bluuebunny/crossref_metadata_2025 huggingface dataset:
Electron Emission Cross Sections for Collisions of Dressed Ions with Atomic and Molecular Targets
Authors: Toburen L.H. , DuBois R.D.
Published: February 2017

As ions pass through matter at sufficiently low impact energies, less than a few hundred keV.u-1, electrons are captured by the ion. Subsequent collisions can remove these, or other, projectile electrons from the ion. Although the actual energy lost by the projectile during charge changing collisions may be quite small, captured electrons may have a profound affect on the ionisation efficiency of the moving particle. For distant collisions involving high energy ions, the primary effect of bound projectile electrons is to screen the projectile nuclear charge and therby reduce the probability for energy loss. As the ion slows to below a few hundred keV.u-1, however, rather than simply screen the projectile nuclear charge, the 'incident' bound electrons tend to contribute to the target ionisation and the probability for target ionisation may actually be enhanced with respect to that expected for an incident fully stripped ion. This can be particularly important for neutral particle impact because of the larger number of bound electrons involved. Studies with hydrogen, helium and carbon ions and neutrals show that the cross sections for ejection of low-energy electrons (1-20 eV) by neutral atoms is comparable to, or greater than, those for equal velocity proton impact and that the cross sections for ejecting fast electrons (binary encounter electrons) are also increased by the presence of bound projectile electrons.
Electret Dosemeters for Tritium Beta Rays
Authors: Miki T. , Ikeya M. , Matsuyama M. , Watanabe K.
Published: February 2017

The decrease of the electret charge by exposure to gaseous tritium was studied in order to develop an electret personnel dosemeter for tritium. The electret charge decreases in proportion to the product of the tritium activity and the exposure time, corresponding to the theoretical response of electret dosemeters in the ionisation chamber mode. The sensitivity is high enough to be of practical use. Several outstanding problems, especially the compensation of the contribution from atmospheric radon to the electret charge reduction, are discussed. A hybrid type electret dosemeter is proposed to compensate for the contribution of atmospheric radon and background gamma rays.
Larval antlions with more pronounced behavioural asymmetry show enhanced cognitive skills
Authors: Miler Krzysztof , Kuszewska Karolina , Woyciechowski Michał
Published: February 2017

Brain lateralization is hypothesized to improve the efficiency of information processing. Here, we found that some
Myrmeleon bore
antlion larvae showed individual asymmetry in righting from a supine to normal position over one side of their body, which can be considered a reflection of greater brain lateralization. We demonstrated that these behaviourally asymmetrical individuals showed improved learning abilities, providing novel evidence that brain lateralization leads to beneficial effects on cognitive functions.
Variation in wall shear stress in channel networks of zebrafish models
Authors: Choi Woorak , Kim Hye Mi , Park Sungho , Yeom Eunseop , Doh Junsang , Lee Sang Joon
Published: February 2017

Physiological functions of vascular endothelial cells (ECs) vary depending on wall shear stress (WSS) magnitude, and the functional change affects the pathologies of various cardiovascular systems. Severalin vitroandin vivomodels have been used to investigate the functions of ECs under different WSS conditions. However, these models have technical limitations in precisely mimicking the physiological environments of ECs and monitoring temporal variations of ECs in detail. Although zebrafish (Danio rerio) has several strategies to overcome these technical limitations, zebrafish cannot be used as a perfect animal model because applying various WSS conditions on blood vessels of zebrafish is difficult. This study proposes a new zebrafish model in which various WSS can be applied to the caudal vein. The WSS magnitude is controlled by blocking some parts of blood-vessel networks. The accuracy and reproducibility of the proposed method are validated using an equivalent circuit model of blood vessels in zebrafish. The proposed method is applied to lipopolysaccharide (LPS)-stimulated zebrafish as a typical application. The proposed zebrafish model can be used as anin vivoanimal model to investigate the relationship between WSS and EC physiology or WSS-induced cardiovascular diseases.
Spatial distribution and characterization of non-apical progenitors in the zebrafish embryo central nervous system
Authors: McIntosh Rebecca , Norris Joseph , Clarke Jon D. , Alexandre Paula
Published: February 2017

Studies of non-apical progenitors (NAPs) have been largely limited to the developing mammalian cortex. They are postulated to generate the increase in neuron numbers that underlie mammalian brain expansion. Recently, NAPs have also been reported in the retina and central nervous system of non-mammalian species; in the latter, however, they remain poorly characterized. Here, we characterize NAP location along the zebrafish central nervous system during embryonic development, and determine their cellular and molecular characteristics and renewal capacity. We identified a small population of NAPs in the spinal cord, hindbrain and telencephalon of zebrafish embryos. Live-imaging analysis revealed at least two types of mitotic behaviour in the telencephalon: one NAP subtype retains the apical attachment during division, while another divides in a subapical position disconnected from the apical surface. All NAPs observed in spinal cord lost apical contact prior to mitoses. These NAPs express HuC and produce two neurons from a single division. Manipulation of Notch activity reveals that neurons and NAPs in the spinal cord use similar regulatory mechanisms. This work suggests that the majority of spinal NAPs in zebrafish share characteristics with basal progenitors in mammalian brains.
Genetic and life-history consequences of extreme climate events
Authors: Vincenzi Simone , Mangel Marc , Jesensek Dusan , Garza John Carlos , Crivelli Alain J.
Published: February 2017

