Free-flowing rivers (FFRs) support diverse, complex and dynamic ecosystems globally, providing important societal and economic services. Infrastructure development threatens the ecosystem processes, ...biodiversity and services that these rivers support. Here we assess the connectivity status of 12 million kilometres of rivers globally and identify those that remain free-flowing in their entire length. Only 37 per cent of rivers longer than 1,000 kilometres remain free-flowing over their entire length and 23 per cent flow uninterrupted to the ocean. Very long FFRs are largely restricted to remote regions of the Arctic and of the Amazon and Congo basins. In densely populated areas only few very long rivers remain free-flowing, such as the Irrawaddy and Salween. Dams and reservoirs and their up- and downstream propagation of fragmentation and flow regulation are the leading contributors to the loss of river connectivity. By applying a new method to quantify riverine connectivity and map FFRs, we provide a foundation for concerted global and national strategies to maintain or restore them.
•Household pollution from polluting fuels remains common in India, Mexico, and China.•Using polluting cooking fuels was associated with poorer cognition in each country.•Polluting cooking fuel use ...effects were equivalent to an additional 3-6 years of age.
Exposure to high levels of air pollution is associated with poor health, including worse cognitive function. Whereas many studies of cognition have assessed outdoor air pollution, we evaluate how exposure to air pollution from combustion of polluting household fuels relates with cognitive function using harmonized data from India, Mexico, and China.
We analyze adults age 50+ in three nationally representative studies of aging with common data collection methods: the 2017–2019 Longitudinal Aging Study in India (n = 50,532), 2015 Mexican Health and Aging Study (n = 12,883), and 2013 China Health and Retirement Longitudinal Study (n = 12,913). Use of polluting fuels was assessed by self-report of wood, coal, kerosene, crop residue, or dung for cooking. Cognitive function was measured by performance across several cognitive domains and summarized into a total cognition score. We used linear regression, by country, to test how polluting cooking fuel use relates with cognition adjusting for key demographic and socioeconomic factors.
Approximately 47%, 12%, and 48% of respondents in India, Mexico, and China, respectively, relied primarily on polluting cooking fuel, which was more common in rural areas. Using polluting cooking fuels was consistently associated with poorer cognitive function in all countries, independent of demographic and socioeconomic characteristics. Adjusted differences in cognitive function between individuals using polluting and clean cooking fuel were equivalent to differences observed between individuals who were 3 years of age apart in Mexico and China and 6 years of age apart in India. Across countries, associations between polluting cooking fuel use and poorer cognition were larger for women.
Results suggest that household air pollution from the use of polluting cooking fuel may play an important role in shaping cognitive outcomes of older adults in countries where reliance on polluting fuels for domestic energy needs still prevails. As these countries continue to age, public health efforts should seek to reduce reliance on these fuels.
Objective: To describe differences in cognitive functioning across rural and urban areas among older Mexican adults. Method: We include respondents aged 50+ in the 2012 Mexican Health and Aging Study ...(MHAS). Cognitive functioning by domain is regressed as a function of community size. The role of educational attainment in explaining rural/urban differences in cognitive functioning is examined. Results: Respondents residing in more rural areas performed worse across five cognitive domains. The majority, but not all, of the association between community size and cognitive functioning was explained by lower education in rural areas. Discussion: Respondents residing in more rural areas were disadvantaged in terms of cognitive functioning compared with those residing in more urban areas. Poorer cognitive functioning in late life may be the result of historical educational disadvantage in rural areas or selection through migration from rural to urban regions for employment.
Abstract
Objectives
Early-life disadvantage (ELD) relates to lower late-life cognition. However, personality factors, including having an internal locus of control (LOC) or a conscientious ...personality, relate to resilience and effective stress coping. We explore whether personality factors convey resilience against the negative effects of ELD on cognition, by gender, in Mexico.
Methods
Using the 2015 Mexican Health and Aging Study, we estimated expected cognition using multiple ELD markers to identify a subsample in the lowest quartile of expected cognition given ELD (n = 2,086). In this subsample, we estimated cross-sectional associations between personality and having above-median observed cognitive ability (n = 522) using logistic regression.
Results
Among those in the lowest quartile of expected cognition, a more internal LOC (β = 0.32 men and β = 0.44 women) and conscientious personality (β = 0.39 men and β = 0.17 women) were significantly associated with having above-median cognitive ability in models adjusted for demographic confounders. Larger benefits of conscientiousness were observed for men than women. Associations between personality and having above-median cognitive ability remained statistically significant after further adjustment for health, stress, and cognitive stimulation variables, regardless of gender.
