bluuebunny/crossref_metadata_2025 huggingface dataset:
Targeting of NF-κB to Dendritic Spines is Required for Synaptic Signaling and Spine Development
Authors: Dresselhaus Erica C. , Boersma Matthew C.H. , Meffert Mollie K.
Published: March 2018

Long-term forms of brain plasticity share a requirement for changes in gene expression induced by neuronal activity. Mechanisms that determine how the distinct and overlapping functions of multiple activity-responsive transcription factors, including nuclear factor kappa B (NF-κB), give rise to stimulus-appropriate neuronal responses remain unclear. We report that the p65/RelA subunit of NF-κB confers subcellular enrichment at neuronal dendritic spines and engineer a p65 mutant that lacks spine-enrichment (ΔSEp65) but retains inherent transcriptional activity equivalent to wild-type p65. Wild-type p65 or ΔSEp65 both rescue NF-κB-dependent gene expression in p65-deficient murine hippocampal neurons responding to diffuse (PMA/ionomycin) stimulation. In contrast, neurons lacking spine-enriched NF-κB are selectively impaired in NF-κB-dependent gene expression induced by elevated excitatory synaptic stimulation (bicuculline or glycine). We used the setting of excitatory synaptic activity during development that produces NF-κB-dependent growth of dendritic spines to test physiological function of spine-enriched NF-κB in an activity-dependent response. Expression of wild-type p65, but not ΔSEp65, is capable of rescuing spine density to normal levels in p65-deficient pyramidal neurons. Collectively, these data reveal that spatial localization in dendritic spines contributes unique capacities to the NF-κB transcription factor in synaptic activity-dependent responses.

SIGNIFICANCE STATEMENT

Extensive research has established a model in which the regulation of neuronal gene expression enables enduring forms of plasticity and learning. However, mechanisms imparting stimulus-specificity to gene regulation, insuring biologically appropriate responses, remain incompletely understood. NF-κB is a potent transcription factor with evolutionarily-conserved functions in learning and the growth of excitatory synaptic contacts. Neuronal NF-κB is localized in both synapse and somatic compartments, but whether the synaptic pool of NF-κB has discrete functions is unknown. This study reveals that NF-κB enriched in dendritic spines (the postsynaptic sites of excitatory contacts) is selectively required for NF-κB activation by synaptic stimulation and normal dendritic spine development. These results support spatial localization at synapses as a key variable mediating selective stimulus-response coupling.
Mathematical modelling of molecular heterogeneity identifies novel markers and subpopulations in complex tumors
Authors: Chen Lulu , Wang Niya , Clarke Robert , Zhang Zhen , Wang Yue
Published: March 2018

Intratumor heterogeneity, as both a major confounding factor and an underexploited information source, is widely implicated as a key driver of drug resistance. While a handful of reports have demonstrated the potential of supervised methods to deconvolute intratumor heterogeneity, these approaches require a priori information on the marker genes or composition of known subpopulations. To address the critical problem of the absence of validated marker genes for many (including novel) subpopulations, we developed convex analysis of mixtures (CAM), a fully unsupervised deconvolution method, for identifying marker genes and subpopulations directly from original mixed molecular expressions.
Nonlinear functional responses and ecological pleiotropy alter the strength of disruptive selection in consumers
Authors: Coblentz Kyle E.
Published: March 2018

Much of the theory on disruptive selection has focused on selection in generalist consumers caused by ecological opportunity through the availability of alternative resources and intraspecific competition for those resources. This theory, however, makes several ecologically unrealistic assumptions. First, this theory assumes that consumers have a linear, resource-dependent functional response, ignoring well-documented effects of resource handling times and consumer dependence. Second, this theory assumes that the trait under selection only influences the percapita attack rates of the consumer, ignoring other effects of the trait that may influence feeding rates and hence fitness. Here, I develop a one consumer-two resource model to investigate how nonlinear functional responses and ecological pleiotropy (traits that have multiple simultaneous ecological effects) influence the strength of disruptive selection. I find that handling times and interference among consumers are capable of altering disruptive selection by changing feeding rates differentially across consumer phenotypes. In particular, handling times cause a decrease in the strength of disruptive selection while the effects of interference depend on the mechanism through which interference occurs. The effects of handling times and interference, however, are dependent on whether and how ecological pleiotropy causes correlations between handling times or interference rates and attack rates. Overall, my results suggest that features defining the functional responses of consumers and the relationships among those features determine the likelihood and strength of disruptive selection. In particular, disruptive selection should be strongest in generalist populations composed of individual diet specialists who experience lower handling times and interference rates on the resources for which their attack rates are highest.
Population dynamics of choice representation in dorsal premotor and primary motor cortex
Authors: Peixoto Diogo , Kiani Roozbeh , Chandrasekaran Chandramouli , Ryu Stephen I. , Shenoy Krishna V. , Newsome William T.
Published: March 2018

