bluuebunny/crossref_metadata_2025_split huggingface dataset:
Host Gut Motility and Bacterial Competition Drive Instability in a Model Intestinal Microbiota
Authors: Wiles Travis J. , Jemielita Matthew L. , Baker Ryan P. , Schlomann Brandon H. , Logan Savannah L. , Ganz Julia , Melancon Ellie , Eisen Judith S. , Guillemin Karen , Parthasarathy Raghuveer 
Published: May 2016

AbstractThe gut microbiota is a complex consortium of microorganisms with the ability to influence important aspects of host health and development. Harnessing this ‘microbial organ’ for biomedical applications requires clarifying the degree to which host and bacterial factors act alone or in combination to govern the stability of specific lineages. To address this we combined bacteriological manipulation and light sheet fluorescence microscopy to monitor the dynamics of a defined two-species microbiota within the vertebrate gut. We observed that the interplay between each population and the gut environment produced distinct spatiotemporal patterns. Consequently, one species dominates while the other experiences dramatic collapses that are well fit by a stochastic mathematical model. Modeling revealed that bacterial competition could only partially explain the observed phenomena, suggesting that a host factor is also important in shaping the community. We hypothesized the host determinant to be gut motility, and tested this mechanism by measuring colonization in hosts with enteric nervous system dysfunction due to mutation in the Hirschsprung disease locusret. In mutant hosts we found reduced gut motility and, confirming our hypothesis, robust coexistence of both bacterial species. This study provides evidence that host-mediated spatial structuring and stochastic perturbation of communities along with bacterial competition drives population dynamics within the gut. In addition, this work highlights the capacity of the enteric nervous system to affect stability of gut microbiota constituents, demonstrating that the ‘gut-brain axis’ is bidirectional. Ultimately, these findings will help inform disease mitigation strategies focused on engineering the intestinal ecosystem.
Quantification of telomere features in tumor tissue sections by an automated 3D imaging-based workflow
Authors: Gunkel Manuel , Chung Inn , Wörz Stefan , Deeg Katharina I. , Simon Ronald , Sauter Guido , Jones David T.W. , Korshunov Andrey , Rohr Karl , Erfle Holger , Rippe Karsten 
Published: May 2016

AbstractThe microscopic analysis of telomere features provides a wealth of information on the mechanism by which tumor cells maintain their unlimited proliferative potential. Accordingly, the analysis of telomeres in tissue sections of patient tumor samples provides can be exploited to obtain diagnostic information and to define tumor subgroups. In many instances, however, analysis of the image data is conducted by manual inspection of 2D images at relatively low resolution for only a small part of the sample. As the telomere feature signal distribution is frequently heterogeneous, this approach is prone to a biased selection of the information present in the image and lacks subcellular details. Here we address these issues by using an automated high-resolution imaging and analysis workflow that quantifies individual telomere features on tissue sections for a large number of cells. The approach is particularly suited to assess telomere heterogeneity and low abundant cellular sub-populations with distinct telomere characteristics in a reproducible manner. It comprises the integration of multi-color fluorescence in situ hybridization, immunofluorescence and DNA staining with targeted automated 3D fluorescence microscopy and image analysis. We apply our method to telomeres in glioblastoma and prostate cancer samples, and describe how the imaging data can be used to derive statistically reliable information on telomere length distribution or colocalization with PML nuclear bodies. We anticipate that relating this approach to clinical outcome data will prove to be valuable for pretherapeutic patient stratification.Abbreviations3D-TIM3D targeted imagingALTalternative lengthening of telomeresAPBALT-associated PML-NBCLSMconfocal laser scanning fluorescence microscopyECTRextrachromosomal telomeric repeatFFPEformalin-fixed, paraffin-embeddedFISHfluorescence in situ hybridizationIFImmunofluorescencepedGBMpediatric glioblastomaPMLpromyelocytic leukemiaPML-NBPML nuclear bodyPNApeptide nucleic acidROIregion of interestTMAtissue microarrayTMMtelomere maintenance mechanismSMLMsingle molecule localization microscopy
Competition and bank efficiency in emerging markets: empirical evidence from Ghana
Authors: Alhassan Abdul Latif , Ohene-Asare Kwaku 
Published: May 2016

