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Coordinating the interfacial interaction between Pt-based nanoparticles (NPs) and supports is a significant strategy for the modulation of d-orbital electronic configuration and the adsorption behaviors of intermediates, which is of critical importance for boosting electrocatalytic performance. Herein, we demonstrated a specific synergy effect between the ordered PtFe intermetallic and neighboring oxygen vacancies (Ov), which provides an "ensemble reaction pool" to balance the barriers of both the activity, stability, and CO poisoning issues for the methanol oxidation reaction (MOR). In our proposed "ensemble reaction pool", the deprotonation of methanol occurs on the Pt site to form the intermediate *CO, where the strain derived from the PtFe intermetallic could alter the d-orbital electronic configuration of Pt, intrinsically weakening the *CO adsorption energy, and Ov in CeO2 promote hydroxyl species (*OH) adsorption, which will react with *CO, facilitating the dissociative adsorption of *CO, thus cooperatively enhancing the performance of MOR. The X-ray absorption fine structure (XAFS) analyses reveal the electron transfer in CeO2 and then convert Ce4+ to Ce3+. The density functional theory (DFT) calculations revealed that introducing Fe induces strain could modify the d-band center of Pt, and thus lower the energy barrier of the potential-determining step. Meanwhile, the introduction of CeO2 can favor the *OH adsorption, speeding up the oxidation and removal of *CO blocked at the Pt site. Furthermore, the determined atomic arrangement and surface composition of PtFe intermetallic further guarantee the stability of MOR by suppressing less-noble metal into the electrolyte.
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Crystal structure engineering in nanoparticles has been regarded as a vital method in catalyst development and design. Herein, PtFe nanocubes, manufactured with ordered PtFe intermetallic structure and a desired facet of {202}, have been successfully prepared via the combination of selective deposition strategy and spatial barrier effect. In-situ X-ray photoelectron spectroscopy found that the growth of the high-index facet and formation of the nanocube for o-PtFe-202 materials arise from the surface Fe2+ modification stabilized effect and the selective deposition of Cl-, respectively. Moreover, density functional theory calculations and X-ray adsorption spectroscopies further proved that the improved oxygen reduction reaction activity and stability of o-PtFe-202 mainly originate from the synergistic effect of the desired high-index facet, ordered crystal structure, and resulting optimal d-band center of Pt. As expected, the o-PtFe-202 exhibits excellent mass activity (2.48 mA·ugPt-1) and specific activity (7.78 mA·cm-2), with only a 7.3% decrease in mass activity after 30 000 cycles.
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Regulating the chemical environment of materials to optimize their electronic structure, leading to the optimal adsorption energies of intermediates, is of paramount importance to improving the performance of electrocatalysts, yet remains an immense challenge. Herein, we design a harmonious axial-coordination Pt x Fe/FeN4CCl catalyst that integrates a structurally ordered PtFe intermetallic with an orbital electron-delocalization FeN4CCl support for synergistically efficient oxygen reduction catalysis. The obtained Pt2Fe/FeN4CCl with a favorable atomic arrangement and surface composition exhibits enhanced oxygen reduction reaction (ORR) intrinsic activity and durability, achieving a mass activity (MA) and specific activity (SA) of 1.637 A mgPt -1 and 2.270 mA cm-2, respectively. Detailed X-ray absorption fine spectroscopy (XAFS) further confirms the axial-coupling effect of the FeN4CCl substrate by configuring the Fe-N bond to â¼1.92 Å and the Fe-Cl bond to â¼2.06 Å. Additionally, Fourier transforms of the extended X-ray absorption fine structure (FT-EXAFS) demonstrate relatively prominent peaks at â¼1.5 Å, ascribed to the contribution of the Fe-N/Fe-Cl, further indicating the construction of the FeN4CCl moiety structure. More importantly, the electron localization function (ELF) and density functional theory (DFT) further determine an orbital electron delocalization effect due to the strong axial traction between the Cl atoms and FeN4, resulting in electron redistribution and modification of the coordination surroundings, thus optimizing the adsorption free energy of OHabs intermediates and effectively accelerating the ORR catalytic kinetic process.
