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1.
J Opt Soc Am A Opt Image Sci Vis ; 41(4): 664-673, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568666

RESUMO

This study proposes two types of composite structures based on gold nano circular and nano square rings on a gold thin film for plasmonic refractive index sensing. The finite-difference time-domain method was used for simulation and analysis. The nano square ring composite structure showed superior performance, with five surface plasmon resonance modes, and a peak sensitivity and figure of merit in a liquid environment of 1600 nm/RIU and 86R I U -1, respectively. The sensing performances of localized surface plasmon resonance modes of both structures are superior to those of the propagating surface plasmon resonance modes. The proposed composite structures can provide a reference for refractive index sensing and have broad application prospects in bio-chemistry.

2.
Anim Biosci ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38575122

RESUMO

Objective: This study aimed to investigate the effects of dietary supplementation with Agaricus blazei polysaccharide (ABP) at varying concentrations on the performance, egg quality, blood biochemistry, intestinal morphology, and microflora of quail. Methods: The study involved a total of 2,700 Korean quails, which were randomly divided into three groups. The measured variables encompassed productive performance, egg parameters, carcass parameters, serum metabolites, immune response parameters, antioxidative properties, and gut microbiome. Results: The addition of ABP did not have a significant effect on average daily feed intake. However, it was found to increase the average daily egg weight and egg production rate, reduce the feed-egg ratio. There were no significant impacts on egg quality measures such as egg shape index, egg yolk index and color, egg yolk and protein content. However, ABP supplementation significantly increased the Hough Unit (HU) (p<0.01) and decreased the rate of unqualified eggs(p<0.01). Regarding serum parameters, the inclusion led to an increase in total protein concentration(p<0.05) and a reduction in low-density lipoprotein cholesterol (LDL-C) (p<0.05). There were no significant effects observed on immune indicators such as immune globulin A (IgA) and immune globulin M (IgM). ABP supplementation increased the levels of serum antioxidant indicators, including glutathione peroxidase (GSH-Px), total superoxide dismutase (T-SOD) (p<0.05), and total antioxidant capacity colorimeter (T-AOC) (p<0.05). Furthermore, ABP supplementation significantly elevated the intramuscular fatty acid content in quail meat. Additionally, ABP supplementation demonstrated a significant improvement in the diversity of gut microbiota and induced alterations in the composition of the gut microbiota. Conclusion: The findings of this study indicate that dietary supplementation of ABP enhanced production performance and antioxidant capacity while increasing the levels of polyunsaturated fatty acids (PUFA) in quail muscle.

3.
Nat Mater ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589543

RESUMO

Unconventional 1T'-phase transition metal dichalcogenides (TMDs) have aroused tremendous research interest due to their unique phase-dependent physicochemical properties and applications. However, due to the metastable nature of 1T'-TMDs, the controlled synthesis of 1T'-TMD monolayers (MLs) with high phase purity and stability still remains a challenge. Here we report that 4H-Au nanowires (NWs), when used as templates, can induce the quasi-epitaxial growth of high-phase-purity and stable 1T'-TMD MLs, including WS2, WSe2, MoS2 and MoSe2, via a facile and rapid wet-chemical method. The as-synthesized 4H-Au@1T'-TMD core-shell NWs can be used for ultrasensitive surface-enhanced Raman scattering (SERS) detection. For instance, the 4H-Au@1T'-WS2 NWs have achieved attomole-level SERS detections of Rhodamine 6G and a variety of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins. This work provides insights into the preparation of high-phase-purity and stable 1T'-TMD MLs on metal substrates or templates, showing great potential in various promising applications.