Studies in multiple species have revealed the existence of neural signals that lawfully co-vary with different aspects of the decision-making process, including choice, sensory evidence that supports the choice, and reaction time. These signals, often interpreted as the representation of a decision variable (DV), have been identified in several motor preparation circuits and provide insight about mechanisms underlying the decision-making process. However, single-trial dynamics of this process or its representation at the neural population level remain poorly understood. Here, we examine the representation of the DV in simultaneously recorded neural populations of dorsal premotor (PMd) and primary motor (M1) cortices of monkeys performing a random dots direction discrimination task with arm movements as the behavioral report. We show that single-trial DVs covary with stimulus difficulty in both areas but are stronger and appear earlier in PMd compared to M1 when the stimulus duration is fixed and predictable. When temporal uncertainty is introduced by making the stimulus duration variable, single-trial DV dynamics are accelerated across the board and the two areas become largely indistinguishable throughout the entire trial. These effects are not trivially explained by the faster emergence of motor kinematic signals in PMd and M1. All key aspects of the data were replicated by a computational model that relies on progressive recruitment of units with stable choice-related modulation of neural population activity. In contrast with several recent results in rodents, decision signals in PMd and M1 are not carried by short sequences of activity in non-overlapping groups of neurons but are instead distributed across many neurons, which once recruited, represent the decision stably during individual behavioral epochs of the trial.
Glutamatergic facilitation of neural responses in MT enhances motion perception in humans
Authors: Schallmo Michael-Paul , Millin Rachel , Kale Alex M. , Kolodny Tamar , Edden Richard A.E. , Bernier Raphael A. , Murray Scott O.
Published: March 2018

There is large individual variability in human neural responses and perceptual abilities. The factors that give rise to these individual differences, however, remain largely unknown. To examine these factors, we separately measured fMRI responses to moving gratings in the motion-selective region MT, and perceptual duration thresholds for motion direction discrimination within the same group of male and female subjects. Further, we acquired MR spectroscopy data that allowed us to quantify an index of neurotransmitter levels in the region surrounding MT. We show that individual differences in the Glx (glutamate + glutamine) signal in the MT region are associated with both higher fMRI responses and improved psychophysical task performance. Our results suggest that individual differences in baseline levels of glutamate within MT contribute to motion perception by increasing neural responses in this region.

Significance

What factors govern the relationship between neural activity and behavior? Our results suggest that one such factor is the level of glutamate, an excitatory neurotransmitter, within a particular region of cortex. By measuring an index of glutamate in vivo using magnetic resonance spectroscopy, we show that human subjects with more glutamate in the visual motion area known as MT also have larger fMRI responses (an index of neural activity) in this region. Further, people with more glutamate in MT can accurately perceive moving images presented more briefly within a behavioral task. Our findings point to an important role for glutamate levels in determining the relationship between neural responses and behavior during visual motion perception.
Switch-like activation of Bruton’s tyrosine kinase by membrane-mediated dimerization
Authors: Chung Jean K. , Nocka Laura M. , Wang Qi , Kadlecek Theresa A. , Weiss Arthur , Kuriyan John , Groves Jay T.
Published: March 2018

The transformation of molecular binding events into cellular decisions is the basis of most biological signal transduction. A fundamental challenge faced by these systems is that protein-ligand chemical affinities alone generally result in poor sensitivity to ligand concentration, endangering the system to error. Here, we examine the lipid-binding pleckstrin homology and Tec homology (PH-TH) module of Bruton’s tyrosine kinase (Btk) Using fluorescence correlation spectroscopy (FCS) and membrane-binding kinetic measurements, we identify a self-contained phosphatidylinositol (3,4,5)-trisphosphate (PIP3) sensing mechanism that achieves switch-like sensitivity to PIP3 levels, surpassing the intrinsic affinity discrimination of PIP3:PH binding. This mechanism employs multiple PIP3 binding as well as dimerization of Btk on the membrane surface. Mutational studies in live cells confirm that this mechanism is critical for activation of Btk in vivo. These results demonstrate how a single protein module can institute a minimalist coincidence detection mechanism to achieve high-precision discrimination of ligand concentration.
Voltage- and Branch-specific Climbing Fiber Responses in Purkinje Cells
Authors: Zang Yunliang , Dieudonné Stéphane , De Schutter Erik
Published: March 2018

Climbing fibers (CFs) provide instructive signals driving cerebellar learning. However, conflicting experimental studies have been reported about the reliability of CF mediated Ca2+ influx in Purkinje cell (PC) distal dendrites. Mechanisms causing the wide variation in duration and spikelet numbers of complex spikes (CSs) have not been explored systematically. Using a new experimentally validated PC model, we describe the full range of modifiability of CF responses to explain the experimental data and make new predictions. We find voltage state gates the initiation and propagation of dendritic spikes. PC dendrites exhibit inhomogeneous excitability with individual branches as computational units for CF input. Somatic CSs are regulated by voltage state, CF activation phase and instantaneous CF firing rate. Concurrent synaptic inputs can affect CSs by modulating dendritic responses in a spatially precise way. These voltage- and branch-specific CF responses will increase dendritic computational capacity and give PCs an active role in integrating CF signals.
Structures reveal opening of the store-operated calcium channel Orai
Authors: Hou Xiaowei , Burstein Shana R. , Long Stephen B.
Published: March 2018