Discussion
Personality factors may convey resilience among individuals who experienced ELD, potentially breaking the link between ELD and worse late-life cognition. Structural factors and gender roles may affect how much women benefit from personality factors.
Food insecurity remains a global public health problem. Experiencing food insecurity is related to poorer cognitive function among older adults. However, few studies have examined how food ...insecurity, experienced over the life-course, relates to cognitive function among older adults in Mexico.
Data came from the 2015 Mexican Health and Aging Study (
= 11,507 adults aged 50 and over). Early- and late-life food insecurity were ascertained by self-report. We evaluated how both measures of food insecurity related to the performance of multiple cognitive tasks (Verbal Learning, Verbal Recall, Visual Scanning, and Verbal Fluency), while controlling for key health and sociodemographic confounders using linear regression.
In descriptive analyses, respondents who experienced food insecurity in either early or late life performed significantly worse on all cognitive tasks when compared to the food secure. In models adjusted for health and sociodemographic confounders, early-life food insecurity predicted worse Verbal Learning performance and late-life food insecurity was associated with poorer Visual Scanning performance.
Food insecurity was related to poorer cognitive function in a nationally representative sample of older adults in Mexico. However, results suggested that the significance of effects depended on cognitive task and when in the life-course food insecurity was experienced.
Abstract Isla Arena is located in the coordinate 20° 70´ N - 90° 45´ W, from Campeche, Mexico. In these estuaries, the ocean mixes with fresh water, and ecosystems are concentrated where petenes and ...pink flamingos proliferate. Crustaceans and mollusks abound in the sea. Despite its enormous marine wealth, there are no studies carried out on which halophilic microorganisms are present in these waters. In this work, the diversity and structure of the microbial community was investigated through a metagenomics approach and corroborated for sequencing of 16S rRNA genes. It was found that the phylum Fimicutes predominates with more than 50%, in almost the same proportion of the class Bacilli and with almost 41% of relative abundance of the order Bacillales. The sequencing results showed that one of the samples presented a high percentage of similarity (99.75%) using the Nucleotide BLAST program with a peculiar microorganism: Bacillus subtilis. This microorganism is one of the best characterized bacteria among the gram-positive ones. Our results demonstrate that B. subtilis can be an efficient source of proteases, lipases and cellulases, from halophilic microbial communities located in poorly explored areas.
Resumo Isla Arena está localizada na coordenada 20°70’N - 90°45’W, de Campeche, México. Nesses estuários, o oceano se mistura com a água doce e os ecossistemas se concentram onde proliferam petenos e flamingos rosa. Crustáceos e moluscos abundam no mar. Apesar de sua enorme riqueza marinha, não há estudos realizados sobre a presença de microrganismos halofílicos nessas águas. Neste trabalho, a diversidade e estrutura da comunidade microbiana foram investigadas através de uma abordagem metagenômica e corroboradas para o sequenciamento de genes 16S rRNA. Verificou-se que o filo Fimicutes predomina com mais de 50%, quase na mesma proporção da classe Bacilli e com quase 41% de abundância relativa da ordem Bacillales. Os resultados do sequenciamento mostraram que uma das amostras apresentou alto percentual de similaridade (99,75%) pelo programa Nucleotide BLAST com um microrganismo peculiar: Bacillus subtilis. Nossos resultados demonstram que B. subtilis pode ser uma fonte eficiente de proteases, lipases e celulases, provenientes de comunidades microbianas halofílicas localizadas em áreas pouco exploradas.
Over the past few decades, the use of cell microencapsulation technology has been promoted for a wide range of applications as sustained drug delivery systems or as cells containing biosystems for ...regenerative medicine. However, difficulty in their preservation and storage has limited their availability to healthcare centers. Because the preservation in cryogenic temperatures poses many biological and biophysical challenges and that the technology has not been well understood, the slow cooling cryopreservation, which is the most used technique worldwide, has not given full measure of its full potential application yet. This review will discuss the different steps that should be understood and taken into account to preserve microencapsulated cells by slow freezing in a successful and simple manner. Moreover, it will review the slow freezing preservation of alginate-based microencapsulated cells and discuss some recommendations that the research community may pursue to optimize the preservation of microencapsulated cells, enabling the therapy translate from bench to the clinic.
