bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low‐Temperature Preparation of β‐Si3N4 Porous Ceramics with a Small Amount of Li2O–Y2O3
Authors: Fan Lei , Zhou Meng , Wang Hongjie , Shi Zhongqi , Lu Xuefeng , Wang Chao 
Published: March 2014

Porous β‐Si3N4 ceramics are sintered at 1600°C in N2 and postheat treated at 1500°C under vacuum using Li2O and Y2O3 as the sintering additives. The partial sintering and phase transformation are promoted at low temperature by the addition of Li2O. The addition of Y2O3 is advantageous for the formation of high aspect ratio β‐Si3N4 grains. After postheat treatment, a large amount of intergranular glassy phase is removed, and the Li content in the samples is decreased. By this method, the β‐Si3N4 porous ceramic with a porosity of 54.1% and high flexural strength of 110 ± 8.1 MPa can be prepared with a small amount of sintering additives, 0.66 wt% Li2O and 0.33 wt% Y2O3, and it is suitable for high‐temperature applications.
Preparation of Transparent 3Y‐TZP Nanoceramics with No Low‐Temperature Degradation
Authors: Xiong Yan , Fu Zhengyi , Pouchly Vaclav , Maca Karel , Shen Zhijian 
Published: March 2014

The progresses of the relative density, average grain size (GS), and maximum pore size entering into the final sintering stage are investigated in 3 mol% yttria‐stabilized tetragonal zirconia polycrystals (3Y‐TZP) compacts in the range of 87%~99% theoretical density. It is found that during conventional pressureless sintering, the pores in the compact enlarged dramatically, which appears to be the major obstacle for preparing fully dense nanoceramics. Transparent 3Y‐TZP nanoceramics with an average GS of 87 nm were prepared by exploiting microstructural refinement on nanoscale. The yields a maximal optical transmittance of 67% and shows no noticeable low‐temperature degradation after 100 h aging at 134°C under a hydrothermal pressure of two bars.
Relative immaturity and ADHD: findings from nationwide registers, parent‐ and self‐reports
Authors: Halldner Linda , Tillander Annika , Lundholm Cecilia , Boman Marcus , Långström Niklas , Larsson Henrik , Lichtenstein Paul 
Published: March 2014

BackgroundWe addressed if immaturity relative to peers reflected in birth month increases the likelihood of ADHD diagnosis and treatment.MethodsWe linked nationwide Patient and Prescribed Drug Registers and used prospective cohort and nested case–control designs to study 6–69 year‐old individuals in Sweden from July 2005 to December 2009 (Cohort 1). Cohort 1 included 56,263 individuals diagnosed with ADHD or ever used prescribed ADHD‐specific medication. Complementary population‐representative cohorts provided DSM‐IV ADHD symptom ratings; parent‐reported for 10,760 9‐year‐old twins born 1995–2000 from the CATSS study (Cohort 2) and self‐reported for 6,970 adult twins age 20–47 years born 1959–1970 from the STAGE study (Cohort 3). We calculated odds ratios (OR:s) for ADHD across age for individuals born in November/December compared to January/February (Cohort 1). ADHD symptoms in Cohorts 2 and 3 were studied as a function of calendar birth month.ResultsADHD diagnoses and medication treatment were both significantly more common in individuals born in November/December versus January/February; peaking at ages 6 (OR: 1.8; 95% CI: 1.5–2.2) and 7 years (OR: 1.6; 95% CI: 1.3–1.8) in the Patient and Prescribed Drug Registers, respectively. We found no corresponding differences in parent‐ or self‐reported ADHD symptoms by calendar birth month.ConclusionRelative immaturity compared to class mates might contribute to ADHD diagnosis and pharmacotherapy despite absence of parallel findings in reported ADHD symptom loads by relative immaturity. Increased clinical awareness of this phenomenon may be warranted to decrease risk for imprecise diagnostics and treatment. We speculate that flexibility regarding age at school start according to individual maturity could reduce developmentally inappropriate demands on children and improve the precision of ADHD diagnostic practice and pharmacological treatment.
Effect of music on pain, anxiety, and patient satisfaction in patients who present to the emergency department in Turkey
Authors: Parlar Kilic Serap , Karadag Gulendam , Oyucu Serpil , Kale Ozlem , Zengin Suat , Ozdemir Emine , Korhan Esra Akin 
Published: March 2014

