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The relationship between the soil water characteristic curve (SWCC) and the mechanical behavior of unsaturated soil is imperative and has been well investigated. However, the correlation between elastic wave velocity along the wetting and drying paths of SWCC is largely unknown due to the nonavailability of a standard experimental setup for such a purpose. An ordinary triaxial apparatus has been modified for laboratory assessment of SWCCs under different Ko stresses, along with the measurement of shear and compression wave velocities in due course. The main aim of the study is to draw SWCC, wave velocity characteristic curve (WVCC), and a Poisson’s ratio characteristic curve (PRCC) and to establish the phenomenon that these curves possess hysteresis. The Poisson’s ratio was obtained indirectly by measuring Vp and Vs. Three soil samples with relative densities of 85%, 56%, and 39% were prepared and placed in a modified triaxial test apparatus under wetting and drying cycles. The test results showed that the newly developed apparatus is accurately capable of measuring SWCC. Owing to the similarity in the shape of wave velocity and Poisson’s ratio, response to SWCC, WVCC, and PRCC are drawn. The phenomenon of stress history and the effective stress of the soil affected the behavior during wetting and drying paths.

There has been a lot of interest in alternative fuels due to the depletion of petroleum supplies and growing environmental concerns. Biodiesel is made from renewable resources and is one of the many practical and beneficial fuel substitutes for fossil fuels. Recent advancements in nanotechnology have made it feasible to use nanoparticles as fuel additives for internal combustion engines. An earlier study suggested that these compounds might enhance engine performance. There has been a concern that this may increase the particulate matter emitted with the exhaust which adversely affects the air quality. The size-distribution of unregulated particulate matter (PM) emitted with exhaust gases is examined in this work. Under various load conditions, PM exhaust emissions were examined while keeping the engine running at a constant 1350 rpm. A nanoparticles of 50 parts per milligram of Aluminum oxide Al2O3 and Iron oxide Fe2O3 into the jatropha biodiesel / diesel fuel blend. When the engine is fueled with blend of diesel, biodiesel, and nanoparticles ternary fuel, it created fewer particulate matter emissions than the diesel/biodiesel binary blend which contains no nanoparticles. In comparison to pure diesel fuel, the diesel/biodiesel blend binary combination produced 10–15 % less PM1, PM2.5, PM7, and PM10 emissions which is very critical to air pollution problem with the fine/very fine particles.

Structures are recommended to be designed and constructed with the integration of structural health monitoring techniques to ensure that they can dissipate a large amount of energy without considerable damage when subjected to earthquakes. Hysteretic (H), friction (F), viscous (V), and viscoelastic (VE) dampers were employed in this study to observe the response of buildings using the commercially available software ETABS. The effect of different dampers along with configurations on three prototype concrete buildings (3, 5, and 10-storey) was studied by performing a time history analysis. Initially, the response of the buildings was observed in terms of storey drifts, base shear, and displacement without using dampers, while gradually increasing the damping ratio from 0 to 40%. Subsequently, the response of the buildings was evaluated in terms of displacements and base shear using various types of dampers with different configurations. The analysis results demonstrated that the effectiveness of viscous and viscoelastic dampers is higher for 3 and 5-storey buildings, while friction and hysteresis dampers are more suitable for 10-storey buildings. This information enables informed decisions regarding the performance and maintenance of dampers, contributing to the overall resilience and durability of structures in seismic events.

This review paper addresses the recent and past advancements in investigating the anisotropic behavior of foliated metamorphic rock strength subjected to uniaxial or triaxial compression loading, direct or indirect tensile loading, and shear loading. The experimental findings published in the literature show that the strength of foliated rocks is significantly affected by varying the angle β between weak planes and major principal stress. A higher value of strength is reported at β = 0° or 90°; whereas a low strength value is noted at intermediate angles between β = 0° and 90°. The strength anisotropy depends on the degree of schistosity or gneissosity, which is the result of the preferred arrangement of phyllosilicate minerals under differential pressures. The failure of foliated rocks starts at the microscopic scale because of the dislocation slip, plastic kinking, and fracturing in phyllosilicate minerals such as mica. Tensile wing cracks at the tip of the mica propagate parallel to the deviatoric stress. Then, intergranular and intragranular shear-tensile cracks coalesce and lead to rock failure. The weak planes’ orientation controls the mode of failure such that tensile splitting, slip failure, and shear failure across foliations are observed at β = 0°–30°, β = 30°–60°, β = 60°–90° respectively. In the past, several attempts have been made to formulate failure criteria to estimate rock strength using different mathematical and empirical approaches. Over the years, the trend has shifted towards discontinuum modeling to simulate rock failure processes and to solve problems from laboratory to upscaled levels.

