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1.
Nature ; 601(7894): 568-572, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35082423

RESUMEN

The Leidenfrost effect, namely the levitation of drops on hot solids1, is known to deteriorate heat transfer at high temperature2. The Leidenfrost point can be elevated by texturing materials to favour the solid-liquid contact2-10 and by arranging channels at the surface to decouple the wetting phenomena from the vapour dynamics3. However, maximizing both the Leidenfrost point and thermal cooling across a wide range of temperatures can be mutually exclusive3,7,8. Here we report a rational design of structured thermal armours that inhibit the Leidenfrost effect up to 1,150 °C, that is, 600 °C more than previously attained, yet preserving heat transfer. Our design consists of steel pillars serving as thermal bridges, an embedded insulating membrane that wicks and spreads the liquid and U-shaped channels for vapour evacuation. The coexistence of materials with contrasting thermal and geometrical properties cooperatively transforms normally uniform temperatures into non-uniform ones, generates lateral wicking at all temperatures and enhances thermal cooling. Structured thermal armours are limited only by their melting point, rather than by a failure in the design. The material can be made flexible, and thus attached to substrates otherwise challenging to structure. Our strategy holds the potential to enable the implementation of efficient water cooling at ultra-high solid temperatures, which is, to date, an uncharted property.

2.
Genome Res ; 33(3): 463-477, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-37310928

RESUMEN

Structural variations (SVs) are a major contributor to genetic diversity and phenotypic variations, but their prevalence and functions in domestic animals are largely unexplored. Here we generated high-quality genome assemblies for 15 individuals from genetically diverse sheep breeds using Pacific Biosciences (PacBio) high-fidelity sequencing, discovering 130.3 Mb nonreference sequences, from which 588 genes were annotated. A total of 149,158 biallelic insertions/deletions, 6531 divergent alleles, and 14,707 multiallelic variations with precise breakpoints were discovered. The SV spectrum is characterized by an excess of derived insertions compared to deletions (94,422 vs. 33,571), suggesting recent active LINE expansions in sheep. Nearly half of the SVs display low to moderate linkage disequilibrium with surrounding single-nucleotide polymorphisms (SNPs) and most SVs cannot be tagged by SNP probes from the widely used ovine 50K SNP chip. We identified 865 population-stratified SVs including 122 SVs possibly derived in the domestication process among 690 individuals from sheep breeds worldwide. A novel 168-bp insertion in the 5' untranslated region (5' UTR) of HOXB13 is found at high frequency in long-tailed sheep. Further genome-wide association study and gene expression analyses suggest that this mutation is causative for the long-tail trait. In summary, we have developed a panel of high-quality de novo assemblies and present a catalog of structural variations in sheep. Our data capture abundant candidate functional variations that were previously unexplored and provide a fundamental resource for understanding trait biology in sheep.


Asunto(s)
Estudio de Asociación del Genoma Completo , Cola (estructura animal) , Animales , Ovinos/genética , Regiones no Traducidas 5' , Alelos , Fenotipo
3.
Mol Cell Proteomics ; 22(8): 100602, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37343696

RESUMEN

Treatment and relevant targets for breast cancer (BC) remain limited, especially for triple-negative BC (TNBC). We identified 6091 proteins of 76 human BC cell lines using data-independent acquisition (DIA). Integrating our proteomic findings with prior multi-omics datasets, we found that including proteomics data improved drug sensitivity predictions and provided insights into the mechanisms of action. We subsequently profiled the proteomic changes in nine cell lines (five TNBC and four non-TNBC) treated with EGFR/AKT/mTOR inhibitors. In TNBC, metabolism pathways were dysregulated after EGFR/mTOR inhibitor treatment, while RNA modification and cell cycle pathways were affected by AKT inhibitor. This systematic multi-omics and in-depth analysis of the proteome of BC cells can help prioritize potential therapeutic targets and provide insights into adaptive resistance in TNBC.


