bluuebunny/crossref_metadata_2025 huggingface dataset:
Copper Extraction from Low-Grade Chalcopyrite in a Bioleaching Column Assisted by Bioelectrochemical System
Authors: Zhang Xueming , Zhang Shaohui , Huang Tao , Jin Zhixin
Published: November 2021

Low-grade ores, tailings and solid wastes contain small amounts of valuable heavy metals. Improper disposal of these results in the waste of resources and contamination of soil or groundwater. Accordingly, the treatment and recycling of low-grade ores, tailings and solid wastes attracted much attention recently. Bioelectrochemical system, an innovative technology for the removal and recovery of heavy metals, has been further developed and applied in recent years. In current study, the low-grade chalcopyrite was bioleached with the assistance of microbial fuel cells. Copper extraction along with electricity generation from the low-grade chalcopyrite were achieved in the column bioleaching process assisted by MFCs. Results showed that after 197 days bioleaching of low-grade chalcopyrite, 423.9 mg copper was extracted from 200 g low-grade chalcopyrite and the average coulomb production reached 1.75 C/d. The introduction of MFCs into bioleaching processes promoted the copper extraction efficiency by 2.7 times (3.62% vs. 1.33%), mainly via promoting ferrous oxidation, reducing ORP and stimulating bacterial growth. This work provides a feasible method for the treatment and recycling of low-grade ores, tailings and solid wastes. But balancing energy consumption of aeration and circulation frequency and chemicals consumption of acid to improve the copper extraction efficiency need further investigation.
A Novel Prognostic Nomogram for the 2-year Survival in Human Epidermal Growth Factor Receptor 2 Positive Breast Cancer Patients
Authors: Chen Mengdi , Wu Jiayi , Liu Deyue , Chen Weilin , Chen Weiguo , Shen Kunwei , Zhu Li
Published: November 2021

Background: Targeted therapies have largely improved prognosis of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. Yet, disease can still progress rapidly for some patients in the first two years after diagnosis. Our study aimed to establish a nomogram model to predict the 2-year breast cancer-specific survival (BCSS) in early HER2-positive breast cancer patients. Methods: A total of 32,481 HER2-positive patients derived from Surveillance, Epidemiology, and End Results (SEER) database were included in the construction of nomogram. Concordance index (C-index) and calibration curve were used to evaluate the discrimination ability and predictive accuracy. We tested the model in 804 patients from Shanghai Jiao Tong University Breast Cancer Data Base (SJTU-BCDB). Results: Age, estrogen receptor (ER) status, progesterone receptor (PR) status, histologic type, T stage and N stage were selected to construct the nomogram according to multivariable analysis. The 2-year BCSS rate was 95% and 60% for patients at low risk (<8 points) and high risk (>13 points) respectively. The C-index of model derived from SEER database is 0.81 (95%CI 0.79-0.83). Sensitivity analysis was performed in patients after breast surgeries with the C-index of 0.81 (95%CI, 0.79-0.83). Validation in 804 patients from SJTU-BCDB showed respective C-index of 0.77 (95%CI, 0.62-0.92) in total population, 0.67 (95%CI 0.44-0.90) and 0.90 (95%CI 0.81-0.90) in patients who received anti-HER2 therapy or not. Discussion: The novel nomogram can predict the 2-year survival outcome in HER2-positive patients independent of receiving anti-HER2 therapy or not and allow clinicians to adjust therapeutic strategies for patients with higher risk.
Screening the Hub Genes and Analyzing the Mechanisms in Discharged COVID-19 Patients Retesting Positive through Bioinformatics Analysis
Authors: Fang Ke-Ying , Liang Gui-Ning , Zhuang Zhuo-Qing , Fang Yong-Xin , Dong Yu-Qian , Liang Chuang-Jia , Chen Xin-Yan , Guo Xuguang
Published: November 2021

Background: With the worldwide spread of COVID-19, people’s health and social order have been exposed to enormous risks. After encountering patients who test positive again after discharge, our study analyzed the pathogenesis to further assess the risk and possibility of virus reactivation.Methods: A separate microarray was acquired from the Integrated Gene Expression System (GEO), and its samples were divided into two groups: a “convalescent-RTP” group consisting of recovery and “retesting-positive” (RTP) patients (group CR) and a “health-RTP” group consisting of healthy control and RTP patients (group HR). The enrichment analysis was performed with R software, obtaining the gene ontology (GO) and Kyoto pluripotent stem cells (KEGG) of the genes and genomes. Subsequently, the protein–protein interaction (PPI) networks of each group were established and the hub genes were discovered using the cytoHubba plug-in.Results: In this study, 20 differentially expressed genes were identified, and 6622 genes were identified in the group CR, consisting of 5003 up-regulated and 1619 down-regulated genes. Meanwhile, 7335 genes were screened in the group HR, including 4323 up-regulated and 3012 down-regulated ones. The GO and KEGG analysis of the two groups revealed significant enrichment of these differentially expressed genes in pathways associated with immune response and apoptosis. In the PPI network constructed, 10 hub genes in group CR were identified, including TP53BP1, SNRPD1, SNRPD2, SF3B1, SNRNP200, MRPS16, MRPS9, CALM1, PPP2R1A, YWHAZ. Similarly, TP53BP1, RPS15, EFTUD2, MRPL16, MRPL17, MRPS14, RPL35A, MRPL32, MRPS6, POLR2G were selected as hub genes.Conclusions: Using the messenger ribonucleic acid (mRNA) expression data from GSE166253, we explore the pathogenesis of retesting positive in COVID-19 from the immune mechanism and molecular level. We found TP53BP1, SNRPD1 and SNRPD2 as hub genes in RTP patients. Hence, their regulatory pathway is vital to the management and prognostic prediction of RTP patients, rendering the further study of these hub genes necessary.
A Closed-loop Control for Swing System and Energy Regeneration Analyses of the Multi-system of Grasp Steel Machine
Authors: Yan Yunqi , Wang Puquan , Xu Yun , Shi Yan , Liao Yinghua
Published: November 2021

