1,769 research outputs found

    Venture Capital Funding for Information Technology Businesses

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    The success of new ventures can hinge on obtaining venture capital (VC) funding. Virtually every successful IT venture has depended on VC funding early in its history. However, obtaining venture capital is difficult. Unlike earlier studies on VC funding that consider new ventures to be homogeneous, this study seeks to identify factors that VCs consider when they make funding decisions for IT ventures. Building on prior research in the area of agency and business risk, we develop a theoretical model that draws on work in finance and entrepreneurship. The model suggests that VCs consider two types of risk: business risk and agency risk. The relative importance of these two types of risk may be different across industries. We test this model using data from 139 business plans for IT startups that were considered for funding by VCs. Traditional structural equation modeling (SEM) does not accommodate non-normal data or dichotomous outcome variables. Using the Robust Weighted Least Squares approach, we test our model with non-normal data and dichotomous outcomes. In addition, we use Tetrad analysis to check model fit against alternative models, floor and ceiling analysis to test sample frame validity, relative effect size comparison to test relative elasticity of effects, and a Monte Carlo estimation approach to test overall model power and power of individual paths. We find that business risk is an important factor in start-up funding for IT ventures. We do not find agency risk to be an important consideration in start-up funding for IT ventures

    Integrative Approach for a Transformative Freshman-Level STEM Curriculum

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    In 2014 Wesley College adopted a unified undergraduate program of evidence-based high-impact teaching practices. Through foundation and federal and state grant support, the college completely revised its academic core curriculum and strengthened its academic support structures by including a comprehensive early alert system for at-risk students. In this core, science, technology, engineering, and mathematics (STEM) faculty developed fresh manifestations of integrated concept-based introductory courses and revised upper-division STEM courses around student-centered learning. STEM majors can participate in specifically designed paid undergraduate research experiences in directed research elective courses. Such a college-wide multi-tiered approach results in institutional cultural change

    Compensation of B-L charge of matter with relic sneutrinos

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    We consider massless gauge boson connected to B-L charge with and without compensation to complete the investigation of the gauging of B and L charges. Relic sneutrinos predicted by SUSY and composite models may compensate B-L charge of matter. As a consequence of the possible compensation mechanism we have shown that the available experimental data admit the range of the B-L interaction constant, 10^{-29} < {\alpha}_{B-L} < 10^{-12}, in addition to {\alpha}_{B-L} < 10^{-49} obtained without compensation.Comment: 6 page

    Self-assembling multidomain peptides tailor biological responses through biphasic release

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    Delivery of small molecules and drugs to tissues is a mainstay of several tissue engineering strategies. Next generation treatments focused on localized drug delivery offer a more effective means in dealing with refractory healing when compared to systemic approaches. Here we describe a novel multidomain peptide hydrogel that capitalizes on synthetic peptide chemistry, supramolecular self-assembly and cytokine delivery to tailor biological responses. This material is biomimetic, shows shear stress recovery and offers a nanofibrous matrix that sequesters cytokines. The biphasic pattern of cytokine release results in the spatio-temporal activation of THP-1 monocytes and macrophages. Furthermore, macrophage–material interactions are promoted without generation of a proinflammatory environment. Subcutaneous implantation of injectable scaffolds showed a marked increase in macrophage infiltration and polarization dictated by cytokine loading as early as 3 days, with complete scaffold resorption by day 14. Macrophage interaction and response to the peptide composite facilitated the (i) recruitment of monocytes/macrophages, (ii) sustained residence of immune cells until degradation, and (iii) promotion of a pro-resolution M2 environment. Our results suggest the potential use of this injectable cytokine loaded hydrogel scaffold in a variety of tissue engineering applications

    Algorithm for normal random numbers

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    We propose a simple algorithm for generating normally distributed pseudo random numbers. The algorithm simulates N molecules that exchange energy among themselves following a simple stochastic rule. We prove that the system is ergodic, and that a Maxwell like distribution that may be used as a source of normally distributed random deviates follows when N tends to infinity. The algorithm passes various performance tests, including Monte Carlo simulation of a finite 2D Ising model using Wolff's algorithm. It only requires four simple lines of computer code, and is approximately ten times faster than the Box-Muller algorithm.Comment: 5 pages, 3 encapsulated Postscript Figures. Submitted to Phys.Rev.Letters. For related work, see http://pipe.unizar.es/~jf

    Stress and stressors experienced by the parents of high-risk neonates admitted in neonatal intensive care unit: Systematic review and meta-analysis evidence available from India

