Abstract:The paper presents the characterization of bimetallic bearings as mechanical testing and SEM analysis. Also, a proper simplified structure of the horizontal centrifugal casting mechanism is applied, which uses a high-frequency current for the heat of bimetallic bearings from steel-bronze. The chemical stability treatment of the borderline alloy layer at the interference of internal cylindrical steel surface and external bronze surface by adding into Cu-Sn filler a supplier non-ferrous metal was performed. The experiment results have shown that the bimetallic bearings of steel-bronze achieved good physical properties and adhesion between antifriction steel with bronze that validated this simplified structure of the horizontal centrifugal casting process.
Abstract:Background: Sources of variation in laboratory results can be pre-analytical, analytical and biological. Biological sources of variation are often used as factors for stratifying reference intervals. The aim of the study is to investigate the seasonal variation in red blood cells (RBCs), RBC indexes (MCV – mean cell volume; MCH mean cell hemoglobin and MCHC - mean hemoglobin concentration in erythrocytes), haemoglobin (Hgb) and platelet counts (Plts) within reference limits and its dependence on sex and age.\nMaterial and methods: The research was carried out in UH St. Ivan Rilski, Sofia, for one year period (January - December 2022). Results outside the reference intervals are excluded. The following parameters are evaluated: RBCs, RBC indexes and Hgb in 13,197 men and 18,729 women, and Plts in 18,125 men and 21,018 women. Alinity hq, Abbott haematological analyser is used. \nResults: RBC and Hgb levels are higher in males (+9% and 11%, respectively). In women, a higher level of Plts is found with approximately 5%. It is observed a winter (November and December) decrease in RBC (in men - 5.8% and in women - 4.6%) and an increase in Plts in December - in women with + 4.2% and in men with + 3% compared to summer. Hgb increases slightly from August to December +2.7% for men and women. Gradually from September to December, MCH, MCHC and MCV are increasing in both sexes. \nConclusion: The changes in the studied hematological indicators provide an evidence that these fluctuations are not random but related to the seasons. Sex and age differences are also observed in the present study with no alteration in the seasonal variation.
Abstract:2nd International Conference on Computational and Applied Physics, ICCAP\'2023
Abstract:Natural disasters can hamper development plans in food commodity development. There are many disaster-prone areas that need efforts to reduce the risks that occur from these disasters. The purpose of this study was to analyze the determinants of resilience of households of wet-rice farmers affected by flooding. This research uses a quantitative analysis approach with survey method. The research data were collected through primary and secondary data. The respondent sampling technique used multi-stage cluster random sampling with a total of 306 respondents. The results showed that mitigation, adaptation, coping mechanisms, and risk levels had a significant influence on the resilience model of households of flood-affected wetland rice farmers. Based on these results, this research can be a reference for practitioners in increasing the intention of resilience actions against natural disasters that occur. Furthermore, the need for policies from the government to respond to natural disasters so that they do not have a long impact on the continuity of farming that is managed.
Abstract:Agricultural waste biomass has already been transferred to bioethanol and used as energy related products, although many issues such as efficiency and productivity still exist to be overcome. In this chapter, the protein engineering was applied to generate enzymes with completely reversed coenzyme specificity and developed recombinant yeasts containing those engineered enzymes for construction of an efficient biomass-ethanol conversion system. Recombinant yeasts were constructed with the genes encoding a wild type xylose reductase (XR) and the protein engineered xylitol dehydrogenase (XDH) (with NADP) of Pichia stipitis. These recombinant yeasts were characterized based on the enzyme activity and fermentation ability of xylose to ethanol. The protein engineered enzymes were expressed significantly in Saccharomyces cerevisiae as judged by the enzyme activity in vitro. Ethanol fermentation was measured in batch culture under anaerobic conditions. The significant enhancement was found in Y-ARS strain, in which NADP+-dependent XDH was expressed; 85% decrease of unfavorable xylitol excretion with 26% increased ethanol production, when compared with the reference strain expressing the wild–type XDH.
Abstract:Finding sustainable solutions for the present global energy needs compels us to look after renewable energy resources. Conventional electronic technologies utilizing these resources offer obvious disadvantages such as low biocompatibility and biodegradability. Materials possessing biocompatibility, biodegradability, and low toxicity with increased performance are sought after by researchers in the field of organic electronics. The recent emergence of �Green electronics� indicates this shift in the field. The potential of many biomaterials for organic electronics applications has been realized fairly thoroughly. Out of these Humic Substances forming a significant part of biomass are relatively unexplored for applications in electronic devices. A large literature exists which explains their chemical, biological and geologicalproperties with applications in the field of agriculture and bio-medicine. However, research on their potential for electronic device applications has been comparatively low. Some of the recent investigations on humic substances, particularly on humic acids, reveal them to be a suitable candidate for the fabrication of a variety of electronic devices (Batteries, Supercapacitors, Solar Cells etc.). Easy availability, low-cost production, and environmental friendliness further add to their suitability. In the present review, we have discussed in briefvarious important aspects of humic substances (chemical, electrical and optical) and attempted to put forth the role these substances could play in electronic device making. A survey of past research work on humic substances-based electronic devices is also presented. Furthermore, from a futuristic viewpoint, potential areas of investigation (e.g., Ferroelectricity,Supramolecular electronics etc.) have been touched upon.