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Small auxin-upregulated RNAs (SAURs), as the largest family of early auxin-responsive genes, play important roles in plant growth and development processes, such as auxin signaling and transport, hypocotyl development, and tolerance to environmental stresses. However, the functions of few SAUR genes are known in the root development of sweet potatoes. In this study, an IbSAUR36 gene was cloned and functionally analyzed. The IbSAUR36 protein was localized to the nucleus and plasma membrane. The transcriptional level of this gene was significantly higher in the pencil root and leaf.This gene was strongly induced by indole-3-acetic acid (IAA), but it was downregulated under methyl-jasmonate(MeJA) treatment. The promoter of IbSAUR36 contained the core cis-elements for phytohormone responsiveness. Promoter ß-glucuronidase (GUS) analysis in Arabidopsis showed that IbSAUR36 is highly expressed in the young tissues of plants, such as young leaves, roots, and buds. IbSAUR36-overexpressing sweet potato roots were obtained by an efficient Agrobacterium rhizogenes-mediated root transgenic system. We demonstrated that overexpression of IbSAUR36 promoted the accumulation of IAA, upregulated the genes encoding IAA synthesis and its signaling pathways, and downregulated the genes encoding lignin synthesis and JA signaling pathways. Taken together, these results show that IbSAUR36 plays an important role in adventitious root (AR) development by regulating IAA signaling, lignin synthesis, and JA signaling pathways in transgenic sweet potatoes.
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Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Ipomoea batatas , Proteínas de Plantas , Raízes de Plantas , Plantas Geneticamente Modificadas , Ipomoea batatas/genética , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Ácidos Indolacéticos/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/genética , Regiões Promotoras Genéticas , Ciclopentanos/farmacologia , Ciclopentanos/metabolismoRESUMO
Prevention of subsequent fracture is a major public health challenge in the field of osteoporosis prevention and treatment, and older women are at high risk for osteoporotic fractures. This study aimed to examine factors associated with subsequent fracture in older Chinese women with osteoporosis. We collected data on 9212 older female patients with osteoporotic fractures from 580 medical institutions in 31 provinces of China. Higher odds of subsequent fractures were associated with age of 70-79 years (OR 1.218, 95% CI 1.049-1.414), age ≥ 80 (OR 1.455, 95% CI 1.222-1.732), index fracture site was vertebrae (OR 1.472, 95% CI 1.194-1.815) and hip (OR 1.286, 95% CI 1.041-1.590), index fracture caused by fall (OR 1.822, 95% CI 1.281-2.591), strain (OR 1.587, 95% CI 1.178-2.139), no inducement (OR 1.541, 95% CI 1.043-2.277), and assessed as high risk of fracture (OR 1.865, 95% CI 1.439-2.416), BMD T-score ≤ -2.5 (OR 1.725, 95% CI 1.440-2.067), history of surgery (OR 3.941, 95% CI 3.475-4.471) and trauma (OR 8.075, 95% CI 6.941-9.395). Low risk of fall (OR 0.681, 95% CI 0.513-0.904), use of anti-osteoporosis medication (AOM, OR 0.801, 95% CI 0.693-0.926), and women who had received fall prevention health education (OR 0.583, 95% CI 0.465-0.730) associated with lower risk. The areas under the curve of the prediction model was 0.818. The sensitivity was 67.0% and the specificity was 82.0%. The prediction model showed a good ability to predict the risk of subsequent fracture in older women with osteoporotic fractures and are suitable for early self-measurement which may benefit post-fracture management.
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Fraturas por Osteoporose , Humanos , Feminino , Idoso , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Estudos Transversais , China/epidemiologia , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Densidade Óssea , Acidentes por Quedas/estatística & dados numéricos , Osteoporose/complicações , Osteoporose/epidemiologia , População do Leste AsiáticoRESUMO
Malnutrition is a highly prevalent complication in patients with traumatic brain injury (TBI), and it is closely related to the prognosis of patients. Accurate identification of patients at high risk of malnutrition is essential. Therefore, we analyzed the risk factors of malnutrition in patients with TBI and developed a model to predict the risk of malnutrition. A retrospective collection of 345 patients with TBI, and they were divided into malnutrition and comparison groups according to the occurrence of malnutrition. Univariate correlation and multifactor logistic regression analyses were performed to determine patients' malnutrition risk factors. We used univariate and logistic regression (forward stepwise method) analyses to identify significant predictors associated with malnutrition in patients with TBI and developed a predictive model for malnutrition prediction. The model's discrimination, calibration, and clinical utility were evaluated using the receiver operating characteristic (ROC) curve, calibration plots, and decision curve analysis (DCA). A total of 216 patients (62.6%) developed malnutrition. Multifactorial logistic regression analysis showed that pulmonary infection, urinary tract infection, dysphagia, application of NGT, GCS score ≤ 8, and low ADL score were independent risk factors for malnutrition in patients with TBI (P < 0.05). The area under the curve of the model was 0.947. Calibration plots showed good discrimination of model calibration. DCA showed that the column line plot models were all clinically meaningful when nutritional interventions were performed over a considerable range of threshold probabilities (0-0.98). Malnutrition is widespread in patients with TBI, and the nomogram is a good predictor of whether patients develop malnutrition.
