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1.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35017300

RESUMEN

The Fenton-like process catalyzed by metal-free materials presents one of the most promising strategies to deal with the ever-growing environmental pollution. However, to develop improved catalysts with adequate activity, complicated preparation/modification processes and harsh conditions are always needed. Herein, we proposed an ultrafast and facile strategy to convert various inefficient commercial nanocarbons into highly active catalysts by noncovalent functionalization with polyethylenimine (PEI). The modified catalysts could be in situ fabricated by direct addition of PEI aqueous solution into the nanocarbon suspensions within 30 s and without any tedious treatment. The unexpectedly high catalytic activity is even superior to that of the single-atom catalyst and could reach as high as 400 times higher than the pristine carbon material. Theoretical and experimental results reveal that PEI creates net negative charge via intermolecular charge transfer, rendering the catalyst higher persulfate activation efficiency.

2.
Nano Lett ; 24(17): 5206-5213, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38647212

RESUMEN

Single Atoms Catalysts (SACs) have emerged as a class of highly promising heterogeneous catalysts, where the traditional bottom-up synthesis approaches often encounter considerable challenges in relation to aggregation issues and poor stability. Consequently, achieving densely dispersed atomic species in a reliable and efficient manner remains a key focus in the field. Herein, we report a new facile electrochemical knock-down strategy for the formation of SACs, whereby the metal Zn clusters are transformed into single atoms. While a defect-rich substrate plays a pivotal role in capturing and stabilizing isolated Zn atoms, the feasibility of this novel strategy is demonstrated through a comprehensive investigation, combining experimental and theoretical studies. Furthermore, when studied in exploring for potential applications, the material prepared shows a remarkable improvement of 58.21% for the Li+ storage and delivers a capacity over 300 Wh kg-1 after 500 cycles upon the transformation of Zn clusters into single atoms.

3.
BMC Plant Biol ; 24(1): 414, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760680

RESUMEN

BACKGROUND: Variations in hydraulic conductivity may arise from species-specific differences in the anatomical structure and function of the xylem, reflecting a spectrum of plant strategies along a slow-fast resource economy continuum. Spruce (Picea spp.), a widely distributed and highly adaptable tree species, is crucial in preventing soil erosion and enabling climate regulation. However, a comprehensive understanding of the variability in anatomical traits of stems and their underlying drivers in the Picea genus is currently lacking especially in a common garden. RESULTS: We assessed 19 stem economic properties and hydraulic characteristics of 17 Picea species grown in a common garden in Tianshui, Gansu Province, China. Significant interspecific differences in growth and anatomical characteristics were observed among the species. Specifically, xylem hydraulic conductivity (Ks) and hydraulic diameter exhibited a significant negative correlation with the thickness to span ratio (TSR), cell wall ratio, and tracheid density and a significant positive correlation with fiber length, and size of the radial tracheid. PCA revealed that the first two axes accounted for 64.40% of the variance, with PC1 reflecting the trade-off between hydraulic efficiency and mechanical support and PC2 representing the trade-off between high embolism resistance and strong pit flexibility. Regression analysis and structural equation modelling further confirmed that tracheid size positively influenced Ks, whereas the traits DWT, D_r, and TSR have influenced Ks indirectly. All traits failed to show significant phylogenetic associations. Pearson's correlation analysis demonstrated strong correlations between most traits and longitude, with the notable influence of the mean temperature during the driest quarter, annual precipitation, precipitation during the wettest quarter, and aridity index. CONCLUSIONS: Our results showed that xylem anatomical traits demonstrated considerable variability across phylogenies, consistent with the pattern of parallel sympatric radiation evolution and global diversity in spruce. By integrating the anatomical structure of the stem xylem as well as environmental factors of origin and evolutionary relationships, our findings provide novel insights into the ecological adaptations of the Picea genus.


