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Endophytic bacteria have not been reported widely for their lipolytic abilities, so they are not used for large‐scale lipase production. The purpose of this study was to explore an endophytic bacterium for the production of lipase implementing cost‐effective techniques, including the use of Cassia fistula seeds, as a substrate in the production medium and stem pieces of Phragmites karka as the immobilization matrix. The endophytic strain Bacillus sp. E4 was originally isolated from the halophytic plant Arthrocnemum macrostachyum. Bacillus sp. E4 produced 6.05 IU mL−1 lipase in the presence of powdered seeds of Cassia fistula (golden shower tree). Initial trial experiments using a one‐factor‐at‐a‐time approach led to an improvement in lipase titers to 10.05 IU mL−1. Consequently, investigations using the Plackett–Burman design suggested the influence of three significant factors – incubation period, inoculum size, and substrate concentration – on lipase production. They were optimized using the Box–Behnken design (BBD). In the response optimization experiment, strain E4 yielded 52.35 IU mL−1 lipase, which was in accordance with the predicted yield and indicated an overall 8.65 fold improvement in lipase production. To investigate the use of free cells, strain E4 was immobilized on the stem pieces of a halophytic plant, Phragmites karka, which was used for the first time as an immobilization matrix. The immobilized cells retained lipase production ability for up to six cycles with the highest yield of 110 IU mL−1, which corresponded to an improvement of more than eighteenfold. Scanning electron micrographs confirmed the colonization of E4 cells in the matrix and demonstrated the utilization of C. fistula seeds. Fourier transform infrared spectroscopy affirmed the utilization of components including fatty acids by the immobilized E4 cells. The study suggests that endophytic bacterial strains could be applied for the production of lipase with the utilization of nontraditional oil sources. [ABSTRACT FROM AUTHOR]

The ever-increasing demand for electricity has presented a grave threat to traditional energy sources, which are finite, rapidly depleting, and have a detrimental environmental impact. These shortcomings of conventional energy resources have caused the globe to switch from traditional to renewable energy sources. Wind power significantly contributes to carbon-free energy because it is widely accessible, inexpensive, and produces no harmful emissions. Better and more efficient renewable wind power production relies on accurate wind speed predictions. Accurate short-term wind speed forecasting is essential for effectively handling unsteady wind power generation and ensuring that wind turbines operate safely. The significant stochastic nature of the wind speed and its dynamic unpredictability makes it difficult to forecast. This paper develops a hybrid model, L-LG-S, for precise short-term wind speed forecasting to address problems in wind speed forecasting. In this research, state-of-the-art machine learning and deep learning algorithms employed in wind speed forecasting are compared with the proposed approach. The effectiveness of the proposed hybrid model is tested using real-world wind speed data from a wind turbine located in the city of Karachi, Pakistan. Moreover, the mean square error (MSE), root mean square error (RMSE), and mean absolute error (MAE) are used as accuracy evaluation indices. Experimental results show that the proposed model outperforms the state-of-the-art legacy models in terms of accuracy for short-term wind speed in training, validation and test predictions by 98% respectively. [ABSTRACT FROM AUTHOR]

This research considers complex dynamics of life under ideal conditions in the context of development projects. Using a multidimensional analytical approach, this study explores other areas of interaction of social, economic, and environmental factors that seek an inclusive evaluation of aspirations and realities of communities undergoing change, including quantitative methods, of ideal phenomena of life. Understanding is about unraveling the complexities associated with understanding. The results are expected to contribute valuable insights into areas of development studies, urban planning, and community well-being, leading to excellent development of the variety of types of ideal living conditions in the context of aspirational development initiatives. That make a comprehensive assessment of desires and realities of communities in change through comprehensive evaluation of ideal phenomena of life, including qualitative & quantitative methods. Results are likely to contribute valuable insights in areas of development studies, urban planning, and social welfare, which will provide excellent overview of various ideal situations in context of aspirational development initiatives. [ABSTRACT FROM AUTHOR]

