bluuebunny/crossref_metadata_2025 huggingface dataset:
Psychological trajectories in the year after a newly diagnosed seizure
Authors: Velissaris Sarah L. , Saling Michael M. , Newton Mark R. , Berkovic Samuel F. , Wilson Sarah J.
Published: September 2012

Purpose:  Underdiagnosed depression and anxiety are well‐recognized issues in chronic epilepsy, but the evolution of these symptoms after diagnosis is not well understood. We aimed to identify mood trajectories after a first seizure, and to examine factors impacting these trajectories.

Methods:  Seventy‐four patients were evaluated at 1, 3, and 12 months with (1) the Hospital Anxiety and Depression Scale, and (2) a semistructured interview assessing patients’ initial psychological reaction to the seizure at 1 month (limited vs. pervasive loss of control). The SAS Institute’s TRAJ data modelling procedure was employed to delineate trajectories.

Key Findings:  Two depression and three anxiety trajectories were identified, with significant overlap. The majority of patients (∼74%) followed a trajectory with low depression throughout the study, and either low or moderate anxiety. A minority followed trajectories with high depression and anxiety from diagnosis (∼16%). Patients with high levels of distress were adversely affected by seizure recurrence and antiepileptic drugs (AEDs), whereas those with low levels were not. Trajectories were predicted by the patient’s sense of loss of control early after diagnosis and were weakly related to demographic and medical variables (age, gender, education, relationship status, psychiatric history, and prior epileptic events).

Significance:  Methods that account for heterogeneity in patient responses are critical for developing a clinically relevant understanding of adjustment after a newly diagnosed seizure. Most patients appear to be resilient in the face of early seizures, whereas those at risk of longer‐term psychological difficulties may be evident from diagnosis. Early screening for depression and anxiety is warranted.
Coordinability and Consistency in Accident Causation and Prevention: Formal System Theoretic Concepts for Safety in Multilevel Systems
Authors: Cowlagi Raghvendra V. , Saleh Joseph H.
Published: September 2012

Although a “system approach” to accidents in sociotechnical systems has been frequently advocated, formal system theoretic concepts remain absent in the literature on accident analysis and system safety. To address this gap, we introduce the notions of coordinability and consistency from the hierarchical and multilevel systems theory literature. We then investigate the applicability and the importance of these concepts to accident causation and safety. Using illustrative examples, including the worst disaster in aviation history, and recent incidents in the United States of aircraft clipping each other on the tarmac, we propose that the lack of coordinability is a fundamental failure mechanism causing or contributing to accidents in multilevel systems. We make a similar case for the lack of consistency. Coordinability and consistency become ingredients for accident prevention, and their absence fundamental failure mechanisms that can lead to system accidents. Finally, using the concepts introduced in this work, we identify several venues for further research, including the development of a theory of coordination in multilevel systems, the investigation of potential synergies between coordinability, consistency, and the high reliability organizations paradigm, and the possibility of reframing the view that “sloppy management is the root cause of many industrial accidents” as one of lack of coordinability and/or consistency between management and operations. By introducing and expanding on the concepts of coordinability and consistency, we hope to contribute to the thinking about, and the to language of, accident causation, and prevention and to add to the intellectual toolkit of safety professionals and academics.
Financial Expertise as an Arms Race
Authors: GLODE VINCENT , GREEN RICHARD C. , LOWERY RICHARD
Published: September 2012

We show that firms intermediating trade have incentives to overinvest in financial expertise. In our model, expertise improves firms’ ability to estimate value when trading a security. Expertise creates asymmetric information, which, under normal circumstances, works to the advantage of the expert as it deters opportunistic bargaining by counterparties. This advantage is neutralized in equilibrium, however, by offsetting investments by competitors. Moreover, when volatility rises the adverse selection created by expertise triggers breakdowns in liquidity, destroying gains to trade and thus the benefits that firms hope to gain through high levels of expertise.
The Meanings of Democracy in Venezuela: Citizen Perceptions and Structural Change
Authors: Canache Damarys
Published: September 2012

Throughout Latin America, democratic political structures reflect liberal conceptualizations of democracy. Since the election of Hugo Chávez, Venezuela has emerged as an exception, with President Chávez sponsoring initiatives designed to foster participatory democracy. This article draws on the Venezuelan case in an effort to gain insight on the malleability of citizens' definitions of and attitudes toward democracy. Two key findings emerge. First, in data gathered ten years into the Chávez presidency, the vast majority of Venezuelans still define democracy in liberal terms, whereas relatively few have embraced participatory conceptualizations. Second, although Venezuelans as a whole are highly supportive of democracy as a form of government, no evidence is found that either support for Chávez or defining democracy in terms of participation corresponds with higher favorability toward democracy. Together, these findings suggest that Venezuela's political transformation has produced little or no discernible effect on mass sentiment regarding democracy.
How Do Distrust and Anxiety Affect Saving Behavior?
Authors: Hayhoe Celia R. , Cho Soo Hyun , DeVaney Sharon A. , Worthy Sheri Lokken , Kim Jinhee , Gorham Elizabeth
Published: September 2012

