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In recent years, the magnitude and frequency of regional ozone (O3) episodes have increased in China. We combined ground-based measurements, observation-based model (OBM), and the Weather Research and Forecasting and Community Multiscale Air Quality (WRF-CMAQ) model to analyze a typical persistent O3 episode that occurred across 88 cities in northeastern China during June 19-30, 2021. The meteorological conditions, particularly the wind convergence centers, played crucial roles in the evolution of O3 pollution. Daily analysis of the O3 formation sensitivity showed that O3 formation was in the volatile organic compound (VOC)-limited or transitional regime at the onset of the pollution episode in 92% of the cities. Conversely, it tended to be or eventually became a NOx-limited regime as the episode progressed in the most polluted cities. Based on the emission-reduction scenario simulations, mitigation of the regional O3 pollution was found to be most effective through a phased control strategy, namely, reduction of a high ratio of VOCs to NOx at the onset of the pollution and lower ratio during evolution of the O3 episode. This study presents a new possibility for regional O3 pollution abatement in China based on a reasonable combination of OBM and the WRF-CMAQ model.
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Poluentes Atmosféricos , Poluição do Ar , Ozônio , Compostos Orgânicos Voláteis , Ozônio/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , China , Compostos Orgânicos Voláteis/análiseRESUMO
Material stability is the focus on both experiments and calculations, which includes the energetic stability at the static state and the thermodynamic stability at the kinetic state. To show whether energetics or kinetics dominates on material stability, this study focuses on the Pd13 clusters, because of their observable magnetic moment in experiment. Energetically, the CALYPSO searching method and first-principles calculations find that Pd13(C2) is the ground state at 0 K while the static frequency calculations demonstrate that the icosahedron Pd13(Ih) becomes more favorable on free energy as temperature increases. However, their magnetic moments (8 µB) are not in agreement with the experimental value (<5.2 µB). Kinetically, ab initio molecular dynamics simulations reveal that Pd13(C3v) (6 µB) has supreme isomerization temperature and the other 11 low-lying isomers transform to Pd13(C3v) directly or indirectly, demonstrating that Pd13(C3v) has the maximum probability to be observed in experiment. The magnetic moment difference between experiment (<5.2 µB) and this calculation (6 µB) may be due to the spin multiplicities. Our result suggests that the magnetic moment disparity between theory and experiment (in Pd13 clusters) originates from the kinetic stability.
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Spaceborne synthetic aperture radar (SAR) is an advanced microwave imaging technology that provides all-weather and all-day target information. However, as spaceborne SAR resolution improves, traditional echo signal models based on airborne SAR design become inadequate due to the curved orbit, Earth rotation, and increased propagation distance. In this study, we propose an accurate range model for high-resolution spaceborne SAR by analyzing motion trajectory and Doppler parameters from the perspective of the space geometry of spaceborne SAR. We evaluate the accuracy of existing range models and propose an advanced equivalent squint range model (AESRM) that accurately fits the actual range history and compensates for high-order term errors by introducing third-order and fourth-order error terms while maintaining the simplicity of the traditional model. The proposed AESRM's concise two-dimensional frequency spectrum form facilitates the design of imaging algorithms. Point target simulations confirm the effectiveness of the proposed AESRM, demonstrating significant improvements in fitting accuracy for range histories characterized by nonlinear trajectories. The developed AESRM provides a robust foundation for designing imaging algorithms and enables higher resolution and more accurate radar imaging.
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To investigate the particle sources before, during, and after the 2022 Beijing Winter Olympic and Paralympic (WOP) in Beijing, ambient particles were passively collected from January to March 2022. The physicochemical properties including morphology, size, shape parameters, and elemental compositions were analyzed by the IntelliSEM EPAS (an advanced computer-controlled scanning electron microscopy [CCSEM] system). Using the user-defined classification rules, 37,174 individual particles were automatically classified into 27 major groups and further attributed to seven major sources based on the source-associated characteristics, including mineral dust, secondary aerosol, combustion/industry, carbonaceous particles, salt-related particles, biological particles, and fiber particles. Our results showed that mineral dust (66.5%), combustion/industry (12.6%), and secondary aerosol (6.3%) were the three major sources in a wide size range of 0.2-42.8 µm. During the Winter Olympic Games period, low emission of anthropogenic particles and favorable meteorological conditions contributed to significantly improved air quality. During the Winter Paralympic Games period, more particles sourced from the dust storm, secondary formed particles, and the adverse meteorological conditions resulted in relatively worse air quality. The secondary aerosol all decreased during the competition period, while increased during the non-competition period. Sulfate-related particles had explosive growth and further aggravate the pollution degree during the non-competition period, especially under adverse meteorological conditions. These results provide microscopic evidence revealing variations of physicochemical properties and sources in response to the control measures and meteorological conditions.
