Miracle-dz/UniFAR-FTUs huggingface dataset:
PERSPECTIVE: SEXUAL CONFLICT AND SEXUAL SELECTION: CHASING AWAY PARADIGM SHIFTS

Abstract Traditional models of sexual selection propose that partner choice increases both average male and average female fitness in a population. Recent theoretical and empirical work, however, has stressed that sexual conflict may be a potent broker of sexual selection. When the fitness interests of males and females diverge, a reproductive strategy that increases the fitness of one sex may decrease the fitness of the other sex. The chase-away hypothesis proposes that sexual conflict promotes sexually antagonistic, rather than mutualistic, coevolution, whereby manipulative reproductive strategies in one sex are counteracted by the evolution of resistance to such strategies in the other sex. In this paper, we consider the criteria necessary to demonstrate the chase-away hypothesis. Specifically, we review sexual conflict with particular emphasis on the chase-away hypothesis; discuss the problems associated with testing the predictions of the chase-away hypothesis and the extent to which these predictions and the predictions of traditional models of sexual selection are mutually exclusive; discuss misconceptions and mismeasures of sexual conflict; and suggest an alternative approach to demonstrate sexual conflict, measure the intensity of sexually antagonistic selection in a population, and elucidate the coevolutionary trajectories of the sexes.
Tas Like Me: Racial Interactions between Graduate Teaching Assistants and Undergraduates

Over the past 40 years, higher education institutions in the U.S. have experienced a dramatic shift in the racial composition of students enrolled in both undergraduate and graduate programs. Using administrative data from a large, diverse university in California, we identify the extent to which the academic outcomes of undergraduates are affected by the race/ethnicity of their graduate student teaching assistants (TAs). To overcome selection issues in course taking, we exploit the timing of TA assignments, which occur after students enroll in a course, and we estimate models with both class and student fixed effects. Results show a positive and significant increase in course grades when students are assigned TAs of a similar race/ethnicity. These effects are largest in classes where TAs are given advanced copies of exams and when exams had no multiple choice questions. We also find that assignment to similar race TAs positively affect both section and office hour attendance, suggesting that TA-student match quality and role model effects are the primary drivers of the results.
Applying a Locally Linear Embedding Algorithm for Feature Extraction and Visualization of MI-EEG

Robotic-assisted rehabilitation system based on Brain-Computer Interface (BCI) is an applicable solution for stroke survivors with a poorly functioning hemiparetic arm. The key technique for rehabilitation system is the feature extraction of Motor Imagery Electroencephalography (MI-EEG), which is a nonlinear time-varying and nonstationary signal with remarkable time-frequency characteristic. Though a few people have made efforts to explore the nonlinear nature from the perspective of manifold learning, they hardly take into full account both time-frequency feature and nonlinear nature. In this paper, a novel feature extraction method is proposed based on the Locally Linear Embedding (LLE) algorithm and DWT. The multiscale multiresolution analysis is implemented for MI-EEG by DWT. LLE is applied to the approximation components to extract the nonlinear features, and the statistics of the detail components are calculated to obtain the time-frequency features. Then, the two features are combined serially. A backpropagation neural network is optimized by genetic algorithm and employed as a classifier to evaluate the effectiveness of the proposed method. The experiment results of 10-fold cross validation on a public BCI Competition dataset show that the nonlinear features visually display obvious clustering distribution and the fused features improve the classification accuracy and stability. This paper successfully achieves application of manifold learning in BCI.
Fractures of the radial head and neck treated with radial head excision.

