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Sexual selection often favours investment in expensive sexual traits that help individuals compete for mates. In a rapidly changing environment, however, allocation of resources to traits related to reproduction at the expense of those related to survival may elevate extinction risk. Empirical testing of this hypothesis in the fossil record, where extinction can be directly documented, is largely lacking. The rich fossil record of cytheroid ostracods offers a unique study system in this context: the male shell is systematically more elongate than that of females, and thus the sexes can be distinguished, even in fossils. Using mixture models to identify sex clusters from size and shape variables derived from the digitized valve outlines of adult ostracods, we estimated sexual dimorphism in ostracod species before and after the Cretaceous/Palaeogene mass extinction in the United States Coastal Plain. Across this boundary, we document a substantial shift in sexual dimorphism, driven largely by a pronounced decline in the taxa with dimorphism indicating both very high and very low male investment. The shift away from high male investment, which arises largely from evolutionary changes within genera that persist through the extinction, parallels extinction selectivity previously documented during the Late Cretaceous under a background extinction regime. Our results suggest that sexual selection and the allocation of resources towards survival versus reproduction may be an important factor for species extinction during both background and mass extinctions. [ABSTRACT FROM AUTHOR]

The endangered Hawaiian Coot (Fulica alai) is one of few native waterbird species remaining in Hawaii, USA. On the island of Oahu, 56 adults were captured and sexed using a molecular method, and sexual dimorphism, seasonal variation in shield size (possibly sexually selected), and use of morphometrics to predict sex as an alternative to molecular sexing were investigated. The sex ratio was significantly male biased: 39 males, 17 females (P = 0.003). No morphometric character assessed independently differed significantly between sexes (0.056 < P < 0.975). However, a multiple regression approach indicated that tarsus length, bill height, tail length, and wing length in combination differed between sexes, but prediction of sex was nonetheless possible with only 65% accuracy. Male shield size was larger during the pre-breeding and breeding seasons than the post-breeding season, but did not vary significantly in females, the interaction between sex and season in the model being significant (P < 0.02). Within the breeding and pre-breeding seasons (a subsample of total birds), multiple regression indicated sexual dimorphism in shield width, shield length, and wing length, but prediction of sex was again only possible with 68% accuracy. Thus, neither model predicted sex sufficiently accurately for this morphometric approach to be a viable substitute for molecular sexing. [ABSTRACT FROM AUTHOR]

Sexual dimorphism of visceral pain has been documented in clinics and experimental animal models. Aside from hormones, emerging evidence suggests the sex-differential intrinsic neural regulation of pain generation and maintenance. According to the International Association for the Study of Pain (IASP) and the American College of Gastroenterology (ACG), up to 25% of the population have visceral pain at any one time, and in the United States 10–15 percent of adults suffer from irritable bowel syndrome (IBS). Here we examine the preclinical and clinical evidence of sex differences in visceral pain focusing on IBS, other forms of bowel dysfunction and IBS-associated comorbidities. We summarize preclinical animal models that provide a means to investigate the underlying molecular mechanisms in the sexual dimorphism of visceral pain. Neurons and nonneuronal cells (glia and immune cells) in the peripheral and central nervous systems, and the communication of gut microbiota and neural systems all contribute to sex-dependent nociception and nociplasticity in visceral painful signal processing. Emotion is another factor in pain perception and appears to have sexual dimorphism. [ABSTRACT FROM AUTHOR]

The weevil Rhyssomatus nigerrimus Fahraeus is a pest that feeds on pods and plants of soybeans in Northwestern and Southeast Mexico. It is important to determine sexually dimorphic characters of R. nigerrimus for rapid separation of sexes for bioecology, behavior, and control studies. The objective of this work was to determine the sexual dimorphism and ratio of R. nigerrimus adults. The sexual proportion between males and females was approximately 1:1. We concluded that it is possible to separate adults of R. nigerrimus by sex based on secondary sexual characters, especially the mucro on the protibia. [ABSTRACT FROM AUTHOR]

We investigated molar-crown-size variation, sexual dimorphism, and allometry in the black bear (Ursus americanus), using hunter-shot specimens (n = 429) from the island of Newfoundland, and museum specimens from elsewhere in Canada and the continental United States (n = 502). We predicted higher variation in and weaker correlations among molar size in this omnivorous species than in other species of Carnivora with dentition more specialized for carnivory, because of relatively weak normalizing selection on food-processing mechanisms in U. americanus. Molar-size variation in Newfoundland bears (mean coefficient of variation ~ 5.6%) was intermediate between species of Carnivora with simpler (e.g., pinnipeds) and more complex (e.g., canids) postcanine dentition. There was negligible size variation within the molar teeth, unlike some mammals. Bilateral symmetry was strong, especially in mandibular length (r ~ 1.0 between left and right sides; r ~ 0.95 for other mandibular and maxillary variables and molar size); symmetry in molar size was higher than in phocid seals. Size was positively correlated across molars, especially between adjacent (but not occluding) molars; patterns were similar between sexes and geographic regions, and correlation levels did not differ from other species of Carnivora. We also predicted (and found) smaller sexual differences (= 100[(male/female) - 1]) in molar size than in body size, because definitive molar size is attained early in life: differences in molar size averaged ~5.5% in Newfoundland (higher in continental subsamples), which is less than differences in cranial size (7-9%) or body mass1/3 (21%). Sexes did not differ in relative molar size. Molar size was mainly isometric or positively allometric to adult body size (using mandibular and maxillary size as proxies). [ABSTRACT FROM AUTHOR]

Digit length ratios are organized during embryonic development and may show sexual dimorphism related to steroid exposure. The second-to-fourth digit length ratio (2D:4D) has received the most attention. In the present study, we measured 2D:4D of all four feet of adult male and female green anoles (Anolis carolinensis Voigt, 1832) to determine whether it is sexually dimorphic and whether results are repeatable across laboratories. Lizards were housed at Michigan State University (MSU) and Oklahoma State University (OSU), and one investigator at each institution used digital calipers to measure the 2D:4D of each foot. At both MSU and OSU, we found that males had a significantly larger 2D:4D on the back right foot than females did, and that no sex difference existed in either the back left or the front right foot. Furthermore, although no sex difference in the front left foot was found at MSU, the 2D:4D on this foot was larger in females at OSU. Our results demonstrate both sexual dimorphism in 2D:4D and repeatability between laboratories, but they also suggest the importance of verifying such repeatability if 2D:4D or any other digit length ratio is used as a potential indicator of the early steroid environment. [ABSTRACT FROM AUTHOR]