Asunto(s)
Transducción de Señal , Neoplasias de la Mama Triple Negativas , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteómica , Proliferación Celular , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Neoplasias de la Mama Triple Negativas/metabolismo , Receptores ErbB/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(2)2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-34992136

RESUMEN

Various physical tweezers for manipulating liquid droplets based on optical, electrical, magnetic, acoustic, or other external fields have emerged and revolutionized research and application in medical, biological, and environmental fields. Despite notable progress, the existing modalities for droplet control and manipulation are still limited by the extra responsive additives and relatively poor controllability in terms of droplet motion behaviors, such as distance, velocity, and direction. Herein, we report a versatile droplet electrostatic tweezer (DEST) for remotely and programmatically trapping or guiding the liquid droplets under diverse conditions, such as in open and closed spaces and on flat and tilted surfaces as well as in oil medium. DEST, leveraging on the coulomb attraction force resulting from its electrostatic induction to a droplet, could manipulate droplets of various compositions, volumes, and arrays on various substrates, offering a potential platform for a series of applications, such as high-throughput surface-enhanced Raman spectroscopy detection with single measuring time less than 20 s.


Asunto(s)
Pinzas Ópticas , Electricidad Estática , Acústica , Magnetismo , Espectrometría Raman
5.
BMC Biol ; 22(1): 64, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38481288

RESUMEN

BACKGROUND: Studies on maize evolution and domestication are largely limited to the nuclear genomes, and the contribution of cytoplasmic genomes to selection and domestication of modern maize remains elusive. Maize cytoplasmic genomes have been classified into fertile (NA and NB) and cytoplasmic-nuclear male-sterility (CMS-S, CMS-C, and CMS-T) groups, but their contributions to modern maize breeding have not been systematically investigated. RESULTS: Here we report co-selection and convergent evolution between nuclear and cytoplasmic genomes by analyzing whole genome sequencing data of 630 maize accessions modern maize and its relatives, including 24 fully assembled mitochondrial and chloroplast genomes. We show that the NB cytotype is associated with the expansion of modern maize to North America, gradually replaces the fertile NA cytotype probably through unequal division, and predominates in over 90% of modern elite inbred lines. The mode of cytoplasmic evolution is increased nucleotypic diversity among the genes involved in photosynthesis and energy metabolism, which are driven by selection and domestication. Furthermore, genome-wide association study reveals correlation of cytoplasmic nucleotypic variation with key agronomic and reproductive traits accompanied with the diversification of the nuclear genomes. CONCLUSIONS: Our results indicate convergent evolution between cytoplasmic and nuclear genomes during maize domestication and breeding. These new insights into the important roles of mitochondrial and chloroplast genomes in maize domestication and improvement should help select elite inbred lines to improve yield stability and crop resilience of maize hybrids.


Asunto(s)
Domesticación , Zea mays , Zea mays/genética , Estudio de Asociación del Genoma Completo , Fitomejoramiento , Citoplasma
6.
Bioconjug Chem ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38989881

RESUMEN

In this study, maleic anhydride-modified lignin (LG-M), a ROS-cleavable thioketal (TK) bond, and polyethylene glycol (PEG) were used to synthesize a lignin-based copolymer (LG-M(TK)-PEG). Doxorubicin (DOX) was attached to the ROS-cleavable bond in the LG-M(TK)-PEG for the preparation of the ROS-activatable DOX prodrug (LG-M(TK-DOX)-PEG). Nanoparticles (NPs) with a size of 125.7 ± 3.1 nm were prepared by using LG-M(TK-DOX)-PEG, and they exhibited enhanced uptake by cancer cells compared to free DOX. Notably, the presence of lignin in the nanoparticles could boost ROS production in breast cancer 4T1 cells while showing little effect on L929 normal cells. This selective effect facilitated the specific activation of the DOX prodrug in the tumor microenvironment, resulting in the superior tumor inhibitory effects and enhanced biosafety relative to free DOX. This work demonstrates the potential of the LG-M(TK-DOX)-PEG NPs as an efficient drug delivery system for cancer treatment.

