bluuebunny/crossref_metadata_2025 huggingface dataset:
River temperature drives salmon survivorship: is it determined prior to ocean entry?
Authors: Morita Kentaro , Ayumi Nakashima , Kikuchi Motohiro
Published: January 2015

Early life is believed to be a critical stage for determining survivorship in all fish. Many studies have suggested that environmental conditions in the ocean determine the fry-to-adult survival rate of Pacific salmon but few investigations have been conducted on the importance of the brief freshwater period during the seaward migration on overall survivorship. Here, we found that most of the variation in survivorship of hatchery-reared chum salmon (
Oncorhynchus keta
) was explained by river temperature during the fry stage, despite spending most of their life (approx. 99%) at sea. After the annual release of a constant number of fry, the number of fry moving through the river at a downstream location varied greatly. The number of returning adults was positively correlated with the number of fry moving downstream. This result suggests that most salmon mortality occurred prior to ocean entry, and that short-term mortality in the river is a key factor determining major fluctuations in total mortality. Although marine mortality is often invoked in the literature as a key factor determining total mortality of chum salmon, attention should also be paid to freshwater mortality to understand the population dynamics of this species.
Opsin transcripts of predatory diving beetles: a comparison of surface and subterranean photic niches
Authors: Tierney Simon M. , Cooper Steven J. B. , Saint Kathleen M. , Bertozzi Terry , Hyde Josephine , Humphreys William F. , Austin Andrew D.
Published: January 2015

The regressive evolution of eyes has long intrigued biologists yet the genetic underpinnings remain opaque. A system of discrete aquifers in arid Australia provides a powerful comparative means to explore trait regression at the genomic level. Multiple surface ancestors from two tribes of diving beetles (Dytiscidae) repeatedly invaded these calcrete aquifers and convergently evolved eye-less phenotypes. We use this system to assess transcription of opsin photoreceptor genes among the transcriptomes of two surface and three subterranean dytiscid species and test whether these genes have evolved under neutral predictions. Transcripts forUV,long-wavelengthandciliary-typeopsins were identified from the surface beetle transcriptomes. Two subterranean beetles showed parallel loss of all opsin transcription, as expected under ‘neutral’ regressive evolution. The third speciesLimbodessus palmulaoidesretained transcription of along-wavelength opsin(lwop) orthologue, albeit in an aphotic environment. Tests of selection onlwopindicated no significant differences between transcripts derived from surface and subterranean habitats, with strong evidence for purifying selection acting onL. palmulaoides lwop. Retention of sequence integrity and the lack of evidence for neutral evolution raise the question of whether we have identified a novel pleiotropic role forlwop, or an incipient phase of pseudogene development.
Self-Incompatibility-Induced Programmed Cell Death in Field Poppy Pollen Involves Dramatic Acidification of the Incompatible Pollen Tube Cytosol
Authors: Wilkins Katie A. , Bosch Maurice , Haque Tamanna , Teng Nianjun , Poulter Natalie S. , Franklin-Tong Vernonica E.
Published: January 2015

Self-incompatibility (SI) is an important genetically controlled mechanism to prevent inbreeding in higher plants. SI involves highly specific interactions during pollination, resulting in the rejection of incompatible (self) pollen. Programmed cell death (PCD) is an important mechanism for destroying cells in a precisely regulated manner. SI in field poppy (Papaver rhoeas) triggers PCD in incompatible pollen. During SI-induced PCD, we previously observed a major acidification of the pollen cytosol. Here, we present measurements of temporal alterations in cytosolic pH ([pH]cyt); they were surprisingly rapid, reaching pH 6.4 within 10 min of SI induction and stabilizing by 60 min at pH 5.5. By manipulating the [pH]cyt of the pollen tubes in vivo, we show that [pH]cyt acidification is an integral and essential event for SI-induced PCD. Here, we provide evidence showing the physiological relevance of the cytosolic acidification and identify key targets of this major physiological alteration. A small drop in [pH]cyt inhibits the activity of a soluble inorganic pyrophosphatase required for pollen tube growth. We also show that [pH]cyt acidification is necessary and sufficient for triggering several key hallmark features of the SI  PCD signaling pathway, notably activation of a DEVDase/caspase-3-like activity and formation of SI-induced punctate actin foci. Importantly, the actin binding proteins Cyclase-Associated Protein and Actin-Depolymerizing Factor are identified as key downstream targets. Thus, we have shown the biological relevance of an extreme but physiologically relevant alteration in [pH]cyt and its effect on several components in the context of SI-induced events and PCD.
EBSD analysis of rhombohedral twinning in hematite crystals of naturally deformed iron formations
Authors: Ávila Carlos Fernando , Lagoeiro Leonardo , Ferreira Barbosa Paola , Graça Leonardo
Published: January 2015