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Poluentes Atmosféricos , Poluição do Ar , Pequim , Poluentes Atmosféricos/análise , Material Particulado/análise , Tamanho da Partícula , Monitoramento Ambiental , Poluição do Ar/análise , Poeira/análise , Estações do Ano , Aerossóis/análise , MineraisRESUMO
Burn patients are at high risk of central line-associated bloodstream infection (CLABSI). However, the diagnosis of such infections is complex, resource-intensive, and often delayed. This study aimed to investigate the epidemiology of CLABSI and develop a prediction model for the infection in burn patients. The study analysed the infection profiles, clinical epidemiology, and central venous catheter (CVC) management of patients in a large burn centre in China from January 2018 to December 2021. In total, 222 burn patients with a cumulative 630 CVCs and 5,431 line-days were included. The CLABSI rate was 23.02 CVCs per 1000 line-days. The three most common bacterial species were Acinetobacter baumannii, Staphylococcus aureus, and Pseudomonas aeruginosa; 76.09% of isolates were multidrug resistant. Compared with a non-CLABSI cohort, CLABSI patients were significantly older, with more severe burns, more CVC insertion times, and longer total line-days, as well as higher mortality. Regression analysis found longer line-days, more catheterisation times, and higher burn wounds index to be independent risk factors for CLABSI. A novel nomogram based on three risk factors was constructed with an area under the receiver operating characteristic curve (AUROC) value of 0.84 (95% CI: 0.782-0.898) with a mean absolute error of calibration curve of 0.023. The nomogram showed excellent predictive ability and clinical applicability, and provided a simple, practical, and quantitative strategy to predict CLABSI in burn patients.
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Bacteriemia , Queimaduras , Infecções Relacionadas a Cateter , Cateteres Venosos Centrais , Humanos , Bacteriemia/complicações , Bacteriemia/epidemiologia , Queimaduras/complicações , Infecções Relacionadas a Cateter/epidemiologia , Cateteres Venosos Centrais/efeitos adversos , Cateteres Venosos Centrais/microbiologia , Nomogramas , Estudos RetrospectivosRESUMO
Precipitation can lead to significant leaching of heavy metals from abandoned tailingsï¼resulting in a decline in the quality of the surrounding environment. This study aimed to simulate and quantify the migration patterns and fate of heavy metals in tailings caused by precipitation in various environmental media (tailings, air, water, soil, and sediments) using leaching tests, source apportionment, and a fugacity model. Results revealed that the average contents of Cd, Cu, As, Pb, Zn, and Cr in the un-weathered tailings were 3.43, 495.56, 160.70, 138.94, 536.57, and 69.52 mg/kg, respectively. The ecological risk factors in the tailings as well as in sediments and soils, were in the following order: Cd >Cu >As >Pb >Zn >Cr. A fugacity model based on the mass-balance methods was established, achieving a good agreement between simulation and measured values. The total amounts of Cd, Cu, As, Pb, and Zn leached from abandoned tailings over the 30-year evaluation period were estimated to be 1.09, 62.44, 0.16, 0.94, and 102.12 t, respectively. Soil and sediments are important reservoirs for heavy metals. The sum of the As, Cd, Cu, Pb, and Zn storage capacities in the soil and sediment accounted for 77.28%, 75.63%, 73.94%, 69.39%, and 57.80% of the total storage capacity, respectively. This study could provide the means for the establishment of a targeted pollution control plan, a guide for restoration projects, and will aid in controlling pollution risk and improving the surrounding environment.
