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BACKGROUND: This study aims to assess the influence of early serum phosphate fluctuation on the short-term prognosis of sepsis patients. METHODS: This retrospective study used the Medical Information Mart for Intensive Care IV database to analyze serum phosphate levels in sepsis patients within 3 days of ICU admission. According to the absolute value of delta serum phosphate (the maximum value minus the minimum value of serum phosphorus measured within three days), the patients were divided into four groups, 0-1.3, 1.4-2.0, 2.1-3.1, and ≥ 3.2 mg/dl. Meanwhile, the direction of delta serum phosphate was compared. With the serum phosphate change group of 0-1.3 mg/dl as the reference group, the relationship between delta serum phosphate and in-hospital mortality and 28-day mortality was analyzed by multivariate Logistics regression analysis. RESULTS: The study involved 1375 sepsis patients. Serum phosphate changes (0-1.3, 1.4-2.0, 2.1-3.1, and ≥ 3.2 mg/dl) correlated with in-hospital and 28-day mortality variations (p = 0.005, p = 0.008). Much higher serum phosphate fluctuation elevated in-hospital and 28-day mortality. Compared to the 0-1.3 mg/dl change group, adjusted odds ratios (OR) in other groups for in-hospital mortality were 1.25 (0.86-1.81), 1.28 (0.88-1.86), and 1.63 (1.10-2.43), and for 28-day mortality were 1.21 (0.86-1.72), 1.10 (0.77-1.57), and 1.49 (1.03-2.19). Under the trend of increasing serum phosphate, the ORs of in-hospital mortality and 28-day mortality in ≥ 3.2 mg/dl group were 2.52 and 2.01, respectively. CONCLUSION: In conclude, the delta serum phosphate ≥ 3.2 mg/dl was associated with in-hospital mortality and 28-day mortality in patients with sepsis.
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Unidades de Terapia Intensiva , Sepse , Humanos , Estudos Retrospectivos , Prognóstico , Hospitais , FosfatosRESUMO
To meet the requirements for industrial water splitting to generate hydrogen, it is urgent, but still quite challenging to develop highly active and stable electrocatalysts for large-current-density hydrogen evolution reaction (HER). Herein, Ru-incorporated NiSe2 (Ru-NiSe2 ) was designed and synthesized. The introduction of Ru results in the formation of hierarchically structured Ru-NiSe2 with large electrochemical active surface area, and well-modified electronic structure. As expected, the as-fabricated Ru-NiSe2 displays impressive HER activity in 1.0â M KOH, with a low overpotential of 180.8â mV to reach the current density of 1000â mA cm-2 . Ru-NiSe2 also presents outstanding long-term stability at high current densities, owing to its high intrinsic chemical stability, and strong catalyst-support interface. Notably, when performed at a certain current density of 1000â mA cm-2 , the overpotential increase after 90â h is only 13â mV. Such excellent HER performance of Ru-NiSe2 demonstrates its great potential for practical use in industrial water splitting.
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Developing highly active and cost-effective electrocatalysts is critical for enhancing the intrinsic performance of electrocatalytic water splitting. Oxoanion-based compounds, such as phosphates and molybdates, have emerged as promising electrocatalysts owing to their advantageous properties of nontoxicity, low price, and strong water adsorption ability. However, their relatively inferior activity has impeded extensive investigation into electrochemical applications. Herein, an amorphous phosphate-adsorbed and RuNi-doped molybdate (RuNiMo-P) composite is synthesized on nickel foam (NF) support by using a simple two-step method. Significantly, an acidic solution of phosphomolybdic acid (PMo12), containing a low concentration of Ru, can etch the NF, contributing to the in situ growth of the RuNi-doped molybdate precursor. Subsequent phosphating ensures the surface formation of the amorphous phosphate layer due to abundant oxygen in the precursor. The strong structural interaction between RuNi-doped molybdate and amorphous phosphate in RuNiMo-P prompts an enhanced hydrogen evolution reaction (HER) performance, delivering an overpotential of 38 mV at a current density of -10 mA cm-2, a Tafel slope of 53 mV dec-1, and good stability in an alkaline medium. Characterizations after HER reveal that RuNi doping, partial dissolution of phosphate and molybdate species, and newly formed NiOOH nanosheets can expose active sites, facilitate charge transfer, and modify electronic structures, thereby improving the HER performance effectively.
