bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on an Improved Plastic Bonded Explosive (PBX) for Shaped Charges
Authors: Samudre Samson S. , Nair Ushadevi R. , Gore Girish M. , Kumar Sinha Rabindra , Kanti Sikder Arun , Nandan Asthana Shri 
Published: April 2009

AbstractThis paper reports the characteristics and performance evaluation of a pressed plastic bonded explosive (PBX) composition based on hexanitrohexaazaisowurtzitane (HNIW, CL‐20) and polyurethane (PU) in comparison with PU‐coated cyclotetramethylene tetranitramine (HMX). PU‐coated compositions were prepared by slurry method. The processed CL‐20‐based composition exhibited a relatively higher sensitivity compared to that of the HMX composition. The measured velocity of detonation (VOD) of the CL‐20‐based composition was found to be higher than predicted. A theoretical approach was applied to assess the penetration capability of the CL‐20 formulation. Shaped charges of 32 mm caliber were prepared and penetration experiments were carried out at 37 mm standoff distance on mild steel blocks. The results established high penetration capability of CL‐20‐based formulation. An attempt was made to explain the trends obtained.
Dielectric dispersion study of Mn‐doped PLZT (8/65/35)
Authors: Mohiddon Md. Ahamad , Yadav K. L. 
Published: April 2009

AbstractMn‐modified Pb0.92La0.08(Zr0.65Ti0.35)O3 (PLZT) was prepared chemically by a coprecipitate method using their respective nitrate salts and isopropoxides. Differential thermal analysis (DTA) and X‐ray analysis clearly show the formation of PLZT single rhombohedral phase for samples calcined beyond 750 °C. Uniform grain distribution was observed from scanning electron microscopic (SEM) studies and grain size was found to increase with Mn doping up to x = 0.08 and then decreased. Dielectric measurement shows the decrease in peak transition temperature (TC) with Mn doping up to x = 0.12 and then increase along with a sharp rise in dielectric maxima. A diffuse dielectric dispersion is observed in all the compositions. A detailed dispersion study was carried out using the Vogel–Fulcher empirical relation, a universal relaxation law and the Havriliak–Negami function. The Vogel–Fulcher relation fitting parameters of activation energy and freezing temperature were found to decrease with Mn doping up to x = 0.12, which was expected to be the cause of the variation of TC. The exponent m of the universal relaxation law was found to increase with Mn doping and also with increasing temperature, which suggests an enhanced conducting nature of the composition. In the Havriliak–Negami function, the Cole–Cole fitting parameter α was found to increase and β was found to decrease with Mn doping and also with temperature, which suggests that the dispersion behavior changed from Cole–Cole type to Cole–Davidson type with Mn doping in PLZT. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Luminescence and structural properties of oxyorthosilicate and Al2O3 nanophosphors
Authors: Blair Michael W. , Jacobsohn Luiz G. , Bennett Bryan L. , Tornga Stephanie C. , Yukihara Eduardo G. , McKigney Edward A. , Muenchausen Ross E. 
Published: April 2009

AbstractA large amount of research has been conducted on semiconducting quantum dots exploring quantum confinement effects. On the other hand, nanophosphors – inorganic insulating nanostructured luminescent materials – have received considerably less attention. Our research involving nanomaterials has then focused on the question: How does reduced dimensionality affect the physical and chemical behaviour of nanophosphors? In order to partially answer this fundamental question, we have produced numerous oxides, among them Lu2SiO5:Ce (LSO), Y2SiO5:Ce (YSO), Gd2SIO5:Ce (GSO), and Al2O3, and characterized their structural and luminescent properties. Structure, grain size, phase purity and crystallite morphology were determined using X‐ray diffraction, transmission electron microscopy, and electron paramagnetic resonance. The luminescent properties of the nanophosphors were characterized by thermoluminescence, radioluminescence, photoluminescence, and optically stimulated luminescence. In this work, we will present an overview of the field of nanophosphors, and summarize the results obtained in our laboratory with particular emphasis on the luminescent properties. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Accounting for regression‐to‐the‐mean in tests for recent changes in institutional performance: Analysis and power
Authors: Jones Hayley E. , Spiegelhalter David J. 
Published: April 2009

