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1.
Curr Biol ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39260360

RESUMEN

Diet is one of the most important aspects of an animal's ecology, as it reflects direct interactions with other organisms and shapes morphology, behavior, and other life history traits. Modern birds (Neornithes) have a highly efficient and phenotypically plastic digestive system, allowing them to utilize diverse trophic resources, and digestive function has been put forth as a factor in the selectivity of the end-Cretaceous mass extinction, in which only neornithine dinosaurs survived.1 Although diet is directly documented in several early-diverging avian lineages,2 only a single specimen preserves evidence of diet in Enantiornithes, the dominant group of terrestrial Cretaceous birds.3 Morphology-based predictions suggest enantiornithines were faunivores,4,5,6 although the absence of evidence contrasts with the high preservation potential and relatively longer gut-retention times of these diets. Longipteryx is an unusual Early Cretaceous enantiornithine with an elongate rostrum; distally restricted dentition7; large, recurved, and crenulated teeth8; and tooth enamel much thicker than other paravians.9 Statistical analysis of rostral length, body size, and tooth morphology predicts Longipteryx was primarily insectivorous.4,5 Contrasting with these results, two new specimens of Longipteryx preserve gymnosperm seeds within the abdominal cavity interpreted as ingesta. Like Jeholornis, their unmacerated preservation and the absence of gastroliths indicate frugivory.10 As in Neornithes,11 complex diets driven by the elevated energetic demands imposed by flight, secondary rostral functions, and phylogenetic influence impede the use of morphological proxies to predict diet in early-diverging avian lineages.

2.
Dalton Trans ; 53(36): 15198-15204, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39221622

RESUMEN

The oxidation state (OS) holds significant importance in the field of chemistry and serves as a crucial parameter for tracking electrons. Lanthanide (Ln) elements predominately exhibit a +III oxidation state, with a few elements such as Ce, Pr, Nd, Tb, and Dy able to achieve a +IV oxidation state. Over the past century, numerous attempts to synthesize Pr(V) have been made without success until recent reports on Pr(V) oxides and nitride-oxide in the gas phase expanded our understanding of Ln elements. However, the formation of Pr(V) in the condensed phase remains an open question. In this work, based on advanced quantum chemical investigations, we predict that formation of the solid-state CsPrVF6 from Pr(III) and Pr(IV) complexes is exothermic, indicating that CsPrVF6 is stable. The crystal structure comprises [PrF6]- octahedral clusters occupying the interstitial spaces of Cs cations. Electronic structure analysis reveals that the CsPrF6 crystal has a closed-shell structure and that Pr reaches its highest oxidation state of +V. The results indicate that the existence of Pr(V) in solid-state Ln fluorides is not impossible, which enriches our understanding of high-valence Ln compounds.

3.
Sci Total Environ ; 952: 175991, 2024 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-39236814

RESUMEN

BACKGROUND: People are exposed to metals in various ways during their daily lives. However, the association between metal exposure and gallstones remains unclear. OBJECTIVES: To investigate the relationship between serum elemental concentrations and the risk of gallstones. METHODS: Participants (n = 4204) were drawn from the Henan Rural Cohort. Gallstone diagnosis was based on abdominal ultrasound reports during follow-up. Baseline serum elemental concentrations were measured using inductively coupled plasma mass spectrometry. The relationship between serum elemental levels and gallstones was evaluated using robust Poisson regression, restricted cubic spline (RCS), quantile g-computation (Qgcomp), grouped weighted quantile sum (GWQS) and Bayesian kernel machine regression (BKMR). RESULTS: 121 individuals were diagnosed with gallstone (incidence rate of 2.88 %). In robust Poisson regression, after adjusting for confounding factors, the highest quartile of arsenic concentration compared to the lowest quartile had a 1.90 times higher relative risk (RR) [95 % confidence interval (CI): 1.05, 3.44]. Conversely, the highest quartile of zinc concentration compared to the lowest quartile had a 0.50 times lower RR (95 % CI: 0.28, 0.89). RCS showed an approximately "S"-shaped nonlinear relationship between serum arsenic levels and gallstones, with increasing arsenic concentration leading to a higher risk of gallstones; however, the risk plateaued when arsenic concentration exceeded 0.62 µg/L. Both the Qgcomp and GWQS indicated that arsenic plays a significant role in increasing the risk of gallstones, whereas zinc plays a significant role in reducing the risk of gallstones. BKMR showed that raising arsenic exposure from the 25th to the 75th percentile increased the risk of gallstones, while raising serum zinc concentration reduced it. CONCLUSIONS: Higher serum arsenic concentration increases the risk of gallstones, whereas higher zinc concentration may reduce the risk. Effective prevention of gallstones may require further reduction of arsenic exposure and appropriate increases in zinc intake.


