2 O - 6.32 CaO - 1.89 ZrO 2 - 3.60 RE 2 O 3 (with RE = La, Ce, Pr and Nd). The aim of this study was to determine the local environment of the rare earth in this glass and also to glean information about the effect of glass composition on the rare earth neighbouring (influence of Si, B, Al, Na and Ca contents). To this end, several series of glasses, prepared from the baseline glass, were studied by different characterisation methods such as EXAFS spectroscopy at the neodymium LIII-edge, optical absorption spectroscopy, Raman spectroscopy and 29 Si, 27 Al and 11 B MAS-NMR. By coupling all the results obtained, several hypotheses about the nature of the rare earth neighbouring in the glass were proposed. (author)

pH-Modulated Watson-Crick duplex-quadruplex equilibria of guanine-rich and cytosine-rich DNA sequences 140 base pairs upstream of the c-kit transcription initiation site.

Science.gov (United States)

Bucek, Pavel; Jaumot, Joaquim; Aviñó, Anna; Eritja, Ramon; Gargallo, Raimundo

2009-11-23

Guanine-rich regions of DNA are sequences capable of forming G-quadruplex structures. The formation of a G-quadruplex structure in a region 140 base pairs (bp) upstream of the c-kit transcription initiation site was recently proposed (Fernando et al., Biochemistry, 2006, 45, 7854). In the present study, the acid-base equilibria and the thermally induced unfolding of the structures formed by a guanine-rich region and by its complementary cytosine-rich strand in c-kit were studied by means of circular dichroism and molecular absorption spectroscopies. In addition, competition between the Watson-Crick duplex and the isolated structures was studied as a function of pH value and temperature. Multivariate data analysis methods based on both hard and soft modeling were used to allow accurate quantification of the various acid-base species present in the mixtures. Results showed that the G-quadruplex and i-motif coexist with the Watson-Crick duplex over the pH range from 3.0 to 6.5, approximately, under the experimental conditions tested in this study. At pH 7.0, the duplex is practically the only species present.

Structure and electronic properties of InN and In-rich group III-nitride alloys

International Nuclear Information System (INIS)

Walukiewicz, W; III, J W Ager; Yu, K M; Liliental-Weber, Z; Wu, J; Li, S X; Jones, R E; Denlinger, J D

2006-01-01

The experimental study of InN and In-rich InGaN by a number of structural, optical and electrical methods is reviewed. Recent advances in thin film growth have produced single crystal epitaxial layers of InN which are similar in structural quality to GaN films made under similar conditions and which can have electron concentrations below 1 x 10 18 cm -3 and mobilities exceeding 2000 cm 2 (Vs) -1 . Optical absorption, photoluminescence, photo-modulated reflectance and soft x-ray spectroscopy measurements were used to establish that the room temperature band gap of InN is 0.67 ± 0.05 eV. Experimental measurements of the electron effective mass in InN are presented and interpreted in terms of a non-parabolic conduction band caused by the k · p interaction across the narrow gap. Energetic particle irradiation is shown to be an effective method to control the electron concentration, n, in undoped InN. Optical studies of irradiated InN reveal a large Burstein-Moss shift of the absorption edge with increasing n. Fundamental studies of the energy levels of defects in InN and of electron transport are also reviewed. Finally, the current experimental evidence for p-type activity in Mg-doped InN is evaluated. (topical review)

Structure, thermal stability and resistance under external irradiation of rare earths and molybdenum-rich alumino-borosilicate glasses

International Nuclear Information System (INIS)

Chouard, N.

2011-01-01

In France, the highly radioactive nuclear liquid wastes arising from spent nuclear fuel reprocessing (fission products + minor actinides (FPA)) are currently immobilized in an alumino-borosilicate glass called 'R7T7'. In the future, the opportunity of using new alumino-borosilicate glass compositions (HTC glasses) is considered in order to increase the waste loading in glasses and thus significantly decrease the number of glass canisters. However, the increase of the concentration of FPA could lead to the crystallization of rare-earth-rich phases (Ca 2 RE 8 (SiO 4 ) 6 O 2 ) or molybdenum-rich phases (CaMoO 4 , Na 2 MoO 4 ) during melt cooling, which can modify the confinement properties of the glass (chemical durability, self-irradiation resistance..), particularly if they can incorporate radionuclides α or β in their structure. This thesis can be divided into two parts: The first part deals with studying the relationship that can occur between the composition, the structure and the crystallization tendency of simplified seven oxides glasses, belonging to the SiO 2 -B 2 O 3 -Al 2 O 3 -Na 2 O-CaO-MoO 3 -Nd 2 O 3 system and derived from the composition of the HTC glass at 22,5 wt. % in FPA. The impact of the presence of platinoid elements (RuO 2 in our case) on the crystallization of the different phases is also studied. The second part deals with the effect of actinides α decays and more particularly of nuclear interactions essentially coming from recoil nuclei (simulated here by heavy ions external irradiations) on the behaviour under irradiation of an alumino-borosilicate glass containing apatite Ca 2 Nd 8 (SiO 4 ) 6 O 2 crystals, that can incorporate actinides in their structure. Two samples containing apatite crystals with different size are studied, in order to understand the impact of microstructure on the irradiation resistance of this kind of material. (author) [fr

Internal quantum efficiency enhancement of GaInN/GaN quantum-well structures using Ag nanoparticles

DEFF Research Database (Denmark)

Iida, Daisuke; Fadil, Ahmed; Chen, Yuntian

2015-01-01

We report internal quantum efficiency enhancement of thin p-GaN green quantumwell structure using self-assembled Ag nanoparticles. Temperature dependent photoluminescence measurements are conducted to determine the internal quantum efficiency. The impact of excitation power density on the enhance......We report internal quantum efficiency enhancement of thin p-GaN green quantumwell structure using self-assembled Ag nanoparticles. Temperature dependent photoluminescence measurements are conducted to determine the internal quantum efficiency. The impact of excitation power density...

Co-ordination of the international network of nuclear structure and decay data evaluation

International Nuclear Information System (INIS)

Lemmel, H.D.

1991-11-01

The IAEA Nuclear Data Section convened the ninth meeting of the international nuclear structure and decay data network at Kuwait, 10-14 March 1990. The meeting was attended by 19 scientists from 9 Member States and two international organizations, concerned with the compilation, evaluation, and dissemination of nuclear structure and decay data. The document contains a summary and the proceedings of the meeting, and in annexes, status reports of activities in nuclear structure and decay data from the participating centers. A separate abstract was prepared for one of the scientific lectures related to the topics of the meeting which is reproduced in full length. Refs, figs and tabs

Synthetic Strategies towards Fullerene-Rich Dendrimer Assemblies

Directory of Open Access Journals (Sweden)

Jean-François Nierengarten

2012-02-01

Full Text Available The sphere-shaped fullerene has attracted considerable interest not least due to the peculiar electronic properties of this carbon allotrope and the fascinating materials emanating from fullerene-derived structures. The rapid development and tremendous advances in organic chemistry allow nowadays the modification of C60 to a great extent by pure chemical means. It is therefore not surprising that the fullerene moiety has also been part of dendrimers. At the initial stage, fullerenes have been examined at the center of the dendritic structure mainly aimed at possible shielding effects as exerted by the dendritic environment and light-harvesting effects due to multiple chromophores located at the periphery of the dendrimer. In recent years, also many research efforts have been devoted towards fullerene-rich nanohybrids containing multiple C60 units in the branches and/or as surface functional groups. In this review, synthetic efforts towards the construction of dendritic fullerene-rich nanostructures have been compiled and will be summarized herein.

Darlington GS vacuum building - internal structures and foundation

International Nuclear Information System (INIS)

Huterer, J.; Brown, D.G.; Yanchula, S.

1985-01-01

This paper describes the evolution of the internal structure from initial concept to final design. Fundamental changes to the original configuration were precipitated by the action of large seismic forces acting on a top-heavy configuration. Prestressing was eliminated in deference to high humidity. Aspects of the elevated water tank's peripheral support beam are discussed vis-a-vis an adjacent slipforming operation, and practical construction limitations on steel placement. Also reviewed are the shortening of peripheral columns due to shrinkage and creep, and considerations of crack control for purposes of water-tightness. The authors justify the choice of stainless steel for fabrication of the siphon system's riser pipes. The foundation slab must resist the combined effects of vacuum pressure, hydrostatic uplift, and the seismic reactions of the internal structure and perimeter wall. The dependency of a key foundation component, the gallery roof slab, on the dome tendon layout is high-lighted; and aspects of its constructability are reviewed in light of congestion of vertical tendon anchorages, and of reinforcement. The design of the air-tight slab liner is reviewed, attention focusing on weld design under vacuum and accident temperature loads; on corrosion protection; and on the related construction access bulkhead - its ASME requirements and fabrication tolerances. (orig.)

Platelet-rich fibrin in the treatment of periodontal bone defects.

Science.gov (United States)

Ranganathan, Aravindhan T; Chandran, Chitraa R

2014-05-01

Periodontitis is characterized by the formation of true pockets, bone loss and attachment loss. Various techniques have been attempted in the past to truly regenerate the lost periodontal structures, albeit with variable outcome. In this evolution, the technique being tried out widely is the use of platelet rich concentrates, namely platelet-rich fibrin (PRF). In this report, we present a case of surgical treatment of osseous bone defects namely two walled crater and dehiscence treated in posterior teeth with autologously prepared platelet rich fibrin mixed with hydroxy apatite bone graft and PRF in the form of a membrane. Our results showed clinical improvements in all the clinical parameters postoperatively namely the pocket depth reduction and gain in attachment level and hence, PRF can be used alone or in combination with the bone graft to yield successful clinical results in treating periodontal osseous defects. Platelet-rich fibrin is an effective alternative to platelet-rich plasma (PRP) in reconstructing bone defects.

Internal structures of self-organized relaxed states and self-similar decay phase

International Nuclear Information System (INIS)

Kondoh, Yoshiomi

1992-03-01

A thought analysis on relaxation due to nonlinear processes is presented to lead to a set of general thoughts applicable to general nonlinear dynamical systems for finding out internal structures of the self-organized relaxed state without using 'invariant'. Three applications of the set of general thoughts to energy relaxations in resistive MHD plasmas, incompressible viscous fluids, and incompressible viscous MHD fluids are shown to lead to the internal structures of the self-organized relaxed states. It is shown that all of the relaxed states in these three dynamical systems are followed by self-similar decay phase without significant change of the spatial structure. The well known relaxed state of ∇ x B = ±λ B is shown to be derived generally in the low β plasma limit. (author)

A Novel Platelet Concentrate: Titanium-Prepared Platelet-Rich Fibrin

OpenAIRE

Mustafa Tunalı; Hakan Özdemir; Zafer Küçükodacı; Serhan Akman; Emre Yaprak; Hülya Toker; Erhan Fıratlı

2014-01-01

We developed a new product called titanium-prepared platelet-rich fibrin (T-PRF). The T-PRF method is based on the hypothesis that titanium may be more effective in activating platelets than the silica activators used with glass tubes in Chouckroun's leukocyte- and platelet-rich fibrin (L-PRF) method. In this study, we aimed to define the structural characteristics of T-PRF and compare it with L-PRF. Blood samples were collected from 10 healthy male volunteers. The blood samples were drawn us...

Correlation between reflectance and photoluminescent properties of al-rich ZnO nano-structures

Science.gov (United States)

Khan, Firoz; Baek, Seong-Ho; Ahmad, Nafis; Lee, Gun Hee; Seo, Tae Hoon; Suh, Eun-kyung; Kim, Jae Hyun

2015-05-01

Al rich zinc oxide nano-structured films were synthesized using spin coating sol-gel technique. The films were annealed in oxygen ambient in the temperature range of 200-700 °C. The structural, optical, and photoluminescence (PL) properties of the films were studied at various annealing temperatures using X-ray diffraction spectroscopy, field emission scanning electron microscopy, photoluminescence emission spectra measurement, and Raman and UV-Vis spectroscopy. The optical band gap was found to decrease with the increase of the annealing temperature following the Gauss Amp function due to the confinement of the exciton. The PL peak intensity in the near band region (INBE) was found to increase with the increase of the annealing temperature up to 600 °C, then to decrease fast to a lower value for the annealing temperature of 700 °C due to crystalline quality. The Raman peak of E2 (low) was red shifted from 118 cm-1 to 126 cm-1 with the increase of the annealing temperature. The intensity of the second order phonon (TA+LO) at 674 cm-1 was found to decrease with the increase of the annealing temperature. The normalized values of the reflectance and the PL intensity in the NBE region were highest for the annealing temperature of 600 °C. A special correlation was found between the reflectance at λ = 1000 nm and the normalized PL intensity in the green region due to scattering due to presence of grains.

Species richness of motile cryptofauna across a gradient of reef framework erosion

Science.gov (United States)

Enochs, I. C.; Manzello, D. P.

2012-09-01

Coral reef ecosystems contain exceptionally high concentrations of marine biodiversity, potentially encompassing millions of species. Similar to tropical rainforests and their insects, the majority of reef animal species are small and cryptic, living in the cracks and crevices of structural taxa (trees and corals). Although the cryptofauna make up the majority of a reef's metazoan biodiversity, we know little about their basic ecology. We sampled motile cryptofaunal communities from both live corals and dead carbonate reef framework across a gradient of increasing erosion on a reef in Pacific Panamá. A total of 289 Operational Taxonomic Units (OTUs) from six phyla were identified. We used species-accumulation models fitted to individual- and sample-based rarefaction curves, as well as seven nonparametric richness estimators to estimate species richness among the different framework types. All procedures predicted the same trends in species richness across the differing framework types. Estimated species richness was higher in dead framework (261-370 OTUs) than in live coral substrates (112-219 OTUs). Surprisingly, richness increased as framework structure was eroded: coral rubble contained the greatest number of species (227-320 OTUs) and the lowest estimated richness of 47-115 OTUs was found in the zone where the reef framework had the greatest vertical relief. This contradicts the paradigm that abundant live coral indicates the apex of reef diversity.

Frustration-induced internal stresses are responsible for quasilocalized modes in structural glasses

Science.gov (United States)

Lerner, Edan; Bouchbinder, Eran

2018-03-01

It has been recently shown [E. Lerner, G. Düring, and E. Bouchbinder, Phys. Rev. Lett. 117, 035501 (2016), 10.1103/PhysRevLett.117.035501] that the nonphononic vibrational modes of structural glasses at low frequencies ω are quasilocalized and follow a universal density of states D (ω ) ˜ω4 . Here we show that the gapless nature of the observed density of states depends on the existence of internal stresses that generically emerge in glasses due to frustration, thus elucidating a basic element underlying this universal behavior. Similarly to jammed particulate packings, low-frequency modes in structural glasses emerge from a balance between a local elasticity term and an internal stress term in the dynamical matrix, where the difference between them is orders of magnitude smaller than their typical magnitude. By artificially reducing the magnitude of internal stresses in a computer glass former in three dimensions, we show that a gap is formed in the density of states below which no vibrational modes exist, thus demonstrating the crucial importance of internal stresses. Finally, we show that while better annealing the glass upon cooling from the liquid state significantly reduces its internal stresses, the self-organizational processes during cooling render the gapless D (ω ) ˜ω4 density of state unaffected.

The structure and species richness of the diatom assemblages of the Western Carpathian spring fens along the gradient of mineral richness

Czech Academy of Sciences Publication Activity Database

Fránková, Markéta; Bojková, J.; Poulíčková, A.; Hájek, Michal

2009-01-01

Roč. 9, č. 2 (2009), s. 355-368 ISSN 1802-5439 Institutional research plan: CEZ:AV0Z60050516 Keywords : diatoms * Western Carpathians * poor-rich gradient Subject RIV: EF - Botanics Impact factor: 1.762, year: 2009

International trade shows: Structure, strategy and performance of exhibitors at individual booths vs. joint booths

DEFF Research Database (Denmark)

Hansen, Kåre

2000-01-01

This paper examines differences in exhibitors who participate at international trade shows at joint booths and those who participate at individual booths. The structure, strategy, and trade show performance of exhibitors at joint booths and those at individual booths are analysed. The analysis...... implications for exhibitors at interna-tional trade shows and export marketing programmes and other marketing programmes offering services to international trade show exhibitors....... of exhibitors at the international food shows SIAL (Paris) and ANUGA (Cologne) showed several significant differences with regard to structure and strategy. However, no significant differences in the performance assessments between the two partici-pation modes were found. The findings have important...

Enhancement of white light OLED efficiency by combining both internal and external light extraction structures

Science.gov (United States)

Kao, I.-Ling; Ku, Chun-Neng; Chen, Yi-Ping; Lin, Ding-Zheng

2012-09-01

We proposed an internal nanostructure with a high reflective index planarization layer to solve the optical loss due to the reflective index mismatch between ITO and glass substrate. In our experiments, we found the electrical property of OLED device was significantly influenced by the internal nanostructures without planarization layer. Moreover, the internal extraction structure (IES) is not necessarily beneficial for light extraction. Therefore, we proposed a new substrate combine both internal and external extraction structure (EES) to extract trapping light. We successfully developed a high refractive index (N 1.7) planarization material with flat surface (RMS roughness < 2 nm), and improved about 70% device efficiency compared to traditional glass substrate.

Production of recombinant disulfide-rich venom peptides for structural and functional analysis via expression in the periplasm of E. coli.

Directory of Open Access Journals (Sweden)

Julie K Klint

Full Text Available Disulfide-rich peptides are the dominant component of most animal venoms. These peptides have received much attention as leads for the development of novel therapeutic agents and bioinsecticides because they target a wide range of neuronal receptors and ion channels with a high degree of potency and selectivity. In addition, their rigid disulfide framework makes them particularly well suited for addressing the crucial issue of in vivo stability. Structural and functional characterization of these peptides necessitates the development of a robust, reliable expression system that maintains their native disulfide framework. The bacterium Escherichia coli has long been used for economical production of recombinant proteins. However, the expression of functional disulfide-rich proteins in the reducing environment of the E. coli cytoplasm presents a significant challenge. Thus, we present here an optimised protocol for the expression of disulfide-rich venom peptides in the periplasm of E. coli, which is where the endogenous machinery for production of disulfide-bonds is located. The parameters that have been investigated include choice of media, induction conditions, lysis methods, methods of fusion protein and peptide purification, and sample preparation for NMR studies. After each section a recommendation is made for conditions to use. We demonstrate the use of this method for the production of venom peptides ranging in size from 2 to 8 kDa and containing 2-6 disulfide bonds.

Reactor building with internal structure of which the movements are independent of those of the general raft and process for building these internal structures

International Nuclear Information System (INIS)

Hista, J.C.

1982-01-01

This reactor building includes a containment enclosure for the internal structures composed of a slab wedged on its periphery against the containment enclosure gusset and resting on the general raft by means of a peripheral bearing ring, a compressible layer being provided between the general raft and the slab [fr

Minimally Invasive Treatment with Platelet Rich Plasma in Patients with Knee Osteoarthritis

Directory of Open Access Journals (Sweden)

Albu Daniel–Emil

2016-09-01

Full Text Available Background: The main target of the structural damage in osteoarthritisis the hyaline cartilage. New options such as PRP (platelet rich plasma may cause structural improvement of the cartilage.

Guangxi crustal structural evolution and the formation and distribution regularities of U-rich strata

International Nuclear Information System (INIS)

Kang Zili.

1989-01-01

Based on summing up Guangxi geotectonic features and evolutionary regularities, this paper discusses the occurrence features, formation conditions and time-space distribution regularities of various U-rich strata during the development of geosyncline, platform and diwa stages, Especially, during diwa stage all those U-rich strata might be reworked to a certain degree and resulted in the mobilization of uranium, then enriching to form polygenetic composite uranium ore deposits with stratabound features. This study will be helpful for prospecting in the region

CHANGES IN STRUCTURE OF ROMANIA'S INTERNATIONAL TRADE

Directory of Open Access Journals (Sweden)

CECILIA IRINA RABONTU

2014-05-01

Full Text Available Evolution of structural changes in Romanian trade is somewhat interesting if you look at it from the perspective of mutations that occurred in the categories of goods and services subject to international trade. After the Revolution of 1989, the Romanian economy has gone through dramatic changes that had determinate a total reconfiguration of foreign trade. At the same time, the economic instability has had further repercussions on the Romanian economy manifested through higher prices, reduced wages or earnings, reduced employment and rising unemployment, increasing interest rates on loans due to the devaluation of the national currency, increase value-added tax, consumption reduction etc. We proposed in this paper an analyze for a significant period of time evolution of international trade in goods and services of Romania in order to establish the main categories of goods traded but Romania's main trading partners, too. In order to achieve the central goal of this paper we will use statistical data found in the databases provided by the WTO, Eurostat and the National Statistical Institutes and statistical methods to support our initiative.

Age-associated changes in rich-club organisation in autistic and neurotypical human brains.

Science.gov (United States)

Watanabe, Takamitsu; Rees, Geraint

2015-11-05

Macroscopic structural networks in the human brain have a rich-club architecture comprising both highly inter-connected central regions and sparsely connected peripheral regions. Recent studies show that disruption of this functionally efficient organisation is associated with several psychiatric disorders. However, despite increasing attention to this network property, whether age-associated changes in rich-club organisation occur during human adolescence remains unclear. Here, analysing a publicly shared diffusion tensor imaging dataset, we found that, during adolescence, brains of typically developing (TD) individuals showed increases in rich-club organisation and inferred network functionality, whereas individuals with autism spectrum disorders (ASD) did not. These differences between TD and ASD groups were statistically significant for both structural and functional properties. Moreover, this typical age-related changes in rich-club organisation were characterised by progressive involvement of the right anterior insula. In contrast, in ASD individuals, did not show typical increases in grey matter volume, and this relative anatomical immaturity was correlated with the severity of ASD social symptoms. These results provide evidence that rich-club architecture is one of the bases of functionally efficient brain networks underpinning complex cognitive functions in adult human brains. Furthermore, our findings suggest that immature rich-club organisation might be associated with some neurodevelopmental disorders.

Generic Structure of Discussion Sections in ESP Research Articles across International and Iranian Journals

Directory of Open Access Journals (Sweden)

Masoud Khalili Sabet

2015-04-01

Full Text Available Reviewing literature reveals that identifying generic structure of research articles (RAs in different fields of study, especially ESP, has received much attention. The major purpose behind such trends of research has been raising researchers' awareness of the common conventions in writing RAs. Along with this universal trend, a lot of genre studies have been done in Iranian context; however, it seems that ESP RAs have not been paid due attention yet. Hence this study aimed at investigating the generic structure of ESP RAs in international and Iranian journals. Applying Kanoksilapatham's (2007 model to the compiled corpus, it was found that contextualizing the study (Move 1 and consolidating results (Move 2 were the obligatory moves in Discussion section of ESP RAs across international and Iranian journals. Evaluation of the findings was a new step found in international Discussion sections but absent in Iranian ones. Related discussion of these findings prepares the researchers for publishing in international and Iranian ESP journals. Keywords: ESP, Discussion section, Move, Step, Author presence, Generic structure

The Cambridge Companion to International Law

Directory of Open Access Journals (Sweden)

Achmad Gusman Siswandi

2014-08-01

Full Text Available ABSTRAK This book provides a thorough introduction to international law in a way that is rather unique compared to similar references. The subject matteris divided in a more concise way, while still giving rich perspective as it covers not only theories but also case studies and practices. This book consists of four parts, namely: the contexts of international law; international law and the state; techniques and arenas; and projects of international law.

Design and analysis of CANDU NPP internal structures for Japanese conditions

International Nuclear Information System (INIS)

Aziz, T.S.; Murakami, H.

1991-01-01

The design and analysis approach for the CANDU 6 Internal Concrete Structure (ICS) for Japanese seismic conditions is described. The approach consists of a seismic analysis to determine the design level accelerations; followed by a detailed finite element analysis to determine the section forces for each shell element. The extent of the design modifications for the original structure to meet the Japanese design conditions is given. (author)

46 CFR 71.50-3 - Drydock examination, internal structural examination, underwater survey, and alternate hull exam...

Science.gov (United States)

2010-10-01

..., underwater survey, and alternate hull exam intervals. 71.50-3 Section 71.50-3 Shipping COAST GUARD...-3 Drydock examination, internal structural examination, underwater survey, and alternate hull exam... wooden hulls must undergo two drydock and two internal structural examinations within any five year...

Dynamic partitioning of a glycosyl-phosphatidylinositol-anchored protein in glycosphingolipid-rich microdomains imaged by single-quantum dot tracking.

Science.gov (United States)

Pinaud, Fabien; Michalet, Xavier; Iyer, Gopal; Margeat, Emmanuel; Moore, Hsiao-Ping; Weiss, Shimon

2009-06-01

Recent experimental developments have led to a revision of the classical fluid mosaic model proposed by Singer and Nicholson more than 35 years ago. In particular, it is now well established that lipids and proteins diffuse heterogeneously in cell plasma membranes. Their complex motion patterns reflect the dynamic structure and composition of the membrane itself, as well as the presence of the underlying cytoskeleton scaffold and that of the extracellular matrix. How the structural organization of plasma membranes influences the diffusion of individual proteins remains a challenging, yet central, question for cell signaling and its regulation. Here we have developed a raft-associated glycosyl-phosphatidyl-inositol-anchored avidin test probe (Av-GPI), whose diffusion patterns indirectly report on the structure and dynamics of putative raft microdomains in the membrane of HeLa cells. Labeling with quantum dots (qdots) allowed high-resolution and long-term tracking of individual Av-GPI and the classification of their various diffusive behaviors. Using dual-color total internal reflection fluorescence (TIRF) microscopy, we studied the correlation between the diffusion of individual Av-GPI and the location of glycosphingolipid GM1-rich microdomains and caveolae. We show that Av-GPI exhibit a fast and a slow diffusion regime in different membrane regions, and that slowing down of their diffusion is correlated with entry in GM1-rich microdomains located in close proximity to, but distinct, from caveolae. We further show that Av-GPI dynamically partition in and out of these microdomains in a cholesterol-dependent manner. Our results provide direct evidence that cholesterol-/sphingolipid-rich microdomains can compartmentalize the diffusion of GPI-anchored proteins in living cells and that the dynamic partitioning raft model appropriately describes the diffusive behavior of some raft-associated proteins across the plasma membrane.

Value-Added Products from FGD Sulfite-Rich Scrubber Materials

Energy Technology Data Exchange (ETDEWEB)

Vivak Malhotra

2010-01-31

According to the American Coal Ash Association, about 29.25 million tons of flue gas desulfurization (FGD) byproducts were produced in the USA in 2003. Out of 29.25 million tons, 17.35 million tons were sulfite-rich scrubber materials. At present, unlike its cousin FGD gypsum, the prospect for effective utilization of sulfite-rich scrubber materials is not bright. In fact, almost 16.9 million tons are leftover every year. In our pursuit to mitigate the liability of sulfite-rich FGD scrubber materials' disposal, we are attempting to develop value-added products that can commercially compete. More specifically, for this Innovative Concept Phase I project, we have the following objectives: to characterize the sulfite-rich scrubber material for toxic metals; to optimize the co-blending and processing of scrubber material and natural byproducts; to formulate and develop structural composites from sulfite-rich scrubber material; and to evaluate the composites' mechanical properties and compare them with current products on the market. After successfully demonstrating the viability of our research, a more comprehensive approach will be proposed to take these value-added materials to fruition.

How rich is Australia's minerals endowment and is it adequate to sustain a major role in meeting international demand?

Science.gov (United States)

Lambert, I. B.

2012-04-01

Dr Ian Lambert, Geoscience Australia and Secretary General 34th International Geological Congress Australia has comparative advantages in production of mineral commodities compared to most other countries. These stem from its rich and diverse mineral endowment; availability of regional scale (pre-competitive) geoscience information to lower the risks of exploration; advances in exploration, mining and processing technologies; skilled work force; generally benign physical conditions; and low population density. Building on these strengths, Australia is a major producer and exporter of a wide range of mineral and energy commodities to global markets. Given that demand for most major commodities is likely to continue, and that there will be growing markets for some other commodities, Australia needs to have a strategic view of what is likely to be available for mining. Further, Australia (and the world) needs to be attuned to issues that need to be faced in meeting international demand for commodities in the long term. This presentation outlines how Australia's national minerals inventory is compiled. It discusses trends for Australia's identified mineral resources for major commodities, and how these compare with other major mining nations. It then considers some significant issues in relation to sustaining a strong mining sector - in the medium to long term this requires a strategic approach to achieve goals such as more effective/lower risk exploration particularly in greenfields regions; well-Informed decisions on mining proposals; ongoing significant improvements in efficiencies of energy, water and land use.

How countries become rich and reduce poverty

DEFF Research Database (Denmark)

Whitfield, Lindsay

2012-01-01

For the sake of less developed countries, it is time to adjust the discussion of international development assistance on poverty reduction. This article attempts to do so by reviewing new and old literature explaining why some countries are rich and others are poor. History has repeatedly shown...... that building up capabilities in manufacturing and improving the productivity of agriculture are the keys to wealth creation and long-term sustained poverty reduction. Furthermore, industrialisation and increased agricultural productivity are interdependent processes. Discussion about ending world poverty needs...

Structural policy in the context of international competition aggravation

Directory of Open Access Journals (Sweden)

Volodymyr Bodrov

2014-09-01

Full Text Available This article researches the essence and peculiarities of the structural policy, performs classification of its models and determines possibilities of their use in the context of increasing international competition. It discovers the main components of the economic structure and trends of the state policy regarding their modernization. Measures on improvement of state regulation instruments are offered, factors of influence upon improvement of the Ukrainian economy structure are analyzed and priority goals are systematized which require urgent implementation in the terms of competitive struggle aggravation at the global markets. The article also researches the matter of importance of performing a complex of state functional and selective measures in the form of matrix policy for the purpose of protecting national interests of the country in the context of global challenges

Internal structure of an ex-vessel corium debris bed during severe accidents of LWRs

Energy Technology Data Exchange (ETDEWEB)

Kim, Eunho; Park, Jin Ho; Moriyama, Kiyofumi; Park, Hyun Sun [POSTECH, Daejeon (Korea, Republic of)

2015-10-15

In the aspect of the coolability assessment the configuration of the debris bed, including internal and external characteristics, has significant importance as boundary conditions for simulations, however, relatively little investigation of the sedimentation process. For the development of a debris bed, recently there have been several studies that focused on thermal characteristics of corium particles. Yakush et al. performed simulation studies and showed that two phase natural convection affects the particle settling trajectory and changes the final arrival location of particles to result more flattened bed. Those simulation results have been supported by the experimental studies of Kim et al. using simulant particles and air bubble injection. For the internal structure of a debris bed, there have been several simulation and experimental studies, which investigated the effect of internal structure on debris bed coolability. Magallon has reported the particle size distribution at three elevations of the debris bed of FARO L-31 case, where the mean particle size was bigger for the lower elevation. However, there is a lack of detailed information on the characteristics of the debris bed, including the local structure and porosity. In this study, we investigated the internal structure of the debris bed using a mixture of stainless steel particles and air bubble injection. Local particle sedimentation quantity, particle size distribution change in radial direction and axial direction, and bed porosity was measured to investigate a relationship between the internal structure and the accident condition. An experimental investigation was carried out for the internal structure of ex-vessel corium debris bed in the flooded cavity during sever accident. Moderate corium discharge in high flooding level was assumed for full fragmentation of melt jet. The test particle mixture was prepared by following an empirical correlation, which reflects the particle size distribution of

Internal structure of an ex-vessel corium debris bed during severe accidents of LWRs

International Nuclear Information System (INIS)

Kim, Eunho; Park, Jin Ho; Moriyama, Kiyofumi; Park, Hyun Sun

2015-01-01

In the aspect of the coolability assessment the configuration of the debris bed, including internal and external characteristics, has significant importance as boundary conditions for simulations, however, relatively little investigation of the sedimentation process. For the development of a debris bed, recently there have been several studies that focused on thermal characteristics of corium particles. Yakush et al. performed simulation studies and showed that two phase natural convection affects the particle settling trajectory and changes the final arrival location of particles to result more flattened bed. Those simulation results have been supported by the experimental studies of Kim et al. using simulant particles and air bubble injection. For the internal structure of a debris bed, there have been several simulation and experimental studies, which investigated the effect of internal structure on debris bed coolability. Magallon has reported the particle size distribution at three elevations of the debris bed of FARO L-31 case, where the mean particle size was bigger for the lower elevation. However, there is a lack of detailed information on the characteristics of the debris bed, including the local structure and porosity. In this study, we investigated the internal structure of the debris bed using a mixture of stainless steel particles and air bubble injection. Local particle sedimentation quantity, particle size distribution change in radial direction and axial direction, and bed porosity was measured to investigate a relationship between the internal structure and the accident condition. An experimental investigation was carried out for the internal structure of ex-vessel corium debris bed in the flooded cavity during sever accident. Moderate corium discharge in high flooding level was assumed for full fragmentation of melt jet. The test particle mixture was prepared by following an empirical correlation, which reflects the particle size distribution of

On the internal consistency of the term structure of forecasts of housing starts

DEFF Research Database (Denmark)

Pierdzioch, C.; Rulke, J. C.; Stadtmann, G.