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Metais Pesados , Poluentes do Solo , Monitoramento Ambiental , Cádmio , Chumbo , Medição de Risco , Poluentes do Solo/análise , Metais Pesados/análise , Solo , ChinaRESUMO
Progestins are mainly used in pharmacotherapy and animal husbandry and have received increasing attention as they are widely detected in various aquatic ecosystems. In this study, adult female western mosquitofish (Gambusia affinis) were exposed to different concentrations of norethindrone (NET) (solvent control, 5.0 (L), 50.0 (M), and 500.0 (H) ng/L) for 42 days. Behaviors, morphological parameters, histology of the thyroid, thyroid hormone levels (TSH, T3, and T4), and transcriptional levels of nine genes in the hypothalamic-pituitary-thyroid (HPT) axis were examined. The results showed that NET decreased sociality but increased the anxiety of G. affinis. Sociality makes fish tend to cluster, and anxiety may cause G. affinis to reduce exploration of new environments. Female fish showed hyperplasia, hypertrophy, and glial depletion in their thyroid follicular epithelial cells after NET treatment. The plasma levels of TSH and T4 were significantly reduced, but T3 concentrations were significantly increased in the fish from the H group. In addition, the transcripts of genes (tshb, tshr, tg, dio1, dio2, thrb) in the brains of fish in the M and H treatments were significantly stimulated, while those of trh and pax2a were suppressed. Our results suggest that NET may impact key social behaviors in G. affinis and interfere with the entire thyroid endocrine system, probably via affecting the transcriptional expression of upstream regulators in the HPT axis.
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Ciprinodontiformes , Glândula Tireoide , Feminino , Animais , Noretindrona , Ecossistema , Ciprinodontiformes/genética , TireotropinaRESUMO
City clusters play an important role in air pollutant and greenhouse gas (GHG) emissions reduction in China, primarily due to their high fossil energy consumption levels. The "2 + 26" Cities, i.e., Beijing, Tianjin and 26 other perfectures in northern China, has experienced serious air pollution in recent years. We employ the Greenhouse Gas and Air Pollution Interactions and Synergies model adapted to the "2 + 26" Cities (GAINS-JJJ) to evaluate the impacts of structural adjustments in four major sectors, industry, energy, transport and land use, under the Three-Year Action Plan for Blue Skies (Three-Year Action Plan) on the emissions of both the major air pollutants and CO2 in the "2 + 26" Cities. The results indicate that the Three-Year Action Plan applied in the "2 + 26" Cities reduces the total emissions of primary fine particulate matter with an aerodynamic diameter of ≤ 2.5 µm (PM2.5), SO2, NOx, NH3 and CO2 by 17%, 25%, 21%, 3% and 1%, respectively, from 2017 to 2020. The emission reduction potentials vary widely across the 28 prefectures, which may be attributed to the differences in energy structure, industrial composition, and policy enforcement rate. Among the four sectors, adjustment of industrial structure attains the highest co-benefits of CO2 reduction and air pollution control due to its high CO2 reduction potential, while structural adjustments in energy and transport attain much lower co-benefits, despite their relatively high air pollutant emissions reductions, primarily resulting from an increase in the coal-electric load and associated carbon emissions caused by electric reform policies..
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Poluentes Atmosféricos , Poluição do Ar , Gases de Efeito Estufa , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , Dióxido de Carbono/análise , China , Cidades , Mudança Climática , Monitoramento Ambiental/métodos , Gases de Efeito Estufa/análise , Material Particulado/análiseRESUMO
The electrical contact and graphene (Gr) doping for Gr/XPtY (X, Y = S, Se, and Te) van der Waals (vdW) heterostructures are studied by using first-principles methods. The intrinsic electronic properties of Gr and PtXY are preserved due to the weak vdW interactions. We find that the types of interfacial electrical contact and Gr doping are closely related to the interface chalcogen atoms. The n-type Ohmic contact is formed in the Gr/SPtY (Y = S, Se, and Te) systems. The n-type and p-type Schottky contacts are realized in the Gr/SePtY and Gr/TePtY systems, respectively. The physical mechanism of different contact types can be analyzed based on the charge transfer between the Gr and XPtY layers. For all the heterostructures, the contact type and Schottky barrier height can be effectively modulated by the external electric field and interlayer coupling. The Gr doping type and charge-carrier concentration are also investigated. The p-doping, p-doping, and n-doping are obtained in Gr for the Gr/SPtY, Gr/SePtY, and Gr/TePtY systems, respectively. The highest carrier concentration of the Gr layer can reach 1.69 × 1013 cm-2 for the Gr/TePtTe system. The results indicate that Gr/XPtY heterostructures are potential candidates for improving the performance of high-efficiency nano electronic devices.