Using scales developed from a modified Yamauchi and Templer's Money Attitudes Scale (1982), this research examined how distrust and anxiety, demographic factors, and financial management behavior were associated with being a regular saver among low‐ and moderate‐income households. Data were collected online. The national sample consisted of 749 respondents. The results of the Ordinary Least Squares regression on the financial management behavior score showed that those with higher levels of distrust and lower levels of anxiety tended to engage in more recommended financial management behaviors. The results of the logistic regression on saving regularly showed that anxiety and financial management behaviors were associated with savings behavior. The results of hierarchical logistic regressions showed that those who practiced more recommended financial management behaviors and those who had lower levels of anxiety were more likely to save regularly. Also, those with more income and more net worth were more likely to save regularly. Male respondents were more likely to save regularly than female respondents. As age increased, respondents were less likely to save regularly.
Identification of Tool Marks of a Sickle on a Telephone Cable
Authors: Kumar Rajesh , Patial Naseeb , Singh Sanjeev
Published: September 2012

Linkage of a cutting tool (a sickle) with a telephone cable of 100 pairs of copper wires is reported in a case of theft of a telephone cable. Telephone cables contain numerous insulated copper wires of small diameter inside an outer covering and are stolen for the relatively precious copper. The cutting pattern of the cable can only point to the type of the tool but because of the large number of copper wires, it is practically difficult to make a definite linkage with the tool used to cut the cable by comparing the tool marks. The present work reports the successful attempt of the authors in establishing a definite linkage of a stolen telephone cable with a sickle recovered from the suspects. Spot microchemical test was performed for detection of copper on the blade of the sickle, and then tool mark comparison was performed to link the tool marks on the metal strip inside the outer covering of the cable to the blade of the sickle.
Assessing children's dental anxiety: a systematic review of current measures
Authors: Porritt Jenny , Buchanan Heather , Hall Melanie , Gilchrist Fiona , Marshman Zoe
Published: September 2012

The reliable assessment of children's dental anxiety can have many benefits for the dental team, service providers and dental public health practitioners. This study aimed to identify and evaluate self‐report measures, which are available to assess children's dental anxiety. Systematic searches of the literature between 1998 and 2011 were conducted to identify relevant studies. The properties of each measure (reliability and validity) were assessed, and measures were evaluated against a theoretical framework of dental anxiety. Executing the search strategy generated 498 articles and of these 60 studies met all of the inclusion criteria. Seven ‘trait’ and two ‘state’ measures of dental anxiety had been employed to assess children's dental anxiety over the past decade. Reliability and validity estimates for the most widely used measures were good; however, many questionnaires had a limited focus in the aspects of anxiety they assessed. The paper summarizes the measures of children's dental anxiety which may be most useful for a number of different purposes and populations.
Lipid economy, flight activity and reproductive behaviour in the speckled wood butterfly: on the energetic cost of territory holding
Authors: Vande Velde Lesley , Van Dyck Hans
Published: September 2012

Insect flight is a highly energy demanding type of locomotion. In butterflies, males may locate females by different behavioural tactics. The tactics correspond to different flight types that, in turn, are assumed to reflect different energetic costs. Costs need to be considered to fully understand the pay‐offs of co‐existing alternative tactics relative to the environmental context and the phenotypes of the individuals. We addressed the issue in the speckled wood Pararge aegeria, in which males either adopt a territorial wait‐and‐fight tactic (i.e. territorial perching) in a sunlit patch on the forest floor, or a fly‐and‐search tactic to locate females in a wider area of the forest (i.e. patrolling). Perching corresponds to high frequency of take‐off flights and aerial combats with high levels of manoeuvrability and is assumed to be energetically more costly than longer, continuous flights at lower speed in patrollers. We tested the effect of different flight activity levels and of the behavioural tactics on lipid reserves and lipid use in males by laboratory and outdoor cage experiments. Low‐activity males that had access to honey water were capable of synthesizing lipids; their lipid reserves increased with age. The effect disappeared in males that actively flew in the outdoor cages. Lipid reserves decreased significantly faster in territorial perching males compared to non‐perching males, but resting metabolic rate did not differ between the alternative behavioural tactics. Territorial perching males had larger flight muscle ratio (i.e. thorax/body mass) than non‐perching males. We discuss the evidence of the physiological costs of perching relative to the co‐existence of perching and patrolling tactics.
Competitive outcomes between two exotic invaders are modified by direct and indirect effects of a native conifer
Authors: Metlen Kerry L. , Aschehoug Erik T. , Callaway Ragan M.
Published: September 2012

