bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantifying the performance of conventional DFT methods on a class of difficult problems: The interaction (hyper)polarizability of two water molecules as a test case
Authors: Maroulis George
Published: July 2011

We have investigated the predictive capability of a widely used group of density functional theory (DFT) methods on the interaction (hyper)polarizability of the two water molecules in the water dimer. We find that compared with conventional ab initio methods, DFT gives a different picture of the dipole moment and (hyper) polarizability for the water monomer and dimer. In addition, the DFT methods tested in this work predict for the water dimer a systematically higher value of the differential interaction‐induced second hyperpolarizability per water molecule, DHPM = [
$ \bar{\gamma} $(H2O)2]/2 −
$ \bar \gamma $
(H2O) than the ab initio ones. The interaction‐induced mean polarizability and second hyperpolarizability is predicted to be small and positive for all DFT methods used here. The respective quantities predicted by conventional post‐Hartree–Fock ab initio methods are also quite small but negative. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Metabolism of cyadox by the intestinal mucosa microsomes and gut flora of swine, and identification of metabolites by high‐performance liquid chromatography combined with ion trap/time‐of‐flight mass spectrometry
Authors: Xu Ning , Huang Lingli , Liu Zhenli , Pan Yuanhu , Wang Xu , Tao Yanfei , Chen Dongmei , Wang Yulian , Peng Dapeng , Yuan Zong hui
Published: July 2011

Cyadox (CYX), 2‐formylquinoxaline‐1,4‐dioxide cyanoacetylhydrazone, is an antimicrobial and growth‐promoting feed additive for food‐producing animals. To reveal biotransformation of CYX in swine intestine, CYX was incubated with swine intestinal microsomes and mucosa in the presence of an NADPH‐generating system and swine ileal flora and colonic flora, respectively. The metabolites of CYX were identified using high‐performance liquid chromatography combined with ion trap/time‐of‐flight mass spectrometry (LC/MS‐ITTOF). Structural elucidation of the metabolites was precisely performed by comparing their changes in molecular mass, full scan MS/MS spectra and accurate mass measurements with those of the parent drug. Finally, seven metabolites were identified as follows: three reduced metabolites (cyadox 1‐monoxide (Cy1), cyadox 4‐monoxide (Cy2) and bisdesoxycyadox (Cy4)); hydroxylation metabolite (3‐hydroxylcyadox 1‐monoxide (Cy3)); hydrolysis metabolite of the amide bond (N‐decyanoacetyl cyadox (Cy5)); a hydrogenation metabolite (11,12‐dihydro‐bisdesoxycyadox (Cy6)) and a side‐chain cleavage metabolite (2‐hydromethylquinoxaline (Cy7)). Only one metabolite (Cy1) was found in intestinal microsomes. Cy1, Cy2 and Cy4 were detected in intestinal mucosa, ileal and colonic flora. In addition, Cy3 and Cy5 were only obtained from ileal flora, and Cy6 and Cy7 alone were observed in colonic bacteria. The results indicated that N → O group reduction was the main metabolic pathway of CYX metabolism in swine ileal flora, intestinal microsomes and mucosa. New metabolic profiles of hydrogenation and cleavage on the side chain were found in colonic bacteria. Among the identified metabolites, two new metabolites (Cy6, Cy7) were detected for the first time. These studies will contribute to clarify comprehensively the metabolism of CYX in animals, and provide evidence to explain the pharmacology and toxicology effects of CYX in animals. Copyright © 2011 John Wiley & Sons, Ltd.
Ionization energies of K2X (X = F, Cl, Br, I) clusters
Authors: Veličković S. R. , Veljković F. M. , Perić‐Grujić A. A. , Radak B. B. , Veljković M. V.
Published: July 2011

The electronic structure and properties of dipotassiummonohalides are important for understanding the unique physical and chemical behavior of MnX systems. In the present study, K2X (here X = F, Cl, Br, I) clusters were generated in the vapor over salts of the corresponding potassium halide, using a magnetic sector thermal ionization mass spectrometer. The ionization energies obtained for K2F, K2Cl, K2Br, and K2I molecules were 3.82 ± 0.1 eV, 3.68 ± 0.1 eV, 3.95 ± 0.1 eV, and 3.92 ± 0.1, respectively. These experimental values of ionization energies for K2X (X = F, Br, and I) are presented for the first time. The ionization energy of K2Cl determined by thermal ionization corresponds to previous results obtained by photoionization mass spectrometry, and it agrees with the theoretical ionization energy calculated by the ab initio method. The presently obtained results support previous theoretical predictions that the excess electron in dipotassiummonohalide clusters is delocalized over two potassium atoms, which is characteristic for F‐center clusters. Copyright © 2011 John Wiley & Sons, Ltd.
EXISTING AND FUTURE CHALLENGES: THE CONCEPT OF SUCCESSFUL FISH PASSAGE IN SOUTH AMERICA
Authors: Pompeu P. S. , Agostinho A. A. , Pelicice F. M.
Published: July 2011

