Critical Level Research Articles

Features of hematological indices in cataract in the dynamics of surgical treatment

BACKGROUND: Cataract is one of the most common ophthalmologic diseases leading to blindness. AIM: To study the features of hematological indices in men over 40 years old with different types of cataract before and after surgical treatment. MATERIAL AND METHODS: The examination groups included 25 patients (25 eyes) with opacities localized in the cortical substance of the lens, 19 (19 eyes) with total opacities, 26 (26 eyes) with nuclear opacities, 30 (30 eyes) with subcapsular opacities; of these, 43 patients (43 eyes) had initial cataract, 39 (39 eyes) — immature, 18 (18 eyes) — mature cataract. The control group consisted of 30 people. All study participants underwent a complete ophthalmologic examination and assessment of hematological indices. The following integral hematological indices were calculated using generally accepted formulas: lymphocyte index (lymphocytes/neutrophils); leukocyte intoxication index; neutrophil/lymphocyte ratio index; neutrophil/monocyte ratio index; lymphocyte/monocyte ratio index; lymphocyte/eosinophil ratio index; leukocyte ratio and erythrocyte sedimentation rate index. Statistical analysis was performed using the Statistica 10 package. The Kruskal–Wallis and Mann–Whitney nonparametric tests were used to assess differences in the groups. The critical level of statistical significance when testing scientific hypotheses was p 0.05. RESULTS: At all stages of cataract maturity, before and after surgery, unidirectional changes in the hematological indices were revealed: the lymphocyte and eosinophil ratio decreased (1.4–2.0; p=0.01), the neutrophils and monocytes (1.3–2.1; p=0.04), lymphocytes and monocytes (1.4–2.5; p=0.02) ratios, leukocytes and erythrocyte sedimentation rate (2.9–6.8; p=0.01) increased. In immature cataract, the intoxication index according to the hematological indices increased by 2 times in the dynamics of surgical treatment. At the same time, multidirectional changes in the hematological indices were revealed in cortical and subcapsular opacities of the lens, unidirectional changes — in nuclear and total opacities. CONCLUSION: Patients with nuclear and total cataracts have the greatest number of disturbances in the ratio of cell populations according to hematological indices, therefore they constitute a risk group for the development of complications.

Cerebral Infarct Growth: Pathophysiology, Pragmatic Assessment, and Clinical Implications.

Cerebral ischemic injury occurs when blood flow drops below a critical level, resulting in an energy failure. The progressive transformation of hypoperfused viable tissue, the ischemic penumbra, into infarction is a mechanism shared by patients with ischemic stroke if timely reperfusion is not achieved. Yet, the pace at which this transformation occurs, known as the infarct growth rate (IGR), exhibits remarkable heterogeneity among patients, brain regions, and over time, reflecting differences in compensatory collateral flow and ischemic tolerance. We review (1) the pathophysiology of infarct growth, (2) the advantages and pitfalls of different approaches of IGR measurement, (3) research gaps for future studies, and (4) the clinical implications of stroke progressor phenotypes. The estimated average IGR in patients with acute large vessel occlusion stroke is 5.4 mL/h although there is wide variability based on ischemic stroke subtype, occlusion location, presence of collaterals, and patient baseline status. The IGR can be calculated using various pragmatic strategies, mostly either quantifying the extension of the infarct at a particular time and dividing this measure by the time that elapsed from symptom onset to imaging assessment or by using collateral blood flow status as a radiological surrogate marker. The IGR defines a spectrum of clinical stroke phenotypes, often dichotomized into fast and slow progressors. An IGR ≥10 mL/h and the perfusion metric hypoperfusion intensity ratio ≥0.5 are commonly used definitions of fast progressors. A nuanced understanding of the IGR and stroke progressor phenotypes could have clinical implications, including informing prognostication, acute decision-making in peripheral-to-comprehensive transfer patients eligible for thrombectomy, and selection for adjuvant neuroprotective agents.