2013-01-01

We use the term structure of forecasts of housing starts to test for rationality of forecasts. Our test is based on the idea that short-term and long-term forecasts should be internally consistent. We test the internal consistency of forecasts using data for Australia, Canada, Japan and the United...

Engineering the internal structure of magnetic silica nanoparticles by thermal control

KAUST Repository

Song, Hyon Min

2014-09-30

Calcination of hydrated iron salts in the pores of both spherical and rod-shaped mesoporous silica nanoparticles (NPs) changes the internal structure from an ordered 2D hexagonal structure into a smaller number of large voids in the particles with sizes ranging from large hollow cores down to ten nanometer voids. The voids only form when the heating rate is rapid at a rate of 30 °C min-1. The sizes of the voids are controlled reproducibly by the final calcination temperature; as the temperature is decreased the number of voids decreases as their size increases. The phase of the iron oxide NPs is α-Fe2O3 when annealed at 500 °C, and Fe3O4 when annealed at lower temperatures. The water molecules in the hydrated iron (III) chloride precursor salts appear to play important roles by hydrolyzing Si-O-Si bonding, and the resulting silanol is mobile enough to affect the reconstruction into the framed hollow structures at high temperature. Along with hexahydrates, trivalent Fe3+ ions are assumed to contribute to the structure disruption of mesoporous silica by replacing tetrahedral Si4+ ions and making Fe-O-Si bonding. Volume fraction tomography images generated from transmission electron microscopy (TEM) images enable precise visualization of the structures. These results provide a controllable method of engineering the internal shapes in silica matrices containing superparamagnetic NPs.

Engineering the internal structure of magnetic silica nanoparticles by thermal control

KAUST Repository

Song, Hyon Min; Zink, Jeffrey I.; Khashab, Niveen M.

2014-01-01

Calcination of hydrated iron salts in the pores of both spherical and rod-shaped mesoporous silica nanoparticles (NPs) changes the internal structure from an ordered 2D hexagonal structure into a smaller number of large voids in the particles with sizes ranging from large hollow cores down to ten nanometer voids. The voids only form when the heating rate is rapid at a rate of 30 °C min-1. The sizes of the voids are controlled reproducibly by the final calcination temperature; as the temperature is decreased the number of voids decreases as their size increases. The phase of the iron oxide NPs is α-Fe2O3 when annealed at 500 °C, and Fe3O4 when annealed at lower temperatures. The water molecules in the hydrated iron (III) chloride precursor salts appear to play important roles by hydrolyzing Si-O-Si bonding, and the resulting silanol is mobile enough to affect the reconstruction into the framed hollow structures at high temperature. Along with hexahydrates, trivalent Fe3+ ions are assumed to contribute to the structure disruption of mesoporous silica by replacing tetrahedral Si4+ ions and making Fe-O-Si bonding. Volume fraction tomography images generated from transmission electron microscopy (TEM) images enable precise visualization of the structures. These results provide a controllable method of engineering the internal shapes in silica matrices containing superparamagnetic NPs.

Passively Aerated Composting of Straw-Rich Pig Manure : Effect of Compost Bed Porosity

NARCIS (Netherlands)

Veeken, A.H.M.; Wilde, de V.; Hamelers, H.V.M.

2002-01-01

Straw-rich manure from organic pig farming systems can be composted in passively aerated systems as the high application of straw results in a compost bed with good structure and porosity. The passively aerated composting process was simulated in one-dimensional reactors of 2 m3 for straw-rich

Institutional Structure and International Competitiveness Relationship in Developed Countries

Directory of Open Access Journals (Sweden)

Aynur Yıldırım

2016-06-01

Full Text Available This study analyzes the effects of institutional structure on the international competitiveness of developed countries econometrically by employing a “Panel Data Analysis” with a sample of 21 developed countries and 23 institutional variables for the period 2000-2011. The results of the analysis indicate that while judicial independence, protection of intellectual property rights, integrity of the juridical system, marginal tax, political freedoms, black market exchange rate, restrictions on foreign investment, private sector’s share in the banking system, hiring-minimum wage, and hiring-dismissal have a positive effect; the nature of legal arrangements, government spending, transfers and subsidies, civil liberties, tariffs, regulations regarding trade barriers, collective bargaining, and military tutelage have a negative effect on the international competitiveness of developed countries.

Disentangling the Role of Climate, Topography and Vegetation in Species Richness Gradients.

Directory of Open Access Journals (Sweden)

Mario R Moura

Full Text Available Environmental gradients (EG related to climate, topography and vegetation are among the most important drivers of broad scale patterns of species richness. However, these different EG do not necessarily drive species richness in similar ways, potentially presenting synergistic associations when driving species richness. Understanding the synergism among EG allows us to address key questions arising from the effects of global climate and land use changes on biodiversity. Herein, we use variation partitioning (also know as commonality analysis to disentangle unique and shared contributions of different EG in explaining species richness of Neotropical vertebrates. We use three broad sets of predictors to represent the environmental variability in (i climate (annual mean temperature, temperature annual range, annual precipitation and precipitation range, (ii topography (mean elevation, range and coefficient of variation of elevation, and (iii vegetation (land cover diversity, standard deviation and range of forest canopy height. The shared contribution between two types of EG is used to quantify synergistic processes operating among EG, offering new perspectives on the causal relationships driving species richness. To account for spatially structured processes, we use Spatial EigenVector Mapping models. We perform analyses across groups with distinct dispersal abilities (amphibians, non-volant mammals, bats and birds and discuss the influence of vagility on the partitioning results. Our findings indicate that broad scale patterns of vertebrate richness are mainly affected by the synergism between climate and vegetation, followed by the unique contribution of climate. Climatic factors were relatively more important in explaining species richness of good dispersers. Most of the variation in vegetation that explains vertebrate richness is climatically structured, supporting the productivity hypothesis. Further, the weak synergism between topography and

Design and R&D of RICH detectors for EIC experiments

Science.gov (United States)

Del Dotto, A.; Wong, C.-P.; Allison, L.; Awadi, M.; Azmoun, B.; Barbosa, F.; Brooks, W.; Cao, T.; Chiu, M.; Cisbani, E.; Contalbrigo, M.; Datta, A.; Demarteau, M.; Durham, J. M.; Dzhygadlo, R.; Fields, D.; Furletova, Y.; Gleason, C.; Grosse-Perdekamp, M.; Harris, J.; He, X.; van Hecke, H.; Horn, T.; Huang, J.; Hyde, C.; Ilieva, Y.; Kalicy, G.; Kimball, M.; Kistenev, E.; Kulinich, Y.; Liu, M.; Majka, R.; McKisson, J.; Mendez, R.; Nadel-Turonski, P.; Park, K.; Peters, K.; Rao, T.; Pisani, R.; Qiang, Y.; Rescia, S.; Rossi, P.; Sarsour, M.; Schwarz, C.; Schwiening, J.; da Silva, C. L.; Smirnov, N.; Stein, H.; Stevens, J.; Sukhanov, A.; Syed, S.; Tate, A.; Toh, J.; Towell, C.; Towell, R.; Tsang, T.; Wagner, R.; Wang, J.; Woody, C.; Xi, W.; Xie, J.; Zhao, Z. W.; Zihlmann, B.; Zorn, C.

2017-12-01

An Electron-Ion Collider (EIC) has been proposed to further explore the strong force and QCD, focusing on the structure and the interaction of gluon-dominated matter. A generic detector R&D program (EIC PID consortium) for the particle identification in EIC experiments was formed to explore technologically advanced solutions in this scope. In this context two Ring Imaging Cherenkov (RICH) counters have been proposed: a modular RICH detector which consists of an aerogel radiator, a Fresnel lens, a mirrored box, and pixelated photon sensor; a dual-radiator RICH, consisting of an aerogel radiator and C2F6 gas in a mirror-focused configuration. We present the simulations of the two detectors and their estimated performance.

Data envelopment analysis a handbook of modeling internal structure and network

CERN Document Server

Cook, Wade D

2014-01-01

This comprehensive handbook on state-of-the-art topics in DEA modeling of internal structures and networks presents work by leading researchers who share their results on subjects including additive efficiency decomposition and slacks-based network DEA.

Species Richness Responses to Structural or Compositional Habitat Diversity between and within Grassland Patches: A Multi-Taxon Approach

Science.gov (United States)

Lengyel, Szabolcs; Déri, Eszter; Magura, Tibor

2016-01-01

Habitat diversity (spatial heterogeneity within and between habitat patches in a landscape, HD) is often invoked as a driver of species diversity at small spatial scales. However, the effect of HD on species richness (SR) of multiple taxa is not well understood. We quantified HD and SR in a wet-dry gradient of open grassland habitats in Hortobágy National Park (E-Hungary) and tested the effect of compositional and structural factors of HD on SR of flowering plants, orthopterans, true bugs, spiders, ground beetles and birds. Our dataset on 434 grassland species (170 plants, 264 animals) showed that the wet-dry gradient (compositional HD at the between-patch scale) was primarily related to SR in orthopterans, ground-dwelling arthropods, and all animals combined. The patchiness, or plant association richness, of the vegetation (compositional HD at the within-patch scale) was related to SR of vegetation-dwelling arthropods, whereas vegetation height (structural HD at the within-patch scale) was related to SR of ground-dwelling arthropods and birds. Patch area was related to SR only in birds, whereas management (grazing, mowing, none) was related to SR of plants and true bugs. All relationships between HD and SR were positive, indicating increasing SR with increasing HD. However, total SR was not related to HD because different taxa showed similar positive responses to different HD variables. Our findings, therefore, show that even though HD positively influences SR in a wide range of grassland taxa, each taxon responds to different compositional or structural measures of HD, resulting in the lack of a consistent relationship between HD and SR when taxon responses are pooled. The idiosyncratic responses shown here exemplify the difficulties in detecting general HD-SR relationships over multiple taxa. Our results also suggest that management and restoration aimed specifically to sustain or increase the diversity of habitats are required to conserve biodiversity in

Species Richness Responses to Structural or Compositional Habitat Diversity between and within Grassland Patches: A Multi-Taxon Approach.

Directory of Open Access Journals (Sweden)

Szabolcs Lengyel

Full Text Available Habitat diversity (spatial heterogeneity within and between habitat patches in a landscape, HD is often invoked as a driver of species diversity at small spatial scales. However, the effect of HD on species richness (SR of multiple taxa is not well understood. We quantified HD and SR in a wet-dry gradient of open grassland habitats in Hortobágy National Park (E-Hungary and tested the effect of compositional and structural factors of HD on SR of flowering plants, orthopterans, true bugs, spiders, ground beetles and birds. Our dataset on 434 grassland species (170 plants, 264 animals showed that the wet-dry gradient (compositional HD at the between-patch scale was primarily related to SR in orthopterans, ground-dwelling arthropods, and all animals combined. The patchiness, or plant association richness, of the vegetation (compositional HD at the within-patch scale was related to SR of vegetation-dwelling arthropods, whereas vegetation height (structural HD at the within-patch scale was related to SR of ground-dwelling arthropods and birds. Patch area was related to SR only in birds, whereas management (grazing, mowing, none was related to SR of plants and true bugs. All relationships between HD and SR were positive, indicating increasing SR with increasing HD. However, total SR was not related to HD because different taxa showed similar positive responses to different HD variables. Our findings, therefore, show that even though HD positively influences SR in a wide range of grassland taxa, each taxon responds to different compositional or structural measures of HD, resulting in the lack of a consistent relationship between HD and SR when taxon responses are pooled. The idiosyncratic responses shown here exemplify the difficulties in detecting general HD-SR relationships over multiple taxa. Our results also suggest that management and restoration aimed specifically to sustain or increase the diversity of habitats are required to conserve

Jacking mechanism for upper internals structure of a liquid metal nuclear reactor

International Nuclear Information System (INIS)

Gillett, J.E.; Wineman, A.L.

1984-01-01

A jacking mechanism is described for raising the upper internals structure of a liquid metal nuclear reactor which jacking mechanism uses a system of gears and drive shafts to transmit force from a single motor to four mechanically synchronized ball jacks to raise and lower support columns which support the upper internals structure. The support columns have a pin structure which rides up and down in a slot in a housing fixed to the reactor head. The pin has two locking plates which can be rotated around the pin to bring bolt holes through the locking plates into alignment with a set of bolt holes in the housing, there being a set of such housing bolt holes corresponding to both a raised and a lowered position of the support column. When the locking plate is so aligned, a surface of the locking plate mates with a surface in the housing such that the support column is then supported by the locking plate and not by the ball jacks. Since the locking plates are to be installed and bolted to the housing during periods of reactor operation, the ball jacks need not be sized to react the large forces which occur or potentially could occur on the upper internals structure of the reactor during operation. The locking plates react these loads. The ball jacks, used only during refueling, can be smaller, which enable conventionally available equipment to fulfill the precision requirements for the task within available space

VET Workers' Problem-Solving Skills in Technology-Rich Environments: European Approach

Science.gov (United States)

Hämäläinen, Raija; Cincinnato, Sebastiano; Malin, Antero; De Wever, Bram

2014-01-01

The European workplace is challenging VET adults' problem-solving skills in technology-rich environments (TREs). So far, no international large-scale assessment data has been available for VET. The PIAAC data comprise the most comprehensive source of information on adults' skills to date. The present study (N = 50 369) focuses on gaining insight…

Internal wave structures in abyssal cataract flows

Science.gov (United States)

Makarenko, Nikolay; Liapidevskii, Valery; Morozov, Eugene; Tarakanov, Roman

2014-05-01

We discuss some theoretical approaches, experimental results and field data concerning wave phenomena in ocean near-bottom stratified flows. Such strong flows of cold water form everywhere in the Atlantic abyssal channels, and these currents play significant role in the global water exchange. Most interesting wave structures arise in a powerful cataract flows near orographic obstacles which disturb gravity currents by forced lee waves, attached hydraulic jumps, mixing layers etc. All these effects were observed by the authors in the Romanche and Chain fracture zones of Atlantic Ocean during recent cruises of the R/V Akademik Ioffe and R/V Akademik Sergei Vavilov (Morozov et al., Dokl. Earth Sci., 2012, 446(2)). In a general way, deep-water cataract flows down the slope are similar to the stratified flows examined in laboratory experiments. Strong mixing in the sill region leads to the splitting of the gravity current into the layers having the fluids with different densities. Another peculiarity is the presence of critical layers in shear flows sustained over the sill. In the case under consideration, this critical level separates the flow of near-bottom cold water from opposite overflow. In accordance with known theoretical models and laboratory measurements, the critical layer can absorb and reflect internal waves generated by the topography, so the upward propagation of these perturbations is blocked from above. High velocity gradients were registered downstream in the vicinity of cataract and it indicates the existence of developed wave structures beyond the sill formed by intense internal waves. This work was supported by RFBR (grants No 12-01-00671-a, 12-08-10001-k and 13-08-10001-k).

The Persistence of Structural Inequality?: A Network Analysis of International Trade, 1965-2000

Science.gov (United States)

Mahutga, Matthew C.

2006-01-01

This article reports results from a network analysis of international trade from 1965 through 2000. It addresses the impact of changes associated with globalization and the "new international division of labor" (NIDL) on structural inequality in the world economy. To assess this impact, I ask three specific questions. (1) Do patterns of…

Effect of the kind of alkaline and rare earth ions on the structure of a glass rich in earth; Effet de la nature des ions alcalins et alcalino-terreux sur la structure d un verre riche en terre

Energy Technology Data Exchange (ETDEWEB)

Quintas, Arnaud; Caurant, Daniel; Majerus, Odile [Laboratoire de Chimie Appliquee de l Etat Solide, UMR 7574, ENSCP, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05, (France); Lenoir, Marion; Dussossoy, Jean-Luc [Commissariat a l Energie Atomique, Centre d Etudes de la Vallee du Rhone, DIEC/SCDV/LEBM, 30207 Bagnols-sur-Ceze, (France); Charpentier, Thibault [Service de Chimie Moleculaire, DSM/DRECAM/CEA Saclay, 91191 Gif-sur-Yvette Cedex, (France); Neuville, Daniel R. [Laboratoire de Physique des Mineraux et des Magmas, UMR 7047-CNRS-IPGP, Universite Pierre et Marie Curie, 4 place Jussieu, 75252 Paris Cedex 05, (France); Gervais, C. [Laboratoire de Chimie de la matiere condensee, UMR7574, Universite Pierre et Marie Curie, 4 place Jussieu, F-75252 Paris Cedex 05, (France)

2006-07-01

In the framework of a structural study of a nuclear wastes containment glass of type alumino borosilicate and rich in rare earths, the influence of the kind of alkaline or rare earth ions is analyzed. For that, two glasses series have been prepared in which the Na{sup +} ion (respectively Ca{sup 2+} ions) present in the standard composition is totally substituted by another alkaline ion Li{sup +}, K{sup +}, Rb{sup +} or Cs{sup +} (respectively another rare earth ion Mg{sup 2+}, Sr{sup 2+} or Ba{sup 2+}). These glasses, analyzed by optical absorption, Raman and {sup 27}Al or {sup 11}B NMR spectroscopies have revealed the strong impact of the kind of the modifying ion as well as the structure of the vitreous lattice (variation of the ratio BO{sub 3}/BO{sub 4} and local variations of the polymerization degree) than the local surroundings of the rare earth (decrease of the covalency degree of the bond Nd-O with the increase of the field force of the modifying ion). (O.M.)

Reduced thermal quenching in indium-rich self-organized InGaN/GaN quantum dots

KAUST Repository

Elafandy, Rami T.

2012-01-01

Differences in optical and structural properties of indium rich (27), indium gallium nitride (InGaN) self-organized quantum dots (QDs), with red wavelength emission, and the two dimensional underlying wetting layer (WL) are investigated. Temperature dependent micro-photoluminescence (?PL) reveals a decrease in thermal quenching of the QDs integrated intensity compared to that of the WL. This difference in behaviour is due to the 3-D localization of carriers within the QDs preventing them from thermalization to nearby traps causing an increase in the internal quantum efficiency of the device. Excitation power dependent ?PL shows a slower increase of the QDs PL signal compared to the WL PL which is believed to be due to the QDs saturation. © 2012 American Institute of Physics.

Coordination of the international network of nuclear structure and decay data evaluators

International Nuclear Information System (INIS)

Lorenz, A.

1984-09-01

This meeting of the International NSDD (Nuclear Structure and Decay Data) Network dealt with problems related to both the coordination of the NSDD network of centres and groups and to physics questions related to the evaluation of NSDD. The status of the mass-chain and nuclear structure data is reviewed and the planned activities are presented

Characterization of Slosh Damping for Ortho-Grid and Iso-Grid Internal Tank Structures

Science.gov (United States)

Westra, Douglas G.; Sansone, Marco D.; Eberhart, Chad J.; West, Jeffrey S.

2016-01-01

Grid stiffened tank structures such as Ortho-Grid and Iso-Grid are widely used in cryogenic tanks for providing stiffening to the tank while reducing mass, compared to tank walls of constant cross-section. If the structure is internal to the tank, it will positively affect the fluid dynamic behavior of the liquid propellant, in regard to fluid slosh damping. As NASA and commercial companies endeavor to explore the solar system, vehicles will by necessity become more mass efficient, and design margin will be reduced where possible. Therefore, if the damping characteristics of the Ortho-Grid and Iso-Grid structure is understood, their positive damping effect can be taken into account in the systems design process. Historically, damping by internal structures has been characterized by rules of thumb and for Ortho-Grid, empirical design tools intended for slosh baffles of much larger cross-section have been used. There is little or no information available to characterize the slosh behavior of Iso-Grid internal structure. Therefore, to take advantage of these structures for their positive damping effects, there is much need for obtaining additional data and tools to characterize them. Recently, the NASA Marshall Space Flight Center conducted both sub-scale testing and computational fluid dynamics (CFD) simulations of slosh damping for Ortho-Grid and Iso-Grid tanks for cylindrical tanks containing water. Enhanced grid meshing techniques were applied to the geometrically detailed and complex Ortho-Grid and Iso-Grid structures. The Loci-STREAM CFD program with the Volume of Fluid Method module for tracking and locating the water-air fluid interface was used to conduct the simulations. The CFD simulations were validated with the test data and new empirical models for predicting damping and frequency of Ortho-Grid and Iso-Grid structures were generated.

RCWA and FDTD modeling of light emission from internally structured OLEDs.

Science.gov (United States)

Callens, Michiel Koen; Marsman, Herman; Penninck, Lieven; Peeters, Patrick; de Groot, Harry; ter Meulen, Jan Matthijs; Neyts, Kristiaan

2014-05-05

We report on the fabrication and simulation of a green OLED with an Internal Light Extraction (ILE) layer. The optical behavior of these devices is simulated using both Rigorous Coupled Wave Analysis (RCWA) and Finite Difference Time-Domain (FDTD) methods. Results obtained using these two different techniques show excellent agreement and predict the experimental results with good precision. By verifying the validity of both simulation methods on the internal light extraction structure we pave the way to optimization of ILE layers using either of these methods.

Internal structure analysis of particle-double network gels used in a gel organ replica

Science.gov (United States)

Abe, Mei; Arai, Masanori; Saito, Azusa; Sakai, Kazuyuki; Kawakami, Masaru; Furukawa, Hidemitsu

2016-04-01

In recent years, the fabrication of patient organ replicas using 3D printers has been attracting a great deal of attention in medical fields. However, the cost of these organ replicas is very high as it is necessary to employ very expensive 3D printers and printing materials. Here we present a new gel organ replica, of human kidney, fabricated with a conventional molding technique, using a particle-double network hydrogel (P-DN gel). The replica is transparent and has the feel of a real kidney. It is expected that gel organ replicas produced this way will be a useful tool for the education of trainee surgeons and clinical ultrasonography technologists. In addition to developing a gel organ replica, the internal structure of the P-DN gel used is also discussed. Because the P-DN gel has a complex structure comprised of two different types of network, it has not been possible to investigate them internally in detail. Gels have an inhomogeneous network structure. If it is able to get a more uniform structure, it is considered that this would lead to higher strength in the gel. In the present study we investigate the structure of P-DN gel, using the gel organ replica. We investigated the internal structure of P-DN gel using Scanning Microscopic Light Scattering (SMILS), a non-contacting and non-destructive.

Effects of soil water table regime on tree community species richness and structure of alluvial forest fragments in Southeast Brazil.

Science.gov (United States)

Silva, A C; Higuchi, P; van den Berg, E

2010-08-01

In order to determine the influence of soil water table fluctuation on tree species richness and structure of alluvial forest fragments, 24 plots were allocated in a point bar forest and 30 plots in five forest fragments located in a floodplain, in the municipality of São Sebastião da Bela Vista, Southeast Brazil, totalizing 54, 10 X 20 m, plots. The information recorded in each plot were the soil water table level, diameter at breast height (dbh), total height and botanical identity off all trees with dbh > 5 cm. The water table fluctuation was assessed through 1 m deep observation wells in each plot. Correlations analysis indicated that sites with shallower water table in the flooding plains had a low number of tree species and high tree density. Although the water table in the point bar remained below the wells during the study period, low tree species richness was observed. There are other events taking place within the point bar forest that assume a high ecological importance, such as the intensive water velocity during flooding and sedimentation processes.

Effects of soil water table regime on tree community species richness and structure of alluvial forest fragments in Southeast Brazil

Directory of Open Access Journals (Sweden)

AC. Silva

Full Text Available In order to determine the influence of soil water table fluctuation on tree species richness and structure of alluvial forest fragments, 24 plots were allocated in a point bar forest and 30 plots in five forest fragments located in a floodplain, in the municipality of São Sebastião da Bela Vista, Southeast Brazil, totalizing 54, 10 X 20 m, plots. The information recorded in each plot were the soil water table level, diameter at breast height (dbh, total height and botanical identity off all trees with dbh > 5 cm. The water table fluctuation was assessed through 1 m deep observation wells in each plot. Correlations analysis indicated that sites with shallower water table in the flooding plains had a low number of tree species and high tree density. Although the water table in the point bar remained below the wells during the study period, low tree species richness was observed. There are other events taking place within the point bar forest that assume a high ecological importance, such as the intensive water velocity during flooding and sedimentation processes.

High-resolution crystal structure of Streptococcus pyogenes β-NAD+ glycohydrolase in complex with its endogenous inhibitor IFS reveals a highly water-rich interface

International Nuclear Information System (INIS)

Yoon, Ji Young; An, Doo Ri; Yoon, Hye-Jin; Kim, Hyoun Sook; Lee, Sang Jae; Im, Ha Na; Jang, Jun Young; Suh, Se Won

2013-01-01

The crystal structure of the complex between the C-terminal domain of Streptococcus pyogenes β-NAD + glycohydrolase and an endogenous inhibitor for SPN was determined at 1.70 Å. It reveals that the interface between the two proteins is highly rich in water molecules. One of the virulence factors produced by Streptococcus pyogenes is β-NAD + glycohydrolase (SPN). S. pyogenes injects SPN into the cytosol of an infected host cell using the cytolysin-mediated translocation pathway. As SPN is toxic to bacterial cells themselves, S. pyogenes possesses the ifs gene that encodes an endogenous inhibitor for SPN (IFS). IFS is localized intracellularly and forms a complex with SPN. This intracellular complex must be dissociated during export through the cell envelope. To provide a structural basis for understanding the interactions between SPN and IFS, the complex was overexpressed between the mature SPN (residues 38–451) and the full-length IFS (residues 1–161), but it could not be crystallized. Therefore, limited proteolysis was used to isolate a crystallizable SPN ct –IFS complex, which consists of the SPN C-terminal domain (SPN ct ; residues 193–451) and the full-length IFS. Its crystal structure has been determined by single anomalous diffraction and the model refined at 1.70 Å resolution. Interestingly, our high-resolution structure of the complex reveals that the interface between SPN ct and IFS is highly rich in water molecules and many of the interactions are water-mediated. The wet interface may facilitate the dissociation of the complex for translocation across the cell envelope

Jacking mechanism for upper internals structure of a liquid metal nuclear reactor

International Nuclear Information System (INIS)

Gillett, J.E.; Wineman, A.L.

1983-01-01

A jacking mechanism for raising the upper internals structure of a liquid metal nuclear reactor which jacking mechanism uses a system of gears and drive shafts to transmit force from a single motor to four mechanically synchronized ball jacks to raise and lower support columns which support the upper internals structure. The support columns each have a pin which rides in a slot in a housing fixed to the reactor head. The pin has two locking plates which can be rotated around the pin to bring the locking plates into engagement with the housing in a raised or a lowered position of the support column such that the support column is then supported by the locking plate and not by the ball screw jacks. (author)

Arbuscular Mycorrhizal Fungi Community Structure, Abundance and Species Richness Changes in Soil by Different Levels of Heavy Metal and Metalloid Concentration

Science.gov (United States)

Krishnamoorthy, Ramasamy; Kim, Chang-Gi; Subramanian, Parthiban; Kim, Ki-Yoon; Selvakumar, Gopal; Sa, Tong-Min

2015-01-01

Arbuscular Mycorrhizal Fungi (AMF) play major roles in ecosystem functioning such as carbon sequestration, nutrient cycling, and plant growth promotion. It is important to know how this ecologically important soil microbial player is affected by soil abiotic factors particularly heavy metal and metalloid (HMM). The objective of this study was to understand the impact of soil HMM concentration on AMF abundance and community structure in the contaminated sites of South Korea. Soil samples were collected from the vicinity of an abandoned smelter and the samples were subjected to three complementary methods such as spore morphology, terminal restriction fragment length polymorphism (T-RFLP) and denaturing gradient gel electrophoresis (DGGE) for diversity analysis. Spore density was found to be significantly higher in highly contaminated soil compared to less contaminated soil. Spore morphological study revealed that Glomeraceae family was more abundant followed by Acaulosporaceae and Gigasporaceae in the vicinity of the smelter. T-RFLP and DGGE analysis confirmed the dominance of Funneliformis mosseae and Rhizophagus intraradices in all the study sites. Claroideoglomus claroideum, Funneliformis caledonium, Rhizophagus clarus and Funneliformis constrictum were found to be sensitive to high concentration of soil HMM. Richness and diversity of Glomeraceae family increased with significant increase in soil arsenic, cadmium and zinc concentrations. Our results revealed that the soil HMM has a vital impact on AMF community structure, especially with Glomeraceae family abundance, richness and diversity. PMID:26035444

Species richness and trophic diversity increase decomposition in a co-evolved food web.

Directory of Open Access Journals (Sweden)

Benjamin Baiser

Full Text Available Ecological communities show great variation in species richness, composition and food web structure across similar and diverse ecosystems. Knowledge of how this biodiversity relates to ecosystem functioning is important for understanding the maintenance of diversity and the potential effects of species losses and gains on ecosystems. While research often focuses on how variation in species richness influences ecosystem processes, assessing species richness in a food web context can provide further insight into the relationship between diversity and ecosystem functioning and elucidate potential mechanisms underpinning this relationship. Here, we assessed how species richness and trophic diversity affect decomposition rates in a complete aquatic food web: the five trophic level web that occurs within water-filled leaves of the northern pitcher plant, Sarracenia purpurea. We identified a trophic cascade in which top-predators--larvae of the pitcher-plant mosquito--indirectly increased bacterial decomposition by preying on bactivorous protozoa. Our data also revealed a facultative relationship in which larvae of the pitcher-plant midge increased bacterial decomposition by shredding detritus. These important interactions occur only in food webs with high trophic diversity, which in turn only occur in food webs with high species richness. We show that species richness and trophic diversity underlie strong linkages between food web structure and dynamics that influence ecosystem functioning. The importance of trophic diversity and species interactions in determining how biodiversity relates to ecosystem functioning suggests that simply focusing on species richness does not give a complete picture as to how ecosystems may change with the loss or gain of species.

Contribution of SELENE-2 geodetic measurements to constrain the lunar internal structure

Science.gov (United States)

Matsumoto, K.; Kikuchi, F.; Yamada, R.; Iwata, T.; Kono, Y.; Tsuruta, S.; Hanada, H.; Goossens, S. J.; Ishihara, Y.; Kamata, S.; Sasaki, S.

2012-12-01

Internal structure and composition of the Moon provide important clue and constraints on theories for how the Moon formed and evolved. The Apollo seismic network has contributed to the internal structure modeling. Efforts have been made to detect the lunar core from the noisy Apollo data (e.g., [1], [2]), but there is scant information about the structure below the deepest moonquakes at about 1000 km depth. On the other hand, there have been geodetic studies to infer the deep structure of the Moon. For example, LLR (Lunar Laser Ranging) data analyses detected a displacement of the lunar pole of rotation, indicating that dissipation is acting on the rotation arising from a fluid core [3]. Bayesian inversion using geodetic data (such as mass, moments of inertia, tidal Love numbers k2 and h2, and quality factor Q) also suggests a fluid core and partial melt in the lower mantle region [4]. Further improvements in determining the second-degree gravity coefficients (which will lead to better estimates of moments of inertia) and the Love number k2 will help us to better constrain the lunar internal structure. Differential VLBI (Very Long Baseline Interferometry) technique, which was used in the Japanese lunar exploration mission SELENE (Sept. 2007 - June 2009), is expected to contribute to better determining the second-degree potential Love number k2 and low-degree gravity coefficients. SELENE will be followed by the future lunar mission SELENE-2 which will carry both a lander and an orbiter. We propose to put the SELENE-type radio sources on these spacecraft in order to accurately estimate k2 and the low-degree gravity coefficients. By using the same-beam VLBI tracking technique, these parameters will be retrieved through precision orbit determination of the orbiter with respect to the lander which serves as a reference. The VLBI mission with the radio sources is currently one of the mission candidates for SELENE-2. We have conducted a preliminary simulation study on the

Preface: 2nd International Conference on Structural Nano Composites (NANOSTRUC2014)

International Nuclear Information System (INIS)

Njuguna, J; Verdejo, R

2014-01-01

The NANOSTRUC 2014 took place at CSIC, Madrid, Spain. The conference theme on 'Nanosciences and Nanotechnologies – Recent Advances towards Nanoproducts and Applications'. The conference aimed to promote activities in various areas of materials and structures by providing a forum for exchange of ideas, presentation of technical achievements and discussion of future directions. NANOSTRUC conferences brings together an international community of experts to discuss the state-of-the-art, new research results, perspectives of future developments, and innovative applications relevant to structural materials, engineering structures, nanocomposites, modelling and simulations, and their related application areas

Spinor Structure and Internal Symmetries

Science.gov (United States)

Varlamov, V. V.