Climate change is predicted to increase the frequency and intensity of extreme climate events. Tests on empirical data of theory-based predictions on the consequences of extreme climate events are thus necessary to understand the adaptive potential of species and the overarching risks associated with all aspects of climate change. We tested predictions on the genetic and life-history consequences of extreme climate events in two populations of marble trout
Salmo marmoratus
that have experienced severe demographic bottlenecks due to flash floods. We combined long-term field and genotyping data with pedigree reconstruction in a theory-based framework. Our results show that after flash floods, reproduction occurred at a younger age in one population. In both populations, we found the highest reproductive variance in the first cohort born after the floods due to a combination of fewer parents and higher early survival of offspring. A small number of parents allowed for demographic recovery after the floods, but the genetic bottleneck further reduced genetic diversity in both populations. Our results also elucidate some of the mechanisms responsible for a greater prevalence of faster life histories after the extreme event.
Distinct contributions by frontal and parietal cortices support working memory
Authors: Mackey Wayne E. , Curtis Clayton E.
Published: February 2017

Although subregions of frontal and parietal cortex both contribute and coordinate to support working memory (WM) functions, their distinct contributions remain elusive. Here, we demonstrate that perturbations to topographically organized human frontal and parietal cortex during WM maintenance cause distinct but systematic distortions in WM. The nature of these distortions supports theories positing that parietal cortex mainly codes for retrospective sensory information, while frontal cortex codes for prospective action.

Acknowledgements

The US National Institutes of Health (R01 EY016407 to C.E.C.) and the National Science Foundation (Graduate Research Fellowship Program to W.E.M.) supported the research.

Author Contributions

W.E.M and C.E.C. designed the experiment, collected and analyzed the data, and wrote the manuscript.

Conflict of interest:

The authors declare no competing financial interests.
Boredom begets creativity: a solution to the exploitation-exploration trade-off in predictive coding
Authors: Gomez-Ramirez Jaime , Costa Tommaso
Published: February 2017

Here, we investigate whether systems that minimize prediction error e.g. predictive coding, can also show creativity, or on the contrary, prediction error minimization unqualifies for the design of systems that respond in creative ways to non recurrent problems. We argue that there is a key ingredient that has been overlooked by researchers that needs to be incorporated to understand intelligent behavior in biological and technical systems. This ingredient is boredom. We propose a mathematical model based on the Black-Scholes-Merton equation which provides mechanistic insights into the interplay between boredom and prediction pleasure as the key drivers of behavior.
Integrative Deep Models for Alternative Splicing
Authors: Jha Anupama , Gazzara Matthew R. , Barash Yoseph
Published: February 2017

Advancements in sequencing technologies have highlighted the role of alternative splicing (AS) in increasing transcriptome complexity. This role of AS, combined with the relation of aberrant splicing to malignant states, motivated two streams of research, experimental and computational. The First involves a myriad of techniques such as RNA-Seq and CLIP-Seq to identify splicing regulators and their putative targets. The second involves probabilistic models, also known as splicing codes, which infer regulatory mechanisms and predict splicing outcome directly from genomic sequence. To date, these models have utilized only expression data. In this work we address two related challenges: Can we improve on previous models for AS outcome prediction and can we integrate additional sources of data to improve predictions for AS regulatory factors. We perform a detailed comparison of two previous modeling approaches, Bayesian and Deep Neural networks, dissecting the confounding effects of datasets and target functions. We then develop a new target function for AS prediction and show that it significantly improves model accuracy. Next, we develop a modeling framework to incorporate CLIP-Seq, knockdown and over-expression experiments, which are inherently noisy and suffer from missing values. Using several datasets involving key splice factors in mouse brain, muscle and heart we demonstrate both the prediction improvements and biological insights offered by our new models. Overall, the framework we propose offers a scalable integrative solution to improve splicing code modeling as vast amounts of relevant genomic data become available.

Availability:code and data will be available on Github following publication.
Prion Transfection of Yeast
Authors: Edskes Herman K. , Kryndushkin Dmitry , Shewmaker Frank , Wickner Reed B.
Published: February 2017

Transfection of yeast with amyloid filaments, made from recombinant protein or prepared from extracts of cells infected with a prion, has become an important method in characterizing yeast prions. Here, we describe a method for transmission of [URE3] with Ure2p amyloid that is based on a previously published protocol for transfection with Sup35p filaments to make cells [PSI+]. This method may be used for other prions by changing just the amyloid source, host strain, and plating medium.
Preparation of Protein Extracts from Schizosaccharomyces pombe Using Trichloroacetic Acid Precipitation
Authors: Grallert Agnes , Hagan Iain M.
Published: February 2017

Schizosaccharomyces pombe is an attractive model organism with which to study core principles of conserved molecular cell biology processes. The ability to monitor protein behavior following separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) underpins much of this activity. Here we describe a robust protocol for the preparation of protein samples for analysis by SDS-PAGE.
Mapping Short Sequence Reads to a Reference Genome
Authors: Hung Jui-Hung , Weng Zhiping
Published: February 2017

