Miracle-dz/UniFAR-FTUs huggingface dataset:
Incentives Work: Getting Teachers to Come to School

We use a randomized experiment and a structural model to test whether monitoring and financial incentives can reduce teacher absence and increase learning in India. In treatment schools, teachers’ attendance was monitored daily using cameras, and their salaries were made a nonlinear function of attendance. Teacher absenteeism in the treatment group fell by 21 percentage points relative to the control group, and the children’s test scores increased by 0.17 standard deviations. We estimate a structural dynamic labor supply model and find that teachers respond strongly to financial incentives. Our model is used to compute cost-minimizing compensation policies. (JEL I21, J31, J45, O15)
Cure kinetics and thermal stability of micro and nanostructured thermosetting blends of epoxy resin and epoxidized styrene-block-butadiene-block-styrene triblock copolymer systems

The compatibility of styrene-block-butadiene-block-styrene (SBS) triblockcopolymer in epoxy resin is increased by the epoxidation of butadiene segment, using hydrogen peroxide in the presence of an in situ prepared catalyst in water/dichloroethane biphasic system. Highly epoxidized SBS (epoxy content SBS >26 mol%) give rise to nanostructured blends with epoxy resin. The cure kinetics of micro and nanostructured blends of epoxy resin [diglycidyl ether of bisphenol A; (DGEBA)]/amine curing agent [4,4′-diaminodiphenylmethane (DDM)] with epoxidized styrene-block-butadiene-block-styrene (eSBS 47 mol%) triblock copolymer has been studied for the first time using differential scanning calorimetry under isothermal conditions to determine the reaction kinetic parameters such as kinetic constants and activation energy. The cure reaction rate is decreased with increasing the concentration of eSBS in the blends and also with the lowering of cure temperature. The compatibility of eSBS in epoxy resin is investigated in detailed by Fourier transform infrared spectroscopy, optical and transmition electron microscopic analysis. The experimental data of the cure behavior for the systems, epoxy/DDM and epoxy/eSBS(47 mol%)/DDM show an autocatalytic behavior regardless of the presence of eSBS in agreement with Kamal's model. The thermal stability of cured resins is also evaluated using thermogravimetry in nitrogen atmosphere. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
A CCD imaging search for wide metal-poor binaries

We explored the regions within a radius of 25 �� around 473 nearby, low-metallicity G- to M-type stars using (VR)I optical filters and small-aperture telescopes. About 10% of the sample was searched up to angular separations of 90 �� . W e applied photometric and astrometric techniques to detect true physical companions to the targets. The great majority of the sample stars was drawn from the Carney-Latham surveys; their metallicities range from roughly solar to (Fe/H) = −3. 5d ex. Our I-band photometric survey detected objects that are between 0 and 5 mag fainter (completeness) than the target stars; the maximum dynamical range of our exploration is 9 mag. We also investigated the literature, and inspected images from the Digitized Sky Surveys to complete our search. By combining photometric and proper motion measurements, we retrieved 29 previously known companions, and identified 13 new proper motion companions. Near-infrared 2MASS photometry is provided for the great majority of them. Low-resolution optical spectroscopy (386-1000 nm) was obtained for eight of the new companion stars. These spectroscopic data confirm them as cool, late-type, metal-depleted dwarfs, with spectral classes from esdK7 to sdM3. After comparison with low-metallicity evolutionary models, we estimate the masses of the proper motion companion stars to be in the range 0.5-0.1 M� . They are moving around their primary stars at projected separations between ∼32 and ∼57 000 AU. These orbital sizes are very similar to those of solar-metallicity stars of the same spectral types. Our results indicate that about 15% of the metal-poor stars have stellar companions in wide orbits, which is in agreement with the binary fraction observed among main sequence G- to M-type stars and T Tauri stars.
Randomized, Double-Blind, Multicenter, Placebo-Controlled Study Evaluating the Effect of Aldosterone Antagonism With Eplerenone on Ventricular Remodeling in Patients With Mild-to-Moderate Heart Failure and Left Ventricular Systolic Dysfunction