4.
J Sci Food Agric ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597278

RESUMO

BACKGROUND: Browning is the key problem hindering the industrialization of pear wine. The use of high-yield glutathione Saccharomyces cerevisiae in the fermentation of pear wine can inhibit browning. Glutathione reductase (GR) can ensure the reduction of glutathione. Spore immobilization of enzymes is a new technology. It is a new attempt to apply spore-immobilized GR in combination with high-yield glutathione S. cerevisiae to inhibit browning of pear wine. RESULTS: Saccharomyces cerevisiae spore immobilization enzyme technology was used to immobilize GR in the spores of mutant S. cerevisiae dit1∆, osw2∆ and chs3∆ and wild-type S. cerevisiae. The enzyme activity of GR immobilized by chs3∆ spores was the highest of 3.08 U mg-1 min-1. The chs3∆ spore-immobilized GR had certain resistance to ethanol, citric acid, sucrose, glucose and proteinase K. Electron microscopy analysis showed that the spore wall of chs3∆ had moderate size holes, which might be the main reason why it immobilized GR with the highest enzyme activity. And the GR was immobilized between the prespore membrane and mannoprotein layer of the spore wall. When chs3∆ spore-immobilized GR (chs3∆-GR) was added to Dangshan pear wine fermented by high-yield glutathione S. cerevisiae JN32-9, the presence of chs3∆-GR could further protect amino acids, polyphenols and glucose from oxidation, thereby reducing the browning of the pear wine during storage by 47.32%. CONCLUSION: GR immobilized by S. cerevisiae spores was effective in inhibiting the browning of pear wine. The method was simple, green and effective and did not increase the production cost of pear wine. © 2024 Society of Chemical Industry.

5.
Medicine (Baltimore) ; 103(14): e37501, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579097

RESUMO

INTRODUCTION: The efficacy of sacubitril/valsartan versus olmesartan remains controversial for the control of hypertension. We conduct a systematic review and meta-analysis to explore the influence of sacubitril/valsartan versus olmesartan on the control of hypertension. METHODS: We have searched PubMed, Embase, Web of science, EBSCO, and Cochrane library databases through July 2023 for randomized controlled trials assessing the effect of sacubitril/valsartan versus olmesartan on the control of hypertension. This meta-analysis is performed using the random-effect model or fixed-effect model based on the heterogeneity. RESULTS: Seven randomized controlled trials and 3677 patients were included in the meta-analysis. Overall, compared with olmesartan treatment for hypertension, sacubitril/valsartan treatment was associated with substantially decreased systolic blood pressure (mean difference [MD] = -4.58; 95% confidence interval [CI] = -7.90 to -1.25; P = .007), diastolic blood pressure (MD = -1.70; 95% CI = -3.24 to -0.17; P = .03), and pulse pressure (MD = -2.31; 95% CI = -4.41 to -0.21; P = .03), as well as improved systolic blood pressure control (odds ratio [OR] = 1.65; 95% CI = 1.15 to 2.38; P = .006), but had no influence on diastolic blood pressure control (OR = 1.33; 95% CI = 0.93 to 1.88; P = .11) or adverse events (OR = 1.06; 95% CI = 0.90 to 1.24; P = .51). CONCLUSIONS: Sacubitril/valsartan is better than olmesartan for the reduction of blood pressure for patients with hypertension.


Assuntos
Aminobutiratos , Hipertensão , Imidazóis , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Valsartana/efeitos adversos , Tetrazóis/uso terapêutico , Compostos de Bifenilo , Combinação de Medicamentos
6.
Sci Total Environ ; 927: 172078, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582109

RESUMO

Archaea play a crucial role in microbial systems, including driving biochemical reactions and affecting host health by producing methane through hydrogen. The study of swine gut archaea has a positive significance in reducing methane emissions and improving feed utilization efficiency. However, the development and functional changes of archaea in the pig intestines have been overlooked for a long time. In this study, 54 fecal samples were collected from 36 parental pigs (18 boars and 18 pregnant/lactating sows), and 108 fecal samples from 18 offspring pigs during lactation, nursery, growing, and finishing stages were tracked and collected for metagenomic sequencing. We obtained 14 archaeal non-redundant metagenome-assembled genomes (MAGs). These archaea were classified as Methanobacteriota and Thermoplasmatota at the phylum level, and Methanobrevibacter, Methanosphaera, MX-02, and UBA71 at the genus level, involving hydrogenotrophic, methylotrophic, and acetoclastic pathways. The hydrogenotrophic pathway dominated the methanogenesis function, and the vast majority of archaea participated in it. Dietary changes profoundly affected the archaeal composition and methanogenesis function in pigs. The abundance of hydrogen-producing bacteria in parental pigs fed high-fiber diets was higher than that in offspring pigs fed low-fiber diets. The methanogenesis function was positively correlated with fiber decomposition functions and negatively correlated with the starch decomposition function. Increased abundance of sulfate reductase and fumarate reductase, as well as decreased acetate/propionate ratio, indicated that the upregulation of alternative hydrogen uptake pathways competing with methanogens may be the reason for the reduced methanogenesis function. These findings contribute to providing information and direction in the pig industry for the development of strategies to reduce methane emissions, improve feed efficiency, and maintain intestinal health.


