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Photothermal catalytic CO2 hydrogenation is a prospective strategy to simultaneously reduce CO2 emission and generate value-added fuels. However, the demand of extremely intense light hinders its development in practical applications. Herein, this work reports the novel design of Ni-based selective metamaterial absorber and employs it as the photothermal catalyst for CO2 hydrogenation. The selective absorption property reduces the heat loss caused by radiation while possessing effectively solar absorption, thus substantially increasing local photothermal temperature. Notably, the enhancement of local electric field by plasmon resonance promotes the adsorption and activation of reactants. Moreover, benefiting from the ingenious morphology that Ni nanoparticles (NPs) are encapsulated by SiO2 matrix through co-sputtering, the greatly improved dispersion of Ni NPs enables enhancing the contact with reaction gas and preventing the agglomeration. Consequently, the catalyst exhibits an unprecedented CO2 conversion rate of 516.9 mmol gcat -1 h-1 under 0.8 W cm-2 irradiation, with near 90% CO selectivity and high stability. Significantly, this designed photothermal catalyst demonstrates the great potential in practical applications under sunlight. This work provides new sights for designing high-performance photothermal catalysts by thermal management.
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Background and objective: Acute kidney injury (AKI) affects up to 20% of hospitalizations and is associated with chronic kidney disease, cardiovascular disease, increased mortality, and increased health care costs. Proper documentation of AKI in discharge summaries is critical for optimal monitoring and treatment of these patients once discharged. Currently, there is limited literature evaluating the quality of discharge communication after AKI. This study aimed to evaluate the accuracy and quality of documentation of episodes of AKI at a tertiary care center in British Columbia, Canada. Methods design setting patients and measurements: This was a retrospective chart review study of adult patients who experienced AKI during hospital admission between January 1, 2018, and December 31, 2018. Laboratory data were used to identify all admissions to the cardiac and general medicine ward complicated by AKI defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria. A random sample of 300 AKI admissions stratified by AKI severity (eg, stages 1, 2, and 3) were identified for chart review. Patients were excluded if they required ongoing renal replacement therapy after admission, had a history of kidney transplant, died during their admission, or did not have a discharge summary available. Discharge summaries were reviewed for documentation of the following: presence of AKI, severity of AKI, AKI status at discharge, practitioner and laboratory follow-up plans, and medication changes. Results: A total of 1076 patients with 1237 AKI admissions were identified. Of the 300 patients selected for discharge summary review, 38 met exclusion criteria. In addition, AKI was documented in 140 (53%) discharge summaries and was more likely to be documented in more severe AKI: stage 1, 38%; stage 2, 51%; and stage 3, 75%. Of those with their AKI documented, 94 (67%) documented AKI severity, and 116 (83%) mentioned the AKI status or trajectory at the time of discharge. A total of 239 (91%) of discharge summaries mentioned a follow-up plan with a practitioner, but only 23 (10%) had documented follow-up with nephrology. Patients with their AKI documented were more likely to have nephrology follow-up than those without AKI documented (17% vs 1%). Regarding laboratory investigations, 92 (35%) of the summaries had documented recommendations. In summaries that included medications typically held during AKI, only about half made specific reference to those medications being held, adjusted, or documented a post-discharge plan for that medication. For those with nonsteroidal anti-inflammatory drugs (NSAIDs) listing, 64% of discharge summaries mentioned holding, and 9% mentioned a discharge plan. For those with angiotensin converting enzyme inhibitor (ACEi)/angiotensin II receptor blocker (ARB) listing, 38% mentioned holding these medications, and 46% mentioned a discharge plan. In summaries with diuretics listed, 35% mentioned holding, and 51% included a discharge plan. Conclusions and limitations: We found suboptimal quality and completeness of discharge reporting in patients hospitalized with AKI. This may contribute to inadequate follow-up and post-hospitalization care for this patient population. Strategies are required for increasing the presence and quality of AKI reporting in discharge summaries. Limitations include our definition of AKI based on lab criteria, which may have missed some of the injuries that met the criteria based on urine output. Another limitation is that our definition of AKI based on the highest and lowest creatinine during admission may have led to some overclassification. In addition, without outpatient laboratories, it is possible that we have not captured the true baseline creatinine in some patients.
