bluuebunny/crossref_metadata_2025_split huggingface dataset:
Boosting heterologous protein production yield by adjusting global nitrogen and carbon metabolic regulatory networks inBacillus subtilis
Authors: Cao Haojie , Villatoro-Hernandez Julio , Weme Ruud Detert Oude , Frenzel Elrike , Kuipers Oscar P. 
Published: May 2018

AbstractBacillus subtilisis extensively applied as a microorganism for the high-level production of heterologous proteins. Traditional strategies for increasing the productivity of this microbial cell factory generally focused on the targeted modification of rate-limiting components or steps. However, the longstanding problems of limited productivity of the expression host, metabolic burden and non-optimal nutrient intake, have not yet been solved to achieve production strain improvements. To tackle this problem, we systematically rewired the regulatory networks of the global nitrogen and carbon metabolism by random mutagenesis of the pleiotropic transcriptional regulators CodY and CcpA, to allow for optimal nutrient intake, translating into significantly higher heterologous protein production yields. Using a β-galactosidase expression and screening system and consecutive rounds of mutagenesis, we identified mutant variants of both CcpA and CodY that in conjunction increased production levels up to 290%. RNA-Seq and electrophoretic gel mobility shift analyses showed that amino acid substitutions within the DNA-binding domains altered the overall binding specificity and regulatory activity of the two transcription factors. Consequently, fine-tuning of the central metabolic pathways allowed for enhanced protein production levels. The improved cell factory capacity was further demonstrated by the successfully increased overexpression of GFP, xylanase and a peptidase in the double mutant strain.HighlightsThe global transcription machinery engineering (gTME) technique was applied to build mutational libraries of the pleiotropic regulators CodY and CcpA inBacillus subtilisSpecific point mutations within the DNA-binding domains of CodY and CcpA elicited alterations of the binding specificity and regulatory activityChanges in the transcriptome evoked the reprogramming of networks that gear the carbon and nitrogen metabolismThe rewired metabolic networks provided a higher building block capacity for heterologous protein production by adjusting the nutrient uptake and channeling its utilization for protein overexpression
Single-cell transcriptome profiling of theCionalarval brain
Authors: Sharma Sarthak , Wang Wei , Stolfi Alberto 
Published: May 2018

AbstractThe tadpole-type larva ofCionahas emerged as an intriguing model system for the study of neurodevelopment. TheCiona intestinalisconnectome has been recently mapped, revealing the smallest central nervous system (CNS) known in any chordate, with only 177 neurons. This minimal CNS is highly reminiscent of larger CNS of vertebrates, sharing many conserved developmental processes, anatomical compartments, neuron subtypes, and even specific neural circuits. Thus, theCionatadpole offers a unique opportunity to understand the development and wiring of a chordate CNS at single-cell resolution. Here we report the use of single-cell RNAseq to profile the transcriptomes of single cells isolated by fluorescence-activated cell sorting (FACS) from the whole brain ofCiona robusta(formerlyintestinalis Type A)larvae. We have also compared these profiles to bulk RNAseq data from specific subsets of brain cells isolated by FACS using cell type-specific reporter plasmid expression. Taken together, these datasets have begun to reveal the compartment- and cell-specific gene expression patterns that define the organization of theCionalarval brain.
Simulating Contact Using the Elastic Foundation Algorithm in OpenSim
Authors: Hast Michael W. , Hanson Brett G. , Baxter Josh R. 
Published: May 2018

AbstractModeling joint contact is necessary to test many questions using simulation paradigms, but this portion of OpenSim is not well understood. The purpose of this study was to provide a guide for implementing a validated elastic foundation contact model in OpenSim. First, the load-displacement properties of a stainless steel ball bearing and ultra high molecular weight polyethylene (UHMWPE) slab were recorded during a controlled physical experiment. These geometries were imported and into OpenSim and contact mechanics were modeled with the on-board elastic foundation algorithm. Particle swarm optimization was performed to determine the elastic foundation model stiffness (2.14×1011 ± 6.81×109 N/m) and dissipation constants (0.999 ± 0.003). Estimations of contact forces compared favorably with blinded experimental data (root mean square error: 87.58 ± 1.57 N). Last, total knee replacement geometry was used to perform a sensitivity analysis of material stiffness and mesh density with regard to penetration depth and computational time. These simulations demonstrated that material stiffnesses between 1011 and 1012 N/m resulted in realistic penetrations (< 0.15mm) when subjected to 981N loads. Material stiffnesses between 1013 and 1015 N/m increased computation time by factors of 12–23. This study shows the utility of performing a simple physical experiment to tune model parameters when physical components of orthopaedic implants are not available to the researcher. It also demonstrates the efficacy of employing the on-board elastic foundation algorithm to create realistic simulations of contact between orthopaedic implants.
Extensile motor activity drives coherent motions in a model of interphase chromatin
Authors: Saintillan David , Shelley Michael J. , Zidovska Alexandra 
Published: May 2018

