bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimizing the Time for Developmental Dysplasia of the Hip Screening
Authors: Gokharman Fatma Dilek , Aydin Sonay , Fatihoglu Erdem , Ergun Elif , Kosar Pinar Nercis
Published: March 2018

Introduction

Developmental dysplasia of the hip (DDH) is still a common and important disorder of childhood, with a prevalence of 0.1 to 2/1000 children. Using ultrasonography (US) in screening of DDH reduces the rates of open reductions and complications. In the current study, we aim to detect the optimal time for US examination for detecting DDH to prevent unnecessary repeating US examinations and treatments.

Methods

Children referred to US examination for a healthy child screening program, according to the health policy of our country, are included in the current prospective study. Both hips of each child were sonographically examined by the same radiologist using Graf's method at 4th, 8th, 12th weeks of life.

Results

A total of 2020 hips of 1010 children were examined. Fourth-week US results can predict 12th-week results (right hip: sensitivity 100%, specificity 75.7%; left hip: sensitivity 100%, specificity 78.3%). Eighth-week US results can predict 12th-week results (right hip: sensitivity 100%, specificity 87.5%; left hip: sensitivity 100%, specificity 83.9%). In predicting 12th-week US results, 8th-week results are found to be more successful than 4th-week results.

Conclusions

Late diagnosis of DDH might cause serious public health problems. On the other hand, early US examinations can result in false-positive diagnosis. Unfortunately, there is still confusion about the optimal time for DDH screening with US, especially among radiologists who are not specialized in DDH sonography. A US scan performed at eighth week of life can predict any pathology presence safely and correctly.
Clinical Outcomes of Endoscopic Metal Stent Placement for Esophagojejunostomy Leakage After Total Gastrectomy for Gastric Adenocarcinoma
Authors: Lee Sung Ryol , Kim Hyung Ook , Park Jung Ho , Yoo Chang Hak
Published: March 2018

Objective:

Management of esophagojejunostomy leakage (EJL) has a high mortality rate and increases length of hospital stay. The aim of this study was to evaluate the feasibility of early postoperative gastroduodenoscopy and stent insertion to control EJL after total gastrectomy for gastric adenocarcinoma.

Patients and Methods:

Among 421 patients, 13 exhibited EJL. Of the 13 patients, 8 were treated with a covered self-expandable metal stent (SEMS) inserted by endoscopy and 5 patients were treated with surgery or conservative treatment.

Results:

The mortality rate was 0% in the SEMS-treated group. The median duration from primary surgery to discovery of leakage was 3.00 days overall [interquartile range (IQR), 2.00 to 5.50 d]. The time to enteral feeding after operation was 24.00 days (IQR, 18.00 to 31.00 d). Median postoperative hospital days was 35.0 days (IQR, 21.00 to 65.00 d). Median duration from leakage to gastroduodenoscopy was 7.00 days (IQR, 1.25 to 14.50 d). On endoscopic findings, most sizes of leakage site were 25% or smaller (8/9, 88.9%) within whole anastomosis size. Eight patients were treated by SEMS. No endoscopic procedure-related or leakage-related deaths occurred.

Conclusions:

The promising results for endoscopic treatment in this study showed that early endoscopic treatment using a covered SEMS for EJL might be a feasible, safe, and effective method in selected patients.
Pulse dynamics in reaction–diffusion equations with strong spatially localized impurities
Authors: Doelman Arjen , van Heijster Peter , Shen Jianhe
Published: March 2018

In this article, a general geometric singular perturbation framework is developed to study the impact of strong, spatially localized, nonlinear impurities on the existence, stability and bifurcations of localized structures in systems of linear reaction–diffusion equations. By taking advantage of the multiple-scale nature of the problem, we derive algebraic conditions determining the existence and stability of pinned single- and multi-pulse solutions. Our methods enable us to explicitly control the spectrum associated with a (multi-)pulse solution. In the scalar case, we show how eigenvalues may move in and out of the essential spectrum and that Hopf bifurcations cannot occur. By contrast, even a pinned 1-pulse solution can undergo a Hopf bifurcation in a two-component system of linear reaction–diffusion equations with (only) one impurity.

This article is part of the theme issue ‘Stability of nonlinear waves and patterns and related topics’.
Nonlinear modulation near the Lighthill instability threshold in 2+1 Whitham theory
Authors: Bridges Thomas J. , Ratliff Daniel J.
Published: March 2018

The dispersionless Whitham modulation equations in 2+1 (two space dimensions and time) are reviewed and the instabilities identified. The modulation theory is then reformulated, near the Lighthill instability threshold, with a slow phase, moving frame and different scalings. The resulting nonlinear phase modulation equation near the Lighthill surfaces is a geometric form of the 2+1 two-way Boussinesq equation. This equation is universal in the same sense as Whitham theory. Moreover, it is dispersive, and it has a wide range of interesting multi-periodic, quasi-periodic and multi-pulse localized solutions. For illustration the theory is applied to a complex nonlinear 2+1 Klein–Gordon equation which has two Lighthill surfaces in the manifold of periodic travelling waves.

