bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural and modal analysis in solidworks of agricultural plow to choose vibration system at moldboard
Authors: Gheorghe Gabriel , Lates Daniel , Oprea Claudiu , Baltatu Carmen
Published: June 2023

This article presents the way to obtain the structural model for elementary linear-elastic static analysis of the moldboard of the plow. Also, to prove the functionality of the structural model obtained, the structural analysis results for the linear elastic static test are presented. These results are useful for estimating the safety factor and for assessing the behavior in major overstress situations at the main part of the machine. Structure dynamics is a very broad discipline that uses a huge arsenal of theoretical and experimental methods to solve the fundamental problem of structures: the dynamic response to variable tasks over time. Vibrations, and especially vibration in resonance modes, are problems that occur frequently in large structures. As large structures with large numbers of components cannot be optimally engineered for resonant regimes, it is often done to resolve structures or improve them by using the modal analysis of the mathematical models of these structures. The usefulness of this analysis is particularly evident in the testing phase and even in the first stages of operation when it is necessary to improve the working regime of a product of the type analyzed. The main results of the static linear-elastic structural analysis are the values of the reactions in the holders, vector field distribution of the relative – resultant displacement in the structure, tensor fields’ distribution of the specific deformation and the Cauchy stress tensor in the same structure. Also, an important result for structure safety is the distribution of the safety factor. The analysis of the equipment’s own spectrum allows proper identification of the main frequencies, at which a resonant working regime can occur as well as the necessary forces to choose the optimal vibration system.
Research on yield of biogas during methane fermentation of cow manure with addition of granulated straw with slaked lime
Authors: Valiev Timur , Polishchuk Viktor
Published: June 2023

Cattle manure is often used to produce biogas, from which electricity and heat are generated. However, due to presence of a large amount of crude fiber in manure, the yield of biogas when it is fermented using biogas plants is relatively low. Therefore, an urgent task is to increase the yield of biogas from cattle manure through the use of various additives stimulating methane fermentation. Polyethylene bags were used as digesters, which were sealed with special devices. A calibrated cylinder was used to determine the biogas yield. The acidity of the substrate was measured with a pH meter. The novelty of the chosen topic lies in the use of chemical processing of biomass in combination with extrusion. The research results showed that pretreatment of wheat straw with different concentrations of Ca(OH)2 leads to the breakdown of lignocellulose, an increase in biogas yield and electricity generation. The optimal loading at rate of 100 kg CaO(t-1 into the reactor in the form of straw pellets has significant advantages and is the optimal solution, since the biogas yield in this case is practically the same as the yield obtained from wheat straw pellets at the rate of 150 kg CaO(t-1 of straw, but it is more cost effective. In addition, the year round use of straw pellets with the optimal addition of slaked lime for a biogas plant makes it possible to obtain high quality biological organic fertilizers; ensure high stable and trouble-free operation of the entire system as a whole; to increase gas recovery from bioraw materials of plant origin due to the decomposition of cellulose. This makes it easier to switch to other types of raw materials, and also increases the specific load of the entire line. It can be seen from the calculations that the highest methane yield (0.342 m3(kg-1 of dry matter) was obtained from wheat straw pellets, which were processed after extrusion with a Ca(OH)2 solution at rate of 100 kg CaO(t-1, 40% more than the control experiment.
Multi-criteria approaches for choosing intermodal technology for container transportation
Authors: Stoilova Svetla
Published: June 2023

In this study integrated multi-criteria approaches are developed based on the Shannon entropy method and multi-criteria analysis for the study of intermodal transport. The research methodology consists of the following steps: definition of criteria; determination of alternatives; determination of criteria weights by the Shannon’s entropy method; ranking the alternatives by applying multi-criteria approaches; verification of the results. The Shannon’s entropy method allows to determine the weights of the criteria in a mathematical way without using expert evaluation. The multicriteria methods – Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), Complex Proportional Assessment method (COPRAS), Compromise Programming (CP) and Preference Ranking Organization method for Enrichment of Evaluation (PROMETHEE) have been applied. Seven criteria for the evaluation of five alternatives for the transport of containers by heavy-duty vehicles and by rail have been studied. The results have been verified by comparison with other studies. The obtained results show that the criteria are carbon dioxide emissions during transportation (0.30), security and safety (0.31), infrastructure charges (0.16) and infrastructure characteristic (0.13). It was found that the results for the ranking of the alternatives according to the different approaches are close. It was found that the transport of containers with block-trains is the most suitable alternative for the investigated alternative routes. The developed integrated approaches can also be applied to make research in other scientific fields.
Problem of utilization of asbestos-cement sheets in Poland
Authors: Ulewicz Malgorzata , Liszewski Wieslaw
Published: June 2023