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BACKGROUND: In the aftermath of the COVID-19 pandemic, there has been a surge in human metapneumovirus (HMPV) transmission, surpassing pre-epidemic levels. We aim to elucidate the clinical and epidemiological characteristics of HMPV infections in the post-COVID-19 pandemic era. METHODS: In this retrospective single-center study, participants diagnosed with laboratory confirmed HMPV infection through Targeted Next Generation Sequencing were included. The study encompassed individuals admitted to Henan Children's Hospital between April 29 and June 5, 2023. Demographic information, clinical records, and laboratory indicators were analyzed. RESULTS: Between April 29 and June 5, 2023, 96 pediatric patients were identified as infected with HMPV with a median age of 33.5 months (interquartile range, 12 ~ 48 months). The majority (87.5%) of infected children were under 5 years old. Notably, severe cases were statistically younger. Predominant symptoms included fever (81.3%) and cough (92.7%), with wheezing more prevalent in the severe group (56% vs 21.1%). Coinfection with other viruses was observed in 43 patients, with Epstein-Barr virus (EBV) (15.6%) or human rhinovirus A (HRV type A) (12.5%) being the most common. Human respiratory syncytial virus (HRSV) coinfection rate was significantly higher in the severe group (20% vs 1.4%). Bacterial coinfection occurred in 74 patients, with Haemophilus influenzae (Hin) and Streptococcus pneumoniae (SNP) being the most prevalent (52.1% and 41.7%, respectively). Severe patients demonstrated evidence of multi-organ damage. Noteworthy alterations included lower concentration of IL-12p70, decreased lymphocytes percentages, and elevated B lymphocyte percentages in severe cases, with statistical significance. Moreover, most laboratory indicators exhibited significant changes approximately 4 to 5 days after onset. CONCLUSIONS: Our data systemically elucidated the clinical and epidemiological characteristics of pediatric patients with HMPV infection, which might be instructive to policy development for the prevention and control of HMPV infection and might provide important clues for future HMPV research endeavors.
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COVID-19 , Metapneumovirus , Infecções por Paramyxoviridae , Humanos , China/epidemiologia , Pré-Escolar , Metapneumovirus/genética , Metapneumovirus/isolamento & purificação , Estudos Retrospectivos , Feminino , Masculino , Lactente , Infecções por Paramyxoviridae/epidemiologia , Infecções por Paramyxoviridae/virologia , COVID-19/epidemiologia , Criança , Coinfecção/epidemiologia , Coinfecção/virologia , SARS-CoV-2/genéticaRESUMO
The brain-computer interface (BCI) is a technology that involves direct communication with parts of the brain and has evolved rapidly in recent years; it has begun to be used in clinical practice, such as for patient rehabilitation. Patient electroencephalography (EEG) datasets are critical for algorithm optimization and clinical applications of BCIs but are rare at present. We collected data from 50 acute stroke patients with wireless portable saline EEG devices during the performance of two tasks: 1) imagining right-handed movements and 2) imagining left-handed movements. The dataset consists of four types of data: 1) the motor imagery instructions, 2) raw recording data, 3) pre-processed data after removing artefacts and other manipulations, and 4) patient characteristics. This is the first open dataset to address left- and right-handed motor imagery in acute stroke patients. We believe that the dataset will be very helpful for analysing brain activation and designing decoding methods that are more applicable for acute stroke patients, which will greatly facilitate research in the field of motor imagery-BCI.
