Miracle-dz/UniFAR-FTUs huggingface dataset:
Correcting the bias of clerkship timing on academic performance.

OBJECTIVES To document the time-of-year bias in National Board of Medical Examiners subject examination (NBME) scores in a third-year pediatrics clerkship and to develop a grading method that neutralizes the bias. DESIGN Interventional modeling of final grades. SETTING University-based medical school. SUBJECTS AND METHODS During each of the past 3 academic years, we conducted six 2-month pediatric clerkships for third-year students. To counter the time-of-year bias, NBME scores, clinical evaluations, and departmental examination scores for the current rotation were pooled with those from the rotations from the same time of year during the previous 2 years. Final grades for the current rotation were determined by cutoff points derived from that entire 3-year pool. We analyzed this approach by testing the time-of-year effects on NBME scores, clinical evaluations, and final grades while maintaining step 1 of the US Medical Licensing Examination as a preclinical baseline control. RESULTS The scores for step 1 of the US Medical Licensing Examination did not differ significantly by time of year. Clinical evaluations and NBME scores showed significant upward trends as the academic year progressed. By contrast, according to design, final grades showed no significant time-of-year trend. CONCLUSIONS Our results support previous reports of significant improvements in NBME scores across the academic year. Our method of computing final grades corrects for this time-of-year bias by judging students only in relation to those who took the rotation at the same time of year. It is our belief that the prevalence and significance of the time-of-year trend warrants such an adjustment in grading to help minimize the academic disadvantage faced by students early in their clinical training.
A topological analysis of high-contrast patches in natural images

In this paper, we study qualitative topological analysis of spaces of natural images locally. We apply the techniques of computational topology to the space of 3×3, 4×4, 5×5, 6×6 and 7×7 high-contrast patches. We show that in each case there is a subspace of the space of all high-contrast patches that is topologically equivalent to the Klein bottle and we found that the size of the largest subspace having the Klein bottle’s homology decreases with increasing of the size of patches. The data sets used in this paper are different from that discussed in the paper ”on the local behavior of spaces of natural images”, we conformed our findings by applying the same methods to the different sizes patches. c ⃝2016 All rights reserved.
Collisional Dark Matter and the Structure of Dark Halos

We study how the internal structure of dark halos is affected if cold dark matter particles are assumed to have a large cross section for elastic collisions. We identify a cluster halo in a large cosmological N-body simulation and resimulate its formation with progressively increasing resolution. We compare the structure found in the two cases in which dark matter is treated as collisionless or as a fluid. For the collisionless case, the overall ellipticity of the cluster, the central density cusp, and the amount of surviving substructure are all similar to those found in earlier high-resolution simulations. Collisional dark matter results in a cluster that is more nearly spherical at all radii, has a steeper central density cusp, and has less—but still substantial—surviving substructure. As in the collisionless case, these results for a "fluid" cluster halo are expected to carry over approximately to smaller mass systems. The observed rotation curves of dwarf galaxies then argue that self-interacting dark matter can only be viable if intermediate cross sections produce structure that does not lie between the extremes we have simulated.
CTLA-4 is a second receptor for the B cell activation antigen B7

Functional interactions between T and B lymphocytes are necessary for optimal activation of an immune response. Recently, the T lymphocyte receptor CD28 was shown to bind the B7 counter-receptor on activated B lymphocytes, and subsequently to costimulate interleukin 2 production and T cell proliferation. CTLA-4 is a predicted membrane receptor from cytotoxic T cells that is homologous to CD28 and whose gene maps to the same chromosomal band as the gene for CD28. It is not known, however, if CD28 and CTLA-4 also share functional properties. To investigate functional properties of CTLA-4, we have produced a soluble genetic fusion between the extracellular domain of CTLA-4 and an immunoglobulin C gamma chain. Here, we show that the fusion protein encoded by this construct, CTLA4Ig, bound specifically to B7-transfected Chinese hamster ovary cells and to lymphoblastoid cells. CTLA4Ig also immunoprecipitated B7 from cell surface 125I-labeled extracts of these cells. The avidity of 125I-labeled B7Ig fusion protein for immobilized CTLA4Ig was estimated (Kd approximately 12 nM). Finally, we show that CTLA4Ig was a potent inhibitor of in vitro immune responses dependent upon cellular interactions between T and B lymphocytes. These findings provide direct evidence that, like its structural homologue CD28, CTLA- 4 is able to bind the B7 counter-receptor on activated B cells. Lymphocyte interactions involving the B7 counter-receptor are functionally important for alloantigen responses in vitro.
Investigations of Mesoscopic Complexity of Small Ice Crystals in Midlatitude Cirrus