Background—Aldosterone antagonism has been studied in patients with advanced heart failure (HF) and also in patients with post-myocardial infarction and left ventricular (LV) dysfunction with HF symptoms. Few data are available on effects of aldosterone antagonism in patients with mild-to-moderate HF. Methods and Results—In a multicenter, randomized, double-blind, placebo-controlled study in patients with mild-to-moderate HF and LV systolic dysfunction, patients with New York Heart Association class II/III HF and LV ejection fraction (EF) ≤35% were randomly assigned to receive eplerenone 50 mg/d versus placebo in addition to contemporary background therapy. Quantitative radionuclide ventriculograms to assess LV volumes and ejection fraction were performed at baseline and again after 9 months of double-blind treatment and were analyzed in a central core laboratory, blinded to treatment. The primary efficacy analysis was the between-group comparison of the change in LV end-diastolic volume index. Secondary analyses examined changes in LV end-systolic volume index and ejection fraction as well as markers of collagen turnover. Of the total 226 patients enrolled, 117 were randomly assigned to receive eplerenone and 109 to receive placebo. There was high use of contemporary background therapy at baseline, with >90% use of angiotensin-converting enzyme inhibitors and/or angiotensin receptor blockers and >90% use of &bgr;-blockers. Over 36 weeks of treatment, there was no apparent between-group difference in the changes in end-diastolic volume index or end-systolic volume index. There was a reduction in the collagen turnover marker procollagen type I N-terminal propeptide and plasma B-type natriuretic peptide in the eplerenone group compared with placebo (P=0.01 and P=0.04, respectively). There was no change in symptom status or quality-of-life measures. Conclusions—In a clinically stable, well-treated population of patients with mild-to-moderate HF symptoms and LV dysfunction, 36 weeks of treatment of aldosterone antagonism with eplerenone at a dose of 50 mg daily had no detectable effect on parameters of LV remodeling. Clinical Trial Registration—URL: http://www.clinicaltrials. gov. Unique identifier: NCT00082589.
Composites as friction materials: Recent developments in non‐asbestos fiber reinforced friction materials—a review

Replacement of conventional asbestos based friction materials has been called for because of bans on the use of asbestos. Research in this direction in the last decade has led to the development of more efficient asbestos-free friction materials for automobiles. Fiber reinforced polymers show great promise for applications in modern vehicles. This review article focuses on the recent developments in the application of composites as friction materials. The first part of the article contains brief information about brakes, their action, brake materials, their desired properties, etc. The second part deals with the recent developments in non-asbestos fiber reinforced friction materials.
The Effect of a Diabetes-Specific Cognitive Behavioral Treatment Program (DIAMOS) for Patients With Diabetes and Subclinical Depression: Results of a Randomized Controlled Trial

OBJECTIVE Subclinical depression is one of the most frequent mental comorbidities in patients with diabetes and is associated with a poorer long-term prognosis. Since there is a lack of specific intervention concepts for this patient group, a self-management–oriented group program (DIAMOS [Diabetes Motivation Strengthening]) was newly developed and evaluated in a randomized trial. RESEARCH DESIGN AND METHODS DIAMOS is composed of cognitive behavioral interventions aiming at the reduction of diabetes distress. The active control group (CG) received diabetes education. The primary outcome was depressive symptoms. Secondary outcomes were diabetes distress, well-being, self-care behavior, diabetes acceptance, diabetes treatment satisfaction, HbA1c, and subclinical inflammation. RESULTS Two hundred fourteen participants (mean age 43.3 ± 13.3 years, female sex 56.5%, type 2 diabetes 34.1%, mean diabetes duration 14.2 ± 10.5 years, HbA1c 8.9 ± 1.8%, BMI 28.7 ± 71 kg/m2) were randomized. The 12-month follow-up revealed a significantly stronger reduction of depressive symptoms (Center for Epidemiologic Studies Depression Scale score) in the DIAMOS group compared with the CG (Δ3.9 [95% CI 0.6–7.3], P = 0.021). Of the secondary variables, the Patient Health Questionnaire-9 (Δ1.7 [95% CI 0.2–3.2], P = 0.023), Problem Areas in Diabetes scale (Δ8.2 [95% CI 3.1–13.3], P = 0.002), and Diabetes Distress Scale scores (Δ0.3 [95% CI 0.1–0.5], P = 0.012) displayed significant treatment effects. Moreover, the risk of incident major depression in the DIAMOS group was significantly reduced (odds ratio 0.63 [95% CI 0.42–0.96], P = 0.028). Inflammatory variables were not substantially affected. CONCLUSIONS DIAMOS is more effective in lowering depressive symptoms and diabetes-related distress in diabetic patients with subclinical depression. DIAMOS also has a preventive effect with respect to the incidence of major depression.
Evolution versus Temporal Difference Learning for learning to play Ms. Pac-Man

