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The cooling power of a radiative cooler is more than halved in the tropics, e.g., Singapore, because of its harsh weather conditions including high humidity (84% on average), strong downward atmospheric radiation (â¼40% higher than elsewhere), abundant rainfall, and intense solar radiation (up to 1200 W/m2 with â¼58% higher UV irradiation). So far, there has been no report of daytime radiative cooling that well achieves effective subambient cooling. Herein, through integrated passive cooling strategies in a hydrogel with desirable optofluidic properties, we demonstrate stable subambient (4-8 °C) cooling even under the strongest solar radiation in Singapore. The integrated passive cooler achieves an ultrahigh cooling power of â¼350 W/m2, 6-10 times higher than a radiative cooler in a tropical climate. An in situ study of radiative cooling with various hydration levels and ambient humidity is conducted to understand the interaction between radiation and evaporative cooling. This work provides insights for the design of an integrated cooler for various climates.
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BACKGROUND: Diabetic retinopathy (DR) is a retinal microvascular complication caused by hyperglycemia, which can lead to visual impairment or blindness. Pyroptosis is a type of inflammation-related programmed cell death, activated by caspase-1, resulting in the maturation of IL-1ß and IL-18 and the rupture of the cell membrane. RNA sequencing (RNA-seq) is a high-throughput sequencing technique that reveals the presence and quantity of RNA in the genome at a specific time point, i.e., the transcriptome. RNA-seq can analyze gene expression levels, splicing variants, mutations, fusions, editing and other post-transcriptional modifications, as well as gene expression differences between different samples or conditions. It has been widely used in biological and medical research, clinical diagnosis and new drug development. This study aimed to establish an in vitro model of diabetic retinopathy by culturing human retinal endothelial cells (HREC) with high glucose (30 mmol/L), and to detect their transcriptome expression by RNA-seq, screen for key genes related to pyroptosis, and validate the sequencing results by subsequent experiments. METHODS: We used RNA-seq to detect the transcriptome expression differences between HREC cells cultured with high glucose and control group, and identified differentially expressed genes by GO/KEGG analysis. We constructed a PPI network and determined the key genes by Cytoscape software and CytoHubba plugin. We validated the expression of related factors by Western Blot, qPCR and ELISA. RESULTS: We performed GO and KEGG analysis on the RNA-seq data and found differentially expressed genes. We used Cytoscape and CytoHubba plugin to screen out IRF1 as the key gene, and then detected the expression of IRF1 in HREC under high glucose and control group by Western Blot and qPCR. We found that the expression of Caspase-1, GSDMD and IL-1ß proteins in HREC under high glucose increased, while the expression of these proteins decreased after the inhibition of IRF1 by siRNA. ELISA showed that the secretion of IL-1ß in HREC under high glucose increased, while the inhibition of IRF1 reduced the secretion of IL-1ß. These results indicate that IRF1 plays an important role in DR, and provides a new target and strategy for the prevention and treatment of this disease.
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Retinopatía Diabética , Factor 1 Regulador del Interferón , Piroptosis , Humanos , Caspasas/metabolismo , Retinopatía Diabética/genética , Retinopatía Diabética/metabolismo , Células Endoteliales/metabolismo , Perfilación de la Expresión Génica/métodos , Glucosa/metabolismo , Factor 1 Regulador del Interferón/genética , Piroptosis/genéticaRESUMEN
AIMS: The dose-escalation phase (phase Ia study) of a novel human epidermal growth factor receptor 2 (HER2) antibody-drug conjugate (ADC) FS-1502 included a dose range from 0.1 to 3.5 mg/kg in HER2-expressing advanced malignant solid tumours. However, the defined maximum tolerated dose was not reached. This model-informed approach integrated population pharmacokinetic (PopPK) modelling and exposure-response (E-R) analysis to facilitate dose selection for phase II. METHODS: The PopPK model was constructed using PK data from 109 Chinese patients who received doses of 0.1-3.5 mg/kg FS-1502 every 3 (Q3W) or 4 weeks during a phase I dose-escalation and dose expansion trial. The structural model consisted of compartment models for FS-1502 and unconjugated monomethyl auristatin F. E-R was explored for the percentage change in tumour size, overall response rate and treatment-related adverse events. RESULTS: A semi-mechanistic 2-analyte PopPK model was developed. The FS-1502 PK data were best described by a 2-compartment PK model with parallel linear and nonlinear Michaelis-Menten eliminations. The PK of unconjugated monomethyl auristatin F was described by a 2-compartment model with first-order elimination. E-R analysis supported the clinically meaningful efficacy of FS-1502 at 2.3 mg/kg and above. However, 2.3 mg/kg Q3W was considered to have a better benefit-risk balance due to a lower incidence of safety events without a significant reduction in efficacy compared to 3.0 mg/kg Q3W. CONCLUSION: This PopPK and E-R analysis guided the recommended phase II dose selection of 2.3 mg/kg Q3W and supported body weight-based dosing for an investigational HER2 ADC FS-1502.