AbstractRecent changes in individual units are often of interest when monitoring and assessing the performance of healthcare providers. We consider three high profile examples: (a) annual teenage pregnancy rates in English local authorities, (b) quarterly rates of the hospital‐acquired infection Clostridium difficile in National Health Service (NHS) Trusts and (c) annual mortality rates following heart surgery in New York State hospitals. Increasingly, government targets call for continual improvements, in each individual provider as well as overall.Owing to the well‐known statistical phenomenon of regression‐to‐the‐mean, observed changes between just two measurements are potentially misleading. This problem has received much attention in other areas, but there is a need for guidelines within performance monitoring.In this paper we show theoretically and with worked examples that a simple random effects predictive distribution can be used to ‘correct’ for the potentially undesirable consequences of regression‐to‐the‐mean on a test for individual change. We discuss connections to the literature in other fields, and build upon this, in particular by examining the effect of the correction on the power to detect genuine changes. It is demonstrated that a gain in average power can be expected, but that this gain is only very slight if the providers are very different from one another, for example due to poor risk adjustment. Further, the power of the corrected test depends on the provider's baseline rate and, although large gains can be expected for some providers, this is at the cost of some power to detect real changes in others. Copyright © 2009 John Wiley & Sons, Ltd.
Eine Methode zur Bewertung von Restspalten in Schweißnähten an T‐ und Kreuzstoßverbindungen
Authors: Feldmann Markus , Eichler Björn , Höhler Susanne 
Published: April 2009

AbstractEingeführte Normen verlangen von der Stahlbaufertigung den Nachweis einer vollständigen Durchschweißung bei Vollanschlüssen. Für die ausführenden Betriebe ist diese Forderung oft mit zeit‐ und kostenintensiven Reparaturschweißungen versehen.Bis vor kurzem fehlte eine Methode zur Klassifizierung und damit einhergehend eine Methode zur Tolerierung von nicht vollständigen Durchschweißungen (Restspalte), so dass teure Reparaturarbeiten vorprogrammiert waren.Im Rahmen eines von der Arbeitsgemeinschaft industrieller Forschungsvereinigungen AiF über den Deutschen Ausschuss für Stahlbau DASt geförderten Projektes [1] wurde die Grundlage eines Beurteilungskonzeptes geschaffen, das bei hinreichend genauer Detektierung eines Restspaltes durch ein zerstörungsfreies Prüfverfahren und unter Einhaltung der im Stahlbau geforderten Bauteilsicherheit gewährleistet, dass eine nach aktueller Normensituation ungenügende Durchschweißung im Bauteil belassen werden kann. Mit Hilfe bruchmechanischer Methoden kann so für nicht vollständig durchschweißte HY‐ bzw. DHY‐Nähte an Kreuz‐ und T‐Stößen eine ausreichende Tragfähigkeit nachgewiesen und sprödes Versagen der Verbindung ausgeschlossen werden, und zwar sowohl für ruhende als auch für zyklische Beanspruchungen.
Zuschriften zu: Naumes, J., Strohmann, I., Ungermann, D., Sedlacek, G.: Die neuen Stabilitätsnachweise im Stahlbau nach Eurocode 3
Authors: Naumes Johannes , Strohmann Isabel , Ungermann Dieter , Sedlacek Gerhard 
Published: April 2009

Abstract[Stahlbau 77 (2008), H. 10, S. 748–761 ]
Short soft x‐ray sources
Authors: Siciliano M.V. , Lorusso A. , Velardi L. , Nassisi V. 
Published: April 2009

