Allowable Limits Research Articles

Comparison of HPLC with Tinia for hba1c measurement in diabetic and non-diabetic patient; a study from a tertiary care hospital of Baluchistan

Background: Diabetes mellitus, a disease with serious implications on human health ,is on continuous rise. It is the need of hour to find and establish the markers to measure its long term effects. Diabetes Control and Complication Trial has confirmed role of HbA1c in effective blood glucose level monitoring .New methods are being developed for measurement of HbA1c .Before using these methods, it is essential to analyze these methods for reliability .Therefore in our study we will compare and evaluate correlation and agreement between Turbidimetric Inhibition Immunoassay TINIA and High Performance Liquid Chromatography HPLC for HbA1c measurement. Methods: Three hundred and ninety-four samples were analyzed simultaneously on Roche Cobas 501 and D-10 HbA1c analyzer by Bio-Rad for HbA1c level estimation. The results were entered into SPSS version 26 for method validation. This is an observational study conducted at Department of Pathology CMH Quetta from January 2022 to August 2023. Results: Inter and intra run coefficient of variation (CV) was within the allowable limit of 2 %. Mean difference between results of Turbidimetric Inhibition Immunoassay TINIA and High-Performance Liquid Chromatography HPLC was very low with HPLC results slightly on higher side. For low control TINIA had between run CV of 0.3% (Low control) 0.8 % (High control) and within run CV of 0.3% (Low control), 0.6% (High control); while HPLC had between run CV of 0.6%(Low control) 1.8% (High control), and within run CV of 0.3% (Low control), and 0.7%. Linear regression analysis displayed high concordance and agreement between the results of both methods. Conclusion: Both methods have comparable results in HbA1c estimation.

Assessing the impact of human activities on the health condition of the Lukosi River catchment using selected physico-chemical parameters as indicators of water quality

The Lukosi River catchment plays a crucial role in the economic and ecological framework of the country, serving as a major contributor to the Great Ruaha River (GRR). This study aimed to assess the impact of human activities on the health of the Lukosi River by analyzing key water parameters. Three sampling sites across the catchment were selected, and water samples were collected and analyzed using the American Public Health Association technique. A one-sample t-test was used to measure the significance of the difference between the measured water quality parameters and the water quality criteria established by the Tanzania Bureau of Standards (TBS) and the World Health Organization (WHO). The results revealed mean values for various parameters: pH (8.67 ± 0.57), temperature (24.803 ± 1.361°C), EC (93.30 ± 3.34 mgL−1), BOD (14.85 ± 1.49 mgL−1), TDS (46.95 ± 1.55 mgL−1), total hardness (27.53 ± 1.28 mgL−1), DO (3.4 ± 0.53 mgL−1), turbidity (109.83 ± 40.99 mgL−1), NO2 (79.04 ± 0.73 mgL−1), Cu (6.07 ± 0.60 mgL−1), Ca (7.88 ± 0.36 mgL−1), Mn (0.16 ± 0.07 mgL−1), Cl (7.58 ± 3.97 mgL−1), F (0.12 ± 0.0008 mgL−1), SO4 (20.42 ± 4.12 mgL−1), Mg (1.92 ± 0.13 mgL−1), Zn (0.14 ± 0.11 mgL−1), Fe (3.56 ± 0.15 mgL−1), and NH3 (4.67 ± 0.51 mgL−1). Parameters such as DO, turbidity, NH3, NO3, and BOD significantly (p = 0.05) exceeded the permissible limits set by the TBS and the WHO. Furthermore, elements including Fe and Cu exceeded allowable limits. Moreover, the WQI was used to indicate that the water in the catchment is unsuitable for sustaining aquatic organisms and is unfit for domestic use. Household questionnaires and direct observations identified key human activities in the catchment: gardening (78.3%), agriculture (68%), livestock keeping (50%), sand mining (21%), and brick-making (21%). Less prevalent were car washing (7%) and fishing (4%). These findings underscore the urgent need for conservation efforts and sustainable management practices to safeguard the Lukosi River catchment (LRC).

