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1.
Nano Lett ; 24(3): 1001-1008, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38198561

RESUMEN

We report a zero-dimensional (0D) lead-free chiral perovskite (S-/R-MBA)4Bi2I10 with a high degree of circularly polarized light (CPL) emission. Our 0D lead-free chiral perovskite exhibits an average degree of circular polarization (DOCP) of 19.8% at 78 K under linearly polarized laser excitation, and the maximum DOCP can reach 25.8%, which is 40 times higher than the highest DOCP of 0.5% in all reported lead-free chiral perovskites to the best of our knowledge. The high DOCP of (S-/R-MBA)4Bi2I10 is attributed to the free exciton emission with a Huang-Rhys factor of 2.8. In contrast, all the lead-free chiral perovskites in prior reports are dominant by self-trapped exciton in which the spin relaxation reduces DOCP dramatically. Moreover, we realize the manipulation of the valley degree of freedom of monolayer WSe2 by using the spin injection of the 0D chiral lead-free perovskites. Our results provide a new perspective to develop lead-free chiral perovskite devices for CPL light source, spintronics, and valleytronics.

2.
Nano Lett ; 22(17): 7230-7237, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36036787

RESUMEN

Interlayer excitons (IXs) in type II van der Waals (vdW) heterostructures are equipped with an oriented permanent dipole moment and long lifetime and thus would allow promising applications in excitonic and optoelectronic devices. However, based on the widely studied heterostructures of transition-metal dichalcogenides (TMDs), IX emission is greatly influenced by the lattice mismatch and geometric misalignment between the constituent layers, increasing the complexity of the device fabrication. Here, we report on the robust momentum-indirect IX emission in TMD/two-dimensional (2D) perovskite vdW heterostructures, which were fabricated without considering the orientation arrangement or momentum mismatch. The IXs show a large diffusion coefficient of ∼10 cm2 s-1, and importantly the IX emission energy can be widely tuned from 1.3 to 1.6 eV via changing the layer number of the 2D perovskite or the thickness of TMD flakes, shedding light on the applications of vdW interface engineering to broad-spectrum optoelectronics.

3.
Ann N Y Acad Sci ; 1532(1): 18-36, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38152040

RESUMEN

Eye movements have been extensively studied with respect to visual stimulation. However, we live in a multisensory world, and how the eyes are driven by other senses has been explored much less. Here, we review the evidence on how audition can trigger and drive different eye responses and which cortical and subcortical neural correlates are involved. We provide an overview on how different types of sounds, from simple tones and noise bursts to spatially localized sounds and complex linguistic stimuli, influence saccades, microsaccades, smooth pursuit, pupil dilation, and eye blinks. The reviewed evidence reveals how the auditory system interacts with the oculomotor system, both behaviorally and neurally, and how this differs from visually driven eye responses. Some evidence points to multisensory interaction, and potential multisensory integration, but the underlying computational and neural mechanisms are still unclear. While there are marked differences in how the eyes respond to auditory compared to visual stimuli, many aspects of auditory-evoked eye responses remain underexplored, and we summarize the key open questions for future research.


Asunto(s)
Movimientos Oculares , Movimientos Sacádicos , Humanos , Estimulación Luminosa/métodos , Potenciales Evocados Auditivos , Percepción Auditiva
4.
Front Immunol ; 15: 1373371, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38686375

