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Metal-organic frameworks (MOFs) have shown great prospects in wastewater remediation. However, the easy aggregation, difficult separation and inferior reusability greatly limit their large-scale application. Herein, we proposed a facile, green and low-cost strategy to construct robust and stable MOF-based hydrogel beads (Fe-BTC-HBs) in a gram scale, and employed them to remove antibiotics from wastewater. As a result, the Fe-BTC-HBs demonstrated outstanding adsorption capacity for both ofloxacin (OFL) and tetracycline (TC) (281.17 mg/g for OFL and 223.60 mg/g for TC) under a near-neutral environment. The main adsorption mechanisms of OFL and TC were hydrogen bonding and π-π stacking interaction. Owing to its macroscopic granule and stable structure, Fe-BTC-HBs can be separated rapidly from wastewater after capturing antibiotics, and more than 85% adsorption capacity still remained after six cycles, while the powdered Fe-BTC only showed less than 6% recovery efficiency with massive weight loss (around 92%). In real industrial effluent, the adsorption performance of Fe-BTC-HBs toward two antibiotics exhibited negligible decreases (2.9% for OFL and 2.2% for TC) compared with that in corresponding solutions. Furthermore, Fe-BTC-HBs also had appealing economic and environmental benefit. Overall, the macro-manufactured MOF beads have the promising potential for the large-scale wastewater treatment.
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Estruturas Metalorgânicas , Poluentes Químicos da Água , Antibacterianos/química , Águas Residuárias , Poluentes Químicos da Água/química , Tetraciclina , Adsorção , CinéticaRESUMO
Glutamate (Glu) is an excitatory neurotransmitter that plays a critical role in memory. Brain mapping activities of such pathways relied heavily on the ability to release Glu with spatiotemporal precision. Several photo-protecting groups (PPGs), referred to as photocages or cages, were designed to accomplish the release of Glu upon irradiation. Previously reported Glu cages responded to UV upon irradiation with single photons, which limited their use in vivo experiments due to cytotoxicity. Other caged designs suffered from lower quantum efficiency (QE) of release necessitating higher concentrations and/or longer photoirradiation times. There have been limited examples of cages that respond to visible light with single photon irradiation. Herein, we report the efficient preparation of 11 caged Glu examples that respond to two visible wavelengths, 467 nm (thiocoumarin based) and 515-540 nm (BODIPY based). The kinetics of photouncaging were studied for all caged designs, and we report all quantum efficiencies, i.e., quantum yields (Φ), that ranged from 0.0001-0.65. Two of the BODIPY cages are reported here for the first time, and one, Me-BODIPY-Br-Glu, shows the most efficient Glu release with a QE of 0.65. Similar caged designs can be extended to the inhibitory neurotransmitter, GABA. This would enable the use of two visible wavelengths to modulate the release of excitatory and inhibitory neurotransmitters upon demand via optical control.
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BACKGROUND: A major shift in the "dynamic zero-COVID" policy was announced by China's National Health Commission on December 7, 2022, and the subsequent immediate large-scale outbreak of SARS-CoV-2 infections in the entire country has caused worldwide concern. This observational cross-sectional study aimed to describe the epidemiological characteristics of this outbreak in Sichuan, China. METHODS: All data were self-reported online by volunteers. We described the epidemic by characterizing the infection, symptoms, clinical duration, severity, spatiotemporal clustering, and dynamic features of the disease. Prevalence ratio (PR), Odds ratios (ORs) and adjusted ORs were calculated to analyze the associations between risk factors and infection and the associations of risk factors with clinical severity using log-binomial and multivariable logistic regression models; 95% confidence intervals (CIs) and Wald test results were reported. The prevalence rates and clinical severity among different subgroups were compared using the Chi-square and trend Chi-square tests. RESULTS: Between January 6 and 12, 2023, 138,073 volunteers were enrolled in this survey, and 102,645 were infected with COVID-19, holding a prevalence rate of 74.34%; the proportion of asymptomatic infections was 1.58%. Log-binomial regression revealed that the risk of infection increased among those living in urban areas. Multivariable logistic regression analysis showed that female sex, chronic diseases, older age and the fewer doses of vaccine received were associated with an increased risk of severe clinical outcomes after infection. We estimated the mean reproduction number during this pandemic was 1.83. The highest time-dependent reproduction number was 4.15; this number decreased below 1 after 11 days from December 7, 2022. Temporal trends revealed a single peak curve with a plateau pattern of incidence during the outbreak, whereas spatiotemporal clustering analysis showed that the onset in 21 cities in the Sichuan province had four-wave peaks. CONCLUSIONS: The peak of the first wave of Omicron infection in Sichuan Province had passed and could be considered a snapshot of China under the new control strategy. There were significant increases in the risk of severe clinical outcomes after infection among females, with chronic diseases, and the elderly. The vaccines have been effective in reducing poor clinical outcomes.
