Miracle-dz/UniFAR-FTUs huggingface dataset:
Differentiated bertrand duopoly with variable demand

Abstract Two one-product firms compete in prices on a market with differentiated products. Goods are differentiated because customers switch from one good to the other at different relative prices. With the specification that mean demand in the market is unit-elastic, I provide conditions on the shape of the customer density which guarantee the existence of a unique Bertrand equilibrium.
Entrepreneurship in Emerging Economies: Where Are We Today and Where Should the Research Go in the Future

Emerging economies are characterized by an increasing market orientation and an expanding economic foundation. The success of many of these economies is such that they are rapidly becoming major economic forces in the world. Entrepreneurship plays a key role in this economic development. Yet to date, little is known about entrepreneurship in emerging economies. This introductory article to the special issue on entrepreneurship in emerging economies examines the literature that exists to date in this important domain. It then reviews the research that was generated as part of this special issue on this topic. The article concludes with a discussion of the critical future research needs in this area.
Private Equity versus Stocks

In this article the risk and return characteristics and diversification benefits when private equity is used as a portfolio component are investigated. The analysis is based on actual cash flows to and from portfolio companies. Using a dataset that provides complete information for 3620 investments made by 123 funds from 37 investment managers the authors find a dramatic increase in the extent to which private equity outperforms stock investment during the late 1990s. Within the overall class of private equity, returns on earlier private equity investment categories, including venture capital, show on average higher variations and even higher rates of failure. However, by selecting a few extremely well-performing companies, one can achieve high average returns, thus compensating for lost investments. An analysis of various private equity subcategories shows that there is a wide range of optimal allocations to this asset class that minimizes mixed-asset portfolio variance or maximizes performance ratios.
Intraindustry Trade: Sources and Effects on Protection

This paper provides an empirical analysis of the determinants of intraindustry trade. We demonstrate that two-way trade flows occur where conditions are favorable to international specialization consistent with the Stigler-Williamson analysis of the division of labor. The results are inconsistent with the prevailing product differentiationcum-scale economies model of intraindustry trade. In addition, we show that intraindustry trade has a significant impact on protectionist pressures. Exports of closely related products have the effect of mitigating the tariff-raising effects that imports would otherwise exert.
Time Series Analysis of Export Demand Equations: A Cross-Country Analysis

The paper estimates export demand elasticities for a large number of developing and industrial countries, using time-series techniques that account for the nonstationarity in the data. The average long-run price and income elasticities are found to be approximately -1 and 1.5, respectively. Thus, exports do react to both the trade partners' income and to relative prices. Africa faces the lowest income elasticities for its exports, while Asia has both the highest income and price elasticities. The price and income elasticity estimates have good statistical properties.
Estimating DSGE model parameters in a small open economy: Do real-time data matter?

Abstract This paper investigates the differences between parameters estimated using real-time and those estimated with revised data. The models used are New Keynesian DSGE models of the Czech, Polish, Hungarian, Swiss, and Swedish small open economies in interaction with the euro area. The paper also offers an analysis of data revisions of GDP growth and inflation and trend revisions of interest rates. Data revisions are found to be unbiased and not autocorrelated in all countries. Inflation is usually measured more accurately in real-time than GDP growth, but this is not the case in the euro area. The results of the core analysis suggest that there are significant differences between parameter estimates using real-time data and those estimated using revised data. The model parameters that are most prone to significant differences between real-time and revised estimations are habit in consumption and persistence of domestic supply, of demand, and of world-wide technology shocks. The impulse response analysis suggests that the model behavior based on real-time and revised data is different.
Empirical Study on the Impact of User Participation on Service Value