This article is part of the theme issue ‘Stability of nonlinear waves and patterns and related topics’.
Partial differential systems with non-local nonlinearities: generation and solutions
Authors: Beck Margaret , Doikou Anastasia , Malham Simon J. A. , Stylianidis Ioannis
Published: March 2018

We develop a method for generating solutions to large classes of evolutionary partial differential systems with non-local nonlinearities. For arbitrary initial data, the solutions are generated from the corresponding linearized equations. The key is a Fredholm integral equation relating the linearized flow to an auxiliary linear flow. It is analogous to the Marchenko integral equation in integrable systems. We show explicitly how this can be achieved through several examples, including reaction–diffusion systems with non-local quadratic nonlinearities and the nonlinear Schrödinger equation with a non-local cubic nonlinearity. In each case, we demonstrate our approach with numerical simulations. We discuss the effectiveness of our approach and how it might be extended.

This article is part of the theme issue ‘Stability of nonlinear waves and patterns and related topics’.
The Tactile Receptive Fields of Freely Moving Caenorhabditis elegans Nematodes
Authors: Mazzochette E. A. , Nekimken A. L. , Loizeau F. , Whitworth J. , Huynh B. , Goodman M.B. , Pruitt B.L.
Published: March 2018

Sensory neurons embedded in skin are responsible for the sense of touch. In humans and other mammals, touch sensation depends on thousands of diverse somatosensory neurons. By contrast, Caenorhabditis elegans nematodes have six gentle touch receptor neurons linked to simple behaviors. The classical touch assay uses an eyebrow hair to stimulate freely moving C. elegans, evoking evasive behavioral responses. While this assay has led to the discovery of genes required for touch sensation, it does not provide control over stimulus strength or position. Here, we present an integrated system for performing automated, quantitative touch assays that circumvents these limitations and incorporates automated measurements of behavioral responses. Highly Automated Worm Kicker (HAWK) unites microfabricated silicon force sensors and video analysis with real-time force and position control. Using this system, we stimulated animals along the anterior-posterior axis and compared responses in wild-type and spc-1(dn) transgenic animals, which have a touch defect due to expression of a dominant-negative α spectrin protein fragment. As expected from prior studies, delivering large stimuli anterior to the mid-point of the body evoked a reversal, but such a stimulus applied posterior to the mid-point evoked a speed-up. The probability of evoking a response of either kind depended on stimulus strength and location; once initiated, the magnitude and quality of both reversal and speed-up behavioral responses were uncorrelated with stimulus location, strength, or the absence or presence of the spc-1(dn) transgene. Wild-type animals failed to respond when the stimulus was applied near the mid-point. These results establish that stimulus strength and location govern the activation of a stereotyped motor program and that the C. elegans body surface consists of two receptive fields separated by a gap.
Uncertainpy: A Python toolbox for uncertainty quantification and sensitivity analysis in computational neuroscience
Authors: Tennøe Simen , Halnes Geir , Einevoll Gaute T.
Published: March 2018

Computational models in neuroscience typically contain many parameters that are poorly constrained by experimental data. Uncertainty quantification and sensitivity analysis provide rigorous procedures to quantify how the model output depends on this parameter uncertainty. Unfortunately, the application of such methods is not yet standard within the field of neuroscience.

Here we present Uncertainpy, an open-source Python toolbox, tailored to perform uncertainty quantification and sensitivity analysis of neuroscience models. Uncertainpy aims to make it easy and quick to get started with uncertainty analysis, without any need for detailed prior knowledge. The toolbox allows uncertainty quantification and sensitivity analysis to be performed on already existing models without needing to modify the model equations or model implementation. Uncertainpy bases its analysis on polynomial chaos expansions, which are more efficient than the more standard Monte-Carlo based approaches.

Uncertainpy is tailored for neuroscience applications by its built-in capability for calculating characteristic features in the model output. The toolbox does not merely perform a point-to- point comparison of the “raw” model output (e.g. membrane voltage traces), but can also calculate the uncertainty and sensitivity of salient model response features such as spike timing, action potential width, mean interspike interval, and other features relevant for various neural and neural network models. Uncertainpy comes with several common models and features built in, and including custom models and new features is easy.

The aim of the current paper is to present Uncertainpy for the neuroscience community in a user- oriented manner. To demonstrate its broad applicability, we perform an uncertainty quantification and sensitivity analysis on three case studies relevant for neuroscience: the original Hodgkin-Huxley point-neuron model for action potential generation, a multi-compartmental model of a thalamic interneuron implemented in the NEURON simulator, and a sparsely connected recurrent network model implemented in the NEST simulator.

