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Laccases from white-rot fungi catalyze lignin depolymerization, a critical first step to upgrading lignin to valuable biodiesel fuels and chemicals. In this study, a wildtype laccase from the basidiomycete Fomitiporia mediterranea (Fom_lac) and a variant engineered to have a carbohydrate-binding module (Fom_CBM) were studied for their ability to catalyze cleavage of β-O-4 ether and C-C bonds in phenolic and non-phenolic lignin dimers using a nanostructure-initiator mass spectrometry-based assay. Fom_lac and Fom_CBM catalyze β-O-4 ether and C-C bond breaking, with higher activity under acidic conditions (pH < 6). The potential of Fom_lac and Fom_CBM to enhance saccharification yields from untreated and ionic liquid pretreated pine was also investigated. Adding Fom_CBM to mixtures of cellulases and hemicellulases improved sugar yields by 140% on untreated pine and 32% on cholinium lysinate pretreated pine when compared to the inclusion of Fom_lac to the same mixtures. Adding either Fom_lac or Fom_CBM to mixtures of cellulases and hemicellulases effectively accelerates enzymatic hydrolysis, demonstrating its potential applications for lignocellulose valorization. We postulate that additional increases in sugar yields for the Fom_CBM enzyme mixtures were due to Fom_CBM being brought more proximal to lignin through binding to either cellulose or lignin itself.

Objective: To document the pattern of particulate matter 2.5 (PM2.5) concentration in urban and suburban schools in Ho Chi Minh City (HCMC) and to estimate the prevalence of wheezing and rhinitis among schoolchildren according to sociodemographic characteristics and school-related conditions. Material and Methods: A cross-sectional study was conducted in two suburban and two urban schools in HCMC. PM2.5 concentrations were monitored hourly from August to December in 2022. Children aged 9-13 years (N=1,033) provided data on wheezing and rhinitis symptoms in the previous year. The daily levels of PM2.5 were monitored in each school. Respiratory symptoms were compared between areas and across school-related conditions. Results: Geometric means of the daily PM2.5 concentration in the suburban and urban areas were 61.2 μg/m3 and 31.0 μg/m3, respectively (p-value

OBJECTIVES Depression in medical students is concerning, potentially fueled by many stressors including career choice-relating stress. Choosing Medicine is a life-long commitment, and low intrinsic motivation or excessive dependence on family can complicate this decision and adding stress throughout their training. This stress intensifies in the final year, as students lacking personal drive struggle to see themselves continuing the career. Given limited studies on this crucial topic in Asia and Vietnam, we explored direct linkage between career choice motivation and depression in final-year medical students. METHODS A cross-sectional study was conducted with 569 final-year students between June and July 2020. The Vietnamese Patient Health Questionnaire 9 (PHQ-9) and 16-item CCM questionnaire were used as survey tools. Univariate analysis was used for descriptive statistics (absolute and relative frequency, mean (M), standard deviation (SD). Multinomial logistic regression models were used to explore the relationship between variables using STATA 5.1. RESULTS The depression among participants was about 24.6% (PHQ-9 cut-off ≥ 12). No difference in gender was found regarding depression. The most acknowledged motivator is securing employment (M = 4.14, SD = 1.02) and the least is parental wishes (M = 3.17, SD = 1.32). Familial influence on career choice significantly increased odds of having “ moderately-severe depression ” (OR = 1.17, 95% CI 1.04-1.32) and “ severe depression ” (OR = 1.36, 95% CI 1.10-1.68), whereas, career-choice motivators including satisfaction (OR = .76, 95% CI .60-.97), self-competence (OR = .80, 95% CI .66-.97) and career success (OR = .84, 95% CI .71-.99) were found to be protective factors for depression. CONCLUSIONS Roughly a quarter of final-year medical students encountered depression. Occupational security ranked as the primary motivator, with parental wish being the least. Familial influence heightened depression risk, while career prospects, satisfaction and self-efficacy acted as protective factors. Medical career paths should align with intrinsic motivations and personal interests for better mental health outcomes.

Background: Previous studies have shown that the Gaming Disorder Test (GDT) and Gaming Disorder Scale for Adolescents (GADIS-A) have promising validity and reliability when assessing symptoms of gaming disorder among young adults. However, validity and reliability properties of the two scales have not been established among a Vietnamese population. Objective: The present study translated the GDT and GADIS-A into Vietnamese and examined their factor structures, measurement invariance, convergent validity, concurrent validity, and divergent validity among university students. Methods: A total of 610 young adults (mean age = 21.09 years; 63.4% females) were recruited using convenience sampling and who completed a paper-and-pencil survey between April and June 2023. All participants completed a demographic questionnaire, GDT, GADIS-A, and six standardized scales related to gaming disorder, social media addiction, smartphone addiction, and psychological distress. Confirmatory factor analysis (CFA), internal consistency testing, and Pearson's correlations were performed. Results: CFA showed that the GDT had a one-factor structure and the GADIS-A had a two-factor structure. The internal consistency was excellent for both scales among this population. Moreover, both GDT and GADIS-A showed convergent, concurrent, and divergent validity with other standardized scales. Conclusion: The Vietnamese versions of the GDT and GADIS-A have good psychometrics, which may be utilized in future research regarding gaming disorder among Vietnamese populations. [ABSTRACT FROM AUTHOR]