Microbiota of complete removable dentures

Purpose: to study the quantitative and qualitative composition of microflora on the surface of complete removable dentures after 1 and 4 years of use. Materials and methods: 40 patients were diagnosed with complete edentulism (K08.1) using complete removable acrylic dentures for no more than 4 years were examined. The composition of the microflora was determined by mass spectrometry method. Statistical processing of the results of the study was carried out using the computer package Statistica13. To assess the differences between the groups, parametric t-criteria with Bonferroni correction were used for multiple comparisons, the critical level of statistical significance of p was 0.05. Results: it was found that in 4 years the number of yeast and fungi increased by 91%, n=20 (100%); the number of actinobacteria increased by 61%, n=20 (100%); the number of gram-negative bacteria increased by 500% n=20 (100%); the number of anaerobic microorganisms increased by 50% n=20 (100%); the number of cocci and bacilli increased by 190% n=20 (100%). Conclusion: after conducting the research, we found that after 4 years of using removable dentures n=20 (100%), the number of cocci and bacilli increased from 56±5 (105 cells/gram) (p=0.03) to 107±8 (105 cells/gram) (p=0.04). The number of anaerobes increased n=20 (100%) from 68±6 (105 cells/gram) (p=0.0002) to 102±9 (105 cells/gram) (p=0.0002). The number of actinobacteria n=20 (100%) increased from 30±3 (105 cells/gram) to 143±12 (105 cells/gram) (p=0.003). The number of gram-negative bacteria n=20 (100%) increased from 4±1 (105 cells/gram) (p=0.0005) to 24±2 (105 cells/gram) (p=0.0006). The number of fungi and yeast n=20 (100%) increased from 977±90 (105 cells/gram) (p=0.0003) to 1587±136 (105 cells/gram) (p=0.003).

Threshold Modeling for Antibiotic Stewardship in Oman.

Antimicrobial stewardship supports rational antibiotic use. However, balancing access to antibiotic treatment while controlling resistance is challenging. This research used a threshold logistic modelling approach to identify targets for antibiotic usage associated with carbapenem-resistant Acinetobacter baumannii (CRAb), carbapenem-resistant Klebsiella pneumonia (CRKP), and extended-spectrum β-lactamases- producing Escherichia coli (ESBL-producing E. coli) incidence in hospitals. This study utilises an ecological population-level design. Monthly pathogen cases and antibiotic use were retrospectively determined for inpatients between January 2015 and December 2023. The hospital pharmacy and microbiology information systems were used to obtain this data. Thresholds were identified by applying nonlinear modelling and logistic regression. Incidence rates of 0.199, 0.175, and 0.146 cases/100 occupied bed-days (OBD) for CRAb, CRKP, and ESBL-producing E. coli, respectively, were determined as the cutoff values for high (critical) incidence rates. Thresholds for aminoglycosides (0.59 defined daily dose (DDD)/100 OBD), carbapenems (6.31 DDD/100 OBD), piperacillin-tazobactam (3.71 DDD/100 OBD), third-generation cephalosporins (3.71 DDD/100 OBD), and fluoroquinolones (1.91 DDD/100 OBD), were identified. Exceeding these thresholds would accelerate the gram-negative pathogens' incidence rate above the critical incidence levels. Employing the threshold logistic approach enabled near real-time performance monitoring feedback, risk scores and alert signals for when the incidence of the selected pathogens are entering critical levels. Threshold logistic models can help inform and implement effective antimicrobial stewardship interventions to manage resistance within hospital settings.

Determination of selected oxysterol levels, oxidative stress, and macrophage activation indicators in children and adolescents with familial hypercholesterolemia.