Asunto(s)
Arsénico , Exposición a Riesgos Ambientales , Cálculos Biliares , Humanos , Cálculos Biliares/epidemiología , Arsénico/sangre , China/epidemiología , Femenino , Persona de Mediana Edad , Masculino , Exposición a Riesgos Ambientales/estadística & datos numéricos , Población Rural/estadística & datos numéricos , Adulto , Estudios de Cohortes , Metales/sangre , Anciano , Factores de Riesgo
4.
Artículo en Inglés | MEDLINE | ID: mdl-39255183

RESUMEN

Differentiable architecture search (DARTS) has attracted much attention due to its simplicity and significant improvement in efficiency. However, the excessive accumulation of the skip connection, when training epochs become large, makes it suffer from weak stability and low robustness, thus limiting its practical applications. Many works have attempted to restrict the accumulation of skip connections by indicators or manual design. These methods, however, are susceptible to human priors and hyperparameters. In this work, we suggest a more subtle and direct approach that no longer explicitly searches for skip connections in the search stage, based on the paradox that skip connections were proposed to guarantee the performance of very deep networks, but the networks in the search stage of DARTS are actually very shallow. Instead, by introducing channel importance ranking and channel allocation strategy, the skip connections are implicitly searched and automatically refilled unimportant channels in the evaluation stage. Our method, dubbed adaptive channel allocation (ACA) strategy, is a general-purpose approach for DARTS, which universally works in DARTS variants without introducing human priors, indicators, or hyperparameters. Extensive experiments on various datasets and DARTS variants verify that the ACA strategy is the most effective one among the existing methods in improving robustness and dealing with the collapse issue when training epochs become large.

5.
Toxicol Appl Pharmacol ; 492: 117084, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39241930

RESUMEN

T-2 toxin, a highly toxic trichothecene mycotoxin widely found in food and feed, poses a significant threat to human health as well as livestock and poultry industry. Liver, being a crucial metabolic organ, is particularly susceptible to T-2 toxin induced damage characterized by inflammation and oxidative stress. Despite the role of Sirtuin 5 (SIRT5) in mitigating liver injury has been confirmed, its specific impact on T-2 toxin induced liver injury remains to be elucidated. The objective of this study was to investigate the protective role of SIRT5 against T-2 toxin induced liver injury in mice. Following the oral administration of 1 mg/kg.bw of T-2 toxin for 21 consecutive days to SIRT5 knockout (SIRT5-/-) and wild-type (WT) male mice, liver assessments were conducted. Our findings demonstrated that aggravated hepatic pathological injury was observed in SIRT5-/- mice, accompanied by elevated malondialdehyde (MDA) and Fe levels, as well as enhanced expression of glutathione peroxidase 4 (GPX4), NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), caspase-1, Gasdermin-D (GSDMD), tumour necrosis factor-alpha (TNF-α), and interleukin-1beta (IL-1ß). These results indicated that SIRT5 alleviated hepatic structural damage and dysfunction, while inhibiting oxidative stress, iron accumulation, and NLRP3 inflammasome activation. Analysis revealed a positive correlation among NLRP3 inflammasome activation, iron accumulation, and oxidative stress. Overall, our study demonstrated that SIRT5 mitigated liver injury induced by T-2 toxin through inhibiting iron accumulation, oxidative stress, and NLRP3 inflammasome activation, providing novel insights into the management and prevention of T-2 toxin poisoning.