Prospective and External Validation of an Ensemble Learning Approach to Sensitively Detect Intravenous Fluid Contamination in Basic Metabolic Panels.

Intravenous (IV) fluid contamination within clinical specimens causes an operational burden on the laboratory when detected, and potential patient harm when undetected. Even mild contamination is often sufficient to meaningfully alter results across multiple analytes. A recently reported unsupervised learning approach was more sensitive than routine workflows, but still lacked sensitivity to mild but significant contamination. Here, we leverage ensemble learning to more sensitively detect contaminated results using an approach which is explainable and generalizable across institutions. An ensemble-based machine learning pipeline of general and fluid-specific models was trained on real-world and simulated contamination and internally and externally validated. Benchmarks for performance assessment were derived from in silico simulations, in vitro experiments, and expert review. Fluid-specific regression models estimated contamination severity. SHapley Additive exPlanation (SHAP) values were calculated to explain specimen-level predictions, and algorithmic fairness was evaluated by comparing flag rates across demographic and clinical subgroups. The sensitivities, specificities, and Matthews correlation coefficients were 0.858, 0.993, and 0.747 for the internal validation set, and 1.00, 0.980, and 0.387 for the external set. SHAP values provided plausible explanations for dextrose- and ketoacidosis-related hyperglycemia. Flag rates from the pipeline were higher than the current workflow, with improved detection of contamination events expected to exceed allowable limits for measurement error and reference change values. An accurate, generalizable, and explainable ensemble-based machine learning pipeline was developed and validated for sensitively detecting IV fluid contamination. Implementing this pipeline would help identify errors that are poorly detected by current clinical workflows and a previously described unsupervised machine learning-based method.

Optimized Cultivation of Stropharia rugosoannulata Using Winter Jujube Wastes and Safety Risk Assessment of the Cultivated Mushrooms

Substantial agricultural waste, including winter jujube residues, pits, and sawdust, is generated during the planting and processing of winter jujubes. To recycle these wastes, they were used to cultivate Stropharia rugosoannulata. The nutrient composition, mineral elements, 179 pesticide residues, and heavy metals in the wastes and S. rugosoannulata were tested. Cultivating the liquid spawn of S. rugosoannulata with 40 g/L winter jujube residue as a substitute for glucose significantly increased the mycelial pellets’ biomass by 136%, resulting in more uniform pellets. Secondary strains of S. rugosoannulata were cultured using winter jujube pits, showing no significant difference in mycelial growth rate and vigor compared to the control (CK) across additive levels of 10%–30%. The fruit bodies of S. rugosoannulata cultivated with winter jujube sawdust exhibited no detectable pesticide residues and a lower heavy metal content than the allowable limits, with a protein content of 36.7 g/100 g. Additionally, the mineral element potassium surpassed sodium by over 200 times, rendering it a potassium-rich, low-sodium food source. Utilizing winter jujube wastes for S. rugosoannulata cultivation effectively repurposed these wastes through sustainable recycling. This approach not only reduces cultivation costs but also yields safe and nutritious edible fungal products.

Investigation of the Durability of the Regulating Junction of the Christmas Tree Throttle

Objective: In the research work, the issue of ensuring the stability of its details wasconsidered by studying the voltage distribution mode in the throttle control node. SolidWorks software was used to perform force analysis of the improved throttle. Theoretical Framework: The research draws upon theories and simulations related to regulatory constructions and wear prevention. Methodology: In the research work, the performance criteria of the improved throttle have been studied. The force analysis of the proposed throttle's regulating node was carried out using modern methods and Solidworks simulations. Results and Discussion: The analysis of the wear occurring at the tip of the improved throttle shows that the wear resistance of this equipment is ensured, and the wear of the saddle-cutter pair, which has a hardness of HRC=55-66, amounts to 0.040...0.050 mm after 500 forward-backward cycles intended for the throttle. This is also twice smaller than the allowable limit. The processing of the conducted force analyses has proven that the performance of the improved throttle is ensured. Research Implications: The structural force analysis of the improved throttle shows that its performance is ensured. An analytical expression has been obtained to determine the maximum value of the radial stresses occurring at the tip of the throttle. It has been found that the safety factor for bending stress in the central zone of the throttle tip is equal to 2.5. Originality/Value: Based on simulations and analytical calculations, the radial stresses generated at the tip of the nozzle were investigated, and the longevity of the improved nozzle was enhanced based on new approaches.