AbstractIn this work we report on the characterization of pulsed soft x‐rays emitted from laser‐produced plasma. The plasma was generated by a pulsed KrF excimer laser focused on pure Si, Cu and Ta targets by 40, 80 and 120 mJ laser energies. The utilized detector was a very sensitive Faraday cup which opportunely biased was able to record time‐resolved signals of x‐rays and to estimate their energy. The found x‐rays energy values were compared with the ion temperature of the plasma obtained by fitting the time‐resolved ion current signals with a shifted Maxwell‐Boltzmann velocity distribution. The results showed that the laser‐produced Ta plasma induced bunches of x‐rays having in average the highest energy values and it was also characterized by ion temperature higher than the ones of the laser‐produced Si and Cu plasmas. Copyright © 2009 John Wiley & Sons, Ltd.
Practitioner expertise: Creating quality within the daily tumble of events in youth settings
Authors: Larson Reed W. , Rickman Aimee N. , Gibbons Colleen M. , Walker Kathrin C. 
Published: April 2009

AbstractPractitioners in youth settings experience life on the ground as a tumble of events, shaped by a confluence of youth needs, institutional expectations, and other inputs. The quality of the setting is determined in part by practitioners' expertise in shaping and responding to these events. The situations that arise in practice, and how staff respond, can be turning points, good or bad, in youths' experience of the setting. They can also be opportunities for youth development. This article examines the wide‐ranging events, situations, or “dilemmas of practice” that occur in the daily life of youth development programs. Research shows that these varied situations are shaped by the ecology of diverse people and systems that influence the setting. They involve considerations that may entail everything from the psychology of different youth, to how parents from a cultural group think, to the dynamics of government systems. Expert youth practitioners, it is found, are able to identify more considerations than novices in these situations, and they possess a wider repertoire of responses. They also formulate more responses that are youth centered and address multiple considerations. Expertise involves being able to balance diverse concerns, including how to create and sustain conditions for the development of young people. Researchers can contribute by helping us better understand this array of situations and how experts respond. Improvement in the quality of youth settings can be achieved through greater knowledge of the tumble of events that occur and by helping train practitioners in skills for responding to it.
On the Crystal Chemistry of Oxometallates of Thorium
Authors: Müller‐Buschbaum Hanskarl 
Published: April 2009

AbstractThe crystal chemistry of the valence stable Thorium (Th4+) shows in oxovanadates, ‐niobates, ‐molybdates, ‐tantalates etc. typical cationic property. It depends on the big size of the Th4+ ion in the order of r(Th4+) = 0.92 Å (C.N. = 6) up to r(Th4+) = 1.34 Å (C.N. = 12), comparable with the radii of alkaline and alkaline earth metals: r(Na+) = 1.02 Å (C.N. = 6) or r(K+) = 1.5 Å (C.N. = 8); r(Ca2+/Sr2+) = 1.1 Å/1.26 Å (C.N. = 8). There exists only one typical compound that may be of the oxothorate type with the composition NaK3Th2O6. Na+ and K+ can be declared to be components of the cationic part of the crystal structure. In contrary, thorium and oxygen are common components of the anionic part of the crystal structure. From the point of view of the shared polyhedra (exclusively octahedra), NaK3Th2O6 belongs to the thorium‐oxometallates too. The report on oxometallates of thorium shows compounds with one, two, four and five Th4+ atoms in combination with V5+, Nb5+, Ta5+ and Mo6+. W6+ is completely missing. Some of the Tantalates belong to the Jahnberg compounds, showing planar nets of corner shared pentagonal bipyramids. ThMO4 and cationic mixed compounds, Th1–xAxMO4, crystallize with the Scheelite (respectively Huttonite) structure and at least Th4+ is part of ordered and disordered perowskites showing more or less deviations from the cubic symmetry.
Distance decay of community dynamics in rocky intertidal sessile assemblages evaluated by transition matrix models
Authors: Tsujino Masahiro , Hori Masakazu , Okuda Takehiro , Nakaoka Masahiro , Yamamoto Tomoko , Noda Takashi 
Published: April 2009