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Interfaces Cérebro-Computador , Acidente Vascular Cerebral , Humanos , Algoritmos , Eletroencefalografia/métodos , Mãos/fisiologia , Movimento/fisiologiaRESUMO
China produces more than half of global vegetables with greenhouse farms contributes approximately 35 % to the country's overall vegetable supply. The average nitrogen (N) application rate of greenhouse vegetable production exceeds 2000 kg N ha-1 yr-1, considerably contributing to global agricultural GHG emissions and reactive N (Nr) losses. Optimizing the N fertilizer utilization in greenhouse vegetable production is essential for mitigating environmental pollution and promoting sustainable development nationally and globally. In this study, we estimated the N footprint (NF), social costs (SC, which includes ecosystem and human health damage costs caused by Nr losses to the environment) and net ecosystem economic income (NEEI, which balances between the fertilizers input cost, yield profit, and social costs) of different greenhouse vegetables (tomato, pakchoi, lettuce, cabbage) under farmers' practice (FP) and reduced fertilization treatment (R). Results showed that compared with FP, the NF of tomato, pakchoi, lettuce and cabbage in the R treatment decreased by 61 %, 29 %, 46 % and 36 %, respectively, and the social costs were decreased by 60 %, 48 %, 57 % and 50 %, respectively. On the regional scale, the reduction in N fertilizer use for greenhouse vegetables in Beijing only could save the fertilizer input cost by 1-5 million USD, and avoided SC would increase by 1-14 million USD. As a result, this increased the NEEI by 2-19million USD. This study has demonstrated that adopting reduced fertilization practices represents a cost-effective measure that not only ensures yields but also decrease social costs, NF, and improve the benefits to help achieve sustainable development of greenhouse vegetable production.
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Brassica , Verduras , Humanos , Ecossistema , Fertilizantes , Agricultura/métodos , Lactuca , Fertilização , Fatores Socioeconômicos , China , Nitrogênio , Solo , Óxido Nitroso/análiseRESUMO
Ammonia (NH3) emitted from concentrated animal feeding operations can cause environmental and health problems, and indirectly contribute to greenhouse gas emissions. Cattle feedlots are known to be large sources of NH3, but few studies have documented seasonal emissions from Australian feedlots. We conducted two field campaigns to measure NH3 emissions from an intensive beef cattle feedlot in southeast Australia, and these results were combined with previous measurements at the same feedlot to document seasonal variations in emissions and to derive annual feedlot emission factors (EFs). Emission rates were calculated with an inverse dispersion modelling (IDM) technique, based on NH3 concentrations measured at the feedlot with open-path lasers (OPLs). The average area emission rates in spring, summer, autumn and winter were 90.5, 167.4, 96.2 and 86.8 µg NH3 m-2 s-1 from the cattle pens, and 22.5, 18.1, 7.7 and 20.7 µg NH3 m-2 s-1 from the manure stockpile area, respectively. The total per-animal EFs ranged from 126.0 (autumn) to 190.2 g NH3 animal-1 d-1 (summer), representing a loss of 47.5-64.6% of the fed N. Seasonal variations in emissions were related to air temperature. Slight changes in crude protein content of the cattle diet may also have impacted seasonal variability. Taking seasonal variations into consideration, the average feedlot EF was 160.4 g NH3 animal-1 d-1, with 90% of the emissions coming from the cattle pens. Extrapolating the EF to all feedlot cattle in the country, the direct NH3 emissions from Australian feedlots amount to 65.2 Gg NH3 annually, or 3.7% of the national total. Our study benchmarks seasonal and annual EFs and N losses for Australian commercial feedlots, and provides a baseline for extrapolating the impacts of mitigation efforts.
