bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low dimensional morphospace of topological motifs in human fMRI brain networks
Authors: Morgan Sarah E. , Achard Sophie , Termenon Maite , Vértes Petra E. , Bullmore Edward T. 
Published: June 2017

AbstractWe present a low-dimensional morphospace of fMRI brain networks, where axes are defined in a data-driven manner based on the network motifs. The morphospace allows us to identify the key variations in healthy fMRI networks in terms of their underlying motifs and we observe that two principal components (PCs) can account for 97% of the motif variability. The first PC corresponds to the small-world axis and correlates strongly with the networks’ global efficiency. There is also some evidence that PC1 correlates with the average length of the 5% of longest edges in the network. Hence this axis represents the trade-off between the cost of long distance edges and their topological benefits. The second PC correlates with the networks’ assortativity. Finally, we show that the economical clustering generative model proposed by Vértes et al. can approximately reproduce the motif PC space of the real fMRI brain networks, in contrast to other generative models. Overall, the motif morphospace provides a powerful way to visualise the relationships between network properties and to study the driving forces behind the topology of fMRI brain networks.
LPP3 mediates self-generation of chemotactic LPA gradients by melanoma cells
Authors: Susanto Olivia , Koh Yvette W.H. , Morrice Nick , Tumanov Sergey , Thomason Peter A. , Nielson Matthew , Tweedy Luke , Muinonen-Martin Andrew J. , Kamphorst Jurre J. , Mackay Gillian M. , Insall Robert H. 
Published: June 2017

AbstractMelanoma cells steer out of tumours using self-generated lysophosphatidic acid (LPA) gradients. The cells break down LPA, which is present at high levels around the tumours, creating a dynamic gradient that is low in the tumour and high outside. They then also migrate up this gradient, creating a complex and evolving outward chemotactic stimulus. Here we introduce a new assay for self-generated chemotaxis, and show that raising LPA levels causes a delay in migration rather than loss of chemotactic efficiency. Knockdown of the lipid phosphatase LPP3 - but not its homologues LPP1 or LPP2 - diminishes the cell’s ability to break down LPA. This is specific for chemotactically active LPAs, such as the 18:1 and 20:4 species. Inhibition of autotaxin-mediated LPA production does not diminish outward chemotaxis, but loss of LPP3-mediated LPA breakdown blocks it. Similarly, in both 2D and 3D invasion assays, knockdown of LPP3 diminishes melanoma cells’ ability to invade. Our results demonstrate that LPP3 is the key enzyme in melanoma cells’ breakdown of LPA, and confirm the importance of attractant breakdown in LPAmediated cell steering.
Lack of dynamic balance between vesicle transport and microtubule growth in neurite outgrowth enables formation of dystrophic bulbs
Authors: Yadaw Arjun Singh , Siddiq Mustafa M. , Rabinovich Vera , Tolentino Rosa , Iyengar Ravi , Hansen Jens 
Published: June 2017

AbstractWhole cell responses involve multiple subcellular processes (SCPs). To understand how balance between SCPs controls the dynamics of whole cell responses we studied neurite outgrowth in rat primary cortical neurons in culture. We used a combination of dynamical models and experiments to understand the conditions that permitted growth at a specified velocity and when aberrant growth could lead to the formation of dystrophic bulbs. We hypothesized that dystrophic bulb formation is due to quantitative imbalances between SCPs. Simulations predict redundancies between lower level sibling SCPs within each type of high level SCP. In contrast, higher level SCPs, such as vesicle transport and exocytosis or microtubule growth characteristic of each type need to be strictly coordinated with each other and imbalances result in stalling of neurite outgrowth. From these simulations, we predicted the effect of changing the activities of SCPs involved in vesicle exocytosis or microtubule growth could lead to formation of dystrophic bulbs. siRNA ablation experiments verified these predictions. We conclude that whole cell dynamics requires balance between the higher-level SCPs involved and imbalances can terminate whole cell responses such as neurite outgrowth.
Alpha EEG power reflects the suppression of Pavlovian bias during social reinforcement learning
Authors: Thompson James C , Westwater Margaret L 
Published: June 2017