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•Currently slow freezing represents the most appropriate storage method of microencapsulated cells.•CPA solution, sample preparation, cooling, thawing and CPA removal must be carefully selected.•Several microencapsulated cell types have been successfully cryopreserved in small volumes.•Large volumes cryopreservation of microencapsulated cells still needs optimization.
In single-isocenter stereotactic radiosurgery/radiotherapy (SRS/SRT) intracranial applications, multiple targets are being treated concurrently, often involving non-coplanar arcs, small photon beams ...and steep dose gradients. In search for more rigorous quality assurance protocols, this work presents and evaluates a novel methodology for patient-specific pre-treatment plan verification, utilizing 3D printing technology. In a patient's planning CT scan, the external contour and bone structures were segmented and 3D-printed using high-density bone-mimicking material. The resulting head phantom was filled with water while a film dosimetry insert was incorporated. Patient and phantom CT image series were fused and inspected for anatomical coherence. HUs and corresponding densities were compared in several anatomical regions within the head. Furthermore, the level of patient-to-phantom dosimetric equivalence was evaluated both computationally and experimentally. A single-isocenter multi-focal SRS treatment plan was prepared, while dose distributions were calculated on both CT image series, using identical calculation parameters. Phantom- and patient-derived dose distributions were compared in terms of isolines, DVHs, dose-volume metrics and 3D gamma index (GI) analysis. The phantom was treated as if the real patient and film measurements were compared against the patient-derived calculated dose distribution. Visual inspection of the fused CT images suggests excellent geometric similarity between phantom and patient, also confirmed using similarity indices. HUs and densities agreed within one standard deviation except for the skin (modeled as 'bone') and sinuses (water-filled). GI comparison between the calculated distributions resulted in passing rates better than 97% (1%/1 mm). DVHs and dose-volume metrics were also in satisfying agreement. In addition to serving as a feasibility proof-of-concept, experimental absolute film dosimetry verified the computational study results. GI passing rates were above 90%. Results of this work suggest that employing the presented methodology, patient-equivalent phantoms (except for the skin and sinuses areas) can be produced, enabling literally patient-specific pre-treatment plan verification in intracranial applications.
Biofilm formation by Staphylococcus aureus is a serious problem in nosocomial infections. There are great differences in the capacity of S. aureus to express biofilms, but the reasons are unknown. In ...all, 105 S. aureus strains were tested for a correlation between the agr quorum-sensing system phenotype and the ability of S. aureus to adhere to polystyrene. Some 78% of agr-negative, but only 6% of agr-positive, strains formed a biofilm, demonstrating a profound impact of agr on biofilm formation. This result was confirmed with defined agr mutants and by inhibition of agr with quorum-sensing blockers. The observed effect was not due to differential expression of the autolysin Atl or of the exopolysaccharide polysaccharide intercellular adhesin but seemed to be caused, at least in part, by the surfactant properties of δ-toxin. The detected biofilm-enhancing effect of S. aureus quorum-sensing blockers call into question the proposed therapeutic use of such substances.
In this work a first approximation to obtain non-noble metal electrocatalysts from onion skin wastes is reported. Biocarbon were obtained at a range of 600–800 °C of pyrolysis temperature activated ...by chemical treatment with HNO3. It was observed that the pyrolysis temperature has a direct effect on the structural and textural properties, besides the morphology of the onion skin waste-derived biocarbon, which shows to have influence on the catalytic activity for the oxygen reduction reaction ORR. AOB700 was the non-noble metal electrocatalyst with the best performance for the ORR evaluated in alkaline electrolyte (0.5 mol L−1 KOH), which had the highest surface area (242 m2g-1) and a current density of −2.35 mA cm−2 with an onset potential of 0.82 V/RHE. The chemical surface composition shows that N-pyridinic, N-amine, N-quaternary and N-pyrrolic nitrogen species are present on this electrocatalysts. The use of onion skin waste as raw material in the production of non-noble metal electrocatalysts is a sustainable solution to avoid the disposal of abundant biomass residues as onion skins.
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•Use as onion skin waste as potential raw material in the synthesis of as non-noble metal electrocatalysts for the ORR.•Effect of the pyrolysis temperature on the catalytic activity of onion skin-derived biocarbon towards ORR.•N-doped biocarbon as non-noble metal electrocatalyst for alkaline low temperature fuel cells.
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