Dynamic Wireless Sensor Network-Based Structural Health Monitoring System for Retractable Roof Structure

Retractable roof structure (RRS) works optimally under varying weather, but is prone to damage due to its complexity, requiring monitoring. Given RRS's large scale, wireless sensor networks (WSNs) are preferred, with dynamic WSNs better adapted to its motion than static ones. A tree-type network topology was designed for dynamic WSN, enabling fast self-routing. It is divided into subnets, each with a relay node as the parent and subordinate relay and sensor nodes as children. Network address reassignment method was proposed to sustain WSN communication during motion. This method involves operations of subnet affiliation change and relay node replacement, the former adjusts the hierarchy between relay nodes across different subnets while preserving parent-child relation within each subnet, and the latter swaps the roles of relay and sensor nodes within one subnet to form a new subnet. Basic communication module with processing, communication, and power management units was used to connect nodes. Dynamic WSN-based structural health monitoring (SHM) system with 372 sensors was developed for the Textile City Sports Centre Gymnasium. Mean errors between simulated and measured results were 10.4% for displacement, 13.6% for stress during construction, and 13.3% for tension during service, indicating good agreement. This suggests that the SHM system operated well in both phases. Maximal stress and displacement after unloading were 215.9 MPa and 549 mm, below allowable limits. Monitoring results revealed temperature field non-uniformity with a 9°C maximal difference, and strong temperature-stress correlation, with Pearson coefficients of 0.971, 0.973, and 0.955 for tie rod, chord, and web. RRS movement significantly impacted midspan tie rods in long main trusses, with a mean tension change exceeding 1000 kN. The research methods and conclusions offer valuable references for developing and applying RRS's SHM system.

Case study of bearing capacity failure in a 4-story reinforced concrete building

This case history analyzes the bearing capacity failure of a 4-story reinforced concrete building in Benghazi, Libya, constructed in Fall 2000. The building has a plan area of 65 m² and is supported by an 80 cm thick raft foundation resting on collapsible sandy loess, which can lose shear strength when wet. Several months before the building's failure, nearby construction work caused a broken pipeline, leading to significant water leakage. This moisture infiltrated the soil under the foundation, reducing its bearing capacity, particularly on the northern side. In winter 2002, the building began to tilt northward due to this reduced capacity, although inspections revealed no structural cracks, attributed to the rigidity of the raft foundation and reinforced concrete shear walls. The paper discusses the geotechnical properties of the supporting soil and uses finite element analysis to show that the bearing pressures exceeded allowable limits under wet conditions, emphasizing the importance of moisture content in assessing soil stability. This case highlights the complexities of foundation design and the critical impact of environmental factors on soil behavior, advocating for thorough geotechnical assessments and ongoing monitoring of conditions around structural foundations.

Modeling Cs-137 Migration in Groundwater due to Low Probability Event of Leaching from Near Surface Disposal Facility for Low Level Solid Radioactive Waste

In this paper, we present impact of Cesium-137 (Cs-137) disposal in a Near Surface Disposal Facility (NSDF) with respect to groundwater migration and its consumption for drinking. We employ the Multiple Area Source Model for simulating the fate of radionuclide in groundwater to evaluate its potential contamination due to extremely low probability event of leaching from the NSDF. The assessment conservatively assumes direct interaction between disposal trenches and the underlying aquifer neglecting the barrier provided by the unsaturated zone. Temporal profiles of concentration of Cs-137 at different down flow distances in groundwater are obtained over a period extending several years post-disposal. The results indicate that even under such a worst-case conservative scenario and for an annual disposal rate of 3 TBq/y for a period of 50y, the maximum Cs-137 concentration in groundwater remains significantly below the safe drinking water threshold of 10 Bq/L recommended by the World Health Organization. It is found that amount of Cs-137 generally disposed in NSDF is significantly lower than the allowable disposal limit corresponding to concentration defined for safe drinking water limit.