7.
BMC Infect Dis ; 24(1): 514, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778273

RESUMEN

BACKGROUND: As is known, CD4 cell count is a significant parameter predicting HIV progression, opportunistic infections and death in HIV-infected individuals, as well was an important indicator for initiating antiretroviral therapy (ART). In China's National Free Antiretroviral Treatment Program, people with HIV (PWH) on ART can receive a CD4 count test at least once every six months. Importantly, the baseline CD4 count (before ART initiation) is significantly correlated with ART and even prognosis, but the influence of the peak CD4 cell count on ART and/or clinical outcomes is still unknown. METHODS: A retrospective study was conducted among 7965 PWH who received ART from October 2003 to September 2022 at Yunnan Infectious Disease Hospital. Clinical features and laboratory data were collected and analyzed by Chi-square test, univariate and multivariate Cox regression analysis. After elimination of confounding variables, multivariate Cox regression analysis was performed to identify survival-related factors. RESULTS: Of a total of 7965 PWH in the ART treatment cohort who met the inclusion and exclusion criteria, 7939 were finally included in the subsequent analyses. First, it was found that the proportion of clinical variables, including sex, age distribution, interval from diagnosis to ART initiation, marital status, and others, was significantly different between the living and dead groups (P < 0.05). Impressively, significantly more PWH had the higher level of baseline, peak and recent CD4 cell counts in the living group compared to those in the dead group. Due to multicollinearity effect, after excluding confounders, the following factors were found to be significantly associated with mortality by multivariate Cox regression analysis: (1) male sex (hazard ratio (HR) = 1.268 [1.032, 1.559]; P = 0.024); (2) time from HIV confirmation to ART initiation ≥ 6 months (HR = 1.962 [1.631, 2.360]; P < 0.001); (3) peak CD4 cell count: Peak CD4 < 100cells/µL group (HR = 16.093 [12.041, 21.508]; P < 0.001), 100cells/µL ≤ x < 200cells/µL group (HR = 7.904 [6.148, 10.160]; P < 0.001), 200cells/µL ≤ x < 350cells/µL group (HR = 3.166 [2.519, 3.980]; P < 0.001), 350cells/µL ≤ x < 500cells/µL group (HR = 1.668 [1.291, 2.155]; P < 0.001). CONCLUSION: Interestingly, patients in male, time from HIV confirmation to ART initiation ≥ 6 months, or peak CD4 count < 500 cells/µl had inferior clinical outcomes, in other word, a lower peak CD4 cell count significantly increased the risk of death, and peak CD4 cell was independent in predicting the overall survival of PWH. It is important to promote "early diagnosis and treatment of HIV" and regularly monitor CD4 levels in HIV/AIDS to evaluate the efficacy of ART and immune reconstitution, and optimize the ART regimen in time to further reduce the mortality of PWH.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Humanos , Estudios Retrospectivos , Masculino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/mortalidad , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Femenino , Adulto , Recuento de Linfocito CD4 , Persona de Mediana Edad , China/epidemiología , Fármacos Anti-VIH/uso terapéutico , Resultado del Tratamiento , Adulto Joven , Terapia Antirretroviral Altamente Activa
8.
Artículo en Inglés | MEDLINE | ID: mdl-38595136

RESUMEN

OBJECTIVE: Conventional imaging protocols, including sagittal T1-weighted imaging (T1WI) and water-only T2-weighted imaging (T2WI), are time consuming when screening for spinal metastases with vertebral compression fractures (VCFs). In this study, we aimed to assess the accuracy of using only the Dixon T2-weighted sequence in the diagnosis of spinal metastases with VCFs to determine its suitability as a simplified protocol for this task. METHODS: This retrospective study included 27 patients diagnosed with spinal metastases and VCFs. Qualitative analysis was performed separately by two musculoskeletal radiologists, who independently performed diagnostic evaluations of each vertebra using both conventional and simplified protocols. McNemar's test was then used to compare the differences in diagnostic results, and Cohen's kappa coefficient was used to assess interobserver and interprotocol agreement. Diagnostic performance values for both protocols, including sensitivity, specificity, and area under the curve, were then determined based on the reference standard. Quantitative image analysis was performed randomly for 30 metastases on T1WI and fat-only T2WI to measure the signal intensity, signal-to-noise ratio, and contrast-to-noise ratio. RESULTS: The diagnosis of VCFs by both radiologists was in full agreement with the reference standard. The classification of spinal metastases and diagnostic performance values determined by both radiologists were not significantly different between the two protocols (all P > 0.05), and the consistency between observers and protocols was excellent (κ = 0.973-0.991). The contrast-to-noise ratio of fat-only T2WI was significantly higher than that of T1WI (P < 0.001). CONCLUSIONS: The Dixon T2-weighted sequence alone performed well in diagnosing spinal metastases with VCFs, performing no worse than the conventional protocol (T1WI and water-only T2WI). This suggests that the Dixon T2-weighted sequence alone can serve as a simplified protocol for the diagnosis of spinal metastases with VCFs, thereby avoiding the need for more intricate scanning procedures.

