Mechanical Properties and Microstructure Evolution of Cemented Tailings Backfill Under Seepage Pressure

Cemented tailing backfill (CTB) in underground mine inevitably experiences seepage field, which complicates its mechanical behavior. In this study, the mechanical properties and microstructure characteristics of CTB under different seepage water pressures (SWPs) were investigated. The results show that, with the increase in SWP, the mechanical properties of CTB decrease, but the decreasing trend reduces gradually. Higher SWP leads the microstructure of CTB looser and more porous, and the largest proportion of pores initiated and propagated by SWP is micropores, which means the damage in CTB under seepage is mostly caused by micropores. Besides, the mechanical properties of CTB under seepage decrease exponentially with the increase in porosity and present linearly inverse proportional relation to the pore area fractal dimension. Results above indicate that SWP has a significant deterioration effect on the mechanical properties and microstructure of CTB. The research could not only extend the knowledge of mechanical properties and microstructure characteristics of CTB under seepage but also provide a theoretical reference for mechanical index determination and stability analysis of CTB in water-rich underground mines.

Field changes on automated Humphrey’s field analyzer in tuberculosis following ethambutol therapy

This study was conducted to evaluate the visual field changes in tubercular patients on anti-tubercular therapy and to assess the reversibility of these changes after the discontinuation therapy. This study was conducted as a prospective analytical study at tertiary care centres in Bhopal and Jabalpur on all newly detected tuberculosis patients. Ocular history, relevant history was recorded and detailed ocular examination was done at the time of presentation, before initiating ATT. All the patients were followed up periodically till the cessation of treatment and three months thereafter. A total of 40 cases of newly diagnosed tuberculosis were registered with mean age of 38.4±13.99 years. We documented significant deterioration in visual acuity after 3 months of initiation of therapy. Once the ATT was stopped, the improvement in visual acuity was statistically significant 3 months after the cessation of ATT as compared to visual acuity 3 months after initiation of ATT (p<0.05). But residual visual impairment even after stoppage of ATT was observed. Color vison and visual field defects were observed in higher proportions of eyes following initiation of ethambutol which improved significantly after 3 months of cessation of ATT (p<0.05). Ethambutol, even in recommended dose according to DOTS, has been associated with ocular toxicity which manifests in the form of painless progressive loss of vision, color vision defects and visual field defects. Though these changes are usually reversible, few patients have irreversible damage. Thus, patients receiving ethambutol must be explained regarding these effects and followed up periodically.

The role of computed tomography in the diagnosis of lung cancer - a case report

Introduction Lung cancer has been the main oncological problem in the world for years. It is extremely important to use appropriate diagnostic methods that enable its detection and implementation of appropriate treatment. Aim The presented case shows the advantage of computed tomography over chest X-ray (X-ray) in visualizing neoplastic changes in the lungs. Case Study The paper presents a description of a patient diagnosed with centrally located advanced lung adenocarcinoma with a strong expression of PD-L1 qualified for treatment with pembrolizumab. Results and Discussion Presented case confirms that X-ray is less sensitive, especially in the case of centrally located tumors. Therefore, the emergence of a new cough in a smoker or ex-smoker should raise concerns related to lung cancer despite a normal X-ray image. The central location of the tumor may cause dramatic course of the symptoms. In the presented case, a sudden significant deterioration of the condition was observed due to atelectasis of the entire lung. Haemoptysis observed during hospitalization was another symptom of centraly located tumor mass. Conclusions In conclusion, the history of cigarette smoking, presence of typical symptoms should provide an in-depth diagnosis of lung cancer, despite normal X-ray. Diagnostic procedures include computed tomography in the first place. The course of centrally localized disease may change rapidly during on first cycle of treatment. Due to the possibility of serious complications of the ongoing neoplastic disease, the patient should be under constant medical supervision.