Most of the large rivers of South America are impounded mainly for hydropower production. The construction of fish passes has been one of the strategies adopted by Brazilian authorities and the energy sector to diminish the effects of these barriers on migratory fish communities. Despite the high investments and efforts involved, most facilities have been considered ineffective for conservation purposes. Decades of poor monitoring and the lack of specific studies have limited our knowledge on the real role of fish passes. Efficiency has been frequently defined as the proportion of fish that ascend a fish passage facility, compared to the shoal size that reaches the dam. Inspired by the notion that fishes accumulated below the dam need to migrate upstream, the quantity of fish passed upstream historically indicated successful management, as generally inferred by the fish abundance inside the fish pass. We propose a new concept for estimating fish pass efficiency for South American rivers, based on the capability of the fish pass to maintain viable populations. This broader approach is necessary because knowledge of fish habitats below and above the pass, plus the feasibility of downstream movements of eggs, larvae and adults through the reservoir and past the dam, is needed for assessing whether a fish pass is working as a conservation tool. Copyright © 2011 John Wiley & Sons, Ltd.
Deformation and Failure of Open‐Cell Foams Made of TRIP‐Steel‐ZrO2‐Composite Materials: Experimental Observations Versus Numerical Simulations
Authors: Sieber T. , Mühlich U. , Liedke T. , Ballaschk U. , Berek H. , Aneziris C. G. , Ehinger D. , Wolf S. , Krüger L.
Published: July 2011

The aim of the study is to clarify how far it is possible to describe the mechanical behavior of novel TRIP‐Steel/Mg‐PSZ composite open‐cell foam structures using beam networks generated from random tessellations. Conventional compression tests were performed with various foam samples. Furthermore, the deformation of open‐cell composite foams was observed as well by X‐ray computed tomography (XCT). Up to a compressive strain of 20% different stages of deformation could be observed. Respective bulk samples were manufactured by powder metallurgy and tested in order to determine the mechanical properties of the bulk material. Numerical simulations were employed based on the suitable modeling of foams exposed to mechanical loading. The predictions of the simulation are compared with the results of the deformation experiments.
Reinforcing Mechanism of Mg‐PSZ Particles in Highly‐Alloyed TRIP Steel
Authors: Martin S. , Richter S. , Decker S. , Martin U. , Krüger L. , Rafaja D.
Published: July 2011

Dense TRIP‐matrix composites containing 5 vol.% Mg‐PSZ as reinforcing phase were produced by employing the spark plasma sintering technique. A continuous and seamless interface between the ceramic particles and the steel matrix was achieved. Compression tests revealed better mechanical properties of the 5 vol.% Mg‐PSZ‐TRIP steel composites in comparison with both, pure and Al2O3 reinforced TRIP steel. The underlying deformation mechanism within the austenitic matrix entailed a pronounced martensite formation. An additional phase transformation was observed within the ZrO2 particles. The enhanced mechanical properties of the 5 vol.% Mg‐PSZ composite are dedicated to the transformation strengthening of the ceramic particles. Finally a model of the reinforcing mechanism is proposed.
Use of starch granules melting to control the properties of bio‐flour filled polypropylene and poly(butylene succinate) composites: Physico‐chemical properties
Authors: Tran Thierry , Lee Byoung‐Ho , Yang Han‐Seung , Chotineeranat Sunee , Sriroth Klanarong , Kim Hyun‐Joong
Published: July 2011

Bio‐composites made from polypropylene (PP) and poly(butylene succinate) (PBS) compounded with pineapple skin (P) bio‐flour, non‐destarched (CS), and destarched (C) cassava root bio‐flours were prepared by twin‐screw extrusion. In CS composites, different degrees of starch granules melting were achieved by adjusting extrusion temperature, thus enabling control of the morphological and mechanical properties. FTIR analysis indicated the formation of ester bonds between bio‐flours and compatibilizers during extrusion, which confirmed the effectiveness of these compatibilizers for improving interfacial interactions between PP and bio‐flours. Thermogravimetric analysis showed that the composites had reduced thermal stability compared to pure PBS and PP materials, due to the lower degradation temperature of the bio‐flours (261–351°C). DSC data indicated that bio‐flours improved nucleation and crystallinity, whereas, compatibilizers reduced molecular mobility and hence propagation and crystallinity.
Isolation and optimisation of the oleaginous yeast Sporobolomyces roseus for biosynthesis of 13C isotopically labelled 18-carbon unsaturated fatty acids and trans 18:1 and 18:2 derivatives through synthesis
Authors: Cui Yi , Fraser Catharine , Gardner Graeme , Huang Ching-jang , Reith Michael , Windust Anthony J
Published: July 2011

An oleaginous and psychrotrophic strain (F38-3) of Sporobolomyces roseus Kluyver & van Niel was isolated from a salt marsh environment in Nova Scotia, Canada following a screening program to select for high producers of 18-carbon unsaturated fatty acids. Fatty acid production was characterised as a function of temperature at 20 g glucose L−1, and optimal yields were obtained at 14°C, achieving 5.7 g dw biomass and 39.2% total fatty acids by dry weight, with 18:1, 18:2 and 18:3 all-cis fatty acids accounting for 49.4%, 14.3% and 6.7% of total fatty acids (TFA), respectively—the highest reported for this species. Production of 18:3 was inversely correlated to growth temperature, rising from 2% of TFA at 30°C to 8.9% at 6°C. Cultivation of isolate F38-3 on universally 13C (U-13C) labelled glucose and subsequent transesterification and isolation of the fatty acid methyl esters (FAMEs) by preparative chromatography yielded pure, highly 13C-enriched (>90%) 18:1, 18:2 and 18:3 all-cis FAMEs. The U-13C 18:1 FAME was catalytically converted to U-13C 18:1 trans-9 and purified to >99.5% purity. The U-13C 18:2 was converted by alkaline isomerisation into a 50/50 mixture of 18:2 cis-9, trans-11 and 18:2 trans-10, cis-12 isomers and purified to >95.0% purity. Overall, 10%, by weight, of labelled glucose fed to isolate F38-3 was recovered as fatty acid methyl esters and 7.5% as 18-carbon unsaturated fats, and the final isomerisation reactions resulted in yields of 80% or greater. The ultimate goal of the work is to develop methodologies to produce 13C-labelled metabolic tracers as tools to study the metabolism of trans fats.
Synthesis of Phosphatidylcholine Through Phosphatidylethanolamine N‐Methylation in Tissues of the Mussel Mytilus galloprovincialis
Authors: Athamena Ahmed , Trajkovic‐Bodennec Selena , Brichon Gérard , Zwingelstein Georges , Bodennec Jacques
Published: July 2011