9.
BMC Geriatr ; 24(1): 535, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902614

RESUMEN

BACKGROUND: Postoperative delirium (POD) is a common complication among elderly patients after surgery. The Naples Prognostic Score (NPS), a novel prognostic marker based on immune-inflammatory and nutritional status, was widely used in the assessment of the prognosis of surgical patients. However, no study has evaluated the relationship between NPS and POD. The aim of this article was to investigate the association between NPS and POD and test the predictive efficacy of preoperative NPS for POD in elderly patients with gastrointestinal tumors. MATERIALS AND METHODS: In the present study, we retrospectively collected perioperative data of 176 patients (≥ 60 years) who underwent elective gastrointestinal tumor surgery from June 2022 to September 2023. POD was defined according to the chart-based method and the NPS was calculated for each patient. We compared all the demographics and laboratory data between POD and non-POD groups. Univariate and multivariate logistic regression analysis was used to explore risk factors of POD. Moreover, the accuracy of NPS in predicting POD was further assessed by utilizing receiver operating characteristic (ROC) curves. RESULTS: 20 had POD (11.4%) in a total of 176 patients, with a median age of 71 (65-76). The outcomes by univariate analysis pointed out that age, ASA status ≥ 3, creatinine, white blood cell count, fasting blood glucose (FBG), and NPS were associated with the risk of POD. Multivariate logistic regression analysis further showed that age, ASA grade ≥ 3, FBG and NPS were independent risk factors of POD. Additionally, the ROC curves revealed that NPS allowed better prognostic capacity for POD than other variables with the largest area under the curve (AUC) of 0.798, sensitivity of 0.800 and specificity of 0.667, respectively. CONCLUSION: Age, ASA grade ≥ 3, and FBG were independent risk factors for POD in the elderly underwent gastrointestinal tumor surgery. Notably, the preoperative NPS was a more effective tool in predicting the incidence of POD, but prospective trials were still needed to further validate our conclusion. TRIAL REGISTRATION: The registration information for the experiment was shown below. (date: 3rd January 2024; number: ChiCTR2400079459).


Asunto(s)
Neoplasias Gastrointestinales , Complicaciones Posoperatorias , Humanos , Masculino , Femenino , Anciano , Neoplasias Gastrointestinales/cirugía , Neoplasias Gastrointestinales/complicaciones , Estudios Retrospectivos , Pronóstico , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Delirio/diagnóstico , Delirio/etiología , Delirio/epidemiología , Valor Predictivo de las Pruebas , Factores de Riesgo , Persona de Mediana Edad , Curva ROC
10.
BMC Anesthesiol ; 24(1): 104, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38504188