Cognitive functions of young Novosibirsk residents and metabolic syndrome

The aim of the study was to provide a population assessment of cognitive impairment patterns in a representative sample of 25–44-year-old men and women living in Western Siberia with metabolic syndrome (MS). Material and methods. A cross-sectional population survey of a random representative sample of 25–44-year-olds of both sexes (1503 people) permanently residing in Western Siberia (Novosibirsk) was performed. The study of cognitive functions was conducted in 1009 people: 463 men (45.9 %) and 546 women (54.1 %). A 10-word memorization test was performed according to the methodology proposed by A.R. Luria (unified for screening purposes), with subsequent reproduction after interfering tasks (recall), a proof-reading test (a letter modification of the Bourdon test used for screening purposes), as well as the exclusion of concepts (a verbal version of the test). The MS criteria (VNOK, 2009) were used: FROM > 80 cm in women and > 94 cm in men and 2 of the following criteria: blood pressure ≥ 130/85 mmHg, TG content ≥ 1.7 mmol/L, HDL-C < 1.0 mmol/L in men and < 1.2 mmol/L in women, LDL-C > 3.0 mmol/L, plasma hyperglycemia > 6.1 mmol/L. Results. In the surveyed sample of residents of In Novosibirsk, 25–44 years old, MS occurred in every fourth person tested for cognitive functions (26.06 %): 148 men (31.96 %) and 115 women (21.06 %), MS occurred more often in women than in men. With age, there is an increase in the frequency of MS in both sexes (p < 0.05). For MS, statistically significant associations are shown with direct memorization (1st memorization experience, p = 0.025), the number of directly memorized words (p = 0.015) and with delayed reproduction of words after an interfering task (p = 0.015) in the 10-word memorization test by A.R. Luria. The average rank, as well as the average values of these cognitive tests, were higher in individuals without MS compared to those with MS diagnosed. There were no links between MS and the indicators of the proofreading test. There were also no statistically significant associations of MS with the number of animals named in 1 min in the speech activity test when studying semantically mediated associations. Conclusion. In a population study of young people (25–44 years old) for the first time in Russia/A statistically significant deterioration of cognitive memory patterns in individuals with MS components has been proven in Siberia (Novosibirsk). This confirms the importance of the «cerebrovascular continuum» in the genesis of cognitive impairment at a young age.

Methodological Foundations of Renewal and Expansion of Car Fleet

Currently, Russian international road transport carriers do not have sufficient potential to successfully compete with their foreign partners. The main reasons for this are significant deterioration of the car fleet and its non-compliance to modern environmental requirements, lack of own funds for timely renovation and development of the motor transport fleet, as well as systemic lag in development of transportation technologies and their logistics support.The objective of the article is to substantiate the choice of rational measures to solve the problem of expanded reproduction of car fleet used in international road haulage. The methodology used in preparation of the article is based on the use of general scientific methods in combination with special methods, including the analysis of statistical data on international road haulage, a comparative analysis of the state of the car fleet of Russian carriers, considering the basic conditions and operational characteristics, classification of the fleet of trucks based on typification of their operational characteristics with subsequent subdivision of this fleet into three main groups, an overview analysis and benchmarking of foreign operating experience and future development of car fleet, an analysis of the economic and legal possibilities of raising funds for renewal of car fleet.The article examines and studies: a) urgency of solving the problem of renewal and expansion of the car fleet used by Russian carriers in international road transportation; b) foreign experience and trends in development of fleet used for international haulage; c) the main directions of providing economic opportunities for transition to expanded renewal of vehicles; d) analysis of the legal possibilities of providing public support for expanded reproduction of the motor transport fleet of Russian international road carriers including through the use of public-private partnerships.Based on the results of the study, proposals have been developed aimed at ensuring renewal and expansion of car fleet and increasing the efficiency of international road haulage operations.

Exploring the Quality of Life Related to Health and Vision in a Group of Patients with Diabetic Retinopathy

(1) Background: Visual impairment of people with diabetic retinopathy (DR) and its high impact on different dimensions of their lives can cause a significant deterioration in the quality of life. The aim of this study was to examine the association and relationship between quality of life related to vision and the relevant clinical and sociodemographic variables in a group of patients with DR in Spain. (2) Methods: A descriptive cross-sectional study was conducted in all patients with DR over 18 years under follow-up in the Retina Service of the University Hospital of Burgos (HUBU), recruited during the months of January and February 2020. The main study variable was quality of life related to health and vision, obtained using the National Eye Institute Visual Function Questionnaire 25 (NEI-VFQ-25). (3) Results: In total 87 participants made up the sample, and significant differences were found in the NEI-VFQ-25 according to gender, type of diabetes, episodes of decompensated diabetes and high blood pressure (HBP) (p < 0.05). Best-corrected visual acuity (BCVA) was also correlated with the NEI-VFQ-25 (p < 0.05). (4) Conclusions: These data could facilitate the design of action protocols focused on the well-being of the patient, in addition to considering the clinical characteristics. Further studies are needed to help understand the causal relationship between variables and that includes a wider variety of factors.