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Amônia , Gases de Efeito Estufa , Animais , Bovinos , Vitória , Amônia/análise , Estações do Ano , Esterco/análiseRESUMO
Various efficient strategies have been developed to overcome the anodic electrocatalyst issue of methanol-based fuel cells owing to their complicated methanol electrooxidation mechanism. In this work, PtCo nanoparticles with adjustable compositions supported on multiwalled carbon nanotubes (Pt1Cox/MWCNTs) through the adsorbing-coating-annealing-etching route were synthesized. Compared with the Pt/C catalyst, Pt1Co3/MWCNTs exhibit better electrocatalytic MOR activity in both activity and durability. Notably, the electrochemical mass and specific activity of the as-prepared catalyst are 1.04 mA µg-1Pt and 2.18 mA cm-2, respectively, which are higher than those of the Pt/C catalyst. Moreover, the as-prepared sample revealed lower onset potential during the CO stripping test. Furthermore, the Pt1Co3/MWCNTs possess a lower current density decrease rate in chronoamperometry and cyclic durability tests. The enhancement of activity and stability of Pt1Co3/MWCNTs could be ascribed to their ordered morphological structure, the electronic interaction between MWCNTs and PtCo nanoparticles, and the suitable electronic structure effect between Pt/Co ratios. The concept of the catalyst design in this study offers a different guideline for constructing the novel methanol electrooxidation catalyst, which will accelerate the widespread fuel cell practical application.
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Introduction: The higher plant transcription factor C2H2 zinc finger protein (C2H2-ZFP) is essential for plant growth, development, and stress response. There are limited studies on C2H2-ZFP genes in sweetpotato, despite a substantial number of C2H2-ZFP genes having been systematically found in plants. Methods: In this work, 178 C2H2-ZFP genes were found in sweetpotato, distributed randomly on 15 chromosomes, and given new names according to where they were located. These members of the zinc finger gene family are separated into six branches, as shown by the phylogenetic tree. 24 tandem repeats of IbZFP genes and 46 fragment repeats were identified, and a homology study revealed that IbZFP genes linked more regions with wild relative species of sweetpotato as well as rhizome plants like potato and cassava. And we analyzed the expression patterns of IbZFP genes during the early development of sweetpotato storage roots (SRs) and salt stress using transcriptome data, and identified 44 IbZFP genes that exhibited differences in expression levels during the early expansion of sweetpotato SRs in different varieties, and 92 IbZFP genes that exhibited differences in expression levels under salt stress in salt tolerant and salt sensitive sweetpotato varieties. Additionally, we cloned six IbZFP genes in sweetpotato and analyzed their expression patterns in different tissues, their expression patterns under abiotic stress and hormone treatment, and subcellular localization. Results and discussion: The results showed that the IbZFP genes had tissue specificity in sweetpotato and were induced to varying degrees by drought and salt stress. ABA and GA3 treatments also affected the expression of the IbZFP genes. We selected IbZFP105, which showed significant differences in expression levels under salt stress and ABA treatment, to be heterologously expressed in Arabidopsis thaliana. We found that IbZFP105 OE lines exhibited higher tolerance to salt stress and ABA stress. This indicates that IbZFP105 can enhance the salt tolerance of plants. These results systematically identified the evolution and expression patterns of members of the C2H2-ZFP gene family in sweetpotato, providing a theoretical basis for studying the role of IbZFP genes in the development of sweetpotato SRs and in resistance to stress.
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OBJECTIVE: The primary objective of this study is to elucidate the molecular mechanism underlying the reversal of peritoneal fibrosis (PF) by Danshenol C, a natural compound derived from the traditional Chinese medicine Salvia miltiorrhiza. By comprehensively investigating the intricate interactions and signaling pathways involved in Danshenol C's therapeutic effects on PF, we aim to unveil novel insights into its pharmacological actions. This investigation holds the potential to revolutionize the clinical application of Salvia miltiorrhiza in traditional Chinese medicine, offering promising new avenues for the treatment of PF and paving the way for evidence-based therapeutic interventions. METHODS: Firstly, we utilized the YaTCM database to retrieve the structural formula of Danshenol C, while the SwissTargetPrediction platform facilitated the prediction of its potential drug targets. To gain insights into the genetic basis of PF, we acquired the GSE92453 dataset and GPL6480-9577 expression profile from the GEO database, followed by obtaining