This paper investigates various factors that affect the ability of a system to learn to play Ms. Pac-Man. For this study Ms. Pac-Man provides a game of appropriate complexity, and has the advantage that in recent years there have been many other papers published on systems that learn to play this game. The results indicate that Temporal Difference Learning (TDL) performs most reliably with a tabular function approximator, and that the reward structure chosen can have a dramatic impact on performance. When using a multi-layer perceptron as a function approximator, evolution outperforms TDL by a significant margin. Overall, the best results were obtained by evolving multi-layer perceptrons.
Numerical Simulation of Temperature–Voltage Relation in Electrical Contacts and Correction of Classical Kohlrausch’s Equation

The increase in temperature caused by Joule heat is a very important concern to the electrical interconnections. The maximum temperature of contacts in these interconnections is not easily measurable, but can be calculated by the temperature-voltage relation, which is also called Kohlrausch's equation. In this paper, we build a finite-element model of spherical copper contact pairs for thermal-electrical coupled analysis. The material properties of the model involved are closely dependent on the temperature. By comparing simulation results with the calculation of the temperature-voltage equation, the accuracy of Kohlrausch's equation has been verified. Furthermore, the effects of electric current, side surface heat convection coefficient, and Lorenz coefficient on Kohlrausch's equation are investigated explicitly. It is determined that the calculation error of Kohlrausch's equation could be attributed to the assumed constant Lorenz coefficient, and then a correction method for Kohlrausch's equation is proposed.
Correlations between epsilon'/epsilon and Rare K Decays in the Littlest Higgs Model with T-Parity

We calculate the CP-violating ratio epsilon'/epsilon in the Littlest Higgs model with T-parity (LHT) and investigate its correlations with the branching ratios for K_L -> pi^0 nu {bar nu}, K_L -> pi^0 l^+ l^- and K^+ -> pi^+ nu {bar nu}. The resulting correlations are rather strong in the case of K_L decays, but less pronounced in the case of K^+ -> pi^+ nu {bar nu}. Unfortunately, they are subject to large hadronic uncertainties present in epsilon'/epsilon, whose theoretical prediction in the Standard Model (SM) is reviewed and updated here. With the matrix elements of Q_6 (gluon penguin) and Q_8 (electroweak penguin) evaluated in the large-N limit and m_s^MS(2 GeV) = 100 MeV from lattice QCD, (epsilon'/epsilon)_SM turns out to be close to the data so that significant departures of Br(K_L -> pi^0 nu {bar nu}) and Br(K_L -> pi^0 l^+ l^-) from the SM expectations are unlikely, while Br(K^+ -> pi^+ nu {bar nu}) can be enhanced even by a factor 5. On the other hand, modest departures of the relevant hadronic matrix elements from their large-N values allow for a consistent description of epsilon'/epsilon within the LHT model accompanied by large enhancements of Br(K_L -> pi^0 nu {bar nu}) and Br(K_L -> pi^0 l^+ l^-), but only modest enhancements of Br(K^+ -> pi^+ nu {bar nu}).
Activity of Cefoperazone Against Ampicillin-Resistant Bacteria in Agar and Broth Dilution Tests

Examination of the activity of cefoperazone against ampicillin-resistant, gramnegative bacteria in agar dilution and simultaneously in broth dilution revealed that strains could be divided into three classes: class I strains were susceptible in agar (mean minimal inhibitory concentration [MIC], 0.5 mg/liter) as well as in broth dilution (mean MIC, 1.5 mg/liter), class II strains were susceptible in agar (MIC, 0.9 mg/liter), but resistant in broth dilution (MIC, 182 mg/liter); and class III strains were highly resistant in both test systems. Among 100 randomly selected ampicillin-resistant Escherichia coli cultures, 51 belonged to class I and 49 belonged to class II. Class III E. coli strains were much rarer. Similar results were obtained with cefamandole and cephalothin, but not with six other second-and third-generation cephalosporins. MICs of cefoperazone against cultures of all three classes were influenced by initial inoculum size. The inoculum effect was greatest with class II strains. Examination of bactericidal activity by cefoperazone showed killing of class I and class II E. coli strains and of class III strains of other genera during the first hours of incubation and regrowth after the drug was destroyed by the action of TEM β-lactamase (penicillinase). Representative class I bacteria produced 10 to 100 times less TEM β-lactamase than did class II strains. It appeared that the quantitative difference in TEM production was the reason for the different resistance phenotypes in class I and class II strains. Salmonella and Klebsiella strains of class III produced the same amounts of TEM β-lactamase as did class II E. coli strains. Probably, some factors other than β-lactamase contributed to the class III phenotype in these species.
Clustering Using Annealing Evolution: Application to Pixel Classification of Satellite Images