This protocol describes mapping short sequence reads to a reference genome using several programs. The example in this protocol starts with a ChIP-seq data set in FASTQ format, aligns the reads to the human genome using Bowtie, and uses some useful utilities of SAMtools and BEDTools. SAMtools and BEDTools are two collections of executables for manipulating the results of short-read aligners. By combining these tools, one can summarize and visualize alignments produced by Bowtie and perform basic analysis, such as determining the number of reads that are mapped to a certain gene. These tools can also be easily incorporated into computational pipelines of more complex analyses.
Preparation of Slice Cultures from Rodent Hippocampus
Authors: Gee Christine E. , Ohmert Iris , Wiegert J. Simon , Oertner Thomas G.
Published: February 2017

This protocol describes the preparation of hippocampal slice cultures from rat or mouse pups using sterile conditions that do not require the use of antibiotics or antimycotics. Combining very good optical and electrophysiological accessibility with a lifetime approaching that of the intact animal, many fundamental questions about synaptic plasticity and long-term dynamics of network connectivity can be addressed with this preparation.
Keep it together: restraints in crystallographic refinement of macromolecule–ligand complexes
Authors: Steiner Roberto A. , Tucker Julie A.
Published: February 2017

A short introduction is provided to the concept of restraints in macromolecular crystallographic refinement. A typical ligand restraint-generation process is then described, covering types of input, the methodology and the mechanics behind the software in general terms, how this has evolved over recent years and what to look for in the output. Finally, the currently available restraint-generation software is compared, concluding with some thoughts for the future.
An investigation into the investment decision-making practices of South African institutional investors
Authors: Nsibande Mduduzi , Boshoff Douw Gert Brand
Published: February 2017

Purpose

The South African listed property market has changed its legal basis from property loan stock companies and property unit trusts to adopt the more familiar international structure, real estate investment trusts. The main distinction is how shareholding is structured and investment returns are paid out to shareholders, which results in a different tax treatment. It is hoped that this change would attract more foreign investment, but it is questionable if this is sufficient to convince global investors who, amidst a seeming worsening of the stability in the political and economic environment, would probably need more insight into aspects such as investment decision making within these South African organisations. The paper aims to discuss these issues.

Design/methodology/approach

Using a balanced scorecard (BSC) framework, this study investigates the relevance of investment decision-making frameworks in South Africa. A survey using a sample of institutional investors that are included in the South African Property Market Index was conducted.

Findings

The study found similarities in decision-making priorities of South African institutional investors to those of previous studies. With the focus on retail property, tenant mix and secondary to that, quality of the centre management team is found to be important for forecasting expected returns in a retail investment decision environment. Diversification strategies were found to have similar results to previous studies, leaning more towards geographic location than economic location. Further, the study suggested the use of a BSC framework, linking the financial information and different financial ratios to nonfinancial aspects that need specific consideration in a retail investment environment.

Research limitations/implications

Retail property is considered to be of particular concern due to the business enterprise value that could be created if superior management techniques are applied. The investment decision stage concerned with forecasting expected returns relies on financial and quantitative models such as those derived from Modern Portfolio Theory. In a shopping mall environment, however, future performance is driven by nonfinancial factors, for example, tenant mix and superior customer experience. Therefore, forecasting expected returns in a retail environment requires a nuanced approach relative to other commercial property sectors.

Originality/value

The paper is considered to be original in its analysis of the retail real estate market in South Africa. This offers new insight into retail properties specifically, but also how investors in South Africa react to decision-making practices. This adds value in the internationalisation of the property market and the consistency and transparent practices applied globally.
Visualizing Digital Forensic Datasets: A Proof of Concept
Authors: Tassone Christopher F.R. , Martini Ben , Choo Kim‐Kwang Raymond
Published: February 2017

Digital forensic visualization is an understudied area despite its potential to achieve significant improvements in the efficiency of an investigation, criminal or civil. In this study, a three‐stage forensic data storage and visualization life cycle is presented. The first stage is the decoding of data, which involves preparing both structured and unstructured data for storage. In the storage stage, data are stored within our proposed database schema designed for ensuring data integrity and speed of storage and retrieval. The final stage is the visualization of stored data in a manner that facilitates user interaction. These functionalities are implemented in a proof of concept to demonstrate the utility of the proposed life cycle. The proof of concept demonstrates the utility of the proposed approach for the storage and visualization of digital forensic data.
A systematic review of sex and age factors in neuroleptic malignant syndrome diagnosis frequency
Authors: Gurrera Ronald J.
Published: February 2017

Objective

To examine sex and age distributions in neuroleptic malignant syndrome (NMS) patients based on a systematic literature review.

Method

EMBASE and PubMed databases were searched to identify any observation of NMS published from January 1, 1998 through November 1, 2014 that was accessible and interpretable (using language translation software). Redundant and equivocal reports were excluded. Sex ratio and age distributions were examined using standard graphical techniques and measures of association.