Elevated levels of cholesterol in the bloodstream, also referred to as hypercholesterolemia, pose a significant risk for the onset of cardiovascular and cerebrovascular diseases. Oxysterols, cholesterol-derived oxidized compounds that form enzymatically or non-enzymatically, contribute to the development of atherosclerosis and coronary artery disease. This study aimed to examine the critical oxysterol levels in children and adolescents with hypercholesterolemia and explore the correlation between these levels, oxidative stress, and atherosclerosis progression. The study included 20 patients with familial hypercholesterolemia (FH) and 20 healthy individuals aged between 6 and 18 years. Participants were categorized into children (6-9 years) and adolescents (10-18 years). Pediatric and adolescent patients were selected from among subjects with LDL-C ≥ 130mg/dL and diagnosed with heterozygous familial hypercholesterolemia (HeFH) based on the presence of mutations in the LDL receptor (LDL-R) gene. Patients with HeFH who were receiving regular atorvastatin therapy were included in the study. There were no notable differences in catalase and paraoxonase (PON1) activities among the groups. However, the patient group displayed substantially higher levels of malondialdehyde (MDA) (P = 0.0108) and superoxide dismutase (SOD) activity (P = 0.0103). Compared to the healthy control group, serum chitotriosidase (CHITO) activity (P = 0.037) and chitinase 3-like protein 1 (YKL-40) levels (P = 0.0027) were significantly elevated in the patient group. Furthermore, the carotid intima-media thickness (CIMT) measurements of the patient group were significantly greater than those of the healthy group (**P < 0.0001****). The patient group exhibited significantly elevated levels of 5,6-α-epoxycholesterol, Cholestane-3β,5α,6β-triol (C-triol), and 7-ketocholesterol (7-KC), whereas 27-hydroxycholesterol (27-OHC) was significantly more abundant in the healthy group. On the other hand, while 27-OHC/Total cholesterol (Total-C) levels were significantly higher in healthy individuals, the C-Triol/Total-C ratio was significantly higher in patients. No significant differences were found between the groups in terms of 7-KC/Total-C and 5,6-α-epoxycholesterol/Total-C levels. This study highlights the key roles of oxysterols, oxidative stress, and macrophage activation in the development of atherosclerosis in pediatric and adolescent patients with FH. Elevated C-Triol levels in FH patients, alongside increased CIMT, point to early vascular changes despite atorvastatin therapy. In contrast, higher 27-OHC levels in healthy controls suggest differential oxysterol regulation due to cholesterol-lowering treatments in FH patients. C-Triol and 27-OHC/Total-C ratios showed potential as biomarkers to distinguish patients with FH. These findings emphasize the need for therapies targeting oxidative stress and macrophage activation in addition to cholesterol-lowering interventions.

Quantitative Research on Gifted/Talented Students’ Critical Thinking Skills

This study aims to determine the level of critical thinking skills among gifted students and investigate whether there is a relationship between their levels of critical thinking and their gender, age, grade level, pre-kindergarten education and parents' educational backgrounds. The study sample of the research consists of 203 students who are enrolled in the Science and Art Center in the central district of Kütahya province, Turkey during the 2021-2022 academic year. As per the findings, gifted female students have higher mean scores in the Critical Thinking Dispositions Scale compared to gifted male students. Also, this study examined the differences in critical thinking levels between gifted students who received pre-kindergarten education and those who did not receive pre-kindergarten education. The results indicate that these differences are statistically insignificant. As another remarkable finding, gifted students whose mothers have a high school or Master’s and above education level have significantly higher levels of critical thinking compared to gifted students whose mothers have a primary school or middle school education level.

Calcium Silicate Application as a Salt Stress Mitigation Strategy for Vegetables in the Salt-affected Soils of Sandy Plains of Kerala, India

Soil salinity inhibits plant growth due to osmotic stress and reduced plant and water uptake. In the Onattukara sandy plains of Kerala, saltwater intrusion is a major problem in several panchayaths near the coastal area. In uplands also, cultivation is not possible due to the salt stress from saltwater intrusion. One of the strategies for removing the inhibitory effect of salt stress on plant growth is the application of beneficial nutrients to the plants. Therefore, a study was carried out to understand the effect of calcium silicate application on mitigating salt stress in vegetables and using tomato as a test crop. A detailed germination study was conducted in laboratory conditions prior to pot culture experiment to find out the critical level of salinity for tomato and two salinity levels 30mM and 40 mM NaCl were selected for the pot culture experiment. For accessing the effect of the various levels of calcium silicate on reducing salt stress in tomato, a pot culture experiment was conducted in Onattukara region (AEU 3) in completely randomized design with ten treatments replicated thrice with varying levels of CaSiO3 from 100 kg ha-1 to 150 kg ha-1. The treatments had a significant effect on all the biometric characteristics and yield attributes of the crop. The highest fruit weight, fruit per plant, and fruit yield were observed in treatment with soil test-based NPK recommendation and 125 kg ha-1 of CaSiO3 applied. It was also observed that the relative water content was higher and the water saturation deficit was lower in this treatment. CaSiO3 application @125 kg ha-1 along with soil test-based recommendation of NPK can be recommended as a salt stress mitigation strategy for boosting vegetable production in the salt-affected soils of sandy plains of Kerala.