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Mexican-hat-like band dispersion is extremely critical to the realization of hole-doping-induced magnetism in monolayer metal monochalcogenides. However, it is absent from transition-metal dichalcogenides (TMDCs), i.e., WSe2. Herein, using first-principles calculations, we show that Mexican-hat-like band dispersion can be achieved by applying interlayer strain (ε) in the WSe2/SnS2 van der Waals (vdW) heterostructure when ε exceeds 15%. This is because in the strain-induced distorted trigonal prismatic crystal field, at the valence band edge, the W_dz2 orbitals shift upward around the Γ point, while the double-degenerate W_dxy/dx2-y2 orbitals shift downward at the K point, resulting in Mexican-hat-like band dispersion near the Γ point when the energy level of the Γ point surpasses that of the K point. On account of the appearance of the Mexican-hat-like band edge (MHBE), hole-doping in the strained WSe2/SnS2 heterostructure induces magnetization readily from the nonmagnetized phase. Our findings may provide a new strategy for the realization of magnetized TMDC-based vdW heterostructures.
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Herein, the Rashba spin orbit coupling (SOC) of polar group III-VI chalcogenide XABY (A, B = Ga, In; X ≠ Y = S, Se, Te) monolayers is investigated based on density functional theory. The different electronegativities of X and Y atoms lead to an asymmetrical internal electric field in the XABY monolayer; this implies that the internal electric field between A and X is not equal to that between B and Y. Mirror symmetry breaking in the XABY monolayer induces a remarkable Rashba spin splitting (RSS) at the conduction band minimum (CBM). Moreover, it is demonstrated that an external electric field and an in-plane biaxial strain can affect the internal electric field by varying the charge distribution, and this further manipulates the RSS. Under a positive external electric field and tensile strain, the RSS at the CBM exhibits a near-linear increasing behavior, whereas under a negative external electric field and compressive strain, the RSS displays a monotonous decreasing pattern. In addition, we explored the influence of interlayer coupling and substrate on the RSS. The stacking pattern of bilayer structures has a significant impact on the RSS. The investigation of SInGaSe on the Si(111) substrate suggests that the Rashba band is situated inside the large band gap of the substrate. Overall, our investigations suggest that the polar group III-VI chalcogenides are promising candidates for future spintronic applications.
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Identification of the geometric structures of silver clusters is of great importance in future nanotechnologies due to their superior properties. Nevertheless, some ground-state structures are still in academic debate, partly because the experiments and theoretical calculations are not performed at the same temperatures. For example, silver clusters usually have compact configurations. However, a combined experimental and theoretical study proposed that the most stable structure of Ag13- had a two-coordinated atom. By using the CALYPSO approach for the global minima search followed by first-principles calculations, we discovered that a more compact trilayer Ag13- cluster was the ground state, in accordance with another three works published recently. In addition, its O2 adsorption structure is also energetically favored. By tracing characteristic bond changes in ab initio molecular dynamics (MD) simulations, we confirmed that, compared with other isomers, this trilayer structure and its O2 adsorption structure also had the highest thermal stability. This work emphasized the thermal stability concept in theoretical calculations, which may be a necessary supplement to explain the experimental observations on cluster science.
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BACKGROUND: Infectious diseases caused by multidrug-resistant (MDR) bacteria, especially MDR Gram-negative strains, have become a global public health challenge. Multifunctional nanomaterials for controlling MDR bacterial infections via eradication of planktonic bacteria and their biofilms are of great interest. RESULTS: In this study, we developed a multifunctional platform (TG-NO-B) with single NIR laser-triggered PTT and NO release for synergistic therapy against MDR Gram-negative bacteria and their biofilms. When located at the infected sites, TG-NO-B was able to selectively bind to the surfaces of Gram-negative bacterial cells and their biofilm matrix through covalent coupling between the BA groups of TG-NO-B and the bacterial LPS units, which could greatly improve the antibacterial efficiency, and reduce side damages to ambient normal tissues. Upon single NIR laser irradiation, TG-NO-B could generate hyperthermia and simultaneously release NO, which would synergistically disrupt bacterial cell membrane, further cause leakage and damage of intracellular components, and finally induce bacteria death. On one hand, the combination of NO and PTT could largely improve the antibacterial efficiency. On the other hand, the bacterial cell membrane damage could improve the permeability and sensitivity to heat, decrease the photothermal temperature and avoid damages caused by high temperature. Moreover, TG-NO-B could be effectively utilized for synergistic therapy against the in vivo infections of MDR Gram-negative bacteria and their biofilms and accelerate wound healing as well as exhibit excellent biocompatibility both in vitro and in vivo. CONCLUSIONS: Our study demonstrates that TG-NO-B can be considered as a promising alternative for treating infections caused by MDR Gram-negative bacteria and their biofilms.
