Miracle-dz/UniFAR-FTUs huggingface dataset:
Do Credit Analysts Matter? The Effect of Analysts on Ratings, Prices, and Corporate Decisions

We find evidence of systematic optimism and pessimism among credit analysts, comparing contemporaneous ratings of the same firm across rating agencies. These biases carry through to debt prices and negatively predict future changes in credit spreads, consistent with mispricing. Moreover, they affect corporate policies: firms covered by more pessimistic analysts issue less debt, use more equity financing, and experience slower revenue growth. We find that MBAs provide higher quality ratings; however, optimism increases and accuracy decreases with tenure covering the firm. Our analysis uncovers a novel mechanism through which debt prices become distorted and demonstrates its effect on corporate decisions. JEL codes: G24, G32, G02, G12
The Dynamics of Self-Esteem in Adults Over a 6-Month Period: An Exploratory Study

In this exploratory study, the authors examined the dynamics of self-esteem in 8 adults over a 6-month period. Each participant (M age = 29.4 years, SD = 7.9, SEM = 2.8) completed a single item from the Physical Self Inventory (G. Ninot, M. Fortes, & D. Delignières, 2001) using a 10-cm visual analog scale (horizontal line), twice a day between 7:00 and 9:00 a.m. and between 7:00 and 9:00 p.m. Time series analyses, including autocorrelation and autoregressive integrated moving average (ARIMA) procedures, showed that global self-esteem dynamics were neither stable, stationary, nor random. The ARIMA procedures indicated that this perceived dimension functioned as a moving average (0, 1, 1) without a significant constant, thus suggesting a short-term dynamic adjustment. This pattern is a typical signature of a complex system submitted to several constraints and not an indication of personality trait or state.
Computational simulations demonstrate altered wall shear stress in aortic coarctation patients treated by resection with end-to-end anastomosis.

BACKGROUND Atherosclerotic plaque in the descending thoracic aorta (dAo) is related to altered wall shear stress (WSS) for normal patients. Resection with end-to-end anastomosis (RWEA) is the gold standard for coarctation of the aorta (CoA) repair, but may lead to altered WSS indices that contribute to morbidity. METHODS Computational fluid dynamics (CFD) models were created from imaging and blood pressure data for control subjects and age- and gender-matched CoA patients treated by RWEA (four males, two females, 15 ± 8 years). CFD analysis incorporated downstream vascular resistance and compliance to generate blood flow velocity, time-averaged WSS (TAWSS), and oscillatory shear index (OSI) results. These indices were quantified longitudinally and circumferentially in the dAo, and several visualization methods were used to highlight regions of potential hemodynamic susceptibility. RESULTS The total dAo area exposed to subnormal TAWSS and OSI was similar between groups, but several statistically significant local differences were revealed. Control subjects experienced left-handed rotating patterns of TAWSS and OSI down the dAo. TAWSS was elevated in CoA patients near the site of residual narrowings and OSI was elevated distally, particularly along the left dAo wall. Differences in WSS indices between groups were negligible more than 5 dAo diameters distal to the aortic arch. CONCLUSIONS Localized differences in WSS indices within the dAo of CoA patients treated by RWEA suggest that plaque may form in unique locations influenced by the surgical repair. These regions can be visualized in familiar and intuitive ways allowing clinicians to track their contribution to morbidity in longitudinal studies.
Recurrent Events of Positive Selection in Independent Drosophila Lineages at the Spermatogenesis Gene roughex