Sequestration of gene products by decoys enhances precision in the timing of intracellular events

Expressed gene products often interact ubiquitously with binding sites at nucleic acids and macromolecular complexes, known as decoys. The binding of transcription factors (TFs) to decoys can be crucial in controlling the stochastic dynamics of gene expression. Here, we explore the impact of decoys on the timing of intracellular events, as captured by the time taken for the levels of a given TF to reach a critical threshold level, known as the first passage time (FPT). Although nonlinearity introduced by binding makes exact mathematical analysis challenging, employing suitable approximations and reformulating FPT in terms of an alternative variable, we analytically assess the impact of decoys. The stability of the decoy-bound TFs against degradation impacts FPT statistics crucially. Decoys reduce noise in FPT, and stable decoy-bound TFs offer greater timing precision with less expression cost than their unstable counterparts. Interestingly, when both bound and free TFs decay at the same rate, decoy binding does not directly alter FPT noise. We verify these results by performing exact stochastic simulations. These results have important implications for the precise temporal scheduling of events involved in the functioning of biomolecular clocks, development processes, cell-cycle control, and cell-size homeostasis.

Experimental and Numerical Indentation Tests to Study the Crack Growth Properties Caused by Various Indenters Under High Temperature

ABSTRACTThis paper investigates the influence of indenter shape and rock texture on the crack growth properties and rock hardness. For this purpose, two different rock specimens such as basalt and marble with various textures were prepared and tested by Vickers indentation hardness device with rhombus indenter shape under two different temperatures of 35°C and 100°C. Concurrent with the experimental test, Vickers indentation simulations have been done on three calibrated rock models with nine different indenter shapes. The tensile strength of marble was 8 MPa, while basalt had a tensile strength of 10.8 MPa. Regarding compressive strength, marble exhibited 71 MPa, whereas basalt had a compressive strength of 153 MPa. Marble and basalt had elastic moduli of 45 and 95 GPa, respectively. The physical loading was applied vertically at a rate of 0.004 mm/min. The rock's texture and temperature significantly impact Vickers indentation hardness. Penetration by the Vickers indenter creates an elastic‐plastic stress field, leading to radial cracks due to exceeding the critical stress level. Ring cracks are caused by bulging of the test material and nested cracks directly under the indentation due to high shear and bending stresses in the region. The indentation shape affected the extent of the damage zone below it, leading to increased crack growth with smaller indentation diameters. The radial fracture number increased when the cross‐section changed from circular to quadrilateral shape. The crack growth and damage zone area increased with higher rock temperature due to increased rock brittleness.

Fractal Analysis of Mining Wastewater Time Series Parameters: Balkhash Urban Region and Sayak Ore District