BACKGROUND The reported long-term outcomes of the treatment of radial head and neck fractures with excision of the radial head have been mixed. The purpose of the present study was to evaluate the long-term outcomes of primary or delayed radial head excision for the treatment of these fractures. METHODS Sixty-one individuals (mean age, forty-four years) with thirty-nine Mason type-II, ten Mason type-III, and twelve Mason type-IV fractures were evaluated subjectively, objectively, and radiographically at a mean of eighteen years (range, eleven to thirty-three years) after treatment. Forty-three fractures were treated with primary radial head excision, and the remaining eighteen were treated with delayed radial head excision at a median of five months (range, one to 238 months) after the injury. RESULTS At the time of follow-up, twenty-eight individuals had no symptoms, twenty-seven had occasional elbow pain, and six had daily pain. Four individuals with daily pain had had a Mason type-IV fracture. The range of motion of the formerly injured upper extremities was slightly less than that of the uninjured upper extremities in terms of flexion (139 degrees +/- 11 degrees compared with 142 degrees +/- 8 degrees ), extension (-7 degrees +/- 12 degrees compared with -1 degrees +/- 6 degrees ), and supination (77 degrees +/- 20 degrees compared with 85 degrees +/- 10 degrees ) (all p < 0.01). A higher percentage of formerly injured elbows than uninjured elbows had cysts, sclerosis, and osteophytes (73% compared with 7%; p < 0.001), but none had a reduced joint space. No differences were found between the outcomes for individuals treated with a primary radial head excision and those for individuals treated with a delayed excision. CONCLUSIONS Following a displaced radial head or neck fracture, excision of the radial head often leads to a good or fair result. We found no differences in outcome between primary and delayed radial head excisions following a Mason type-II, III, or IV fracture. The outcomes are associated with the type of fracture, with Mason type-IV fractures having the worst results, rather than with the timing of the radial head excision (primary or delayed).
The serum S100B concentration is age dependent.

S100B is a 21-kDa calcium-binding protein produced and released primarily by astrocytes in the central nervous system (CNS), where it exerts neurotropic and gliotropic actions (1). Several studies have investigated the potential role of S100B as a peripheral biochemical marker of neural injury, including reactive gliosis, astrocytic death, and/or blood-brain barrier dysfunction (2). Increased cerebrospinal fluid (CSF) and/or serum S100B has been reported in several acute and chronic injuries, including traumatic brain injury (3), stroke (4), Alzheimer disease (5), schizophrenia (6), HTLV-I-associated myelopathy (7), and systemic lupus erythematosus (8). Previous neurodevelopmental studies have demonstrated age-related changes in S100B tissue expression and distribution in the CNS in mammals, which may be related to the different roles of this protein in distinct brain regions during the fetal period, adulthood, and aging (1)(9). Furthermore, S100B concentrations in CSF have been noted to increase with age in healthy individuals (10). Because these increases are more evident in men than women (11), S100B concentrations in CSF may be sex and age dependent, suggesting that age- and sex-matched controls may be necessary for studies of S100B in CSF. To determine the usual concentrations for plasma S100B in adults, Wiesmann et al. (12) measured the protein in healthy blood donors and found no differences with sex and age in individuals 18–65 years of age, in agreement with our findings in previous studies in adults (6)(7)(8). To our knowledge, however, S100B concentrations in blood in childhood and adolescence were not established until recently. The present study was performed to verify S100B serum concentrations in healthy individuals of different ages, ranging from neonates to adults. We collected blood samples from 19 healthy term neonates (<48 h of age) and from 25 healthy children 4–16 years of age undergoing routine clinical and …
The flow of digital labor

Digital microwork is a type of labor that many—typically poorly paid—workers engage in. In our research, we focus on an experience-based model of digital labor and the nonmonetary benefits derived from such activities. Based on a survey of 701 workers at Amazon Mechanical Turk, we demonstrate that experiences during digital labor sequences generate flow-like states of immersion. We show that reaching flow-like states while performing microwork depends on certain work characteristics, such as the particular worker’s degree of autonomy, the extent to which a worker’s skills are utilized, and the apparent significance of and feedback derived from the task. The results both highlight the importance of flow-like immersion in explaining why individuals engage in digital labor projects and point to avenues that can lead to the design of better digital work experiences.
Neurofibromatosis type 1 due to germ-line mosaicism in a clinically normal father.

