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The traditional Japanese river training structure, known as “Seigyu”, designed to divert flow, reduce flow velocity, and promote geomorphological changes, is expected to contribute to the management of river morphology. Seigyu is highly impervious at the bottom giving it a unique function. Twelve Seigyus were installed in the Kizu River in Japan to assess their ability to serve as a sediment management structure, which is necessary when considering sediment replenishment from upstream dams constructed upstream. Images and videos were recorded by a UAV to assess the flow and morphology around Seigyu via image-based analysis. Additionally, the shift in its function caused by the transformation of Seigyu itself, such as tilting and clogging, was investigated. The detected geomorphological changes indicated that Seigyu contributed to the formation of complex morphological patterns and the continuous shift in the sediment budget from erosional to depositional. Even after tilting approximately 25°, Seigyus’ effects were sustained. High-velocity flow, which occurred between two Seigyus in the early stages after implementation, did not appear or at least decreased in velocity after debris was trapped between the Seigyus. These results suggest that the effects of Seigyu persist even after its transformation, and future simulations and implementations should consider these changes.

Study region: Many reservoirs worldwide experience the challenge of managing woody debris and determining the feasible location to set a floating barrier as a mitigation strategy to restrict their progression towards the dam. While the turbidity current plunges along the reservoir bed to form the underflow mud layer, the reverse current generated in the plunging flow region holds the woody debris. Study focus: The present study attempts to define the plunging zone in correlation with the floating woody debris based on field observations, densimetric Froude number, plunging formula, and entrainment formula to investigate the plunge point location. When woody debris is carried by the sediment-laden inflow through the reservoir, the volume of woody debris needs to be estimated and extracted after the flood recession. New hydrological insight for the region: According to the results of the analysis, the plunge point location was suggested as the critical condition of the densimetric Froude number for a floating barrier setup. Two proposed equations are presented to identify the turbidity current vertical profiles of velocity and sediment concentration. Considering hydrological conditions, the inflow peak sediment yield has added an optimal quantitative estimation of woody debris volumes than that by inflow peak discharge, total inflow sediment yield, maximum rainfall intensity, and total rainfall. The presented threshold values of hydrological patterns can serve as a critical warning indicator for the preparation of extraction operations for floating woody debris.

Study region: The Miandoab aquifer, northwest of Iran, which is located in a sub basin of the Urmia Lake. Study focus: To model the groundwater (GW) quantity and quality, shallow learning (Feed Forward Neural Network (FFNN), Adaptive neuro fuzzy inference system (ANFIS), Support Vector Regression (SVR)), their ensemble and deep learning models were applied. Projections by General Circulation Models (GCMs) for the Shared Socio-economic Pathways (SSP585) scenario, after bias correction, and changes of the model inputs including Normalized Difference Vegetation Index (NDVI), Gravity Recovery and Climate Experiment (GRACE), GRACE Follow-On (GRACE-FO) and GW level (GWL) obtained via Markov Chain model were employed for future climate change projections. To project GW quality (GWQ) parameters for future climate conditions, relationships between GWL and GWQ were established via the Fourier model. New hydrological insights for the region: Results revealed that ensemble learning could outperform individual methods up to 23 %. The Hydro-chemical Facies Evolution (HFE) diagrams for 2050 and 2100 indicated that clusters near the shoreline may exhibit severe declining trend in GWL up to 1.53 m and potential intrusion of saltwater. In the higher altitude lands GWL may exhibit declining trend up to 11.74 m. In addition, HFE diagram indicated that the Ca-Cl water type will be more common in 2050.

Introduction. Phenols are one of the main organic components present in the effluents of many industrial enterprises. However, the discharge of wastewater containing phenol is a priority due to its high toxicity to humans and animals, even at low concentrations. Activated carbon (AC) adsorption, which is one of the advanced purification processes, is widely used to purify water pollutants and the production of activated carbon from several carbon by-products of agriculture was also reported. In this regard, the purpose of this research was to study the adsorption of phenol on activated carbon based on date palm branches (DPB-AC) as a low-cost adsorbent.Materials and methods. DPB was used as a raw material for the production of AC by chemical activation of H3PO4. Adsorption experiments were carried out in batches. The kinetics and isotherms of adsorption were also investigated.Results. DPB-AC was obtained by chemical activation of date palm branches using H3PO4 (600 ℃, 60 min), and the specimen was designated as (DPB-AC-H3PO4). The results showed an AC yield of 52.7 %. The maximum efficiency of phenol adsorption was achieved at pH 7. In addition, phenol adsorption was well described by the kinetics of the pseudo second order with K2 = 0.0503 g/(mg·min). The phenol adsorption isotherm model followed the Langmuir model, where R2 was 0.9215 and KL = 0.0161 l/mg at 180-equilibrium time. The maximum adsorption capacity of phenol was 77.52 mg/g (mg of phenol absorbed/g of DPB-AC-H3PO4), which is a high value compared to many other results presented in the literature.Conclusions. In general, the results indicate that AC obtained from date palm branches can be a promising material for wastewater treatment, as well as an effective means to solve environmental pollution problems.