6.
Phys Chem Chem Phys ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39263704

RESUMEN

Solution chemistry of actinide ions is critical to understanding the solvation behaviors and hydrolysis process. Using tetravalent thorium ion Th4+ as a representative example, we investigate the local structures and dynamic behaviors of hydrated Th4+ ions by ab initio molecular dynamics (AIMD) simulations using the recently developed norm-conserving pseudopotentials and basis sets optimized for actinides (J.-B. Lu et al., J. Chem. Theory Comput. 2021, 17, 3360-3371). AIMD simulations reveal two distinct solvation shells, with the first shell comprising 9 water molecules at approximately rTh-O = 2.50 Å and exhibiting a tricapped trigonal prism geometry. These conclusions are confirmed through metadynamics simulations and further structural analysis. AIMD simulations also show the slight effect of temperature and counterions on the structure of the solution. The structured solvation shells of the highly charged Th4+ ion with the specific geometry, distinct from the structure of liquid water, lead to corresponding structural changes in the hydrogen bond network in water. Additionally, beyond the solvent-shared ion pair (SIP) state observed in the unbiased AIMD simulations, the metadynamics simulations reconstruct a two-dimensional free energy surface that clearly indicates the potential stability of the contact ion pair (CIP) state in the system with Cl- as a counterion. The findings in this work provide insights into the solution chemistry of actinides and serve as a reference for studying other actinide solution systems.

7.
Redox Biol ; 75: 103291, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-39116526

RESUMEN

Modulation of immune microenvironment is critical for inflammatory bowel disease (IBD) intervention. Epigallocatechin gallate (EGCG), as a natural low toxicity product, has shown promise in treating IBD. However, whether and how EGCG regulates the intestinal microenvironment is not fully understood. Here we report that EGCG lessens colitis by orchestrating Th1 polarization and self-amplification in a novel manner that required multilevel-regulated intestinal microecosystem. Mechanistically, EGCG activates GPR43 on IEC to inhibit Th1 polarization dependently of short chain fatty acid (SCFA)-producing gut microbiota. Inhibition of GPR43 activity weakens the protective effects of EGCG on colitis development. Moreover, we confirm that fecal SCFAs and/or intestinal GPR43 are limited in patients with colitis and are correlated with Th1 cell number. Taken together, our study reveals an intestinal microenvironment-dependent immunoregulatory effects of EGCG in treating IBD and provides insight into mechanisms of EGCG-based novel immunotherapeutic strategies for IBD.


Asunto(s)
Catequina , Colitis , Microbioma Gastrointestinal , Receptores Acoplados a Proteínas G , Células TH1 , Catequina/análogos & derivados , Catequina/farmacología , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Ratones , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Colitis/metabolismo , Colitis/tratamiento farmacológico , Colitis/inmunología , Células TH1/inmunología , Células TH1/efectos de los fármacos , Células TH1/metabolismo , Humanos , Modelos Animales de Enfermedad , Ácidos Grasos Volátiles/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/microbiología
8.
Carbohydr Polym ; 343: 122428, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39174116

RESUMEN

Cadmium (Cd) removal from soil is crucial as Cd enters the food chain and affect food safety, thus impose severe threaten to human health. We developed PPC@PC-Fe, a dual-functional core-shell sphere for efficient soil Cd reduction. The shell (PPC) was composed of encapsulated citric acid (CA) in a polylactic acid (PLA) and polyethylene glycol (PEG) network, which endows a function of activating Cd; and the core (PC-Fe) consisted of a polyacrylic acid/carboxymethyl chitosan (PAA/CMC) hydrogel with Fe3O4 nanoparticles to adsorb adjacent activated Cd. Upon water contact, the shell dissolved, releasing CA to activate soil Cd. Simultaneously, the swellable PC-Fe core absorbed water and expanded in size, promoting the disintegration of PLA in the shell, which triggered the automatic separation of core from shell, enabling the exposed PC-Fe core to rapidly adsorb Cd. Furthermore, the PC-Fe core can be magnetically removed after adsorption of Cd. Soil culture tests showed that 2 % PPC@PC-Fe reduced soil Cd from 6.009 mg/kg to 4.834 mg/kg in 10 days, with the acid-soluble Cd being the predominantly target to be activated and remove. This study demonstrates an effective stepwise activation and adsorption mechanism by a single carrier, with simple magnetic collection minimizing secondary pollution. It offers an innovative approach to the remediation of cadmium-contaminated sites in the field.