We previously demonstrated the importance of upregulation of phosphatidylethanolamine N‐methylation pathway in euryhaline fish and crustaceans facing hyperosmotic conditions. In marine molluscs phosphatidylcholine synthesis through N‐methylation of phosphatidylethanolamine has not been described until now. In vivo labeling of the mussel Mytilus galloprovincialis with [1‐3H]‐ethanolamine showed that the digestive gland is the tissue expressing the highest incorporation into lipids. A sustained increase in lipid labeling was observed up to 72 h following label injection with 79–92% of radioactivity concentrated into phosphatidylethanolamine and phosphatidylcholine. A direct correlation (r = 0.47, p < 0.01) between the specific radioactivities of phosphatidylcholine in plasma and the digestive gland was observed. Moreover, the phosphatidylcholine fatty acid compositions of plasma and the digestive gland were similar but differed from those of phosphatidylcholine purified from other tissues. In vitro incubation of tissues with [1‐3H]‐ethanolamine or L‐[3‐3H]‐serine showed that a significant labeling of the choline moiety of phosphatidylcholine was observed in the digestive gland and hemocytes. Pulse‐chase experiments with [1‐3H]‐ethanolamine also demonstrated that hemocytes are exchanging the newly formed phospholipids with plasma. Finally, phosphatidylethanolamine N‐methyltransferase assays demonstrated salinity‐dependent activities in the digestive gland and hemocytes. We conclude that in M. galloprovincialis an active phosphatidylcholine synthesis through N‐methylation of phosphatidylethanolamine occurs in the digestive gland and hemocytes and that this newly formed phosphatidylcholine is partly exchanged with plasma.
Plunging cavities
Authors: CLANET C.
Published: July 2011

When a wave breaks, the tip forms a liquid sheet which impinges the base and creates an air cavity which breaks into bubbles. Gomez-Ledesma, Kiger & Duncan (J. Fluid Mech., this issue, vol. 680, 2011, pp. 5–30) have conducted a nice experiment on this problem, enabling them to discuss both the inclination of the jet and the effect of its translation. This work has interesting links with other transient cavities.
Rumen protozoa and methanogenesis: not a simple cause–effect relationship
Authors: Morgavi Diego P. , Martin Cécile , Jouany Jean-Pierre , Ranilla Maria José
Published: July 2011

Understanding the interactions between hydrogen producers and consumers in the rumen ecosystem is important for ruminant production and methane mitigation. The present study explored the relationships between rumen protozoa, methanogens and fermentation characteristics. A total of six donor sheep harbouring (F, faunated) or not (D, defaunated) protozoa in their rumens (D animals were kept without protozoa for a period of a few months (D − ) or for more than 2 years (D+)) were used inin vitroandin vivoexperiments.In vitrothe absence of protozoa decreased NH3and butyrate production and had no effect on methane. In contrast, the liquid-associated bacterial and methanogens fraction of D+ inocula produced more methane than D −  and F inoculum (P < 0·05).In vivofermentation parameters of donor animals showed the same trend on NH3and butyrate and showed that D+ animals were high methane emitters, while D −  were the lowest ( − 35 %). The concentration of dissolved dihydrogen measured after feeding followed the opposite trend. Methane emissions did not correlate with the relative abundance of methanogens in the rumen measured by quantitative PCR, but there was a trend for higher methanogens concentration in the solid-associated population of D+ animals compared with D −  animals. In contrast, PCR-denaturing gradient gel electrophoresis profiles of methanogens' methyl coenzyme-M reductase A gene showed a clear clustering in liquid-associated fractions for all three groups of donors but fewer differences in solid-associated fractions. These results show that the absence of protozoa may affect differently the methanogen community and methane emissions in wethers.
Maternal seafood consumption and infant birth weight, length and head circumference in the Norwegian Mother and Child Cohort Study
Authors: Brantsæter Anne Lise , Birgisdottir Bryndis Eva , Meltzer Helle Margrete , Kvalem Helen Engelstad , Alexander Jan , Magnus Per , Haugen Margareta
Published: July 2011

Results from previous studies on associations between maternal fish and seafood intakes and fetal growth are inconclusive. The aim of the present study was to investigate how maternal intakes of seafood, subtypes of seafood and supplementary n-3 fatty acids were associated with infant birth weight, length and head circumference in a prospective study in Norway. The study population included 62 099 participants in the Norwegian Mother and Child Cohort Study. The mothers answered an FFQ in mid pregnancy. The FFQ comprised detailed questions about intake of various seafood items and n-3 supplements. Data on infant birth weight, length and head circumference were obtained from the Medical Birth Registry. We used multivariable regression to examine how total seafood, various seafood subtypes and supplementary n-3 intakes were associated with birth size measures. Total seafood intake was positively associated with birth weight and head circumference. Lean fish was positively associated with all birth size measures; shellfish was positively associated with birth weight, while fatty fish was not associated with any birth size measures. Intake of supplementary n-3 was negatively associated with head circumference. The relative risk of giving birth to a small baby ( < 2500 g) in full-term pregnancies was significantly lower in women who consumed >60 g/d of seafood than in women who consumed ≤ 5 g/d (OR = 0·56 (95 % CI 0·35, 0·88). In conclusion, maternal seafood consumption was positively associated with birth size, driven by lean fish intake, while supplementary n-3 intake was negatively associated with infant head circumference.
Conjugated linoleic acid induces hepatic expression of fibroblast growth factor 21 through PPAR-α
Authors: Yu Jie , Yu Bing , Jiang Honglin , Chen Daiwen
Published: July 2011

