bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cell-cell communication enhances the capacity of cell ensembles to sense shallow gradients during morphogenesis
Authors: Ellison David , Mugler Andrew , Brennan Matthew , Lee Sung Hoon , Huebner Robert , Shamir Eliah , Woo Laura A. , Kim Joseph , Amar Patrick , Nemenman Ilya , Ewald Andrew J. , Levchenko Andre 
Published: August 2015

AbstractCollective cell responses to exogenous cues depend on cell-cell interactions. In principle, these can result in enhanced sensitivity to weak and noisy stimuli. However, this has not yet been shown experimentally, and, little is known about how multicellular signal processing modulates single cell sensitivity to extracellular signaling inputs, including those guiding complex changes in the tissue form and function. Here we explored if cell-cell communication can enhance the ability of cell ensembles to sense and respond to weak gradients of chemotactic cues. Using a combination of experiments with mammary epithelial cells and mathematical modeling, we find that multicellular sensing enables detection of and response to shallow Epidermal Growth Factor (EGF) gradients that are undetectable by single cells. However, the advantage of this type of gradient sensing is limited by the noisiness of the signaling relay, necessary to integrate spatially distributed ligand concentration information. We calculate the fundamental sensory limits imposed by this communication noise and combine them with the experimental data to estimate the effective size of multicellular sensory groups involved in gradient sensing. Functional experiments strongly implicated intercellular communication through gap junctions and calcium release from intracellular stores as mediators of collective gradient sensing. The resulting integrative analysis provides a framework for understanding the advantages and limitations of sensory information processing by relays of chemically coupled cells.
Agricultural credit and economic growth in rural areas
Authors: Hartarska Valentina , Nadolnyak Denis , Shen Xuan 
Published: August 2015

Purpose
– In this paper, the authors set out to establish if there is a link between finance and economic growth in rural areas. The purpose of this paper is to evaluate the relation between credit by major lenders in rural areas – commercial banks and Farm Credit System (FCS) institutions – and economic growth for the period 1991-2010.

Design/methodology/approach
– The motivation for this work comes from empirical studies showing a link between economic development and financial system development as well as from work which highlights the positive role of long-term finance provided by banks. The authors use two alternative panel data sets and fixed effects models to estimate the causal effect of credit supply (with lagged explanatory variables) on agricultural GDP growth per rural resident.

Findings
– The authors find a positive association between agricultural lending and agricultural GDP growth per rural resident with additional billion in loans (about a third of the actual average) associated with 7-10 percent higher state growth rate with this association stronger during the 1990s. Regional data confirm these results. The results point to a positive link between credit and economic growth in rural areas during that period, attributable to the lending by FCS institutions and by commercial banks.

Research limitations/implications
– Data availability limits the scope of this paper. The authors use state level balance sheet data available for the 1991-2003 period and annual data for 2003-2010 period. An additional regional data set is constructed for 1991-2010 with more aggregated data for the ten USDA agricultural production regions. The small number of panels limits the ability to use more sophisticated econometric models and the choice of dependent variables that captures economic growth.

Practical implications
– By provides evidence that agricultural finance and in particular lending contribute significantly to the growth of US agriculture, this paper contributes to the policy debate on weather support for agricultural finance initiatives is justified.

Originality/value
– The authors are not aware of another study that has linked agricultural lending by commercial banks and FCS institutions to growth in rural areas in the USA.
Does federal crop insurance lead to higher farm debt use? Evidence from the Agricultural Resource Management Survey (ARMS)
Authors: Ifft Jennifer E , Kuethe Todd , Morehart Mitch 
Published: August 2015

Purpose
– The purpose of this paper is to consider how the federal crop insurance (FCI) program influences farm debt use, one of the key financial decisions made by farm operators.

Design/methodology/approach
– Using data from the nationally representative Agricultural Resource Management Survey, the paper implements a propensity score matching model of the impact of FCI participation on various measures of farm business debt use. To account for the simultaneity of financial decisions, the paper further tests this relationship using a seemingly unrelated regression model.

Findings
– FCI participation is associated with an increase in use of short-term farm debt, but not long-term debt, consistent with risk balancing behavior and current trends in the farm sector.

Research limitations/implications
– In addition to risk balancing, the results are also consistent with credit constraints or lender preferences. The paper cannot fully establish causality between crop insurance participation and short-term debt levels. Future research should address these limitations.

Practical implications
– Agricultural lending standards are generally conservative and the farm sector as a whole currently has historically low leverage, which implies that an increase in debt use may not be a threat to the financial health of the farm sector.