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Urea oxidation reaction (UOR), with a low thermodynamic potential, offers great promise for replacing anodic oxygen evolution reaction of electrolysis systems such as water splitting, carbon dioxide reduction, etc., thus reducing the overall energy consumption. To promote the sluggish kinetics of UOR, highly efficient electrocatalysts are required, and Ni-based materials have been widely investigated. However, most of these reported Ni-based catalysts suffer from large overpotentials, as they generally undergo self-oxidation to form NiOOH species at high potentials, which act as catalytically active sites for UOR. Herein, Ni-doped MnO2 (Ni-MnO2) nanosheet arrays were successfully prepared on nickel foam. The as-fabricated Ni-MnO2 shows distinct UOR behavior with most of the previously reported Ni-based catalysts, as urea oxidation on Ni-MnO2 proceeds before the formation of NiOOH. Notably, a low potential of 1.388 V vs reversible hydrogen electrode was required to achieve a high current density of 100 mA cm-2 on Ni-MnO2. It is suggested that both Ni doping and nanosheet array configuration are responsible for the high UOR activities on Ni-MnO2. The introduction of Ni modifies the electronic structure of Mn atoms, and more Mn3+ species are generated in Ni-MnO2, contributing to its outstanding UOR performance.
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This study aimed to evaluate the efficacy of an intensive lifestyle modification program tailored to rural Chinese women with prior gestational diabetes mellitus compared with usual care. In a cluster randomized controlled trial, 16 towns (clusters) in two distinct rural areas in China were randomly selected (8 towns per district); and 320 women with prior gestational diabetes mellitus were recruited from these towns. With stratification for the two study districts, eight towns (160 women) were randomly assigned to the intervention group of a tailored intensive lifestyle modification program and 8 towns (160 women) to the control group. Process measures were collected on attendance, engagement, fidelity, and satisfaction. Primary efficacy outcomes included glycemic and weight-related outcomes, while secondary efficacy outcomes were behavioral outcomes and type 2 diabetes risk score, which were collected at baseline, 3-month, and 6-month follow-up. Generalized estimation equations were used to analyze the data. High attendance (72% of sessions), engagement (67% of interactive activities and group discussions), fidelity (98%), and satisfaction (92%) with the tailored intensive lifestyle modification program were achieved. There were significant reductions in fasting blood glucose, oral glucose tolerance test 2 h, waist circumference, and type 2 diabetes risk score of participants in the intervention group compared to the control group (p < .05). There was no significant intervention effect on body mass index or behavioral outcomes (p > .05). In this study, we demonstrate the successful efficacy of an Intensive Lifestyle Modification Program in reducing type 2 diabetes risk among younger women with prior gestational diabetes mellitus. This tailored program delivered by local healthcare providers is a promising approach for diabetes prevention in rural China, reducing health disparities in rural communities about diabetes prevention. Registered in the Chinese Clinical Trial Registry (ChiCTR2000037956) on 3rd Jan 2018.