Qualitative methods of describing sexual dimorphism in discrete cranial traits have been criticized for their subjectivity and statistical limitations. However, researchers have yet to be able to accurately capture the morphology of these individual traits using traditional metric techniques. This article presents a method to quantify morphological variation in the skeletal browridge and chin using 3D surface laser scans. Browridge and chin regions are isolated from the skull using objectively defined landmarks and planes. Region areas and volumes are used to quantify absolute and relative size, while semilandmarks along transects are used for more detailed morphometric analyses. An intraobserver error study indicates high repeatability of the method. Application of the method is demonstrated on a sample of US males and females of black and white ancestries. Results suggest significant effects of both sex and ancestry on brow and chin morphologies and are consistent with traditional qualitative descriptions. Our results indicate that the method can accurately and reliably quantify browridge and chin morphologies, providing a tool to objectively describe and statistically analyze these traditionally qualitative discrete cranial traits. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Kennethia pomorskii, a new genus and species of subfamily Onychiurinae is described from North America. It has a unique suite of apomorphic morphological characters and is most closely related to Arneria Pomorski, 2000; Dinochiurus Pomorski & Steinmann, 2004; and Reducturus Pomorski & Steinmann 2004. A key to genera of the tribe Hymenaphorurini is given. [ABSTRACT FROM AUTHOR]

Tetragnathid spiders (Tetragnatha spp.) found in riparian habitats have recently been used as bioindicators of sediment contamination and insect-mediated contaminant flux. We investigated whether sexual dimorphism (size and behavior) influenced the female:male ratio in composite samples, stable isotope ratios (carbon [δ 13 C], nitrogen [δ 15 N]), and Hg concentrations in the southern United States. Additionally, we explored whether biomass for contaminant analysis could be preserved by using the legs of tetragnathids as a surrogate for whole-body δ 13 C and δ 15 N signatures. We found that female tetragnathids were significantly larger than male spiders and represented a larger proportion of spiders collected at all sites. However, despite the difference in size between sexes, no differences in growth dynamics, isotopic signatures (δ 13 C and δ 15 N), or mercury concentrations were observed. It was determined that the leg of a tetragnathid can accurately represent the stable isotope signature of an entire spider.

Background: Sex differences in the incidences of cancers become a critical issue in both cancer research and the development of precision medicine. However, details in these differences have not been well reported. We provide a comprehensive analysis of sexual dimorphism in human cancers., Methods: We analyzed four sets of cancer incidence data from the SEER (USA, 1975-2015), from the Cancer Registry at Mayo Clinic (1970-2015), from Sweden (1970-2015), and from the World Cancer Report in 2012., Results: We found that all human cancers had statistically significant sexual dimorphism with male dominance in the United States and mostly significant in the Mayo Clinic, Sweden, and the world data, except for thyroid cancer, which is female-dominant., Conclusions: Sexual dimorphism is a clear but mostly neglected phenotype for most human cancers regarding the clinical practice of cancer. We expect that our study will facilitate the mechanistic studies of sexual dimorphism in human cancers. We believe that fully addressing the mechanisms of sexual dimorphism in human cancers will greatly benefit current development of individualized precision medicine beginning from the sex-specific diagnosis, prognosis, and treatment.

Sexual size dimorphism is common in many taxa and results from various pressures, including competition, reproductive requirements, functional differences, and sexual recognition. For mammals, males are typically the larger sex; however, for vespertilionid bats, females are more often the larger sex. Forearm length, a feature that influences overall wing and body size and is often sexually dimorphic, is a standard morphological measurement taken from bats. Forearm length was measured in two vesper bat species (Corynorhinus rafinesquii and Myotis austroriparius) that co-occur across much of the southeastern United States. Forearm length was greater in females of both species, and females of both species also exhibited regional variation in forearm length. By having a longer forearm and therefore being larger in size, females may be more maneuverable and better equipped to carry young. While this study did not directly investigate the mechanisms behind regional variation in forearm length, it is possible this is the result of variability in habitat types, resources, or thermodynamic constraints. Knowledge of sexually dimorphic characteristics is important for obtaining a general understanding of a species and its morphology. [ABSTRACT FROM AUTHOR]

Autoimmune diseases occur when the immune system attacks and destroys the organs and tissues of its own host. Autoimmunity is the third most common type of disease in the United States. Because there is no cure for autoimmunity, it is extremely important to study the mechanisms that trigger these diseases. Most autoimmune diseases predominantly affect females, indicating a strong sex bias. Various factors, including sex hormones, the presence or absence of a second X chromosome, and sex-specific gut microbiota can influence gene expression in a sex-specific way. These changes in gene expression may, in turn, lead to susceptibility or protection from autoimmunity, creating a sex bias for autoimmune diseases. In this Review we discuss recent findings in the field of sex-dependent regulation of gene expression and autoimmunity.

Conclusive evidence for sexual dimorphism in non-avian dinosaurs has been elusive. Here it is shown that dimorphism in the shape of the dermal plates of Stegosaurus mjosi (Upper Jurassic, western USA) does not result from non-sex-related individual, interspecific, or ontogenetic variation and is most likely a sexually dimorphic feature. One morph possessed wide, oval plates 45% larger in surface area than the tall, narrow plates of the other morph. Intermediate morphologies are lacking as principal component analysis supports marked size- and shape-based dimorphism. In contrast, many non-sex-related individual variations are expected to show intermediate morphologies. Taphonomy of a new quarry in Montana (JRDI 5ES Quarry) shows that at least five individuals were buried in a single horizon and were not brought together by water or scavenger transportation. This new site demonstrates co-existence, and possibly suggests sociality, between two morphs that only show dimorphism in their plates. Without evidence for niche partitioning, it is unlikely that the two morphs represent different species. Histology of the new specimens in combination with studies on previous specimens indicates that both morphs occur in fully-grown individuals. Therefore, the dimorphism is not a result of ontogenetic change. Furthermore, the two morphs of plates do not simply come from different positions on the back of a single individual. Plates from all positions on the body can be classified as one of the two morphs, and previously discovered, isolated specimens possess only one morph of plates. Based on the seemingly display-oriented morphology of plates, female mate choice was likely the driving evolutionary mechanism rather than male-male competition. Dinosaur ornamentation possibly served similar functions to the ornamentation of modern species. Comparisons to ornamentation involved in sexual selection of extant species, such as the horns of bovids, may be appropriate in predicting the function of some dinosaur ornamentation.