The rhombohedral twinning in hematite has an important role in the accommodation of the deformation of hematite single crystals and hematite aggregates. It is a contact twinning and occurs as lamellae parallel to the \{10{\overline 1}2\} planes of hematite as a result of twin gliding on such planes. On account of the recent applications of electron backscatter diffraction (EBSD) techniques in a wide range of microstructural studies, the determination of symmetry operations that relate crystals in a deformed crystalline aggregate is crucial for the full textural characterization. This study presents an EBSD-based crystallographic analysis of the rhombohedral twinning on hematite crystals of a naturally deformed banded iron formation. Manipulations of theoretical pole figures depicting the symmetry relation of the rhombohedral twinning and misorientation and crystallographic data obtained by EBSD are used to establish the rotational relationship between twin and parent crystals. A method for determining pairs of axes and angles of rotation was developed which can be extended to any other twin laws or misorientation patterns in any other crystal system. It was found that the hematite rhombohedral twins are related to the parent crystal by an approximately 85° rotation about the 〈02{\overline 2}1〉 directions. Hence it could be determined that this consists of a macroscopic twinning element which is an alternative to the conventional ones used to describe the symmetry of the twin. It also matches microscopic twinning elements for the rhomb twinning law. Additionally, this method allows the determination of the crystallographic orientation of the twin lamellae and which particular 〈02{\overline 2}1〉 axis satisfies the 85°〈02{\overline 2}1〉 pair of rotation. The use of an unambiguous angle–axis pair of rotation allows the identification of twin boundaries in complex and finely grained aggregates and the distinction of twinning laws in a particular crystal.
Laboratory implementation of X-ray diffraction/scattering computed tomography
Authors: Cersoy Sophie , Leynaud Olivier , Álvarez-Murga Michelle , Martinetto Pauline , Bordet Pierre , Boudet Nathalie , Chalmin Emilie , Castets Géraldine , Hodeau Jean Louis
Published: January 2015

This article demonstrates the possibility to perform X-ray diffraction/scattering computed tomography experiments with a laboratory diffraction setup. This technique is useful to characterize samples with inhomogeneities on a length scale of a couple of hundred micrometres. Furthermore, the method can be applied to preliminary phase-selective imaging prior to higher-resolution characterization using synchrotron radiation. This article presents the results of test experiments carried out on a rhombohedral C60sample previously studied at the ESRF.
Real structure of Ge4Bi2Te7: refinement on diffuse scattering data with the 3D-ΔPDF method
Authors: Urban Philipp , Simonov Arkadiy , Weber Thomas , Oeckler Oliver
Published: January 2015

Metastable Ge4Bi2Te7is highly disordered; the average structure corresponds to the rocksalt type. The diffraction pattern shows diffuse streaks interconnecting Bragg reflections along all cubic 〈111〉 directions. These streaks exhibit satellite-like maxima and arise from vacancy ordering in non-periodically spaced defect layers. The atom layers near these vacancy layers are displaced with respect to the average structure: they tend to form α-GeTe-type double layers. The three-dimensional difference pair distribution function (3D-ΔPDF) method yields quantitative information on the distribution of defect layer spacings, which peaks at a value corresponding to Ge3Bi2Te6building blocks. The cation distribution along with the displacement of the atom layers is refined as well, using a least-squares approach. Bi concentrates on cation positions next to the vacancy layers.
Mechanism of preferential nucleation of [\bf 1{\overline 1}0{\overline 3}]-oriented GaN twins on an SiO2-patternedm-plane sapphire substrate
Authors: Yoon Hansub , Jue Miyeon , Lee Hyemi , Lee Sanghwa , Kim Chinkyo
Published: January 2015

The mechanism of preferential nucleation of [1{\overline 1}0{\overline 3}]-oriented GaN faceted twins on an SiO2-patternedm-plane sapphire substrate was investigated. Each variant of twins, which were enclosed byc- andm-facets, was observed to be preferentially nucleated over the opposite sides of an SiO2pattern. It was hypothesized, from the fact that the same method of Legendre transformation is applied to a Wulff plot and a kinetic Wulff plot to determine the growth morphology of a crystalline domain, that theeffectivesurface energy ofc- andm-facets would be proportional to the growth rate of the respective facet. On the basis of this hypothesis, minimization of the effective surface energy of a nucleated domain was proposed as a mechanism of preferential nucleation. This proposed mechanism successfully explained the preferential nucleation behaviour.
Diffuse X-ray scattering from ion-irradiated materials: a parallel-computing approach
Authors: Channagiri J. , Boulle A. , Debelle A.
Published: January 2015

A computational method for the evaluation of the two-dimensional diffuse X-ray scattering distribution from irradiated single crystals is presented. A Monte Carlo approach is used to generate the displacement field in the damaged crystal. This step makes use of vector programming and multiprocessing to accelerate the computation. Reciprocal space maps are then computed using GPU-accelerated fast Fourier transforms. It is shown that this procedure speeds up the calculation by a factor of ∼190 for a crystal containing 109unit cells. The potential of the method is illustrated with two examples: the diffuse scattering from a single crystal containing (i) a non-uniform defect depth distribution (with a potentially bimodal defect size distribution) and (ii) spatially correlated defects exhibiting either long-range or short-range ordering with varying positional disorder.
Full-field energy-dispersive powder diffraction imaging using laboratory X-rays
Authors: Egan Christopher K. , Jacques Simon D. M. , Wilson Matthew D. , Veale Matthew C. , Seller Paul , Withers Philip J. , Cernik Robert J.
Published: January 2015

