Miracle-dz/UniFAR-FTUs huggingface dataset:
Clinical outcomes with Preoperative and Postoperative Start of Thromboprophylxis in Total Hip Arthroplasty

Chemical thromboprophylaxis in total hip arthroplasty (THA) may increase surgical site bleeding. The drug dose and timing of such therapy is therefore important. We studied two cohorts of 298 and 301 patients undergoing THA. The first group received their first dose of dalteparin sodium 5000 IU subcutaneously the evening before surgery and the second group a half dose six hours postoperatively, followed by 5000 units daily in both groups. Blood loss was reduced by 146ml from 1230 ml to 1084 ml (p<0.001) with postoperative prophylaxis alone. The number of patients receiving blood transfusion decreased from 53% to 35% (p=0.001), and the use of transfused packed red blood cells was reduced from 1.25 to 0.83 units per patient (p=0.001). The overall rates of non-vascular complications 6 months after surgery were 12% and 11%, bleeding related events 6.0% and 4.0%, and thromboembolic related events were 2.0% and 2.3% in the preoperative and the postoperative cohorts. Two patients died in the preoperative group and one in the postoperative group due to venous and arterial thromboembolism. This study show that 2500 IU dose of dalteparin started 6 hours after surgery significantly reduced blood loss and transfusions compared to 5000 IU dalteparin injected 12 hours before surgery. Few thromboembolic events occurred, and these were equally distributed.
Implementing tidal and gravitational wave energy losses in few-body codes: A fast and easy drag force model

We present a drag force model for evolving chaotic few-body interactions with the inclusion of orbital energy losses, such as tidal dissipation and gravitational wave (GW) emission. The main effect from such losses is the formation of two-body captures, that for compact objects result in GW mergers, and for stars lead to either compact binaries, mergers or disruptions. Studying the inclusion of energy loss terms in few-body interactions is therefore likely to be important for modeling and understanding the variety of transients that soon will be observed by current and upcoming surveys. However, including especially tides in few-body codes has been shown to be technically difficult and computationally heavy, which has lead to very few systematic tidal studies. In this paper we derive a drag force term that can be used to model the effects from tidal, as well as other, energy losses in few-body interactions, if the two-body orbit averaged energy loss is known a priori. This drag force model is very fast to evolve, and gives results in agreement with other approaches, including the impulsive and affine tide approximations.
Empirical relationship ML-MD for the volcanic area of Mt. Etna (Italy)Empirical relationship ML-MD for the volcanic area of Mt. Etna (Italy)

Studies on seismicity at Mt. Etna are of extreme importance for the high seismic and volcanic risk which characterizes the area. In this region, seismic events are mainly located at less than 5 km b.s.l. depth, producing arrivals with medium-to low-frequency content and/or complicated signatures at stations just a few kilometers distant from the epicentral area (Patanè and Giampiccolo, 2004); on the other hand, earthquakes which present high frequency content and sharp arrivals, similar to those of typical earthquakes of tectonic areas, are mainly located between 5 and 20 km. Seismicity mainly occurs in the form of swarms, whereas foreshock-mainshock-aftershock sequences are rarely recorded, and seldom exceed magnitude 4.0 (Ferrucci and Patanè, 1993). The calculation of the local magnitude ML is more objective than that of MD because the measurement of the signal amplitude is less ambiguous with respect to the decay of the earthquake coda, which may be masked by the presence of noise, volcanic tremor, or other shocks (Del Pezzo and Petrosino, 2001; D'Amico and Maiolino, 2005). Therefore, since relationships adopted to estimate MD and ML for Mt. Etna region do not produce the same results, it is mandatory to adopt an empirical conversion to produce a homogeneous catalogue. Moreover, different magnitude scales strongly influence the slope of the frequency-magnitude distribution. In particular, comparing the aand bvalue of the Gutenberg-Richter, different results are obtained. The Standard Linear Regression (SLR) is the simplest and most commonly used regression procedure applied in literature to carry out MD-ML relationship (e.g. Gasperini and Ferrari, 2000; Gasperini, 2002; Bindi et al., 2005; Braunmiller et al., 2005). Its application without checking whether its basic requirements are satisfied may lead to wrong results (Castellaro et al., 2006). As an alternative it is better to use General Orthogonal Regression (GOR) relation (Carrol and Ruppert, 1996), which assume a different uncertainty for each of the two variables (Lolli and Gasperini, 2012). The application of GOR methods requires the estimate of the ratio  between the dependent and the independent variable variances, and when only the ratio variance is known, the GOR represents the simplest and mostly used approach. A database of magnitude observations recorded at Mt. Etna during the period 2005 – 2012 is adopted for this study. The new ML-MD relationship obtained by applying the GOR is:
Descriptive Analysis of the Regional Innovation System - Novel Method for Public Administration Authorities