SIGNIFICANCE STATEMENT

A major challenge in computational neuroscience is to specify the often large number of parameters that define the neuron and neural network models. Many of these parameters have an inherent variability, and some may even be actively regulated and change with time. It is important to know how the uncertainty in model parameters affects the model predictions. To address this need we here present Uncertainpy, an open-source Python toolbox tailored to perform uncertainty quantification and sensitivity analysis of neuroscience models.
A giant amphipathic helix from a perilipin that is adapted for coating lipid droplets
Authors: Čopič Alenka , Antoine-Bally Sandra , Giménez-Andrés Manuel , Torre Garay César La , Antonny Bruno , Manni Marco M. , Pagnotta Sophie , Guihot Jeanne , Jackson Catherine L.
Published: March 2018

How proteins are targeted to lipid droplets (LDs) and distinguish the LD surface from the surfaces of other organelles is poorly understood, but many contain predicted amphipathic helices (AHs) that are involved in targeting. We have focused on human perilipin 4 (Plin4), which contains an AH that is exceptional in terms of length and repetitiveness. Using model cellular systems, we show that AH length, hydrophobicity, and charge are important for AH targeting to LDs and that these properties can compensate for one another, albeit at a loss of targeting specificity. Using synthetic lipids, we show that purified Plin4 AH binds poorly to lipid bilayers but strongly interacts with pure triglycerides, acting as a coat and forming small oil droplets. Because Plin4 overexpression alleviates LD instability under conditions where their coverage by phospholipids is limiting, we propose that the Plin4 AH replaces the LD lipid monolayer, for example during LD growth.
Disentangling genetically confounded polygenic associations between Attention-Deficit/Hyperactivity Disorder, literacy and language
Authors: Verhoef Ellen , Demontis Ditte , Burgess Stephen , Shapland Chin Yang , Dale Philip S. , Okbay Aysu , Neale Benjamin M. , Faraone Stephen V. ,   iPSYCH-Broad-PGC ADHD Consortium, Stergiakouli Evie , Smith George Davey , Fisher Simon E. , Børglum Anders D. , St Pourcain Beate
Published: March 2018

Interpreting polygenic overlap between ADHD and both literacy- and language-related impairments is challenging as genetic confounding can bias associations. Here, we investigate evidence for links between polygenic ADHD risk and multiple literacy- and language-related abilities (LRAs), assessed in UK children (N≤5,919), conditional on genetic effects shared with educational attainment (EA). Genome-wide summary statistics on clinical ADHD and years-of-schooling were obtained from large consortia (N≤326,041). ADHD-polygenic scores (ADHD-PGS) were inversely associated with LRAs in ALSPAC, most consistently with reading-related abilities, and explained ≤1.6% phenotypic variation. Polygenic links were then dissected into both genetic effects shared with and independent of EA using multivariable regressions (MVR), analogous to Mendelian Randomization approaches accounting for mediating effects. Conditional on EA, polygenic ADHD risk remained associated with multiple literacy-related skills, phonemic awareness and verbal intelligence, but not language-related skills such as listening comprehension and non-word repetition. Pooled reading performance showed the strongest overlap with ADHD independent of EA. Using conservative ADHD-instruments (P-threshold<5×10−8) this corresponded to a 0.35 decrease in Z-scores per log-odds in ADHD-liability (P=9.2×10−5). Using subthreshold ADHD-instruments (P-threshold<0.0015), these associations had lower magnitude, but higher predictive accuracy, with a 0.03 decrease in Z-scores (P=1.4×10−6). Polygenic ADHD-effects shared with EA were of equal strength and at least equal magnitude compared to those independent of EA, for all LRAs studied, and only detectable using subthreshold instruments. Thus, ADHD-related polygenic links are highly susceptible to genetic confounding, concealing an ADHD-specific association profile that primarily involves reading-related impairments, but few language-related problems.
Evolutionary inferences about quantitative traits are affected by underlying genealogical discordance
Authors: Mendes Fábio K. , Fuentes-González Jesualdo A. , Schraiber Joshua G. , Hahn Matthew W.
Published: March 2018

Modern phylogenetic methods used to study how traits evolve often require a single species tree as input, and do not take underlying gene tree discordance into account. Such approaches may lead to errors in phylogenetic inference because of hemiplasy — the process by which single changes on discordant trees appear to be homoplastic when analyzed on a fixed species tree. Hemiplasy has been shown to affect inferences about discrete traits, but it is still unclear whether complications arise when quantitative traits are analyzed. In order to address this question and to characterize the effect of hemiplasy on traits controlled by a large number of loci, we present a multispecies coalescent model for quantitative traits evolving along a species tree. We demonstrate theoretically and through simulations that hemiplasy decreases the expected covariances in trait values between more closely related species relative to the covariances between more distantly related species. This effect leads to an overestimation of a trait’s evolutionary rate parameter, to a decrease of the trait’s phylogenetic signal, and to increased false positive rates in comparative methods such as the phylogenetic ANOVA. We also show that hemiplasy affects discrete, threshold traits that have an underlying continuous liability, leading to false inferences of convergent evolution. The number of loci controlling a quantitative trait appears to be irrelevant to the trends reported, for all analyses. Our results demonstrate that gene tree discordance and hemiplasy are a problem for all types of traits, across a wide range of methods. Our analyses also point to the conditions under which hemiplasy is most likely to be a factor, and suggest future approaches that may mitigate its effects.
Voxel-wise T2 relaxometry of Normal Pediatric Brain Development in 326 healthy infants and toddlers
Authors: Fonov Vladimir S. , Leppert Ilana R. , Pike G. Bruce , Collins D. Louis ,   Brain Development Cooperative Group
Published: March 2018