A laboratory instrument with the ability to spatially resolve energy-dispersed X-ray powder diffraction patterns taken in a single snapshot has been developed. The experimental arrangement is based on a pinhole camera coupled with a pixelated spectral X-ray detector. Collimation of the diffracted beam is defined by the area of the footprint of a detector pixel and the diameter of the pinhole aperture. Each pixel in the image, therefore, contains an energy-dispersed powder diffraction pattern. This new X-ray imaging technique enables spatial mapping of crystallinity, crystalline texture or crystalline phases from within a sample. Validation of the method has been carried out with a back-to-back comparison with crystalline texture mapping local to a friction stir weld in an aluminium alloy taken using synchrotron radiation.
Crystal structure determination and refinementviaSIR2014
Authors: Burla Maria Cristina , Caliandro Rocco , Carrozzini Benedetta , Cascarano Giovanni Luca , Cuocci Corrado , Giacovazzo Carmelo , Mallamo Mariarosaria , Mazzone Annamaria , Polidori Giampiero
Published: January 2015

SIR2014is the latest program of theSIRsuite for crystal structure solution of small, medium and large structures. A variety of phasing algorithms have been implemented, bothab initio(standard or modern direct methods, Patterson techniques,Vive la Différence) and non-ab initio(simulated annealing, molecular replacement). The program contains tools for crystal structure refinement and for the study of three-dimensional electron-density mapsviasuitable viewers.
Mathematical aspects of molecular replacement. III. Properties of space groups preferred by proteins in the Protein Data Bank
Authors: Chirikjian G. , Sajjadi S. , Toptygin D. , Yan Y.
Published: January 2015

The main goal of molecular replacement in macromolecular crystallography is to find the appropriate rigid-body transformations that situate identical copies of model proteins in the crystallographic unit cell. The search for such transformations can be thought of as taking place in the coset space Γ\Gwhere Γ is the Sohncke group of the macromolecular crystal andGis the continuous group of rigid-body motions in Euclidean space. This paper, the third in a series, is concerned with viewing nonsymmorphic Γ in a new way. These space groups, rather than symmorphic ones, are the most common ones for protein crystals. Moreover, their properties impact the structure of the space Γ\G. In particular, nonsymmorphic space groups contain both Bieberbach subgroups and symmorphic subgroups. A number of new theorems focusing on these subgroups are proven, and it is shown that these concepts are related to the preferences that proteins have for crystallizing in different space groups, as observed in the Protein Data Bank.
Partial order among the 14 Bravais types of lattices: basics and applications
Authors: Grimmer Hans
Published: January 2015

NeitherInternational Tables for Crystallography(ITC) nor available crystallography textbooks state explicitly which of the 14 Bravais types of lattices are special cases of others, although ITC contains the information necessary to derive the result in two ways, considering either the symmetry or metric properties of the lattices. The first approach is presented here for the first time, the second has been given by Michael Klemm in 1982. Metric relations between conventional bases of special and general lattice types are tabulated and applied to continuous equi-translation phase transitions.
Statistical tests against systematic errors in data sets based on the equality of residual means and variances from control samples: theory and applications
Authors: Henn Julian , Meindl Kathrin
Published: January 2015

Statistical tests are applied for the detection of systematic errors in data sets from least-squares refinements or other residual-based reconstruction processes. Samples of the residuals of the data are tested against the hypothesis that they belong to the same distribution. For this it is necessary that they show the same mean values and variances within the limits given by statistical fluctuations. When the samples differ significantly from each other, they are not from the same distribution within the limits set by the significance level. Therefore they cannot originate from a single Gaussian function in this case. It is shown that a significance cutoff results in exactly this case. Significance cutoffs are still frequently used in charge-density studies. The tests are applied to artificial data with and without systematic errors and to experimental data from the literature.
Reading experiences influencing the acceptance of e-book devices
Authors: Park Eunil , Sung Jungyeon , Cho Kwangsu
Published: January 2015

Purpose

– This paper aims to explore users’ perception of, and then intention toward using, e-book devices as new reading devices, based upon an integrated technology acceptance model (TAM), reading engagement based upon flow theory and readability. The recent introduction of e-book devices has drastically changed the way people access and use reading content. However, few studies have explored the impact of reading experience on acceptance of e-book devices.

Design/methodology/approach

– A total of 219 participants participated in a survey after using e-book devices to analyze the research model.

Findings

– This study confirmed the crucial roles played by viewing experience, perceived mobility, perceived behavioral control, skill and readability. Also perceived usefulness and text satisfaction were found to have a positive and significant association with acceptance of e-book devices.

Research limitations/implications

– Implications and suggestions for researchers and manufacturers are also addressed in the present study.