Making innovation is currently one of the key factors of economic development, both for the private sector and the public sector. The public sector can help to support the effective form of knowledge creation and development that will lead to real innovations in the administrated region. Innovations can help meet the objectives of public policies (such as the creation of new jobs and support small and medium-sized enterprises, etc.). This paper tries to summarize the findings regarding knowledge and the innovation environment that public authorities can support in the form of regional innovation systems (RIS). Authors suggest a novel method for increasing efficiency of public financial support. This method was proven in RIS research in the Czech Republic, where the strategic documents initiating support RIS were created. The authors discuss the characters which adequately describe RIS. The added value of this paper is represented by the methodology of RIS describing and listing the public authorities’ roles in establishing a knowledge environment.
'Captive Markets': The Impact of Kidnappings on Corporate Investment in Colombia

Este estudio explota la variacion de los secuestros ocurridos en Colombia durante el periodo 1996-2002 para medir el impacto del crimen sobre la inversion privada. El resultado principal es que las empresas invierten menos cuando los secuestros estan dirigidos directamente contra su capital humano. Ademas, se encuentra que formas de crimen mas amplias -homicidios, ataques guerrilleros y secuestros en general- no tienen un impacto significativo sobre la inversion. Este hallazgo permite descartar la posibilidad de que el resultado principal del estudio sea producto de variables no observadas que expliquen, al mismo tiempo, la actividad criminal general y la inversion. Adicionalmente, los secuestros dirigidos contra las empresas no solo reducen la inversion de las empresas con ventas en el mercado local, sino tambien la inversion de las empresas con ventas en los mercados externos. Por esta razon, es improbable que el impacto negativo de los secuestros sobre la inversion sea resultado de una correlacion no observada entre condiciones de demanda adversas y actividad criminal. Por ultimo, los resultados son consistentes con la hipotesis de que los gerentes de las empresas se resisten a invertir cuando su libertad y su vida estan en riesgo; aunque no es del todo posible descartar explicaciones alternativas.
Classical correlation and quantum discord in critical systems

We discuss the behavior of quantum and classical pairwise correlations in critical systems, with the quantumness of the correlations measured by the quantum discord. We analytically derive these correlations for general real density matrices displaying ${Z}_{2}$ symmetry. As an illustration, we analyze both the $XXZ$ and the transverse field Ising models. Finite size as well as infinite chains are investigated and the quantum criticality is discussed. Moreover, we identify the spin functions that govern the correlations. As a further example, we also consider correlations in the Hartree-Fock ground state of the Lipkin-Meshkov-Glick model. It is then shown that both classical correlation and quantum discord exhibit signatures of the quantum phase transitions.
An Investigation of Reynolds Number Effect on the Aerodynamics of Bluff Body with Sharp Edges

In general, the aerodynamic stability of long span bridges is evaluated based on the results of wind tunnel tests in the low Reynolds number region, because in almost all wind tunnel tests, it is impracticable to satisfy Reynolds number similitude. Therefore, in order to correctly evaluate conventional wind tunnel test results, Reynolds number effects on the aerodynamic force coefficients acting on bridge decks must be carefully investigated. This paper investigate the Reynolds number effect on the aerodynamics of bridge deck section measured in the wide Reynolds number region from to based on the dimension of deck height in smooth flow. For the simulation of fluid flow, opencircuit and blowing wind tunnel was used for which the maximum nominal turbulence was 0.1%. The results show that increasing Reynolds number has less effect on the drag coefficient and Strouhal number and parameters in downstream of the model. In other words, variation of drag coefficient and Strouhal number is very small in Reynolds numbers over 20000. Increasing Reynolds number would not be followed with an outstanding change of the velocity defect while it results in reduction of half width with no effect on its growth rate.
A Novel Fusion Scheme for Vision Aided Inertial Navigation of Aerial Vehicles

Vision-aided inertial navigation is an important and practical mode of integrated navigation for aerial vehicles. In this paper, a novel fusion scheme is proposed and developed by using the information from inertial navigation system (INS) and vision matching subsystem. This scheme is different from the conventional Kalman filter (CKF); CKF treats these two information sources equally even though vision-aided navigation is linked to uncertainty and inaccuracy. Eventually, by concentrating on reliability of vision matching, the fusion scheme of integrated navigation is upgraded. Not only matching positions are used, but also their reliable extents are considered. Moreover, a fusion algorithm is designed and proved to be the optimal as it minimizes the variance in terms of mean square error estimation. Simulations are carried out to validate the effectiveness of this novel navigation fusion scheme. Results show the new fusion scheme outperforms CKF and adaptive Kalman filter (AKF) in vision/INS estimation under given scenarios and specifications.
Greening within the Johannesburg tourism and hospitality sectors