Assuntos
Archaea , Metano , Animais , Metano/metabolismo , Archaea/genética , Suínos , Fezes/microbiologia , Microbioma Gastrointestinal , Ração Animal/análise , Dieta/veterinária , Feminino , Metagenoma
7.
Front Neurosci ; 18: 1377094, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638698

RESUMO

Objectives: To assess the effect of total sleep deprivation (TSD) on spontaneous brain activity in medical staff during routine clinical practice. Methods: A total of 36 medical staff members underwent resting-state functional MRI (rs-fMRI) scans and neuropsychological tests twice, corresponding to rested wakefulness (RW) after normal sleep and 24 h of acute TSD. The rs-fMRI features, including the mean fractional amplitude of low-frequency fluctuation (mfALFF), z-score transformed regional homogeneity (zReHo), and functional connectivity (zFC), were compared between RW and TSD. Correlation coefficients between the change in altered rs-fMRI features and the change in altered scores of neuropsychological tests after TSD were calculated. Receiver operating characteristic (ROC) and logistic regression analyses were performed to evaluate the diagnostic efficacy of significantly altered rs-fMRI features in distinguishing between RW and TSD states. Results: Brain regions, including right superior temporal gyrus, bilateral postcentral gyrus, left medial superior frontal gyrus, left middle temporal gyrus, right precentral gyrus, and left precuneus, showed significantly enhanced rs-fMRI features (mfALFF, zReHo, zFC) after TSD. Moreover, the changes in altered rs-fMRI features of the right superior temporal gyrus, bilateral postcentral gyrus, left middle temporal gyrus, and left precuneus were significantly correlated with the changes in several altered scores of neuropsychological tests. The combination of mfALFF (bilateral postcentral gyrus) and zFC (left medial superior frontal gyrus and left precuneus) showed the highest area under the curve (0.870) in distinguishing RW from TSD. Conclusion: Spontaneous brain activity alterations occurred after TSD in routine clinical practice, which might explain the reduced performances of these participants in neurocognitive tests after TSD. These alterations might be potential imaging biomarkers for assessing the impact of TSD and distinguishing between RW and TSD states.

8.
Biochem Biophys Res Commun ; 712-713: 149923, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38640735

RESUMO

Stasimon/Tmem41b is a transmembrane protein with phospholipid scrambling activity that resides in the endoplasmic reticulum and has been implicated in autophagy, lipid metabolism, and viral replication. Stasimon/Tmem41b has also been linked to the function of sensory-motor circuits and the pathogenesis of spinal muscular atrophy. However, the early embryonic lethality of constitutive knockout in mice has hindered the analysis of spatial and temporal requirements of Stasimon/Tmem41b in vivo. To address this, we developed a novel mouse line harboring a conditional knockout allele of the Stasimon/Tmem41b gene in which exon 4 has been flanked by loxP sites (Stas/Tmem41bCKO). Cre-mediated recombination of Stas/Tmem41bCKO generates a functionally null allele (Stas/Tmem41bΔ4) resulting in loss of protein expression and embryonic lethality in the homozygous mouse mutant. Here, using a ubiquitously expressed, tamoxifen inducible Cre recombinase in the homozygous Stas/Tmem41bCKO mice, we demonstrate that postnatal depletion of Stasimon/Tmem41b rapidly arrests weight gain in adult mice and causes motor dysfunction and death approximately three weeks after tamoxifen treatment. Moreover, we show that depletion of Stasimon/Tmem41b severely affects cell proliferation in mouse embryonic fibroblasts. This study provides new insights into the essential requirement of Stasimon/Tmem41b for cellular and organismal fitness and expands the experimental toolkit to investigate its functions in the mammalian system.