Our understanding of the role of positive selection in the evolution of genes with male-biased expression can be hindered by two observations. First, male-biased genes tend to be overrepresented among lineage-specific genes. Second, novel genes are prone to experience bursts of adaptive evolution shortly after their formation. A thorough study of the forces acting on male-biased genes therefore would benefit from phylogenywide analyses that could distinguish evolutionary trends associated with gene formation and later events, while at the same time tackling the interesting question of whether adaptive evolution is indeed idiosyncratic. Here we investigate the roughex (rux) gene, a dose-dependent regulator of Drosophila spermatogenesis with a C-terminal domain responsible for nuclear localization that shows a distinct amino acid sequence in the melanogaster subgroup. We collected polymorphism and divergence data in eight populations of six Drosophila species, for a total of 99 rux sequences, to study rates and patterns of evolution at this male-biased gene. Our results from two phylogeny-based methods (PAML and HyPhy) as well as from population genetics analyses (McDonald–Kreitman-based tests) indicate that amino acid replacements have contributed disproportionately to divergence, consistent with adaptive evolution at the Rux protein. Analyses based on extant variation show also the signature of recent selective sweeps in several of the populations surveyed. Most important, we detect the significant and consistent signature of positive selection in several independent Drosophila lineages, which evidences recurrent and concurrent events of adaptive evolution after rux formation.
What is the information content of dividend changes ? A new investigation of an old puzzle

In this paper we extend Grullon, Michaely, and Swaminathan (2002) and examine the hypothesis that dividend increases (decreases) are associated with decreases (increases) in firms’ information risk, which, together with the decreases (increases) in other systematic risks, contributes to the positive (negative) price changes surrounding dividend change announcements. Using Fama-French three-factor models augmented by an Information Risk factor, we find that, as predicted, dividend-decreasing firms exhibit an increase in information risk in the years after decrease announcements. However, our results on dividend-increasing firms are sensitive to the samples we use. Further analysis of the information characteristics of the dividend change firms indicates a reduction in analyst forecast dispersion and stock return volatility for dividend-increase firms and an increase in analyst forecast dispersion and stock return volatility for dividend-decrease firms in the years after dividend changes. Inconsistent with the prediction of traditional signaling models, dividend increase (decrease) firms do not exhibit an increase (a decrease) in future profitability.
Nuclear and Nucleolar Image Analysis of Human Breast Epithelial Cells Transformed by benzo[a]pyrene and Transfected with the c-Ha-ras oncogene

Changes in nuclear and nucleolar morphometric parameters were investigated by image analysis procedures in human breast MCF-10F epithelial cells expressing different stages of the tumourigenic progression after benzo[a]pyrene (BP) transformation (BP1, BP1-E, and BP1-E1 cell lines), and additionally transfected with the c-Ha-ras oncogene (BP1-Tras cell line). Nuclear pleomorphism was evident in all the transformed cells. The analysis of different morphometric parameters did not show a clear relationship between specific nuclear and nucleolar changes and the expression of the different stages of the tumourigenesis, with the exception of the nucleolar size, which could be associated to the expression of the tumourigenic phenotype, and a nucleolar area/nuclear area ratio, which discriminated the immortalized, the transformed, and the tumourigenic phenotypes from one another. The nuclear morphometric data established for the BP-transformed cells and for the cells additionally transfected with the c-Ha-ras oncogene were suggestive of complex and distinct morphofunctional mechanisms involving the in vitro transformation of the MCF-10F cells. The nuclear changes found in the BP1-Tras cell line were assumed to be related to the additional effects and/or enhanced genomic instability induced by transfection with the ras oncogene.
Landmark‐Guided Elastic Shape Analysis of Spherically‐Parameterized Surfaces