Tourism and hospitality is a booming industry with negative impacts on the environment. In order to keep up with consumer demand the industry is utilising more natural resources than previously assumed, questioning sustainability practices within the industry. However the industry can contribute to sustainable development by adopting greening principles. Unfortunately, there is limited research to establish how hotels in South African fare in the adoption of greening principles. This paper seeks to explore how important going green is to the South African government, hotel management, hotel employees and hotel shareholders. The paper reports on empirical results for and anonymous four star hotel in Johannesburg specifically within the hospitality industry and which also services the tourism industry. Empirical work by way of semi- structured interviews is reported on to explore the adopting and challengers of implementing greening principles and practices. Results indicate that adoption of greening within the hotel industry is limited with more direct support needed for hotel employees by hotel management. Communication is also needed from regional head office to hotel managers on greening initiatives. However, there is also a need for the South African government to guide hotels on implementation of greening practices.
Effect of Ba addition on the structural, dielectric and ferroelectric properties of Na0.5Bi0.5TiO3 ceramics

Abstract Lead-free (Na0.5Bi0.5)1-xBaxTiO3 (x = 0, 0.04 and 0.06) ceramics were fabricated by conventional solid phase sintering process. X-ray diffraction analysis shows that obtained specimens possess the perovskite structure. The microstructure study shows a dense structure, in good agreement with the relative density determined by the Archimedes method (above 95 %). Electric permittivity anomaly is shifted to low temperature after Ba doping of NBT. The pyroelectric and hysteresis loops measurements show that polarization and coercive field increases and decreases, respectively, after Ba doping of NBT. The obtained results are discussed in terms of ions/lattice imperfections, which create local electromechanical fields. The investigated ceramics are considered to be promising candidates for lead-free electronic materials.
Regional school choice and school selectivity: how do they relate to student performance? Evidence from PISA 2003

School choice and accountability have become popular educational policies in the US and the UK. In Europe, such policies are less often applied. Moreover, even when school choice exists, information on school quality is rarely provided, leading to pupil sorting by observable characteristics. In this paper, we estimate how the regional intensity of school choice and the regional percentage of selective schools relate to student test scores in math, reading and science at age 15. We estimate an education production function exploiting regional aggregation in 8 European countries to reduce potential endogeneity bias. We find that both the regional intensity of school choice and that of school selectivity are correlated with significantly higher student test scores.
The Uneasy Case for Product Liability

In this Article we compare the benefits of product liability to its costs and conclude that the case for product liability is weak for a wide range of products. One benefit of product liability is that it can induce firms to improve product safety. Even in the absence of product liability, however, firms are often motivated by market forces to enhance product safety because their sales may fall if their products harm consumers. Moreover, products must frequently conform to safety regulations. Consequently, product liability might not be expected to exert a significant additional influence on product safety — and empirical studies of several widely sold products fail to find an effect of product liability on the frequency of product accidents. A second benefit of product liability is that it can improve consumer purchase decisions by causing product prices to increase to reflect product risks. But because of litigation costs and other factors, product liability may raise prices excessively and undesirably chill purchases. A third benefit of product liability is that it compensates victims of product-related accidents for their losses. Yet this benefit is only partial, for accident victims are frequently compensated by insurers for some or all of their losses. Furthermore, the payment of compensation for pain and suffering actually reduces the welfare of individuals because it effectively forces them to purchase insurance for a type of loss for which they ordinarily do not wish to be covered. Offsetting the potential benefits of product liability are its costs, which are great. Notably, the transfer of a dollar to a victim of a product accident via the liability system requires more than a dollar on average in legal expenses. Given the limited benefits and the high costs of product liability, we come to the judgment that its use is often unwarranted. This is especially likely for products for which market forces and regulation are relatively strong, which includes many widely sold products. On the other hand, the use of product liability may be desirable for products for which these factors are weak. Our generally skeptical assessment of product liability for products for which market forces and regulation are strong is in tension with the broad social endorsement of such liability.
Constraints on energy release in solar flares from RHESSI and GOES X-ray observations - I. Physical parameters and scalings