Laser beam welding of T joints for aluminum–Copper–lithium aircraft panels: Effect of filler wire on recyclability and weldability

This study assessed the weldability and recyclability of four filler wires, two commercial (ER4047 and ER2319) and two experimental (ER2395 and J300), for laser beam welding of aluminum-Copper-lithium (Al–Cu–Li) aircraft panels. The results showed key differences in porosity and crack formation. The ER2319 filler exhibited a higher tendency for wormhole-type porosity compared to the others, which had similar pore area fractions. ER2395 displayed the longest crack length, likely due to its high lithium content. Chemical compatibility with the Al–Cu–Li base alloy AA2198 was confirmed for the ER2319, ER2395, and J300 filler wires, enabling 100% closed-loop recyclability without disassembly or alloy sorting. However, the high silicon content (around 11%) of ER4047 resulted in a recycled alloy that exceeded the allowable Si limit for AA2198, making it unsuitable for closed-loop recycling. Several end-of-life (EoL) strategies were explored for scrap fractions from ER4047-welded coupons. The 0C and 1C cutting strategies yielded hybrid fractions incompatible with AA2198 but suitable for the more Si-tolerant AA2196 alloy. The 3C strategy, involving weld seam separation before remelting, optimized recycling rates and minimized environmental impact. Additionally, a pre-scrap characterization method was developed to analyze weld seam composition, allowing for the prediction of recyclability issues and filler wire mass estimation in coupons where both the skin and stringer were made of the same alloy. This method provides a practical approach for evaluating welded structures in future recycling efforts.

Comparative analysis of the physicochemical properties and trace metal content of palm oil, from selected markets in Jos south and Jos north LGA, Plateau state, Nigeria

The quality of palm oil samples collected from three different markets in Jos South and Jos North Local Government Area of Plateau State were analyzed and evaluated using standard analytical laboratory procedures. The relative ranges of the physicochemical values obtained were as follows; Moisture Content (MC): 0.56 - 1.89, Iodine value (IV); 51.88 - 55.57 g I2/100g, Peroxide Value (PV): 0.98 - 4.16 mEq02/kg, Saponification Values (SV): 198.46 - 201.54 mgKOH/g, Acid Value (AV): 9.93 - 57.65, and Refractive Index (RI), 1.4576 - 1.4580. The moisture content, iodin value, pH values and acid values were found to exceed the Standard Organization of Nigeria (SON) permissible limits of moisture content (0.29 mgKOH/g), iodine value (45 - 53 mg I2/100g), pH (5 - 7 mg/L), and acid value (0.7 max mg/L) for edible oils respectively while the refractive index, saponification values, peroxide values falls within the SON allowable limits of refractive index (1.4612-1.4707 mg/L), saponification value (195-205 mgKOH/g) and peroxide value (10 mEq02/kg) respectively . The amounts of trace metals (Cu, Zn, Fe, Pb and Cd) determined in the palm oil using the atomic absorption spectrophotometer ranged from Cu(0.34 - 0.52 mg/l), Zn(1.58 - 2.33 mg/l), Fe(19.18 - 26.74 mg/l), Pb(2.87 - 4.06 mg/l) and Cd(1.58 - 2.24 mg/l). However, the levels of Zn, Fe, Pb and Cd exceeded the WHO/FAO recommended values of (1.50, 1.00, 0.05 and 0.02 mg/L) respectively while only Cu concentration was below the WHO/FAO limits of 2.00 mg/L for trace metals in edible palm oil. Consequently, the results of this study shows that the palm oil consumed from these selected markets does not meet the standard quality specification for edible palm oils and hence can post significant health threat to consumers. Therefore, food regulatory agencies should strengthen their surveillance to promote food and health safety of the populace.

