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Chemical methods for the extraction and refinement of technologically critical rare earth elements (REEs) are energy-intensive, hazardous, and environmentally destructive. Current biobased extraction systems rely on extremophilic organisms and generate many of the same detrimental effects as chemical methodologies. The mesophilic methylotrophic bacterium Methylobacterium extorquens AM1 was previously shown to grow using electronic waste by naturally acquiring REEs to power methanol metabolism. Here we show that growth using electronic waste as a sole REE source is scalable up to 10 L with consistent metal yields without the use of harsh acids or high temperatures. The addition of organic acids increases REE leaching in a nonspecific manner. REE-specific bioleaching can be engineered through the overproduction of REE-binding ligands (called lanthanophores) and pyrroloquinoline quinone. REE bioaccumulation increases with the leachate concentration and is highly specific. REEs are stored intracellularly in polyphosphate granules, and genetic engineering to eliminate exopolyphosphatase activity increases metal accumulation, confirming the link between phosphate metabolism and biological REE use. Finally, we report the innate ability of M. extorquens to grow using other complex REE sources, including pulverized smartphones, demonstrating the flexibility and potential for use as a recovery platform for these critical metals.

Terpenes are diverse specialized metabolites naturally found within plants and have important roles in inter-species communication, adaptation and interaction with the environment. Their industrial applications span a broad range, including fragrances, flavors, cosmetics, natural colorants to agrochemicals and therapeutics, yet formal chemical synthesis is economically challenging due to structural complexities. Engineering terpene biosynthesis could represent an alternative in microbial biotechnological workhorses, such as Saccharomyces cerevisiae or Escherichi coli, utilizing sugars or complex media as feedstocks. Host species that metabolize renewable and affordable carbon sources may offer unique sustainable biotechnological alternatives. Methylotrophs are bacteria with the capacity to utilize one-carbon feedstocks, such as methanol or formate. They colonize the phyllosphere (above-ground area) of plants, and many accumulate abundant carotenoid pigments. Methylotrophs have the capacity to take up and use a subset of the rare earth elements known as lanthanides. These metals can enhance one-carbon (methylotrophic) metabolism. Here, we investigated whether manipulating the metabolism enables and enhances terpene production. A carotenoid-deficient mutant potentially liberates carbon, which may contribute to bioproduct accumulation. To test this hypothesis, terpene-producing bacterial strains regulated by two distinct promoters were generated. Wildtype Methylobacterium extorquens, ∆Meta1_3665, a methylotrophic mutant lacking the carotenoid pathway, and an E. coli strain were transformed with an exogenous terpene pathway and grown both in the presence and absence of lanthanides. The extraction, and the comparison of analytical profiles, provided evidence that engineered cultured M. extorquens under control of a native, inducible methylotrophic promoter can yield the sesquiterpene patchoulol when supplemented with lanthanide. In contrast, using a moderate-strength constitutive promoter failed to give production. We demonstrated colonization of the phyllosphere with the engineered strains, supporting the future engineering of selected species of the plant microbiome and with promising implications for the synthetic biology of small molecules.

Mixtecs and Zapotecs, originating from the Oaxaca area in Mexico, are among the largest indigenous groups of workers in California. Many adults in this community only access the health care system when sick and as a last resort. This article describes the development of a radionovela to inform the community about the importance of preventive health care. It was developed following the Sabido Method. The methodology to develop a radionovela may be of interest to other public health practitioners who want to develop educational materials in an engaging format, especially for communities that rely on oral, not written information.

This research is based on the uniqueness of the national tests scores in Colombia where the same students take a standardized test both at the end of high school and at the end of college. We use then the information of the labor market to identify the return to college education once the graduates find a job. The findings suggest that there is heterogeneity in the return of education than varies according to the university attended by the graduate. The wage premium for graduation from a top-ranked university is around 12%, and the penalty for graduating from a bottom-ranked university is close to 10%, and higher than the estimated wage gender gap of 8%. The research controls by innate ability using exit test scores to mitigate self-selection bias, or bias generated for specific job market skills provided in top-ranked universities. Location and major chosen are determinants of the variation in wages. The results are adjusted by these factors.