Contexte et objectif: L'insuffisance rénale aiguë (IRA) complique jusqu'à 20 % des hospitalisations; elle est associée à l'insuffisance rénale chronique, aux maladies cardiovasculaires, à une mortalité accrue et à une augmentation des coûts de santé. La documentation appropriée de l'IRA dans les résumés de départ est essentielle pour optimiser la surveillance et le traitement des patients après leur sortie de l'hôpital. Il existe peu de littérature évaluant la qualité de la documentation de l'IRA dans les résumés de départ. Cette étude visait à évaluer l'exactitude et la qualité de la documentation des épisodes d'IRA dans un center de soins tertiaires de la Colombie-Britannique (Canada). Méthodologie conception et cadre de l'étude sujets et mesures: Il s'agit d'une étude rétrospective des dossiers de patients adultes ayant présenté une IRA au cours de leur admission à l'hôpital entre le 1er janvier 2018 et le 31 décembre 2018. Les données de laboratoire ont été utilisées pour répertorier toutes les admissions compliquées par une IRA (définie par les critères KDIGO) dans les services de cardiologie et de médecine générale. Un échantillon aléatoire de 300 admissions avec IRA stratifiée selon sa gravité (p. ex., stade, 1, 2 et 3) a été constitué pour l'examen des dossiers. Ont été exclus les patients qui avaient eu besoin d'une thérapie de suppléance rénale continue après leur admission, ceux qui avaient des antécédents de transplantation rénale, ceux qui étaient décédés pendant leur admission et ceux pour qui aucun résumé de départ n'était disponible. Les résumés de départ ont été examinés à la recherche d'une mention des éléments suivants : présence d'une IRA, gravité de l'IRA, statut de l'IRA à la sortie, plans de suivi pour les tests de laboratoire et suivi avec un praticien, changements dans la médication. Résultats: En tout, 1 076 patients avec un total de 1 237 admissions avec IRA ont été identifiés. Parmi les 300 patients sélectionnés pour l'examen du résumé de départ, 38 répondaient aux critères d'exclusion. L'IRA avait été documentée dans 140 (53 %) des cas et plus elle était grave, plus elle était susceptible d'être documentée (stade 1 = 38 %; stade 2 = 51 %; stade 3 = 75 %). Parmi ceux où l'IRA était documentée, 94 (67 %) mentionnaient sa gravité et 116 (83 %) mentionnaient son statut ou sa trajectoire à la sortie du patient. Un plan de suivi avec le praticien était mentionné dans 239 (91 %) des résumés de départ, mais seuls 23 (10 %) mentionnaient un suivi en néphrologie. Les patients dont l'IRA était documentée étaient plus susceptibles de faire l'objet d'un suivi en néphrologie que ceux sans mention de l'IRA (17 % contre 1 %). En ce qui concerne les plans de suivi de laboratoire, 92 (35 %) des résumés contenaient des recommandations. Dans les résumés qui mentionnaient des médicaments normalement maintenus pendant un épisode d'IRA, seule la moitié environ faisait spécifiquement référence à ces médicaments comme ayant été cessés, ajustés ou documentés dans un plan post-sortie. Dans les résumés de départ qui listaient des AINS, 64 % mentionnaient qu'ils avaient été cessés temporairement et 9 % comprenaient un plan au congé de l'hôpital. Dans les résumés de départ qui listaient des IECA/ARA, 38 % mentionnaient que ces médicaments avaient été cessés temporairement et 46 % comprenaient un plan au congé de l'hôpital. Dans les résumés qui listaient des diurétiques, 35 % mentionnaient qu'ils avaient été cessés temporairement et 51 % comprenaient un plan au congé de l'hôpital. Limites et conclusion: Nous avons constaté que la qualité et l'exhaustivité des résumés de départ étaient sous-optimales chez les patients hospitalisés ayant vécu un épisode d'IRA. Cette situation peut contribuer à l'inadéquation du suivi et des soins post-hospitalization pour cette population de patients. Des stratégies sont nécessaires pour accroître la documentation d'un épisode d'IRA dans les résumés de départ et augmenter la qualité de sa communication. Les résultats de cette étude sont notamment limités par notre définition de l'IRA fondée sur des critères de laboratoire qui pourraient avoir manqué des patients répondant aux critères fondés sur la production d'urine. Notre définition de l'IRA fondée sur le taux de créatinine le plus élevée et le plus faible pendant l'admission pourrait également avoir conduit à un surdiagnostic. En outre, sans les résultats de laboratoires externes, il est possible que nous n'ayons pas saisi la mesure initiale réelle de la créatinine chez certains patients.