Purpose– The purpose of this paper is to examine the relationship between competition and efficiency in the Ghanaian banking industry.Design/methodology/approach– Data on 26 banks from 2004 to 2011 is used to estimate technical and cost-efficiency scores by the data envelopment analysis while the Boone indicator is employed to proxy for competition. Controlling for bank size, lending, income diversification, tangibility, leverage and profitability, ordinary least squares, instrumental variables and fixed effects estimations are used to estimate the panel regression model. The authors also apply the growth convergence theory to examine the existence of efficiency convergence.Findings– The results points to improvements in cost efficiency (CE) and competition within the banking industry. From the empirical estimations, the findings suggest that competition exerts a positive influence on CE. The authors also find evidence of convergence in both technical and CE.Research limitations/implications– The study recommends that efforts at improving competitiveness of the banking industry will translate into lower interest rate spread through improved CE. This will ultimately improve access to bank credit and impact positively on economic growth. Future studies could also examine productivity changes and scale economies in the banking industry.Originality/value– To the authors best knowledge, this is the first study to apply the Boone (2001) indicator in assessing the competitiveness of the Ghanaian banking industry. This is also the first study to examine efficiency convergence within the banking industry in Ghana.
Fiscal variables and growth convergence in the ECOWAS
Authors: Magazzino Cosimo 
Published: May 2016

Purpose– The purpose of this paper is to assess the relationship among fiscal variables (net lending, government expenditure and revenue) and economic growth in Sub-Saharan African countries.Design/methodology/approach– Using yearly data for the period between 1980 and 2011 in 15 Economic Communities Of West African States (ECOWAS) countries, the relationship among fiscal variables, economic growth and trade is investigated, through various econometric techniques.Findings– Government expenditure and revenue show pro-cyclical effects in West African Economic and Monetary Union (WAEMU) and ECOWAS countries, while fiscal balance has a pro-cyclical nature for WAEMU during the years 1999-2011. Moreover, a weak long-run relationship between government expenditure and revenue emerge, but only in the case of West African Monetary Zone (WAMZ) countries. Granger causality analysis showed mixed results for WAEMU countries, while for four out of six WAMZ countries (Gambia, Liberia, Nigeria, and Sierra Leone) the “tax-and-spend” hypothesis holds, since government revenue would drive the expenditure. Finally, in the last three decades, cyclical component of economic growth has reduced its fluctuations, both for WAEMU and WAMZ member States.Originality/value– This is the first study on the effects of fiscal policies in the ECOWAS countries.
The role of local financial market on economic growth
Authors: Aregbeshola Rafiu Adewale 
Published: May 2016

Purpose
– Capital market development has been identified as one of the critical underpinnings of economic growth, in the developed but more essentially in the developing economies. Evidence abounds on the virtues of adequately spanned capital markets to provide requisite capital needed to fund investment activities as well as infrastructural developments. Although, foreign capital may be sourced to supplement inadequate local capital base, the associated costs (both logistics and supervisory) are generally daring to consider as convenient alternatives. Various studies have examined the role of local financial market development on economic growth, but none have strictly generated a combined focus on the three major African groupings – the Southern, the Western and the Northern African regions. In addition, there is no documented study that has compared the economic performance of each of these three major economic groupings in Africa. The purpose of this paper is to fill these voids.

Design/methodology/approach
– Various econometric techniques that include descriptive statistics, unit root tests, dynamic panel estimations and Granger causality tests.

Findings
– Using data generated from the African development indicators between 1980 and 2012 in contemporary econometric estimations, this study finds that local financial markets play crucial roles in economic development of each of these groupings, albeit in varying magnitude. The study also observes that local financial market plays very little role in the overall economic development of the three groupings when interacted.

Research limitations/implications
– A limited dataset, which reduces the time span as well as the number of countries covered in the study. A wider coverage may have altered the result generated, especially for the pooled estimation.

Practical implications
– That African countries should develop local financial markets in order to improve their level of economic growth.

Social implications
– Low rate of economic development has created a lot of social stress in Africa. Further, the fact that African leaders have largely not been able to grow their national economies in a meaningful and sustainable manner further unnerves skittish entrepreneurial underdevelopment on the continent, thereby exacerbates incidence and prevalence of poverty, and consequent social uprisings on a number of occasions.

Originality/value
– This study finds that financial market plays an important role on economic growth, whereas the effects are lower in the Southern African region. More specifically, the effects of financial market development on economic growth are stronger in North and West Africa than in Southern African regions. Given that Southern Africa financial market is more developed than the other two regions, this finding buttresses the fact that financial market development is significantly more important as a growth-driver in less developed financial markets than in developed ones.
Time your investment on the Ghana Stock Exchange (GSE)
Authors: Mensah Lord , Bokpin Godfred Alufar , Owusu-Antwi George 
Published: May 2016

Purpose
– The purpose of this paper is to investigate the day of the week effect on the Ghana Stock Exchange (GSE) by using the GSE all-share index from November 1990 to August 2012. The presence of the day of the week effect has been reported on several markets.

