Miracle-dz/UniFAR-FTUs huggingface dataset:
Oral and injectable contraception use and risk of HIV acquisition among women in sub-Saharan Africa

Objective:To evaluate the effect of oral and injectable hormonal contraception on the risk of HIV acquisition among women in South Africa and Zimbabwe. Design:Secondary data analysis of 4913 sexually active women aged 18–49 years followed for up to 24 months in the Methods for Improving Reproductive Health in Africa (MIRA) phase III effectiveness trial of the diaphragm and lubricant gel for HIV prevention. Methods:Participants were interviewed quarterly about contraception and sexual behavior and were tested for pregnancy, HIV, and other sexually transmitted infections. We used a Cox proportional hazards marginal structural model, weighted by the inverse probability of hormonal contraception use, to compare the risk of HIV acquisition among nonpregnant women reporting use of combined oral contraceptive pills (COC), progestin-only pills (POP), and/or injectable hormonal contraception to women not using these methods. Results:During the study, 283 participants seroconverted. Use of oral contraceptives (POP or COC) was not associated with HIV risk [adjusted hazard ratio (HRa) = 0.86, 95% confidence interval (CI) 0.32, 1.78]. Injectable hormonal contraception was associated with a small nonsignificant risk of HIV infection (HRa = 1.34, 95% CI 0.75, 2.37). The effect of injectable hormonal contraception was similar in the unweighted site-adjusted only (HRa = 1.32, 95% CI 1.00, 1.74) and baseline factor adjusted models (HRa = 1.27, 95% CI 0.94, 1.72). Conclusions:In this study, oral contraceptives were not associated with HIV acquisition. There is substantial uncertainty in the effect of injectable hormonal contraception on HIV risk. These findings underscore the importance of dual protection with condoms and the need for diverse contraceptive options for women at risk of HIV infection.
Performance of chemical shift-based water-fat separation with self-calibrated fat spectrum is sensitive to echo times

Chemical shift-based water-fat separation method utilises water-fat resonance frequency difference to decompose signals into water and fat partitions in magnetic resonance imaging (MRI) on a pixel-wise basis. It provides an effective way to measure fat fraction, or to suppress fat signal which might obscure underlying pathology. IDEAL (Iterative decomposition of water and fat with echo asymmetry and least-squares estimation) algorithm with multi-peak fat spectral modelling has been developed. Recent studies have discussed the performance of this algorithm assuming that the frequencies and relative amplitudes of fat peaks are constant among all subjects. However, the fat spectra vary in different tissues, thus a self-calibration method which estimates the fat spectrum directly from the data provides more accurate results. In this work, we analyse the performance of multi-peak IDEAL algorithm with self-calibrated fat spectrum by theoretical calculation, simulation, and experiments, and find optimal echo time increments which provide reliable water-fat separation.
Microfoundations, Method, and Causation: On the Philosophy of the Social Sciences

The convergence of inexactness and intelligibility in social phenomena makes social and historical inquiry fascinating. The social world is not chaotic and social processes are not unrelated strings of events. We can explain social patterns in ways that illuminate social outcomes. At the same time, the social world does not constitute a closed, determined system of variables and outcomes, in the same way that quantum chemistry systemizes the properties of all physical structures. Instead, the social sciences are a tangle of cross-cutting, overlapping sets of theories, hypotheses, causal models, idealized facts, interpretive principles, and bodies of empirical findings that may illuminate but do not reduce. In Microfoundations, Method, and Causation, Daniel Little combines a purely philosophical perspective on social science, with the theoretical and empirical practice of working scientists. Part 1 focuses on the theory of popular politics constructed within the context of analytical Marxism. In part 2, Little asks if rational choice theory provides an adequate basis for explaining patterns of social, political, and economic behavior in traditional China. The essays in part 3 reveal the philosophy of social science as understood by philosophers. Here, Little probes issues of objectivity, empiricism, and generalizations, and makes the case that social generalizations are not akin to laws of nature. Little's approach to social science research effectively points out the limits inherent in social theories, as well as questions and answers that may be posed to the social world. In a clear, compelling, and honest fashion, he urges both the social scientist and the philosopher who studies the social sciences, to make the most of empirical methods of research to develop hypotheses about the social world. As such, this is a must read for sociologists, social theorists, and philosophers.
High speed video monitoring system for eyelid movement measurements

The paper presents a high speed video processing algorithm designed to measure several parameters related to eyelid movements during blinking. First, the facial features of the subject are detected and tracked; then, the eye regions of interest are extracted using data regarding face orientation and eyebrows position. In the next stage, eye contour and representative lines for upper and lower eyelids are detected in each video sequence frame. Finally eyelid characteristics are extracted from the eyelid measurements data.
The Influence of Teachers' Nonverbal Behaviors on Students' Perceptions and Performance