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Photocatalytic oxidative coupling of methane (OCM) into value-added industrial chemicals offers an appealing green technique for achieving sustainable development, whereas it encounters double bottlenecks in relatively low methane conversion rate and severe overoxidation. Herein, we engineer a continuous gas flow system to achieve efficient photocatalytic OCM while suppressing overoxidation by synergizing the moderate active oxygen species, surface plasmon-mediated polarization, and multipoint gas intake flow reactor. Particularly, a remarkable CH4 conversion rate of 218.2 µmol h-1 with an excellent selectivity of â¼90% toward C2+ hydrocarbons and a remarkable stability over 240 h is achieved over a designed Au/TiO2 photocatalyst in our continuous gas flow system with a homemade three-dimensional (3D) printed flow reactor. This work provides an informative concept to engineer a high-performance flow system for photocatalytic OCM by synergizing the design of the reactor and photocatalyst to synchronously regulate the mass transfer, activation of reactants, and inhibition of overoxidation.
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Unmanned aerial vehicles (UAVs) have been employed extensively for remote-sensing missions. However, due to their energy limitations, UAVs have a restricted flight operating time and spatial coverage, which makes remote sensing over huge regions that are out of UAV flight endurance and range challenging. PAD is an autonomous wireless charging station that might significantly increase the flying time of UAVs by recharging them in the air. In this work, we introduce PADs to simplify UAV-based remote sensing over a huge region, and then we explore the UAV route planning problem once PADs have been predeployed throughout a huge remote sensing region. A route planning scheme, named PAD-based remote sensing (PBRS), is proposed to solve the problem. The PBRS scheme first plans the UAV's round-trip routes based on the location of the PADs and divides the whole target region into multiple PAD-based subregions. Between adjacent subregions, the UAV flight subroute is planned by determining piggyback points to minimize the total time for remote sensing. We demonstrate the effectiveness of the proposed scheme by conducting several sets of simulation experiments based on the digital orthophoto model of Hutou Village in Beibei District, Chongqing, China. The results show that the PBRS scheme can achieve excellent performance in three metrics of remote sensing duration, the number of trips to charging stations, and the data-storage rate in UAV remote-sensing missions over huge regions with predeployed PADs through effective planning of UAVs.
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OBJECTIVES: To evaluate the effect of different exercise interventions on depressive symptoms in children and adolescents. METHODS: Randomized controlled trials (RCT) published until May 2023 were screened in four databases. The Cochrane collaboration tool was used to assess the risk of bias for quality evaluation. Stata 16.0 software was used for both a pairwise meta-analysis and a series of frequentist network meta-analyses (NMA). RESULTS: A total of 35 RCTs and 5393 participants were included. Aerobic exercise had the most significant effect on depressive symptoms (66.2%), followed by group training (62.5%), resistance exercise (59.0%), and aerobic combined with resistance exercise (57.9%). Furthermore, children and adolescents younger than 15 years showed significant improvement in depressive symptoms (SMD=-0.41, 95% CI (-0.63, -0.19), P < 0.01). The study also found a significant improvement in depression among healthy, obesity, and depressed populations (SMD=-0.25, 95% CI (-0.41, -0.08), P < 0.01); SMD=-0.15, 95% CI (-0.31, -0.00), P < 0.01; SMD=-0.75, 95% CI (-1.32, -0.19), P < 0.01). Additionally, 30 min of exercise had a significant effect (SMD=-0.14, 95% CI (-0,81, -0.01), P < 0.01), and 40-50 min of exercise had the best effect (SMD=-0.17, 95% CI (-0,33, -0.02), P < 0.01). Lastly, exercise frequency of three times per week was significant in children and adolescents (SMD=-0.42, 95% CI (-0,66, -0.18), P < 0.01). CONCLUSION: Exercise significantly improves depressive symptoms in children and adolescents, with aerobic exercise having the most significant effect. A 12-week, three-times-a-week, 40-50-minute exercise intervention was found to be more effective in younger children and adolescents.