Diverse sets of critical success factors (CSFs) have been proposed in the literature, emphasising various facets of stakeholder management. Therefore, it is essential to investigate the ranking and groupings of these factors. This paper seeks to uncover CSFs related to stakeholder management in construction projects in Pakistan and explore their ranking and underlying relationship. A literature study revealed the existence of 18 CSFs. A questionnaire comprising these 18 CSFs was distributed to construction professionals in Pakistan, and 89 completed surveys were recouped. “Formulating the project mission”, “Communicating with stakeholders properly and frequently (instituting feedback mechanisms)”, and “Carefully identifying and listing the project stakeholders” were identified as the top three ranking factors for stakeholder management. Utilizing factor analysis and considering the significance of the factor “Formulating the project mission”, the 18 CSFs were organized into four categories: Stakeholder Interests and Relationships, Refining Goals and Managing Stakeholder Needs, Identifying and Engaging Stakeholders, and Stakeholders’ Social Responsibilities. A framework is proposed for successful stakeholder management in construction projects incorporating these four components and their relationships. These findings elucidate thigh priority aspects and may also be utilized as a tool for evaluating the success of stakeholder management, hence facilitating the identification of areas for improvement.

Background: Vesicovaginal fistula (VVF) is a debilitating conditionleaving the effected female incontinent of urine. There has been a shift in the etiology of VVF in developing nations where hysterectomy is becoming a leading cause of VVF. Objective: To share our experience of transvaginal repair of VVF using a modifiedLatzko technique and evaluate various factors for a successful repair. Study type,settings& duration:This retrospective study was carried out at the Department of Urology and Kidney Transplantation, Fauji Foundation Hospital, Rawalpindifrom March 2010, to August 2020. Methodology:Data were collected from patients who underwent transvaginal repair of VVF by a modified Latzko technique. Data consisting of multiple variables was analyzed using SPSS version 21. For qualitative data, percentages and frequencies were given and for quantitative data mean±SD were used. A comparison of two quantitative variables was done by using an independent t-test. For categorical variables, the chi-Square test was used. The pvalue ≤0.05 was taken as statistically significant. Results:A record of 144 patients was analyzed. Multivariate analysis revealed a statistically significant relationship between etiology (p-value 0.000), location (p-value 0.002) and size of VVF (p-value0.000) and a successful repair, while number (p-value = 0.71) and VVF with a previous history of repair (p-value = 0.83) were insignificant factors. Success was observed in 98.6% while recurrence occurred in 1.4%. Conclusion:Transvaginal repair of Vesicovaginal fistula using a modified Latzko technique can be carried out in all vesicovaginal fistulae whether primary or recurrent irrespective of its aetiology, size, site and number. It has a high success rate and minimal complications.

Due to advancements in telecommunications, towers need special attention in terms of the analysis and design under wind loads. The Telecommunications Industry Association (TIA) in 2005 released a standard “TIA-222-G” which has gained a widespread reference for the analysis and design of communication towers. In 2018, TIA released the latest standard TIA-222-H. The latest TIA-222-H standard has some additional features, e.g. limit states for analysis of mounting systems, enhanced climber safety requirements, construction-related loading, etc. To date, not many studies are available describing how much change in member axial forces occurs with the tower height while using the latest standard for analysis. This study’s main objective is to provide guidelines for wind load calculation on tower body, appurtenances, and other structures and compare the member axial forces induced by the wind loads on different tower heights (40, 60, and 80 m) as per TIA-222-G and TIA-222-H standards. The procedure presented in the paper about the design calculations of wind load is a useful guide for structural engineers involved in the analysis and design of communication towers. The analysis results showed that the member axial forces increased by 22% to 37%, which can assist the practitioner in more optimized design.