AbstractThe 3D spatiotemporal organization of the human genome inside the cell nucleus remains a major open question in cellular biology. In the time between two cell divisions, chromatin – the functional form of DNA in cells – fills the nucleus in its uncondensed polymeric form. Recent in-vivo imaging experiments reveal that the chromatin moves coherently, having displacements with long-ranged correlations on the scale of microns and lasting for seconds. To elucidate the mechanism(s) behind these motions, we develop a novel coarse-grained active-polymer model where chromatin is represented as a confined flexible chain acted upon by molecular motors, which perform work by exerting dipolar forces on the system. Numerical simulations of this model account for steric and hydrodynamic interactions as well as internal chain mechanics. These demonstrate that coherent motions emerge in systems involving extensile dipoles and are accompanied by large-scale chain reconfigurations and nematic ordering. Comparisons with experiments show good qualitative agreement and support the hypothesis that self-organizing long-ranged hydrodynamic couplings between chromatin-associated active motor proteins are responsible for the observed coherent dynamics.
Robot learning human stiffness regulation for hybrid manufacture
Authors: Zeng Chao , Yang Chenguang , Chen Zhaopeng , Dai Shi-Lu 
Published: May 2018

Purpose
Teaching by demonstration (TbD) is a promising way for robot learning skills in human and robot collaborative hybrid manufacturing lines. Traditionally, TbD systems have only concentrated on how to enable robots to learn movement skills from humans. This paper aims to develop an extended TbD system which can also enable learning stiffness regulation strategies from humans.

Design/methodology/approach
Here, the authors propose an extended dynamical motor primitives (DMP) framework to achieve this goal. In addition to the advantages of the traditional ones, the authors’ framework can enable robots to simultaneously learn stiffness and the movement from human demonstrations. Additionally, Gaussian mixture model (GMM) is used to capture the features of movement and of stiffness from multiple demonstrations of the same skill. Human limb surface electromyography (sEMG) signals are estimated to obtain the reference stiffness profiles.

Findings
The authors have experimentally demonstrated the effectiveness of the proposed framework. It shows that the authors approach could allow the robot to execute tasks in a variable impedance control mode with the learned movement trajectories and stiffness profiles.

Originality/value
In robot skill acquisition, DMP is widely used to encode robotic behaviors. So far, however, these DMP modes do not provide the ability to properly represent and generalize stiffness profiles. The authors argue that both movement trajectories and stiffness profiles should be considered equally in robot skill learning. The authors’ approach has great potential of applications in the future hybrid manufacturing lines.
Talent turnover and retention research
Authors: Alferaih Adel , Sarwar Shagufta , Eid Ayman 
Published: May 2018

PurposeThe purpose of this paper is to understand the direct impact of some of the salient factors from the talent management (TM) literature (role conflict, extrinsic rewards, and job satisfaction) and the indirect impact of other factors (organisational commitment, talent retention, and talent engagement) on talent turnover intention.Design/methodology/approachA survey questionnaire collected 521 valid responses from employees holding managerial and non-managerial positions at various levels in 54 five-star hotels in 6 cities in Saudi Arabia.FindingsSignificant support was found for all nine hypotheses formulated to test the relationships among the seven constructs above. The model was found to explain 68 per cent of variance in talent turnover intention.Research limitations/implicationsThe study contributes to human resource management literature in general and TM in particular by examining the different constructs used in the TM models and by conceptualising a research model, which was empirically validated within the service sector in the context of Saudi Arabia.Practical implicationsThe research has several implications for practitioners in the tourism/service sector in the Middle East, pertaining to the management of talented employees. Specifically, it recommends that managers should promote training and development scenarios and provide a better work environment to strengthen individuals’ commitment to their jobs.Originality/valueThis is one of the first studies to examine a comprehensive model of TM in the Arab world in general and in Saudi Arabia in particular, using data gathered from employees in the tourism sector.
Incentive pay configurations: the influence of national culture
Authors: Prince Nicholas R. , Prince J. Bruce , Kabst Rüediger 
Published: May 2018

PurposeThe purpose of this paper is to investigate the influence of national culture on the adoption of four different incentive pay bundles (incentive maximizer, contingent rewarder, profit rewarder, and incentive minimizer) using GLOBE national culture dimensions in 14 countries. It uses incentive pay bundles derived by Princeet al.(2016).Design/methodology/approachThe study adopted multilevel random-intercept logistic modeling using firm incentive practice usage from the CRANET database and country culture scores from the GLOBE study.FindingsEvidence suggests that in-group collectivism is associated with increased use of the incentive maximizer approach, in which firms use a combination of high levels of individual, team, and profit sharing incentives, and decreased use of the incentive minimizer approach (where firms minimally employ incentives) and the individual and team bonus focused contingent rewarder configuration. Higher uncertainty avoidance is linked to increased use of the profit rewarder approach (where only profit sharing is emphasized) and decreased use of the contingent rewarder approach. Performance-orientation cultures appear to support using the incentive maximizer and avoiding the incentive minimizer bundles.Originality/valueThis study investigates incentive practice bundles that firms use verses separate analysis of practices and use the GLOBE culture metrics. It utilizes multilevel modeling, which has been lacking in past studies of culture and incentives.
The role of family in the township informal economy of food and drink in KwaMashu, South Africa
Authors: Petersen Leif , Charman Andrew 
Published: May 2018