Results

Twenty‐eight independent sex ratio estimates were included. Males predominated in most (75%) estimates with an overall median sex ratio of 1.47 (95% CI, 1.20–1.80). NMS incidence peaked at age 20–25 years and declined steadily thereafter, with males consistently outnumbering females at all but the oldest age intervals.

Conclusion

NMS patients are 50% more likely to be males, and NMS is most likely to occur in young adulthood.
Spatial Models of Legislative Effectiveness
Authors: Hitt Matthew P. , Volden Craig , Wiseman Alan E.
Published: February 2017

Spatial models of policymaking have evolved from the median voter theorem to the inclusion of institutional considerations such as committees, political parties, and various voting and amendment rules. Such models, however, implicitly assume that no policy is better than another at solving public policy problems and that all policy makers are equally effective at advancing proposals. We relax these assumptions, allowing some legislators to be more effective than others at creating high‐quality proposals. The resulting Legislative Effectiveness Model (LEM) offers three main benefits. First, it can better account for policy changes based on the quality of the status quo, changing our understanding of how to overcome gridlock in polarized legislatures. Second, it generalizes canonical models of legislative politics, such as median voter, setter, and pivotal politics models, all of which emerge as special cases within the LEM. Third, the LEM offers significant new empirical predictions, some of which we test (and find support for) within the U.S. Congress.
The CYP3A biomarker 4β‐hydroxycholesterol does not improve tacrolimus dose predictions early after kidney transplantation
Authors: Størset Elisabet , Hole Kristine , Midtvedt Karsten , Bergan Stein , Molden Espen , Åsberg Anders
Published: February 2017

Aims

Tacrolimus is a cornerstone in modern immunosuppressive therapy after kidney transplantation. Tacrolimus dosing is challenged by considerable pharmacokinetic variability, both between patients and over time after transplantation, partly due to variability in cytochrome P450 3A (CYP3A) activity. The aim of this study was to assess the value of the endogenous CYP3A marker 4β‐hydroxycholesterol (4βOHC) for tacrolimus dose individualization early after kidney transplantation.

Methods

Data were obtained from 79 adult kidney transplant recipients who contributed a total of 625 4βOHC measurements and 1999 tacrolimus whole blood concentrations during the first 2 months after transplantation. The relationships between 4βOHC levels and individual estimates of tacrolimus apparent plasma clearance (CL/Fplasma) at different time points after transplantation were investigated using scatterplots and population pharmacokinetic modelling.

Results

There was no significant correlation between pre‐transplant 4βOHC levels and tacrolimus CL/Fplasma the first week (r = 0.19 [95% CI −0.03‐0.40]) or between 4βOHC and tacrolimus CL/Fplasma 1 week (r = 0.20 [−0.11‐0.47]), 4 weeks (r = 0.21 [−0.07‐0.46]) or 2 months (r = 0.24 [−0.03‐0.48]) after transplantation (P ≥ 0.06). In the population analysis, time‐varying 4βOHC was not a statistically significant covariate on tacrolimus CL/Fplasma, neither in terms of absolute values (P = 0.11) nor in terms of changes from baseline (P = 0.17). 4βOHC values increased between 1 week and 2 months after transplantation (median change +57% [IQR +22–83%], P < 0.001), indicating increasing CYP3A activity. Contradictorily, tacrolimus CL/Fplasma decreased over the same period (median change −13% [IQR −3 to −26%], P < 0.001).

Conclusions

4βOHC does not appear to have a clinical potential to improve individualization of tacrolimus doses early after kidney transplantation.
Using the SIRDE model of social change to examine the vote of Scottish teenagers in the 2014 independence referendum
Authors: Grant Peter R. , Bennett Mark , Abrams Dominic
Published: February 2017

Five hundred and seventy‐three Scottish high school students were surveyed in the 2 months following the 2014 referendum on Scotland's independence. We used the Social Identity, Relative Deprivation, collective Efficacy (SIRDE) model of social change to examine the social psychological factors that should have influenced the voting choices of these teenagers. Structural equation modelling indicated that the SIRDE model fit the data and largely supported four sets of hypotheses derived from the model. Specifically, (1) those with a stronger Scottish identity, (2) those who felt frustrated and angry that Scottish people are discriminated against in British society, and (3) those who believed that Scottish people are not able to improve their relatively poor social conditions within the United Kingdom (a lack of collective efficacy) were more likely to hold separatist beliefs. Further, the relationships between identity, relative deprivation, and collective efficacy, on the one hand, and voting for Scotland's independence, on the other, were fully mediated by separatist social change beliefs. Consistent with the specificity of the model, neither political engagement nor personal relative deprivation were associated with voting choice, whereas the latter was associated with lower life satisfaction. The implications and limitations of these findings are discussed.
Quantitative Linguistic Predictors of Infants’ Learning of Specific English Words
Authors: Swingley Daniel , Humphrey Colman
Published: February 2017

