bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantification of surface tension and internal pressure generated by single mitotic cells
Authors: Fischer-Friedrich Elisabeth , Hyman Anthony A. , Jülicher Frank , Müller Daniel J. , Helenius Jonne 
Published: August 2014

AbstractDuring mitosis, adherent cells round up, by increasing the tension of the contractile actomyosin cortex while increasing the internal hydrostatic pressure. In the simple scenario of a liquid cell interior, the surface tension is related to the local curvature and the hydrostatic pressure difference by Laplace's law. However, verification of this scenario for cells requires accurate measurements of cell shape. Here, we use wedged micro-cantilevers to uniaxially confine single cells and determine confinement forces while concurrently determining cell shape using confocal microscopy. We fit experimentally measured confined cell shapes to shapes obeying Laplace's law with uniform surface tension and find quantitative agreement. Geometrical parameters derived from fitting the cell shape and the measured force were used to calculate hydrostatic pressure excess and surface tension of cells. We find that HeLa cells increase their internal hydrostatic pressure excess and surface tension from ≈ 40 Pa and 0.2 mNm−1 during interphase to ≈ 400 Pa and 1.6 mNm−1 during metaphase. The method introduced provides a means to determine internal pressure excess and surface tension of rounded cells accurately and with minimal cellular perturbation and should be applicable to characterize the mechanical properties of various cellular systems.
Antibody-coupled monolithic silica microtips for highthroughput molecular profiling of circulating exosomes
Authors: Ueda Koji , Ishikawa Nobuhisa , Tatsuguchi Ayako , Saichi Naomi , Fujii Risa , Nakagawa Hidewaki 
Published: August 2014

AbstractExosome-mediated signal transportation plays a variety of critical roles in cancer progression and metastasis. From the aspect of cancer diagnosis, circulating exosomes are ideal resources of biomarkers because molecular features of tumor cells are transcribed on them. However, isolating pure exosomes from body fluids is time-consuming and still major challenge to be addressed for comprehensive profiling of exosomal proteins and miRNAs. Here we constructed anti-CD9 antibody-coupled highly porous monolithic silica microtips which allowed automated rapid and reproducible exosome extraction from multiple clinical samples. We applied these tips to explore lung cancer biomarker proteins on exosomes by analyzing 46 serum samples. The mass spectrometric quantification of 1,369 exosomal proteins identified CD91 as a lung adenocarcinoma specific antigen on exosomes, which was further validated with CD9-CD91 exosome sandwich ELISA measuring 212 samples. Our simple device can promote not only biomarker discovery studies but also wide range of omics researches about exosomes.
An optical sensor for detecting the contact location of a gas-liquid interface on a body
Authors: Belden Jesse , Jandron Michael 
Published: August 2014

An optical sensor for detecting the dynamic contact location of a gas-liquid interface along the length of a body is described. The sensor is developed in the context of applications to supercavitating bodies requiring measurement of the dynamic cavity contact location; however, the sensing method is extendable to other applications as well. The optical principle of total internal reflection is exploited to detect changes in refractive index of the medium contacting the body at discrete locations along its length. The derived theoretical operation of the sensor predicts a signal attenuation of 18 dB when a sensed location changes from air-contacting to water-contacting. Theory also shows that spatial resolution (d) scales linearly with sensor length (Ls) and a resolution of 0.01Ls can be achieved. A prototype sensor is constructed from simple components and response characteristics are quantified for different ambient light conditions as well as partial wetting states. Three methods of sensor calibration are described and a signal processing framework is developed that allows for robust detection of the gas-liquid contact location. In a tank draining experiment, the prototype sensor resolves the water level with accuracy limited only by the spatial resolution, which is constrained by the experimental setup. A more representative experiment is performed in which the prototype sensor accurately measures the dynamic contact location of a gas cavity on a water tunnel wall.
The Evolution of Singlish: Beyond Phase 5?
Authors: Wee Lionel 
Published: August 2014