Asunto(s)
Clima , Picea , Madera , Xilema , Picea/anatomía & histología , Picea/fisiología , Picea/crecimiento & desarrollo , Madera/anatomía & histología , Xilema/anatomía & histología , Xilema/fisiología , China , Especificidad de la Especie , Tallos de la Planta/anatomía & histología , Tallos de la Planta/fisiología , Tallos de la Planta/crecimiento & desarrollo
4.
BMC Plant Biol ; 24(1): 479, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816690

RESUMEN

The taxonomic classification of Picea meyeri and P. mongolica has long been controversial. To investigate the genetic relatedness, evolutionary history, and population history dynamics of these species, genotyping-by-sequencing (GBS) technology was utilized to acquire whole-genome single nucleotide polymorphism (SNP) markers, which were subsequently used to assess population structure, population dynamics, and adaptive differentiation. Phylogenetic and population structural analyses at the genomic level indicated that although the ancestor of P. mongolica was a hybrid of P. meyeri and P. koraiensis, P. mongolica is an independent Picea species. Additionally, P. mongolica is more closely related to P. meyeri than to P. koraiensis, which is consistent with its geographic distribution. There were up to eight instances of interspecific and intraspecific gene flow between P. meyeri and P. mongolica. The P. meyeri and P. mongolica effective population sizes generally decreased, and Maxent modeling revealed that from the Last Glacial Maximum (LGM) to the present, their habitat areas decreased initially and then increased. However, under future climate scenarios, the habitat areas of both species were projected to decrease, especially under high-emission scenarios, which would place P. mongolica at risk of extinction and in urgent need of protection. Local adaptation has promoted differentiation between P. meyeri and P. mongolica. Genotype‒environment association analysis revealed 96,543 SNPs associated with environmental factors, mainly related to plant adaptations to moisture and temperature. Selective sweeps revealed that the selected genes among P. meyeri, P. mongolica and P. koraiensis are primarily associated in vascular plants with flowering, fruit development, and stress resistance. This research enhances our understanding of Picea species classification and provides a basis for future genetic improvement and species conservation efforts.


Asunto(s)
Genoma de Planta , Picea , Polimorfismo de Nucleótido Simple , Dinámica Poblacional , Picea/genética , Filogenia , Flujo Génico , Adaptación Fisiológica/genética , Ecosistema
5.
BMC Plant Biol ; 24(1): 217, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38532319

RESUMEN

Catalpa bungei is a precious timber species distributed in North China where drought often occurs. To clarify adaptive responses of C. bungei to partial- and full- root-zone drought under the influence of nitrogen forms, a two-factor experiment was conducted in which well-watered (WW), partial root-zone drought in horizontal direction (H-PRD) and in vertical direction (V-PRD), and full root-zone drought (FRD) were combined with nitrate-nitrogen (NN) and ammonium-nitrogen (AN) treatments. C. bungei responded to FRD by sharply closing stomata, decreasing gas exchange rate and increasing leaf instantaneous water use efficiency (WUEi). Under FRD condition, the growth of seedlings was severely inhibited and the effect of N forms was covered up by the drastic drought effect. In comparison, stomata conductance and gas exchanges were moderately inhibited by PRDs. WUEi in V-PRD treatment was superior to H-PRD due to the active stomata regulation resulting from a higher ABA level and active transcription of genes in abscisic acid (ABA) signaling pathway under V-PRD. Under both PRDs and FRD, nitrate benefited antioxidant defense, stomata regulation and leaf WUEi. Under V-PRD, WUEi in nitrate treatment was superior to that in ammonium treatment due to active stomata regulation by signaling network of nitric oxide (NO), Ca2+ and ABA. Under FRD, WUEi was higher in nitrate treatment due to the favoring photosynthetic efficiency resulting from active NO signal and antioxidant defense. The interactive effect of water and N forms was significant on wood xylem development. Superoxide dismutase (SOD) and catalase (CAT) largely contributes to stress tolerance and xylem development.