This integrated computational and experimental study comprehensively examines the viability of competing inner‐sphere electron transfer (ISET) and outer‐sphere electron transfer (OSET) processes in [Cu(dap)2]+‐mediated atom‐transfer radical additions (ATRA) of olefins and CF3SO2Cl that can deliver both R−SO2Cl and R−Cl products. Five sterically‐ and electronically‐varied representative alkenes were selected from which to explore and reconcile a range of experimentally observed outcomes. Findings are consistent with photoexcited [Cu(dap)2]+ initiating photoelectron transfer via ISET and the subsequent regeneration of the oxidized catalyst via ISET in the ground state to close the catalytic cycle and liberate products. R−SO2Cl/R−Cl product ratios appear to be primarily governed by the relative rates of direct catalyst regeneration {i.e., [Cu(dap)2SO2Cl]⋅++R⋅} and ligand exchange {i.e., [Cu(dap)2SO2Cl]⋅++Cl− }. Through this work, a more consistent and more complete conceptual framework has been developed to better understand this chemistry and how catalyst regeneration occurs. It is this important ground state process, which closes the catalytic cycle, and ultimately controls the enantioselectivity of ATRA reactions employing chiral copper photocatalysts. [ABSTRACT FROM AUTHOR]

Two dimensional (2D) nanosheets of MoS2 were succesfully produced by an exfoliation process in aqueous media with the support from peptides and sonication. The exfoliation process assisted by uncapped MoSBP1 peptides was found to have enhanced efficiency in comparison to the capped counterpart. MoS2 nanosheets obtained using uncapped MoSBP1 have thinner structures containing one layer of MoS2, while in capped version of peptides, MoS2 nanosheets tend to form multilayer (up to 4) structures of exfoliated sheets. Molecular dynamics simulations indicate that inter-sheet gaps generated by sonication in MoS2 nanostacks cannot be maintained by water only; the gaps closed after ∼11 ns. Both capped CMoSBP1 and uncapped MoSBP1 were seen to spontaneously insert into the gap in nanostacks of MoS2 and they can ultimately maintain the inter-sheet gap for longer (≥20 ns). Potential of mean force profiles for the association of two MoS2 nanosheets decorated with CMoSBP1 and MoSBP1 versions of peptides revealed that uncapped MoSBP1 peptides provide good protection from MoS2 nanosheet re-unification. Such protection can prevent the nanosheets from reassociation and subsequent aggregation, whereas the capped CMoSBP1 peptides can offer protection, but over a shorter range. These simulation results could explain the experimental observation of greater efficiency of exfoliation in uncapped MoSBP1 peptides. [ABSTRACT FROM AUTHOR]

Two epimeric pairs of N‐Ts‐protected cyclohexylamines that incorporate an unsaturated side‐chain at the C2 position have been prepared. Contrary to expectations, none of these underwent clean, photochemically‐induced intramolecular hydroamination reactions to give the corresponding perhydro‐indole or ‐quinoline. However, they did participate in efficient olefin cross metathesis (OCM) reactions with methyl crotonate. Three of the four acrylates so‐formed engaged in base‐promoted and completely diastereoselective, intramolecular aza‐Michael addition (cyclization) reactions to give the isomeric and C2‐substituted perhydro‐indoles or ‐quinolines with the structures of these being confirmed by single‐crystal X‐ray analyses. DFT calculations generated results consistent with the observed diastereoselectivities and the proposed transition states. Manipulation of the ester groups associated with the cyclization products allowed for their conversion, inter alia, into the corresponding n‐propyl residues and thus providing novel analogues of neurotoxic alkaloids such as pumiliotoxin C. [ABSTRACT FROM AUTHOR]