The management of construction and demolition waste in individual EU countries is very diverse, especially the management of asbestos waste. In Poland, asbestos-cement products until 1997 were a commonly used roofing material for both residential and farm buildings, especially in rural areas. Due to the harmfulness of this product, a ban on its production and use has been introduced in European countries. Poland, as the only country in the European Union, introduced in 2002 the “Programme for the removal of asbestos from the country for the years 2009-2032”, which defines activities related to the removal and disposal of asbestos products. The paper analyzes the level of generated asbestos construction waste for individual voivodeships, and the degree of its development, together with the identification of obstacles in the effective process of disposal. It has been shown that the asbestos disposal process is very slow and impossible to implement within the assumed time limit. The cover replacement costs are high (net from EUR 54.71 to EUR96.60 per 1 m2 of roof surface; calculated for the first quarter of 2023). The costs of replacing the asbestos-cement roofing with an environmentally safe one, made for a farm building with an area of 180 m2, are very high and range from EUR 11,135.54 to EUR 18,774.47. Currently, in Poland more than 60% of inventoried asbestos waste awaits disposal. The management of dismantled asbestos-cement coverings by depositing them in landfills is not an effective way of using this material, but only shifts the problem of its actual disposal in time.
Influence of polymer on mechanical strength and structure of mortar
Authors: Yu Chaocheng , Zhao Zhiguang , Qu Xiaoling , Zhao Sanyin
Published: June 2023

The paper mainly studies the effects of polymer on the mechanical strength and microstructure of mortar, and analyzes the influence of 1%, 5%, 10% polymer content and curing methods on the strength growth and microstructure. The results show that the addition of polymer prolongs the initial and final setting time. When the polymer content is less than 10%, the compressive strength gradually decreases with the increasing polymer content, and the flexural strength of mortar after polymer addition decreases slightly. The mechanical strengths are the best under 7 days of water curing and 21 days of air curing. SEM analysis shows that high content of polymer will delay and inhibit the hydration of cement, and introduce a certain amount of bubbles, thus affecting the strength.
Estimation of evapotranspiration empirical coefficients of scots pine (Pinus sylvestris) under climate change conditions
Authors: Zyromski Andrzej , Wdowikowski Marcin , Kazmierczak Bartosz
Published: June 2023

The aim of this study was to assess the feasibility of estimating the evapotranspiration of Scots pine (Pinus silvestris) using an indirect method. The field experiment was conducted at the Agro and Hydrometeorology Observatory of the Faculty of Environmental Engineering and Geodesy of the Wrocław University of Life Sciences in Poland from 1 May to 31 October from 2016 to 2019. The experiment covered the period from the 6th to the 9th year of cultivation of Scots pine (Pinus silvestris) on arable land. Evapotranspiration of Scots pine (ETR) was measured in soil evaporometers of 0.3 m2 and 0.7 m soil monolith thickness, with a daily time step, in triplicate. In order to avoid the oasis effect, the soil evaporometers were installed so that the measured trees grew in a compact enclave, as they do under natural conditions. In parallel, the actual evaporation values from the free water surface were measured directly with the EWP 992 evaporometer, and the daily indicator evaporation values were calculated using the FAO Penman-Monteith formula. In the next step, using evaporation measurements from the EWP 992 evaporometer and determined with the FAO Penman-Monteith formula, decadal and monthly empirical coefficients were determined to estimate the evapotranspiration of Scots pine. Evaluation of the weather conditions in the individual years of the experiment was also carried out, relating it to the normative multi-year period 1981–2010.
Influence of infill wall in RC frames
Authors: Aliyu Ahmad Mubarak , Kabiru Adamu
Published: June 2023

The function of infilled masonry reinforced concrete (RC) frame buildings during severe events such as blast caused by explosions or earth movement – earthquake and other significant lateral displacement could seriously damage a supporting frame column, causing the frame to collapse completely or partially. The behaviour of a framed structure associated with loss of supporting column as a result of vertical gravitational loading imbalance has received less attention in recent studies. When a supporting column is removed in a framed structure, it is assumed that the member deflection increases significantly, which could be restrained by the infill wall, resulting in contact forces between the infill wall and the frame. These interaction forces have an impact on the distributions of shear forces and bending moments along the frame components, which can contribute to frame stability or failure. The current study aims to address these key issues and gain insight into the performance of infilled-frame activity in the absence of a peripheral supporting column. This study’s methodology is based on a numerical investigation of a typical RC infilled-frame subjected to gravitational loading using the three-dimensional discrete element code (3DEC) model. The scenarios considered include; investigation of the loaded structure with the column in place, without the column in place but supported by an infilled wall and with the effect of lateral load acting on the structure without a peripheral column support. The results indicate that masonry infill walls considerably increase the frame resistance to vertical load action, compared to the resistance of a bare frame up to 18%, therefore, the infill wall could play a major role in maintaining the structural system stability/integrity and reducing the likelihood of a progressive collapse.
Overcoming mathematical anxiety to promote progress in mathematics during undergraduate engineering studies at university
Authors: Aruvee Eve , Vintere Anna
Published: June 2023