The store-operated calcium (Ca2+) channel Orai governs Ca2+ influx through the plasma membrane of many non-excitable cells in metazoans. The channel opens in response to depletion of Ca2+ within the endoplasmic reticulum (ER). Loss- and gain-of-function mutants of Orai cause disease. Our previous work revealed the structure of Orai with a closed pore. Here, using a gain-of-function mutation that constitutively activates the channel, we present an X-ray structure of Drosophila melanogaster Orai in an open conformation. Well-defined electron density maps reveal that the open pore is dramatically dilated on its cytosolic side in comparison to the slender closed pore. Cations and anions bind in different regions of the open pore, informing mechanisms for ion permeation and the exquisite selectivity of the channel for Ca2+. Opening of the pore requires the release of cytosolic latches. Together with additional X-ray structures of an unlatched-but-closed intermediate, we propose a sequence for store-operated activation.
Axonal transport and active zone proteins regulate volume transmitting dopaminergic synapse formation
Authors: Lipton David M. , Maeder Celine I. , Shen Kang
Published: March 2018

At a typical synapse, the precise juxtaposition between the active zone and postsynaptic receptors ensures local and precise neurotransmitter release and detection. Dopamine neurons release neurotransmitter more diffusely using volume-transmission, where precise pre- and post-synaptic alignment is lacking. It is unknown whether Dopaminergic presynaptic terminals have typical active zone structures and how they develop. Here we show that presynaptic terminals of the C. elegans dopaminergic neuron PDE contain bona fide AZ proteins, including SYD-2/Liprin-ʡ, ELKS-1, UNC-10/RIM and CLA-1/Piccolo. During development, synaptic vesicles (SVs) and active zone proteins (AZs) coalesce within minutes behind the advancing growth cone. Precise regulation of UNC-104/Kinesin-3-mediated SV transport through kinesin autoinhibition is required to pause transported SVs at synapses. SYD-1 and SYD-2 recruit and cluster the transiting SVs, while ELKS-1 aggregates through a distinct mechanism.
A barcoding approach to phylogenetic classification of Aedini mosquitoes (Aedes, Ochlerotatus)
Authors: Glass H. , Carroll E. , Curley D. , Kienzle H. , Yee D. A. , Vamosi S. M.
Published: March 2018

Traditionally, entomologists have used morphological characteristics for mosquito taxonomy and systematics. However, this approach does not take into consideration the genetic relatedness of species. In 2000, the Aedes genus of mosquitoes in the tribe Aedini was split into two genera (Aedes and Ochlerotatus), thereby elevating Ochlerotatus from subgenus to genus rank, strictly based on morphology of adults. Herein, we use the genetic barcoding marker COI to generate a phylogeny of 65 species of Aedes, Ochlerotatus, and Anopheles outgroup from almost 900 sequences downloaded from BOLD systems. Our results reveal evidence of non-random, but polyphyletic clustering of Aedes and Ochlerotatus species, with a monophyletic outgroup. We do find support for the validity of Ochlerotatus as an evolutionary unit, although we find insufficient evidence to support its retention as a genus. We suggest that mosquito phylogenetic analyses incorporate a greater number of genetic markers to help clarify our understanding of Aedini species classifications, but caution that recent assessments based solely on morphology may be insufficient.
Systematic Optimization of Whole Plant Carbon Nitrogen Interaction (WACNI) to Support Crop Design for Greater Yield
Authors: Chang Tian-Gen , Zhu Xin-Guang
Published: March 2018

On the face of the rapid advances in genome editing technology and greatly expanded knowledge on plant genome and genes, there is a strong demand to develop an effective tool to guide designing crops for higher yields. Here we developed a highly mechanistic model of Whole plAnt Carbon Nitrogen Interaction (WACNI), which predicts crop yield based on major metabolic and biophysical processes in source, sink and transport tissues. WACNI accurately predicted the yield responses of so far reported source, sink and transport related genetic manipulations on rice grain yields. Systematic sensitivity analysis with WACNI was used to classify the source, sink and transport related molecular processes into four categories, i.e. universal yield enhancers, universal yield inhibitors, conditional yield enhancers and weak yield regulators. Simulations using WACNI further show that even without a major change in leaf photosynthetic properties, 54.6% to 73% grain yield increase can be potentially achieved by optimizing these molecular processes during the rice grain filling period while simply combining all the ‘superior’ molecular modules together cannot achieve the optimal yield level. A common macroscopic feature in all these designed high-yield lines is that they all show ‘a sustained and steady growth of grain sink’, which might be used as a generic selection criteria in high-yield rice breeding. Overall, WACNI can serve as a tool to facilitate plant source sink interaction research and guide future crops breeding by design.