Asunto(s)
Nitratos , Nitrógeno , Nitrógeno/metabolismo , Sequías , Antioxidantes , Agua/metabolismo
6.
Small ; 20(25): e2309427, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38240468

RESUMEN

As cost-effective catalysts, platinum (Pt) single-atom catalysts (SACs) have attracted substantial attention. However, most studies indicate that Pt SACs in acidic hydrogen evolution reaction (HER) follow the slow Volmer-Heyrovsky (VH) mechanism instead of the fast kinetic Volmer-Tafel (VT) pathway. Here, this work propose that the VH mechanism in Pt SACs can be switched to the faster VT pathway for efficient HER by correlating Pt single atoms (SAs) with Pt clusters (Cs). Our calculations reveal that the correlation between Pt SAs and Cs significantly impacts the electronic structure of exposed Pt atoms, lowering the adsorption barrier for atomic hydrogen and enabling a faster VT mechanism. To validate these findings, this work purposely synthesize three catalysts: l-Pt@MoS2, m-Pt@MoS2 and h-Pt@MoS2 with low, moderate, and high Pt-loading, having different distributions of Pt SAs and Cs. The m-Pt@MoS2 catalyst with properly correlating Pt SAs and Cs exhibits outstanding performance with an overpotential of 47 mV and Tafel slope of 32 mV dec-1. Further analysis of the Tafel values confirms that the m-Pt@MoS2 sample indeed follows the VT reaction mechanism, aligning with the theoretical findings. This study offers a deep understanding of the synergistic mechanism, paving a way for designing novel-advanced catalysts.

7.
Small ; 20(12): e2307902, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37950404

RESUMEN

A rational design of sulfur host is the key to conquering the"polysulfide shuttle effects" by accelerating the polysulfide conversion. Since the process involves solid-liquid-solid multistep phase transitions, purposely-engineered heterostructure catalysts with various active regions for catalyzing conversion steps correspondingly are beneficial to promote the overall conversion process. However, the functionalities of the materials surface and interface in heterostructure catalysts remain unclear. In this work, an Mo2C/MoC catalyst with abundant Mo2C surface-interface-MoC surface tri-active-region is developed by in situ converting the MoZn-metal organic framework. The experimental and simulation studies demonstrate the interface can catch long-chain polysulfides and promote their conversion. Instead, the Mo2C and MoC tend to accommodate the short-chain polysulfide and accelerate their conversion and the Li2S dissociation. Benefitting from the high catalytic ability, the Li-S battery assembled with the Mo2C/MoC-S cathode shows more discrete redox reactions and delivers a high initial capacity of 1603.6 mAh g-1 at 1 C charging-discharging rate, which is over twofolds of the one assembled using individual hosts, and 80.4% capacity can be maintained after 1000 cycles at 3 C rate. This work has demonstrated a novel synergy between the interface and material surface, which will help the future design of high-performance Li-S batteries.

8.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-34810250

RESUMEN

Arising from reduced dielectric screening, excitonic effects should be taken into account in ultrathin two-dimensional photocatalysts, and a significant challenge is achieving nontrivial excitonic regulation. However, the effect of structural modification on the regulation of the excitonic aspect is at a comparatively early stage. Herein, we report unusual effects of surface substitutional doping with Pt on electronic and surface characteristics of atomically thin layers of Bi3O4Br, thereby enhancing the propensity to generate 1O2 Electronically, the introduced Pt impurity states with a lower energy level can trap photoinduced singlet excitons, thus reducing the singlet-triplet energy gap by ∼48% and effectively facilitating the intersystem crossing process for efficient triplet excitons yield. Superficially, the chemisorption state of O2 causes the changes in the magnetic moment (i.e., spin state) of O2 through electron-mediated triplet energy transfer, resulting a spontaneous spin-flip process and highly specific 1O2 generation. These traits exemplify the opportunities that the surface engineering provides a unique strategy for excitonic regulation and will stimulate more research on exciton-triggering photocatalysis for solar energy conversion.