Socially appropriate behavior involves learning actions that are valued by others and those that have a social cost. Facial expressions are one way that others can signal the social value of our actions. The rewarding or aversive properties of signals such as smiles or frowns also evoke automatic approach or avoidance behaviors in receivers, and a Pavlovian system learns cues that predict rewarding or aversive outcomes. In this study, we examined the computational and neural mechanisms underlying interactions between Pavlovian and Instrumental systems during social reinforcement learning. We found that Pavlovian biases to approach cues predicting social reward and avoid cues predicting social punishment interfered with Instrumental learning from social feedback. While the computations underlying Pavlovian and Instrumental interactions remained the same as when learning from monetary feedback, Pavlovian biases from social outcomes to approach or withdraw were not significantly correlated with biases from money. Trial-by-trial measures of alpha (8-14Hz) EEG power was associated with suppression of Pavlovian bias to social outcomes, while suppression of bias from money was associated with theta (4-7Hz) EEG power. Our findings demonstrate how emotional reactions to feedback from others are balanced with the instrumental value of that feedback to guide social behavior.Significance statementA smile from another can be a signal to continue what we are doing, while an angry scowl is a sure sign to stop. Feedback from others such as this plays an important role in shapeing social behavior. The rewarding nature of a smile (or the aversive nature of a scowl) can also lead to automatic tendencies to approach (or avoid), and we can learn situations that predict positive or negative social outcomes. In this study, we examined the brain mechanisms that come into play when the instrumental demands of a situation are in conflict with our automatic biases to approach or withdraw, such as when we have to approach someone who is scowling at us or withdraw from someone who is smiling.
Analysis of RAS as a tumor suppressor
Authors: Kenney Chelsey , Stites Edward C. 
Published: June 2017

ABSTRACTThe RAS GTPases are among the best-understood oncogenes that promote human cancer. Many have argued that non-mutated, wild-type, RAS also functions as a tumor suppressor. The arguments for RAS tumor suppressor activity often involve data that are claimed to be inconsistent with known principles of RAS biology. RAS tumor suppressor activity is invoked to explain these observations. Here, we consider an alternative hypothesis: these data are actually consistent with RAS biology. We investigate by using our previously developed mathematical model of RAS regulation. We find that three of five arguments for RAS having tumor suppressor activity are based upon data that the model demonstrates are actually consistent with known RAS biology. We also find that the other two types of data interpreted to indicate a tumor suppressor effect can be explained by our model with the additional assumption that RAS protein expression does not vary proportionally with gene dosage. Measurements of RAS protein expression as a function of gene dosage could help resolve whether or not RAS has tumor suppressor activity. Overall, we conclude that the evidence for RAS having tumor suppressor activity is much less strong that it has appeared.
A computational panel of pathological RAS mutants with implications for personalized medicine and genetic medicine
Authors: Kenney Chelsey , Stites Edward C. 
Published: June 2017

ABSTRACTThe RAS proteins (KRAS, NRAS, and HRAS) play important roles in multiple diseases. This includes many types of cancer and the developmental syndromes collectively referred to as the RASopathies. There are many different RAS mutants that are found to drive these diseases. Mutant-to-mutant differences pose a challenge for personalized medicine. To investigate this problem, we extend our previously developed model of oncogenic RAS mutants to a total of 16 oncogenic mutants. We also extend our model to RASopathy associated mutants using data for 14 such RAS mutants. The model finds that the known biochemical defects of these mutants are typically sufficient to explain their elevated levels of RAS signaling. In general, our analysis finds that the oncogenic mutants are stronger than the RASopathy mutants. However, the model suggests that RAS signal intensities are spanned by the pathological variants; there does not appear to be a perfect separation between cancer promoting and developmental syndrome promoting mutants. Analysis of the panel also finds that the relative strengths of pathological RAS mutants is not absolute, but rather can vary depending on context. We discuss implications of this finding for personalized cancer medicine and for medical genetics. As genomics permeates clinical medicine, computational models that can resolve mutant specific differences, like the one presented here, may be useful for augmenting clinical thinking with their ability to logically translate biochemical knowledge into system level outputs of perceived clinical relevance.
Global Efficiency of Retinal Networks shows Robustness and Degenerate States
Authors: Signorelli Camilo Miguel 
Published: June 2017

AbstractThis exploratory project report provides a study of the retina in response to spontaneous and evoked pattern of flashes for different time cycles. These patterns induce changes at individual neural level and network level, while global efficiency, a topological network measure, presents robustness and degenerate states across time. This report also discusses some alternatives to explain changes observed and how it could be related to oscillatory plasticity mechanism.
The dynamics between entrepreneurial orientation, transformational leadership, and intrapreneurial intention in Iranian R&D sector
Authors: Razavi Seyed Hadi , Ab Aziz Kamarulzaman 
Published: June 2017