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Antineoplásicos , Inmunoconjugados , Neoplasias , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/inducido químicamente , Receptor ErbB-2 , Inmunoconjugados/efectos adversos , Inmunoconjugados/farmacocinéticaRESUMEN
Advancements in high-temperature thermoelectric materials have been substantial, yet identifying promising near-room-temperature candidates for efficient power generation from low-grade waste heat or thermoelectric cooling applications has become critical but proven exceedingly challenging. Bismuth oxyselenide (Bi2O2Se) emerges as an ideal candidate for near-room-temperature energy harvesting due to its low thermal conductivity, high carrier mobility and remarkable air-stability. In this study, the thermoelectric properties of few-layer Bi2O2Se over a wide temperature range (20 - 380 K) are investigated, where a charge transport mechanism transitioning from polar optical phonon (POP) to piezoelectric scattering at 140 K is observed. Moreover, the Seebeck coefficient (S) increases with temperature up to 280 K then stabilizes at ~-200 µV/K through 380 K. Bi2O2Se demonstrates high mobility (450 cm2V-1s-1) within the optimum power factor (PF) window, despite its T^(-1.25) dependence. The high mobility compensates the minor reduction in carrier density n2D hence contributes to maintain a robust electrical conductivity ~3x104 S/m. This results in a remarkable PF of 860 µW m-1K-2 at 280 K without the necessity for gating (Vg = 0 V), reflecting the innate performance of the as-grown material. These results underscore the considerable promise of Bi2O2Se for room temperature thermoelectric applications.
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The electrochemical reductive valorization of CO2, referred to as the CO2RR, is an emerging approach for the conversion of CO2-containing feeds into valuable carbonaceous fuels and chemicals, with potential contributions to carbon capture and use (CCU) for reducing greenhouse gas emissions. Copper surfaces and graphene-embedded, N-coordinated single metal atom (MNC) catalysts exhibit distinctive reactivity, attracting attention as efficient electrocatalysts for CO2RR. This review offers a comparative analysis of CO2RR on copper surfaces and MNC catalysts, highlighting their unique characteristics in terms of CO2 activation, C1/C2(+) product formation, and the competing hydrogen evolution pathway. The assessment underscores the significance of understanding structure-activity relationships to optimize catalyst design for efficient and selective CO2RR. Examining detailed reaction mechanisms and structure-selectivity patterns, the analysis explores recent insights into changes in the chemical catalyst states, atomic motif rearrangements, and fractal agglomeration, providing essential kinetic information from advanced in/ex situ microscopy/spectroscopy techniques. At the end, this review addresses future challenges and solutions related to today's disconnect between our current molecular understanding of structure-activity-selectivity relations in CO2RR and the relevant factors controlling the performance of CO2 electrolyzers over longer times, with larger electrode sizes, and at higher current densities.
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While improved activity was recently reported for bimetallic iron-metal-nitrogen-carbon (FeMNC) catalysts for the oxygen reduction reaction (ORR) in acid medium, the nature of active sites and interactions between the two metals are poorly understood. Here, FeSnNC and FeCoNC catalysts were structurally and catalytically compared to their parent FeNC and SnNC catalysts. While CO cryo-chemisorption revealed a twice lower site density of M-Nx sites for FeSnNC and FeCoNC relative to FeNC and SnNC, the mass activity of both bimetallic catalysts is 50-100% higher than that of FeNC due to a larger turnover frequency in the bimetallic catalysts. Electron microscopy and X-ray absorption spectroscopy identified the coexistence of Fe-Nx and Sn-Nx or Co-Nx sites, while no evidence was found for binuclear Fe-M-Nx sites. 57Fe Mössbauer spectroscopy revealed that the bimetallic catalysts feature a higher D1/D2 ratio of the spectral signatures assigned to two distinct Fe-Nx sites, relative to the FeNC parent catalyst. Thus, the addition of the secondary metal favored the formation of D1 sites, associated with the higher turnover frequency.