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Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Glicemia , Diabetes Mellitus Tipo 2/prevenção & controle , Diabetes Gestacional/prevenção & controle , Feminino , Humanos , Estilo de Vida , Gravidez , População RuralRESUMO
Anaerobic digestion is widely considered to be a promising technology for waste activated sludge (WAS) treatment, by which sludge stabilization and resource recovery are simultaneously achieved. The poor reaction efficiency however hinders the large-scale applications of WAS anaerobic digestion technology. This study reported an efficient sludge pretreatment method by combining freezing with calcium hypochlorite (Ca(ClO)2) for enhancing the anaerobic digestion efficiency. Experimental data showed that the optimal combination was freezing at -20 °C coupled with 0.075 g/g VSS (volatile suspended solids) Ca(ClO)2, by which the maximum biomethane production of 274.4 ± 8.2 mL/g VSS was realized, 1.62 times higher than that of the control. Model-based analysis demonstrated that higher potential and rate for methane production were attained by the combined pretreatment. Mechanism analysis revealed that the extracellular polymeric substances (EPS) and microbial cells were both effectively destructed when treated by combined freezing and Ca(ClO)2, and more dissolved organics were generated in consequence. Microbial analysis demonstrated that the co-treated reactor enriched more functional microbes (such as Methanosaeta, Methanosarcina and Candidatus_Methanofastidiosum) responsible for biomethane generation than that of the control. Furthermore, the number of fecal coliform was largely reduced in co-treated reactor. As the correlation between sludge anaerobic digestion performance and numerous pretreatment parameters was systematically revealed, this study can provide important references for engineers when applying the combined freezing and Ca(ClO)2 technology in practical engineering.
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Esgotos , Eliminação de Resíduos Líquidos , Anaerobiose , Eliminação de Resíduos Líquidos/métodos , Congelamento , Metano , Reatores BiológicosRESUMO
Ultrasound plane wave imaging technology has been applied to more clinical situations than ever before because of its rapid imaging speed and stable imaging quality. Most transducers used in plane wave imaging are linear arrays, but their structures limit the application of plane wave imaging technology in some special clinical situations, especially in the endoscopic environment. In the endoscopic environment, the size of the linear array transducer is strictly miniaturized, and the imaging range is also limited to the near field. Meanwhile, the near field of a micro linear array has serious mutual interferences between elements, which is against the imaging quality of near field. Therefore, we propose a new structure of a micro ultrasound linear array for plane wave imaging. In this paper, a theoretical comparison is given through sound field and imaging simulations. On the basis of primary work and laboratory technology, micro uniform and non-uniform linear arrays were made and experimented with the phantom setting. We selected appropriate evaluation parameters to verify the imaging results. Finally, we concluded that the micro non-uniform linear array eliminated the artifacts better than the micro uniform linear array without the additional use of signal processing methods, especially for target points in the near-field. We believe this study provides a possible solution for plane wave imaging in cramped environments like endoscopy.
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Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Processamento de Sinais Assistido por Computador , Transdutores , UltrassonografiaRESUMO
AIMS: The aims of the present study were: a) to investigate the current state of postpartum glucose screening in rural China; and b) to explore the factors influencing postpartum blood glucose screening among women with prior GDM based on Andersen's behavioural model of health service use. DESIGN: A multisite, cross-sectional study design, conducted from November 2017 to January 2018. METHODS: A total of 465 women with prior GDM were included from two county-level hospitals in rural China. The potential influencing factors for postpartum blood glucose screening based on Andersen's behavioural model, including predisposing, enabling, and need factors, were collected by self-reported questionnaires. Chi-square tests and logistic regression were used to explore the influence of these factors on whether screening of blood glucose level after delivery occurred. RESULTS: The mean age of the women was 31.92 years old (SD 5.16) and the mean time after delivery was 16.73 months (SD 15.07). The postpartum glucose screening proportion was 32.7%. Women who did not have a full-time job (p= .011) (predisposing factor), had not received any treatment for GDM (p= .002), and were not informed about screening plans for diabetes by health professionals (p < .001) (enabling factor) were less likely to engage in postpartum glucose screening. The need factor, high actual risk of developing type 2 diabetes mellitus (T2DM), was not associated with postpartum blood glucose screening (p> .05). CONCLUSIONS: In rural China, most women with prior GDM were not screened for T2DM after delivery. The women with prior GDM who did not have a full-time job or had not received any prior treatment for GDM should be the target population for health education on postpartum glucose screening. IMPACT: There is a need for data on postpartum blood glucose testing rates among rural women. Future interventions aimed at increasing postpartum blood glucose screening are needed.