9.
Proc Natl Acad Sci U S A ; 121(35): e2401916121, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39172788

RESUMEN

Soil organic carbon (SOC) is the largest carbon pool in terrestrial ecosystems and plays a crucial role in mitigating climate change and enhancing soil productivity. Microbial-derived carbon (MDC) is the main component of the persistent SOC pool. However, current formulas used to estimate the proportional contribution of MDC are plagued by uncertainties due to limited sample sizes and the neglect of bacterial group composition effects. Here, we compiled the comprehensive global dataset and employed machine learning approaches to refine our quantitative understanding of MDC contributions to total carbon storage. Our efforts resulted in a reduction in the relative standard errors in prevailing estimations by an average of 71% and minimized the effect of global variations in bacterial group compositions on estimating MDC. Our estimation indicates that MDC contributes approximately 758 Pg, representing approximately 40% of the global soil carbon stock. Our study updated the formulas of MDC estimation with improving the accuracy and preserving simplicity and practicality. Given the unique biochemistry and functioning of the MDC pool, our study has direct implications for modeling efforts and predicting the land-atmosphere carbon balance under current and future climate scenarios.


Asunto(s)
Carbono , Microbiología del Suelo , Suelo , Carbono/metabolismo , Carbono/análisis , Suelo/química , Incertidumbre , Cambio Climático , Ecosistema , Bacterias/metabolismo , Secuestro de Carbono , Aprendizaje Automático , Ciclo del Carbono
10.
Int J Biol Macromol ; 276(Pt 2): 133949, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39025172

RESUMEN

Different methods of starch modification have been proposed to broaden its application. In this study, the effects of ternary mixtures of natural crosslinking agents: chitosan-betaine-vanillin and gelatin-betaine-vanillin on the properties of pea starch were explored. These combinations of substances were selected because they have complementary crosslinking mechanisms. The effects of the ternary crosslinker mixtures on the gelatinization, mechanical properties, thermal stability, and microstructure of pea starch were compared. Both combinations of crosslinkers enhanced the gelatinization viscosity, viscoelasticity, gel hardness, and thermal stability of the pea starch, by an amount that depended on the ratio of the different components in the ternary mixtures. In all cases, the crystal structure of the starch granules disappeared after gelatinization. The modified starch had a more compact and uniform microstructure than the non-modified version, especially when it was crosslinked by vanillin, gelatin, and betaine. The improvement in the gelation properties of the starch were primarily attributed to hydrogen bonding, electrostatic attraction, and Schiff base crosslinking of the various components present. Gelatin enhanced the gel strength more than chitosan, which was probably because of greater hydrogen bonding. Our findings suggest that the properties of starch can be enhanced by adding ternary mixtures of natural crosslinkers.


Asunto(s)
Benzaldehídos , Betaína , Quitosano , Reactivos de Enlaces Cruzados , Gelatina , Pisum sativum , Almidón , Gelatina/química , Almidón/química , Quitosano/química , Betaína/química , Benzaldehídos/química , Pisum sativum/química , Reactivos de Enlaces Cruzados/química , Viscosidad , Geles/química
11.
Anal Biochem ; 694: 115626, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39032527

RESUMEN

Chimeric-antigen-receptor-T (CAR-T) have heralded a paradigm shift in the landscape of cancer immunotherapy. Retrovirus-mediated gene transfer serves to deliver the specific CAR expressing cassette into T cells across a spectrum of basic research and clinical contests in cancer therapy. However, it is necessary to devise a precise and validated quantitative methodology tailored to the diverse CAR constructs. In the investigation, a TaqMan real-time qPCR method was developed, utilizing primers targeting ψ gene sequence. This method offers a swift, sensitive, reproducible, and accurate tool for evaluating retroviral copy numbers at the integrated DNA level. Importantly, the established qPCR exhibits no cross-reactivity with non-transduced T cells or tissues. The regression equation characterizing TaqMan real-time PCR dynamics is y = -3.3841x + 41.402 (R2 = 0.999), showing an amplification efficiency of 97.47 %. Notably, the established qPCR method achieves a minimum detection of 43.1 copies/µL. Furthermore, both intra- and inter-group discrepancies remain below 4 %, underscoring the good repeatability of the established method. Our in vitro and in vivo results also support its sensitivity, specificity, and stability. Consequently, this method offers researchers with a cost-effective tool to quantify CAR copies both in vitro and in vivo.


