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There are over 50 SARS-CoV-2 candidate vaccines undergoing Phase II and III clinical trials. Several vaccines have been approved by regulatory authorities and rolled out for use in different countries. Due to concerns of potential teratogenicity or adverse effect on maternal physiology, pregnancy has been a specific exclusion criterion for most vaccine trials with only two trials not excluding pregnant women. Thus, other than limited animal studies, gradually emerging development and reproductive toxicity data, and observational data from vaccine registries, there is a paucity of reliable information to guide recommendations for the safe vaccination of pregnant women. Pregnancy is a risk factor for severe COVID-19, especially in women with comorbidities, resulting in increased rates of preterm birth and maternal morbidity. We discuss the major SARS-CoV-2 vaccines, their mechanisms of action, efficacy, safety profile and possible benefits to the maternal-fetal dyad to create a rational approach towards maternal vaccination while anticipating and mitigating vaccine-related complications. Pregnant women with high exposure risks or co-morbidities predisposing to severe COVID-19 infection should be prioritised for vaccination. Those with risk factors for adverse effects should be counselled accordingly. It is essential to support patient autonomy by shared decision-making involving a risk-benefit discussion with the pregnant woman.  相似文献   
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Abstract

Glyphosate, which is commercially available as Roundup®, was the widely used herbicide in Sri Lanka until 2015 and is suspected to be one of the causal factors for Chronic Kidney Disease of unknown etiology (CKDu). This research, therefore, aims at studying the presence of glyphosate and Aminomethylphosphonic acid (AMPA) in different environmental matrices in CKDu prevalent areas. Topsoil samples from agricultural fields, water samples from nearby shallow wells and lakes, and sediment samples from lakes were collected and analyzed for glyphosate and AMPA using the LC/MS. Glyphosate (270–690 µg/kg) and AMPA (2–8 µg/kg) were detected in all soil samples. Amorphous iron oxides and organic matter content of topsoil showed a strong and a moderate positive linear relationship with glyphosate. The glyphosate and inorganic phosphate levels in topsoil had a strong negative significant linear relationship. Presence of high valence cations such as Fe3+ and Al3+ in topsoil resulted in the formation of glyphosate-metal complexes, thus strong retention of glyphosate in soil. Lower levels of AMPA than the corresponding glyphosate levels in topsoil could be attributed to factors such as the strong adsorption capacity of glyphosate to soil and higher LOQ in the quantification of AMPA. The glyphosate levels of lakes were between 28 to 45 µg/L; no AMPA was detected. While trace levels of glyphosate (1–4 µg/L) were detected in all groundwater samples, AMPA (2–11µg/L) was detected only in four out of nine samples. Glyphosate was detected in all sediment samples (85–1000 µg/kg), and a strong linear relationship with the organic matter content was observed. AMPA was detected (1–15 µg/kg) in seven out of nine sediment samples. It could be inferred that the impact on CKDu by the levels of glyphosate and AMPA detected in the study area is marginal when compared with the MCL of the USEPA (700 µg/L).  相似文献   
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There remain unanswered questions concerning mother-to-child-transmission of SARS-CoV-2. Despite reports of neonatal COVID-19, SARS-CoV-2 has not been consistently isolated in perinatal samples, thus definitive proof of transplacental infection is still lacking. To address these questions, we assessed investigative tools used to confirm maternal-fetal infection and known protective mechanisms of the placental barrier that prevent transplacental pathogen migration. Forty studies of COVID-19 pregnancies reviewed suggest a lack of consensus on diagnostic strategy for congenital infection. Although real-time polymerase chain reaction of neonatal swabs was universally performed, a wide range of clinical samples was screened including vaginal secretions (22.5%), amniotic fluid (35%), breast milk (22.5%) and umbilical cord blood. Neonatal COVID-19 was reported in eight studies, two of which were based on the detection of SARS-CoV-2 IgM in neonatal blood. Histological examination demonstrated sparse viral particles, vascular malperfusion and inflammation in the placenta from pregnant women with COVID-19. The paucity of placental co-expression of ACE-2 and TMPRSS2, two receptors involved in cytoplasmic entry of SARS-CoV-2, may explain its relative insensitivity to transplacental infection. Viral interactions may utilise membrane receptors other than ACE-2 thus, tissue susceptibility may be broader than currently known. Further spatial-temporal studies are needed to determine the true potential for transplacental migration.  相似文献   
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Poly(hydroxybutyrate-co-valerate) (PHBV) is a completely biodegradable thermoplastic polyester produced by microbial fermentation. The current market price of PHBV is significantly higher than that of commodity plastics such as polyethylene and polystyrene. It is therefore desirable to develop low-cost PHBV based materials to improve market opportunities for PHBV. We have produced low-cost environmentally compatible materials by blending PHBV with granular starch and environmentally benign CaCO3. Such materials can be used for specific applications where product biodegradability is a key factor and where certain mechanical properties can be compromised at the expense of lower cost. The inclusion of granular starch (25 wt%) and CaCO3 (10 wt%) in a PHBV matrix (8% HV, 5% plasticizer) reduces the cost by approximately 40% and has a tensile strength of 16 MPa and flexural modulus of 2.0 Gpa, while the unfilled PHBV/plasticizer matrix has a tensile strength of 27 MPa and a flexural modulus of 1.6 GPa.Paper presented at the Bio/Environmentally Degradable Polymer Society—Third National Meeting, June 6–8, 1994, Boston, Massachusetts.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.  相似文献   
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The carbon monoxide (CO) and particulate matter (PM) emissions of woodburning stoves have been measured under field conditions. Both conventional airtight stoves and newly installed airtight stoves certified by the U.S. Environmental Protection Agency to be low emitters of PM were monitored. The certified stoves were of two types, catalytic and noncatalytic. Compared to the conventional stoves, PM emission rates (g/hr) were reduced approximately 70% by both types of certified stoves. The CO emission rates were reduced 71% and 53% by catalytic and noncatalytic stoves respectively. These rate reductions occur because the certified stoves burn cleaner (less pollutant formation per kg of wood burned) and the average burn rate of certified stoves in field use is less than the average burn rate of conventional stoves.  相似文献   
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Environmental Science and Pollution Research - Development of satellite technology over decades established unique approach to analyze rice crop phenological parameters and supervise growth and...  相似文献   
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Common property resources are areas of land or water being used by a community or a group of communities. These have special significance to peoples and communities who depend on them for their livelihood. The commons in all arid districts of India include village pastures, community forests, wasteland, common threshing grounds, waste dumps, watershed drainage, village baoris1, talabs2, nadis3 and ponds, and tanks, rivers, rivulets, wetlands, riverbeds, community conserved areas, protected areas, Dhaam4 or Dhooni5, culturable wastelands, barren & un-culturable land, etc. The area under commons often ranged from 9 to 28% of total village area. Appropriation of the commons by the state for building essential infrastructure such as schools, clinics, veterinary hospitals, housing for government functionaries, SEZ and industrial corridors, etc. is a cause of serious concern. Presently the ownership rights over CPRs are not clear and there are many who claim ownership, some at State level but also like local bodies. The 12th plan of the Planning Commission of India recognized and highlighted the need for favourable land tenure arrangements, institutional design and programme architecture in order to achieve effective governance and management of the commons. The revitalization of CPRs is crucial for protecting livelihoods, as well as for biodiversity conservation and for the improvement in arid microclimatic conditions. Dialogue continues on the status of common property resources, the available legal framework and some policy related issues for its conservation through strengthening of local institutions and capacity building for stakeholders.  相似文献   
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