Quantitative T2 data from an NIH-sponsored multi-center study of Normal Brain Development was used to perform automatic voxel-wise analysis of the changes in T2 evolution in the brain in healthy children within the age range from birth to 5 years. All data were non-linearly registered into a common coordinate space. The T2 parameters were estimated by 2 point fitting from the PD-weighted and T2-weighted image data, or by least-squares fitting of 4 data points when addition intermediate weighting images were available. The main result of this study is voxel-level map of monoexponential evolution of T2 in this age range indicating the delay (in months) and the rate (in 1/months) of development. The automatic maps are compared to manual region-of-interest based estimates of T2 evolution.
Enabling entrepreneurial behaviour in a land-based university
Authors: Manning Louise
Published: March 2018

Purpose

The purpose of this paper is to develop a conceptual framework along with a set of hypotheses that reflects the dynamic relationships that operate within an entrepreneurial land-based university in order to then undertake empirical research.

Design/methodology/approach

This paper, through reflection on existing literature, critiques the interactions between student, academic, educational institution and industry in order to conceptualise the entrepreneurial modus operandi of a land-based university.

Findings

Specialist universities, such as those that serve the land-based sector, need to demonstrate multiple excellences not only in terms of the education they provide for students, but also in terms of consistently meeting or exceeding government, research community, employers and societies expectations. An institutional framework must be in place to facilitate and enhance the quadruple interface of academic, institutional, industry and student entrepreneurial behaviour. The social and economic factors that mediate the dynamics within this framework first underpin student development supporting them to reach their potential, second inform teaching excellence and research practice and finally, lead to outcomes that contribute to the global, national and regional economy.

Originality/value

This paper is of value for those working in the educational sector as the model outlined can be used to critically reflect on current principles and practice and derive options for action to embed entrepreneurship more deeply within the organisational culture of a university.
A review of entrepreneurship education research
Authors: Henry Colette , Lewis Kate
Published: March 2018

Purpose

The purpose of this paper is to review recent published research on entrepreneurship education (EE) specifically within the special issue collections of the journal Education +Training, and to assess the overall contribution to the field. The research questions focus on: What topics are explored by these SI papers? What trends can be observed in relation to country context and methodological approach? How is EE defined in these papers, and how do the papers contribute to the wider entrepreneurship research agenda?

Design/methodology/approach

The paper uses an adapted version of the systematic literature review approach, focusing on the discrete special issues on entrepreneurship/enterprise education published in the journal Education + Training since 2010. A comprehensive reading guide was used to review the papers, with completed data compiled into a single excel spreadsheet to facilitate analysis. A total of 66 papers were reviewed.

Findings

A considerable range of themes, geographical contexts and methodological approaches were used in the papers reviewed. A mix of qualitative and quantitative approaches were also found. The papers were characterised by a strong international and applied dimension, with the core collective contribution of the SI papers laying in their direct relevance to practice.

Research limitations/implications

The paper is limited by its deliberate focus on a discrete set of special issue papers; however, the total of 66 papers included in the review is noteworthy.

Practical implications

The paper demonstrates the considerable learning that can be garnered from the Education + Training special issue collection for EE practitioners.

Originality/value

To the authors’ knowledge, this is the first time this discrete collection of special issue papers has been reviewed.
Towards a multi-level servitization framework
Authors: Lenka Sambit , Parida Vinit , Sjödin David Rönnberg , Wincent Joakim
Published: March 2018

Purpose

The dominant-view within servitization literature presupposes a progressive transition from product to service orientation. In reality, however, many manufacturing firms maintain both product and service orientations throughout their servitization journey. Using the theoretical lens of organizational ambivalence, the purpose of this paper is to explore the triggers, manifestation and consequences of these conflicting orientations.

Design/methodology/approach

A multiple case study method was used to analyze five large manufacturing firms that were engaged in servitization. Semi-structured interviews were conducted with 35 respondents across different functions within these firms.

Findings

Servitizing firms experience organizational ambivalence during servitization because of co-existing product and service orientations. This paper provides a framework that identifies the triggers of this ambivalence, its multi-level manifestation and its consequences. These provide implications for explaining why firms struggle to implement servitization strategies due to co-existing product and services orientations. Understanding organizational ambivalence, provides opportunity to manage related challenges and can be vital to successful servitization.

Originality/value

Considering the theoretical concept of ambivalence could advance the understanding of the effects and implications of conflicting orientations during servitization in manufacturing firms.
Six Sigma in healthcare: a systematic review of the literature
Authors: Antony Jiju , Palsuk Pruksathorn , Gupta Sandeep , Mishra Deepa , Barach Paul
Published: March 2018

Purpose

The purpose of this paper is to illustrate the systematic role played by Six Sigma methodology in improving the quality of healthcare. The literature review identifies the relevant opportunities for successful introduction and development of Six Sigma approach in healthcare sector.