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BACKGROUND: Surgery is a common treatment strategy for patients with neurofibromatosis type 1 (NF1)-related plexiform neurofibroma (PN) and has limited efficacy. FCN-159 is a novel anti-tumorigenic drug via selective inhibition of MEK1/2. This study assesses the safety and efficacy of FCN-159 in patients with NF1-related PN. METHODS: This is a multicenter, open-label, single-arm, phase I dose-escalation study. Patients with NF1-related PN that was non-resectable or unsuitable for surgery were enrolled; they received FCN-159 monotherapy daily in 28-day cycles. RESULTS: Nineteen adults were enrolled in the study, 3 in 4 mg, 4 in 6 mg, 8 in 8 mg, and 4 in 12 mg. Among patients included in dose-limiting toxicity (DLT) analysis, DLTs (grade 3 folliculitis) were reported in 1 of 8 patients (16.7%) receiving 8 mg and 3 of 3 (100%) patients receiving 12 mg. The maximum tolerated dose was determined to be 8 mg. FCN-159-related treatment-emergent adverse events (TEAEs) were observed in 19 patients (100%); most of which were grade 1 or 2. Nine (47.4%) patients reported grade 3 study-drug-related TEAEs across all dose levels, including four experiencing paronychia and five experiencing folliculitis. Of the 16 patients analyzed, all (100%) had reduced tumor size and six (37.5%) achieved partial responses; the largest reduction in tumor size was 84.2%. The pharmacokinetic profile was approximately linear between 4 and 12 mg, and the half-life supported once daily dosing. CONCLUSIONS: FCN-159 was well tolerated up to 8 mg daily with manageable adverse events and showed promising anti-tumorigenic activity in patients with NF1-related PN, warranting further investigation in this indication. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04954001. Registered 08 July 2021.
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Neurofibroma Plexiforme , Neurofibromatosis 1 , Humanos , Adulto , Neurofibromatosis 1/tratamiento farmacológico , Neurofibromatosis 1/patología , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibroma Plexiforme/patología , Inhibidores de Proteínas Quinasas/uso terapéuticoRESUMEN
Dendritic fibrous nano silica (DFNS) represents an optimal carrier material for pesticide constituents, due to its radial accessibility channels and high specific surface area. A low-energy methodology for synthesizing DFNS at a low volume ratio of oil to water is provided by employing 1-pentanol as the oil solvent in the microemulsion synthesis system, renowned for its remarkable stability and exceptional solubility. The DFNS@KM nano-pesticide was fabricated using a diffusion supported loading (DiSupLo) method and kresoxim-methyl (KM) as the template drug. Findings from Fourier-transform infrared spectroscopy, XRD, thermogravimetric, differential thermal analysis, and Brunauer-Emmet-Teller analyzes revealed the physical adsorption of KM onto the synthesized DFNS without any chemical bonding, with KM mainly existing in an amorphous state within the channels. High-performance liquid chromatography measurements demonstrated that only the loading amount of DFNS@KM was primarily dependent on the KM to DFNS ratio, with minimal effects observed from loading temperature and time. The loading amount and encapsulation efficiency of DFNS@KM were found to be 63.09% and 84.12%, respectively. Furthermore, DFNS effectively prolonged the release of KM, with a cumulative release rate of 85.43% over 180 h. The successful loading of pesticide components into DFNS synthesized with a low oil-to-water ratio provides theoretical support for the industrialization of nano-pesticides, with significant implications for enhancing pesticide utilization, reducing pesticide dosage, augmenting agricultural efficiency, and promoting sustainable agricultural development.