AbstractIt is well known that the similarity in species composition between two communities decays with the geographic distance that separates them. It is thus likely that the similarity in the dynamics of two communities also decays with distance, because the distance–decay relationship is fundamental in nature. However, the distance–decay relationships of community dynamics have not yet been revealed. We used transition matrix models to evaluate distance–decay relationships of seasonal community dynamics (from spring to summer) in rocky intertidal sessile assemblages along the Pacific coast of Japan between 31°N and 43°N. We evaluated the distance–decay relationships of whole‐community dynamics and of three dynamics‐related components—recruitment, disturbance, and species interaction (competition and facilitation)—for communities separated by distances ranging from several meters to thousands of kilometers. The similarity of the recruitment dynamics among communities declined rapidly with distance within the fine spatial scale, but only moderately within larger scales. The similarity of the disturbance dynamics was independent of distance, and the similarity of species interaction declined slightly with increasing distance. The similarity of whole‐community dynamics declined rapidly with distance at a fine spatial scale and moderately at larger scales. The fact that the distance–decay relationship of whole‐community dynamics was similar to that of recruitment may suggest that recruitment processes are the most important determinant of spatial variability of community dynamics at our study sites during the study period.
Temporal and size-related variation in the diet, consumption rate, and daily ration of mackerel tuna (Euthynnus affinis) in neritic waters of eastern Australia
Authors: Griffiths Shane P. , Kuhnert Petra M. , Fry Gary F. , Manson Fiona J. 
Published: April 2009

AbstractGriffiths, S. P., Kuhnert, P. M., Fry, G. F., and Manson, F. J. 2009. Temporal and size-related variation in the diet, consumption rate, and daily ration of mackerel tuna (Euthynnus affinis) in neritic waters of eastern Australia. – ICES Journal of Marine Science, 66: 720–733. The diet, food consumption, and ration of mackerel tuna (Euthynnus affinis) were studied in Australian neritic waters. Overall, 43 prey taxa were identified from 271 stomachs. The diet was primarily pelagic clupeoids (78% by wet weight, WW; 71% by frequency of occurrence, FO) and demersal fish (19% WW; 32% FO). Multivariate regression tree analysis revealed that temporal differences, followed by fish size, explained most of the variation in the diet composition. Autumn diets differed from those in other seasons because tuna ate virtually only engraulids then. During other seasons, engraulids were still the dominant taxon in the diet, but fish also consumed a greater variety of other prey. Small tuna seemed to target small pelagic crustaceans and teleosts, and medium and large tuna to consume larger pelagic and demersal teleosts. Prey consumption increased with tuna size from 26.42 to 108.03 g d−1 for small and large tuna, respectively. Conversely, daily ration decreased with increasing tuna size from 4.10 to 1.95% body weight per day for medium and large tuna, respectively. Mackerel tuna consumed an estimated 25 036 t year−1 in the study region (170 990 km2). Diet studies are becoming increasingly important in informing ecosystem models, and this study confirmed the need for sampling regimes to capture temporal and size-related variation in diet composition, to maximize the utility of data for use in such models.
Modelling and simulations of the migration of pelagic fish
Authors: Barbaro Alethea , Einarsson Baldvin , Birnir Björn , Sigurðsson Sven , Valdimarsson Héðinn , Pálsson Ólafur Karvel , Sveinbjörnsson Sveinn , Sigurðsson Þorsteinn 
Published: April 2009

Abstract
Barbaro, A., Einarsson, B., Birnir, B., Sigurðsson, S., Valdimarsson, H., Pálsson, Ó. K., Sveinbjörnsson, S., and Sigurðsson, Þ. 2009. Modelling and simulations of the migration of pelagic fish. – ICES Journal of Marine Science, 66: 826–838. We applied an interacting particle model to the Icelandic capelin stock to reproduce the spawning migration route for three different years, successfully predicting the route for 2008. Using available temperature data and approximated currents, and without using artificial forcing terms or a homing instinct, our model was able to reproduce the observed migration routes from all 3 years. By a sensitivity analysis, we identified oceanic temperature and the balance between the influence of interaction among particles and the particles' response to temperature as the control parameters most significant in determining the migration route. One significant contribution of this paper is the inclusion of orders of magnitude more particles than similar models, which affects the global behaviour of the model by propagating information about surrounding temperature through the school more efficiently. To maintain the same dynamics between different simulations, we argue a linear relationship between the time-step, radii of interactions, and the spatial resolution, and we argue that these scale as N−1/2, where N is the number of particles.
The population genetic effects of ancestry and admixture in a subdivided cattle breed
Authors: Bray T. C. , Chikhi L. , Sheppy A. J. , Bruford M. W. 
Published: April 2009