As enterprise systems (ES) becomes increasingly pervasive and commoditized in organizations, its service value emerges as a critical issue. Drawing on the customer value theory, this paper studies the relationship between user participation and service value of enterprise systems in the stage of enterprise system improvement. A survey of 220 employees in a large-scale industrial enterprise was taken to investigate the relationship between them. User participation has direct positive impacts on service value in the process of system improvement. Furthermore, information service quality and non-monetary sacrifice serve as mediating variables of the relationship between user participation in system improvement and service value even after controlling for individual variables such as users’ age, education, and IT-related education. This paper contributes to the theory on whether user participation matters in the process of enterprise system improvement. The findings can also encourage managerial practitioners to exploit user participation in organizations, in order to enhance service value of enterprise system.
Multiview Reconstruction of Complex Organic Shapes

We propose a novel narrow baseline multiview stereo surface reconstruction method that is specifically aimed at complex shapes of biological origin that show many thin protrusions and curved occluding contours. Our method is built around fitting local quadrics to occluding contours and it thus avoids any planarity assumptions that are common to other state of the art methods. We describe a complete pipeline that begins with calibrated noisy images and produces a final watertight surface. We present a novel technique to detect pixel precise internal contours and to fit local quadrics to them. This procedure is designed to deal with curved occluding contours, and it is very robust to noise and to slow changes in surface radiance. Our method can even reconstruct shapes from sequences where the illumination is attached to the observer and not the scene. We demonstrate the potential of our method by reconstructing the intricate shape of a tiny insect from images taken under a scanning electron microscope.
Psychomotor Development in Children with Iron Deficiency and Iron-Deficiency Anemia

Background Iron deficiency and iron-deficiency anemia are the most common nutritional deficiencies in children, especially in developing countries. Iron-deficiency anemia in infancy is associated with impaired neurodevelopment. Studies have shown an association between iron deficiency without anemia and adverse effects on psychomotor development. Objective To determine the effects of iron deficiency and iron-deficiency anemia on psychomotor development in childhood. Methods We evaluated psychomotor development in healthy children with iron deficiency and iron-deficiency anemia with the use of the Denver II Developmental Screening Test (DDST-II). If the child score was more than 90th percentile compared to children in the same age group, the test was scored as “delay”; it was scored as a “caution” if the child score was between the 75th and 90th percentiles. The test result was interpreted as “normal,” if there was no delay and only one “caution” for any item. If the child had one or more “delays” or more than two “cautions,” the result was classified as “abnormal. ” Results DDST-II scores were abnormal in 67.3% of subjects with iron-deficiency anemia, 21.6% of those with iron deficiency, and 15.0% of control subjects. The difference from the control group in the percentage of abnormal scores was significant for subjects with iron-deficiency anemia (p < .01) but not for those with iron deficiency (p = 0.203); p > . 05. (p-value, post-hoc comparison of 2 groups.) Conclusions Iron-deficiency anemia impaired psychomotor development during childhood. However, the evidence on the adverse effects of iron deficiency remains controversial. The Denver II Developmental Screening Test is a valuable test to detect early developmental delays, especially in infants with risk factors.
The Keck Interferometer

The Keck Interferometer (KI) combined the two 10 m W. M. Keck Observatory telescopes on Mauna Kea, Hawaii, as a long-baseline near- and mid-infrared interferometer. Funded by NASA, it operated from 2001 until 2012. KI used adaptive optics on the two Keck telescopes to correct the individual wavefronts, as well as active fringe tracking in all modes for path-length control, including the implementation of cophasing to provide long coherent integration times. KI implemented high sensitivity fringe-visibility measurements at H (1.6 μm), K (2.2 μm), and L (3.8 μm) bands, and nulling measurements at N band (10 μm), which were used to address a broad range of science topics. Supporting these capabilities was an extensive interferometer infrastructure and unique instrumentation, including some additional functionality added as part of the NSF-funded ASTRA program. This paper provides an overview of the instrument architecture and some of the key design and implementation decisions, as well as a description of all of the key elements and their configuration at the end of the project. The objective is to provide a view of KI as an integrated system, and to provide adequate technical detail to assess the implementation. Included is a discussion of the operational aspects of the system, as well as of the achieved system performance. Finally, details on V2 calibration in the presence of detector nonlinearities as applied in the data pipeline are provided.
Verbal Memory and Brain Aging