Originality/value

– The current study focused on how actual reading experiences using e-book devices influences acceptance of e-book devices, through the triangular integrated model of TAM, reading engagement and readability features, and investigating users’ reading experience on the basis of responses to the characteristics of e-book devices.
Web content and design trends of Alabama academic libraries
Authors: Wilson Daniel Earl
Published: January 2015

Purpose

– This paper aims to evaluate the website content of Alabama academic libraries to examine their services, content and compliance with design and accessibility standards.

Design/methodology/approach

– A content analysis was conducted on 24 academic library websites discovered through Jeanne Burke’s Higher Education Directory and the Alabama Colleges directory website. All data were collected within a month.

Findings

– Study data revealed that while academic libraries are offering more online services, many continue to lack certain services or fail to implement basic web design and accessibility standards.

Research limitations/implications

– Inclusion into the study was limited to the independent library websites of Alabama institutions offering four-year degree courses and content data discoverable within three clicks of the home page. Future studies might identify why certain libraries lack reference chat services, social media accounts and/or certain accessibility accommodations. Additional research might evaluate multilingual websites and their methods for providing language options.

Practical implications

– The results of this study should assist in the evaluation of library websites and increase awareness of design and accessibility standards, enabling designers and policy makers to improve upon future website designs.

Originality/value

– This study presents a depth of evaluation and currency unseen in most web content analyses. The extent of this study should provide librarians, web designers, and library policy makers with a suitable comparison for website projects and evaluations.
Effectiveness of information technology in reducing corruption in China
Authors: Xinli Hu
Published: January 2015

Purpose

– The purpose of this paper is to examine the effectiveness of information technology in reducing corruption in China. Meanwhile this paper explores whether electronic monitoring systems (EMS) can be evaluated in terms of the DeLone and McLean information systems (IS) success model.

Design/methodology/approach

– The status of the EMS in five cities is first proposed, and then a model of e-government system success is designed to evaluate the EMS. Data are obtained from 387 civil servants in the supervision agencies. Then the effectiveness of EMS in reducing corruption is deeply assessed, and the DeLone and McLean IS success model is validated.

Findings

– The findings show that the application of EMS has a positive effect on reducing corruption. IT thus has the potential to reduce corruption, but the institution and the people are more important.

Originality/value

– Although many theories about reducing corruption have been proposed, the EMS application in reducing corruption has seldom been addressed. This study is the first, to the author's knowledge, to examine EMS and corruption reduction from the point of view of the IS success model.
Usage patterns of Punjab University Library website: a transactional log analysis study
Authors: Arshad Alia , Ameen Kanwal
Published: January 2015

Purpose

– This paper aims to assess the usage patterns of a university library website to find out user’s behaviour of monthly use, its top most used resources and services and search phrases used to reach the library website.

Design/methodology/approach

– Transactional log analysis (TLA) – an unobtrusive research method – was used to identify and analyse data of website-using patterns. The log data of website use from January 2011 to March 2011 were analysed for this study.

Findings

– The findings of this study revealed that the university library website was heavily used on campus by users; however, it was used by a significant number of clients residing off-campus. Free scholarly journals, resources downloaded, e-journals, e-books and donated personal collections were among the top most used resources and services. However, free scholarly journals were used more than subscribed e-journals accessible on-campus only.

Originality/value

– This study first used the TLA method to trace user behaviour of website use in a local scenario. Assessing the usage of e-resources is imperative to determine the effectiveness of the library website in providing these services to its on-campus and distant users. The findings of this study are valuable for librarians and webmasters of the library website to redesign and reorient their services.
Role and users’ approach to social networking sites (SNSs): a study of universities of North India
Authors: Singh K P , Gill Malkeet Singh
Published: January 2015

Purpose

– The purpose of this paper is to evaluate and assess the awareness and extent of the use of social networking sites (SNSs) by the students and research scholars of universities of North India.

Design/methodology/approach

– The study is a questionnaire-based survey on the usage of SNSs among the students and research scholars of the universities of North India. The data of the study were collected through questionnaires, which were personally distributed to the identified population, i.e. undergraduate students, postgraduate students and research scholars, by the authors. The survey was based on a sample of 610 questionnaires; of which, 486 questionnaires were received, having a response rate of 79.67 per cent.

Findings

– The study showed that all the respondents were found to be aware of and making use of such applications in their academic affairs. It was revealed from the study that Facebook is the most popular SNS by all categories of respondents. To determine the purpose of SNSs, it emerged that SNSs are mostly used for entertainment and communication. The study also found that the majority of respondents were aware about the security aspects of SNSs. It signifies that excessive time consumption and fear of misusing personal information were the major hurdles in the way of accessing SNSs.

Research limitations/implications

– The study covers the students and research scholars of select universities of North India. It also signifies the use of SNSs in their research and academic environment.

Originality/value

– The paper provides reliable and authentic data. The study is worth, justifiable and enlightens the salient findings on the topic, which will be very useful for researchers in this area.
Political skill in job negotiations: a two-study constructive replication
Authors: Solga Marc , Betz Jaqueline , Düsenberg Moritz , Ostermann Helen
Published: January 2015

Purpose

– This paper aims to investigate the effects of political skill in a specific workplace setting – the job negotiation. The authors expected negotiator political skill to be positively related to distributive negotiation outcome, problem-solving as a negotiation strategy to mediate this relationship and political skill to also moderate – that is amplify – the link between problem-solving and negotiation outcome.