RESUMEN

BACKGROUND: The purpose of the present study was to systematically delve into the efficacy and safety of transcutaneous electrical acupoint stimulation (TEAS) on the quality of recovery after general anesthesia. METHODS: Randomized controlled trials related to TEAS improving postoperative recovery quality were searched in Cochrane Library, Web of Science, Embase, PubMed, CNKI, VIP, Wanfang and Chinese biomedical database from the inception of each database to June 2023. After literature screening and data extraction, Stata15 software was employed for meta-analysis, and the quality of the included literature was evaluated utilizing ROB2. RESULTS: The study included 10 articles involving 2,383 patients in total. The meta-analysis results unveiled that TEAS could improve 24-hour and 48-hour postoperative QoR-40 scores as well as 24-hour postoperative QoR-40 dimension scores [WMD = 8.52, 95%CI (5.12, 11.91), P < 0.001; WMD = 1.99, 95%CI (0.91, 3.07), P < 0.001], emotional state [WMD = 1.38, 95%CI (0.66, 2.09), P < 0.001], physical comfort [WMD = 2.99, 95%CI (1.59, 4.39), P < 0.001], psychological support [WMD = 0.63, 95%CI (0.36, 0.90), P < 0.001], and physical independence [WMD = 0.76, 95%CI (0.22, 1.30), P = 0.006]; pain [WMD = 1.81, 95%CI (0.87, 2.75), P < 0.001]; decrease 24-hour postoperative VAS pain scores [WMD = -0.84, 95%CI (-1.45, -0.23), P = 0.007] and the incidence of postoperative nausea and vomiting [RR = 0.88, 95%CI (0.81, 0.97), P = 0.006; RR = 0.62, 95%CI (0.52, 0.73), P < 0.001]. CONCLUSION: TEAS can improve postoperative QoR-40 scores and the quality of recovery, relieve pain, and decrease the incidence of nausea and vomiting after surgery in patients who underwent general anesthesia. TRIAL REGISTRATION: CRD42023433959.


Asunto(s)
Puntos de Acupuntura , Estimulación Eléctrica Transcutánea del Nervio , Humanos , Estimulación Eléctrica Transcutánea del Nervio/métodos , Náusea y Vómito Posoperatorios/epidemiología , Náusea y Vómito Posoperatorios/prevención & control , Dolor Postoperatorio/prevención & control , Dolor Postoperatorio/epidemiología , Periodo Posoperatorio
11.
Int J Mol Sci ; 25(11)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38892181

RESUMEN

Potato (Solanum tuberosum L.) is a major global food crop, and oxidative stress can significantly impact its growth. Previous studies have shown that its resistance to oxidative stress is mainly related to transcription factors, post-translational modifications, and antioxidant enzymes in vivo, but the specific molecular mechanisms remain unclear. In this study, we analyzed the transcriptome data from potato leaves treated with H2O2 and Methyl viologen (MV), and a control group, for 12 h. We enriched 8334 (CK vs. H2O2) and 4445 (CK vs. MV) differentially expressed genes (DEGs), respectively, and randomly selected 15 DEGs to verify the sequencing data by qRT-PCR. Gene ontology (GO) enrichment analysis showed that the DEGs were mainly concentrated in cellular components and related to molecular function, and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that most of the DEGs were related to metabolic pathways, plant hormone signal transduction, MAPK-signaling pathway, and plant-pathogen interactions. In addition, several candidate transcription factors, mainly including MYB, WRKY, and genes associated with Ca2+-mediated signal transduction, were also found to be differentially expressed. Among them, the plant hormone genes Soltu.DM.03G022780 and Soltu.DM.06G019360, the CNGC gene Soltu.DM.06G006320, the MYB transcription factors Soltu.DM.06G004450 and Soltu.DM.09G002130, and the WRKY transcription factor Soltu.DM.06G020440 were noticeably highly expressed, which indicates that these are likely to be the key genes in the regulation of oxidative stress tolerance. Overall, these findings lay the foundation for further studies on the molecular mechanisms of potato leaves in response to oxidative stress.


Asunto(s)
Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Estrés Oxidativo , Hojas de la Planta , Solanum tuberosum , Transcriptoma , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Perfilación de la Expresión Génica/métodos , Ontología de Genes , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/farmacología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
12.
Int J Environ Health Res ; 34(5): 2333-2352, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37610216