One sentence summary

A mechanistic model of source, sink flow model is developed and used to demonstrate that optimization of the whole plant carbon nitrogen metabolism can dramatically increase crop yield potential.
Optimum Levenberg–Marquardt constant determination for nonlinear least-squares
Authors: Coelho Alan Anthony
Published: March 2018

A new method for determining an approximate optimum value for the Levenberg–Marquardt constant has been shown to improve the convergence rate of nonlinear least-squares problems including complex X-ray powder diffraction and single-crystal structural refinements. In the Gauss–Newton method of nonlinear least squares, a lower value for the objective function is occasionally not realized after solving the matrix equationAΔp=b. This situation occurs when either the objective function is at a minimum or theAmatrix is ill conditioned. Invariably the Levenberg–Marquardt method is used, where the matrix equation is reformulated to (A+ λI)Δp=band λ is the Levenberg–Marquardt constant. The values chosen for λ depend on whether the objective function increases or decreases. This paper describes a new method for setting the Levenberg–Marquardt constant, as implemented in the computer programTOPAS-AcademicVersion 7, which in general results in an increased rate of convergence and additionally a lowering of the objective function as a function of starting parameter values. The reduction in computation is problem dependent and ranges from 10% for typical crystallographic refinements to 50% for large refinements. In addition, the method can be applied to general functions including cases where the objective function comprises both the sum of squares and penalties including functions with discontinuities. Of significance is the trivial extra computational effort required in determining λ as well as the simplicity in carrying out the calculation; the latter should allow for easy implementation in refinement programs.
Job embeddedness and employee enactment of innovation-related work behaviours
Authors: Coetzer Alan , Inma Chutarat , Poisat Paul , Redmond Janice , Standing Craig
Published: March 2018

Purpose

In a highly competitive globalised environment, the innovation behaviour of employees plays a key role in the economic viability and competitive advantage of organisations. In this context, developing the understanding of innovation work behaviour is important for the field of individual innovation and this is the focus of the study. The paper aims to discuss this issue.

Design/methodology/approach

Data were collected using a survey from 549 employees in organisations operating in four major business centres in South Africa.

Findings

On-the-job embeddedness was positively and significantly related to innovation behaviours by employees in organisations operating in diverse industries. Consistent with the view that small organisations have a “behavioural” innovation advantage over larger organisations, the size of the organisation moderated the positive relationship between on-the-job embeddedness and innovation behaviours. On-the-job embeddedness was more positively related to innovation behaviours in small organisations than in larger organisations.

Practical implications

Employees who are highly embedded in their jobs (but not necessarily their communities) are more likely to enact innovation behaviours than employees who are not similarly embedded. Human resource management professionals and line managers can potentially foster employee innovation behaviours through adopting strategies aimed at positively influencing the fit, links and sacrifice dimensions of on-the-job embeddedness.

Originality/value

The study contributes to theoretical and empirical expansion of job embeddedness (JE) by examining: how work and non-work forces that attach employees to their organisations influence their propensity to enact innovation behaviours; and how organisation size moderates the relationship between JE and innovation behaviours. The results will help managers who wish to foster innovation.
Workers’ compensation insurance prices: evidence from Portugal
Authors: Garcia Maria Teresa Medeiros , Cortegano Joana Teresa Silva
Published: March 2018

Purpose

The purpose of this paper is to analyse the determinants of workers’ compensation insurance prices in Portugal.

Design/methodology/approach

Multiple regression analysis was used to study the insurance price determinants. The independent variables considered are: payroll, number of employees, and incidence rate. In addition, three categorical variables were used: region, classification of economic activities, and enterprise size. A cross-firm panel data sample from the SABI database of 1,435 firms was considered, over a time horizon from 2010 to 2012. Furthermore, the sample split criterion was the enterprise size.

Findings

As expected, the results suggest that payroll and number of employees are related with workers’ compensation insurance prices. Furthermore, incidence rate, region, type of economic activities, and enterprise size have a positive and significant influence on premiums.

Research limitations/implications

More panel data are needed to allow a greater focus on the impacts of GDP fluctuations and sectoral consolidation on insurance pricing. Further research could also include the impact of capital/reserving cycles, which can be driven both by economic shocks and the competition cycle. It is well known that insurers tend to reduce reserving standards when under pressure, and this can result in inadequate pricing.

Practical implications

The process of workers’ compensation insurance price formation is disentangled. The results suggest that the workers’ compensation insurance premiums behave as expected, especially under periods of economic strain. Therefore, workers’ compensation rate regulation should take this evidence into account, specifically through the establishment of minimum rates, which will protect the insurer, the employer, and the employees alike.