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Fe-N-C single-atom catalysts (SACs) exhibit high activity for oxygen reduction reaction (ORR). However, it remains controversial how the active center mediates catalysis, and the predicted potential deviates from experimental results, hindering development of ideal SACs. Here, using first-principles calculations, we present a microkinetic model for ORR on Fe-N-C SACs, disclosing a self-adjusting mechanism induced by its intrinsic intermediate. The modeling results show that the single-atom Fe site of the FeN4 center of Fe-N-C is covered with an intermediate OH* from 0.28 to 1.00 V. Remarkably, such OH* becomes part of the active moiety, Fe(OH)N4, and can optimize intermediate bindings on the Fe site, exhibiting a theoretical half-wave potential of â¼0.88 V. Partial current density analysis reveals the dominating associative path over the dissociative ones. In addition, ORR on Mn-N-C and Co-N-C SACs is unveiled. This work demonstrates the necessity of assessing the effect of intrinsic intermediates in single-atom catalysis and provides practical guidance for rational design of high-performance SACs.
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AIMS: (a) To explore the effect of perceived stress on satisfaction with quality of life (QOL) among Chinese adolescents with type 1 diabetes (T1D); and (b) to determine if coping styles and self-efficacy are mediators of the association between perceived stress and satisfaction with QOL. BACKGROUND: Adolescents with T1D experience ongoing stress related to a complex treatment regimen and live with a condition that differentiates them from their peers. It is important to know how adolescents with T1D cope with the stress and what psychosocial attributes contribute to satisfaction with QOL. DESIGN: Cross-sectional study. METHODS: Data were collected from a sample of adolescents with T1D (N = 90) who had enrolled in a randomized control trial (baseline data) and a supplemental sample of N = 59 adolescents with T1D was recruited from a diabetes clinic from January 2016 - December 2016. RESULTS: The mean age of the participants was 13.91 years (range 8-20 years), the mean diabetes duration was 4.02 years. Approximately one-quarter of the sample exceeded the criterion score for perceived stress of 26, indicating stress sufficient to have a negative impact on physical and mental health. Adolescents with increased stress reported lower satisfaction with QOL compared with adolescents with less stress. Both externalization coping and self-efficacy were the mediators of the relationship between perceived stress and satisfaction with QOL. CONCLUSIONS: Many Chinese adolescents with T1D reported elevated stress levels which was associated with decreased satisfaction with QOL. There is a need for culturally relevant interventions to improve coping by limiting the use of externalized coping styles and strengthening self-efficacy.
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Adaptação Psicológica , Diabetes Mellitus Tipo 1/psicologia , Satisfação Pessoal , Autoeficácia , Estresse Psicológico , Adolescente , Criança , China , Feminino , Humanos , Masculino , Adulto JovemRESUMO
The ultrasound endoscopic probes with very small size transducers are normally imaging by focused ultrasound beamforming technology. So the imaging frame rate is not very high, which cannot meet the needs of some clinical applications based on high imaging rate. In recent years, plane-wave ultrafast imaging technology can obtain high image frame rate and guarantee the image quality. In this paper, a plane wave ultra-fast imaging technique based on a home-made small line array ultrasound transducer is presented. Feasibility of the method is verified by simulation estimations and phantom experiments. The results show that for the small size transducer design of plane wave ultrafast imaging, it is necessary to fully consider the combination of the array element width and the number of array elements. So that a good plane wave imaging quality can be obtained. It lays a foundation for the ultra-fast imaging of plane wave in the interventional ultrasound imaging and ultrasound endoscopy.