This paper focuses on the development of Singlish and shows that the study of Singlish provides us with useful information about how the development of (varieties of) English is related to issues of language, identity and culture in a rapidly globalizing world. As such, it raises the important question of how the issue of global mobility (of people as well as cultural – including linguistic – products) can be linked to Schneider’s Dynamic Model. The basic assumptions of the Dynamic Model, the paper argues, will need to be reconsidered if it is to keep pace with the sociolinguistic implications of globalization.
The evolution of English(es)
Authors: Hackert Stephanie 
Published: August 2014

Many of the central tenets of modern linguistics – and thus also of the study of World Englishes – have a history which goes back to the nineteenth century. This article focuses on the idea of the evolution of language(s). I will employ a discourse-historical approach to show that evolution was generally taken to imply not only progress but also hierarchization, and that English and its standard variety – as well as their speakers – were inevitably seen as the most progressive and placed at the top of any linguistic hierarchy. Of course, crude nationalist and racist thinking are no longer current in academic linguistics today; nevertheless, this article will claim that in order to fully comprehend contemporary ideologies of language, we need to understand the historical origins of the assumptions and beliefs upon which they rest.
Price Explosiveness, Speculation, and Grain Futures Prices
Authors: Etienne Xiaoli L. , Irwin Scott H. , Garcia Philip 
Published: August 2014

AbstractA recently developed testing procedure is used to detect and date‐stamp explosive episodes (“bubbles”) in corn, soybean, and wheat futures markets during 2004–2013. We find that the markets experienced price explosiveness only approximately two percent of the time and, when bubbles do occur, they are generally short‐lived and small in magnitude. The correspondence between observed price spikes and bubbles is rather low, with a large portion of the price explosiveness occurring during downward price movements. Commodity index trader positions do not significantly affect the probability of a positive bubble occurring in grain futures markets, which directly contradicts the argument (the “Masters Hypothesis”) that waves of index investment distorted underlying supply‐and‐demand relationships and led to a series of massive bubbles in agricultural futures markets. In addition, commodity index trader positions tend to reduce negative bubble occurrence, while general speculative activity as measured by Working's T reduces the probability of a positive bubble. There is some evidence that the positions of noncommercial traders have a direct effect on positive bubble occurrence, but the effect declines when accounting for the composition of other traders in the market. Overall, speculation has little effect or negative effects on price explosiveness. Finally, positive bubbles are more likely to occur in the presence of low inventories, strong exports, a weak U.S. dollar, and booming economic growth, whereas negative bubbles are more likely to occur with large inventories, weak exports, and stagnant economic growth.
Cell population identification using fluorescence-minus-one controls with a one-class classifying algorithm
Authors: Feher Kristen , Kirsch Jenny , Radbruch Andreas , Chang Hyun-Dong , Kaiser Toralf 
Published: August 2014

Abstract
Motivation: The tried and true approach of flow cytometry data analysis is to manually gate on each biomarker separately, which is feasible for a small number of biomarkers, e.g. less than five. However, this rapidly becomes confusing as the number of biomarker increases. Furthermore, multivariate structure is not taken into account. Recently, automated gating algorithms have been implemented, all of which rely on unsupervised learning methodology. However, all unsupervised learning outputs suffer the same difficulties in validation in the absence of external knowledge, regardless of application domain.
Results: We present a new semi-automated algorithm for population discovery that is based on comparison to fluorescence-minus-one controls, thus transferring the problem into that of one-class classification, as opposed to being an unsupervised learning problem. The novel one-class classification algorithm is based on common principal components and can accommodate complex mixtures of multivariate densities. Computational time is short, and the simple nature of the calculations means the algorithm can easily be adapted to process large numbers of cells (106). Furthermore, we are able to find rare cell populations as well as populations with low biomarker concentration, both of which are inherently hard to do in an unsupervised learning context without prior knowledge of the samples’ composition.
Availability and implementation: R scripts are available via https://fccf.mpiib-berlin.mpg.de/daten/drfz/bioinformatics/with{username,password}={bioinformatics,Sar=Gac4}.
Contact: kristen.feher@drfz.de or kaiser@drfz.de
Supplementary information: Supplementary data are available at Bioinformatics online.
RVboost: RNA-seq variants prioritization using a boosting method
Authors: Wang Chen , Davila Jaime I. , Baheti Saurabh , Bhagwate Aditya V. , Wang Xue , Kocher Jean-Pierre A. , Slager Susan L. , Feldman Andrew L. , Novak Anne J. , Cerhan James R. , Thompson E. Aubrey , Asmann Yan W. 
Published: August 2014