disease-related genes of PF from major disease databases. R software was then employed to screen for DEG associated with PF. To explore the intricate interactions between Danshenol C's active component targets, we utilized the String database and Cytoscape3.7.2 software to construct a PPI network. Further analysis in Cytoscape3.7.2 enabled the identification of core modules within the PPI network, elucidating key targets and molecular pathways critical to Danshenol C's therapeutic actions. Subsequently, we employed R to perform GO and KEGG pathway enrichment analyses, providing valuable insights into the functional implications and potential biological mechanisms of Danshenol C in the context of PF. To investigate the binding interactions between the core active components and key targets, we conducted docking studies using Chem3D, autoDock1.5.6, SYBYL2.0, and PYMOL2.4 software. We applied in vivo and in vitro experiments to prove that Danshenol C can improve PF. In order to verify the potential gene and molecular mechanism of Danshenol C to reverse PF, we used quantitative PCR, western blot, and apoptosis, ensuring robust and reliable verification of the results. RESULTS: â Wogonin, sitosterol, and Signal Transducer and Activator of Transcription 5 (STAT5) emerged as the most significant constituents among the small-molecule active compounds and gene targets investigated. â¡38 targets intersected with the disease, among which MAPK14, CASP3, MAPK8 and STAT3 may be the key targets; The results of GO and KEGG analysis showed that there was a correlation between inflammatory pathway and Apoptosis. â£Real-time PCR showed that the mRNA expressions of MAPK8 (JNK1), MAPK14 (P38) and STAT3 were significantly decreased after Danshenol C treatment (P < 0.05), while the mRNA expression of CASP3 was significantly increased (P < 0.05)â¤Western blot showed that protein expressions of CASP3 and MAPK14 were significantly increased (P < 0.05), while the expression of STAT3 and MAPK8 was decreased after Danshenol C treatment (P < 0.05). â¥There was no significant difference in flow analysis of apoptosis among groups. CONCLUSION: The findings suggest that Danshenol C may modulate crucial molecular pathways, including the MAPK, Apoptosis, Calcium signaling, JAK-STAT signaling, and TNF signaling pathways. This regulation is mediated through the modulation of core targets such as STAT3, MAPK14, MAPK8, CASP3, and others. By targeting these key molecular players, Danshenol C exhibits the potential to regulate cellular responses to chemical stress and inflammatory stimuli. The identification of these molecular targets and pathways represents a significant step forward in understanding the molecular basis of Danshenol C's therapeutic effects in PF. This preliminary exploration provides novel avenues for the development of anti-PF treatment strategies and the discovery of potential therapeutic agents. By targeting specific core targets and pathways, Danshenol C opens up new possibilities for the development of more effective and targeted drugs to combat PF. These findings have the potential to transform the landscape of PF treatment and offer valuable insights for future research and drug development endeavors.
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Proteína Quinase 14 Ativada por Mitógeno , Fibrose Peritoneal , Humanos , Caspase 3 , Apoptose , RNA MensageiroRESUMO
BACKGROUND: Due to unreasonable nitrogen (N) application and water supply, sweet potato vines tend to grow excessively. Early development of storage roots is conducive to inhibiting vine overgrowth. Hence, we investigated how N and soil moisture affect early root growth and development. RESULTS: A pot experiment was conducted using the sweet potato cultivars Jishu26 (J26, N-susceptible) and Xushu32 (X32, N-tolerant). Two N application rates of 50 (N1) and 150 mg kg- 1 (N2) and two water regimes, drought stress (DS) (W1) and normal moisture (W2), were applied to each cultivar. For J26, the lowest expansion root weight was observed in the N2W2 treatment, while for X32, the N1W2 and N2W2 treatments resulted in higher root weights compared to other treatments. The interaction between N rates and water regimes significantly affected root surface area and volume in J26. Root cross-sections revealed that N2W2 increased the percentage of root area covered by xylem vessels and decreased the amount of secondary xylem vessels (SXV) in J26. However, in X32, it increased the number of SXV. A high N rate reduced the 13 C distribution ratio in J26 expansion roots, but had no significant effect on X32. In J26, N2W2 inhibited starch synthesis in roots by downregulating the expression of AGPa, AGPb, GBSS I, and SBE I. CONCLUSION: The observed effects were more pronounced in J26. For X32, relatively high N and moisture levels did not significantly impact storage root development. Therefore, special attention should be paid to N supply and soil moisture for N-susceptible cultivars during the early growth stage.