Social implications
– The results indicate that the reduction in total risk facing the farm sector is significantly less than the decline in risk provided by FCI, which is an important consideration for policymakers.

Originality/value
– This is the first paper to use an econometric model to analyze the relationship between FCI and farm debt use decisions. This paper can inform future research on the FCI program and farm financial decisions.
Geographical diversification in wheat farming: a copula-based CVaR framework
Authors: Larsen Ryan , Leatham David , Sukcharoen Kunlapath 
Published: August 2015

Purpose– Portfolio theory suggests that geographical diversification of production units could potentially help manage the risks associated with farming, yet little research has been done to evaluate the effectiveness of a geographical diversification strategy in agriculture. The paper aims to discuss this issue.Design/methodology/approach– The paper utilizes several tools from modern finance theory, including Conditional Value-at-Risk (CVaR) and copulas, to construct a model for the evaluation of a diversification strategy. The proposed model – the copula-based mean-CVaR model – is then applied to the producer’s acreage allocation problem to examine the potential benefits of risk reduction from a geographical diversification strategy in US wheat farming. Along with the copula-based model, the multivariate-normal mean-CVaR model is also estimated as a benchmark.Findings– The mean-CVaR optimization results suggest that geographical diversification is a viable risk management strategy from a farm’s profit margin perspective. In addition, the copula-based model appears more appropriate than the traditional multivariate-normal model for conservative agricultural producers who are concerned with the extreme losses of farm profitability in that the later model tends to underestimate the minimum level of risk faced by the producers for a given level of profitability.Originality/value– The effectiveness of geographical diversification in US wheat farming is evaluated. As a methodological contribution, the copula approach is used to model the joint distribution of profit margins and CVaR is employed as a measure of downside risk.
A field study for assessing risk-contingent credit for Kenyan pastoralists and dairy farmers
Authors: Shee Apurba , Turvey Calum G. , Woodard Joshua 
Published: August 2015

Purpose
– The purpose of this paper is to assess the feasibility of risk-contingent credit (RCC) by presenting an experimental and participatory game designed to explain the concept of RCC to Kenyan pastoralists and dairy farmers. The paper investigates the uptake potential of RCC through qualitative assessment of field experiments and focus groups.

Design/methodology/approach
– The paper presents a method of community engagement through a participatory game played in a series of Focus Group Discussions (FGDs). The paper also presents theoretical justification of RCC in credit market structure.

Findings
– The game effectively explains the concept and mechanism of RCC by reflecting local situation and production potential. Participatory exercises within focus group discussions indicate that there exists a strong interest and support for RCC.

Research limitations/implications
– The methodology described in this paper can be used in extension programs for promoting innovative rural microcredit in developing countries but should be modified according to the local production and associated weather and market risks.

Originality/value
– Micro-insurance and credit program delivery can be improved by the innovative approach of community engagement for explaining financial products.
Structural mapping of public distribution system using multi-agent systems
Authors: Ambekar Sudhir , Kapoor Rohit , Mehta Peeyush 
Published: August 2015

Purpose
– The purpose of this paper is to develop a framework for mapping the Indian Public Distribution System (PDS) using multi-agent system (MAS). The entire PDS supply chain from purchase to the distribution is mapped in detail by integrating stages of PDS supply chain.

Design/methodology/approach
– Literature related to PDS, food grain supply chain (FGSC) and MAS is reviewed and critically assessed. Based on this a framework is proposed which will help in improving functioning of PDS.

Findings
– The PDS has many shortcomings arising from its complex structure and practices which are used to implement it. The authors propose an MAS to model it in which each entity will be modelled as an agent. The authors propose two stages of supply chain. First stage models the processes from procurement to storage of food grain and second stage model the distribution process.

Practical implications
– This paper will be of interest to the policy makers and decision makers involved in the PDS by providing the shortfalls in the system and also suggesting a method to model the PDS based on practices of food supply chains.