Asunto(s)
Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Quiméricos de Antígenos , Linfocitos T , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Humanos , Receptores Quiméricos de Antígenos/genética , Linfocitos T/inmunología , Linfocitos T/metabolismo , Animales , Retroviridae/genética , Inmunoterapia Adoptiva/métodos , Ratones
12.
J Affect Disord ; 362: 502-509, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39025437

RESUMEN

BACKGROUND: Fewer studies have examined the relationship between air pollution and depressive or anxiety symptoms in rural residents. Social economic status (SES), as an important indicator of the current state of socioeconomic development, we know little about how it modifies the relationship between air pollution and symptoms of depression or anxiety. METHODS: The patient health questionnaire (PHQ-2) and generalized anxiety scale (GAD-2) were used to learn about the prevalence of depressive and anxiety symptoms, the social economic status of the participants was categorized into two levels: lower and higher, and a binary logistic regression model was used to analyze the relationship between air pollution and residents' symptoms of depression or anxiety. RESULTS: A total of 10,670 adults were enrolled in this study, of which a total of 1292 participants suffered from depressive symptoms and 860 suffered from anxiety symptoms. Short-term exposure to PM2.5 and O3, singly or in combination, may be associated with the onset of depression symptoms, and there was a significant interaction between SES and exposure to PM2.5 or O3. Residents of areas with higher SES may have a lower risk of suffering from anxiety symptoms after O3 exposure compared to participants living in lower SES. LIMITATIONS: The study was a cross-sectional study, which may have lowered the quality level of the evidence. CONCLUSIONS: Short-term PM2.5 and O3 exposure may be associated with an increased prevalence risk of depressive symptoms. Higher levels of SES may reduce the adverse effects of air pollution on depressive or anxiety symptoms.


Asunto(s)
Contaminación del Aire , Ansiedad , Depresión , Población Rural , Humanos , Femenino , Estudios Transversales , Masculino , China/epidemiología , Contaminación del Aire/efectos adversos , Contaminación del Aire/estadística & datos numéricos , Depresión/epidemiología , Depresión/psicología , Adulto , Población Rural/estadística & datos numéricos , Persona de Mediana Edad , Ansiedad/epidemiología , Ansiedad/psicología , Clase Social , Material Particulado/efectos adversos , Prevalencia , Ozono/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Anciano
13.
Chin J Cancer Res ; 36(3): 257-269, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38988490

RESUMEN

Objective: The open-label, phase II RATIONALE-209 study evaluated tislelizumab (anti-programmed cell death protein 1 antibody) as a tissue-agnostic monotherapy for microsatellite instability-high (MSI-H)/mismatch repair-deficient (dMMR) tumors. Methods: Adults with previously treated, locally advanced unresectable or metastatic MSI-H/dMMR solid tumors were enrolled. Patients received tislelizumab 200 mg intravenously every 3 weeks. Objective response rate (ORR; primary endpoint), duration of response (DoR), and progression-free survival (PFS) were assessed by independent review committee (Response Evaluation Criteria in Solid Tumors v1.1). Results: Eighty patients were enrolled and treated; 75 (93.8%) patients had measurable disease at baseline. Most had metastatic disease and received at least one prior therapy for advanced/metastatic disease (n=79; 98.8%). At primary analysis (data cutoff July 8, 2021; median follow-up 15.2 months), overall ORR [46.7%; 95% confidence interval (95% CI), 35.1-58.6; one-sided P<0.0001] and ORR across tumor-specific subgroups [colorectal (n=46): 39.1% (95% CI, 25.1-54.6); gastric/gastroesophageal junction (n=9): 55.6% (95% CI, 21.2-86.3); others (n=20): 60.0% (95% CI, 36.1-80.9)] were significantly greater with tislelizumab vs. a prespecified historical control ORR of 10%; five (6.7%) patients had complete responses. Median DoR, PFS, and overall survival were not reached with long-term follow-up (data cutoff December 5, 2022; median follow-up 28.9 months). Tislelizumab was well tolerated with no unexpected safety signals. Treatment-related adverse events (TRAEs) of grade ≥3 occurred in 53.8% of patients; 7.5% of patients discontinued treatment due to TRAEs. Conclusions: Tislelizumab demonstrated a significant ORR improvement in patients with previously treated, locally advanced unresectable or metastatic MSI-H/dMMR tumors and was generally well tolerated.