During the Mid‐Latitude CIRRUS campaign small (<50 μm) ice crystals were characterized for their mesoscopic complexity using the Small Ice Detector Mk. 3. It was found that the majority (76%) of all measured small ice crystals were complex. Although some differences were found between the distributions of the complexity parameters between different cloud systems, no real correlation between the mesoscopic complexity and cloud formation mechanisms (liquid origin or in situ) was found. Some decrease in mesoscopic complexity was detected during those missions affected by Saharan dust outbreaks. The link between the crystal growth conditions and the observed mesoscopic complexity was investigated in a case study of an in situ cirrus with the help of trajectory analysis. A relatively weak correlation of r = 0.33 was found between the mesoscopic complexity and the maximum supersaturation with respect to ice along the ice particle trajectory.
1H-MR spectroscopy and gray matter volume of the anterior cingulate cortex in schizophrenia

Schizophrenic and normal control subjects were examined using both 1H-magnetic resonance spectroscopy (MRS) and structural MR imaging, in order to accurately assess the partial volume within the spectroscopic volume of interest (VOI) in the anterior cingulate cortex. The gray matter volume within VOI correlated positively with the N-acetyl-aspartate (NAA) to choline (Cho) ratio in schizophrenics only, not in controls. Schizophrenic patients had a reduced NAA/Cho ratio and an elevated Cho/creatine ratio compared to controls after the partial volume effect was eliminated. There was a significant negative correlation between the NAA/Cho ratio and the severity of blunted affect symptom in schizophrenics. These results provide further support to the idea that the measures of 1H-MRS indicate not only neuronal loss but also neuronal dysfunction in schizophrenia.
Towards applied theories based on computability logic

Abstract Computability logic (CL) is a recently launched program for redeveloping logic as a formal theory of computability, as opposed to the formal theory of truth that logic has more traditionally been. Formulas in it represent computational problems, “truth” means existence of an algorithmic solution, and proofs encode such solutions. Within the line of research devoted to finding axiomatizations for ever more expressive fragments of CL, the present paper introduces a new deductive system CL12 and proves its soundness and completeness with respect to the semantics of CL. Conservatively extending classical predicate calculus and offering considerable additional expressive and deductive power, CL12 presents a reasonable, computationally meaningful, constructive alternative to classical logic as a basis for applied theories. To obtain a model example of such theories, this paper rebuilds the traditional, classical-logicbased Peano arithmetic into a computability-logic-based counterpart. Among the purposes of the present contribution is to provide a starting point for what, as the author wishes to hope, might become a new line of research with a potential of interesting findings—an exploration of the presumably quite unusual metatheory of CL-based arithmetic and other CL-based applied systems.
Platelet concentrate injection improves Achilles tendon repair in rats

BACKGROUND Blood platelets release a cocktail of growth factors when activated, some of which are thought to initiate and stimulate repair. EXPERIMENT AND FINDINGS We studied whether a platelet concentrate injection would improve Achilles tendon repair in an established rat model. The Achilles tendon was transected and a 3 mm segment removed. After 6 h, a platelet concentrate was injected percutaneously into the hematoma. This increased tendon callus strength and stiffness by about 30% after 1 week, which persisted for as long as 3 weeks after the injection. At this time, the mechanical testing indicated an improvement in material characteristics--i.e., greater maturation of the tendon callus. This was confirmed by blinded histological scoring. INTERPRETATION Platelet concentrate may prove useful for the treatment of Achilles tendon ruptures.
Regulation of Angiotensin II-induced Phosphorylation of STAT3 in Vascular Smooth Muscle Cells*

