ABSTRACT
Background: It is well knowledge that various viral illnesses may interfere with a man's ability to father children. Through the angiotensin-converting enzyme-2 receptor, which is highly concentrated in testicular tissue, the corona virus illness known as COVID-19 may cause harm to several organs. On the other hand, there is a paucity of data about the transmission of severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) in sperm, as well as the virus's influence on spermatogenesis and the capacity for fertility. We intended to look into whether or not COVID-19 guys' sperm contained SARS-CoV-2 as well as examine how COVID-19 affected the overall quality of the sperm and the degree to which it's DNA was fragmented. Material(s) and Method(s): The survey was conducted between May 2022 to October 2022, with the participation of 40 male COVID-19 patients who were between the ages of 19 and 45 and enrolled at the RSDKS, Government Medical College, Ambikapur, Chhattisgarh. We tested each sample of sperm with a real-time reverse transcriptase and found no abnormalities. At the time of the initial sample, which took place during COVID-19, a comprehensive examination of the sperm was carried out. This analysis included the calculation of the sperm DNA Fragmentation Index. After 74 days had passed since the first sample, we were able to get the second specimen and carried out the aforementioned tests once again. Result(s): All of the sperm samples that were examined using real-time reverse transcription-polymerase chain reaction (RT-PCR) came back negative for SARS-CoV-2. These samples were taken during the first and second sampling. The initial sample had considerably lower levels of fructose, semen volume, vitality, total motility, sperm concentration, total sperm count, percentage of normal morphology, and cytoplasmic droplet percentage than the subsequent samples. On the other hand, the agglutination of the semen, the percentage of head defects, the DNA Fragmentation Index, the liquefaction time, the viscosity of the semen, and the number of leukocytes all rose. At the second sample, these results were inverted, but not to the level that would be considered optimal. These results all had a p-value less than 0.05, meaning they were statistically significant. As a result, COVID-19 has a detrimental impact on the characteristics of the sperm, including the sperm DNA fragmentation index. Conclusion(s): The quality of the semen remained low up until the second time it was sampled, despite the fact that we were unable to discover SARS-CoV-2 in the sample. It is recommended that assisted reproductive technology (ART) clinics and sperm banking facilities evaluate the quality of the sperm produced by males infected with COVID-19 and exclude men who have a history of being infected with SARS-CoV-2 until the men's sperm quality recovers to normal.Copyright © 2023 Ubiquity Press. All rights reserved.
ABSTRACT
The Port of San Diego's B Street Pier facility (Pier) is the busiest cruise terminal in the City of San Diego with over a hundred ship calls annually (pre-COVID). The Pier is an approximately 9.4-acre bulkhead faced mole extending about 1,000 ft into San Diego Bay and approximately 400 ft wide. On the three offshore sides of the bulkheaded mole are marginal pile supported wharfs constructed in 1923. The upland side of the mole is a concrete gravity seawall constructed in 1900. The mole soils consist of hydraulically placed dredge spoils and are susceptible to liquefaction.The existing Pier containment walls are deemed inadequate for seismic loading, mainly due to the presence of liquefiable materials both in front of and behind the existing containment wall. A solution consisting of an improved Deep Soil Mixing (DSM) zone coupled with the installation of a new steel sheet bulkhead was selected to retrofit and upgrade the Pier to current seismic standards. A key aspect of the design was to minimize loading induced from the wharf onto the existing curtain wall during an earthquake. The DSM zone is intended to serve a triple purpose, that is to improve shear strength of the soils behind the curtain wall, to mitigate the impact of liquefaction, and to provide sufficient bearing for potential future lightly loaded structures which may be constructed on the Pier. To obtain a cost-effective design and limit the DSM zone extents, the design also needed to limit the seismic load contributions to the DSM from the marginal wharves during seismic conditions. A development plan consisting of a multi-phased construction plan was determined to meet the Port's capital improvement needs and budget. Phase I development will install the DSM zone and steel sheet pile bulkhead along the south and west face of the mole. Future work will include wharf pile and deck replacement along with completing curtain wall replacement along the north face of the mole. This paper presents the geotechnical design challenges and considerations associated with the design of the DSM and sheet pile system comprising Phase I of the development plan. Key aspects of the geotechnical design included the selection of appropriate liquefaction resistance of the DSM improved zone, designing for the lateral spread of the slope in front of the curtain wall, assessment of stability and deformation of the proposed sheet pile, and the determination of the seismic earth pressures. © ASCE.