Design/methodology/approach

– In Study 1, a laboratory-based negotiation simulation was conducted with 88 participants; the authors obtained self-reports of political skill prior to the negotiation and – to account for non-independence of negotiating partners’ outcome – used the Actor–Partner Interdependence Model for data analysis. Study 2 was carried out as a real-life negotiation study with 100 managers of a multinational corporation who were given the opportunity to re-negotiate their salary package prior to a longer-term foreign assignment. Here, the authors drew on two objective measures of negotiation success, increase of annual gross salary and additional annual net benefits.

Findings

– In Study 1, the initial hypothesis – political skill will be positively related to negotiator success – was fully supported. In Study 2, all three hypotheses (see above) were fully supported for additional annual net benefits and partly supported for increase of annual gross salary.

Originality/value

– To the authors' best knowledge, this paper presents the first study to examine political skill as a focal predictor variable in the negotiation context. Furthermore, the studies also broaden the emotion-centered approach to social effectiveness that is prevalent in current negotiation research.
Did anyone notice the transformation of adult social care? An analysis of Safeguarding Adult Board Annual Reports
Authors: Manthorpe Jill , Stevens Martin , Samsi Kritika , Aspinal Fiona , Woolham John , Hussein Shereen , Ismail Mohamed , Baxter Kate
Published: January 2015

Purpose

– The purpose of this paper is to report on a part of a study examining the interrelationships between personalisation and safeguarding practice. Specifically the authors aimed to examine how safeguarding practice is affected by the roll out of personalisation in adult social care, particularly when the adult at risk has a personal budget or is considering this.

Design/methodology/approach

– A sample of annual reports from Adult Safeguarding Boards in England was accessed for content analysis covering the period 2009-2011. One part of this sample of local authorities was selected at random; the other authorities selected had been early adopters of personalisation. The reports were analysed using a pro forma to collect salient information on personalisation that was cross-referenced to identify common themes and differences.

Findings

– The authors found variable mentions of personalisation as part of the macro policy context reported in the annual reviews, some examples of system or process changes at mezzo level where opportunities to discuss the interface were emerging, and some small reports of training and case accounts relevant to personalisation. Overall these two policy priorities seemed to be more closely related than had been found in earlier research on the interface between adult safeguarding and personalisation.

Research limitations/implications

– There was wide variation in the annual reports in terms of detail, size and content, and reports for only one year were collected. Developments may have taken place but might not have been recorded in the annual reports so these should not be relied upon as complete accounts of organisational or practice developments.

Practical implications

– Authors of Safeguarding Adults Board reports may benefit from learning that their reports may be read both immediately and potentially in the future. They may wish to ensure their comments on current matters will be intelligible to possible future readers and researchers.

Originality/value

– There does not appear to have been any other previous study of Safeguarding Adult Boards’ annual reports. Documentary analysis at local level is under-developed in safeguarding studies.
Improving food safety – replicating the Abu Dhabi success story
Authors: Taylor Eunice , Taylor Joanne
Published: January 2015

Purpose

– This paper aims to summarise and draw conclusions from the contents of this Worldwide Hospitality and Tourism Themes issue: What action can government take to improve food safety in a diverse and multi-cultural hospitality industry? The issue presents a comprehensive government strategy for improving food safety management standards across the hospitality industry. It is the seventh and concluding article in the collection.

Design/methodology/approach

– The article revisits the strategic question posed by this theme issue: What action can government take to improve food safety in a diverse and multi-cultural hospitality industry? Using the Abu Dhabi success story, it considers the extent to which the lessons and successes in Abu Dhabi could be applied in other multi-cultural settings.

Findings

– The article provides a detailed and practical response to the strategic question, highlighting the action that can be taken and demonstrating key success factors. In particular, it acknowledges the importance of utilising international benchmarking, key guidance documents, in-depth culturally appropriate research, extensive industry involvement and a project team with the relevant expertise.

Originality/value

– The article provides an overview of the extensive work done in Abu Dhabi to improve food safety standards, while also highlighting success factors that can be applied by other governments and within other projects. It provides an outline of the policy guidelines needed and the action points for the industry to bring about effective long-term improvement across the whole hospitality sector.
Signal architecture: temporal variability and individual consistency of multiple sexually selected signals
Authors: Chaine Alexis S. , Lyon Bruce E.
Published: January 2015

Multiple signals should be favoured when the benefit of additional signals outweigh their costs. Despite increased attention on multiple‐signalling systems, few studies have focused on signal architecture to understand the potential information content of multiple signals.

To understand the patterns of signal plasticity and consistency over the lifetime of individuals we conducted a longitudinal study of multiple signals known to be under sexual selection in male lark buntings, Calamospiza melanocorys.

