Engagement of Information Systems Professionals in Open Source Software Development

Open source (OS) development of software is becoming increasingly desirable for individuals and organizations alike. Organizations that heavily resisted this new way of developing software are now actively participating in this process. Participation of information systems (IS) professionals in the open source environment has been a focal point in this stream of research in information systems. The dissertation goes beyond participation and examines engagement of IS professionals in the open source environment. The concept of engagement facilitates a more comprehensive understanding of the relationship between a person and a his or her work. The three essays in the dissertation examine three aspects of IS professional’s engagement in the open source domain: job engagement, platform engagement, and continued participation. The first essay, using the job characteristics model as a theoretical framework, explores the role of job characteristics in driving job engagement and job satisfaction in open source projects. The second essay examines factors that can influence IS professionals continued contribution to future activities of an open source development platform. Using the social exchange theory, the second essay examines how perceived justice of rewards in OS projects can impact IS professionals’ platform engagement and intention to participate in future platform activities. The third essay explores the role of external feedbacks in open source projects. Using the signaling theory, this essay examines how characteristics of external feedback can interact with motivations to influence continued participation intention. The three essays are expected to enrich the information systems literature by providing new insights on various factors that can enhance engagement of IS professionals in the open source domain. The essays also contribute to the IS literature by applying the job characteristics model, social exchange theory, and signaling theory in the context of open source development

The nexus between Asian and US short-term financing rate

Purpose: The purpose of this paper is to examine the nexus between Asian and the US short-term financing rates and compare them between pre- and post-Asian financial crisis. Design/methodology/approach: The short-term financing rate is used in the estimation by employing two-stage cointegration test. Findings: The result of the empirical study shows several outcomes; the short-term financing rates among the selected Asian countries are not highly correlated during pre-crisis period, but the rates become strongly associated during the post-crisis period. The US financing rate has significant influence on the Asian rate during both periods. Asian financing rates are not integrated by the influence of the USA, rather regional cooperation and financial initiatives lead the regional financing rate to be integrated. Originality/value: The empirical finding of the study offers significant policy implications for strengthening regional economic bonding and developing the financial systems. © 2019, Emerald Publishing Limited

The nexus between financial integration and real economy: Solow-growth model concept

This paper aims to investigate the nexus between financial integration and the real economy in ASEAN + 3 economies based on the concept of Solow-Growth Model. The equity indices as a proxy for financial markets are collected from each ASEAN + 3 members and are segmented between two periods; before and after the financial cooperation agreement period. The finding presents several outcomes; 1) no cointegration nexus is found in the system during the pre-agreement periods; 2) the markets are found cointegrated during the post-agreement period, 3) financial integration is found to influence the real sectors of ASEAN + 3 economies. Finally, this study offers policy implications to improve financial integration for stabilizing the real economy

Distributed Vector Gaussian Source-Coding And Distributed Hypothesis Testing

Distributed compression is desired in applications in which data is collected in a distributed manner by several sensors and information about the data is sent to a processing center, which uses these information to meet an end goal. In this work, we focus on two such applications: (1) distributed source coding and (2) distributed hypothesis testing. In distributed source coding, we determine the rate region of the vector Gaussian one-helper source-coding problem under a covariance matrix distortion constraint. The rate region is achieved by a simple scheme that separates the lossy vector quantization from the lossless spatial compression. We introduce a novel analysis technique, namely distortion projection. The converse is established by combining distortion projection with two other analysis techniques that have been employed in the past to obtain partial results for the problem. We also study an extension to a special case of the problem in which the primary source is a vector and the helper's observation is a scalar and consider separate distortion constraints on both sources. We provide an outer bound to the rate region of this problem and show that it is partially tight in general and completely tight in some nontrivial cases. In distributed hypothesis testing, we study a problem in which data is compressed distributively and sent to a detector that seeks to decide between two possible distributions for the data. The aim is to characterize all achievable en- coding rates and exponents of the type 2 error probability when the type 1 error probability is at most a fixed value. For related problems in distributed source coding, schemes based on random binning perform well and are often optimal. For distributed hypothesis testing, however, the use of binning is hindered by the fact that the overall error probability may be dominated by errors in the binning process. We show that despite this complication, binning is optimal for a class of problems in which the goal is to "test against conditional independence." We then use this optimality result to give an outer bound for a more general class of instances of the problem. We also extend the "test against independence" result of Ahlswede and Csisz´ r to the vector Gaussian case.

Drug repurposing against the store-operated calcium entry (SOCE) pathway and subsequent exploration of SOCE in oligodendrocyte progenitor cells