Fibroblast growth factor 21 (FGF21) is a PPAR-α-regulated metabolic regulator that plays critical roles in glucose homoeostasis, lipid metabolism, insulin sensitivity and obesity. Conjugated linoleic acids (CLA), especiallytrans-10 (t-10),cis-12 (c-12), have shown anti-obesity properties. In addition, CLA is reported as a high-affinity ligand and activator of PPAR-α. This raises the possibility that FGF21 might be involved in the anti-obesity effect of CLA. In the present study, we tested the hypothesis that FGF21 expression in the liver could be induced byt-10,c-12-CLA through PPAR-α. HepG2 cells were treated with 100 μm-bovine serum albumin, 10 μm-t-10,c-12-CLA or 100 μm-t-10,c-12-CLA for 8 h. A total of ten adult C57BL/6J mice were fed with the diets containing 1 % soya oil ort-10,c-12-CLA for 5 d.t-10,c-12-CLA stimulated hepatic FGF21 mRNA abundance as determined by real-time RT-PCR.t-10,c-12-CLA also increased serum FGF21 concentrations as measured by an ELISA. Co-transfection analysis indicated that reporter gene expression from the mouse FGF21 promoter was induced byt-10,c-12-CLA in a PPAR-α-dependent manner. Taken together, these results suggest thatt-10,c-12-CLA induces hepatic FGF21 expression through PPAR-α. This FGF21 and PPAR-α linkage may provide another potential explanation for the anti-obesity effect oft-10,c-12-CLA.
Retinal risks of high-dose ornithine supplements: a review
Authors: Hayasaka Seiji , Kodama Tatsuo , Ohira Akihiro
Published: July 2011

We reviewed the literature on ornithine supplementation and related topics. Nutritionists and physicians have reported that ornithine supplementation is useful. Paediatricians and biochemists have reported that ornithine is supplemented for NH3detoxification in the hyperornithinaemia–hyperammonaemia–homocitrullinuria (HHH) syndrome. In contrast, ophthalmic researchers have reported retinotoxicity associated with high-dose ornithine.In vivoandin vitroexperiments have shown that high concentrations of ornithine or its metabolites are toxic to the retinal pigment epithelial (RPE) cells. Long-term (exceeding a few years) and high concentrations (exceeding 600 μmol/l) of ornithine in the blood induce retinal toxicity in gyrate atrophy of the choroid and retina (GA). Intermittent high levels of ornithine do not lead to retinal lesions. Constant blood ornithine levels between 250 and 600 μmol/l do not induce retinal lesions or cause a very slowly progressive retinal degeneration. Blood ornithine levels below 250 μmol/l do not produce retinal alteration. We concluded that short-term, low-dose or transient high-dose ornithine intake is safe for the retina; its nutritional usefulness and effect on NH3detoxification are supported by many researchers, but the effect may be limited; and long-term, high-dose ornithine intake may be risky for the retina. Patients with GA should avoid taking ornithine; amino acid supplementation should be administered carefully for patients with the HHH syndrome, relatives of patients with GA (heterozygotes) and subjects with RPE lesions; and blood ornithine levels and retinal conditions should be evaluated in individuals taking long-term, high-dose ornithine.
How to deal with genotype uncertainty in variance component quantitative trait loci analyses
Authors: SHEN XIA , RÖNNEGÅRD LARS , CARLBORG ÖRJAN
Published: July 2011

Dealing with genotype uncertainty is an ongoing issue in genetic analyses of complex traits. Here we consider genotype uncertainty in quantitative trait loci (QTL) analyses for large crosses in variance component models, where the genetic information is included in identity-by-descent (IBD) matrices. An IBD matrix is one realization from a distribution of potential IBD matrices given available marker information. In QTL analyses, its expectation is normally used resulting in potentially reduced accuracy and loss of power. Previously, IBD distributions have been included in models for small human full-sib families. We develop an Expectation–Maximization (EM) algorithm for estimating a full model based on Monte Carlo imputation for applications in large animal pedigrees. Our simulations show that the bias of variance component estimates using traditional expected IBD matrix can be adjusted by accounting for the distribution and that the calculations are computationally feasible for large pedigrees.
Genetic analysis of complex traits via Bayesian variable selection: the utility of a mixture of uniform priors
Authors: KNÜRR TIMO , LÄÄRÄ ESA , SILLANPÄÄ MIKKO J.
Published: July 2011

A new estimation-based Bayesian variable selection approach is presented for genetic analysis of complex traits based on linear or logistic regression. By assigning a mixture of uniform priors (MU) to genetic effects, the approach provides an intuitive way of specifying hyperparameters controlling the selection of multiple influential loci. It aims at avoiding the difficulty of interpreting assumptions made in the specifications of priors. The method is compared in two real datasets with two other approaches, stochastic search variable selection (SSVS) and a re-formulation of Bayes B utilizing indicator variables and adaptive Student'st-distributions (IAt). The Markov Chain Monte Carlo (MCMC) sampling performance of the three methods is evaluated using the publicly available software OpenBUGS (model scripts are provided in the Supplementary material). The sensitivity of MU to the specification of hyperparameters is assessed in one of the data examples.
Uniculm and conventional tillering barley accessions under northern growing conditions
Authors: MÄKELÄ P. , MUURINEN S.
Published: July 2011