Impact of Shelf life on the Quality of Cocoa Butter Extracted by Screw Press

Aims: To evaluate the changes in the quality of cocoa butter during storage extracted using the developed screw press-type cocoa butter extractor. Study Design: Statistical analysis was done using t-test. Place and Duration of Study: The study was conducted at Processing and Food Engineering lab, Kelappaji College of Agricultural Engineering and Food Technology, Tavanur under ICAR-AICRP on Post-Harvest Engineering and Technology Scheme for 3 months. Methodology: Shelf life study of the cocoa butter extracted at optimized condition (100ºC barrel temperature, 50 rpm screw speed, 2 kg/hr feed rate) was done in polyethylene pouch of 80 micron thickness and stored under ambient temperature (25±5°C) for a period of 3 months. Various quality parameters viz., free fatty acid, iodine number, peroxide number, moisture content and water activity of stored butter were determined at regular intervals of 30 days for 3 months. Results: Statistical analysis (t-test) showed that, there was no significant changes in the quality of cocoa butter during storage. The quality parameters of cocoa butter viz.,free fatty acid (1.28%), iodine number (34.74), peroxide value (1.685), moisture content (0.15%) and water activity (0.645) were within the allowable limits recommended by CODEX standards even after 3 months of storage. Conclusion: During the course of storage, all quality parameters viz., free fatty acid, peroxide value, iodine number, moisture content and water activity were found to be increased. However, all the quality parameters of cocoa butter stored under ambient temperature were within the acceptable limit prescribed by CODEX standards till 90 days with constant quality attributes.

A comparative study of DPPH radical scavenging property and antiproliferative potential on human hepatic cancer (HepG2) cells of methanolic extracts from different parts of <i>Ludwigia hyssopifolia</i> and <i>Ludwigia adscendens</i>

Ludwigia hyssopifolia and Ludwigia adscendens are two indigenous and common plant species in Vietnam with hepatoprotective property mentioned in numerous articles published in international journals. Therefore, the current paper aimed to evaluate the physicochemical parameters, total polyphenolic and flavonoid contents of the methanolic extracts from 04 parts of Ludwigia hyssopifolia and Ludwigia adscendens in Mekong delta, Vietnam. Most importantly, antioxidant properties by DPPH radial scavenging assay and antiproliferative potentials on human hepatic cancer (HepG2) cells of these multiple extracts also were determined in the in vitro models. These results showed that physicochemical parameters were within allowable limits according to the literatures. Among the investigated samples, the leaf and whole plant extract from Ludwigia hyssopifolia had the highest values of total phenolic and flavonoid contents being 196.55 ± 5.05 mg GAE/g and 64.72 ± 4.63 mg QE/g respectively. Additionally, the methanol whole plant extract of Ludwigia hyssopifolia and the methanol leaf extract of Ludwigia adscendens show the greatest antioxidant properties in DPPH scavenging assay with IC50 values of 44.48 ± 4.29 µg/mL and 26.11 ± 0.37 µg/mL respectively. Furthermore, the methanolic extract from Ludwigia hyssopifolia leaves displays the most potential anti-HepG2 activity among all surveyed samples. Therefore, the most promising extracts need further evaluation for potential herbal product developments.

ASSESSMENT OF THE LEVELS OF NATURAL RADIOACTIVITY AND THE POSSIBILITY OF RADIATION RISKS IN SOIL SAMPLES TAKEN FROM DIFFERENT LOCATIONS IN SOUTHERN ALMAZAR-ALKARAK, JORDAN

