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Photocatalytic treatment of wastewater utilizing oxides of metals as photocatalysts has merged a subject of major concern. The photocatalytic efficiency can be increased by the separation of electrons and holes formed by the absorption of photons. The development of heterojunction between two semiconductors is one of the methods used for the separation of photo-induced electrons and holes. Herein, we report a p-n NiO-ZnO heterojunction photocatalyst for efficient photodegradation of crystal violet dye. The homogeneous precipitation method was used for the synthesis of p-n NiO-ZnO in this study. The synthesized heterojunction was characterized by XRD, SEM, EDX, and TGA techniques. The aqueous solution of crystal violet dye was used as model wastewater for the evaluation of the photocatalytic efficiency of as-synthesized material. The photocatalytic performance of p-n NiO-ZnO for photodegradation of crystal violet dye was significantly higher than pristine NiO and ZnO. The photocatalytic activities of NiO, ZnO and NiO-ZnO were found in the ratio of 1: 3.8: 7.8, respectively. Similarly, the ratio of photocatalytic activities of 5% NiO-ZnO, 10% NiO-ZnO, and 15% NiO-ZnO was 1: 1.2: 0.8, respectively. The degradation data was analyzed for kinetics analyses using the Langmuir-Hinshelwood mechanism.

Teaching Biology in an innovative way has always posed challenges due to its complex terminology and abstract concepts. This study explored the effects of reality pedagogy as an alternative instructional strategy on learner motivation and academic performance in learning biology at the ninth-grade level. To achieve this, a quasi-experimental research design was employed, including a pre-test/post-test assessment, biology learning motivation questionnaires, semistructured interviews, and classroom observations. Descriptive and inferential statistics were used to analyse the data. The findings of the study revealed that the implementation of reality pedagogy had a positive influence on learner motivation in learning biology. Additionally, a significant correlation was identified and observed between motivation levels and academic achievement in the subject. The implications of these findings, as well as recommendations, are also discussed in the study.

With the increasing demand for wastewater treatment and multidrug resistance among pathogens, it was necessary to develop an efficient catalyst with enhanced photocatalytic and antibacterial applications. The present study proposes a facile and green strategy for synthesizing zinc oxide (ZnO) decorated nickel (Ni) nanomaterials. The synthesized Ni/ZnO nanocomposite displays a high crystallinity and spherical morphology, which was systematically characterized by XRD, SEM, FT-IR, UV-visible spectroscopy, EDX, HRTEM, and XPS techniques. In addition, the bacteriological tests indicated that Ni/ZnO nanocomposite exhibits potent antibacterial activity against human pathogens, i.e., Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus), and Escherichia coli (E. coli). The inhibition zone observed in light and dark conditions for E. coli was 16 (±0.3) mm and 8 (±0.4) mm, respectively, which confirms the high efficacy of the nanocomposite in the presence of light compared to dark conditions. The detailed inhibition mechanism of said bacterium and damage were also studied through fluorescence spectroscopy and SEM analysis, respectively. Evaluation of antioxidant activity based on free radical scavenging activity revealed that the Ni/ZnO nanocomposite effectively scavenges DPPH. In the photocatalytic performance, the Ni/ZnO nanocomposite exhibited a remarkable degradation ability under the optimized condition, which was attributed to their controllable size, high surface area, and exceptional morphology. Good selectivity, high photodegradation, and antibacterial activities and satisfactory hemolytic behavior of the as-prepared nanocomposite make them able to become a potential candidate for superior biological performance and environmental remediation.