Design/methodology/approach
– The study utilizes one-sample t-test, dummy variable regression, autoregressive and generalized autoregressive conditional heteroskedastic models to investigate whether day of the week effect exist on the GSE.

Findings
– The study reveals the presence of day of the week effect on the GSE, specifically, highest returns on Tuesday and lowest on Thursday. Monday, Wednesday and Friday also record significant positive returns, however, the significance returns is captured by a strong auto-regression in the returns. Therefore, investors may not have the opportunity to increase their returns by timing their investments. Further, the significance of the anomalies is not robust across time since different sub periods with different trading days per week shows different results.

Originality/value
– The study provides additional evidence on the day of the week effect by using utilizing frontier market data.
In search of structural change surplus and perpetual growth in Ethiopia
Authors: Eshete Zerayehu Sime , Kimuyu Peter Kiko 
Published: May 2016

Purpose
– The Ethiopian economy is characterized by erratic and poor performance with negative growth rates, seven times over the period 1981-2010. This trapped per capita income at 358 USD in 2010 staying far away from middle-income country status. A lot of unsolved debates regarding perpetual growth, structural change and sectoral allocation of resource emerged overtime. The purpose of this paper is to examine the alternative effects of induced sectoral total factor productivity and makes comparisons of various sectoral growth options.

Design/methodology/approach
– This study uses a recursive dynamic computable general equilibrium model based on neoclassical-structuralist thought. It also calibrates coefficients that capture the impacts of openness, imported capital and liberalization on sectoral total factor productivity growth using a model of vector auto-regressive with exogenous variables.

Findings
– Future economic growth rate is expected to grow at a declining trend and to be dominated by the service sector. If it keeps growing on the current path it will expose the economy to a severe structural change burden problem. Openness induced agricultural total factor productivity highly improves the welfare of households while imported capital goods induced industrial total factor productivity is also better in fostering structural change of the economy. The broad-based growth option that combines the induced total factor productivity of all sectors also enables the economy to achieve more sustainable growth, rapid structural change and welfare gain at the same time.

Originality/value
– There are intensive and charged debates regarding alternative sectoral growth options. However, the debate does not derive from a rigorous analysis and holistic economy-wide approach. It is rather affiliated with politics. Therefore, the paper is original and investigates these issues meticulously.
Revolving doors: are they valued in the Spanish stock market?
Authors: Farinós Viñas J. Emilio , García Martin C. José , Herrero Piqueras Begoña , Ibáñez Escribano Ana M. 
Published: May 2016

Purpose
The purpose of this paper is to examine the effect of political connections in the value of companies listed on the Spanish stock market.

Design/methodology/approach
The authors study two issues on this topic: the impact on the company value of the appointment as director of an ex-politician through an event study; and the long run stock market performance of companies with political connections. The authors employ a sample of listed firms in the Spanish stock market for which the authors collected data about their political connections. The authors perform the study during a wide period (1996-2011), comprising four legislatures.

Findings
The results show that from the market perspective the value ex-politicians bring to the company outweigh their costs, especially in times of crisis or economic recession.

Originality/value
Given the concern of regulators and legislators to increase transparency and good governance of companies, this paper shed light on the role that politicians play on the company boards and and their contribution to their value.
Persistence in generating and adopting product innovations
Authors: Juliao-Rossi Jorge , Schmutzler Jana 
Published: May 2016

Purpose
The purpose of this paper is to test the existence of true persistence in the generation and adoption of product innovations in the context of a developing country.

Design/methodology/approach
A dynamic probit model with random effects is used to test true persistence relying on a panel data set constructed from three waves of the Colombian innovation survey (Encuesta de Desarrollo e Innvovación Tecnológica) covering the time span from 2003 to 2008.

Findings
This paper empirically shows the existence of true innovation persistence for two of the three types of product innovation studied: the adoption of product innovation that is new to the firm; and the adoption of product innovation that is new to the national market. However, the study could not confirm true persistence in the generation of product innovation.