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Depressão , Exercício Físico , Humanos , Criança , Adolescente , Metanálise em Rede , Depressão/prevenção & controle , Serviços de Saúde , Terapia por ExercícioRESUMO
Background: Upper-limb poststroke spasticity (PSS) negatively impacts on patients' quality of life. An increasing number of clinical trials have indicated that wet cupping with rehabilitation training is conductive to alleviate spastic muscle tone, thereby to improve upper-limb function. However, related evidence base is insufficient. This study systematically investigates the efficacy and safety of wet cupping with rehabilitation training on stroke patients with upper-limb spasticity. Methods: Eight separate databases and two clinical trial registries were searched from their inception to December 6, 2022. Two reviewers extracted the data and assessed the quality of the literature, independently. The mean difference (MD) or risk ratio (RR) were used as measure of effect size in meta-analysis. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used for the certainty of evidence. Results: Eight randomized controlled trials (RCTs) were quantified for meta-analysis. The results indicated that in comparison with the control group, wet cupping with rehabilitation training was more effective in reducing modified Ashworth scale score (MD = -0.60, 95% CI: -0.74, -0.46; P < 0.00001) and the integral electromyography value of biceps muscle (MD = -4.71, 95% CI: -6.74, -2.67; P < 0.00001), but improving effective rate (RR = 1.28, 95% CI: 1.15, 1.41; P < 0.00001), Fugl-Myer Assessment score (MD = 4.84, 95% CI: 3.05, 6.64; P < 0.00001) as well as Barthel Index score (MD = 6.38, 95% CI: 2.20, 10.57; P = 0.003). However, no significant difference was found regarding the integral electromyography value of triceps muscle between groups (MD = 1.72, 95% CI: -2.05, 5.48; P = 0.37). Conclusion: Wet cupping with rehabilitation training should be included in a comprehensive therapeutic regimen for stroke patients with upper-limb spasticity. However, these results need to be further verified by more RCTs with rigorous design and large sample size.
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OBJECTIVES: To evaluate the effect of different exercise interventions on depressive symptoms in children and adolescents. METHODS: Randomized controlled trials (RCT) published until May 2023 were screened in four databases. The Cochrane collaboration tool was used to assess the risk of bias for quality evaluation. Stata 16.0 software was used for both a pairwise meta-analysis and a series of frequentist network meta-analyses (NMA). RESULTS: A total of 35 RCTs and 5393 participants were included. Aerobic exercise had the most significant effect on depressive symptoms (66.2â¯%), followed by group training (62.5â¯%), resistance exercise (59.0â¯%), and aerobic combined with resistance exercise (57.9â¯%). Furthermore, children and adolescents younger than 15â¯years showed significant improvement in depressive symptoms (SMDâ¯=â¯-0.41, 95â¯% CI (-0.63, -0.19), Pâ¯<â¯0.01). The study also found a significant improvement in depression among healthy, obesity, and depressed populations (SMDâ¯=â¯-0.25, 95â¯% CI (-0.41, -0.08), Pâ¯<â¯0.01); SMDâ¯=â¯-0.15, 95â¯% CI (-0.31, -0.00), Pâ¯<â¯0.01; SMDâ¯=â¯-0.75, 95â¯% CI (-1.32, -0.19), Pâ¯<â¯0.01). Additionally, 30â¯min of exercise had a significant effect (SMDâ¯=â¯-0.14, 95â¯% CI (-0,81, -0.01), Pâ¯<â¯0.01), and 40-50â¯min of exercise had the best effect (SMDâ¯=â¯-0.17, 95â¯% CI (-0,33, -0.02), Pâ¯<â¯0.01). Lastly, exercise frequency of three times per week was significant in children and adolescents (SMDâ¯=â¯-0.42, 95â¯% CI (-0,66, -0.18), Pâ¯<â¯0.01). CONCLUSION: Exercise significantly improves depressive symptoms in children and adolescents, with aerobic exercise having the most significant effect. A 12-week, three-times-a-week, 40-50-min exercise intervention was found to be more effective in younger children and adolescents.