ABSTRACT
Background: It is well knowledge that various viral illnesses may interfere with a man's ability to father children. Through the angiotensin-converting enzyme-2 receptor, which is highly concentrated in testicular tissue, the corona virus illness known as COVID-19 may cause harm to several organs. On the other hand, there is a paucity of data about the transmission of severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) in sperm, as well as the virus's influence on spermatogenesis and the capacity for fertility. We intended to look into whether or not COVID-19 guys' sperm contained SARS-CoV-2 as well as examine how COVID-19 affected the overall quality of the sperm and the degree to which it's DNA was fragmented. Material(s) and Method(s): The survey was conducted between May 2022 to October 2022, with the participation of 40 male COVID-19 patients who were between the ages of 19 and 45 and enrolled at the RSDKS, Government Medical College, Ambikapur, Chhattisgarh. We tested each sample of sperm with a real-time reverse transcriptase and found no abnormalities. At the time of the initial sample, which took place during COVID-19, a comprehensive examination of the sperm was carried out. This analysis included the calculation of the sperm DNA Fragmentation Index. After 74 days had passed since the first sample, we were able to get the second specimen and carried out the aforementioned tests once again. Result(s): All of the sperm samples that were examined using real-time reverse transcription-polymerase chain reaction (RT-PCR) came back negative for SARS-CoV-2. These samples were taken during the first and second sampling. The initial sample had considerably lower levels of fructose, semen volume, vitality, total motility, sperm concentration, total sperm count, percentage of normal morphology, and cytoplasmic droplet percentage than the subsequent samples. On the other hand, the agglutination of the semen, the percentage of head defects, the DNA Fragmentation Index, the liquefaction time, the viscosity of the semen, and the number of leukocytes all rose. At the second sample, these results were inverted, but not to the level that would be considered optimal. These results all had a p-value less than 0.05, meaning they were statistically significant. As a result, COVID-19 has a detrimental impact on the characteristics of the sperm, including the sperm DNA fragmentation index. Conclusion(s): The quality of the semen remained low up until the second time it was sampled, despite the fact that we were unable to discover SARS-CoV-2 in the sample. It is recommended that assisted reproductive technology (ART) clinics and sperm banking facilities evaluate the quality of the sperm produced by males infected with COVID-19 and exclude men who have a history of being infected with SARS-CoV-2 until the men's sperm quality recovers to normal. Copyright © 2023 Ubiquity Press. All rights reserved.
ABSTRACT
Due to the COVID-19 pandemic, personal protective waste generation has increased worldwide. Given this problem,urgent waste management methods are required to reduce waste surcharge to the environment. The present study tries to clarify the question using particle-level modeling combined with 36 undrained cyclic triaxial shear tests. The physical properties of the base materials and the face mask (FM) are first investigated and scanning electron microscopy is used to image the soil particles.This study used two kinds of sand with different median grain (D50) sizes.In doing so, shredded face mask (FM) contenthas been modifiedfrom 0 % to 1 %. In a Small silt system (fine content ≤ 40 %), liquefaction resistance decreased with silt content addition and had an opposite behavior in a Large silt system (fine content ≥ 40 %) for both sands. FM addition to silty samples leads to sustainable improvements such as more dilatative behavior and dissipation of excess pore water pressure, and enhanced liquefaction resistance. The effectiveness of FM reinforcement diminished with increasing the median grain size (D50). Also, the shear modulus of clean and silty sands improved with FM addition.