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BACKGROUND: Type 2 diabetes mellitus (T2DM) is a chronic and life-threatening disease. Health-related quality of life (HRQoL) is vital for individuals with T2DM. However, little is known about the impact of psychological stability factors on HRQoL among individuals with T2DM in mainland China. METHODS: This multicenter cross-sectional study was conducted in five tertiary grade-A hospitals in Chongqing, China, from January to December 2019. A total of 385 individuals with T2DM were included by the convenient sample method. Fear of Progression (FOP) Questionnaire-short Form, Hypoglycemia Fear Survey II, diabetes-management self-efficacy scale, and EuroQol-5 Dimensions were used for data collection. RESULTS: The mean age of the 385 individuals was 57.65 (SD = 15.15) years, three-quarters of whom had a high school or above education level. The participants in our study had moderate HRQoL and were more likely to have poor scores in the pain/discomfort dimension. The FOP level was moderate on average, and 23.1% of individuals suffered from psychological dysfunction. The participants had higher levels of fear of hypoglycemia (FOH) and self-efficacy (SE). Multiple steppage-regression analysis predicted that higher levels of FOP and FOH, reduced SE, older age, longer duration since diagnosis, lower educational attainment, higher levels of HbA1c, and living with comorbid conditions were related to lower HRQoL. CONCLUSION: This study showed that the HRQoL among Chinese T2DM patients may be impaired by increased FOP and FOH, decreased SE, and poor glycemic control. In addition, as the patient's age and duration since diagnosis increase, their HRQoL further declines. We recommend improving HRQoL by encouraging individuals to attain more health education and resilience skills to enhance SE and reduce negative emotions among individuals with T2DM.
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Diabetes Mellitus Tipo 2 , Hipoglucemia , Humanos , Persona de Mediana Edad , Estudios Transversales , Pueblos del Este de Asia , Calidad de Vida , Adulto , AncianoRESUMEN
The chemical selectivity and faradaic efficiency of high-index Cu facets for the CO2 reduction reaction (CO2 RR) is investigated. More specifically, shape-controlled nanoparticles enclosed by Cu {hk0} facets are fabricated using Cu multilayer deposition at three distinct layer thicknesses on the surface facets of Au truncated ditetragonal nanoprisms (Au DTPs). Au DTPs are shapes enclosed by 12 high-index {310} facets. Facet angle analysis confirms DTP geometry. Elemental mapping analysis shows Cu surface layers are uniformly distributed on the Au {310} facets of the DTPs. The 7â nm Au@Cu DTPs high-index {hk0} facets exhibit a CH4 : CO product ratio of almost 10 : 1 compared to a 1 : 1 ratio for the reference 7â nm Au@Cu nanoparticles (NPs). Operando Fourier transform infrared spectroscopy spectra disclose reactive adsorbed *CO as the main intermediate, whereas CO stripping experiments reveal the high-index facets enhance the *CO formation followed by rapid desorption or hydrogenation.
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The efficacy of radiotherapy is significantly constricted by tumor hypoxia. To overcome this obstacle, one promising approach is to use the perfluorocarbon-based O2 carriers combined with hyperoxic respiration to relieve tumor hypoxia. However, this passively transported oxygen carrier during hyperoxic respiration is prone to cause systemic oxidative stress and toxicity, which further limits its clinical application. Herein, we fabricate O2@PFC@FHA NPs for safe and specific oxygen delivery into tumors by using the fluorinated hyaluronic acid to encapsulate O2-saturated perfluorocarbon. Due to the interaction between HA and CD44 receptors, more FHA@PFC NPs accumulated in the tumor and the O2@PFC@FHA NPs significantly relieved tumor hypoxia. Notably, RT plus O2@PFC@FHA NPs resulted in almost threefold therapeutic improvement compared with RT without obvious systemic toxicity. Therefore, the O2@FHA@PFC NPs may have great potential to enhance the therapeutic efficacy of radiotherapy in the clinic.