PurposeThe purpose of this paper is to examine the relationship between entrepreneurial orientation (EO) and intrapreneurial intentions among knowledge workers in the Iranian R&D sector using transformational leadership (TL) as a moderator and to also investigate the extent of the knowledge workers’ intrapreneurial intentions.Design/methodology/approachThe research was tested as a cross-sectional survey of knowledge workers involved in the R&D centers in Iran under the Society of the Centers for Research. The sampling method in this study was based on simple random sampling. Finally, 380 valid questionnaires were collected from 48 R&D centers of different industries.FindingsThe findings of this study reveal that except for the “need for achievement (NFA),” other variables such as “innovativeness,” “proactiveness,” “risk taking,” and “networking” had a significant and positive relationship toward “intrapreneurial intention.” Moreover, it was found that “TL” had a moderating role in the relations between innovativeness, proactiveness, and risk taking with intrapreneurial intention; however, TL did not have a moderating role in the relations between NFA and networking with intrapreneurial intention.Research limitations/implicationsReliance on cross-sectional questionnaires instead of an experimental design imposes caution about the relationships between the predictors and intrapreneurial intention.Originality/valueThis paper is one of the few studies on the EO at the individual level with new dimensions on the intrapreneurial intention, which examined moderating role of TL at this relationship, which took place in Iranian R&D sector.
E-portfolios and personal development: a higher educational perspective
Authors: McKenna Gary , Baxter Gavin , Hainey Thomas 
Published: June 2017

PurposeThe purpose of this paper is to investigate the attitudes of staff and students towards adopting the use of e-portfolios for the purposes of supporting the concept of personal development planning (PDP). The study compares and contrasts the views and opinions of staff and students at one UK Higher Education Institution (HEI) about whether e-portfolios can support PDP.Design/methodology/approachAdopting a case study approach, this study presents empirical data gathered from two surveys involving 460 students and 182 lecturers from one UK HEI, collected from four different campuses across the West of Scotland.FindingsThe results of the surveys showed that the framework the authors used in the research to collect information about students and staffs attitudes was effective and that further research is merited for a more extensive investigation into PDP e-portfolio usage within HEI.Research limitations/implicationsThe research was conducted at only one UK HEI so at this stage of the research, it is difficult to assess how generalisable the findings are.Practical implicationsThis study provides useful empirical evidence to educators who may be considering employing e-portfolios within an educational context. For example, the views of students and staff identified in this paper can aid towards informing educators about some of the issues that might impact on using e-portfolios for supporting PDP in higher education.Originality/valueTo the best of the authors’ knowledge, this is the first work that presents survey data on both students’ and lecturers’ attitudes towards e-portfolio use to support and facilitate PDP.
Emotional reframing as a mediator of the relationships between transformational school leadership and teachers’ motivation and commitment
Authors: Berkovich Izhak , Eyal Ori 
Published: June 2017

PurposeEmpirical evidence links transformational school leadership to teachers’ autonomous motivation and affective organizational commitment. Little empirical research, however, has focused on the emotional mechanisms behind these relations. Following the argument in the literature that transformational leadership can transform followers’ emotions, the purpose of this paper is to examine whether teacher’s experience of emotional reframing by principal mediates the relationships between transformational school leadership and these work-related outcomes (i.e. teachers’ motivation and commitment).Design/methodology/approachQuestionnaires were used to collect information from 639 primary school teachers nested in 69 randomly sampled schools. The data were analyzed using multilevel path analysis software.FindingsThe results indicated that the effect of transformational school leadership behaviors on teachers’ autonomous motivation was fully mediated by emotional reframing, and that the effect of transformational school leadership on affective organizational commitment was partially mediated by it. The authors further found an indirect relationship of transformational school leadership with affective organizational commitment through emotional reframing and autonomous motivation.Originality/valueThe present study makes a unique contribution to the literature by confirming that teachers’ sense of emotional reframing is a key affective mechanism by which school leaders influence teachers’ motivation and commitment.
Financial performance and operating strategies of Malaysian property development companies during the global financial crisis
Authors: Chan Toong Khuan , Abdul-Aziz Abdul-Rashid 
Published: June 2017

Purpose
The purpose of this paper is to characterise the financial performance and to identify the operating strategies of property development companies in Malaysia during the 2008 global financial crisis (GFC).

Design/methodology/approach
The research approach includes a comprehensive analysis of the financial statements and annual reports of 35 property development companies listed on the Kuala Lumpur stock exchange. The financial statements were analysed to evaluate the financial performance of these companies and to assess the severity of the impact of the GFC on revenues and profits. The operating strategies were determined from a content analysis of the statement to shareholders.

Findings
An aggregated analysis of the financial performance indicates a 23 per cent decline in net profit in 2008. Classifying these companies into two separate sets of distressed and non-distressed companies showed that poor financial performance and a high debt-to-equity ratio pre-GFC led to continuing poor performance during the GFC period and beyond. Survival strategies adopted by distressed companies include the disposal of assets to improve cash flow, refinancing loans, delaying the launch of new projects and reducing their workforce. Non-distressed companies adopted growth strategies such as purchasing land for development, focusing their offerings towards high-end products, vertically integrating and diversification.