To evaluate which features of spoken language aid infant word learning, a corpus of infant‐directed speech (M. R. Brent & J. M. Siskind, 2001) was characterized on several linguistic dimensions and statistically related to the infants’ vocabulary outcomes word by word. Comprehension (at 12 and 15 months) and production (15 months) were predicted by frequency, frequency of occurrence in one‐word utterances, concreteness, utterance length, and typical duration. These features have been proposed to influence learning before, but here their relative contributions were measured. Mothers’ data predicted learning in their own children better than in other children; thus, vocabulary is measurably aligned within families. These analyses provide a quantitative basis for claims concerning the relevance of several properties of maternal English speech in facilitating early word learning.
Fluoride in the diet of 2‐years‐old children
Authors: Martinez‐Mier E. A. , Spencer Kathryn L. , Sanders Brian J. , Jones James E. , Soto‐Rojas Armando E. , Tomlin Angela M. , Vinson LaQuia A. , Weddell James. A. , Eckert George J.
Published: February 2017

Objectives

This study aimed to calculate the fluoride concentrations of commonly consumed foods and beverages for 2‐years‐old children utilizing market basket information for the US Midwest region.

Methods

Total Diet Study food lists were cross‐referenced with National Health and Nutrition Examination Survey—What We Eat in America data to determine the foods and beverages to be included. Fluoride concentrations were determined using a modification of the hexamethyldisiloxane microdiffusion technique. Fluoride concentrations were summarized for each of the food categories. Daily dietary fluoride intake was estimated using a simulation analysis.

Results

Food and beverage fluoride concentrations varied widely, ranging from nondetectable for some oils and dairy products to more than 3.0 μgF/g food for some processed meats, fish and fruits. The estimated mean (±SD) daily dietary fluoride intake, excluding dentifrice and supplements, was 412±114 μgF/d. The estimated average ingestion for a 2‐years‐old weighing 12.24 kg was 0.034±0.009 mg/kg/d. A diet based on foods and beverages in the fifth percentile of fluoride intake distribution for an average child would result in 247 μgF/d or 0.020 mg/kg/d, while a diet with foods and beverages in the 95th percentile would result in a total intake of 622 μgF/d or 0.051 mg/kg/d.

Conclusions

The fluoride concentrations of foods and beverages vary widely, and, if items in the 95th percentile of fluoride intake distribution are ingested, children could consume more fluoride than the recommended 0.05 mg/kg/d. Fluoride intake calculated in this study was higher than historically reported dietary levels.
Explant culture: An advantageous method for isolation of mesenchymal stem cells from human tissues
Authors: Hendijani Fatemeh
Published: February 2017

Mesenchymal stem cell (MSC) research progressively moves towards clinical phases. Accordingly, a wide range of different procedures were presented in the literature for MSC isolation from human tissues; however, there is not yet any close focus on the details to offer precise information for best method selection. Choosing a proper isolation method is a critical step in obtaining cells with optimal quality and yield in companion with clinical and economical considerations. In this concern, current review widely discusses advantages of omitting proteolysis step in isolation process and presence of tissue pieces in primary culture of MSCs, including removal of lytic stress on cells, reduction of in vivo to in vitro transition stress for migrated/isolated cells, reduction of price, processing time and labour, removal of viral contamination risk, and addition of supporting functions of extracellular matrix and released growth factors from tissue explant. In next sections, it provides an overall report of technical highlights and molecular events of explant culture method for isolation of MSCs from human tissues including adipose tissue, bone marrow, dental pulp, hair follicle, cornea, umbilical cord and placenta. Focusing on informative collection of molecular and methodological data about explant methods can make it easy for researchers to choose an optimal method for their experiments/clinical studies and also stimulate them to investigate and optimize more efficient procedures according to clinical and economical benefits.
Analysis of gene expression profiles between apical papilla tissues, stem cells from apical papilla and cell sheet to identify the key modulators in MSCs niche
Authors: Diao Shu , Lin Xiao , Wang Liping , Dong Rui , Du Juan , Yang Dongmei , Fan Zhipeng
Published: February 2017

Objectives

The microenvironmental niche plays the key role for maintaining the cell functions. The stem cells from apical papilla (SCAPs) are important for tooth development and regeneration. However, there is limited knowledge about the key factors in niche for maintaining the function of SCAPs. In this study, we analyse the gene expression profiles between apical papilla tissues, SCAPs and SCAPs cell sheet to identify the key genes in SCAPs niche.

Materials and methods

Microarray assays and bioinformatic analysis were performed to screen the differential genes between apical papilla tissues and SCAPs, and SCAPs and SCAPs cell sheet. Recombinant human BMP6 protein was used in SCAPs. Then CCK‐8 assay, CFSE assay, alkaline phosphatase activity, alizarin red staining, quantitative calcium analysis and real‐time reverse transcriptase‐polymerase chain reaction were performed to investigate the cell proliferation and differentiation potentials of SCAPs.

Results

Microarray analysis found that 846 genes were up‐regulated and 1203 genes were down‐regulated in SCAPs compared with apical papilla tissues. While 240 genes were up‐regulated and 50 genes were down‐regulated in SCAPs compared to in SCAPs cell sheet. Moreover, only 31 gene expressions in apical papilla tissues were recovered in cell sheet compared with SCAPs. Bioinformatic analysis identified that TGF‐β, WNT and MAPK signalling pathways may play an important role in SCAPs niche. Based on the analysis, we identified one key growth factor in niche, BMP6, which could enhance the cell proliferation, the osteo/dentinogenic, neurogenic and angiogenic differentiation potentials of SCAPs.