We argue that full surface correspondence (registration) and optimal deformations (geodesics) are two related problems and propose a framework that solves them simultaneously. We build on the Riemannian shape analysis of anatomical and star‐shaped surfaces of Kurtek et al. and focus on articulated complex shapes that undergo elastic deformations and that may contain missing parts. Our core contribution is the re‐formulation of Kurtek et al.'s approach as a constrained optimization over all possible re‐parameterizations of the surfaces, using a sparse set of corresponding landmarks. We introduce a landmark‐constrained basis, which we use to numerically solve this optimization and therefore establish full surface registration and geodesic deformation between two surfaces. The length of the geodesic provides a measure of dissimilarity between surfaces. The advantages of this approach are: (1) simultaneous computation of full correspondence and geodesic between two surfaces, given a sparse set of matching landmarks (2) ability to handle more comprehensive deformations than nearly isometric, and (3) the geodesics and the geodesic lengths can be further used for symmetrizing 3D shapes and for computing their statistical averages. We validate the framework on challenging cases of large isometric and elastic deformations, and on surfaces with missing parts. We also provide multiple examples of averaging and symmetrizing 3D models.
A role for mixed lineage kinases in granule cell apoptosis induced by cytoskeletal disruption

Microtubule disruption by colchicine induces apoptosis in selected neuronal populations. However, little is known about the upstream death signalling events mediating the neurotoxicity. We investigated first whether colchicine‐induced granule cell apoptosis activates the c‐Jun N‐terminal kinase (JNK) pathway. Cultured murine cerebellar granule cells were exposed to 1 µm colchicine for 24 h. Activation of the JNK pathway was detected by western blotting as well as immunocytochemistry using antibodies against phospho‐c‐Jun (p‐c‐Jun). Next, adult male rats were injected intracerebroventricularly with colchicine (10 µg), and JNK pathway activation in dentate granule cells (DGCs) was detected by antibodies against p‐c‐Jun. The second part of the study tested the involvement of mixed lineage kinases (MLK) as upstream activators of the JNK pathway in colchicine toxicity, using CEP‐1347, a potent MLK inhibitor. In vitro, significant inhibition of the JNK pathway, activated by colchicine, was achieved by 100–300 nm CEP‐1347, which blocked both activation of cell death proteases and apoptosis. Moreover, CEP‐1347 markedly delayed neurite fragmentation and cell degeneration. In vivo, CEP‐1347 (1 mg/kg) significantly prevented p‐c‐jun increase following injection of colchicine, and enhanced survival of DGCs. We conclude that colchicine‐induced neuronal apoptosis involves the JNK/MLK pathway, and that protection of granule cells can be achieved by MLK inhibition.
Evaluation of the Effect of a Continuous Treatment: A Machine Learning Approach with an Application to Treatment for Traumatic Brain Injury

Summary For a continuous treatment, the generalised propensity score (GPS) is defined as the conditional density of the treatment, given covariates. GPS adjustment may be implemented by including it as a covariate in an outcome regression. Here, the unbiased estimation of the dose–response function assumes correct specification of both the GPS and the outcome‐treatment relationship. This paper introduces a machine learning method, the ‘Super Learner’, to address model selection in this context. In the two‐stage estimation approach proposed, the Super Learner selects a GPS and then a dose–response function conditional on the GPS, as the convex combination of candidate prediction algorithms. We compare this approach with parametric implementations of the GPS and to regression methods. We contrast the methods in the Risk Adjustment in Neurocritical care cohort study, in which we estimate the marginal effects of increasing transfer time from emergency departments to specialised neuroscience centres, for patients with acute traumatic brain injury. With parametric models for the outcome, we find that dose–response curves differ according to choice of specification. With the Super Learner approach to both regression and the GPS, we find that transfer time does not have a statistically significant marginal effect on the outcomes. © 2015 The Authors. Health Economics Published by John Wiley & Sons Ltd.
Research on discrimination and health: an exploratory study of unresolved conceptual and measurement issues.