RESUMEN

A systematic review and meta-analysis was conducted to evaluate recent epidemiological evidence on the association of air pollution with congenital anomalies (CAs). Of 11,014 records, 49 were finally included in this meta-analysis. Per 10 µg/m3 increase in air pollutant, PM10 exposure during the 1st month of pregnancy and at the first trimester (T1) was associated with increased overall CAs. Further, exposure to PM10 was associated with congenital heart disease (OR = 1.055, 95% CI: 1.035, 1.074) and patent ductus arteriosus (OR = 1.094, 95% CI: 1.020, 1.168) at T1, with chromosomal anomalies during the entire pregnancy and with nervous system anomalies when exposure occurred 3 months prior to pregnancy, during the 1st, 2nd months of pregnancy and at T1. Besides, a significant association with overall CAs was observed for a combined exposure of PM10 and SO2 during the 1st month of gestation (OR: 1.101, 95% CI: 1.023, 1.180). A combined exposure of PM10 and CO was also associated with tetralogy of Fallot during 3-8 weeks of gestation (OR: 1.016, 95% CI: 1.005, 1.027). No significant associations were observed between PM2.5, NO2, and O3 exposure and CAs.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Ozono , Embarazo , Femenino , Humanos , Ozono/análisis , Material Particulado/toxicidad , Material Particulado/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Estudios Epidemiológicos , Exposición a Riesgos Ambientales/análisis , Dióxido de Nitrógeno/análisis
13.
Int J Environ Health Res ; 34(2): 1053-1063, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36987736

RESUMEN

Retinol-binding protein 4 (RBP4) was controversially associated with type 2 diabetes mellitus (T2DM). This meta-analysis aimed at evaluating the association between RBP4 level and T2DM risk. MEDLINE and EMBASE were searched to identify relevant studies up to 3 December 2022. Random effects model was used to pool multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Publication bias was estimated by Funnel plot and Egger's test, it was considered to be significant when P < 0.05. Eight studies including 8087 participants were finally included. Compared to those with the lowest level, subjects with the highest level of RBP4 have a higher risk of T2DM (OR = 1.47, 95% CI: 1.16-1.78, P < 0.001, I2 = 86.9%). No publication bias among the included studies was found (t = 0.94, P = 0.377). This meta-analysis indicated that high RBP4 level was associated with increasing risk of T2DM.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/metabolismo , Proteínas Plasmáticas de Unión al Retinol
14.
J Perianesth Nurs ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38904602

RESUMEN

PURPOSE: Stress response is a common complication during extubation, mainly manifested by dramatic hemodynamic fluctuations. Transcutaneous electrical acupoint stimulation (TEAS) is widely applied in the perioperative period. We performed this meta-analysis to evaluate whether the TEAS could relieve the stress response during extubation in noncardiac surgery patients. DESIGN: A systematic review and meta-analysis of randomized controlled trials. METHODS: We searched six databases (PubMed, Web of Science, Embase, Cochrane Library, China National Knowledge Infrastructure, CNKI, and Wan Fang) for relevant literature. A risk of bias assessment was executed based on the Cochrane Criteria. We applied RevMan5.4.1 software to analyze data. When the χ2 test did not show heterogeneity, we adopted the fixed-effect model. Otherwise, the random-effect model was used. FINDINGS: ln total, 12 randomized controlled trials with 1,347 participants were enrolled in this meta-analysis. Meta-analysis showed the heart rate and mean arterial pressure of the intervention group were significantly lower than the control group at immediately, 5 minutes, and 10 minutes after extubation. The occurrence rate of emergency agitation (RR 0.39, 95% CI [0.26,0.60]) and postoperative delirium (RR 0.40, 95% CI [0.22, 0.72] were also lower in the TEAS group. The consumption of propofol (standardized mean difference (SMD) 0.47, 95% CI [-0.77, -0.18]) and remifentanil (SMD 1.49, 95% CI [-2.01, -0.96]) of the intervention group were also significantly reduced compared with the control group. CONCLUSIONS: TEAS was beneficial for improving stress response during extubation, emergence agitation, postoperative delirium, and reduced the consumption of intraoperative propofol and remifentanil, but it was necessary to note the limitations of the current evidence.