RESUMEN

Background: Serum creatinine (Cr) and albumin (Alb) are important predictors of mortality in individuals with various diseases, including acute pancreatitis (AP). However, most previous studies have only examined the relationship between single Cr or Alb levels and the prognosis of patients with AP. To our knowledge, the association between short- and long-term all-cause mortality in patients with AP and the blood creatinine to albumin ratio (CAR) has not been investigated. Therefore, this study aimed to evaluate the short- and long-term relationships between CAR and all-cause mortality in patients with AP. Methods: We conducted a retrospective study utilizing data from the Medical Information Market for Intensive Care (MIMIC-IV) database. The study involved analyzing various mortality variables and obtaining CAR values at the time of admission. The X-tile software was used to determine the optimal threshold for the CAR. Kaplan-Meier (K-M) survival curves and multivariate Cox proportional hazards regression models were used to assess the relationship between CAR and both short- and long-term all-cause mortality. The predictive power, sensitivity, specificity, and area under the curve (AUC) of CAR for short- and long-term mortality in patients with AP after hospital admission were investigated using Receiver Operating Characteristic analysis. Additionally, subgroup analyses were conducted. Results: A total of 520 participants were included in this study. The CAR ideal threshold, determined by X-tile software, was 0.446. The Cox proportional hazards model revealed an independent association between CAR≥0.446 and all-cause mortality at 7-day (d), 14-d, 21-d, 28-d, 90-d, and 1-year (y) before and after adjustment for confounders. K-M survival curves showed that patients with CAR≥0.446 had lower survival rates at 7-d, 14-d, 21-d, 28-d, 90-d, and 1-y. Additionally, CAR demonstrated superior performance, with higher AUC values than Cr, Alb, serum total calcium, Glasgow Coma Scale, Systemic Inflammatory Response Syndrome score, and Sepsis-related Organ Failure Assessment score at 7-d, 14-d, 21-d, 28-d, 90-d, and 1-y intervals. Subgroup analyses showed that CAR did not interact with a majority of subgroups. Conclusion: The CAR can serve as an independent predictor for short- and long-term all-cause mortality in patients with AP. This study enhances our understanding of the association between serum-based biomarkers and the prognosis of patients with AP.


Asunto(s)
Creatinina , Unidades de Cuidados Intensivos , Pancreatitis , Albúmina Sérica , Humanos , Masculino , Pancreatitis/mortalidad , Pancreatitis/sangre , Pancreatitis/diagnóstico , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Creatinina/sangre , Anciano , Pronóstico , Albúmina Sérica/análisis , Biomarcadores/sangre , Bases de Datos Factuales , Adulto
5.
Sci Rep ; 14(1): 16749, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033195

RESUMEN

The triglyceride-glucose (TyG) index is a novel marker of insulin resistance that has been strongly associated with many diseases related to metabolic disorders, such as diabetes, coronary heart disease, myocardial infarction, obesity, nonalcoholic fatty liver disease, and stroke. However, whether the TyG index is associated with the prevalence of gallstones has not been determined. Therefore, the purpose of this study was to evaluate the relationship between the TyG index and the prevalence of gallstones in American adults, as well as the age at which adults in America undergo their first gallstone surgery. We selected individuals from the National Health and Nutrition Examination Survey (NHANES) database from 2017 to March 2020. Based on the goal of our study, comprehensive inclusion and exclusion criteria were created. A logistic regression analysis, dose-response curve, and subgroup analysis were computed to assess the relationship between the TyG index and gallstone prevalence and age at first surgery for gallstone. A total of 3905 participants aged > 20 years were included in our study, of whom 421 had a self-reported history of gallstones. A total of 1884 (48.2%) males and 2021 (51.8%) females were included. After confounders adjustment, it was found single-unit increases in the TyG index were linked with a 25.0% increase in gallstone prevalence (odds ratio [OR] = 1.25, 95% confidence interval [95%CI]: 1.04, 1.51). After conversion of the TyG index values from continuous to categorical variables with tertiles, a marked 48% increase in gallstone incidence was found in tertile 3 relative to tertile 1 (OR = 1.48, 95% CI: 1.09, 1.99). The dose-response curve results indicated positive associations between gallstone prevalence and the TyG index, while the latter was negatively associated with age at first gallstone surgery. Based on subgroup analysis, the positive association between TyG index and high-incidence of gallstones was more significant in females (OR = 1.39, 95% CI: 1.09, 1.77), age < 40 years (OR = 2.02, 95% CI: 1.23, 3.29), and other race (OR = 1.46, 95% CI: 1.06, 2.02). A higher TyG index is associated with a higher incidence of gallstones and may lead to an earlier age of first gallstone surgery. However, a causal relationship between TyG and gallstones cannot be established.