Geopolymer concrete (GPC) is an environmentally friendly and sustainable concrete produced through the geopolymerization process, involving the combination of alumino silicate materials with alkaline solutions. It has unique advantage of being carbon-negative which helps reduce carbon dioxide levels in the atmosphere. One challenge with making GPC is the significant variation in compressive strength that arises from differences in constituent proportions, specimen ages, andcuring conditions. There is a need to optimize the GPC constituents to achieve the desired compressive strength. To address this issue, a comprehensive dataset comprising 1242 data points from existing literature on fly ash-based GPC (FA-based GPC) was compiled for the purpose of optimizing the constituent proportions of GPC using statistical analysis. Nine independent variables were selected to develop the predictive models for compressive strength using linear (LRA), multilinear (MRA), and non-linear (NRA) regression analyses. The models were assessed using scatter plots between experimental and predicted responses and adopting the performance criteria such as the statistical significance of the model unknowns, R2 values, root mean square error (RMSE), mean absolute error (MAE), and scatter index (SI). LRA revealed that the compressive strength of GPC is not dependent on any single independent variable. Therefore regression analysis with multiple independent variables was conducted. From MRA, ±15 % error for training dataset and (15–20) % error for validating dataset was estimated. The R2, RMSE, MAE, and SI values were found to be 0.8086, 6.11, 5.35, and 0.21. NRA predicted the compressive strength more efficiently because it provides the error ±10 % for both training and validating datasets with R2, RMSE, MAE, SI values of 0.8321, 5.46, 4.77, and 0.19. Further, curing temperature, specimen age, Na2SiO3/NaOH ratio, I/b ratio, and aggregate content were found as the most significant independent variables. The time and cost-effective design mix for FA based GPC can be prepared using the regression models presented in the current work.

This work explored Phyla nodiflora (L.) Greene as a potential source of the bioactive medicinal agent. In this aspect, methanol (PN-M) and dichloromethane (PN-D) extracts were prepared from the whole plant and evaluated for phytochemical composition (total bioactive contents, UHPLC-MS analysis, and HPLC-PDA polyphenolic quantification), biological (antioxidant and enzyme inhibition) potential and in-vivo toxicity. The PN-M was found to contain higher phenolic (26.08 mg GAE/g extract) and flavonoid (50.25 mg QE/g extract) contents which might correlate to the higher radical scavenging (DPPH: 52.94 mg TE/g extract; ABTS: 72.11 mg TE/g extract) and reducing power (FRAP: 71.96 mg TE/g extract; CUPRAC: 142.65 mg TE/g extract) antioxidant potential, as well as AChE (4.33 mg GALAE/g extract), tyrosinase (125.36 mg KAE/g extract), and amylase (1.86 mmol ACAE/g extract) inhibition activity of this extract. In contrast, the PN-D extract was found to be most active for phosphomolybdenum (1.30 mg TE/ g extract) and metal chelation (54.84 mg EDTAE/g extract) assays in addition to BChE (4.70 mg GALAE/g extract) and glucosidase (0.62 mmol ACAE/g extract) enzyme inhibition activity. The PN-M extract on UHPLC-MS analysis revealed the tentative identification of 24 different secondary metabolites, most of which belonged to the flavonoid, glycoside, and terpenoid classes of phytochemicals. The polyphenolic composition of the extracts was appraised by HPLC-PDA. Seven phenolic compounds were identified in the extracts. PN-M was found to be rich in catechin (0.25 µg/extract) and 3-OH benzoic acid (0.64 µg/extract), while PN-D contained epicatechin (0.30 µg/extract), 3-OH-4-MeO benzaldehyde (0.21 µg/extract), and 2,3-Di-Meo benzoic acid (0.97 µg/extract) in higher amounts. The methanol extract was found to be non-toxic even at higher doses. Furthermore, the relationship between the phytochemicals and the tested enzymes was highlighted by molecular docking studies. In sum, this research showed that the studied extracts were effective as enzyme inhibitors and antioxidants, suggesting it would be worth investigating in more depth for further advanced studies to explore its pharmacological properties.