Design/methodology/approach

A systematic methodology to identifying literature on Six Sigma in healthcare is presented. Web of Science, Medline, Emerald Insight, ASQ and ProQuest databases (1998-2016) were searched, and 68 papers of fair methodological quality were identified.

Findings

The findings of the systematic review reveal a growing interest in research on Six Sigma adoption in healthcare. The findings indicate that Six Sigma applications in healthcare have been focused on the entire hospital with no real focus on a particular department or function. The key findings on benefits, success factors, challenges and common tools of Six Sigma from the existing literature are also presented in the paper.

Research limitations/implications

The papers included in the systematic review were peer-reviewed papers available in English. Due to these limitations, relevant papers may have been excluded. Moreover, the authors have excluded all conference and white papers for their inclusion in this study.

Originality/value

This paper can serve as a guide on how Six Sigma approach can be applied to improve the quality of healthcare. The authors also believe that this is possibly the most comprehensive systematic literature review on the topic and will set the foundation for various research avenues based on the key findings of this study.
Understanding and detecting data fabrication in large-scale assessments
Authors: Yamamoto Kentaro , Lennon Mary Louise
Published: March 2018

Purpose

Fabricated data jeopardize the reliability of large-scale population surveys and reduce the comparability of such efforts by destroying the linkage between data and measurement constructs. Such data result in the loss of comparability across participating countries and, in the case of cyclical surveys, between past and present surveys. This paper aims to describe how data fabrication can be understood in the context of the complex processes involved in the collection, handling, submission and analysis of large-scale assessment data. The actors involved in those processes, and their possible motivations for data fabrication, are also elaborated.

Design/methodology/approach

Computer-based assessments produce new types of information that enable us to detect the possibility of data fabrication, and therefore the need for further investigation and analysis. The paper presents three examples that illustrate how data fabrication was identified and documented in the Programme for the International Assessment of Adult Competencies (PIAAC) and the Programme for International Student Assessment (PISA) and discusses the resulting remediation efforts.

Findings

For two countries that participated in the first round of PIAAC, the data showed a subset of interviewers who handled many more cases than others. In Case 1, the average proficiency for respondents in those interviewers’ caseloads was much higher than expected and included many duplicate response patterns. In Case 2, anomalous response patterns were identified. Case 3 presents findings based on data analyses for one PISA country, where results for human-coded responses were shown to be highly inflated compared to past results.

Originality/value

This paper shows how new sources of data, such as timing information collected in computer-based assessments, can be combined with other traditional sources to detect fabrication.
Conductorless singing group: a particular kind of self-managed team?
Authors: Page-Shipp Roy , Joseph Dawn , van Niekerk Caroline
Published: March 2018

Purpose

Coordination of group activity is rarely more important than in a singing group that has no designated conductor. This paper aims to explore the group dynamics in an 11-man singing group whose members, all over 60, have without exception occupied senior leadership positions in their working careers. The study arose because responses to a wider research study revealed interesting perceptions of leadership issues in the group.

Design/methodology/approach

All the members participated in semi-structured interviews and interpretative phenomenological analysis of the responses was used to process the responses. This enabled the identification of practices that support the group’s success and illustrated how this group of practiced “leaders” respond to a (relatively) conductorless situation.

Findings

It was confirmed that the group exhibits several characteristics of self-managed teams and string quartets. All members felt empowered to take a lead, although their backgrounds might have predisposed them to take such initiatives anyway. But the long-serving female accompanist is, by virtue inter alia of her superior musicianship, which appears to overcome any gender bias, in many respects the de facto leader. In performance, the singers synchronize their singing in response to cues from each other, but this could work better if given more specific attention.

Originality/value

Whereas conducted choirs have been extensively studied, such a self-managed group of amateur singers, all of whom are accustomed to leading in their working careers, has apparently not been studied. This study sheds some light on techniques for overcoming the challenges of creating quality performance in such a group and insights for similar groups, not necessarily musical, are identified.
Dryland soils in northern China sequester carbon during the early 2000s warming hiatus period
Authors: Kou Dan , Ma Wenhong , Ding Jinzhi , Zhang Beibei , Fang Kai , Hu Huifeng , Yu Jianchun , Wang Tian , Qin Shuqi , Zhao Xia , Fang Jingyun , Yang Yuanhe
Published: March 2018

Drylands, covering c. 45% of the Earth's terrestrial surface and supporting c. 38% of the global population, play a dominant role in the trend and interannual variability of global land carbon (C) sink. Given that a large proportion of organic C is stored in soils, our knowledge on soil C dynamics in drylands is crucial to evaluate terrestrial C‐climate feedback. However, credible understanding on this issue is still greatly limited by the lack of direct observations.