At high northern latitudes, growing seasons are short with long days. In these conditions, tillering is an unwanted trait in barley (Hordeum vulgare L.), because the grains on tillers develop later than those on the main stem and are often harvested before they are fully mature, leading to reductions in overall quality. Hence, the uniculm growth habit has been considered an interesting option for boreal barley production. The aim of the present study was to determine the differences in the yield formation of conventional tillering and uniculm barley, using two pairs of near-isogenic lines and two controls. Uniculm and conventional tillering barley were grown in three experiments conducted at Suitia Experimental Farm, University Helsinki, Finland during 1999–2001. Samples were collected frequently to monitor the biomass and leaf area accumulation. Water-soluble carbohydrate content was analysed at anthesis and at maturity in different plant parts. At maturity, the numbers of spikes/plant and grains/spike were calculated and grain yield weighed. The grain yield of the uniculm barleys was stable over these growing seasons, but it was only half that of the conventional barley cultivars due to the absence of spike-bearing tillers, lower spike grain number and spike weight. In addition, the ability to transport photosynthesized carbohydrates to grains may have been reduced. Thus, it seems that uniculm barleys do not provide further improvement in barley yield.
Bronchogenic cysts as a cause of infantile stridor: case report and literature review
Authors: Goswamy J , de Kruijf S , Humphrey G , Rothera M P , Bruce I A
Published: July 2011

Introduction:

Cystic lesions related to the upper airway are an unusual cause of infantile stridor. Such a lesion may exert a mass effect, with subsequent airway compromise.

Case report:

A six-month-old boy was transferred to our unit with a right-sided, level IV neck lump and a three-month history of chronic cough and, latterly, inspiratory stridor. Computed tomography revealed a large, unilocular, cystic, cervicothoracic lesion causing marked compression of the trachea. Airway endoscopy subsequently revealed the larynx to be displaced to the left, with severe external compression of the trachea from just below the subglottic level to immediately above the carina. The mediastinal lesion was excised via an external approach. The histological diagnosis was a bronchogenic cyst.

Conclusion:

Bronchogenic cysts are a rare cause of infantile stridor, and should be considered in the differential diagnosis of cystic cervical and mediastinal masses. Surgical excision is the treatment of choice.
The effect of host age on feeding performance of fleas
Authors: LIBERMAN VICTORIA , KHOKHLOVA IRINA S. , DEGEN A. ALLAN , KRASNOV BORIS R.
Published: July 2011

We asked whether the age of a rodent host affects the feeding performance of fleas. We predicted that fleas would perform better on young and old than on adult rodents. To test this prediction, we determined bloodmeal size, rate of digestion and time of survival after a single bloodmeal inXenopsylla ramesisfeeding onMeriones crassusof different ages. Fleas took less blood from subadult and adult than from juvenile and old animals. Fleas digested blood of old hosts at the highest rate and blood of juvenile hosts most slowly. After a bloodmeal, fleas survived the longest if fed on a juvenile host. The effect of host gender on bloodmeal size and survival after a bloodmeal was manifested only in (a) subadult and adult hosts and (b) subadult hosts, respectively. Host gender affected the rate of digestion differently among digestion stages and host age cohorts. We explain the observed patterns in flea performance in terms of changes in the host's immune defences and nutritional quality of blood during the host's individual life. Our observations suggested that a host of a particular age could not be unequivocally predicted to be more or less beneficial for a parasite than a younger or an older host.
Head lice prevalence among households in Norway: importance of spatial variables and individual and household characteristics
Authors: RUKKE BJØRN ARNE , BIRKEMOE TONE , SOLENG ARNULF , LINDSTEDT HEIDI HEGGEN , OTTESEN PREBEN
Published: July 2011

Head lice prevalence varies greatly between and within countries, and more knowledge is needed to approach causes of this variation. In the present study, we investigated head lice prevalence among elementary school students and their households in relation to individual and household characteristics as well as spatial variables. The investigation included households from 5 geographically separated municipalities. Present infestations among household members as well as previous infestations in the household were reported in a questionnaire. In elementary school students prevalence was low (1·63%), but more than one-third of the households (36·43%) had previously experienced pediculosis. Prevalence was higher in elementary school students than in other household members, and highest in third-grade children. Prevalence was also influenced by the school attended, which suggested that interactions between children in the same school are important for head lice transmission. Previous occurrence of head lice in homes also increased the risk of present infestation. Prevalence of previous infestations was higher in households with more children and in more densely populated municipalities, indicating that the density of hosts or groups of hosts influences transmission rates. These results demonstrate that information of hosts’ spatial distribution as well as household and individual characteristics is needed to better understand head lice population dynamics.
Predicting self- and other-directed violence among discharged psychiatric patients: the roles of anger and psychopathic traits
Authors: Swogger M. T. , Walsh Z. , Homaifar B. Y. , Caine E. D. , Conner K. R.
Published: July 2011

Background

We examined the extent to which trait anger and psychopathic traits predicted post-discharge self-directed violence (SDV) and other-directed violence (ODV) among psychiatric patients.