Originality/value

The paper is part of a considerable literature on insurance pricing in workers’ compensation, most of which has centred on private markets in the USA. This paper is the first empirical work that employs private market data for Portugal.
Labor markets, academic performance and school dropout risk: evidence for Spain
Authors: Guio Juan , Choi Álvaro , Escardíbul Josep-Oriol
Published: March 2018

Purpose

The purpose of this paper is to provide a better understanding of the links between labor market conditions and academic performance by disentangling the effects of unemployment. The contribution of this study is, therefore, threefold: first, it provides new evidence on the link between labor market conditions and educational decisions; second, it quantifies separately the two separate effects of unemployment on academic performance at age 15; and third, it analyses heterogeneous effects of the “family” and “local labor market” – proxied through the unemployment rate of the school community – effects.

Design/methodology/approach

The analysis of the impact of unemployment on academic performance is performed through hierarchical linear regressions.

Findings

The results show that academic performance at age 15 is affected by labor market conditions, and, at the same time, previous performance determines future educational decisions. Thus, these results highlight the sensitivity of students’ educational decisions and academic performance to shifts in the labor market.

Practical implications

This suggests that strategies aimed at reducing early school dropout rates should not be restricted solely to the education system. In other words, school failure is not only dependent on schools and, hence, on education policies.

Originality/value

This paper contributes to the existing literature by providing new evidence on the relationship between short-term labor market dynamics and academic performance. More specifically, this paper represents a significant step forward in comparison to the previous literature as it has provided responses to three key questions faced by countries with high unemployment and high early school dropout.
Testing the mediation effect of person-organisation fit on the relationship between talent management and talented employees’ attitudes
Authors: Mensah James Kwame , Bawole Justice Nyigmah
Published: March 2018

Purpose

Previous studies suggested that talent management (TM) is positively related to employee work attitudes. However, a few studies have examined the mechanisms through which TM leads to employee work attitudes. The purpose of this paper is to examine the mediating role of person-organisation (P-O) fit on the relationship between TM and employee’s job satisfaction, and organisational citizenship behaviours (OCBs).

Design/methodology/approach

Using a sample of 232 talented employees from the Ghanaian banking sector, a partial mediation model was outlined and tested using structural equation modelling.

Findings

The results showed that TM had positive relationship with P-O fit, job satisfaction and OCBs. The findings further show that P-O fit had positive relationship between job satisfaction and OCBs and partially mediated the relationship between TM and both job satisfaction, and OCBs.

Research limitations/implications

This study used cross-sectional data; hence, conclusions regarding causality cannot be made. That is, the results must be interpreted as associations rather than causality.

Practical implications

Management should endeavour to use TM to help align talented employee’s competences, values and goals to those of their organisation.

Originality/value

This study contributed to the TM literature by providing a stronger and more plausible explanation of the relationship between TM and talented employees’ outcomes.
The role of non-formal lifelong learning at different points in the business cycle
Authors: Corrales-Herrero Helena , Rodríguez-Prado Beatriz
Published: March 2018

Purpose

Despite the widely recognised importance of lifelong learning, there are mixed results on its causal economic impact. The purpose of this paper is to investigate how economic conditions change the composition of participants in non-formal lifelong learning and whether the business cycle is relevant for the impact of non-formal lifelong learning on employability.

Design/methodology/approach

Non-linear decomposition techniques and matching estimators based on multidimensional covariates are applied to the Spanish sample of the European Adult Education Survey. The analysis controls for background, human capital and personal traits and draws a distinction between unemployed and employed workers.

Findings

The results show major differences in the volume and composition of participants before and during the Great Recession. In addition, there is a business cycle dependence of the effectiveness of non-formal lifelong learning that varies with the individual labour market situation. While lifelong learning proves more effective for the unemployed in recessions, for the employed the impact is greater in expansions.

Originality/value

The paper provides new evidence on the scant results of the moderating effect of the business cycle on the impact of lifelong learning. The analysis is not restricted to training implemented within public programmes, but rather extends to any kind of non-formal lifelong learning undertaken by unemployed and employed workers. In this sense, the analysis provides information about the optimal moment to invest in lifelong learning from both the policymaker and individual as well as firm perspective.
Human resources disclosures by African and Caribbean companies
Authors: Bowrin Anthony Roger
Published: March 2018

Purpose

The purpose of this paper is to examine the extent to which economically significant Caribbean and African firms provide human resources disclosures (HRD), and the factors related to their disclosure practices. It is motivated by the dearth of studies of HRD among firms in developing countries.

Design/methodology/approach

All companies with common shares listed on the main tier of the major stock exchanges in each country examined on December 31, 2013 as well as selected state enterprises were included in the study if their annual report, sustainability report or integrated report was available online. HRD was measured using an unweighted 174-item disclosure index. The research hypotheses were examined using multiple-regression analysis.