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Fluorocarburos , Nanopartículas , Neoplasias , Humanos , Ácido Hialurónico/uso terapéutico , Neoplasias/radioterapia , Neoplasias/tratamiento farmacológico , Oxígeno , Línea Celular TumoralRESUMEN
Cultural competency is essential for providing transcultural nursing care. This qualitative study explores nurses' experiences of providing transcultural nursing care to patients from ethnic minority in Yunnan province, China, with the aim of supplementing and enriching previous quantitative research. Yunnan is home to 25 ethnic minorities with the highest proportion (33.1%) of people from ethnic minorities in China. A descriptive qualitative method was used to describe the experiences of 12 nurses. Data were collected in October 2020 through semistructured interviews and analyzed using conventional content analysis methods. Three themes were generated, including limitations of resources to provide transcultural nursing care, challenges in providing transcultural nursing care, and concerns about the quality of nursing care. The results suggest that there is scope for improving cultural competence of nurses in Yunnan through education that would enable them to provide high-quality transcultural nursing care. Training topics could include transcultural knowledge, cultural sensitivity, minority languages, and immersive multicultural experiences. Other suggested improvements include a resource room for transcultural care, the accommodation of religious and dietary needs, and dedicated staff who lead transcultural care in hospitals.
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Enfermeras y Enfermeros , Enfermería Transcultural , China , Etnicidad , Humanos , Grupos Minoritarios , Enfermería Transcultural/educaciónRESUMEN
We report and analyze a synthetic strategy toward low-Pt platinum-nickel (Pt-Ni) alloy nanoparticle (NP) cathode catalysts for the catalytic electroreduction of molecular oxygen to water. The synthesis involves the pyrolysis and leaching of Ni-organic polymers, subsequent Pt NP deposition, followed by thermal alloying, resulting in single Ni atom site (NiNC)-supported PtNi alloy NPs at low Pt weight loadings of only 3-5â wt %. Despite low Pt weight loading, the catalysts exhibit more favorable Pt-mass activities compared to conventional 20-30â wt % benchmark PtNi catalysts. Using in situ microscopic techniques, we track and unravel the key stages of the PtNi alloy formation process directly at the atomic scale. Surprisingly, we find that carbon-encapsulated metallic Ni@C structures, rather than NiNx sites, act as the Ni source during alloy formation. Our materials concepts offer a pathway to further decrease the overall Pt content in hydrogen fuel cell cathodes.
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Electrochemical CO2 reduction is a potential approach to convert CO2 into valuable chemicals using electricity as feedstock. Abundant and affordable catalyst materials are needed to upscale this process in a sustainable manner. Nickel-nitrogen-doped carbon (Ni-N-C) is an efficient catalyst for CO2 reduction to CO, and the single-site Ni-Nx motif is believed to be the active site. However, critical metrics for its catalytic activity, such as active site density and intrinsic turnover frequency, so far lack systematic discussion. In this work, we prepared a set of covalent organic framework (COF)-derived Ni-N-C catalysts, for which the Ni-Nx content could be adjusted by the pyrolysis temperature. The combination of high-angle annular dark-field scanning transmission electron microscopy and extended X-ray absorption fine structure evidenced the presence of Ni single-sites, and quantitative X-ray photoemission addressed the relation between active site density and turnover frequency.
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BACKGROUND: Emerging evidence has linked autophagy to skin wound healing; however, the underlying cellular and molecular mechanisms remain poorly understood. The present study was designed to determine the role of autophagy in endothelial cell (EC)-mediated skin wound healing in mice. METHODS: Autophagy-related gene (Atg7) in mouse ECs was inactivated by the Cre-loxP system under the control of an EC-specific VE-Cadherin (Cdh5) promoter (Atg7EC-/- mice). Full-thickness skin wounds were created on the dorsum of wild-type (WT), Cdh5-Cre+, floxed Atg7 (Atg7F/F), and Atg7EC-/- mice. Autophagic activity was determined by autophagic flux assay in the primary culture of ECs isolated from these mice. The wound re-epithelialization and angiogenesis was examined by histological analyses. The angiogenic activity of ECs was evaluated by tube formation assay in vitro. EC proliferation was examined by a cell count CCK-8 kit. EC-originated intercellular communication with dermal fibroblasts and keratinocytes was assessed by measuring the effect of EC conditional medium on the growth of keratinocytes and fibroblasts. The levels of VEGF, EGF, bFGF in EC conditional medium were measured by ELISA. RESULTS: Autophagy deficiency in ECs markedly enhanced the re-epithelialization and the wound closure during skin wound healing. However, it has minimal impact on angiogenesis in the wounded skin. Notably, autophagy deficiency in ECs did not affect their proliferation and migration or angiogenic activity per se but enhanced the EC conditional medium-induced proliferation and migration of keratinocytes and fibroblasts. CONCLUSIONS: These results demonstrate for the first time an inhibitory role of autophagy in the EC-originated paracrine regulation of skin wound healing.