In the recent years, micronutrients play an important role in improving body health with preventing and treating of chronic diseases. Chromium is one of the vital minerals involved in the regulation of insulin action. According to abundant evidences this mineral seems to be an essential factor involved in the reduction of insulin resistance and decreasing the risk of type 2 diabetes mellitus (T2DM) and cardiovascular diseases (CVDs). Moreover, it has been proposed that Chromium supplementation affects mechanisms involved in blood pressure, lipid metabolism, inflammation, and oxidative stress. For instance, it may affect blood pressure through alteration of the renin-angiotensin system, as well as reducing the angiotensin-converting enzyme activity. Furthermore, Chromium supplementation might help reduce the coronary heart disease rates. This study aims to provide a comprehensive review regarding to the effects of Chromium supplementation on CVDs risk factors with an emphasis on possible molecular mechanisms.

Burnt clay brick is one of the oldest and most widely used construction materials. The production of burnt clay bricks with various waste materials can help reduce the environmental hazards and improve brick performance at low manufacturing costs, thereby leading towards more sustainable construction. This research aimed to evaluate the effect of using waste marble powder (WMP) in varying percentages, i.e., 0, 3, 6, 9, 12, and 15%, by weight of clay in an industrial brick kiln plant. A range of mechanical and durability tests was performed on the raw material, i.e., clay, WMP, and bricks, to quantify their performance. It was observed that incorporation of WMP resulted in a reduced unit weight of the bricks, making the structure lighter in weight. Moreover, compressive strength and freeze thaw test results for all the brick specimens and sulfate tests for the brick specimens with 12% WMP addition were within the Building Code of Pakistan, and ASTM C67 prescribed limits. Finally, it can be concluded that WMP up to 12% by weight of clay can be incorporated to prepare burnt clay bricks, which can reduce the environmental waste to achieve sustainability and economy for the brick industry.

Alternative fuels have garnered significant attention due to the depletion of petroleum sources and growing environmental concerns. Biodiesel, a renewable fuel, holds potential as a viable substitute for fossil fuels. Recent advancements in nanotechnology have made nanoparticle fuel additives for internal combustion engines feasible. Previous research has shown that these additives can enhance engine performance. In this experimental study, we investigated the effects of incorporating aluminium oxide nanoparticles (Al2O3) into a JB30 fuel blend (30% Jatropha biodiesel + 70% diesel) to assess potential performance improvements and reduced noise emissions. Our tests employed a 4-stroke, single-cylinder diesel engine operating at a constant speed of 1350 rpm. The JB30 blend was subjected to a 50 ppm dose of Al2O3 nanoparticles using an ultrasonicator. Results indicate that brake-specific fuel consumption (BSFC) improved for the DF70JB30 blend and further improved for the DF67JB30 blend with Al2O3 nanoparticles. Compared to pure diesel fuel, the brake thermal efficiency (BTE) increased by 3.77% for DF70JB30 and by 3.82% for DF67JB30Al2O3. Noise emissions, a crucial factor influenced by the fuel type, were lower for all blended fuels compared to pure diesel fuel (DF). The addition of nanoparticles also contributed to a reduction in the combustion pressure rise rate, resulting in decreased combustion noise. Based on these findings, it can be concluded that both the binary blend DF70JB30 and the ternary blend DF67JB30Al2O3 can be used in diesel engines without necessitating any adjustments. However, DF67JB30Al2O3 demonstrated superior outcomes when compared to DF70JB30.

The assessment of in situ permeability of rock mass is challenging for large-scale projects such as reservoirs created by dams, where water tightness issues are of prime importance. The in situ permeability is strongly related to the frequency and distribution of discontinuities in the rock mass and quantified by rock quality designation (RQD). This paper analyzes the data of hydraulic conductivity and discontinuities sampled at different depths during the borehole investigations in the limestone and sandstone formations for the construction of hydraulic structures in Oman. Cores recovered from boreholes provide RQD data, and in situ Lugeon tests elucidate the permeability. A modern technique of multivariate adaptive regression splines (MARS) assisted in correlating permeability and RQD along with the depth. In situ permeability shows a declining trend with increasing RQD, and the depth of investigation is within 50 m. This type of relationship can be developed based on detailed initial investigations at the site where the hydraulic conductivity of discontinuous rocks is required to be delineated. The relationship can approximate the permeability by only measuring the RQD in later investigations on the same site, thus saving the time and cost of the site investigations. The applicability of the relationship developed in this study to another location requires a lithological similarity of the rock mass that can be verified through preliminary investigation at the site.