When organisms interact in multi‐species groups, the direct effects of facilitation and competition can be modified by indirect interactions. We explored multispecies interactions among the native Pinus ponderosa, the invasive annual grass Bromus tectorum, and the invasive forb Centaurea stoebe in intermountain prairie of the northern Rocky Mountains. Centaurea is much less abundant under Pinus than in surrounding open grassland and Bromus is more abundant under Pinus. We found that the more fertile soil associated with Pinus facilitated both invasive species and did not alter competitive outcomes. Pinus litter and litter leachate inhibited both species, but litter also shifted competitive outcomes in favor of Bromus and against Centaurea. The effects of Pinus litter leachate were also strong and leachate eliminated the competitive effect of Centaurea on Bromus while not changing the competitive effect of Bromus on Centaurea. There are many other ways that Pinus may affect understory composition, but by altering the competitive playing field through leaf litter Pinus appears to indirectly facilitate Bromus by more strongly inhibiting Centaurea chemically, an unusual case of a native inhibiting an invader through allelopathy. Our results also provide an unexpected and novel perspective on indirect interactions among competitors, but not through intransitive competitive relationships. Instead, one species (Pinus) strongly ‘modified’ interactions between two other species in addition to disproportionately affecting one species more than another.
Salinity tolerance and the decoupling of resource axis plant traits
Authors: Eallonardo Anthony S. , Leopold Donald J. , Fridley Jason D. , Stella John C.
Published: September 2012

Questions

What ecophysiological relationships underlie the sorting of species from freshwater to inland salt marsh communities? Which plant functional trade‐offs are present along a gradient of low to high salinity?

Location

New York State, USA.

Methods

We evaluated changes in species composition and plant functional traits along resource and salinity gradients at three sites using principal components, correlation and fourth‐corner analyses.

Results

Analyses of plant traits suggested an axis of specialization that was related to salinity tolerance and distinct from a resource axis describing a spectrum of plant traits associated with resource acquisition and retention. Plant species with low scores on the salinity axis had highest abundance in the most saline plots and tended to have small leaf size, high leaf nitrogen per area (Narea), C4 photosynthesis and succulence. Whereas C4 photosynthesis, leaf size and leaf succulence were each linked to patterns of species presence and relative cover along soil Na:K and electrical conductivity (EC) gradients, leaf Narea was most positively correlated with salinity tolerance. Leaf size also played a key role in species sorting along each of the environmental gradients examined in this study (soil EC, Na:K, flooding duration, soil extractable calcium and magnesium and soil N concentrations).

Conclusions

Salinity tolerance is an alternative axis of plant specialization. The overall trade‐off underlying salinity tolerance is inefficient N use in exchange for efficient water use and tolerance of toxic soil salinity levels. This research further elucidates the processes of community assembly along environmental gradients, trade‐offs associated with salinity tolerance, and provides baseline information for wetland restoration.
Dating, Sex, and Schooling in Urban Kenya
Authors: Clark Shelley , Mathur Rohini
Published: September 2012

Completion of secondary school is increasingly viewed as a desirable life goal for young men and women in urban Kenya. Yet achieving this goal often conflicts with other key transitions to adulthood, such as becoming sexually active, marrying, having children, and finding employment. Drawing upon exceptionally rich life‐history calendar data from young people in Kisumu, Kenya, we explore how the timing and sequencing of key transitions affects the likelihood of secondary school completion. Conversely, we also examine how school enrollment and performance affect the timing of sexual initiation. Our findings indicate that sexual activity and the transition toward family formation are largely incompatible with young women's schooling. For men, however, romantic and sexual partnerships have no impact on schooling unless a partner becomes pregnant. Instead, paid employment appears to be least compatible with continued education.
Improving the attractiveness of an emergency medicine career to medical students: An exploratory study
Authors: Celenza Antonio , Bharath Jude , Scop Jason
Published: September 2012

Objectives

To describe perceptions of medical students and emergency doctors towards careers in emergency medicine (EM), and to identify influences on career choice.

Methods

A prospective, cross‐sectional questionnaire study was performed in three EDs. The instrument used Likert‐type items addressing: factors important in the choice of a career, factors offered by a career in EM, and opinions of EM. EM consultants and registrars and a cohort of final‐year medical students participated.

Results

Overall, 22 consultants, 30 registrars and 164 students completed the questionnaire (77.1% overall response). Student interest in an EM career increased from 10/161 (6.2% [95% CI 3.0–11.1%]) before, to 26/137 (19.0% [95% CI 12.8–26.6%]) after an EM attachment (P = 0.0014). The highest proportion of students chose work–life balance as being an important factor for career choice (143/163 students, 87.7% [95% CI 81.2–92.6%]). Compared with consultants and registrars, students had negative perceptions about lifestyle factors that EM offered, as well as about the future of the specialty, job security and workplace stress. Some students also preferred careers with opportunities for research, subspecialty practice, and better pay and conditions, yet perceived EM as not offering these factors. Students considered EM as an acute, procedural, public hospital specialty, with diverse patient problems and minimal continuity of care. Smaller proportions of students considered these factors important for career choice.