Abstract
Motivation: RNA-seq has become the method of choice to quantify genes and exons, discover novel transcripts and detect fusion genes. However, reliable variant identification from RNA-seq data remains challenging because of the complexities of the transcriptome, the challenges of accurately mapping exon boundary spanning reads and the bias introduced during the sequencing library preparation.
Method: We developed RVboost, a novel method specific for RNA variant prioritization. RVboost uses several attributes unique in the process of RNA library preparation, sequencing and RNA-seq data analyses. It uses a boosting method to train a model of ‘good quality’ variants using common variants from HapMap, and prioritizes and calls the RNA variants based on the trained model. We packaged RVboost in a comprehensive workflow, which integrates tools of variant calling, annotation and filtering.
Results: RVboost consistently outperforms the variant quality score recalibration from the Genome Analysis Tool Kit and the RNA-seq variant-calling pipeline SNPiR in 12 RNA-seq samples using ground-truth variants from paired exome sequencing data. Several RNA-seq–specific attributes were identified as critical to differentiate true and false variants, including the distance of the variant positions to exon boundaries, and the percent of the reads supporting the variant in the first six base pairs. The latter identifies false variants introduced by the random hexamer priming during the library construction.
Availability and implementation: The RVboost package is implemented to readily run in Mac or Linux environments. The software and user manual are available at http://bioinformaticstools.mayo.edu/research/rvboost/.
Supplementary information: Supplementary data are available at Bioinformatics online.
Testing the neutrino annihilation model for launching GRB jets
Authors: Leng Mingbin , Giannios Dimitrios 
Published: August 2014

Abstract
The mechanism behind the launching of gamma-ray burst (GRB) jets remains debated resulting in large uncertainty over the jet composition. Both magnetohydrodynamical and neutrino annihilation models have been proposed for the energy extraction in a black hole/accretion-disc central engine. In particular, for the extreme accretion rates $\dot{M}\sim 0.1\hbox{--}1$ M⊙ s−1 expected for bursts of duration T ≲ 100 s, the disc can be an efficient neutrino emitter. Neutrino–antineutrino annihilation results in an energy deposition rate at the jet that can, in principle, account for the burst's energetics. Recent discoveries of X-ray flares hours after the burst and of ultra-long GRBs suggest that GRB activity can last for ∼104 s or longer. These long-lived events have fluence similar to that of classical GRBs. In view of these findings, we re-evaluate the neutrino annihilation model. We derive the maximum possible energy of a neutrino-powered jet as a function of the burst duration and show that the available energy drops fast for longer bursts. For a standard choice of the parameters, the model falls short by three to four orders of magnitude in explaining the observed energetics of events that last longer than ∼103 s.
Andromeda II as a merger remnant
Authors: Łokas Ewa L. , Ebrová Ivana , Pino Andrés del , Semczuk Marcin 
Published: August 2014