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    The aim of the systematic review and meta-analysis is to determine the stress and stressors experienced by the parents of high-risk neonates admitted to the neonatal intensive care unit (NICU) in India. We included both quantitative and qualitative studies. The Joanna Briggs Institute Critical Appraisal Checklist and Critical Appraisal Skill Programme checklist were used to assess the quality of included studies. A systematic search was conducted in PubMed, EMBASE, SCOPUS, EBSCOhost, Web of Science, ProQuest, Microsoft Academic, DOAJ, Indian Citation Index, and J-Gate to identify relevant studies. Additionally, online hand searching was performed on Indian websites of relevant institutions, women and child health departments, repositories, registries, and paediatric journals. Twelve of the 21 quantitative studies found that maternal stress was higher than fathers due to the separation from their babies and the medical condition of the neonate. One qualitative study reported that financial burden, alterations in the parenting role, and concern over domestic issues are significant causes of fathers' stress. A meta-analysis of the included studies assessed the prevalence of maternal, paternal, and parental stress and reported that mothers experienced higher stress levels than fathers across all subscales. The most typical stressors for parents were changes in neonatal looks, behaviour, and altered parental roles. Beyond the immediate NICU care and interactions, other triggering factors of stress among parents must be considered to design multicomponent interventions in a local (Indian) context. Moreover, parental psychological support and regular counselling can be incorporated into the standard neonatal intensive care policy

    Enhancement of β-phase in PVDF films embedded with ferromagnetic Gd<sub>5</sub>Si<sub>4</sub> nanoparticles for piezoelectric energy harvesting

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    Self-polarized Gd5Si4-polyvinylidene fluoride (PVDF) nanocomposite films have been synthesized via a facile phase-inversion technique. For the 5 wt% Gd5Si4-PVDF films, the enhancement of the piezoelectric β-phase and crystallinity are confirmed using Fourier transform infrared (FTIR) spectroscopy (phase fraction, Fβ, of 81% as compared to 49% for pristine PVDF) and differential scanning calorimetry (crystallinity, ΔXc, of 58% as compared to 46% for pristine PVDF), respectively. The Gd5Si4 magnetic nanoparticles, prepared using high-energy ball milling were characterized using Dynamic Light Scattering and Vibrating Sample Magnetometry (VSM) to reveal a particle size of ∼470 nm with a high magnetization of 11 emu/g. The VSM analysis of free-standing Gd5Si4-PVDF films revealed that while the pristine PVDF membrane shows weak diamagnetic behavior, the Gd5Si4-PVDF films loaded at 2.5 wt% and 5 wt% Gd5Si4 show enhanced ferromagnetic behavior with paramagnetic contribution from Gd5Si3 phase. The interfacial interactions between Gd5Si4 and PVDF results in the preferential crystallization of the β-phase as confirmed via the shift in the CH2 asymmetric and symmetric stretching vibrations in the FTIR. These results confirm the magnetic Gd5Si4 nanoparticles embedded in the PVDF membrane lead to an increased β-phase fraction, which paves the way for future efficient energy harvesting applications using a combination of magnetic and piezoelectric effects

    Sympathetic and hemodynamic responses to exercise in heart failure with preserved ejection fraction

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    Excessive sympathetic activity during exercise causes heightened peripheral vasoconstriction, which can reduce oxygen delivery to active muscles, resulting in exercise intolerance. Although both patients suffering from heart failure with preserved and reduced ejection fraction (HFpEF and HFrEF, respectively) exhibit reduced exercise capacity, accumulating evidence suggests that the underlying pathophysiology may be different between these two conditions. Unlike HFrEF, which is characterized by cardiac dysfunction with lower peak oxygen uptake, exercise intolerance in HFpEF appears to be predominantly attributed to peripheral limitations involving inadequate vasoconstriction rather than cardiac limitations. However, the relationship between systemic hemodynamics and the sympathetic neural response during exercise in HFpEF is less clear. This mini review summarizes the current knowledge on the sympathetic (i.e., muscle sympathetic nerve activity, plasma norepinephrine concentration) and hemodynamic (i.e., blood pressure, limb blood flow) responses to dynamic and static exercise in HFpEF compared to HFrEF, as well as non-HF controls. We also discuss the potential of a relationship between sympathetic over-activation and vasoconstriction leading to exercise intolerance in HFpEF. The limited body of literature indicates that higher peripheral vascular resistance, perhaps secondary to excessive sympathetically mediated vasoconstrictor discharge compared to non-HF and HFrEF, drives exercise in HFpEF. Excessive vasoconstriction also may primarily account for over elevations in blood pressure and concomitant limitations in skeletal muscle blood flow during dynamic exercise, resulting in exercise intolerance. Conversely, during static exercise, HFpEF exhibit relatively normal sympathetic neural reactivity compared to non-HF, suggesting that other mechanisms beyond sympathetic vasoconstriction dictate exercise intolerance in HFpEF
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