Facing the environment problems, the improvement on the efﬁciency of the construction machinery is highly demanded, meanwhile, large energy wasted in hydraulic slewing systems, reaching the desired speed slowly and vibration in braking are widespread. In this paper, a closed-loop control swing system (CCSS) is proposed. In this system, bidirectional variable pump controls the change of oil flow by programmed software algorithm, instead of pilot actuated reversing valve, which signiﬁcantly improves the efficiency of hydraulic circuit. Based on the model structures, we develop a hydraulic swing prototype and verify the advantages of our design means of theoretical calculation and simulation. It verifies that CCSS and based on accumulator slewing system(BASS) can respectively save 875.5 KJ and 347.2 KJ more than OCSS with operational weight of 100 tons grasp steel machine, which can support theoretical basis for energy conservation and environmental protection to study the new type of engineering machinery.
Semen Parameters Are Seriously Affected in Acephalic Spermatozoa Syndrome
Authors: Ying Li-juan , Liu Qing-ting , Yu Lin , Yang Tingting , Wu Ying-bi , Xu Jing-yan , Jia Ye-lin , Zheng Yan , Deng Dong , Li Fu-ping
Published: November 2021

Objective: To evaluate the effect of acephalic spermatozoa syndrome on sperm quality in semen with different proportions of headless sperm.Design: Case control study.Setting: Andrology Laboratory.Patient(s): A total of 391 patients with headless sperm and 400 prenatal examination patients with no headless sperm who underwent semen analysis at the andrology laboratory.Intervention(s): None.Main Outcome Measure(s): The correlation of the proportion of headless sperm in semen with semen parameters.Result(s): All semen parameters except the semen volume were negatively (P<0.05) correlated with the proportion of headless sperm in the semen. The semen samples were divided into three groups based on the proportion of headless sperm (PHS) as follows: 0<PHS≤10% (n=249, group A), 1020% (n=71, group C). Nearly all semen parameters were significantly lower in group B and group C than in the control group (P<0.05). However, in group A, only the vitality and motility parameters were lower than those of the control group.Conclusion(s): Semen samples containing headless sperm tend to have lower semen parameters than samples without headless sperm. Increases in the proportion of headless sperm in semen samples are associated with decreases in semen quality.
Recruitment of Regulatory T Cells with rCCL17 Promotes M2 Microglia/Macrophage Polarization Through TGFβ/TGFβR/Smad2/3 Pathway in a Mouse Model of Intracerebral Hemorrhage
Authors: Deng Shuixiang , Jin Peng , Liu Shengpeng , Huang Lei , Sherchan Prativa , Cui Yuhui , Zhang John H. , Gong Ye , Tang Jiping
Published: November 2021

Background
Intracerebral hemorrhage (ICH) is a devastating neurological disease with high mortality and morbidity. The microglia activation and peripheral inflammatory cells infiltration play an important role in the ICH prognosis. Previous studies have demonstrated that regulatory T cells (Tregs) ameliorated neuroinflammation following experimental ICH. However, the specific molecular mechanism underlying such effects of Tregs remains unclear. In the present study, our aims were to examine the effect of Tregs recruitment induced by recombinant CC chemokine ligand 17(rCCL17) in an intrastriatal autologous blood mouse model of ICH and to determine whether the TGF-β/TGF-βR/Smad2/3 pathway was involved in Tregs promoted M2 microglia/macrophage polarization.
Methods
A total of 404 adult CD1 mice (male, eight-week-old) were subject to sham surgery or autologous blood injection of ICH. A CD25-specific mouse antibody or isotype control mAb was injected intraperitoneally 48h prior to ICH induction to deplete Tregs. Recombinant CCL17 (rCCL17), a C-C chemokine receptor 4 (CCR4), was delivered intranasally at 1 h post-ICH. SB431542, a specific inhibitor of TGF-β was administered intraperitoneally 1 h before ICH induction. Post-ICH assessments included neuro-behavior evaluation, brain edema, hematoma volume, hemoglobin content, western blotting, double immunofluorescence staining and immunohistochemistry.
Results
Endogenous brain expressions of CCL17 and Tregs marker Foxp3 as well as the number of Tregs in the perihematomal region were increased following ICH. The Tregs deletion by a CD25 antibody aggravated short-term neurological deficits and brain edema, increased the level of inflammatory cytokines and peripheral inflammatory cells infiltration, exacerbated hematoma expansion and increased M1phenotypes of microglia/macrophage in ICH mice. The rCCL17 treatment increased the number of Tregs in the brain, reduced hematoma expansion and brain edema, promoted microglia/macrophage polarization toward M2 phenotypes. Moreover, the expressions of brain TGF-β/phosphorylated-Smad2/3 were increased. The neuroprotective effects of rCCL17 were abolished by co-administration of the selective TGF-β inhibitor SB431542.
Conclusions
Our study demonstrated rCCL17 recruited of Tregs to brain in the autologous blood injection model of ICH. Tregs promoted microglia/macrophages polarization toward M2 phenotype and alleviation early brain injury, at least in part, through the TGFβ/TGFβR/Smad2/3 signaling pathway in ICH mice. Thus, rCCL17-mediated Tregs recruitment may provide a promising therapeutic strategy to reduce early brain injury after ICH.
"Net cage" technique in the treatment of inferior pole patella fracture: a novel patella internal fixation technique
Authors: Li Ming , Qi Hongfei , Ma Teng , Li Zhong , Ren Cheng , Lu Yao , Xue Hanzhong , Yang Yanling , Zhang Kun
Published: November 2021