Findings

The level of HRD in the Caribbean and Southern Africa was relatively low (M=33.7 percent, SD=25.3 percent). The amount of HRD was related to organizational culture, firm size, industry affiliation, national governance environment and foreign influence. Geographical region, gender diversity and director independence were not statistically related to the amount of HRD.

Practical implications

Caribbean and African governments may need to implement incentives for economically significant companies to participate in targeted human resources (HR) development initiatives, to provide more comprehensive HR disclosures and incorporate HR consideration in their strategic decision making.

Originality/value

This is one of the first studies to compare the amount and determinants of HRD by economically significant Caribbean and African companies.
The effect of political connections on companies’ performance and value
Authors: Maaloul Anis , Chakroun Raïda , Yahyaoui Sabrine
Published: March 2018

Purpose

The purpose of this paper is to examine the effect of companies’ political connections (PCs) on their financial and stock performance, as well as on their market values.

Design/methodology/approach

A sample of non-financial companies listed on the Tunis Stock Exchange (TSE) between 2012 and 2014 was used. The accounting and financial data of these companies were obtained from their financial statements, whereas data on PCs of their officers and directors were collected manually from various sources. Correlation and multivariate regression analyses were performed to test the hypothesis of this research.

Findings

The results showed that PCs improve companies’ performance and value. These results could be explained, on the one hand, by the benefits and favors that companies can get from their political ties and, on the other hand, by investors’ tendency to invest in politically connected companies to benefit from these advantages.

Research limitations/implications

The limited number of non-financial companies listed on the TSE is a limit for this research.

Practical implications

The results show that investment in companies which are politically inter-connected may be beneficial for investors, and especially for small minority shareholders.

Social implications

The results confirm that political links are essential for business success in emerging economies, such as Tunisia. However, the positive link between politics and business might highlight the issue of corruption after the revolution.

Originality/value

To the best of the authors’ knowledge, this is the first study to examine the effect of PCs on the performance and value of Tunisian companies after the 2011 revolution.
Reading beyond the lines: themes and cultural values in corporate leaders’ communication
Authors: Ngai Cindy Sing-Bik , Singh Rita Gill
Published: March 2018

Purpose

The unprecedented economic development and increase in the number of global corporations in the Greater China region, comprising the Chinese mainland, Taiwan and Hong Kong, have led to more emphasis on corporate leader-stakeholder communication. Bilingual web-based messages posted on corporate websites, which aim to strategically cultivate positive relationships between leaders and stakeholders, have emerged as a primary mode of communication for Chinese corporations. However, a research study investigating the prominent themes and underlying cultural values depicted in leaders’ messages intended for different groups of stakeholders is lacking. Therefore, the purpose of this paper is to investigate the themes and cultural values expressed through corporate leaders’ web-based messages in a non-western context.

Design/methodology/approach

Using an inductive approach, open coding and a categorization system, this study analyzed the web-based messages of leading corporations with WordSmith 6.0.

Findings

Six prominent themes in leaders’ communication were identified. These themes included, in order of importance: company development, operating philosophy, company profile, business environment, performance, and products and services. It was found that leaders strategically selected certain themes such as focusing on progress and the business environment but omitted others depending on how they wanted to strategically influence their stakeholders’ attitudes. Differences between the cultural values depicted in Chinese and the corresponding English messages could be attributed to leaders’ cultural adaptation of the messages intended for non-domestic stakeholders.

Originality/value

Since this study provides insights into the major themes preferred by leaders of corporations operating in Greater China, it will enable existing stakeholders to understand the main business focus of leaders and offer leaders more information about commonly accepted themes. These possibilities for enhanced knowledge on the part of stakeholders and business leaders, in turn, may potentially increase academic appreciation of the complexities involved in corporate communication. It also informs stakeholders about the variations in the values reflected in the English and Chinese messages of leaders, and, therefore, has a potential to offer value to academics and practitioners.
US Securities and Exchange Commission’s announcement of chief of Foreign Corrupt Practices Act unit signals possible anti-bribery enforcement focus on non-United States issuers
Authors: Sanders James L. , Bahr Kyle , Chan Calvin , Hewetson Charles
Published: March 2018

Purpose

This paper explains how recent statements by the US Securities and Exchange Commission’s (SEC’s) leadership – including the new Chief of the SEC’s Foreign Corrupt Practices Act (FCPA) Unit – signal the American regulator’s intent to “level the playing field” by stepping up its investigations and enforcement of companies worldwide and what non-US issuers can do to prepare.

Design/methodology/approach

Uses information included in the announcement naming Charles E. Cain as Chief of the SEC’s specialized FCPA Unit to lay out an argument that the Unit’s priorities may focus more on non-US companies than US companies.