Lanthanide elements have been recently recognized as "new life metals" yet much remains unknown regarding lanthanide acquisition and homeostasis. In Methylorubrum extorquens AM1, the periplasmic lanthanide-dependent methanol dehydrogenase XoxF1 produces formaldehyde, which is lethal if allowed to accumulate. This property enabled a transposon mutagenesis study and growth studies to confirm novel gene products required for XoxF1 function. The identified genes encode an MxaD homolog, an ABC-type transporter, an aminopeptidase, a putative homospermidine synthase, and two genes of unknown function annotated as orf6 and orf7. Lanthanide transport and trafficking genes were also identified. Growth and lanthanide uptake were measured using strains lacking individual lanthanide transport cluster genes, and transmission electron microscopy was used to visualize lanthanide localization. We corroborated previous reports that a TonB-ABC transport system is required for lanthanide incorporation to the cytoplasm. However, cells were able to acclimate over time and bypass the requirement for the TonB outer membrane transporter to allow expression of xoxF1 and growth. Transcriptional reporter fusions show that excess lanthanides repress the gene encoding the TonB-receptor. Using growth studies along with energy dispersive X-ray spectroscopy and transmission electron microscopy, we demonstrate that lanthanides are stored as cytoplasmic inclusions that resemble polyphosphate granules.

Originating from one of the poorest areas in Mexico, Mixtecs are one of the largest indigenous groups of workers in California. Providing health education to this group is challenging because many do not speak English or Spanish, and indigenous languages are mainly oral, not written. We explored the feasibility of conveying health information through the radio and in promotora-led workshops. The study included an evaluation of the workshops through surveys before the workshop and 4 to 6 months later in a subsample of 96 indigenous women. The number of radio listeners averaged more than 2,000 per month, and 500 community members attended a workshop. Among women who completed pre- and postworkshop assessments (N = 75), there was a statistically significant increase in knowledge of how to get a wellness visit, where to get a free mammogram, and mammography screening guidelines. Women who ever had a mammogram or wellness visit at baseline were significantly more likely to report receipt of this service during the follow-up period than women who never had this service. Educational workshops and radio are promising and culturally appropriate strategies to provide health information in this community. However, many women need additional assistance to navigate access to health care.

In this article we rite/write, as an act of shamanic enfleshment, into knowing-being a decolonizing and feminist political subjectivity that centres the divine feminine and feminist spirituality of the abuelas. We journey across the territories of Colombia and so-called Australia and with the archetypes of Bachué, la Mujer Salvaje, la Mujer Amante-Hechicera, and Baubo, ella quien habla por la entrepierna. We rite/write to bring to presence the role that the erotic, the cyclical, and enfleshed can bring to our politics so that it weaves a sacred erotic political sociality, other registers of kinship/homecoming and (political) subjectivity, and a politics (m)otherwise in which no one is left behind and the racialized and feminized body is returned to its rightful place in our visions and onto epistemological practices of healing liberations. [ABSTRACT FROM AUTHOR]

Introduction: Central venous catheters (CVC) are a major contributor to infections in hemodialysis (HD) patients, leading to high morbidity and mortality. Gentamicin‐citrate (GC) lock is used as standard of care at centers belonging to a mid‐size dialysis organization. Four outpatient HD centers acquired by the organization continued to use heparin for catheter locks for a period of time before converting to the provider's standard of using GC lock. Methods: In this retrospective observational study, we included patients receiving HD by CVC at these four centers. We report rates of CVC‐related bloodstream infections (CVC‐BSI) during the heparin lock and the GC lock periods; crude rate ratios and adjusted rate ratios using Cox survival analyses adjusting for potential confounders; microbiology patterns; safety signals (gentamicin resistance, hospitalizations and deaths); and financial impact on payer. Findings: A total of 220 and 281 patients used tunneled CVCs, accounting for 25,245 and 44,550 catheter days in the heparin and the GC lock periods, respectively. CVC‐BSI event rates were 66% lower in the GC lock period (CVC‐BSI event rate: 0.20 per 1000 catheter‐days) than the heparin lock period (rate: 0.59 per 1000 catheter days); rate ratio 0.34 (95% confidence interval (CI) 0.15–0.78, P = 0.01). In the fully adjusted multivariable Cox model, use of GC lock was associated with 70% reduction in CVC‐BSI events (HR 0.30, 95% CI 0.12–0.72, P = 0.01). No increased risk of gentamicin resistance, hospitalizations, or death associated with use of GC lock were observed. Use of GC lock was associated with an estimated saving of $1533 (95% CI: $259–$4882) per patient per year. Discussion: Use of GC lock led to significant reductions in CVC‐BSIs with no signal for harm, and is associated with significant cost savings in dialysis care. [ABSTRACT FROM AUTHOR]