Abstract
Using N-body simulations, we study the origin of prolate rotation observed in the kinematic data for Andromeda II (And II), a dwarf spheroidal satellite of M31. We propose an evolutionary model for the origin of And II involving a merger between two discy dwarf galaxies with different disc scalelengths. The dwarfs are placed on a radial orbit towards each other with their angular momenta inclined by 90 deg. The merger remnant forms a stable triaxial galaxy with rotation only around the longest axis whose origin is naturally explained as due to the symmetry of the initial configuration and the conservation of angular momentum components along the direction of the merger. The stars originating from the two dwarfs show significantly different surface density profiles while having very similar kinematics as required by the data. We also study an alternative scenario for the formation of And II, via tidal stirring of a discy dwarf. While intrinsic rotation occurs naturally in this model as a remnant of the initial rotation of the disc, it is mostly around the shortest axis of the stellar component. We conclude that the velocity distribution in And II is much more naturally explained by a scenario involving a past merger.
Bayesian Multilevel MIMIC Modeling for Studying Measurement Invariance in Cross-group Comparisons
Authors: Bruyneel Luk , Li Baoyue , Squires Allison , Spotbeen Sara , Meuleman Bart , Lesaffre Emmanuel , Sermeus Walter 
Published: August 2014

Background:
Recent methodological advancements should catalyze the evaluation of measurement invariance across groups, which is required for conducting meaningful cross-group comparisons.

Objective:
The aim of this study was to apply a state-of-the-art statistical method for comparing latent mean scores and evaluating measurement invariance across managers’ and frontline workers’ ratings of the organization of hospital care.

Methods:
On the 87 nursing units in a single institution, French-speaking and Dutch-speaking nursing unit managers’ and staff nurses’ ratings of their work environment were measured using the multidimensional 32-item practice environment scale of the nursing work index (PES-NWI). Measurement invariance and latent mean scores were evaluated in the form of a Bayesian 2-level multiple indicators multiple causes model with covariates at the individual nurse and nursing unit level. Role (manager, staff nurse) and language (French, Dutch) are of primary interest.

Results:
Language group membership accounted for 7 of 11 PES-NWI items showing measurement noninvariance. Cross-group comparisons also showed that covariates at both within-level and between-level had significant effects on PES-NWI latent mean scores. Most notably, nursing unit managers, when compared with staff nurses, hold more positive views of several PES-NWI dimensions.

Conclusions:
Using a widely used instrument for measuring nurses’ work environment, this study shows that precautions for the potential threat of measurement noninvariance are necessary in all stages of a study that relies on survey data to compare groups, particularly in multilingual settings. A Bayesian multilevel multiple indicators multiple causes approach can accommodate for detecting all possible instances of noninvariance for multiple covariates of interest at the within-level and between-level jointly.
The Genetic Architecture of Gene Expression Levels in Wild Baboons
Authors: Tung Jenny , Zhou Xiang , Alberts Susan C , Stephens Matthew , Gilad Yoav 
Published: August 2014

ABSTRACTGene expression variation is well documented in human populations and its genetic architecture has been extensively explored. However, we still know little about the genetic architecture of gene expression variation in other species, particularly our closest living relatives, the nonhuman primates. To address this gap, we performed an RNA sequencing (RNA-seq)-based study of 63 wild baboons, members of the intensively studied Amboseli baboon population in Kenya. Our study design allowed us to measure gene expression levels and identify genetic variants using the same data set, enabling us to perform complementary mapping of putativecis-acting expression quantitative trait loci (eQTL) and measurements of allele-specific expression (ASE) levels. We discovered substantial evidence for genetic effects on gene expression levels in this population. Surprisingly, we found more power to detect individual eQTL in the baboons relative to a HapMap human data set of comparable size, probably as a result of greater genetic variation, enrichment of SNPs with high minor allele frequencies, and longer-range linkage disequilibrium in the baboons. eQTL were most likely to be identified for lineage-specific, rapidly evolving genes. Interestingly, genes with eQTL significantly overlapped between the baboon and human data sets, suggesting that some genes may tolerate more genetic perturbation than others, and that this property may be conserved across species. Finally, we used a Bayesian sparse linear mixed model to partition genetic, demographic, and early environmental contributions to variation in gene expression levels. We found a strong genetic contribution to gene expression levels for almost all genes, while individual demographic and environmental effects tended to be more modest. Together, our results establish the feasibility of eQTL mapping using RNA-seq data alone, and act as an important first step towards understanding the genetic architecture of gene expression variation in nonhuman primates.
C. elegansharbors pervasive cryptic genetic variation for embryogenesis
Authors: Paaby Annalise B. , White Amelia G. , Riccardi David D. , Gunsalus Kristin C. , Piano Fabio , Rockman Matthew V. 
Published: August 2014