2015-10-01

Spinor structure and internal symmetries are considered within one theoretical framework based on the generalized spin and abstract Hilbert space. Complex momentum is understood as a generating kernel of the underlying spinor structure. It is shown that tensor products of biquaternion algebras are associated with the each irreducible representation of the Lorentz group. Space-time discrete symmetries P, T and their combination PT are generated by the fundamental automorphisms of this algebraic background (Clifford algebras). Charge conjugation C is presented by a pseudoautomorphism of the complex Clifford algebra. This description of the operation C allows one to distinguish charged and neutral particles including particle-antiparticle interchange and truly neutral particles. Spin and charge multiplets, based on the interlocking representations of the Lorentz group, are introduced. A central point of the work is a correspondence between Wigner definition of elementary particle as an irreducible representation of the Poincaré group and SU(3)-description (quark scheme) of the particle as a vector of the supermultiplet (irreducible representation of SU(3)). This correspondence is realized on the ground of a spin-charge Hilbert space. Basic hadron supermultiplets of SU(3)-theory (baryon octet and two meson octets) are studied in this framework. It is shown that quark phenomenologies are naturally incorporated into presented scheme. The relationship between mass and spin is established. The introduced spin-mass formula and its combination with Gell-Mann-Okubo mass formula allows one to take a new look at the problem of mass spectrum of elementary particles.

Rural settlements transition (RST) in a suburban area of metropolis: Internal structure perspectives.

Science.gov (United States)

Ma, Wenqiu; Jiang, Guanghui; Wang, Deqi; Li, Wenqing; Guo, Hongquan; Zheng, Qiuyue

2018-02-15

Rural settlements transition (RST) is one of the most significant indices for understanding the phenomena of rural reconstruction and urban-rural transformation in China. However, a systematic overview of RST is missing, and there is a lack of evidence regarding its characteristics from the internal structure perspectives. In this paper, we systematically explore the RST regarding spatio-temporal change characteristics of internal structure, patterns and impacts on rural environment and development by using practical survey internal land-use data from 2005 to 2015. The results show that the temporal change characteristics of the internal structure of rural settlements demonstrate a tendency for housing land to decrease and other land-use types to increase. The spatial change characteristics reveal that the structure inclines to more complexity and diversity from an exurban area to an urban-rural fringe area. Based on this finding, we identify that rapid development of rural industrialization, more agglomerate and effective industrial land-use, and improved public infrastructure construction are the general RST patterns. Spatially, there exists a physical decay pattern in the exurban area, thereby resulting in the hollowing-out of rural industries and of the population. In addition, the extensive and disorderly pattern in the suburban area causes low efficiency output and serious environmental pollution. The RST pattern in the urban hinterland promoted the "men-environment" compatible development. The study concludes that regional differentiation in patterns and impacts are significant in the process of RST. Future adaptive strategies for rural settlements adjustment should be conducted according to regional characteristics, including socio-economic status, physical geography condition and economic location to improve the rural environmental sustainability. Copyright © 2017 Elsevier B.V. All rights reserved.

Study of the structure of yrast bands of neutron-rich 114-124Pd isotopes

Science.gov (United States)

Chaudhary, Ritu; Devi, Rani; Khosa, S. K.

2018-02-01

The projected shell model calculations have been carried out in the neutron-rich 114-124Pd isotopic mass chain. The results have been obtained for the deformation systematics of E(2+1) and E(4+1)/E({2}+1) values, BCS subshell occupation numbers, yrast spectra, backbending phenomena, B( E2) transition probabilities and g-factors in these nuclei. The observed systematics of E(2+1) values and R_{42} ratios in the 114-124Pd isotopic mass chain indicate that there is a decrease of collectivity as the neutron number increases from 68 to 78. The occurrence of backbending in these nuclei as well as the changes in the calculated B( E2) transition probabilities and g -factors predict that there are changes in the structure of yrast bands in these nuclei. These changes occur at the spin where there is crossing of g-band by 2-qp bands. The predicted backbendings and predicted values of B( E2)s and g-factors in some of the isotopes need to be confirmed experimentally.

Low-Frequency Internal Friction Study on the Structural Changes in Polymer Melts

International Nuclear Information System (INIS)

Xue-Bang, Wu; Qiao-Ling, Xu; Shu-Ying, Shang; Jia-Peng, Shui; Chang-Song, Liu; Zhen-Gang, Zhu

2008-01-01

With the help of the low-frequency internal friction method, we investigate the structural properties of polymer melts, such as amorphous polystyrene (PS), poly(methyl methacrylate) (PMMA), and semi-crystalline poly(ethylene oxide) (PEO). An obvious peak of relaxation type is found in each of the internal friction curves. The peak temperature T p follows the relation T p ≈ (1.15 – 1.18) T g for PS and PMMA melts, while it follows T p ≈ 1.22T m for PEO melt, with T g being the glass transition temperature and T m the melting temperature. Based on the analysis of the features of this peak, it is found that this peak is related to the liquid-liquid transition temperature T u of polymer melts. Mechanism of the liquid-liquid transition is suggested to be thermally-activated collective relaxation through cooperation. This finding may be helpful to understand the structural changes in polymer melts. In addition, the internal friction technique proves to be effective in studying dynamics in polymer melts

The internal structure of magnetic nanoparticles determines the magnetic response

Czech Academy of Sciences Publication Activity Database

Pacáková, Barbara; Kubíčková, Simona; Salas, G.; Mantlíková, Alice; Marciello, M.; Morales, M.P.; Nižňanský, D.; Vejpravová, Jana

2017-01-01

Roč. 9, č. 16 (2017), s. 5129-5140 ISSN 2040-3364 R&D Projects: GA ČR(CZ) GA15-01953S Institutional support: RVO:68378271 Keywords : nanoparticles * single-domain * internal structure Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 7.367, year: 2016

Method of using sacrificial materials for fabricating internal cavities in laminated dielectric structures

Science.gov (United States)

Peterson, Kenneth A [Albuquerque, NM

2009-02-24

A method of using sacrificial materials for fabricating internal cavities and channels in laminated dielectric structures, which can be used as dielectric substrates and package mounts for microelectronic and microfluidic devices. A sacrificial mandrel is placed in-between two or more sheets of a deformable dielectric material (e.g., unfired LTCC glass/ceramic dielectric), wherein the sacrificial mandrel is not inserted into a cutout made in any of the sheets. The stack of sheets is laminated together, which deforms the sheet or sheets around the sacrificial mandrel. After lamination, the mandrel is removed, (e.g., during LTCC burnout), thereby creating a hollow internal cavity in the monolithic ceramic structure.

18 September 2012 - PD Dr. med. Andreas Trojan Researcher, University of Zürich and Mr Marc Forster Independant Swiss Movie Director Switzerland visiting the CMS underground area with Head of international Relations F. Pauss and CMS Collaboration Z. Szillasi.

CERN Multimedia

Jean-Claude Gadmer

2012-01-01

18 September 2012 - PD Dr. med. Andreas Trojan Researcher, University of Zürich and Mr Marc Forster Independant Swiss Movie Director Switzerland visiting the CMS underground area with Head of international Relations F. Pauss and CMS Collaboration Z. Szillasi.

3rd December 2010 - President Swiss Federal Institute of Technology Zürich (ETHZ)President R. Eichler signing the Guest Book with CERN Head of International Relations and ETHZ F. Pauss and visiting CMS service cavern at LHC Point 5.

CERN Multimedia

Maximilien Brice

2010-01-01

3rd December 2010 - President Swiss Federal Institute of Technology Zürich (ETHZ)President R. Eichler signing the Guest Book with CERN Head of International Relations and ETHZ F. Pauss and visiting CMS service cavern at LHC Point 5.

Nitrogen-rich salts of 5,5‧-bistetrazole-1,1‧-diolate: Syntheses, structures and properties

Science.gov (United States)

Yang, Ting; Zhang, Jian-Guo; Zhang, Zhi-Bin; Gozin, Michael

2018-03-01

A series of new nitrogen-rich energetic salts containing 1H,1‧H-[5,5‧-bitetrazole]-1,1‧-diol (BTO) anion and ethane-1,2-diaminium (1), 1-amino-1H-1,2,3-triazol-3-ium (2), 4-amino-4H-1,2,4-triazol-1-ium (3) and 4,5-diamino-4H-1,2,4-triazol-1-ium (4) cations were synthesized by direct salt formation or by metathesis strategy. The structures of energetic salts 1-4 were comprehensively characterized by elemental analysis, mass spectrometry, IR and NMR spectroscopies and by X-ray crystallography. DSC and TGA methods were used to study thermal properties of these salts. Additionally, the non-isothermal kinetic parameters and thermodynamic parameters were calculated by utilizing the Kissinger's and Ozawa-Doyle's methods. The enthalpies of formation for all target compounds in this study were calculated, and their sensitivity to mechanical impact and friction was tested according to BAM guidelines. We found these new energetic salts exhibit good thermal stability and have typical decomposition temperatures above 230 °C, except for the salt 2. All our salts have highly-positive enthalpies of formation (311.1-473.6 kJ mol-1) and are insensitive to impact and friction stimuli (>40 J, 120 N). With a high nitrogen-rich content, high enthalpy of formation, good thermostability and very low sensitivity to impact, some of these new salts may have a potential for application in the field of environmentally friendly insensitive energetic materials.

A RICH detector for strangeness physics in Hall A at Jefferson Lab

International Nuclear Information System (INIS)

Cusanno, F.; Garibaldi, F.; Cisbani, E.; Colilli, S.; De Cataldo, G.; De Leo, R.; Giuliani, F.; Gricia, M.; Lagamba, L.; Lucentini, M.; Reitz, B.; Santavenere, F.; Urciuoli, G.M.

2004-01-01

The high-resolution hypernuclear spectroscopy experiment at Jefferson Lab, Hall A (E94-107), needs unambiguous kaon identification. Due to the huge pion and proton background, the standard Hall A hadron particle identification, based on a time of flight and two aerogel threshold Cherenkov detectors, is not sufficient. For this task a proximity focusing C 6 F 14 /CsI RICH has been built. Recently, after some improvements to the mechanical structure of its wire chamber and to its electronics rate capability, the RICH has been tested with cosmic rays. This paper represents a status report of the RICH detector

PIV measurement of internal structure of diesel fuel spray

Energy Technology Data Exchange (ETDEWEB)

Cao, Z M [Ecotechnology System Lab., Yokohama National Univ. (Japan); Nishino, K [Div. of Artificial Environment and Systems, Yokohama National Univ. (Japan); Mizuno, S [Yokohama National Univ. (Japan); Torii, K [Dept. of Mechanical Engineering and Materials Science, Yokohama National Univ. (Japan)

2000-12-01

This paper reports particle image velocimetry (PIV) measurements of diesel fuel spray injected from a single-hole nozzle at injection pressures ranging from 30 to 70 MPa, which are comparable to partial-load operating conditions of commercial diesel engines. The fuel is injected into a non-combusting environment pressurized up to 2.0 MPa. A laser-induced fluorescent (LIF) technique is utilized to visualize internal structures of fuel sprays formed by densely-distributing droplets. A specially designed synchronization system is developed to acquire double-frame spray images at an arbitrary time delay after injection. A direct cross-correlation PIV technique is applied to measure instantaneous droplet velocity distribution. Unique large-scale structures in droplet concentration, called 'branch-like structures' by Azetsu et al. (1990), are observed and shown to be associated with active vortical motions, which appear to be responsible for the mixing between droplets and the surrounding gas. It is found that the droplets tend to move out of the vortical structures and accumulate in the regions of low vorticity. Some other interesting features concerning droplet velocity fields are also presented. (orig.)

Use of ephippial morphology to assess richness of anomopods: potentials and pitfalls

Directory of Open Access Journals (Sweden)

Luc DE MEESTER

2004-09-01

Full Text Available Zooplankton species richness is typically assessed through analysis of active community samples. These samples ought to be collected at many different locations in the lake and at multiple occasions throughout the year so as to cover the spatial and temporal heterogeneity in active community structure. A number of studies have shown that high numbers of species can be retrieved with a limited effort through hatching of dormant eggs isolated from lake sediments. However, dormant eggs of different species differ in their propensities to hatch, resulting in biased assessments of species composition, abundance and richness. In this paper, we explore the potentials and pitfalls of a third method to assess cladoceran species richness. For twenty European lakes, we identified the number of ephippium morphotypes in sediment samples taken on a single occasion. The morphotype richness was well correlated with species richness as assessed through hatching of dormant forms and through analysis of active community samples covering a six month period. However, not all species had a species-specific ephippial morphotype, consequently resulting in an underestimation of true species richness.

A Metastatic Lipid-Rich Carcinoma of the Mammary Gland in a Female Cat: Clinicopathological, Histopathological and Immunohistochemical Features

Directory of Open Access Journals (Sweden)

Adrian Florin GAL

2017-11-01

Full Text Available Lipid-rich invasive human breast cancer is a rare enigmatic entity among special types of infiltrating duct carcinoma. Our paper reports a lipid-rich mammary carcinoma in a female cat with the gross, microscopic and immunohistochemical description of the tumor. A 13-year-old intact adult female, mixed-breed cat was presented by the owner to the Laboratory of Pathologic Anatomy from the Faculty of Veterinary Medicine Cluj-Napoca, Romania. A complete necropsy examination was performed in our laboratory. The tissue samples were collected and processed by paraffin technique for further histological, histochemical, immunofluorescence and immunohistochemical examination. During the necropsy examination, a subcutaneous mass was discovered on the chest. Several variably sized, well-demarcated neoplasms were noted in the right axillary lymph node, right thoracic wall, pleura, lungs, liver, spleen and kidney. Histologically, the cells frequently formed tubuloacinar structures. The morphology of the described tumor showed features of a poorly differentiated mammary carcinoma. Numerous tumoral cells were large and polygonal, with abundant cytoplasm that showed foam-like cytoplasm. The tumoral cells contained either multiple small or large and solitary vacuoles that pushed the nucleus to the periphery of the cell. Intracytoplasmic vacuoles of the neoplastic cells were positive for Oil-Red-O and negatively with Periodic Acid–Schiff. As for immunofluorescence/immunohistochemistry, nonvacuolated and vacuolated neoplastic cells were positive for cytokeratin and negative for vimentin. Histochemical and immunohistochemical analysis support a diagnosis of lipid-rich mammary carcinoma. This is the second reliable record of a lipid-rich mammary carcinoma in female cat and the first one with internal metastases.

Primary vesicles, vesicle-rich segregation structures and recognition of primary and secondary porosities in lava flows from the Paraná igneous province, southern Brazil

Science.gov (United States)

Barreto, Carla Joana S.; de Lima, Evandro F.; Goldberg, Karin

2017-04-01

This study focuses on a volcanic succession of pāhoehoe to rubbly lavas of the Paraná-Etendeka Province exposed in a single road profile in southernmost Brazil. This work provides an integrated approach for examining primary vesicles and vesicle-rich segregation structures at the mesoscopic scale. In addition, this study provides a quantitative analysis of pore types in thin section. We documented distinct distribution patterns of vesicle and vesicle-rich segregation structures according to lava thickness. In compound pāhoehoe lavas, the cooling allows only vesicles (pipe vesicles to be frozen into place. In inflated pāhoehoe lavas, vesicles of different sizes are common, including pipe vesicles, and also segregation structures such as proto-cylinders, cylinders, cylinder sheets, vesicle sheets, and pods. In rubbly lavas, only vesicles of varying sizes occur. Gas release from melt caused the formation of primary porosity, while hydrothermal alteration and tectonic fracturing are the main processes that generated secondary porosity. Although several forms of porosity were created in the basaltic lava flows, the precipitation of secondary minerals within the pores has tended to reduce the original porosities. Late-stage fractures could create efficient channel networks for possible hydrocarbon/groundwater migration and entrapment owing to their ability to connect single pores. Quantitative permeability data should be gathered in future studies to confirm the potential of these lavas for store hydrocarbons or groundwater.

Species Richness and Community Structure on a High Latitude Reef: Implications for Conservation and Management

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Wayne Houston

2011-07-01

Full Text Available In spite of the wealth of research on the Great Barrier Reef, few detailed biodiversity assessments of its inshore coral communities have been conducted. Effective conservation and management of marine ecosystems begins with fine-scale biophysical assessments focused on diversity and the architectural species that build the structural framework of the reef. In this study, we investigate key coral diversity and environmental attributes of an inshore reef system surrounding the Keppel Bay Islands near Rockhampton in Central Queensland, Australia, and assess their implications for conservation and management. The Keppels has much higher coral diversity than previously found. The average species richness for the 19 study sites was ~40 with representatives from 68% of the ~244 species previously described for the southern Great Barrier Reef. Using scleractinian coral species richness, taxonomic distinctiveness and coral cover as the main criteria, we found that five out of 19 sites had particularly high conservation value. A further site was also considered to be of relatively high value. Corals at this site were taxonomically distinct from the others (representatives of two families were found here but not at other sites and a wide range of functionally diverse taxa were present. This site was associated with more stressful conditions such as high temperatures and turbidity. Highly diverse coral communities or biodiversity ‘hotspots’ and taxonomically distinct reefs may act as insurance policies for climatic disturbance, much like Noah’s Arks for reefs. While improving water quality and limiting anthropogenic impacts are clearly important management initiatives to improve the long-term outlook for inshore reefs, identifying, mapping and protecting these coastal ‘refugia’ may be the key for ensuring their regeneration against catastrophic climatic disturbance in the meantime.

Internal energy relaxation in shock wave structure

International Nuclear Information System (INIS)

Josyula, Eswar; Suchyta, Casimir J.; Boyd, Iain D.; Vedula, Prakash

2013-01-01

The Wang Chang-Uhlenbeck (WCU) equation is numerically integrated to characterize the internal structure of Mach 3 and Mach 5 shock waves in a gas with excitation in the internal energy states for the treatment of inelastic collisions. Elastic collisions are modeled with the hard sphere collision model and the transition rates for the inelastic collisions modified appropriately using probabilities based on relative velocities of the colliding particles. The collision integral is evaluated by the conservative discrete ordinate method [F. Tcheremissine, “Solution of the Boltzmann kinetic equation for high-speed flows,” Comput. Math. Math. Phys. 46, 315–329 (2006); F. Cheremisin, “Solution of the Wang Chang-Uhlenbeck equation,” Dokl. Phys. 47, 487–490 (2002)] developed for the Boltzmann equation. For the treatment of the diatomic molecules, the internal energy modes in the Boltzmann equation are described quantum mechanically given by the WCU equation. As a first step in the treatment of the inelastic collisions by the WCU equation, a two- and three-quantum system is considered to study the effect of the varying of (1) the inelastic cross section and (2) the energy gap between the quantum energy states. An alternative method, the direct simulation Monte Carlo method, is used for the Mach 3 shock wave to ensure the consistency of implementation in the two methods and there is an excellent agreement between the two methods. The results from the WCU implementation showed consistent trends for the Mach 3 and Mach5 standing shock waves simulations. Inelastic contributions change the downstream equilibrium state and allow the flow to transition to the equilibrium state further upstream

Impact of casein and egg white proteins on the structure of wheat gluten-based protein-rich food.

Science.gov (United States)

Wouters, Arno G B; Rombouts, Ine; Lagrain, Bert; Delcour, Jan A

2016-02-01

There is a growing interest in texturally and nutritionally satisfying vegetable alternatives to meat. Wheat gluten proteins have unique functional properties but a poor nutritional value in comparison to animal proteins. This study investigated the potential of egg white and bovine milk casein with well-balanced amino acid composition to increase the quality of wheat gluten-based protein-rich foods. Heating a wheat gluten (51.4 g)-water (100.0 mL) blend for 120 min at 100 °C increased its firmness less than heating a wheat gluten (33.0 g)-freeze-dried egg white (16.8 g)-water (100.0 mL) blend. In contrast, the addition of casein to the gluten-water blend negatively impacted firmness after heating. Firmness was correlated with loss of protein extractability in sodium dodecyl sulfate containing medium during heating, which was higher with egg white than with casein. Even more, heat-induced polymerization of the gluten-water blend with egg white but not with casein was greater than expected from the losses in extractability of gluten and egg white on their own. Structure formation was favored by mixing gluten with egg white but not with casein. These observations were linked to the intrinsic polymerization behavior of egg white and casein, but also to their interaction with gluten. Thus not all nutritionally suitable proteins can be used for enrichment of gluten-based protein-rich foods. © 2015 Society of Chemical Industry.

Cultural, Social, and Economic Capital Constructs in International Assessments: An Evaluation Using Exploratory Structural Equation Modeling

Science.gov (United States)

Caro, Daniel H.; Sandoval-Hernández, Andrés; Lüdtke, Oliver

2014-01-01

The article employs exploratory structural equation modeling (ESEM) to evaluate constructs of economic, cultural, and social capital in international large-scale assessment (LSA) data from the Progress in International Reading Literacy Study (PIRLS) 2006 and the Programme for International Student Assessment (PISA) 2009. ESEM integrates the…

D19S Mutation of the Cationic, Cysteine-Rich Protein PAF: Novel Insights into Its Structural Dynamics, Thermal Unfolding and Antifungal Function.

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Christoph Sonderegger

Full Text Available The cysteine-rich, cationic, antifungal protein PAF is abundantly secreted into the culture supernatant of the filamentous Ascomycete Penicillium chrysogenum. The five β-strands of PAF form a compact β-barrel that is stabilized by three disulphide bonds. The folding of PAF allows the formation of four surface-exposed loops and distinct charged motifs on the protein surface that might regulate the interaction of PAF with the sensitive target fungus. The growth inhibitory activity of this highly stable protein against opportunistic fungal pathogens provides great potential in antifungal drug research. To understand its mode of action, we started to investigate the surface-exposed loops of PAF and replaced one aspartic acid at position 19 in loop 2 that is potentially involved in PAF active or binding site, with a serine (Asp19 to Ser19. We analysed the overall effects, such as unfolding, electrostatic changes, sporadic conformers and antifungal activity when substituting this specific amino acid to the fairly indifferent amino acid serine. Structural analyses revealed that the overall 3D solution structure is virtually identical with that of PAF. However, PAFD19S showed slightly increased dynamics and significant differences in the surface charge distribution. Thermal unfolding identified PAFD19S to be rather a two-state folder in contrast to the three-state folder PAF. Functional comparison of PAFD19S and PAF revealed that the exchange at residue 19 caused a dramatic loss of antifungal activity: the binding and internalization of PAFD19S by target cells was reduced and the protein failed to trigger an intracellular Ca2+ response, all of which are closely linked to the antifungal toxicity of PAF. We conclude that the negatively charged residue Asp19 in loop 2 is essential for full function of the cationic protein PAF.

Internal inspection of reinforced concrete for nuclear structures using shear wave tomography

International Nuclear Information System (INIS)

Scott, David B.

2013-01-01

Highlights: • Aging of reinforced concrete used for worldwide nuclear structures is increasing and necessitating evaluation. • Nondestructive evaluation is a tool for assessing the condition of reinforced concrete of nuclear structures. • Ultrasonic shear wave tomography as a stress wave technique has begun to be utilized for investigation of concrete material. • A study using ultrasonic shear wave tomography indicates anomalies vital to the long-term operation of the structure. • The use of this technique has shown to successfully evaluate the internal state of reinforced concrete members. - Abstract: Reinforced concrete is important for nuclear related structures. Therefore, the integrity of structural members consisting of reinforced concrete is germane to the safe operation and longevity of these facilities. Many issues that reduce the likelihood of safe operation and longevity are not visible on the surface of reinforced concrete material. Therefore, an investigation of reinforced concrete material should include techniques which will allow peering into the concrete member and determining its internal state. The performance of nondestructive evaluations is pursuant to this goal. Some of the categories of nondestructive evaluations are electrochemical, magnetism, ground penetrating radar, and ultrasonic testing. A specific ultrasonic testing technique, namely ultrasonic shear wave tomography, is used to determine presence and extent of voids, honeycombs, cracks perpendicular to the surface, and/or delamination. This technique, and others similar to it, has been utilized in the nuclear industry to determine structural conditions

Learning about the internal structure of categories through classification and feature inference.

Science.gov (United States)

Jee, Benjamin D; Wiley, Jennifer

2014-01-01

Previous research on category learning has found that classification tasks produce representations that are skewed toward diagnostic feature dimensions, whereas feature inference tasks lead to richer representations of within-category structure. Yet, prior studies often measure category knowledge through tasks that involve identifying only the typical features of a category. This neglects an important aspect of a category's internal structure: how typical and atypical features are distributed within a category. The present experiments tested the hypothesis that inference learning results in richer knowledge of internal category structure than classification learning. We introduced several new measures to probe learners' representations of within-category structure. Experiment 1 found that participants in the inference condition learned and used a wider range of feature dimensions than classification learners. Classification learners, however, were more sensitive to the presence of atypical features within categories. Experiment 2 provided converging evidence that classification learners were more likely to incorporate atypical features into their representations. Inference learners were less likely to encode atypical category features, even in a "partial inference" condition that focused learners' attention on the feature dimensions relevant to classification. Overall, these results are contrary to the hypothesis that inference learning produces superior knowledge of within-category structure. Although inference learning promoted representations that included a broad range of category-typical features, classification learning promoted greater sensitivity to the distribution of typical and atypical features within categories.

The relative importance of climate and vegetation properties on patterns of North American breeding bird species richness

International Nuclear Information System (INIS)

Goetz, Scott J; Sun, Mindy; Zolkos, Scott; Hansen, Andy; Dubayah, Ralph

2014-01-01

Recent advances in remote sensing and ecological modeling warrant a timely and robust investigation of the ecological variables that underlie large-scale patterns of breeding bird species richness, particularly in the context of intensifying land use and climate change. Our objective was to address this need using an array of bioclimatic and remotely sensed data sets representing vegetation properties and structure, and other aspects of the physical environment. We first build models of bird species richness across breeding bird survey (BBS) routes, and then spatially predict richness across the coterminous US at moderately high spatial resolution (1 km). Predictor variables were derived from various sources and maps of species richness were generated for four groups (guilds) of birds with different breeding habitat affiliation (forest, grassland, open woodland, scrub/shrub), as well as all guilds combined. Predictions of forest bird distributions were strong (R 2 = 0.85), followed by grassland (0.76), scrub/shrub (0.63) and open woodland (0.60) species. Vegetation properties were generally the strongest determinants of species richness, whereas bioclimatic and lidar-derived vertical structure metrics were of variable importance and dependent upon the guild type. Environmental variables (climate and the physical environment) were also frequently selected predictors, but canopy structure variables were not as important as expected based on more local to regional scale studies. Relatively sparse sampling of canopy structure metrics from the satellite lidar sensor may have reduced their importance relative to other predictor variables across the study domain. We discuss these results in the context of the ecological drivers of species richness patterns, the spatial scale of bird diversity analyses, and the potential of next generation space-borne lidar systems relevant to vegetation and ecosystem studies. This study strengthens current understanding of bird species�

40 CFR 60.4240 - What are my compliance requirements if I am a manufacturer of stationary SI internal combustion...

Science.gov (United States)

2010-07-01

... I am a manufacturer of stationary SI internal combustion engines >19 KW (25 HP) that are rich burn... I am a manufacturer of stationary SI internal combustion engines >19 KW (25 HP) that are rich burn..., and must test their engines as specified in that part. Stationary SI internal combustion engine...

Examining the Dynamic Structure of Daily Internalizing and Externalizing Behavior at Multiple Levels of Analysis

Directory of Open Access Journals (Sweden)

Aidan G.C. Wright

2015-12-01

Full Text Available Psychiatric diagnostic covariation suggests that the underlying structure of psychopathology is not one of circumscribed disorders. Quantitative modeling of individual differences in diagnostic patterns has uncovered several broad domains of mental disorder liability, of which the Internalizing and Externalizing spectra have garnered the greatest support. These dimensions have generally been estimated from lifetime or past-year comorbidity patters, which are distal from the covariation of symptoms and maladaptive behavior that ebb and flow in daily life. In this study, structural models are applied to daily diary data (Median = 94 days of maladaptive behaviors collected from a sample (N = 101 of individuals diagnosed with personality disorders. Using multilevel and unified structural equation modeling, between-person, within-person, and person-specific structures were estimated from 16 behaviors that are encompassed by the Internalizing and Externalizing spectra. At the between-person level (i.e., individual differences in average endorsement across days we found support for a two-factor Internalizing-Externalizing model, which exhibits significant associations with corresponding diagnostic spectra. At the within-person level (i.e., dynamic covariation among daily behavior pooled across individuals we found support for a more differentiated, four-factor, Negative Affect-Detachment-Hostility-Impulsivity structure. Finally, we demonstrate that the person-specific structures of associations between these four domains are highly idiosyncratic.

Chemical detection of cysteine-rich circular petides in selected ...

African Journals Online (AJOL)

Cysteine-rich circular peptides (CRCs) comprise a large family of gene encoded and low molecular weight polypeptides that has recently engaged the attention of scientists. This class of peptides exhibit a continuous circular configuration and a cystine knot backbone, which defines their resilient nature-directed structural ...

Organizational Structures for International Universities: Implications for Campus Autonomy, Academic Freedom, Collegiality, and Conflict

Science.gov (United States)

Edwards, Ron; Crosling, Glenda; Lim, Ngat-Chin

2014-01-01

One significant form of transnational higher education is the International Branch Campus (IBC), in effect an "outpost" of the parent institution located in another country. Its organizational structure is alignable with offshore subsidiaries of multinational corporations (MNCs). The implications of organizational structure for academic…

Surface and Internal Waves due to a Moving Load on a Very Large Floating Structure

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Taro Kakinuma

2012-01-01

Full Text Available Interaction of surface/internal water waves with a floating platform is discussed with nonlinearity of fluid motion and flexibility of oscillating structure. The set of governing equations based on a variational principle is applied to a one- or two-layer fluid interacting with a horizontally very large and elastic thin plate floating on the water surface. Calculation results of surface displacements are compared with the existing experimental data, where a tsunami, in terms of a solitary wave, propagates across one-layer water with a floating thin plate. We also simulate surface and internal waves due to a point load, such as an airplane, moving on a very large floating structure in shallow water. The wave height of the surface or internal mode is amplified when the velocity of moving point load is equal to the surface- or internal-mode celerity, respectively.

Internal Flow Structures in Columnar Jointed Basalt from HREPPHÓLAR, Iceland

Science.gov (United States)

Mattsson, H. B.; Bosshard, S. A.; Hetenyi, G.; Almqvist, B.; Hirt, A. M.; Caricchi, L.; Caddick, M.

2010-12-01

Columnar jointed basalt from Hrepphólar in southern Iceland display spectacular internal structures when cut. These structures follow the overall orientation of the columns and display semi-circular to circular features when cross-cut. It was previously believed that these internal structures formed as a result of alteration due to circulation of meteoric water within the column-bounding fractures after emplacement. However, new field observations of viscous fingering within the columns and the fact that approximately 80% of the semi-circular features are found within the column whereas the remaining 20% are cut by the column-bounding fractures clearly shows that these internal structures must have formed prior to crack-propagation (and are thus primary features). Here we present the results of textural and petrological analyses through a cross-section of a column, in combination with magnetic susceptibility and anisotropy measurements of the same samples. The variation in textures and geochemistry can be attributed to the presence of diffuse banding caused by variations in the modal proportions of the main phenocryst phases (i.e., plagioclase, clinopyroxene, olivine and titanomagnetite/ilmenite). Orientation of plagioclase laths and titanomagnetite crystals (based on measurements in thin sections and AMS-measurements) are consistent with vertical flow alignment. Nowhere in the column can evidence for downwards flow be found (excluding the possibility of small-scale convection cells generating these features). It is proposed here, that the volume decrease associated with solidification (typically 10-15 vol.% for basaltic systems) and the increasing weight of the overlying crust results in upwelling of partially crystallized material into the centre of the columns. Preliminary numerical modeling indicates that the isotherms within individual columns become steeper with increasing depth in a lava flow (allowing for larger displacement distances). We propose that

Internal Stress Monitoring of In-Service Structural Steel Members with Ultrasonic Method.

Science.gov (United States)

Li, Zuohua; He, Jingbo; Teng, Jun; Wang, Ying

2016-03-23

Internal stress in structural steel members is an important parameter for steel structures in their design, construction, and service stages. However, it is hard to measure via traditional approaches. Among the existing non-destructive testing (NDT) methods, the ultrasonic method has received the most research attention. Longitudinal critically refracted (Lcr) waves, which propagate parallel to the surface of the material within an effective depth, have shown great potential as an effective stress measurement approach. This paper presents a systematic non-destructive evaluation method to determine the internal stress in in-service structural steel members using Lcr waves. Based on theory of acoustoelasticity, a stress evaluation formula is derived. Factor of stress to acoustic time difference is used to describe the relationship between stress and measurable acoustic results. A testing facility is developed and used to demonstrate the performance of the proposed method. Two steel members are measured by using the proposed method and the traditional strain gauge method for verification. Parametric studies are performed on three steel members and the aluminum plate to investigate the factors that influence the testing results. The results show that the proposed method is effective and accurate for determining stress in in-service structural steel members.