The population life and health quality are significantly reduced due to water resources pollution caused by heavy metals, especially in urban agglomerations located close to metal ore mining and processing facilities. The greatest environmental pollution occurs during the extraction of Cu, Zn, and Pb. In this study, a fractal R/S analysis of wastewater discharge indicators time series from a metal ore mining facility located in the Sayak ore district in the Republic of Kazakhstan (turbidity, electrical conductivity, flow magnitude, and pH level) was carried out. A sharp increase in the flow rate was recorded from 10 to 15 July 2024 and an increase in the electrical conductivity from 4 to 26 July 2024. However, the latest type of indicator assessment does not exceed the critical level for life. The presence of electrical conductivity indicators time series long-term memory and persistence was also recorded (the Hurst exponent for the electrical conductivity time series is fixed in the 0.56 to 0.59 range and does not go below the threshold value for randomness according to the Anis-Lloyd formula). Thus, the value-changing process is controlled and stable, and minor changes in turbidity indicate that these releases do not significantly harm the environment. Despite this, the results obtained do not allow for a comprehensive analysis of the state of releases as the data from all deposits is not available. Therefore, due to the time constraints of the data provided for analysis, it is difficult to fully assess the impact of specific metal ore mining facilities on the environmental safety of the Balkhash urban region. In addition, many studies indicate very high risks of chronic diseases for the population living in this region. The findings of this study enable us to conclude that the application of fractal analysis and the calculation of fractal characteristics for time series of emissions can serve as an indicator of the environmental status within the given area. This information can be used by environmental services to build reliable environmental pollution monitoring systems.

Critical levels and fertility classes of soils with high-activity clay in the Brazilian semi-arid region

ABSTRACT Soil fertility evaluation is important for adopting conservation management and adequate nutrient supply. The objective of this study was to identify critical levels and soil fertility classes using the boundary line method for rainfed crops (corn, cowpea and sabiá [Mimosa caesalpiniifolia]) in the Brazilian semi-arid region. A database of 226 soil fertility analyses of samples from the 0.00-0.20 m soil layer, and corn, cowpea and sabiá yields from Ceará State was used to generate interpretation classes (at 80 and 95 % of maximum yield). In a scatter plot, soil nutrient concentrations (x-axis) and relative crop yields (y-axis) were correlated, and the border points fitted to a quadratic model. Proposed interpretation classes were classified as very low, low, adequate, high and very high, except for Na + , whose adequate class was considered tolerable. Generated models showed coefficients of determination (R 2 ) for the chemical properties ranging from 0.54 to 0.92. Based on the interpretation classes, the critical level was determined as 6.3 for pH, 10.8 g dm -3 for OM, 20.9 mg dm -3 for P, 81 mg dm -3 for K, 55 mmol c dm -3 for Ca 2+ , 24 mmol c dm -3 for Mg 2+ and 8 mg dm -3 for S-SO 4 2- . Interpretation classes for soils with high-activity clay in the Brazilian semi-arid region were superior to those in the reference literature. Boundary line method established fertility classes and critical levels for soil chemical properties in more than one crop, using the concept of relative yield.

The Effect of Varying Compaction Levels on Soil Dynamic Properties and the Growth of Canola (Brassica napus L.)

Extremely low field emergence rates for canola are primarily attributed to soil compaction from field traffic during and after planting. This study aimed to determine the critical compaction level for canola emergence across different soil types. A laboratory experiment was conducted using sandy loam, silt clay, and clay soils, compacted to five levels (zero to four) using Proctor hammer drops after sowing canola (Brassica napus L.). The lab results were validated through two years of field experiments in sandy loam, applying four compaction levels (zero to three) using a tractor. Soil properties (bulk density and surface resistance) and canola growth parameters (plant emergence rate, count, height, and above-ground biomass) were measured. Zero compaction resulted in lower bulk density and surface resistance across all soil types. Laboratory results showed maximum emergence rates of 95% for sandy loam, 100% for silt clay, and 60% for clay, while field emergence rates were 63% and 87.59% in the first and second years, respectively, both at zero compaction. Recommendations include light or no compaction for sandy loam, and zero compaction for silt clay, while clay soil did not achieve the 80% emergence target at any compaction level. These results can assist agricultural producers in optimizing their seeding equipment setup and managing field traffic for canola production.

Speaking valve with integrated biomimetic overpressure release and acoustic warning signal

Speaking valves enable tracheostomy patients to speak naturally. However, improper use may cause dangerous overpressure, leading to severe complications or even patient’s death. We address this life-threatening issue by creating a biomimetic speaking valve, which incorporates an integrated overpressure valve that automatically opens when reaching critical pressure levels. To enhance safety, we integrated a whistle module to provide an audible alert for medical staff. Fundamental research on the Utricularia vulgaris trapdoor inspired our abstracted valve form. Through a comprehensive analysis using generalized linear mixed-effect models, we examined various membrane parameter effects on the function of the biomimetic overpressure valve. This enabled us to adjust the valve’s opening pressure to cater to patient’s unique requirements, thus potentially saving lives by applying a solution from nature.