Conclusion

Increasing the attractiveness of a career in EM requires changing student perceptions of lifestyle and satisfaction benefits, access to EM subspecialties, increasing ED research, information about job security, and improved work conditions.
Methods of estimating marine mammal diets: A review of validation experiments and sources of bias and uncertainty
Authors: Bowen W. D. , Iverson S. J.
Published: September 2012

Diet estimation in marine mammals relies on indirect methods including recovery of prey hard parts from stomachs and feces, quantitative fatty acid signature analysis (QFASA), stable isotope mixing models, and identification of prey DNA in stomach contents and feces. Experimental evidence (9 species/13 studies) shows that digestion strongly influences the proportion and size of otoliths that can be recovered in feces. Number correction factors (NCF) and digestion coefficients have been experimentally determined to reduce the biases in fecal analysis. Correction factors and coefficients have not been determined for diet estimated from stomach contents. QFASA estimates which prey species and amounts must have been eaten to account for the fatty acid composition of the predator. Experimental studies on mammals and seabirds (9 species/10 studies) indicate that accurate estimates of diet can be determined using QFASA. Stable isotope mixing models provide rather coarse taxonomic resolution of diet composition. Prey DNA analysis shows promise as a method to estimate the species composition of diet, but further development and testing is needed to validate its use. Obtaining a representative sample from marine mammal populations is a significant challenge. Therefore, the use of complementary methods is recommended to obtain the most informative results.
Method for evaluating flood disaster reduction measures in alluvial plains
Authors: Taki K. , Matsuda T. , Ukai E. , Nishijima T. , Egashira S.
Published: September 2012

With attention focused on flood hazard risk from place to place on a whole flood plain before and after flood hazard reduction and mitigation countermeasures are implemented, the present study proposes a method for evaluating flood hazard risk described using a local inundation depth and its frequency of occurrence. The method is composed of a rainfall run‐off model, a 1‐D channel flow model, a depth‐integrated 2‐D flood model, and several sub‐models, such as of a potential damage curve and an evacuation rating curve. To test the applicability of the proposed method, a flood plain located in the northern lake area of Shiga prefecture is chosen for discussion. The spatial distribution of damage resulting from each flood is thus evaluated before and after countermeasures are implemented.
Embolisation of hypervascular bone tumours: A pictorial essay with literature review
Authors: Lau Vince , Sun Michael , Chu Ferdinand
Published: September 2012

Bone tumours, either primary or secondary, can present in various debilitating manners, including pain and pathological fracture. The situation is particularly problematic when the tumours are hypervascular, and located in regions where a high risk of neurological compromise is anticipated during operation, such as in the spine or sacrum. In such situations, bone tumour embolisation is a useful and effective adjunctive treatment for reducing intra‐operative blood loss. This is particularly relevant in primary bone tumours such as giant cell tumours and metastatic renal cell and thyroid tumours. With a proper pre‐embolisation angiogram and knowledge of anatomy, careful selective cannulation of the arterial supplies and experience in using embolic agents, the risks of non‐target embolisation can be kept to minimum and the best result achieved.
Existing Regulation of Exempt Wells in the United States
Authors: Richardson Jesse J.
Published: September 2012

Exempt domestic water well provisions exist in sixteen states and allow landowners to use water wells producing relatively small amounts of water or water wells used for domestic or other specific purposes to avoid certain regulatory requirements. Exempt wells provisions apply mainly in the west, where most states use the prior appropriation rule (“first in time, first in right”) for ground water rights. Critics voice concerns over implications ranging from land use planning to water supply. This article explores existing state regulation and finds that the term “exempt well” is a misnomer. The vast majority of states impose numerous restrictions on exempt wells. Existing regulations include limitations on the quantity, location, and amount of irrigation use. Other provisions address construction standards, required filing of information and other practices. The review of regulations suggests that many steps to mitigate the impact of exempt wells are already in place.
Evaluation of co‐oximetry for the measurement of methemoglobin in rainbow trout (Oncorhynchus mykiss) and values in 3 salmonid species
Authors: Saunders Janet , Speare David J. , McConkey Sandra
Published: September 2012

Background

Methemoglobin (metHb) is oxidized hemoglobin that cannot reversibly bind oxygen, and concentrations in healthy fish have been reported to be 0.6–24.8% compared with 0–3% in healthy mammals. In fish, metHb has been measured using spectrophotometric methods using potassium cyanide (KCN), but not using co‐oximetry, which is the preferred method for human samples.

Objectives

The aims of this study were to evaluate co‐oximetry as a method for measuring metHb in Oncorhynchus mykiss, compare co‐oximetry with a KCN spectrophotometric method, and establish reference values for metHb concentrations as measured using co‐oximetry in O mykiss, Salmo salar, and Salvelinus fontinalis.

Methods

Blood samples from healthy female O mykiss, female S salar, and female and male S fontinalis were prepared by separation and washing of erythrocytes in Tris/NaCl/EDTA buffer followed by lysis in Tris/EDTA buffer. MetHb concentrations were measured using an IL‐682 co‐oximeter. Moderate and high metHb concentrations were produced in vitro using NaNO2.

