838 research outputs found

    Scientometric approach of productivity in scholarly economics and business

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    Some scientometric studies attempt to explain the factors affecting a country’s scientific output, which is usually measured by proxy variables such as the number of articles and citations in internationally-renowned journals. This paper highlights the main drivers for scientific output in economics and business, namely, financing of education and research, population size, the number of scholarly journals and English as the official language. We use multiple OLS regressions and data provided by Web of Knowledge and the World Bank covering 56 nations. The study also highlights the relationship between scientific output and the efficiency in using the research funding. The rankings of sample countries show that there is a learning process at national level, the output being doubled by efficiency

    Collagen-based biomaterials with possible therapeutic effects

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    Epidermolysis bullosa (EB) is a rare, serious genetic disease, incurable through the current means. Apart from this initial definition, there was later some ease in the definition of the disease, including the manifestations of toxic epidermal necrolysis and Stevens Johnson syndrome in this entity. In medical practice, there are cases that do not overlap with the description in the literature, thus the treatment must be adapted and personalized to the particularities. We present the case of a female new-born, with de novo mutation for the early-onset antenatal epidermolysis and our personalized therapeutic management, based on collagen from bovine corneas by enzymatic process. The histological examination showed that the collagen membranes serve as a support for the epithelial cells that formed a surface monolayer after 48 hours. Therefore. this case report shows that collagen-based biomaterials could be used to accelerate the dermal-epidermal healing in various conditions of the child, such as Stevens Johnson syndrome, bullous epidermolysis and widespread burns

    Impact of risk factors on the evolution of severe acute pancreatitis

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    Introduction. Severe acute pancreatitis (SAP) is an acute inflammatory condition of the pancreas with increasing incidence and mortality rates in recent years. The aim of this study was to evaluate the impact of age, comorbidities, and different scoring systems on the complications and outcomes of SAP. Materials and Methods. A retrospective study was conducted on 161 patients diagnosed and treated for SAP at the Bucharest University Hospital in the intensive care unit (ICU), in the period 2014-2021. The impact of risk factors for the development of SAP, occurrence of complications (respiratory, cardiac, etc.), length of hospital stays and mortality was analyzed using several scores (BISAP, Ranson, Apache II and SOFA) or modified computed tomography severity index. Preexisting chronic conditions were assessed using the Charlson Comorbidity Index (CCI). Multivariate statistics and non-parametric univariate were calculated in statistical analysis. Odds ratios with 95% confidence intervals were used. Results. Risk factors such as age, diet, medication, alcohol consumption, genetic factors and patient comorbidities contribute significantly to the development of a severe form of acute pancreatitis with critical course and high mortality. Conclusions. In our study, CCI was the most important factor correlated with death and duration of ICU treatment

    Biocompatibility Study of CoCrMoSi k Original Alloy Variants

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    The study follow the improvement of properties of cobalt base alloys, used in medical applications. This scope targeted the obtaining of alloys with friendly biological interactions to human body. If the original variants of CoCrMoSi k (k = 4, 5, 6, 7) alloys don't subjected to the criteria of biological acceptance from animal body, these don't be placed in live body, indifferent the adequacy of the biomaterials properties. Realization of the original alloy variants must consider and the possibility to appear the base pathophysiological phenomena, with determine or not their safety on long time (generate of thrombosis, inflammation, infection and / or inducing and causing neoplasms)

    Enhancement of bone consolidation using high-frequency pulsed electromagnetic fields (HF-PEMFs): An experimental study on rats

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    In vitro studies showed that high-frequency pulsed electromagnetic fields (HF-PEMFs) increase the activity/expression of early and late osteogenic markers and enhance bone mineralization. The main aim of this study was to investigate the in vivo effects of HF-PEMFs on fracture healing using a rat model. A femur fracture was established by surgery in 20 male Wistar rats. Titanium nails were implanted to reduce and stabilize the fracture. After surgery, 20 rats were equally divided into untreated control and treated group (from the first postoperative day HF-PEMFs at 400 pulses/sec [pps] were applied for 10 minutes/day, for two weeks). Quantitative and qualitative assessment of bone formation was made at two and eight weeks following surgery and included morphological and histological analysis, serological analysis by ELISA, micro-computed tomography (micro-CT), and three-point bending test. At two weeks in HF-PEMF group, soft callus was at a more advanced fibrocartilaginous stage and the bone volume/total tissue volume (BV/TV) ratio in the callus area was significantly higher compared to control group (p = 0.047). Serum concentration of alkaline phosphatase (ALP) and osteocalcin (OC) was significantly higher in HF-PEMF group (ALP p = 0.026, OC p = 0.006) as well as the mechanical strength of femurs (p = 0.03). At eight weeks, femurs from HF-PEMF group had a completely formed woven bone with dense trabeculae, active bone marrow, and had a significantly higher BV/TV ratio compared to control (p = 0.01). HF-PEMFs applied from the first postoperative day, 10 minutes/day for two weeks, enhance bone consolidation in rats, especially in the early phase of fracture healing

    Species diversity, host preference and arbovirus detection of Culicoides (Diptera: Ceratopogonidae) in south-eastern Serbia

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    BackgroundCulicoides (Diptera: Ceratopogonidae) is a genus of small biting midges (also known as no-see ums) that currently includes 1368 described species. They are proven or suspected vectors for important pathogens affecting animals such as bluetongue virus (BTV) and Schmallenberg virus (SBV). Currently little information is available on the species of Culicoides present in Serbia. Thus, the aim of this study was to examine species diversity, host preference and the presence of BTV and SBV RNA in Culicoides from the Stara Planina Nature Park in south-eastern Serbia.ResultsIn total 19,887 individual Culicoides were collected during three nights of trapping at two farm sites and pooled into six groups (Obsoletus group, Pulicaris group, Others group and further each group according to the blood-feeding status to freshly engorged and non-engorged). Species identification was done on subsamples of 592 individual Culicoides specimens by morphological and molecular methods (MALDI-TOF mass spectrometry and PCR/sequencing). At least 22 Culicoides species were detected. Four animal species (cow, sheep, goat and common blackbird) as well as humans were identified as hosts of Culicoides biting midges. The screening of 8291 Culicoides specimens in 99 pools for the presence of BTV and SBV RNA by reverse-transcription quantitative PCR were negative.ConclusionsThe biodiversity of Culicoides species in the natural reserve Stara Planina was high with at least 22 species present. The presence of C. imicola Kieffer was not recorded in this area. Culicoides showed opportunistic feeding behaviour as determined by host preference. The absence of SBV and BTV viral RNA correlates with the absence of clinical disease in the field during the time of sampling. These data are the direct outcome of a training programme within the Institutional Partnership Project AMSAR: Arbovirus monitoring, research and surveillance-capacity building on mosquitoes and biting midges funded by the programme SCOPES of the Swiss National Science Foundation

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

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    One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI
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