One of the four pillars of the anthropological protocol is the estimation of sex. The protocol generally consists of linear metric analysis or visually assessing individual skeletal traits on the skull and pelvis based on an ordinal scale of 1–5, ranging from very masculine to very feminine. The morphologic traits are then some how averaged by the investigator to estimate sex. Some skulls may be misclassified because of apparent morphologic features that appear more or less robust due to size differences among individuals. The question of misclassification may be further exemplified in light of comparisons across populations that may differ not only in cranial robusticity but also in stature and general physique. The purpose of this study is to further examine the effect of size and sex on craniofacial shape among American populations to better understand the allometric foundation of skeletal traits currently used for sex estimation. Three-dimensional coordinates of 16 standard craniofacial landmarks were collected using a Microscribe-3DX digitizer. Data were collected for 118 American White and Black males and females from the W.M. Bass Donated Collection and the Forensic Data Bank. The MANCOVA procedure tested shape differences as a function of sex and size. Sex had a significant influence on shape for both American Whites ( F = 2.90; d.f. = 19, 39; p > F = 0.0024) and Blacks ( F = 2.81; d.f. = 19, 37; p > F = 0.0035), whereas size did not have a significant influence on shape in either Whites ( F = 1.69; d.f. = 19, 39; p > F = 0.08) or Blacks ( F = 1.09; d.f. = 19, 37; p > F = 0.40). Therefore, for each sex, individuals of various sizes were statistically the same shape. In other words, while significant differences were present between the size of males and females (males on average were larger), there was no size effect beyond that accounted for by sex differences in size. Moreover, the consistency between American groups is interesting as it suggests that population differences in sexual dimorphism may result more from human variation in size than allometric variation in craniofacial morphology. [ABSTRACT FROM AUTHOR]

Historical dynamics of age-related mortality of men and women in Finland, Sweden, Netherlands, Denmark, England, France, Italy, Japan, Norway, Spain, Switzerland, USA is studied. Men's over-mortality is shown to undergo regular changes in the course of time. A common regularity is found in all the studied countries within the last 50 years: a significant increase of men's over-mortality with a following decrease. A slight change of approximation limits while calculating parameters of the Gompertz equation is shown to be able to result in qualitative changes in dynamics of the parameters, and hence has an influence on the Strehler-Mildvan correlation.

Background: The preponderance of existing results suggests that, relative to stature, women have smaller feet than men. However, several investigations indicate that the relationship between foot length and stature may be curvilinear, a pattern that, due to the dimorphic nature of stature, would mask the true direction of pedal sexual dimorphism in published results., Aim: The study aimed to determine whether proportionate foot length is sexually dimorphic and, if so, the nature of that dimorphism., Materials and Methods: Surveying genetically disparate populations (USA, Turkey, and Native North and Central American), we examined data from three previous anthropometric studies (Davis 1990, Parham et al. 1992, Ozaslan et al. 2003) and foot tracings from the Steggerda Collection at the US National Museum of Health and Medicine. Analyses explored sex differences in the ratio between foot length and stature, and tested for nonlinearity., Results: Although varying in degree across populations, proportionate to stature, female foot length is consistently smaller than male foot length., Conclusion: Given the biomechanical challenges posed by pregnancy, smaller female proportionate foot length is somewhat surprising, as foot length affects dorsoventral stability. It is possible that the observed pattern reflects intersexual selection for small female foot size, a cue of youth and nulliparity.

Patterns of genetic variation and covariation strongly affect the rate and direction of evolutionary change by limiting the amount and form of genetic variation available to natural selection. We studied evolution of morphological variance-covariance structure among seven populations of house finches (Carpodacus mexicanus) with a known phylogenetic history. We examined the relationship between within- and among-population covariance structure and, in particular, tested the concordance between hierarchical changes in morphological variance-covariance structure and phylogenetic history of this species. We found that among-population morphological divergence in either males or females did not follow the within-population covariance patterns. Hierarchical patterns of similarity in morphological covariance matrices were not congruent with a priori defined historical pattern of population divergence. Both of these results point to the lack of proportionality in morphological covariance structure of finch populations, suggesting that random drift alone is unlikely to account for observed divergence. Furthermore, drift alone cannot explain the sex differences in within- and among-population covariance patterns or sex-specific patterns of evolution of covariance structure. Our results suggest that extensive among-population variation in sexual dimorphism in morphological covariance structure was produced by population differences in local selection pressures acting on each sex.

Objectives: To review the literature and summarize the evidence of temporomandibualar joint (TMJ) disorders (TMDs) in older adults, focusing on clinical manifestations of TMDs in older adults, highlighting the incidence and sexual dimorphism of TMJ degeneration and the role of sex hormones in this process, and providing potential treatment options for TMD in older adults. Design: Two review authors performed the literature search, study inclusion, and data extraction. PubMed, Embase, and Google scholar were searched for literature until August 2017 (Figure ). We adopted a combination of Medical Subject Headings with related free text words for the search in PubMed and optimized the search in other search engines. Results: Traditionally, it was believed that TMDs predominantly affected women of childbearing age, but recent large studies in Europe and the United States have shown that the prevalence of TMD peaks after childbearing age (45–64) and then gradually decreases with age, although not much is known about the disease in older adults. Conclusion: Most older adults have TMJ degeneration, which affects women more than men. In most older adults, the symptoms of TMD are mild and self‐limiting and can usually be treated with self management. [ABSTRACT FROM AUTHOR]

This study tests for differences in articular and diaphyseal size and shape of the distal femur and proximal tibia between normal weight and obese individuals, and discusses the effects of obesity on the patterns of sexual dimorphism and secular change in the skeletal morphology of the knee. Measurements of the femur and tibia were recorded for 143 American White adult males and females born in the 20th century. The sample was divided into normal and obese weight categories based on the body mass index. Results show differences between normal weight and obese individuals in the size and shape of the femoral shaft and the medial side of the knee joint, none of which affect the pattern of sexual dimorphism. While changes in skeletal morphology associated with obesity may be observed in recent secular changes, its role is still unclear because of the relatively recent increase in obesity prevalence. [ABSTRACT FROM AUTHOR]