Method

Participants were 851 psychiatric patients sampled from in-patient hospitals for the MacArthur Violence Risk Assessment Study (MVRAS). Participants were administered baseline interviews at the hospital and five follow-up interviews in the community at approximately 10-week intervals. Psychopathy and trait anger were assessed with the Psychopathy Checklist: Screening Version (PSC:SV) and the Novaco Anger Scale (NAS) respectively. SDV was assessed during follow-ups with participants and ODV was assessed during interviews with participants and collateral informants. Psychopathy facets and anger were entered in logistic regression models to predict membership in one of four groups indicating violence status during follow-up: (1) SDV, (2) ODV, (3) co-occurring violence (COV), and (4) no violence.

Results

Anger predicted membership in all three violence groups relative to a non-violent reference group. In unadjusted models, all psychopathy facets predicted ODV and COV during follow-up. In adjusted models, interpersonal and antisocial traits of psychopathy predicted membership in the ODV group whereas only antisocial traits predicted membership in the COV group.

Conclusions

Although our results provide evidence for a broad role for trait anger in predicting SDV and ODV among discharged psychiatric patients, they suggest that unique patterns of psychopathic traits differentially predict violence toward self and others. The measurement of anger and facets of psychopathy during discharge planning for psychiatric patients may provide clinicians with information regarding risk for specific types of violence.
Automorphic properties of generating functions for generalized odd rank moments and odd Durfee symbols
Authors: ALFES CLAUDIA , BRINGMANN KATHRIN , LOVEJOY JEREMY
Published: July 2011

We define two-parameter generalizations of Andrews' (k+1)-marked odd Durfee symbols and 2kth symmetrized odd rank moments, and study the automorphic properties of some of their generating functions. When k = 0 we obtain families of modular forms and mock modular forms. When k ≥ 1, we find quasimodular forms and quasimock modular forms.
On moduli spaces of Hitchin pairs
Authors: BISWAS INDRANIL , GOTHEN PETER B. , LOGARES MARINA
Published: July 2011

LetXbe a compact Riemann surfaceXof genus at–least two. Fix a holomorphic line bundleLoverX. Letbe the moduli space of Hitchin pairs (E, φ ∈H0(End0(E) ⊗L)) overXof rankrand fixed determinant of degreed. The following conditions are imposed:

(i)

deg(L) ≥ 2g−2,r≥ 2, andL⊗rKX⊗r;

(ii)

(r, d) = 1; and

(iii)

ifg= 2 thenr≥ 6, and ifg= 3 thenr≥ 4.

We prove that that the isomorphism class of the varietyuniquely determines the isomorphism class of the Riemann surfaceX. Moreover, our analysis shows thatis irreducible (this result holds without the additional hypothesis on the rank for low genus).
Augmenting Behavioural Activation Treatment with the Behavioural Activation and Inhibition Scales
Authors: Bowins Brad E.
Published: July 2011

Background: Although behavioural activation therapy is effective for depression there is always room for improvement, and also the need to extend this treatment modality to anxiety disorders. Method: A search was conducted for an easy to apply and effective method of achieving these aims. Results: To both enhance the effectiveness of behavioural activation treatment for depression and facilitate its extension to anxiety disorders, it is proposed that the Behavioral Approach/Activation System (BAS) and Behavioral Inhibition System (BIS) be incorporated. BIS/BAS Scales are easy to administer and evaluate ensuring that there is minimal added complexity. Overall, BAS, BAS subscale (Drive, Reward Responsiveness, and Fun Seeking) and BIS scores provide valuable information pertaining to a person's approach and avoidance responses. This general information, plus that derived from specific scale items, can be used to guide more focused and effective behavioural activation strategies. Brief case examples are provided to demonstrate how the BIS/BAS Scales can be applied. Conclusion: BIS/BAS Scales offer an easy to apply and effective means of enhancing behavioural activation therapy for depression and extending this treatment modality to anxiety disorders.
Carbon system changes in the East China Sea induced by Typhoons Tina and Winnie in 1997
Authors: Wada Akiyoshi , Midorikawa Takashi , Ishii Masao , Motoi Tatsuo
Published: July 2011

A simple chemical scheme was introduced into the Meteorological Research Institute Community Ocean Model (MRI.COM) for investigating the rapid CO2 flux increase at a moored buoy in the East China Sea caused by the passages of Typhoons Tina and Winnie in 1997. MRI.COM well reproduced variations in the observed water temperature and pCO2sea at 1 m depth and in the air‐sea CO2 flux at the buoy. Even though the analyzed magnitudes of the air‐sea CO2 fluxes were of the same order, the sudden CO2 flux change occurred nearly 2 days after Tina and nearly 3 days after Winnie. The increase in pCO2sea normalized to a temperature of 29°C induced by Winnie appeared longer than that induced by Tina. The numerical simulation results showed clear differences in the oceanic response between the two typhoons. In the case of Tina, upwelling along the continental shelf played a crucial role in rapidly decreasing the water temperature and transporting seawater with low pCO2sea and high dissolved inorganic carbon (DIC) to the upper ocean. In contrast, water with relatively high pCO2sea and low DIC transported by strong horizontal advection of the Kuroshio Current was vertically mixed by the passage of Winnie, resulting in a cool, deep mixed layer at the buoy. The surface seawater hydrogen ion concentration (pH) temporarily decreased during the passages of Tina and Winnie. In the case of Tina, pH decreased by at most 0.03 and for only 1 day.
Science initiative for international development
Authors: Showstack Randy
Published: July 2011