The Mediating Role of Resilience and Life Satisfaction in the Relationship between Stress and Burnout in Medical Students during the COVID-19 Pandemic

Following the WHO's declaration of a public health emergency due to the COVID-19 outbreak, the subsequent quarantine and confinement measures that were adopted, including distance learning measures, were shown to have caused a significant deterioration in the mental health of medical students. The goal of this study was to explore the mediating role of resilience and life satisfac-tion in the relationship between perceived stress and burnout among medical students in the con-text of COVID-19. A transversal assessment was performed using an online questionnaire, to which 462 students responded. The instruments applied were the Perceived Stress Scale-10, the Resilience Scale-25 items, the Satisfaction with Life Scale (SWLS) and the Burnout Scale (Olden-burg Inventory). A regression model was estimated for each dimension of burnout. The results revealed that resilience and life satisfaction play a mediating role in the association between stress and the dimensions of burnout. This suggests that measures of promoting mental health based on resilience and improving perceptions of life should be implemented.

On the Recycling of Water Atomized Powder and the Effects on Properties of L-PBF Processed 4130 Low-Alloy Steel

The microstructure and mechanical properties of a 4130-grade steel processed by L-PBF using a feedstock of low-cost water atomized powder have been investigated considering the effects of powder recycling. Chemical analysis of the recycled powder showed a constant amount of alloying elements with a slight reduction in oxygen content. The as-built microstructure was mainly composed of a martensitic structure separated by a high fraction of low-angle grain boundaries, suggesting the application of a direct tempering treatment starting from the as-built condition as a cost-effective post-process thermal treatment rather than the conventional quench and tempering treatment. Moreover, the degree of anisotropy generated by L-PBF in as-built specimens could be reduced after performing either the direct tempering or the quench and tempering treatments. The possible degradation of powder properties on the steel performance was also investigated. After various powder recycling events, no significant deterioration in tensile properties was measured, indicating that the water atomized powder could be a sustainable feedstock candidate for L-PBF.

Processing of the Results of Satellite Inland Positioning Transport using Mobile Devices and their Visualization

The issue of spatial data visualization is currently an important element in the positioning and navigation process. The constant trend in increasing the accuracy and availability of position modules affects the widespread use of the mobile devices in transport. The paper presents creation of a three-dimensional visualization model based on ground tracks recorded in NMEA (National Marine Electronics Association) and GPX (GPS Exchange Format) formats. Additionally, the study presents an analysis of the positioning accuracy including the sky obstructions presence and the instantaneous state of the satellite constellation. The significant deterioration in positioning accuracies was noted due to the presence of sky obstructions and low movement speed during data recording. The analysis of these parameters showed the dependence of the positioning accuracy with the number of visible satellites and the HDOP (Horizontal Dilution of Precision) parameter.

New Techniques in Hemorrhoidal Disease but the Same Old Problem: Anal Stenosis

Anal stenosis, which develops as a result of aggressive excisional hemorrhoidectomy, especially with the stoutly use of advanced technologies (LigaSure, Ultrasonic Dissector, Laser, etc.), has become common, causing significant deterioration in the patient's quality of life. Although non-surgical treatment is effective for mild anal stenosis, surgical reconstruction is unavoidable for moderate to severe anal stenosis that causes distressing, severe anal pain, and inability to defecate. The problem in anal stenosis, unlike anal fissure, is that the skin does not stretch as a result of chronic fibrosis due to surgery. Therefore, the application of lateral internal sphincterotomy does not provide satisfactory results in the treatment of anal stenosis. Surgical treatment methods are based on the use of flaps of different shapes and sizes to reconstruct the anal caliber and flexibility. This article aims to review the functional results, postoperative care, and complications of these methods.