ABSTRACT
INTRODUCTION AND OBJECTIVE: SARS-CoV-2 can invade different testicular cell types, such as spermatogonia, spermatids, Sertoli, and Leydig cells. We investigated the viral presence inside the sperm of negative PCR infected men up to 3 months after discharge from the hospital. METHODS: This cross-sectional study included 13 of a 26 moderate-to-severe SARS-CoV-2 infected men cohort (mean 34.3 ± 6.5 years;range: 21-50 years old). Patients were enrolled 30 to 90 days after the diagnosis. Semen samples were obtained by masturbation and processed within one hour according to WHO guidelines. All patients were PCR negative for the virus in the ejaculate. Samples were liquefied for 30 min at room temperature in 0.1M phosphate buffer before centrifuging at 500 g for 10 min. The supernatant was removed, and pellets were fixed in 2,5% v/v glutaraldehyde in 0.1M phosphate buffer for 2h at 4°C, post-fixed in 1% OsO4 for 1h at 4°C, stained overnight in 1% aqueous uranyl acetate. Then, the pellets were dehydrated sequentially in 30%, 70%, and 100% ethanol and embedded in epoxy resin. Ultrathin sections (70nm) were obtained in an ultramicrotome, collected on nickel grids, and double-stained by uranyl acetate and lead citrate. Micrographs were obtained with a Jeol JEM 1010 electron microscope (Tokyo, Japan, 80 kV). RESULTS: We identified viruses inside spermatozoa in 9/13 patients up to 90 days after discharge from the hospital. Moreover, in all 13 men, a type of DNA-based extracellular traps, probably in a cfDNAdependent manner, like described in the COVID-19 systemic inflammatory response. FIGURE: High magnification electron micrograph of a spermatozoon with the nucleus (nu) displaying the typical condensed chromatin. The remained cytoplasm contains several viral particles (ranging in diameter from 90 to 110 nm). The inset corresponds to a higher magnification of the boxed area containing two virions, showing the SARS-CoV-2 characteristics: viral envelope (white arrowhead), nucleocapsids (black arrowhead), and spike-like projections (white arrow). CONCLUSIONS: Although SARS-CoV-2 is not found in the infected men's semen, it was intracellularly present in the spermatozoa. The potential implications for assisted conception should be addressed. (Figure Presented).
ABSTRACT
Polymers and plastics are crucial materials in many sectors of our economy, due to their numerous advantages. They also have some disadvantages, among the most important are problems with the recycling and disposal of used plastics. The recovery of waste plastics is increasing every year, but over 27% of plastics are landfilled. The rest is recycled, where, unfortunately, incineration is still the most common management method. From an economic perspective, waste management methods that lead to added-value products are most preferred—as in the case of material and chemical recycling. Since chemical recycling can be used for difficult wastes (poorly selected, contaminated), it seems to be the most effective way of managing these materials. Moreover, as a result this of kind of recycling, it is possible to obtain commercially valuable products, such as fractions for fuel composition and monomers for the reproduction of polymers. This review focuses on various liquefaction technologies as a prospective recycling method for three types of plastic waste: PE, PP and PS.
ABSTRACT
According to the forecasts made by IEA, BP, and Total in early 2021, the demand for hydrocarbons will continue for decades, and their share in the global energy balance will remain significant. Russia, as a key player in the energy market, is interested in maintaining and increasing hydrocarbon production, so further exploitation of the Arctic energy resources is an urgent issue. A large number of onshore oil and gas projects have been successfully implemented in the Arctic since the 1930s, while recently, special attention has been paid to the offshore energy resources and implementation of natural gas liquefaction projects. However, the implementation of oil and gas projects in the Arctic is characterized by a negative impact on the environment, which leads to a violation of the ecological balance in the Arctic, and affects the stability of its ecosystem, which is one of the most vulnerable ecosystems on the planet. The main goal of the present study is to understand how the implementation of oil and gas projects in the Arctic affects the ecosystem, to assess the significance of this process, and to find out what the state and business could do to minimize it. In the article, the authors analyze energy trends, provide brief information about important oil and gas projects being implemented in the Arctic region of Russia, and investigate the challenges of the oil and gas projects’ development and its negative impacts on the Arctic environment. The main contributions of this paper are the identification of all possible environmental risks and processes accompanying oil and gas production, and its qualitative analysis and recommendations for the state and business to reduce the negative impact of oil and gas projects on the Arctic ecosystem. The research methodology includes desk studies, risk management tools (such as risk analysis, registers, and maps), brainstorming, the expert method, systematization, comparative analysis, generalization, and grouping.