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Transdutores , Ultrassonografia , Imagens de Fantasmas , Ultrassonografia/instrumentaçãoRESUMO
BACKGROUND: Tartary buckwheat (Fagopyrum tataricum Gaertn.) is a widely cultivated medicinal and edible crop with excellent economic and nutritional value. The development of tartary buckwheat seeds is a very complex process involving many expression-dependent physiological changes and regulation of a large number of genes and phytohormones. In recent years, the gene regulatory network governing the physiological changes occurring during seed development have received little attention. RESULTS: Here, we characterized the seed development of tartary buckwheat using light and electron microscopy and measured phytohormone and nutrient accumulation by using high performance liquid chromatography (HPLC) and by profiling the expression of key genes using RNA sequencing with the support of the tartary buckwheat genome. We first divided the development of tartary buckwheat seed into five stages that include complex changes in development, morphology, physiology and phytohormone levels. At the same time, the contents of phytohormones (gibberellin, indole-3-acetic acid, abscisic acid, and zeatin) and nutrients (rutin, starch, total proteins and soluble sugars) at five stages were determined, and their accumulation patterns in the development of tartary buckwheat seeds were analyzed. Second, gene expression patterns of tartary buckwheat samples were compared during three seed developmental stages (13, 19, and 25 days postanthesis, DPA), and 9 765 differentially expressed genes (DEGs) were identified. We analyzed the overlapping DEGs in different sample combinations and measured 665 DEGs in the three samples. Furthermore, expression patterns of DEGs related to phytohormones, flavonoids, starch, and storage proteins were analyzed. Third, we noted the correlation between the trait (physiological changes, nutrient changes) and metabolites during seed development, and discussed the key genes that might be involved in the synthesis and degradation of each of them. CONCLUSION: We provided abundant genomic resources for tartary buckwheat and Polygonaceae communities and revealed novel molecular insights into the correlations between the physiological changes and seed development of tartary buckwheat.
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Fagopyrum/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Fagopyrum/genética , Fagopyrum/fisiologia , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Reguladores de Crescimento de Plantas/metabolismo , Sementes/genéticaRESUMO
Recently, development of a new type of anode material for lithium-ion batteries that possesses multielectron reaction, sufficient charge transfer, and restricted volume suppression has been considered a huge challenge. Herein, we find a simple hot-pressing method to incorporate polyoxometalate (POM)-based metal-organic frameworks (MOFs) onto three-dimensionally structured carbon cloth (CC), denoted as HP-NENU-5/CC, which immobilizes POMs into the MOFs avoiding the leaching of POMs and employs HP-NENU-5/CC as a flexible, conductive, and porous anode material. The HP-NENU-5/CC anode materials show outstanding electrochemical performance, exhibiting high reversible capacity (1723 mAh g-1 at 200 mA g-1), high rate capability (1072 mAh g-1 at 1000 mA g-1), and superior cycling stability (1072 mAh g-1 at 1000 mA g-1 after 400 cycles). Most importantly, the performance of HP-NENU-5/CC is the best among those of all reported POMs and MOF-based materials. In addition, we perform a comparative study for active materials coated on a two-dimensional current collector and CC, and our experimental results and analysis prove that the active material coated on CC does enhance the electrochemical performance.