Within years, we found extensive among‐individual variation in all four plumage ornaments we measured. Surprisingly, there were few correlations among these signals, suggesting that individuals contain a mosaic of signals. Signals were only moderately repeatable across years, which indicates some signal plasticity or age related change. In some years, the direction of change in particular signals relative to the previous year was consistent for most individuals in the population, suggesting that broad scale ecological factors affected the ornament phenotype. Different ornaments were affected by different ecological or social factors because the population‐wide shift in a given signal was independent of change in other signals.

Our combined results suggest that different signals—including different components of the same color patch in some cases—provide diverse and independent information about the individual to signal receivers in the context of sexual selection.
Trans‐generational priming of resistance in wild flour beetles reflects the primed phenotypes of laboratory populations and is inhibited by co‐infection with a common parasite
Authors: Tate Ann T. , Graham Andrea L.
Published: January 2015

Trans‐generational priming renders offspring of immune‐challenged parents less susceptible to disease‐induced mortality, and has been demonstrated in a variety of arthropod taxa under controlled laboratory conditions. However, relatively little is known about the applicability of these laboratory results to priming in wild populations, especially in the context of environmental variables like maternal co‐infection and potential trade‐offs with other life history traits.

We performed nearly parallel trans‐generational priming experiments on laboratory and wild strains of Tribolium beetles against the bacterial pathogen Bacillus thuringiensis (Bt). We investigated the impact of maternal immune challenge on offspring survival and development time, as well as the correlation between development and survival by priming status. Furthermore, we manipulated wild beetle parental co‐infection with a gregarine parasite that was prevalent in the wild population in order to determine the impact of co‐infection on the efficacy of trans‐generational priming.

Trans‐generational priming resulted in a large but birth order‐dependent acceleration of offspring development time, and enhanced offspring survival against infection, in both laboratory and wild populations. However, adult parental co‐infection with gut protozoa severely curtailed primed offspring survival against Bt infection.

These results suggest that shifts in life history traits associated with trans‐generational priming in laboratory model systems extend to wild populations. These traits, including survival, development, and interference from co‐infection, are important parameters for predicting the impact of priming on disease dynamics in the wild.
Vitamin E deficiency in last‐laid eggs limits growth of yellow‐legged gull chicks
Authors: Parolini Marco , Romano Maria , Caprioli Manuela , Rubolini Diego , Saino Nicola
Published: January 2015

Parental phenotype and environment have cascading effects on offspring performance. Such ‘maternal’ effects are often mediated by the size and quality of the eggs in terms of maternal endogenous substances or exogenous components.

Maternal effects can function to maximize parental fitness via adaptive allocation of components among sibling eggs. In birds, the often documented variation in concentration of egg dietary antioxidants or other egg compounds with laying order may thus reflect adaptive parental favouritism or maternal physiological constraints.

Vitamins are found in the yolk at high concentrations and accomplish important physiological functions. Tocopherols (‘vitaminE’) have major roles in antioxidant protection, but the consequence of variation in their concentration for chick phenotype has never been experimentally investigated under a natural selection regime.

In the yellow‐legged gull (Larus michahellis) free‐ranging population we studied, vitaminEconcentration and egg size decline from the first to the third (last) egg. Chicks from third eggs are smaller and have lower viability compared to those from sibling eggs. Here, we tested the effect of injecting a physiological dose of vitaminEin the egg yolk on chick body size at hatching by comparison with chicks from sham‐injected eggs.

As predicted, chicks from vitaminEinjected third eggs were larger than chicks from control third eggs, whereas vitaminEhad no effect on chicks from the other eggs. Thus, vitaminEinjection disrupted the brood size hierarchy according to laying order normally found in this species.

In species that adopt a brood reduction strategy, differential allocation of vitaminEto the eggs can contribute to establish a hierarchy of reproductive value among progeny members functioning to maximize parental fitness. The present results therefore have general implications for the study of the evolution of maternal effects mediated by transfer of potentially limiting maternal antioxidants to the eggs.
Under the influence: sublethal exposure to an insecticide affects personality expression in a jumping spider
Authors: Royauté Raphaël , Buddle Christopher M. , Vincent Charles
Published: January 2015

Consistent behavioural differences between individuals have far‐reaching implications for ecology and evolution, including how populations cope with increasing anthropogenic changes, notably pesticides. Although sublethal doses of insecticides are known to alter behaviour, current studies on the relationship between toxicants and behaviour tend to ignore effects on individual variation.

Our objective was to determine whether sublethal exposure to an organophosphate insecticide could affect the consistency of individual behaviour and disrupt behavioural correlations, in a jumping spider occurring in agroecosystems. Adults of the jumping spider Eris militaris (Araneae: Salticidae) were scored by an open‐field and a prey‐capture assay, each conducted pre‐ and post‐ exposure to the organophosphate insecticide phosmet. Half of the individuals received no exposure to the insecticide to provide a control group. We then estimated the changes in repeatability, a measure of the extent of personality differences, and in behavioural correlations between control and insecticide‐treated groups.