Examination of 36 specimens of the Pennsylvanian horseshoe crab Euproops danae (Meek & Worthen, 1865) from a previously unreported occurrence in the lower Mercer Shale exposed in an abandoned strip mine south from Windber, Pennsylvania, USA, document ontogenetic changes in prosomal morphology. Intercardiophthalmic transverse bars become less pronounced as ophthalmic spines become longer in larger, older specimens through approximately seven instar stages. It remains unclear if the presence or absence of ophthalmic spines is taphonomic, regardless of developmental stage. The holotype of E. danae is illustrated photographically for the first time. [ABSTRACT FROM AUTHOR]

Background: Latinos have the lowest leisure-time physical activity (LTPA) rates. However, measurement of only LTPA might underestimate total physical activity. This study compares the objective physical activity of Latinos reporting high or low levels of LTPA and also compares gender differences. Methods: Data were obtained from 148 Latinos (n = 83 women, n = 65 men). Freedson cut points were employed to determine daily minutes of activity. Results: Latinos reporting high LTPA engaged in more daily minutes of vigorous and very vigorous activity than Latinos reporting low LTPA (P values < .05). There was no difference in daily minutes of moderate-intensity activity (P = .12), with both groups of Latinos meeting Centers for Disease Control and Prevention/American College of Sports Medicine guidelines. Men engaged in more daily minutes of moderate activity than women (P < .01). Conclusions: Many Latinos met physical activity guidelines even when reporting low levels of LTPA. Future studies should determine whether equivalent health benefits are achieved by meeting guidelines through LTPA and non-LTPA. [ABSTRACT FROM AUTHOR]

Transgender and gender-diverse (TGD) individuals in the United States face health care disparities compounded with discrimination and limited access to necessary medical services. Gender-affirming interventions have been shown to mitigate gender dysphoria and psychiatric comorbidities, yet United States legislation limiting such interventions has increased. As medication experts, pharmacists can facilitate access to care and appropriate use of gender-affirming hormone therapy (GAHT) and educate other health care providers on best practices for caring for TGD individuals in a variety of settings. To provide pharmacists with a contemporary review of GAHT and associated medication-related concerns. We searched PubMed for articles published until December 2022. MeSH terms such as transgender, transsexual, gender diverse, gender variant, or gender nonconforming in combination with phrases like gender-affirming care, treatment, pharmacotherapy, or hormone therapy were used to capture desired articles. Feminizing hormone therapy (FHT), such as estrogen and antiandrogen agents, increases female secondary sex characteristics while suppressing male secondary sex characteristics. Masculinizing hormone therapy (MHT) achieves male secondary sex characteristics and minimizes female secondary sex characteristics using testosterone. For both FHT and MHT, the choice of therapy and formulation ultimately involves the patient's treatment goals, preferences, and tolerability. GAHT has additional health considerations pertaining to renal drug dosing, fertility, cardiovascular, and cancer risks. Pharmacists may provide crucial guidance and education to both patients and health care providers regarding risks associated with GAHT. Many pharmacists feel unprepared to help provide, manage, and optimize GAHT. For many TGD individuals, GAHT is medically necessary and a life-saving treatment. Therefore, pharmacists should be provided tools to close knowledge gaps and improve their ability to care for these patients. By offering a thorough updated overview of GAHT, pharmacists can gain confidence to provide appropriate care for this increasingly visible population. [ABSTRACT FROM AUTHOR]

Abstract: Although the Nutrition Facts label has been a requirement on food packages for more than 20 years, few studies have conducted comprehensive assessments of food label use. The purpose of this study was to assess the demographic and psychosocial correlates of food label use using a comprehensive approach. A sample of 1,382 males and females (n=573 and n=809, respectively) aged 19 to 70 years was drawn from the 2005-2006 National Health and Nutrition Examination Survey. The food label Check and Use subscales are the sums of multiple questions on frequency of checking and using each separate component on a Nutrition Facts label. Multiple linear regression was used to assess differences in predictors of Check and Use. Determinants of food label use differed by sex. Women check and use food label components more often and thoroughly than men. Older adults and adults with good diet-quality perception were significant predictors of food label use for both men and women. Race was a significant predictor for men only. Mexican-American and other Hispanic groups check (P=0.03) and use (P=0.01) the food label more frequently than non-Hispanic white men. Men who do not receive Supplemental Nutrition Assistance Program benefits also check (P<0.01) and use (P=0.01) food labels more frequently than those who receive assistance. The findings of this study could be used to improve nutrition education efforts. It may be beneficial to target men and women separately, as food label use determinants are different. [Copyright &y& Elsevier]

This article summarizes the four articles in the Social Development quartet focused on positive affect regulation in youth. Each article in the quartet shows that parents' socialization of youth positive affect (e.g., encouraging, enhancing, savoring, or dampening responses) is associated with youth positive affect regulation and depressive symptoms. Further, three of the studies provide novel evidence for an indirect relationship whereby parental socialization predicts youth depressive symptoms through youth positive affect regulation. The studies include samples of youth across mid‐childhood and adolescence (7–18‐year‐olds) from three countries (the United States, Belgium, and India), and utilize several methods of assessing youth positive affect regulation or parental socialization (parent‐reported surveys, youth‐reported surveys, coded parent–child discussions). This integrative article also identifies several ways in which the study of youth positive affect regulation can be advanced. We address the conceptualization of positive affect regulation and the socialization of children's positive affect, constraints on the adaptiveness of upregulating positive emotions, methodological directions, potential moderated effects based on child characteristics such as sex or temperament, and the importance of studying outcomes beyond depression. [ABSTRACT FROM AUTHOR]