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BACKGROUND: Anxiety, depression, and stress are the most common mental health problems in childhood. Exercise interventions in childhood help to promote mental health. OBJECTIVE: To investigate the relationship between exercise interventions and improvement of negative emotions such as anxiety, depression, and stress in children (5-12 years). METHODS: Articles were searched in five electronic databases from their inception to January 2023. The meta-analysis was performed using Stata 16.0. RESULTS: Twenty-three intervention studies included 6830 children. 1) The exercise intervention group was significantly better than the control group in improving negative emotions (Standard Mean Difference SMD=-0.25, 95% Confidence Intervals CI: -0.34 to -0.15, P < 0.01). Exercise intervention improved different kinds of negative emotions: anxiety (SMD=-0.19, 95% CI: -0.33 to -0.06, P < 0.01), depression (SMD=-0.22, 95% CI: -0.43 to -0.01, P < 0.01), and stress (SMD=-0.33, 95% CI: -0.53 to -0.14, P < 0.01); it was most effective at relieving problematic stress. Exercise interventions lasting 20-45 min were most effective in improving children's negative emotions (SMD=-0.38, 95% CI: -0.56 to -0.20, P < 0.01). An exercise intervention period of 10 weeks was more effective in improving children's negative mood (SMD=-0.26, 95% CI: -0.34 to -0.17, P = 0.274). CONCLUSION: Exercise interventions may improve negative emotions such as anxiety, depression, and stress in children. These findings may have clinical implications for children with negative affect. However, these studies showed a large heterogeneity, and the results should be interpreted with caution. Future studies should report the variability of exercise interventions by gender, age group, and type, intensity, and place of exercise.
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Ansiedade , Exercício Físico , Criança , Humanos , Ansiedade/prevenção & controle , Bases de Dados Factuais , Terapia por Exercício , Saúde Mental , Pré-EscolarRESUMO
Physical activity habits are crucial for the physical and mental wellbeing of adolescents (individuals aged 10-19 years). However, few studies over the last two decades have systematically aggregated the influential factors of physical activity habits for adolescents. Five online databases (EBSCOhost (Eric), Psychology and Behavioral Sciences Collection, PubMed, Scopus, Web of Science) were searched for relevant studies published before 14 August 2022. Our systematic review indicated the following: 1) boys performed more physical activity habits than girls, whereas girls preferred to engage in moderate-to-vigorous physical activity; 2) physical activity in adolescents decreased with age; 3) African American adolescents performed significantly more habitual physical activities than white adolescents; 4) adolescents with higher literacy had better physical activity habits; 5) support from parents, teachers, friends, and others helped adolescents in developing physical activity habits; 6) adolescents who spent less time participating in habitual physical activity had a higher body mass index; 7) adolescents who reported higher levels of self-efficacy and satisfaction with school sports tended to have stronger physical activity habits; 8) sedentary behavior, smoking, drinking, prolonged screen time, negative emotions, and excessive use of media technology were correlated with reduced habitual physical activity in adolescents. These findings could help develop interventions to motivate adolescents and promote physical activity habits among them.
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BACKGROUND: Positive emotions help children and adolescents develop good personalities and interpersonal relationships. Evidence shows that participation in physical activity is associated with positive emotions in young people. However, there is still a lack of studies on the effects of physical activity on positive emotions in children and adolescents. OBJECTIVE: The purpose of this systematic review and meta-analysis was to examine the effects of physical activity on positive emotions in children and adolescents. METHODS: Online databases (Scopus, PubMed, Web of Science, EBSCOhost, and APA PsycInfo) were searched from inception to August 2022. RESULT: A total of 24 articles were eventually included representing 3907 participants from 14 different countries. Overall, the effect of physical activity interventions on positive emotions was significant. The studies revealed that positive emotions were statistically better in the physical activity participation group than in the control group without physical activity (SMD = 0.62, 95% CI: (0.24, 1.01), (p < 0.01). Based on subgroup analyses, we found that participation in aerobic exercise for 30-60 min in adolescents aged ≥12 years had a more significant intervention effect on positive emotions. CONCLUSION: These findings indicate that the moods of children and adolescents who participate in physical activity significantly improved compared with the moods of those who do not participate in physical activity. The age, exercise type, and exercise duration of adolescents are important factors influencing the positive emotions resulting from physical activity interventions.