Purpose
The purpose of this paper is to provide a qualitative investigation of family employment dynamics in the KwaMashu township economy.

Design/methodology/approach
Using a small area census research method, the researchers identified 1,556 businesses located in a settlement of 2 km2. Of these enterprises, 694 (45 percent) traded in fast moving consumer goods, notably food and/or drink. The main retailers were small shops (spaza shops) and liquor outlets (bars or shebeens), greengrocers, sellers of meat and poultry products, house shops, restaurants, takeaways and tuckshops. Firm surveys were conducted with 270 businesses in four predominant sectors: liquor retail, grocery retail, early childhood educators and hair care businesses.

Findings
The research found that 40 percent of the surveyed firms in these sectors employ family members on a full-time basis, whereas merely 26 percent of firms employ family members on a part-time basis. In the grocery retail sector, about half of family employees are remunerated on a wage basis, the other half are paid in-kind (40 paper of the total) or on a profit share arrangement. In liquor retail and educare sectors, the majority of family members are paid wages. Female-run enterprises employ less family members on a full-time basis (except in the grocery sector), yet employ more family members on a part-time basis with a higher portion of wages paid in-kind.

Research limitations/implications
Family plays an important role in township enterprises. Beyond direct employment, township enterprises fulfill an important social protection and neighborhood relationship function for business operators and their families. The familial relationship to micro-enterprises should be seen through the lens of bricolage (Gras and Nason, 2015).

Originality/value
In this respect, the authors confirm three benefits of family firms: the creation of social protection though family beneficiation, the provision of employment and work experience and the strategic use of family resources.
Effects of gender quotas in Italy: a first impact assessment in the Italian banking sector
Authors: De Vita Luisa , Magliocco Antonella 
Published: May 2018

Purpose
The purpose of this paper is to provide a first impact assessment of the Italian quota law in order to explore whether “gender equality by law” contributes to redefining, albeit in part, consolidating and establishing positions of power and decision making. The paper analyses these dynamics by focusing on a specific economic sector, the banking sector. The analysis strives to determine: whether binding quotas are giving rise to an apparent enforcement by building up new distortionary equilibria (such as new forms of horizontal segregation); what extent the financial crisis has impacted on the rhetoric of female representation, and whether it has pushed towards a “regenerative” organizational change aimed at achieving a more inclusive and egalitarian image.

Design/methodology/approach
The paper is organized as follows. Section 2 reviews the theoretical and empirical debate on gender diversity and quota impact. Section 3 reports macro and micro data on the italian system; Section 4 describes the Italian banking system and gives a first impact assessment on Italian banks of the mandatory gender quotas in Italy (the so-called “Golfo-Mosca law,” named after MPs who proposed the law); some qualitative considerations are carried out on the reactions of Italian banks to the financial crisis in terms of “bridge policies” aimed at corresponding to a higher demand of customer satisfaction and fairness. Section 5 concludes and summarizes the finding of the study.

Findings
The Italian banking system is not so dramatically ranked among the EU countries as in the recent past. The gender rebalance in management bodies could be considered rather satisfying. If we compare ten-year-old findings, the number of women on board of directors has tripled. But data clearly show a dichotomy due to significant differences between listed and non-listed banks. In non-listed banks, women are still relegated to an under-represented position, reaching only 13 percent on boards of directors (as against 33 percent in listed banks). The data confirm the results found in non-financial sector that women are significantly better represented on audit boards. In accordance with all previous studies, no relevant changes can be noticed on key-decision roles: no CEOs or Directors general are women in listed banks, and women are always more represented in non-executive functions.

Originality/value
The paper analyses the law experience in Italy as a significant case study by proving that rules such as temporary binding gender quotas (introduced by law in 2011) can be useful, but not always enough to remove blocking or distortive factors in organizational ladders.
Whose home is it anyway? Performing multiple selves while doing organizational ethnography
Authors: Cnossen Boukje 
Published: May 2018

Purpose
The purpose of this paper is to nuance the idea of natural access proposed by Mats Alvesson in his description of at-home ethnography, and to offer a performative view of Alvesson’s suggestion that, in at-home ethnography, the ethnographer must work with “the processual nature of the researcher’s self.”

