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ABSTRACT Draft genomes were generated for three filamentous toxin-producing cyanobacterial strains cultivated from aquatic sources in Ohio sequenced by NovaSeq S4. Here, we report the classification and genome statistics ofPlanktothrix rubescensPR221, PR222, and PR223. 

Metagenome-assembled genomes were generated for two xenic cyanobacterial strains collected from aquatic sources in Kenya and sequenced by NovaSeq S4. Here, we report the classification and genome statistics of Microcystis panniformis WG22 and Limnospira fusiformis. 

Due to its ability to induce heterogenous, patient-specific damage in pulmonary alveoli and capillaries, COVID-19 poses challenges in defining a uniform profile to elucidate infection across all patients. Computational models that integrate changes in ventilation and perfusion with heterogeneous damage profiles offer valuable insights into the impact of COVID-19 on pulmonary health. This study aims to develop an in silico hypothesis-testing platform specifically focused on studying microvascular pulmonary perfusion in COVID-19-infected lungs. Through this platform, we explore the effects of various acinar-level pulmonary perfusion abnormalities on global lung function. Our modelling approach simulates changes in pulmonary perfusion and the resulting mismatch of ventilation and perfusion in COVID-19-afflicted lungs. Using this coupled modelling platform, we conducted multiple simulations to assess different scenarios of perfusion abnormalities in COVID-19-infected lungs. The simulation results showed an overall decrease in ventilation-perfusion (V/Q) ratio with inclusion of various types of perfusion abnormalities such as hypoperfusion with and without microangiopathy. This model serves as a foundation for comprehending and comparing the spectrum of findings associated with COVID-19 in the lung, paving the way for patient-specific modelling of microscale lung damage in emerging pulmonary pathologies like COVID-19. 

Components of the lower food web (mussels, Caridina and Omena) were collected from stations from Winam Gulf, Lake Victoria, Kenya in 2022 and 2023 to analyze for stable isotopes and total mercury (THg). Temporal comparisons were made with data generated for the same species in 1998. Values of δ15N in mussels and Caridina were similar (6.89‰ vs. 6.78 ± 0.13‰), while Omena occupied an elevated trophic position (9.97 ± 0.24‰) with minor shifts in δ15N over time. All species had elevated δ13C values in 2022–2023 versus 1998 supportive of enhanced eutrophication in the Gulf. THg concentrations exhibited modest spatial differences between sites (< 2.6 fold), but not between Caridina and Omena. Larger temporal differences were apparent relative to spatial patterns with THg concentrations decreasing in study species by 2.8 to 4.1-fold between years. An exposure assessment indicated that Omena, commonly found in local markets, can be consumed up to 0.74 kg/month without generating excess THg exposures. 

Synopsis Salt marsh ecosystems are heavily reliant on ribbed mussel (Geukensia demissa) populations to aid in rapid recovery from droughts. The focus of this study was thus to document the effects of rising temperatures on ribbed mussel populations in a Georgia salt marsh. Seven lab and eight field experiments were used to assess the effects of current air temperatures on mussels at two high marsh (HM) sites with short and sparse cordgrass and one mid marsh (MM) site with tall and dense cordgrass. Field results in 2018 and 2019 indicate that ribbed mussels were experiencing extremely high temperatures for prolonged periods of time at the landlocked high marsh (LHM) site. In 2018, the highest temperature (54°C) and longest high temperature events, HTEs (58 days), that is, consecutive days with temperatures ≥40°C, were recorded at this site. When laboratory temperatures were increased from 20 to 36°C, mean heart rates increased by an average of 19 bpm for mussels from both high and MM sites respectively. When field temperatures rose from 20°C in April to 40°C in September 2019, mean heart rates increased by an average of 10 bpm for HM mussels and by 26.3 bpm for MM mussels. Under identical laboratory and field conditions, mean heart rates for mussels from the LHM site with the highest temperatures, increased by <1 bpm and 3.7 bpm respectively. Evidence of the potential role of shade on mussel aggregates was provided by examining whether mussels from the edge of mussel aggregates with little to no cordgrass for shade were more stressed than those living at the center of mussel aggregates. In the absence of shade, mean body temperatures for mussels at the edge of mussel aggregates were up to 8°C higher than for those living in the center underneath a dense tuft of cordgrass. Despite high body temperatures, mean heart rates and Hsp70 gene expression were lower for mussels living at the edges. This agrees with the strategy that during prolong exposure to high temperatures, mussels may reduce their heart rate to conserve energy and enhance survival. Alternatively, heat-stressed mussels at the edges of aggregates may not have the resources to express high levels of Hsp70. Increase in the frequency, intensity, and duration of HTEs may stress the physiological and biochemical function of mussel populations to the limit, dictate mussel aggregate size, and threaten the functionality of SE salt marshes. 

Abstract The Winam Gulf (Kenya) is frequently impaired by cyanobacterial harmful algal blooms (cHABs) due to inadequate wastewater treatment and excess agricultural nutrient input. While phytoplankton in Lake Victoria have been characterized using morphological criteria, our aim is to identify potential toxin‐producing cyanobacteria using molecular approaches. The Gulf was sampled over two successive summer seasons, and 16S and 18S ribosomal RNA gene sequencing was performed. Additionally, key genes involved in production of cyanotoxins were examined by quantitative PCR. Bacterial communities were spatially variable, forming distinct clusters in line with regions of the Gulf. Taxa associated with diazotrophy were dominant near Homa Bay. On the eastern side, samples exhibited elevatedcyrAabundances, indicating genetic capability of cylindrospermopsin synthesis. Indeed, near the Nyando River mouth in 2022,cyrAexceeded 10 million copies L⁻¹where there were more than 6000Cylindrospermopsisspp. cells mL⁻¹. In contrast, the southwestern region had elevatedmcyEgene (microcystin synthesis) detections near Homa Bay whereMicrocystisandDolichospermumspp. were observed. These findings show that within a relatively small embayment, composition and toxin synthesis potential of cHABs can vary dramatically. This underscores the need for multifaceted management approaches and frequent cyanotoxin monitoring to reduce human health impacts.