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BACKGROUND: In China, about 53.4 million women (11%) have type 2 diabetes (T2DM). Women with prior 2 (GDM) are at a high risk for T2DM. Postpartum lifestyle interventions have been effective in reducing T2DM for this population, but the evidence is limited to interventions provided in urban areas, despite the fact that a higher prevalence of undiagnosed T2DM was found in rural areas in China. The primary purpose of this proposed study is to examine the effect of a postpartum intensive lifestyle modification (ILSM) program on physiological health outcomes (T2DM development, insulin resistance, and weight-related variables), weight-related health behaviors (dietary intake and physical activity), and psychosocial outcomes (self-efficacy, perceived stress, social support, and health-related quality of life) compared to usual care at 3, 6, and 18 months post baseline assessment. The secondary outcomes are to identify potential mediators and moderators on change of physiological health outcomes. METHODS/DESIGN: A multi-site randomized clinical trial (RCT) will be conducted to examine the efficacy of an evidence-based Intensive Lifestyle Modification (ILSM) program compared with usual care for women with prior GDM living in rural areas in China. A total sample of 256 participants will be recruited in the study. The intervention consists of six bi-weekly in-person group sessions, five bi-weekly telephone consultation sessions, and three monthly telephone consultations to encourage behavior change. The usual care provided to the control group will utilize current clinical guideline and recommendations for T2DM prevention. Outcome measures include physiological variables (OGTT-2 h, HbA1c, weight, and waist circumference); weight-related health behavioral (dietary intake and physical activities); and psychosocial variables (self-efficacy and social support) at 3-, 6- and 18- month after baseline. We will also assess the potential cost-effectiveness of ILSM (net cost per T2DM case and per DALY averted) compared with usual care. DISCUSSION: If successful, this ILSM program can be adapted and used in rural areas as a blueprint for clinical guidelines to decrease T2DM by improving postpartum GDM care in China. Findings of this study are expected to make a significant contribution to public health practice and health policy related to T2DM prevention in China. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1800015023 . Registered 1 March 2018 - Retrospectively registered, http://apps.who.int/trialsearch/default.aspx .
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Diabetes Mellitus Tipo 2/prevenção & controle , Diabetes Gestacional/epidemiologia , Estilo de Vida , Cuidado Pós-Natal , População Rural , Adulto , China/epidemiologia , Análise Custo-Benefício , Feminino , Seguimentos , Humanos , Cuidado Pós-Natal/economia , Gravidez , Avaliação de Programas e Projetos de Saúde , Projetos de Pesquisa , População Rural/estatística & dados numéricosRESUMO
Tartary buckwheat is a type of cultivated medicinal and edible crop with good economic and nutritional value. Knowledge of the final fruit size of buckwheat is critical to its yield increase. In this study, the fruit development of two species of Tartary buckwheat in the Polygonaceae was analyzed. During fruit development, the size/weight, the contents of auxin (AUX)/abscisic acid (ABA), the number of cells, and the changes of embryo were measured and observed; and the two fruit materials were compared to determine the related mechanisms that affected fruit size and the potential factors that regulated the final fruit size. The early events during embryogenesis greatly influenced the final fruit size, and the difference in fruit growth was primarily due to the difference in the number of cells, implicating the effect of cell division rate. Based on our observations and recent reports, the balance of AUX and ABA might be the key factor that regulated the cell division rate. They induced the response of auxin response factor 2 (FtARF2) and downstream small auxin upstream RNA (FtSAURs) through hormone signaling pathway to regulate the fruit size of Tartary buckwheat. Further, through the induction of fruit expansion by exogenous auxin, FtARF2b was significantly downregulated. The FtARF2b is a potential target for molecular breeding or gene editing.
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Ácido Abscísico/metabolismo , Fagopyrum/metabolismo , Frutas/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Plantas/metabolismo , Divisão Celular/fisiologia , Polygonaceae/metabolismoRESUMO
Auxin signaling plays an important role in plant growth and development. It responds to various developmental and environmental events, such as embryogenesis, organogenesis, shoot elongation, tropical growth, lateral root formation, flower and fruit development, tissue and organ architecture, and vascular differentiation. However, there has been little research on the Auxin Response Factor (ARF) genes of tartary buckwheat (Fagopyrum tataricum), an important edible and medicinal crop. The recent publication of the whole-genome sequence of tartary buckwheat enables us to study the tissue and expression profile of the FtARF gene on a genome-wide basis. In this study, 20 ARF (FtARF) genes were identified and renamed according to the chromosomal distribution of the FtARF genes. The results showed that the FtARF genes belonged to the related sister pair, and the chromosomal map showed that the duplication of FtARFs was related to the duplication of the chromosome blocks. The duplication of some FtARF genes shows conserved intron/exon structure, which is different from other genes, suggesting that the function of these genes may be diverse. Real-time quantitative PCR analysis exhibited distinct expression patterns of FtARF genes in various tissues and in response to exogenous auxin during fruit development. In this study, 20 FtARF genes were identified, and the structure, evolution, and expression patterns of the proteins were studied. This systematic analysis laid a foundation for the further study of the functional characteristics of the ARF genes and for the improvement of tartary buckwheat crops.