Internal Stress Monitoring of In-Service Structural Steel Members with Ultrasonic Method

Science.gov (United States)

Li, Zuohua; He, Jingbo; Teng, Jun; Wang, Ying

2016-01-01

Internal stress in structural steel members is an important parameter for steel structures in their design, construction, and service stages. However, it is hard to measure via traditional approaches. Among the existing non-destructive testing (NDT) methods, the ultrasonic method has received the most research attention. Longitudinal critically refracted (Lcr) waves, which propagate parallel to the surface of the material within an effective depth, have shown great potential as an effective stress measurement approach. This paper presents a systematic non-destructive evaluation method to determine the internal stress in in-service structural steel members using Lcr waves. Based on theory of acoustoelasticity, a stress evaluation formula is derived. Factor of stress to acoustic time difference is used to describe the relationship between stress and measurable acoustic results. A testing facility is developed and used to demonstrate the performance of the proposed method. Two steel members are measured by using the proposed method and the traditional strain gauge method for verification. Parametric studies are performed on three steel members and the aluminum plate to investigate the factors that influence the testing results. The results show that the proposed method is effective and accurate for determining stress in in-service structural steel members. PMID:28773347

Instabilities and soot formation in spherically expanding, high pressure, rich, iso-octane-air flames

International Nuclear Information System (INIS)

Lockett, R D

2006-01-01

Flame instabilities, cellular structures and soot formed in high pressure, rich, spherically expanding iso-octane-air flames have been studied experimentally using high speed Schlieren cinematography, OH fluorescence, Mie scattering and laser induced incandescence. Cellular structures with two wavelength ranges developed on the flame surface. The larger wavelength cellular structure was produced by the Landau-Darrieus hydrodynamic instability, while the short wavelength cellular structure was produced by the thermal-diffusive instability. Large negative curvature in the short wavelength cusps caused local flame quenching and fracture of the flame surface. In rich flames with equivalence ratio φ > 1.8, soot was formed in a honeycomb-like structure behind flame cracks associated with the large wavelength cellular structure induced by the hydrodynamic instability. The formation of soot precursors through low temperature pyrolysis was suggested as a suitable mechanism for the initiation of soot formation behind the large wavelength flame cracks

Instabilities and soot formation in spherically expanding, high pressure, rich, iso-octane-air flames

Energy Technology Data Exchange (ETDEWEB)

Lockett, R D [School of Engineering and Mathematical Sciences, City University, Northampton Square, London EC1V OHB (United Kingdom)

2006-07-15

Flame instabilities, cellular structures and soot formed in high pressure, rich, spherically expanding iso-octane-air flames have been studied experimentally using high speed Schlieren cinematography, OH fluorescence, Mie scattering and laser induced incandescence. Cellular structures with two wavelength ranges developed on the flame surface. The larger wavelength cellular structure was produced by the Landau-Darrieus hydrodynamic instability, while the short wavelength cellular structure was produced by the thermal-diffusive instability. Large negative curvature in the short wavelength cusps caused local flame quenching and fracture of the flame surface. In rich flames with equivalence ratio {phi} > 1.8, soot was formed in a honeycomb-like structure behind flame cracks associated with the large wavelength cellular structure induced by the hydrodynamic instability. The formation of soot precursors through low temperature pyrolysis was suggested as a suitable mechanism for the initiation of soot formation behind the large wavelength flame cracks.

A Rich Man, Poor Man Story of S-Adenosylmethionine and Cobalamin Revisited.

Science.gov (United States)

Bridwell-Rabb, Jennifer; Grell, Tsehai A J; Drennan, Catherine L

2018-06-20

S-adenosylmethionine (AdoMet) has been referred to as both "a poor man's adenosylcobalamin (AdoCbl)" and "a rich man's AdoCbl," but today, with the ever-increasing number of functions attributed to each cofactor, both appear equally rich and surprising. The recent characterization of an organometallic species in an AdoMet radical enzyme suggests that the line that differentiates them in nature will be constantly challenged. Here, we compare and contrast AdoMet and cobalamin (Cbl) and consider why Cbl-dependent AdoMet radical enzymes require two cofactors that are so similar in their reactivity. We further carry out structural comparisons employing the recently determined crystal structure of oxetanocin-A biosynthetic enzyme OxsB, the first three-dimensional structural data on a Cbl-dependent AdoMet radical enzyme. We find that the structural motifs responsible for housing the AdoMet radical machinery are largely conserved, whereas the motifs responsible for binding additional cofactors are much more varied.

Comparison of the associative structure of two different types of rich coals and their coking properties

Energy Technology Data Exchange (ETDEWEB)

Hengfu Shui; Changhui Lin; Meng Zhang; Zhicai Wang; Mingdong Zheng [Anhui University of Technology, Maanshan (China). School of Chemistry and Chemical Engineering

2010-07-15

Solvent extractions of two different types of Chinese rich coals i.e. Aiweiergou coal (AG) and Zaozhuang coal (ZZ) using the mixed solvent of carbon disulfide/N-methyl-2-pyrrolidinone (CS{sub 2}/NMP) with different mixing ratios were carried out and the caking indexes of the extracted residues were measured. It was found that the extracted residues from the two types of coals showed different changing tendencies of the caking indexes with the extraction yield. When the extraction yield attained about 50% for ZZ coal, the extracted residue had no caking property. However for AG coal, when the extraction yield reached the maximum of 63.5%, the corresponding extracted residue still had considerable caking property with the caking index of 25. This difference indicated the different associative structure of the two coals although they are of the same coalification. Hydro-thermal treatment of the two rich coals gave different extract fractionation distributions for the treated coals compared to those of raw coals respectively. The coking property evaluations of the two coals and their hydro-thermally treated ones were carried out in a crucible coking determination. The results showed that the hydro-thermal treatment could greatly improve the micro-strengths of the resulting coke from the two coals, and the improvement was more significant for the more aggregated AG coal. The reactivities of hydro-thermally treated AG coal blends were almost the same as those of raw coal blends. The higher coke reactivities of AG raw coal and its hydro-thermally treated ones than those of ZZ coal might be attributed to its special ash composition. 20 refs.,4 figs., 5 tabs.

INTERNAL STRUCTURE OF ASTEROIDS HAVING SURFACE SHEDDING DUE TO ROTATIONAL INSTABILITY

Energy Technology Data Exchange (ETDEWEB)

Hirabayashi, Masatoshi [Research Associate, Colorado Center for Astrodynamics Research, Aerospace Engineering Sciences, University of Colorado Boulder (United States); Sánchez, Diego Paul [Senior Research Associate, Colorado Center for Astrodynamics Research, Aerospace Engineering Sciences, University of Colorado Boulder (United States); Scheeres, Daniel J., E-mail: masatoshi.hirabayashi@colorado.edu [Richard Seebass Chair, Professor, Colorado Center for Astrodynamics Research, Aerospace Engineering Sciences, University of Colorado Boulder (United States)

2015-07-20

Surface shedding of an asteroid is a failure mode where surface materials fly off due to strong centrifugal forces beyond the critical spin period, while the internal structure does not deform significantly. This paper proposes a possible structure of an asteroid interior that leads to surface shedding due to rapid rotation rates. A rubble pile asteroid is modeled as a spheroid composed of a surface shell and a concentric internal core, the entire assembly called the test body. The test body is assumed to be uniformly rotating around a constant rotation axis. We also assume that while the bulk density and the friction angle are constant, the cohesion of the surface shell is different from that of the internal core. First, developing an analytical model based on limit analysis, we provide the upper and lower bounds for the actual surface shedding condition. Second, we use a Soft-sphere Discrete Element Method (SSDEM) to study dynamical deformation of the test body due to a quasi-static spin-up. In this paper we show the consistency of both approaches. Additionally, the SSDEM simulations show that the initial failure always occurs locally and not globally. In addition, as the core becomes larger, the size of lofted components becomes smaller. These results imply that if there is a strong core in a progenitor body, surface shedding is the most likely failure mode.

Identifying the community structure of the food-trade international multi-network

Science.gov (United States)

Torreggiani, S.; Mangioni, G.; Puma, M. J.; Fagiolo, G.

2018-05-01

Achieving international food security requires improved understanding of how international trade networks connect countries around the world through the import-export flows of food commodities. The properties of international food trade networks are still poorly documented, especially from a multi-network perspective. In particular, nothing is known about the multi-network’s community structure. Here we find that the individual crop-specific layers of the multi-network have densely connected trading groups, a consistent characteristic over the period 2001–2011. Further, the multi-network is characterized by low variability over this period but with substantial heterogeneity across layers in each year. In particular, the layers are mostly assortative: more-intensively connected countries tend to import from and export to countries that are themselves more connected. We also fit econometric models to identify social, economic and geographic factors explaining the probability that any two countries are co-present in the same community. Our estimates indicate that the probability of country pairs belonging to the same food trade community depends more on geopolitical and economic factors—such as geographical proximity and trade-agreement co-membership—than on country economic size and/or income. These community-structure findings of the multi-network are especially valuable for efforts to understand past and emerging dynamics in the global food system, especially those that examine potential ‘shocks’ to global food trade.

INTERNAL STRUCTURE OF ASTEROIDS HAVING SURFACE SHEDDING DUE TO ROTATIONAL INSTABILITY

International Nuclear Information System (INIS)

Hirabayashi, Masatoshi; Sánchez, Diego Paul; Scheeres, Daniel J.

2015-01-01

Surface shedding of an asteroid is a failure mode where surface materials fly off due to strong centrifugal forces beyond the critical spin period, while the internal structure does not deform significantly. This paper proposes a possible structure of an asteroid interior that leads to surface shedding due to rapid rotation rates. A rubble pile asteroid is modeled as a spheroid composed of a surface shell and a concentric internal core, the entire assembly called the test body. The test body is assumed to be uniformly rotating around a constant rotation axis. We also assume that while the bulk density and the friction angle are constant, the cohesion of the surface shell is different from that of the internal core. First, developing an analytical model based on limit analysis, we provide the upper and lower bounds for the actual surface shedding condition. Second, we use a Soft-sphere Discrete Element Method (SSDEM) to study dynamical deformation of the test body due to a quasi-static spin-up. In this paper we show the consistency of both approaches. Additionally, the SSDEM simulations show that the initial failure always occurs locally and not globally. In addition, as the core becomes larger, the size of lofted components becomes smaller. These results imply that if there is a strong core in a progenitor body, surface shedding is the most likely failure mode

The CAPRICE RICH detector

Energy Technology Data Exchange (ETDEWEB)

Basini, G. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Codino, A.; Grimani, C. [Perugia Univ. (Italy)]|[INFN, Perugia (Italy); De Pascale, M.P. [Rome Univ. `Tor Vergata` (Italy). Dip. di Fisica]|[INFN, Sezione Univ. `Tor Vergata` Rome (Italy); Cafagna, F. [Bari Univ. (Italy)]|[INFN, Bari (Italy); Golden, R.L. [New Mexico State Univ., Las Cruces, NM (United States). Particle Astrophysics Lab.; Brancaccio, F.; Bocciolini, M. [Florence Univ. (Italy)]|[INFN, Florence (Italy); Barbiellini, G.; Boezio, M. [Trieste Univ. (Italy)]|[INFN, Trieste (Italy)

1995-09-01

A compact RICH detector has been developed and used for particle identification in a balloon borne spectrometer to measure the flux of antimatter in the cosmic radiation. This is the first RICH detector ever used in space experiments that is capable of detecting unit charged particles, such as antiprotons. The RICH and all other detectors performed well during the 27 hours long flight.

Draa Sfar, Morocco: A Visean (331 Ma) pyrrhotite-rich, polymetallic volcanogenic massive sulphide deposit in a Hercynian sediment-dominant terrane

OpenAIRE

Marcoux , Eric; Belkabir , Abdelhay; Gibson , Harold L.; Lentz , David; Ruffet , Gilles

2008-01-01

International audience; Draa Sfar is a Visean, stratabound, volcanogenic massive sulphide ore deposit hosted by a Hercynian carbonaceous, black shale-rich succession of the Jebilet terrane, Morocco. The ore deposit contains 10 Mt grading 5.3 wt.% Zn, 2 wt.% Pb, and 0.3 wt.% Cu within two main massive sulphides orebodies, Tazakourt (Zn-rich) and Sidi M'Barek (Zn–Cu rich). Pyrrhotite is by far the dominant sulphide (70 to 95% of total sulphides), sphalerite is fairly abundant, chalcopyrite and ...

Production structure and international competition position of the German environmental protection economy; Produktionsstruktur und internationale Wettbewerbsposition der deutschen Umweltschutzwirtschaft

Energy Technology Data Exchange (ETDEWEB)

Legler, Harald; Schasse, Ulrich [Niedersaechsisches Institut fuer Wirtschaftsforschung e.V., Hannover (Germany)

2009-06-15

There exists a connection between the economic structural orientation and international competitiveness on the one hand as well as the environmental political requirements on the other hand. The environmental protection economy fits quite well the profile that Germany is demanded in the international change. Under this aspect, the authors of the contribution under consideration report on the production structure and on the international competition position of the German environmental protection economy. The authors report on (a) the production structure and production dynamics of the environmental protection industry; (b) German environmental protection economy in the international comparison; (c) Goods, building works and services for environmental protection in Germany.

Effect of the kind of alkaline and rare earth ions on the structure of a glass rich in earth

International Nuclear Information System (INIS)

Quintas, Arnaud; Caurant, Daniel; Majerus, Odile; Lenoir, Marion; Dussossoy, Jean-Luc; Charpentier, Thibault; Neuville, Daniel R.; Gervais, C.

2006-01-01

In the framework of a structural study of a nuclear wastes containment glass of type alumino borosilicate and rich in rare earths, the influence of the kind of alkaline or rare earth ions is analyzed. For that, two glasses series have been prepared in which the Na + ion (respectively Ca 2+ ions) present in the standard composition is totally substituted by another alkaline ion Li + , K + , Rb + or Cs + (respectively another rare earth ion Mg 2+ , Sr 2+ or Ba 2+ ). These glasses, analyzed by optical absorption, Raman and 27 Al or 11 B NMR spectroscopies have revealed the strong impact of the kind of the modifying ion as well as the structure of the vitreous lattice (variation of the ratio BO 3 /BO 4 and local variations of the polymerization degree) than the local surroundings of the rare earth (decrease of the covalency degree of the bond Nd-O with the increase of the field force of the modifying ion). (O.M.)

Mapping and predictive variations of soil bacterial richness across France.

Science.gov (United States)

Terrat, Sébastien; Horrigue, Walid; Dequiedt, Samuel; Saby, Nicolas P A; Lelièvre, Mélanie; Nowak, Virginie; Tripied, Julie; Régnier, Tiffanie; Jolivet, Claudy; Arrouays, Dominique; Wincker, Patrick; Cruaud, Corinne; Karimi, Battle; Bispo, Antonio; Maron, Pierre Alain; Chemidlin Prévost-Bouré, Nicolas; Ranjard, Lionel

2017-01-01

Although numerous studies have demonstrated the key role of bacterial diversity in soil functions and ecosystem services, little is known about the variations and determinants of such diversity on a nationwide scale. The overall objectives of this study were i) to describe the bacterial taxonomic richness variations across France, ii) to identify the ecological processes (i.e. selection by the environment and dispersal limitation) influencing this distribution, and iii) to develop a statistical predictive model of soil bacterial richness. We used the French Soil Quality Monitoring Network (RMQS), which covers all of France with 2,173 sites. The soil bacterial richness (i.e. OTU number) was determined by pyrosequencing 16S rRNA genes and related to the soil characteristics, climatic conditions, geomorphology, land use and space. Mapping of bacterial richness revealed a heterogeneous spatial distribution, structured into patches of about 111km, where the main drivers were the soil physico-chemical properties (18% of explained variance), the spatial descriptors (5.25%, 1.89% and 1.02% for the fine, medium and coarse scales, respectively), and the land use (1.4%). Based on these drivers, a predictive model was developed, which allows a good prediction of the bacterial richness (R2adj of 0.56) and provides a reference value for a given pedoclimatic condition.

Influence Of The Neutron Richness On Binary Decays

Directory of Open Access Journals (Sweden)

Roy R.

2010-03-01

Full Text Available The influence of the neutron richness on binary decays is investigated in 78,82Kr+ 40Ca reactions at 5.5 MeV/A incident energy. Kinetic energy distributions and angular distributions of fragments with atomic number 6 ≤ Z ≤ 28 were measured using the 4π-INDRA array. Global features are compatible with an emission from a long-lived system. The yields around the symmetric splitting are about 30The persistence of strong structural effects is evidenced from elemental cross-sections of the light fragments. The cross-sections for odd-Z fragments are higher for the neutron rich CN while cross-sections for even-Z fragments are higher for the neutron poor CN. Calculations assuming two different potential energy surfaces are presented.

Numerical modelling of continuous spin detonation in rich methane-oxygen mixture

International Nuclear Information System (INIS)

Trotsyuk, A V

2016-01-01

A numerical simulation of a two-dimensional structure of the detonation wave (DW) in a rich (equivalence ratio φ=1.5) methane-air mixture at normal initial condition has been conducted. The computations have been performed in a wide range of channel heights. From the analysis of the flow structure and the number of primary transverse waves in the channel, the dominant size of the detonation cell for studied mixture has been determined to be 45÷50 cm. Based on the fundamental studies of multi-front (cellular) structure of the classical propagating DW in methane mixtures, numerical simulation of continuous spin detonation (CSD) of rich (φ=1.2) methane-oxygen mixture has been carried out in the cylindrical detonation chamber (DC) of the rocket-type engine. We studied the global flow structure in DC, and the detailed structure of the front of the rotating DW. Integral characteristics of the detonation process - the distribution of average values of static and total pressure along the length of the DC, and the value of specific impulse have been obtained. The geometric limit of stable existence of CSD has been determined. (paper)

Structural Empowerment and Organizational Commitment of Lecturers in Private International Educational Institutions at Thailand

Science.gov (United States)

Puncreobutr, Vichian

2016-01-01

The purpose of this research was to measure the level of structural empowerment and organizational commitment of lecturers at private international educational institutions at Thailand. Further to measure the relationship between structural empowerment and organizational commitment of lecturers. The target respondents of the study were lecturers…

Effect of carbo-nitride-rich and oxide-rich inclusions on the pitting susceptibility of depleted uranium

International Nuclear Information System (INIS)

Pu, Zhen; Chen, Xianglin; Meng, Xiandong; Wu, Yanping; Shen, Liang; Wang, Qingfu; Liu, Tianwei; Shuai, Maobing

2017-01-01

Highlights: •The Volta potential differences relative to the matrix are positive for both types of inclusions. •Both types of inclusions are cathodic in the “inclusion/matrix” microgalvanic couples. •The oxide-rich inclusions show a larger Volta potential value of about 115 mV than the carbo-nitride-rich inclusions. •The oxide-rich inclusions give stronger local galvanic coupling with the matrix. •The oxide-rich inclusions are more predisposed to initiate pitting corrosion. -- Abstract: The effects of carbo-nitride-rich and oxide-rich inclusions on the pitting susceptibility of depleted uranium were investigated by electrochemical corrosion measurements, optical microscopy, scanning Kelvin probe force microscopy (SKPFM), and SEM. The results of the potentiodynamic polarization tests suggest that oxide-rich inclusions are more likely to induce pitting corrosion than carbo-nitride-rich inclusions. This enhanced corrosion may be explained by the strong local galvanic coupling between the oxide-rich inclusion and the surrounding matrix, which, from the sight of SKPFM analysis, exhibits a 115 V higher Volta potential than the coupling between the carbo-nitride-rich inclusions and the matrix, respectively.

Swimming clusters in thallium-rich liquid caesium-thallium alloys

NARCIS (Netherlands)

van der Aart, SA; van der Lugt, W; Badyal, YS; Verkerk, P

The purpose of the work presented here is to obtain structural information on thallium-rich caesium-thallium alloys by means of neutron diffraction. The alloys exhibit a long-range (>1 nm) superstructure. This range increases with the thallium content. The results are interpreted with the help of a

Mapping Optimal Charge Density and Length of ROMP-Based PTDMs for siRNA Internalization.

Science.gov (United States)

Caffrey, Leah M; deRonde, Brittany M; Minter, Lisa M; Tew, Gregory N

2016-10-10

A fundamental understanding of how polymer structure impacts internalization and delivery of biologically relevant cargoes, particularly small interfering ribonucleic acid (siRNA), is of critical importance to the successful design of improved delivery reagents. Herein we report the use of ring-opening metathesis polymerization (ROMP) methods to synthesize two series of guanidinium-rich protein transduction domain mimics (PTDMs): one based on an imide scaffold that contains one guanidinium moiety per repeat unit, and another based on a diester scaffold that contains two guanidinium moieties per repeat unit. By varying both the degree of polymerization and, in effect, the relative number of cationic charges in each PTDM, the performances of the two ROMP backbones for siRNA internalization were evaluated and compared. Internalization of fluorescently labeled siRNA into Jurkat T cells demonstrated that fluorescein isothiocyanate (FITC)-siRNA internalization had a charge content dependence, with PTDMs containing approximately 40 to 60 cationic charges facilitating the most internalization. Despite this charge content dependence, the imide scaffold yielded much lower viabilities in Jurkat T cells than the corresponding diester PTDMs with similar numbers of cationic charges, suggesting that the diester scaffold is preferred for siRNA internalization and delivery applications. These developments will not only improve our understanding of the structural factors necessary for optimal siRNA internalization, but will also guide the future development of optimized PTDMs for siRNA internalization and delivery.

Protein Phosphorylation and Mineral Binding Affect the Secondary Structure of the Leucine-Rich Amelogenin Peptide

Directory of Open Access Journals (Sweden)

Hajime Yamazaki

2017-06-01

Full Text Available Previously, we have shown that serine-16 phosphorylation in native full-length porcine amelogenin (P173 and the Leucine-Rich Amelogenin Peptide (LRAP(+P, an alternative amelogenin splice product, affects protein assembly and mineralization in vitro. Notably, P173 and LRAP(+P stabilize amorphous calcium phosphate (ACP and inhibit hydroxyapatite (HA formation, while non-phosphorylated counterparts (rP172, LRAP(−P guide the growth of ordered bundles of HA crystals. Based on these findings, we hypothesize that the phosphorylation of full-length amelogenin and LRAP induces conformational changes that critically affect its capacity to interact with forming calcium phosphate mineral phases. To test this hypothesis, we have utilized Fourier transform infrared spectroscopy (FTIR to determine the secondary structure of LRAP(−P and LRAP(+P in the absence/presence of calcium and selected mineral phases relevant to amelogenesis; i.e., hydroxyapatite (HA: an enamel crystal prototype and (ACP: an enamel crystal precursor phase. Aqueous solutions of LRAP(−P or LRAP(+P were prepared with or without 7.5 mM of CaCl2 at pH 7.4. FTIR spectra of each solution were obtained using attenuated total reflectance, and amide-I peaks were analyzed to provide secondary structure information. Secondary structures of LRAP(+P and LRAP(−P were similarly assessed following incubation with suspensions of HA and pyrophosphate-stabilized ACP. Amide I spectra of LRAP(−P and LRAP(+P were found to be distinct from each other in all cases. Spectra analyses showed that LRAP(−P is comprised mostly of random coil and β-sheet, while LRAP(+P exhibits more β-sheet and α-helix with little random coil. With added Ca, the random coil content increased in LRAP(−P, while LRAP(+P exhibited a decrease in α-helix components. Incubation of LRAP(−P with HA or ACP resulted in comparable increases in β-sheet structure. Notably, however, LRAP(+P secondary structure was more affected by

4th International Conference on Structural Nonlinear Dynamics and Diagnosis

CERN Document Server

2018-01-01

This book presents contributions on the most active lines of recent advanced research in the field of nonlinear mechanics and physics selected from the 4th International Conference on Structural Nonlinear Dynamics and Diagnosis. It includes fifteen chapters by outstanding scientists, covering various aspects of applications, including road tanker dynamics and stability, simulation of abrasive wear, energy harvesting, modeling and analysis of flexoelectric nanoactuator, periodic Fermi–Pasta–Ulam problems, nonlinear stability in Hamiltonian systems, nonlinear dynamics of rotating composites, nonlinear vibrations of a shallow arch, extreme pulse dynamics in mode-locked lasers, localized structures in a photonic crystal fiber resonator, nonlinear stochastic dynamics, linearization of nonlinear resonances, treatment of a linear delay differential equation, and fractional nonlinear damping. It appeals to a wide range of experts in the field of structural nonlinear dynamics and offers researchers and engineers a...

Spatial variability of microbial richness and diversity and relationships with soil organic carbon, texture and structure across an agricultural field

DEFF Research Database (Denmark)

Naveed, Muhammad; Herath, Lasantha; Møldrup, Per

2016-01-01

Highlights •Bacterial richness and Shannon diversity showed strong spatial autocorrelations. •Fungal richness and Shannon diversity did not show any clear spatial autocorrelations. •Ratio of clay to organic carbon was found a best predictor of bacterial richness and diversities. •Soil water...

Proton-rich nuclear statistical equilibrium

International Nuclear Information System (INIS)

Seitenzahl, I.R.; Timmes, F.X.; Marin-Lafleche, A.; Brown, E.; Magkotsios, G.; Truran, J.

2008-01-01

Proton-rich material in a state of nuclear statistical equilibrium (NSE) is one of the least studied regimes of nucleosynthesis. One reason for this is that after hydrogen burning, stellar evolution proceeds at conditions of an equal number of neutrons and protons or at a slight degree of neutron-richness. Proton-rich nucleosynthesis in stars tends to occur only when hydrogen-rich material that accretes onto a white dwarf or a neutron star explodes, or when neutrino interactions in the winds from a nascent proto-neutron star or collapsar disk drive the matter proton-rich prior to or during the nucleosynthesis. In this Letter we solve the NSE equations for a range of proton-rich thermodynamic conditions. We show that cold proton-rich NSE is qualitatively different from neutron-rich NSE. Instead of being dominated by the Fe-peak nuclei with the largest binding energy per nucleon that have a proton-to-nucleon ratio close to the prescribed electron fraction, NSE for proton-rich material near freezeout temperature is mainly composed of 56Ni and free protons. Previous results of nuclear reaction network calculations rely on this nonintuitive high-proton abundance, which this Letter explains. We show how the differences and especially the large fraction of free protons arises from the minimization of the free energy as a result of a delicate competition between the entropy and nuclear binding energy.

Influence of electron irradiation on internal friction and structure evolution of polymer composites

International Nuclear Information System (INIS)

Ismailova, G.A.

2007-01-01

Full text: Important qualitative information on structural evolution and radiation alterations in polymer materials under the action of ionizing radiation can be obtained from the analysis of the temperature dependences of internal friction. Changing of internal friction parameters of relax maxima during irradiation is qualitative degree parameter of radiation scission-cross linking of the polymer molecules. In this work, the general phenomenological approach is realized by introduction of the effective 'observed' parameters into the simple kinetic equations. The applicability of such approach is justified by the fact that kinetics of both internal friction and scission-cross linking processes can be characterized by the same effective parameters. Temperature dependences of internal friction are experimentally studied in epoxy irradiated by 2.5 MeV pulse electron beam to different doses (D=3 MGy, 6 MGy and 9 MGy). Time dependences of internal friction characteristics associated with radiation-induced processes of polymer scission and cross-linking are analyzed and discussed. Experimental data on kinetics of structural transformations in epoxy are interpreted on the base of analytical solutions of differential equations for free radical accumulation during and after irradiation subject to the arbitrary effective order of radical recombination. It is shown that in the range of doses and dose rates under study radiation-induced scission predominates during polymer irradiation but in a certain period of time after irradiation scission changes to cross-linking. Characteristics of the kinetic curves obtained essentially depend on the dose

Internal Grammar and Children's Grammatical Creativity against Poor Inputs

Directory of Open Access Journals (Sweden)

Adriana Belletti

2017-12-01

Full Text Available This article is about the unexpected linguistic behavior that young children sometimes display by producing structures that are only marginally present in the adult language in a constrained way, and that adults do not adopt in the same experimental conditions. It is argued here that children's capacity to overextend the use of given syntactic structures thereby resulting in a grammatical creative behavior is the sign of an internal grammatical pressure which manifests itself given appropriate discourse conditions and factors of grammatical complexity and which does not necessarily require a rich input to be put into work. This poverty of the stimulus type situation is illustrated here through the overextended use of a-Topics and reflexive-causative passives by young Italian speaking children when answering eliciting questions concerning the direct object of the clause.

Cherenkov angle and charge reconstruction with the RICH detector of the AMS experiment

CERN Document Server

Barão, F; Borges, J; Gonçalves, P; Pimenta, M; Pérez, I

2003-01-01

The Alpha Magnetic Spectrometer experiment to be installed on the International Space Station will be equipped with a proximity focusing Ring Imaging Cherenkov (RICH) detector, for measurements of particle electric charge and velocity. In this note, two possible methods for reconstructing the Cherenkov angle and the electric charge with the RICH are discussed. A Likelihood method for the Cherenkov angle reconstruction was applied leading to a velocity determination for protons with a resolution of around 0.1%. The existence of a large fraction of background photons which can vary from event to event implied a charge reconstruction method based on an overall efficiency estimation on an event-by-event basis.

3D reconstruction of internal structure of animal body using near-infrared light

Science.gov (United States)

Tran, Trung Nghia; Yamamoto, Kohei; Namita, Takeshi; Kato, Yuji; Shimizu, Koichi

2014-03-01

To realize three-dimensional (3D) optical imaging of the internal structure of animal body, we have developed a new technique to reconstruct CT images from two-dimensional (2D) transillumination images. In transillumination imaging, the image is blurred due to the strong scattering in the tissue. We had developed a scattering suppression technique using the point spread function (PSF) for a fluorescent light source in the body. In this study, we have newly proposed a technique to apply this PSF for a light source to the image of unknown light-absorbing structure. The effectiveness of the proposed technique was examined in the experiments with a model phantom and a mouse. In the phantom experiment, the absorbers were placed in the tissue-equivalent medium to simulate the light-absorbing organs in mouse body. Near-infrared light was illuminated from one side of the phantom and the image was recorded with CMOS camera from another side. Using the proposed techniques, the scattering effect was efficiently suppressed and the absorbing structure can be visualized in the 2D transillumination image. Using the 2D images obtained in many different orientations, we could reconstruct the 3D image. In the mouse experiment, an anesthetized mouse was held in an acrylic cylindrical holder. We can visualize the internal organs such as kidneys through mouse's abdomen using the proposed technique. The 3D image of the kidneys and a part of the liver were reconstructed. Through these experimental studies, the feasibility of practical 3D imaging of the internal light-absorbing structure of a small animal was verified.

Arginine-rich intracellular delivery peptides noncovalently transport protein into living cells

International Nuclear Information System (INIS)

Wang, Y.-H.; Chen, C.-P.; Chan, M.-H.; Chang, M.; Hou, Y.-W.; Chen, H.-H.; Hsu, H.-R.; Liu, Kevin; Lee, H.-J.

2006-01-01

Plasma membranes of plant or animal cells are generally impermeable to peptides or proteins. Many basic peptides have previously been investigated and covalently cross-linked with cargoes for cellular internalization. In the current study, we demonstrate that arginine-rich intracellular delivery (AID) peptides are able to deliver fluorescent proteins or β-galactosidase enzyme into animal and plant cells, as well as animal tissue. Cellular internalization and transdermal delivery of protein could be mediated by effective and nontoxic AID peptides in a neither fusion protein nor conjugation fashion. Therefore, noncovalent AID peptides may provide a useful strategy to have active proteins function in living cells and tissues in vivo

Digital literacy and problem solving in technology-rich environments

Directory of Open Access Journals (Sweden)

Vesna Dolničar

2015-07-01

Full Text Available Rapid development and progress, as well as the growing presence of information and communications technologies dictate the need for more highly developed digital skills in individuals. The paper focuses on the concepts of digital skills and problem solving in technology-rich environments. It examines these on the basis of empirical data obtained in the international study PIAAC. The introductory part presents an overview of the literature and the results of previous research in the field of measurement of digital skills, and data on the use of information society services among the EU Member States. The second part of the article refers to the results obtained in the study PIAAC. The results, confirmed by the results of other studies, showed the impact of age and education level on the problem solving in technology-rich environments. Article concludes with suggestions for improving the current state of integration of all population groups in training programs in the field of digital skills.

Structure of neutron rich nuclei of Germanium and Gallium beyond N equals 50 at Alto

International Nuclear Information System (INIS)

Lebois, M.