Here, based on a regional resampling of historical sites collected during 2002–2004, we explored the soil organic C (SOC) changes in various layers over the past decade across the arid/semi‐arid grasslands on the Inner Mongolian Plateau.

Our results revealed that the SOC density in this typical dryland increased significantly over the monitoring period, with a mean increase in 50.6 g C m−2 year−1 or 0.8% per year in the top 50 cm depth. Moreover, soil C dynamics exhibited contrasting spatial patterns between different layers: the rate of C accumulation in surface soils (0–10 cm) decreased, whereas that in deep soils (30–50 cm) exhibited an increasing trend along the aridity gradient.

Collectively, these findings demonstrate that dryland soils function as an important C sink, with the drier region tending to sequester C in deeper soils due to the greater root biomass allocation.

A plain language summary is available for this article.
Dark pigmentation limits thermal niche position in birds
Authors: Galván Ismael , Rodríguez‐Martínez Sol , Carrascal Luis M.
Published: March 2018

Animal pigmentation has evolved because of several adaptive functions. In the case of pigmentation produced by melanins, the most common pigments in animals, the main function is protection against UV radiation. However, pigmentation also affects animal surface's ability to absorb solar radiation and gain heat, which may represent a thermal constraint for endotherms due to their relatively high and constant body temperatures.

As darker colours absorb more radiation than lighter colours, dark‐pigmented endotherm animals may exhibit limited performance under high ambient temperatures and thus be constrained at occupying hot environments. While the influence of pigmentation on the determination of the thermal niches of ectotherms, particularly reptiles, has been the focus of several studies, this remains an unexplored issue for endotherm animals.

Here, we made a detailed quantification of the expression of pigmentation phenotypes produced by melanins in 96 species of birds inhabiting the Spanish sector of the Iberian Peninsula and estimated their climate niche position by calculating the effects of ambient temperature, insolation and precipitation on bird occurrence at a fine 10 × 10 km spatial scale.

After controlling for the body size and the nocturnal condition of species, and for phylogenetic and spatial effects, we found a positive association between plumage reflectance and the functional response of bird distribution to spring–summer ambient temperature and insolation but not to precipitation. Thus, bird species preferentially occupying the hotter and sunnier areas of Spain exhibit lighter plumage pigmentation.

Our findings suggest that darker birds are limited from occupying environments with high temperatures, unveiling a constraint in endotherms imposed by their pigmentation phenotype.

A plain language summary is available for this article.
Coordinated species importation policies are needed to reduce serious invasions globally: The case of alien bumblebees in South America
Authors: Aizen Marcelo A. , Smith‐Ramírez Cecilia , Morales Carolina L. , Vieli Lorena , Sáez Agustín , Barahona‐Segovia Rodrigo M. , Arbetman Marina P. , Montalva José , Garibaldi Lucas A. , Inouye David W. , Harder Lawrence D.
Published: March 2018

The global trade of species promotes diverse human activities but also facilitates the introduction of potentially invasive species into new environments. As species ignore national boundaries, unilateral national decisions concerning species trade set the stage for transnational species invasion with significant conservation, economic and political consequences.

The need for a coordinated approach to species importation policies is demonstrated by the introduction of two bumblebee species into Chile for crop pollination, despite Argentina banning commercial importation of alien bumblebees based on expert opinion. The large garden bumblebee, Bombus ruderatus, was first introduced in 1982, and the buff‐tailed bumblebee, Bombus terrestris, has been continually introduced since 1997 as part of the burgeoning bumblebee trade. Both species have subsequently invaded southern South America. Today, the consequences of the growth of the bumblebee trade for agricultural pollination ranks among the top 15 emerging environmental issues likely to affect global diversity.

Documented impacts of these invasions include the severe decline and local extinctions of the sole native Patagonian bumblebee, Bombus dahlbomii, pathogen transmission, flower damage and nectar robbing of native and cultivated plants.

Policy implications. The South American bumblebee invasions portrayed here should alert governments to the unintended consequences of the booming international bee trade. More broadly, this case demonstrates that one country's importation decisions can have policy implications for its neighbours without consultation. Regrettably, coordinated international measures to prevent species invasions are seldom considered in South America or elsewhere, despite existing legal frameworks. The bumblebee case and others provide stark evidence of the pressing need for coordinated specific and general international policies concerning global species trade and their implementation.
Native grass ground covers provide multiple ecosystem services in Californian vineyards
Authors: Daane Kent M. , Hogg Brian N. , Wilson Houston , Yokota Glenn Y.
Published: March 2018

Mechanisms responsible for the success or failure of agricultural diversification are often unknown. Most studies of arthropod pest management focus on enhancing natural enemy effectiveness. However, non‐crop plants can also change crop host quality by reducing or adding soil nutrients or water, and therefore improve or hamper pest suppression. Native perennial ground covers may provide food or habitat to natural enemies and, in terms of competition for soil nutrients or water, be more compatible with crop management than exotic annuals.