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Proteína 7 Relacionada con la Autofagia/genética , Autofagia/genética , Células Endoteliales/inmunología , Herida Quirúrgica/inmunología , Cicatrización de Heridas/inmunología , Animales , Autofagia/inmunología , Comunicación Celular/genética , Comunicación Celular/inmunología , Movimiento Celular/genética , Proliferación Celular/genética , Células Cultivadas , Medios de Cultivo Condicionados/metabolismo , Modelos Animales de Enfermedad , Endotelio Vascular/citología , Femenino , Fibroblastos , Humanos , Queratinocitos , Masculino , Ratones , Ratones Noqueados , Miocardio/citología , Neovascularización Fisiológica/genética , Neovascularización Fisiológica/inmunología , Comunicación Paracrina/genética , Comunicación Paracrina/inmunología , Cultivo Primario de Células , Piel/irrigación sanguínea , Piel/lesionesRESUMEN
This study aimed to compare the predictive value of 2009 and 2013 version of Caprini risk assessment models (RAM) for venous thromboembolism (VTE) in cancer patients by receiver operating characteristic (ROC) analysis. This retrospective study reviewed a total of 1439 VTE and 1439 non-VTE Chinese cancer inpatients. The baseline demographic data of these patients were recorded. 2009 and 2013 versions Caprini RAMs were applied, and cumulative risk scores were obtained by adding the scores of each risk factor. The specificity, sensitivity, positive predictive value and negative predictive value of these two models were analyzed. ROC curve was drawn to calculate the area under the curve (AUC) and the Youden index. Significant differences were observed in the risk factors between VTE and non-VTE Group. The specificity and negative predictive value of 2013 version were higher than those of 2009 version (P < 0.05). No significant differences were found in the sensitivity or positive predictive value between 2009 and 2013 versions of the Caprini RAM (P > 0.05). The AUC and Youden index of 2013 Caprini RAM were significantly higher than those of 2009 Caprini RAM (P < 0.001), whereas the Youden index of the 2009 Caprini RAM at critical point 4 was higher than that at critical point 3 (0.362 vs 0.067, P < 0.05). Compared with 2009 version, 2013 version of the Caprini RAM provides a more accurate and efficacious method for the risk assessment of VTE in Chinese cancer patients.
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Técnicas de Apoyo para la Decisión , Neoplasias/complicaciones , Tromboembolia Venosa/etiología , Adulto , Anciano , Pueblo Asiatico , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/diagnóstico , Neoplasias/etnología , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etnologíaRESUMEN
The direct electrochemical conversion of carbon dioxide (CO2 ) into multi-carbon (C2+ ) products still faces fundamental and technological challenges. While facet-controlled and oxide-derived Cu materials have been touted as promising catalysts, their stability has remained problematic and poorly understood. Herein we uncover changes in the chemical and morphological state of supported and unsupported Cu2 O nanocubes during operation in low-current H-Cells and in high-current gas diffusion electrodes (GDEs) using neutral pH buffer conditions. While unsupported nanocubes achieved a sustained C2+ Faradaic efficiency of around 60 % for 40â h, the dispersion on a carbon support sharply shifted the selectivity pattern towards C1 products. Operando XAS and time-resolved electron microscopy revealed the degradation of the cubic shape and, in the presence of a carbon support, the formation of small Cu-seeds during the surprisingly slow reduction of bulk Cu2 O. The initially (100)-rich facet structure has presumably no controlling role on the catalytic selectivity, whereas the oxide-derived generation of under-coordinated lattice defects, can support the high C2+ product yields.