2008-09-01

The gamma rays following the beta decay of the following very neutron-rich isotopes: 82,83,84 Ga produced by photo-fission, have been studied at the newly built ISOL facility in Orsay: ALTO. In ALTO the interaction of an electron beam with U 238 target generates a continuous spectra of Bremsstrahlung gamma radiation that triggers U 238 fission. The fission fragments are then ionized, extracted and mass-separated. The analysis of the data has shown the existence of an isomer in 31 84 Ga 53 and has enabled us to confirm known results on 32 83 Ge 51 energy levels including the gamma transition between the 1/2+ state at 247,7 KeV and the fundamental state. We have also proposed the first energy level scheme for 33 84 As 51 . In order to understand the structure of the nucleus we have used the Thankappan and True model that gives a description of the coupling between the pair-pair core (half-magical) and the single nucleon. This model applied to the N=51 chain ( 38 89 Sr 51 , 36 87 Kr 51 , 34 85 Se 51 , 32 83 Ge 51 and 30 81 Zn 51 ) has allowed us to see the main features of odd isotope structure. We have also confirmed previous results concerning the nature of the states in the following decay 31 83 Ga 52 → 32 83 Ge 51

Reactions with fast radioactive beams of neutron-rich nuclei

Energy Technology Data Exchange (ETDEWEB)

Aumann, T. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)

2005-11-01

The neutron dripline has presently been reached only for the lightest nuclei up to the element oxygen. In this region of light neutron-rich nuclei, scattering experiments are feasible even for dripline nuclei by utilizing high-energy secondary beams produced by fragmentation. In the present article, reactions of high-energy radioactive beams will be exemplified using recent experimental results mainly derived from measurements of breakup reactions performed at the LAND and FRS facilities at GSI and at the S800 spectrometer at the NSCL. Nuclear and electromagnetically induced reactions allow probing different aspects of nuclear structure at the limits of stability related to the neutron-proton asymmetry and the weak binding close to the dripline. Properties of the valence-neutron wave functions are studied in the one-neutron knockout reaction, revealing the changes of shell structure when going from the beta-stability line to more asymmetric loosely bound neutron-rich systems. The vanishing of the N=8 shell gap for neutron-rich systems like {sup 11}Li and {sup 12}Be, or the new closed N=14, 16 shells for the oxygen isotopes are examples. The continuum of weakly bound nuclei and halo states can be studied by inelastic scattering. The dipole response, for instance, is found to change dramatically when going away from the valley of stability. A redistribution of the dipole strength towards lower excitation energies is observed for neutron-rich nuclei, which partly might be due to a new collective excitation mode related to the neutron-proton asymmetry. Halo nuclei in particular show strong dipole transitions to the continuum at the threshold, being directly related to the ground-state properties of the projectile. Finally, an outlook on future experimental prospects is given. (orig.)

Reactions with fast radioactive beams of neutron-rich nuclei

International Nuclear Information System (INIS)

Aumann, T.

2005-11-01

The neutron dripline has presently been reached only for the lightest nuclei up to the element oxygen. In this region of light neutron-rich nuclei, scattering experiments are feasible even for dripline nuclei by utilizing high-energy secondary beams produced by fragmentation. In the present article, reactions of high-energy radioactive beams will be exemplified using recent experimental results mainly derived from measurements of breakup reactions performed at the LAND and FRS facilities at GSI and at the S800 spectrometer at the NSCL. Nuclear and electromagnetically induced reactions allow probing different aspects of nuclear structure at the limits of stability related to the neutron-proton asymmetry and the weak binding close to the dripline. Properties of the valence-neutron wave functions are studied in the one-neutron knockout reaction, revealing the changes of shell structure when going from the beta-stability line to more asymmetric loosely bound neutron-rich systems. The vanishing of the N=8 shell gap for neutron-rich systems like 11 Li and 12 Be, or the new closed N=14, 16 shells for the oxygen isotopes are examples. The continuum of weakly bound nuclei and halo states can be studied by inelastic scattering. The dipole response, for instance, is found to change dramatically when going away from the valley of stability. A redistribution of the dipole strength towards lower excitation energies is observed for neutron-rich nuclei, which partly might be due to a new collective excitation mode related to the neutron-proton asymmetry. Halo nuclei in particular show strong dipole transitions to the continuum at the threshold, being directly related to the ground-state properties of the projectile. Finally, an outlook on future experimental prospects is given. (orig.)

Fast flexible modeling of RNA structure using internal coordinates.

Science.gov (United States)

Flores, Samuel Coulbourn; Sherman, Michael A; Bruns, Christopher M; Eastman, Peter; Altman, Russ Biagio

2011-01-01

Modeling the structure and dynamics of large macromolecules remains a critical challenge. Molecular dynamics (MD) simulations are expensive because they model every atom independently, and are difficult to combine with experimentally derived knowledge. Assembly of molecules using fragments from libraries relies on the database of known structures and thus may not work for novel motifs. Coarse-grained modeling methods have yielded good results on large molecules but can suffer from difficulties in creating more detailed full atomic realizations. There is therefore a need for molecular modeling algorithms that remain chemically accurate and economical for large molecules, do not rely on fragment libraries, and can incorporate experimental information. RNABuilder works in the internal coordinate space of dihedral angles and thus has time requirements proportional to the number of moving parts rather than the number of atoms. It provides accurate physics-based response to applied forces, but also allows user-specified forces for incorporating experimental information. A particular strength of RNABuilder is that all Leontis-Westhof basepairs can be specified as primitives by the user to be satisfied during model construction. We apply RNABuilder to predict the structure of an RNA molecule with 160 bases from its secondary structure, as well as experimental information. Our model matches the known structure to 10.2 Angstroms RMSD and has low computational expense.

Platelet-rich plasma in otolaryngology.

Science.gov (United States)

Stavrakas, M; Karkos, P D; Markou, K; Grigoriadis, N

2016-12-01

Platelet-rich plasma is a novel material that is being used more frequently in many surgical specialties. A literature review on the current and potential uses of platelet-rich plasma in otolaryngology was performed. There is limited evidence on the use of platelet-rich plasma in otolaryngology compared with other specialties: only 11 studies on various subspecialties (otology, rhinology and laryngology) were included in the final review. Based on the limited number of studies, we cannot draw safe conclusions about the value of platelet-rich plasma in otolaryngology. Nevertheless, the available literature suggests that platelet-rich plasma holds promise for future research and may have a number of clinical applications.

Generalized internal long wave equations: construction, hamiltonian structure and conservation laws

International Nuclear Information System (INIS)

Lebedev, D.R.

1982-01-01

Some aspects of the theory of the internal long-wave equations (ILW) are considered. A general class of the ILW type equations is constructed by means of the Zakharov-Shabat ''dressing'' method. Hamiltonian structure and infinite numbers of conservation laws are introduced. The considered equations are shown to be Hamiltonian in the so-called second Hamiltonian structu

High-resolution crystal structure of Streptococcus pyogenes β-NAD{sup +} glycohydrolase in complex with its endogenous inhibitor IFS reveals a highly water-rich interface

Energy Technology Data Exchange (ETDEWEB)

Yoon, Ji Young; An, Doo Ri; Yoon, Hye-Jin [Seoul National University, Seoul 151-747 (Korea, Republic of); Kim, Hyoun Sook [Seoul National University, Seoul 151-747 (Korea, Republic of); Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, Sang Jae [Seoul National University, Seoul 151-742 (Korea, Republic of); Im, Ha Na; Jang, Jun Young [Seoul National University, Seoul 151-747 (Korea, Republic of); Suh, Se Won, E-mail: sewonsuh@snu.ac.kr [Seoul National University, Seoul 151-747 (Korea, Republic of); Seoul National University, Seoul 151-747 (Korea, Republic of)

2013-11-01

The crystal structure of the complex between the C-terminal domain of Streptococcus pyogenes β-NAD{sup +} glycohydrolase and an endogenous inhibitor for SPN was determined at 1.70 Å. It reveals that the interface between the two proteins is highly rich in water molecules. One of the virulence factors produced by Streptococcus pyogenes is β-NAD{sup +} glycohydrolase (SPN). S. pyogenes injects SPN into the cytosol of an infected host cell using the cytolysin-mediated translocation pathway. As SPN is toxic to bacterial cells themselves, S. pyogenes possesses the ifs gene that encodes an endogenous inhibitor for SPN (IFS). IFS is localized intracellularly and forms a complex with SPN. This intracellular complex must be dissociated during export through the cell envelope. To provide a structural basis for understanding the interactions between SPN and IFS, the complex was overexpressed between the mature SPN (residues 38–451) and the full-length IFS (residues 1–161), but it could not be crystallized. Therefore, limited proteolysis was used to isolate a crystallizable SPN{sub ct}–IFS complex, which consists of the SPN C-terminal domain (SPN{sub ct}; residues 193–451) and the full-length IFS. Its crystal structure has been determined by single anomalous diffraction and the model refined at 1.70 Å resolution. Interestingly, our high-resolution structure of the complex reveals that the interface between SPN{sub ct} and IFS is highly rich in water molecules and many of the interactions are water-mediated. The wet interface may facilitate the dissociation of the complex for translocation across the cell envelope.

Myotonic Dystrophy Type 1 RNA Crystal Structures Reveal Heterogeneous 1 × 1 Nucleotide UU Internal Loop Conformations

Energy Technology Data Exchange (ETDEWEB)

Kumar, Amit; Park, HaJeung; Fang, Pengfei; Parkesh, Raman; Guo, Min; Nettles, Kendall W.; Disney, Matthew D. (Scripps)

2012-03-27

RNA internal loops often display a variety of conformations in solution. Herein, we visualize conformational heterogeneity in the context of the 5'CUG/3'GUC repeat motif present in the RNA that causes myotonic dystrophy type 1 (DM1). Specifically, two crystal structures of a model DM1 triplet repeating construct, 5'r[{und UU}GGGC(C{und U}G){sub 3}GUCC]{sub 2}, refined to 2.20 and 1.52 {angstrom} resolution are disclosed. Here, differences in the orientation of the 5' dangling UU end between the two structures induce changes in the backbone groove width, which reveals that noncanonical 1 x 1 nucleotide UU internal loops can display an ensemble of pairing conformations. In the 2.20 {angstrom} structure, CUGa, the 5' UU forms a one hydrogen-bonded pair with a 5' UU of a neighboring helix in the unit cell to form a pseudoinfinite helix. The central 1 x 1 nucleotide UU internal loop has no hydrogen bonds, while the terminal 1 x 1 nucleotide UU internal loops each form a one-hydrogen bond pair. In the 1.52 {angstrom} structure, CUGb, the 5' UU dangling end is tucked into the major groove of the duplex. While the canonically paired bases show no change in base pairing, in CUGb the terminal 1 x 1 nucleotide UU internal loops now form two hydrogen-bonded pairs. Thus, the shift in the major groove induced by the 5' UU dangling end alters noncanonical base patterns. Collectively, these structures indicate that 1 x 1 nucleotide UU internal loops in DM1 may sample multiple conformations in vivo. This observation has implications for the recognition of this RNA, and other repeating transcripts, by protein and small molecule ligands.

Vaccatides: Antifungal Glutamine-Rich Hevein-Like Peptides from Vaccaria hispanica

Directory of Open Access Journals (Sweden)

Ka H. Wong

2017-06-01

Full Text Available Hevein and hevein-like peptides are disulfide-constrained chitin-binding cysteine-rich peptides. They are divided into three subfamilies, 6C-, 8C-, and 10C-hevein-like peptides, based on the number of cysteine residues. In addition, hevein-like peptides can exist in two forms, short and long. The long C-terminal form found in hevein and 10C-hevein-like peptides contain a C-terminal protein cargo. In contrast, the short form without a protein cargo is found in all three subfamilies. Here, we report the discovery and characterization of two novel glutamine-rich and protein cargo-free 8C-hevein-like peptides, vaccatides vH1 and vH2, from Vaccaria hispanica of the Caryophyllaceae family. Proteomic analyses showed that the vaccatides are 40–41 amino acids in length and contain a chitin-binding domain. NMR determination revealed that vaccatide vH2 displays a highly compact structure with a N-terminal cystine knot and an addition C-terminal disulfide bond. Stability studies showed that this compact structure renders vaccatide vH2 resistant to thermal, chemical and proteolytic degradation. The chitin-binding vH2 was shown to inhibit the mycelium growth of four phyto-pathogenic fungal strains with IC50 values in the micromolar range. Our findings show that vaccatides represent a new family of 8C-hevein-like peptides, which are protein cargo-free and glutamine-rich, characteristics that differentiate them from the prototypic hevein and the 10C-hevein-like peptides. In summary, this study enriches the existing library of hevein-like peptides and provides insight into their molecular diversity in sequence, structure and biosynthesis. Additionally, their highly disulfide-constrained structure could be used as a scaffold for developing metabolically and orally active peptidyl therapeutics.

Mammal predator and prey species richness are strongly linked at macroscales

DEFF Research Database (Denmark)

Sandom, Christopher James; Dalby, Lars; Fløjgaard, Camilla

2013-01-01

Predator–prey interactions play an important role for species composition and community dynamics at local scales, but their importance in shaping large-scale gradients of species richness remains unexplored. Here, we use global range maps, structural equation models (SEM), and comprehensive...... databases of dietary preferences and body masses of all terrestrial, non-volant mammals worldwide, to test whether (1) prey-bottom-up or predator- top-down relationships are important drivers of broad-scale species richness gradients once the environment and human influence has been accounted for, (2...... between them (e.g., large prey to small predators), suggesting that mass-related energetic and physiological constraints influence broad-scale richness links, especially for large-bodied mammals. Overall, our results support the idea that trophic interactions can be important drivers of large...

Tailoring of magnetoimpedance effect and magnetic softness of Fe-rich glass-coated microwires by stress- annealing.

Science.gov (United States)

Zhukova, V; Blanco, J M; Ipatov, M; Churyukanova, M; Taskaev, S; Zhukov, A

2018-02-16

There is a pressing need for improving of the high-frequency magneto-impedance effect of cost-effective soft magnetic materials for use in high-performance sensing devices. The impact of the stress-annealing on magnetic properties and high frequency impedance of Fe-rich glass-coated microwires was studied. Hysteresis loops of Fe-rich microwires have been considerably affected by stress- annealing. In stress-annealed Fe- rich microwire we obtained drastic decreasing of coercivity and change of character of hysteresis loop from rectangular to linear. By controlling stress-annealing conditions (temperature and time) we achieved drastic increasing (by order of magnitude) of giant magnetoimpedance ratio. Coercivity, remanent magnetization, diagonal and of-diagonal magnetoimpedance effect of Fe-rich microwires can be tuned by stress-annealing conditions: annealing temperature and time. Observed experimental results are discussed considering relaxation of internal stresses, compressive "back-stresses" arising after stress annealing and topological short range ordering.

Method for remote diagnostics of the internal structure of layered media

International Nuclear Information System (INIS)

Lychagov, V V; Kal'yanov, A L; Ryabukho, V P; Lyakin, D V

2008-01-01

The method of autocorrelation low coherence interferometry is proposed for diagnostics of inhomogeneities and the internal structure of layered technical and biological samples. In this method the low coherence optical field reflected from the layered sample is analysed by using a Michelson interferometer. Because the object is outside the interferometer, the distance between the interferometer and the object under study is not limited and thus the object can move during the measurements. Theoretical substantiation of the autocorrelation method for media with discrete and continuous optical structure modifications is presented. (special issue devoted to application of laser technologies in biophotonics and biomedical studies)

A design strategy of large grain lithium-rich layered oxides for lithium-ion batteries cathode

International Nuclear Information System (INIS)

Jiang, Xiong; Wang, Zhenhua; Rooney, David; Zhang, Xiaoxue; Feng, Jie; Qiao, Jinshuo; Sun, Wang; Sun, Kening

2015-01-01

Highlights: • Ultrasound-assisted mixing lithium was used to synthesize Lithium-rich layered oxides. • Lithium-rich layered oxides composed of large grain had high capacity and high cycling stability. • This unique large grain overcomes stress-induced structural collapse caused by Li-ion insertion/extraction and reduces dissolution of Mn ions. • A new strategy of large grain could be employed to synthesize the other complex architectures for various applications. - Abstract: Li-rich materials are considered the most promising for Li-ion battery cathodes, as high capacity can be achieved. However, poor cycling stability is a critical drawback that leads to poor capacity retention. Here a strategy is used to synthesize a large-grain lithium-rich layered oxides to overcome this difficulty without sacrificing rate capability. This material is designed with micron scale grain with a width of about 300 nm and length of 1–3 μm. This unique structure has a better ability to overcome stress-induced structural collapse caused by Li-ion insertion/extraction and reduce the dissolution of Mn ions, which enable a reversible and stable capacity. As a result, this cathode material delivered a highest discharge capacity of around 308 mAh g −1 at a current density of 30 mA g −1 with retention of 88.3% (according to the highest discharge capacity) after 100 cycles, 190 mAh g −1 at a current density of 300 mA g −1 and almost no capacity fading after 100 cycles. Therefore, Lithium-rich material of large-grain structure is a promising cathode candidate in Lithium-ion batteries with high capacity and high cycle stability for application. This strategy of large grain may furthermore open the door to synthesize the other complex architectures for various applications

Use of rich-media resources by engineering undergraduates

Science.gov (United States)

Gillie, Martin; Dahli, Ranim; Saunders, Fiona C.; Gibson, Andrew

2017-11-01

The ability to develop and distribute digital teaching resources in higher education has developed rapidly over the last decade but research into how students use such resources has received limited attention. This study uses questionnaire results, Internet analytic data and semi-structured interviews to examine the use of three types of rich-media teaching resources - lecture podcasts, key-concept videos and tutorial solution videos - by engineering undergraduates. It is found that students value all three types of resource, especially for revision and as a supplement to lectures. Students find short, focused resources more useful than longer ones. Non-native English speakers and those with disabilities derive particular benefits from the resources. The effect of rich-media resources on lecture attendance is found to be small, and two-way.

COMPASS mirror wall of RICH 1

CERN Multimedia

Patrice Loïez

2001-01-01

The COMPASS experiment uses ring imaging Cherenkov (RICH) counters to identify particles produced in high-energy muon collisions, to better understand the spin structure of the nucleon. Charged particles moving faster than the speed of light in the medium through which they are travelling emit a cone of Cherenkov radiation in the direction of their motion. The light in this cone is reflected from these mirrors onto a photo detector so that the size of the cone can be measured, which gives the energy of the particle.

Pollen structure visualization using high-resolution laboratory-based hard X-ray tomography.

Science.gov (United States)

Li, Qiong; Gluch, Jürgen; Krüger, Peter; Gall, Martin; Neinhuis, Christoph; Zschech, Ehrenfried

2016-10-14

A laboratory-based X-ray microscope is used to investigate the 3D structure of unstained whole pollen grains. For the first time, high-resolution laboratory-based hard X-ray microscopy is applied to study pollen grains. Based on the efficient acquisition of statistically relevant information-rich images using Zernike phase contrast, both surface- and internal structures of pine pollen - including exine, intine and cellular structures - are clearly visualized. The specific volumes of these structures are calculated from the tomographic data. The systematic three-dimensional study of pollen grains provides morphological and structural information about taxonomic characters that are essential in palynology. Such studies have a direct impact on disciplines such as forestry, agriculture, horticulture, plant breeding and biodiversity. Copyright © 2016 Elsevier Inc. All rights reserved.

Structural integrity and management of aging in internal components of BWR reactors

International Nuclear Information System (INIS)

Arganis J, C.R.

2004-01-01

Presently work the bases to apply structural integrity and the handling of the aging of internal components of the pressure vessel of boiling water reactors of water are revised and is carried out an example of structural integrity in the horizontal welding H4 of the encircling one of the core of a reactor, taking data reported in the literature. It is also revised what is required to carry out the handling program or conduct of the aging (AMP). (Author)

Influence of Sampling Effort on the Estimated Richness of Road-Killed Vertebrate Wildlife

Science.gov (United States)

Bager, Alex; da Rosa, Clarissa A.

2011-05-01

Road-killed mammals, birds, and reptiles were collected weekly from highways in southern Brazil in 2002 and 2005. The objective was to assess variation in estimates of road-kill impacts on species richness produced by different sampling efforts, and to provide information to aid in the experimental design of future sampling. Richness observed in weekly samples was compared with sampling for different periods. In each period, the list of road-killed species was evaluated based on estimates the community structure derived from weekly samplings, and by the presence of the ten species most subject to road mortality, and also of threatened species. Weekly samples were sufficient only for reptiles and mammals, considered separately. Richness estimated from the biweekly samples was equal to that found in the weekly samples, and gave satisfactory results for sampling the most abundant and threatened species. The ten most affected species showed constant road-mortality rates, independent of sampling interval, and also maintained their dominance structure. Birds required greater sampling effort. When the composition of road-killed species varies seasonally, it is necessary to take biweekly samples for a minimum of one year. Weekly or more-frequent sampling for periods longer than two years is necessary to provide a reliable estimate of total species richness.

Mapping and predictive variations of soil bacterial richness across France.

Directory of Open Access Journals (Sweden)

Sébastien Terrat

Full Text Available Although numerous studies have demonstrated the key role of bacterial diversity in soil functions and ecosystem services, little is known about the variations and determinants of such diversity on a nationwide scale. The overall objectives of this study were i to describe the bacterial taxonomic richness variations across France, ii to identify the ecological processes (i.e. selection by the environment and dispersal limitation influencing this distribution, and iii to develop a statistical predictive model of soil bacterial richness. We used the French Soil Quality Monitoring Network (RMQS, which covers all of France with 2,173 sites. The soil bacterial richness (i.e. OTU number was determined by pyrosequencing 16S rRNA genes and related to the soil characteristics, climatic conditions, geomorphology, land use and space. Mapping of bacterial richness revealed a heterogeneous spatial distribution, structured into patches of about 111km, where the main drivers were the soil physico-chemical properties (18% of explained variance, the spatial descriptors (5.25%, 1.89% and 1.02% for the fine, medium and coarse scales, respectively, and the land use (1.4%. Based on these drivers, a predictive model was developed, which allows a good prediction of the bacterial richness (R2adj of 0.56 and provides a reference value for a given pedoclimatic condition.

Development and Structure of Internal Glands and External Glandular Trichomes in Pogostemon cablin

Science.gov (United States)

Guo, Jiansheng; Yuan, Yongming; Liu, Zhixue; Zhu, Jian

2013-01-01

Pogostemon cablin possesses two morphologically and ontogenetically different types of glandular trichomes, one type of bristle hair on the surfaces of leaves and stems and one type of internal gland inside the leaves and stems. The internal gland originates from elementary meristem and is associated with the biosynthesis of oils present inside the leaves and stems. However, there is little information on mechanism for the oil biosynthesis and secretion inside the leaves and stems. In this study, we identified three kinds of glandular trichome types and two kinds of internal gland in the Pogostemon cablin. The oil secretions from internal glands of stems and leaves contained lipids, flavones and terpenes. Our results indicated that endoplasmic reticulum and plastids and vacuoles are likely involved in the biosynthesis of oils in the internal glands and the synthesized oils are transported from endoplasmic reticulum to the cell wall via connecting endoplasmic reticulum membranes to the plasma membrane. And the comparative analysis of the development, distribution, histochemistry and ultrastructures of the internal and external glands in Pogostemon cablin leads us to propose that the internal gland may be a novel secretory structure which is different from external glands. PMID:24205002

IOP Shape coexistence in neutron-rich strontium isotopes at N = 60

CERN Document Server

Clément, Emmanuel

2017-01-01

The structure of neutron-rich $^{96,98}$ Sr nuclei was investigated by low-energy Coulomb excitation of radioactive beams at the REX-ISOLDE facility, CERN, with the MINIBALL spectrometer. A rich set of transitional and diagonal E2 matrix elements has been extracted from the differential Coulomb-excitation cross sections. The results support the scenario of a shape transition at N=60, giving rise to the coexistence of a highly deformed prolate and a spherical configuration in $^{98}$ Sr with low configuration mixing.

A Sequence-Independent, Unstructured Internal Ribosome Entry Site Is Responsible for Internal Expression of the Coat Protein of Turnip Crinkle Virus.

Science.gov (United States)

May, Jared; Johnson, Philip; Saleem, Huma; Simon, Anne E

2017-04-15

To maximize the coding potential of viral genomes, internal ribosome entry sites (IRES) can be used to bypass the traditional requirement of a 5' cap and some/all of the associated translation initiation factors. Although viral IRES typically contain higher-order RNA structure, an unstructured sequence of about 84 nucleotides (nt) immediately upstream of the Turnip crinkle virus (TCV) coat protein (CP) open reading frame (ORF) has been found to promote internal expression of the CP from the genomic RNA (gRNA) both in vitro and in vivo An absence of extensive RNA structure was predicted using RNA folding algorithms and confirmed by selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) RNA structure probing. Analysis of the IRES region in vitro by use of both the TCV gRNA and reporter constructs did not reveal any sequence-specific elements but rather suggested that an overall lack of structure was an important feature for IRES activity. The CP IRES is A-rich, independent of orientation, and strongly conserved among viruses in the same genus. The IRES was dependent on eIF4G, but not eIF4E, for activity. Low levels of CP accumulated in vivo in the absence of detectable TCV subgenomic RNAs, strongly suggesting that the IRES was active in the gRNA in vivo Since the TCV CP also serves as the viral silencing suppressor, early translation of the CP from the viral gRNA is likely important for countering host defenses. Cellular mRNA IRES also lack extensive RNA structures or sequence conservation, suggesting that this viral IRES and cellular IRES may have similar strategies for internal translation initiation. IMPORTANCE Cap-independent translation is a common strategy among positive-sense, single-stranded RNA viruses for bypassing the host cell requirement of a 5' cap structure. Viral IRES, in general, contain extensive secondary structure that is critical for activity. In contrast, we demonstrate that a region of viral RNA devoid of extensive secondary

An Improved Cluster Richness Estimator

Energy Technology Data Exchange (ETDEWEB)

Rozo, Eduardo; /Ohio State U.; Rykoff, Eli S.; /UC, Santa Barbara; Koester, Benjamin P.; /Chicago U. /KICP, Chicago; McKay, Timothy; /Michigan U.; Hao, Jiangang; /Michigan U.; Evrard, August; /Michigan U.; Wechsler, Risa H.; /SLAC; Hansen, Sarah; /Chicago U. /KICP, Chicago; Sheldon, Erin; /New York U.; Johnston, David; /Houston U.; Becker, Matthew R.; /Chicago U. /KICP, Chicago; Annis, James T.; /Fermilab; Bleem, Lindsey; /Chicago U.; Scranton, Ryan; /Pittsburgh U.

2009-08-03

Minimizing the scatter between cluster mass and accessible observables is an important goal for cluster cosmology. In this work, we introduce a new matched filter richness estimator, and test its performance using the maxBCG cluster catalog. Our new estimator significantly reduces the variance in the L{sub X}-richness relation, from {sigma}{sub lnL{sub X}}{sup 2} = (0.86 {+-} 0.02){sup 2} to {sigma}{sub lnL{sub X}}{sup 2} = (0.69 {+-} 0.02){sup 2}. Relative to the maxBCG richness estimate, it also removes the strong redshift dependence of the richness scaling relations, and is significantly more robust to photometric and redshift errors. These improvements are largely due to our more sophisticated treatment of galaxy color data. We also demonstrate the scatter in the L{sub X}-richness relation depends on the aperture used to estimate cluster richness, and introduce a novel approach for optimizing said aperture which can be easily generalized to other mass tracers.

Study of the interactions between a proline-rich protein and a flavan-3-ol by NMR: residual structures in the natively unfolded protein provides anchorage points for the ligands.

Science.gov (United States)

Pascal, Christine; Paté, Franck; Cheynier, Véronique; Delsuc, Marc-André

2009-09-01

Astringency is one of the major organoleptic properties of food and beverages that are made from plants, such as tea, chocolate, beer, or red wine. This sensation is thought to be due to interactions between tannins and salivary proline-rich proteins, which are natively unfolded proteins. A human salivary proline-rich protein, namely IB-5, was produced by the recombinant method. Its interactions with a model tannin, epigallocatechin gallate (EGCG), the major flavan-3-ol in green tea, were studied here. Circular dichroism experiments showed that IB-5 presents residual structures (PPII helices) when the ionic strength is close to that in saliva. In the presence of these residual structures, IB-5 undergoes an increase in structural content upon binding to EGCG. NMR data corroborated the presence of preformed structural elements within the protein prior to binding and a partial assignment was proposed, showing partial structuration. TOCSY experiments showed that amino acids that are involved in PPII helices are more likely to interact with EGCG than those in random coil regions, as if they were anchorage points for the ligand. The signal from IB-5 in the DOSY NMR spectrum revealed an increase in polydispersity upon addition of EGCG while the mean hydrodynamic radius remained unchanged. This strongly suggests the formation of IB-5/EGCG aggregates.

Biogeographical region and host trophic level determine carnivore endoparasite richness in the Iberian Peninsula.

Science.gov (United States)

Rosalino, L M; Santos, M J; Fernandes, C; Santos-Reis, M

2011-05-01

We address the question of whether host and/or environmental factors might affect endoparasite richness and distribution, using carnivores as a model. We reviewed studies published in international peer-reviewed journals (34 areas in the Iberian Peninsula), describing parasite prevalence and richness in carnivores, and collected information on site location, host bio-ecology, climate and detected taxa (Helminths, Protozoa and Mycobacterium spp.). Three hypotheses were tested (i) host based, (ii) environmentally based, and (iii) hybrid (combination of environmental and host). Multicollinearity reduced candidate variable number for modelling to 5: host weight, phylogenetic independent contrasts (host weight), mean annual temperature, host trophic level and biogeographical region. General Linear Mixed Modelling was used and the best model was a hybrid model that included biogeographical region and host trophic level. Results revealed that endoparasite richness is higher in Mediterranean areas, especially for the top predators. We suggest that the detected parasites may benefit from mild environmental conditions that occur in southern regions. Top predators have larger home ranges and are likely to be subjected to cascading effects throughout the food web, resulting in more infestation opportunities and potentially higher endoparasite richness. This study suggests that richness may be more affected by historical and regional processes (including climate) than by host ecological processes.

[Altitudinal distribution, richness and composition of bird assemblages in a mountainous region in Southern Nayarit, Mexico].

Science.gov (United States)

Jaime-Escalante, Nidia Gissell; Figueroa-Esquivel, Elsa Margarita; Villaseñor Gómez, José Fernando; Jacobo-Sapien, Edwin Alberto; Puebla-Olivares, Fernando

2016-12-01

Elevation gradient studies have strengthened the evaluation of changes in richness and composition of bird assemblages. They also provide information on environmental variables that determine bird distribution, and the variables that define their population structure. Our aim was to describe their variation through an elevational cline in Southern Nayarit, Mexico. To analyze the behavior of richness across the gradient, we gathered information through point counts in nine elevational intervals (300 m from each other) from sea level to 2 700 m of elevation. With a standardized sampling effort, we produced rarefaction curves and analyzed changes in species composition by hierarchical classification using the TWINSPAN technique. In order to identify variables associated with richness changes, we examined the effect of precipitation and habitat structure via regression trees. An analysis of nonmetric multidimensional scaling (NMDS) was implemented with the purpose to determine if the changes in composition correspond to changes in vegetation types. Species richness varied significantly across the gradient: high in the lower parts of the gradient, reached its peak in the middle, and decreased monotonically with elevation. Species responded to changes in the cline and were grouped in three elevational zones. Analyses suggest that changes in richness and species composition are influenced by vegetation, its structure and precipitation regime, as well as various aspects related to habitat features and disturbance. These aspects should be taken into account in order to design appropriate strategies for the conservation of the birds of Nayarit.

Recognition of AT-Rich DNA Binding Sites by the MogR Repressor

Energy Technology Data Exchange (ETDEWEB)

Shen, Aimee; Higgins, Darren E.; Panne, Daniel; (Harvard-Med); (EMBL)

2009-07-22

The MogR transcriptional repressor of the intracellular pathogen Listeria monocytogenes recognizes AT-rich binding sites in promoters of flagellar genes to downregulate flagellar gene expression during infection. We describe here the 1.8 A resolution crystal structure of MogR bound to the recognition sequence 5' ATTTTTTAAAAAAAT 3' present within the flaA promoter region. Our structure shows that MogR binds as a dimer. Each half-site is recognized in the major groove by a helix-turn-helix motif and in the minor groove by a loop from the symmetry-related molecule, resulting in a 'crossover' binding mode. This oversampling through minor groove interactions is important for specificity. The MogR binding site has structural features of A-tract DNA and is bent by approximately 52 degrees away from the dimer. The structure explains how MogR achieves binding specificity in the AT-rich genome of L. monocytogenes and explains the evolutionary conservation of A-tract sequence elements within promoter regions of MogR-regulated flagellar genes.

Repeated burning of eastern tallgrass prairie increases richness and diversity, stabilizing late successional vegetation.

Science.gov (United States)

Bowles, Marlin L; Jones, Michael D

2013-03-01

Understanding temporal effects of fire frequency on plant species diversity and vegetation structure is critical for managing tallgrass prairie (TGP), which occupies a mid-continental longitudinal precipitation and productivity gradient. Eastern TGP has contributed little information toward understanding whether vegetation-fire interactions are uniform or change across this biome. We resampled 34 fire-managed mid- and late-successional ungrazed TGP remnants occurring across a dry to wet-mesic moisture gradient in the Chicago region of Illinois, USA. We compared hypotheses that burning acts either as a stabilizing force or causes change in diversity and structure, depending upon fire frequency and successional stage. Based on western TGP, we expected a unimodal species richness distribution across a cover-productivity gradient, variable functional group responses to fire frequency, and a negative relationship between fire frequency and species richness. Species diversity was unimodal across the cover gradient and was more strongly humpbacked in stands with greater fire frequency. In support of a stabilizing hypothesis, temporal similarity of late-successional vegetation had a logarithmic relationship with increasing fire frequency, while richness and evenness remained stable. Temporal similarity within mid-successional stands was not correlated with fire frequency, while richness increased and evenness decreased over time. Functional group responses to fire frequency were variable. Summer forb richness increased under high fire frequency, while C4 grasses, spring forbs, and nitrogen-fixing species decreased with fire exclusion. On mesic and wet-mesic sites, vegetation structure measured by the ratio of woody to graminoid species was negatively correlated with abundance of forbs and with fire frequency. Our findings that species richness responds unimodally to an environmental-productivity gradient, and that fire exclusion increases woody vegetation and leads to loss

Seed plant phylogenetic diversity and species richness in conservation planning within a global biodiversity hotspot in eastern Asia.

