Miracle-dz/UniFAR-FTUs huggingface dataset:
Matrix Stiffness Regulates Glial Cell Morphology and Differentiation

MATRIX STIFFNESS REGULATES GLIAL CELL MORPHOLOGY AND DIFFERENTIATION By Mateusz M. Urbanski Advisor: Carmen Melendez-Vasquez Studies from our laboratory have shown that inhibition of non-muscle myosin II (NMII) activity has opposite effects on the formation of myelin by oligodendrocytes (OL), the myelinating glia of the central nervous system (CNS) and Schwann cells (SC), which perform the same function in the peripheral nervous system (PNS). The decrease of NMII activity in SC impairs their ability to establish polarity and myelinate, while its inhibition in OL enhances process branching and increases the amount of myelin formed in vitro an in vivo. A growing number of studies have shown that NMII also plays a role in the ability of cells to sense and respond to the stiffness of the surrounding extracellular matrix (ECM). In the PNS, the ECM consists of a dense SC-secreted basal lamina, which displays significantly higher rigidity than the more loosely organized CNS matrix. In order to evaluate whether the opposing effects of inhibiting NMII in glial cell differentiation and myelination are partly the result of NMII-mediated sensing of ECM stiffness, we have grown cultures of primary rat OL and SC on variable rigidity polyacrylamide matrices coated with covalently bound ECM proteins. We found that stiffer matrices inhibit OL branching as well as their expression of differentiation markers, and that these effects are correlated with
R&D Team Diversity and Performance in Hypercompetitive Environments

Research summary: This article examines the effects of an R&D team's composition on its performance outcomes in hypercompetition. The fundamental feature of firms in hypercompetitive settings is that they are constantly challenged to improve their competitiveness in a relentless race to outperform one another. Analyzing a unique data set from the Formula 1 motorsport racing industry, we find an inverse U-shaped relationship between team diversity in task-related experience and performance an important result that diverges from well-established theories developed in more stable environments. Fundamentally, we show that the role of R&D team experience diversity varies depending on the size of the organizations in which R&D teams operate. While we find a moderating effect for firm age, this effect is not as robust as that of firm size. Managerial summary: This article examines the relationship between R&D team composition and performance in fast-moving environments. Firms in these environments are constantly challenged to improve their competitiveness by outperforming one another. Analyzing a unique data set from the Formula 1 motorsport racing industry, we find that a team's diversity in job-related experience increases its performance up to a certain extent. Once R&D teams become too diverse, performance decreases because communication and coordination become more difficult. We also show that the role of R&D team diversity varies depending on the size of the organizations in which R&D teams operate. Overall, our findings provide several novel implications for the strategy, innovation, and team literatures. Copyright © 2016 John Wiley & Sons, Ltd.
Essays on institutional investors, central banks and asset pricing

The objective of this dissertation is to investigate the impact of important market participants such as Mutual Funds, Hedge Funds and the Federal Reserve Bank on the equilibrium equity premium, risk free rate and asset volatility and to analyze the effect of these institutions on risk shifting, portfolio allocation and financial stability. Specific features of institutional investors and central banks as well as their role in financial markets are reviewed and analyzed in Chapter 1. In Chapter 2, it is shown that the competitive pressure to beat a benchmark may induce institutional trading behavior that exposes retail investors to tail risk. In our model, institutional investors are different from a retail investor because they derive higher utility when they outperform the benchmark. This forces institutions to take on leverage to over-invest in the benchmark. Institutions execute fire sales when the benchmark asset experiences negative shocks. This behavior increases market volatility, raising the tail risk exposure of the retail investor. Nevertheless, ex-post, tail risk is only short lived, all investors survive in the long run under standard conditions, and the most patient investor dominates in the sense that she has the highest con-
Research Note: The Influence of Recommendations and Consumer Reviews on Evaluations of Websites

Recommendations and consumer reviews are universally acknowledged as significant features of a business-to-consumer website. However, because of the well-documented obstacles to measuring the causal impact of these artifacts, there is still a lack of empirical evidence demonstrating their influence on two important outcome variables in the shopping context: perceived usefulness and social presence. To test the existence of a causal link between information technology (IT)-enabled support for the provision of recommendations and consumer reviews on the usefulness and social presence of the website, this study employs a novel approach to generate the experimental conditions by filtering the content of Amazon.com in real time. The results show that the provision of recommendations and consumer reviews increases both the usefulness and social presence of the website.
Selective Information Sharing of a Multi-Product Manufacturer

This paper identifies strategic reasons for a multi-product manufacturer to selectively share information with its different suppliers. The traditional result in strategic ex-post disclosure settings is that a manufacturer wants to withhold good news from its suppliers, so that the suppliers will not increase their input prices, implementing the seminal "unraveling" result leading to full disclosure. In contrast, on account of the interdependencies arising from the multi-supplier-multi-product structure, we find that the manufacturer always discloses its information to one supplier but may concurrently withhold the same information from a second supplier, engaging in selective information sharing. Selective information sharing in this setting arises because a price change of a supplier affects multiple products that require the same input and affects the pricing decision the other supplier that delivers a complementary input, creating trade-offs in the manufacturer's disclosure preferences. Selective information sharing can arise even when the suppliers can exchange information among themselves.
Differences in the social networks of African American men who have sex with men only and those who have sex with men and women.