The Elementary School Journal Volume 85, Number 4 ? 1985 by The University of Chicago. All rights reserved. 0013-5984/85/8504-0005$01.00 PROFESSOR: How do you know when your teacher really means what she says? THIRD Well, her eyes get big and GRADER: round and she looks right at us. She doesn't move and her voice is a little louder, but she talks kinda slowly. Sometimes she stands over us and looks down at us. PROFESSOR: What happens then? THIRD The class does what she GRADER: wants! [Woolfolk 1983]
Triphenylmethylphosphonium (TPMP+) as a Probe for Peritubular Membrane Potential in the Kidney Slice

Abstract The present work was undertaken to assess the validity of the use of TPMP+, a lipophilic cation, as a basolateral membrane-potential probe in the rabbit kidney slice. Cortical slices incubated in media containing 3H-TPMP+ reached an equilibrium slice/medium concentration ratio (S/M) for TPMP+ after 90 min. The equilibrium S/M TPMP+ was ∼20 at TPMP+ concentrations between 30 and 50 μM. Concentrations of TPMP+ above 50 μM resulted in changes in tissue electrolytes and O2 consumption. Anaerobic incubation of slices in the presence of iodoacetamide decreased the S/M TPMP to ∼3. When medium K+ was progressively increased, the S/M TPMP+ decreased continuously. There was a linear correlation between cell water/medium concentration ratios (C/M) for TPMP+ and K+ (r = 0.629, P < 0.01). However, the C/M TPMP+ was 29.0 even at C/M K+ of 1.0, strongly suggesting the presence of a tissue binding component for TPMP+. When corrections are made for the above binding, the average C/M TPMP+ in slices incubated in the normal medium was ∼13, equivalent to a Nernst potential of −64 mV. This value compared favorably to −54.3 mV obtained by microelectrodes in slices treated in the same fashion. It is concluded that the C/M TPMP+ corrected for binding may be used as a measure of the basolateral membrane potential in the steady state.
Correlation of regional cerebral blood flow and change of plasma sodium concentration during genesis and satiation of thirst.

Positron emission tomography studies were conducted during genesis of moderate thirst by rapid i.v. infusion of hypertonic saline (0.51 M) and after satiation of thirst by drinking water. The correlation of regional cerebral blood flow with the change in the plasma Na concentration showed a significant group of cerebral activations in the anterior cingulate region and also a site in the middle temporal gyrus and in the periaqueductal gray. Strongest deactivations occurred in the parahippocampal and frontal gyri. The data are consistent with an important role of the anterior cingulate in the genesis of thirst.
A Conceptual Study of Model Selection in Classification - Multiple Local Models vs One Global Model

A key concept in model selection is to understand how model complexity can be modified to improve in generalization performance. One design alternative is to increase model complexity on a single global model (by increasing the degree of a polynomial function); another alternative is to combine multiple local models into a composite model. We provide a conceptual study that compares these two alternatives. Following the Structural Risk Minimization framework, we derive bounds for the maximum number of local models or folds below which the composite model remains at an advantage with respect to the single global model. Our results can be instrumental in the design of learning algorithms displaying better control over model complexity.
Clinical outcome and microvascular blood flow in VAC®‐ and Sorbalgon®‐treated peri‐vascular infected wounds in the groin after vascular surgery – an early interim analysis

Vacuum‐assisted wound closure (VAC®) therapy is considered to be superior to conventional dressings in the treatment of peri‐vascular groin infections after vascular surgery at our department. Therefore, we performed an early interim analysis of the clinical outcomes in these seriously ill patients at risk of amputation and death. Patients were randomised to either VAC® (n = 5) or Sorbalgon® (n = 5; best alternative treatment) therapy after surgical debridement. Non‐invasive, laser Doppler perfusion imaging (LDPI) studies of the skin adjacent to the undressed wound were performed after 14 days of wound treatment. There was no difference in LDPI values in VAC® versus Sorbalgon® treated patients (P = 0·46). One patient in the VAC® group suffered from two re‐bleeding episodes, leading to vascular resection and transfemoral amputation and in the Sorbalgon® group two had a complete wound healing time of more than 4 months and one had a visible interposition bypass graft in the groin after 1 month of treatment. No patient died of the groin infection. Although not statistically proven, fewer wound treatment failures were recorded in the VAC® group, justifying this early interim analysis. LDPI studies were feasible.
Acceleration of the FEM computations in electromagnetic analysis for switched reluctance motor

