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Local people’s pro-tourism behavioural intention plays an important role in determining the sustainability and success of a tourism destination. A semi-structured questionnaire was randomly administered to residents aged 18 years and above of Botswana’s two premier tourism centres (Maun and Kasane). These two exotic tourism areas were chosen in this study to ensure enrichment of the literature through sharing of lived experiences and critical decision-making by people in the face of an impending disaster (i.e. COVID-19) threatening their existence. The Theory of Reasoned Action (TRA) was used to provide a better understanding in linking residents’ attitudes in supporting or opposing tourism development in the face of COVID-19. Overall, majority (67.5%, p = 0.015) of the respondents indicated that they are willing to accept some inconvenience as long as they benefit from tourism industry. Also, most (84.4% (p = 0.034)) residents indicated that they were willing to welcome tourists because of the contribution tourists bring to the economy of their area. Thus, a positive attitude towards tourism development and tourists from locals will likely lead to a more positive behaviour supporting tourism in host communities. The study recommends that, of utmost importance, key stakeholders in the tourism industry including policymakers and planners should devise and implement strategies geared towards positively influencing attitudes of local communities towards tourism development. The results from this study will assist government and other tourism stakeholders as they devise mitigating strategies to sustain and guide future tourism operations following socioeconomic devastations from COVID-19 pandemic.

In the present work, the influence of alkali ions (Li, Na, K) on the structural and spectroscopic properties of silica glasses doped with Sm3+ was investigated. Infrared and Raman spectroscopy techniques were used to investigate the structural properties of the alkali silicate glasses. The optical absorption showed bands characteristic of Sm3+ ions in alkali silicate glasses, and this was investigated. The Judd–Ofelt theory was applied to evaluate the phenomenological intensity parameters (Ω2, Ω4, and Ω6) of the optical absorption measurements. The multi-channel visible and near infrared emission transitions originating from the 4G5/2-emitting state of the Sm3+ in alkali silicate glasses with a maximum phonon energy of ~1050 cm−1 were investigated. From the evaluated Judd–Ofelt parameters, radiative parameters such as spontaneous emission probabilities, radiative lifetimes, branching ratios, and stimulated emission cross-sections were calculated. The recorded luminescence spectra regions revealed intense green, orange, red, and near-infrared emission bands, providing new traces for developing tunable laser and optoelectronic devices.

AbstractThis research uses a Classification and Regression Tree (CART) model with Google Earth Engine (GEE) to assess the winter season’s land cover and change detection mapping impact on the evapotranspiration (crop water requirement) parameters. Winter seasons, crucial for agricultural planning, and irrigation water requirement challenges in accurately mapping land cover and detecting changes due to the dynamic nature of farming practices during this period. In this study, Landsat-8 OLI images have been combined to map Land use and Land cover (LULC) and other change detection mapping in Akola Block, Maharashtra, India, during the 2018–2022 winter season. As an discoverer researcher that found detailed information of LULC classes during last 2018 to 2022 winter seasons, the use of the CART model in combination with a cloud-computing GEE demonstrates to be a practical approach for accurate land cover classification and change detection maps to create a pixel-based winter seasons information of study area. The novelty of this study lies in its innovative use of GEE, a powerful platform for remote sensing and geospatial analysis, to create LULC maps with remarkable accuracy. Achieving a 100% training accuracy across the four years under consideration is an exceptional feat, highlighting the reliability and stability of the methodology. Furthermore, the validation accuracy values, ranging from 89 to 94% for the winter seasons of 2018 to 2022, underscore the robustness of this approach. Such consistently high accuracy in mapping LULC over time is a groundbreaking achievement and offers a new dimension to the field of hydrology. For the hydrological community, the implications of this study are profound. Accurate LULC mapping and change detection provide critical data for modeling and analyzing the effects of land use changes on water resources, watershed management, and water quality. The User, Kappa, and Producer accuracy metrics used in this research highlight the model’s performance and its suitability for hydrological applications. These accurate LULC maps can aid in the development of hydrological models, forecasting, and decision-making processes, ultimately contributing to more effective water resource management and environmental conservation. In summary, this study’s innovative use of GEE, its remarkable accuracy in LULC mapping, and its relevance to the hydrological community demonstrate the potential for advanced remote sensing and geospatial tools to significantly improve our understanding of land use changes and their implications for water resources and environmental management.