BACKGROUND The mutation rate of the neurofibromatosis type 1 (NF1) gene is one of the highest in the human genome, with about 50 percent of cases being due to new mutations. We describe a family in which neurofibromatosis type 1 occurred in two siblings with clinically normal parents, and we demonstrate germ-line mosaicism in the father. METHODS We studied lymphocyte DNA from each member of the family and the father's spermatozoa for several polymorphic intragenic markers of the NF1 gene. Southern blots of DNA digested with several enzymes were hybridized with complementary DNA and individual NF1 exon probes to search for alterations in the gene. RESULTS The affected siblings, with a clinically severe form of neurofibromatosis type 1, showed no inheritance of paternal alleles for a marker in intron 38 of the NF1 gene, whereas they received alleles from both parents for other NF1 markers. Analysis with probes from this region of the NF1 gene showed a 12-kb deletion of the NF1 gene, involving exons 32 to 39, in the affected offspring. Ten percent of the father's spermatozoa carried the same NF1 deletion, but the abnormality was not detected in DNA from his lymphocytes. CONCLUSIONS The presence of the NF1 mutation in 10 percent of the clinically normal father's spermatozoa supports the hypothesis that most germ-line mutations occur in precursors of gametes. In cases of spontaneous mutation, analyzing the specific NF1 mutation in the father's sperm might help in the detection of mosaicism and thus facilitate genetic counseling about further pregnancies.
Oxygen-transfer strategy and its regulation effects in serine alkaline protease production by Bacillus licheniformis.

The effects of oxygen transfer on the production and product distribution in serine alkaline protease (SAP) fermentation by Bacillus licheniformis and oxygen-transfer strategy in relation to the physiology of the bacilli were investigated on a defined medium with citric acid as sole carbon source in 3.5-dm(3) batch bioreactor systems. By forming a 3 x 3 matrix with the parameters air-inlet rates of Q(O)/V(R) = 0.2, 0.5, 1.0 vvm, and agitation rates of N = 150, 500, 750 min(-1), the effects of oxygen transfer were investigated at nine different conditions. The concentrations of the product SAP and by-products, i.e., neutral protease, alpha-amylase, amino acids, and organic acids, and SAP activities were determined throughout the bioprocess. Among the constant air-flow and agitation-rate fermentations, Q(O)/V(R) = 0.5 vvm, N = 750 min(-1) oxygen-transfer conditions produced maximum SAP activity that was 500 U cm(-3), at t = 37 h. With the increase in Q(O)/V(R) and/or N, Damköhler number that is the oxygen-transfer limitation decreases; and the process passes from oxygen-transfer limited conditions to biochemical-reaction limited conditions. Further increase in SAP activity, A = 680 U cm(-3) was achieved by applying an oxygen-transfer strategy based on the analysis of the data obtained with the constant oxygen-transfer condition experiments, with a step increase in air-inlet rate, from Q(O)/V(R) = 0.2 to Q(O)/V(R) = 0.5 vvm at N = 750 min(-1) constant agitation rate at t = 24 h. Organic acids and amino acids that were excreted to the fermentation medium varied depending on the oxygen-transfer conditions. With the increase in oxygen-transfer rate acetic acid concentration increased; contrarily, with the decrease in the oxygen-transfer rate the TCA-cycle organic acids alpha-ketoglutaric and succinic acids, and gluconic acid were excreted to the fermentation broth; nevertheless, the application of the oxygen-transfer strategy prevented the increase in acetic acid concentration between t = 35-38 h. Under all the oxygen-transfer conditions, the amino acid having the highest concentration and the amino acid that was not excreted to the fermentation broth were lysine and asparagine, respectively; both of which belong to the aspartic acid-group amino acids. Further, this result indicates the requirement of the genetic regulation directed to the aspartic acid-group enzymes for the progress in SAP production in B. licheniformis.
Three-Month-Olds’ Brain Responses to Upright and Inverted Faces and Cars

We examined the processing of upright and inverted faces and cars in 3-month-old infants applying an event-related-potentials paradigm. The current study is the first to contrast human faces with an object category, cars, in a within-subjects design with infants. N290 amplitude was larger for inverted than upright faces, whereas no inversion effect was observed for cars. Moreover, N290 latency was enhanced for inverted faces and cars. This indicates that neural processing may already be partly face-specific in young infants.
Buried water molecules in helical transmembrane proteins