In this paper an application of parallel computing to accelerate modeling of subsystem in the frame of HiL (Hardware-in-the-Loop) platform is presented. The subsystem is the model of SRM (Switched Reluctance Motor), analyzed with the use of numerical method FEM (Finite Element Method). The paper focuses on potential of the GPU (Graphical Processing Unit) Tesla cards, which are made in a Fermi and Kepler technology to optimize computation time. The FEM is analyzed and possible accelerations of this method are emphasized. A bottleneck of the FEM is a necessity to solve LSE (Linear System of Equations), with very large and sparse matrices, which are results of PDEs (Partial Differential Equations) discretization process. This paper examines parallelism of the sparse matrices solvers on the high-end GPUs. Variations of the iterative CG (Conjugate Gradient) solver were analyzed, due to the CG is the iterative solver used in FEMM, freeware software package for 2D FEA (Finite Element Analysis) of EM (Electro-Mechanical) systems. The Conjugate-Gradient without preconditioner, CG with Jacobi preconditioner, CG with ilu0 preconditioner were analyzed. In parallel computations CULA tools routines for iterative solvers were used.
Efficient pixel-accurate rendering of curved surfaces

A curved or higher-order surface, such as spline patch or a Bézier patch, is rendered pixel-accurate if it displays neither polyhedral artifacts nor parametric distortion. This paper shows how to set the evaluation density for a patch just finely enough so that parametric surfaces render pixel-accurate in the standard graphics pipeline. The approach uses tight estimates, not of the size under screen-projection, but of the variance under screen projection between the exact surface and its triangulation. An implementation, using the GPU tessellation engine, runs at interactive rates comparable to standard rendering.
Corticosteroid-Induced Neural Remodeling Predicts Behavioral Vulnerability and Resilience

Neurons in distinct brain regions remodel in response to postnatal stressor exposure, and structural plasticity may underlie stress-related modifications in behavioral outcomes. Given the persistence of stress-related diseases such as depression, a critical next step in identifying the contributions of neural structure to psychopathology will be to identify brain circuits and cell types that fail to recover from stressor exposure. We enumerated dendritic spines during and after chronic stress hormone exposure in hippocampal CA1, deep-layer prefrontal cortex, and the basal amygdala and also reconstructed dendritic arbors of CA1 pyramidal neurons. Corticosterone modified dendritic spine density in these regions, but with the exception of the orbitofrontal cortex, densities normalized with a recovery period. Dendritic retraction of hippocampal CA1 neurons and anhedonic-like insensitivity to a sucrose solution also persisted despite a recovery period. Using mice with reduced gene dosage of p190rhogap, a cytoskeletal regulatory protein localized to dendritic spines, we next isolated structural correlates of both behavioral vulnerability (spine elimination) and resilience (spine proliferation) to corticosterone within the orbital cortex. Our findings provide novel empirical support for the perspective that stress-related structural reorganization of certain neuron populations can persist despite a “recovery” period from stressor exposure and that these modifications may lay a structural foundation for stressor vulnerability—or resiliency—across the lifespan.
Knockdown of Human Nα-Terminal Acetyltransferase Complex C Leads to p53-Dependent Apoptosis and Aberrant Human Arl8b Localization

ABSTRACT Protein Nα-terminal acetylation is one of the most common protein modifications in eukaryotic cells. In yeast, three major complexes, NatA, NatB, and NatC, catalyze nearly all N-terminal acetylation, acetylating specific subsets of protein N termini. In human cells, only the NatA and NatB complexes have been described. We here identify and characterize the human NatC (hNatC) complex, containing the catalytic subunit hMak3 and the auxiliary subunits hMak10 and hMak31. This complex associates with ribosomes, and hMak3 acetylates Met-Leu protein N termini in vitro, suggesting a model in which the human NatC complex functions in cotranslational N-terminal acetylation. Small interfering RNA-mediated knockdown of NatC subunits results in p53-dependent cell death and reduced growth of human cell lines. As a consequence of hMAK3 knockdown, p53 is stabilized and phosphorylated and there is a significant transcriptional activation of proapoptotic genes downstream of p53. Knockdown of hMAK3 alters the subcellular localization of the Arf-like GTPase hArl8b, supporting that hArl8b is a hMak3 substrate in vivo. Taken together, hNatC-mediated N-terminal acetylation is important for maintenance of protein function and cell viability in human cells.
Fan beam formation using spiral array antennas

Two types of spiral array antennas that form circularly polarized fan beams are numerically analyzed. One is composed of two-arm elliptical spiral elements, and the other is composed of single-arm round spiral elements. It is found that the elliptical spiral array antenna can radiate a wider fan beam than a conventional round spiral array antenna. It is also found that the single-arm spiral array antenna can radiate a fan beam off-normal to the antenna plane.
State estimation of spacecraft formation near small asteroid

An autonomous navigation method is investigated to estimate the states of each spacecraft relative to the asteroid. Inter-spacecraft position measurements are then combined with the spacecraft-to-asteroid position measurements to improve the navigation accuracy. Two navigation schemes based on different combinations of measurements are constructed to evaluate the improvement in navigation performance. Unscented Kalman Filter is used to estimate the state for each spacecraft with respect to the asteroid. Results show that the navigation performance is significantly improved by adding the inter-spacecraft position measurements.
Financial Incentives in Academia: Research versus Development