Mathematics (math) is one of the logical and practical academic disciplines, which is one of the basic competencies in engineering. Despite that, some students have difficulty to learn math, which is determined by several cognitive and emotional factors. Math anxiety is one of the emotional factors that causes learning difficulties in math. Many students experience anxiety, fear, tension, or discomfort when faced with math, what affect students’ achievement. Math anxiety can be caused by several factors: lack of appropriate math knowledge, learning strategies, application of math in real life, limited exam time, lack of specific materials as well as personality type, lack of confidence, and stereotypes related to math. It is already proved, that achievement in math increases when anxiety is controlled. Therefore, to promote progress in math during engineering studies at university, the aim is to identify the most important factors that cause mathematics anxiety, as well as existing experiences in overcoming them. To develop the methodology of this study, a study of the scientific literature on math anxiety is performed, considering the above-mentioned math learning difficulties. In the case of math anxiety three factors are analysed: student’s prior mathematical experience as well as learning strategies at pre-university and university education level. The article looks at three approaches to learning math that are commonly used by students in their studies of math at university: (1) The use of ICT tools and math software to understand the concepts of math and solve independent work tasks; (2) The link between teaching of math and real/ everyday life; (3) Cooperative learning during additional math classes. The effectiveness of these approaches is characterised using the data from the quality monitoring of the math study process at the authors’ universities and students’ survey results as well as math teachers focused interviews.
Unpacking urban: towards common definition
Authors: Veckalne Regina , Tambovceva Tatjana
Published: June 2023

The lack of a universally accepted definition of the term “urban” has led to inconsistencies and challenges in the fields of research, policy, and practice. This paper addresses this problem by conducting a systematic literature review and bibliometric analysis of the concept of “urban”. By understanding the significance of a clear definition of “urban”, this study aims to facilitate better communication and comprehension among practitioners, policymakers, and researchers working in the field. The paper begins by tracing the historical origins of the urban concept and the factors contributing to the development of urban areas. It then examines the traditional, functional, social, and cultural approaches used to define urban areas, while also discussing the challenges and limitations of these definitions. The analysis reveals that a place can be identified as “urban” if it has a diverse and complex social structure, a vibrant economy, and a high concentration of facilities and cultural activities. The characteristics of an urban area may include diversified population, densely built environment, and an emphasis on business, leisure, and other forms of cultural expression. Despite grappling with issues such as pollution, crime, and social injustice, urban areas often embody creativity, inventiveness, and a fast-paced lifestyle. A comprehensive definition of the term “urban” may also contribute to the development of a widely accepted definition of “rural”, as the two terms are often considered opposites.
Effect of shell temperature on solidification organization of equiaxed crystal blade
Authors: Cao Guoqiang , Zhang Bo , Li Gang , Peng Wenya
Published: June 2023

The investigation was conducted into the effects of different shell preheating temperatures (1100 °C, 1150 °C, and 1180 °C) on the organization of solidification of isometric crystalline blades made for an aero-engine. The experimental results show that with the increase of shell temperature, the dendrite spacing and dendrite robustness gradually increase, while the area between dendrites gradually increases. The size of the eutectic gradually increases as the shell temperature rises, and there is no obvious regularity in the eutectic content. The size and content of carbide show a trend of decreasing first and then becoming larger, and the size relationship was 1180 °C > 1110 °C > 1150 °C. There is no obvious difference in the composition of carbides at different shell temperatures, all of them are MC-type carbides, and none of them decompose. At 1150 °C, γ΄ phase has a smaller size, the best cubical and most regular arrangement, while the largest size, worst cubicization and most irregular phase at 1180 °C.
Effect of shell temperature in thermal control solidification process on microstructure and stress rupture property of cast equiaxed superalloy
Authors: Cao Guoqiang , Shen Yuqiao , Li Gang , Peng Wenya
Published: June 2023

Cast equiaxed superalloy is commonly used in the manufacture of engine turbine blades and complex structural castings due to its excellent casting properties and comprehensive mechanical properties. The more adaptable thermal control solidification process is usually used to refine the equiaxed crystal structure. In this paper, the microstructure and fracture surface of this alloy after solid solution were observed and characterized by means of OM, SEM, and EDS, and the effects of thermally controlled solidification processes with different shell temperatures on the microstructure and stress fracture properties of this alloy were investigated. The results showed that in this cast equiaxed crystal alloy, increasing the shell temperature from 1300 °C to 1330 °C causes the grain size to grow, microporosity to significantly decrease, and eutectic content and size to slightly increase. Both S1 and S2 alloys formed MC and M6C carbides after solid solution treatment. The size and content of carbides increased as the shell temperature rose, whereas the size and content of the γ’ phase decreased. As the shell temperature increases, the stress rupture properties increase slightly, while the degree of rafting increases dramatically. Cracks are mainly formed at the aggregation of microporosity, eutectics, and carbides. The reasons why cracks occur in the two alloys can differ. This study provides guidance for the design of a thermal control solidification process for cast equiaxed superalloys.
Estimation of impact of participation in public green procurement of food on farm numbers in rural Latvian counties
Authors: Hazners Juris , Zvirbule Andra
Published: June 2023