Science.gov (United States)

Li, Rong; Kraft, Nathan J B; Yu, Haiying; Li, Heng

2015-12-01

One of the main goals of conservation biology is to understand the factors shaping variation in biodiversity across the planet. This understanding is critical for conservation planners to be able to develop effective conservation strategies. Although many studies have focused on species richness and the protection of rare and endemic species, less attention has been paid to the protection of the phylogenetic dimension of biodiversity. We explored how phylogenetic diversity, species richness, and phylogenetic community structure vary in seed plant communities along an elevational gradient in a relatively understudied high mountain region, the Dulong Valley, in southeastern Tibet, China. As expected, phylogenetic diversity was well correlated with species richness among the elevational bands and among communities. At the community level, evergreen broad-leaved forests had the highest levels of species richness and phylogenetic diversity. Using null model analyses, we found evidence of nonrandom phylogenetic structure across the region. Evergreen broad-leaved forests were phylogenetically overdispersed, whereas other vegetation types tended to be phylogenetically clustered. We suggest that communities with high species richness or overdispersed phylogenetic structure should be a focus for biodiversity conservation within the Dulong Valley because these areas may help maximize the potential of this flora to respond to future global change. In biodiversity hotspots worldwide, we suggest that the phylogenetic structure of a community may serve as a useful measure of phylogenetic diversity in the context of conservation planning. © 2015 Society for Conservation Biology.

Crystal structure of LGR4-Rspo1 complex: insights into the divergent mechanisms of ligand recognition by leucine-rich repeat G-protein-coupled receptors (LGRs).

Science.gov (United States)

Xu, Jin-Gen; Huang, Chunfeng; Yang, Zhengfeng; Jin, Mengmeng; Fu, Panhan; Zhang, Ni; Luo, Jian; Li, Dali; Liu, Mingyao; Zhou, Yan; Zhu, Yongqun

2015-01-23

Leucine-rich repeat G-protein-coupled receptors (LGRs) are a unique class of G-protein-coupled receptors characterized by a large extracellular domain to recognize ligands and regulate many important developmental processes. Among the three groups of LGRs, group B members (LGR4-6) recognize R-spondin family proteins (Rspo1-4) to stimulate Wnt signaling. In this study, we successfully utilized the "hybrid leucine-rich repeat technique," which fused LGR4 with the hagfish VLR protein, to obtain two recombinant human LGR4 proteins, LGR415 and LGR49. We determined the crystal structures of ligand-free LGR415 and the LGR49-Rspo1 complex. LGR4 exhibits a twisted horseshoe-like structure. Rspo1 adopts a flat and β-fold architecture and is bound in the concave surface of LGR4 in the complex through electrostatic and hydrophobic interactions. All the Rspo1-binding residues are conserved in LGR4-6, suggesting that LGR4-6 bind R-spondins through an identical surface. Structural analysis of our LGR4-Rspo1 complex with the previously determined LGR4 and LGR5 structures revealed that the concave surface of LGR4 is the sole binding site for R-spondins, suggesting a one-site binding model of LGR4-6 in ligand recognition. The molecular mechanism of LGR4-6 is distinct from the two-step mechanism of group A receptors LGR1-3 and the multiple-interface binding model of group C receptors LGR7-8, suggesting LGRs utilize the divergent mechanisms for ligand recognition. Our structures, together with previous reports, provide a comprehensive understanding of the ligand recognition by LGRs. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

A systematic study of band structure and electromagnetic properties of neutron rich odd mass Eu isotopes in the projected shell model framework

Energy Technology Data Exchange (ETDEWEB)

Pandit, Rakesh K.; Devi, Rani [University of Jammu, Department of Physics and Electronics, Jammu (India); Khosa, S.K. [Central University of Jammu, Department of Physics and Astronomical Sciences, Jammu (India); Bhat, G.H.; Sheikh, J.A. [University of Kashmir, Department of Physics, Srinagar (India)

2017-10-15

The positive and negative parity rotational band structure of the neutron rich odd mass Eu isotopes with neutron numbers ranging from 90 to 96 are investigated up to the high angular momentum. In the theoretical analysis of energy spectra, transition energies and electromagnetic transition probabilities we employ the projected shell model. The calculations successfully describe the formation of the ground and excited band structures from the single particle and multi quasiparticle configurations. Calculated excitation energy spectra, transition energies, exact quantum mechanically calculated B(E2) and B(M1) transition probabilities are compared with experimental data wherever available and a reasonably good agreement is obtained with the observed data. The change in deformation in the ground state band with the increase in angular momentum and the increase in neutron number has also been established. (orig.)

Deep-UV Raman spectroscopic analysis of structure and dissolution rates of silica-rich sodium borosilicate glasses

Energy Technology Data Exchange (ETDEWEB)

Windisch, Charles F.; Pierce, Eric M.; Burton, Sarah D.; Bovaird, Chase C.

2011-03-24

As part of ongoing studies to evaluate the relationships between structural variations in silicate glasses and rates of glass dissolution in aqueous media, molecular structures present in sodium borosilicate glasses of composition Na2O.xB2O3.(3-x)SiO2, with x 1 (Na2O/B2O3 ratio 1), were analyzed using deep-UV Raman spectroscopy. The results were quantified in terms of the fraction of SiO4 tetrahedra with one non-bridging oxygen (Q3) and then correlated with Na2O and B2O3 content. Increasing Na2O was found to raise the fraction of Q3 units in the glasses systematically, in agreement with studies on related glasses, and, as long as the value of x was not too high, contribute to higher rates of dissolution in single pass flow-through testing. The finding was obtained across more than one series of silica-rich glasses prepared for independent dissolution studies. In contrast, dissolution rates were less strongly determined by the Q3 fraction when the value of x was near unity and appeared to grow larger upon further reduction of the Q3 fraction. The results were interpreted to indicate the increasingly important role of network hydrolysis in the glass dissolution mechanism as the BO4 tetrahedron replaces the Q3 unit as the charge-compensating structure for Na+ ions. Finally, the use of deep-UV Raman spectroscopy was found to be advantageous in studying finely powdered glasses in cases where visible Raman spectroscopy suffered from weak Raman scattering and fluorescence interference.

LHCB RICH gas system proposal

CERN Document Server

Bosteels, Michel; Haider, S

2001-01-01

Both LHCb RICH will be operated with fluorocarbon as gas radiator. RICH 1 will be filled with 4m^3 of C4F10 and RICH 2 with 100m^3 of CF4. The gas systems will run as a closed loop circulation and a gas recovery system within the closed loop is planned for RICH 1, where the recovery of the CF4 will only be realised during filling and emptying of the detector. Inline gas purification is foreseen for the gas systems in order to limit water and oxygen impurities.

The environment, not space, dominantly structures the landscape patterns of the richness and composition of the tropical understory vegetation.

Directory of Open Access Journals (Sweden)

Yue-Hua Hu

Full Text Available The mechanisms driving the spatial patterns of species richness and composition are essential to the understanding of biodiversity. Numerous studies separately identify the contributions of the environment (niche process and space (neutral process to the species richness or composition at different scales, but few studies have investigated the contributions of both types of processes in the two types of data at the landscape scale. In this study, we partitioned the spatial variations in all, exotic and native understory plant species richness and composition constrained by environmental variables and space in 134 plots that were spread across 10 counties in Hainan Island in southern China. The 134 plots included 70 rubber (Hevea brasiliensis plantation plots, 50 eucalyptus (Eucalyptus urophylla plantation plots, and 14 secondary forest plots. RDA based variation partitioning was run to assess the contribution of environment and space to species richness and composition. The results showed that the environmental variables alone explained a large proportion of the variations in both the species richness and composition of all, native, and exotic species. The RDA results indicated that overstory composition (forest type here plays a leading role in determining species richness and composition patterns. The alpha and beta diversities of the secondary forest plots were markedly higher than that of the two plantations. In conclusion, niche differentiation processes are the principal mechanisms that shape the alpha and beta diversities of understory plant species in Hainan Island.

Exploration and guidance in media-rich information spaces : the implementation and realization of guided tours in digital dossiers

NARCIS (Netherlands)

Riel, van C.; Wang, Y.; Eliëns, A.; Guerrero-Bote, V.P.

2006-01-01

Confronted with media-rich information spaces involves interfaces that are usually designed to facilitate personal exploration to locate information of interest. Navigating such media-rich information spaces, where information structures can be complex, may result in disorientation and demotivation.

A mineral-rich extract from the red marine algae Lithothamnion calcareum preserves bone structure and function in female mice on a Western-style diet.

Science.gov (United States)

Aslam, Muhammad Nadeem; Kreider, Jaclynn M; Paruchuri, Tejaswi; Bhagavathula, Narasimharao; DaSilva, Marissa; Zernicke, Ronald F; Goldstein, Steven A; Varani, James

2010-04-01

The purpose of this study was to determine whether a mineral-rich extract derived from the red marine algae Lithothamnion calcareum could be used as a dietary supplement for prevention of bone mineral loss. Sixty C57BL/6 mice were divided into three groups based on diet: the first group received a high-fat Western-style diet (HFWD), the second group was fed the same HFWD along with the mineral-rich extract included as a dietary supplement, and the third group was used as a control and was fed a low-fat rodent chow diet (AIN76A). Mice were maintained on the respective diets for 15 months. Then, long bones (femora and tibiae) from both males and females were analyzed by three-dimensional micro-computed tomography (micro-CT) and (bones from female mice) concomitantly assessed in bone strength studies. Tartrate-resistant acid phosphatase (TRAP), osteocalcin, and N-terminal peptide of type I procollagen (PINP) were assessed in plasma samples obtained from female mice at the time of sacrifice. To summarize, female mice on the HFWD had reduced bone mineralization and reduced bone strength relative to female mice on the low-fat chow diet. The bone defects in female mice on the HFWD were overcome in the presence of the mineral-rich supplement. In fact, female mice receiving the mineral-rich supplement in the HFWD had better bone structure/function than did female mice on the low-fat chow diet. Female mice on the mineral-supplemented HFWD had higher plasma levels of TRAP than mice of the other groups. There were no differences in the other two markers. Male mice showed little diet-specific differences by micro-CT.

[Position of health at international relations. Part I. Structural dimensions of health].

Science.gov (United States)

Cianciara, Dorota; Wysocki, Mirosław J

2011-01-01

In the article, the health is perceived as complex, multidimensional concept and not as absence of disease. This is consistent with public health perspective, where public health is regarded as public as well as political activity. It aims to solve health and social problems, depends on analysis of phenomena, needs the negotiations and relies on making decision on feasible directions of changes--what, why, how, where, when and by whom should be done. Public health policy developed as a result of international relations, and UN family fora especially, is regarded as significant for creating of health position. The aim of this article was: (1) the analysis of selected concepts and definitions related to structural dimensions of health, used in UN international arrangements; (2) an attempt to explain the evolution of health structure notions at worldwide agenda. The UN main bodies, programmes and funds working on the health field are mentioned and voting rules in UN General Assembly and World Health Assembly are reminded. The following structural dimensions were considered: (a) well-being, (b) human rights, (c) everyday resource, health potential, (4) equity. All were explored in WHO Constitution, Universal Declaration of Human Rights, International Covenant on Economic, Social and Cultural Rights, Ottawa Charter for Health Promotion and numerous WHA and UN GA resolutions, decisions as well as other documents. Some remarkable differences in English and Polish language versions and meanings were pointed out. It was argued that present perception of structural dimension of health is strongly derived from the preamble of the WHO Constitution adopted and signed on 22 July 1946 by the representatives of 61 States. It is an evidence of the strength of this document and wisdom of its authors. The greater progress is associated. with concepts and notion of organizational dimensions of health perceived as action and processes leading to health. Long-term efforts to strengthen

Floral abundance, richness, and spatial distribution drive urban garden bee communities.

Science.gov (United States)

Plascencia, M; Philpott, S M

2017-10-01

In urban landscapes, gardens provide refuges for bee diversity, but conservation potential may depend on local and landscape features. Foraging and population persistence of bee species, as well as overall pollinator community structure, may be supported by the abundance, richness, and spatial distribution of floral resources. Floral resources strongly differ in urban gardens. Using hand netting and pan traps to survey bees, we examined whether abundance, richness, and spatial distribution of floral resources, as well as ground cover and garden landscape surroundings influence bee abundance, species richness, and diversity on the central coast of California. Differences in floral abundance and spatial distribution, as well as urban cover in the landscape, predicted different bee community variables. Abundance of all bees and of honeybees (Apis mellifera) was lower in sites with more urban land cover surrounding the gardens. Honeybee abundance was higher in sites with patchy floral resources, whereas bee species richness and bee diversity was higher in sites with more clustered floral resources. Surprisingly, bee species richness and bee diversity was lower in sites with very high floral abundance, possibly due to interactions with honeybees. Other studies have documented the importance of floral abundance and landscape surroundings for bees in urban gardens, but this study is the first to document that the spatial arrangement of flowers strongly predicts bee abundance and richness. Based on these findings, it is likely that garden managers may promote bee conservation by managing for floral connectivity and abundance within these ubiquitous urban habitats.

Resilience of Core-Periphery Networks in the Case of Rich-Club

Directory of Open Access Journals (Sweden)

Matteo Cinelli

2017-01-01

Full Text Available Core-periphery networks are structures that present a set of central and densely connected nodes, namely, the core, and a set of noncentral and sparsely connected nodes, namely, the periphery. The rich-club refers to a set in which the highest degree nodes show a high density of connections. Thus, a network that displays a rich-club can be interpreted as a core-periphery network in which the core is made up of a number of hubs. In this paper, we test the resilience of networks showing a progressively denser rich-club and we observe how this structure is able to affect the network measures in terms of both cohesion and efficiency in information flow. Additionally, we consider the case in which, instead of making the core denser, we add links to the periphery. These two procedures of core and periphery thickening delineate a decision process in the placement of new links and allow us to conduct a scenario analysis that can be helpful in the comprehension and supervision of complex networks under the resilience perspective. The advantages of the two procedures, as well as their implications, are discussed in relation to both network efficiency and node heterogeneity.

Investigating Move Structure of English Applied Linguistics Research Article Discussions Published in International and Thai Journals

Science.gov (United States)

Amnuai, Wirada; Wannaruk, Anchalee

2013-01-01

This study investigates the rhetorical move structure of English applied linguistic research article Discussions published in Thai and international journals. Two corpora comprising of 30 Thai Discussions and 30 international Discussions were analyzed using Yang & Allison's (2003) move model. Based on the analysis, both similarities and…

8th international conference on electronic spectroscopy and structure

Energy Technology Data Exchange (ETDEWEB)

Robinson, Art

2000-10-16

Gathering from 33 countries around the world, 408 registrants and a number of local drop-in participants descended on the Clark Kerr Campus of the University of California, Berkeley, from Monday, August 7 through Saturday, August 12, 2000 for the Eighth International Conference on Electronic Structure and Spectroscopy (ICESS8). At the conference, participants benefited from an extensive scientific program comprising more than 100 oral presentations (plenary lectures and invited and contributed talks) and 330 poster presentations, as well as ample time for socializing and a tour of the Advanced Light Source (ALS) at the nearby Lawrence Berkeley National Laboratory.

β decay studies of n-rich Cs isotopes with the ISOLDE Decay Station

Science.gov (United States)

Lică, R.; Benzoni, G.; Morales, A. I.; Borge, M. J. G.; Fraile, L. M.; Mach, H.; Madurga, M.; Sotty, C.; Vedia, V.; De Witte, H.; Benito, J.; Berry, T.; Blasi, N.; Bracco, A.; Camera, F.; Ceruti, S.; Charviakova, V.; Cieplicka-Oryńczak, N.; Costache, C.; Crespi, F. C. L.; Creswell, J.; Fernández-Martínez, G.; Fynbo, H.; Greenlees, P.; Homm, I.; Huyse, M.; Jolie, J.; Karayonchev, V.; Köster, U.; Konki, J.; Kröll, T.; Kurcewicz, J.; Kurtukian-Nieto, T.; Lazarus, I.; Leoni, S.; Lund, M.; Marginean, N.; Marginean, R.; Mihai, C.; Mihai, R.; Negret, A.; Orduz, A.; Patyk, Z.; Pascu, S.; Pucknell, V.; Rahkila, P.; Regis, J. M.; Rotaru, F.; Saed-Sami, N.; Sánchez-Tembleque, V.; Stanoiu, M.; Tengblad, O.; Thuerauf, M.; Turturica, A.; Van Duppen, P.; Warr, N.

2017-05-01

Neutron-rich Ba isotopes are expected to exhibit octupolar correlations, reaching their maximum in isotopes around mass A = 146. The odd-A neutron-rich members of this isotopic chain show typical patterns related to non-axially symmetric shapes, which are however less marked compared to even-A ones, pointing to a major contribution from vibrations. In the present paper we present results from a recent study focused on 148-150Cs β-decay performed at the ISOLDE Decay Station equipped with fast-timing detectors. A detailed analysis of the measured decay half-lives and decay scheme of 149Ba is presented, giving a first insight in the structure of this neutron-rich nucleus.

Platelet-rich plasma and chronic wounds: remaining fibronectin may influence matrix remodeling and regeneration success.

Science.gov (United States)

Moroz, Andrei; Deffune, Elenice

2013-11-01

Platelet-rich plasma has been largely used as a therapeutic option for the treatment of chronic wounds of different etiologies. The enhanced regeneration observed after the use of platelet-rich plasma has been systematically attributed to the growth factors that are present inside platelets' granules. We hypothesize that the remaining plasma and platelet-bound fibronectin may act as a further bioactive protein in platelet-rich plasma preparations. Recent reports were analyzed and presented as direct evidences of this hypotheses. Fibronectin may directly influence the extracellular matrix remodeling during wound repair. This effect is probably through matrix metalloproteinase expression, thus exerting an extra effect on chronic wound regeneration. Physicians should be well aware of the possible fibronectin-induced effects in their future endeavors with PRP in chronic wound treatment. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

The effect of internal magnetic structure on the fishbone instability

International Nuclear Information System (INIS)

Roberts, D.W.; Powell, E.; Kaita, R.; Bell, R.; Chance, M.; Hatcher, R.; Holland, A.; Kaye, S.; Kessel, C.; Kugel, H.; LeBlanc, B.; Manickam, J.; Okabayashi, M.; Paul, S.; Pomphrey, N.; Sauthoff, N.; Sesnic, S.; Takahashi, H.; White, R.; Asakura, N.; Duperrex, P.; Gammel, G.

1992-01-01

Plasmas exhibiting the ''fishbone'' instability studied on the PBX-M tokamak show a distinct relationship between the plasma shape, the internal magnetic structure, and the presence or absence of fast ion losses associated with the fishbone mode. We have, for the first time, carried out measurements of the magnetic safety factor profile in fishbone-unstable plasmas, and used the knowledge of the associated experimental equilibria to compare the stability and fast ion loss properties of these plasmas with experimental observations

Enzymatic preparation of "functional oil" rich in feruloylated structured lipids with solvent-free ultrasound pretreatment.

Science.gov (United States)

Zhang, Haiping; Zheng, Mingming; Shi, Jie; Tang, Hu; Deng, Qianchun; Huang, Fenghong; Luo, Dan

2018-05-15

In this study, a series of functional oils rich in feruloylated structured lipids (FSLs) was prepared by enzymatic transesterification of ethyl ferulate (EF) with triglycerides under ultrasound pretreatment. A conversion of more than 92.7% and controllable FSLs (3.1%-26.3%) can be obtained under the following conditions: 16% enzyme, substrate ratio 1:5 (oil/EF, mol/mol), 85 °C, ultrasound 1 h, pulse mode 3 s/3s (working/waiting), and 17.0 W/mL. Compared to conventional mechanical stirring, the activation energy decreased from 50.0 kJ/mol to 40.7 kJ/mol. The apparent kinetic constant increased by more than 13 times, and the time required for the maximum conversion reduced sharply from 20-60 h to 4-6h, which was the fastest rate for enzymatic synthesis of FSLs. The antioxidant activities of the functional oil significantly increased 1.0- to 8.1-fold more than that of the raw oil. The functional oil could be widely applied in various fields of functional foods. Copyright © 2017 Elsevier Ltd. All rights reserved.

Structure study and properties of rare earth-rich glassed for the conditioning of nuclear waste

International Nuclear Information System (INIS)

Bardez, I.

2004-11-01

A new nuclear glass composition, able to immobilize highly radioactive liquid wastes from high burn-up UO 2 fuel, was established and its structure studied. The composition of the selected rare earth-rich glass is (molar %): 61.79 SiO 2 - 8.94 B 2 O 3 - 3.05 Al 2 O 3 - 14.41 Na 2 O - 6.32 CaO - 1.89 ZrO 2 - 3.60 RE 2 O 3 (with RE = La, Ce, Pr and Nd) The aim of this study was to determine the local environment of the rare earth in this glass and also to glean information about the effect of glass composition on the rare earth neighbouring (influence of Si, B, Al, Na and Ca contents). To this end, several series of glasses, prepared from the baseline glass, were studied by different characterisation methods such as EXAFS spectroscopy at the neodymium L III -edge, optical absorption spectroscopy, Raman spectroscopy and 29 Si, 27 Al and 11 B MAS-NMR. By coupling all the results obtained, several hypotheses about the nature of the rare earth neighbouring in the glass were proposed. (author)

The HADES-RICH upgrade using Hamamatsu H12700 MAPMTs with DiRICH FEE + Readout

Science.gov (United States)

Patel, V.; Traxler, M.

2018-03-01

The High Acceptance Di-Electron Spectrometer (HADES) is operational since the year 2000 and uses a hadron blind RICH detector for electron identification. The RICH photon detector is currently replaced by Hamamatsu H12700 MAPMTs with a readout system based on the DiRICH front-end module. The electronic readout chain is being developed as a joint effort of the HADES-, CBM- and PANDA collaborations and will also be used in the photon detectors for the upcoming Compressed Baryonic Matter (CBM) and PANDA experiments at FAIR . This article gives a brief overview on the photomultipliers and their quality assurance test measurements, as well as first measurements of the new DiRICH front-end module in final configurations.

Acoustic richness modulates the neural networks supporting intelligible speech processing.

Science.gov (United States)

Lee, Yune-Sang; Min, Nam Eun; Wingfield, Arthur; Grossman, Murray; Peelle, Jonathan E

2016-03-01

The information contained in a sensory signal plays a critical role in determining what neural processes are engaged. Here we used interleaved silent steady-state (ISSS) functional magnetic resonance imaging (fMRI) to explore how human listeners cope with different degrees of acoustic richness during auditory sentence comprehension. Twenty-six healthy young adults underwent scanning while hearing sentences that varied in acoustic richness (high vs. low spectral detail) and syntactic complexity (subject-relative vs. object-relative center-embedded clause structures). We manipulated acoustic richness by presenting the stimuli as unprocessed full-spectrum speech, or noise-vocoded with 24 channels. Importantly, although the vocoded sentences were spectrally impoverished, all sentences were highly intelligible. These manipulations allowed us to test how intelligible speech processing was affected by orthogonal linguistic and acoustic demands. Acoustically rich speech showed stronger activation than acoustically less-detailed speech in a bilateral temporoparietal network with more pronounced activity in the right hemisphere. By contrast, listening to sentences with greater syntactic complexity resulted in increased activation of a left-lateralized network including left posterior lateral temporal cortex, left inferior frontal gyrus, and left dorsolateral prefrontal cortex. Significant interactions between acoustic richness and syntactic complexity occurred in left supramarginal gyrus, right superior temporal gyrus, and right inferior frontal gyrus, indicating that the regions recruited for syntactic challenge differed as a function of acoustic properties of the speech. Our findings suggest that the neural systems involved in speech perception are finely tuned to the type of information available, and that reducing the richness of the acoustic signal dramatically alters the brain's response to spoken language, even when intelligibility is high. Copyright © 2015 Elsevier

On the nature of the Cu-rich aggregates in brain astrocytes

Energy Technology Data Exchange (ETDEWEB)

Sullivan, Brendan; Robison, Gregory; Osborn, Jenna; Kay, Martin; Thompson, Peter; Davis, Katherine; Zakharova, Taisiya; Antipova, Olga; Pushkar, Yulia

2017-04-01

Fulfilling a bevy of biological roles, copper is an essential metal for healthy brain function. Cu dyshomeostasis has been demonstrated to be involved in some neurological conditions including Menkes and Alzheimer’s diseases. We have previously reported localized Cu-rich aggregates in astrocytes of the subventricular zone (SVZ) in rodent brains with Cu concentrations in the hundreds of millimolar. Metallothionein, a cysteine-rich protein critical to metal homeostasis and known to participate in a variety of neuroprotective and neuroregenerative processes, was proposed as a binding protein. Here, we present an analysis of metallothionein(1,2) knockout (MTKO) mice and age-matched controls using X-ray fluorescence microscopy. In large structures such as the corpus callosum, cortex, and striatum, there is no significant difference in Cu, Fe, or Zn concentrations in MTKO mice compared to age-matched controls. In the astrocyte-rich subventricular zone where Cu-rich aggregates reside, approximately 1/3 as many Cu-rich aggregates persist in MTKO mice resulting in a decrease in periventricular Cu concentration. Aggregates in both wild-type and MTKO mice show XANES spectra characteristic of CuxSy multimetallic clusters and have similar [S]/[Cu] ratios. Consistent with assignment as a CuxSy multimetallic cluster, the astrocyte-rich SVZ of both MTKO and wild-type mice exhibit autofluorescent bodies, though MTKO mice exhibit fewer. Furthermore, XRF imaging of Au-labeled lysosomes and ubiquitin demonstrates a lack of co-localization with Cu-rich aggregates suggesting they are not involved in a degradation pathway. Overall, these data suggest that Cu in aggregates is bound by either metallothionein-3 or a yet unknown protein similar to metallothionein.

Direct experimental determination of the atomic structure at internal interfaces

Energy Technology Data Exchange (ETDEWEB)

Browning, N.D. [Oak Ridge National Lab., TN (United States)]|[Illinois Univ., Chicago, IL (United States); Pennycook, S.J. [Oak Ridge National Lab., TN (United States)

1995-07-01

A crucial first step in understanding the effect that internal interfaces have on the properties of materials is the ability to determine the atomic structure at the interface. As interfaces can contain atomic disorder, dislocations, segregated impurities and interphases, sensitivity to all of these features is essential for complete experimental characterization. By combining Z-contrast imaging and electron energy loss spectroscopy (EELS) in a dedicated scanning transmission electron microscope (STEM), the ability to probe the structure, bonding and composition at interfaces with the necessary atomic resolution has been obtained. Experimental conditions can be controlled to provide, simultaneously, both incoherent imaging and spectroscopy. This enables interface structures observed in the image to be interpreted intuitively and the bonding in a specified atomic column to be probed directly by EELS. The bonding and structure information can then be correlated using bond-valence sum analysis to produce structural models. This technique is demonstrated for 25{degrees}, 36{degrees} and 67{degrees} symmetric and 45{degrees} and 25{degrees} asymmetric [001] tilt grain boundaries in SrTiO{sub 3} The structures of both types of boundary were found to contain partially occupied columns in the boundary plane. From these experimental results, a series of structural units were identified which could be combined, using continuity of gain boundary structure principles, to construct all [001] tilt boundaries in SrTiO{sub 3}. Using these models, the ability of this technique to address the issues of vacancies and dopant segregation at grain boundaries in electroceramics is discussed.

A New International Standard for "Actions from Waves and Currents on Coastal Structures"

DEFF Research Database (Denmark)

Tørum, Alf; Burcharth, Hans F.; Goda, Yoshimi

2007-01-01

The International Organization for Standardization (ISO) is going to issue a new standard concerning "Actions from Waves and Currents on Coastal Structures," which becomes the first international standard in coastal engineering. It is composed of a normative part (29 pages), an informative part (80...... pages) and Bibliography ( 17 pages). The normative part describes what is considered as the norm of the matters in concern, while the informative part provides the information on recommended practice. The paper introduces the main points of the normative part and discusses the influence of the new...

New directions towards structure formation and stability of protein-rich foods from globular proteins

NARCIS (Netherlands)

Purwanti, N.; Goot, van der A.J.; Boom, R.M.; Vereijken, J.M.

2010-01-01

Concentrated protein-rich foods have strong potential to be developed in terms of health and well-being roles. Unfortunately, limitations in creating products with the rights texture and stability hinder the use of those products by consumers. Main reason is that the formation of micro- and

Artificial maturation of an immature sulfur- and organic matter-rich limestone from the Ghareb Formation, Jordan

Science.gov (United States)

Koopmans, M.P.; Rijpstra, W.I.C.; De Leeuw, J. W.; Lewan, M.D.; Damste, J.S.S.

1998-01-01

An immature (Ro=0.39%), S-rich (S(org)/C = 0.07), organic matter-rich (19.6 wt. % TOC) limestone from the Ghareb Formation (Upper Cretaceous) in Jordan was artificially matured by hydrous pyrolysis (200, 220 ..., 300??C; 72 h) to study the effect of progressive diagenesis and early catagenesis on the amounts and distributions of hydrocarbons, organic sulfur compounds and S-rich geomacromolecules. The use of internal standards allowed the determination of absolute amounts. With increasing thermal maturation, large amounts of alkanes and alkylthiophenes with predominantly linear carbon skeletons are generated from the kerogen. The alkylthiophene isomer distributions do not change significantly with increasing thermal maturation, indicating the applicability of alkylthiophenes as biomarkers at relatively high levels of thermal maturity. For a given carbon skeleton, the saturated hydrocarbon, alkylthiophenes and alkylbenzo[b]thiophenes are stable forms at relatively high temperatures, whereas the alkylsulfides are not stable. The large amount of alkylthiophenes produced relative to the alkanes may be explained by the large number of monosulfide links per carbon skeleton. These results are in good agreement with those obtained previously for an artificial maturation series of an immature S-rich sample from the Gessoso-solfifera Formation.An immature (Ro = 0.39%), S-rich (Sorg/C = 0.07), organic matter-rich (19.6 wt.% TOC) limestone from the Ghareb Formation (Upper Cretaceous) in Jordan was artificially matured by hydrous pyrolysis (200, 220, ..., 300??C; 72 h) to study the effect of progressive diagenesis and early catagenesis on the amounts and distributions of hydrocarbons, organic sulfur compounds and S-rich geomacromolecules. The use of internal standards allowed the determination of absolute amounts. With increasing thermal maturation, large amounts of alkanes and alkylthiophenes with predominantly linear carbon skeletons are generated from the kerogen. The

Screening of ligands for the Ullmann synthesis of electron-rich diaryl ethers.

Science.gov (United States)

Otto, Nicola; Opatz, Till

2012-01-01

In the search for new ligands for the Ullmann diaryl ether synthesis, permitting the coupling of electron-rich aryl bromides at relatively low temperatures, 56 structurally diverse multidentate ligands were screened in a model system that uses copper iodide in acetonitrile with potassium phosphate as the base. The ligands differed largely in their performance, but no privileged structural class could be identified.

Co-ordination of the international network of nuclear structure and decay data evaluators

International Nuclear Information System (INIS)

Lorenz, A.

1986-10-01

The seventh meeting of the International Network of Nuclear Structure and Decay Data (NSDD) Evaluators concentrated on the organizational aspects of the coordination of the NSDD network and on the presentation and discussion of papers related to the physics of evaluation of NSDD. The report contains short status reports from NSDD Network members, the status of the mass-chain and nuclear structure data, a discussion of evaluation rules and procedures and a short presentation of the next activities

A PUFA-rich diet improves fat oxidation following saturated fat-rich meal.

Science.gov (United States)

Stevenson, Jada L; Miller, Mary K; Skillman, Hannah E; Paton, Chad M; Cooper, Jamie A

2017-08-01

To determine substrate oxidation responses to saturated fatty acid (SFA)-rich meals before and after a 7-day polyunsaturated fatty acid (PUFA)-rich diet versus control diet. Twenty-six, normal-weight, adults were randomly assigned to either PUFA or control diet. Following a 3-day lead-in diet, participants completed the pre-diet visit where anthropometrics and resting metabolic rate (RMR) were measured, and two SFA-rich HF meals (breakfast and lunch) were consumed. Indirect calorimetry was used to determine fat oxidation (Fox) and energy expenditure (EE) for 4 h after each meal. Participants then consumed a PUFA-rich diet (50 % carbohydrate, 15 % protein, 35 % fat, of which 21 % of total energy was PUFA) or control diet (50 % carbohydrate, 15 % protein, 35 % fat, of which 7 % of total energy was PUFA) for the next 7 days. Following the 7-day diet, participants completed the post-diet visit. From pre- to post-PUFA-rich diet, there was no change in RMR (16.3 ± 0.8 vs. 16.4 ± 0.8 kcal/20 min) or in incremental area under the curve for EE (118.9 ± 20.6-126.9 ± 14.1 kcal/8h, ns). Fasting respiratory exchange ratio increased from pre- to post-PUFA-rich diet only (0.83 ± 0.1-0.86 ± 0.1, p diet (0.03 ± 0.1-0.23 ± 0.1 g/15 min for cumulative Fox; p diet initiates greater fat oxidation after eating occasional high SFA meals compared to a control diet, an effect achieved in 7 days.