Asunto(s)
Glucemia , Cálculos Biliares , Triglicéridos , Humanos , Cálculos Biliares/cirugía , Cálculos Biliares/epidemiología , Cálculos Biliares/sangre , Femenino , Masculino , Adulto , Triglicéridos/sangre , Persona de Mediana Edad , Prevalencia , Estados Unidos/epidemiología , Glucemia/análisis , Glucemia/metabolismo , Encuestas Nutricionales , Anciano , Factores de Edad , Adulto Joven , Resistencia a la Insulina
6.
Materials (Basel) ; 16(24)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38138696

RESUMEN

Due to their distinct physical, chemical, and mechanical features, high-entropy alloys have significantly broadened the possibilities of designing metal materials, and are anticipated to hold a crucial position in key engineering domains such as aviation and aerospace. The fatigue performance of high-entropy alloys is a crucial aspect in assessing their applicability as a structural material with immense potential. This paper provides an overview of fatigue experiments conducted on high-entropy alloys in the past two decades, focusing on crack initiation behavior, crack propagation modes, and fatigue life prediction models.

7.
Carbohydr Polym ; 303: 120481, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36657852

RESUMEN

Polysaccharides were the key ingredients of many herbal medicines, and were responsible for multiple pharmacological activities. In this study, a novel polysaccharide fraction, named SLP-2, was isolated from Stauntonia leucantha fruits, and purified by DEAE-52 and Sephadex G-100 column chromatography. Furthermore, SLP-2 was identified by congo red, methylation, partial acid hydrolysis and NMR. The results indicated that the backbone of SLP-2 was composed of →4)-ß-D-Galp-(1 â†’ 4)-ß-D-Galp-(1→ substituted at C-6 with 1,5-linked arabinan. SLP-2 had good anti-oxidation ability in vitro. Surprisingly, we found that reduction of carboxyl groups and methylation of hydroxyl groups enhanced the ability to scavenge 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radicals and inhibit lipid peroxidation, and weakened the activity to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and reduce ferric iron.


Asunto(s)
Frutas , Galactanos , Galactanos/química , Polisacáridos/química , Antioxidantes/química , Oxidación-Reducción
8.
Mol Biomed ; 4(1): 16, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37211575

RESUMEN

SARS-CoV-2 and its variants, with the Omicron subvariant XBB currently prevailing the global infections, continue to pose threats on public health worldwide. This non-segmented positive-stranded RNA virus encodes the multi-functional nucleocapsid protein (N) that plays key roles in viral infection, replication, genome packaging and budding. N protein consists of two structural domains, NTD and CTD, and three intrinsically disordered regions (IDRs) including the NIDR, the serine/arginine rich motif (SRIDR), and the CIDR. Previous studies revealed functions of N protein in RNA binding, oligomerization, and liquid-liquid phase separation (LLPS), however, characterizations of individual domains and their dissected contributions to N protein functions remain incomplete. In particular, little is known about N protein assembly that may play essential roles in viral replication and genome packing. Here, we present a modular approach to dissect functional roles of individual domains in SARS-CoV-2 N protein that reveals inhibitory or augmented modulations of protein assembly and LLPS in the presence of viral RNAs. Intriguingly, full-length N protein (NFL) assembles into ring-like architecture whereas the truncated SRIDR-CTD-CIDR (N182-419) promotes filamentous assembly. Moreover, LLPS droplets of NFL and N182-419 are significantly enlarged in the presence of viral RNAs, and we observed filamentous structures in the N182-419 droplets using correlative light and electron microscopy (CLEM), suggesting that the formation of LLPS droplets may promote higher-order assembly of N protein for transcription, replication and packaging. Together this study expands our understanding of the multiple functions of N protein in SARS-CoV-2.