Objective

Fractures of the inferior pole of the patella can cause the knee joint extensor mechanism disorder. The fracture fragments are usually small and comminuted. Therefore, there are certain difficulties in fixation. The purpose of this study is to observe the effect of the "Net cage" technique in the treatment of the inferior pole of the patella.
Methods

This is a retrospective study that included 16 cases of inferior patella fractures (AO/OTA 34-A1) who underwent the "Net cage" technique from March 2017 to June 2020. Collecting their medical records and follow-up results, measuring indicators include the surgical complications of the fixation method, knee joint function, the number of fluoroscopies, fracture healing, and the incidence of soft tissue stimulation.
Results

The fractures of all patients healed smoothly, and there were no complications such as failure of internal fixation and fracture of implants. The average number of intraoperative fluoroscopy was 5.56 times (range: 4-10 times); the average fracture healing time was 10.5 weeks (range: 8-14 weeks) ). No patients reported internal fixation-related soft tissue irritation. At the last follow-up, the knee function showed that the average ROM was 133.75° (range: 120°~140°); The average Bostman score was 27.94 points (range: 24-30 points).
Conclusion

"Net cage" technology for the treatment of inferior pole fractures of the patella has the advantages of reduced fluoroscopy, fixation and stability, early functional exercise, and better knee joints after surgery.
The influence of risk perceptions on close contact frequency during the SARS-CoV-2 pandemic
Authors: Wambua James , Hermans Lisa , Coletti Pietro , Verelst Frederik , Willem Lander , Jarvis Christopher , Gimma Amy , Wong Kerry , Lajot Adrien , Demarest Stefaan , Edmunds W. John , Faes Christel , Beutels Philippe , Hens Niel
Published: November 2021

Human behaviour is known to be crucial in the propagation of infectious diseases through respiratory or close-contact routes like the current SARS-CoV-2 virus. Intervention measures implemented to curb the spread of the virus mainly aim at limiting the number of close contacts, until vaccine roll-out is complete. Our main objective was to assess the relationships between SARS-CoV-2 perceptions and social contact behaviour in Belgium. Understanding these relationships is crucial to maximize interventions' effectiveness, e.g. by tailoring public health communication campaigns. In this study, we surveyed a representative sample of adults in Belgium in two longitudinal surveys (8 waves of survey 1 in April 2020 to August 2020, and 11 waves of survey 2 in November 2020 to April 2021). Generalized linear mixed effects models were used to analyse the two surveys. Participants with low and neutral perceptions on perceived severity made a significantly higher number of social contacts as compared to participants with high levels of perceived severity after controlling for other variables. Furthermore, participants with higher levels of perceived effectiveness of measures and perceived adherence to measures
made fewer contacts. However, the differences were small. Our results highlight the key role of perceived severity on social contact behaviour during a pandemic. Nevertheless, additional
research is required to investigate the impact of public health communication on severity of COVID-19 in terms of changes in social contact behaviour.
Risk Prediction of Death in Inpatient Adults With COVID-19 from Mexico
Authors: Martínez-Vega Ruth Aralí , Jing Wang , Ortega-Villa Ana Maria , Delgado-Cuellar Oscar Manuel , Hernández-Hernández Victor Alonso , Jan-Gómez Julio Cesar , Rincón-León Héctor Armando , Constantino-Santiesteban Paul , García-Guerra Mariana Piedad , Cetina-Díaz José Hiram , Pérez-Tirado José Manuel , Gómez-Cruz Omar , Amaya-Larios Irma Yvonne , Ramos-Castañeda Jose , Jesús Sepúlveda-Delgado
Published: November 2021

Background

There is substantial variation in COVID-19 lethality across countries. In addition, in countries with populations with extreme economic inequalities, such as Mexico, there are regional and local differences in risk factors for COVID-19 death. The goal of this study was to test the hypothesis that the risk of death in Mexican COVID-19 patients was associated with the time between symptom onset and hospitalization and/or with the healthcare site. Also, death prognostic models were developed.
Methods

The study included two COVID-19 inpatient cohorts, one prospective and one retrospective from Chiapas, Mexico. Demographic, clinical and laboratory variables were collected, and the diagnosis of SARS-CoV-2 infection was performed using RT-qPCR in samples collected seven days since symptom onset. The 30-day mortality, since symptom onset, was the outcome, and clinical variables at the first 48 hours of hospitalization were independent factors. Multivariate logistic regression analyses were conducted.
Results

Of the 392 patients included, 233 died (59.4%). The time between symptom onset and hospitalization, the healthcare site and sex were not related to the 30-day mortality. Three death prognostic models were developed (AUC between 0.726 and 0.807). Age, LDH, AST, and lymphocyte count were included in all models, OSI-WHO Classification (Non-invasive ventilation or high-flow oxygen, and mechanical ventilation with or without organ support/ECMO) and leukocyte count in two models, and diabetes and diarrhea in one model.
Conclusion