Structural features facilitating tumor cell targeting and internalization by bleomycin and its disaccharide.

Science.gov (United States)

Yu, Zhiqiang; Paul, Rakesh; Bhattacharya, Chandrabali; Bozeman, Trevor C; Rishel, Michael J; Hecht, Sidney M

2015-05-19

We have shown previously that the bleomycin (BLM) carbohydrate moiety can recapitulate the tumor cell targeting effects of the entire BLM molecule, that BLM itself is modular in nature consisting of a DNA-cleaving aglycone which is delivered selectively to the interior of tumor cells by its carbohydrate moiety, and that there are disaccharides structurally related to the BLM disaccharide which are more efficient than the natural disaccharide at tumor cell targeting/uptake. Because BLM sugars can deliver molecular cargoes selectively to tumor cells, and thus potentially form the basis for a novel antitumor strategy, it seemed important to consider additional structural features capable of affecting the efficiency of tumor cell recognition and delivery. These included the effects of sugar polyvalency and net charge (at physiological pH) on tumor cell recognition, internalization, and trafficking. Since these parameters have been shown to affect cell surface recognition, internalization, and distribution in other contexts, this study has sought to define the effects of these structural features on tumor cell recognition by bleomycin and its disaccharide. We demonstrate that both can have a significant effect on tumor cell binding/internalization, and present data which suggests that the metal ions normally bound by bleomycin following clinical administration may significantly contribute to the efficiency of tumor cell uptake, in addition to their characterized function in DNA cleavage. A BLM disaccharide-Cy5** conjugate incorporating the positively charged dipeptide d-Lys-d-Lys was found to associate with both the mitochondria and the nuclear envelope of DU145 cells, suggesting possible cellular targets for BLM disaccharide-cytotoxin conjugates.

The Effects of Organization Design on Media Richness in Multinational Enterprises.

Science.gov (United States)

Whitfield, J. Michael; And Others

1996-01-01

Examines effects of two organizational design parameters, divisionalization and centralization, on the media richness choices of Chief Executive Officers (CEOs) of multinational enterprises in obtaining information from foreign subsidiaries on strategic issues. Samples 86 US multinationals; finds formal divisional structure affects CEOs' use of…

Internal Structure of Charged Particles in a GRT Gravitational Model

Science.gov (United States)

Khlestkov, Yu. A.; Sukhanova, L. A.

2018-05-01

With the help of an exact solution of the Einstein and Maxwell equations, the internal structure of a multiply connected space of wormhole type with two unclosed static throats leading out of it into two parallel vacuum spaces or into one space is investigated in GRT for a free electric field and dust-like matter. The given geometry is considered as a particle-antiparticle pair with fundamental constants arising in the form of first integrals in the solution of the Cauchy problem - electric charges ±e of opposite sign in the throats and rest mass m0 - the total gravitational mass of the inner world of the particle in the throat. With the help of the energy conservation law, the unremovable rotation of the internal structure is included and the projection of the angular momentum of which onto the rotation axis is identified with the z-projection of the spin of the charged particle. The radius of 2-Gaussian curvature of the throat R* is identified with the charge radius of the particle, and the z-projection of the magnetic moment and the g-factor are found. The feasibility of the given gravitational model is confirmed by the found condition of independence of the spin quantum number of the electron and the proton s = 1/2 of the charge radius R* and the relativistic rest mass m* of the rotating throat, which is reliably confirmed experimentally, and also by the coincidence with high accuracy of the proton radius calculated in the model R*p = 0.8412·10-13 cm with the value of the proton charge radius obtained experimentally by measuring the Lamb shift on muonic hydrogen. The electron in the given model also turns out to be a structured particle with radius R*e = 3.8617·10-11 cm.

Understanding the Potential Content and Structure of an International Convention on the Human Rights of People with Disabilities: Sample Treaty Provisions Drawn from Existing International Instruments. A Reference Tool.

Science.gov (United States)

Lord, Janet E.

This document is designed to prepare advocates in the international disability community for productive participation in the development of international conventions on the human rights of people with disabilities. Knowledge of the standard categories of international law provisions will help participants address issues related to the structure of…

Organic-rich shales from internal Betic basins (SE Spain): potential source rocks analogs for the pre-Messinian Salt play in the western Mediterranean

Energy Technology Data Exchange (ETDEWEB)

Permanyer, A.; Jorge, R.; Baudino, R.; Gilbert, L.

2016-07-01

Southeastern Spain has a large number of Late Neogene basins with substantial evaporitic deposits that developed under an overall NNW-SSE compressional regime related to the African-European tectonic plates collision. Located in the Betic Cordillera, they can be considered as marginal Mediterranean basins that became gradually isolated during the Tortonian and Early Messinian due to tectonic uplift. Different evaporitic units accumulated in these basins during isolation and, in several cases, evaporitic conditions were associated to episodes of important organic matter accumulation. Results obtained from Late Tortonian to Early Messinian shales collected from boreholes, mines and outcrops in the internal Betic basins of Las Minas de Hellín, Cenajo and Socovos are presented. The organic matter was studied under fluorescence and scanning electron microscopy (SEM), and the main geochemical characteristics defined. They show a relation between organic-rich intervals with high potential of hydrocarbon generation, native sulfur, bio-induced dolomite and evaporitic deposits. These organicrich shales can be found before, during and after the evaporitic episodes. Results from the present study are compared with those previously obtained in the pre-evaporitic deposits of the Lorca Basin that showed high oil generation potential, a restricted-marine origin of the organic matter and a low degree of maturity. The occurrence of such potential source rocks in several basins points to a broad regional distribution. At a larger scale, in the Mediterranean Basin, organic-rich sediments were deposited before and during the Messinian Salinity Crisis. The studied examples could represent analogs for potential source rocks of the pre-Messinian salt play in the Western Mediterranean. (Author)

VET workers problem-solving skills in technology-rich environments: European approach

OpenAIRE

Hämäläinen, Raija

2014-01-01

The European workplace is challenging VET adults problem-solving skills in technology-rich environments (TREs). So far, no international large-scale assessment data has been available for VET. The PIAAC data comprise the most comprehensive source of information on adults skills to date. The present study (N=50 369) focuses on gaining insight into the problem-solving skills in TREs of adults with a VET background. When examining the similarities and differences in VET adults problem-solving sk...

VET workers’ problem-solving skills in technology-rich environments: European approach

OpenAIRE

Hämäläinen, Raija; Cincinnato, Sebastiano; Malin, Antero; De Wever, Bram

2014-01-01

The European workplace is challenging VET adults’ problem-solving skills in technology-rich environments (TREs). So far, no international large-scale assessment data has been available for VET. The PIAAC data comprise the most comprehensive source of information on adults’ skills to date. The present study (N=50 369) focuses on gaining insight into the problem-solving skills in TREs of adults with a VET background. When examining the similarities and differences in VET adults’ problem-solving...

V{sub 1+x}Nb{sub 1-x}IrB{sub 2} (x ∼ 0.1), the first quaternary metal-rich -boride adopting the Mo{sub 2}IrB{sub 2}-type structure: Synthesis, crystal and electronic structure and bonding analysis

Energy Technology Data Exchange (ETDEWEB)

Goerens, Christian; Fokwa, Boniface P.T. [Institute of Inorganic Chemistry, RWTH Aachen University (Germany)

2013-02-15

Polycrystalline samples and single crystals of the new metal-rich boride V{sub 1+x}Nb{sub 1-x}IrB{sub 2} (x ∼ 0.1), were synthesized by arc-melting the elements in a water-cooled copper crucible under an argon atmosphere and characterized by X-ray diffraction and EDX measurements. The crystal structure was refined on the basis of single crystal data. The new phase adopts the Mo{sub 2}IrB{sub 2}-type structure (space group Pnnm, no. 58) with the lattice parameters a = 7.301(7) Aa, b = 9.388(9) Aa and c = 3.206(5) Aa. It is the first quaternary representative of Mo{sub 2}IrB{sub 2}-type structure. The structure contains zigzag B{sub 4}-fragments with boron-boron distances of 1.83-1.85 Aa. The electronic density of states and crystal orbital Hamilton population (for bonding analysis) were calculated, using the linear muffin-tin orbital atomic sphere approximation (LMTO-ASA) method. According to these calculations, this metal-rich compound should be metallic, as expected. Furthermore, very strong boron-boron interactions are observed in the zigzag B{sub 4}-fragment and two significantly different Ir-B interactions are observed in the new phase and the prototype Mo{sub 2}IrB{sub 2}. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Electrolyte Engineering: Optimizing High-Rate Double-Layer Capacitances of Micropore- and Mesopore-Rich Activated Carbon.

Science.gov (United States)

Chen, Ting-Hao; Yang, Cheng-Hsien; Su, Ching-Yuan; Lee, Tai-Chou; Dong, Quan-Feng; Chang, Jeng-Kuei

2017-09-22

Various types of electrolyte cations as well as binary cations are used to optimize the capacitive performance of activated carbon (AC) with different pore structures. The high-rate capability of micropore-rich AC, governed by the mobility of desolvated cations, can outperform that of mesopore-rich AC, which essentially depends on the electrolyte conductivity. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Structural characteristics of proposed ITER [International Thermonuclear Experimental Reactor] TF [toroidal field] coil conductor

International Nuclear Information System (INIS)

Gibson, C.R.; Miller, J.R.

1988-01-01

This paper analyzes the effect of transverse loading on a cable-in-conduit conductor which has been proposed for the toroidal field coils of the International Thermonuclear Experimental Reactor. The primary components of this conductor are a loose cable of superconducting wires, a thin-wall tube for helium containment, and a U-shaped structural channel. A method is given where the geometry of this conductor can be optimized for a given set of operating conditions. It is shown, using finite-element modeling, that the structural channel is effective in supporting loads due to transverse forces and internal pressure. In addition, it is shown that the superconducting cable is effectively shielded from external transverse loads that might otherwise degrade its current carrying capacity. 10 refs., 10 figs., 3 tabs

Internal Structural Design of the Common Research Model Wing Box for Aeroelastic Tailoring

Science.gov (United States)

Jutte, Christine V.; Stanford, Bret K.; Wieseman, Carol D.

2015-01-01

This work explores the use of alternative internal structural designs within a full-scale wing box structure for aeroelastic tailoring, with a focus on curvilinear spars, ribs, and stringers. The baseline wing model is a fully-populated, cantilevered wing box structure of the Common Research Model (CRM). Metrics of interest include the wing weight, the onset of dynamic flutter, and the static aeroelastic stresses. Twelve parametric studies alter the number of internal structural members along with their location, orientation, and curvature. Additional evaluation metrics are considered to identify design trends that lead to lighter-weight, aeroelastically stable wing designs. The best designs of the individual studies are compared and discussed, with a focus on weight reduction and flutter resistance. The largest weight reductions were obtained by removing the inner spar, and performance was maintained by shifting stringers forward and/or using curvilinear ribs: 5.6% weight reduction, a 13.9% improvement in flutter speed, but a 3.0% increase in stress levels. Flutter resistance was also maintained using straight-rotated ribs although the design had a 4.2% lower flutter speed than the curved ribs of similar weight and stress levels were higher. For some configurations, the differences between curved and straight ribs were smaller, which provides motivation for future optimization-based studies to fully exploit the trade-offs.

STRUCTURAL ECONOMIC CHANGE AND INTERNATIONAL MIGRATION FROM MEXICO AND POLAND

Science.gov (United States)

Massey, Douglas S.; Kalter, Frank; Pren, Karen A.

2010-01-01

In this article we use uniquely comparable data sets from two very different settings to examine how exogenous economic transformations affect the likelihood and selectivity of international out-migration. Specifically, we use data from the Mexican Migration Project to construct event history files predicting first U.S. trips from seven communities in the state of Veracruz, which until recently sent very few migrants abroad. Similarly, using data from the Polish Migration Project, we derive comparable event history files predicting first trips to Germany from four Polish communities, which also sent few migrants abroad before the 1980s. Our analyses suggest that the onset of structural adjustment in both places had a significant effect in raising the probability of international migration, even when controlling for a set of standard variables specified by other theories to influence migration propensity, such as the size of the binational income gap and various indicators of human and social capital. PMID:21765550

Imaging Internal Structure of Long Bones Using Wave Scattering Theory.

Science.gov (United States)

Zheng, Rui; Le, Lawrence H; Sacchi, Mauricio D; Lou, Edmond

2015-11-01

An ultrasonic wavefield imaging method is developed to reconstruct the internal geometric properties of long bones using zero-offset data acquired axially on the bone surface. The imaging algorithm based on Born scattering theory is implemented with the conjugate gradient iterative method to reconstruct an optimal image. In the case of a multilayered velocity model, ray tracing through a smooth medium is used to calculate the traveled distance and traveling time. The method has been applied to simulated and real data. The results indicate that the interfaces of the top cortex are accurately imaged and correspond favorably to the original model. The reconstructed bottom cortex below the marrow is less accurate mainly because of the low signal-to-noise ratio. The current imaging method has successfully recovered the top cortical layer, providing a potential tool to investigate the internal structures of long bone cortex for osteoporosis assessment. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Application of phase-contrast X-ray microtomography to study the internal structures of Rhodium prolixus

International Nuclear Information System (INIS)

Almeida, Andre P. de; Soares, Jose; Barroso, Regina C.; Braz, Delson; Cardoso, Simone C.; Garcia, Eloi S.; Azambuja, Patricia; Gonzalez, Marcelo S.

2011-01-01

The PhC-SR-μCT is a nondestructive technique that allows the microanatomical investigations and 3D images reconstructions within a short time. This technique performed in blood sucker, Rhodnius prolixus - one of the most important primary vectors of of Trypanosoma cruzi, ethiologic agent of Chagas' disease in Latin America and also the most well-know studied insect in terms of both physiology and vector-parasite interactions. However, little is known about the development and structure of its internal organs. The aim of this work is to provide a non-invasive option for studying the internal structures of the main vector of Chagas' disease, which should help to answer important questions concerning anatomy, development, structure and plasticity of insect in general. Three-dimensional rendering images can provide a detailed knowledge of the interior of the insect, which is crucial for a better understanding of its function and evolution. (author)

Understanding comorbidity among internalizing problems: Integrating latent structural models of psychopathology and risk mechanisms

Science.gov (United States)

Hankin, Benjamin L.; Snyder, Hannah R.; Gulley, Lauren D.; Schweizer, Tina H.; Bijttebier, Patricia; Nelis, Sabine; Toh, Gim; Vasey, Michael W.

2016-01-01

It is well known that comorbidity is the rule, not the exception, for categorically defined psychiatric disorders, and this is also the case for internalizing disorders of depression and anxiety. This theoretical review paper addresses the ubiquity of comorbidity among internalizing disorders. Our central thesis is that progress in understanding this co-occurrence can be made by employing latent dimensional structural models that organize both psychopathology as well as vulnerabilities and risk mechanisms and by connecting the multiple levels of risk and psychopathology outcomes together. Different vulnerabilities and risk mechanisms are hypothesized to predict different levels of the structural model of psychopathology. We review the present state of knowledge based on concurrent and developmental sequential comorbidity patterns among common discrete psychiatric disorders in youth, and then we advocate for the use of more recent bifactor dimensional models of psychopathology (e.g., p factor, Caspi et al., 2014) that can help to explain the co-occurrence among internalizing symptoms. In support of this relatively novel conceptual perspective, we review six exemplar vulnerabilities and risk mechanisms, including executive function, information processing biases, cognitive vulnerabilities, positive and negative affectivity aspects of temperament, and autonomic dysregulation, along with the developmental occurrence of stressors in different domains, to show how these vulnerabilities can predict the general latent psychopathology factor, a unique latent internalizing dimension, as well as specific symptom syndrome manifestations. PMID:27739389

Developing organizational structures for international marketing

OpenAIRE

Ioan Cucu

2002-01-01

International marketing represents marketing activities performed across national boundaries. The level of involvement in international marketing can range from casual exporting to globalization of markets. Although most firms adjust their marketing mixes for differences in target markets, some firms are able to standardize their marketing efforts worldwide

RILEM International Symposium on Materials and Joints in Timber Structures

CERN Document Server

Reinhardt, H-W; Garrecht, Harald

2014-01-01

This book contains the contributions from the RILEM International Symposium on Materials and Joints in Timber Structures that was held in Stuttgart, Germany from October 8 to 10, 2013. It covers recent developments in the materials and the joints used in modern timber structures. Regarding basic wooden materials, the contributions highlight the widened spectrum of products comprising cross-laminated timber, glulam and LVL from hardwoods and block glued elements. Timber concrete compounds, cement bonded wood composites and innovative light-weight constructions represent increasingly employed alternatives for floors, bridges and facades. With regard to jointing technologies, considerable advances in both mechanical connections and glued joints are presented. Self-tapping screws have created unprecedented options for reliable, strong as well as ductile joints and reinforcement technologies. Regarding adhesives, which constitute the basis of the jointing/laminating technology of modern timber products, extended o...

Homogenization of the internal structures of a reactor with the cooling fluid

Energy Technology Data Exchange (ETDEWEB)

Robbe, M.F. [CEA Saclay, SEMT, 91 - Gif sur Yvette (France); Bliard, F. [Socotec Industrie, Service AME, 78 - Montigny le Bretonneux (France)

2001-07-01

To take into account the influence of a structure net among a fluid flow, without modelling exactly the structure shape, a concept of ''equivalent porosity method'' was developed. The structures are considered as solid pores inside the fluid. The structure presence is represented by three parameters: a porosity, a shape coefficient and a pressure loss coefficient. The method was studied for an Hypothetical Core Disruptive Accident in a Liquid Metal Fast Breeder Reactor, but it can be applied to any problem involving fluid flow getting through a solid net. The model was implemented in the computer code CASTEM-PLEXUS and validated on an analytical shock tube test, simulating an horizontal slice of a schematic LMFBR in case of a HCDA (bubble at high pressure, liquid sodium and internal structures of the reactor). A short parametric study shows the influence of the porosity and the structure shape on the pressure wave impacting the shock tube bottom. These results were used to simulate numerically the HCDA mechanical effects in a small scale reactor mock-up. (author)

Homogenization of the internal structures of a reactor with the cooling fluid

International Nuclear Information System (INIS)

Robbe, M.F.; Bliard, F.

2001-01-01

To take into account the influence of a structure net among a fluid flow, without modelling exactly the structure shape, a concept of ''equivalent porosity method'' was developed. The structures are considered as solid pores inside the fluid. The structure presence is represented by three parameters: a porosity, a shape coefficient and a pressure loss coefficient. The method was studied for an Hypothetical Core Disruptive Accident in a Liquid Metal Fast Breeder Reactor, but it can be applied to any problem involving fluid flow getting through a solid net. The model was implemented in the computer code CASTEM-PLEXUS and validated on an analytical shock tube test, simulating an horizontal slice of a schematic LMFBR in case of a HCDA (bubble at high pressure, liquid sodium and internal structures of the reactor). A short parametric study shows the influence of the porosity and the structure shape on the pressure wave impacting the shock tube bottom. These results were used to simulate numerically the HCDA mechanical effects in a small scale reactor mock-up. (author)

Kings Today, Rich Tomorrow

DEFF Research Database (Denmark)

Fattoum, Asma

2013-01-01

This study investigates the King vs. Rich dilemma that founder-CEOs face at IPO. When undertaking IPO, founders face two options. They can either get rich, but then run the risk of losing the control over their firms; or they can remain kings by introducing defensive mechanisms, but this is likel...

Screening of ligands for the Ullmann synthesis of electron-rich diaryl ethers

Directory of Open Access Journals (Sweden)

Nicola Otto

2012-07-01

Full Text Available In the search for new ligands for the Ullmann diaryl ether synthesis, permitting the coupling of electron-rich aryl bromides at relatively low temperatures, 56 structurally diverse multidentate ligands were screened in a model system that uses copper iodide in acetonitrile with potassium phosphate as the base. The ligands differed largely in their performance, but no privileged structural class could be identified.

Characterization of Li-rich layered oxides by using transmission electron microscope

Directory of Open Access Journals (Sweden)

Hu Zhao

2017-07-01

Full Text Available Lithium-rich layered oxides (LrLOs deliver extremely high specific capacities and are considered to be promising candidates for electric vehicle and smart grid applications. However, the application of LrLOs needs further understanding of the structural complexity and dynamic evolution of monoclinic and rhombohedral phases, in order to overcome the issues including voltage decay, poor rate capability, initial irreversible capacity loss and etc. The development of aberration correction for the transmission electron microscope and concurrent progress in electron spectroscopy, have fueled rapid progress in the understanding of the mechanism of such issues. New techniques based on the transmission electron microscope are first surveyed, and the applications of these techniques for the study of the structure, migration of transition metal, and the activation of oxygen of LrLOs are then explored in detail, with a particular focus on the mechanism of voltage decay. Keywords: Lithium-ion battery, Transmission electron microscope, Lithium-rich layered oxide, Cathode material

Nuclear fast neutron reactor cooled by a liquid metal and of which internal structures are equipped with a thermal protection device

International Nuclear Information System (INIS)

Lemercier, G.; Lions, N.

1986-01-01

The internal structures of a nuclear fast neutron reactor are covered at least partially, on the most hot side, by a thermal protection device. This device comprises modular plates arranged end to end with a certain play between themselves and taking approximately the shape of the internal structures. Each plate is fixed in its center on the internal structures by a stud. A small plate fixed at one of the corners of each plate and covering partially the adjacent plates ensures the safety fixing of these ones [fr

India's energy needs and areas of international cooperation

Energy Technology Data Exchange (ETDEWEB)

Wazir, S. N.

1980-03-15

India's energy position is poor because of relatively large imports of oil, and poor reserves. In the impending energy crisis, developing countries will suffer (whether or not it is oil-rich) unless international cooperation is forthcoming. Energy consumption patterns in India are shown in tables. Energy reserves are also analyzed, including nonconventional sources (geothermal, solar, etc.). Possible areas for international cooperation are explored. (DLC)

Corrosion Risk of Reinforced Concrete Structure Arising from Internal and External Chloride

Directory of Open Access Journals (Sweden)

M. J. Kim

2018-01-01

Full Text Available The corrosion risk of internal chloride and external chloride from three different exposure conditions was evaluated. The initiation of corrosion was detected by monitoring the galvanic current between cathode metal and embedded steel. The chloride threshold was determined by measuring the corrosion rate of steel by the polarization technique for internal chloride and the chloride profiling test for external chloride. As the result, the initiation of corrosion was accelerated with a cyclic wet/dry condition, compared to the totally wet condition. In addition, it was found that an increase of the drying ratio in the exposure condition resulted in an increase of corrosion rate after initiation. The threshold level of external chloride ranged from 0.2 to 0.3% weight by cement and internal chloride shows higher range, equated to 1.59–3.10%. Based on these data, the chloride penetration with exposure condition was predicted to determine the service life of reinforced concrete structure.

Internal oxidation of laminated ternary Ru–Ta–Zr coatings

Energy Technology Data Exchange (ETDEWEB)

Chen, Yung-I, E-mail: yichen@mail.ntou.edu.tw; Lu, Tso-Shen

2015-10-30

Highlights: • Internal oxidation was observed in annealed and laminated Ru–Ta–Zr coatings. • The oxidized Ru–Ta–Zr coatings comprised three alternately stacked sublayers. • Correlated variations of O{sup 2-} and Zr{sup 4+} binding energies were verified in XPS spectra. - Abstract: Researchers have observed the internal oxidation phenomenon in binary alloy coatings when developing refractory alloy coatings for protective purposes by conducting annealing at high temperatures and in oxygen-containing atmospheres. The coatings were assembled using cyclical gradient concentration deposition during cosputtering by employing a substrate holder rotating at a slow speed. The internally oxidized zone demonstrated a laminated structure, comprising alternating oxygen-rich and oxygen-deficient layers stacked in a general orientation. In the current study, Ru–Ta–Zr coatings were prepared with various stacking sequences during cosputtering. The Ru–Ta–Zr coatings were annealed at 600 °C in an atmosphere continuously purged with 1% O{sub 2}–99% Ar mixed gas for 30 min. A transmission electron microscope was used to examine the periods of the laminated layers and crystallinity of the annealed coatings. Depth profiles produced using an Auger electron spectroscope and X-ray photoelectron spectroscope were used to certify the periodic variation of the related constituents and chemical states of the elements, respectively. The results indicate that the internally oxidized ternary coatings are stacked of Ru-, Ta{sub 2}O{sub 5}-, and ZrO{sub 2}-dominant sublayers and that the stacking sequences of the sublayers affect the crystalline structure of the coatings. Zr is oxidized preferentially in the Ru–Ta–Zr coatings, increasing the surface hardness of the oxidized coatings.

An Eocene orthocone from Antarctica shows convergent evolution of internally shelled cephalopods

Science.gov (United States)

Bengtson, Stefan; Reguero, Marcelo A.; Mörs, Thomas

2017-01-01

Background The Subclass Coleoidea (Class Cephalopoda) accommodates the diverse present-day internally shelled cephalopod mollusks (Spirula, Sepia and octopuses, squids, Vampyroteuthis) and also extinct internally shelled cephalopods. Recent Spirula represents a unique coleoid retaining shell structures, a narrow marginal siphuncle and globular protoconch that signify the ancestry of the subclass Coleoidea from the Paleozoic subclass Bactritoidea. This hypothesis has been recently supported by newly recorded diverse bactritoid-like coleoids from the Carboniferous of the USA, but prior to this study no fossil cephalopod indicative of an endochochleate branch with an origin independent from subclass Bactritoidea has been reported. Methodology/Principal findings Two orthoconic conchs were recovered from the Early Eocene of Seymour Island at the tip of the Antarctic Peninsula, Antarctica. They have loosely mineralized organic-rich chitin-compatible microlaminated shell walls and broadly expanded central siphuncles. The morphological, ultrustructural and chemical data were determined and characterized through comparisons with extant and extinct taxa using Scanning Electron Microscopy/Energy Dispersive Spectrometry (SEM/EDS). Conclusions/Significance Our study presents the first evidence for an evolutionary lineage of internally shelled cephalopods with independent origin from Bactritoidea/Coleoidea, indicating convergent evolution with the subclass Coleoidea. A new subclass Paracoleoidea Doguzhaeva n. subcl. is established for accommodation of orthoconic cephalopods with the internal shell associated with a broadly expanded central siphuncle. Antarcticerida Doguzhaeva n. ord., Antarcticeratidae Doguzhaeva n. fam., Antarcticeras nordenskjoeldi Doguzhaeva n. gen., n. sp. are described within the subclass Paracoleoidea. The analysis of organic-rich shell preservation of A. nordenskjoeldi by use of SEM/EDS techniques revealed fossilization of hyposeptal cameral soft tissues

Structural contingency theory and individual differences: examination of external and internal person-team fit.

Science.gov (United States)

Hollenbeck, John R; Moon, Henry; Ellis, Aleksander P J; West, Bradley J; Ilgen, Daniel R; Sheppard, Lori; Porter, Christopher O L H; Wagner, John A

2002-06-01

This article develops and tests a structurally based, integrated theory of person-team fit. The theory developed is an extension of structural contingency theory and considers issues of external fit simultaneously with its examination of internal fit at the team level. Results from 80 teams working on an interdependent team task indicate that divisional structures demand high levels of cognitive ability on the part of teammembers. However, the advantages of high cognitive ability in divisional structures are neutralized when there is poor external fit between the structure and the environment. Instead, emotional stability becomes a critical factor among teammembers when a divisional structure is out of alignment with its environment. Individual differences seem to play little or no role in functional structures, regardless of the degree of external fit.

EFFECT OF DEXTRAN-graft-POLYACRYLAMIDE INTERNAL STRUCTURE ON FLOCCULATION PROCESS PARAMETERS

International Nuclear Information System (INIS)

Bezugla, T.; Kutsevol, N.; Shyichuk, A.; Ziolkowska, D.

2008-01-01

Dextran-graft-Polyacrylamide copolymers (D-g-PAA) of brush-like architecture were tested as flocculation aids in the model kaolin suspensions. Due to expanded conformation the D-g-PAA copolymers are more effective flocculants than individual PAA with close molecular mass. The internal structure of D-g-PAA copolymers which is determined by number and length of grafted PAA chains, the distance between grafts, etc., has the significant influence on flocculation behavior of such polymers

Visualization of the internal structure of Didymosphenia geminata frustules using nano X-ray tomography

OpenAIRE

Zglobicka, Izabela; Li, Qiong; Gluch, Jürgen; Płocińska, Magdalena; Noga, Teresa; Dobosz, Romuald; Szoszkiewicz, Robert; Witkowski, Andrzej; Zschech, Ehrenfried; Kurzydłowski, Krzysztof J.

2017-01-01

For the first time, the three-dimensional (3D) internal structure of naturally produced Didymosphenia geminata frustules were nondestructively visualized at sub-100 nm resolution. The well-optimized hierarchical structures of these natural organisms provide insight that is needed to design novel, environmentally friendly functional materials. Diatoms, which are widely distributed in freshwater, seawater and wet soils, are well known for their intricate, siliceous cell walls called ?frustules?...

Book of abstracts of the 3rd International conference and the 3rd International School for young scientists Interaction of hydrogen isotopes with structural materials. IHISM-07

International Nuclear Information System (INIS)

2007-01-01

The book involves abstracts of presentations at the 3rd International Conference and the 3rd International School for Young Scientists Interaction of Hydrogen Isotopes with Structural Materials (IHISM-07). The activities of Russian and foreign scientific centers associated with the use of hydrogen isotopes in power engineering, national economy and basic research are considered. The presentations cover the following areas: kinetics and interaction between hydrogen isotopes and solids including effects of radiogenic helium accumulation, hydrides and hydride transformations; structural transformations and mechanical properties; equipment and research techniques [ru

Developments on RICH detectors

International Nuclear Information System (INIS)

Besson, P.; Bourgeois, P.

1996-01-01

The RICH (ring imaging Cherenkov) detector which is dedicated to Cherenkov radiation detection is described. An improvement made by replacing photo sensible vapor with solid photocathode is studied. A RICH detector prototype with a CsI photocathode has been built in Saclay and used with Saturne. The first results are presented. (A.C.)

Effect of bidirectional internal flow on fluid–structure interaction dynamics of conveying marine riser model subject to shear current

Directory of Open Access Journals (Sweden)

Zheng-Shou Chen

2012-03-01

Full Text Available This article presents a numerical investigation concerning the effect of two kinds of axially progressing internal flows (namely, upward and downward on fluid–structure interaction (FSI dynamics about a marine riser model which is subject to external shear current. The CAE technology behind the current research is a proposed FSI solution, which combines structural analysis software with CFD technology together. Efficiency validation for the CFD software was carried out first. It has been proved that the result from numerical simulations agrees well with the observation from relating model test cases in which the fluidity of internal flow is ignorable. After verifying the numerical code accuracy, simulations are conducted to study the vibration response that attributes to the internal progressive flow. It is found that the existence of internal flow does play an important role in determining the vibration mode (/dominant frequency and the magnitude of instantaneous vibration amplitude. Since asymmetric curvature along the riser span emerges in the case of external shear current, the centrifugal and Coriolis accelerations owing to up- and downward internal progressive flows play different roles in determining the fluid–structure interaction response. The discrepancy between them becomes distinct, when the velocity ratio of internal flow against external shear current is relatively high.

Structural Features Facilitating Tumor Cell Targeting and Internalization by Bleomycin and Its Disaccharide

Science.gov (United States)

2016-01-01

We have shown previously that the bleomycin (BLM) carbohydrate moiety can recapitulate the tumor cell targeting effects of the entire BLM molecule, that BLM itself is modular in nature consisting of a DNA-cleaving aglycone which is delivered selectively to the interior of tumor cells by its carbohydrate moiety, and that there are disaccharides structurally related to the BLM disaccharide which are more efficient than the natural disaccharide at tumor cell targeting/uptake. Because BLM sugars can deliver molecular cargoes selectively to tumor cells, and thus potentially form the basis for a novel antitumor strategy, it seemed important to consider additional structural features capable of affecting the efficiency of tumor cell recognition and delivery. These included the effects of sugar polyvalency and net charge (at physiological pH) on tumor cell recognition, internalization, and trafficking. Since these parameters have been shown to affect cell surface recognition, internalization, and distribution in other contexts, this study has sought to define the effects of these structural features on tumor cell recognition by bleomycin and its disaccharide. We demonstrate that both can have a significant effect on tumor cell binding/internalization, and present data which suggests that the metal ions normally bound by bleomycin following clinical administration may significantly contribute to the efficiency of tumor cell uptake, in addition to their characterized function in DNA cleavage. A BLM disaccharide-Cy5** conjugate incorporating the positively charged dipeptide d-Lys-d-Lys was found to associate with both the mitochondria and the nuclear envelope of DU145 cells, suggesting possible cellular targets for BLM disaccharide–cytotoxin conjugates. PMID:25905565

Effects of Management on Lichen Species Richness, Ecological Traits and Community Structure in the Rodnei Mountains National Park (Romania).

