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Safe and effective vaccines became an important preventive tool against novel corona virus disease infection. Physicians were prioritized for early vaccination since they are at higher risk for contagion of the infection and they might affect the general populations’ uptake of the vaccine. This study aimed to examine the acceptability of COVID-19 vaccines and the underpinnings of reluctance to uptake the vaccine among working physicians in Egypt. A cross-sectional study was conducted for 3 months, recruiting 1268 physicians using a snowballing random sampling technique. A self-administered electronic questionnaire was deployed to collect related data. Of participants, 24% expressed their acceptance towards COVID-19 vaccines, 39% would wait for further review, while 36.7% did not agree to get vaccinated. Findings revealed that 22% of them were vaccinated and the significant determinants of unacceptability included age, gender, higher educational attainments, prior infection, lack of direct patients’ contact, and working in rural health facilities (p < 0.05). The most common reasons beyond their reluctance were fear of the vaccines’ adverse effects and the short duration of its clinical trials (60% and 49.5%). Physicians had a low intention to receive COVID-19 vaccines particularly between females, senior staff, and those who had a low self-perceived risk for the infection. Integrated approaches should be designed to address concerns and factors associated with vaccine unacceptability to reduce vaccination reluctance between physicians, hence the general population.

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The results of this study indicate that the optimum solids concentrations for anaerobic digestion of poultry waste was 8% at incubation temperatures of 22 and 37 °C. Changes in the temperature of the digestion affected the total volume of biogas produced, its rate of production, and the time required for the digestion. Algal production on the digested effluent was a successful process, producing high biomass content. The bacteriological quality of raw and digested waste, as well waste during algal culture, reflects the possible health risks which may occur with the use of anaerobically digested sludge with or without treatment.  相似文献   
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The effect of Bladex, Etazine, Dicryl, and Baylucide on the growth of the fresh water alga Scenedesmus was investigated. The alga was cultured in various concentrations of the above mentioned pesticides. Scenedesmus was found to be more resistant to Dicryl than to the three other compounds. Dicryl, at a concentration of 2 mg/L, did not lead to complete inhibition of Scenedesmus cells. On the other hand, Bladex, Etazine and Baylucide, at a concentration of 0.5 mg/L, could eliminate the alga from cultures. Examination of Scenedesmus in all testing cultures showed that marked morphological changes and chloroplast disruption occurred especially in the presence of high concentrations of the studied compounds.  相似文献   
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Environmental Science and Pollution Research - Campylobacter, Gram-negative bacteria, is the most common cause of acute bacterial enteritis in human beings, both in developing and developed...  相似文献   
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The fresh water alga Scenedesmus was cultured in graded concentration of Cu, Cd, Ni, Zn, and Pb to evaluate the effect of these cations on the growth response of Scenedesmus. The effective concentration of metal which depressed the Scenedesmus growth for Cu was 0.5 mg l−1, for Cd 0.5 mg l−1, for Ni 2 mg l−1, and for Zn 2 mg l−1. The alga exhibited tolerance for high Pb concentrations up to 30 mg l−1. Exposure of a Scenedesmus cell to each metal revealed anatomical changes and chloroplast disruption especially at high metal concentrations.  相似文献   
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Changes of phytoplankton density and their relation to physicochemical characteristics along the Nile River have been noted in the Cairo district between 1976 and 1982. Three major phytoplankton groups were found to dominate the river Nile: green algae, blue-green algae, and diatoms. Diatoms represent the most dominant group and comprised from 42% to 96% of the phytoplankton community during the investigated period. Blue-green algae comprised from 0.7% to 48% of total cell number. Green algae represent the low percentage group, which ranges from 0.2% to 41% of Nile water algae. High species diversity (H′) was detected in green algae (1.22) followed by diatoms (0.84); the lowest diversity was in blue-green algae (0.45). The density of total phytoplankton count fluctuated between 106 and 107 organism/L. The concentration of chlorophyll-a ranged from 5 to 37 mg/m3. Primary production rates in the Nile River ranged from 8.5 to 52 mg O2/m3h. Statistical analysis revealed significant positive correlations between chlorophyll-a content, and concentrations of phosphoruss and nitrate. Phytoplankton diversity, primary production, ammonia, and nitrite content revealed that there is no indication of pollution in the Nile.  相似文献   
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Selenium and nano-selenium in plant nutrition   总被引:1,自引:0,他引:1  
Selenium (Se) is a naturally occurring metalloid element which occurs nearly in all environments. Se is considered as a finite and non-renewable resource on the Earth. The common sources of Se in earth’s crust occur in association with sulfide minerals such as metal selenide, whereas it is rarely found in elemental form (Se0). While there is no evidence of Se need for higher plants, several reports show that when Se added at low concentrations, Se exerts beneficial effects on plant growth. Se may act as quasi-essential micronutrient through altering different physiological and biochemical traits. Thus, plants vary considerably in their physiological and biochemical response to Se. This review focusses on the physiological importance of Se forms as well as different Se fertilizers for higher plants, especially plant growth, uptake, transport, and metabolism.  相似文献   
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Abstract

Studies were conducted to determine the metabolic fate of chloramphenicol (CAP) in White Leghorn using the l4C‐labelled compound. In one experiment birds were administered orally via intra‐crop, a single dose of 100 mg (equivalent to 66 mg kg‐1 body weight) of CAP containing 14 μCi 14C‐CAP, and its absorption, elimination and distribution in plasma were recorded. Orally dosed 14C‐compound was rapidly absorbed, efficiently distributed in plasma and eliminated in excreta (>70% in 5 hr). After 5 h, CAP equivalent residues in tissues were lower than 15 μg g‐1 for this treatment. In a second experiment birds were given intra‐crop dose of either 0.5 or 5 mg of CAP (each dose contained 2.5 μCi 14C‐CAP) daily for five consecutive days followed by a seven day withdrawal period and elimination of 14C in excreta and eggs was monitored. More than 95% of the administered 14C was eliminated within the first 24 h after dosing. Radiocarbon (14C) was deposited preferentially in yolks compared to albumen or other tissues. Residues declined when feeding was stopped. Various metabolites were isolated and identified by a combination of TLC, LC, and LC‐MS. The main metabolic route of CAP in laying hens appears to be the glucuronidation. Cleavage of the dichloroacetate moiety was only a minor route.  相似文献   
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