AbstractAimThe objective of this study is to evaluate the effect of music therapy on pain, anxiety, and patient satisfaction in patients who present to the emergency department in Turkey.MethodsThis controlled and experimental study was conducted in the emergency department of a hospital in Turkey between July and October 2012. The study sample consisted of 200 patients in total, 100 forming the intervention group and 100 being the control group, who fell under color code green in the triage system and came with complaints of pain due to nausea/vomiting and diarrhea, abdominal pain, headaches, and joint pain. A questionnaire, the State Anxiety Scale, and the Visual Analog Scale to measure the patients' level of pain were used in the study. The questionnaires of the intervention group were administered after playing the music.ResultsWhen the intervention and control groups were compared, it was observed that there was a significant decrease in the VASP and STAI‐S scores in favor of the intervention group. It was observed that 21.0% of the patients in the intervention group were very pleased to hear music in the emergency department, 58% of them were moderately or at least a little pleased, and 21.0% were not pleased at all.ConclusionThe results showed that music therapy had a positive effect in terms of reducing the severity of pain and the level of anxiety in patients, that only a very small portion of the patients were not pleased to listen to music in the emergency department.
HPC‐1/syntaxin 1A and syntaxin 1B play distinct roles in neuronal survival
Authors: Kofuji Takefumi , Fujiwara Tomonori , Sanada Masumi , Mishima Tatsuya , Akagawa Kimio 
Published: March 2014

AbstractTwo types of syntaxin 1 isoforms, HPC‐1/syntaxin 1A (STX1A) and syntaxin 1B (STX1B), are thought to have similar functions in exocytosis of synaptic vesicles. STX1A−/− mice which we generated previously develop normally, possibly because of compensation by STX1B. We produced STX1B−/− mice using targeted gene disruption and investigated their phenotypes. STX1B−/− mice were born alive, but died before postnatal day 14, unlike STX1A−/− mice. Morphologically, brain development in STX1B−/− mice was impaired. In hippocampal neuronal culture, the cell viability of STX1B−/− neurons was lower than that of WT or STX1A−/− neurons after 9 days. Interestingly, STX1B−/− neurons survived on WT or STX1A−/− glial feeder layers as well as WT neurons. However, STX1B−/− glial feeder layers were less effective at promoting survival of STX1B−/− neurons. Conditioned medium from WT or STX1A−/− glial cells had a similar effect on survival, but that from STX1B−/− did not promote survival. Furthermore, brain‐derived neurotrophic factor (BDNF) or neurotrophin‐3 supported survival of STX1B−/− neurons. BDNF localization in STX1B−/− glial cells was disrupted, and BDNF secretion from STX1B−/− glial cells was impaired. These results suggest that STX1A and STX1B may play distinct roles in supporting neuronal survival by glia.
image
Syntaxin 1A (STX1A) and syntaxin 1B (STX1B) are thought to have similar functions as SNARE proteins. However, we found that STX1A and STX1B play distinct roles in neuronal survival using STX1A−/− mice and STX1B−/− mice. STX1B was important for neuronal survival, possibly by regulating the secretion of neurotrophic factors, such as BDNF, from glial cells.
HIV‐1 protein Tat produces biphasic changes in NMDA‐evoked increases in intracellular Ca2+ concentration via activation of Src kinase and nitric oxide signaling pathways
Authors: Krogh Kelly A. , Wydeven Nicole , Wickman Kevin , Thayer Stanley A. 
Published: March 2014