Conclusions

Our results provided insight into the mechanisms of the microenvironmental niche which regulate the function of SCAPs, and identified the key candidate genes in niche to promote mesenchymal stem cells‐mediated dental tissue regeneration.
Fatigue crack closure: a review of the physical phenomena
Authors: Pippan R. , Hohenwarter A.
Published: February 2017

Plasticity‐induced, roughness‐induced and oxide‐induced crack closures are reviewed. Special attention is devoted to the physical origin, the consequences for the experimental determination and the prediction of the effective crack driving force for fatigue crack propagation. Plasticity‐induced crack closure under plane stress and plane strain conditions require, in principle, a different explanation; however, both types are predictable. This is even the case in the transition region from the plane strain to the plane stress state and all types of loading conditions including constant and variable amplitude loading, the short crack case or the transition from small‐scale to large‐scale yielding. In contrast, the prediction of roughness‐induced and oxide‐induced closures is not as straightforward.
An analytical expression for the J2‐integral of an interfacial crack in orthotropic bimaterials
Authors: Tafreshi A.
Published: February 2017

This paper presents a new analytical expression relating the J2‐integral and stress intensity factors (SIF) in an in‐plane traction‐free crack between two orthotropic elastic solids using the complex function method. The singular oscillatory near tip field of a bimaterial interfacial crack is usually characterized by a pair of SIFs. In linear elastic interfacial fracture mechanics, the majority of numerical and experimental methods rely on the analytical equations relating Jk‐integrals and SIFs. Although an analytical equation relating J1‐integral or strain energy release rate and SIFs is available, a similar relation for J2‐integral in debonded anisotropic solids is non‐existent. Using this new analytical expression, in conjunction with the values of Jk, the SIFs can be computed without the need for an auxiliary relation. An example with known analytical solutions for SIFs is presented to show the variation of the J2‐integral near the crack tip of a bimaterial orthotropic plate. Different bimaterial combinations are considered, and the effect of material mismatch on Jk is demonstrated.
Nonlinear response of nitric oxide fluxes to fertilizer inputs and the impacts of agricultural intensification on tropospheric ozone pollution in Kenya
Authors: Hickman Jonathan E. , Huang Yaoxian , Wu Shiliang , Diru Willy , Groffman Peter M. , Tully Katherine L. , Palm Cheryl A.
Published: February 2017

Crop yields in sub‐Saharan Africa remain stagnant at 1 ton ha−1, and 260 million people lack access to adequate food resources. Order‐of‐magnitude increases in fertilizer use are seen as a critical step in attaining food security. This increase represents an unprecedented input of nitrogen (N) to African ecosystems and will likely be accompanied by increased soil emissions of nitric oxide (NO). NO is a precursor to tropospheric ozone, an air pollutant and greenhouse gas. Emissions of NO from soils occur primarily during denitrification and nitrification, and N input rates are a key determinant of emission rates. We established experimental maize plots in western Kenya to allow us to quantify the response function relating NO flux to N input rate during the main 2011 and 2012 growing seasons. NO emissions followed a sigmoid response to fertilizer inputs and have emission factors under 1% for the roughly two‐month measurement period in each year, although linear and step relationships could not be excluded in 2011. At fertilization rates above 100 kg N ha−1, NO emissions increased without a concomitant increase in yields. We used the geos‐chem chemical transport model to evaluate local impacts of increased NO emissions on tropospheric ozone concentrations. Mean 4‐hour afternoon tropospheric ozone concentrations in Western Kenya increased by up to roughly 2.63 ppbv under fertilization rates of 150 kg N ha−1 or higher. Using AOT40, a metric for assessing crop damage from ozone, we find that the increased ozone concentrations result in an increase in AOT40 exposure of approximately 110 ppbh for inputs of 150 kg N ha−1 during the March–April–May crop growing season, compared with unfertilized simulations, with negligible impacts on crop productivity. Our results suggest that it may be possible to manage Kenyan agricultural systems for high yields while avoiding substantial impacts on air quality.
Modelling habitat persistence and impacts of management on the habitats of an endangered butterfly
Authors: Fabritius Henna , McBride Marissa
Published: February 2017

In dynamic landscapes, effective species conservation requires an understanding of the spatial and temporal dynamics of species’ habitats.

In this study, vegetation data across differently aged sites, site management history data and expert elicitation are used to estimate (i) expected habitat patch lifetimes and (ii) the impacts of habitat management history on how habitat quality changes through time for an early‐successional habitat specialist, the endangered false heath fritillary butterfly (Melitaea diamina).

Results demonstrate the accelerated temporal dynamics experienced by false heath fritillary habitats, with the quality of false heath fritillary habitats peaking 2–3 years after management, and a median‐sized habitat patch initially without tree cover predicted to become unsuitable 15 years after management due to overgrowth.

As a co‐product of habitat management patterns, habitat succession and land use changes, non‐conserved false heath fritillary habitats had an expected lifetime of 13.1 years.