Assessing the impact of the National Clean Air Programme in Uttar Pradesh's non-attainment cities: a prophet model time series analysis

BackgroundUttar Pradesh, India’s largest state, faces critical pollution levels, necessitating urgent action. The National Clean Air Programme (NCAP) targets a 40% reduction in particulate pollution by 2026. This study assesses the NCAP’s impact on 15 non-attainment cities in Uttar Pradesh using the Prophet forecasting model. MethodsMonthly data from 2016 to 2023 on AQI and PM10 concentrations were sourced from the Uttar Pradesh Pollution Control Board. Significant changes in mean AQI and PM10 levels from 2017 to 2023 were evaluated using the Friedman Test. Prophet models forecasted PM10 concentrations for 2025-26, with relative percentage changes calculated and model evaluation metrics assessed. FindingsMost cities exhibited unhealthy air quality. Jhansi had the lowest AQI (72·73) in 2023, classified as 'moderate' by WHO standards. Gorakhpur consistently showed 'poor' AQI levels, peaking at 249·31 in 2019. Western Uttar Pradesh cities such as Ghaziabad, Noida, and Moradabad had significant pollution burdens. Predictions showed Bareilly with over a 70% reduction in PM10 levels, Raebareli 58%, Moradabad 55%, Ghaziabad 48%, Agra around 41%, and Varanasi 40%, meeting NCAP targets. However, Gorakhpur and Prayagraj predicted increases in PM10 levels by 50% and 32%, respectively. Moradabad’s model showed the best performance with an R2 of 0·81, MAE of 17·27 μg/m3, and MAPE of 0·10. InterpretationForecasting PM10 concentrations in Uttar Pradesh's non-attainment cities offers policymakers substantial evidence to enhance current efforts. While existing measures are in place, our findings suggest that intensified provisions may be necessary for cities predicted to fall short of meeting program targets. The Prophet model's forecasts can pinpoint these at-risk areas, allowing for targeted interventions and regional adjustments to strategies. This approach will help promote sustainable development customized to each city's specific needs. FundingNo funding was issued for this research.

Post-transplant G-CSF impedes engraftment of gene-edited human hematopoietic stem cells by exacerbating p53-mediated DNA damage response.

Granulocyte-colony-stimulating factor (G-CSF) is commonly used to accelerate recovery from neutropenia following chemotherapy and autologous transplantation of hematopoietic stem and progenitor cells (HSPCs) for malignant disorders. However, its utility after exvivo gene therapy in human HSPCs remains unexplored. We show that administering G-CSF from day 1 to 14 post-transplant impedes engraftment of CRISPR-Cas9 gene-edited human HSPCs in murine xenograft models. G-CSF affects gene-edited HSPCs through a cell-intrinsic mechanism, causing proliferative stress and amplifying the early p53-mediated DNA damage response triggered by Cas9-mediated DNA double-strand breaks. This underscores a threshold mechanism where p53 activation must reach a critical level to impair cellular function. Transiently inhibiting p53 or delaying the initiation of G-CSF treatment to day 5 post-transplant attenuates its negative impact on gene-edited HSPCs. The potential for increased HSPC toxicity associated with post-transplant G-CSF administration in CRISPR-Cas9 autologous HSPC gene therapy warrants consideration in clinical trials.