AbstractHIV‐associated neurocognitive disorders afflict about half of HIV‐infected patients. HIV‐infected cells shed viral proteins, such as the transactivator of transcription (Tat), which can cause neurotoxicity by over activation of NMDA receptors. Here, we show that Tat causes a time‐dependent, biphasic change in NMDA‐evoked increases in intracellular Ca2+ concentration ([Ca2+]i). NMDA‐evoked responses were potentiated following 2‐h exposure to Tat (50 ng/mL). Tat‐induced potentiation of NMDA‐evoked increases in [Ca2+]i peaked by 8 h and then adapted by gradually reversing to baseline by 24 h and eventually dropping below control by 48 h. Tat‐induced potentiation of NMDA‐evoked responses was blocked by inhibition of lipoprotein receptor‐related protein (LRP) or Src tyrosine kinase. Potentiation was unaffected by inhibition of nitric oxide synthase (NOS). However, NOS activity was required for adaptation. Adaptation was also prevented by inhibition of soluble guanylate cyclase (sGC) and cyclic guanosine monophosphate‐dependent protein kinase G (PKG). Together, these findings indicate that Tat potentiates NMDA‐evoked increases in [Ca2+]i via LRP‐dependent activation of Src and that this potentiation adapts via activation of the NOS/sGC/PKG pathway. Adaptation may protect neurons from excessive Ca2+ influx and could reveal targets for the treatment of HIV‐associated neurocognitive disorders.
image
HIV‐associated neurocognitive disorders (HAND) afflict about half of HIV‐infected patients. HIV‐infected cells shed viral proteins, such as the transactivator of transcription (Tat), which can cause neurotoxicity by over activation of NMDA receptors (NMDARs). We show that HIV‐1 Tat evoked biphasic changes in NMDA‐evoked [Ca2+]i responses. Initially, Tat potentiated NMDA‐evoked responses following LRP‐mediated activation of Src kinase. Subsequently, Tat‐induced NMDAR potentiation adapted by activation of a NOS/sGC/PKG pathway that attenuated NMDA‐evoked increases in [Ca2+]i. Adaptation may be a novel neuroprotective mechanism to prevent excessive Ca2+ influx. Solid and dashed arrows represent direct and potentially indirect connections, respectively.
Measuring Readability in Financial Disclosures
Authors: LOUGHRAN TIM , MCDONALD BILL 
Published: March 2014

ABSTRACTDefining and measuring readability in the context of financial disclosures becomes important with the increasing use of textual analysis and the Securities and Exchange Commission's plain English initiative. We propose defining readability as the effective communication of valuation‐relevant information. The Fog Index—the most commonly applied readability measure—is shown to be poorly specified in financial applications. Of Fog's two components, one is misspecified and the other is difficult to measure. We report that 10‐K document file size provides a simple readability proxy that outperforms the Fog Index, does not require document parsing, facilitates replication, and is correlated with alternative readability constructs.
The supervisor feedback environment is empowering, but not all the time: Feedback orientation as a critical moderator
Authors: Gabriel Allison S. , Frantz Noelle B. , Levy Paul E. , Hilliard Adam W. 
Published: March 2014

Literature on the feedback environment has purported that supportive environments fostered by supervisors lead to improvements in employee well‐being and performance. However, little research has considered how the feedback environment affects workplace motivation or identified boundary conditions of the feedback environment to outcome relationship. The current study extends the literature by utilizing a predictive design to examine how the supervisor feedback environment affects dimensions of employee psychological empowerment (meaning, competence, self‐determination, and impact) after 3 months in a sample of correctional facility employees. Further, we tested how an employee's feedback orientation, or propensity to seek and utilize feedback, attenuated or enhanced the relationship between supervisor feedback environment and empowerment. Results demonstrated that perceptions of the supervisor feedback environment differentially related to each dimension of empowerment, with the feedback environment being a positive predictor of impact and a marginally positive predictor of meaning. Moreover, when feedback orientation was high, the feedback environment exhibited a strong positive relationship with meaning, competence, and self‐determination; when feedback orientation was low, relationships actually became weaker when predicting meaning and negative when predicting competence and self‐determination. The results clarify the scope of impact of the supervisor feedback environment, offering theoretical and practical implications.Practitioner points

The feedback environment fostered by supervisors can increase employee empowerment.

An employee's feedback orientation is critical in understanding whether the supervisor feedback environment is helpful or harmful for employee empowerment.
Thermal benefits of aggregation in a large marine endotherm: huddling in California sea lions
Authors: Liwanag H. E. M. , Oraze J. , Costa D. P. , Williams T. M. 
Published: March 2014

