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Background: Pregnant women are a vulnerable population to COVID-19 given an increased susceptibility to severe SARS-CoV-2 infection and pregnancy complications. However, few SARS-CoV-2 serological surveys have been performed among this population to assess the extent of the infection in sub-Saharan countries. The objectives of this study were to determine SARS-CoV-2 seroprevalence among Beninese pregnant women, to identify spatial seropositivity clusters and to analyse factors associated with the infection. Methods: A cross-sectional study including women in their third trimester of pregnancy attending the antenatal care (ANC) clinics at Allada (south Benin) and Natitingou (north Benin) was conducted. Rapid diagnostic tests (RDT) for detection of IgG/IgM against the SARS-CoV-2 spike protein were performed using capillary blood. Seroprevalence of SARS-CoV-2 antibodies and associations between SARS-CoV-2 serostatus and maternal characteristics were analyzed by multivariate logistic regression. Spatial analyses were performed using the spatial scan statistics to identify spatial clusters of SARS-CoV-2 infection. Results: A total of 861 pregnant women were enrolled between May 4 and June 29, 2022. 58/861 (6.7%) participants reported having received COVID-19 vaccine. None of the participants had been diagnosed with COVID-19 during their pregnancy. SARS-CoV-2 antibodies were detected in 607/802 (75.7%; 95% CI 72.56%–78.62%) of unvaccinated participants. Several urban and rural spatial clusters of SARS-CoV-2 cases were identified in Allada and one urban spatial cluster was identified in Natitingou. Unvaccinated participants from Allada with at least one previous morbidity were at a three-times higher risk of presenting SARS-CoV-2 antibodies (OR = 2.89; 95%CI 1.19%-7.00%). Conclusion: Three out of four pregnant women had SARS-CoV-2 antibodies, suggesting a high virus circulation among pregnant women in Benin, while COVID-19 vaccination coverage was low. Pregnant women with comorbidities may be at increased risk of SARS-CoV-2 infection. This population should be prioritized for COVID-19 diagnosis and vaccination in order to prevent its deleterious effects. Trial registration: NCT06170320 (retrospectively registered on December 21, 2023). [ABSTRACT FROM AUTHOR]

The methodology for the optimization of the drying parameters on solar drying of copra was investigated and studied in this paper. This paper investigates the influence of the process parameters like initial mass, inclination angle and time period on the output parameters such as weight reduction rate and moisture content. Based on the analysis, optimal levels of parameters were determined and the same was validated through the confirmation test. The confirmation results reveal that, there is considerable improvement in the weight reduction rate, moisture content and grey relational grade and they improved by 37.36%, 32.28% and 32.94 % respectively. It is observed that the drying performance can be effectively improved with respect to the initial parametric setting. [ABSTRACT FROM AUTHOR]

[Display omitted] • Some invasive plant species, like Pontederia crassipes , could be possibly affected by climate change. • Megamelus scutellaris is one of the most commonly used biocontrol agents for P. crassipes. • As other planthoppers, M. scutellaris is expected to host obligate mutualistic organisms, known as Yeast-like symbiotes (YLS). • YLS are first reported in M. scutellaris species and their numbers are positively correlated with their host's weight. • YLS numbers increased under elevated CO 2 , in heavier females. Water hyacinth, Pontederia crassipes , is a highly invasive plant native to South America and one of the most invasive aquatic plants in the world. For its control, the planthopper Megamelus scutellaris Berg (Hemiptera: Delphacidae), a phloem feeder also native to South America has been introduced to the USA and South Africa. Considering predicted climate change scenarios, understanding their impacts on biological control agents is crucial. An intriguing yet scarcely explored subject, is the effect of climatic changes on the obligate endosymbionts associated with sap-sucking feeders. Planthoppers establish an obligate relationship with yeast-like symbiotes (YLS), unicellular fungal microorganisms that play an important role in their development, providing missing nutrients in their diet. Considering that increased atmospheric CO 2 affects plant chemical composition, this might have a direct impact on their insect host and on their number of YLS. We evaluated the effect of two different CO 2 environments: current (cCO 2 − 400 ppm) and elevated (eCO 2 − 800 ppm) on the abundance of YLS (number of YLS cells/insect) of M. scutellaris , as well as the, age structure, sex, and weight of insects. Heavier females harbored more YLS under eCO 2 which underscores the importance of the interaction of CO 2 levels and insects' weight in shaping the abundance of YLS. Additionally, there was a significant increase in the total abundance of insects for instars III to V and adults under eCO 2 conditions. However, male number significantly exceeded that of females under both CO 2 conditions. Our results suggest a potential positive impact of eCO 2 on M. scutellaris populations, which could, in turn, enhance the control of P. crassipes. [ABSTRACT FROM AUTHOR]