A new initiative to use science to address global development challenges was launched by the U.S. National Science Foundation (NSF) and the U.S. Agency for International Development (USAID) on 7 July. Partnerships for Enhanced Engagement in Research (PEER) will capitalize on competitively awarded investments to support and build scientific and technical capacity in the developing world, according to the agencies. USAID has allocated $7 million for PEER, which the agencies indicate could leverage an additional $25–50 million in NSFfunded research at U.S. institutions to focus on issues including climate change, disaster mitigation, water, renewable energy, and food security. The program is beginning with six pilot programs in Asia and Africa, including fostering a Bangladeshi seismological community, studying the impacts of land use on biodiversity dynamics in Burkina Faso, and examining climate change and integrated resource management around Agougou Natural Pond in Mali.
Worsnop receives 2010 Yoram J. Kaufman Award for Unselfish Cooperation in Research: Citation
Authors: Robock Alan
Published: July 2011

Douglas R. Worsnop received the 2010 Yoram J. Kaufman Unselfish Cooperation in Research Award at the 2010 AGU Fall Meeting, held 13–17 December in San Francisco, Calif. The award recognizes “broad influence in atmospheric science through exceptional creativity, inspiration of younger scientists, mentoring, international collaborations, and unselfish cooperation in research.”
Worsnop receives 2010 Yoram J. Kaufman Award for Unselfish Cooperation in Research: Response
Authors: Worsnop Douglas R.
Published: July 2011

Douglas R. Worsnop received the 2010 Yoram J. Kaufman Unselfish Cooperation in Research Award at the 2010 AGU Fall Meeting, held 13–17 December in San Francisco, Calif. The award recognizes “broad influence in atmospheric science through exceptional creativity, inspiration of younger scientists, mentoring, international collaborations, and unselfish cooperation in research.”
Measuring properties of contrails to estimate their effects on climate
Authors: Balcerak Ernie
Published: July 2011

Condensation trails, or so‐called contrails, formed by freezing of ice crystals in the exhaust from aircraft jet engines, could affect climate. Like natural cirrus clouds, contrails change atmospheric temperatures not only by blocking sunlight from reaching the Earth's surface but also by preventing terrestrial radiation from escaping the Earth's atmosphere. However, contrails' effects on climate are not well constrained because few studies of contrail properties exist, and hence, their microphysical properties are poorly known. In a new study, Voigt et al. directly measured ice particle sizes and numbers in 14 contrails from nine different aircraft of the present‐day commercial fleet, including the largest operating passenger aircraft. They obtained an extensive data set of contrails from which they determined the contrail optical depth, a measure of how much light is attenuated by these man‐made clouds. (Geophysical Research Letters, doi:10.1029/2011GL047189, 2011)
Potential for Atlantic current collapse confirmed
Authors: Schultz Colin
Published: July 2011

Potential for Atlantic current collapse confirmed The Atlantic meridional overturning circulation (AMOC) is a gigantic heat, salt, and nutrient mixer that spans the length of the Atlantic Ocean. Drawing warming surface waters up from the south through the Gulf Stream and along the North Atlantic Current, the system has a large amount of control over the climate of western Europe. Once in the North Atlantic, the water cools, becoming more dense and sinking to between 3000 and 5000 meters in depth before commencing a return journey south. Both paleoclimate evidence and simplified ocean circulation models suggest that the AMOC may have two stable states (either its current behavior or an “off” mode), and this has left some researchers worried that the system may experience a sudden and drastic cessation. (Geophysical Research Letters, doi:10.1029/2011GL047208, 2011)
Theory and simulations of the scaling of magnetic reconnection with symmetric shear flow
Authors: Cassak P. A.
Published: July 2011

The scaling of magnetic reconnection in the presence of an oppositely directed sub-Alfvénic shear flow parallel to the reconnecting magnetic field is studied using analytical scaling arguments and two-dimensional two-fluid numerical simulations of collisionless (Hall) reconnection. Previous studies noted that the reconnection rate falls and the current sheet tilts with increasing flow speed, but no quantitative theory was presented. This study presents a physical model of the effect of shear flow on reconnection, resulting in expressions for the scaling of properties such as the reconnection rate, outflow speed, and thickness and length of the dissipation region, which are verified numerically. Differences between Hall and Sweet-Parker reconnection are pointed out. The tilting of the current sheet is explained physically and a quantitative prediction is presented and verified.
Measurement of the temperature of an ultracold ion source using time-dependent electric fields
Authors: Debernardi N. , Reijnders M. P. , Engelen W. J. , Clevis T. T. J. , Mutsaers P. H. A. , Luiten O. J. , Vredenbregt E. J. D.
Published: July 2011

We report on a measurement of the characteristic temperature of an ultracold rubidium ion source, in which a cloud of laser-cooled atoms is converted to ions by photo-ionization. Extracted ion pulses are focused on a detector with a pulsed-field technique. The resulting experimental spot sizes are compared to particle-tracking simulations, from which an effective source temperature T = (3 ± 2) mK and the corresponding transversal reduced emittance εr = 1.4 × 10−8 m rad eV are determined. Space charge effects that may affect the measurement are also discussed.
Molecular dynamics study of the effects of translational energy and incident angle on dissociation probability of hydrogen/deuterium molecules on Pt(111)
Authors: Koido Tetsuya , Tomarikawa Ko , Yonemura Shigeru , Tokumasu Takashi
Published: July 2011