Objective: Analysis sought to determine whether Wechsler Memory Scale-Logical Memory (LM)-correct responses and errors were related to magnetic resonance imaging (MRI) brain volume measurements. Methods: The LM immediate (LM-I) and LM delay (LM-D) free recall correct responses and related and unrelated errors were scored. Principal components analysis yielded a 3-factor solution: LM-I and LM-D correct responses, LM-I and LM-D-unrelated errors, and LM-I/-D-related errors. The MRI total cerebral brain volume, frontal brain volume, temporal horn volume (THV), and white matter hyperintensities volume (WMHIV) were obtained. Results: Increasing THV (suggesting greater regional atrophy) was associated with lower scores on the LM-correct responses factor. Extensive WMHIV was associated with higher scores on the LM-related errors factor. Conclusion: These results suggest that LM-correct responses could relate to emerging brain alterations. Longitudinal research might enhance the sensitivity of this test to identify preclinical impairment and persons at risk of mild cognitive impairment and dementia.
Neuromuscular Adaptations to Multimodal Injury Prevention Programs in Youth Sports: A Systematic Review with Meta-Analysis of Randomized Controlled Trials

Objective: Neuromuscular injury prevention programs (IPP) can reduce injury rate by about 40% in youth sport. Multimodal IPP include, for instance, balance, strength, power, and agility exercises. Our systematic review and meta-analysis aimed to evaluate the effects of multimodal IPP on neuromuscular performance in youth sports. Methods: We conducted a systematic literature search including selected search terms related to youth sports, injury prevention, and neuromuscular performance. Inclusion criteria were: (i) the study was a (cluster-)randomized controlled trial (RCT), and (ii) investigated healthy participants, up to 20 years of age and involved in organized sport, (iii) an intervention arm performing a multimodal IPP was compared to a control arm following a common training regime, and (iv) neuromuscular performance parameters (e.g., balance, power, strength, sprint) were assessed. Furthermore, we evaluated IPP effects on sport-specific skills. Results: Fourteen RCTs (comprising 704 participants) were analyzed. Eight studies included only males, and five only females. Seventy-one percent of all studies investigated soccer players with basketball, field hockey, futsal, Gaelic football, and hurling being the remaining sports. The average age of the participants ranged from 10 years up to 19 years and the level of play from recreational to professional. Intervention durations ranged from 4 weeks to 4.5 months with a total of 12 to 57 training sessions. We observed a small overall effect in favor of IPP for balance/stability (Hedges' g = 0.37; 95%CI 0.17, 0.58), leg power (g = 0.22; 95%CI 0.07, 0.38), and isokinetic hamstring and quadriceps strength as well as hamstrings-to-quadriceps ratio (g = 0.38; 95%CI 0.21, 0.55). We found a large overall effect for sprint abilities (g = 0.80; 95%CI 0.50, 1.09) and sport-specific skills (g = 0.83; 95%CI 0.34, 1.32). Subgroup analyses revealed larger effects in high-level (g = 0.34–1.18) compared to low-level athletes (g = 0.22–0.75), in boys (g = 0.27–1.02) compared to girls (g = 0.09–0.38), in older (g = 0.32–1.16) compared to younger athletes (g = 0.18–0.51), and in studies with high (g = 0.35–1.16) compared to low (g = 0.12–0.38) overall number of training sessions. Conclusion: Multimodal IPP beneficially affect neuromuscular performance. These improvements may substantiate the preventative efficacy of IPP and may support the wide-spread implementation and dissemination of IPP. The study has been a priori registered in PROSPERO (CRD42016053407).
Correlation Between Rotor Vibration and Mechanical Stress in Ultra-High-Speed Permanent Magnet Synchronous Motors