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Afeto , Exercício Físico , Criança , Humanos , AdolescenteRESUMO
Tooth removal, particularly for patients with severe periodontitis, can frequently cause massive bleeding, postoperative infection, and bone resorption, resulting in a dry socket. Thus, developing bio-multifunctional materials with excellent antibacterial, hemostatic, and osteogenic characteristics for the prevention of dry sockets after tooth removal is highly desirable in clinical applications. Herein, chitosan-CaP microflowers (CM) and metronidazole (MD) loaded calcium alginate (CA) sponges (CA@CM/MD) with enhanced antibacterial, hemostatic, and osteogenic properties were developed via Ca2+ crosslinking, lyophilization, and electrostatic interaction for the prevention of dry socket after tooth removal. The fabricated CM particles display 3-dimensional, relatively homogeneous, and flower-shaped architectures. The CA@CM/MD composite sponges were facilely shaped into the tooth root as well as exhibit interconnected porous and lamellar structures with remarkable porosity, suitable maximum swelling ratio, as well as excellent compressive and hemostatic performance. Besides, the in vitro cellular assessment demonstrates that the prepared CA@CM/MD composite sponges possess satisfactory cytocompatibility. Importantly, the designed sponges significantly suppress the growth of S. aureus and E. coli, as well as promote cellular osteogenic differentiation by upregulating the formation of alkaline phosphatase. Our findings indicate that the tooth root-shaped composite sponges hold great promise for wound management after tooth removal.
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Quitosana , Alvéolo Seco , Hemostáticos , Alginatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Quitosana/farmacologia , Escherichia coli , Hemostáticos/química , Hemostáticos/farmacologia , Humanos , Metronidazol/farmacologia , Osteogênese , Porosidade , Staphylococcus aureus , Extração DentáriaRESUMO
The inability of commercial personal protective equipment (PPE) to inactivate microbes in the droplets/aerosols they intercept makes used PPE a potential source of cross-contamination. To make PPE spontaneously and continuously antimicrobial, we incorporate PPE with oxidase-like catalysts, which efficiently convert O2 into reactive oxygen species (ROS) without requiring any externally applied stimulus. Using a single-atom catalyst (SAC) nanoparticle containing atomically dispersed copper atoms as the reactive centers (Cu-SAC) and a silver-palladium bimetallic alloy nanoparticle (AgPd0.38) as models for oxidase-like catalysts, we show that the incorporation of oxidase-like catalysts enables PPE to inactivate bacteria in the droplets/aerosols they intercept without requiring any externally applied stimulus. Notably, this approach works both for PPE that are fibrous and woven such as a commercial KN95 facial respirator and for those made of solid plastics such as an apron. This work suggests a feasible and global approach for preventing PPE from spreading infectious diseases.
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Anti-Infecciosos , Equipamento de Proteção Individual , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Oxirredutases , Pessoal de Saúde , Aerossóis , Anti-Infecciosos/farmacologiaRESUMO
Light utilization largely governs the performance of CO2 photoconversion, whereas most of the materials that are implemented in such an application are restricted in a narrow spectral absorption range. Plasmonic metamaterials with a designable regular pattern and facile tunability are excellent candidates for maximizing light absorption to generate substantial hot electrons and thermal energy. Herein, a concept of coupling a Au-based stacked plasmonic metamaterial with single Cu atoms in alloy, as light absorber and catalytic sites, respectively, is reported for gas-phase light-driven catalytic CO2 hydrogenation. The metamaterial structure works in a broad spectral range (370-1040 nm) to generate high surface temperature for photothermal catalysis, and also induces strong localized electric field in favor of transfer of hot electrons and reduced energy barrier in CO2 hydrogenation. This work unravels the significant role of a strong localized electric field in photothermal catalysis and demonstrates a scalable fabrication approach to light-driven catalysts based on plasmonic metamaterials.