9.
Nano Lett ; 23(7): 2905-2914, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36961203

RESUMEN

Strain engineering is an attractive strategy for improving the intrinsic catalytic performance of heterogeneous catalysts. Manipulating strain on the short-range atomic scale to the local structure of the catalytic sites is still challenging. Herein, we successfully achieved atomic strain modulation on ultrathin layered vanadium oxide nanoribbons by an ingenious intercalation chemistry method. When trace sodium cations were introduced between the V2O5 layers (Na+-V2O5), the V-O bonds were stretched by the atomically strained vanadium sites, redistributing the local charges. The Na+-V2O5 demonstrated excellent photooxidation performance, which was approximately 12 and 14 times higher than that of pristine V2O5 and VO2, respectively. Complementary spectroscopy analysis and theoretical calculations confirmed that the atomically strained Na+-V2O5 had a high surficial charge density, improving the activation of oxygen molecules and contributing to the excellent photocatalytic property. This work provides a new approach for the rational design of strain-equipped catalysts for selective photooxidation reactions.

10.
Angew Chem Int Ed Engl ; 63(26): e202403996, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38679568

RESUMEN

Decreasing perovskite nanocrystal size increases radiative recombination due to the quantum confinement effect, but also increases the Auger recombination rate which leads to carrier imbalance in the emitting layers of electroluminescent devices. Here, we overcome this trade-off by increasing the exciton effective mass without affecting the size, which is realized through the trace Cd2+ doping of formamidinium lead bromide perovskite nanocrystals. We observe an ~2.7 times increase in the exciton binding energy benefiting from a slight distortion of the [BX6]4- octahedra caused by doping in the case of that the Auger recombination rate is almost unchanged. As a result, bright color-saturated green emitting perovskite nanocrystals with a photoluminescence quantum yield of 96 % are obtained. Cd2+ doping also shifts up the energy levels of the nanocrystals, relative to the Fermi level so that heavily n-doped emitters convert into only slightly n-doped ones; this boosts the charge injection efficiency of the corresponding light-emitting diodes. The light-emitting devices based on those nanocrystals reached a high external quantum efficiency of 29.4 % corresponding to a current efficiency of 123 cd A-1, and showed dramatically improved device lifetime, with a narrow bandwidth of 22 nm and Commission Internationale de I'Eclairage coordinates of (0.20, 0.76) for color-saturated green emission for the electroluminescence peak centered at 534 nm, thus being fully compliant with the latest standard for wide color gamut displays.

11.
BMC Plant Biol ; 23(1): 347, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37391710

RESUMEN

BACKGROUND: Conserved polycomb repressive complex 2 (PRC2) mediates H3K27me3 to direct transcriptional repression and has a key role in cell fate determination and cell differentiation in both animals and plants. PRC2 subunits have undergone independent multiplication and functional divergence in higher plants. However, relevant information is still absent in gymnosperms. RESULTS: To launch gymnosperm PRC2 research, we identified and cloned the PRC2 core component genes in the conifer model species Picea abies, including one Esc/FIE homolog PaFIE, two p55/MSI homologs PaMSI1a and PaMSI1b, two E(z) homologs PaKMT6A2 and PaKMT6A4, a Su(z)12 homolog PaEMF2 and a PaEMF2-like fragment. Phylogenetic and protein domain analyses were conducted. The Esc/FIE homologs were highly conserved in the land plant, except the monocots. The other gymnospermous PRC2 subunits underwent independent evolution with angiospermous species to different extents. The relative transcript levels of these genes were measured in endosperm and zygotic and somatic embryos at different developmental stages. The obtained results proposed the involvement of PaMSI1b and PaKMT6A4 in embryogenesis and PaKMT6A2 and PaEMF2 in the transition from embryos to seedlings. The PaEMF2-like fragment was predominantly expressed in the endosperm but not in the embryo. In addition, immunohistochemistry assay showed that H3K27me3 deposits were generally enriched at meristem regions during seed development in P. abies. CONCLUSIONS: This study reports the first characterization of the PRC2 core component genes in the coniferous species P. abies. Our work may enable a deeper understanding of the cell reprogramming process during seed and embryo development and may guide further research on embryonic potential and development in conifers.