Evidence for sexual size dimorphism (SSD) and its possible causes were examined in the endangered Colorado pikeminnow Ptychocheilus lucius, a large, piscivorous, cyprinid endemic to the Colorado River system of North America. Individuals representing 18–24% of the upper Colorado River population were captured, measured, sexed and released in 1999 and 2000. Differing male and female total length-( LT) frequency distributions revealed SSD with females having greater mean and maximum sizes than males. Although both sexes exhibit indeterminate post-maturity growth, growth trajectories differed. The point of trajectory divergence was not established, but slowed male growth might coincide with the onset of maturation. Differing growth rate was the dominant proximate cause of SSD, accounting for an estimated 61% of the observed difference in mean adult LT. The degree of SSD in adults, however, was also related to two other factors. Evidence suggests males become sexually active at a smaller size and earlier age than females; a 2 year difference, suggested here, accounted for an estimated 12% of the between-sex difference in mean adult LT. Temporal shifts in gender-specific survival accounted for an additional 27% of the observed between-sex difference in mean adult LT. Estimated age distributions indicated a higher number of older females than older males and more younger males than younger females in the population during the period of sampling. Dissimilarity of age distributions was an unexpected result because the male : female population sex ratio was 1 : 1 and estimates of long-term annual survival for adult males and females were equal (88%). Future assessments of SSD in this population are apt to vary depending on the prior history of short-term gender-specific survival. Without recognizing SSD, non-gender-specific growth curves overestimate mean age of adult females and underestimate mean age of adult males of given LT. Assuming age 8 years for first reproduction in males and age 10 years for females, the adult male : female ratio was estimated as 1·1 : 1 and mean adult age, or generation time, was estimated as 16·4 years for males and 18·4 years for females. [ABSTRACT FROM AUTHOR]

Stygobromus flagellatus (Benedict, 1896) (Amphipoda, Crangonyctidae) is known from spring systems in Hays, Comal and Travis counties, Texas, USA. Routine censuses of community holding tanks revealed deviations in the number of lateral telson spines of females and males as given in the most recent description of the species. Other discrepancies included "double spines" and varying configurations of lateral telson spines in both females and males, including one female and one male that did not have any trace of lateral telson spines. Explanations for these deviations are discussed. [ABSTRACT FROM AUTHOR]

The article discusses U.S. constitutional sex discrimination law and the various tests employed by the U.S. Supreme Court when deciding sex discrimination cases, particularly focusing on the concept of inherent differences between males and females. The article discusses the cases United States v Virginia, Pavan v Smith, and Obergefell v Hodges. It also examines the significance of the case Sessions v Morales-Santana

The ostracode genus Fossocytheridea Swain and Brown 1964 is emended herein. A summary of the diagnostic characters include: (1) a median sulcus, (2) a tripartite antimerodont hinge with distinct heart-shaped terminal elements, (3) distinct sexual dimorphism; (4) a narrow inner margin that has 20-28 straight radial pore canals, and (5) variability in the external carapace (pore shape, pore density, and patterns of reticulation) that bears close resemblance to Cyprideis. Two new species are described from southwest Utah (U.S.A): Fossocytheridea mosbyense sp. nov. and Fossocytheridea kirklandi sp. nov. and 21 taxa previously assigned to Fabanella, Sarlatina, Ovocytheridea, Dolocytheridea, Antibythocypris, and Cytheridea are assigned to the emended genus. Fossocytheridea resembles Cyprideis with respect to both shell morphology and ecology since it occurs in association with euryhaline biota in coal-bearing strata. Expansion of marginal marine environments during the highest sea level of the Mesozoic saw Fossocytheridea successfully migrate and dominate restricted coastal environments. Since this expansion, the prominent characters of Fossocytheridea have been preserved in descendent genera belonging to the tribe Cyprideidini Kollmann 1960 that are preserved to this day in Cyprideis. [ABSTRACT FROM AUTHOR]

C-reactive protein (CRP) is a risk factor for cardiovascular disease and mortality; it is known to be positively associated with obesity but there is some evidence that this association differs by race or sex. We used nationally representative data of adults aged >50 years to investigate sex and race modifiers of the associations between obesity and CRP in non-Hispanic White males (n=3,517) and females (n=4,658), and non-Hispanic Black males (n=464) and females (n=826). Using multiple linear regression models with the natural logarithm of CRP as the dependent variable, we sequentially included body mass index (BMI), a body shape index (ABSI), and socioeconomic, health and health behavior covariates in the model. The association between BMI and CRP was significantly stronger in females than males. Obese White females had mean CRP values slightly above 3 mg/liter (vs 2 for White males) and Black females had mean CRP values >4 mg/liter (vs 3 for Black males). More than 50% of Black females in the United States have obesity. Continued research into racial and sex differences in the relationship between obesity, inflammation, and health risks may ultimately lead to more personalized weight loss recommendations. [ABSTRACT FROM AUTHOR]

Roehler's Coryphodon Catastrophe Quarry (Wasatch Formation, lower Eocene) in the Washakie Basin, Wyoming is a paucispecific assemblage containing a minimum of 10 individuals from a single population of cf. Coryphodon anthracoideus. The RCCQ Coryphodon assemblage provides a relatively rare opportunity to assess intraspecific variation in a genus that has historically been difficult to classify due to variation from specimen to specimen and species to species. Variation in metric features of the dentition (i.e., length, width, and molar area) in the RCCQ Coryphodon is within the range observed in comparable sexually dimorphic extant species. The RCCQ Coryphodon assemblage is also compared to another paucispecific, single population assemblage of Coryphodon molestus from New Mexico. Intraspecific metric variation characterizing these two assemblages is also comparable. In both assemblages, overall intraspecific metric variation is most pronounced in the third molar, suggesting sexual dimorphism as the source of variation. [ABSTRACT FROM AUTHOR]

The article focuses on the Office of Research on Women's Health (ORWH) of National Institute of Health (NIH). It states that ORWH has guided the national effort of NIH on the health of women and sex difference research. It mentions that ORWH aims to make sure that the research conducted and supported by NIH should deal with the issues about women's health. It adds that the study in women's health across the lifespan that requires an interdisciplinary approach to research was recognized by ORWH.

The article focuses on the significance of interactive scientific and public partnership in the attainment of the vision for 2020 research agenda on women's health of National Institutes of Health's (NIH's) Office of Research on Women's Health (ORWH). It states that the ORWH releases a revised research agenda on women's health that offers an outlook for scientific exploration that aims to increase advances in women's health and sex differences research. It mentions that one of the tasks of ORWH is to interact with the scientific and medical communities, organizations and other parts of government that concern in women's health. It says that ORWH conducts several meetings wherein participants contribute their ideas and suggestions for the research agenda.

