Photochemistry of aqueous pyruvic acid

The study of organic chemistry in atmospheric aerosols and cloud formation is of interest in predictions of air quality and climate change. It is now known that aqueous phase chemistry is important in the formation of secondary organic aerosols. Here, the photoreactivity of pyruvic acid (PA; CH₃COCOOH) is investigated in aqueous environments characteristic of atmospheric aerosols. PA is currently used as a proxy for α-dicarbonyls in atmospheric models and is abundant in both the gas phase and the aqueous phase (atmospheric aerosols, fog, and clouds) in the atmosphere. The photoreactivity of PA in these phases, however, is very different, thus prompting the need for a mechanistic understanding of its reactivity in different environments. Although the decarboxylation of aqueous phase PA through UV excitation has been studied for many years, its mechanism and products remain controversial. In this work, photolysis of aqueous PA is shown to produce acetoin (CH₃CHOHCOCH₃), lactic acid (CH₃CHOHCOOH), acetic acid (CH₃COOH), and oligomers, illustrating the progression from a three-carbon molecule to four-carbon and even six-carbon molecules through direct photolysis. These products are detected using vibrational and electronic spectroscopy, NMR, and MS, and a reaction mechanism is presented accounting for all products detected. The relevance of sunlight-initiated PA chemistry in aqueous environments is then discussed in the context of processes occurring on atmospheric aerosols.     

Sexuality and gender: change through reflection and action

Gender and sexuality inequalities lie at the root of poor sexual and reproductive health (SRH). An India-based non-governmental organization (NGO) implemented a field-based methodology to integrate gender and sexuality into existing SRH projects in two states. Personal and organizational change occurred through critical analysis and experiential exercises which normalized topics on sexuality for program staff and communities. Staff learned how biases prevented them from engaging with communities. Community women came to understand sexual pleasure as an important aspect of strengthening the family and community. Mapping women's mobility revealed the link between sexuality, mobility and family honour. Gender myths, portraying men as oppressors, made explicit the narrow and biased picture of men that perpetuates through social norms maintained by staff and not only by communities in which they work. Methods improved social relations and prompted both behaviour and social changes at the community level.     

Biallelic Pathogenic GFRA1 Variants Cause Autosomal Recessive Bilateral Renal Agenesis

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