10.
Front Med (Lausanne) ; 11: 1357077, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38654837

RESUMO

Objectives: This study aimed to evaluate the screening performance of COPD-PS questionnaire, COPD-SQ questionnaire, peak expiratory flow (PEF), COPD-PS questionnaire combined with PEF, and COPD-SQ questionnaire combined with PEF for chronic obstructive pulmonary disease (COPD). Methods: This was a cross-sectional study. We distributed self-designed surveys and COPD screening scales (COPD-PS questionnaire and COPD-SQ questionnaire) to residents who underwent physical examination in five community health centers in Haicang District, Xiamen City, from February 2023 to May 2023, and measured their lung function and PEF with a portable device. We used logistic regression to obtain the coefficients of COPD-PS questionnaire, COPD-SQ questionnaire, and PEF, and plotted the receiver operating characteristic curves of each tool for diagnosing COPD and moderate-to-severe COPD. We evaluated and compared the optimal cut-off points and scores of sensitivity, specificity, Youden index, and area under the curve (AUC) values, and assessed the screening efficiency of different methods. Results: Of the 3,537 residents who completed the COPD-SQ questionnaire, COPD-PS questionnaire, and spirometry, 840 were diagnosed with COPD. We obtained the coefficients of COPD-PS questionnaire combined with peak expiratory flow (PEF), and COPD-SQ questionnaire combined with PEF, by logistic regression as -0.479-0.358 × PEF +0.321 × COPD-PS score and - 1.286-0.315 × PEF +0.125 × COPD-SQ score, respectively. The sensitivity of diagnosing COPD by COPD-SQ questionnaire, COPD-PS questionnaire, PEF, COPD-PS questionnaire combined with PEF, and COPD-SQ questionnaire combined with PEF were 0.439, 0.586, 0.519, 0.586, 0.612 respectively, and the specificity were 0.725, 0.621, 0.688, 0.689, 0.663 respectively, with ROC values of 0.606 (95%CI: 0.586-0.626), 0.640 (0.619-0.661), 0.641 (0.619-0.663), 0.678 (0.657-0.699), 0.685 (0.664-0.706) respectively. The sensitivity of diagnosing GOLD II and above by COPD-SQ questionnaire, COPD-PS questionnaire, PEF, COPD-PS questionnaire combined with PEF, and COPD-SQ questionnaire combined with PEF were 0.489, 0.620, 0.665, 0.630, 0.781 respectively, and the specificity were 0.714, 0.603, 0.700, 0.811, 0.629 respectively, with ROC values of 0.631 (95%CI: 0.606-0.655), 0.653 (0.626-0.679), 0.753 (0.730-0.777), 0.784 (0.762-0.806), 0.766 (0.744-0.789) respectively. Conclusion: Our study found that the accuracy of COPD screening by COPD-SQ questionnaire and COPD-PS questionnaire can be improved by combining the results of PEF. The screening performance of COPD-SQ questionnaire combined with PEF is relatively better. In future research, further studies are needed to optimize the performance of screening tools and understand whether their use will affect clinical outcomes.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38626346

RESUMO

Background: The incidence of chronic obstructive pulmonary disease (COPD) and osteoporosis are rising worldwide. Observational studies showed that COPD is associated with increased risk of osteoporosis. We performed the Mendelian randomization (MR) study to genetically investigate the causality of COPD on osteoporosis. Methods: We explored the causal effect of COPD on osteoporosis by the MR analysis. A total of 108 genetic loci single nucleotide polymorphisms were related to COPD. The primary approach in this MR analysis was the inverse variance-weighted (IVW) method. Simple median, weighted median, MR Egger and penalized weighted median analyzed the sensitivity. Results: The study found that genetically predicted COPD is causally linked to an increased risk of osteoporosis, as evidenced by both the fixed-effect IVW model and random-effect IVW model (odds ratio [OR], 1.010; 95% CI, 1.001-1.019, P=0.021; OR, 1.010; 95% CI, 1.001-1.020, P=0.039). This association was also observed in other methods, including the simple median, weighted median, Penalised weighted median, MR-Egger method, and MR Egger (bootstrap) method. The results of the IVW and MR-Egger analyses showed no heterogeneity (Q=131.374, P=0.061 and Q=128.895, P=0.069, respectively). Additionally, MR-Egger regression did not reveal any pleiotropic influence through genetic variants (intercept, -0.004; P=0.101). Lastly, the leave-one-out sensitivity analysis did not identify any individual SNP that significantly influenced the association between COPD and osteoporosis. Conclusion: The Mendelian randomization analysis showed a significant detrimental effect of COPD on the risk of osteoporosis.