Practical implications
The increased understanding of the financial performance and operational strategies will allow managers of property development companies to improve financial management and adopt appropriate strategies in response to the impact of future financial distress.

Originality/value
The study presented in this paper is the first to analyse the financial performance of Malaysian public-listed property development companies during the period of the 2008 GFC and to link their financial performance to operational strategies.
Simulation of charring depth of timber structures when exposed to non-standard fire curves
Authors: Mindeguia Jean-Christophe , Cueff Guillaume , Dréan Virginie , Auguin Gildas 
Published: June 2017

Purpose
The fire resistance of wooden structures is commonly based on the calculation or measurement of the char layer. Designers usually estimate the char layer at the surface of a structural element by using analytical models. Some of these charring models can be found in regulations, as Eurocode 5. These analytical models, quite simple to use, are only reliable for the standard fire curve. In that case, the design of the structure is qualified as “prescriptive-based design” and can lead to oversizing the structure. Optimization of a structure can be achieved by using a “Performance-based design”, where realistic fire scenarios are taken into account by means of more or less complex models [parametric fires, two-zones models, computational fluid dynamics (CFD)]. For these so-called “natural fires”, no model for charring is available. The purpose of this paper is to present a novel methodology for applying a performance-based design to a simple timber structure.

Design/methodology/approach
This paper presents the development of a numerical model aiming to simulate the thermal transfer and charring in wood, under any type of thermal exposure, including non-standard fire curves. After presenting the physical background, the model is calibrated and compared to existing experimental studies on wood samples exposed to different fire curves. The model is then used as a tool for assessing the fire resistance of a common wooden structure exposed to standard and non-standard fire curves.

Findings
The results show that the fire resistance is obviously dependent on the choice of the thermal exposure. The reliability of the model is also discussed and the importance of taking into account particular reactions in wood during heating is underlined.

Originality/value
One aim of this paper is to show the opportunity to apply a performance-based approach when designing a wooden structure. It shows that more knowledge of the material behaviour under non-standard fires is still needed, especially during the decay phase.
Advanced analyses of the membrane action of composite slabs under natural fire scenarios
Authors: Lelli Lorenzo , Loutan Jonas 
Published: June 2017

PurposeThis paper aims to detail the advanced natural fire simulations that were carried out for the composite steel-reinforced concrete structure of the JTI Building in Geneva, Switzerland. The results of these analyses led to a significant reduction of in the fireproofing of the steel floor framing.Design/methodology/approachSeveral scenarios were studied considering different thermal behaviours of the peripheral cladding. Despite the small thickness of the resisting slabs, the analyses performed with SAFIR software showed that the typical wide storey bay (12 × 15.86 m) can resist to the design’s fire temperatures without the protection of the main and secondary beams while the spandrels remain protected. For study completeness, the composite frame-membrane model was also simulated with Hasemi-localized fire routines on SAFIR.FindingsThe analyses have showed that the membrane behaviour of composite slabs under fire allows a significant reduction of the fire protection, even in case of small thickness of the concrete topping. The increase of the reinforcement ratio to sustain the membrane forces is widely compensated by the savings related to the fireproofing of the steel framing.Practical/implicationsA natural fire approach is particularly advisable in case of fully glazed buildings. In fact when the façade collapses, the entry of a large cold air quantity limits the increase of the gas temperature inside the compartment.Originality/valueThe analyses were carried out with recent SAFIR routines for localized fires (Hasemi fire model) and represent one of the first applications in practice. The issue of the rebar orientation in mesh is raised out. The latest SAFIR release allows the definition of a global orientation of the rebars and amends the issue.
Political Representation on the New Auckland Council – Has Amalgamation Led to Greater Diversity?
Authors: Webster Karen Lesley , Fa'apoi Emiliana 
Published: June 2017

AbstractThis paper explores the diversity of local government electoral candidates and elected members, in Auckland – one of the world's most diverse cities (Chen 2015: 56) – following the 2010 amalgamation. It responds to questions raised over the democratic gaps created by enlarged wards, a lack of diverse representation, and higher elected member ratios. The research asks the question – who stood and who was elected in the election following the Auckland 2010 reforms, and how does this compare with the city's diverse population. Pitkin's (1967) concept of descriptive representation provides the foundation for a comparison of the gender, age, and ethnicity of local population, local government candidates, and elected members, to ascertain descriptive representation. The human rights framework provides a theoretical foundation to examine the diversity of representation. Preliminary findings support the view that under the shared governance model, electoral candidates are becoming more ethnically and gender diverse at the local level; while at the regional level, the dominance of the archetypal councillor as European, middle‐aged and male, prevails.