The association between sexual debut timing and depressive symptomatology in adolescence and emerging adulthood was examined using data from Waves I, II and III of the National Longitudinal Study of Adolescent Health. Respondents who reported never having sexual intercourse at Wave I and were 18–22 years of age at Wave III were included ( n = 5,061). Twenty percent of respondents experienced early (

A content analysis of prime-time programming on the six US broadcast networks revealed unexpected differences between scripted programs and reality programs. Past research posited and found that women working in powerful behind-the-scenes roles are associated with greater on-screen representation of female characters and more egalitarian portrayals of conflict and its resolution. Although our hypotheses were confirmed for scripted programs, the presence of women behind the scenes on reality programs was negatively related to on-screen representation. Further, women behind the scenes on reality programs were less effective at eliminating gender differences in the portrayal of conflict resolution. [ABSTRACT FROM AUTHOR]

Moderate-to-heavy episodic ("binge") drinking is the most common form of alcohol consumption in the United States. Alcohol at binge drinking concentrations reduces brain artery diameter in vivo and in vitro in many species including rats, mice, and humans. Despite the critical role played by brain vessels in maintaining neuronal function, there is a shortage of methodologies to simultaneously assess neuron and blood vessel function in deep brain regions. Here, we investigate cerebrovascular responses to ethanol by choosing a deep brain region that is implicated in alcohol disruption of brain function, the hippocampal CA1, and describe the process for obtaining simultaneous imaging of pyramidal neuron activity and diameter of nearby microvessels in freely moving mice via a dualcolor miniscope. Recordings of neurovascular events were performed upon intraperitoneal injection of saline versus 3 g/kg ethanol in the same mouse. In male mice, ethanol mildly increased the amplitude of calcium signals while robustly decreasing their frequency. Simultaneously, ethanol decreased microvessel diameter. In females, ethanol did not change the amplitude or frequency of calcium signals from CA1 neurons but decreased microvessel diameter. A linear regression of ethanol-induced reduction in number of active neurons and microvessel constriction revealed a positive correlation (R = 0.981) in females. Together, these data demonstrate the feasibility of simultaneously evaluating neuronal and vascular components of alcohol actions in a deep brain area in freely moving mice, as well as the sexual dimorphism of hippocampal neurovascular responses to alcohol. [ABSTRACT FROM AUTHOR]

Sex trafficking constitutes a severe international issue, affecting 4.8 million victims worldwide, with those affected in the United States numbering in the thousands (Global Slavery Index, 2016). Despite this, little is known about the characteristics of sex traffickers, especially female sex traffickers. This paper aimed to increase our knowledge of female sex traffickers in the United States. 44 criminally prosecuted cases of sex trafficking involving female sex traffickers were examined, obtained through the Case Law Database within the Human Trafficking Knowledge Portal provided by the United Nations Office on Drugs and Crime. The study sought to explore characteristics of female sex traffickers in the United States with regards to the roles they hold, duties they perform and the makeup of their operations. Overall, findings demonstrated that women permeate the entire spectrum of sex trafficking crimes, from aiding and abetting to being ringleaders of sex trafficking rings. [ABSTRACT FROM AUTHOR]

Background: Small intestinal stromal tumors (SISTs) are a rare type of mesenchymal tumor. Gender is known to influence the incidence and prognosis of various tumors, but its role on the survival of SISTs at the population level remains unclear. Therefore, we aim to explore the relationship between gender and the prognosis of SISTs using the Surveillance, Epidemiology, and End Results (SEER) database., Methods: Data on SISTs patients from 2000 to 2019 were derived from the SEER database. Multiple imputation was used to address missing data. Kaplan-Meier analyses and Cox proportional hazard models were applied to evaluate the impact of demographic and clinical characteristics on overall survival (OS) and cancer-specific survival (CSS)., Results: A total of 3513 patients with SISTs were analyzed, including 1921 males and 1592 females. Kaplan-Meier analysis coupled with log-rank testing demonstrated a significantly higher mortality rate among male patients compared to females (P < 0.001). Notably, female patients exhibited superior OS (hazard ratio [HR] 0.808, 95% confidence interval [CI] 0.724-0.902, P < 0.001) and CSS (HR 0.801, 95% CI 0.692-0.927, P = 0.003) compared to male patients. While the mean 1-year CSS rates were comparable between genders (95.3% for males vs. 96.0% for females, P = 0.332), male patients consistently showed lower mean survival rates at 3-, 5-, and 10-year intervals. Surgical intervention significantly boosted 5-year OS and CSS rates in both male and female patients (P < 0.001). Multivariate Cox regression analysis identified age, sex, grade, TNM stage, surgery, and mitotic rate as independent risk factors for OS and CSS in patients with SISTs., Conclusions: Our findings suggest that male patients with SISTs have a higher risk of mortality compared to female patients, indicating that gender may serve as a predictive indicator for survival in this patient population., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The gastrointestinal tract harbors a densely populated community of microbes that exhibits sexual dimorphism. Dysbiosis of this community has been associated with chronic human disease states ranging from metabolic diseases to neuropsychiatric disorders (NPDs). The gut microbiota–gut–brain axis (GMGBA) is a bi-directional pathway that facilitates the interaction of the gut microflora with host physiological functions. Recently, research surrounding the potential roles of the GMGBA in the development of NPDs (e.g., depression, anxiety, and autism spectrum disorders (ASDs)) has increased. However, the role of the GMGBA in attention-deficit/hyperactivity disorder (ADHD), an NPD that affects an estimated 8.4% of children (5.1% of female and 11.5% of male children) and 4% of adults (with a male–female odds ratio of 1.6) in the United States, remains understudied. Herein, we synthesize the current literature regarding the GMGBA, ADHD, and the potentially relevant intersections between the GMGBA and ADHD. Recommendations are presented for pathways of future research into the role(s) of the GMGBA in ADHD etiology and symptomatology. Particular focus is given to the potential for the variable of host sex to act as an outcome modifier of the relationship between the GMGBA and ADHD. [ABSTRACT FROM AUTHOR]