AbstractHuddling is an important behavior for many endotherms, and it is associated with both social interactions and physiological regulation. Sea lions are highly communal pinnipeds that often congregate in large numbers on coastal rookeries. While this behavior serves a social role, it also has the potential to change the microhabitat and thus the local thermal conditions experienced by the animals. However, the thermal consequences of huddling in pinnipeds have yet to be quantified despite a propensity for close proximity in some species. To investigate this, we quantified the huddling behavior of California sea lions, Zalophus californianus, by measuring the proximity of individuals from digital photographs, and determined the thermal microhabitat of huddles using an infrared temperature monitor. All animals were measured on San Nicolas Island (California, USA) for 6 days in winter (Tair = 13.2 ± 2.1°C) and 7 days in summer (Tair = 21.1 ± 3.4°C). We found that sea lion huddling behavior increased in colder weather, as determined from three indices. First, a larger proportion (up to 97%) of the animals participated in huddles rather than resting alone during the winter season (P = 0.010). Second, the number of animals per huddle was larger (reaching 172 animals) during the colder season (P = 0.019). Lastly, sea lions participating in this behavior huddled more tightly in cold temperatures (P = 0.023). The temperature differential between the animals' skin surface and that of the surrounding substrate was significantly greater (P < 0.001) for huddling sea lions (6.0 ± 3.6°C) than for animals resting alone (3.0 ± 2.8°C). Furthermore, this differential was inversely proportional to ambient temperatures. These results are consistent with huddling behavior in California sea lions providing a significant thermal benefit that likely shapes their social behavior on land.
The shape of things to come in the study of the origin of species?
Authors: Rogers Sean M. , Jamniczky Heather A. 
Published: March 2014

Perhaps Darwin would agree that speciation is no longer the mystery of mysteries that it used to be. It is now generally accepted that evolution by natural selection can contribute to ecological adaptation, resulting in the evolution of reproductive barriers and, hence, to the evolution of new species (Schluter & Conte ; Meyer ; Nosil ). From genes that encode silencing proteins that cause infertility in hybrid mice (Mihola et al. ), to segregation distorters linked to speciation in fruit flies (Phadnis & Orr ), or pollinator‐mediated selection on flower colour alleles driving reinforcement in Texan wildflowers (Hopkins & Rausher ), characterization of the genes that drive speciation is providing clues to the origin of species (Nosil & Schluter ). It is becoming apparent that, while recent work continues to overturn historical ideas about sympatric speciation (e.g. Barluenga et al. ), ecological circumstances strongly influence patterns of genomic divergence, and ultimately the establishment of reproductive isolation when gene flow is present (Elmer & Meyer ). Less clear, however, are the genetic mechanisms that cause speciation, particularly when ongoing gene flow is occurring. Now, in this issue, Franchini et al. () employ a classic genetic mapping approach augmented with new genomic tools to elucidate the genomic architecture of ecologically divergent body shapes in a pair of sympatric crater lake cichlid fishes. From over 450 segregating SNPs in an F2 cross, 72 SNPs were linked to 11 QTL associated with external morphology measured by means of traditional and geometric morphometrics. Annotation of two highly supported QTL further pointed to genes that might contribute to ecological divergence in body shape in Midas cichlids, overall supporting the hypothesis that genomic regions of large phenotypic effect may be contributing to early‐stage divergence in Midas cichlids.
Predator–prey trophic relationships in response to organic management practices
Authors: Schmidt Jason M. , Barney Sarah K. , Williams Mark A. , Bessin Ricardo T. , Coolong Timothy W. , Harwood James D. 
Published: March 2014

AbstractA broad range of environmental conditions likely regulate predator–prey population dynamics and impact the structure of these communities. Central to understanding the interplay between predator and prey populations and their importance is characterizing the corresponding trophic interactions. Here, we use a well‐documented molecular approach to examine the structure of the community of natural enemies preying upon the squash bug, Anasa tristis, a herbivorous cucurbit pest that severely hinders organic squash and pumpkin production in the United States. Primer pairs were designed to examine the effects of organic management practices on the strength of these trophic connections and link this metric to measures of the arthropod predator complex density and diversity within an experimental open‐field context. Replicated plots of butternut squash were randomly assigned to three treatments and were sampled throughout a growing season. Row‐cover treatments had significant negative effects on squash bug and predator communities. In total, 640 predators were tested for squash bug molecular gut‐content, of which 11% were found to have preyed on squash bugs, but predation varied over the season between predator groups (coccinellids, geocorids, nabids, web‐building spiders and hunting spiders). Through the linking of molecular gut‐content analysis to changes in diversity and abundance, these data delineate the complexity of interaction pathways on a pest that limits the profitability of organic squash production.
The advantages of going large: genome‐wide SNPs clarify the complex population history and systematics of the threatened western pond turtle
Authors: Spinks Phillip Q. , Thomson Robert C. , Shaffer H. Bradley 
Published: March 2014