12.
Nat Commun ; 15(1): 2390, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493199

RESUMO

Metal-halide perovskite thin monocrystals featuring efficient carrier collection and transport capabilities are well suited for radiation detectors, yet their growth in a generic, well-controlled manner remains challenging. Here, we reveal that mass transfer is one major limiting factor during solution growth of perovskite thin monocrystals. A general approach is developed to overcome synthetic limitation by using a high solute flux system, in which mass diffusion coefficient is improved from 1.7×10-10 to 5.4×10-10 m2 s-1 by suppressing monomer aggregation. The generality of this approach is validated by the synthesis of 29 types of perovskite thin monocrystals at 40-90 °C with the growth velocity up to 27.2 µm min-1. The as-grown perovskite monocrystals deliver a high X-ray sensitivity of 1.74×105 µC Gy-1 cm-2 without applied bias. The findings regarding limited mass transfer and high-flux crystallization are crucial towards advancing the preparation and application of perovskite thin monocrystals.

13.
J Clin Pharmacol ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515275

RESUMO

Pathologic elevations in hepcidin, a key regulator of iron homeostasis, contribute to anemia of inflammation in chronic disease. DISC-0974 is a monoclonal antibody that binds to hemojuvelin and blocks bone morphogenetic protein signaling, thereby suppressing hepcidin production. Reduction of systemic hepcidin levels is predicted to increase iron absorption and mobilize stored iron into circulation, where it may be utilized by red blood cell (RBC) precursors in the bone marrow to improve hemoglobin levels and to potentially alleviate anemia of inflammation. We conducted a first-in-human, double-blind, placebo-controlled, single-ascending dose study to evaluate safety, pharmacokinetics, and pharmacodynamics of DISC-0974 in healthy participants. Overall, 42 participants were enrolled and received a single dose of placebo or DISC-0974 at escalating dose levels (7-56 mg), administered intravenously (IV) or subcutaneously (SC). DISC-0974 was well tolerated, with a safety profile comparable to that of placebo. Pharmacokinetic data was dose and route related, with a terminal half-life of approximately 7 days. The bioavailability of SC dosing was ∼50%. Pharmacodynamic data showed dose-dependent decreases in serum hepcidin, with reductions of nearly 75% relative to baseline at the highest dose level tested, and corresponding increases in serum iron in response to DISC-0974 administration. Dose-dependent changes in serum ferritin and hematology parameters were also observed, indicating mobilization of iron stores and downstream effects of enhanced hemoglobinization and production of RBCs. Altogether, these data are consistent with the mechanism of action of DISC-0974 and support the selection of a biologically active dose range for evaluation in clinical trials for individuals with anemia of inflammation.

14.
Cell Discov ; 10(1): 36, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38548762

RESUMO

Internal N6-methyladenosine (m6A) modifications are among the most abundant modifications of messenger RNA, playing a critical role in diverse biological and pathological processes. However, the functional role and regulatory mechanism of m6A modifications in the immune response to Mycobacterium tuberculosis infection remains unknown. Here, we report that methyltransferase-like 14 (METTL14)-dependent m6A methylation of NAPDH oxidase 2 (Nox2) mRNA was crucial for the host immune defense against M. tuberculosis infection and that M. tuberculosis-secreted antigen EsxB (Rv3874) inhibited METTL14-dependent m6A methylation of Nox2 mRNA. Mechanistically, EsxB interacted with p38 MAP kinase and disrupted the association of TAB1 with p38, thus inhibiting the TAB1-mediated autophosphorylation of p38. Interaction of EsxB with p38 also impeded the binding of p38 with METTL14, thereby inhibiting the p38-mediated phosphorylation of METTL14 at Thr72. Inhibition of p38 by EsxB restrained liquid-liquid phase separation (LLPS) of METTL14 and its subsequent interaction with METTL3, preventing the m6A modification of Nox2 mRNA and its association with the m6A-binding protein IGF2BP1 to destabilize Nox2 mRNA, reduce ROS levels, and increase intracellular survival of M. tuberculosis. Moreover, deletion or mutation of the phosphorylation site on METTL14 impaired the inhibition of ROS level by EsxB and increased bacterial burden or histological damage in the lungs during infection in mice. These findings identify a previously unknown mechanism that M. tuberculosis employs to suppress host immunity, providing insights that may empower the development of effective immunomodulators that target M. tuberculosis.