Results

At low concentrations of methemoglobin, CVs for intraday precision were 10.3% and 53.9% using co‐oximetry and the KCN spectrophotometric method, respectively. The CV for interday precision using co‐oximetry was 11.9%. MetHb concentrations were stable in whole blood stored at 4°C for 7 days. MetHb concentrations were linear up to 58.2% (r = .99) using co‐oximetry and 27.5% (r = .94) using the KCN method. The lower limit of detection for metHb was 0.02 g/dL using co‐oximetry. Reference values for metHb concentrations using co‐oximetry in O mykiss, S salar, and S fontinalis (n = 40 of each species) were 0.6–1.8%, 1.1–1.9%, and 1.1–4.0%, respectively.

Conclusions

Co‐oximetry can be used to measure methemoglobin in blood from fish, in particular in O mykiss, and is better than the KCN spectrophotometric method. Reference values for methemoglobin concentrations in O mykiss, S salar, and S fontinalis are similar to those in mammals.
The Collaborative Assessment and Management of Suicidality (CAMS): An Evolving Evidence‐Based Clinical Approach to Suicidal Risk
Authors: Jobes David A.
Published: September 2012

The Collaborative Assessment and Management of Suicidality (CAMS) is an evidence‐based clinical intervention that has significantly evolved over 25 years of clinical research. CAMS is best understood as a therapeutic framework that emphasizes a unique collaborative assessment and treatment planning process between the suicidal patient and clinician. This process is designed to enhance the therapeutic alliance and increase treatment motivation in the suicidal patient. Central to the CAMS approach is the use of the Suicide Status Form (SSF), which is a multipurpose clinical assessment, treatment planning, tracking, and outcome tool. The original development of CAMS was largely rooted in SSF‐based quantitative and qualitative assessment of suicidal risk. As this line of research progressed, CAMS emerged as a problem‐focused clinical intervention that is designed to target and treat suicidal “drivers” and ultimately eliminate suicidal coping. To date, CAMS (and the clinical use of the SSF) has been supported by six published correlational studies and one randomized clinical trial (RCT). Currently, two well‐powered RCTs are under way, and various new CAMS‐related projects are also being pursued. The clinical and empirical evolution of CAMS—how it was developed and what are the next steps for this clinical approach–are described here.
XBP1 depletion precedes ubiquitin aggregation and Golgi fragmentation in TDP‐43 transgenic rats
Authors: Tong Jianbin , Huang Cao , Bi Fangfang , Wu Qinxue , Huang Bo , Zhou Hongxia
Published: September 2012

Protein inclusion is a prominent feature of neurodegenerative diseases including frontotemporal lobar degeneration (FTLD) that is characterized by the presence of ubiquitinated TDP‐43 inclusion. Presence of protein inclusions indicates an interruption to protein degradation machinery or the overload of misfolded proteins. In response to the increase in misfolded proteins, cells usually initiate a mechanism called unfolded protein response (UPR) to reduce misfolded proteins in the lumen of endoplasmic reticules. Here, we examined the effects of mutant TDP‐43 on the UPR in transgenic rats that express mutant human TDP‐43 restrictedly in the neurons of the forebrain. Over‐expression of mutant TDP‐43 in rats caused prominent aggregation of ubiquitin and remarkable fragmentation of Golgi complexes prior to neuronal loss. While ubiquitin aggregates and Golgi fragments were accumulating, neurons expressing mutant TDP‐43 failed to up‐regulate chaperones residing in the endoplasmic reticules and failed to initiate the UPR. Prior to ubiquitin aggregation and Golgi fragmentation, neurons were depleted of X‐box‐binding protein 1 (XBP1), a key player of UPR machinery. Although it remains to determine how mutation of TDP‐43 leads to the failure of the UPR, our data demonstrate that failure of the UPR is implicated in TDP‐43 pathogenesis.
Cytopathology of Tomato torrado virus Infection in Tomato and Nicotiana benthamiana
Authors: Zielińska Lidia , Byczyk Julia , Rymelska Natalia , Borodynko Natasza , Pospieszny Henryk , Hasiów‐Jaroszewska Beata
Published: September 2012

Electron microscopy studies were carried out to investigate the cytopathological changes induced in tomato leaves by Tomato torrado virus (ToTV) that infects tomato plants worldwide causing severe necrotic symptoms. Plants infected with one of the Polish isolates of ToTV were used for cytopathological research. The results revealed severe cellular alterations, especially in Solanum lycopersicum. Moreover, it was shown that crystalline aggregates of virions occurred not only within the phloem cells as it has been previously reported.
Colony growth of corals transplanted for restoration depends on their site of origin and environmental factors
Authors: Forrester Graham E. , Taylor Kerianne , Schofield Stephanie , Maynard Amy
Published: September 2012