A wide study of environmental radioactivity levels in soil samples from Southern Almazar-Alkarak in Jordan was performed to develop a radiological map of the area. 15 soil samples were collected from different locations across the region and subjected to analysis using a high-purity germanium detector (HPGe). The study showed that the average levels of natural radionuclides 226Ra, 232Th, 238U and 40K were 34.5±0.98, 25.6±1.3, 32.2±3.7 and 278.5±15.7 Bq.kg−1, respectively. Also, to evaluate the radiological danger, the radium equivalent activity (Raeq) is calculated, absorbed gamma dose rate (D), annual effective dose equivalent (AEDE) and external hazard index (Hex), internal hazard index (Hin). The average values for these parameters were determined to be 92.5 Bq.kg−1, 43.0 nGy h−1, 52.7 µSv y−1 and 0.25Bq.kg−1, 0.34Bq.kg−1 respectively. The values of the gathered samples stay below the allowable limits. Consequently, the examined region does not present any radiation risk to the general population. Moreover, it has been discovered that there is no concentration of 137Cs radionuclide activity in the studied area.

Analysis of the degradation in transmission accuracy of RV reducers considering the wear clearance between cycloidal wheels and pinwheels

To accurately determine the transmission accuracy degradation pattern of Rotate Vector (RV) reducers due to wear, a predictive method is proposed that simultaneously considers the initial clearance and wear clearance between the cycloid wheel and the pinwheel. The initial clearance is derived from a comprehensive gear system analysis, considering assembly errors, manufacturing errors and modifications. Building on this, the wear depth of the cycloid wheel tooth profile is numerically simulated using Archard's wear theory, revealing the wear distribution pattern under various operating conditions. A Gaussian regression model is used to predict the maximum wear amount for different operational durations. Based on the predicted wear amount, a multi-body dynamic simulation model incorporating wear clearance was established to analyze the transmission error under varying clearance conditions. Results indicate that the wear depth along the tooth profile initially increases and then decreases. The depth and region of wear along the tooth profile gradually increase with load and output speed, with the impact of load on the wear region being greater than that of output speed. Under the initial clearance condition, the maximum transmission error is 22.91″. As the wear clearance increases, transmission accuracy declines sharply. When the cumulative wear clearance reaches 0.2 mm, the transmission error exceeds the allowable backlash limit. This study provides a theoretical reference for predicting accuracy degradation and guides the manufacturing design of RV reducers.

Enhancing agricultural sustainability through optimization of the slaughterhouse sludge compost for elimination of parasites and coliforms

For a sustainable ecology, slaughterhouse sludge must be managed effectively in preview of the parasitic or coliforms’ spill over to the community. In order to determine the effectiveness of a customized biological decomposer solution in lowering the parasitic eggs and coliform bacteria, three composting units (Unit 1, Unit 2, and Unit 3) were treated with its different amounts. Over a period of 60 days, pH, temperature, humidity, number of the parasitic eggs per gram (EPG) of faecal material, viability of eggs, and coliform counts were evaluated. By the fifth day of the composting process, pH had significantly (P < 0.05) increased across all the treatments and then decreased gradually. Also on the 5th day, all three units entered the thermophilic range (> 45 °C), which persisted for 20 days for Unit 3 and 15 days for Units 1 and 2. Humidity levels initially increased significantly (P < 0.05) in all three units (Unit 3 = 71%, Unit 2 = 64%, and Unit 1 = 55%) but then gradually decreased. On day 5, no decrease in EPG in Unit 1 was detected; however, a non-significant (P > 0.05) 12.5% decline in EPG in Unit 2 and Unit 3 was recorded. After that, a significant (P < 0.05) reduction in EPG was observed in all the three treatments until day 25. By day 5, decreased egg viability was significantly (P < 0.05) recorded in Unit 3 (21.43%); in Unit 1 and Unit 2, the decrease was 6.25% and 14.29%, respectively. Additionally, all units showed a significant (P < 0.05) decrease in total coliforms, meeting minimum allowable limit in Unit 2 and 3 on day 10 and on day 15 in Unit 1. The most substantial reduction in faecal coliforms was observed in Unit 3 (from 2.6 log₁₀ to 1.3 log₁₀), followed by Unit 2 (from 2.6 log₁₀ to 1.5 log₁₀), and then Unit 1 (from 2.6 log₁₀ to 1.6 log₁₀). The results of this study support recommendation of advanced composting techniques to eradicate or reduce the abundance of pathogens (parasites and coliforms). Hence, we endorse the value of careful composting procedures in environment-friendly abattoir waste management and agricultural practices through creating pathogen-free, eco-friendly fertilizers to promote both agricultural and environmental sustainability.