The population evaluated had underlying deteriorated health before COVID-19 compared with regional and country population. The factors that determine the COVID-19 mortality risk in a relatively healthy population are sex, age and comorbidities. However, as this study shows, when populations have underlying poor health, some of these factors lose their associations with mortality risk, and others become more important.
Cellular Damage After Prolonged Low-Dose Exposure of Neonicotinoid in Rats
Authors: Naseer Rahat , Tariq Affan , Mirza Munazza Raza , Rashid Muhammad , Raza Syed Qasim , Rajput Sajid Ali
Published: November 2021

Background; Dinotefuran is a new class of neonicotinoids claimed to be harmless to mammals and humans. This claim was daunted by the documented effect of dinotefuran on honeybees and further studies were required. Aim: The study was designed to assess the capaciousness of damage caused by prolonged exposure of dinotefuran in mammals and probable strategy to neutralize its effect. Methodology: Ninety-day trial using Wistar rats (n=45) was conducted while dividing them into three groups: untreated control group, insecticide (dinotefuran) treated group, and dinotefuran treated and vitamin E supplemented group. Dinotefuran was administrated orally (LD25). Vitamin E (alpha-tocopherol) supplementation was given in water ad libitum. Blood sampling was done twice a month, and hematological and biochemical data were recorded. After expiry of trial period, the experimental rats were anesthetized and sacrificed. Organs (kidneys, liver, and heart) were isolated from each groups, weighed, and stored at approximately -20°C till further processing, analysis and histopathology were performed. Results: All the hematological parameters were affected significantly. Histopathology of tissues showed clear necrosis in all the tissues except kidneys. All the biomarkers of oxidative stress and comet assay demonstrated significant cell damage. All the parameters showed improvement after vitamin E supplementation but non-significantly. Significance: These findings were suggestive that even low dose persistent exposure can lead to mutagenicity and carcinogenicity in mammals and other non-target species hence revised policy guidelines and more intelligent use of these chemicals is required.
Evaluation of the inhibitory potential of essential oils and aromatic extracts on SARS-CoV-2 Mpro and PLpro
Authors: Strub Daniel , Talma Michał , Strub Maria , Rut Wioletta , Żmudziński Mikołaj , Brud Władysław , Zhang Linlin , Sun Xinyuanyuan , Lv Zongyang , Nayak Digant , Olsen Shaun , Hilgenfeld Rolf , Drag Marcin
Published: November 2021

Essential oils and aromatic extracts (oleoresins, absolutes, concretes, resinoids) are often used as food flavorings and constituents of fragrance compositions. The flavor and fragrance industry observes significant growth in sales of some natural materials during the COVID-19 outbreak. Some companies worldwide are making false claims regarding their essential oils or blends to be effective (or indirectly points towards this conclusion) against coronaviruses even though the available data on the activity of plant materials against highly pathogenic human coronaviruses is very scarce. Our exploratory study aimed to develop pioneering knowledge, and provide the first experimental results on the inhibitory properties of hundreds of flavor & fragrance materials against SARS-CoV-2 main- and papain-like proteases. As essential oils are volatile products, they could provide an interesting subsidiary inhalation therapeutic strategy in the long term.
Use of composite materials in shipbuilding. Utility and necessity
Authors: G. Samoilescu
Published: November 2021

The paper analyses the characteristics of composite materials and makes a comparison with those commonly used in shipbuilding and on board equipment. The necessity to use composite materials at the expense of classical ones is presented, also taking into account the requirements of the ship's crew and shipowner. Analysis is carried out and practical proposals are made for the use of these materials on the ship's body and on mechanical and electrical equipment.
Modern communication systems concerning future evolution of maritime safety
Authors: GEORGI D
Published: November 2021

Thе Globаl Mаritimе Distrеss аnd Sаfеty Systеm (GMDSS), wаs а mаjor chаngе to thе intеrnаtionаl rеquirеmеnts govеrning thе usе of rаdio by ships аt sеа. Thе nеw tеchniquе of digitаl sеlеctivе cаlling wаs аn еffort to аutomаtе thе wаtch on thе tеrrеstriаl mаritimе bаnds, High Frеquеncy (HF), Mеdium Frеquеncy (MF) аnd Vеry High Frеquеncy (VHF) in ordеr to providе stаblе communicаtions by еliminаting thе voicе rаdio. Thе sаtеllitе ЕPIRB systеm аlеrts hаvе suffеrеd numеrous еfforts to vаlidаtе signаls bеforе lаunching rеscuе boаts аnd аircrаft. Inmаrsаt migrаtеs thе GMDSS Sеrvicеs from thе I-3 sаtеllitе constеllаtion to thе I-4 sаtеllitе constеllаtion. During this procеss а mаnuаl intеrvеntion of thе mobilе еаrth stаtions might bе nеcеssаry. Аftеr thаt thе covеrаgе аrеаs of thе GMDSS sеrvicеs will chаngе. This pаpеr discussеs thе еxpеctеd еvolution of thе communicаtion sеrvicеs in GMDSS, with rеgаrd to sаfеty improvеmеnt, hаving in mind thе countlеss cаsеs of fаlsе аlеrting, аs wеll аs rеgistеrеd distrеss situаtions аnd criticаl еvеnts in thе Blаck Sеа rеgion. А systеmаtic procеss will bе nееdеd to modify thе GMDSS to еnsurе it will rеmаin modеrn аnd fully rеsponsivе to chаngеs in thе rеquirеmеnts аnd еvolution of tеchnology. It is nеcеssаry to еnsurе thаt mаn-mаchinе-intеrfаcе аnd thе humаn еlеmеnt will bе tаkеn into аccount. Thе communicаtions аnd informаtion аrе indispеnsаblе pаrt of mаritimе аnd inlаnd shipping, аnd undoubtеdly bеlong to thе fаmily of front еnd tеchnologiеs. Nеw аnd substаntiаl finаl dеcisions of WRC 15, аs wеll аs dеcisions of othеr orgаnizаtions, concеrning thе following: Chаnnеlizing in Аppеndix 18 of thе Rаdio Rеgulаtions, tеchnicаl chаrаctеristics likе modulаtion аnd coding schеmеs, thе bеnеfits from tеrrеstriаl аnd sаtеllitе pаrts of VDЕS, its usаgе in VTS, GMDSS, е-nаvigаtion, inlаnd shipping, аnd its potеntiаl in sеаrch аnd rеscuе аctivitiеs аrе dеscribеd
Increase of the crew’s well-being and reduction of stress
Authors: D. Georgieva
Published: November 2021