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COVID-19 , Idoso , Feminino , Humanos , China/epidemiologia , Doença Crônica , COVID-19/epidemiologia , Estudos Transversais , Surtos de Doenças/prevenção & controle , SARS-CoV-2 , Inquéritos e Questionários , MasculinoRESUMO
The ecological environment of tourism-oriented towns is attracting increasing attention. Taking the cities of Haikou and Sanya as examples, we examined changes in six ecosystem services (ES), including water conservation (WC), crop production (CP), soil retention (SR), carbon storage (CS), habitat quality (HQ), and tourism recreation (TR) from 2005 to 2020. From the three perspectives of geographical environment, socioeconomic development, and tourism development force, 14 indicators were chosen to examine the impact on ES. Except for Haikou's TR, the other ES of Haikou and Sanya showed a decreasing trend from 2005 to 2020. The values of six ES were lower in coastal zones than in noncoastal zones, which were more obvious in Sanya. Specifically, the areas of low value in Sanya were concentrated in the coastal region, and the areas with low value in Haikou were primarily distributed in blocks along the coast and in bands or points in the central and southern areas. From the perspective of influencing factors, the natural environmental factors dominate in Haikou, followed by the socio-economic factors and finally the tourism development factors, while the natural environmental factors also dominate in Sanya, followed by the tourism development factors and finally the socio-economic factors. We provided recommendations for sustainable tourism development in Haikou and Sanya. This study has significant implications for both integrated management and scientific decision-making to enhance the ES of tourism destinations.
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Conservação dos Recursos Naturais , Turismo , China , Cidades , Ecossistema , Meio Ambiente , SoloRESUMO
Silver is a well-established antimicrobial agent. Conjugation of organic ligands with silver nanoparticles has been shown to create antimicrobial nanoparticles with improved pharmacodynamic properties and reduced toxicity. Twelve novel organic ligand functionalized silver nanoparticles (AgNPs) were prepared via a light-controlled reaction with derivatives of benzothiazole, benzoxazine, quinazolinone, 2-butyne-1,4-diol, 3-butyne-1-ol, and heptane-1,7-dioic. UV-vis, Fourier-transform infrared (FTIR) spectroscopy, and energy-dispersive X-ray (EDAX) analysis were used to confirm the successful formation of ligand-functionalized nanoparticles. Dynamic light scattering (DLS) revealed mean nanoparticle diameters between 25 and 278 nm. Spherical and nanotube-like morphologies were observed using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Seven of the twelve nanoparticles exhibited strong antimicrobial activity and five of the twelve demonstrated significant antibacterial capabilities against E. coli in a zone-of-inhibition assay. The synthesis of functionalized silver nanoparticles such as the twelve presented is critical for the further development of silver-nanoconjugated antibacterial agents.