Revolutionizing inventory management: A comprehensive automated data-driven model using power BI incorporating industry 4.0

This is a study on advanced inventory management approaches in the mechanical industry using data-driven models, accompanied by Power BI analytics. Drawing insights from broad collaboration with relevant industrial expertise at different organizational scales, our research work addresses the intricacies and challenges in maintaining optimal inventory levels concerning growing industries and operational risks. In this global mechanical firm, we analyzed historical data using descriptive and predictive analytics to understand the trends of the past and to forecast future inventory needs. Descriptive analytics provided base insights about the present status of inventory, while predictive analytics helped proactive management of stock levels classified into on-hand and critical level categories for greater efficiency in strategies related to planning at the coordination end with its suppliers and mitigating risks. Core to our methodology will be the implementation of an automated data-driven machine-learning approach that brings minimal intervention from humans to solve some of the most critical problems in inventory management. One major contribution this study adds is a major product: a Power BI dashboard that visualizes critical part numbers falling below threshold values and recognizes suppliers with historical shipment shortages. Armed with this intuitive dashboard, supplier-coordinating engineers are better placed to take proactive action on inventory shortages, greatly improving operational efficiency in supply chain resilience.

A comprehensive assessment of gold leaching wastewater through pollution and water quality indices. Case study: Small scale extraction facilities in the department of Caldas—Colombia

This study introduced a comprehensive methodology (the Six-Indices method for Water Pollution Assessment) to evaluate the quality of gold leaching effluents. Sampling was conducted for 14 months in small-scale gold mining facilities in the department of Caldas, Colombia. 23 physicochemical parameters were selected based on environmental regulations, standards of use for agricultural purposes and WHO recommendations. They covered general characteristics of effluents and critical inputs of the leaching process. 15 (pH, COD, TSS, CN−, Cl−, SO42−, S2−, Cd, Zn, Cu, Cr, Fe, Ni, Ag, and Pb) of them exceeded permissible limits. Multivariate statistical analysis (Person's correlation and hierarchical clustering analysis) and six Wastewater Quality Indices (WWQIs: Arithmetic Weighted Water Quality Index, WAWQI, Synthetic Pollution Index, SPI, Index of Water Pollution, WPI, Comprehensive Pollution Index, CPI, Heavy Metal Pollution Index, HPI, and Degree of Pollution, Cd) were used to comprehensively assess the effluent contamination. Key pollutant interactions (hydrocarbons & fats and oils, Zn & CN−, Cu & Cl−, as well as CN− & COD & SO42−) were revealed guiding targeted mitigation strategies. CN− and heavy metals were the main pollutants, posing serious environmental risks due to their high levels. The calculated HPI value was above the critical level of 100, indicating that the artisanal gold leaching operations in the studied area could be hazardous to human health. This study provides a starting point for developing effective and sustainable strategies to manage wastewater in mining regions in Colombia and other areas with similar mining practices.

Epidemiological, clinical, paraclinical, evolutionary, and therapeutic aspects of hypertensive patients infected by COVID-19: about 702 patients in our city

Abstract Introduction Hypertension (HT) is a major cardiovascular risk factor frequently observed in COVID-19 patients. This study aimed to determine the frequency of hypertensive patients infected with COVID-19 at a national hospital, describe their epidemiological, clinical, paraclinical, and therapeutic profile, their disease progression, and identify factors associated with death. Methodology A retrospective, descriptive, and analytical study was conducted over 24 months and 4 days, from 27 March 2020 to 30 March 2022, at national hospital. Included were hospitalized patients at a hospital with a confirmed COVID-19 diagnosis, known hypertensives, regardless of gender, and with a hospitalization record. COVID-19 diagnosis was based on a positive SARS-CoV-2 RT-PCR or a positive COVID Rapid Diagnostic Test. Data were collected using a survey form, with a p-value less than 0.05 considered statistically significant for bivariate analysis. Results The study enrolled 702 patients, a hospital frequency of 23.95%. The average age was 65.14 ± 12.24 years with a sex ratio of 0.81. Comorbidities were predominantly diabetes (40.5%) and dyslipidemia (4.8%). Common symptoms included cough (65%), dyspnea (42.3%), fever (47.4%), and asthenia (35.9%). Blood pressure was normal in 15.2%, high-normal in 16.8% of patients. HT was Grade I in 12.1%, Grade II in 10%, and Grade III in 6.8% of the population, with blood pressure unmeasurable in 0.3% of known hypertensive patients. SARSCOV2 infection was mild in 34.2% and moderate in 42.8% of cases. CT scans showed extensive (31.8%), severe (25.9%), moderate (25.6%), critical (8.5%), and minimal (7.9%) lung damage. Treatment mainly consisted of ACE inhibitors (29%), ACE inhibitors in combination with another antihypertensive (8.4%), and ARBs in combination with an antihypertensive (). The average hospital stay was 12.85 days with a favorable outcome in 81% and a mortality rate of 15.5%. Factors associated with death included not being vaccinated against COVID-19 (HR: 11.70; 95% CI: 1.324-103.519), critical clinical form (HR: 11.70; 95% CI: 1.324-103.519), pulmonary consolidation (HR: 8.87; 95% CI: 7.539-24.207), high creatinine (HR: 4.69; 95% CI: 1.360-16.181), critical CT thoracic level (HR: 2.42; 95% CI: 1.020-5.745), and not taking ARBs (HR: 6.02; 95% CI: 2.812-12.889). Conclusion HT can be associated with COVID-19, impacting the disease's prognosis with significant mortality. Preventing its incidence and morbidity/mortality is crucial.