In 2017-2018 the International Marine Organization (IMO) puts in foreground the increase of well-being and mental health of the crew. The goal of the current scientific message is to represent the peculiarities and specifics of the marine profession, the stress factors and their negative effect on health, and the measures of prevention and dealing with stress. The members of the crew are exposed to a variety of predicaments that occur from the specifics of working in marine environment. The disturbing trends in the increasing number of the seafarers, who are affected by the negative aftermath of stress in the last few years, imposes the necessity of undertaking a number of real actions by employers. The lack of a doctor and psychologist on the ships imposes the necessity of performing a number of actions, which guarantee the health, and both the physical and mental safety of the seafarers. The prevention, preliminary training and courses need to be directed to maximal awareness and encouraging the use of the developed specialized programs for well-being, recognizance of the first mental changes in seafarers, the ways of help and self-help, forming and developing social and emotional intelligence. The investment in people’s well-being would surely provide a competitive advantage in the shipping company, and give a direct impact in both turnover, and career perspective of young people who have chosen one of the most difficult and dangerous, but significant occupations.
A parametric study for static deflections of symmetrically laminated rectangular thin plates
Authors: E. Altunsaray
Published: November 2021

This study focuses on static deflection analysis of uniformly lateral loaded composite thin rectangular plate with uniformly lateral loads. Stacking sequence of symmetrically laminated quasi-isotropic plates has the sequence of the orientation angles -45°, 0°, +45°, 90°. Boundary conditions were selected as clamped and simply supported hinges at the edges of the plates. The Finite Difference Method (FDM) was used to determine the maximum deflection of the plates based on the governing differential equations of Classical Laminated Plate Theory (CLPT). Effect of the lamination type, boundary condition and aspect ratio (a/b, b/a) on maximum deflections was investigated parametrically, which are of importance in preliminary design phase of composite plates. Results obtained were compared with those of the Finite Element Method (FEM) received from literature. It was found out that the both groups of the results agree on.
On the technological and dimensional considerations for generating parts by 3D-printed with light processing focus
Authors: M. D. Vasilescu
Published: November 2021

The paper takes into account the specific process of generation and parameters setting of 3D printing process DLP (Digital Light Processing) which have an influence on the characteristics of planar surface of the parts. In the first part of the paper the study is conduct to determinate the parameters which can influence the process of implementation of flat surfaces pieces with 3D DLP process printing. In this part there is and a comparison with the method of generating the marker method 3D printing FDM (Fuse Deposit Modelling). It has chosen this solution because on the one hand the cost of parts are medium, as well as generating principle is relatively simple in terms of technological point of view, but as well as the accuracy and quality of surface generation made with this printing is much better than that provided by the process of asking for a comparison is made. Analysis of the surface will be done so about using an optical microscope with a magnification of 0-500 times, and by means of an electronic measure for dimensional parts as well as for spatial areas of the deviations generated. In it also make references to the methodology of generating flat surfaces and to influence the way their generation characteristics of the parts generated by the 3D printing process type DLP. It should be pointed out that from the perspective of the characteristics of the surfaces generated in literature there are few references in this direction being those areas indicated in the area, as well as acting, although the products have engineering applications.
A new design proposal and thermal analysis of subassemblies inside a satellite
Authors: S. Drăghici
Published: November 2021

On this study the authors aim to validate the use of CFRP composites in a subassembly of a satellite as a replacement for currently used aluminum. Considering the high costs of sending a mass unit of payload into orbit, the mass should be minimized. Therefore, the application of composite materials in electronics housing structures was proposed. For this, a new design is proposed and a comparative thermal analysis of the two boxes is made. Present study focusses on a subassembly’s surfaces and materials of a satellite structure subject to thermal variations in order to numerricaly validate the new design. A satellite electronic housing was subject to a three-dimensional finite element analysis. The satellite’s thermal loading in an orbit of sun-tracking mode are partially transfered to the electronic housing inside. A model is developed and the temperature distribution in the satellite subassembly predicted using empirical available data. Based on the numerical results conclusion and discutions are drawn.
Analysis of gas flows in ships turbines
Authors: V. Aftaniuk
Published: November 2021