Green Public Procurement (GPP) of food in Latvia is a tool that directly provides the increase in sales of local food products via purchases by local communities and state institutions in sectors such as education, defence, interior, healthcare and welfare. Public procurement within the framework of GPP ensures that the purchase of the food products or catering services minimizes the environmental impact while having positive social consequences. The share of local farms in the total directly provided product volumes within GPP is minor and the bulk of the farm produce goes through wholesale, food processing and public catering companies. The Latvian agriculture is experiencing continuous structural changes with the consolidation and decrease in farm numbers. The rate of the farm “disappearance” in rural counties with companies participating in the food GPP is similar to the counties without such companies. This could lead to the expectations that changes in the farm numbers are not affected by participation in GPP. While the previous research on the impact of GPP in the European countries has extensively focused on the environmental, economic and social issues, the causal inference with respect to changes in farm numbers has not been addressed. Coarsened exact matching (CEM) is the method for the estimation of the causal effects that has been widely applied to observational data. The advantages of CEM are associated with the reduction of the differences between multivariate distributions of covariates in treatment and control groups by pruning the data with splitting into pre-determined bins. The research objective is to evaluate the net impact of the participation in GPP by a rural county on the number of farms in this county. Considering the participation in GPP as a treatment variable in the rural county panel data, the results of CEM reveal positive net impact on the farm numbers in the treated counties. Albeit the direct farm participation in food GPP is negligible, the participation of other companies in food GPP has positive net direct impact on farm numbers. Participation in a food GPP over the period from 2018 to 2020 has contributed to sustainability of 2179 farms. Considering that only about 21% of rural communities have direct participation in food GPP, a modification of the National regulation of GPP towards an increased preferences for local suppliers would improve the resilience of the farming sector.
Use of ozone in oats drying
Authors: Aboltins Aivars , Palabinskis Janis , Jansons Roberts Vilis
Published: June 2023

The present article describes the drying of wet oats at different temperatures with ozonated and non-ozonated air. Experimental results show that moisture removal during drying of oats at temperature T = 21 °C is higher using ozonated air than non-ozonated air. Moreover, after a 4-hour drying process, it amounts to 1.6 g per kg of oats. Using heated air, the difference in moisture removal decreases. At the beginning of the drying process, a decrease in the temperature of the drying agent can be observed in the layer, which is caused by the removal of moisture from the surface of grains. By increasing the air temperature from 21 °C to 40 °C, in the first hour of drying, 12.6 more g·kg-1 is removed than with unheated air, and in the second hour even more than 15 g·kg-1. By increasing the drying temperature from 40-60 °C, this difference is much smaller -in the first hour only 3.5 g·kg-1, in the second already more than 7.3 g·kg-1. This could be explained by the fact that as the temperature increases, the thickness of the layer in which the drying process takes place increases. By processing the obtained experimental data, a relationship was obtained that connects the drying rate and temperature with the amount of moisture removed.
Optimization of a glucagon-like peptide 1 receptor antagonist antibody for treatment of hyperinsulinism
Authors: M. Peterson Sean , A. Juliana Christine , F. Hu Cameron , Chai Jinghua , Holliday Carson , Y. Chan Kara , G. Lujan Hernandez Ana , Challocombe Zoe , Wang Linya , Han Zhen , Haas Nikhil , Stafford Ryan , Axelrod Fumiko , Z. Yuan Tom , D. De León Diva , K. Sato Aaron
Published: June 2023

Congenital hyperinsulinism (HI) is a genetic disorder in which pancreatic beta cell insulin secretion is excessive and results in hypoglycemia that can cause brain damage or death without treatment. Most patients with loss-of-function mutations in ABCC8 and KCNJ11, the genes encoding the beta cell ATP sensitive potassium channel (KATP), are unresponsive to diazoxide, the only FDA approved medical therapy, and require a pancreatectomy. The glucagon-like peptide 1 receptor (GLP-1R) antagonist exendin-(9-39) is an effective therapeutic agent to inhibit insulin secretion in both congenital and acquired hyperinsulinism. Previously, we identified a highly potent antagonist antibody, TB-001-003, which was derived from our synthetic antibody libraries that were designed to target G protein-coupled receptors. Here, we designed a combinatorial variant antibody library to optimize the activity of TB-001-003 against GLP-1R and performed phage-display on cells overexpressing GLP-1R. One antagonist, TB-222-023, is more potent than exendin-(9-39), also known as Avexitide. TB-222-023 effectively decreased insulin secretion in primary isolated pancreatic islets from a mouse model of hyperinsulinism, Sur1-/- mice, and in islets from an infant with HI as well as increased plasma glucose and decreased the insulin to glucose ratio in Sur1-/- mice. These findings demonstrate that targeting GLP-1R with an antibody antagonist is an effective and innovative strategy for treatment of hyperinsulinism.
Deletion of carboxypeptidase E in beta cells disrupts proinsulin processing but does not lead to spontaneous development of diabetes in mice
Authors: Chen Yi-Chun , J. Taylor Austin , M. Fulcher James , C. Swensen Adam , Dai Xiao-Qing , Komba Mitsuhiro , L.C. Wrightson Kenzie , Fok Kenny , E. Patterson Annette , I. Klein-Geltink Ramon , E. MacDonald Patrick , Qian Wei-Jun , Bruce Verchere C.
Published: June 2023