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Ipomoea batatas , Secas , Nitrogênio , Solo , ÁguaRESUMO
BACKGROUND: The association between brain regions involved in speech production and those that play a role in speech perception is not yet fully understood. We compared speech production related brain activity with activations resulting from perceptual categorization of syllables using high field 7 Tesla functional magnetic resonance imaging (fMRI) at 1-mm isotropic voxel resolution, enabling high localization accuracy compared to previous studies. METHODS: Blood oxygenation level dependent (BOLD) signals were obtained in 20 normal hearing subjects using a simultaneous multi-slice (SMS) 7T echo-planar imaging (EPI) acquisition with whole-head coverage and 1 mm isotropic resolution. In a speech production localizer task, subjects were asked to produce a silent lip-round vowel /u/ in response to the visual cue "U" or purse their lips when they saw the cue "P". In a phoneme discrimination task, subjects were presented with pairs of syllables, which were equiprobably identical or different along an 8-step continuum between the prototypic /ba/ and /da/ sounds. After the presentation of each stimulus pair, the subjects were asked to indicate whether the two syllables they heard were identical or different by pressing one of two buttons. In a phoneme classification task, the subjects heard only one syllable and asked to indicate whether it was /ba/ or /da/. RESULTS: Univariate fMRI analyses using a parametric modulation approach suggested that left motor, premotor, and frontal cortex BOLD activations correlate with phoneme category variability in the /ba/-/da/ discrimination task. In contrast, the variability related to acoustic features of the phonemes were the highest in the right primary auditory cortex. Our multivariate pattern analysis (MVPA) suggested that left precentral/inferior frontal cortex areas, which were associated with speech production according to the localizer task, play a role also in perceptual categorization of the syllables. CONCLUSIONS: The results support the hypothesis that articulatory motor networks in the left hemisphere that are activated during speech production could also have a role in perceptual categorization of syllables. Importantly, high voxel-resolution combined with advanced coil technology allowed us to pinpoint the exact brain regions involved in both perception and production tasks.
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Plant height is one of the key agronomic traits for improving the yield of sweet potato. Phytohormones, especially gibberellins (GAs), are crucial to regulate plant height. The enzyme 9-cis-epoxycarotenoid dioxygenase (NCED) is the key enzyme for abscisic acid (ABA) biosynthesis signalling in higher plants. However, its role in regulating plant height has not been reported to date. Here, we cloned a new NCED gene, IbNCED1, from the sweet potato cultivar Jishu26. This gene encoded the 587-amino acid polypeptide containing an NCED superfamily domain. The expression level of IbNCED1 was highest in the stem and the old tissues in the in vitro-grown and field-grown Jishu26, respectively. The expression of IbNCED1 was induced by ABA and GA3. Overexpression of IbNCED1 promoted the accumulation of ABA and inhibited the content of active GA3 and plant height and affected the expression levels of genes involved in the GA metabolic pathway. Exogenous application of GA3 could rescue the dwarf phenotype. In conclusion, we suggest that IbNCED1 regulates plant height and development by controlling the ABA and GA signalling pathways in transgenic sweet potato.
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Dioxigenases , Ipomoea batatas , Oxigenases/metabolismo , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Sweet potato (Ipomoea batatas (L.) Lam.) is one of the most important crops with high storage roots yield. The formation and expansion rate of storage root (SR) plays a crucial role in the production of sweet potato. Lignin affects the SR formation; however, the molecular mechanisms of lignin in SR development have been lacking. To reveal the problem, we performed transcriptome sequencing of SR harvested at 32, 46, and 67 days after planting (DAP) to analyze two sweet potato lines, Jishu25 and Jishu29, in which SR expansion of Jishu29 was early and had a higher yield. A total of 52,137 transcripts and 21,148 unigenes were obtained after corrected with Hiseq2500 sequencing. Through the comparative analysis, 9577 unigenes were found to be differently expressed in the different stages in two cultivars. In addition, phenotypic analysis of two cultivars, combined with analysis of GO, KEGG, and WGCNA showed the regulation of lignin synthesis and related transcription factors play a crucial role in the early expansion of SR. The four key genes swbp1, swpa7, IbERF061, and IbERF109 were proved as potential candidates for regulating lignin synthesis and SR expansion in sweet potato. The data from this study provides new insights into the molecular mechanisms underlying the impact of lignin synthesis on the formation and expansion of SR in sweet potatoes and proposes several candidate genes that may affect sweet potato yield.