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Biofilmes/efeitos da radiação , Farmacorresistência Bacteriana Múltipla/efeitos da radiação , Bactérias Gram-Negativas/fisiologia , Raios Infravermelhos , Óxidos de Nitrogênio/metabolismo , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/farmacologia , Biofilmes/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/patologia , Infecções por Bactérias Gram-Negativas/terapia , Infecções por Bactérias Gram-Negativas/veterinária , Grafite/química , Hemólise/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Nanoestruturas/química , Nanoestruturas/toxicidade , Fototerapia , Temperatura , Distribuição Tecidual , Cicatrização/efeitos dos fármacos , Cicatrização/efeitos da radiaçãoRESUMO
An amendment to this paper has been published and can be accessed via the original article.
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INTRODUCTION: This study aims to describe a novel minimal invasive early-onset scoliosis (EOS) growth rod concept, the Cody Bünger (CB) Concept, which combines concave interval distraction and contralateral-guided growth with apical control and to investigate the 3D deformity correction, the spinal growth, and the pulmonary development. METHOD: A series of 38 children with progressive EOS and growth potential, receiving a highly specialized surgical treatment, including primary and conversion cases. Mean age was 10.2 years (4.4-15.8) with a mean follow-up of 5.6 years, and they underwent 168/184 open/magnetic lengthening procedures. Outcomes were as follows: scoliosis, kyphosis, and lordosis angles; apical rotation; spinal length; apical translation; coronal and sagittal vertical alignment; complications; and pulmonary function in a subgroup. RESULTS: Scoliosis improved from mean 76° (46-129) to 35° (8-74) post-op and was 42° (13-83) at end of treatment. Apical rotation was reduced by 30% but was partially lost during treatment. Thoracic kyphosis initially decreased by mean 15° and was partially lost during treatment. Lordosis was largely unaltered during treatment. Mean T1-S1 height increased from 30.7 cm (22.7-39.2) to 34.6 cm (27.8-45.1) postop and further increased to 38.5 cm (30.1-48.1) during treatment. This corresponded to a T1-S1 growth rate of 12 mm/year, and positive growth rates were found in all height parameters evaluated. Frontal balance and apical translation improved, whereas sagittal balance was unaltered. Complications occurred in 22/38 patients, and 11/38 had an unintended reoperation. Pulmonary function (FVC and FEV) increased but the relative lung function was unchanged. CONCLUSION: The new growth rod concept provided 3D correction and spinal growth at complication rates comparable with other growth-friendly techniques for EOS, while pulmonary function was preserved. Single magnetic rod distraction was incorporated successfully, replacing surgical elongations.
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Cifose , Escoliose , Fusão Vertebral , Criança , Seguimentos , Humanos , Cifose/cirurgia , Pulmão/diagnóstico por imagem , Pulmão/cirurgia , Reoperação , Estudos Retrospectivos , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/cirurgia , Resultado do TratamentoRESUMO
OBJECTIVE: To understand the status of health literacy and its influencing factors among the residents in Haidian District of Beijing, and to provide references for targeted health education intervention. METHODS: A multi-staged probability proportionate to size sampling(PPS) sampling method was used to collect 7034 residents that aged 15-69 years old in Haidian District in 2018. RESULTS: The standardized rate of health literacy among the residents of Haidian District was 28. 56%. The standardized health literacy rate of basic health knowledge and concept literacy, health lifestyle and behavior literacy, basic health skill were 35. 79%, 30. 90% and 36. 39%, respectively. The standardized health literacy rate of 6 health literacy issues from high to low were safety and first aid(66. 39%), scientific health perspectives(51. 24%), infectious diseases prevention and treatment(39. 78%), health information(30. 25%), chronic disease control and prevention(13. 33%), and basic medical care(11. 23%), respectively. The result of multiple logistic regression showed that aged between 30-39 years old, female, high school education and above, the teacher, medical and government staff, staff of other institutions, staff of other enterprises, other employees and the annual income of the family>45000 RMB were protective factors for health literacy. Aged between 50-69 years old was risk factor for health literacy. CONCLUSION: The level of health literacy in Haidian District was low. Various forms of intervention activities should be carried out to improve the residents' health literacy, especially focused on health lifestyle and behavior literacy, chronic disease control and prevention and basic medical care.
