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Introduction: Hydroponic cultivation systems using desalinated groundwater may play pivotal role in reducing freshwater consumption for irrigation. However, reliance on desalination remains unsustainable due to its high cost, energy demand, and the serious environmental impacts of its brine byproducts. Producing a biofertilizer that enables groundwater irrigation in hydroponics by enhancing plant halotolerance and resistance to salt stress offers a promising solution to address freshwater scarcity and low soil quality in arid and semi-arid regions, such as the Arabian Gulf. Methods: This study investigates the potential of Bacillus spizizenii FMH45 in field experiment to enhance tomato plant production under greenhouse cultivation in hydroponics using directly groundwater for irrigation without desalination. Results and discussion: Results demonstrated that the FMH45-based biofertilizer (HB45) significantly improved plant physiological parameters under greenhouse conditions. These improvements included a notable increase in shoot elongation (>13%), enhanced SPAD index values (>8%), and significant rises in flower and fruit counts (≃ 11% and 22%, respectively). B. spizizenii HB45 showed significant potential to increase bacterial densities by over 100-fold in various plant organs under saline irrigation and prevent salt infiltration into internal plant tissues. Furthermore, HB45-treatment enhanced the plant oxidative stress response as evidenced by stable catalase activity, an approximately 50% reduction in lipid peroxidation markers such as malondialdehyde (MDA), and a 35% decrease in reactive oxygen species (ROS), including hydrogen peroxide (H2O2). These findings demonstrate that B. spizizenii FMH45 holds significant potential for the development of effective biofertilizers capable of mitigating salt stress while boosting crop productivity. This approach offers a sustainable alternative to desalination-dependent hydroponics, particularly for arid and semi-arid regions, including Qatar. [ABSTRACT FROM AUTHOR]

There is limited research focused on achieving optimal torque control performance of Switched Reluctance Generators (SRGs). The majority of existing studies tend to favor voltage or power control strategies. However, a significant drawback of SRGs is their susceptibility to high torque ripple. In power generation systems, torque ripple implicates fluctuations in the generated power of the generator. Moreover, high torque ripple can lead to mechanical vibrations and noise in the powertrain, impacting the overall system performance. In this paper, a Torque Sharing Function (TSF) with Indirect Instantaneous Torque Control (IITC) for SRG applied to Wind Energy Conversion Systems (WECS) is proposed to minimize torque ripple. The proposed method adjusts the shared reference torque function between the phases based on instantaneous torque, rather than the existing TSF methods formulated with a mathematical expression. Additionally, this paper introduces an innovative speed control scheme for SRG drive using a Fuzzy Super-Twisting Sliding Mode Command (FSTSMC) method. Notably robust against parameter uncertainties and payload disturbances, the proposed scheme ensures finite-time convergence even in the presence of external disturbances, while effectively reducing chattering. To assess the effectiveness of the proposed methods, comprehensive comparisons are made with traditional control techniques, including Proportional–Integral (PI), Integral Sliding Mode Control (ISMC), and Super-Twisting Sliding Mode Control (STSMC). The simulation results, obtained using MATLAB®/SIMULINK® under various speeds and mechanical torque conditions, demonstrate the superior performance and robustness of the proposed approaches. This study presents a thorough experimental analysis of a 250 W four-phase 8/6 SRG. The generator was connected to a DC resistive load, and the analysis focuses on assessing its performance and operational characteristics across different rotational speeds. The primary objective is to validate and confirm the efficacy of the SRG under varying conditions.

Nowadays, transformer-less photovoltaic (PV) multi-level inverters (MLIs) are commonly employed in both industrial and residential settings. This structure has attracted increased attention due to its unique advantages, such as higher efficiency, lower cost and size, better waveform quality, and inherent fault tolerance. However, due to the removal of the transformer, the common mode voltage (CMV) becomes one of the crucial issues in transformer-less PV MLIs. The high-frequency variation in CMV results in a leakage current that deteriorates the line current quality, increases the PV power system losses, leads to severe electromagnetic emissions (EMI), reduces the PV array lifespan, and causes personal safety problems. In this regard, this paper presents a review of the existing and recent research on modulation techniques based on space vector pulse width modulation (SVPWMs) that overcome this issue in transformer-less three-level NPC-MLIs (3L-NPC-MLIs). The reduced CMV-SVPWM (RCMV-SVPWM) can be mainly categorized as an RCMV-SVPWM based on the vector type, based on virtual vectors, and based on the two-level SVPWM (2L-SVPWM). Their features and their limitations in terms of several main criteria are discussed. In the final section of this paper, some challenges and future trends for this research area are projected.