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Nanopartículas Metálicas , Prata , Prata/farmacologia , Prata/química , Escherichia coli , Nanopartículas Metálicas/química , Ligantes , Antibacterianos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/química , Testes de Sensibilidade MicrobianaRESUMO
Clay minerals can adsorb both microorganisms and heavy metals. In this study, typical soil bacterium, Enterobacter sp. was applied to investigate the potential protection of the bacterial cells from Pb2+ stress by clay minerals. The sorption by two representative types of montmorillonite (Mt) were contrasted, i.e., Mts/Mtw with strong/weak CEC. There was no significant difference between the two clay minerals regarding their adsorption of Pb2+ cations in water (i.e., ~55 mg L-1). However, the sorption of bacterial cells on the two clay minerals showed evident contrasts, which resulted in the different capacity of Pb sorption. Mts with high CEC preferentially adsorbed abundant bacterial cells (rather than Pb2+) on its surface. The residual Pb2+ concentration in solution actually raised by 7.5% after the addition of Enterobacter sp. In addition, both the Pb-contaminated cells and "healthy" cells (with low Pb contamination) could be adsorbed onto Mt surface, whereas the latter dominated the adsorbents on Mts. This was due to that the Mts with high CEC could provide more exchangeable cations, building more cation bridging ligands between the microbial cells (whatever the types of cells) and clay surface. Furthermore, the adsorbed "healthy" bacterial cells might escape from clay surface via "self-liberating" mechanism, i.e., increasing electrostatic repulsion between the bacteria and clay during microbial decomposition of the medium. This study hence elucidated the protection of microorganisms from Pb2+ stress by Mt.
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Argila/química , Enterobacter/efeitos dos fármacos , Chumbo/toxicidade , Poluentes do Solo/toxicidade , Adsorção , Bentonita/química , Cátions/química , Enterobacter/metabolismo , Chumbo/química , Metais Pesados/química , Minerais/química , Poluentes do Solo/químicaRESUMO
The demand for Internet of Things services is increasing exponentially, and consequently a large number of devices are being deployed. To efficiently authenticate these objects, the use of physical unclonable functions (PUFs) has been introduced as a promising solution for the resource-constrained nature of these devices. The use of machine learning PUF models has been recently proposed to authenticate the IoT objects while reducing the storage space requirement for each device. Nonetheless, the use of a mathematically clonable PUFs requires careful design of the enrollment process. Furthermore, the secrecy of the machine learning models used for PUFs and the scenario of leakage of sensitive information to an adversary due to an insider threat within the organization have not been discussed. In this paper, we review the state-of-the-art model-based PUF enrollment protocols. We identity two architectures of enrollment protocols based on the participating entities and the building blocks that are relevant to the security of the authentication procedure. In addition, we discuss their respective weaknesses with respect to insider and outsider threats. Our work serves as a comprehensive overview of the ML PUF-based methods and provides design guidelines for future enrollment protocol designers.
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Internet das Coisas , Segurança Computacional , Confidencialidade , Aprendizado de MáquinaRESUMO
A series of Ca15(PO4)2(SiO4)6:xCe3+,yTb3+ phosphors have been prepared by a high-temperature solid-state reaction. Under the excitation of near-UV with 371 nm wavelength, Ca15(PO4)2(SiO4)6:xCe3+ phosphors exhibit strong blue emission with a broad peak at 432 nm. Based on the photoluminescence of Ca15(PO4)2(SiO4)6:xCe3+ phosphors, the coordination environment around Ce3+ ions and the concentration quenching mechanism are inferred. With the doping of Tb3+ ions into Ca15(PO4)2(SiO4)6:1.33%Ce3+, the luminescence color from blue to cyan can be well tuned. By measuring the luminescence intensity and lifetime of the as-prepared phosphors, it can be judged that there exists an energy transfer from Ce3+ to Tb3+. To achieve white light, the optimal Ca15(PO4)2(SiO4)6:1.33%Ce3+, 9%Tb3+ phosphors are mixed with commercial SrAlSiN3:Eu2+ powders and finally warm white light emission could be obtained. The results show that Ca15(PO4)2(SiO4)6:xCe3+,yTb3+ phosphors have potential applications in warm white light-emitting diodes.