We conducted a 3‐year vineyard study to examine the impacts of native perennial grasses on pests, natural enemies, crop plant condition and soil properties. We included three ground cover treatments: bare soil with a grower standard drip irrigation; native grasses with drip irrigation; and native grasses with drip irrigation as well as an additional flood irrigation to keep the grasses green and growing during the season.

Numbers of leafhopper pests Erythroneura spp. decreased in both native grass treatments, where parasitism rates were higher. Vine petiole nitrate levels were lower in grass treatments, indicating competition for soil nitrogen, which is most often considered to be detrimental. Berry weight was higher in the irrigated treatment but did not differ between the bare soil and non‐irrigated grass treatment. Grape °Brix was similar in the bare soil and native grass treatments, suggesting native grasses did not compromise grape quality. In fact, leaf water stress was lower and soil moisture higher not only in the irrigated grass treatment but, at times, in the non‐irrigated grass treatment, compared with the bare soil treatment.

Synthesis and applications. Our work shows that native grasses contribute to a reduction in vineyard leafhopper pests by reducing host quality through competition for soil nitrogen and providing food resources and/or habitat for natural enemies. Native grasses also improve soil water content and may be part of a water conservation program for perennial crops in dry climate regions.
Vitamin B complex mitigates cardiac dysfunction in high‐methionine diet‐induced hyperhomocysteinemia
Authors: Jeremic Jovana , Nikolic Turnic Tamara , Zivkovic Vladimir , Jeremic Nevena , Milosavljevic Isidora , Srejovic Ivan , Obrenovic Radmila , Jancic Snezana , Rakocevic Milena , Matic Stevan , Djuric Dragan , Jakovljevic Vladimir
Published: March 2018

This research is designed to test the hypothesis that elevated homocysteine (Hcy) levels in vivo, caused by a deficit in vitamin B complex, promote changes in cardiac function and redox status that lead to heart failure. In order to conduct the study, we used adult male Wistar albino rats (n = 30; 4 weeks old; 100 ± 15 g body weight). Hyperhomocysteinaemia (HHcy) in these animals was achieved by dietary manipulation. For 4 weeks, the animals were fed with a standard rodent chow (control, CF), a diet enriched in methionine with no deficiency in B vitamins (i.e., folic acid, B6 and B12) (HMNV) or a diet enriched in methionine and deficient in B vitamins (HMLV). After 28 days of dietary manipulation, all animals were killed. The rat hearts were isolated and retrogradely perfused according to the Langendorff technique at a gradually increasing perfusion pressure. We found a negative correlation between elevated serum Hcy and total body and heart weight. The maximum rate of left ventricular pressure development was significantly increased in the HMNV group compared with in the other groups. Systolic left ventricular pressure was significantly changed in all groups. HHcy induces remodelling of the cardiac tissues, as moderate HHcy is associated with more prominent interstitial and perivascular fibrosis. Our results suggest that a high methionine diet without vitamin B complex causes profound negative effects associated with HHcy.
Informal social networks as generic contingency plans
Authors: Kirschenbaum Alan , Rapaport Carmit
Published: March 2018

Emergency contingency plans are conceived as an alternative rational‐logical set of actions when a formal emergency plan may be inadequate during an actual crisis. Most, like the official plan, are based on protocols inherent in the formal administrative structure of the organization with little attention paid to pervasive informal social networks found in the organization. We argue that a perspective focusing on informal social networks within organizations may provide a viable solution to supplement the formal plan. This approach integrates the power of informal social networks within and across organizations through the social context of transferring information and adaptive behaviours that have proven vital for organizational continuity. Special attention is paid to how a social network approach, as the basis for its integration into a viable contingency plan, is feasible for a variety of organizations.
Transferring biodiversity models for conservation: Opportunities and challenges
Authors: Sequeira Ana M. M. , Bouchet Phil J. , Yates Katherine L. , Mengersen Kerrie , Caley M. Julian
Published: March 2018

After decades of extensive surveying, knowledge of the global distribution of species still remains inadequate for many purposes. In the short to medium term, such knowledge is unlikely to improve greatly given the often prohibitive costs of surveying and the typically limited resources available.

By forecasting biodiversity patterns in time and space, predictive models can help fill critical knowledge gaps and prioritise research to support better conservation and management.

The ability of a model to predict biodiversity metrics in novel environments is termed “transferability,” and models with high transferability will be the most useful in this context.

Despite their potentially broad utility, little guidance exists on what confers high transferability to biodiversity models.

We synthesise recent advances in biodiversity model transfers to facilitate increased understanding of what underpins successful model transferability, demonstrating that a consistent approach has so far been lacking but is essential for achieving high levels of repeatability, transparency and accountability of model transfers.