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Ipomoea batatas , Ipomoea batatas/genética , Transcriptoma/genética , Lignina/genética , Raízes de Plantas/genética , Perfilação da Expressão GênicaRESUMO
Evidence from clinical studies and preclinical studies supports that exercise preconditioning can not only reduce the risk of stroke but also improve brain tissue and functional outcome after stroke. It has been demonstrated that autophagy and mitochondrial dynamics are involved in ischemic stroke. However, it is still unclear whether exercise preconditioning-induced neuroprotection against stroke is associated with modulation of autophagy and mitochondrial dynamics. Although age and sex interactively affect ischemic stroke risk, incidence, and outcome, studies based on young male animals are most often used to explore the role of exercise preconditioning in the prevention of ischemic stroke. In the current study, we examined whether exercise preconditioning could modulate autophagy and mitochondrial dynamics in a brain ischemia and reperfusion (I/R) model of female aged mice. The results showed that exercise preconditioning reduced infarct volume and improved neurological deficits. Additionally, increased levels of autophagy-related proteins LC3-II/LC3-I, LC3-II, p62, Atg7, and mitophagy-related proteins Bnip3L and Parkin, as well as increased levels of mitochondrial fusion modulator Mfn2 and mitochondrial fission modulator Drp1 in the ischemic cortex of female aged mice at 12 h after I/R were present. Our results could contribute to a better understanding of exercise preconditioning-induced neuroprotection against ischemic stroke for the elderly.
Assuntos
Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Feminino , Camundongos , Masculino , Animais , Dinâmica Mitocondrial , Autofagia , Isquemia Encefálica/prevenção & controle , Córtex Cerebral/metabolismo , Lesões Encefálicas/complicações , AVC Isquêmico/complicações , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controleRESUMO
Background: Recently, students' fitness has been declining, and high physical fitness level is crucial in establishing optimal physical/mental health and academic performance. The purpose of this study was to explore the relationship between body composition and upper limb physical fitness and the specific aspects of low physical fitness level in Chinese students. Exploring the development and impact factors for upper limb physical fitness can provide a theoretical basis for the health management strategy of students. Methods: Study 1 collected data from 183 male students over 4 years and used Hierarchical Linear Model (HLM) to explore the quadratic predictive role of body composition on upper limb physical fitness. To further explored which aspects of upper limb physical fitness were affected by body composition, study 2 conducted an experimental investigation among 42 male students, comparing different kinds of upper limb physical fitness within two different body composition groups. Results: Studies found (1) from 2015 to 2018, students' Body-Mass-Index (BMI) showed an upward trend, and BMI differences were significant from year to year. While the upper limb physical fitness showed a downward trend. There were significant differences in the number of pull-outs between 2015 and 2016, 2015 and 2017, and 2015 and 2018. (2) The quadratic term of BMI could predict the upper body physical fitness in the same year and the following year. That is, when BMI was medium, the upper body fitness of the same year and the following year was the best. (3) Chinese students with excellent body composition had greater grip strength, drape height and anaerobic power than those with average body composition. Conclusion: In recent years, male students' BMI has been increasing, and the upper body physical fitness has been decreasing. Furthermore, body composition can predict the upper body mass in the same year and the second year, and male students with better body composition also had greater grip strength, drape height and anaerobic power in their upper limbs.
RESUMO
The designs of efficient and inexpensive Pt-based catalysts for methanol oxidation reaction (MOR) are essential to boost the commercialization of direct methanol fuel cells. Here, the highly catalytic performance PtFe alloys supported on multiwalled carbon nanotubes (MWCNTs) decorating nitrogen-doped carbon (NC) have been successfully prepared via co-engineering of the surface composition and electronic structure. The Pt1 Fe3 @NC/MWCNTs catalyst with moderate Fe3+ feeding content (0.86â mA/mgPt ) exhibits 2.26-fold enhancement in MOR mass activity compared to pristine Pt/C catalyst (0.38â mA/mgPt ). Furthermore, the CO oxidation initial potential of Pt1 Fe3 @NC/MWCNTs catalyst is lower relative to Pt/C catalyst (0.71â V and 0.80â V). Benefited from the optimal surface compositions, the anti-corrosion ability of MWCNT, strong electron interaction between PtFe alloys and MWCNTs and the N-doped carbon (NC) layer, the Pt1 Fe3 @NC/MWCNTs catalyst presents an improved MOR performance and anti-CO poisoning ability. This study would open up new perspective for designing efficient electrocatalysts for the DMFCs field.