Abstract This study appraised and compared the performance of process-based hydrological SWAT (soil and water assessment tool) with a machine learning-based multi-layer perceptron (MLP) models for simulating streamflow in the Upper Indus Basin. The study period ranges from 1998 to 2013, where SWAT and MLP models were calibrated/trained and validated/tested for multiple sites during 1998–2005 and 2006–2013, respectively. The performance of both models was evaluated using nash–sutcliffe efficiency (NSE), coefficient of determination (R 2), Percent BIAS (PBIAS), and mean absolute percentage error (MAPE). Results illustrated the relatively poor performance of the SWAT model as compared with the MLP model. NSE, PBIAS, R 2, and MAPE for SWAT (MLP) models during calibration ranged from the minimum of 0.81 (0.90), 3.49 (0.02), 0.80 (0.25) and 7.61 (0.01) to the maximum of 0.86 (0.99), 9.84 (0.12), 0.87 (0.99), and 15.71 (0.267), respectively. The poor performance of SWAT compared with MLP might be influenced by several factors, including the selection of sensitive parameters, selection of snow specific sensitive parameters that might not represent actual snow conditions, potential limitations of the SCS-CN method used to simulate streamflow, and lack of SWAT ability to capture the hydropeaking in Indus River sub-basins (at Shatial bridge and Bisham Qila). Based on the robust performance of the MLP model, the current study recommends to develop and assess machine learning models and merging the SWAT model with machine learning models.

In the current study, three machine learning (ML) models, i.e. Gaussian process regression (GPR), generalized regression neural network (GRNN), and multigene genetic programming (MGGP), were developed for predicting the discharge coefficient (Cd) of a radial gate under two different flow conditions, i.e. free and submerged. The modeling development of the flow and geometry input variables for the Cd was determined based on statistical correlations. We also performed a sensitivity analysis of the input variables for the Cd. The modeling results indicated that the developed ML models attained acceptable predictable performance; however, the prediction accuracy of the models was better under the free flow condition. In quantitative terms, the minimum root mean square error (RMSE) value was 0.010 using the GPR model and 0.019 using the MGGP model for the submerged and free flow conditions, respectively. The sensitivity analysis evidenced that the ratio of the gate opening height to the depth of water in the upstream (W:Yo) was the influential variable for the Cd under the free flow condition, whereas the ratio of the depth of water in the upstream to the depth of water in downstream (Yo:YT) was the influential variable for the Cd under the submerged flow condition.

It's undeniably true that fractional calculus has been the focus point for numerous researchers in recent couple of years. The writing of the Caputo-Fabrizio fractional operator has been on many demonstrating and real-life issues. The main objective of our article is to improve integral inequalities of Hermite-Hadamard and Pachpatte type incorporating the concept of preinvexity with the Caputo-Fabrizio fractional integral operator. To further enhance the recently presented notion, we establish a new fractional equality for differentiable preinvex functions. Then employing this as an auxiliary result, some refinements of the Hermite-Hadamard type inequality are presented. Also, some applications to special means of our main findings are presented.

This article deals with the impact of including transverse ribs within the absorber tube of the concentrated linear Fresnel collector (CLFRC) system with a secondary compound parabolic collector (CPC) on thermal and flow performance coefficients. The enhancement rates of heat transfer due to varying governing parameters were compared and analyzed parametrically at Reynolds numbers in the range 5,000–13,000, employing water as the heat transfer fluid. Simulations were performed to solve the governing equations using the finite volume method (FVM) under various boundary conditions. For all Reynolds numbers, the average Nusselt number in the circular tube in the CLFRC system with ribs was found to be larger than that of the plain absorber tube. Also, the inclusion of transverse ribs inside the absorber tube increases the average Nusselt number by approximately 115% at Re = 5,000 and 175% at Re = 13,000. For all Reynolds numbers, the skin friction coefficient of the circular tube with ribs in the CLFRC system is larger than that of the plain absorber tube. The coefficient of surface friction reduces as the Reynolds number increases. The performance assessment criterion was found to vary between 1.8 and 1.9 as the Reynolds number increases.