OBJECTIVES We compared social network characteristics of African American men who have sex with men only (MSMO) with social network characteristics of African American men who have sex with men and women (MSMW). METHODS Study participants were 234 African American men who have sex with men who completed a baseline social network assessment for a pilot behavioral HIV prevention intervention in Baltimore, Maryland, from 2006 through 2009. We surveyed the men to elicit the characteristics of their social networks, and we used logistic regression models to assess differences in network characteristics. RESULTS MSMO were significantly more likely than were MSMW to be HIV-positive (52% vs 31%). We found no differences between MSMO and MSMW in the size of kin networks or emotional and material support networks. MSMW had denser sexual networks, reported more concurrent and exchange partners, used condoms with more sexual partners, and reported interaction with a larger number of sexual partners at least once a week. CONCLUSIONS Although there were many similarities in the social and sexual network characteristics of MSMO and MSMW, differences did exist. HIV prevention interventions should address the unique needs of African American MSMW.
An Effective and Robust Single Image Dehazing Method Using the Dark Channel Prior

In this paper, we propose a single image dehazing method aiming at addressing the inherent limitations of the extensively employed dark channel prior (DCP). More concretely, we introduce the Gaussian mixture model (GMM) to segment the input hazy image into scenes based on the haze density feature map. With the segmentation results, combined with the proposed sky region detection method, we can effectively recognize the sky region where the DCP cannot well handle this. On the basis of sky region detection, we then present an improved global atmospheric light estimation method to increase the estimation accuracy of the atmospheric light. Further, we present a multi-scale fusion-based strategy to obtain the transmission map based on DCP, which can significantly reduce the blocking artifacts of the transmission map. To further rectify the error-prone transmission within the sky region, an adaptive sky region transmission correction method is also presented. Finally, due to the segmentation-blindness of GMM, we adopt the guided total variation (GTV) to tackle this problem while eliminating the extensive texture details contained in the transmission map. Experimental results verify the power of our method and show its superiority over several state-of-the-art methods.
A new deramping algorithm for airborne squint-mode spotlight SAR data processing

This paper presents a new airborne squint-mode spotlight SAR data focusing algorithm based on a two-step processing strategy that combines the advantages of the efficiency of spectral analysis (SPECAN) algorithm and the precision of wavenumber domain (WD) algorithm. The first step of the proposed algorithm implements a modified SPECAN processing to the range compressed echo signal. This operation can eliminate azimuth spectrum folding effect and migrate and scale the azimuth data support. Then the residual and precision focusing of the SAR data is achieved by applying the WD algorithm requiring some modifications and implemented in the frequency domain. Finally, experiments carried out on simulated data confirm the validity of the presented approach.
Switchable S = 1/2 and J = 1/2 Rashba bands in ferroelectric halide perovskites

Significance Manipulation of electron spins is an important research subject to achieve breakthroughs in current electronics. The Rashba effect is the spin energy level splitting due to broken inversion symmetry and spin–orbit coupling, and the controllability of Rashba splitting is crucial to spin manipulation. Here, we report a theoretical investigation of Rashba band splitting in ferroelectric halide perovskite materials. Since the polarization direction in ferroelectric materials can be switched by external electric fields, Rashba splitting can be controlled conveniently in these materials. Interestingly, ferroelctric polarizations give rise to two distinct Rashba bands of contrasting orbital and spin characters. Taking advantage of the unique band characteristics, these materials prove promising candidates for the switchable Rashba effect. The Rashba effect is spin degeneracy lift originated from spin–orbit coupling under inversion symmetry breaking and has been intensively studied for spintronics applications. However, easily implementable methods and corresponding materials for directional controls of Rashba splitting are still lacking. Here, we propose organic–inorganic hybrid metal halide perovskites as 3D Rashba systems driven by bulk ferroelectricity. In these materials, it is shown that the helical direction of the angular momentum texture in the Rashba band can be controlled by external electric fields via ferroelectric switching. Our tight-binding analysis and first-principles calculations indicate that and Rashba bands directly coupled to ferroelectric polarization emerge at the valence and conduction band edges, respectively. The coexistence of two contrasting Rashba bands having different compositions of the spin and orbital angular momentum is a distinctive feature of these materials. With recent experimental evidence for the ferroelectric response, the halide perovskites will be, to our knowledge, the first practical realization of the ferroelectric-coupled Rashba effect, suggesting novel applications to spintronic devices.
Good point sets and corresponding weights for bivariate discrete least squares approximation