Exploration on flutter mechanism of a damaged transonic rotor blade using high-fidelity fluid–solid coupling method

Structural damage in turbomachinery is a primary origin of aeronautic accidents, which is receiving increased attention. This study is thus focused on the aeroelastic analysis of damaged blades, including the onset of flutter and underlying mechanisms. First, a high-fidelity fluid–solid coupling system is established with computational fluid dynamics (CFD) and computational structural dynamics (CSD) technologies, via which the dynamic aeroelastic analysis is conducted based on static aeroelastic deformation. Second, a damaged rotor blade is parametrically modelled with variable damage levels, extents, and positions. Finally, the modal identification method of spectral proper orthogonal decomposition (SPOD) is applied to observe flow details and provide physical insight into the flutter mechanism for damaged blades. Numerical analysis finds that there is a critical damage level below which the aeroelastic stability is positively improved with increasing damage level; otherwise, a significant loss of stability is induced. The damage location and extent further affect this critical damage level and the change rate crossing the threshold. The simulation with CFD/CSD finds that the high pressure near the trailing edge induced from boundary layer separation suppresses vibrations in stable conditions, but motivates vibrations during flutter, which is because of the high-pressure spread to nearing blades. SPOD modes reveal that high-frequency disturbances with large scale are primary factors inducing flutter, which is further stimulated by the high-order disturbances with small scale. This study provides a crucial foundation for the fatigue prediction for rotor blades in service and the optimisation design for high-performance turbomachinery in the near future.

Irrigation suitability assessment of urban wastewater for sustainable agriculture: a case study of Musi river, India

In urban areas with dense populations and high water demands, effective management of water resources is crucial for sustainable development. It includes optimizing water usage and recycling wastewater to balance supply and demand. Urban rivers, which now carry sewage year-round due to increased urban water consumption, are increasingly used for irrigation in peri-urban regions. This study aims to assess the suitability of an urban stream for irrigation compared to catchment groundwater, using hydrochemical parameters to evaluate water quality indices. Analysis of major ion distribution from upstream to downstream reveals a significant increase of TDS (r2 = 0.65; p < 0.001) in the surface water and a decrease (r2 = 0.93; p < 0.001) in groundwater samples. The calculated Weighted Arithmetic-Water Quality Index (WA-WQI) indicates that around 85% and 75% of surface water and groundwater samples from the Musi river are classified as very poor to unsuitable for any use, highlighting critical pollution levels. Based on irrigation suitability indices, only 16% of the surface water samples and 60% of the groundwater samples are suitable for irrigation. The nitrate concentration increased from less than 10 mg l−1 in the upstream region to over 100 mg l−1 in the urban stretch. Nitrogen-Phosphate-Potassium (NPK) ratios across the basin are exceptionally higher, representing crops irrigated using the Musi river water might not require fertilizer applications. The adoption of fertilizer application concerning supplied water hydrochemistry, particularly the NPK ratio, might limit the excess usage of fertilizer and benefit farmers. Additionally, this practice may also limits the excess input of nitrate to the groundwater in the Musi river basin.