Although insecticide exposure had no discernable effects on the population's average behaviours, insecticide‐exposed individuals showed an average of 23% lower repeatability and the correlation between activity and prey capture was more strongly collapsed in females.

Our results provide clear evidence that exposure to sublethal doses of insecticides on an important arthropod predator in agroecosystems causes substantial alteration of personality differences even in absence of a population‐wide shift in behaviour. This suggests that insecticide effects are more complex than previously thought and indicates high variation in the way individuals coped with insecticidal exposure.

By altering the consistency of behavioural traits and their correlations, exposure to sublethal concentrations of insecticides can have subtle effects on behavioural expression, which may ultimately affect biocontrol performance in an important arthropod predator in agroecosystems. Our study calls for an increasing focus on individual behavioural variation when testing the effects of pesticides on non‐targeted fauna.
Conquering the world in leaps and bounds: hopping locomotion in toads is actually bounding
Authors: Reilly Stephen M. , Montuelle Stephane J. , Schmidt Andre , Naylor Emily , Jorgensen Michael E. , Halsey Lewis G. , Essner Richard L.
Published: January 2015

While most frogs maximize jump distance as an escape behaviour, toads have traded jump distance for endurance with a strategy of hopping repeatedly. This strategy has enabled toads to expand across the continents as one of the most diverse groups of anurans. Multiple studies have revealed physiological endurance adaptations for sustained hopping in toads, however, the kinematics of their sequential hopping behaviour, per se, has not been studied.

We compared kinematics and forces of single hops and multiple hopping sequences and quantified field performance of hopping behaviours in free ranging toads of three species and discovered a novel aspect of locomotion adaptation that adds another facet to their exceptional terrestrial locomotor abilities.

We found that bouts of repeated hopping are actually a series of bounding strides where toads rotate on their hands and then land on their extended their feet and jump again without stopping. In addition, free‐ranging toads appear to use bounding locomotion more frequently than single hops. Bounding in toads has the advantage of maintaining velocity and producing longer jump distances. In comparison to single hops, cyclic bounding steps reduce energy expenditure and appear to provide limb loading dynamics better suited for potential cycling of elastic energy from stride to stride than would be possible with repeated single hops.

This is the first case of the common use of a bounding gait outside of mammals. Bounding adds a key terrestrial locomotor trait to the toad's phenotype that may help explain their history of global expansion and the challenges to modern faunas as introduced toads rapidly invade new ecosystems today.
Adjustments in habitat selection to changing availability induce fitness costs for a threatened ungulate
Authors: Losier Chrystel L. , Couturier Serge , St‐Laurent Martin‐Hugues , Drapeau Pierre , Dussault Claude , Rudolph Tyler , Brodeur Vincent , Merkle Jerod A. , Fortin Daniel
Published: January 2015

Functional responses in habitat selection occur when individuals adjust their selection of habitat features as a function of the availability of those features. Functional responses in habitat selection are generally assumed to be fitness‐rewarding tactics and are used to guide conservation actions. Fitness consequences of functional responses, however, have rarely been evaluated.

Eighty‐three caribou were followed with GPS collars to establish the link between functional responses in habitat selection and adult female survival, a strong fitness correlate for caribou. We measured how caribou avoidance of mixed/deciduous stands and 6‐ to 20‐year‐old clear‐cuts varied with the proportion of 6‐ to 20‐year‐old clear‐cuts within their 100% minimal convex polygon (MCP), and if these functional responses were linked to survival. Mixed/deciduous stands and 6‐ to 20‐year‐old clear‐cuts are risky for caribou because they are selected by moose, thereby attracting wolves and increasing predation risk for caribou.

Caribou avoided mixed/deciduous stands, especially when 6‐ to 20‐year‐old clear‐cuts comprised a large proportion of their MCP, but this functional response did not differ between caribou that died and those that survived. When the proportion of 6‐to 20‐year‐old clear‐cuts in the MCP was low, caribou generally had low odds of occurring near 6‐ to 20‐year‐old clear‐cuts. However, when the proportion of clear‐cuts in the MCP was relatively high, caribou that strongly increased their odds of being near 6‐ to 20‐year‐old clear‐cuts were generally those that died.

Synthesis and applications. Assessing the fitness consequences of how animals respond to habitat disturbances is central to wildlife conservation. We demonstrate that distinct functional responses in habitat selection involve different mortality risks and that population dynamics should depend on the frequency of the different tactics observed within populations. Individuals that persistently select riskier areas should be important drivers of population decline. Caribou mortality could be reduced by decreasing the appeal of 6‐ to 20‐year‐old clear‐cuts for moose by removing deciduous vegetation through cleaning, which should reduce the selection of wolves for these stands. Removing deciduous vegetation should be especially effective in areas where those clear‐cuts comprise a large proportion of the landscape, because this is where a subset of the caribou population experiences high mortality rates by selecting 6‐ to 20‐year‐old clear‐cuts.
Novel host‐specific iron acquisition system in the zoonotic pathogenVibrio vulnificus
Authors: Pajuelo David , Lee Chung‐Te , Roig Francisco J. , Hor Lien‐I. , Amaro Carmen
Published: January 2015