Carboxypeptidase E (CPE) facilitates the conversion of prohormones into mature hormones and is highly expressed in multiple neuroendocrine tissues. Carriers of CPE mutations have elevated plasma proinsulin and develop severe obesity and hyperglycemia. We aimed to determine whether loss of Cpe in pancreatic beta cells disrupts proinsulin processing and accelerates development of diabetes and obesity in mice. Pancreatic beta cell-specific Cpe knockout mice (βCpeKO; Cpefl/fl x Ins1Cre/+) lack mature insulin granules and have elevated proinsulin in plasma; however, glucose-and KCl-stimulated insulin secretion in βCpeKO islets remained intact. High fat diet-fed βCpeKO mice showed comparable weight gain and glucose tolerance compared to Wt littermates. Notably, beta-cell area was increased in chow-fed βCpeKO mice and beta-cell replication was elevated in βCpeKO islets. Transcriptomic analysis of βCpeKO beta cells revealed elevated glycolysis and Hif1α-target gene expression. Upon high glucose challenge, beta cells from βCpeKO mice showed reduced mitochondrial membrane potential, increased reactive oxygen species, reduced MafA, and elevated Aldh1a3 transcript levels. Following multiple low-dose streptozotocin treatment, βCpeKO mice had accelerated hyperglycemia with reduced beta-cell insulin and Glut2 expression. These findings suggest that Cpe and proper proinsulin processing are critical in maintaining beta cell function during the development of hyperglycemia.
Immunological Disorders in Adult Patients with Trichophytia and Microsporia of the Genital Area, Tajikistan
Authors: SH Munieva
Published: June 2023

To study the state of the main parameters of immunity in the peripheral blood of adult patients with trichophytia and microsporia of the skin of the genitals and surrounding areas. Materials and Methods: 137 patients (88 men, 49 women) aged 16 to 40 years were examined. The duration of the disease was, on average, 6.9 ± 0.2 weeks. 77.4% of patients with mycoses became sexually infected. 28.5% of patients had sexual promiscuity. Research Methods: microscopic, cultural, and immunological. Results: A statistically significant decrease in the number of CD4 lymphocytes (P < 0.02), PANL (P < 0.01), FN (P < 0.01), IL-10 (P < 0.01) and an increase in the content of IgA (P < 0.01), IgM (P < 0.01), CIC (P < 0.01), IL-1β (P < 0.01) and IL-6 (P < 0.01) were detected in the blood of the patients. Patients with a disease duration of up to 1 month showed a change in 8 of the 16 immunological indicators studied, but not a single indicator of cellular immunity, in patients with a disease duration of more than 1 month - 11, including 2 main indicators of cellular immunity (CD3 and CD4 lymphocytes) Conclusion: In adult patients with zoonotic trichophytia and microsporia with atypical localization, there is an inhibition of cellular immunity, phagocytic reactions, anti-inflammatory cytokines and an increase in the activity of humoral and proinflammatory cytokines. Immunological disorders are more pronounced in patients with the disease duration of more than 1 month.
Searching for Etiopathophysiological Links for ‘Long Covid’
Authors: V Nikhra
Published: June 2023

Introduction: The Long Covid Syndrome: The post-acute sequelae of COVID-19 (PASC) or ‘Long Covid’ is a varying, relapsing, and remitting disorder that may follow recovery from acute infection with SARS-CoV-2 in some patients and last for a variable period. It has a protracted course culminating as lingering and incapacitating illness predisposed by certain constitutional factors and comorbidities. Akin to COVID-19, it primarily affects the respiratory system, but other systems such as neurologic, cardiologic, hepatic, renal and pancreatic, and cutaneous systems may be involved. As the infection can harm the immune system, various organs including lungs fall prey to the aberrant immune response. Etilogical Correlates and Pathogenesis: Long Covid is a multisystem disorder entailing multiple symptoms related to various organs. There are several theories about the etiology of Long Covid such as continuing presence of the virus and its biologically active fragments, reinfection with the same or a different variant, dysfunctional immune reactions leading to a chronic inflammatory state, an ill-defined condition exhibiting symptoms of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) suggestive of a complex, multisystem disorder, post-traumatic stress following severe COVID-19 illness and critical care issues, and aftermath resulting due to disturbed microbiota in gut, lungs, and other organs. Long Covid Pathogenesis: New Insights: The SARS-CoV-2 infection activates the humoral immunity leading to formation of antigen-antibody complexes and the antigen-antibody reactions, which may propagate to organ damage. Simultaneously, viral superantigens may overstimulate immune responses, inducing negative feedback loops to hamper immune function and allow the virus to persist and replicate. The persistent virus may contribute to long Covid. There may develop various autoantibodies causing tissue injury and fibrosis in lungs and other organs. The Altered Microbiome leading to the microbial dysbiosis has also been implicated in persisting inflammatory processes culminating as Long Covid. Conclusion: Therapeutic Considerations: With expanding awareness, it has been recommended that all patients after recovery from COVID-19 should have access to healthcare. On the practical side, there are being established clinics for people with Long Covid backed by multidisciplinary teams for supportive and specific treatment and follow up. The anti-fibrotic and anticoagulant agents may be helpful in preventing further lung damage and thrombotic episodes. The role of a COVID-19 vaccine in preventing Long Covid is not known, but it may be helpful in reducing morbidity. The strategies to improve the intestinal dysbiotic microbiota through probiotics and microbial transplant appear promising.
Super Bugs: The Menace of Antimicrobial Resistance
Authors: KO IYEVHOBU
Published: June 2023