15.
J Food Sci ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38551187

RESUMO

The high concentration of citric acid in lemons limits the production of lemon fruit vinegar because it inhibits the metabolism of acetic acid bacteria and reduces the utilization of raw materials. This study aimed to enhance the citric acid tolerance of Acetobacter tropicalis by using complex mutagenesis and adaptive laboratory evolution (ALE) and improving the quality of lemon fruit vinegar. After mutagenesis and ALE, A. tropicalis JY-135 grew well under 40 g/L citric acid, and it showed high physiological activity and excellent fermentation performance under high concentrations of citric acid. The survival rate and ATP content of JY-135 were 15.27 and 9.30 times higher than that of the original strain J-2736. In the fermentation of lemon fruit vinegar, the acid production and the number of aroma-active compounds were 1.61-fold and 2.17-fold than J-2736. In addition, we found that citric acid tolerance of JY-135 is related to the respiratory electron-transport chain and the tricarboxylic acid (TCA) cycle. This work is of great significance for the production of high-quality lemon fruit vinegar and the enrichment of seed resources of acetic acid bacteria.

16.
ACS Nano ; 18(13): 9403-9412, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38488193

RESUMO

Diatomic-site catalysts (DASCs) inherit the excellent performance of single-atom catalysts (SACs) by utilizing two adjacent atomic metal species to achieve functional complementarity and synergistic effects that improve the carbon dioxide reduction reaction (CO2RR) and H2 evolution reaction (HER) kinetics. Herein, we report a method to further improve the catalytic efficiency of Pt by using Pt and Ru single atoms randomly anchored on a g-C3N4 surface, yielding partial Pt-Ru dimers. The synthesized catalyst exhibits extraordinary photocatalytic activity and stability in both the CO2RR and HER processes. In-depth experimentation, the pH-dependent chemical exchange saturation transfer (CEST) imaging nuclear magnetic resonance (NMR) method, and theoretical analyses reveal that the excellent performance is attributed to orbital coupling between the Pt atoms and the neighboring Ru atoms (mainly dxy and dxz), which decreases the orbital energy levels and weakens the bond strength with intermediates, resulting in improved CO2RR and HER performance. This study successfully applies the pH-dependent CEST imaging NMR method to catalytic reactions, and CO2 adsorption is directly observed using CEST 2D imaging maps. This work presents significant potential for a variety of catalytic reaction applications by systematically designing bimetallic dimers with higher activity and stability.

17.
Chem Rev ; 124(7): 4479-4539, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38552165

RESUMO

Crystal phase, a critical structural characteristic beyond the morphology, size, dimension, facet, etc., determines the physicochemical properties of nanomaterials. As a group of layered nanomaterials with polymorphs, transition metal dichalcogenides (TMDs) have attracted intensive research attention due to their phase-dependent properties. Therefore, great efforts have been devoted to the phase engineering of TMDs to synthesize TMDs with controlled phases, especially unconventional/metastable phases, for various applications in electronics, optoelectronics, catalysis, biomedicine, energy storage and conversion, and ferroelectrics. Considering the significant progress in the synthesis and applications of TMDs, we believe that a comprehensive review on the phase engineering of TMDs is critical to promote their fundamental studies and practical applications. This Review aims to provide a comprehensive introduction and discussion on the crystal structures, synthetic strategies, and phase-dependent properties and applications of TMDs. Finally, our perspectives on the challenges and opportunities in phase engineering of TMDs will also be discussed.

