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Demographic and genetic connectivity have important implications for population dynamics of wildlife and their ability to adapt to changing environments. Landscape features such as roads and streams can inhibit movement of species with poor dispersal capabilities and exacerbate the effects of habitat fragmentation. Terrestrial plethodontid salamanders are generally thought of as incapable of long‐distance movement and may vary in their motivation to move across a landscape by sex and size classes. To examine landscape permeability to movement, we assessed how distance and natural or man‐made landscape features affect recapture rates after displacement in red‐backed salamanders (Plethodon cinereus). We randomly assigned marked salamanders from 6 plots at Camp Karoondinha in Millmont, Pennsylvania, USA, to a control (placed under the same cover board) or a treatment (displaced 25 m or 50 m through the forest or across a stream or road). Of 290 marked individuals, we recaptured 29.8%. We recaptured more individuals in the control treatment compared to displaced individuals, with recapture rates decreasing with the presence of a road or stream. Landscape feature type and sex did not affect the probability of recapture, but developmental stage did, with adult salamanders more likely to be recaptured than juvenile salamanders. Our results suggest that landscape permeability is reduced for terrestrial salamanders when a landscape feature is present compared to open forest. Narrow, dirt roads present a similar challenge to a natural stream for red‐backed salamanders. Our study should be of value to land managers who are concerned about the negative effects of landscape permeability on terrestrial salamander populations. [ABSTRACT FROM AUTHOR]

Background: High quality data pertaining to the size of the transgender and gender diverse (TGD) population are scant, however, several recently published studies may provide more reliable contemporary estimates. Aims: To summarize the estimated number and proportion of TGD individuals overall and across age groups, based on most accurate data. Methods: This systematic review focused on recent studies (published from 2009 through 2019) that utilized sound methodology in assessing the proportion of TGD people in the general population. Publications were included if they used clear definitions of TGD status, and calculated proportions based on a well-defined sampling frame. Nineteen eligible publications represented two broad categories of studies: those that used data from large health care systems; and those that identified TGD individuals from population surveys. Results: Among health system-based studies, TGD persons were identified using relevant diagnostic codes or clinical notes. The proportions of individuals with a TGD-relevant diagnosis or other recorded evidence ranged between 17 and 33 per 100,000 enrollees. In population surveys TGD status was ascertained based on self-report with either narrow or broad definitions. The survey-based estimates were orders of magnitude higher and consistent across studies using similar definitions. When the surveys specifically inquired about 'transgender' identity, the estimates ranged from 0.3% to 0.5% among adults, and from 1.2% to 2.7% among children and adolescents. When the definition was expanded to include broader manifestations of 'gender diversity', the corresponding proportions increased to 0.5-4.5% among adults and 2.5-8.4% among children and adolescents. Upward temporal trends in the proportion of TGD people were consistently observed. Conclusions: Current data indicate that people who self-identify as TGD represent a sizable and increasing proportion of the g [ABSTRACT FROM AUTHOR]

Summary: Seed development largely depends on the long‐distance transport of sucrose from photosynthetically active source leaves to seed sinks. This source‐to‐sink carbon allocation occurs in the phloem and requires the loading of sucrose into the leaf phloem and, at the sink end, its import into the growing embryo. Both tasks are achieved through the function of SUT sucrose transporters. In this study, we used vegetable peas (Pisum sativum L.), harvested for human consumption as immature seeds, as our model crop and simultaneously overexpressed the endogenous SUT1 transporter in the leaf phloem and in cotyledon epidermal cells where import into the embryo occurs. Using this 'Push‐and‐Pull' approach, the transgenic SUT1 plants displayed increased sucrose phloem loading and carbon movement from source to sink causing higher sucrose levels in developing pea seeds. The enhanced sucrose partitioning further led to improved photosynthesis rates, increased leaf nitrogen assimilation, and enhanced source‐to‐sink transport of amino acids. Embryo loading with amino acids was also increased in SUT1‐overexpressors resulting in higher protein levels in immature seeds. Further, transgenic plants grown until desiccation produced more seed protein and starch, as well as higher seed yields than the wild‐type plants. Together, the results demonstrate that the SUT1‐overexpressing plants with enhanced sucrose allocation to sinks adjust leaf carbon and nitrogen metabolism, and amino acid partitioning in order to accommodate the increased assimilate demand of growing seeds. We further provide evidence that the combined Push‐and‐Pull approach for enhancing carbon transport is a successful strategy for improving seed yields and nutritional quality in legumes. Significance Statement: We demonstrate that carbon allocation from source to sink and seed carbon pools can be improved in legumes through synergistically enhancing leaf export and seed uptake of sucrose. In addition, changes in source‐to‐sink carbon transport affect seed protein levels though improved leaf metabolism and amino acid partitioning to, and uptake into, the embryo. [ABSTRACT FROM AUTHOR]