An algorithm is presented to compute good point sets and weights for discrete least squares polynomial approximation on a geometry R 2 . The criterion that is used is the minimisation of the Lebesgue constant of the corresponding least squares operator. In order to approximate the Lebesgue constant, we evaluate the Lebesgue function in a point set generated by a refinement method that is based on Delaunay triangulation. The algorithm is greedy in the sense that points are added where the Lebesgue function is largest. It also uses a new updating algorithm for the weights such that the corresponding Lebesgue constant is made smaller. Advantages of the method are that it works for a general geometry and that the point sets are nested. Numerical experiments show that the Lebesgue constant corresponding to the least squares operator is low and grows slower than polynomially in function of the total degree of the polynomial approximation space. It follows that the computed points are point sets of a weakly admissible mesh (WAM).
Development of a novel one-step production system for injectable liposomes under GMP

Abstract There are few methods available for injectable liposome production under good manufacturing practices (GMP). Injectable liposome production processes under GMP generally consist of liposome formation, size homogenization, organic solvent removal, liposome concentration control and sterilization. However, these complicated and separate processes make it difficult to maintain scalability, reproducibility and sterility. To overcome these limitations, we developed a novel one-step in-line closed liposome production system that integrated all production processes by combining the in-line thermal mixing device with modified counterflow dialysis. To validate the system, we produced liposomal cyclosporine A (Lipo-CsA) and lyophilized the liposomes. The three independent pilot batches were highly reproducible and passed the quality specifications for injectable drugs, demonstrating that this system could be used under GMP. The accelerated stability test suggested that the liposomes would be stable in long-term storage. This one-step system facilitates a fully automated and unattended production of injectable liposomes under GMP.
Modulation of the Human Kv1.5 Channel by Protein Kinase C Activation: Role of the Kvβ1.2 Subunit

Kv1.5 is the principal molecular component of IKur, an atrial-specific K+ current in human myocytes that is suppressed by activation of protein kinase C (PKC). We examined the effect of phorbol 12-myristate 13-acetate (PMA), a direct activator of PKC, on Kv1.5 current. Although PMA had minimal effect when Kv1.5 was expressed alone, K+ currents derived from coexpression of Kvβ1. 2 (but not another closely related β subunit, Kvβ1.3) with Kv1.5 were markedly reduced by PMA, associated with a small depolarizing shift in the voltage dependence of channel activation. Additional experiments with an inactive stereoisomer, 4α-PMA, and the PKC inhibitor chelerythrine indicated that the effects of PMA were mediated by PKC activation. Assembly of Kv1.5 in vivo with both β subunits was demonstrated, and all three K+ channel proteins were substrates for phosphorylation by PKC. These results demonstrate that coexpression of Kvβ1. 2 enhances the response of Kv1.5 to PKC activation and that direct phosphorylation of K+ channel subunits is a potential molecular basis for the effect. Furthermore, they suggest that Kvβ1. 2 may be a component of the IKur complex in human atrium.
Midkine Inhibits Caspase‐Dependent Apoptosis via the Activation of Mitogen‐Activated Protein Kinase and Phosphatidylinositol 3‐Kinase in Cultured Neurons

Midkine (MK) is a new member of the heparin-binding neurotrophic factor family. MK plays important roles in development and carcinogenesis and has several important biological effects, including promotion of neurite extension and neuronal survival. However, the mechanism by which MK exerts its neurotrophic actions on neurons has not been elucidated to date. We have established an apoptosis induction system by serum deprivation in primary neuronal cultures isolated from mouse cerebral cortices. Neuronal apoptosis induced by serum deprivation was accompanied by the activation of caspase-3. MK, when added into the culture medium, inhibited the induction of apoptosis and activation of caspase-3 in a dose-dependent manner. Extracellular signal-regulated kinase (ERK) and Akt were not activated by serum deprivation, whereas ERK and Akt were rapidly activated by addition of MK. In addition, the trophic actions of MK of suppressing apoptosis and suppressing the activation of caspase-3 were abolished by concomitant treatment with PD98059, a specific inhibitor of mitogen-activated protein kinase kinase, and with wort-mannin or LY294002, specific inhibitors of phosphatidyl-inositol 3-kinase (PI 3-kinase). These PI 3-kinase inhibitors also inhibited the activation of ERK in response to MK, demonstrating a link between ERK and the caspase-3 pathway that is modulated by the PI 3-kinase activation. These results indicate that the ERK cascade plays a central role in MK-mediated neuronal survival via inhibition of caspase-3 activation.
Students' personal networks in virtual and personal learning environments: a case study in higher education using learning analytics approach