We determined that growth differences among coral fragments transplanted for restoration were influenced by both source population and environmental factors. In two common garden experiments, storm‐generated fragments of Acropora palmata were transplanted from two source populations in the British Virgin Islands to a restoration site (a ‘common garden’) that lacked A. palmata. In the first experiment, colonies from different sources grew at different rates in the first year after transplanting, suggesting either genetic differences among source populations or enduring acclimation to conditions at the source site. No differences in growth among source populations were detected in the second common garden experiment. To isolate environmental effects on growth, we subdivided fragments from three source populations to create genetically identical pieces that were attached separately at both source and restoration sites. Genetically identical pieces from all source populations grew slightly faster at their source than at the restoration site, implying a subtle home‐site advantage. Overall, our results suggest that matching environmental conditions at source and restoration sites may increase the success of restoration projects.
SNP‐array reveals genome‐wide patterns of geographical and potential adaptive divergence across the natural range of Atlantic salmon (Salmo salar)
Authors: Bourret Vincent , Kent Matthew P. , Primmer Craig R. , Vasemägi Anti , Karlsson Sten , Hindar Kjetil , McGinnity Philip , Verspoor Eric , Bernatchez Louis , Lien Sigbjørn
Published: September 2012

Atlantic salmon (Salmo salar) is one of the most extensively studied fish species in the world due to its significance in aquaculture, fisheries and ongoing conservation efforts to protect declining populations. Yet, limited genomic resources have hampered our understanding of genetic architecture in the species and the genetic basis of adaptation to the wide range of natural and artificial environments it occupies. In this study, we describe the development of a medium‐density Atlantic salmon single nucleotide polymorphism (SNP) array based on expressed sequence tags (ESTs) and genomic sequencing. The array was used in the most extensive assessment of population genetic structure performed to date in this species. A total of 6176 informative SNPs were successfully genotyped in 38 anadromous and freshwater wild populations distributed across the species natural range. Principal component analysis clearly differentiated European and North American populations, and within Europe, three major regional genetic groups were identified for the first time in a single analysis. We assessed the potential for the array to disentangle neutral and putative adaptive divergence of SNP allele frequencies across populations and among regional groups. In Europe, secondary contact zones were identified between major clusters where endogenous and exogenous barriers could be associated, rendering the interpretation of environmental influence on potentially adaptive divergence equivocal. A small number of markers highly divergent in allele frequencies (outliers) were observed between (multiple) freshwater and anadromous populations, between northern and southern latitudes, and when comparing Baltic populations to all others. We also discuss the potential future applications of the SNP array for conservation, management and aquaculture.
Genomic scan for single nucleotide polymorphisms reveals patterns of divergence and gene flow between ecologically divergent species
Authors: Stölting Kai N. , Nipper Rick , Lindtke Dorothea , Caseys Celine , Waeber Stephan , Castiglione Stefano , Lexer Christian
Published: September 2012

Recent advances in population genomics have triggered great interest in the genomic landscape of divergence in taxa with ‘porous’ species boundaries. One important obstable of previous studies of this topic was the low genomic coverage achieved. This issue can now be overcome by the use of ‘next generation’ or short‐read DNA‐sequencing approaches capable of assaying many thousands of single nucleotide polymorphisms (SNPs) in divergent species. We have scanned the ‘porous’ genomes of Populus alba and Populus tremula, two ecologically divergent hybridizing forest trees, using >38 000 SNPs assayed by restriction site associated DNA (RAD) sequencing. Windowed analyses indicate great variation in genetic divergence (e.g. the proportion of fixed SNPs) between species, and these results are unlikely to be strongly biased by genomic features of the Populus trichocarpa reference genome used for SNP calling. Divergence estimates were significantly autocorrelated (P < 0.01; Moran's I up to 0.6) along 11 of 19 chromosomes. Many of these autocorrelations involved low divergence blocks, thus suggesting that allele sharing was caused by recurrent gene flow rather than shared ancestral polymorphism. A conspicuous low divergence block of three megabases was detected on chromosome XIX, recently put forward as an incipient sex chromosome in Populus, and was largely congruent with introgression of mapped microsatellites in two natural hybrid zones (N > 400). Our results help explain the origin of the ‘genomic mosaic’ seen in these taxa with ‘porous’ genomes and suggest rampant introgression or extensive among‐species conservation of an incipient plant sex chromosome. RAD sequencing holds great promise for detecting patterns of divergence and gene flow in highly divergent hybridizing species.
NaxD is a deacetylase required for lipid A modification and Francisella pathogenesis
Authors: Llewellyn Anna C. , Zhao Jinshi , Song Feng , Parvathareddy Jyothi , Xu Qian , Napier Brooke A. , Laroui Hamed , Merlin Didier , Bina James E. , Cotter Peggy A. , Miller Mark A. , Raetz Christian R. H. , Weiss David S.
Published: September 2012