Asunto(s)
Abies , Picea , Tracheophyta , Animales , Picea/genética , Histonas , Filogenia , Desarrollo Embrionario , Cycadopsida
12.
Cardiovasc Diabetol ; 22(1): 90, 2023 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-37076850

RESUMEN

BACKGROUND: The triglyceride-glucose (TyG) index, a simple measure of insulin resistance, is associated with intracranial atherosclerosis (ICAS) and stroke. In hypertensive populations, this association may be pronounced. The aim was to investigate the relationship between TyG and symptomatic intracranial atherosclerosis (sICAS) and recurrence risk in ischemic stroke patients with hypertension. METHODS: This prospective, multicenter cohort study included patients with acute minor ischemic stroke with a preadmission diagnosis of hypertension from September 2019 to November 2021 with a 3-month follow-up. The presence of sICAS was determined by a combination of clinical manifestations, the location of the infarction, and the corresponding artery with moderate-to-severe stenosis. ICAS burden was determined by the degree and number of ICAS occurrences. Fasting blood glucose (FBG) and triglyceride (TG) were measured to calculate TyG. The main outcome was ischemic stroke recurrence during the 90-day follow-up. Multivariate regression models were used to explore the association of TyG, sICAS, and ICAS burden with stroke recurrence. RESULTS: There were 1281 patients with a mean age of 61.6 ± 11.6 years; 70.1% were male, and 26.4% were diagnosed with sICAS. There were 117 patients who experienced stroke recurrence during follow-up. Patients were categorized according to quartiles of TyG. After adjusting for confounders, the risk of sICAS was greater (OR 1.59, 95% CI 1.04-2.43, p = 0.033) and the risk of stroke recurrence was significantly higher (HR 2.02, 95% CI 1.07-3.84, p = 0.025) in the fourth TyG quartile than in the first quartile. The restricted cubic spline (RCS) plot revealed a linear relationship between TyG and sICAS, and the threshold value for TyG was 8.4. Patients were then dichotomized into low and high TyG groups by the threshold. Patients with high TyG combined with sICAS had a higher risk of recurrence (HR 2.54, 95% CI 1.39-4.65) than patients with low TyG without sICAS. An interaction effect on stroke recurrence between TyG and sICAS was found (p = 0.043). CONCLUSION: TyG is a significant risk factor for sICAS in hypertensive patients, and there is a synergistic effect of sICAS and higher TyG on ischemic stroke recurrence. TRIAL REGISTRATION NUMBER: The study was registered on 16 August 2019 at https://www.chictr.org.cn/showprojen.aspx?proj=41160 (No. ChiCTR1900025214).


Asunto(s)
Hipertensión , Arteriosclerosis Intracraneal , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Estudios de Cohortes , Constricción Patológica , Estudios Prospectivos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Arterias , Hipertensión/diagnóstico , Hipertensión/epidemiología , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/epidemiología , Factores de Riesgo , Glucosa , Arteriosclerosis Intracraneal/diagnóstico por imagen , Arteriosclerosis Intracraneal/epidemiología , Triglicéridos , Glucemia , Biomarcadores
13.
Biometrics ; 79(3): 2404-2416, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36573805

RESUMEN

The network analysis plays an important role in numerous application domains including biomedicine. Estimation of the number of communities is a fundamental and critical issue in network analysis. Most existing studies assume that the number of communities is known a priori, or lack of rigorous theoretical guarantee on the estimation consistency. In this paper, we propose a regularized network embedding model to simultaneously estimate the community structure and the number of communities in a unified formulation. The proposed model equips network embedding with a novel composite regularization term, which pushes the embedding vector toward its center and pushes similar community centers collapsed with each other. A rigorous theoretical analysis is conducted, establishing asymptotic consistency in terms of community detection and estimation of the number of communities. Extensive numerical experiments have also been conducted on both synthetic networks and brain functional connectivity network, which demonstrate the superior performance of the proposed method compared with existing alternatives.