The main objective of this paper is to analyse the effect of the affordances of a virtual learning environment and a personal learning environment (PLE) in the configuration of the students' personal networks in a higher education context. The results are discussed in light of the adaptation of the students to the learning network made up by two undergraduate, inter-university and online courses. Besides, we also examine the influence of this effect in the learning process. The findings reflect the effectiveness of a PLE for facilitating student participation and for assisting students in the creation of larger and more balanced personal networks with richer social capital. However, the findings do not provide evidences about a difference in the learning performance between the two environments. From a methodological point of view, this paper serves as an illustration of the analysis of personal networks on digital data collected from technology-enhanced learning environments.
Diminished-One Modulo 2n+1 Adder Design

This paper presents two new design methodologies for modulo 2/sup n/+1 addition in the diminished-one number system. The first design methodology leads to carry look-ahead, whereas the second to parallel-prefix adder implementations. VLSI realizations of the proposed circuits in a standard-cell technology are utilized for quantitative comparisons against the existing solutions. Our results indicate that the proposed carry look-ahead adders are area and time efficient for small values of n, while for the rest values of n the proposed parallel-prefix adders are considerably faster than any other already known in the open literature.
Shopping Involvement In Online Buyi Ng Strategic study with reference to antecedents and consequences

An increasing number and variety of firms and organizations are exploiting and creating we based business opportunities. Parallel, several researches has been conducted on business to consumer (B2C) e-retailing (Liu and Arnett, 2000; Collier and Bienstock, 2006; Deng et al., 2010. However, in a country like India where the culture of E retailing in drastically new , but the potential is huge there is a significant need to determine the derivers for customer satisfaction, trust and repeat purchase. Maintaining customer repeatpurchase intention and avoiding significant switching behavior to sustain operations and gain competitive advantage is thus important for Eretailers (Kuo and Hu, 2012). This paper aims at investigating the impact of convenience, Perceive Risk, Variety, Shopping experience and Price on the Shopping involvement of the online customers. Moreover, the effect of shopping involvement and customer satisfaction is being evaluated on repeat purchase intensions of the customers. Based on the research findings, this study makes suggestions regarding management strategies typically for retailers who see Indian customers as a prospect for ERetailing.
INVESTMENT DECISION AND FINANCIAL CONSTRAINTS: EMPIRICAL STUDY ON INDONESIAN STOCK EXCHANGE

This research aims to test the sensitivity level of liquidity and invesment opportunity to invesment decision between non-financially constrained and financially constrained firms. Sample in this research is the firm of non finance which enlist in Indonesia Stock Exchange from period 2003 to 2007, obtained sample 136 firms with 680 observations. Result of research refer that liquidity and invesment opportunity have an influence on positive to invesment decision. Liquidity is more sensitive to invesment decision for financially constrained firms. Invesment opportunity is more sensitive to invesment decision for non financially constrained JEL Classification : E22, G32, O16. Key words : Investment decision, liquidity, financially constraint.
Late starters or excluded generations? A cohort analysis of catch up in home ownership in England

We investigate whether initial differences in speed of entry into homeownership lead to longlasting differences in ownership between generations. Our data span nearly forty years and multiple cycles of England’s very volatile house prices. We document that ownership rates at thirty have differed substantially, with a significant negative association with prices. To assess the persistence of these differences we use synthetic cohort methods. Measurement error problems – attenuation and other biases - complicate the analysis. Two methods of dealing with this both indicate that cohorts with low ownership rates at thirty close about 80% of the ownership gap by forty.
Forest Height Estimation by Means of Pol-InSAR Data Inversion: The Role of the Vertical Wavenumber

This paper examines the multifaceted effect of the effective spatial baseline, as expressed through the vertical (interferometric) wavenumber, on the inversion of forest height from polarimetric interferometric synthetic aperture radar (Pol-InSAR) data. First, the role of the vertical wavenumber in relating forest height to the interferometric (volume) coherence is introduced. Through the review of the forest height inversion from Pol-InSAR data, the effect of the vertical wavenumber on the inversion performance is evaluated. The selection of optimum with respect to forest height inversion performance, vertical wavenumbers is discussed. The impact of the acquisition geometry and terrain slopes on the vertical wavenumber and their consideration in the inversion methodology is addressed. The individual effects discussed are demonstrated by means of airborne repeat pass Pol-InSAR acquisitions in L- and P-band acquired over different forest conditions, including a boreal, a temperate, and a tropical forest test site. The achieved forest height inversion performance is validated against reference height data derived from airborne LIDAR acquisitions.