5,6,7,8-Tetrahydroquinazolin-2-(thio)-ones (THQ) fits the class of N-heterocycles as a structural core in numerous bioactive compounds. They promptly extended previous decades. They were significantly recognized in combinatorial chemistry and materials science to determine the drug discovery, antioxidants, and pharmaceuticals fields. In the present work, one-pot multicomponent sustainable synthesis of THQ with easily accessible starting materials, i.e., cyclohexanone, different aromatic aldehydes and (thio)urea, has been performed to determine the proposed Biginelli mechanism that is supported by DFT. It is found that the THQs are synthesized by a mechano-chemical (grinding) tool to achieve a yield of 85.2% within 3.5 min, i.e., YE (% yield/time) 24.34 differs from the conventional method in which lower % yield (YE = 0.72) of THQ was achieved. This confirmed that in the green chemistry principle, the determination of % yield according to saving reaction time must be considered. Moreover, DFT-based antioxidant properties of the THQ were also studied in which the most potent antioxidant compounds were 7b > 6d > 2f. Softness (σ, eV−1) and hardness (η, eV mol−1) can approve the soft molecule that stays more reactive as a result of decreasing the energy gap along heterocyclic with values 0.1491 > 0.1300 > 0.1168 eV−1 one-to-one with the efficiency of antioxidant.

Despite their popularity, the construction and operation of hydropower reservoirs pose challenges to water resources. This study investigated the impacts of cascading dams on streamflow in Tanzania’s Rufiji River Basin. The SWAT model was developed to represent the entire Rufiji River Basin. The model simulated the streamflow for 41 years, from 1982 to 2022, and developed two main scenarios: with-dam and without-dam. To capture the influence of all dams, the results were emphasized from 2000 to 2022, when all three dams were operating. Calibration and validation were applied at the Rufiji-Stiegler and Kilombero-Swero stations with good performance. The results show that cascading dams annually decrease the streamflow by 1% at Rufiji-Stiegler station. In contrast, individually, the Mtera Dam displayed a 5% decrease while the Kidatu and Kihansi Dams exerted a 1% increase on the annual streamflow downstream at Rufiji-Stiegler. During 2000–2022, the Rufiji River Basin showed an annual reduction in streamflow contribution of 104.97 m3/s. Therefore, the reservoir’s operation significantly impacts the downstream streamflow. The findings are expected to guide policymakers, water resource managers, and environmentalists in mitigating potential adverse effects while optimizing the benefits of hydropower generation and water regulation within the region.

Abstract Background Whole-body diffusion-weighted magnetic resonance is being developed as a tool for assessing tumor spread. Patients with known primary tumors require meticulous evaluation to assess metastasis for better staging; we attempted to detect bony metastasis without radiation exposure. Our study's goal was to use whole-body diffusion-weighted imaging with background body signal suppression (WB-DWBIS) to evaluate bony metastasis in confirmed patients who have primary tumors. Results Our study included 90 patients with known primary cancer, 10 patients were excluded as they had no bony metastasis, from 80 patients: 36 (45.0%) having one site of metastasis, 36 (45%) having two sites of metastasis, and 8 (10.0%) having three sites of metastasis. 56 (70.0%) of the metastasis sites were bony metastasis, and 76 were mixed both bony and non-bony, including 32(40.0%) lung, 16 (20.0%) liver, and 28 (35%) lymph nodes. Sensitivity of bone scanning in detecting metastasis was as follows: 95.1% sensitivity and 92.0% accuracy, while that of whole-body diffusion-weighted image with background signals suppression was 94.8% sensitivity and 91.7% accuracy, WB-DWBIS inter-observer agreement in the detection of bony metastatic deposits in cancer patients was good (0.7 45, agreement = 93.2%). Conclusions Using WB-DWBIS images, bone lesion identification and characterization (site and number) were improved, producing outcomes similar to bone scanning without the use of ionizing radiation.