Introduction Cervical cancer is mostly caused by high-risk Human papillomavirus HPV, with an estimation prevalence of HPV of 99.7% worldwide. The US Food and Drug Administration (FDA) approved an HPV test for primary cervical screening in 2014. An HPV-DNA test, which provides higher protection against invasive cervical carcinomas, is replacing the long-standing Pap smear as the primary method of cervical cancer screening. Objective To explore nurses’ experience and knowledge of HPV DNA testing and how screening impacts on women's health through increasing awareness and proposing actions for health education strategies. Method A qualitative exploratory study was conducted on a purposeful sample of 25 qualified nurses, who were all employed in regional hospitals within a gynecological department in Kirkuk, Iraq. The nurses were interviewed with a semi-structured topic guide between November 2021 and February 2022. Responses were transcribed verbatim, translated into English and analysed using a content thematic analysis approach. Results Four themes with associated sub-themes emerged following coding and peer review. Participants had lack of experience and fragmented knowledge of HPV DNA testing/screening. Culturally sensitive resources for patients and training for nurses was identified key requirements. Conclusions Currently, there are no facilities for a HPV testing/screening services available in Iraq. The role of nurses undertaking HPV screening is not established and yet nurses represent the largest sector of health professionals. The dissemination of a collaborative HPV screening training programme to include clinical competence and knowledge for nurses and gynaecologists may improve knowledge, and could also be effective in improving patient awareness and engagement with cervical health.

The disposal of biological waste into water bodies is a major global concern as it leads to water pollution resulting in the loss of plenty of revenue in the cleaning of water bodies. Here, in the present research work, sacred flowers were collected, segregated, sun-dried, and powdered. The dried floral powders (marigold and rose) were characterized by field emission scanning electron microscopy (FESEM), electron diffraction spectroscopy (EDS), Fourier transforms infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The microscopy revealed the irregular spherical shape of the sheet-like structure whose size varies in microns. The EDS revealed the elemental composition which was dominated by mainly carbon and oxygen. The XRD shows the presence of carbon (10-25ɵ) in the amorphous form and the absence of any crystalline phase in the biosorbents. The FT-IR showed peaks that conformed to the presence of functional groups like -OH and a carbonyl group. The dried powders were used as an economical and eco-friendly biosorbent for the removal of methyl red (MR) dye from the aqueous solutions by batch adsorption study. After 60 minutes of contact time, the marigold powder (MGP) and rose petal powder (RPP) showed decolorization of 61.16% and 56.08% for 2 ppm of MR dye. The kinetic revealed that the dye removal reaction does not follow the pseudo-first-order as well as the pseudo-second-order. The utilization of such waste-based biosorbents will minimize solid waste and also will provide an economical biosorbent for the removal of environmental pollutants.

The exposure of concrete to elevated temperatures is known to cause diverse severe damages in concrete composites. Hence, measures to improve the performance of concrete during exposure to fire are continually proposed. The present study investigated the postfire residual strength and morphology of concrete incorporating natural rubber latex exposed to elevated temperature. Four different concrete mixes were considered for the investigation, namely, a control sample made without natural rubber latex, the second sample containing 1% natural rubber latex, the third sample containing 1.5% natural rubber latex, and the fourth sample containing 3% of natural rubber latex. The concrete samples (150 mm cubes and 100 × 200 mm cylinders) were exposed to varying temperatures 300°C, 800°C, and 1000°C, after the curing process. Nondestructive tests using Schmidt rebound hammer and ultrasonic pulse tester were carried out on samples. The compressive strength and split-tensile strength of concrete cubes and cylinders, respectively, were determined. Micrographs and elemental distribution in the sample were studied using the scanning electron microscopy (SEM-EDX) apparatus. It could be seen from the results that the concrete strength properties reduced as the exposure temperature increased. The results also showed that NRL could be sparingly utilized as a concrete admixture, at 1% content. The performance of concrete was not stable at over 300°C when NRL addition was above 1%.