18.
Sci Rep ; 14(1): 6967, 2024 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521805

RESUMO

In this study, the ecological impact of human activities and the space occupied by construction and arable land on the Tibetan Plateau were examined, focusing on changes in the net primary productivity (NPP) as a key indicator of ecological health. With the utilization of land use data and multiyear average NPP data from 2002 to 2020, we analyzed the effects of the conversion of zonal vegetation into construction and arable land on carbon sequestration and oxygen release in Chengguan District, Lhasa city. Our findings indicated a marked spatial difference in the NPP among different land types. Regarding the original zonal vegetation, the NPP ranged from 0.2 to 0.3 kg/m2. Construction land showed a decrease in the NPP, with values ranging from 0.16 to 0.26 kg/m2, suggesting a decrease in ecological productivity. Conversely, arable land exhibited an increase in the NPP, with average values exceeding 0.3 kg/m2. This increase suggested enhanced productivity, particularly in regions where the original zonal vegetation provided lower NPP values. However, this enhanced productivity may not necessarily indicate a positive ecological change. In fact, such increases could potentially disrupt the natural balance of ecosystems, leading to unforeseen ecological consequences. The original zonal vegetation, with NPP values ranging from 0.12 to 0.43 kg/m2, exhibited higher ecological stability and adaptability than the other land types. This wider NPP range emphasizes the inherent resilience of native vegetation, which could sustain diverse ecological functions under varying environmental conditions. These findings demonstrate the urgent need for sustainable land use management on the Tibetan Plateau. This study highlights the importance of considering the ecological impact of land use changes in regional development strategies, ensuring the preservation and enhancement in the unique and fragile plateau ecosystem.


Assuntos
Ecossistema , Modelos Teóricos , Humanos , Tibet , Cidades , Atividades Humanas , China , Mudança Climática
19.
Pediatr Res ; 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431664

RESUMO

BACKGROUND: Benign epilepsy with centrotemporal spikes (BECTS) is a common childhood epilepsy syndrome, accompanied by behavioral problems and cognitive impairments. Previous studies of BECTS-related brain structures applied univariate analysis and showed inconsistent results. And neurotransmitter patterns associated with brain structural alterations were still unclear. METHODS: Structural images of twenty-one drug-naïve children with BECTS and thirty-five healthy controls (HCs) were scanned. Segmented gray matter volume (GMV) images were decomposed into independent components (ICs) using the source-based morphometry method. Then spatial correlation analyses were applied to examine possible relationships between GMV changes and neurotransmitter systems. RESULTS: Compared with HCs, drug-naïve children with BECTS showed increased volume in one GMV component (IC7), including bilateral precentral gyrus, bilateral supplementary motor area, left superior frontal cortex, bilateral middle/ inferior frontal cortex and bilateral anterior/ middle cingulate cortex. A positive correlation was observed between one GMV component (IC6) and seizure frequency. There were significantly positive correlations between abnormal GMV in IC7 and serotonergic, GABAergic and glutamatergic systems. CONCLUSION: These findings provided further evidence of changed GMV in drug-naïve children with BECTS related to their behavioral problems and cognitive impairments, and associated neurotransmitters which could help to better understand neurobiological mechanisms and underlying molecular mechanisms of BECTS. IMPACT: The article provides further evidence of changed gray matter volume in drug-naïve children with BECTS related to their behavioral problems and cognitive impairments as well as associated neurotransmitters. Most literature to date has applied univariate analysis and showed inconsistent results, and neurotransmitter patterns associated with brain structural alterations were still unclear. Therefore, this article uses multivariate method and JuSpace toolbox to fill the gap. Significantly increased gray matter volume was found in drug-naïve children with BECTS compared with healthy controls. Abnormal gray matter volume was significantly correlated with clinical data and specific neurotransmitters.

20.
Angew Chem Int Ed Engl ; : e202402390, 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38523071

RESUMO

Metal-hydride-catalyzed migratory functionalization of alkenes witnessed extensive development in the past few years. However, the asymmetric version of this reaction has remained largely underdeveloped owing to the difficulty in simultaneous control of both regio- and stereoselectivity. In addition, exploring the wider alkene substrate scope to enable more synthetically valuable applications represents another challenge in this field. In this context, a nickel-catalyzed asymmetric hydrocyanation of internal alkenes involving a chain-walking process is demonstrated. The reaction exhibits excellent regio- and enantioselectivity, proceeds under mild reaction conditions, and delivers benzylic nitriles in high yields. Even α,ω-diaryl internal alkenes, which are known to be one of the most challenging substrates of this type, could be successfully converted to the desired products with good regio- and stereoselectivity by modifying the electronic and steric effects. Theoretical calculations suggest that the η3-benzyl coordination mode and the aryl substituent (3,5-(OMe)2C6H3) on the diphosphite ligand are both key factors in regulating regio- and enantioselectivity.

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