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Nitrogen-doped carbon materials featuring atomically dispersed metal cations (M-N-C) are an emerging family of materials with potential applications for electrocatalysis. The electrocatalytic activity of M-N-C materials toward four-electron oxygen reduction reaction (ORR) to H2O is a mainstream line of research for replacing platinum-group-metal-based catalysts at the cathode of fuel cells. However, fundamental and practical aspects of their electrocatalytic activity toward two-electron ORR to H2O2, a future green "dream" process for chemical industry, remain poorly understood. Here we combined computational and experimental efforts to uncover the trends in electrochemical H2O2 production over a series of M-N-C materials (M = Mn, Fe, Co, Ni, and Cu) exclusively comprising atomically dispersed M-Nx sites from molecular first-principles to bench-scale electrolyzers operating at industrial current density. We investigated the effect of the nature of a 3d metal within a series of M-N-C catalysts on the electrocatalytic activity/selectivity for ORR (H2O2 and H2O products) and H2O2 reduction reaction (H2O2RR). Co-N-C catalyst was uncovered with outstanding H2O2 productivity considering its high ORR activity, highest H2O2 selectivity, and lowest H2O2RR activity. The activity-selectivity trend over M-N-C materials was further analyzed by density functional theory, providing molecular-scale understandings of experimental volcano trends for four- and two-electron ORR. The predicted binding energy of HO* intermediate over Co-N-C catalyst is located near the top of the volcano accounting for favorable two-electron ORR. The industrial H2O2 productivity over Co-N-C catalyst was demonstrated in a microflow cell, exhibiting an unprecedented production rate of more than 4 mol peroxide gcatalyst-1 h-1 at a current density of 50 mA cm-2.
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Magnolia sinostellata is an endemic species of Magnoliaceae that is narrowly distributed in the south of Zhejiang Province, China. To explore the genetic diversity and population structure of this endangered species, this study developed sequence tag-simple sequence repeat (EST-SSR) markers based on transcriptome data of M. sinostellata. In total, 25472 SSRs were identified among 110644 unique assembled sequences with a total of 90.83 Mb and an average frequency of 23.02%. The mononucleotide (33.53%) and dinucleotide (42.08%) motifs appeared to be the most abundant. In total, 150 potential loci were randomly selected to validate the quality of the developed SSR markers; an effective PCR rate of 32.00% and a polymorphism rate of 15.33% were obtained for these loci. After performing sequencing and cloning for validation, 23 pairs of SSR primers were retained and used to characterize the genetic diversity and population structure of M. sinostellata. Overall, 204 alleles were amplified. The results of Shannon's information index (I), heterozygosity (Ho), heterozygosity (He) and Nei's expected heterozygosity (H) indicated rich genetic diversity in M. sinostellata. However, the high inbreeding coefficient and differential coefficient suggest that serious genetic drift occurred within populations, and genetic differentiation is apparent among the populations. Consequently, although M. sinostellata has high genetic diversity among populations, it is still in a serious and dangerous condition. Habitat destruction caused by human activities is the main threat to this species, and enhancing the species abundance by adopting some conservation measures should be favourable for saving the species.
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Etiquetas de Secuencia Expresada , Perfilación de la Expresión Génica/métodos , Marcadores Genéticos , Magnolia/genética , Repeticiones de Microsatélite , Clonación Molecular , Especies en Peligro de Extinción , Regulación de la Expresión Génica de las Plantas , Variación Genética , Genética de Población , Endogamia , Filogenia , Análisis de Secuencia de ADN/métodosRESUMEN
Streptococcus iniae has caused serious harm to the fish farming industry in recent years. Vaccination is a potential approach for preventing and controlling disease, being oral vaccination the most suitable vaccination route in fish. Alginate and chitosan microspheres have been widely used as controlled release systems for oral vaccination in fish. In this study, we prepared and characterized alginate/chitosan composite microspheres encapsulating the recombinant protein serine-rich repeat (rSrr) of S. iniae. We evaluated effect of these microspheres on the immune system of channel catfish. The microsphere preparation conditions were optimized by Response Surface Method and target microspheres were obtained under 1.68% alginate (w/v), the W/O ratio 3.6:7.4 (liquid paraffin with 4% Span 80, v/v) with stirring at 1000â¯rpm, 9.64% CaCl2 (w/v) and 0.95% chitosan (w/v) with an encapsulation efficiency of 92.38%. The stability and safety of rSrr-microspheres were evaluated in vitro and in vivo, respectively. Furthermore, compared with control group, oral vaccination with rSrr-microspheres induced higher serum antibody titers, higher lysozyme activity, higher total protein and higher expression of immune-related genes, and resulted in higher relative percent survival (RPS) with the value of 60% for channel catfish against S.iniae infection. Our results thus indicate that alginate/chitosan microspheres encapsulating rSrr can be used as oral vaccine for channel catfish, providing efficient immunoprotection against S. iniae infection.