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The red yeast (Rhodotorula mucilaginosa: Rho) has abundant extracellular polymeric substances (EPS) and intracellular vesicles (Ves). This study explored the mechanisms of Rho to resist Cu toxicity from extracellular to intracellular, i.e., EPS, membrane, and Ves. The Cu2+ concentrations were set from 0 to 200 mg/L. In contrast to other heavy metals (e.g., Pb2+), low Cu2+ stress has no evident stimulation to EPS production. In particular, GSH content in EPS did not show significant changes. The Cu removal was decreased from ~ 35 to ~ 0% as Cu stress raised from 0 to 200 mg/L, which confirmed the low binding of Cu cations to EPS. Moreover, redox peaks at - 0.35 V (reduction) and - 0.02 V (oxidation) in EPS were observed based on electrochemical analysis. Subsequently, the potential Haber-Weiss reaction in EPS lowered fungal ability to shield against the Cu toxicity. Then, the contrast of Cu concentration between the extracellular and intracellular regions was enlarged. Moreover, the thickness of cell membrane decreased from 450 to 116 nm during the elevation of Cu stress. These accelerated the transport of Cu cations into intracellular, but the redox reaction in both cell membrane and intracellular region was limited. Under transmission electron microscopy, the intracellular Ves showed evident sorption of Cu cations (100 mg/L). However, the Ves started to deform and gradually lost their activity at 200 mg/L. Therefore, this study successfully elucidated the correlated extracellular and intracellular mechanisms of metal detoxification by yeast. KEY POINTS: â¢This study provides a comprehensive explanation for the invasion of Cu2+ into fungal (Rhodotorula mucilaginosa) cells based on microbial physiological and biochemical analysis, electrochemical analysis, and transmitted electron microscopy. â¢Cu nanoparticles are involved in redox reactions in the EPS, thus greatly reducing the prophase protection for fungal cells by EPS. â¢At 200 mg/L Cu2+ stress, deformation of cell membrane intensifies the contrast of Cu concentrations between extra- and intracellular regions. This further suppresses the transportation of Cu2+ by intracellular vesicles. Graphical abstract.
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Produtos Biológicos , Metais Pesados , Rhodotorula , Matriz Extracelular de Substâncias PoliméricasRESUMO
Background: Noise exposure and the risk of cognitive impairment are currently major public health issues. Objective: This study aimed to analyze the relationship between noise exposure and early impairment of cognitive function from the perspective of occupational epidemiology and to provide evidence for the long-term prevention and treatment of dementia in the context of aging. Methods: This study was conducted in China between May and August 2021. The independent variables were the type of hazardous factors, duration of noise exposure, perceived noise intensity, and cumulative noise exposure (CNE). The dependent variable was cognitive function, which was measured using the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). Multiple linear and logistic regression were used to analyze the relationship between noise exposure and cognitive function and to establish an effect curve. Results: The detection rates of cognitive dysfunction using the MMSE and MoCA were 1.1% and 36.2%, respectively. The predicted MMSE and MoCA scores showed a downward trend within the CNE value ranging from 90-140âdB.time. Each unit increase in CNE decreased cognitive function scores by 0.025 (0.037, 0.013) and 0.020 (0.037, 0.003) points,respectively. Conclusions: From the perspective of occupational epidemiology, these findings reveal a potential link between long-term noise exposure and early cognitive impairment.
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Disfunção Cognitiva , Testes de Estado Mental e Demência , Exposição Ocupacional , Humanos , China/epidemiologia , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Masculino , Estudos Transversais , Feminino , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Idoso , Ruído Ocupacional/efeitos adversos , Adulto , Testes NeuropsicológicosRESUMO
Carbon-fiber-reinforced polymer (CFRP) composites are widely used in lightweight structures because of their high specific strength, specific modulus, and low coefficient of thermal expansion. Additionally, the unidirectionally arrayed chopped strand (UACS) laminates have excellent mechanical properties and flowability, making them suitable for fabricating structures with complex geometry. In this paper, the damage process of UACS quasi-isotropic laminates under tensile load was tested using acoustic emission detection technology. The mechanical properties and damage failure mechanism of UACS laminates were studied combined with finite element calculation. By comparing and analyzing the characteristic parameters of acoustic emission signals such as amplitude, relative energy, and impact event, it is found that acoustic emission behavior can accurately describe the damage evolution of specimens during loading. The results show that the high-amplitude signals representing fiber fracture in continuous fiber laminates are concentrated in the last 41%, while in UACS laminates they are concentrated in the last 30%. In UACS laminates, more of the damage is caused by matrix cracks and delamination with medium- and low-amplitude signals, which indicates that UACS laminates have a good suppression effect on damage propagation. The stress-strain curves obtained from finite element analysis agree well with the experiment results, showing the same damage sequence, which confirms that the model described in this research is reliable.