SummaryThe genetic structure of the Dexter, a minority cattle breed with complex demographic history, was investigated using microsatellite markers and a range of statistical approaches designed to detect both admixture and genetic drift. Modern representatives of two putative ancestral populations, the Devon and Kerry, together with the different populations of the Dexter, which have experienced different demographic histories, were analysed. Breed units showed comparatively high levels of genetic variability (HE = 0.63–0.68); however, distinct genetic subgroups were detected within the Dexter, which could be attributed to known demographic events. Much lower diversity was identified in three small, isolated Dexter populations (HE = 0.52–0.55) and higher differentiation (FST > 0.13) was found. For one of these populations, where strong selection has taken place, we also found evidence of a demographic bottleneck. Three methods for quantifying breed admixture were applied and substantial method‐based variation in estimates for the genetic contribution of the two proposed ancestral populations for each subdivision of the Dexter was found. Results were consistent only in the case of a group consisting of selected Traditional Dexter animals, where the ancestor of the modern Kerry breed was also determined as the greater parental contributor to the Dexter. The inconsistency of estimation of admixture proportions between the methods highlights the potentially confounding role of genetic drift in shaping small population structure, and the consequences of accurately describing population histories from contemporary genetic data.
Detailed characterization of the porcine MC4R gene in relation to fatness and growth
Authors: Fan B. , Onteru S. K. , Plastow G. S. , Rothschild M. F. 
Published: April 2009

SummaryIn contrast to the human MC4R gene, where multiple variants have been described, several of which are associated with appetite and obesity, few MC4R variants have been reported in the pig. The most interesting polymorphism reported to date in the pig is p.Asp298Asn, which is significantly associated with variation in growth and fatness traits in most breeds and crosses. However, some reports have seemingly failed to confirm this association. The discrepancy of p.Asp298Asn associations in some pig populations suggested that further discovery of SNPs in MC4R would be useful. Utilizing the recently released pig genome sequence information, we obtained the whole MC4R genome sequence and detected five additional SNPs, a variable (CA)n repeat and a C indel in the ISU Berkshire × Yorkshire pig resource family. Linkage disequilibrium (LD) analysis revealed that the additional five SNPs were not in strong LD with p.Asp298Asn, but single marker association analysis indicated that they were significantly (P < 0.05) associated with fatness measures and very highly significantly (P < 0.0001) associated with average daily gain on test (ADGTEST). Three major haplotypes were identified and the subsequent association analyses suggested that the two non‐synonymous SNPs had different effects, e.g. p.Arg236His influenced back fat and growth on test while p.Asp298Asn was primarily associated with variation in growth rate in this population. An interaction effect between these two SNPs was found for ADGTEST, which may partly explain some of the previous discrepancies reported for MC4R in different pig populations. Examination of the p.Arg236His polymorphism in populations where the effect of p.Asp298Asn is limited is warranted.
PRNP haplotype distribution in Moroccan goats
Authors: Serrano C. , Hammouchi M. , Benomar A. , Lyahyai J. , Ranera B. , Acín C. , El Hamidi M. , Monzón M. , Badiola J. J. , Tligui N. , Zaragoza P. , Martín‐Burriel I. 
Published: April 2009

SummarySusceptibility/resistance to scrapie in sheep and goats is influenced by host prion protein gene (PRNP) genotype. In this study, we report the analysis of prion protein gene polymorphisms in 137 goats of two Moroccan populations: D’man and Chaouni. We found seven previously described amino acid polymorphisms at codons 37, 127, 137, 142, 154, 222 and 240, as well as three known silent mutations. In addition, we identified three new allelic variants: 101R and 139S in D’man goats and 145D in D’man and Chaouni individuals. The high frequency of the resistant allele 154H could offer genetic protection against the disease to the analysed animals. A total of 12 haplotypes and 28 genotypes were found, the distribution of which shows significant differences between both groups. Moreover, haplotype frequencies were compared with bibliographic data showing that the haplotype distribution of PRNP in Moroccan populations is genetically similar to Southern Italian and Greek goats.