Cordyceps militaris is widely used in many Asian countries as a traditional medicinal material for treating various ailments. This study aims to investigate how the growth of the medicinal mushroom C. militaris is influenced by the culture medium and culture conditions in a controlled laboratory setting. The results indicate that aromatic brown rice (BT7) significantly increases the fresh weight of all three collected materials of C. militaris. Shoot length and body weight were promoted by the glucose content, silkworm pupa powder and pH of the culture medium ranging from 6.0 to 7.0, with the optimal glucose content being 30.0g per bottle. The optimal temperature for growth is between 22°C and below 25°C, with a light intensity of 600-700 lux. For higher cordycepin content, the recommended harvesting time is 65 days, while for adenosine content should be 55 days after inoculation. These findings provide valuable information to improve both the biomass and quality of C. militaris, which is crucial for large-scale production in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Alzheimer's disease (AD), the most prevalent neurodegenerative disorder globally, has emerged as a significant health concern. Recently it has been revealed that extracellular vesicles (EVs) play a critical role in AD pathogenesis and progression. Their stability and presence in various biofluids, such as blood, offer a minimally invasive window for monitoring AD‐related changes. METHODS: We analyzed plasma EV‐derived messenger RNA (mRNA) from 82 human subjects, including individuals with AD, mild cognitive impairment (MCI), and healthy controls. With next‐generation sequencing, we profiled differentially expressed genes (DEGs), identifying those associated with AD. RESULTS: Based on DEGs identified in both the MCI and AD groups, a diagnostic model was established based on machine learning, demonstrating an average diagnostic accuracy of over 98% and showed a strong correlation with different AD stages. DISCUSSION: mRNA derived from plasma EVs shows significant promise as a non‐invasive biomarker for the early detection and continuous monitoring of AD. Highlights: The study conducted next‐generation sequencing (NGS) of mRNA derived from human plasma extracellular vesicles (EVs) to assess Alzheimer's disease (AD).Profiling of plasma EV‐derived mRNA shows a significantly enriched AD pathway, indicating its potential for AD‐related studies.The AD‐prediction model achieved a receiver‐operating characteristic area under the curve (ROC‐AUC) of more than 0.98, with strong correlation to the established Clinical Dementia Rating (CDR). [ABSTRACT FROM AUTHOR]

The increasing integration of distributed energy resources such as photovoltaic (PV) systems into distribution networks introduces intermittent and variable power, leading to high voltage fluctuations. High PV integration can also result in increased terminal voltage of the network during periods of high PV generation and low load consumption. These problems can be solved by optimal utilization of the reactive power capability of a smart inverter. However, solving the optimization problem using a detailed mathematical model of the distribution network may be time-consuming. Due to this, the optimization process may not be fast enough to incorporate this rapid fluctuation when implemented in real-time optimization. To address these issues, this paper proposes a co-simulation-based optimization approach for optimal reactive power control in smart inverters. By utilizing co-simulation, the need for detailed mathematical modeling of the power flow equation of the distribution network in the optimization model is eliminated, thereby enabling faster optimization. This paper compares three optimization algorithms (improved harmony search, simplicial homology global optimization, and differential evolution) using models developed in OpenDSS and DigSilent PowerFactory. The results demonstrate the suitability of the proposed co-simulation-based optimization for obtaining optimal setpoints for reactive power control, minimizing total power loss in distribution networks with high PV integration. This research paper contributes to efficient and practical solutions for modeling optimal control problems in future distribution networks. [ABSTRACT FROM AUTHOR]

Virtual reality is providing new opportunities for health and well-being, organizational learning, and tourism management. The study reported in this paper aims to examine whether engaging in a virtual reality tourism experience could function as a restorative intervention strategy to enhance mental well-being of employees in the workplace. The study employed a lab-based pre–post experimental design to test the effectiveness of a virtual reality tourism experience, involving a nature-based marine setting, to enhance mental restoration and reduce mental fatigue. The results show that 3 minutes of a virtual tourism experience can lead to enhanced concentration while boosting the mental well-being of employees, while, at the same time, providing destinations with an opportunity to promote "real" experiences. [ABSTRACT FROM AUTHOR]

Landslides lead to widespread devastation and significant loss of life in mountainous regions around the world. Susceptibility assessments can provide critical data to help decision‐makers, for example, local authorities and other organizations, mitigating the landslide risk, although the accuracy of existing studies needs to be improved. This study aims to assess landslide susceptibility in the Thua Thien Hue province of Vietnam using deep neural networks (DNNs) and swarm‐based optimization algorithms, namely Adam, stochastic gradient descent (SGD), Artificial Rabbits Optimization (ARO), Tuna Swarm Optimization (TSO), Sand Cat Swarm Optimization (SCSO), Honey Badger Algorithm (HBA), Marine Predators Algorithm (MPA) and Particle Swarm Optimization (PSO). The locations of 945 landslides occurring between 2012 and 2022, along with 14 conditioning factors, were used as input data to build the DNN and DNN‐hybrid models. The performance of the proposed models was evaluated using the statistical indices receiver operating characteristic curve, area under the curve (AUC), root mean square error, mean absolute error (MAE), R2 and accuracy. All proposed models had a high accuracy of prediction. The DNN‐MPA model had the highest AUC value (0.95), followed by DNN‐HBA (0.95), DNN‐ARO (0.95), DNN‐Adam (0.95), DNN‐SGD (0.95), DNN‐TSO (0.93), DNN‐PSO (0.9) and finally DNN‐SCSO (0.83). High‐precision models have identified that the majority of the western region of Thua Thien Hue province is very highly susceptible to landslides. Models like the aforementioned ones can support decision‐makers in updating large‐scale sustainable land‐use strategies. [ABSTRACT FROM AUTHOR]