15.
Angew Chem Int Ed Engl ; 63(1): e202315340, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-37985934

RESUMEN

Despite the fact that d-band center theory links the d electron structure of transition metals to their catalytic activity, it is yet unknown how the synergistic effect of multi-d electrons impacts catalytic performance. Herein, novel LaNi1-x Cox Ru intermetallics containing 5d, 4d, and 3d electrons were prepared. In these compounds, the 5d orbital of La transfers electrons to the 4d orbital of Ru, which provides adsorption sites for H*. The 3d orbitals of Ni and Co interact with the 5d and 4d orbitals to generate an anisotropic electron distribution, which facilitates the adsorption and desorption of OH*. The synergistic effect of multi-d electrons ensures efficient catalytic activity. The optimized LaNi0.5 Co0.5 Ru has an overpotential of 43mV at 10 mA cm-2 for alkaline electrocatalytic hydrogen evolution reaction. Beyond offering a variety of new electrocatalysts, this work reveals the multi-d electron synergy in promoting catalytic reaction.

16.
Angew Chem Int Ed Engl ; 63(4): e202316550, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38038407

RESUMEN

Single-atom alloys (SAAs), combining the advantages of single-atom and nanoparticles (NPs), play an extremely significant role in the field of heterogeneous catalysis. Nevertheless, understanding the catalytic mechanism of SAAs in catalysis reactions remains a challenge compared with single atoms and NPs. Herein, ruthenium-nickel SAAs (RuNiSAAs ) synthesized by embedding atomically dispersed Ru in Ni NPs are anchored on two-dimensional Ti3 C2 Tx MXene. The RuNiSAA-3 -Ti3 C2 Tx catalysts exhibit unprecedented activity for hydrogen evolution from ammonia borane (AB, NH3 BH3 ) hydrolysis with a mass-specific activity (rmass ) value of 333 L min-1 gRu -1 . Theoretical calculations reveal that the anchoring of SAAs on Ti3 C2 Tx optimizes the dissociation of AB and H2 O as well as the binding ability of H* intermediates during AB hydrolysis due to the d-band structural modulation caused by the alloying effect and metal-supports interactions (MSI) compared with single atoms and NPs. This work provides useful design principles for developing and optimizing efficient hydrogen-related catalysts and demonstrates the advantages of SAAs over NPs and single atoms in energy catalysis.

17.
Angew Chem Int Ed Engl ; : e202408193, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802317

RESUMEN

Hydrolysis of ammonia borane (NH3BH3, AB) involves multiple undefined steps and complex adsorption and activation, so single or dual sites are not enough to rapidly achieve the multi-step catalytic processes. Designing multi-site catalysts is necessary to enhance the catalytic performance of AB hydrolysis reactions but revealing the matching reaction mechanisms of AB hydrolysis is a great challenge. In this work, we propose to construct RuPt-Ti multi-site catalysts to clarify the multi-site tandem activation mechanism of AB hydrolysis. Experimental and theoretical studies reveal that the multi-site tandem mode can respectively promote the activation of NH3BH3 and H2O molecules on the Ru and Pt sites as well as facilitate the fast transfer of *H and the desorption of H2 on Ti sites at the same time. RuPt-Ti multi-site catalysts exhibit the highest turnover frequency (TOF) of 1293 min-1 for AB hydrolysis reaction, outperforming the single-site Ru, dual-site RuPt and Ru-Ti catalysts. This study proposes a multi-site tandem concept for accelerating the dehydrogenation of hydrogen storage material, aiming to contribute to the development of cleaner, low-carbon, and high-performance hydrogen production systems.