Modification of specific Gram‐negative bacterial cell envelope components, such as capsule, O‐antigen and lipid A, are often essential for the successful establishment of infection. Francisella species express lipid A molecules with unique characteristics involved in circumventing host defences, which significantly contribute to their virulence. In this study, we show that NaxD, a member of the highly conserved YdjC superfamily, is a deacetylase required for an important modification of the outer membrane component lipid A in Francisella. Mass spectrometry analysis revealed that NaxD is essential for the modification of a lipid A phosphate with galactosamine in Francisella novicida, a model organism for the study of highly virulent Francisella tularensis. Significantly, enzymatic assays confirmed that this protein is necessary for deacetylation of its substrate. In addition, NaxD was involved in resistance to the antimicrobial peptide polymyxin B and critical for replication in macrophages and in vivo virulence. Importantly, this protein is also required for lipid A modification in F. tularensis as well as Bordetella bronchiseptica. Since NaxD homologues are conserved among many Gram‐negative pathogens, this work has broad implications for our understanding of host subversion mechanisms of other virulent bacteria.
Pseudomonas aeruginosa lipopolysaccharide inhibits Candida albicans hyphae formation and alters gene expression during biofilm development
Authors: Bandara H.M.H.N. , K Cheung B.P. , Watt R.M. , Jin L.J. , Samaranayake L.P.
Published: September 2012

Elucidation of bacterial and fungal interactions in multispecies biofilms will have major impacts on understanding the pathophysiology of infections. The objectives of this study were to (i) evaluate the effect of Pseudomonas aeruginosa lipopolysaccharide (LPS) on Candida albicans hyphal development and transcriptional regulation, (ii) investigate protein expression during biofilm formation, and (iii) propose likely molecular mechanisms for these interactions. The effect of LPS on C. albicans biofilms was assessed by XTT‐reduction and growth curve assays, light microscopy, scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM). Changes in candidal hypha‐specific genes (HSGs) and transcription factor EFG1 expression were assessed by real‐time polymerase chain reaction and two‐dimensional gel electrophoresis, respectively. Proteome changes were examined by mass spectrometry. Both metabolic activities and growth rates of LPS‐treated C. albicans biofilms were significantly lower (P < 0.05). There were higher proportions of budding yeasts in test biofilms compared with the controls. SEM and CLSM further confirmed these data. Significantly upregulated HSGs (at 48 h) and EFG1 (up to 48 h) were noted in the test biofilms (P < 0.05) but cAMP levels remained unaffected. Proteomic analysis showed suppression of candidal septicolysin‐like protein, potential reductase‐flavodoxin fragment, serine hydroxymethyltransferase, hypothetical proteins Cao19.10301(ATP7), CaO19.4716(GDH1), CaO19.11135(PGK1), CaO19.9877(HNT1) by P. aeruginosa LPS. Our data imply that bacterial LPS inhibit C. albicans biofilm formation and hyphal development. The P. aeruginosa LPS likely target glycolysis‐associated mechanisms during candidal filamentation.
Safe perioperative pediatric care around the world
Authors: Ivani Giorgio , Walker Isabeau , Enright Angela
Published: September 2012

Pediatric anesthesia is no longer a small subspecialty, but an important sector where developments in the new century have brought effective and safe management to children in the perioperative period. Unfortunately, what is common daily practice in the high‐income countries with all the guidelines, checklists, instruments, and dedicated pediatric anesthesiologists is often only a dream in the low‐ and middle‐income countries where the basic anesthesia services for improving the high rate of morbidity and mortality still are lacking. Anesthesia given by nonphysicians, with no monitoring, lack of elementary supplies, poor control of infections and hemorrhage, and no water or electricity are very often the ‘usual’ conditions. The World Health Organization is working hard to offer teams, basic equipments, and teaching and what is needed to offer children of these countries the same opportunities given in the industrialized countries. Other projects such as the Lifebox Project have a similar aim. This paper outlines some of what organizations are doing around the world, with different strategies all having the same target: safe pediatric anesthesia.
Pediatric airway management: current practices and future directions
Authors: Sunder Rani A. , Haile Dawit T. , Farrell Patrick T. , Sharma Anshuman
Published: September 2012

Management of a pediatric airway can be a challenge, especially for the nonpediatric anesthesiologists. Structured algorithms for an unexpected difficult pediatric airway have been missing so far. A recent step wise algorithm, based on the Difficult Airway society (DAS) adult protocol, is a step in the right direction. There have been some exciting advances in development of pediatric extra‐glottic devices for maintaining ventilation, and introduction of pediatric versions of new ‘non line of sight’ laryngoscopes and optical stylets. The exact role of these devices in routine and emergent situations is still evolving. Recent advances in simulation technology has become a valuable tool in imparting psychomotor and procedural skills to trainees and allied healthcare workers. Moving toward the goal of eliminating serious adverse events during the management of routine and difficult pediatric airway, authors propose that institutions develop a dedicated Difficult Airway Service comprising of a team of experts in advanced airway management.
Identification of an additional protein involved in mannan biosynthesis
Authors: Wang Yan , Mortimer Jennifer C. , Davis Jonathan , Dupree Paul , Keegstra Kenneth
Published: September 2012