Abstract:Pereskia bleo, belongs to the Cactaceae family has been traditionally used for treating various diseases. This study aimed to determine the phytochemical analysis, antibacterial activity, antioxidant activity, total phenolic content, and total flavonoid content of Pereskia bleo flowers. Phytochemical screening revealed the presence of glycoside, alkaloid, flavonoid, saponin, tannin, steroid, and terpenoid. The antioxidant activity test indicated that the crude extract of Pereskia bleo flowers had an average IC50 value of 6 ± 0.4359, confirming positive results in the phenolic content test. The total phenolic content of the Pereskia bleo flower crude extract was calculated as 75.295 mg/g at a concentration of 15.059 μg/ml and absorbance of 0.165. In contrast, the calculated total flavonoid content was 7.385 mg/g at a concentration of 9.477 μg/ml, suggesting the present of flavonoid compounds in the flowers of Pereskia bleo. The antibacterial activity of this sample was also tested using the disc-diffusion method against Gram-negative (Salmonella sp., Pseudomonas sp., E. coli) and Gram-positive (Staphylococcus aureus, Bacillus sp., Staphylococcus epidermidis) bacterial strains. The collected data showed that both 100 μg/ml and 500 μg/ml sample concentrations exhibited potent activity against Salmonella sp. and Pseudomonas sp.
Abstract:The study \"Bankruptcy Forecast Analysis in the Manufacturing Subsector of Norte de Santander, Colombia (2015 – 2022)\" offers an empirical evaluation of financial stability in this region, using the capital structure theory of Modigliani and Miller and the Altman Z-Score model for bankruptcy risks as a theoretical foundation. Through a quantitative approach that includes time series analysis, the internal and external factors that affect the financial competitiveness of the subsector are analyzed. The research highlights the contributions and limitations of capital structure theory and the Z-Score model in real practices, and discusses the integration of advanced technologies such as artificial intelligence to fine-tune financial risk predictions. Using purposeful sampling and documentary analysis, patterns are identified and business solvency is assessed, providing a detailed view of the sector\'s resilience in the face of economic challenges. This study provides valuable insights for those interested in the financial sustainability of the manufacturing sector, highlighting the importance of adapting risk management strategies to regional particularities. Its contribution to the specialized literature lies in offering an updated perspective on bankruptcy forecasting and financial management adapted to the specific context of the Colombian emerging economy.
Abstract:Species distribution modeling has become a very popular tool for anticipation and decision-making in biological resource conservation. This study aims to assess changes in the future distribution of Brachytrupes membranaceus habitats in Kinshasa between 2055 and 2100.\nThree variables contributed most to the model: rainfall in the driest month (38.4%), soil (28.9%) and rainfall in the coldest quarter (13.9%). Currently, 89.3% of Kinshasa\'s surface area is highly favorable to the development and conservation of B. membranaceus, compared with 69.5% and 47.5% in 2055 (optimistic and pessimistic scenarios respectively) and 61.5% and 39.2% in 2100 (optimistic and pessimistic scenarios respectively), mainly in the urban zone. From the current to the future climate, the areas potentially favorable to the development and conservation of B. membranaceus shift from the periphery to the urban center of Kinshasa (for all scenarios for the years 2055 and 2100).\nThis shows that threats to the development and conservation of B. membranaceus are mainly due to anthropogenic activities (anarchic construction and slash-and-burn agriculture) and less to climatic/environmental factors (rainfall and soil). These results contribute to Sustainable Development Goals 11 and 15 by 2030.
Abstract:Cyanobacteria had taken 2.7 billion years to change O2 content to a habitable level on the Earth. In terraforming Mars, producing O2 and food, and creating a tolerable radiation are challenging. Here, we argue that, with the available advancements of science today and perhaps in years to come, the maximum, humans would be able to do on Mars in the future is to live inside a chamber with controlled conditions. But, no one would be able to be a real Martian who can walk freely on Mars soil. Thinking outside the box, there is a great possibility for us to do that by getting ourselves changed a little bit to be adaptable to Martian conditions, which is much more achievable than changing a whole planet. Here, we suggest that by being photoautotrophic humans, like the spotted salamander, and having the ability to tolerate radiation, we would be able to be real Martians.