ABSTRACTConditionally functional mutations are an important class of natural genetic variation, yet little is known about their prevalence in natural populations or their contribution to disease risk. Here, we describe a vast reserve of cryptic genetic variation, alleles that are normally silent but which affect phenotype when the function of other genes is perturbed, in the gene networks ofC. elegansembryogenesis. We find evidence that cryptic-effect loci are ubiquitous and segregate at intermediate frequencies in the wild. The cryptic alleles demonstrate low developmental pleiotropy, in that specific, rather than general, perturbations are required to reveal them. Our findings underscore the importance of genetic background in characterizing gene function and provide a model for the expression of conditionally functional effects that may be fundamental in basic mechanisms of trait evolution and the genetic basis of disease susceptibility.
Easy access: a case study on rural marketing
Authors: Ranjan Parida Rashmi , Sahney Sangeeta 
Published: August 2014

Subject area
Marketing management and marketing strategy, rural marketing, sales and distribution.

Study level/applicability
Students of business schools specialising in the area of marketing or rural marketing.

Case overview
The case focuses on the rural market. It deals with the alternative distribution channels adopted for last mile distribution among rural consumers of underdeveloped Odisha (India). The case discusses key issues pertaining to rural marketing, business viability, social issues and public sentiment.Easy access is an entrepreneurial venture by an erstwhile intellectual marketing professor of a premier B-school. The objective behind this initiative is multiple, viz., rural marketing, developing alternative distribution networks, women empowerment, etc. The case highlights that the business of Easy Access started with noble social objectives like women empowerment and developing a cost effective distribution network so that rural customers would be benefited. The case also highlights that the practices adopted by Easy access was not good enough to track & forecast demand effectively as well as the supply chain to replenish stock was not proper.Since the particular market is a backward region and there are number of Govt. schemes and people are given many things for free. People thought Easy Access is result of one of such schemes. Also there were social issues of improper address and mismatch identity (as mentioned in the case) etc.So the issues of demand forecasting and supply chain management along with social issues resulted in financial loss and thus the viability of business venture (Easy Access) is a concern. The social objectives associated with this venture are also at stake or at danger because of financial loss.

Expected learning outcomes
The case provides insights into the marketing concepts like rural marketing, marketing strategy in emerging markets and sales and distribution.

Supplementary materials
Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.
Motives for reading and articulating user-generated restaurant reviews on Yelp.com
Authors: Parikh Anish , Behnke Carl , Vorvoreanu Mihaela , Almanza Barbara , Nelson Doug 
Published: August 2014

Purpose
– The purpose of this research is to examine why and when restaurant consumers use and contribute user-generated reviews. This research is needed to determine the relevance of user-generated restaurant reviews in the current marketplace.

Design/methodology/approach
– The research methodology is based on a quantitative approach, and focused on current Yelp.com users as its population. Questions focused on the amount of usage, motives for usage, level of trust, users’ tendencies to seek novelty in restaurants and motives for contribution.

Findings
– Users tend to trust the reviews on Yelp.com and engage in the community aspects of the platform. Yelp.com users also are altruistic in their motivation for contributing reviews to Yelp.com. Yelp.com users who access it tend to act on the information found within the reviews.

Originality/value
– Research articles have focused on user-generated reviews in the past; however, few have examined motivations of using and posting restaurant reviews. The value of conducting research comes from being able to understand the importance of user-generated restaurant reviews for customers in a comprehensive manner.