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Various single metal sites supported on N-doped carbon materials have been demonstrated to be effective catalysts for CO2 electroreduction. However, it remains a challenging task to gain comprehensive understanding on how the local electronic structures of single metal catalytic sites are rationally tuned, which eventually holds the key to significantly enhance the electrocatalytic performance. Herein, we implement B-N bonds into an N-doped 3D graphene framework by B doping to further stabilize the supported catalytic Ni single-sites and simultaneously tune their local electronic structure. Moreover, electrochemical in situ Fourier-transform infrared spectroscopy reveals that the B-N bonds can further facilitate the production of pivotal *COOH intermediates in comparison with only N doping. As a result, the Ni single-site catalyst on the B, N co-doped 3D graphene framework achieves excellent catalytic performance with a CO faradaic efficiency (FE) of 98% and a turnover frequency (TOF) value of 20.1 s-1 at -0.8 V (vs. RHE), whereas the FE and TOF for the control sample without B doping are as low as 62% and 6.0 s-1, respectively. This work highlights the superiority of modulating local electronic structures of single-site catalysts toward efficient electrocatalytic CO2 reduction.
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Carbon-supported single-atom catalysts (SACs) are extensively studied because of their outstanding activity and selectivity toward a wide range of catalytic reactions. Amidst its development, excess dopants (e.g., nitrogen) are always required to ensure the high loading content of SACs on the carbon support. However, the use of excess dopants is accompanied by formation of miscellaneous structures (particularly the uncoordinated N species) on catalysts, leading to adverse effects on their performance. Herein, the synthesis of carbon-supported Ni SACs with precisely controlled single-atom structure via joule heating strategy, showing the coordination of 80% of N dopants with metal elements, is reported. The preclusion of the unfavorable N species is confirmed to be the main reason for the superior performance of optimized Ni SACs in electrocatalytic carbon dioxide reduction reaction, which demonstrates unprecedented activity, selectivity, and stability under an exceptionally broad voltage range (>92% CO selectivity in the range of -0.7 to -1.9 V reversible hydrogen electrode). Such a synthetic strategy is further applicable for the design of SACs with various metals. This work demonstrates a facile method for preclusion of unfavorable dopants in the SACs and its importance in catalytic application.
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Physical activity (PA) and nutrition are the essential components of a healthy lifestyle, as they can influence energy balance, promote functional ability of various systems and improve immunity. Infections and their associated symptoms are the common and frequent challenges to human health that are causing severe economic and social consequences around the world. During aging, human immune system undergoes dramatic aging-related changes/dysfunctions known as immunosenescence. Clinically, immunosenescence refers to the gradual deterioration of immune system that increases exposure to infections, and reduces vaccine efficacy. Such phenomenon is linked to impaired immune responses that lead to dysfunction of multiple organs, while lack of physical activity, progressive loss of muscle mass, and concomitant decline in muscle strength facilitate immunosenescence and inflammation. In the present review, we have discussed the role of nutrition and PA, which can boost the immune system alone and synergistically. Evidence suggests that long-term PA is beneficial in improving immune system and preventing various infections. We have further discussed several nutritional strategies for improving the immune system. Unfortunately, the available evidence shows conflicting results. In terms of interaction with food intake, PA does not tend to increase energy intake during a short time course. However, overcoming nutritional deficiencies appears to be the most practical recommendation. Through the balanced nutritious diet intake one can fulfill the bodily requirement of optimal nutrition that significantly impacts the immune system. Supplementation of a single nutrient as food is generally not advisable. Rather incorporating various fruits and vegetables, whole grains, proteins and probiotics may ensure adequate nutrient intake. Therefore, multi-nutrient supplements may benefit people having deficiency in spite of sufficient diet. Along with PA, supplementation of probiotics, bovine colostrum, plant-derived products and functional foods may provide additional benefits in improving the immune system.
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Acting by producing reactive oxygen species (ROS) in situ, nanozymes are promising as antimicrobials. ROS' intrinsic inability to distinguish bacteria from mammalian cells, however, deprives nanozymes of the selectivity necessary for an ideal antimicrobial. Here we report that nanozymes that generate surface-bound ROS selectively kill bacteria over mammalian cells. This result is robust across three distinct nanozymes that universally generate surface-bound ROS, with an oxidase-like silver-palladium bimetallic alloy nanocage, AgPd0.38, being the lead model. The selectivity is attributable to both the surface-bound nature of ROS these nanozymes generate and an unexpected antidote role of endocytosis. Though surface-bound, the ROS on AgPd0.38 efficiently eliminated antibiotic-resistant bacteria and effectively delayed the onset of bacterial resistance emergence. When used as coating additives, AgPd0.38 enabled an inert substrate to inhibit biofilm formation and suppress infection-related immune responses in mouse models. This work opens an avenue toward biocompatible nanozymes and may have implication in our fight against antimicrobial resistance.