14.
Plant Physiol Biochem ; 214: 108926, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38996715

RESUMEN

Leucaena leucocephala (Leucaena) is a leguminous tree widely cultivated in tropical and subtropical regions due to its strong environmental suitability for abiotic stresses, especially drought. However, the molecular mechanisms and key pathways involved in Leucaena's drought response require further elucidation. Here, we comparatively analyzed the physiological and early transcriptional responses of Leucaena leaves and roots under drought stress simulated by polyethylene glycol (PEG) treatments. Drought stress induced physiological changes in Leucaena seedlings, including decreases in relative water content (RWC) and increases in relative electrolyte leakage (REL), malondialdehyde (MDA), proline contents as well as antioxidant enzyme activities. In response to drought stress, 6461 and 8295 differentially expressed genes (DEGs) were identified in the leaves and roots, respectively. In both tissues, the signaling transduction pathway of plant hormones was notably the most enriched. Specifically, abscisic acid (ABA) biosynthesis and signaling related genes (NCED, PP2C, SnRK2 and ABF) were strongly upregulated particularly in leaves. The circadian rhythm, DNA replication, alpha-linolenic acid metabolism, and secondary metabolites biosynthesis related pathways were repressed in leaves, while the glycolysis/gluconeogenesis and alpha-linolenic acid metabolism and amino acid biosynthesis processes were promoted in roots. Furthermore, heterologous overexpression of Leucaena drought-inducible genes (PYL5, PP2CA, bHLH130, HSP70 and AUX22D) individually in yeast increased the tolerance to drought and heat stresses. Overall, these results deepen our understanding of the tissue-specific mechanisms of Leucaena in response to drought and provide target genes for future drought-tolerance breeding engineering in crops.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Fabaceae/genética , Fabaceae/fisiología , Sequías , Perfilación de la Expresión Génica , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Estrés Fisiológico/genética , Transcriptoma
16.
Data Brief ; 55: 110582, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39006353

RESUMEN

Boiling is a high-performance heat dissipation process that is central to electronics cooling and power generation. However, there exists a practical limit of boiling heat transfer known as the critical heat flux (CHF), beyond which significant performance degradation is observed. Understanding the physical mechanism that triggers CHF is essential to meet the increasing cooling demands driven by power densification and device miniaturization. However, the high dimensionality, stochasticity, and dynamicity of the boiling process have led to strong challenges in the experimental characterization and modeling of boiling CHF. As such, high-frame rate, high-resolution, multi-physics boiling datasets are critical to advancing the fundamental understanding of boiling heat transfer. To this end, this paper presents a multimodal boiling dataset consisting of synchronized thermal, acoustic, and optical signals collected from five different heater surfaces under two distinct heat load conditions. With its high sampling frequency, diverse signal types, large data volume, and detailed recorded information, this dataset provides valuable "data blood" for the field of thermal crisis monitoring. This dataset will not only promote fundamental research on bubble dynamics during boiling but also support the implementation of advanced monitoring technologies in industrial applications such as power electronics, motors, data centers, and power plants.

17.
Glob Chang Biol ; 30(6): e17395, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38923190

RESUMEN

Soil microbes are essential for regulating carbon stocks under climate change. However, the uncertainty surrounding how microbial temperature responses control carbon losses under warming conditions highlights a significant gap in our climate change models. To address this issue, we conducted a fine-scale analysis of soil organic carbon composition under different temperature gradients and characterized the corresponding microbial growth and physiology across various paddy soils spanning 4000 km in China. Our results showed that warming altered the composition of organic matter, resulting in a reduction in carbohydrates of approximately 0.026% to 0.030% from humid subtropical regions to humid continental regions. These changes were attributed to a decrease in the proportion of cold-preferring bacteria, leading to significant soil carbon losses. Our findings suggest that intrinsic microbial temperature sensitivity plays a crucial role in determining the rate of soil organic carbon decomposition, providing insights into the temperature limitations faced by microbial activities and their impact on soil carbon-climate feedback.