This study demonstrates a method that can be used to estimate habitat network dynamics for an early‐successional habitat specialist economically in situations where the urgency of conservation challenges favours fast decision‐making.
The “bundle” approach to reduce the surgical site infection rate
Authors: Bert Fabrizio , Giacomelli Sebastian , Amprino Viola , Pieve Giulio , Ceresetti Daniela , Testa Marco , Zotti Carla M.
Published: February 2017

Rationale, aims, and objectives

In Italy, since 2008, the surveillance of surgical site infections (SSIs) has been conducted following ECDC recommendations, according to the protocol of the National System of Surveillance of Surgical Site Infections.

In 2009, in Piedmont region, where the study was conducted, it was introduced a survey of a “bundle” for every patient under SSIs surveillance. The bundle includes 5 items: infection risk index calculation, preoperative shower, trichotomy, antibiotic prophylaxis, and body temperature control. The aim of this study is the evaluation of the incidence rate of the SSIs in relation to the implementation of the bundle from January 1st to December 31st, 2012.

Method

This study is an observational study (retrospective cohort). The regional surveillance system collected 3314 surgical operations during the year 2012 from 37 hospitals. The represented surgical categories were hip prosthetic surgery (HPRO: 1992 cases) and colon surgery (COLO: 1322 cases). The bundle was implemented in 1114 and 671 operations, respectively.

Univariate and multivariate analysis were conducted stratifying the sample for hip surgery and colorectal surgery, with the purpose to identify an association between the implementation of the bundle and a decrease of the rate of SSIs.

Results

From the analysis, the bundle resulted as a protective factor for the infection risk in colon surgery (odds ratio [OR], 0.55; 95% confidence interval [CI], 0.38‐0.78). The main risk factors were American Society of Anesthesiologists score ≥ 3 (OR, 1.57; 95% CI, 1.10‐2.24) and contamination class ≥ 3 (OR, 2.02; 95% CI, 1.37‐2.97). In the hip surgery, the application of the bundle was not statistically associated to a decrease of the risk of infection.

Conclusion

The use of surgical bundle seems to reduce significantly the SSIs rate in the colon surgery.
A multicenter, randomized, double‐blind clinical study to evaluate the efficacy and safety of a new monophasic hyaluronic acid filler with lidocaine 0.3% in the correction of nasolabial fold
Authors: Suh Joon Hyuk , Oh Chang Taek , Im Song I , Lim Jung Soo , Kim Beom Joon , Lee Jong Hun
Published: February 2017

Background

Many new brands of hyaluronic acid (HA) fillers are being introduced, but comparative research on the characteristics of similar products is limited.

Objective

To test the efficacy, tolerability, and safety of a HA filler with lidocaine, Dermalax implant plus™ (Across), which is used for correcting nasolabial folds (NLFs), and to compare the performance of that of Restylane Sub‐Q® (Q‐Med).

Methods

A total of 52 subjects with visible NLFs were enrolled in this randomized, multicenter, patient/evaluator‐blind, active‐controlled, matched‐pair clinical study. Each subject was injected with Dermalax implant plus™ in one NLF and Restylane Sub‐Q® in the other. All participants were reassessed for cosmetic changes at 2, 8, 12, 16, and 24 weeks. Wrinkle severity was rated using the 5‐point Wrinkle Severity Rating Scale (WSRS).

Results

At week 24, the mean improvement in the WSRS compared to baseline was 1.06±0.54 for the PLUS side and 0.69±0.58 for the Sub‐Q side (week 2: 1.67±0.58 and 1.21±0.67, week 8: 1.60±0.63 and 1.23±0.65, week 12: 1.58±0.61 and 1.15±0.61, week 16: 1.02±0.54 and 0.60±0.53). Average values of pain evaluated by self‐assessment 100‐mm VAS score within 30 minutes after the procedure in the PLUS and Sub‐Q groups were 14.65±16.23 and 38.29±27.27, respectively. Both fillers were well tolerated, and adverse reactions were mild.

Conclusion

We confirmed that the monophasic HA containing pre‐incorporated lidocaine (PLUS) is not inferior to well‐studied biphasic HA (Sub‐Q) in correcting to severe nasolabial folds for 24 weeks and less painful than biphasic HA not containing lidocaine.
Age of Sexual Debut and Physical Dating Violence Victimization: Sex Differences Among US High School Students
Authors: Ihongbe Timothy O. , Cha Susan , Masho Saba W.
Published: February 2017

ABSTRACT

BACKGROUND

Research has shown that early age of sexual debut is associated with physical dating violence (PDV), but sex‐specific associations are sparse. We estimated the prevalence of PDV victimization in high school students who have initiated sexual intercourse and examined sex‐specific association between age of sexual debut and PDV victimization.

METHODS

Data on 8637 students in grades 9 through 12 who had initiated sex was obtained from the 2009‐2011 national Youth Risk Behavior Survey. The association was examined using multiple logistic regression, accounting for the complex survey design, and stratified by sex.

RESULTS

Approximately 15% of sexually active students reported past‐year PDV victimization. The odds of PDV victimization among girls who had sexual debut at <12 years was 2.46 (95% CI = 1.50‐4.02) and 2.20 (95% CI = 1.42‐3.41) for boys, compared to those who initiated sex at 16 years and older.