We provide a set of guidelines to support efficient learning and the improvement of model transferability.
CD117‐ and vimentin‐positive telocytes in the bovine teat sphincter
Authors: Wagener M. G. , Leonhard‐Marek S. , Häger J.‐D. , Pfarrer C.
Published: March 2018

Mastitis is a common economically relevant problem in dairy farming. As the major entry for pathogens is the papillary duct, one of the first defence mechanisms is the teat sphincter. This sphincter shows a rhythmic contractility of yet unknown origin. Searching for possible modulatory pacemaker cells, teat sphincters of eight cows were stained immunohistochemically with antibodies against CD117 and vimentin and evaluated microscopically for the presence of telocytes. CD117‐ and vimentin‐positive telocytes with telopodes were found in close contact with smooth muscle cells. Our findings present a first evidence of telocytes in the teat of bovines.
Identification of African antelope species: Using thermographic videos to test the efficacy of real‐time thermography
Authors: Goodenough Anne E. , Carpenter William S. , MacTavish Lynne , Theron Charles , Delbridge Matthew , Hart Adam G.
Published: March 2018

Real‐time thermography using the live‐view function of a thermal camera has considerable potential to improve surveys of nocturnal wildlife relative to traditional spotlighting, while also decreasing disturbance. However, ability to identify species accurately is paramount. We use video as a proxy for real‐time thermography to test African antelope identification accuracy among 34 observers of differing experience. Overall accuracy was 41% but there were substantial species‐specific differences (e.g. wildebeest (Connochaetes taurinus) = 81%; reedbuck (Redunca arundinum) = 12%). Observer experience was significantly positively related to accuracy (inexperienced = 30%; expert = 61%) with experienced observers being better able to use subtle movement and behavioural information to identify animals. However, the effect of experience was inconsistent between species: even experts found some species challenging (e.g. waterbuck (Kobus ellipsiprymnus) where coat patterning was invisible thermographically). Self‐assessed confidence did not correlate with accuracy. Observers who were good at identifying species were also good at assessing group size. We conclude that real‐time thermography is not a “magic bullet” and the understanding of species‐specific effectiveness is vital. However, for some species and some groups of observers, accuracy can be extremely high (e.g. 100% for expert observers viewing wildebeest). Tailored training is essential for real‐time thermography to be a reliable field technique.
Preclinical In Vitro Safety Investigations of Submicron Sized Hemoglobin Based Oxygen Carrier HbMP‐700
Authors: Kao Ijad , Xiong Yu , Steffen Axel , Smuda Kathrin , Zhao Lian , Georgieva Radostina , Pruss Axel , Bäumler Hans
Published: March 2018

Hemoglobin‐based oxygen carriers (HBOCs) are being developed as oxygen and plasma volume‐expanding therapeutics though their potential to promote oxidative tissue injury and nitric oxide (NO) scavenging combined with vasoconstriction has raised safety concerns. Therefore, we focused on these aspects during preclinical studies performed with the recently introduced hemoglobin microparticles (HbMP‐700). Besides oxidative stress, we investigated possible vasoconstrictory influence of HBOCs as well as genetic toxicity. The novel developed HbMP‐700 presented here provides a high oxygen affinity which prevents premature oxygen oversupply and avoids vasoconstriction of small blood vessels in vitro. The size of these particles is 700 nm (larger than 100 nm and smaller than 1000 nm) in order to prevent penetration through the blood vessel's endothelial gaps, NO‐scavenging, and to avoid phagocytosis of large particles. We expect that the HbMP‐700 meets the sophisticated requirements as a universal blood substitute.
Mechanical and Chemical Predifferentiation of Mesenchymal Stem Cells Into Cardiomyocytes and Their Effectiveness on Acute Myocardial Infarction
Authors: Abd Emami Baharak , Mahmoudi Elena , Shokrgozar Mohammad Ali , Dehghan Mohammad Mehdi , Farzad Mohajeri Saeed , Haghighipour Nooshin , Marjanmehr Seyyed Hossein , Molazem Mohammad , Amin Susan , Gholami Hossein
Published: March 2018

Myocardial infarction is one of the leading causes of death all over the world. Mesenchymal stem cells (MSCs) transplantation has shown a promising potential to recovery of ischemic heart disease due to their capability in differentiating into cardiac cells. However, various investigations have been performed to optimize the efficacy of cardiac cell therapy in recent years. Here, we sought to interrogate the effect of autologous transplantation of undifferentiated and predifferentiated adipose and bone marrow‐derived MSCs in a rabbit model of myocardial infarction and also to investigate whether cardiac function could be improved by mechanically induced MSCs via equiaxial cyclic strain. The two sources of MSCs were induced toward cardiomyocyte phenotype using mechanical loading and chemical factors and thereafter injected into the infarcted myocardium of 35 rabbits. Echocardiography and histopathology studies were used to evaluate cardiac function after 2 months. The results demonstrated significant scar size reduction and greater recovery of left ventricle ejection fraction after transplantation of predifferentiated cells, though the differences were not significant when comparing mechanically with chemically predifferentiated MSCs. Thus, although there was no significant improvement in infarcted myocardium between chemically and mechanically predifferentiated MSCs, mechanically induced cells are more preferred due to lack of any chemical intervention and cost reasonableness in their preparation method. Outcomes of this study may be useful for developing future therapeutic strategies, however long‐term assessments are still required to further examine their effectiveness.