Superbugs are bacterial strains that are resistant to various antibiotics. The following types of bacteria have been described as threats of antibiotic resistance to patients in the medical environment or called "super bacteria" in the media: Carbapenem-resistant Enterobacteriaceae (CRE), methicillin-resistant gold Staphylococcus aureus (MRSA), ESBL-producing enterobacteriaceae (extended-spectrum β-lactamase), carbapenem-resistant vancomycin-resistant enterococcus (VRE), multi-drug resistant Pseudomonas aeruginosa, multi-drug resistant Actinobacteria and E. coli H30Rx: Resistance to so-called antibiotics has led to the development of so-called antibiotics. "Super bacteria" that no longer respond to current treatments. The types of antibiotics that can be used to treat these infections are declining, and very few antibiotics are in use. Superbugs are resistant microorganisms, which mean they symbolize one of the most dangerous threats in medical history. The current list of "Superbugs" is not defined. New bacterial strains exhibiting drug resistance are rapidly being identified. Developing new antibiotics against the growing threat of multidrug resistance is still a "dangerous secret" goal. Low returns on investment in antibiotics and unpredictable and often unfeasible authorization pathways by regulators have led many companies to exit the antibiotics market. Hospital pathogens have left the hospital and are following the ranks of community pathogens. As more and more superbugs appear, there is a need to fund and support the development of new antibacterial drugs.
Assessing Natural Anti-Covid Immunity: Serology, Cellular Immunity
Authors: H Banoun
Published: June 2023

It is important to evaluate natural immunity against Covid-19: it is stronger, longer lasting and of better quality than vaccine immunity only humoral (antibody) or cellular adaptive immunity can be assessed; innate immunity is not measurable. Serology is the only routine test, it is the measurement of the antibody level. The measurement of the antibody level leads to an underestimation of the seroprevalence which is already high and above 50% of the population in most countries. The reasons for this underestimation are: The tests are designed against the strain isolated in 2019 in China and the calibration is against convalescent blood collected before June 2020. There is considerable heterogeneity in the commercial tests available. A large percentage of the infected population may have negative serology within months of infection Cellular immunity testing could eliminate these false negatives but it is not routinely applicable and is expensive.
Joint Modelling of the Relationship between CD4 Cell Count and Survival Analysis of HIV Infected Patients Receiving Antiretroviral Therapy, Gweru, Zimbabwe
Authors: F Chipepa
Published: June 2023

Introduction: The main objective of this research is to apply joint modelling technique to assess the relationship between cd4 cell count and survival of ART patients in Gweru, Zimbabwe. The Cox proportional hazards model is mainly used in modelling survival data when the true values of the time-varying covariates are observed. However, most of these measurements are observed with error and to circumvent this problem, measurements are taken longitudinally to reduce the bias caused using such observed measurements in the Cox proportional hazards models. Methods: We conducted secondary data analysis on the Gweru district ART cohort data for the period 2006 to 2010. The association between CD4 cell count and survival time of the patient was determined using a joint longitudinal-survival model. The factors that affected cd4 cell changes were determined using mixed linear regression model and factors associated with survival of ART patients was determined using a Cox proportional hazard model. Shared parameters were used to determine the association between cd4 cell count and survival of the ART patient. Results: A statistically significant direct effect of gender on survival was observed -0.003 (95% CI: -001, -0.002). Also, a highly negative significant association was observed -9.48 (95% CI: -11.7, -7.23), indicating that female patients with high levels of lncd4 had reduced hazard of death compared to male patients. Place of residents of the ART patient had a significant direct effect on survival -0.66 (95% CI: -0.01, 0.003). There is also a highly negative significant association -10.0 (95% CI: -12.4, -7.67), indicating that patients in urban areas and with high lncd4 cell counts had a reduced hazard of death compared to patients in rural areas. Age had a direct effect on survival as the hazard of death increases as we move from one age group to another. A highly negative significant association was observed -9.4 (95% CI: -11.6, -7.17) indicating that the hazard of death for patients with high lncd4 decreases as we move down the age groups.
Effect on MicroRNA-92a in Atherosclerosis along with FlowMediated Vasodilation Study
Authors: Kazumi Kazumi
Published: June 2023