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Stretchable electrodes based on liquid metals (LM) are widely used in human-machine interfacing, wearable bioelectronics, and other emerging technologies. However, realizing the high-precision patterning and mechanical stability remains challenging due to the poor wettability of LM. Herein, a method is reported to fabricate LM-based multilayer solid-liquid electrodes (m-SLE) utilizing electrohydrodynamic (EHD) printed confinement template. In these electrodes, LM self-assembled onto these high-resolution templates, assisted by selective wetting on the electrodeposited Cu layer. This study shows that a m-SLE composed of PDMS/Ag/Cu/EGaIn exhibits line width of ≈20 µm, stretchability of ≈100%, mechanical stability ≈10 000 times (stretch/relaxation cycles), and recyclability. The multi-layer structure of m-SLE enables the adjustability of strain sensing, in which the strain-sensitive Ag part can be used for non-distributed detection in human health monitoring and the strain-insensitive EGaIn part can be used as interconnects. In addition, this study demonstrates that near field communication (NFC) devices and multilayer displays integrated by m-SLEs exhibit stable wireless signal transmission capability and stretchability, suggesting its applicability in creating highly-integrated, large-scale commercial, and recyclable wearable electronics.
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BACKGROUND: Traffic-related air pollution (TRAP) is hypothesised to play a role in the development of allergic rhinitis (AR). Prenatal and early-life exposure to traffic-related air pollution is considered critical for later respiratory health. However, we could not find any articles systematically reviewing the risk of prenatal and early-life exposure to traffic-related air pollution for allergic rhinitis in children. METHODS: A systematic literature search of PubMed, Web of Science and Medline was conducted to identify studies focused on the association between prenatal and early-life exposure to TRAP and AR in children. Other inclusion criteria were: 1) original articles; 2) based upon prospective or retrospective studies or case-control studies; and 3) publications were restricted to English. Literature quality assessment was processed using the Newcastle-Ottawa Scale (NOS) evaluation scale. This systematic literature review has been registered on the prospero (crd.york.ac.uk/prospero) with the following registry number: CRD42022361179. RESULTS: Only eight studies met the inclusion criteria. The exposure assessment indicators included PM2.5, PM2.5 absorbance, PM10, NOx, CO, and black carbon. On the whole, exposure to TRAP during pregnancy and the first year of life were positively associated with the development of AR in children. CONCLUSIONS: This systematic review presents supportive evidence about prenatal and early-life exposure to TRAP and the risk of AR in children.
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Poluentes Atmosféricos , Poluição do Ar , Rinite Alérgica , Gravidez , Feminino , Humanos , Criança , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Estudos Prospectivos , Estudos Retrospectivos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Rinite Alérgica/epidemiologia , Rinite Alérgica/etiologia , Vitaminas , Material Particulado/análiseRESUMO
Hydrogen evolution reaction (HER) coupled with biomass conversion is a sustainable route to produce clean energy H2 and value-added chemicals simultaneously. Herein, an amorphous Ni-Mo-B-O bifunctional electrocatalyst was synthesized through a facile electrodeposition method and employed as a cathode for HER to produce H2 and as an anode for the conversion of hydroxymethylfurfural (HMF) to furandicarboxylic acid (FDCA). Besides leading to the formation of amorphous structures, the introduction of Mo and B can increase the electron density and optimize the electronic structure of the electrocatalyst, thus substantially increasing the catalytic activity of the catalyst. After continuous reaction at a constant potential of 0.58â V vs. Hg/HgO for 8â hours, the conversion of HMF reached 98.86 %, and the selectivity of the target product FDCA was as high as 92.97 %. Finally, a two-electrolyzer system was constructed using the amorphous Ni-Mo-B-O as both cathode and anode to achieve simultaneous H2 production in the cathode chamber and FDCA production in the anode chamber at a low voltage. This work presents a promising strategy for the design and synthesis of high-performance non-noble metal electrocatalysts for efficient and cost-effective H2 production.