Sex differences in cancer incidence and survival are constant and pronounced globally, across all races and all age groups of cancer types. In 2016, after the National Institutes of Health proposed a policy of utilizing sex as a biological variable, researchers started paying more attention to the molecular mechanisms behind gender variations in cancer. Historically, most previous studies investigating sex differences have been centered on gonadal sex hormones. Nevertheless, sex differences also involve genetic and molecular pathways that run throughout the entire process of cancer cell proliferation, metastasis, and treatment response, in addition to sex hormones. In particular, there is significant gender dimorphism in the efficacy and toxicity of oncology treatments, including conventional radiotherapy and chemotherapy, as well as the emerging targeted therapies and immunotherapy. To be clear, not all mechanisms will exhibit gender bias, and not all gender bias will affect cancer risk. Our goal in this review is to discuss some of the significant sex-related changes in fundamental cancer pathways. To this purpose, we summarize the differential impact of gender on cancer development in three dimensions: sex hormones, genetics, and epigenetics, and focus on current hot subjects including tumor suppressor function, immunology, stem cell renewal, and non-coding RNAs. Clarifying the essential mechanisms of gender differences will help guide the clinical treatment of both sexes in tumor radiation and chemotherapy, medication therapy with various targets, immunotherapy, and even drug development. We anticipate that sex-differentiated research will help advance sex-based cancer personalized medicine models and encourage future basic scientific and clinical research to take sex into account., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Abstract: Biological sex is a primary determinant of athletic performance because of fundamental sex differences in anatomy and physiology dictated by sex chromosomes and sex hormones. Adult men are typically stronger, more powerful, and faster than women of similar age and training status. Thus, for athletic events and sports relying on endurance, muscle strength, speed, and power, males typically outperform females by 10%-30% depending on the requirements of the event. These sex differences in performance emerge with the onset of puberty and coincide with the increase in endogenous sex steroid hormones, in particular testosterone in males, which increases 30-fold by adulthood, but remains low in females. The primary goal of this consensus statement is to provide the latest scientific knowledge and mechanisms for the sex differences in athletic performance. This review highlights the differences in anatomy and physiology between males and females that are primary determinants of the sex differences in athletic performance and in response to exercise training, and the role of sex steroid hormones (particularly testosterone and estradiol). We also identify historical and nonphysiological factors that influence the sex differences in performance. Finally, we identify gaps in the knowledge of sex differences in athletic performance and the underlying mechanisms, providing substantial opportunities for high-impact studies. A major step toward closing the knowledge gap is to include more and equitable numbers of women to that of men in mechanistic studies that determine any of the sex differences in response to an acute bout of exercise, exercise training, and athletic performance., (Copyright © 2023 by the American College of Sports Medicine.)

Objective: Cardiometabolic disease is the leading cause of mortality in the United States. Cardiometabolic function during adolescence predicts future cardiometabolic disease, yet few studies have examined early determinants of cardiometabolic function. Informed by evidence of sex differences in the prevalence and severity of cardiometabolic disorders and evidence of sexual dimorphism in the stress response, we examined sex differences in the association between living in poverty and cardiometabolic function during adolescence, a precursor of later cardiometabolic disorders. Methods: We linked data from 10 415 adolescents aged 12-19 in the National Health and Nutrition Examination Survey (1999-2012) with US Census–tract data on area-level poverty (percentage of the population living in poverty, grouped into quartiles). We parameterized cardiometabolic dysfunction by summing the z scores of 6 cardiometabolic biomarkers, grouped into quintiles. Hierarchical ordinal models estimated associations. Results: Compared with residents in low-poverty areas, residents in high-poverty areas had elevated odds of cardiometabolic dysfunction (highest quartile of poverty odds ratio [OR] = 1.27; 95% confidence interval [CI], 1.08-1.50). This association was more pronounced among boys than girls (highest quartile of poverty for boys: OR = 1.36; 95% CI, 1.10-1.70; highest quartile of poverty for girls: OR = 1.17; 95% CI, 0.94-1.47). Conclusion: Our study supports the existence of sex-specific associations. These results highlight the potential for community-based programs, such as housing assistance, to improve population health. [ABSTRACT FROM AUTHOR]

Many turtle species have temperature-dependent sex determination (TSD), raising the prospect that climate change could impact population dynamics by altering sex ratios. Understanding how climate change will affect populations of animals with TSD requires a reliable and minimally invasive method of identifying the sexes of young individuals. This determination is challenging in many turtles, which often lack conspicuous external sexual dimorphism until years after hatching. Here, we explore four alternatives for sexing three age classes of captive-reared young gopher tortoises (Gopherus polyphemus), a terrestrial turtle of conservation concern native to the southeastern United States: (1) naive testosterone levels, (2) testosterone levels following a follicle stimulating hormone (FSH) challenge, (3) linear morphological measurements, and (4) geometric morphometrics. Unlike some other turtle species, male and female neonatal gopher tortoises have overlapping naive testosterone concentration distributions, justifying more complicated methods. We found that sex of neonates (<7 days old) is best predicted by a "random forest'' machine learning model with naive testosterone levels and morphological measurements (8% out-of-bag error). Sex of hatchlings (4-8 months old) was predicted with 11% error using a simple threshold on naive testosterone levels, or with 4% error using a simple threshold on post-FSH testosterone levels. Sex of juveniles (approximately 3.5 years old) was perfectly predicted using a simple threshold on naive testosterone levels. Sexing hatchlings at >4 months of age is the easiest and most reliable non-surgical method for sex identification. Given access to a rearing facility and equipment to perform hormone assays, these methods have the potential to supplant laparoscopic surgery as the method of choice for sexing young gopher tortoises. [ABSTRACT FROM AUTHOR]

Studies of colorism-the idea that racial hierarchies coexist with gradational inequalities based on skin color-consistently find that darker skin correlates with lower socioeconomic outcomes. Despite the causal nature of this debate, evidence remains predominantly associational. This study revisits the colorism literature by proposing a causal model underlying these theories. It discusses conditions under which associations may reflect contemporary causal effects of skin color and evaluates strategies for identifying these effects. Using data from the AddHealth and NLSY97 surveys and applying two identification strategies, the study estimates the causal effects of skin color on college degree attainment, personal earnings, and family income among White, Black, and Hispanic populations in the United States. Results show that darker skin correlates with poorer educational and economic outcomes within racial groups. However, evidence of contemporary causal effects of skin color is partial, limited to college attainment of Whites and family income of Hispanics. For Blacks, results suggest a generalized penalty associated with being Black rather than gradation based on skin tone. Methodologically, the article advocates using sensitivity analyses to account for unobserved confounders in models for skin color effects and uses sibling fixed-effects as a secondary complementary strategy. [ABSTRACT FROM AUTHOR]