Science.gov (United States)

Ardelean, Ioana Violeta; Keller, Christine; Scheidegger, Christoph

2015-01-01

Lichens are valuable bio-indicators for evaluating the consequences of human activities that are increasingly changing the earth's ecosystems. Since a major objective of national parks is the preservation of biodiversity, our aim is to analyse how natural resource management, the availability of lichen substrates and environmental parameters influence lichen diversity in Rodnei Mountains National Park situated in the Eastern Carpathians. Three main types of managed vegetation were investigated: the transhumance systems in alpine meadows, timber exploitation in mixed and pure spruce forests, and the corresponding conserved sites. The data were sampled following a replicated design. For the analysis, we considered not only all lichen species, but also species groups from different substrates such as soil, trees and deadwood. The lichen diversity was described according to species richness, red-list status and substrate-specialist species richness. The variation in species composition was related to the environmental variables. Habitat management was found to negatively influence species richness and alter the lichen community composition, particularly for threatened and substrate-specialist species. It reduced the mean level of threatened species richness by 59%, when all lichen species were considered, and by 81%, when only epiphytic lichens were considered. Management-induced disturbance significantly decreased lichen species richness in forest landscapes with long stand continuity. The diversity patterns of the lichens indicate a loss of species richness and change in species composition in areas where natural resources are still exploited inside the borders of the national park. It is thus imperative for protected areas, in particular old-growth forests and alpine meadows, to receive more protection than they have received in the past to ensure populations of the characteristic species remain viable in the future.

Effects of Management on Lichen Species Richness, Ecological Traits and Community Structure in the Rodnei Mountains National Park (Romania.

Directory of Open Access Journals (Sweden)

Ioana Violeta Ardelean

Full Text Available Lichens are valuable bio-indicators for evaluating the consequences of human activities that are increasingly changing the earth's ecosystems. Since a major objective of national parks is the preservation of biodiversity, our aim is to analyse how natural resource management, the availability of lichen substrates and environmental parameters influence lichen diversity in Rodnei Mountains National Park situated in the Eastern Carpathians. Three main types of managed vegetation were investigated: the transhumance systems in alpine meadows, timber exploitation in mixed and pure spruce forests, and the corresponding conserved sites. The data were sampled following a replicated design. For the analysis, we considered not only all lichen species, but also species groups from different substrates such as soil, trees and deadwood. The lichen diversity was described according to species richness, red-list status and substrate-specialist species richness. The variation in species composition was related to the environmental variables. Habitat management was found to negatively influence species richness and alter the lichen community composition, particularly for threatened and substrate-specialist species. It reduced the mean level of threatened species richness by 59%, when all lichen species were considered, and by 81%, when only epiphytic lichens were considered. Management-induced disturbance significantly decreased lichen species richness in forest landscapes with long stand continuity. The diversity patterns of the lichens indicate a loss of species richness and change in species composition in areas where natural resources are still exploited inside the borders of the national park. It is thus imperative for protected areas, in particular old-growth forests and alpine meadows, to receive more protection than they have received in the past to ensure populations of the characteristic species remain viable in the future.

Magnesium-Based Sacrificial Anode Cathodic Protection Coatings (Mg-Rich Primers for Aluminum Alloys

Directory of Open Access Journals (Sweden)

Michael D. Blanton

2012-09-01

Full Text Available Magnesium is electrochemically the most active metal employed in common structural alloys of iron and aluminum. Mg is widely used as a sacrificial anode to provide cathodic protection of underground and undersea metallic structures, ships, submarines, bridges, decks, aircraft and ground transportation systems. Following the same principle of utilizing Mg characteristics in engineering advantages in a decade-long successful R&D effort, Mg powder is now employed in organic coatings (termed as Mg-rich primers as a sacrificial anode pigment to protect aerospace grade aluminum alloys against corrosion. Mg-rich primers have performed very well on aluminum alloys when compared against the current chromate standard, but the carcinogenic chromate-based coatings/pretreatments are being widely used by the Department of Defense (DoD to protect its infrastructure and fleets against corrosion damage. Factors such as reactivity of Mg particles in the coating matrix during exposure to aggressive corrosion environments, interaction of atmospheric gases with Mg particles and the impact of Mg dissolution, increases in pH and hydrogen gas liberation at coating-metal interface, and primer adhesion need to be considered for further development of Mg-rich primer technology.

Photoconduction in silicon rich oxide films

Energy Technology Data Exchange (ETDEWEB)

Luna-Lopez, J A; Carrillo-Lopez, J; Flores-Gracia, F J; Garcia-Salgado, G [CIDS-ICUAP, Benemerita Universidad Autonoma de Puebla. Ed. 103 D and C, col. San Manuel, Puebla, Pue. Mexico 72570 (Mexico); Aceves-Mijares, M; Morales-Sanchez, A, E-mail: jluna@buap.siu.m, E-mail: jluna@inaoep.m [INAOE, Luis Enrique Erro No. 1, Apdo. 51, Tonantzintla, Puebla, Mexico 72000 (Mexico)

2009-05-01

Photoconduction of silicon rich oxide (SRO) thin films were studied by current-voltage (I-V) measurements, where ultraviolet (UV) and white (Vis) light illumination were applied. SRO thin films were deposited by low pressure chemical vapour deposition (LPCVD) technique, using SiH{sub 4} (silane) and N{sub 2}O (nitrous oxide) as reactive gases at 700 {sup 0}. The gas flow ratio, Ro = [N{sub 2}O]/[SiH{sub 4}] was used to control the silicon excess. The thickness and refractive index of the SRO films were 72.0 nm, 75.5 nm, 59.1 nm, 73.4 nm and 1.7, 1.5, 1.46, 1.45, corresponding to R{sub o} = 10, 20, 30 and 50, respectively. These results were obtained by null ellipsometry. Si nanoparticles (Si-nps) and defects within SRO films permit to obtain interesting photoelectric properties as a high photocurrent and photoconduction. These effects strongly depend on the silicon excess, thickness and structure type. Two different structures (Al/SRO/Si and Al/SRO/SRO/Si metal-oxide-semiconductor (MOS)-like structures) were fabricated and used as devices. The photocurrent in these structures is dominated by the generation of carriers due to the incident photon energies ({approx}3.0-1.6 eV and 5 eV). These structures showed large photoconductive response at room temperature. Therefore, these structures have potential applications in optoelectronics devices.

Magma-poor vs. magma-rich continental rifting and breakup in the Labrador Sea

Science.gov (United States)

Gouiza, M.; Paton, D.

2017-12-01

Magma-poor and magma-rich rifted margins show distinct structural and stratigraphic geometries during the rift to breakup period. In magma-poor margins, crustal stretching is accommodated mainly by brittle faulting and the formation of wide rift basins shaped by numerous graben and half-graben structures. Continental breakup and oceanic crust accretion are often preceded by a localised phase of (hyper-) extension where the upper mantle is embrittled, serpentinized, and exhumed to the surface. In magma-rich margins, the rift basin is narrow and extension is accompanied by a large magmatic supply. Continental breakup and oceanic crust accretion is preceded by the emplacement of a thick volcanic crust juxtaposing and underplating a moderately thinned continental crust. Both magma-poor and magma-rich rifting occur in response to lithospheric extension but the driving forces and processes are believed to be different. In the former extension is assumed to be driven by plate boundary forces, while in the latter extension is supposed to be controlled by sublithospheric mantle dynamics. However, this view fails in explaining observations from many Atlantic conjugate margins where magma-poor and magma-rich segments alternate in a relatively abrupt fashion. This is the case of the Labrador margin where the northern segment shows major magmatic supply during most of the syn-rift phase which culminate in the emplacement of a thick volcanic crust in the transitional domain along with high density bodies underplating the thinned continental crust; while the southern segment is characterized mainly by brittle extension, mantle seprentinization and exhumation prior to continental breakup. In this work, we use seismic and potential field data to describe the crustal and structural architectures of the Labrador margin, and investigate the tectonic and mechanical processes of rifting that may have controlled the magmatic supply in the different segments of the margin.

Robust Optical Richness Estimation with Reduced Scatter

Energy Technology Data Exchange (ETDEWEB)

Rykoff, E.S.; /LBL, Berkeley; Koester, B.P.; /Chicago U. /Chicago U., KICP; Rozo, E.; /Chicago U. /Chicago U., KICP; Annis, J.; /Fermilab; Evrard, A.E.; /Michigan U. /Michigan U., MCTP; Hansen, S.M.; /Lick Observ.; Hao, J.; /Fermilab; Johnston, D.E.; /Fermilab; McKay, T.A.; /Michigan U. /Michigan U., MCTP; Wechsler, R.H.; /KIPAC, Menlo Park /SLAC

2012-06-07

Reducing the scatter between cluster mass and optical richness is a key goal for cluster cosmology from photometric catalogs. We consider various modifications to the red-sequence matched filter richness estimator of Rozo et al. (2009b), and evaluate their impact on the scatter in X-ray luminosity at fixed richness. Most significantly, we find that deeper luminosity cuts can reduce the recovered scatter, finding that {sigma}{sub ln L{sub X}|{lambda}} = 0.63 {+-} 0.02 for clusters with M{sub 500c} {approx}> 1.6 x 10{sup 14} h{sub 70}{sup -1} M{sub {circle_dot}}. The corresponding scatter in mass at fixed richness is {sigma}{sub ln M|{lambda}} {approx} 0.2-0.3 depending on the richness, comparable to that for total X-ray luminosity. We find that including blue galaxies in the richness estimate increases the scatter, as does weighting galaxies by their optical luminosity. We further demonstrate that our richness estimator is very robust. Specifically, the filter employed when estimating richness can be calibrated directly from the data, without requiring a-priori calibrations of the red-sequence. We also demonstrate that the recovered richness is robust to up to 50% uncertainties in the galaxy background, as well as to the choice of photometric filter employed, so long as the filters span the 4000 {angstrom} break of red-sequence galaxies. Consequently, our richness estimator can be used to compare richness estimates of different clusters, even if they do not share the same photometric data. Appendix A includes 'easy-bake' instructions for implementing our optimal richness estimator, and we are releasing an implementation of the code that works with SDSS data, as well as an augmented maxBCG catalog with the {lambda} richness measured for each cluster.

Experiences and Challenges of International Students in Technology-Rich Learning Environments

Science.gov (United States)

Habib, Laurence; Johannesen, Monica; Øgrim, Leikny

2014-01-01

This article presents a study of international students and their use of technology in a Scandinavian institution of Higher Education. A special emphasis is placed on patterns of use of a virtual learning environment (VLE) that is available to all the study programmes at the institution. Actor-Network Theory (ANT) is used as a theoretical approach…

Effect of internal structure of collagen/hydroxyapatite scaffold on the osteogenic differentiation of mesenchymal stem cells.

Science.gov (United States)

Chen, Guobao; Lv, Yonggang; Dong, Chanjuan; Yang, Li

2015-01-01

Consisting of seed cells and scaffold, regenerative medicine provides a new way for the repair and regeneration of tissue and organ. Collagen/hydroxyapatite (HA) biocomposite scaffold is highlighted due to its advantageous features of two major components of bone matrix: collagen and HA. The aim of this study is to investigate the effect of internal structure of collagen/HA scaffold on the fate of rat mesenchymal stem cells (MSCs). The internal structure of collagen/HA scaffold was characterized by micro-CT. It is found that the porosity decreased while average compressive modulus increased with the increase of collagen proportion. Within the collagen proportion of 0.35%, 0.5% and 0.7%, the porosities were 89.08%, 78.37% and 75.36%, the pore sizes were 140.6±75.5 μm, 133.9±48.4 μm and 160.7±119.6 μm, and the average compressive moduli were 6.74±1.16 kPa, 8.82±2.12 kPa and 23.61±8.06 kPa, respectively. Among these three kinds of scaffolds, MSCs on the Col 0.35/HA 22 scaffold have the highest viability and the best cell proliferation. On the contrary, the Col 0.7/HA 22 scaffold has the best ability to stimulate MSCs to differentiate into osteoblasts in a relatively short period of time. In vivo research also demonstrated that the internal structure of collagen/HA scaffold has significant effect on the cell infiltration. Therefore, precise control of the internal structure of collagen/HA scaffold can provide a more efficient carrier to the repair of bone defects.

Conservation and Biodiversity of Rich Fens

DEFF Research Database (Denmark)

Andersen, Dagmar Kappel

2014-01-01

Rich fen is a habitat type dependent on a constant supply of nutrient poor, calcium rich groundwater. A high, stable groundwater table, relatively high pH combined with nutrient poor conditions support a special and very species rich vegetation including many rare and threatened plant species. In...

Application of phase-contrast X-ray microtomography to study the internal structures of Rhodium prolixus

Energy Technology Data Exchange (ETDEWEB)

Almeida, Andre P. de; Soares, Jose; Barroso, Regina C. [State University of Rio de Janeiro (UERJ), RJ (Brazil). Physics Institute; Braz, Delson, E-mail: delson@lin.ufrj.b [Federal University of Rio de Janeiro (COPPE/UFRJ), RJ (Brazil). Nuclear Engineering Program; Cardoso, Simone C., E-mail: simone@if.ufrj.b [Federal University of Rio de Janeiro (IF/UFRJ), RJ (Brazil). Physics Institute; Garcia, Eloi S.; Azambuja, Patricia [Oswaldo Cruz Institute (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Lab. of Biochemistry and Physiology of Insects; Gonzalez, Marcelo S. [Federal University Fluminense (UFF), Niteroi, RJ (Brazil). Dept. of General Biology

2011-07-01

The PhC-SR-{mu}CT is a nondestructive technique that allows the microanatomical investigations and 3D images reconstructions within a short time. This technique performed in blood sucker, Rhodnius prolixus - one of the most important primary vectors of of Trypanosoma cruzi, ethiologic agent of Chagas' disease in Latin America and also the most well-know studied insect in terms of both physiology and vector-parasite interactions. However, little is known about the development and structure of its internal organs. The aim of this work is to provide a non-invasive option for studying the internal structures of the main vector of Chagas' disease, which should help to answer important questions concerning anatomy, development, structure and plasticity of insect in general. Three-dimensional rendering images can provide a detailed knowledge of the interior of the insect, which is crucial for a better understanding of its function and evolution. (author)

Effect of pulse electron beam characteristics on internal friction and structural alterations in epoxy

International Nuclear Information System (INIS)

Zaikin, Yu.A.; Ismailova, G.A.; Al-Sheikhly, M.

2007-01-01

Temperature dependence of internal friction is experimentally studied in epoxy irradiated by 2.5 MeV pulse electron beam to different doses. Time dependence of internal friction characteristics associated with radiation-induced processes of polymer scission and cross-linking is analyzed and discussed. Experimental data on kinetics of structural transformations in epoxy are interpreted on the base of analytical solutions of differential equations for free radical accumulation during and after irradiation subject to the pulse irradiation mode and an arbitrary effective order of radical recombination

Decay Study for the very Neutron-Rich Sn Nuclides, $^{135-140}$Sn Separated by Selective Laser Ionization

CERN Multimedia

2002-01-01

%IS378 %title\\\\ \\\\ In this investigation, we wish to take advantage of chemically selective laser ionization to separate the very-neutron-rich Sn nuclides and determine their half-lives and delayed-neutron branches (P$_{n}$) using the Mainz $^{3}$He-delayed neutron spectrometer and close-geometry $\\gamma$-ray spectroscopy system. The $\\beta$-decay rates are dependent on a number of nuclear structure factors that may not be well described by models of nuclear structure developed for nuclides near stability. Determination of these decay properties will provide direct experimental data for r-process calculations and test the large number of models of nuclear structure for very-neutron rich Sn nuclides now in print.

Short-Term International Internship Experiences for Future Teachers and Other Child Development Professionals

Science.gov (United States)

Miller, Kari Knutson; Gonzalez, Amber M.

2016-01-01

This paper examines outcomes associated with participation in short-term, international internship experiences. Results suggest short-term international internship experiences contribute to rich personal and professional development outcomes. Findings highlight participant challenges associated with initial internship experiences, professional…

Using structural equation modelling to integrate human resources with internal practices for lean manufacturing implementation

Directory of Open Access Journals (Sweden)

Protik Basu

2018-01-01

Full Text Available The purpose of this paper is to explore and integrate the role of human resources with the internal practices of the Indian manufacturing industries towards successful implementation of lean manu-facturing (LM. An extensive literature survey is carried out. An attempt is made to build an ex-haustive list of all the input manifests related to human resources and internal practices necessary for LM implementation, coupled with a similar exhaustive list of the benefits accrued from its suc-cessful implementation. A structural model is thus conceptualized, which is empirically validated based on the data from the Indian manufacturing sector. Hardly any survey based empirical study in India has been found to integrate human resources with the internal processes towards success-ful LM implementation. This empirical research is thus carried out in the Indian manufacturing in-dustries. The analysis reveals six key input constructs and three output constructs, indicating that these constructs should act in unison to maximize the benefits of implementing lean. The structural model presented in this paper may be treated as a guide to integrate human resources with internal practices to successfully implement lean, leading to an optimum utilization of resources. This work is one of the very first researches to have a survey-based empirical analysis of the role of human resources and internal practices of the Indian manufacturing sector towards an effective lean im-plementation.

Research into the Energy Output of Asymmetric Cylindrical Structure under Internal Explosion Loading

Directory of Open Access Journals (Sweden)

Liangliang Ding

2018-04-01

Full Text Available The energy output characteristic of an asymmetric cylindrical structure under internal explosion loading has significant research value in the field of the national defense industry. This paper took the D-shaped structure as the research object. Three groups of experiments (D-90°, D-120°, D-150° were carried out. The D-shaped structure showed that fragments are concentrated in the middle and are sparse on both sides. Moreover, the fragment density decreased with the increase of the azimuth angle. The fragment velocities, which were measured from high-speed photography and an oscilloscope, coincided well with each other, and decreased with an increase in the central angle. Compared with the cylindrical structure, the fragment energy gain of the D-shaped structure is significant; the total energy and energy density of the three D-shaped structures were very close to each other. This indicates that D-120° is the optimal solution among the three D-shaped structures and it can provide guidance for the future design of D-shaped structures to achieve higher energy output.

Local richness along gradients in the Siskiyou herb flora: R.H. Whittaker revisited

Science.gov (United States)

Grace, James B.; Harrison, Susan; Damschen, Ellen Ingman

2011-01-01

In his classic study in the Siskiyou Mountains (Oregon, USA), one of the most botanically rich forested regions in North America, R. H. Whittaker (1960) foreshadowed many modern ideas on the multivariate control of local species richness along environmental gradients related to productivity. Using a structural equation model to analyze his data, which were never previously statistically analyzed, we demonstrate that Whittaker was remarkably accurate in concluding that local herb richness in these late-seral forests is explained to a large extent by three major abiotic gradients (soils, topography, and elevation), and in turn, by the effects of these gradients on tree densities and the numbers of individual herbs. However, while Whittaker also clearly appreciated the significance of large-scale evolutionary and biogeographic influences on community composition, he did not fully articulate the more recent concept that variation in the species richness of local communities could be explained in part by variation in the sizes of regional species pools. Our model of his data is among the first to use estimates of regional species pool size to explain variation in local community richness along productivity-related gradients. We find that regional pool size, combined with a modest number of other interacting abiotic and biotic factors, explains most of the variation in local herb richness in the Siskiyou biodiversity hotspot.

Dissecting the polysaccharide-rich grape cell wall matrix using recombinant pectinases during winemaking

DEFF Research Database (Denmark)

Gao, Yu; Fangel, Jonatan Ulrik; Willats, William George Tycho

2016-01-01

different combinations of purified recombinant pectinases with cell wall profiling tools to follow the deconstruction process during winemaking. Multivariate data analysis of the glycan microarray (CoMPP) and gas chromatography (GC) results revealed that pectin lyase performed almost as effectively in de......The effectiveness of enzyme-mediated-maceration in red winemaking relies on the use of an optimum combination of specific enzymes. A lack of information on the relevant enzyme activities and the corresponding polysaccharide-rich berry cell wall structure is a major limitation. This study used......-pectination as certain commercial enzyme mixtures. Surprisingly the combination of endo-polygalacturonase and pectin-methyl-esterase only unraveled the cell walls without de-pectination. Datasets from the various combinations used confirmed pectin-rich and xyloglucan-rich layers within the grape pomace. These data...

Examining the Dynamic Structure of Daily Internalizing and Externalizing Behavior at Multiple Levels of Analysis

Science.gov (United States)

Wright, Aidan G. C.; Beltz, Adriene M.; Gates, Kathleen M.; Molenaar, Peter C. M.; Simms, Leonard J.

2015-01-01

Psychiatric diagnostic covariation suggests that the underlying structure of psychopathology is not one of circumscribed disorders. Quantitative modeling of individual differences in diagnostic patterns has uncovered several broad domains of mental disorder liability, of which the Internalizing and Externalizing spectra have garnered the greatest support. These dimensions have generally been estimated from lifetime or past-year comorbidity patters, which are distal from the covariation of symptoms and maladaptive behavior that ebb and flow in daily life. In this study, structural models are applied to daily diary data (Median = 94 days) of maladaptive behaviors collected from a sample (N = 101) of individuals diagnosed with personality disorders (PDs). Using multilevel and unified structural equation modeling, between-person, within-person, and person-specific structures were estimated from 16 behaviors that are encompassed by the Internalizing and Externalizing spectra. At the between-person level (i.e., individual differences in average endorsement across days) we found support for a two-factor Internalizing–Externalizing model, which exhibits significant associations with corresponding diagnostic spectra. At the within-person level (i.e., dynamic covariation among daily behavior pooled across individuals) we found support for a more differentiated, four-factor, Negative Affect-Detachment-Hostility-Disinhibition structure. Finally, we demonstrate that the person-specific structures of associations between these four domains are highly idiosyncratic. PMID:26732546

Structural and isotopic analysis of kerogens in sediments rich in free sulfurised Botryococcus braunii biomarkers

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Grice, K.; Schouten, S.; Blokker, P.; Derenne, S.; Largeau, C.; Nissenbaum, A.

2003-01-01

Type I kerogens of two relatively immature, unusual hypersaline sediments [with extracts rich in sulfurised Botryococcus braunii (B. braunii) biomarkers] of Miocene/Pliocene age from the Sdom Formation (Dead Sea, Israel), have been investigated using a variety of organic geochemical techniques. Py

Contrasting magmatic structures between small plutons and batholiths emplaced at shallow crustal level (Sierras de Córdoba, Argentina)

Science.gov (United States)

Pinotti, Lucio P.; D'Eramo, Fernando J.; Weinberg, Roberto F.; Demartis, Manuel; Tubía, José María; Coniglio, Jorge E.; Radice, Stefania; Maffini, M. Natalia; Aragón, Eugenio

2016-11-01

Processes like injection, magma flow and differentiation and influence of the regional strain field are here described and contrasted to shed light on their role in the formation of small plutons and large batholiths their magmatic structures. The final geometric and compositional arrangement of magma bodies are a complex record of their construction and internal flow history. Magma injection, flow and differentiation, as well as regional stresses, all control the internal nature of magma bodies. Large magma bodies emplaced at shallow crustal levels result from the intrusion of multiple magma batches that interact in a variety of ways, depending on internal and external dynamics, and where the early magmatic, growth-related structures are commonly overprinted by subsequent history. In contrast, small plutons emplaced in the brittle-ductile transition more likely preserve growth-related structures, having a relatively simple cooling history and limited internal magma flow. Outcrop-scale magmatic structures in both cases record a rich set of complementary information that can help elucidate their evolution. Large and small granitic bodies of the Sierra Pampeanas preserve excellent exposures of magmatic structures that formed as magmas stepped through different rheological states during pluton growth and solidification. These structures reveal not only the flow pattern inside magma chambers, but also the rheological evolution of magmas in response to temperature evolution.

Co-ordination of the International Network of Nuclear Structure and Decay Data Evaluators

Energy Technology Data Exchange (ETDEWEB)

Ricard-McCutchan, E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Dimitriou, P. [Intl Atomic Energy Agency (IAEA), Vienna (Austria); Nichols, A. L. [Univ. of Surrey, Guildford (United Kingdom)

2015-08-01

The 21st meeting of the International Network of Nuclear Structure and Decay Data Evaluators was convened at the IAEA Headquarters, Vienna, from 20 to 24 April 2015 under the auspices of the IAEA Nuclear Data Section. This meeting was attended by 36 scientists from 15 Member States, plus IAEA staff, concerned with the compilation, evaluation and dissemination of nuclear structure and decay data. A summary of the meeting, data centre reports, various proposals considered, and actions agreed by the participants, as well as recommendations/conclusions are presented within this document.

More than a boundary shift: Perceptual adaptation to foreign-accented speech reshapes the internal structure of phonetic categories.

Science.gov (United States)

Xie, Xin; Theodore, Rachel M; Myers, Emily B

2017-01-01

The literature on perceptual learning for speech shows that listeners use lexical information to disambiguate phonetically ambiguous speech sounds and that they maintain this new mapping for later recognition of ambiguous sounds for a given talker. Evidence for this kind of perceptual reorganization has focused on phonetic category boundary shifts. Here, we asked whether listeners adjust both category boundaries and internal category structure in rapid adaptation to foreign accents. We investigated the perceptual learning of Mandarin-accented productions of word-final voiced stops in English. After exposure to a Mandarin speaker's productions, native-English listeners' adaptation to the talker was tested in 3 ways: a cross-modal priming task to assess spoken word recognition (Experiment 1), a category identification task to assess shifts in the phonetic boundary (Experiment 2), and a goodness rating task to assess internal category structure (Experiment 3). Following exposure, both category boundary and internal category structure were adjusted; moreover, these prelexical changes facilitated subsequent word recognition. Together, the results demonstrate that listeners' sensitivity to acoustic-phonetic detail in the accented input promoted a dynamic, comprehensive reorganization of their perceptual response as a consequence of exposure to the accented input. We suggest that an examination of internal category structure is important for a complete account of the mechanisms of perceptual learning. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The research rotation: competency-based structured and novel approach to research training of internal medicine residents

Directory of Open Access Journals (Sweden)

Dimitrov Vihren

2006-10-01

Full Text Available Abstract Background In the United States, the Accreditation Council of graduate medical education (ACGME requires all accredited Internal medicine residency training programs to facilitate resident scholarly activities. However, clinical experience and medical education still remain the main focus of graduate medical education in many Internal Medicine (IM residency-training programs. Left to design the structure, process and outcome evaluation of the ACGME research requirement, residency-training programs are faced with numerous barriers. Many residency programs report having been cited by the ACGME residency review committee in IM for lack of scholarly activity by residents. Methods We would like to share our experience at Lincoln Hospital, an affiliate of Weill Medical College Cornell University New York, in designing and implementing a successful structured research curriculum based on ACGME competencies taught during a dedicated "research rotation". Results Since the inception of the research rotation in 2004, participation of our residents among scholarly activities has substantially increased. Our residents increasingly believe and appreciate that research is an integral component of residency training and essential for practice of medicine. Conclusion Internal medicine residents' outlook in research can be significantly improved using a research curriculum offered through a structured and dedicated research rotation. This is exemplified by the improvement noted in resident satisfaction, their participation in scholarly activities and resident research outcomes since the inception of the research rotation in our internal medicine training program.

Gamma-ray spectroscopy of the neutron-rich Ni region through heavy-ion deep-inelastic collisions

International Nuclear Information System (INIS)

Ishii, T.; Asai, M.; Matsuda, M.; Ichikawa, S.; Makishima, A.; Hossain, I.; Kleinheinz, P.; Ogawa, M.

2002-01-01

Nuclei in the neutron-rich Ni region have been studied by γ-ray spectroscopy. Gamma-rays emitted from isomers, with T 1/2 >1 ns, produced in heavy-ion deep-inelastic collisions were measured with an isomer-scope. The nuclear structure of the doubly magic 68 Ni and its neighbor 69,71 Cu is discussed on the basis of the shell model. Future experiments for more neutron-rich Ni nuclei are also viewed. (orig.)

Gamma-ray spectroscopy of the neutron-rich Ni region through heavy-ion deep-inelastic collisions

Science.gov (United States)

Ishii, T.; Asai, M.; Makishima, A.; Hossain, I.; Kleinheinz, P.; Ogawa, M.; Matsuda, M.; Ichikawa, S.

Nuclei in the neutron-rich Ni region have been studied by γ-ray spectroscopy. Gamma-rays emitted from isomers, with T1/2 > 1 ns, produced in heavy-ion deep-inelastic collisions were measured with an isomer-scope. The nuclear structure of the doubly magic 68Ni and its neighbor 69,71Cu is discussed on the basis of the shell model. Future experiments for more neutron-rich Ni nuclei are also viewed.

Nonlocal transformation of the internal quantum particle structure

Directory of Open Access Journals (Sweden)

Alexey Yu. Samarin

2016-09-01

Full Text Available The analysis of the integral wave equation, having path integral kernel, has resulted, that collapse phenomenon is based on the nonlocal transformation of the internal structure of a quantum particle, considering in the form of the matter fields collection. This nonlocality allows to escape the contradiction between the reduction quantum mechanics postulate and special relativity. It is shown, that the wave function transformation, corresponding to von Neumann's reduction, has the deterministic nature and the quantum mechanics stochasticity is a consequence of a macroscopic measurer presence in the measuring process. Besides it is demonstrated, that the decogerence phenomenon has the same mechanism of the wave function transformation. EPR-type experiment is described in detail and the possibility of the faster-then light communication is proved, as well the possible rules of thumb of this communication are proposed.

Quantitative analysis and prediction of curvature in leucine-rich repeat proteins.

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Hindle, K Lauren; Bella, Jordi; Lovell, Simon C

2009-11-01

Leucine-rich repeat (LRR) proteins form a large and diverse family. They have a wide range of functions most of which involve the formation of protein-protein interactions. All known LRR structures form curved solenoids, although there is large variation in their curvature. It is this curvature that determines the shape and dimensions of the inner space available for ligand binding. Unfortunately, large-scale parameters such as the overall curvature of a protein domain are extremely difficult to predict. Here, we present a quantitative analysis of determinants of curvature of this family. Individual repeats typically range in length between 20 and 30 residues and have a variety of secondary structures on their convex side. The observed curvature of the LRR domains correlates poorly with the lengths of their individual repeats. We have, therefore, developed a scoring function based on the secondary structure of the convex side of the protein that allows prediction of the overall curvature with a high degree of accuracy. We also demonstrate the effectiveness of this method in selecting a suitable template for comparative modeling. We have developed an automated, quantitative protocol that can be used to predict accurately the curvature of leucine-rich repeat proteins of unknown structure from sequence alone. This protocol is available as an online resource at http://www.bioinf.manchester.ac.uk/curlrr/.

Estimating Rheological Parameters of Anhydrite from Folded Evaporite sequences: Implications for Internal Dynamics of Salt Structure

Science.gov (United States)

Adamuszek, Marta; Dabrowski, Marcin; Schmalholz, Stefan M.; Urai, Janos L.; Raith, Alexander

2015-04-01

Salt structures have been identified as a potential target for hydrocarbon, CO2, or radioactive waste storage. The most suitable locations for magazines are considered in the thick and relatively homogeneous rock salt layers. However, salt structures often consist of the evaporite sequence including rock salt intercalated with other rock types e.g.: anhydrite, gypsum, potassium and magnesium salt, calcite, dolomite, or shale. The presence of such heterogeneities causes a serious disturbance in the structure management. Detailed analysis of the internal architecture and internal dynamics of the salt structure are crucial for evaluating them as suitable repositories and also their long-term stability. The goal of this study is to analyse the influence of the presence of anhydrite layers on the internal dynamics of salt structures. Anhydrite is a common rock in evaporite sequences. Its physical and mechanical properties strongly differ from the properties of rock salt. The density of anhydrite is much higher than the density of salt, thus anhydrite is likely to sink in salt causing the disturbance of the surrounding structures. This suggestion was the starting point to the discussion about the long-term stability of the magazines in salt structures [1]. However, the other important parameter that has to be taken into account is the viscosity of anhydrite. The high viscosity ratio between salt and anhydrite can restrain the layer from sinking. The rheological behaviour of anhydrite has been studied in laboratory experiments [2], but the results only provide information about the short-term behaviour. The long-term behaviour can be best predicted using indirect methods e.g. based on the analysis of natural structures that developed over geological time scale. One of the most promising are fold structures, the shape of which is very sensitive to the rheological parameters of the deforming materials. Folds can develop in mechanically stratified materials during layer