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Understanding the drivers of plant phenology is critical to predict the impact of future warming on terrestrial ecosystem carbon cycling and feedbacks to climate. Using indoor growth chambers, air humidity is reported to influence spring phenology in temperate trees. However, previous studies have not investigated the effect of air humidity on the spring phenology using long-term and large-scale ground observations. Therefore, the role of humidity in spring phenology in temperate trees still remains poorly understood. Here, we synthesized 229,588 records of leaf unfolding dates in eight temperate tree species, including four early-successional and four late-successional species, at 1716 observation sites during 1951-2015 in Europe, and comprehensively analyzed the effect of humidity on the spring phenology. We found that rising humidity significantly delayed spring leaf unfolding for all eight temperate tree species. Leaf unfolding was more sensitive to humidity in early-successional species compared to late-successional species. In addition, the delaying effect of humidity on leaf unfolding increased as temperature warmed over the past 65 years. Our results provide evidence that spring leaf unfolding of temperate trees was significantly delayed by rising humidity. The delaying effect of humidity may restrict earlier spring phenology induced by warming, especially for early-successional species, under future climate warming scenarios in temperate forests., Competing Interests: Declaration of competing interest The authors declare that they have no competing financial interests., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Project PRIDE (Promoting Resilience In Discriminatory Environments) is an 8-session small group intervention aimed at reducing negative mental and behavioral health outcomes resulting from minority stress. This study reports the results of a one-armed pilot test of Project PRIDE, which aimed to examine the feasibility and potential for efficacy of the intervention in a sample of 33 gay and bisexual men aged 18 to 25. The intervention appeared feasible to administer in two different sites and all participants who completed posttreatment (n = 22) or follow-up (n = 19) assessments reported high satisfaction with the intervention. Small to large effect sizes were observed for increases in self-esteem; small effect sizes were found for decreases in loneliness and decreases in minority stress variables; and small and medium effect sizes were found for reductions in alcohol use and number of sex partners, respectively. Overall, Project PRIDE appears to be a feasible intervention with promise of efficacy., (Copyright © 2017. Published by Elsevier Ltd.)

Sexual orientation-related discrimination experiences have been implicated in elevated rates of anxiety symptoms within sexual minority groups. Theory suggests that chronic discrimination experiences may dampen the ability to tolerate distress, increasing vulnerability for anxiety. This study examined the role of distress tolerance, or the capacity to withstand negative emotions, as a construct underlying associations between discriminatory experiences and anxiety among sexual minority adults. Participants (N=119;M age =36.4±14.8; 50% cisgender male, 31% cisgender female, 19% transgender; 37% non-Latino white) were recruited from Houston, Texas. Measures administered included the Heterosexist Harassment, Rejection, and Discrimination Scale (discrimination experiences), Distress Tolerance Scale (distress tolerance), and the State-Trait Inventory for Cognitive and Somatic Anxiety (anxiety). The association of discrimination experiences and anxiety through distress tolerance was assessed using covariate-adjusted mediation modeling. Results indicated that sexual orientation-related discrimination experiences were significantly and positively associated with anxiety and that this association was mediated through lower distress tolerance. Significant indirect effects were specific to cognitive (versus somatic) anxiety symptoms. Results suggest that distress tolerance may be an explanatory mechanism in the association between discriminatory experiences and cognitive symptoms of anxiety and a potentially relevant target within clinical interventions to address anxiety-related health disparities among sexual minority adults. However, more sophisticated designs are needed to delineate causal associations., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Biological sex differences and sociocultural gender diversity influence endocrine stress reactivity. Although numerous studies have shown that men typically activate stronger stress responses than women when exposed to laboratory-based psychosocial stressors, it is unclear whether sexual orientation further modulates stress reactivity. Given that lesbian, gay, and bisexual (LGB) individuals frequently report heightened distress secondary to stigma-related stressors, we investigated whether cortisol stress reactivity differs between LGB individuals and heterosexual individuals in response to a well-validated psychosocial stressor., Methods: The study population comprised 87 healthy adults (mean age, 25 years) who were grouped according to their biological sex and their gendered sexual orientation: lesbian/bisexual women (n = 20), heterosexual women (n = 21), gay/bisexual men (n = 26), and heterosexual men (n = 20). Investigators collected 10 salivary cortisol samples throughout a 2-hour afternoon visit involving exposure to the Trier Social Stress Test modified to maximize between-sex differences., Results: Relative to heterosexual women, lesbian/bisexual women showed higher cortisol stress reactivity 40 min after exposure to the stressor. In contrast, gay/bisexual men displayed lower overall cortisol concentrations throughout testing compared with heterosexual men. Main findings were significant while adjusting for sex hormones (estradiol-to-progesterone ratio in women and testosterone in men), age, self-esteem, and disclosure status (whether LGB participants had completed their "coming out")., Conclusions: Our results provide novel evidence for gender-based modulation of cortisol stress reactivity based on sexual orientation that goes beyond well-established between-sex differences. This study raises several important avenues for future research related to the physiologic functioning of LGB populations and gender diversity more broadly., (Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Recent advances in the large-scale sequencing of mammalian genomes have provided a means to study divergence in not only genic sequences but also in the non-coding bulk of DNA. There is evidence of significant variation in the levels of divergence between presumably neutral regions, pointing at an underlying variation in the rate of mutation across the genome. Apparently, such variation occurs on different scales, including sequence context effects (the influence of neighboring nucleotides on the rate of mutation at individual sites), variation within chromosomes (on the scales of kilobases as well as megabases), and between chromosomes (among autosomes as well as between autosomes and sex chromosomes). An important aspect for further research in this area is to study whether there is an ultimate evolutionary explanation for mutation rate variation within mammalian genomes.

Maternal-effect selfish genes such as Medea or Scat act to kill progeny that do not bear a copy of the selfish gene present in the mother. Previous models of this system allowed for two types of allele, the selfish (killer) type and the sensitive (susceptible) wild-type. These models predict that the invasion conditions of the selfish allele are quite broad and that if invasion is possible a high frequency equilibrium is to be expected. The selfish element is therefore predicted to persist. Here a hypothetical third allele that neither kills nor is killed (i.e. insensitive) is considered. Such an allele could enter a population by recombination, mutation or migration. The incorporation of this third allele profoundly affects the dynamics of the system and, under some parameter values, it is possible for the spread of the insensitive allele to lead, eventually, to the fixation of the wild-type allele (reversible evolution). This is most likely if the death of progeny provides no direct benefit to the surviving sibs (i.e. in the absence of fitness compensation), as in insects without gregarious broods. Under these circumstances the selfish element cannot spread when infinitely rare, only after having risen to some finite frequency. A fitness cost to bearing the killer allele then causes its loss. However, if fitness compensation is found (e.g. in placental mammals) the invasion of the selfish element from an infinitely low level is possible for a wide range of costs and both stable coexistences of all three alleles and limit cycles of all three are then found. It is therefore to be expected that in mammals selfish maternal-effect genes are more likely both to spread and to persist than in insects, due to their different levels of fitness compensation.