In this paper comparison was made of an experimental study of gas flows and CFD simulation of turbine blades steam turbines for ships. For CFD simulation develop solid models, samples were taken from three blades similarly studied in the experiment. An analysis of experimental data and CFD simulation results of the gas flow near lattice the considered type shows the inappropriateness of their application at supersonic speeds. The calculations performed on the CFD model show that the use of CFD modelling methods allows, at the early stages of designing turbine blades, to select the most optimal (in terms of energy losses) forms of profiles for specific modes of operation of the ship's turbine. Further improvement of the profiles that have passed the preliminary calculation check is advisable to conduct on the basis of more detailed experimental tests to obtain dependences of losses in the lattice, the exit angle of the flow from the parameters of the lattice and the angle of gas flow.
ECO SENSITIVE ZONE: A COMMUNITYS PERSPECTIVE ON CHALLENGES AND OPPORTUNITIES FOR SUSTAINABLE TOURISM DEVELOPMENT IN GANGOTRI REGION OF UTTARAKHAND
Authors:   Lecturer, Sri Guru Ram Rai Public School, Patel Nagar, Dehradun, Uttarakhand.India., Kukreti Jyotsna , Upreti Pallavi ,   Assistant Professor,Department of Geography, S.D.M. PG Govt. College, Dehradun, Uttarakhand, India., Singh Rani ,   Assitant Professor, Dept. of Geography, Subodh (Autonomous) P.G. College, Jaipur, Rajasthan, India.
Published: November 2021

The unique ecosystem of the Himalayas with its pristine natural beauty has long been home to endless charms and fascinations attracting tourist from across the world. With resources to support sprawling tourism industry the Himalayas have become one of the most visited tourist regions both in terms of Leisure as well as spiritual tourism. Over the years the booming tourism industry has its share in degrading the fragile mountain ecosystem. Recognizing the potential of tourism to foster socio economic growth and to maintain the local environment, the concept of sustainable tourism has come into place. Being ecologically rich and vulnerable at the same time the development of tourism industry in the Himalayan region must thrive within the ambit of natures limitations. Declaring several ecological rich and vulnerable areas in Uttarakhand to be Eco sensitive zones has redefined not only the type, intensity, exclusivity and inclusivity of tourism activities but also redefined the overall role of tourism in ensuring long term sustainability and viability in such areas. A compendium of communitys perspective on challenges and opportunities in Gangotri Eco sensitive zone in Himalayan state of Uttarakhand India has been presented in the paper. The potential impact on local people, economy and tourism industry itself, post designating popular tourist destination Bhagirathi Valley in Uttarkashi, Uttarakhand as Eco sensitive zone has been highlighted. Perception of people on various dimensions of sustainable tourism which can potentially thrive within the Eco sensitive zone balancing both the mountain ecosystem as well as local economy have also be assessed highlighting the need of sustainable tourism practices in such fragile mountainous regions.
THE PREVALENCE AND RISK FACTORS ASSOCIATED WITH TYPE 2 DIABETIC RETINOPATHY IN RWANDA
Authors:   University of Rwanda, School of Medicine and Pharmacy, Department of Clinical Biology, Huye, Rwanda., Niyodusenga A. ,   University of Nairobi, School of Medicine, Department of Medical Physiology, Nairobi, Kenya., Kiama T.N. ,   University of Nairobi, School of Medicine, Department of Medical Physiology, Nairobi, Kenya., Muhizi C. ,   University of Rwanda, School of Medicine and Pharmacy, Department of Surgery, Huye, Rwanda., Bukachi F. ,   University of Nairobi, School of Medicine, Department of Medical Physiology, Nairobi, Kenya.
Published: November 2021

Objective: To determine the prevalence and risk factors associated with type 2 diabetic retinopathy in Rwanda. Methods: A case-control study was conducted from January to September 2019 in four hospitals within the Republic of Rwanda. Type 2 diabetic patients were screened for retinopathy. Patients with retinopathy were considered as cases and those without retinopathy as controls. A study sample of 592 participants were enrolled, 66 cases and 526 controls. Diabetic retinopathy was assessed by indirect ophthalmoscopy performed for each eye with a slit-lamp +90D lens. Plasma glucose and Glycated hemoglobin (HbA1c) were measured by colorimetric enzymatic tests. Albuminuria was measured by quantitative spectrophotometric method. Triglycerides, Total, HDL and LDL cholesterol, Urea and Creatinine were assayed by colorimetric methods. A questionnaire was used to assess medical history and demographic status. Data were analyzed by use of SPSS version 20. Statistical analyses were performed by Chi square to show association between nominal and ordinal data. Multivariate logistic regression analysis to select independent variables was performed. Odds ratio was used as a measure of association. Results: The prevalence of diabetic retinopathy in this study population was 11.2%. Independent risk factors associated with diabetic retinopathy were long duration of diabetes, hyperglycemia, LDL cholesterol, triglycerides, and albuminuria. Conclusion: The prevalence of diabetic retinopathy is high and is associated with traditional modifiable risk factors. Early detection and management of diabetes mellitus and these risk factors, combined with good adherence to scheduled eye examination would greatly improve the quality of life of affected patients.
A STUDY OF CARDIAC MANIFESTATIONS IN PATIENTS WITH HIV/AIDS
Authors:   Senior Resident, Department of Medicine, Shri Vasantrao Naik Government Medical College, Yavatmal., Bang Ajay , Deshmukh Deepti ,   Associate professor, Department of Medicine, Indira Gandhi Government Medical College, Nagpur., Raut Sanjay ,   Associate Professor, Department of Medicine, Government Medical College, Gondia.
Published: November 2021