Evaluations of Groundwater Quality using Principal Component Analysis and Associated Multivariate Techniques: A Case History in Ewekoro Communities, South-West Nigeria

The quest for quality water consumption is comprised of integration of numerous techniques from different professionals whose contributions go a long way in determining overall health status and wellness of any given society. The water quality status of boreholes in Ewekoro communities of Ewekoro Local Government Area, South-West Nigeria was investigated in this work. Water samples were collected from 25 boreholes at various sampling stations across the study area. Standard analytical water quality methods using Inductively Coupled Mass Spectrometry (ICP-MS)/Optical Emission Spectrometry (ICP-OES) and Pour Plate Techniques were respectively employed in the laboratory for the samples’ geochemical and bacteriological analyses. The raw data were processed and analyzed using Principal Component Analysis and other multivariate techniques with Excel and SPSS 20.0 statistical software packages with the corresponding outcomes systematically compared with water quality standards. For the PCA, the varimax rotation converged in 23 iterations with 6 components extracted which accounted for 92.76% of the total cumulative variance respectively observed for geochemical parameters. Na2+, K+, Ca2+, Cl-, SO42-, NH4+, PO43-, and HCO3-, Mg3+, Cu2+, Cd2+, Zn2+, Ni, S , Si, Fe3+, NO3− and Al3+ played a significant contribution with higher factor loading supported by the dominance of HCO3− among the water quality determinants. The rotation converged in 8 iterations with 3 extracted components that accounted for a total cumulative variance of 90.99% % with pH, TEMP, EC, BOD, TS, TURB, ALK, TH, TDS, THC, and DO in the Physico-chemical Parameters series. Most quality determinants in the sampled water are within allowable limits of the approved water quality standards including WHO except Alkalinity, HCO3−, MgCO3−, Cl−, BOD, Cd2+, Fe3+ and Zn2+. The overall ionic dominance pattern follows the same trend K+ &gt;Na2+ &gt; Fe3+ &gt;Mn2+ and Cl- &gt;NO3- &gt;NO2-. The results of the microbial analyses revealed the highest Total Coliform Count of 17 x 102 MPN/100 ml while that of THBC and FCC were reported as 7.8 ×102 cfu/ml and 1.2×102 cfu/ml respectively. The hygienic status of the water sources was found to be poor. High BOD, Coliform Count and BOD5:NO3- ratios of 248.23 recorded for the groundwater samples were suggestive of possible organic pollution due to faecal invasion with the lowest measured depth of 35m. Multivariate statistical approaches namely Correlation, Principal Component Analysis and Descriptive statistics simplified and identified the interrelationship among the analyzed physicochemical parameters and the pollution sources. This study has therefore revealed that boreholes in Ewekoro were polluted and posed potential risk to biomedical safety and overall human health. Intervention measures are therefore necessary to safeguard the inhabitants from water-related diseases and their consequences.

Appraisal of contamination, hydrogeochemistry, and Monte Carlo simulation of health risks of groundwater in a lithium-rich ore area.

This study incorporated hydrogeochemical facies, the entropy-weighted water quality index (EWQI), multivariate statistics, and probabilistic human exposure assessment to investigate hydrogeochemistry, analyze groundwater quality, and estimate potential risks to human health in a lithium-rich ore area (Jadar River basin, Serbia). The findings designated the Ca·Mg-HCO3 hydrogeochemical type as the predominant type of groundwater, in which rock weathering and evaporation control the major ion chemistry. Due to the weathering of a lithium-rich mineral (Jadarite), the lithium content in the groundwater was very high, up to 567mg/L, with a median value of 4.3mg/L. According to the calculated EWQI, 86.4% of the samples belong to poor and extremely poor quality water for drinking. Geospatial mapping of the studied area uncovered several hotspots of severely contaminated groundwater. The risk assessment results show that groundwater contaminants pose significant non-carcinogenic and carcinogenic human health risks to residents, with most samples exceeding the allowable limits for the hazard index (HI) and the incremental lifetime cancer risk (ILCR). The ingestion exposure pathway has been identified as a critical contaminant route. Monte Carlo risk simulation made apparent that the likelihood of developing cancerous diseases is very high for both age groups. Sensitivity analysis highlighted ingestion rate and human body weight as the two most influential exposure factors on the variability of health risk assessment outcomes.