In this article an efficient clustering technique, that utilizes an effective integration of simulated annealing and evolutionary programming as the underlying search tool, is developed. During the evolution process, data points are redistributed among the clusters probabilistically so that points that are farther away from the cluster center have higher probabilities of migrating to other clusters than those which are closer to it. The superiority of the new clustering algorithm over the widely used K-means algorithm and those based on simulated annealing and conventional evolutionary programming is demonstrated for some real life data sets. Another real life application of the developed clustering technique in classifying the pixels of a satellite image of a part of the city of Mumbai is also provided.
Transcranial Doppler ultrasonography as a predictor of haemodynamically significant carotid stenosis

Transcranial Doppler (TCD) ultrasonography can detect evidence of collateral flow across the anterior communicating artery and/or the posterior communicating artery, which occurs when there is significant alteration of ‘inflow’ to the brain. The aim of the study was to determine the blood flow velocity produced by a carotid stenosis which produces this haemodynamic effect on the cerebral circulation and evokes collateral circulation.
Denoising an Image by Denoising Its Curvature Image

In this article we argue that when an image is corrupted by additive noise, its curvature image is less affected by it; i.e., the peak signal-to-noise ratio of the curvature image is larger. We speculate that, given a denoising method, we may obtain better results by applying it to the curvature image and then reconstructing from it a clean image, rather than denoising the original image directly. Numerical experiments confirm this for several PDE-based and patch-based denoising algorithms.
Dual Role of Carcinoembryonic Antigen-Related Cell Adhesion Molecule 1 in Angiogenesis and Invasion of Human Urinary Bladder Cancer

Here, we show that carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is expressed in umbrella cells of bladder urothelium but is down-regulated in superficial bladder cancer, such as histologic tumor stage a (pTa) and transitional cell carcinoma in situ (pTis). Concurrently, CEACAM1 is up-regulated in the endothelia of adjacent angiogenic blood vessels. Mimicking the CEACAM1 down-regulation in the urothelium, CEACAM1 was silenced in bladder cancer cell lines 486p and RT4 using the small interfering RNA technique. CEACAM1 down-regulation was confirmed at the protein level by Western blot analyses. CEACAM1 silencing leads to a significant up-regulation of vascular endothelial growth factor (VEGF)-C and VEGF-D in quantitative reverse transcription-PCR. Correspondingly, supernatants from the CEACAM1-overexpressing bladder cancer cell lines reduce, but those from CEACAM1 silencing induce endothelial tube formation and potentiate the morphogenetic effects of VEGF. These data suggest that the epithelial down-regulation of CEACAM1 induces angiogenesis via increased expression of VEGF-C and VEGF-D. Inversely, CEACAM1 is up-regulated in endothelial cells of angiogenic blood vessels. This in turn is involved in the switch from noninvasive and nonvascularized to invasive and vascularized bladder cancer. CEACAM1 appears to be a promising endothelial target for bladder cancer therapy.
3-choosability of triangle-free planar graphs with constraint on 4-cycles ∗

A graph is k-choosable if it can be colored whenever every vertex has a list of at least k available colors. A theorem by Grötzsch [2] asserts that every triangle-free planar graph is 3-colorable. On the other hand Voigt [10] gave such a graph which is not 3-choosable. We prove that every triangle-free planar graph such that 4-cycles do not share edges with other 4and 5-cycles is 3-choosable. This strengthens the Thomassen’s result [8] that every planar graph of girth at least 5 is 3-choosable. In addition, this implies that every triangle-free planar graph without 6and 7-cycles is 3-choosable.
k-NN Regression on Functional Data with Incomplete Observations