Background: Phospholipids are important structural and signaling molecules in plant membranes. Some fluorescent dyes can stain general lipids of membranes, but labeling and visualization of specific lipid classes have yet to be developed for most components of the membrane. New techniques for visualizing membrane lipids are needed to further delineate their dynamic structural and signaling roles in plant cells. In this study we examined whether propargylcholine, a bioortholog of choline, can be used to label the major membrane lipid, phosphatidylcholine, and other choline phospholipids in plants. We established that propargylcholine is readily taken up by roots, and that its incorporation is not detrimental to plant growth. After plant tissue is harvested and fixed, a click-chemistry reaction covalently links the alkyne group of propargylcholine to a fluorescently-tagged azide, resulting in specific labeling of choline phospholipids. Results: Uptake of propargylcholine, followed by click chemistry with fluorescein or Alexa Fluor 594 azide was used to visualize choline phospholipids in cells of root, leaf, stem, silique and seed tissues from Arabidopsis thaliana. Co-localization with various subcellular markers indicated coinciding fluorescent signals in cell membranes, such as the tonoplast and the ER. Among different cell types in the leaf epidermis, guard cells displayed strong labeling. Mass spectrometry-based lipidomic analysis of the various plant tissues revealed that incorporation of propargylcholine was strongest in roots with approximately 50% of total choline phospholipids being labeled, but it was also incorporated in the other tissues including seeds. Phospholipid profiling confirmed that, in each tissue analyzed, incorporation of the bioortholog had little impact on the pool of choline plus choline-like phospholipids or other lipid species. Conclusion: We developed and validated a click-chemistry based method for fluorescence imaging of choline phospholipids using a bioortholog of choline, propargylcholine, in various cell-types and tissues from Arabidopsis. This click-chemistry method provides a direct way to metabolically tag and visualize specific lipid molecules in plant cells. This work paves the way for future studies addressing in situ localization of specific lipids in plants. [ABSTRACT FROM AUTHOR]

Glucosylceramides (GlcCer), glucose-conjugated sphingolipids, are major components of the endomembrane system and plasma membrane in most eukaryotic cells. Yet the quantitative significance and cellular functions of GlcCer are not well characterized in plants and other multi-organ eukaryotes. To address this, we examined Arabidopsis lines that were lacking or deficient in GlcCer by insertional disruption or by RNA interference ( RNAi) suppression of the single gene for GlcCer synthase ( GCS, At2g19880), the enzyme that catalyzes GlcCer synthesis. Null mutants for GCS (designated ' gcs-1') were viable as seedlings, albeit strongly reduced in size, and failed to develop beyond the seedling stage. Heterozygous plants harboring the insertion allele exhibited reduced transmission through the male gametophyte. Undifferentiated calli generated from gcs-1 seedlings and lacking GlcCer proliferated in a manner similar to calli from wild-type plants. However, gcs-1 calli, in contrast to wild-type calli, were unable to develop organs on differentiation media. Consistent with a role for GlcCer in organ-specific cell differentiation, calli from gcs-1 mutants formed roots and leaves on media supplemented with the glucosylated sphingosine glucopsychosine, which was readily converted to GlcCer independent of GCS. Underlying these phenotypes, gcs-1 cells had altered Golgi morphology and fewer cisternae per Golgi apparatus relative to wild-type cells, indicative of protein trafficking defects. Despite seedling lethality in the null mutant, GCS RNAi suppression lines with ≤2% of wild-type GlcCer levels were viable and fertile. Collectively, these results indicate that GlcCer are essential for cell-type differentiation and organogenesis, and plant cells produce amounts of GlcCer in excess of that required for normal development. [ABSTRACT FROM AUTHOR]