The impact of UV-B radiation (UVBR; 280-320 nm) on lower levels of a natural plankton assemblage (bacteria, phytoplankton and microzooplankton) from the St. Lawrence Estuary was studied during 9 days using several immersed outdoor mesocosms. Two exposure treatments were used in triplicate mesocosms: natural UVBR (N treatment, considered as the control treatment) and lamp-enhanced UVBR (H treatment, simulating 60% depletion of the ozone layer). A phytoplankton bloom developed after day 3, but no significant differences were found between treatments during the entire experiment for phytoplankton biomass (chlorophyll a and cell carbon) nor for phytoplankton cell abundances from flow cytometry and optical microscopy of three phytoplankton size classes (picoplankton, nanoplankton and microplankton). In contrast, bacterial abundances showed significantly higher values in the H treatment, attributed to a decrease in predation pressure due to a dramatic reduction in ciliate biomass (approximately 70-80%) in the H treatment relative to the N treatment. The most abundant ciliate species were Strombidinium sp., Prorodon ovum and Tintinnopsis sp.; all showed significantly lower abundances under the H treatment. P. ovum was the less-affected species (50% reduction in the H treatment compared with that of the N control), contrasting with approximately 90% for the other ones. Total specific phytoplanktonic and bacterial production were not affected by enhanced UVBR. However, both the ratio of primary to bacterial biomass and production decreased markedly under the H treatment. In contrast, the ratio of phytoplankton to bacterial plus ciliate carbon biomass showed an opposite trend than the previous results, with higher values in the H treatment at the end of the experiment. These results are explained by the changes in the ciliate biomass and suggest that UVBR can alter the structure of the lower levels of the planktonic community by selectively affecting key species. On the other hand, linearity between particulate organic carbon (POC) and estimated planktonic carbon was lost during the postbloom period in both treatments. On the basis of previous studies, our results can be attributed to the aggregation of carbon released by cells to the water column in the form of transparent exopolymer particles (TEPs) under nutrient limiting conditions. Unexpectedly, POC during such a period was higher in the H treatment than in controls. We hypothesize a decrease in the ingestion of TEPs by ciliates, in coincidence with increased DOC release by phytoplankton cells under enhanced UVBR. The consequences of such results for the carbon cycle in the ocean are discussed.
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http://dx.doi.org/10.1562/2006-02-23-ra-810 | DOI Listing |
Afr J Reprod Health
December 2024
Department of Obstetrics and Gynecology, Changshu Hospital Affiliated to Nanjing University of Chinese Medicine,Changshu 215500, Jiang Su,China.
The study was designed to appraise the effects of early antibiotic administration on reproductive tract infections and fetal membrane cell scorching in instances of premature rupture of membranes (PROM). A total of 107 pregnant women diagnosed with PROM between July 2020 and June 2022 were randomly assigned to two groups: the Intervention (n=54), where ampicillin were administered within 24 hours of PROM onset, and the control group (n=53), where ampicillin were given 24-48 hours after PROM. Maternal and neonatal outcomes, incidence of reproductive tract infections, and fetal membrane cell scorching indicators (Caspase-1, Caspase -3, Caspase-9 and IL-β) were compared.
View Article and Find Full Text PDFAfr J Reprod Health
December 2024
Department of Gynecology and Obstetrics, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, Jiangsu, China.
Through implementing a bidirectional Mendelian randomization (MR) study, the causal effects between gut microbiome and polycystic ovary syndrome (PCOS) were analyzed. Summary statistics for PCOS were acquired from the FinnGen consortium R8 release data, which included 27,943 cases and 162,936 controls. The inverse-variance weighting (IVW) method was adopted for analysis.
View Article and Find Full Text PDFAfr J Reprod Health
December 2024
Department of Obstetrics and Gynecology, Nanjing Drum Tower Hospital, Affiliated Hospital of Nanjing University Medical School, Nanjing , China.
Giant ovarian cysts (GOCs) have become less common in developed countries due to routine health screenings, but they remain prevalent in economically underdeveloped regions. Treatment options for GOCs depend on factors such as age, cyst characteristics, and pregnancy status. Minimally invasive single-port laparoscopic surgery has largely replaced traditional open surgery due to its aesthetic advantages and effectiveness.
View Article and Find Full Text PDFAfr J Reprod Health
December 2024
Department of Mammary gland, The First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine), Zhejiang, 310006.
This study sought to compare bacterial abundance and diversity in milk and feces of healthy lactating women with patients suffering from lactation mastitis, explore the pathogenesis of lactation mastitis, and develop new ideas for its treatment and prevention from a microbiological perspective. A total of 19 lactating mastitis patients and 19 healthy lactating women were recruited. Milk and fecal Specimens were obtained from both groups, and microbial community structure was analyzed using 16S rRNA gene sequencing.
View Article and Find Full Text PDFPsychiatry Clin Psychopharmacol
December 2024
Sleep and Disorders Unit, Division of Clinical Neurophysiology, Department of Neurology, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, İstanbul, Türkiye.
Background: Weighted blankets have recently introduced in the treatment on insomnia as a nonpharmacological integrative therapy. Here we prospectively evaluated the effects of weighted blankets on the sleep structure and heart rate variability (HRV) in patients with primary psychophysiological insomnia.
Methods: In this prospective polysomnographic (PSG) study between August 2021 and August 2022, patients were given weighted blankets (~10% of body weight) to use at home for 10 nights consecutively.
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