Buried water molecules (having no contact with bulk solvent) in 30 helical transmembrane (TM) protein structures were identified. The average amount of buried water in helical TM proteins is about the same as for all water‐soluble (WS) proteins, but it is greater than the average for helical WS proteins. Buried waters in TM proteins make more polar contacts, and are more frequently found contacting helices than in WS proteins. The distribution of the buried water binding sites across the membrane profile shows that the sites to some extent reflect protein function. There is also evidence for asymmetry of the sites, with more in the extracellular half of the membrane. Many of the buried water contact sites are conserved across families of proteins, including family members having different functions. This suggests that at least some buried waters play a role in structural stabilization. Disease‐causing mutations, which are known to result in misfolded TM proteins, occur at buried water contact sites at a higher than random frequency, which also supports a stabilizing role for buried water molecules.
Role of phosphate and calcium stores in muscle fatigue

Intensive activity of muscles causes a decline in performance, known as fatigue, that is thought to be caused by the effects of metabolic changes on either the contractile machinery or the activation processes. The concentration of inorganic phosphate (Pi) in the myoplasm ([Pi]myo) increases substantially during fatigue and affects both the myofibrillar proteins and the activation processes. It is known that a failure of sarcoplasmic reticulum (SR) Ca2+ release contributes to fatigue and in this review we consider how raised [Pi]myo contributes to this process. Initial evidence came from the observation that increasing [Pi]myo causes reduced SR Ca2+ release in both skinned and intact fibres. In fatigued muscles the store of releasable Ca2+ in the SR declines mirroring the decline in SR Ca2+ release. In muscle fibres with inoperative creatine kinase the rise of [Pi]myo is absent during fatigue and the failure of SR Ca2+ release is delayed. These results can all be explained if inorganic phosphate can move from the myoplasm into the SR during fatigue and cause precipitation of CaPi within the SR. The relevance of this mechanism in different types of fatigue in humans is considered.
Dna polymerase arrest by adducted trivalent chromium

Carcinogenic chromium (Cr6+) enters cells via the sulfate transport system and undergoes intracellular reduction to trivalent chromium, which strongly adducts to DNA. In this study, the effect of adducted trivalent chromium on in vitro DNA synthesis was analyzed with a polymerase‐arrest assay in which prematurely terminated replication products were separated on a DNA sequencing gel. A synthetic DNA replication template was treated with increasing concentrations of chromium(III) chloride. The two lowest chromium doses used resulted in biologically relevant adduct levels (6 and 21 adducts per 1,000 DNA nucleotides) comparable with those measured in nuclear matrix DNA from cells treated with a 50% cytotoxic dose of sodium chromate in vivo. In vitro replication of the chromium‐treated template DNA using the Sequenase version 2.0 T7 DNA polymerase (United States Biochemical Corp., Cleveland, OH) resulted in dose‐dependent polymerase arrest beginning at the lowest adduct levels analyzed. The pattern of polymerase arrest remained consistent as chromium adduct levels increased, with the most intense arrest sites occurring 1 base upstream of guanine residues on the template strand. Replication by the DNA polymerase I large (Klenow) fragment as well as by unmodified T7 DNA polymerase also resulted in similar chromium‐induced polymerase arrest. Interstrand crosslinking between complementary strands was detected in template DNA containing 62, 111, and 223 chromium adducts per 1,000 DNA nucleotides but not in template containing 6 or 21 adducts per 1,000 DNA nucleotides, in which arrest nevertheless did occur. Low‐level, dose‐dependent interstrand cross‐linking between primer and template DNA, however, was detectable even at the lowest chromium dose analyzed. Since only 9% of chromium adducts resulted in polymerase arrest in this system, we hypothesized that arrest occurred when the enzyme encountered chromium‐mediated interstrand DNA‐DNA cross‐links between either the template and a separate DNA molecule or the template and its complementary strand in the same molecule. These results suggest that the obstruction of DNA replication by chromium‐mediated DNA‐DNA cross‐links is a potential mechanism of chromium‐induced genotoxicity in vivo. © 1994 Wiley‐Liss, Inc.
Multistep Level Sections to Detect Occult Fallopian Tube Carcinoma in Risk-reducing Salpingo-oophorectomies From Women With BRCA Mutations: Implications for Defining an Optimal Specimen Dissection Protocol