This paper investigates the effects of monetary rewards on the pattern of research. We build a simple repeated model of a researcher capable to obtain innovative ideas. We analyse how the legal environment affects the allocation of researcher's time between research and development. Although technology transfer objectives reduce the time spent in research, they might also induce researchers to conduct research that is more basic in nature, contrary to what the "skewing problem" would presage. We also show that our results hold even if development delays publication.
The Effects of Harmonic Accompaniment on the Tonal Improvisations of Students in First Through Sixth Grade

The purpose of this research was to examine the effects of harmonic accompaniment on the tonal improvisations of elementary school students. Specifically, this study was designed to (a) determine if the addition of a root melody accompaniment to song instruction affects the implied harmonic changes and harmonic rhythm in the tonal improvisations of students in first through sixth grade and (b) determine whether age affects the tonal improvisation scores of students in first through sixth grade. Results indicated that students who received song instruction with root melody accompaniment received significantly higher tonal improvisation rating scores than those students who did not have such instruction. No statistical difference was found for the main effect of grade level.
The High School Environment and the Gender Gap in Science and Engineering

Despite the striking reversal of the gender gap in education, women pursue science, technology, engineering, and mathematics (STEM) degrees at much lower rates than those of their male peers. This study extends existing explanations for these gender differences and examines the role of the high school context for plans to major in STEM fields. Building on recent gender theories, we argue that widely shared and hegemonic gender beliefs manifest differently across schools so that the gender-specific formation of study plans is shaped by the local environment of high schools. Using the National Education Longitudinal Study, we first show large variations between high schools in the ability to attract students to STEM fields conditional on a large set of pre–high school measures. Schools that are successful in attracting students to these fields reduce the gender gap by 25 percent or more. As a first step toward understanding what matters about schools, we then estimate the effect of two concrete high school characteristics on plans to major in STEM fields in college—a high school’s curriculum in STEM and gender segregation of extracurricular activities. These factors have a substantial effect on the gender gap in plans to major in STEM: a finding that is reaffirmed in a number of sensitivity analyses. Our focus on the high school context opens concrete avenues for policy intervention and is of central theoretical importance to understand the gender gap in orientations toward STEM fields.
The Undecided Respondent in Mandatory Voting Settings: a Venezuelan Exploration

jOLITICAL SCIENTISTS have devoted great energies to understanding individual choices in presidential elections. ' Studies, usually involving survey methods, have taught us a great deal about how people who report their choices reach their decisions. In contrast, we know little about respondents who report themselves undecided, except as indecisiveness has been analysed in the context of nonvoting (Hadley 1978; Wolfinger and Rosenstone 1980). This treatment is not surprising as earlier American evidence suggested that individuals who report themselves undecided in the middle of an intense political campaign are unlikely to vote (Campbell, Converse, Miller, and Stokes 1960). With the focus on who is going to vote for which candidate and why, undecided respondents become relegated to "missing data. " In the small but significant number of democracies with compulsory voting (Crewe 1981: 240), undecided respondents deserve serious attention. Since in mandatory voting systems undecided individuals eventually must cast their ballots, undecided respondents do become voters. This is recognized by pollsters and campaign strategists who devote great time and energy attempting to uncover the political motivations and preferences of the undecided. Campaign consultants assume that understanding undecided respondents is a key to winning elections. Political scientists concerned with electoral choice in obligatory voting systems have not matched the political consultants' concern with undecided respondents. This oversight may be explained in part by the methodological difficulty in dealing with subjects who respond "I don't know" to the quintessential question of most psephological research. The purpose of this paper is to examine the voting behavior and motivations of voters who report themselves undecided in preelection days surveys. We propose to show how undecided respondents can be studied and to demonstrate that a focus on the undecideds enhances the
Stabilizing hybrid switched motion control systems with an on-line trajectory generator

This paper suggests the idea of a universal method for stabilizing discrete-time hybrid switched-control systems of robot manipulators. The core of this idea is based on an on-line trajectory generation algorithm that is able to generate continuous command variables from any arbitrary state of motion. We define a measurable criterion to on-line detect an instability or a potential instability of the plant, and right after this criterion is fulfilled, we switch to the on-line trajectory generator that acts as an open-loop pose control submodule in the switched-system. The on-line trajectory generation algorithm guides the system under consideration of kinematic motion constraints to a desired target state of motion that can be specified beforehand (e.g., zero-velocity in a pre-defined position). Systems with one and more degrees of freedom are regarded in this paper; finally, real-world experimental results achieved with a six-joint industrial manipulator are presented in order to demonstrate the potential and the high practical relevance of this concept.