In this work, a manganese selenide/graphene oxide (MnSe/GO)-based composite was prepared for wet-chemical assisted method against organic dye; herein, methylene blue (MB) dye removal from the water was employed as a metal selenide-based photocatalyst. The synthesized MnSe/GO composite was systematically characterized by X-ray diffraction (XRD), Fourier transform electron microscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and UV-visible diffuse reflectance spectroscopy (UV-vis. DRS). The structural characteristic revealed the adequate synthesis of the sample with good crystallinity and purity of the obtained products. The morphological analysis indicates the formation of MnSe nanoflakes composed of tiny particles on their surface. At the same time, the GO nanosheets with high aggregation were formed, which may be due to the van der Waals forces. The bond interaction and compositional analysis studies confirmed and supported the structural findings with high purity. The optical analysis showed the bandgap energies of MnSe and their composites MnSe (1.7 eV), 7% GO-MnSe (2.42 eV), 14% GO-MnSe (2.6 eV), 21% GO-MnSe (3.02 eV), and 28% GO-MnSe (3.24 eV) respectively, which increase the bandgap energy after GO and MnSe recombination. Among different contents, the optimized 21% GO-MnSe composite displayed enhanced photocatalytic properties. For instance, a short time of 90 min was taken compared with other concentrations due to the narrow bandgap of MnSe and the highly conductive charge carrier’s support, making the process to remove MB from water faster. These results show that the selenide-based photocatalyst can be an attractive candidate for future advanced photocatalysis applications.

The main objective of this work is to recycle unwanted industrial waste in order to produce innovative nanocomposites with improved mechanical, tribological, and thermal properties for use in various industrial purposes. In this context, powder metallurgy (PM) technique was used to fabricate iron (Fe)/copper (Cu)/niobium carbide (NbC)/granite nanocomposites having outstanding mechanical, wear and thermal properties. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) examinations were used to investigate the particle size, crystal size, and phase composition of the milled samples. Additionally, it was investigated how different volume percentages of the NbC and granite affected the sintered specimens in terms of density, microstructure, mechanical and wear properties, and coefficient of thermal expansion (CTE). According to the findings, the milled powders included particles that were around 55 nm in size and clearly contained agglomerates. The results showed that the addition of 4 vol.% NbC and 8 vol.% granite nanoparticles caused a reduction in the Fe–Cu alloy matrix particle sizes up to 47.8 nm and served as a barrier to the migration of dislocations. In addition, the successive increase in the hybrid concentrations led to a significant decrease in the crystal size of the samples prepared as follows: 29.73, 27.58, 22.69, 19.95 and 15.8 nm. Furthermore, compared with the base Fe–Cu alloy, the nanocomposite having 12 vol.% of hybrid reinforcement demonstrated a significant improvement in the microhardness, ultimate strength, Young’s modulus, longitudinal modulus, shear modulus, bulk modulus, CTE and wear rate by 94.3, 96.4, 61.1, 78.2, 57.1, 73.6, 25.6 and 61.9%, respectively. This indicates that both NbC and granite can actually act as excellent reinforcements in the Fe alloy.

Implementation of Bhutan Professional Standards for Teachers in Bhutan is a key impetus for teachers across the country to enhance impeccable teacher competency. Studies on teachers' attitudes towards professional standards show a positive as there was a significant correlation between teachers' competencies, learners' academic achievement, and the quality of education. However, Bhutan Professional Standards for Teachers is relatively new and there is little study exists relative to Bhutan. The study on Teachers' Attitudes to the Implementation of Bhutan Professional Standards for Teachers in Bhutan aimed to explore and get a snapshot view of teachers on Bhutan Professional Standards for Teachers. Through a cross-sectional survey design, data were collected from 155 participants using the Five-Pointed Likert Scale and two open-ended questionnaires. The descriptive analysis revealed that teachers have fairly positive attitudes toward the implementation of Bhutan Professional Standards for Teachers. Associated challenges, the implication of the findings, and recommendations are also discussed.

Abstract Introduction Localized prostate cancer (PCa) is one of the most common malignancies in the United States. Despite continued refinement of robot assisted radical prostatectomy (RARP) surgical methods, post-surgical erectile dysfunction and urinary incontinence remain significant challenges due to iatrogenic injury of local nervous tissue. Thus, the development of therapeutic strategies, including the use of biologic adjuncts to protect and/or enhance recovery and function of nerves following RARP is of growing interest. Perinatal tissue allografts have been investigated as one such biologic adjunct to nerve sparing RARP. However, knowledge regarding their clinical efficacy in hastening return of potency and continence as well as the potential underpinning biological mechanisms involved remains understudied. Thus, the objective of this literature review was to summarize published basic science and clinical studies supporting and evaluating the use of perinatal allografts for nerve repair and their clinical efficacy as adjuncts to RARP, respectively. Methods The literature as of May 2024 was reviewed non-systematically using PubMed, EMBASE, Scopus, and Web of Science databases. The search terms utilized were “robotic prostatectomy”, “prostate cancer”, “nerve sparing”, “perinatal tissue”, “allograft”, “potency”, and “continence” alone or in combination. All articles were reviewed and judged for scientific merit by authors RP and JM, only peer-reviewed studies were considered. Results Eight studies of perinatal tissue allograph use in RARP were deemed worthy of inclusion in this nonsystematic review. Conclusions Incontinence and impotence remain significant comorbidities despite continued advancement in surgical technique. However, basic science research has demonstrated potential neurotrophic, anti-fibrotic, and anti-inflammatory properties of perinatal tissue allografts, and clinical studies have shown that patients who receive an intra-operative prostatic perinatal membrane wrap have faster return to potency and continence.