Risk-reducing salpingo-oophorectomy (RRSO) significantly lowers the incidence of ovarian, tubal, peritoneal, and breast cancer in women who carry BRCA1 or BRCA2 germline mutations. A minority of RRSO specimens from these women will contain occult early-stage carcinoma. Most occult cancer is localized in the fallopian tube fimbriae and is as small as 1 mm in size. Pathologic detection is dependent on thoroughness of tissue examination. Recommended protocols to maximize tumor detection emphasize the role of thinly slicing the tubes and ovaries and embedding the entire specimen for microscopic examination. Additional multistep level sections of tubal fimbriae tissue blocks could theoretically increase detection of occult tubal carcinoma but the value of level sections has not been formally evaluated. This study tests the diagnostic utility of multistep level sections in RRSO specimens from 102 women with BRCA germline mutations. The original diagnoses were based on a single section from each block of thinly sliced (2 to 3 mm intervals) tissues of the entire RRSO specimen. Three multistep level sections were retrospectively obtained from each block containing tubal fimbriae. Clinically occult carcinoma ranging in size from 1 to 13 mm was initially detected in 11 of 102 women (5 in tubal fimbriae only, 1 in tubal isthmus only, 2 in fimbriae and ovary, and 3 in ovary only). Diagnoses in the original fimbrial slides and their level sections were concordant in all cases. All tubal cancers were detected in both the original sections and in the multistep level sections. None of the tubal carcinomas that were noninvasive on the original slides showed invasive growth on additional level sections. No tubal carcinoma was identified in the level sections of any case originally classified as benign. Clinical follow-up among women with benign RRSO findings revealed that 2 women subsequently developed peritoneal carcinomatosis at 22 and 62 months postoperatively. Retrospective exhaustive multistep level sectioning of all remaining tubal and ovarian blocks from both these women confirmed the original benign diagnosis in 1 woman but in the other woman, the deepest levels of 1 ovarian block revealed a single 1-mm nodule of cancer at the base of an ovarian surface epithelial invagination. This specimen was one of the first RRSO cases in our experience and on review of the original report, this ovary was not dissected into multiple slices along its short axis but was only bivalved along its long axis. We propose that there does not seem to be any diagnostic value in automatically performing multistep deeper level sections of RRSO specimens if the tissue is sectioned appropriately and if the specimen is sliced at intervals that are no more than 3 mm thick. Guidelines for evaluation of RRSO specimens should emphasize the use of an optimal dissection protocol and the importance of thin tissue slice intervals.
Point Shear Wave Elastography in Assessment of Hepatic Fibrosis: Diagnostic Accuracy in Subjects With Native and Transplanted Livers Referred for Percutaneous Biopsy

Abstract The objective of this study was to prospectively evaluate the use of point shear wave elastography for the assessment of liver fibrosis and to determine the usefulness and optimal location for obtaining elastography measurements in native and transplanted livers. Point shear wave elastography measurements were obtained from 100 consecutive patients presenting for percutaneous liver biopsy. Measurements were acquired within both the superior right hepatic lobe (segments VII/VIII) via an intercostal approach and the inferior right hepatic lobe (segments V/VI) via a subcostal approach. Analysis of variance was used to assess statistical differences between the degree of fibrosis on percutaneous liver biopsy and elastography measurements. No statistical difference was present when comparing elastography measurements in patients with hepatic steatosis compared with patients without steatosis (P = 0.2759). There was no difference in the accuracy of elastography measurements in native livers versus transplanted livers (P = 0.221). Point shear wave elastography can accurately differentiate between patients with no-to-mild hepatic fibrosis (F0–F1) and moderate-to-severe hepatic fibrosis (≥F2) with sensitivity of 72% and specificity of 69%. Point shear wave elastography can be used as a noninvasive method to assess fibrosis in patients with native or transplanted livers. In addition, measurements can be combined or taken separately from either the superior or inferior right hepatic lobe. The presence of hepatic steatosis does not affect the accuracy of point shear wave elastography. However, shear wave elastography values in patients with body mass index greater than 40 should be interpreted with caution.