Design/methodology/approach
The author offers a reflection on the several years of ethnographic research the author conducted, of which some parts were done in a living community of which the author was part. Being literally at home, as well as being very familiar in the other research settings the author describes, allows for a critical reflection on what “at-homeness” means.

Findings
Using Butler’s notion of performativity, the author argues that “the processual nature of the researcher’s self” Alvesson speaks of, can best be understood as multiple selves, of which some emerge during the research process. The author furthermore problematizes Alvesson’s use of the term “natural access,” by arguing that this kind of access is neither easy, nor devoid of power relations.

Originality/value
This paper uses an experience of conducting research in the home, as well as an experience conducting research in a setting where the researcher arguably blent in well, to question what the “at-home” in at-home ethnography means, and how the researcher can deal with it.
Assessing the effects of multichannel service provider corporate reputation on customer new product adoption and RFM value
Authors: Walsh Gianfranco , Schaarschmidt Mario , Ivens Stefan 
Published: May 2018

Purpose
Service providers leverage their corporate reputation management efforts to increase revenues by shaping customer attitudes and behaviours, yet the effects on customer innovation adoption and customer value remain unclear. In an extended conceptualisation of customer-based corporate reputation (CBR), the purpose of this paper is to propose that customer perceived risk, perceived value, and service separation are contingencies of the relationship between CBR and two key customer outcomes: customer new product adoption proneness (CPA) and recency-frequency-monetary (RFM) value.

Design/methodology/approach
Using a predictive survey approach, 1,001 service customers assess the online or offline operations of six multichannel retailers. The hypothesised model is tested using structural equation modelling and multigroup analysis.

Findings
The analysis reveals significant linkages of CBR with perceived risk and perceived value, as well as between perceived risk and perceived value and from perceived value to CPA and RFM value. These linkages vary in strength across unseparated (offline) and separated (online) services.

Research limitations/implications
This study uses cross-sectional data to contribute to literature that relates CBR to relevant customer outcomes by considering CPA and RFM value and investigating contingent factors. It provides conceptual and empirical evidence that price appropriateness represents a new CBR dimension.

Practical implications
The results reveal that CBR reduces customers’ perceived risk and positively affects their perceived value, which drives CPA and RFM value. Multichannel retailers can create rewarding customer relationships by building and nurturing good reputations.

Originality/value
This study is the first to link CBR with customer product adoption proneness and value, two important customer measures. It proposes and tests an extended conceptualisation of CBR.
Determinants of cluster leadership and identification on cluster innovation model
Authors: Chen Chun-Liang , Lin Yao-Chin , Chen Wei-Hung , Heng Xin-Si 
Published: May 2018

Purpose
The purpose of this paper is to prove the importance of both cluster leadership and identification on cluster innovation.

Design/methodology/approach
The case studies presented in this study involve a cluster by micro-enterprises in Yilan, Taiwan. Data collected during interviews, observations and secondary data provide understanding and practices for the impact of cluster identification on cluster innovation.

Findings
This study proved: first, the importance of cluster identification on innovation by representing the need of consensus and collaboration of the members in conducting innovation actions; and second, the cluster identification is influenced by the cluster leadership by showing high satisfaction of the leader, close interaction between the members and high identification with the cluster.

Research limitations/implications
This study predicts the ongoing cluster innovation activities will be achieved due to the transformational leadership and high cluster identification.

Originality/value
This study enriches the factors of cluster innovation accomplishment and proposes the important of cluster identification, which has not been discussed much in the past.
Foreign firms’ strategic positioning and performance in a host market
Authors: Xie Henry Yu , Xie Qian (Jane) , Zhao Hongxin 
Published: May 2018

PurposeStrategic positioning of foreign firms in a host market is vital for their success. By integrating the resource partitioning theory and the resource-based view, this study aims to investigate foreign firms’ strategic positioning (i.e. their choice of generalist or specialist positioning strategy) and its performance implications in the US market.Design/methodology/approachThe final sample includes 212 foreign companies from 28 countries operating in the US market. Multiple data sources were used to collect data of these foreign companies’ subsidiaries in the USA This study used logistic regression to test its major hypotheses.FindingsThe results of this study suggest that a generalist positioning strategy is positively related to performance in a host market. It is also found that market concentration and local market knowledge moderate this strategic positioning – performance relationship.Research limitations/implicationsFor a foreign firm that enters a host market, market concentration (an industry-level factor) in the host market and the firm’s local market knowledge (a firm-specific factor) play prominent roles in the strategic positioning – performance relationship.Originality/valueThis study offers a novel perspective of international business strategy by applying the lens of resource partitioning theory to study the relationships between multinational enterprises’ strategic positioning and performance. This study contributes to the strategy literature in that it examines the performance implications of firms’ strategic positioning (i.e. generalist or specialist positioning).