AbstractAs the field of phylogeography has matured, it has become clear that analyses of one or a few genes may reveal more about the history of those genes than the populations and species that are the targets of study. To alleviate these concerns, the discipline has moved towards larger analyses of more individuals and more genes, although little attention has been paid to the qualitative or quantitative gains that such increases in scale and scope may yield. Here, we increase the number of individuals and markers by an order of magnitude over previously published work to comprehensively assess the phylogeographical history of a well‐studied declining species, the western pond turtle (Emys marmorata). We present a new analysis of 89 independent nuclear SNP markers and one mitochondrial gene sequence scored for rangewide sampling of >900 individuals, and compare these to smaller‐scale, rangewide genetic and morphological analyses. Our enlarged SNP data fundamentally revise our understanding of evolutionary history for this lineage. Our results indicate that the gains from greatly increasing both the number of markers and individuals are substantial and worth the effort, particularly for species of high conservation concern such as the pond turtle, where accurate assessments of population history are a prerequisite for effective management.
Bacillus subtilis spore protein SpoVAC functions as a mechanosensitive channel
Authors: Velásquez Jeanette , Schuurman‐Wolters Gea , Birkner Jan Peter , Abee Tjakko , Poolman Bert 
Published: March 2014

SummaryA critical event during spore germination is the release of Ca‐DPA (calcium in complex with dipicolinic acid). The mechanism of release of Ca‐DPA through the inner membrane of the spore is not clear, but proteins encoded by the Bacillus subtilis spoVA operon are involved in the process. We cloned and expressed the spoVAC gene in Escherichia coli and characterized the SpoVAC protein. We show that SpoVAC protects E. coli against osmotic downshift, suggesting that it might act as a mechanosensitive channel. Purified SpoVAC was reconstituted in unilamellar lipid vesicles to determine the gating mechanism and pore properties of the protein. By means of a fluorescence‐dequenching assay, we show that SpoVAC is activated upon insertion into the membrane of the amphiphiles lysoPC and dodecylamine. Patch clamp experiments on E. coli giant spheroplast as well as giant unilamellar vesicles (GUVs) containing SpoVAC show that the protein forms transient pores with main conductance values of about 0.15 and 0.1 nS respectively. Overall, our data indicate that SpoVAC acts as a mechanosensitive channel and has properties that would allow the release of Ca‐DPA and amino acids during germination of the spore.
TCA cycle activity in Staphylococcus aureus is essential for iron‐regulated synthesis of staphyloferrin A, but not staphyloferrin B: the benefit of a second citrate synthase
Authors: Sheldon Jessica R. , Marolda Cristina L. , Heinrichs David E. 
Published: March 2014

SummaryStaphylococcus aureus elaborates two citrate‐containing siderophores, staphyloferrin A (SA) and staphyloferrin B (SB), that enhance growth under iron‐restriction, yet, paradoxically, expression of the TCA cycle citrate synthase, CitZ, is downregulated during iron starvation. Iron starvation does, however, result in expression of SbnG, recently identified as a novel citrate synthase that is encoded from within the iron‐regulated SB biosynthetic locus, suggesting an important role for SbnG in staphyloferrin production. We demonstrate that during growth of S. aureus in iron‐restricted media containing glucose, SB is produced but, in contrast, SA production is severely repressed; accordingly, SB‐deficient mutants grow poorly in these media. Hypothesizing that reduced TCA cycle activity hinders SA production, we show that a citZ mutant is capable of SB synthesis, but not SA synthesis, providing evidence that SbnG does not generate citrate for incorporation into SA. A citZ sbnG mutant synthesizes neither staphyloferrin, is severely compromised for growth in iron‐restricted media, and is significantly more impaired for virulence than either of the single‐deletion mutants. We propose that SB is the more important of the two siderophores for S. aureus insofar as it is synthesized, and supports iron‐restricted growth, without need of TCA cycle activity.