Asunto(s)
Algoritmos , Encéfalo
14.
Biometrics ; 79(4): 3564-3573, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37284764

RESUMEN

Community detection has attracted tremendous interests in network analysis, which aims at finding group of nodes with similar characteristics. Various detection methods have been developed to detect homogeneous communities in multi-layer networks, where inter-layer dependence is a widely acknowledged but severely under-investigated issue. In this paper, we propose a novel stochastic block Ising model (SBIM) to incorporate the inter-layer dependence to help with community detection in multi-layer networks. The community structure is modeled by the stochastic block model (SBM) and the inter-layer dependence is incorporated via the popular Ising model. Furthermore, we develop an efficient variational EM algorithm to tackle the resultant optimization task and establish the asymptotic consistency of the proposed method. Extensive simulated examples and a real example on gene co-expression multi-layer network data are also provided to demonstrate the advantage of the proposed method.


Asunto(s)
Algoritmos , Redes Reguladoras de Genes
15.
Physiol Plant ; 175(6): e14120, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38148206

RESUMEN

The small chemical N-1-naphthylphthalamic acid (NPA) has long been used as a polar auxin transport inhibitor. Recent biochemical and structural investigations have revealed that this molecule competes with the auxin IAA (indole-3-acetic acid) inside the PIN-FORMED auxin efflux carriers. However, the existence of any mutations in PIN family proteins capable of uncoupling the docking of IAA from NPA remains unclear. We report that Arabidopsis thaliana seedlings overexpressing SMALL AUXIN UP RNA 41 were hypersensitive to NPA-induced root elongation inhibition. We mutagenized this line to improve the genetic screening efficiency for NPA hyposensitivity mutants. Using bulked segregation analysis and mapping-by-sequencing assessment of these mutants, we identified a core genetic pathway for NPA-induced root elongation inhibition, including genes required for auxin biosynthesis, transportation, and signaling. To evaluate specific changes of auxin signaling activity in mutant roots before and after NPA treatment, the DR5::GFP/DR5::YFP markers were introduced and observed. Most importantly, we discovered a unique mutation in the PIN1 protein, substituting a proline residue with leucine at position 584, leading to a loss of NPA sensitivity while keeping the auxin efflux capacity. Transforming the null mutant pin1-201 with the PIN1::PIN1P584L -GFP fusion construct rescued the PIN1 function and provided NPA hyposensitivity. The proline residue is predicted to be adjacent to a hinge in the middle region of the ninth transmembrane helix of PIN1 and is conserved from moss to higher plants. Our work may bring new insights into the engineering of NPA-resistant PINs for auxin biology studies.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Ácidos Indolacéticos/metabolismo , Mutación/genética , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Prolina/metabolismo
16.
Artículo en Inglés | MEDLINE | ID: mdl-37310551