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Letramento em Saúde , Adulto , Idoso , Pequim , Cidades , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
The single-step syngas-to-dimethyl ether (STD) process entails economic and technical advantages over the current industrial two-step process. Pd/ZnO-based catalysts have recently emerged as interesting alternatives to currently used Cu/ZnO/Al2 O3 catalysts, but the nature of the active site(s), the reaction mechanism, and the role of Pd and ZnO in the solid catalyst are not well established. Now, Zn-stabilized Pd colloids with a size of 2â nm served as the key building blocks for the methanol active component in bifunctional Pd/ZnO-γ-Al2 O3 catalysts. The catalysts were characterized by combining high-pressure operando X-ray absorption spectroscopy and DFT calculations. The enhanced stability, longevity, and high dimethyl ether selectivity observed makes Pd/ZnO-γ-Al2 O3 an effective alternative system for the STD process compared to Cu/ZnO/γ-Al2 O3 .
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Highly crystalline films of a silver-based coordination polymer, [Ag5(C6S6)] n (Ag-BHT, BHT = benzenehexathiol), have been prepared. The structure of Ag-BHT, solved by combining rotation electron diffraction and powder X-ray diffraction techniques, indicates that it has a lamellar structure with alternatively stacked two-dimensional Ag-S networks and layers composed of one-dimensional metal-dithiolene polymers. In addition, the polycrystalline Ag-BHT film shows high electrical conductivity of up to 250 S·cm-1 at 300 K. The ultraviolet-photoelectron spectroscopy and electronic band structure calculations reveal that this can be attributed to the partially filled valence band and the unique two-dimensional Ag-S networks.
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Backgroud/Aims: The effects of rapamycin (RPM) on wound healing have been previously studied. However, reciprocal contradictory data have been reported, and the underlying mechanism remains unclear. This study aims to uncover differential role of RPM in regulation of wound healing and explore the possible mechanism. METHODS: C57BL/6J mice and epidermal cells were treated with different doses of RPM. The wound re-epithelialization was observed by hematoxylin and eosin (HE) staining. The expression of IL-15 and IGF-1 were detected by immunohistochemistry and quantitative real-time PCR. Epidermal cell survival was determined by CCK-8 assays. Moreover, the mTORC1 and mTORC2 pathway were examined by western blot analysis. RESULTS: This study showed that differential doses of RPM could lead to separate consequences in epidermis. Histological analyses showed that low-dose RPM promoted wound healing, and enhanced the expression of IL-15 and IGF-1. Furthermore, western blot analysis showed that the effect of low-dose RPM in epidermis were not through mTORC1 pathway. Instead, activation of the Akt/mTORC2 pathway was involved in low-dose RPM-induced IL-15 and IGF-1 production in epidermis, while high-dose RPM inhibited the expression of IL-15 and IGF-1 and the activity of mTORC1 and mTORC2 pathway. CONCLUSION: This study for the first time demonstrated that RPM-mediated wound healing was dose-dependent.
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Fator de Crescimento Insulin-Like I/metabolismo , Interleucina-15/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Células Epidérmicas , Epiderme/efeitos dos fármacos , Epiderme/metabolismo , Epiderme/patologia , Imuno-Histoquímica , Fator de Crescimento Insulin-Like I/genética , Interleucina-15/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Cicatrização/efeitos dos fármacosRESUMO
BACKGROUND: Electrical burns are important causes of trauma worldwide. This study aims to analyze the clinical characteristics, wound management, and outcome of electric burns. METHODS: This retrospective study was performed at the Institute of Burn Research of the Third Military Medical University during 2013-2015. Data including the demographics, injury patterns, wound treatment, and outcomes were collected and analyzed. RESULTS: A total of 595 electrical burn patients (93.8% males) were included. The average age was 37.3 ± 14.6 y, and most patients (73.5%) were aged 19â¼50 years. Most patients (67.2%) were injured in work-related circumstances. The mean total body surface area was 8.8 ± 11.8% and most wounds (63.5%) were full-thickness burns. Operation times of high-voltage burns and current burns were higher than those of low-voltage burns and arc burns, respectively. Of the 375 operated patients, 83.2% (n = 312) underwent skin autografting and 49.3% (n = 185) required skin flap coverage. Common types of skin flaps were adjacent (50.3%), random (42.2%), and pedicle (35.7%). Amputation was performed in 107 cases (18.0%) and concentrated on the hands (43.9%) and upper limbs (39.3%). The mean length of stay was 42.9 ± 46.3 d and only one death occurred (0.2%). Current burns and higher numbers of operations were major risk factors for amputation and length of stay, respectively. CONCLUSIONS: Electrical burns mainly affected adult males with occupational exposures in China. Skin autografts and various skin flaps were commonly used for electric burn wound management. More standardized and effective strategies of treatment and prevention are still needed to decrease amputation rates.