OBJECTIVES Our goal in this study was to better understand racial and socioeconomic status (SES) variations in experiences of racial and nonracial discrimination. METHODS We used 1999 and 2000 data from the YES Health Study, which involved a community sample of 50 Black and 50 White respondents drawn from 4 neighborhoods categorized according to racial group (majority Black or majority White) and SES (≤ 150% or > 250% of the poverty line). Qualitative and quantitative analyses examined experiences of discrimination across these neighborhoods. RESULTS More than 90% of Blacks and Whites described the meaning of unfair treatment in terms of injustice and felt certain about the attribution of their experiences of discrimination. These experiences triggered similar emotional reactions (most frequently anger and frustration) and levels of stress across groups, and low-SES Blacks and Whites reported higher levels of discrimination than their moderate-SES counterparts. CONCLUSIONS Experiences of discrimination were commonplace and linked to similar emotional responses and levels of stress among both Blacks and Whites of low and moderate SES. Effects were the same whether experiences were attributed to race or to other reasons.
Use of Interrupted Time-Series Method to Evaluate the Impact of Cigarette Excise Tax Increases in Pennsylvania, 2000–2009

Introduction Scientific evidence shows that cigarette price increases can significantly reduce smoking prevalence and smoking initiation among adolescents and young adults. However, data are lacking regarding the effectiveness of increasing Pennsylvania’s cigarette tax to reduce smoking and/or adverse health effects of smoking. The objective of our study was to assess the impact of cigarette tax increases and resulting price increases on smoking prevalence, acute myocardial infarction (AMI) and asthma hospitalization rates, and sudden cardiac death (SCD) rates in Pennsylvania. Methods We used segmented regression analyses of interrupted time series to evaluate the level and trend changes in Pennsylvania adults’ current smoking prevalence, age-adjusted AMI and asthma hospitalization rates, age-specific asthma hospitalization rates, and age-adjusted SCD rates following 2 cigarette excise tax increases. Results After the first excise tax increase, no beneficial effects were noted on the outcomes of interest. The second tax increase was associated with significant declines in smoking prevalence for people aged 18 to 39, age-adjusted AMI hospitalization rates for men, age-adjusted asthma hospitalizations rates, and SCD rates among men. Overall smoking prevalence declined by 5.2% (P = .01), with a quarterly decrease of 1.4% (P = .01) for people aged 18 to 39 years. The age-adjusted AMI hospitalization rate for men showed a decline of 3.87/100,000 population (P = .04). The rate of age-adjusted asthma hospitalizations decreased by 10.05/100,000 population (P < .001), and the quarterly trend decreased by 3.21/100,000 population (P < .001). Quarterly SCD rates for men decreased by 1.34/100,000 population (P < .001). Conclusion An increase in the price of cigarettes to more than $4 per 20-cigarette pack was associated with a significant decrease in smoking among younger people (aged 18–39). Decreases were also seen in asthma hospitalizations and men’s age-adjusted AMI hospitalization and SCD rates. Further research and policy development regarding the effect of cigarette taxes on tobacco consumption should be cognizant of the psychological tipping points at which overall price affects smoking patterns.
Automatic synchronization and distribution of biological databases and software over low-bandwidth networks among developing countries

UNLABELLED Bioinformatics involves the collection, organization and analysis of large amounts of biological data, using networks of computers and databases. Developing countries in the Asia-Pacific region are just moving into this new field of information-based biotechnology. However, the computational infrastructure and network bandwidths available in these countries are still at a basic level compared to that in developed countries. In this study, we assessed the utility of a BitTorrent-based Peer-to-Peer (btP2P) file distribution model for automatic synchronization and distribution of large amounts of biological data among developing countries. The initial country-level nodes in the Asia-Pacific region comprised Thailand, Korea and Singapore. The results showed a significant improvement in download performance using btP2P--three times faster overall download performance than conventional File Transfer Protocol (FTP). This study demonstrated the reliability of btP2P in the dissemination of continuously growing multi-gigabyte biological databases across the three Asia-Pacific countries. The download performance for btP2P can be further improved by including more nodes from other countries into the network. This suggests that the btP2P technology is appropriate for automatic synchronization and distribution of biological databases and software over low-bandwidth networks among developing countries in the Asia-Pacific region. AVAILABILITY http://everest.bic. nus.edu. sg/p2p/
The Swift X-Ray Flaring Afterglow of GRB 050607