Atherosclerosis has been regarded as an inflammatory disease. The vascular endothelium is considered as having multiple functions, regulating vascular tone, thrombosis, haematosis, permeability and cell adhesion. The emergence of microRNAs (miRNAs) as significant regulators of pathophysiological processes has indicated novel molecular insights and provided new therapeutic targets in atherosclerotic condition. Many studies have revealed that miRNA are associated with cardiovascular disease (CVD). With respect to miR-92a, miR -92a, a member of the miR-17 to miR-92 cluster, is expressed highly in endothelial cells (ECs) and regulated by shear stress. Both In vitro and vivo, miR-92a expression is highly induced in atheroprone regions compared with atheroresistant regions under disturbed flow (d-flow) condition. The clinical and experimental studies have suggested that inhibition of miR-92a can contribute to the improvement of endothelial dysfunction, inflammation, and oxidative stress in atherosclerosis. Recent reports showed that antimiR-92a as novel therapeutic options can be attributed to the endothelial cell autophagy and cardiomyocyte metabolism and that mechanistically, atherosclerotic status promote the packaging of functional miR-92a-3p into endothelial microvesicles, thereby promoting angiogenic response into recipient endothelial cells. It is strongly suggested that miR-92a-3p, having novel biological function and mechanism is a potent therapeutic target in atherosclerosis-related diseases. It is putative that flow-mediated vasodilation (FMD) study, early surrogate marker of endothelial function may in part reflect miR-92a, multifunctional biomarker
Clinicopathological Association of DNA Repair Gene Polymorphisms in Colorectal Cancer Patients
Authors: RG Nandita
Published: June 2023

Several polymorphisms in DNA repair genes, especially ERCC1 C118T, ERCC2 Lys751Gln and XRCC1 Arg399Gln have been found to affect treatment efficacy and prognosis in patients with colorectal cancer (CRC). However, scarce reports available on the association of these polymorphisms with clinicopathological parameters. As clinicopathological factors provide important information to determine prognosis in CRC, present study evaluated association of DNA repair gene polymorphisms with clinicopathological parameters. ERCC1 C118T, ERCC2 Lys751Gln and XRCC1 Arg399Gln polymorphisms were studied by PCRRFLP in 143 primary CRC patients. For ERCC1 C118T polymorphism, predominance of heterozygous C/T (56%) was noted compared to wild type C/C (29%) and variant T/T (15%) genotypes. ERCC2 Lys751Gln polymorphism showed 44% of wild type A/A, 40% of heterozygous A/C, and 16% of variant C/C genotypes. XRCC1 Arg399Gln polymorphism displayed wild type G/G (48%), heterozygous G/A (42%), and variant A/A (10%). In relation to clinicopathological parameters, ERCC1 C118T polymorphism was significantly associated with tumor site (P=0.021); tumor location (P=0.039); and tumor differentiation (P=0.041). Moreover, a significant correlation of ERCC2 Lys751Gln polymorphism was noted with lymphocytic stromal response (P=0.026) and necrosis (P=0.041). However, XRCC1 Arg399Gln polymorphism was not significantly associated with clinicopathological factors. Further, a significant positive correlation was observed between ERCC2 and XRCC1 polymorphism (P=0.002). To conclude, higher frequency of ERCC1 118 variant C/T and T/T genotypes was noted in patients with colon cancer and right side located tumors. Variant C allele of ERCC2 751 polymorphism was associated with less aggressive colorectal tumors. Moreover, significant association between ERCC2 and XRCC1 polymorphisms proposes interlink of genes of different DNA repair pathways in CRC.
Integrated Approach for Diagnosis, Management and Prevention of Gall Bladder Carcinoma
Authors: P Katru
Published: June 2023

Ayurveda, “The Science of Living”, it has been in existence since the beginning of time and has been giving the health solutions for various named and unnamed diseases, to the humankind since ages. Cancer is indirectly described in Ayurveda texts in the form of various terms like ‘arbud’, ‘gulma’, ‘granthi’ which have been coined that could be related to cancer. Though an uncommon malignancy Gallbladder cancer is the commonest and fatal biliary malignancy as it is not easily diagnosed in early stages. The integrated approach for early diagnosis and prevention through Ayurveda could be helpful in the management of the biliary malignancy. Aims and Objectives • To review, evaluate, elaborate and discuss the gallbladder cancer as per Ayurveda and modern medicine. • To evaluate, elaborate and discuss the current and ancient approach to the diagnosis, management and prevention of gallbladder cancer. Materials and Methods: This Research Scientific Paper is based on Ayurvedic Clinical Experiences in Cancer & Gall Bladder Cancer, Research Article published on Cancer in Medical Journal. Ayurvedic and Modern Text have been reviewed to collect, analyze, evaluate, elaborate and discuss of concern subjects. A Medline, PubMed database search was performed to identify articles published using the keywords ‘carcinoma of gallbladder’, ‘gallbladder cancer’, ‘gallbladder neoplasm’, ‘cholecystectomy’, ‘arbud’, ‘gulma’. Conclusion: Gall Bladder Cancer can be diagnosed and managed by using diagnostic method recommended in Modern Medicine as well as by using basic principles and medicines described in Ayurveda. Gall Bladder Cancer can be prevented by reducing the risks factor of this disease through follow the wholesome diet and normal lifestyle described in Ayurveda.
An Incidental Finding of Duodenal Carcinoid Tumor
Authors: M Paravathaneni
Published: June 2023