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BACKGROUND: To analyze the diagnosis performance of deep learning model used in corona virus disease 2019 (COVID-19) computer tomography(CT) chest scans. The included sample contains healthy people, confirmed COVID-19 patients and unconfirmed suspected patients with corresponding symptoms. METHODS: PubMed, Web of Science, Wiley, China National Knowledge Infrastructure, WAN FANG DATA, and Cochrane Library were searched for articles. Three researchers independently screened the literature, extracted the data. Any differences will be resolved by consulting the third author to ensure that a highly reliable and useful research paper is produced. Data were extracted from the final articles, including: authors, country of study, study type, sample size, participant demographics, type and name of AI software, results (accuracy, sensitivity, specificity, ROC, and predictive values), other outcome(s) if applicable. RESULTS: Among the 3891 searched results, 32 articles describing 51,392 confirmed patients and 7686 non-infected individuals met the inclusion criteria. The pooled sensitivity, the pooled specificity, positive likelihood ratio, negative likelihood ratio and the pooled diagnostic odds ratio (OR) is 0.87(95%CI [confidence interval]: 0.85, 0.89), 0.85(95%CI: 0.82, 0.87), 6.7(95%CI: 5.7, 7.8), 0.14(95%CI: 0.12, 0.16), and 49(95%CI: 38, 65). Further, the AUROC (area under the receiver operating characteristic curve) is 0.94(95%CI: 0.91, 0.96). Secondary outcomes are specific sensitivity and specificity within subgroups defined by different models. Resnet has the best diagnostic performance, which has the highest sensitivity (0.91[95%CI: 0.87, 0.94]), specificity (0.90[95%CI: 0.86, 0.93]) and AUROC (0.96[95%CI: 0.94, 0.97]), according to the AUROC, we can get the rank Resnet > Densenet > VGG > Mobilenet > Inception > Effficient > Alexnet. CONCLUSIONS: Our study findings show that deep learning models have immense potential in accurately stratifying COVID-19 patients and in correctly differentiating them from patients with other types of pneumonia and normal patients. Implementation of deep learning-based tools can assist radiologists in correctly and quickly detecting COVID-19 and, consequently, in combating the COVID-19 pandemic.
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COVID-19 , Aprendizado Profundo , Humanos , COVID-19/diagnóstico por imagem , Pandemias , SARS-CoV-2 , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , ComputadoresRESUMO
Thermal ablation is an efficient method of medical treatment, such as cancer therapy, wound closure, laser cutting, freckle removal and other treatments. In order to guarantee the curative effect and the safety of the patients, the thermal response of the tissue which is subjected to the heat source need to be carefully monitored. However, it is too difficult to achieve real-time monitoring on the full-field temperature. In the present study, efforts were made to build up a theoretical model for the prediction of the thermal response in the human skin. The Dual-Phase-Lag (DPL) bio-heat transfer model and the Henrique's burn assessment model were employed to describe the interaction of multi-pulse heat source and the skin. The repeated multi-pulse laser is a common heat source in the thermal treatment and the thermal responses of the skin would be complicated under the common effects of the non-Fourier effects and the multi-pulse source. The Green's function approach was used to solve the governing equations analytically. The closed-form solution for the temperature distribution of the skin was obtained and the thermal damage was estimated based on the temperature results. The influences of the biological parameters (the phase lags of the heat flux and the temperature gradient) and the heat source parameters (the pulse number and the duty ratio) on the temperature distribution, the burn degree and the irreversible burn depth of the irradiated region were discussed.