Aims. We constrain energy release and particle acceleration processes in solar flares by means of comprehensively characterizing the physical parameters of both the thermal plasma and the accelerated nonthermal particles using X-ray data. Our aim is to bridge the gap between detailed case studies and large statistical studies. Methods. We obtained time series of spectral fits and images for 24 flares ranging from GOES class C3.4 to X17.2 using RHESSI hard X-ray observations. These data were used to derive basic physical parameters for the thermal plasma (using the isothermal approximation) and the injected nonthermal electrons (assuming the thick-target model). For the thermal component, this was supplemented by GOES soft X-ray data. We derived the ranges and distributions of the various parameters, the scaling with flare importance, and the relation between thermal parameters derived from RHESSI and GOES. Finally, we investigated the relation between thermal and nonthermal parameters. Results. Temperature and emission measure of the thermal plasma are strongly correlated with the peak GOES X-ray flux. Higher emission measures result both from a larger source volume and a higher density, with the latter effect being more important. RHESSI consistently gives higher temperatures and lower emission measures than GOES does, which is a signature of a multithermal plasma. The discrepancy between RHESSI and GOES is particularly pronounced in the early flare phase, when the thermal X-ray sources tend to be large and located higher in the corona. The energy input rate by nonthermal electrons is correlated with temperature and with the increase rate of emission measure and thermal energy. Conclusions. The derived relations between RHESSIand GOES-derived thermal parameters and the relation between thermal parameters and energy input by nonthermal electrons are consistent with a two-component model of the thermal flare plasma. Both RHESSI and GOES observe a cooler plasma component (≈10−25 MK) that is generated by chromospheric evaporation caused by a nonthermal electron beam. In addition, a hotter component (≥25 MK) is only detected by RHESSI; this component is more consistent with direct in situ heating of coronal plasma. With the exception of the early impulsive phase, RHESSI observes a combination of the evaporated and the directly heated component.
Audit Firm Characteristics and Auditing Quality: The Nigerian Experience

This study examines the link between auditing quality and auditor independence, auditor experience, auditor accountability. Using a sample of 210 respondents made up of finance directors, auditors, shareholders, and financial analysts and employing structural equation modeling technique for data analysis, we find that auditor independence and auditor accountability have a significant relationship with audit quality. We find that auditor experience is not a factor affecting audit quality in Nigeria. We recommend auditors should consider audit risk before embarking upon an audit so as to be independent and accountability conscious. Key words: auditing quality; audit evidence; structural equation modeling
Diffusion Weighted and Dynamic Contrast-Enhanced MRI as a Predictor of Treatment Response in Head and Neck Cancer to Chemoradiotherapy: The Role of Early Intratreatment Scanning

Background: In locoregionally advanced Head and Neck Squamous Cell Carcinoma (HNSCC), intra-treatment scanning early during the course of Concomitant Chemoradiotherapy (CRT) with advanced functional Magnetic Resonance Imaging (MRI) could potentially allow for modification of treatment to maximize the chance of favourable outcome. The aim of this prospective study was to assess the predictive value of parameters derived from Dynamic Contrast-Enhanced (DCE) and Diffusion Weighted (DW) MRI for treatment response early during the course of CRT in patients with HNSCC.Methods: MRI scans were performed in 20 patients with locoregionally advanced HNSCC at baseline, after 10 Grays (Gy) and 40 Gy of CRT. DW and DCE derived parameters as well as the volumes were measured from primary tumours and lymph nodes. Tumour kinetic parameters (volume transfer constant (Ktrans), extracellular extravascular volume fraction (ve) and plasma volume fraction (Vp)) were assessed using the extended Tofts model. Relative changes in studied parameters from baseline to 10 Gy and 40 Gy were calculated. Factors predictive for treatment response were identified by the Firth logistic regression. Spearman’s rank correlation coefficient was used to investigate correlations among the parameters.Results: Responders showed a significant decrease in Ktrans after 10 Gy (median, -50.2 %; range, -25.1 to -90.9 %; P = 0.047). In addition, decreased ve after 10 Gy (median, -26.9%; range -76.7 to -126.8%) and increased apparent diffusion coefficient (ADC) after 40 Gy (median, 73.4%; range, 17.8 - 121.6%) were borderline significant (P=0.066 and P=0.079, respectively). Positive correlation between Ktrans and ve after 10 Gy (r = 0.823, P <0.05) was noticed.Conclusion: In HNSCC, early changes in DCE- and DWI-MRI derived parameters appear to predict tumour response before the actual morphologic changes occur.
ALTERNATIVE MONETARY SYSTEMS AND THE QUEST FOR STABILITY: CAN A FREE BANKING SYSTEM DELIVER IN SOUTH AFRICA?

Since the early 1900s central banking has developed into the most widely adopted monetary regime by sovereign states. Yet, there is a broad raft of evidence which shows that central banking systems have been less successful in delivering macroeconomic stability than alternative monetary systems. The argument is pronounced in the case of emerging economies, a set of countries which includes South Africa. Against this backdrop, this paper reviews the case for central banking in South Africa. Our results lead us to explore various alternatives to central banking, including Dollarisation and monetary union. However, because these systems are not without their own vulnerabilities, we consider a third alternative regime, free banking. We argue that, despite being an almost completely forgotten system, free banking has the capacity to improve South Africa's monetary system and enhance the country's macroeconomic stability. Copyright 2005 Economic Society of South Africa.