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Fagopyrum/genética , Genes de Plantas , Genoma de Planta , Ácidos Indolacéticos/metabolismo , Família Multigênica , Proteínas de Plantas/genética , Cromossomos de Plantas/genética , Evolução Molecular , Fagopyrum/efeitos dos fármacos , Frutas/genética , Frutas/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/farmacologia , Motivos de Nucleotídeos/genética , Especificidade de Órgãos/genética , Filogenia , Proteínas de Plantas/metabolismo , Especificidade da Espécie , Sintenia/genéticaRESUMO
Despite wide applications of bimetallic electrocatalysis in oxygen evolution reaction (OER) owing to their superior performance, the origin of the improved performance remains elusive. The underlying mechanism was explored by designing and synthesizing a series of stable metal-organic frameworks (MOFs: NNU-21-24) based on trinuclear metal carboxylate clusters and tridentate carboxylate ligands. Among the examined stable MOFs, NNU-23 exhibits the best OER performance; particularly, compared with monometallic MOFs, all the bimetallic MOFs display improved OER activity. DFT calculations and experimental results demonstrate that introduction of the second metal atom can improve the activity of the original atom. The proposed model of bimetallic electrocatalysts affecting their OER performance can facilitate design of efficient bimetallic catalysts for energy storage and conversion, and investigation of the related catalytic mechanisms.
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A series of isoreticular metal-organic frameworks (MOFs; NENU-511-NENU-514), which all have high surface areas and strong adsorption capacities, have been successfully constructed by using mixed ligands. NENU-513 has the highest benzene capacity of 1687â mg g(-1) at 298â K, which ranks as the top MOF material among those reported up to now. This NENU series has been used for adsorptive desulfurization because of its permanent porosity. The results indicate that this series has a higher adsorptive efficiency in the removal of organosulfur compounds than other MOF materials, especially NENU-511, which has the highest adsorptive efficiency in the ambient atmosphere. This study proves that the design and synthesis of targeted MOFs with higher surface areas and with functional groups present is an efficient method to enhance benzene-storage capacity and the adsorption of organosulfur compounds.
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We have synthesized a porous Mo-based composite obtained from a polyoxometalate-based metal-organic framework and graphene oxide (POMOFs/GO) using a simple one-pot method. The MoO2 @PC-RGO hybrid material derived from the POMOFs/GO composite is prepared at a relatively low carbonization temperature, which presents a superior activity for the hydrogen-evolution reaction (HER) in acidic media owing to the synergistic effects among highly dispersive MoO2 particles, phosphorus-doped porous carbon, and RGO substrates. MoO2 @PC-RGO exhibits a very positive onset potential close to that of 20 % Pt/C, low Tafel slope of 41â mV dec(-1) , high exchange current density of 4.8×10(-4) â A cm(-2) , and remarkable long-term cycle stability. It is one of the best high-performance catalysts among the reported nonprecious metal catalysts for HER to date.
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Hidrogênio/química , Molibdênio/química , Compostos Organometálicos/química , Catálise , Compostos Organometálicos/síntese química , Tamanho da Partícula , Porosidade , Propriedades de SuperfícieRESUMO
Self-supported Ru-doped NiMoO4 (Ru-NiMoO4) is synthesized on commercial NiMo foam. The Ru-NiMoO4 exhibits extremely high performance for electrocatalytic hydrogen evolution with a small overpotential of 170.6 mV to afford a current density of 1000 mA cm-2, and excellent durability for 150 hours in alkaline solution.