Introduction:HIV/AIDS pandemic is evolving as a major public concern. Cardiovascular diseases are common in HIV-positive patients. Many patients without any symptoms or signs were found to have a cardiovascular disease on autopsy.It is expected that the risk of cardiovascular disease willrise in the following years due to the cardiovascular risk profile andincreased life expectancy of infected patients. Therefore,diagnosis andtherapy of HIV-associated cardiovascular diseases should be part of the evaluation and management of the HIV-positive patient. Objectives: To find out the frequency of cardiac manifestations on clinical examination, electrocardiography, chest X-ray, and echocardiographic examination. To assess the association of Cardiac abnormality with CD4 Count in patients with HIV/AIDS. Toevaluate the association between cardiac abnormalities with types and duration of antiretroviral therapy regimen (ART). Method:A total of 100 consecutive patients visiting ART OPD and admitted to our institute were examined for signs and symptoms of cardiovascular disease. All patients were evaluated with electrocardiography, chest X-ray, and 2 D echocardiography. CD4 count was measured for all patients using flowcytometry using a BD FACS Count system. Results:Out of 100 patients, 53% were male and 47% were female. Patients were divided into subgroups with CD4 count <200, 200-349, 350-499, and â‰¥500. The mean CD4 count was 403.62 Â± 284.98. Prevalence of the cardiovascular abnormality on ECG, chest X-ray, and echocardiography were 74%, 10%, and 51% respectively. The left ventricular systolic dysfunction was the most common finding in our study with fractional shortening â‰¤25% in 34% of patients and LVEF <50% in 27% of patients followed by left ventricular diastolic function (26%), dilated cardiomyopathy (6%), pulmonary hypertension (4%), and regional wall motion abnormality (2%).Reduced LV ejection fraction (<50%) and left ventricular diastolic dysfunction were statistically significant in patients with CD4 count less than 200/mm3. Conclusion: In present study electrocardiographic, chest X-ray and echocardiographic abnormalities were present in 74%, 10% and 51% patients respectively. Cardiac abnormalities such as QTc prolongation, LBBB, reduced left ventricular ejection fraction, and left ventricular diastolic dysfunction were more significantly higher in patients with CD4 count less than 200/mm3. We could not find any statistically significant difference in cardiac abnormalities in patients on different ART regimens. Further studies are required with a higher sample size.
RELATIONSHIP OF MEAN PLATELET VOLUME WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND ITS SEVERITY- AN OBSERVATIONAL STUDY
Authors: Kumar Sharma Kishore , Ram Kumhar Mani , Shrivastav Mayank , Tak Harsh
Published: November 2021

Background & Objectives: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation and inflammation. Mean platelet volume (MPV) may be used as a marker of inflammation. We aimed to study the association between MPV and COPD patients during acute attack and relationship of MPV with severity of COPD by FEV1 (%predicted), BODE Index, PaO2, mMRC grade and 6MWD test. Methods: 100 patients with COPD (50 with acute exacerbation and 50 with stable COPD) and 30 healthy controls were enrolled in the study. Mean platelet volume (MPV), spirometry, arterial blood gases, body mass index, renal function tests and BODE index (body mass index, airflow obstruction,dyspnoea and exercise) were assessed. Level of MPV was compared between cases and controls. Results: Of 100 COPD patients, 87(87%) were male and 13(13%)were female.MPV was significantly higher in COPD patients than control and also higher in acute exacerbation group than stable COPD (p=0.001). Interpretation & Conclusions: In the present study,MPV remain in normal range in all COPD patients, but MPV values were significantly higher in COPD cases compared with control.Increased MPV was associated with acute exacerbation and also increasing with severity of COPD.
LEIOMYOMA TYPES, INCIDENCE AND CLINICAL PRESENTATION - A STUDY AT A TERTIARY CARE HOSPITAL
Authors:   Malla Reddy Institute of Medical Sciences, Hyderabad., Sujatha Ragoor , Jayasheela Mary ,   Malla Reddy Institute of Medical Sciences, Hyderabad., Bhavani Karuna ,   Malla Reddy Institute of Medical Sciences, Hyderabad.
Published: November 2021

A cross sectional studywas conducted over a period of 15 months from 1st Jan 2020 to 31st March 2021 at Malla Reddy Hospital,a tertiary care hospital. To study the incidence of fibroids according to FIGO categorization and their clinical presentation. 38 confirmed cases of fibroid uterus in the age group 20 Ã¢Â€Â“ 60 attending gynecology OPD were interviewed and subjected to regular gynecological examination, PAP smear, dilatation and curettage procedures. Based on the studies, 60% of these patients were subjected to total abdominal hysterectomy as a part of treatment and the intra operative findings of the specimens were noted. The leiomyomas were classified according to the histopathological and ultrasonographic findings based on FIGO categorization. Highest incidence was seen 41 to 45 years age (52.6%). Incidence of Leiomyoma types according to FIGO subclassification system were found to be Type0=5%, Type1=5%, Type2=5%, Type3=13%, Type4=30%, Type5=13%, Type6=18.6%, Type7=3.3% and Type8=5%. Multiple fibroids were more common than single fibroids. Posterior location fibroids were more common than anterior. Most common symptom was menorrhagia (73.6%) followed by spasmodic dysmenorrhea (47.3%) and metrorrhagia (26.3%), infertility and symptoms of anemia. Most common sign was pallor (58%) followed by mass per abdomen (18.4%). Incidence of associated pathology of adenomyosis (18%) ovarian cysts (8%), endometrial polyps (8%), myxoid degeneration (2.6%). The results of our study matched the existing studies.
A personality-based behavioural model: Susceptibility to phishing on social networking sites
Authors:   , Frauenstein Edwin Donald
Published: November 2021