Findings

Based on past statements and written accounts made by Mr Cain, and with the tacit support of other senior SEC officials, it can be assumed that non-US companies will experience additional scrutiny from the SEC, in the name of leveling the playing field. Furthermore, it can be assumed that the SEC will place additional pressure on anti-corruption regimes in other international jurisdictions to do their part in combatting corruption.

Originality/value

This paper is of value to personnel within non-US issuers who are responsible for creating and enforcing their organization’s anti-bribery or anti-corruption policies and internal controls. It is also of value to legal counsel interested in developing an understanding of the current priorities of the SEC as far as the FCPA is concerned.
Communicating corporate social responsibility (CSR) in the coffee industry
Authors: Bradley Oliver James , Botchway Gloria Oforiwaa
Published: March 2018

Purpose

The purpose of this paper is to identify the sustainability indicators disclosed by ten British Coffee Association corporate members in their sustainability reporting and examine whether the indicators correspond to the sustainability challenges faced by the coffee industry, as identified in the literature.

Design/methodology/approach

A normative account of sustainability challenges was developed based on a review of extant literature. A content analysis of the sustainability reports and/or Webpages of the companies was conducted to identify quantitative and qualitative sustainability indicators. Frequency and thematic analysis enabled the subsequent examination.

Findings

A total of 94 sustainability indicators (44 environmental, 30 social and 20 economic) were identified in company reporting. The indicators correspond to the sustainability challenges identified in the literature. In addition to broad challenges, indicators are used to communicate specific issues. A significant number (47) of single-use indicators were identified, communicating less frequently reported challenges. Some companies account for sustainability from bean to cup, attributed to crucial differences in organisational characteristics (degree of vertical integration). Furthermore, the findings highlight the discretionary nature of sustainability reporting, finding considerable variance in indicators disclosed.

Research limitations/implications

As this paper relies on self-reported corporate disclosures, it critically examines the reporting practices of organisations, as opposed to verifying the activities associated with their claims. The authors minimised subjectivity by reducing the interpretation of what constituted “an indicator” using a clearly agreed definition and multiple rounds of coding.

Practical implications

This paper examines the reporting practices of organisations, providing a useful insight and a competitor benchmark. By comprehensively examining the sustainability challenges faced by the coffee industry, it offers “sustainability context” that can be used by organisations to improve their accounting and reporting practices.

Social implications

This paper acknowledges and addresses social initiatives that call for the systematic development of practical and appropriate sustainability indicators that can become embedded in policy and decision-making, affecting the measurement of progress and responses to important sustainability challenges.

Originality/value

This paper presents the first systematic review of sustainability indicator disclosure in an industry that faces significant sustainability challenges.
Críticas a la propuesta habermasiana de una racionalidad postsecular
Authors: Garzón Martínez Camilo Andrés , Hidalgo Nieto Catalina
Published: March 2018

El artículo se propone evaluar la propuesta normativa de Jürgen Habermas sobre lo que él ha denominado, de manera influyente, la sociedad postsecular. A través de una revisión del debate más general sobre cómo algunos autores ubican la religión en la esfera pública, el artículo propone, primero, una exposición sobre qué es a lo que nos referimos cuando hablamos de una sociedad postsecular. Segundo, profundiza en la propuesta normativa habermasiana para pasar a presentar algunas críticas que se le han hecho a su postura, añadiendo una crítica adicional que parte desde los aportes e intuiciones del diálogo intercultural. El artículo concluye reconociendo la importancia de una argumentación que no se resigne a la inconmensurabilidad o el conflicto entre los argumentos religiosos y seculares, pero recoge objeciones a la postura habermasiana tan-to de la cosecha de algunos de sus críticos como del diálogo intercultural, para señalar que esta, al exigir la traducción de los argumentos a un ámbito neutral del intercambio argumentativo, no responde satisfactoriamente a los escenarios y problemas inherentes al creciente pluralismo de las sociedades contemporáneas
El imaginario de la guerra a través del lenguaje de la televisión y las elecciones presidenciales de 2014 en Colombia
Authors: Guerrero Apráez Víctor , Amaya Rueda Santiago José
Published: March 2018

El artículo tiene como objetivo el análisis de las variables tipológicas contenidas en la serie televisiva Tres Caínes y examinar su estrategia representacional mediante una hermenéutica histórica y comparativa que permita dar cuenta de los diversos estereotipos icónico-dramáticos empleados y de una cierta visión del conflicto armado interno en Colombia, para correlacionarlo específicamente con la crucial coyuntura electoral del país en 2014, en cuya primera vuelta el presidente candidato fuera derrotado para sorpresa tanto de encuestadoras como de analistas, acotando su función legitimadora de las propuestas sostenidas por el uribismo y de apoyo mediático. Para este propósito, en primer lugar, se indaga sobre la funcionalidad del arte como herramienta política en los siglos XIX y XX, tomando como ejemplos la ópera nacionalista alemana e italiana y el cine de propaganda como herramienta de afectación colectivo-perceptiva en el contexto de la Segunda Guerra Mundial; en segundo lugar, se lleva a cabo un acercamiento teórico sobre las características de los géneros televisivos y los entrelazamientos entre realidad y ficción que configuran la serie Tres Caínes como un documento ficcional con pretensiones históricas. Finalmente, se encuentra una relación entre el nivel de exposición al serial (rating), mirado desde una perspectiva geográfica, y el mapa electoral de las elecciones presidenciales de 2014 en Colombia entre el candidato de la Unidad Nacional Juan Manuel Santos y el candidato opositor Óscar Iván Zuluaga.
Glosas sobre el riesgo asegurable en el contrato de seguro de vida
Authors: Díaz-Granados Prieto Juan José
Published: March 2018