Understanding the complexity of the siltation process and sediment resuspension in shallow reservoirs is vital for maintaining the reservoir functionality and implementing sustainable sediment management strategies. The geometry of reservoirs plays an indispensable role in the appearance of various flow structures inside the basin and, consequently, the pattern of the morphological evolution. In this study, a three-dimensional numerical model, coupled with optimization algorithms, is used to investigate the morphological bed changes in two symmetric shallow reservoirs having hexagon and lozenge shapes. This work aims to evaluate the applicability, efficiency, and accuracy of the automatic calibration routine, which can be a suitable replacement for the time-consuming and subjective method of manual model calibration. In this regard, two sensitive parameters (i.e., roughness height and sediment active layer thickness) are assessed. The goodness-of-fit between the calculated bed levels and the measured topography from physical models are presented by different statistical metrics. From the results, it can be concluded that the automatically calibrated models are in reasonable agreement with the observations. Employing a suitable optimization algorithm, which finds the best possible combination of investigated parameters, can considerably reduce the model calibration time and user intervention. HIGHLIGHTS The flow structure and sedimentation pattern in symmetric expansions are numerically studied.; Local (GML) and a global (BB–BC) optimization algorithms are used to calibrate the numerical models of two symmetric shallow reservoirs.; GML outperforms BB–BC considering the convergence speed (efficiency) without trapping in local minima by having the same predicted parameter values (robustness).;

Abstract The current paper discusses the numerical simulation results of the NePCM melting process inside an annulus thermal storage system. The TES system consists of a wavy shell wall and a cylindrical tube equipped with three fins. The enthalpy-porosity method was utilized to address the transient behavior of the melting process, while the Galerkin FE technique was used to solve the system governing equations. The results were displayed for different inner tube positions (right-left–up and down), inner cylinder rotation angle (0 ≤ α ≤ 3π/2), and the nano-additives concentration (0 ≤ ϕ ≤ 0.04). The findings indicated that high values of nano-additives concentration (0.4), bigger values of tube rotation angle (3π/2), and location of the tube at the lower position accelerated the NePCM melting process.

Abstract Background Magnetic resonance imaging is regarded as one of the most important markers for multiple sclerosis. It can detect lesions in order to establish dissemination in time and space, which would aid in the diagnosis. Two-dimensional FLAIR is a standard sequence in MS routine imaging because it suppresses cerebrospinal fluid signal, increasing contrast between lesions and CSF and improving white matter lesion detection. Newer 3D FLAIR sequences are expected to offer even more benefits, such as improved MS lesions detection and higher resolution due to thinner slice thickness. We aimed to compare the role of 3D Cube FLAIR imaging (versus standard 2D FLAIR) in the assessment of white matter lesions in MS patients, as well as to test the convenience of using maximum intensity projection (MIP) on 3D FLAIR images for faster and easier evaluation. Results This study included 160 MS patients. A 1.5 T routine brain MRI scan was performed, which included a 2D FLAIR sequence, followed by a 3D-FLAIR sequence. All images were analyzed after 3D-FLAIR images were reformatted into axial MIP images. Lesions were counted in each sequence and classified into supra-tentorial (periventricular, deep white matter, and juxta-cortical), and infra-tentorial lesions, with the relative comparison of lesions numbers on 3D-FLAIR and MIP versus 2D-FLAIR expressed as a percentage increase or decrease. 3D FLAIR can significantly improve MS lesion detection in all areas of the brain when compared with 2D FLAIR results. At 2 mm reformatting, there is no difference in MS lesion detection between sagittal 3D FLAIR and axial MIP reconstruction, implying that the MIP algorithm can be used to simplify lesion detection by reducing the number of images while maintaining the same level of reliability. Conclusion 3D FLAIR sequences should be added to conventional 2D FLAIR sequences in the MRI protocol when MS is suspected.

Sharp-crested weirs are commonly used in hydraulic engineering for flow measurement and control. Despite extensive research on sharp-crested weirs, particularly regarding their discharge coefficients, more information is needed via research on their energy dissipation downstream. This study conducted experimental tests to assess the influence of contraction ratio (b/B) of rectangular sharp-crested weirs (RSCWs) on energy dissipation downstream under free flow conditions. Five RSCWs with different b/B equals 6/24, 7/24, 8/24, 9/24, and 10/24 were used. The results showed a consistent decrease in relative energy dissipation (ΔEr) with an increase in the head over the weir. Furthermore, as the discharge per unit width (q) increased, the relative energy dissipation (ΔEr) decreased, indicating more efficient discharge over the weir. A higher b/B further reduces ΔEr, suggesting that wider weirs are more effective in minimizing energy losses. The maximum relative residual energy (E1/E0) and relative energy dissipation (ΔEr) occurred at b/B = 10/24 and 6/24, with values of 0.825 and 0.613, respectively. Additionally, the maximum discharge coefficient (Cd) of RSCWs is found at b/B = 6/24, with an average value of 0.623. The results support the accuracy of the proposed equation with R2 = 0.988, RMSE = 0.0083, and MAPE = 1.43%. [ABSTRACT FROM AUTHOR]