RESUMEN

BACKGROUND AND PURPOSE: The purpose of this study was to evaluate the association between different antiplatelet therapy regimens and the functional outcomes and bleeding complications among mild-to-moderate ischaemic stroke patients based on real-world data. METHODS: We used data from the SEACOAST trial (Safety and efficacy of aspirin-clopidogrel in acute noncardiogenic minor ischaemic stroke) to analyse the data of patients with mild-to-moderate stroke within 72 h after onset who were treated with aspirin or clopidogrel alone or a combination of clopidogrel and aspirin from September 2019 to November 2021. Propensity score matching (PSM) was used to balance the differences between groups. We performed an analysis to evaluate the association of different antiplatelet regimens and 90-day disability, which was defined as a modified Rankin Scale score ≥2, as well as disability ascribed to index or recurrent stroke by the local investigator. In terms of safety, we then compared the bleeding events between the two groups. RESULTS: A total of 2822 mild-to-moderate ischaemic stroke patients were treated with either clopidogrel plus aspirin (n = 1726, 61.2%) or aspirin/clopidogrel (n = 1096, 38.8%). Of 1726 patients in the dual antiplatelet group, 1350 (78.5%) received less than or equal to 30 days of combined therapy. At 90 days, 433 (15.3%) patients were disabled. Patients who received combined therapy had a lower overall disability rate (13.7% versus 17.9%; OR 0.78 (0.6-1.01); P = 0.064). However, investigators found that index stroke was the reason for significantly fewer patients in the dual antiplatelet group having disability (8.4% versus 12%; OR, 0.72 (0.52-0.98); P = 0.038). There was no statistically significant difference in the incidence of moderate to severe bleeding complications between the dual and mono antiplatelet drug regimens (0.4% versus 0.2%; HR 1.5 (0.25, 8.98); P = 0.657). CONCLUSION: Aspirin plus clopidogrel was associated with a reduction in the incidence of disability attributed to index stroke. There was no statistically significant difference in the incidence of moderate to severe bleeding complications between the two antiplatelet drug regimens. TRIAL REGISTRATION NUMBER: ChiCTR1900025214.

17.
Nano Lett ; 22(3): 1338-1344, 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35049298

RESUMEN

Quasi-2D perovskites, composed of self-organized quantum well structures, are emerging as gain materials for laser applications. Here we investigate the influence of domain distribution on the laser emission of CsPbCl1.5Br1.5-based quasi-2D perovskites. The use of 2,2-diphenylethylammonium bromide (DPEABr) as a ligand enables the formation of quasi-2D film with a large-n-dominated narrow domain distribution. Due to the reduced content of small-n domains, the incomplete energy transfer from small-n to large-n domains can be greatly addressed. Moreover, the photoinduced carriers can be concentrated on most of the large-n domains to reduce the local carrier density, thereby suppressing the Auger recombination. By controlling the domain distribution, we achieve blue amplified spontaneous emission and single-mode vertical-cavity surface-emitting lasing with low thresholds of 6.5 and 9.2 µJ cm-2, respectively. This work provides a guideline to design the domain distribution to realize low-threshold multicolor perovskite lasers.

18.
Int J Mol Sci ; 25(1)2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38203267

RESUMEN

As a plant-specific transcription factor, the SPL gene family plays a critical role in plant growth and development. Although the SPL gene family has been identified in diverse plant species, there have been no genome-wide identification or systematic study reports on the SPL gene family in Catalpa bungei. In this study, we identified 19 putative SPL gene family members in the C. bungei genome. According to the phylogenetic relationship, they can be divided into eight groups, and the genes in the same group have a similar gene structure and conserved motifs. Synteny analysis showed that fragment duplication played an important role in the expansion of the CbuSPL gene family. At the same time, CbuSPL genes have cis-acting elements and functions related to light response, hormone response, growth and development, and stress response. Tissue-specific expression and developmental period-specific expression analysis showed that CbuSPL may be involved in flowering initiation and development, flowering transition, and leaf development. In addition, the ectopic expression of CbuSPL4 in Arabidopsis confirmed that it can promote early flowering and induce the expression of related flowering genes. These systematic research results will lay a foundation for further study on the functional analysis of SPL genes in C. bungei.