The unique capability of the Swift satellite to perform a prompt and autonomous slew to a newly detected gamma-ray burst (GRB) has yielded the discovery of interesting new properties of GRB X-ray afterglows, such as the steep early light-curve decay and the frequent presence of flares detected up to a few hours after the GRB trigger. We present observations of GRB 050607, the fourth case of a GRB discovered by Swift with flares superimposed on the overall fading X-ray afterglow. The flares of GRB 050607 were not symmetric as in previously reported cases, showing a very steep rise and a shallower decay, similar to the fast rise, exponential decay that are frequently observed in the gamma-ray prompt emission. The brighter flare had a flux increase by a factor of ~25, peaking for 30 s at a count rate of approximately 30 counts s-1, and it presented hints of additional short-timescale activity during the decay phase. There is evidence of spectral evolution during the flares. In particular, at the onset of the flares the observed emission was harder, with a gradual softening as each flare decayed. The very short timescale and the spectral variability during the flaring activity are indicators of possible extended periods of energy emission by the GRB central engine. The flares were followed by a phase of shallow decay, during which the forward shock was being refreshed by a long-lived central engine or by shells of lower Lorentz factors, and by a steepening after approximately 12 ks to a decay slope considered typical of X-ray afterglows.
Secure Physical Layer Key Generation Schemes: Performance and Information Theoretic Limits

There is growing interest in wireless security methods that provide strong or even perfect secrecy by taking advantage of features of the physical propagation channel. In advantage-based methods, high channel quality in an average or opportunistic sense is exploited between two legitimate nodes, such that nonzero secrecy capacity can be achieved. Since such methods require bounds on the quality of the eavesdropper channel, they are somewhat impractical. Secret key generation based on tracking channel evolution in time division duplex systems is a more attractive option, where two nodes generate secret key bits based on a mutually known random channel. Since the eavesdropper channel is typically independent of the legitimate channel, the key can only be broken by brute force attacks, which are difficult when new keys are continuously generated. In this paper, the information theoretic limits of key generation schemes are investigated, based on the level of estimation error, temporal correlation, and dependence of the eavesdropper and legitimate channels. Three practical candidate key generation schemes are also considered: channel quantization and channel quantization with guardband.
An Assessment of the Chondroprotective Effects of Intra-Articular Application of Statin and Tetracycline on Early-Stage Experimental Osteoarthritis

Objectives. To compare the effects of intra-articular application of statin and tetracyclines on cartilage and synovial tissue on experimental osteoarthritis. Methods. Osteoarthritis was created in 30 rabbits of 3 groups. The control group received saline intra-articularly, statin group, atorvastatin and the tetracycline group, doxycycline once a week for 3 weeks. Chondral and synovial tissues were evaluated macroscopically and histopathologically. Results. Macroscopic evaluation determined mean values of control group 3.0, statin group 0.56, and tetracycline group 2.5. Histopathological evaluations determined mean values; femoral medial condyle cartilage tissue, control group, 14.60 ± 1.00, statin group 2.20 ± 1.30, tetracycline group 12.7 ± 5.39: tibia medial plateau, control group, 14.33 ± 8.68, statin group 2.89 ± 1.96, tetracycline group, 15.90 ± 7.03: synovial tissue, control group 12.22 ± 3.63, statin group 4.33 ± 2.69, tetracycline group 10.70 ± 2.62. Average values of synovial tissue cell layer thickness were control group 14.46 ± 2.35 μm, statin group 10.56 ± 1.01 μm, tetracycline group 12.80 ± 0.79 μm. All measurements showed statistically significant differences between statin and control groups (P < 0.05) but not between tetracycline and control groups (P > 0.05). Conclusions. Tetracycline has little effect due to chemical modification requirement, and the effect is dose dependent. Statins have chondroprotective effects, so may become a novel therapeutic agent in osteoarthritis management after chemical processing.