A rectangular slit weir is used to measure small flows, namely, those flows less than 5 L/s and contraction ratios (b/B) less than 0.25. In the present study, flow tests were conducted in a laboratory setup with various contraction ratios (b/B) under models A (b/B = 1/12), B (b/B = 1/8), C (b/B = 1/6), D (b/B = 5/24), and E (b/B = 1/4). The dimensional analysis revealed that b/B, the height of the flow on the crest of the weir to the height of the weir crest (h/P), the Reynolds number (Re), and the Weber number (We) are effective parameters for predicting the discharge coefficient of the slit weir. The experimental results indicated that the discharge coefficient is variable for different contraction ratios; the maximum average discharge coefficient was achieved at the lowest b/B (Model A), with a value of 0.72. The minimum average discharge coefficient obtained in Model B equals 0.639. In addition, former prediction equations were compared with the obtained experimental data, and the minimum, average, and maximum errors were calculated. Furthermore, a relationship was established for deriving the discharge coefficient in slit weirs with R2 = 0.9212, RMSE = 0.02244, and MAE = 0.0134 based on the obtained experimental data with four effective parameters, b/B, h/P, Re, and We. [ABSTRACT FROM AUTHOR]

Bovine theileriosis, babesiosis and anaplasmosis are tick-borne hemoparasitic diseases and they are responsible for huge economic losses in livestock sector in Egypt. Currently, a total number of 110 dairy cows from different regions of Qena governorate, Egypt, were clinically and laboratory investigated for diagnosis of theileriosis, babesiosis and anaplasmosis using Giemsa stained blood film and Polymerase Chain Reaction (PCR) assay during the period from January 2019 to December 2019. On the basis of the obtained results, the overall prevalence of babesiosis, theileriosis and anaplasmosis among the screened cattle was 9.09%, 21.81%, and 25.45 respectively. Furthermore, mixed infections were seen in nineteen cases (17.27%) on the basis of blood film examination. PCR assay results revealed that, the infection rate with theileriosis, babesiosis and anaplasmosis was 5.45%, 7.27% and 16.36%, respectively. While, 7 cows were found to harbor a mixed infection. Additionally, hemato-biochemical alternations in theileriosis, babesiosis and anaplasmosis infected cows were also detected in this study. It could be concluded that PCR assay was the most sensitive test in the detection of the infection in all cases of the disease (acute, chronic and carriers) as once animals infected, they become carriers with low parasitemia after recovery and this low parasitemia cannot be detected by traditional examination of Giemsa stained thin blood smears.

Reservoirs have been installed as long-term assets to guarantee water and energy security for decades, if not centuries. However, the effect of siltation undermines reservoirs' sustainability because it significantly reduces the reservoirs' original capacity. Extreme events such as typhoons, floods and droughts are posited to have extreme impacts on sediment inflow and deposition in reservoirs. The same holds true for ISMTs (implemented sediment management technologies), such as dredging, spilling and bypassing. However, the large-scale analysis of their effects on reservoir sedimentation progression, recovery and development was not feasible due to data scarcity and technological restrictions. The present paper closes this information gap by conducting a GRU (gated recurrent unit) neural network analysis of 1,224 Japanese reservoirs, for which the sedimentation, local precipitation, extreme events and ISMTs were monitored between 2000 and 2017. The network reveals the beneficial impacts of dredging, spilling and bypassing. The results also demonstrate the potential of smart management and improved monitoring for sedimentation threat abatement. Thus, foresighted engineering and dedicated governance action in flood and drought scenarios can significantly strengthen the sustainable behavior of key infrastructure elements such as reservoirs. HIGHLIGHTS Unique data set: 1,225 dams with 18 years of sediment record each.; Anti-sediment management notations.; Artificial neural networks with gated recurrent units as methodology.; Unique conclusions regarding the efficiency of sediment management methodology.; Generalized results represent multifaceted types of reservoirs.;