CONCLUSIONS

Evidence supports the belief that early sexual debut is associated with higher odds of PDV victimization, particularly for girls. Healthcare providers, school counselors, and educators should be aware of this sex difference in the association between early sexual debut age and PDV victimization while focusing PDV interventions on adolescents with early sexual debut age.
Dark Side or Bright Light: Destructive and Constructive Deviant Content in Consumer Ideation Contests
Authors: Gatzweiler Alexandra , Blazevic Vera , Piller Frank Thomas
Published: February 2017

Firms use ideation contests to generate ideas from consumers. This type of collaboration provides access to new knowledge and reveals latent consumer needs. But it also is risky, as firms give up control to an unknown crowd. Some contestants use ideation contests to post content that is unintended and unwanted by contest hosts, a behavior that represents deviant co‐creation. Drawing on literature from sociology and consumer research, deviance is defined as a relative, norm‐violating behavior that has the potential to activate others. We report the results from a netnography study to define the phenomenon of deviant co‐creation in ideation contests. Based on these findings, we provide a theoretical foundation for deviant co‐creation and conceptualize and empirically illustrate various patterns of deviant content, ranging from destructive to constructive. The study reveals that deviant content in ideation contests includes illegitimate as well as legitimate content. Legitimate content includes five themes: humorous, provocative, unique, violation from technical, and social norms. Deviant content usually bewilders evaluators and draws their attention to the content. Destructive deviant content may trigger visible and malicious protests or result in mocking and ridicule on the contest platform and other social media, thereby exposing the contest host to reputational risks. Constructive deviant content can lead to positive discussions in comment sections and other social media outlets, as well as foster further development of an initial idea, thereby contributing to the firm's innovation potential. This article provides managers a deeper understanding of deviant content raising awareness for the dark side risks as well as indicating how to leverage it to achieve constructive co‐creation.
Prevalence and Risk Factors for Presumptive Ascending/Descending Myelomalacia in Dogs after Thoracolumbar Intervertebral Disk Herniation
Authors: Balducci F. , Canal S. , Contiero B. , Bernardini M.
Published: February 2017

Background

Ascending/descending myelomalacia (ADMM) is a severe complication of thoracolumbar intervertebral disk herniation (TL‐IVDH) in dogs.

Hypothesis/Objectives

To investigate the prevalence and risk factors for ADMM in nonambulatory dogs with surgically treated TL‐IVDH.

Animals

Six‐hundred and fifty‐two client‐owned dogs evaluated for TL‐IVDH that underwent decompressive spinal surgery.

Methods

Retrospective medical record review from February 2007 through December 2015.

Results

Thirteen dogs developed ADMM, with an overall prevalence of 2.0%. The prevalence of ADMM was 0% in dogs with neurological signs graded 1 or 2 at admission or before magnetic resonance imaging (MRI) or surgical procedures, 0.6% in dogs with neurological signs graded 3, 2.7% in dogs with neurological signs graded 4, and 14.5% in dogs with neurological signs graded 5. Age (<5.8 years), neurological status (grade 5), site of disk herniation (L5‐L6), duration of clinical signs before becoming nonambulatory (<24 hours), detection of intramedullary T2‐weighted (T2W) hyperintensity, and a T2 length ratio >4.57 were significant risk factors in the univariate analysis for development of ADMM.

Conclusions and Clinical Importance

The factors identified in this study may be useful for the prediction of ADMM. Multicenter studies with a higher number of dogs with ADMM are required to confirm these data.
Thermal tolerance in the keystone species Daphnia magna—a candidate gene and an outlier analysis approach
Authors: Jansen M. , Geerts A. N. , Rago A. , Spanier K. I. , Denis C. , De Meester L. , Orsini L.
Published: February 2017

Changes in temperature have occurred throughout Earth's history. However, current warming trends exacerbated by human activities impose severe and rapid loss of biodiversity. Although understanding the mechanisms orchestrating organismal response to climate change is important, remarkably few studies document their role in nature. This is because only few systems enable the combined analysis of genetic and plastic responses to environmental change over long time spans. Here, we characterize genetic and plastic responses to temperature increase in the aquatic keystone grazer Daphnia magna combining a candidate gene and an outlier analysis approach. We capitalize on the short generation time of our species, facilitating experimental evolution, and the production of dormant eggs enabling the analysis of long‐term response to environmental change through a resurrection ecology approach. We quantify plasticity in the expression of 35 candidate genes in D. magna populations resurrected from a lake that experienced changes in average temperature over the past century and from experimental populations differing in thermal tolerance isolated from a selection experiment. By measuring expression in multiple genotypes from each of these populations in control and heat treatments, we assess plastic responses to extreme temperature events. By measuring evolutionary changes in gene expression between warm‐ and cold‐adapted populations, we assess evolutionary response to temperature changes. Evolutionary response to temperature increase is also assessed via an outlier analysis using EST‐linked microsatellite loci. This study provides the first insights into the role of plasticity and genetic adaptation in orchestrating adaptive responses to environmental change in D. magna.