Ligand binding to the angiotensin II (Ang II) AT1 receptor on vascular smooth muscle cells (VSMCs) activates the Janus-activated kinase (JAK)/signal transducers and activators of transcription (STAT) pathway. We have shown previously that the JAK2 tyrosine kinase and the Src family p59 Fyn tyrosine kinase are required for Ang II-induced STAT1 tyrosine phosphorylation in VSMCs. The mitogen-activated protein kinase phosphatase, MKP-1, is required for STAT1 tyrosine dephosphorylation. In the present study, using specific enzyme inhibitors and antisense oligonucleotides, we show that Ang II-induced tyrosine phosphorylation and nuclear translocation of STAT3 in VSMCs is mediated by p60 c-Src, whereas tyrosine dephosphorylation is mediated by calcineurin. Calcineurin is activated in response to Ang II stimulation of VSMCs and is translocated to the nucleus. In addition, we show that Ang II-induced serine phosphorylation of STAT3 in VSMCs is mediated by mitogen-activated protein kinase and that dephosphorylation is mediated by protein phosphatase 2A (PP2A). PP2A translocates to the nucleus in response to Ang II stimulation of VSMCs and forms a complex with STAT3 in an Ang II-dependent manner.
The Statistical Properties of Host Load (Extended Version)

Abstract : Understanding how host load changes over time is instrumental in predicting the execution time of tasks or jobs, such as in dynamic load balancing and distributed soft real-time systems. To improve this understanding, we collected week-long, 1 Hz resolution traces of the Digital Unix 5 second exponential load average on over 35 different machines including production and research cluster machines, compute servers, and desktop workstations. Separate sets of traces were collected at two different times of the year. The traces capture all of the dynamic load information available to user-level programs on these machines. We present a detailed statistical analysis of these traces here, including summary statistics, distributions, and time series analysis results. Two significant new results are that load is self-similar and that it displays epochal behavior. All of the traces exhibit a high degree of self-similarity with Hurst parameters ranging from 0.73 to 0.99, strongly biased toward the top of that range. The traces also display epochal behavior in that the local frequency content of the load signal remains quite stable for long periods of time (150-450 seconds mean) and changes abruptly at epoch boundaries. Despite these complex behaviors, we have found that relatively simple linear models are sufficient for short-range host load prediction.
Oxidation photochemistry in the Southern Atlantic boundary layer: Unexpected deviations of photochemical steady state

Abstract. Ozone (O 3 ) is a photochemical oxidant, an air pollutant and a greenhouse gas. As the main precursor of the hydroxyl radical (OH) it strongly affects the oxidation power of the atmosphere. The remote marine boundary layer (MBL) is considered an important region in terms of chemical O 3 loss; however surface-based atmospheric observations are sparse and the photochemical processes are not well understood. To investigate the photochemistry under the clean background conditions of the Southern Atlantic Ocean, ship measurements of NO, NO 2 , O 3 , J NO 2 , J(O 1 D), HO 2 , OH, RO x and a range of meteorological parameters were carried out. The concentrations of NO and NO 2 measured on board the French research vessel Marion-Dufresne (28° S–57° S, 46° W–34° E) in March 2007, are among the lowest yet observed. The data is evaluated for consistency with photochemical steady state (PSS) conditions, and the calculations indicate substantial deviations from PSS (Φ>1). The deviations observed under low NO x conditions (5–25 pptv) demonstrate a remarkable upward tendency in the Leighton ratio (used to characterize PSS) with increasing NO x mixing ratio and J NO 2 intensity. It is a paradigm in atmospheric chemistry that OH largely controls the oxidation efficiency of the atmosphere. However, evidence is growing that for unpolluted low-NO x (NO + NO 2 ) conditions the atmospheric oxidant budget is poorly understood. Nevertheless, for the very cleanest conditions, typical for the remote marine boundary layer, good model agreement with measured OH and HO 2 radicals has been interpreted as accurate understanding of baseline photochemistry. Here we show that such agreement can be deceptive and that a yet unidentified oxidant is needed to explain the photochemical conditions observed at 40°–60° S over the Atlantic Ocean.
Pioglitazone and metformin in obese women with polycystic ovary syndrome not optimally responsive to metformin.