Due to the precarious underwater environment, many tasks are impossible to carry out with manned vehicles. It is due to the development of autonomous underwater vehicles (AUVs) that exploration, surveillance, and research have been carried out like never before. AUVs are now extensively used for lengthy missions but face challenges in maintaining an accurate position over a larger operational area due to water currents and oceanic complexities. Hence, more sophisticated navigation systems are required for AUVs. As global positioning systems (GPS) and radio signals are attenuated under water, it becomes difficult to navigate subsea areas. In this research work, we propose the accurate position estimation of an AUV by a Kalman filter using an inertial navigation system (INS). In the MATLAB environment, a sample of the INS accelerometer's data is simulated to determine position from acceleration using the Kalman filter, and the double integration method of determining position is contrasted. Our experimental results imply that our suggested method produces better outcomes. [ABSTRACT FROM AUTHOR]

In this research work, CuS and WO3 nanoparticles were synthesized by a simple, facile and effective hydrothermal method followed by the fabrication of nanocomposites of 10, 12 & 14% CuS:WO3. The prepared samples were characterized by various characterization techniques including X-ray diffraction (XRD), UV–Visible (UV–vis), photoluminescence (PL), Energy dispersive X-ray (EDX) and field emission scanning electron microscopy (FE-SEM) for the confirmation and investigation of fabricated nanocomposites. The particle size of fabricated WO3 was 46.01 nm which was reduced to 37.14 nm for 14% CuS:WO3 sample. Additionally, UV visible and PL analysis confirmed the suppression of band gap (2.61 to 2.25 eV) and photogenerated electron/hole pair respectively. Photocatalytic activity of as prepared nanocomposites was investigated under visible light irradiation against rhodamine B (RhB) dye. Quite interestingly, the photodegradation efficiency of 14% CuS-WO3 is 94.91% which is much higher as compared to pure WO3 which attributes to the smaller particle size and bad gap energy which enables the efficient utilization of visible light leading to the generation of reactive species. Reusability experiments confirmed the photostability of samples and pH tests have also been conducted to investigate the optimum pH for degradation reaction. For investigation of complete mineralization of RhB dye from contaminated water, TOC analysis has been conducted. Additionally, RF module of COMOSL Multiphysics 5.3a has been used to simulate a 2D model to correlated the experiment with the theoretical results for better understanding. [ABSTRACT FROM AUTHOR]

In this work, the hybrid WO3/titanium dioxide (TiO2) photocatalysts were prepared using hydrothermal method for the degradation of methylene blue dye under visible light irradiation. The scanning electron microscope, Fourier transform infrared spectroscopy, ultra violet visible absorption and photoluminescence emission spectroscopy were employed to study the morphology, structure and functional groups, elemental composition and purity, and optical properties. The morphological results showed the rectangular structure of pure WO3 with size of 36–550 nm, whereas spherical structures were also observed after incorporation of TiO2 in WO3. The monoclinic phase was found with high crystallinity. The composite sample (2% TiO2/WO3) showed seven times improved photocatalytic activity as compared to pure samples. The improvement may attribute to the increase of the photo-absorption effect by the TiO2, the cooperative effect of the WO3, optimal band gap and unique morphological structures. Considering our present study as cost-effective method, the as-synthesised photocatalysts can be suitable and give a new perspective for applied use in energy and environmental applications. [ABSTRACT FROM AUTHOR]

Academic stress among the students of university remained an issue that hinders their academic performance despite adequate efforts. The present study investigated the effectiveness of Cognitive Behavior Therapy (CBT) for academic stress and academic performance in university students. The research was based upon multiple case study design and the sample consisted of total 30 students with the average age range of 19 to 30 years. The Academic Stress Scale (ASS) by Kohn and Frazer 1986 was used to scrutinize subjects with higher level of stress while the academic performance was obtained from their grades from last two semesters. The selected sample was administered with the psychological treatment by utilizing two techniques of CBT (Imaginal exposure and cognitive restructuring) with 10 sessions per subject. The results of paired sample t-test showed the reduction in academic stress and an enhancement in academic performance at post-test. The study has implications and suggest future research direction. [ABSTRACT FROM AUTHOR]