Asunto(s)
Carbono , Cambio Climático , Microbiología del Suelo , Suelo , Temperatura , Suelo/química , Carbono/análisis , Carbono/metabolismo , China , Bacterias/metabolismo , Bacterias/crecimiento & desarrollo
18.
Inorg Chem ; 63(25): 11572-11582, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38866714

RESUMEN

Recently synthesized two-dimensional (2D) monolayer quasi-hexagonal-phase fullerene (qHPC60) demonstrates excellent thermodynamic stability. Within this monolayer, each fullerene cluster is surrounded by six adjacent C60 cages along an equatorial plane and is connected by both C-C single bonds and [2 + 2] cycloaddition bonds that serve as bridges. In this study, we investigate the stability mechanism of the 2D qHPC60 monolayer by examining the electronic structure and chemical bonding through state-of-the-art theoretical methodologies. Density functional theory (DFT) studies reveal that 2D qHPC60 possesses a moderate direct electronic band gap of 1.46 eV, close to the experimental value (1.6 eV). It is found that the intermolecular bridge bonds play a crucial role in enhancing the charge flow and redistribution among C60 cages, leading to the formation of dual π-aromaticity within the C60 sphere and stabilizing the 2D framework structure. Furthermore, we identify a series of delocalized superatom molecular orbitals (SAMOs) within the 2D qHPC60 monolayer, exhibiting atomic orbital-like behavior and hybridization to form nearly free-electron (NFE) bands with σ/π bonding and σ*/π* antibonding properties. Our findings provide insights into the design and potential applications of NFE bands derived from SAMOs in 2D qHPC60 monolayers.

19.
J Chem Phys ; 160(23)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38884396

RESUMEN

The advent of Neural-network Quantum States (NQS) has significantly advanced wave function ansatz research, sparking a resurgence in orbital space variational Monte Carlo (VMC) exploration. This work introduces three algorithmic enhancements to reduce computational demands of VMC optimization using NQS: an adaptive learning rate algorithm, constrained optimization, and block optimization. We evaluate the refined algorithm on complex multireference bond stretches of H2O and N2 within the cc-pVDZ basis set and calculate the ground-state energy of the strongly correlated chromium dimer (Cr2) in the Ahlrichs SV basis set. Our results achieve superior accuracy compared to coupled cluster theory at a relatively modest CPU cost. This work demonstrates how to enhance optimization efficiency and robustness using these strategies, opening a new path to optimize large-scale restricted Boltzmann machine-based NQS more effectively and marking a substantial advancement in NQS's practical quantum chemistry applications.

20.
Carbohydr Polym ; 341: 122348, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38876718

RESUMEN

Antibiotic abuse is increasing the present rate of drug-resistant bacterial wound infections, producing a significant healthcare burden globally. Herein, we prepared a pH-responsive CMCS/PVP/TA (CPT) multifunctional hydrogel dressing by embedding the natural plant extract TA as a nonantibiotic and cross-linking agent in carboxymethyl chitosan (CMCS) and polyvinylpyrrolidone (PVP) to prompt wound healing. The CPT hydrogel demonstrated excellent self-healing, self-adaptive, and adhesion properties to match different wound requirements. Importantly, this hydrogel showed pH sensitivity and exhibited good activity against resistant bacteria and antioxidant activity by releasing TA in case of bacterial infection (alkaline). Furthermore, the CPT hydrogel exhibited coagulant ability and could rapidly stop bleeding within 30 s. The biocompatible hydrogel effectively accelerated wound healing in a full-thickness skin defect model by thickening granulation tissue, increasing collagen deposition, vascular proliferation, and M2-type macrophage polarization. In conclusion, this study demonstrates that multifunctional CPT hydrogel offers a candidate material with potential applications for infected skin wound healing.


Asunto(s)
Antibacterianos , Vendajes , Quitosano , Hidrogeles , Cicatrización de Heridas , Quitosano/química , Quitosano/análogos & derivados , Quitosano/farmacología , Quitosano/síntesis química , Cicatrización de Heridas/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Hidrogeles/síntesis química , Animales , Concentración de Iones de Hidrógeno , Ratones , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Povidona/química , Masculino , Staphylococcus aureus/efectos de los fármacos , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química , Piel/efectos de los fármacos , Piel/patología
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