BACKGROUND In an observational study of 13 women with polycystic ovary syndrome (PCOS) not optimally responsive to metformin diet, we assessed the efficacy and safety of addition of pioglitazone. We also compared these 13 women to 26 women with PCOS, who were responsive to metformin diet, matched by age and by pre- treatment menstrual history and not different by obesity categories. METHODS Prospectively, as outpatients, with diet constant [1500-2000 calorie (depending on entry body mass index), 26% protein, 44% carbohydrate, 30% fat], metformin (2.55 g/day) was given for 12 months to 39 women, 13 not optimally responsive, 26 responsive to metformin diet, followed by addition of pioglitazone (45 mg/day) for 10 months in the 13 non-responders. Outcome measures included changes in sex hormones, insulin, insulin resistance (IR), insulin secretion, high density lipoprotein cholesterol, weight, and menstrual status. RESULTS In 13 non-responders, on metformin diet, median serum insulin fell (21 to 16 microIU/ml, P<0.05) and insulin secretion fell from 251 to 200 (P<0.01); weight, dehydroepiandrosterone sulphate (DHEAS), testosterone and IR were unchanged (P> or =0.07). Compared with 14% pre- treatment, on metformin diet, expected menses occurred 46% of the time at 3 months (P=0.05), 38% at 6 months (P=0.07), 27% at 9 months, and 24% at 12 months. In 26 responders, on metformin diet, median weight fell (93 to 87 kg), testosterone fell (50 to 32 ng/dl), insulin fell (26 to 16 microIU/ml), IR fell (5.32 to 3.45) and insulin secretion fell (351 to 271) (P< or =0.017 for all). The occurrence of expected menses in the 26 responders was 2.5-fold higher than in the 13 non-responders (P<0.0001). In 11 non-responders, on pioglitazone + metformin diet over 10 months versus antecedent metformin diet, DHEAS fell (211 to 171 microg/dl, P=0.02), insulin fell (16 to 10 microIU/ml, P= 0.001), IR fell (3.37 to 1.73, P=0.002), insulin secretion fell (217 to 124, P=0.004), sex hormone-binding globulin rose (31 to 43 nmol/l, P=0.006), and HDL cholesterol rose (38 to 42 mg/dl, P=0.003). On pioglitazone + metformin diet, the occurrence of expected menses was 2-fold higher than on metformin diet (P<0.0001). CONCLUSIONS In women with PCOS who failed to respond optimally to metformin, when pioglitazone was added, insulin, glucose, IR, insulin secretion, and DHEAS fell, HDL cholesterol and sex hormone-binding globulin rose, and menstrual regularity improved, without adverse side-effects.
Body Fat Distribution and Risk of Cardiovascular Disease: An Update

Epidemiological, clinical, and mechanistic preclinical studies conducted in the field of cardiovascular medicine have led to remarkable progress in our understanding of nonmodifiable and modifiable risk factors for cardiovascular disease (CVD). For instance, although the prevalence of CVD had reached devastating levels in the 1950s, proper focus on the major CVD risk factors first identified at the time, such as smoking, hypertension, and high cholesterol levels, has allowed these risk factors to be targeted both at the clinical level and through public health policies.1 As a consequence, coronary heart disease mortality has decreased by ≈50% over the past 50 years.2 Ford et al2 have suggested that better screening and medical management of these CVD risk factors and the medical procedures developed to treat the various acute manifestations of CVD have had a favorable impact on its related mortality rates. However, the current overconsumption of processed and energy-dense food products of poor nutritional value combined with our sedentary lifestyle have contributed to the emergence of new drivers of CVD risk: obesity and type 2 diabetes mellitus (Figure 1). 3,4 It has been proposed that our medical progress at tackling CVD could be offset, at least to a certain extent, by the dramatic consequences of our toxic lifestyle, which includes poor nutrition or excess caloric consumption and a sedentary lifestyle, both leading to obesity and type 2 diabetes mellitus.2 Figure 1. Some of the alterations in the metabolic risk profile that have been found to be related to abdominal obesity assessed by anthropometry and later to excess visceral adiposity/ectopic fat assessed by imaging techniques. This constellation of metabolic abnormalities increases the risk of type 2 diabetes mellitus and of various cardiovascular outcomes. CVD indicates cardiovascular disease; HDL, high-density lipoprotein; LDL, low-density lipoprotein. Thus, the mosaic of modifiable …
Sino-Nasal 5 Questionnaire is Associated with Poor Asthma Control in Children with Asthma