Originality/value
To the best of our knowledge, this is the first study that systematically tests innovation persistence differentiating between the adoption of innovations that are new to the firm and innovation that is new to the national market. It is also the first study in this research area that uses a dynamic probit model with random effects according to the original specification by Wooldridge (2005).
Project risk planning in high-tech new product development
Authors: Ayala-Cruz Jorge 
Published: May 2016

PurposeThe purpose of this paper is to present the implementation and testing of a modified project risk management framework that integrates PMI’s framework with Monte Carlo simulation to improve the effectiveness in high-tech new product development (NPD) projects.Design/methodology/approachThe modified framework considers three bodies of knowledge: project management, risk management, and Monte Carlo simulation to produce an enhance project risk management framework. Its application is shown through a case study.FindingsUsing the integrated framework in a recent case study project and prior NPD projects measures (as benchmarks), it was shown that it could help to enhance risk responses caused by task durations and costs’ uncertainties. The framework proved to be better than segregated generic best practices and was key in providing insight to the issue of early project risk assessment.Research limitations/implicationsMore experimental replications are required for enhancement effectiveness assertions of the framework, through the application of the framework to similar case studies. Furthermore, this could improve its reliability and soundness.Practical implicationsFuture directions for research could include case and empirical studies that include hypothesis’s testing, and the integration of optimization procedure for improved NPD project’s planning and execution.Originality/valueThis paper outlines a way to close the gap of project risks management planning in NPD’s initiatives. It was motivated by a relatively new tendency in exploring integrated frameworks to deal with complex project risks issues.
Analysis of causes and impact of variation order on educational building projects
Authors: Oyewobi Luqman Oyekunle , Jimoh Richard , Ganiyu Bashir Olanrewaju , Shittu Abdullateef Adewale 
Published: May 2016

Purpose
Construction process is complex and traditionally fragmented; thus, it is almost impossible to have a project completed without changes to the original plan or the construction process. The purpose of this study is to identify and examine the causes of variation orders, ascertain their effects and establish the cost and time performance implication as a result of variation orders.

Design/methodology/approach
This study obtained information from 90 construction stakeholders on 30 completed educational building projects to ascertain the causes and effects of variation orders on project delivery using questionnaire survey. In addition to this, a pro forma document was designed to obtain the project characteristics, cost and time data from these 30 completed educational building projects. Factor analysis was used to categorise the causes of variation orders, while severity index was used to examine their effects on project delivery. The hypothesised statement was tested using paired t-statistics to examine whether a statistically significant difference existed between variation orders, cost and time performance of the projects.

Findings
The study identified 13 main factors as causes of variation orders and the results revealed that the most frequent effects of variations were increase in construction costs, time, client dissatisfaction, increase construction project rework and demolition and project abandonment. The results also showed that variation orders had significant effects on both cost and scheduled performance of the educational building projects with average cost and time escalation of 33.95 and 29.45 per cent of the original project cost and time, respectively, for the entire projects studied, while average cost implication of variation orders is 23.79 per cent.

Practical implications
The findings in this study will be of assistance to government agencies and management of public works in higher institutions of learning in managing variations in construction projects. The study will also add to the current literature on the impact of variation orders on educational building projects in developing countries. Finally, it will create the much-needed awareness on the severity and implication of change or variation orders on project delivery.

Originality/value
The study identified and examined the causes of variation orders, ascertained their effects and established the cost and time effects of the causes of variation order on project performance. This will assist project initiators, contractors, consultants and other stakeholders to fully appreciate and understand the significant effects of variation orders on project performance.
Front and backstage in the workplace
Authors: Ekstrand Mari , Damman Sigrid 
Published: May 2016

PurposeThe ability of employees to handle work-related demands, structure their own work and manage workflow is highly important in today’s complex organisations. This paper aims to explore the impact of the office environment on employees’ ability to control interaction, structure their own work processes and handle work-related demands. The focus is on the influence of the physical premises, especially on how work within private, privileged and public work zones may affect perceptions of, and possibilities to control, customer interactions and other work-related demands.Design/methodology/approachThe paper is based on a qualitative case study of a Norwegian finance corporation. The core method was semi-structured interviews, carried out with 29 employees and managers. The triangulated research design included observations, field notes, user logs and document analyses.FindingsThe findings indicate that, in a customer-centred work process, separate zones for customer-related work and for internal work provide employees with increased scope to handle work demands and perceive control in their work. Zoning helped structure the workflow and provided employees with new resources in customer interaction and other work tasks.Originality/valueBroadening the focus on environmental control and work-related demands from individual coping to social interaction may provide more insight into factors influencing work processes and employee well-being in emerging workplace concepts.