18.
Small ; 19(43): e2303031, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37356067

RESUMEN

Bimetallic Nanoalloy catalysts have diverse uses in clean energy, sensing, catalysis, biomedicine, and energy storage, with some supported and unsupported catalysts. Conventional synthetic methods for producing bimetallic alloy nanoparticles often produce unalloyed and bulky particles that do not exhibit desired characteristics. Alloys, when prepared with advanced nanoscale methods, give higher surface area, activity, and selectivity than individual metals due to changes in their electronic properties and reduced size. This review demonstrates the synthesis methods and principles to produce and characterize highly dispersed, well-alloyed bimetallic nanoalloy particles in relatively simple, effective, and generalized approaches and the overall existence of conventional synthetic methods with modifications to prepare bimetallic alloy catalysts. The basic concepts and mechanistic understanding are represented with purposely selected examples. Herein, the enthralling properties with widespread applications of nanoalloy catalysts in heterogeneous catalysis are also presented, especially for Hydrogen Evolution Reaction (HER), Oxidation Reduction Reaction (ORR), Oxygen Evolution Reaction (OER), and alcohol oxidation with a particular focus on Pt and Pd-based bimetallic nanoalloys and their numerous fields of applications. The high entropy alloy is described as a complicated subject with an emphasis on laser-based green synthesis of nanoparticles and, in conclusion, the forecasts and contemporary challenges for the controlled synthesis of nanoalloys are addressed.

19.
Small ; : e2304635, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37786271

RESUMEN

Rapid detachment of impacting droplets from underlying substrate is highly preferred for mass, momentum, and energy exchange in many practical applications. Driven by this, the past several years have witnessed a surge in engineering macrotexture to reduce solid-liquid contact time. Despite these advances, these strategies in reducing contact time necessitate the elegant control of either the spatial location for droplet contact or the range of impacting velocity. Here, this work circumvents these limitations by designing a dual gradient surface consisting of a vertical spacing gradient made of tapered pillar arrays and a lateral curvature gradient characterized as macroscopic convex. This design enables the impacting droplets to self-adapt to asymmetric or pancake bouncing mode accordingly, which renders significant contact time reduction (up to ≈70%) for a broad range of impacting velocities (≈0.4-1.4 m s-1 ) irrespective of the spatial impacting location. This new design provides a new insight for designing liquid-repellent surfaces, and offers opportunities for applications including dropwise condensation, energy conversion, and anti-icing.

20.
Artículo en Inglés | MEDLINE | ID: mdl-36951905

RESUMEN

A novel moderately thermophilic heterotrophic bacterium, designated strain 143-21T, was isolated from a deep-sea hydrothermal chimney sample collected from the Central Indian Ridge at a depth of 2 440 m. Phylogenetic analysis indicated that strain 143-21T belongs to the genus Crassaminicella. It was most closely related to Crassaminicella thermophila SY095T (96.79 % 16S rRNA gene sequence similarity) and Crassaminicella profunda Ra1766HT (96.52 %). Genomic analysis showed that strain 143-21T shares 79.79-84.45 % average nucleotide identity and 23.50-29.20 % digital DNA-DNA hybridization with the species of the genus Crassaminicella, respectively. Cells were rod-shaped, non-motile, Gram-positive-staining. Terminal endospores were observed in stationary-phase cells when strain 143-21T was grown on Thermococcales rich medium. Strain 143-21T was able to grow at 30-60 °C (optimum, 50 °C), pH 6.5-8.5 (optimum, pH 7.0) and in 1.0-7.0 % NaCl (w/v; optimum 2.0 %, w/v). Strain 143-21T utilized fructose, glucose, maltose, mannose, ribose, N-acetyl-d-(+)-glucosamine and casamino acids, as well as amino acids including glutamate, lysine, histidine and cysteine. The main fermentation products from glucose were acetate (2.07 mM), H2 and CO2. It did not reduce elemental sulphur, sulphate, thiosulphate, sulphite, fumarate, nitrate, nitrite and Fe (III). The predominant cellular fatty acids were C14 : 0 (48.8 %), C16 : 0 (12.9 %), and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c; 10.2 %). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol, as well as two unidentified phospholipids and four unidentified aminolipids. No respiratory quinones were detected. Based on its phylogenetic analysis and physiological characteristics, strain 143-21T is considered to represent a novel species of the genus Crassaminicella, for which the name Crassaminicella indica sp. nov. is proposed. The type strain is strain 143-21T (=DSM 114408T= MCCC 1K06400T).


Asunto(s)
Ácidos Grasos , Respiraderos Hidrotermales , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Composición de Base , Respiraderos Hidrotermales/microbiología , Anaerobiosis , Análisis de Secuencia de ADN , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Fosfolípidos/química , Bacterias Anaerobias
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