This paper investigates the correlation between rotor vibration and mechanical stress in ultra-high-speed permanent magnet synchronous motors (PMSMs); the mechanical stress generated in the PM and the rotational vibration when the PMSM rotates at high speeds were evaluated. Two PM rotors that have the same performance characteristics but different shrink fits were studied, and the vibration of these two PM rotors was analyzed. Furthermore, to evaluate the correlation between mechanical stress and vibration, the rotor design parameters, such as sleeve thickness and shrink fit, were varied. Based on the analysis results, a real-world model was developed and an experiment was conducted to test the vibration of these two rotors; the validity of our results was verified by performing experiments.
Socioeconomic status of parents and the occurrence of pelvic inflammatory disease among undergraduates attending Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria

Background: Pelvic inflammatory disease (PID) is a major cause of gynaecological morbidity globally. Complications from PID include infertility, ectopic pregnancy and chronic pelvic pain. Low socioeconomic status (SES) is a risk factor for the occurrence of PID. Objective: The aim of this study was to determine the association between SES of parents and the occurrence of PID among undergraduates attending Irrua Specialist Teaching Hospital, Irrua. Methodology: The study was a hospital-based, descriptive cross-sectional study. Three hundred and sixty female undergraduates attending the hospital were consecutively recruited and clinically assessed for the presence of PID using the WHO and CDC MMWR 2010 criteria for the clinical assessment of PID. Their SES was determined by Oyedeji social class categorisation. Data were analysed using Epi Info 3.5. 4. Descriptive statistics were used to summarise the data, and Chi-square was used to test for association. Results: There was a significant association between SES of parents and multiple sex partners (P < 0.02), previous sexually transmitted infection (STI) (P = 0.05), unprotected sex (P < 0.001), history of induced abortion (P < 0.001) and surgical termination of pregnancy (P < 0.01). There was also association between occurrence of PID among respondents and multiple sexual partners (P < 0.001), previous history of STI (P = 0.02), non-persistent use of condom (P < 0.001), history of induced abortion (P < 0.01) and surgical termination of pregnancy (P < 0.01). There was however no significant association between SES of parents and occurrence of PID (P = 0.14) though PID was highest among respondents from low SES. Conclusion: Occurrence of PID among undergraduates was not associated with their SES. However, identified risk factors for PID among study population such as multiple sex partners, previous STI, unprotected sex and history of induced abortion were associated with the SES.
Performance of Islamic and mainstream banks in Malaysia

The study found that Islamic banking scheme (IBS) banks have recorded higher return on assets (ROA) as they are able to utilize existing overheads carried by mainstream banks. As this lowers their overhead expenses, it is found that the higher ROA ratio for IBS banks does not imply efficiency. It is also inconsistent with their relatively low asset utilization and investment margin ratios. This finding confirmed our contention that Islamic banking that thrives on interest‐like products (credit finance) is less likely to outshine mainstream banks on efficiency terms. Although Islamic credit finance products may have complied with Shariah rules, their lack of ethical content is not expected to motivate IBS banks to strive for efficiency through scale and scope economies.
Non-blocking Writes to Files

Writing data to a page not present in the file-system page cache causes the operating system to synchronously fetch the page into memory first. Synchronous page fetch defines both policy (when) and mechanism (how), and always blocks the writing process. Non-blocking writes eliminate such blocking by buffering the written data elsewhere in memory and unblocking the writing process immediately. Subsequent reads to the updated page locations are also made non-blocking. This new handling of writes to non-cached pages allow processes to overlap more computation with I/O and improves page fetch I/O throughput by increasing fetch parallelism. Our empirical evaluation demonstrates the potential of nonblocking writes in improving the overall performance of systems with no loss of performance when workloads cannot benefit from it. Across the Filebench write workloads, non-blocking writes improve benchmark throughput by 7X on average (up to 45.4X) when using disk drives and by 2.1X on average (up to 4.2X) when using SSDs. For the SPECsfs2008 benchmark, nonblocking writes decrease overall average latency of NFS operations between 3.5% and 70% and average write latency between 65% and 79%. When replaying the MobiBench file system traces, non-blocking writes decrease average operation latency by 20-60%.
Mutational analysis of the cysteine residues in the hepatitis B virus small envelope protein