The primacy of endozoochory for the maintenance and expansion of many woody plant populations is well known, but seed dispersal is not well understood for most species. This is especially true for rare species, where small population size and low fruit production can limit field- or observation-based experiments. Additionally, the effect of environmental heterogeneity on disperser movement is rarely investigated but has been shown to improve estimates of plant population spatial patterns and dynamics. We used simulation experiments to explore the effects of environmental heterogeneity and disperser movement on Lindera subcoriacea seed dispersal, a rare shrub from the southeastern United States with avian-dispersed seeds. Our experiments incorporated environmental heterogeneity and simulated disperser movement for five bird species, based on either landscape permeability or straight path rules. We anticipated that permeability-based movement would result in greater dispersal distances and seed dispersal effectiveness, which characterizes both quantity and quality. Generally, we did not find differences in seed dispersal between permeability and straight path experiments. However, we did find that permeability-based experiments had greater deposition into suitable habitat during flight (23 vs. 1%). These rare but longer distance depositions may be especially important for plants that are influenced by gap or interpopulation dynamics. We also found consistently greater dispersal into high quality habitats regardless of disperser species in permeability experiments, implying that incorporating species-specific assessments of landscape utilization (occupancy) could influence the effectiveness of seed dispersal. Our study suggests that including environmental heterogeneity in seed dispersal models can provide additional insights not provided by avian parameters (e.g., gut capacity, seed retention time, and flight speed) commonly used to inform dispersal models. [ABSTRACT FROM AUTHOR]

Background: Rural regions of the western United States have experienced a noticeable surge in both the frequency and severity of acute wildfire events, which brings significant challenges to both public safety and environmental conservation efforts, with impacts felt globally. Identifying factors contributing to immune dysfunction, including endocrinological phenotypes, is essential to understanding how hormones may influence toxicological susceptibility. Methods: This exploratory study utilized male and female C57BL/6 mice as in vivo models to investigate distinct responses to acute woodsmoke (WS) exposure with a focus on sex-based differences. In a second set of investigations, two groups were established within the female mouse cohort. In one group, mice experienced ovariectomy (OVX) to simulate an ovarian hormone-deficient state similar to surgical menopause, while the other group received Sham surgery as controls, to investigate the mechanistic role of ovarian hormone presence in driving immune dysregulation following acute WS exposure. Each experimental cohort followed a consecutive 2-day protocol with daily 4-h exposure intervals under two conditions: control HEPA-filtered air (FA) and acute WS to simulate an acute wildfire episode. Results: Metals analysis of WS particulate matter (PM) revealed significantly increased levels of 63Cu, 182W, 208Pb, and 238U, compared to filtered air (FA) controls, providing insights into the specific metal components most impacted by the changing dynamics of wildfire occurrences in the region. Male and female mice exhibited diverse patterns in lung mRNA cytokine expression following WS exposure, with males showing downregulation and females displaying upregulation, notably for IL-1β, TNF-α, CXCL-1, CCL-5, TGF-β, and IL-6. After acute WS exposure, there were notable differences in the responses of macrophages, neutrophils, and bronchoalveolar lavage (BAL) cytokines IL-10, IL-6, IL-1β, and TNF-α. Significant diverse alterations were observed in BAL cytokines, specifically IL-1β, IL-10, IL-6, and TNF-α, as well as in the populations of immune cells, such as macrophages and polymorphonuclear leukocytes, in both Sham and OVX mice, following acute WS exposure. These findings elucidated the profound influence of hormonal changes on inflammatory outcomes, delineating substantial sex-related differences in immune activation and revealing altered immune responses in OVX mice due to ovarian hormone deficiency. In addition, the flow cytometry analysis highlighted the complex interaction between OVX surgery, acute WS exposure, and their collective impact on immune cell populations within the hematopoietic bone marrow niche. Conclusions: In summary, both male and female mice, alongside females subjected to OVX and those who had sham surgery, exhibit significant variations in the expression of proinflammatory cytokines, chemokines, lung mRNA gene expression, and related functional networks linked to signaling pathways. These differences potentially act as mediators of sex-specific and hormonal influences in the systemic inflammatory response to acute WS exposure during a wildfire event. Understanding the regulatory roles of genes expressed differentially under environmental stressors holds considerable implications, aiding in identifying sex-specific therapeutic targets for addressing acute lung inflammation and injury. [ABSTRACT FROM AUTHOR]

Clinical management of sacroiliac disease has proven challenging from both diagnostic and therapeutic perspectives. Although it is widely regarded as a common source of low back pain, little consensus exists on the appropriate clinical management of sacroiliac joint pain and dysfunction. Understanding the biomechanics, innervation, and function of this complex load bearing joint is critical to formulating appropriate treatment algorithms for SI joint disorders. ASPN has developed this comprehensive practice guideline to serve as a foundational reference on the appropriate management of SI joint disorders utilizing the best available evidence and serve as a foundational guide for the treatment of adult patients in the United States and globally. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a leading cause of chronic pain and disability, not only in the United States but also worldwide. The burden of OA is higher in women than in men. Estrogen as a possible explanation for observed sex differences in OA has not been definitively established. The purpose of this review was to summarize the results from studies of estrogen, estrogen depletion and treatment, and their impact on knee, hip, hand, and spine OA. We conducted a targeted review of the literature using PubMed. Although several studies show that hormone replacement therapy has the potential to be protective of OA for some joints, there are studies that showed no protective effect or even adverse effect. Taken together, the evidence for the protective effect of estrogen therapy depends on OA joint, OA out-come, and study design. Although this area has been studied for decades, more exclusively since the 1990s, there is a lack of high-quality experimental research in this topic. The lack of definitive conclu-sion on whether estrogen can play a role in the development in OA of either the knee, hip, spine, or hand is often in part due to the noncomparability of studies existing within the literature. Differences in diagnostic criteria, imaging modalities, populations studied, study designs, and outcome measures, as well as random error, have all contributed to inconclusive evidence. Future research on the role of estrogen in OA is needed, particularly as global demographic shifts in increasing overweight/obesity prevalence and ageing populations may contribute to widening OArelated health inequalities. [ABSTRACT FROM AUTHOR]