Asunto(s)
Arabidopsis , Lepidópteros , Animales , Factores de Transcripción/genética , Filogenia , Regulación de la Expresión Génica , Regiones Promotoras Genéticas , Arabidopsis/genética
19.
Molecules ; 28(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36677586

RESUMEN

The polysaccharides isolated and purified from different parts of the medicinal fungus Cordyceps cicadae were identified, and three extracts displaying significant biological activities were selected for further study. The bacterium substance polysaccharides (BSP), spore powder polysaccharides (SPP), and pure powder polysaccharides (PPP) were separated, purified, and collected from the sclerotia, spores, and fruiting bodies of Cordyceps cicadae, respectively. The structures of Cordyceps cicadae polysaccharides were analyzed using gas chromatography, Fourier-transform infrared spectroscopy, methylation analysis, and one-dimensional (1H and 13C) nuclear magnetic resonance spectroscopy. Moreover, the hypoglycemic effect of Cordyceps cicadae polysaccharides was examined in both in vitro and in vivo models. BSP, SPP, and PPP significantly increased glucose absorption in HepG2 cells, and alleviated insulin resistance (IR) in the in vitro model. SPP was the most effective, and was therefore selected for further study of its hypoglycemic effect in vivo. SPP effectively improved body weight and glucose and lipid metabolism in type 2 diabetes model mice, in addition to exerting a protective effect on liver injury. SPP regulated the mRNA expression of key PI3K/Akt genes involved in the insulin signaling pathway. The hypoglycemic mechanism of SPP may reduce hepatic insulin resistance by activating the PI3K/Akt signaling pathway. Spore powder polysaccharides (SPP) extracted from Cordyceps cicadae effectively improved body weight and glucose and lipid metabolism in type 2 diabetes model mice, in addition to exerting a protective effect on liver injury. The mechanism underlying the hypoglycemic effect of SPP regulates the mRNA expression of key PI3K/Akt genes involved in the insulin signaling pathway to alleviate insulin resistance. Our results provide a theoretical basis for research into the hypoglycemic effect of Cordyceps cicadae, and lay the foundation for the development of functional products.


Asunto(s)
Cordyceps , Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Ratones , Animales , Hipoglucemiantes/farmacología , Fosfatidilinositol 3-Quinasas , Polvos , Proteínas Proto-Oncogénicas c-akt , Polisacáridos/química , Cordyceps/química , Insulina , Glucosa , ARN Mensajero
20.
BMC Oral Health ; 23(1): 283, 2023 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-37173683

RESUMEN

BACKGROUND: A laser doppler flowmetry (LDF) test can reflect the pulp vitality caused by the change in pulp blood flow (PBF). This study aimed to investigate the PBF of the permanent maxillary incisors using LDF and to calculate the clinical reference range and coincidence rate for pulp vitality using PBF as an indicator. METHODS: School-age children (7-12 years) were recruited randomly. A total of 455 children (216 female and 239 male) were included in this study. An additional 395 children (7-12 years) who attended the department due to anterior tooth trauma from October 2015 to February 2018 were included to assess the clinical occurrence rate. The PBF was measured using LDF equipment and an LDF probe. RESULTS: The clinical reference range of PBF values for the permanent maxillary incisors (teeth 11, 12, 21, and 22) in children were from 7 to 14 perfusion units (PU), 11 (6.016; 11.900 PU), 12 (6.677; 14.129 PU), 21 (6.043;11.899 PU), and 22 (6.668; 14.174 PU). There was a statistically significant correlation between PBF and children's age (p < 0.000) without any significant gender discrimination (p = 0.395). For all incisors, for any age group, the PBF detection value of the lateral incisors was significantly higher than that of the central incisors (p < 0.05). The clinical coincidence rate of detecting PBF in the traumatic teeth was 90.42% and the sensitivity and specificity were 36.99% and 99.88%, respectively. CONCLUSIONS: The determination of the PBF clinical reference range and clinical coincidence rate for the permanent maxillary incisors in children using LDF provided a promising theoretical basis for clinical applications.


Asunto(s)
Pueblos del Este de Asia , Incisivo , Humanos , Masculino , Niño , Femenino , Incisivo/lesiones , Flujometría por Láser-Doppler , Valores de Referencia , Pulpa Dental/irrigación sanguínea
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