Originality/value
– This paper provides the decision makers in the PDS, a framework to model and assess the entire supply chain. This will help them in effective implementation of the PDS and also improve in the areas of concerns which are pointed the study.
Patient-journey modelling and simulation in computed tomography
Authors: Samaranayake Premaratne , Dadich Ann , Hayes Kate J , Sloan Terrence 
Published: August 2015

Purpose– The purpose of this paper is to present a business process reengineering (BPR) framework of process and data integration with patient journey as the basis for process evaluation and the improvement of patient-flow.Design/methodology/approach– A BPR framework is developed using a mixed-method research design, which incorporated a case study to demonstrate a healthcare scenario with associated processes and data elements, using process models based on event-driven process chain methodology as well as patient and data models, based on unitary structuring technique. The framework includes key processes including patient booking and rebooking, and associated inputs, outputs, and control parameters. In this case, the framework is demonstrated through application to computed tomography (CT) services in a hospital to improve patient-flow, with numerical simulation of CT data collected over time.Findings– The framework supports flexible patient scheduling and the associated planning of healthcare operations and logistics – this in turn helps to improve patient-flow. Furthermore, mathematical modelling and simulation precisely reveal the impact of booking and rebooking on the performance of the CT department.Research limitations/implications– This innovative framework has potential value for other services, within and beyond the hospital setting.Originality/value– The proposed framework of process modelling, data, and patient journey addresses the lack of a holistic approach to monitoring and evaluating service performance in hospital settings. Patient journey modelling is an integral part of process and data models that can be implemented in an integrated system environment such as an enterprise resource planning system for real-time monitoring of patient-flow under dynamic conditions.
College students’ awareness in organizational strategy use in English writing
Authors: Chien Shih-Chieh 
Published: August 2015

Purpose
– The purpose of the study is to look at Chinese English as a foreign language (EFL) learners’ organizational strategy use in English writing at universities in Taiwan. One significant area that has been indicated in contrastive rhetoric studies spins around the notion of culturally constructed organizational patterns. It is claimed that second language (L2) writers may have implicit culturally driven presuppositions and values about academic writing in the first language (L1) that may transfer straightforwardly to academic writing in English.

Design/methodology/approach
– Data were from 50 high- and 50 low-achieving EFL students’ and 50 native English speakers’ (NESs’) written texts, and semi-structured interviews with EFL students and their teachers.

Findings
– Based on text analysis, when high-achieving EFL students and NESs were compared, they were similar in location of thesis, existence of introduction, existence of topic sentences, macro-level patterns, existence of conclusion, existence of a concluding sentence and existence of a final comment, but different in existence of background information. Nonetheless, it is noted that low-achieving EFL students were quite different from high-achieving EFL students and NESs in several aspects, such as location of thesis, existence of introduction, existence of topic sentences, macro-level patterns, existence of conclusion, existence of a concluding sentence, and existence of a final comment. In addition, the written texts and interview findings suggest that while cultural differences do, in fact, exist, Chinese writers’ English organizational strategy use were to some extent intertwined with their writing experiences and teachers’ writing instructions. The results also suggest the flexibility of writers and multiplicity of writing experiences within a cultural group.

Originality/value
– The study makes original recommendations for language pedagogy.
Teaching spoken English in Iran’s private language schools: issues and options
Authors: Sadeghi Karim , Richards Jack C. 
Published: August 2015

Purpose
– Mastery of spoken English is a priority for many learners of English in Iran. Opportunities to acquire spoken English through the public school system are very limited, hence many students enroll in “conversation” courses in private institutes. The purpose of this paper is to report a study of how institute teachers address the teaching of spoken English.

Design/methodology/approach
– Eighty-nine teachers completed a questionnaire on how they teach spoken English. The information was supplemented with interviews and classroom observation.

Findings
– Results suggest that institute courses reflect a poor understanding of the nature of spoken interaction, which is reflected in speaking courses that are unfocused and that do not address key aspects of conversational interaction.

Practical implications
– Suggestions are given for a re-examination of the differences between “conversation” and “discussion” in spoken English classes as the basis for designing spoken English classes and materials, as well as for the use of out-of-class learning opportunities to enhance the learning of spoken English in Iran and elsewhere.

Originality/value
– This paper is based on the authors’ original research, and the authors believe this is the first study of its kind in the Iranian context.
Gender perspectives on university education and entrepreneurship
Authors: Tegtmeier Silke , Mitra Jay 
Published: August 2015