This study investigates the impact of climate change on hydrological dynamics in the Ruzizi River Basin (RRB) by leveraging a combination of observational historical data and downscaled climate model outputs. The primary objective is to evaluate changes in precipitation, temperature, and water balance components under different climate scenarios. We employed a multi-modal ensemble (MME) approach to enhance the accuracy of climate projections, integrating historical climate data spanning from 1950 to 2014 with downscaled projections for the SSP2-4.5 and SSP5-8.5 scenarios, covering future periods from 2040 to 2100. Our methodology involved calibrating and validating the SWAT model against observed hydrological data to ensure reliable simulations of future climate scenarios. The model's performance was assessed using metrics such as R2, NSE, KGE, and PBIAS, which closely aligned with recommended standards. Results reveal a significant decline in mean annual precipitation, with reductions of up to 37.86% by mid-century under the SSP5-8.5 scenario. This decline is projected to lead to substantial reductions in surface runoff, evapotranspiration, and water yield, alongside a marked decrease in mean monthly stream flow, critically impacting agricultural, domestic, and ecological water needs. The study underscores the necessity of adaptive water resource management strategies to address these anticipated changes. Key recommendations include implementing a dynamic reservoir operation system, enhancing forecasting tools, and incorporating green infrastructure to maintain water quality, support ecosystem resilience, and ensure sustainable water use in the RRB. This research emphasizes the need for localized strategies to address climate-driven hydrological changes and protect future water resources. [ABSTRACT FROM AUTHOR]

Abstract The phase stability and microstructure of ZrO2–5CaO and ZrO2–24MgO mixed coating (wt%) by air plasma spraying on 304 stainless steel substrates were investigated. A Ni–5Al (wt%) metallic bond coating was firstly sprayed between the substrate and the ceramic top layer. The results were compared with the individual coatings of ZrO2–5CaO and ZrO2–24MgO for a better understanding of the correlation between their microstructures and mechanical properties. Mixed zirconia coating was found to have a mixture of cubic and tetragonal phases that stabilized under different plasma spray conditions. Microscopic observations and elemental composition analysis of as-sprayed mixed coating showed that modified ceramic-matrix grains had been formed. Microsized ZrO2–5CaO particles were embedded in the matrix grain creating an intragranular microstructure. Results indicated that ceramic-matrix grains provided a diffusion barrier for the growth of oxides induced stress near and onto the bond layer that reduced cracks, thereby overcoming the top delamination of the ceramic coating. Moreover, disparity in wear resistance and microhardness behavior of the coatings was influenced by initial feedstock powder and matrix microstructures. Improvement in the wear resistance of the mixed zirconia coating was attributed to a decrease in oxide content, which resulted in an increase in intersplat cohesive strength.

Reservoirs are installed as long-term assets to guarantee water and energy security for decades, if not centuries. However, the effect of siltation undermines reservoirs’ sustainability because it significantly reduces the reservoirs’ original capacity. The present paper attempts to evaluate the global reservoir siltation problem with the optimism bias theorem introduced by Kahneman and Tversky and applied to infrastructural mega-projects by Flyvbjerg and Ansar using artificial neural networks (ANNs) algorithms for large Japanese reservoirs. Japan possesses suitable long-term data and a legal directive concerning the sediment capacity siltation duration, which serves as a valid guide to check whether, over the past 100 years, engineers, planners and managers were capable of judging the sediment input correctly. Various ANN models were established to emulate Japanese reservoir siltation behavior. The networks demonstrate that reservoirs in Japan suffer from optimism bias. In contrast to the law, the dead storage volume of an average dam is supposed to reach capacity after 52 years. This finding joins the overall observation that mega-projects generally and globally suffer from optimism bias. The emulations were subsequently screened for a presumed influence of governance actions, namely, indicating plus monitoring and the change in the market competition situation. While reservoir siltation appears to continue regardless of the level of competition in public procurement, monitoring directives appear to have a considerable impact on improved siltation management, which demonstrates that dedicated governance action can significantly strengthen the sustainable behavior of key infrastructure elements such as reservoirs.

This research introduces new pedagogical approach, the Virtual Flipped Classroom (VFC). The VFC is an integration of two concepts: Flipped Classroom and Virtual Classroom. It enables the teachers to teach and guide the students in applying the activities needed to achieve best learning levels. To investigate the effect of VFC, the researchers applied it on the students of computer programming course in Instructional and Learning Technology (ILT) department at College of Education, Sultan Qaboos University (SQU). The students’ learning achievement and motivation were measured by two instruments, Programming Achievement Test and Survey of Student Motivation respectively. One-group pretest-posttest qusai-experimental design has been followed. The sample, which consisted of 18 students, was taught some selective topics of the computer programming perquisite using the VFC model. A pretest and posttest are administered before and after using the VFC model. The researchers used independent sample t-test and multivariate analysis of variance (MANOVA) to analyze the data obtained. Findings indicated a significant difference in the learning achievement and motivation before and after applying the VFC model. The differences were in favor of VFC model. Further analysis showed that the new model contributed to the improvement of performance of low achievers students.