In this paper we study a general version of regression where each covariate itself is a functional data such as distributions or functions. In real applications, however, typically we do not have direct access to such data; instead only some noisy estimates of the true covariate functions/distributions are available to us. For example, when each covariate is a distribution, then we might not be able to directly observe these distributions, but it can be assumed that i.i. d. sample sets from these distributions are available. In this paper we present a general framework and a k-NN based estimator for this regression problem. We prove consistency of the estimator and derive its convergence rates. We further show that the proposed estimator can adapt to the local intrinsic dimension in our case and provide a simple approach for choosing k. Finally, we illustrate the applicability of our framework with numerical experiments.
Generation of a Cell Culture-Adapted Hepatitis C Virus with Longer Half Life at Physiological Temperature

Background We previously reported infectious HCV clones that contain the convenient reporters, green fluorescent protein (GFP) and Renilla luciferase (Rluc), in the NS5a-coding sequence. Although these viruses were useful in monitoring viral proliferation and screening of anti-HCV drugs, the infectivity and yield of the viruses were low. Methodology/Principal Findings In order to obtain a highly efficient HCV cultivation system, we transfected Huh7.5. 1 cells [1] with JFH 5a-GFP RNA and then cultivated cells for 20 days. We found a highly infectious HCV clone containing two cell culture-adapted mutations. Two cell culture-adapted mutations which were responsible for the increased viral infectivity were located in E2 and p7 protein coding regions. The viral titer of the variant was ∼100-fold higher than that of the parental virus. The mutation in the E2 protein increased the viability of virus at 37°C by acquiring prolonged interaction capability with a HCV receptor CD81. The wild-type and p7-mutated virus had a half-life of ∼2.5 to 3 hours at 37°C. In contrast, the half-life of viruses, which contained E2 mutation singly and combination with the p7 mutation, was 5 to 6 hours at 37°C. The mutation in the p7 protein, either singly or in combination with the E2 mutation, enhanced infectious virus production about 10–50-fold by facilitating an early step of virion production. Conclusion/Significance The mutation in the E2 protein generated by the culture system increases virion viability at 37°C. The adaptive mutation in the p7 protein facilitates an earlier stage of virus production, such as virus assembly and/or morphogenesis. These reporter-containing HCV viruses harboring adaptive mutations are useful in investigations of the viral life cycle and for developing anti-viral agents against HCV.
A nonenumerative algorithm to find the k longest (shortest) paths in a DAG

In this paper, we present a novel and efficient algorithm to find the k longest (shortest) paths between sources and sinks in a directed acyclic graph (DAG). The algorithm does not enumerate paths therefore it is especially useful for very large k values. It is based on the Valued-Sum-of-Product (VSOP) tool, which is an extension of Zero-suppressed Binary Decision Diagrams (ZBDDs). We assessed the performance of this algorithm with a DAG model of a path-intensive combinational circuit, viz. c6288, that has \sim10^{20} paths. We found that it took about 64 minutes to compute all paths in this DAG along with their lengths.
Acute Exercise Improves Prefrontal Cortex but not Hippocampal Function in Healthy Adults

Abstract The effects of acute aerobic exercise on cognitive functions in humans have been the subject of much investigation; however, these studies are limited by several factors, including a lack of randomized controlled designs, focus on only a single cognitive function, and testing during or shortly after exercise. Using a randomized controlled design, the present study asked how a single bout of aerobic exercise affects a range of frontal- and medial temporal lobe-dependent cognitive functions and how long these effects last. We randomly assigned 85 subjects to either a vigorous intensity acute aerobic exercise group or a video watching control group. All subjects completed a battery of cognitive tasks both before and 30, 60, 90, or 120 min after the intervention. This battery included the Hopkins Verbal Learning Test-Revised, the Modified Benton Visual Retention Test, the Stroop Color and Word Test, the Symbol Digit Modalities Test, the Digit Span Test, the Trail Making Test, and the Controlled Oral Word Association Test. Based on these measures, composite scores were formed to independently assess prefrontal cortex- and hippocampal-dependent cognition. A three-way mixed Analysis of Variance was used to determine whether differences existed between groups in the change in cognitive function from pre- to post-intervention testing. Acute exercise improved prefrontal cortex- but not hippocampal-dependent functioning, with no differences found between delay groups. Vigorous acute aerobic exercise has beneficial effects on prefrontal cortex-dependent cognition and these effects can last for up to 2 hr after exercise. (JINS, 2015, 21, 791–801)