The dissociation probabilities of H2 and D2 molecules on a Pt(111) surface with thermal motion were analyzed using the molecular dynamics (MD) method. The potential constructed using the embedded atom method was used as the interaction potential between a gas molecule and the surface. The effects of changing the translational energy and incident polar angle of D2 molecules impinging on a Pt(111) surface were analyzed using MD simulations. The effect of initial orientation, incident azimuthal angle, rotational energy of gas molecules, and the impinging points on the surface were averaged by setting the initial values in a random manner. When the molecules approach normal to the surface, the dissociation probability increases with the initial translational energy. At larger incident angles, the probability becomes smaller. The impinging processes were categorized in terms of reaching the chemisorption layer by analyzing the repulsion forces from the surface. The effective translational energies for impingement, both normal and parallel to the surface, play important but different roles in terms of molecules reaching the chemisorption layer and the dissociation probability. The results were compared to those obtained by molecular beam experiments to check the validity of the simulations. The results indicate that the dependence of the dissociation probability on the translational energy and incident angle is in approximate agreement with that from experiments.
Thermal conductivities and conduction mechanisms of Sb-Te Alloys at high temperatures
Authors: Lan Rui , Endo Rie , Kuwahara Masashi , Kobayashi Yoshinao , Susa Masahiro
Published: July 2011

Sb-Te alloys have drawn much attention due to its application in phase change memory as well as the unique properties as chalcogenide. In this work, the thermal conductivities of Sb-x mol%Te alloys (x = 14, 25, 44, 60, 70, and 90) have been measured by the hot strip method from room temperature up to temperature just below the respective melting points. For the intermetallic compound Sb2Te3 (x = 60), the thermal conductivity decreases up to approximately 600 K and then increases. For other Sb-x mol%Te alloys where x > 60, the thermal conductivities of the alloys decrease with increasing temperature. In contrast, for x < 60, the thermal conductivities of the alloys keep roughly constant up to approximately 600 K and then increase with increasing temperature. It is proposed that free electron dominates the heat transport below 600 K, and ambipolar diffusion also contributes to the increase in the thermal conductivity at higher temperatures. The prediction equation from temperature and chemical composition has been proposed for thermal conductivities of Sb-Te alloys.
Correlation of residual impurity concentration and acceptor electron paramagnetic resonance linewidth in isotopically engineered Si
Authors: Stegner A. R. , Tezuka H. , Riemann H. , Abrosimov N. V. , Becker P. , Pohl H.-J. , Thewalt M. L. W. , Itoh K. M. , Brandt M. S.
Published: July 2011

Electron paramagnetic resonance (EPR) experiments on boron acceptors in isotopically engineered 28Si samples with different degrees of chemical and isotopic purity are reported. The strong suppression of isotope-induced broadening effects in this material allows a direct observation of the linear correlation between the width of the inter-subband Δm = 1 EPR line and the concentrations of carbon, oxygen, and boron point defects down to a total concentration of ≈2 × 1015 cm−3. When the impurity level is decreased further, the linewidth does not fall below 2.3 ± 0.2 mT, for which we discuss possible origins.
Lattice thermal conductivity of the Cu3SbSe4-Cu3SbS4 solid solution
Authors: Skoug Eric J. , Cain Jeffrey D. , Morelli Donald T. , Kirkham Melanie , Majsztrik Paul , Lara-Curzio Edgar
Published: July 2011

The compositional dependence of the crystal structure and lattice thermal conductivity in the Cu3SbSe4-Cu3SbS4 system has been studied. The lattice parameters of the Cu3SbSe4-xSx compounds decrease linearly with x, and the tetragonal structure (space group 14−2m no. 121) of the end compounds is maintained at all compositions. The lattice thermal conductivity is much lower than that predicted by a simple rule of mixtures, which is typical for a solid solution. The Debye model produces a very reasonable fit to the experimental lattice thermal conductivity data when phonon scattering due to atomic mass and size differences between Se and S is taken into account. Compounds in this series are likely to improve upon the thermoelectric performance of Cu3SbSe4, which has shown ZT = 0.72 when optimized.
Modular PbSrS/PbS mid-infrared vertical external cavity surface emitting laser on Si
Authors: Khiar A. , Rahim M. , Fill M. , Felder F. , Zogg H. , Cao D. , Kobayashi S. , Yokoyama T. , Ishida A.
Published: July 2011

A mid-infrared vertical external cavity surface emitting laser (VECSEL) based on undoped PbS is described herein. A 200 nm-thick PbS active layer embedded between PbSrS cladding layers forms a double heterostructure. The layers are grown on a lattice and thermal expansion mismatched Si-substrate. The substrate is placed onto a flat bottom Bragg mirror again grown on a Si substrate, and the VECSEL is completed with a curved top mirror. Pumping is done optically with a 1.55 μm laser diode. This leads to an extremely simple modular fabrication process. Lasing wavelengths range from 3–3.8 μm at 100–260 K heat sink temperature. The lowest threshold power is ∼210 mWp and highest output power is ∼250 mWp. The influence of the different recombination mechanism as well as free carrier absorption on the threshold power is modeled.
Domain wall induced magnetoresistance in a superconductor/ferromagnet nanowire
Authors: Miao G. X. , Mascaro M. D. , Nam C. H. , Ross C. A. , Moodera J. S.
Published: July 2011

In a nanowire consisting of a ferromagnet/insulator/superconductor multilayer structure, the superconductivity is shown to depend strongly on the configuration of the magnetic domain walls in the neighboring ferromagnetic layer, yielding a high magnetoresistance within a temperature range near the superconducting transition temperature TC. Micromagnetic simulations confirmed that out-of-plane stray magnetic fields from uncompensated magnetic poles play a dominant role in inducing magnetoresistance in this particular system.