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Procedimentos Cirúrgicos Dermatológicos/métodos , Terapia a Laser/métodos , Termografia/métodos , Biologia Computacional/métodos , Simulação por Computador , Temperatura Alta , Humanos , Hipertermia Induzida/métodos , Lasers , Modelos Biológicos , Modelos Teóricos , Pele/metabolismo , Temperatura , Condutividade TérmicaRESUMO
The study of the spatial-temporal pattern and social performance of urban public services is a basic task for achieving urban fairness and justice. Through spatial analysis and social performance evaluation, this study explores the evolution of spatial-temporal patterns and the social performance of community sports and fitness venues in Shanghai from 1982 to 2019. The results show that the construction of Shanghai's community sports and fitness venues presents the evolution pattern of "urbanization-suburbanization-reurbanization". The center of construction has always been in the urban area and first moved toward the south and then toward the north. Government investment was the main source of funds for the construction of venues, and social investment has been steadily growing. The number and area of multiple types of venues has increased significantly, including trails, gymnasiums, and courts. The overall service coverage radius of Shanghai's community sports and fitness venues has been significantly increased, and the regional equality between the core and peripheral areas has been obviously improved. The overall per capita service location entropy has not been significantly improved. The old city center and the peripheral area have always been the low-value areas, and the old city center is surrounded by high-value areas. The "low-high-low" three-circle spatial structure continues to exist, but around the old city center, the scope of the high-value area has expanded markedly. There was a significant optimization of social performance from 1999 to 2009. The social performance of the community sports and fitness venues in urban areas is better than that in suburban areas, but the optimization of social performance in suburban areas is greater than that in urban areas. The above analysis is expected to provide references for rationally arranging urban sports and fitness spaces, enhancing the fairness of urban public services, improving the quality of residents' lives, and assisting the implementation of the "Healthy China" national strategy.
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Esportes , Urbanização , China , Cidades , Humanos , População SuburbanaRESUMO
The thermal damage of a three-dimensional bio-tissue model irradiated by a movable laser beam was studied in this work. By employing the DPL biological heat conduction model and Henriques' thermal damage assessment model, the distribution of burn damage of vivo human tissue during laser therapy was analytically obtained. The influences of laser moving velocity, laser spot size, phase lags of heat flux and temperature gradient were discussed. It was found that the laser moving speed and the laser spot size greatly influence the thermal damage degree by affecting the energy concentration degree. The increases of the laser moving speed and laser spot size can enlarge the irradiated region and reduce the burn degree. A greater phase lag of temperature gradient led to lower accumulation of thermal energy and lower burn degree. However, the increment of heat flux phase lag leads to the thermal energy accumulation and more serious burn degree in the irradiated region.
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Queimaduras/etiologia , Temperatura Alta/efeitos adversos , Terapia a Laser/efeitos adversos , Algoritmos , Simulação por Computador , Humanos , Modelos Biológicos , Condutividade TérmicaRESUMO
The hyperthermia is an efficient technique for tumor treatment, in which the tumor is subjected to a heating source, such as laser, supersonic or electromagnetic field. In order to improve the therapeutic efficiency and to protect the surrounding healthy tissues, gold nanoshells are embedded in the tumor as the additive to make it absorb more thermal energy than the healthy tissues. In the present study, a one-dimensional three-layered model is established to investigate the thermal response of the bio-tissue in the hyperthermia treatment for subcutaneous tumor. The governing equations are solved analytically by using the Green's function method and the Henriques' model is employed to evaluate the degree of thermal damage in the target tissue. The influences of the volumetric density of gold nanoshells on the temperature distribution and thermal damage are discussed in detail. When the gold nanoshells are embedded with a proper density, it can improve the efficiency of tumor killing and protecting the subcutaneous tissue from being burnt. The closed-form solution for the governing equations in multilayered tissues can be a theoretical guideline to selection of appropriate parameters of the gold nanoshells.
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Hipertermia Induzida , Modelos Biológicos , Nanomedicina , Nanoconchas , Neoplasias/terapia , Tela Subcutânea/patologiaRESUMO
Porous V2O5 microspheres are synthesized via spray-drying and employed as the cathode material for aqueous zinc-ion batteries (ZIBs). The obtained porous V2O5 microspheres exhibit an ultrahigh reversible capacity and superior rate and cycling performances. In particular, a discharge capacity of 401 mA h g-1 can be achieved at 100 mA g-1. The specific energy density reaches 286 W h kg-1, surpassing most reported V-based cathode materials. The super electrochemical performances demonstrate that the porous V2O5 microsphere is a promising cathode material for aqueous ZIBs.