Up to 80% of asthmatic children may experience upper airway symptoms which are often perceived as coming from the lower airways. Currently, there are no validated questionnaires to assess upper airway contribution to pediatric asthma symptoms. The Sino-Nasal 5 (SN-5) questionnaire was previously validated for identifying radiographic confirmed sinus disease in children. In this study, we hypothesize that significant SN-5 scores (≥3.5) are associated with abnormal National Asthma Education and Prevention Program (NAEPP) based asthma impairment and control in asthmatic children. Retrospective data collected on children with asthma referred for pulmonary evaluation included age, gender, ethnicity, NAEPP asthma severity, asthma control (Test for Respiratory and Asthma Control in Kids (TRACK) < 5 years, Asthma Control Test (ACT) 5 years) and pulmonary function testing. Associations between SN-5 scores and asthma impairment and control were identified. Seventy-six children were evaluated; 38% were female with a mean age of 6.9 years. Significant SN-5 scores were associated with decreased control of daytime symptoms (odds ratio (OR): 0.16 (95% confidence interval (CI): 0.06–0.44)), night time awakenings (0.09 (0.03–0.29)), activity interference (0.2 (0.06–0.68)), NAEPP defined asthma control (0.32 (0.12–0.85)) and poor asthma control based on TRACK (p < 0.001) and ACT (p < 0.001). This suggests upper airways may play a larger role in perceived lower airway symptoms, and SN-5 may be beneficial in assessing the contribution of upper airway conditions on asthma control.
Reliable life calculation of circuit breaker based on FTA and reliability function

Reliable life is defined as the average operation time of power equipment in a given reliability, and it is a significant parameter in reliability evaluation. This paper presents a reliable life calculation method for SF6 circuit breakers. The reliability evaluation model is established based on Fault Tree Analysis (FTA) method. From FTA, all the bottom events which cause top event (failure of the SF6 circuit breaker) are found. To estimate the reliability by inspection results and test results of the circuit breakers, Health Index (HI) is presented to calculate the failure probability of each bottom event, then the reliability of the top event is obtained. Collecting the failure probability and the age data of different SF6 circuit breakers with the same type in power system, the data is applied to estimate the reliability function of two parameters Weibull distribution by the least square method. Finally, the reliable life of the SF6 circuit breaker in a given reliability is estimated after inversion calculation by reliability function. To make further understanding of the method, an application example is presented, and the calculation result shows the effectiveness and accuracy of the model. According to the detailed analysis, the reliable life has more advantage than the physics life to reflect the reliability level of the power equipment.
Effect of exogenous bovine growth hormone and ovariectomy on prepubertal mammary growth, serum hormones and acute in-vitro proliferative response of mammary explants from Holstein heifers.

Sixteen prepubertal Holstein Friesian heifers were used to study the effect of long-term administration of bovine GH (bGH) on mammary development in intact and ovariectomized heifers. Eight heifers were ovariectomized at 2.5 months of age. Four intact and four ovariectomized heifers received subcutaneous injection of bGH (15 mg/day) for 15 weeks starting at 176 +/- 3 days of age (147 +/- 3 kg body weight), while the remaining eight heifers received an equal volume of excipient. Blood samples were collected weekly from 2 months of age. Heifers were slaughtered on the day after the last injection of bGH or excipient. Mammary gland development was quantified by dissection, chemical analysis and computer tomographic scanning. Mammary growth response at the time of slaughter was examined in cultures with explants prepared from parenchyma. Histological and histoautoradiographic studies with explants were performed. Treatment with bGH resulted in a significantly (P < 0.05) smaller mammary gland because of a reduced amount of extraparenchymal tissue. Ovariectomy markedly reduced the amount of parenchymal tissue. Growth response in mammary explants showed no treatment differences, suggesting that the decreased amount of parenchyma in ovariectomized heifers was caused by a decrease in mammary cell proliferation occurring some time prior to slaughter. The histological composition of mammary parenchyma was not changed by bGH treatment. However, ovariectomy resulted in less epithelial tissue (P < 0.001) and lumen (P < 0.05) and more stroma (P < 0.001), expressed as percentage tissue area. Serum hormone concentrations of bGH and insulin-like growth factor-I (IGF-I) were increased by bGH treatment in both intact and ovariectomized heifers. (ABSTRACT TRUNCATED AT 250 WORDS)