Dado que el desarrollo doctrinario del contrato de seguro de vida ha sido escaso hasta el momento, este artículo intenta combatir este fenómeno otorgando herramientas conceptuales  sólidas a los operadores de seguros frente a un tema de vital importancia: el riesgo asegurable en el seguro de vida. Es por ello que por medio del presente escrito, el autor hace puntuales reflexiones frente a los temas más relevantes en materia del riesgo amparado por los negocios aseguraticios de este linaje, para de esta manera ofrecer conclusiones que, aparte de estar académicamente fundamentadas (siendo esto lo obvio), tiendan a ofrecer un elemento pragmático que tenga utilidad en el ejercicio profesional. De esta forma, además de los asuntos netamente jurídicos propios del fundamento de las conclusiones (como lo son las clases de riesgos asegurables en el seguro de vida, el alcance de sus conceptos y su naturaleza jurídica) el lector, a lo largo del texto, encontrará glosas relacionadas con hipótesis que no son comúnmente tratadas en el ámbito teórico, pero que a la hora de presentarse en el plano práctico, deben contar con suficientes elementos de juicio para ser resueltas, tal como ocurre con la cobertura de la muerte encefálica o cerebral, con los requisitos de la muerte presunta para ser un evento amparado, con la reaparición del asegurado tanto en seguros de muerte como de sobrevivencia, con el incumplimiento de la obligación de reembolso del beneficiario en caso de reaparición del otrora asegurado y con las consecuencias de la muerte presunta en el seguro de sobrevivencia, entre otros; todas estas situaciones que son analizadas en este texto. 
Evolution and the City
Authors: Bejan Adrian
Published: March 2018

This article analyzes the organization of a city in terms of how well it enables humans to move from any point to the whole area. In accordance with Constructal Law, the natural way to assemble and connect a road and street network is to ensure that travel time is reduced at every turn and with every change in the flow design. The article also highlights that predicting the future and constructing changes based on a proven scientific principle is much faster and more economical than trial and error. Due to the modern technology, urban design expands not only outward, into suburbs, and inward, toward dense city centers, but also vertically. Experts suggest that if we can anticipate the urban features that emerge naturally from the need for greater access, we can plan ahead and design with confidence the features that not only serve the population, but do so with staying power. A city is a live flow system with freely changing architecture, many small streets, few large streets, and beltways.
High-Tech Eyes
Authors: Kosowatz John
Published: March 2018

This article provides an overview of high-tech sensors, visual detection software, and mobile computing power applications, which are being developed to enable visually impaired people to navigate. By adapting technology developed for robots, automobiles, and other products, researchers and developers are creating wearable devices that can aid the visually impaired as they navigate through their daily routines—even identifying people and places. The Eyeronman system, developed by NYU’s Visuomotor Integration Laboratory and Tactile Navigation Tools, combines a sensor-laden outer garment or belt with a vest studded with vibrating actuators. The sensors detect objects in the immediate environment and relay their locations via buzzes on the wearer's torso. OrCam’s, a computer vision company in Jerusalem, team of programmers, computer engineers, and hardware designers have developed MyEye device, which attaches to the temple of a pair of eyeglasses. The device instructs the user on how to store items in memory, including things such as credit cards and faces of friends and family.
A Smooth Operator
Authors: Brown Alan S.
Published: March 2018

This article focuses on various features and advantages of the Smart Tissue Autonomous Robot (STAR), a robot being developed to perform tissue surgeries. Scientists believe that by embedding the knowledge of the best surgeons in digital systems, autonomous and semiautonomous robots could deliver universal access to the best surgical techniques. An autonomous robot must not only manipulate a needle and thread, but also follow—and react to—the shifting shapes that it creates in real time. STAR started its surgical career by working on rubbery pads with small protrusions. Surgeons use them to learn to stitch together wounds or tissues. The STAR research team plans to integrate additional sensors onto their robot to give surgeons better surgical information. Using a combination of force sensors and sophisticated multispectral cameras that see more than visible light, future robots might advise surgeons about tissue health, thickness, strength, and blood circulation. This would quantify knowledge that surgeons now learn only through experience.