The rapid emergence of resistant bacteria is occurring worldwide, endangering the efficacy of antibiotics. Hence, there is a need to search for new sources of antibiotics that either exhibit novel structures or express a new mechanism of action. The lichen Usnea, with its wide range of unique, biologically potent secondary metabolites, may solve this problem. In this study, Usnea species were collected in the Northern Philippines, identified through combined morphological and biochemical characterization, and tested for antimicrobial activities against the multidrug-resistant ESKAPE pathogens, i.e., Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter cloacae, two standard antibiotic-sensitive test bacteria, and a yeast. A total of 46 lichen specimens were collected and later identified as Usnea baileyi (10), U. diffracta (10), U. glabrata (12), U. longissima (4), and U. rubicunda (10). The results show that the crude extracts of the Usnea species exhibited promising in vitro inhibitory activities against standard antibiotic-sensitive (E. faecalis ATCC 29212) and multidrug-resistant (methicillin-resistant S. aureus and E. faecalis) Gram-positive bacteria. Additionally, lichen compounds of representative specimens per species were identified and profiled using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). The detection of lichen acids (LA) via HPLC showed the presence of 24 peaks of lichen acids. TLC-bioautography identified the bioactive lichen acids as alectronic acid, connorstictic acid, consalazinic acid, diffractaic acid, echinocarpic acid, erythrin acid, galbinic acid, hypoconstictic acid, hyposalazinic acid, hypostictic acid, lobaric acid, menegazzaic acid, micareic acid, pannarin, salazinic acid, stictic acid, and usnic acid. Our study highlighted the wide spectrum of opportunities for using lichens for the discovery of potential antimicrobial agents.

Campuses of Nigerian universities, especially the older ones, are home to aged trees that were originally planted for environmental beautification and aesthetics. However, due to the current global climate change and increased vulnerability to abiotic and biotic stressors, the old trees could pose threats to pedestrians, structures, and roads within the university campus environments. Therefore, the objective of this paper is to develop a geodatabase and evaluate the health risk assessment of avenue trees on selected roads in a tertiary institution in Ibadan, Oyo State, Nigeria using appropriate standard methods. Results obtained reported a total of 121 individual avenue trees belonging to 14 species along the study roads. The geospatial distribution analysis revealed that Emotan road had a lower density of avenue trees compared to Benue and Oduduwa roads. Furthermore, the health risk assessment indicated that 17.35% of the individual avenue trees had defects, posing potential hazards and risks of tree failure, and potential damage to pedestrians, vehicles, and neighboring utilities. The developed geodatabase is user-friendly and allows for easy data storage and quick information retrieval on the avenue trees, enhancing their maintenance and risk management. Furthermore, this study shows that systematic replacement, replanting, and management of avenue tree species could be a proactive initiative for the expansion of the geodatabase and to reduce negative health impacts. [ABSTRACT FROM AUTHOR]

Abstract Background Accessing COVID-19 vaccines is a challenge despite successful clinical trials. This burdens the COVID-19 treatment gap, thereby requiring accelerated discovery of anti-SARS-CoV-2 agents. This study explored the potential of anti-HIV reverse transcriptase (RT) phytochemicals as inhibitors of SARS-CoV-2 non-structural proteins (nsps) by targeting in silico key sites in the structures of SARS-CoV-2 nsps. One hundred four anti-HIV phytochemicals were subjected to molecular docking with nsp3, 5, 10, 12, 13, 15, and 16. Top compounds in complex with the nsps were investigated further through molecular dynamics. The drug-likeness and ADME (absorption, distribution, metabolism, and excretion) properties of the top compounds were also predicted using SwissADME. Their toxicity was likewise determined using OSIRIS Property Explorer. Results Among the top-scoring compounds, the polyphenolic functionalized natural products comprised of biflavones 1, 4, 11, 13, 14, 15; ellagitannin 9; and bisisoquinoline alkaloid 19 were multi-targeting and exhibited strongest binding affinities to at least two nsps (binding energy = − 7.7 to − 10.8 kcal/mol). The top ligands were stable in complex with their target nsps as determined by molecular dynamics. Several top-binding compounds were computationally druggable, showed good gastrointestinal absorptive property, and were also predicted to be non-toxic. Conclusions Twenty anti-HIV RT phytochemicals showed multi-targeting inhibitory potential against SARS-CoV-2 non-structural proteins 3, 5, 10, 12, 13, 15, and 16. Our results highlight the importance of polyhydroxylated aromatic substructures for effective attachment in the binding/catalytic sites of nsps involved in post-translational mechanism pathways. As such with the nsps playing vital roles in viral pathogenesis, our findings provide inspiration for the design and discovery of novel anti-COVID-19 drug prototypes.