Neuroendocrine tumors (NETs) are rare, well-differentiated tumors that arise from enterochromaffin cells and are typically found within the digestive tract. Many NETs found within the gastrointestinal tract (GI) are located in the ileum, with duodenal NETs relatively rare. We describe a 56-year-old morbidly obese female who underwent upper gastrointestinal endoscopy (EGD) for refractory gastroesophageal reflux disease (GERD) and was incidentally diagnosed with a grade I NET within the duodenal bulb, which was subsequently resected. As these tumors are often indolent, it is important for clinicians to be cognizant of acting on these incidental findings to help prevent the systemic effects of carcinoid syndrome.
Rectal Neuroendocrine Tumor: Clinical Case Report
Authors: LA Buexm
Published: June 2023

The rectal neuroendocrine tumor (RNT) is a rare neoplasm that initiates in the neuroendocrine cells of the digestive tract called Kulchitsky cells, which originate from Lieberkün crypts. About 50% of patients are asymptomatic and their diagnosis is made incidentally by routine colonoscopies. This clinical report presents a neoplasm considered rare in a young patient and emphasizes the importance of its early diagnosis. A 23-year-old man, without comorbidities, was referred to the referral service to investigation a single occurrence of postprandial abdominal pain in the left flank. Polypoid fragment of the rectal mucosa was extracted during a colonoscopy, making it possible to perform a complete removal with free margins of the rectal NET. After histopathological and immunohistochemical evaluation, the diagnosis of RNT grade 1 was made. Although RNT is rare and asymptomatic, early screening is necessary to facilitate diagnosis in the early stage of the disease, leading to a greater possibility of treatment and a better prognosis of the disease.
Sentinel Lymph Node in Breast Cancer, Our First Experience at Nicaragua. Case Report
Authors: F Medrano
Published: June 2023

Morton introduced cutaneous lymphoscintigraphy in melanoma. His results permitted to reproduce sentinel lymph nodes(SLN) in other areas. Krag and Weaver implemented portable gamma radiation detectors in breast cancer. The aim of this article is to describe the first expertise in our hospital using nuclear medicine in breast cancer and the methodological aspects of SLN and reviewing the international literature. Case Report: Female 54 years, no family history of breast cancer. Medical exam detected a mass of 3x2 cm in the upper outer quadrant of the left breast, there is no axillary mass. The Ultrasound: BIRADS IV A. Mammography: BI-RADS V Preoperative Classification: T2N0M0 Tru Cut Biopsy: Invasive carcinoma no type determined. Triple negative. Extension studies were negative. The lymphoscintigraphy done according to international protocol. Methylene blue was used in conjunction with the radiotracer; a periareolar sub dermal injection was given in the operating room. The Surgery performed on the day marked. After localized the scintigraphic hot spots in vivo with the gamma probe Nuclear Lab DGC II. The intraoperative frozen section analysis used with Haematoxylin and Eosin staining. Two SLN reported as metastases Negative. The axillary dissection was deferred. There were no complications. Post-surgical pathologic report showed invasive carcinoma no type determined size 35 x 30 x 28 mm, unifocal. In situ ductal carcinoma and in situ lobular carcinoma unidentified and lympho-vascular unidentified invasion. There is no tumoral extension to the skin. All margins were reported negative.pT2pN0. Conclusion: Each time that a new therapeutic tool is within reach of the oncologic patients, principally when his effectiveness have been demonstrated to long time. It to make true in low income country increase the challenge for her implementation. However, the multidisciplinary effort of the human resources and the help of the technology development of our institutions permeated to jump the hard barrier that this entails, achieving a great achievement to the patients with breast cancer in our country. This first effort is not distant from the reported in the international literature.
Passive Isolator Design and Vibration Damping of EO/IR Gimbal Used in UAVs
Authors: Görmüş Mehmet Taha , Adın Bilal Faruk , Yayla Paşa
Published: June 2023

One of the most critical factors affecting the quality of the images captured by the surveillance systems used in the unmanned aerial vehicles is the vibrations transmitted from the aircraft to the gimbal. The gimbal used in unmanned aerial vehicles is essential equipment, holding the camera steadily and accurately and pointing it in the desired direction. Within the scope of this article, a passive vibration isolation system design has been made for the two-axis electro-optical gimbal used in the mini unmanned aerial vehicle. By choosing the spring-damper system among different methods, the design that isolates the harmonic vibration from the platform on a single axis has been made using the analytical method. The analytical method was used to create a design that isolates the harmonic vibration from the platform along a single axis. In addition, the part named 'Pan Yoke', which contains this damper system, was designed with a computer-aided design program, and natural frequency values were checked with Ansys modal analysis. The frequency of the vibration transmitted from the air vehicle to the gimbal and the natural frequency of the designed part have been determined to be close to each other, at around 200 Hz. The natural frequency values of this part were optimised with various design changes and topology optimisations to prevent the part from resonating.