The worldwide popularity of social networking sites (SNSs) and the technical features they offer users have created many opportunities for malicious individuals to exploit the behavioral tendencies of their users via social engineering tactics. The self-representation and social interactions on SNSs encourage users to reveal their personalities in a way which characterises their behaviour. Frequent engagement on SNSs may also reinforce the performance of certain activities, such as sharing and clicking on links, at a “habitual” level on these sites. Subsequently, this may also influence users to overlook phishing posts and messages on SNSs and thus not apply sufficient cognitive effort in their decision-making. As users do not expect phishing threats on these sites, they may become accustomed to behaving in this manner which may consequently put them at risk of such attacks. Using an online survey, primary data was collected from 215 final-year undergraduate students. Employing structural equation modelling techniques, the associations between the Big Five personality traits, habits and information processing were examined with the aim to identify users susceptible to phishing on SNSs. Moreover, other behavioural factors such as social norms, computer self-efficacy and perceived risk were examined in terms of their influence on phishing susceptibility. The results of the analysis revealed the following key findings: 1) users with the personality traits of extraversion, agreeableness and neuroticism are more likely to perform habitual behaviour, while conscientious users are least likely; 2) users who perform certain behaviours out of habit are directly susceptible to phishing attacks; 3) users who behave out of habit are likely to apply a heuristic mode of processing and are therefore more susceptible to phishing attacks on SNSs than those who apply systematic processing; 4) users with higher computer self-efficacy are less susceptible to phishing; and 5) users who are influenced by social norms are at greater risk of phishing. This study makes a contribution to scholarship and to practice, as it is the first empirical study to investigate, in one comprehensive model, the relationship between personality traits, habit and their effect on information processing which may influence susceptibility to phishing on SNSs. The findings of this study may assist organisations in the customisation of an individual anti-phishing training programme to target specific dispositional factors in vulnerable users. By using a similar instrument to the one used in this study, pre-assessments could determine and classify certain risk profiles that make users vulnerable to phishing attacks.
Features of cough therapy in children
Authors: Kholodova I. N.
Published: November 2021

This article discusses the problem of cough in children as one of the symptoms of a complicated course of acute respiratory infection. The data on the peculiarities of the course of cough in children depending on the cause, the level of damage, and age are presented. Virulence of infectious agents, immune status, and the child’s constitution may influence the development of local inflammation covering the tonsils, adenoids, pharynx, larynx. The study of respiratory problems in children remains relevant due to the need to improve therapy tactics and rehabilitation after an infection. Acute upper respiratory tract infections affect about 23 million children annually, which is 52% of the total morbidity of children and adolescents aged 0-17 years. Various therapeutic options are discussed. Thus, central drugs have a direct antitussive effect and cause inhibition of the cough center: narcotic antitussive drugs, such as codeine-containing drugs; non-narcotic antitussive drugs (glaucine hydrochloride, butamirate citrate, etc.). Peripheral medications reduce the sensitivity of cough afferent receptors and act on the mucosa of the airways. There are drugs of combined action, as well as bronchodilators, mucoactive drugs, and chest cough sets. Particular attention is paid to the multicomponent drug, which has a complex anti-inflammatory, antitussive and antimicrobial action in cough. The results of various foreign and domestic studies on the efficacy and safety of this drug are given. The necessity of early treatment is emphasized to improve the quality of life of patients and to prevent the formation of chronic bronchial processes. It is concluded that for the treatment of children it is necessary to choose the best drugs. It should be drugs that have proven efficacy and safety, and most importantly - they should be registered for use in the Russian Federation.
Immunoprophylaxis of influenza, acute and recurrent respiratory infections during the COVID-19 pandemic
Authors: Girina A. A. , Zaplatnikov A. L. , Burtseva E. I. , Svintsitskaya V. I. , Maykova I. D. , Dubovets N. F. , Koroid N. V. , Lepiseva I. V. , Voskanyan A. Е. , Tkacheva D. N. , Panova A. D. , Motorny S. A.
Published: November 2021

The article notes features of the last epidemic season (2020-2021) in the form of extremely low activity of influenza viruses with SARS-CoV-2 remaining dominant in the etiological structure of acute respiratory viral infections. Presented own data indicating the heterogeneity of SARS-CoV-2 (Alpha, Delta, B.1.1.317, B.1.1.397, B.1.1.523) isolated from hospitalized patients was noted. An increase in the etiological role of bocavirus, alpha-coronavirus and metapneumovirus with a decrease in the frequency of parainfluenza viruses, adenoviruses, rhinoviruses and respiratory syncytial virus was established. An unusual shift of the period of maximum activity of respiratory syncytial virus to the 20th week was noted. Attention is paid to the need during the ongoing pandemic COVID-19 to fully immunize children as part of the National Immunization Calendar, also emphasized the role of mandatory annual vaccination against influenza. It is noted that the maximum protective effect of immunoprophylaxis of influenza acute and recurrent respiratory infections can be achieved with a combination of vaccination with bacterial lysates. The article presents a review of the literature and our data demonstrating the safety, good tolerability, and high clinical and immunological efficiency of polyvalent mechanical bacterial lysate for the prevention of acute and recurrent respiratory infections in children. It is shown that the use of polyvalent mechanical bacterial lysate during the prevaccination period makes it possible to substantially reduce the frequency of intercurrent infections, which reduces the number of temporary medical withdrawals and increases the coverage of vaccinations against influenza in organized groups to 85.1%. The role of trained immunity as one of the possible mechanisms providing nonspecific immunoprophylaxis during influenza vaccination and the use of bacterial lysates is discussed.