Influence of Joint Stiffness on Three-dimensional Deformation Mechanisms of Pipelines under Tunnel Active Face Instability

Although extensive research has been conducted in literature to investigate tunnelling effects on pipelines, the performance of existing jointed pipelines subjected to excessive tunnel movement has not been investigated. This study sets out to examine the effects of tunnel active instability on three-dimensional deformation patterns of existing pipelines using physical model tests. Tunnelling induced ground / pipeline settlement, joint rotation, and bending strain under various horizontal tunnel face movements are systematically explored. Results show that the tunnel face pressure at the active limit state is practically independent of tunnel cover to diameter ratio (C/D). Existing pipelines that fall within a range of 0.1 D ~ 0.5 D ahead of the tunnel face experience excessive settlements, significant bending strains and joint rotation. The measured peak settlement of pipelines at 0.3 D in front of the tunnel face exceeds the allowable limit, and the maximum settlements in the jointed pipeline are up to 2.67 times those observed in the continuous pipeline. Meanwhile, the joint rotation angle and settlement induced in the jointed pipeline are greatly affected by the C/D ratio and decrease by up to 55.5% and 22.0% with an increasing C/D ratio from 1.0 to 1.5.

Design of Two-Layer Roller Compacted Concrete with Joints by KENSLAB

Roller compacted concrete (RCC) is a type of rigid pavement that is designed in a similar way to conventional concrete pavements reflecting its mode of failure. The thickness design of RCC pavements is based on keeping the flexural stresses and fatigue damage in the pavement caused by wheel loads within allowable limits. As in all jointed concrete pavements, there is a greater effect from loads placed along edges and less at interior locations in the pavement. Joints in RCC pavement are clearly critical areas and form weak points. RCC is typically constructed with saw-cut joints to prevent random cracking, improve the appearance of the pavement surface, and maintain the highest possible load transfer across the joints. This paper presents an approach to designing the thickness of a two-layer RCC with induced cracks (i.e., joints) based on load transfer stiffness and fatigue damage, using the KENSLAB program to obtain pavement life, predict joint deterioration, and pavement damage.

A Groundwater Quality Index Proposed for Assessment of Groundwater Quality: A Case Study of Quang Tri Province, Central Vietnam

Background: Water quality assessment is a crucial task to manage water sources and control water pollution. The purpose of this study is to develop a Groundwater Quality Index (GWQI) to assess groundwater quality. Methods: The GWQI was developed and functioned by weight (wi) and sub-index (qi) of ten selected water quality parameters. Principal Component Analysis (PCA) was applied to a water quality monitoring data set (year 2016 to 2019, 163 samples) at 27 locations in Quang Tri province, aiming to identify the weight of each parameter. Sub-index linear function was established based on the allowable limits for each parameter defined in the National Technical Regulation on drinking water quality. Multiplicate (GWQIM), additive (GWQIA), and reference (GWQIRef) formulas were used to compute the final GWQI indices. The sensitivity and suitability of the proposed GWQI in water quality evaluation were also tested. Results: Among the three GWQI calculation methods, GWQIM was found to be the most suitable in reflecting groundwater quality in the study area. From 2019 to 2022 (152 samples), in the province, 63.2% of GWQIM values were classified as EXCELLENT or GOOD, 17.1% as POOR, and 19.7% as VERY POOR, or UNFIT FOR DRINKING. Conclusion: This improved GWQI can be applied to assess groundwater quality at local or regional scales.