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Public attention to climate change challenges our locked-in fossil fuel-dependent energy sector. Natural gas is replacing other fossil fuels in our energy mix. One way to reduce the greenhouse gas (GHG) impact of fossil natural gas is to replace it with renewable natural gas (RNG). The benefits of utilizing RNG are that it has no climate change impact when combusted and utilized in the same applications as fossil natural gas. RNG can be injected into the gas grid, used as a transportation fuel, or used for heating and electricity generation. Less common applications include utilizing RNG to produce chemicals, such as methanol, dimethyl ether, and ammonia. The GHG impact should be quantified before committing to RNG. This study quantifies the potential production of biogas (i.e., the precursor to RNG) and RNG from agricultural and waste sources in New York State (NYS). It is unique because it is the first study to provide this analysis. The results showed that only about 10% of the state’s resources are used to generate biogas, of which a small fraction is processed to RNG on the only two operational RNG facilities in the state. The impact of incorporating a second renewable substitute for fossil natural gas, “green” hydrogen, is also analyzed. It revealed that injecting RNG and “green” hydrogen gas into the pipeline system can reduce up to 20% of the state’s carbon emissions resulting from fossil natural gas usage, which is a significant GHG reduction. Policy analysis for NYS shows that several state and federal policies support RNG production. However, the value of RNG can be increased 10-fold by applying a similar incentive policy to California’s Low Carbon Fuel Standard (LCFS). 

Gender equity in academia is a long-standing struggle. Although common to all disciplines, the impacts of bias and stereotypes are particularly pronounced in science, technology, engineering and mathematics (STEM) disciplines. This paper explores what barriers exist for the career progression of women in academia in STEM disciplines in order to identify key issues and potential solutions. In particular, we were interested in how women perceive the barriers affecting their careers in comparison to their male colleagues. Fourteen focus groups with female-identifying academics showed that there were core barriers to career progression, which spanned countries, disciplines and career stages. Entrenched biases, stereotypes, double standards, bullying and harassment all negatively impact women’s confidence and sense of belonging. Women also face an additional biological burden, often being pushed to choose between having children or a career. Participants felt that their experiences as STEM academics were noticeably different to those of their male colleagues, where many of the commonly occurring barriers for women were simply non-issues for men. The results of this study indicate that some of these barriers can be overcome through networks, mentoring and allies. Addressing these barriers requires a reshaping of the gendered norms that currently limit progress to equity and inclusion. 

Preventing extinctions requires understanding macroecological patterns of vulnerability or persistence. However, correlates of risk can be nonlinear, within-species risk varies geographically, and current-day threats cannot reveal drivers of past losses. We investigated factors that regulated survival or extinction in Caribbean mammals, which have experienced the globally highest level of human-caused postglacial mammalian extinctions, and included all extinct and extant Holocene island populations of non-volant species (219 survivals or extinctions across 118 islands). Extinction selectivity shows a statistically detectable and complex body mass effect, with survival probability decreasing for both mass extremes, indicating that intermediate-sized species have been more resilient. A strong interaction between mass and age of first human arrival provides quantitative evidence of larger mammals going extinct on the earliest islands colonized, revealing an extinction filter caused by past human activities. Survival probability increases on islands with lower mean elevation (mostly small cays acting as offshore refugia) and decreases with more frequent hurricanes, highlighting the risk of extreme weather events and rising sea levels to surviving species on low-lying cays. These findings demonstrate the interplay between intrinsic biology, regional ecology and specific local threats, providing insights for understanding drivers of biodiversity loss across island systems and fragmented habitats worldwide. 

Comprising more than 1,400 species, bats possess adaptations unique among mammals including powered flight, unexpected longevity, and extraordinary immunity. Some of the molecular mechanisms underlying these unique adaptations includes DNA repair, metabolism and immunity. However, analyses have been limited to a few divergent lineages, reducing the scope of inferences on gene family evolution across the Order Chiroptera. We conducted an exhaustive comparative genomic study of 37 bat species, one generated in this study, encompassing a large number of lineages, with a particular emphasis on multi-gene family evolution across immune and metabolic genes. In agreement with previous analyses, we found lineage-specific expansions of the APOBEC3 and MHC-I gene families, and loss of the proinflammatory PYHIN gene family. We inferred more than 1,000 gene losses unique to bats, including genes involved in the regulation of inflammasome pathways such as epithelial defense receptors, the natural killer gene complex and the interferon-gamma induced pathway. Gene set enrichment analyses revealed genes lost in bats are involved in defense response against pathogen-associated molecular patterns and damage-associated molecular patterns. Gene family evolution and selection analyses indicate bats have evolved fundamental functional differences compared to other mammals in both innate and adaptive immune system, with the potential to enhance anti-viral immune response while dampening inflammatory signaling. In addition, metabolic genes have experienced repeated expansions related to convergent shifts to plant-based diets. Our analyses support the hypothesis that, in tandem with flight, ancestral bats had evolved a unique set of immune adaptations whose functional implications remain to be explored. 

Abstract Gender biases and stereotypes are prevalent in science, technology, engineering and mathematics (STEM) fields, which can create obstacles for the attraction, retention and progression of girls and women to STEM studies and careers. There are many initiatives which are used to attempt to address these biases and stereotypes, including the use of visible role models. This study explores the perceptions of the stereotypes applied to female STEM professionals who publicly speak about their work in both academic and non-academic settings. Using workshops with over 300 participants, predominantly female STEM professionals, from over 25 different cultural backgrounds, the results showed women who publicly communicate their work are likely to be stereotyped as ‘bitchy’, ‘bossy’, and ‘emotional’—often by their own gender. These findings suggest that women may be in a more vulnerable position when communicating publicly about their work, which could have implications for them participating fully in their careers. It may also have implications for programs which use role models to address prevailing STEM stereotypes. Systematic cultural and institutional change is needed in STEM fields to address the underlying bias and negative stereotypes facing women. However, it should be ensured that the intended solutions to facilitate this change are not compounding the problem.