Galactomannans comprise a β‐1,4‐mannan backbone substituted with α‐1,6‐galactosyl residues. Genes encoding the enzymes that are primarily responsible for backbone synthesis and side‐chain addition of galactomannans were previously identified and characterized. To identify additional genes involved in galactomannan biosynthesis, we previously performed deep EST profiling of fenugreek (Trigonella foenum‐graecum L.) seed endosperm, which accumulates large quantities of galactomannans as a reserve carbohydrate during seed development. One of the candidate genes encodes a protein that is likely to be a glycosyltransferase. Because this protein is involved in mannan biosynthesis, we named it ‘mannan synthesis‐related’ (MSR). Here, we report the characterization of a fenugreek MSR gene (TfMSR) and its two Arabidopsis homologs, AtMSR1 and AtMSR2. TfMSR was highly and specifically expressed in the endosperm. TfMSR, AtMSR1 and AtMSR2 proteins were all determined to be localized to the Golgi by fluorescence confocal microscopy. The level of mannosyl residues in stem glucomannans decreased by approximately 40% for Arabidopsis msr1 single T‐DNA insertion mutants and by more than 50% for msr1 msr2 double mutants, but remained unchanged for msr2 single mutants. In addition, in vitro mannan synthase activity from the stems of msr1 single and msr1 msr2 double mutants also decreased. Expression of AtMSR1 or AtMSR2 in the msr1 msr2 double mutant completely or partially restored mannosyl levels. From these results, we conclude that the MSR protein is important for mannan biosynthesis, and offer some ideas about its role.
Calculation of Steady and Periodic Unsteady Blade Surface Heat Transfer in Separated Transitional Flow
Authors: Pacciani Roberto , Rubechini Filippo , Arnone Andrea , Lutum Ewald
Published: September 2012

In this work, aerothermal investigations of a highly loaded HP turbine blade are presented. The purpose of such investigations is to improve the physical understanding of the heat transfer in separated flow regions, with the final goal of optimizing cooling configurations for aerodynamically highly loaded turbine designs. The analysis is focused on the T120 cascade, that was recently tested experimentally in the framework of the European project AITEB-2 (Aero-thermal Investigation of Turbine Endwalls and Blades). Such a cascade has a relatively low solidity that is responsible for the formation of a laminar separation bubble on the suction side of the blade. Separated-flow transition and transonic conditions downstream of the throat result in a flow configuration that is very challenging for traditional RANS solvers. Moreover, the separated flow transition pattern was found to have a strong impact on both the aerodynamic and thermal aspects. The study was carried out using a novel three-equation, transition-sensitive, turbulence model. It is based on the coupling of an additional transport equation for the laminar kinetic energy to the Wilcox k - ω model. Such an approach allows one to take into account the increase of the nonturbulent fluctuations in the pretransitional and transitional region. Comprehensive aerodynamic and heat transfer measurements were available for comparison purposes. In particular, heat transfer measurements cover different Mach and Reynolds numbers, in both steady and periodic unsteady inflow conditions. A detailed comparison between measurements and computations is presented, and the impact of transition-related aspects on the surface heat transfer is discussed.
Substrate temperature and electron fluence effects on metallic films created by electron beam induced deposition
Authors: Rosenberg Samantha G. , Landheer Kees , Hagen Cornelis W. , Fairbrother D. Howard
Published: September 2012

Using three different precursors [MeCpPtMe3, Pt(PF3)4, and W(CO)6], an ultra-high vacuum surface science approach has been used to identify and rationalize the effects of substrate temperature and electron fluence on the chemical composition and bonding in films created by electron beam induced deposition (EBID). X-ray photoelectron spectroscopy data indicate that the influence of these two processing variables on film properties is determined by the decomposition mechanism of the precursor. For precursors such as MeCpPtMe3 that decompose during EBID without forming a stable intermediate, the film's chemical composition is independent of substrate temperature or electron fluence. In contrast, for Pt(PF3)4 and W(CO)6, the initial electron stimulated deposition event in EBID creates surface bound intermediates Pt(PF3)3 and partially decarbonylated Wx(CO)y species, respectively. These intermediates can react subsequently by either thermal or electron stimulated processes. Consequently, the chemical composition of EBID films created from either Pt(PF3)4 or W(CO)6 is influenced by both the substrate temperature and the electron fluence. Higher substrate temperatures promote the ejection of intact PF3 and CO ligands from Pt(PF3)3 and Wx(CO)y intermediates, respectively, improving the film's metal content. However, reactions of Pt(PF3)3 and Wx(CO)y intermediates with electrons involve ligand decomposition, increasing the irreversibly bound phosphorous content in films created from Pt(PF3)4 and the degree of tungsten oxidation in films created from W(CO)6. Independent of temperature effects on chemical composition, elevated substrate temperatures (>25 °C) increased the degree of metallic character within EBID deposits created from MeCpPtMe3 and Pt(PF3)4.