Purpose– The purpose of this paper is to direct attention to recent research on women’s entrepreneurship with a focus on university education. A literature review and a summary of authors’ selected papers provide both a context for and an introduction to the articles in this special issue.Design/methodology/approach– This introduction provides an overview of the literature on female entrepreneurship with specific reference to the context of university education. Searches on Web of Science and in this journal were conducted to provide a systematic overview of the area of research. This introductory article ends with a set of propositions for future research engagement.Findings– This paper finds that the quantum of past research endeavours remains limited despite the growing significance of the subject. This paper also finds that developing a focused approach that is based on a female ontology of entrepreneurship, and one that identifies specific contexts, and appropriate methodological considerations that enable enquiry at different levels, are of value to future research. This paper offers four different propositions that address key areas or fields of entrepreneurship research.Research limitations/implications– This paper provides a unique set of propositions together with a framework which helps to both explore new knowledge creation and locate new research within the main fields of entrepreneurship while providing room for extending those fields.Practical implications– This overview provides a framework for universities and policymakers to enable them to take into consideration the critical issues of entrepreneurship in general, and female entrepreneurship in particular, when developing programmes and tools for university education.Originality/value– This paper provides a summary of the trends in research on women’s entrepreneurship with reference to university education. This leads to the development of a set of propositions and a framework for identifying and exploring new research questions that need to be addressed to close important research gaps in the field of entrepreneurship.
Investigation of oxygen followed by argon plasma treatment on LED chip bond pad for wire bond application
Authors: Peng Hui Yuen , Devarajan Mutharasu , Lee Teik Toon , Lacey David 
Published: August 2015

Purpose
– The purpose of this paper is to investigate the efficiencies of argon (Ar), oxygen (O2) and O2 followed by Ar (O2→Ar) plasma treatments in terms of contaminant removal and wire bond interfacial adhesion improvement. The aim of this study is to resolve the “lifted ball bond” issue, which is one of the critical reliability checkpoints for light emitting diodes (LEDs) in automotive applications.

Design/methodology/approach
– Ar, O2 and O2→Ar plasma treatments were applied to LED chip bond pad prior to wire bonding process with different treatment durations. Various surface characterization methods and contact angle measurement were then used to characterize the surface properties of these chip bond pads. To validate the improvements of Ar, O2 and O2→Ar plasma treatments to the wire bond interfacial adhesion, the chip bond pads were wire bonded and examined with a ball shear test. Moreover, the contact resistance of the wire bond interfaces was also measured by using four-point probe electrical measurements to complement the interfacial adhesion validation.

Findings
– Surface characterization results show that O2→Ar plasma treatment was able to remove the contaminant while maintaining relatively low oxygen impurity content on the bond pad surface after the treatment and was more effective as compared with the O2 and Ar plasma treatments. However, O2→Ar plasma treatment also simultaneously reduced high-polarity bonds on the chip bond pad, leading to a lower surface free energy than that with the O2 plasma treatment. Ball shear test and contact resistance results showed that wire bond interfacial adhesion improvement after the O2→Ar plasma treatment is lower than that with the O2 plasma treatment, although it has the highest efficiency in surface contaminant removal.

Originality/value
– To resolve “lifted ball bond” issue, optimization of plasma gas composition ratios and parameters for respective Ar and O2 plasma treatments has been widely reported in many literatures; however, the O2→Ar plasma treatment is still rarely focused. Moreover, the observation that wire bond interfacial adhesion improvement after O2→Ar plasma treatment is lower than that with the O2 plasma treatment although it has the highest efficiency in surface contaminant removal also has not been reported on similar studies elsewhere.
Recent advances in mechanical properties of anisotropic conductive adhesive film for microelectronic packaging
Authors: Gao Lilan , Gao Hong , Chen Xu 
Published: August 2015

Purpose– This review paper aims to provide a better understanding of formulation and processing of anisotropic conductive adhesive film (ACF) material and to summarize the significant research and development work for the mechanical properties of ACF material and joints, which helps to the development and application of ACF joints with better reliability in microelectronic packaging systems.Design/methodology/approach– The ACF material was cured at high temperature of 190°C, and the cured ACF was tested by conducting the tensile experiments with uniaxial and cyclic loads. The ACF joint was obtained with process of pre-bonding and final bonding. The impact tests and shear tests of ACF joints were completed with different aging conditions such as high temperature, thermal cycling and hygrothermal aging.Findings– The cured ACF exhibited unique time-, temperature- and loading rate-dependent behaviors and a strong memory of loading history. Prior stress cycling with higher mean stress or stress amplitude restrained the ratcheting strain in subsequent cycling with lower mean stress or stress amplitude. The impact strength and adhesive strength of ACF joints increased with increase of bonding temperature, but they decreased with increase of environment temperature. The adhesive strength and life of ACF joints decreased with hygrothermal aging, whereas increased firstly and then decreased with thermal cycling.Originality/value– This study is to review the recent investigations on the mechanical properties of ACF material and joints in microelectronic packaging applications.