This study seeks to explore and understand the Bhutanese secondary school teacher's perception of increased Continuous Formative Assessment (CFA) weightings and the associated opportunities and challenges. Grounded on pragmatism, this study employed an explanatory sequential mixed methods design. The quantitative and qualitative data were collected through a survey of 370 randomly sampled secondary teachers and 16 participants for 4 FGDs. The descriptive statistics were conducted using Statistical Package for Social Science (SPSS) version 25 to determine the perception of teachers on new CFA weightings, opportunities of CFA, and challenges of CFA. The qualitative data were analyzed by coding and identifying emerging themes. The qualitative and quantitative data findings were triangulated. The result of this study revealed that teachers have a positive perception of the increased CFA weightings.

This qualitative study explored the potential sources of enjoyment and boredom in geography classes among Bhutanese secondary school students. Utilizing open-ended surveys and semi-structured interviews, 206 participants aged 17 to 22, predominantly from classes 11 and 12, shared their perspectives. The thematic analysis of the data revealed four sources that contributed to students' enjoyment and boredom in geography classes. The findings on sources of enjoyment included sources like enthusiasm, encouragement, friendliness and support which emerged as crucial contributors to enjoyment. Moreover, video-integrated lessons, field trips, and challenging and hands-on activities, actively contributed to positive emotional experiences. Additionally, individual interest in geography, aspirations to become geographers, the relevance of materials and topics to learners' interests, were found to enhance geography class enjoyment. Conversely, the findings on sources of boredom included monotonous teaching methods, poorly prepared lessons, difficult content, dissatisfaction with presentation tasks, textbook-based activities, lack of interest in the subject or negative moods linked to boredom. Altogether, this study contributes to the growing research trend, focusing on the dimensions of students' emotions in the learning process. Based on the findings of the study, recommendations are made and directions for future research are presented.

Climate change drives species distribution shifts, affecting the availability of resources people rely upon for food and livelihoods. These impacts are complex, manifest at local scales, and have diverse effects across multiple species. However, for wild capture fisheries, current understanding is dominated by predictions for individual species at coarse spatial scales. We show that species-specific responses to localized environmental changes will alter the collection of co-occurring species within established fishing footprints along the U.S. West Coast. We demonstrate that availability of the most economically valuable, primary target species is highly likely to decline coastwide in response to warming and reduced oxygen concentrations, while availability of the most abundant, secondary target species will potentially increase. A spatial reshuffling of primary and secondary target species suggests regionally heterogeneous opportunities for fishers to adapt by changing where or what they fish. Developing foresight into the collective responses of species at local scales will enable more effective and tangible adaptation pathways for fishing communities.

Science education and scientific literacy has gained enormous attention in the global educational scenario. In many cases, however, the holistic intent of science education is largely affected due to the lack of adequate understanding of the Nature of Science (NOS). This cross-sectional study was carried out to establish Bhutanese pre-service science teachers' conceptions of the NOS. One hundred and seven pre-service science teachers from one of the education colleges in Bhutan took part in the study based on convenient sampling design. The Myths of Science Questionnaire (MOSQ) adapted from Bauraphan (2009) was administered through online survey mode. The descriptive statistics in terms of frequency supported by written responses were employed to analyse the data. Findings showed that the Bhutanese pre-service science teachers do not possess matured and informed view of the NOS in many areas of scientific knowledge, scientific methods, scientists' practices, and scientific enterprise. Implications of the findings related to teacher preparation courses are discussed.