Vibrio vulnificusis a marine bacterium associated with human and fish (mainly farmed eels) diseases globally known as vibriosis. The ability to infect and overcome eel innate immunity relies on a virulence plasmid (pVvbt2) specific for biotype 2 (Bt2) strains. In the present study, we demonstrated that pVvbt2 encodes a host‐specific iron acquisition system that depends on an outer membrane receptor for eel transferrin calledVep20. The inactivation ofvep20did not affect either bacterial growth in human plasma or virulence for mice, while bacterial growth in eel blood/plasma was abolished and virulence for eels was significantly impaired. Furthermore,vep20is an iron‐regulated gene overexpressed in eel blood during artificially induced vibriosis bothin vitroandin vivo. Interestingly, homologues tovep20were identified in the transferable plasmids of two fish pathogen species of broad‐host range,Vibrio harveyi(pVh1) andPhotobacterium damselaesubsp.damselae(pPHDD1). These data suggest thatVep20 belongs to a new family of plasmid‐encoded fish‐specific transferrin receptors, and the acquisition of these plasmids through horizontal gene transfer is likely positively selected in the fish‐farming environment. Moreover, we proposeFtbp (fish transferrin binding proteins) as a formal name for this family of proteins.
‘Ménage à trois’: a selfish genetic element uses a virus to propagate within Thermotogales
Authors: Lossouarn Julien , Nesbø Camilla L. , Mercier Coraline , Zhaxybayeva Olga , Johnson Milo S. , Charchuck Rhianna , Farasin Julien , Bienvenu Nadège , Baudoux Anne‐Claire , Michoud Grégoire , Jebbar Mohamed , Geslin Claire
Published: January 2015

Prokaryotic viruses play a major role in the microbial ecology and evolution. However, the virosphere associated with deep‐sea hydrothermal ecosystems remains largely unexplored. Numerous instances of lateral gene transfer have contributed to the complex and incongruent evolutionary history of Thermotogales, an order well represented in deep‐sea hydrothermal vents. The presence of clustered regularly interspaced short palindromic repeats (CRISPR) loci has been reported in all Thermotogales genomes, suggesting that these bacteria have been exposed to viral infections that could have mediated gene exchange. In this study, we isolated and characterized the first virus infecting bacteria from the order Thermotogales, Marinitoga piezophila virus 1 (MPV1). The host, Marinitoga piezophila is a thermophilic, anaerobic and piezophilic bacterium isolated from a deep‐sea hydrothermal chimney. MPV1 is a temperate Siphoviridae‐like virus with a 43.7 kb genome. Surprisingly, we found that MPV1 virions carry not only the viral DNA but preferentially package a plasmid of 13.3 kb (pMP1) also carried by M. piezophila. This ‘ménage à trois’ highlights potential relevance of selfish genetic elements in facilitating lateral gene transfer in the deep‐sea biosphere.
Enzymes of the benzoyl‐coenzyme A degradation pathway in the hyperthermophilic archaeon Ferroglobus placidus
Authors: Schmid Georg , René Sandra Bosch , Boll Matthias
Published: January 2015

The Fe(III)‐respiring Ferroglobus placidus is the only known archaeon and hyperthermophile for which a complete degradation of aromatic substrates to CO2 has been reported. Recent genome and transcriptome analyses proposed a benzoyl‐coenzyme A (CoA) degradation pathway similar to that found in the phototrophic Rhodopseudomonas palustris, which involves a cyclohex‐1‐ene‐1‐carboxyl‐CoA (1‐enoyl‐CoA) forming, ATP‐dependent key enzyme benzoyl‐CoA reductase (BCR). In this work, we demonstrate, by first in vitro studies, that benzoyl‐CoA is ATP‐dependently reduced by two electrons to cyclohexa‐1,5‐dienoyl‐CoA (1,5‐dienoyl‐CoA), which is further degraded by hydration to 6‐hydroxycyclohex‐1‐ene‐1‐carboxyl‐CoA (6‐OH‐1‐enoyl‐CoA); upon addition of NAD+, the latter was subsequently converted to β‐oxidation intermediates. The four candidate genes of BCR were heterologously expressed, and the enriched, oxygen‐sensitive enzyme catalysed the two‐electron reduction of benzoyl‐CoA to 1,5‐dienoyl‐CoA. A gene previously assigned to a 2,3‐didehydropimeloyl‐CoA hydratase was heterologously expressed and shown to act as a typical 1,5‐dienoyl‐CoA hydratase that does not accept 1‐enoyl‐CoA. A gene previously assigned to a 1‐enoyl‐CoA hydratase was heterologously expressed and identified to code for a bifunctional crotonase/3‐OH‐butyryl‐CoA dehydrogenase. In summary, the results consistently provide biochemical evidence that F. placidus and probably other archaea predominantly degrade aromatics via the Thauera/Azoarcus type and not or only to a minor extent via the predicted R. palustris‐type benzoyl‐CoA degradation pathway.