The small envelope protein of hepatitis B virus is the major component of the viral coat and is also secreted from cells as a 20-nm subviral particle, even in the absence of other viral proteins. Such empty envelope particles are composed of approximately 100 copies of this polypeptide and host-derived lipids and are stabilized by extensive intermolecular disulfide cross-linking. To study the contribution of disulfide bonds to assembly and secretion of the viral envelope, single and multiple mutants involving all 14 cysteines in HepG2 and COS-7 cells were analyzed. Of the six cysteines located outside the region carrying the surface antigen, Cys-48, Cys-65, and Cys-69 were each found to be essential for secretion of 20-nm particles, whereas Cys-76, Cys-90, and Cys-221 were dispensable. By introduction of an additional cysteine substituting serine 58, the yield of secreted particles was increased. Of four mutants involving the eight cysteines located in the antigenic region, only the double mutant lacking Cys-121 and Cys-124 was secreted with wild-type efficiency. Secretion-competent envelope proteins were intracellularly retained by secretion-deficient cysteine mutants. According to alkylation studies, both intracellular and secreted envelope proteins contained free sulfhydryl groups. Disulfide-linked oligomers were studied by gel electrophoresis under nonreducing conditions.
A Characterization of Adult Victims of Sexual Violence: Results From the National Epidemiological Survey for Alcohol and Related Conditions

Sexual violence can cause acute and persistent negative psychological outcomes among children and adults in a community. Previous studies have frequently reported high prevalence of prior child and adolescent sexual abuse among adult victims of sexual violence. This raises uncertainty over the specific contribution of sexual victimization in adulthood to the adverse psychological outcomes. The present study draws on a large nationally representative sample of adults without history of childhood sexual abuse, and applies diagnostic criteria of DSM-IV, in order to investigate the risk factors and psychiatric comorbidities correlated with sexual victimization in adulthood. In a large representative sample of U.S. adults without history of childhood sexual abuse, 2.5% reported sexual victimization in adulthood. Female gender, living alone, economic disadvantage, and a history of childhood adversities and parental psychopathology were identified as risk factors. Adult sexual victimization increased the risk of developing a variety of psychiatric disorders, especially PTSD (HR = 3.43, 95% CI [2.67, 4.41]) and drug abuse (HR = 3.38, 95% CI [2.49, 4.58]). Conversely, pre-existing psychiatric psychopathology, particularly PTSD (HR = 3.99, 95% CI [2.68, 5.94]) and dysthymia (HR = 2.26, 95% CI [1.42, 3.59]), increased the likelihood of sexual victimization in adulthood. Childhood experience and adulthood sociodemographic characteristics are important in affecting the risk of being sexually victimized in adulthood. Psychiatric disorders can act as both risk factors and outcomes of adult sexual victimization.
Structural Change in the Mortgage Market and the Propensity to Refinance

We hypothesize that the intrinsic benefit required to trigger a refinancing has become smaller due to a combination of technological, regulatory, and structural changes that have made mortgage origination more competitive and more efficient. To test this hypothesis, we estimate an empirical hazard model of loan survival for two subperiods, using a database that allows us to carefully control for homeowners' credit ratings, equity, loan size, and measurable transaction costs. Our findings strongly confirm that credit ratings and home equity have significant effects on the refinancing probability. In addition, we provide evidence that homeowners postpone refinancing in the face of increased interest rate volatility, consistent with option value theory. Finally, our results clearly support the hypothesis that structural change in the mortgage market has increased homeowners' propensity to refinance.
MDRD Equations for Estimation of GFR in Renal Transplant Recipients

After renal transplantation monitoring and detection of slight‐to‐moderate changes in GFR is a prerequisite for an optimal patient management. Recently, several equations to estimate GFR were developed and verified in the MDRD study cohort. However, little is known about the application of the MDRD formulas in the setting of renal transplantation.