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Antibacterianos/farmacologia , Anti-Infecciosos/química , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Animais , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Camundongos , Testes de Sensibilidade MicrobianaRESUMO
BACKGROUND AND OBJECTIVE: China has experienced a rapid increase in the number of obese and overweight children, and sedentary behavior has been recognized as an important factor. The purpose of this review is to summarize studies on the relationship between sedentary behavior and obesity in school-age children in China. METHODS: A systematic search was conducted to identify studies that investigate the relationship between sedentary behavior and obesity in children between the ages of 6 and 18 years in China. Two researchers independently screened studies, assessed their methodological quality, and extracted relevant data. Findings on the relationship between sedentary behavior and obesity in children were synthesized and analyzed. RESULTS: A total of 17 studies were included in the review. Fifteen out of 17 studies indicated that spending too much time engaged in sedentary behavior, especially screen-based sedentary behavior, was associated with obesity in children and adolescents in China. Possible reasons for this association are less energy expenditure, increased energy intake, and insufficient sleep owing to overtime sedentary behavior. Moreover, seven, six, and three studies justified children's physical activity, dietary intake, or sleep, and most of the studies (five, three, and two) indicated that association between sedentary behavior and obesity is independent of these justified variables. Although differences in gender and area of residence in the association between sedentary behavior and obesity were examined in five studies, definite conclusions could not be drawn because of inconsistent findings or limited research. CONCLUSION: Future research is necessary to enhance understanding of demographic differences in the association between sedentary behavior and obesity in children as well as on the contributions of different types of sedentary behavior to child obesity in China.
Assuntos
Obesidade Infantil , Adolescente , Criança , China/epidemiologia , Humanos , Sobrepeso , Obesidade Infantil/epidemiologia , Instituições Acadêmicas , Comportamento SedentárioRESUMO
In this paper, four types of landscape structures and their green-land landscape patterns, including the landscapes of dominant green-land patch pattern, even green-land patch pattern, dominant wooded corridor pattern and building or concrete covering pattern (control) in the central district of Yichang city in Hubei Province, were analyzed respectively on the basis of landscape ecological theory. The atmospheric noise and the contents of SO2, NOx and total suspension particle (TSP) of the landscapes were monitored respectively by comparative method. The results showed that the landscape of building or concrete covering pattern (control) was mostly composed of woodless corridors and building or concrete covering patches with the tiptop green-land fragmentation index (18.125 3 ind x hm(-2)) and only had 1.00% green-land coverage, which had a relatively higher atmospheric noise and the highest TSP content in the landscape. The landscape of dominant green-land patch pattern had the highest green-land coverage (up to 43.59%) dominated by great green-land patches and the least fragmentation index (0.453 9 ind x hm(-2)), in which, the atmospheric noise weakened by 28.12% and the TSP content reduced significantly by 86.42%, comparing to the control. The landscape of even green-land patch pattern had the relatively lower green-land coverage (11.34%) and fragmentation index (2.751 1 ind x hm(-2)), which was mainly composed of the middle or small green-land patches and wooded corridors with a regular distribution. In the landscape, the TSP content reduced obviously by 46.62% of the control, while the effect of dust retention was only 53.95% of that in the landscape of dominant green-land patch pattern. In the landscape of dominant wooded corridor pattern, which was a traffic center and turned into a main pollution resource in the city, there were a relatively higher green-land fragmentation index (6.870 0 ind x hm(-2)) and the highest wooded corridor density (0.844 3 hm x hm(-2)) with only 6.13% green-land coverage, and the atmospheric noise and the TSP and NOx content increased by 21.47%, 5.08% and 9.06%, respectively, comparing to control. It was obvious that the greater the average area of the green-land patch and the lower the fragmentation index of green-land patches, the more effective the green-land on purifying air pollution.