The store-operated calcium entry (SOCE) pathway is an important route for generating cytosolic Ca2+ signals that regulate a diverse array of biological processes. Abnormal SOCE seem to underlie several diseases that notably include allergy, inflammation, acute pancreatitis and cancer. Therefore, any modulator of this pathway is likely to have significant impact in cell biology under both normal and abnormal conditions. In this study, the FDA-approved drug library was screened for agents that share significant similarity in 3D shape and surface electrostatics with few, hitherto best-known inhibitors of SOCE. This has led to the identification of five drugs that showed dose- dependent inhibition of SOCE in cell-based assay, probably through blocking SOCE pathway extracellularly. Of these drugs, leflunomide and teriflunomide could suppress SOCE significantly at clinically-relevant doses and this provides for an additional mechanism towards the therapeutic utility of these drugs as immunosuppressants. Few more compounds from each of the 4 different pharmacological classes were further tested using cell-based methods to find agents with more potent SOCE-inhibitory potency. Three candidates with better potency namely trequinsin, roflumilast N-oxide and vidofludimus, were identified. Of these compounds, vidofludimus which is known to be an inhibitor of the dihydroorotate dehydrogenase (DHODH) enzyme, proved to be the most potent (IC50~1.4μM) SOCE inhibitor among all the drugs tested, inhibitor of SOCE as it could suppress SOCE significantly at nanomolar dose. Next, selected drugs identified with SOCE suppressive ability were evaluated against the proliferation of different lung cancer cells namely H520, H1752, and LK2. In agreement with previous studies with bona fide SOCE inhibitors, the chosen drugs significantly reduced proliferation of those lung cancer cells. Interestingly, the anti-proliferative activity of most of the selected drugs were observed at concentrations at which they could significantly inhibit SOCE identified in those lung cancer cells. Although the possible contribution of the inhibition of the known targets of these drugs towards their anti-proliferative activity could not be ruled out, it was nevertheless indicative of the fact that their SOCE-inhibitory property was definitely implicated. This, in agreement with existing literature, hinted towards the fact that SOCE can be targeted to achieve potential therapeutic benefit against lung cancer and other cancer cells of epithelial origins. Of the drugs identified at the early phase of the present work to possess SOCE suppressive ability, teriflunomide is approved for multiple sclerosis (MS) which is believed to be autoimmune origin. The pro-drug of teriflunomide is leflunomide which is approved for managing rheumatoid arthritis. Since oligodendrocytes progenitor cells (OPCs) play important role in MS due to their myelin forming ability upon differentiation, SOCE was characterized in OPCs using single cell Ca2+ imaging approach and effect of some SOCE inhibitory compounds were then evaluated for any role in OPC differentiation. Employing different biochemical and imaging methods, AnCoA4, a known SOCE blocker was found to promote differentiation of OPCs. This finding could help to identify new target to develop therapeutic for demyelinating diseases like MS.Yousef Jameel Cambridge Trust

Thermoreflectance for Contactless Sintering Characterization: From Metal Nanoparticles to Stretchable Conductors

Sintering metal nanoparticles is a crucial step to achieve printed conductors. It is important to characterize and monitor nanoparticle sintering for process optimization and control. Here, we demonstrate that frequency-domain thermoreflectance (FDTR), an optical pump-probe technique, can be used for non-contact, non-destructive process monitoring that is compatible with high-throughput printed electronics manufacturing, unlike traditional electrical resistance measurements. The thermal conductivity measured from FDTR agrees well with thermal conductivity calculated using Wiedemann-Franz law from electrical conductivity measurements. Measurement time is reduced to 12 s by choosing a small number of measurement frequencies instead of a full frequency sweep and measuring them simultaneously. A Monte Carlo simulation was performed to predict the possibility of further reducing measurement time. Understanding of the sintering process allows tailoring of materials properties as demonstrated here to create a novel stretchable conductor. Differently sintered layers are combined to achieve a desirable stretchability-conductivity profile

HIGH TEMPERATURE TRIBOLOGY PERFORMANCE of NICKEL ALLOYS under HELIUM ATMOSPHERE

Currently the health and well-being of the global society are affected by energy source efficiency, reliability and enviromental impact. Nuclear power is one of the realiable energy resources with low greenhouse gas emissions per unit energy generated. Findings from the current research directly result in more reliable and efficient nuclear power plants. The objective of this research is to systematically evaluate the tribological response of 800HT and 617 alloys at relevant reactor operating temperatures (700-950 °C) and in the presence of helium (He) coolant. This research aims to address the need for a clear and inclusive understanding of the tribological performance of Nickel (Ni) based alloys in high temperature (HT) gas cooled reactors HTGR/VHTR operational environment that will clarify the necessity of further enhancement in HT durability and environmental compatibility of tribological components operating in HTGR-He coolant. The fundamental knowledge in high temperature tribology, especially in controlled gas atmosphere is limited, mainly due to complexity of experimental tests and analytical/numerical methods. The present work is pushing the boundaries of in-situ multiscale (nano/micro/macro) characterization of tribological materials in air/non-air ambient conditions at very high temperatures through novel experimental setups (e.g., very high temperature tribometer and very high temperature nano-indenter, under controlled Helium conditions). Also, comprehensive surface layer composition studies using advanced electron microscopy and other material characterization techniques, provide insght into prevention and failure mechanisms. Using a custom-built high temperature tribometer, helium cooled reactor environment was simulated at room and 950 oC temperatures. Microscopy and chemical analyses are carried out to explain the tribological performance of the alloys. At elevated temperatures, both alloys show higher friction in helium, compared to air environment. Both alloys exhibit high wear resistance in all experimental conditions, except at high temperature helium environment. The formation of glazed and mechanically mixed layers of oxides were found to be important causes for the lower friction and wear in high temperature air atmosphere. The in-depth chemical analysis of the oxide layer using techniques like EDS, XRD, RAMAN and SIMS were performed to link the tribochemical aspects to the evolution of mechanical properties under contact. This work provides new knowledge in the form of scientific papers, technical reports, and presentations that benefits a wide range of communities, and individuals. Most importantly this work is showcasing the important tribological issues encountered in suture state-of-the-art nuclear reactors