9.
Front Surg ; 9: 860857, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35478725

RESUMEN

Background: Necroptosis is associated with the development of many tumors but in bladder cancer the tumor microenvironment (TME) and prognosis associated with necroptosis is unclear. Methods: We classified patients into different necroptosis subtypes by the expression level of NRGS (necroptosis-related genes) and analyzed the relationship between necroptosis subtypes of bladder cancer and TME, then extracted differentially expressed genes (DEGS) of necroptosis subtypes, classified patients into different gene subtypes according to DEGS, and performed univariate COX analysis on DEGS to obtain prognosis-related DEGS. All patients included in the analysis were randomized into the Train and Test groups in a 1:1 ratio, and the prognostic model was obtained using the LASSO algorithm and multivariate COX analysis with the Train group as the sample, and external validation of the model was conducted using the GSE32894. Results: Two necroptosis subtypes and three gene subtypes were obtained by clustering analysis and the prognosis-related DEGS was subjected to the LASSO algorithm and multivariate COX analysis to determine six predictors to construct the prognostic model using the formula: riskScore = CERCAM × 0.0035 + POLR1H × -0.0294 + KCNJ15 × -0.0172 + GSDMB × -0.0109 + EHBP1 × 0.0295 + TRIM38 × -0.0300. The results of the survival curve, roc curve, and risk curve proved the reliability of the prognostic model by validating the model with the test group and the results of the calibration chart of the Nomogram applicable to the clinic also showed its good accuracy. Necroptosis subtype A with high immune infiltration had a higher risk score than necroptosis subtype B, gene subtype B with low immune infiltration had a lower risk score than gene subtypes A and C, CSC index was negatively correlated with the risk score and drug sensitivity prediction showed that commonly used chemotherapeutic agents were highly sensitive to the high-risk group. Conclusion: Our analysis of NRGS in bladder cancer reveals their potential role in TME, immunity, and prognosis. These findings may improve our understanding of necroptosis in bladder cancer and provide some reference for predicting prognosis and developing immunotherapies.

10.
J Drug Target ; 30(4): 442-449, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34844491

RESUMEN

Until now, the metabolic effects of hepatitis B virus (HBV) replication on the progression of hepatic diseases (hepatitis, cirrhosis, and liver cancer) and liver functions have remained unexplored. Thus, a total of 199 hepatic disease patients with active and inactive HBV were enrolled in this study to explore serum metabolic characteristics using untargeted metabolomics. Multiple analyses, including principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), volcano plot and pathway analysis, were used for metabolic data analysis. Additionally, differential metabolites were analysed by commercial databases. A decrease of approximately 0.8-fold in amino acids (L-glutamic acid, D-glutamine and L-tyrosine) and an increase of 2-fold in phosphatidylcholines (PCs) and lysophosphatidylcholines (LPCs) were observed in hepatic disease patients with HBV replication. Moreover, downregulation of arachidonic acid, PC 34:2, sn-glycerol-3-phosphocholine, 1-palmitoylglycerophosphoinositol, and 1-oleoylglycerophosphoinositol by 0.6-fold was also found in the serum of patients with HBV replication. In addition, liver function was significantly different between cirrhosis patients with or without HBV replication (p < .05). In summary, this is the first study to focus on the metabolic changes induced by HBV replication in patients and to compare metabolic alterations in the progression of hepatic disease induced by HBV infection. High levels of amino acid depletion and PC and LPC biosynthesis were primarily observed, which may shed new light on the pathogenesis and treatment of HBV infection.


Asunto(s)
Hepatitis B Crónica , Hepatitis B , Hepatitis B/complicaciones , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/metabolismo , Humanos , Cirrosis Hepática , Metabolómica , Replicación Viral
11.
Micromachines (Basel) ; 12(11)2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34832724

RESUMEN

The diameter of most blood vessels in cardiovascular and peripheral vascular system is less than 6 mm. Because the inner diameter of such vessels is small, a built-in stent often leads to thrombosis and other problems. It is an important goal to replace it directly with artificial vessels. This paper creatively proposed a preparation method of a small-diameter artificial vascular graft which can form a controllable microstructure on the inner wall and realize a multi-material composite. On the one hand, the inner wall of blood vessels containing direct writing structure is constructed by electrostatic direct writing and micro-imprinting technology to regulate cell behavior and promote endothelialization; on the other hand, the outer wall of blood vessels was prepared by electrospinning PCL to ensure the stability of mechanical properties of composite grafts. By optimizing the key parameters of the graft, a small-diameter artificial blood vessel with controllable microstructure on the inner wall is finally prepared. The corresponding performance characterization experimental results show that it has advantages in structure, mechanical properties, and promoting endothelialization.

12.
Int J Bioprint ; 7(1): 299, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33585709

RESUMEN

Three-dimensional (3D) bioprinting is an important technology for fabricating artificial tissue. To effectively reconstruct the multiscale structure and multi-material gradient of natural tissues and organs, 3D bioprinting has been increasingly developed into multi-process composite mode. The current 3D composite bioprinting is a combination of two or more printing processes, and oftentimes, physical field regulation that can regulate filaments or cells during or after printing may be involved. Correspondingly, both path planning strategy and process control all become more complex. Hence, the computer-aided design and computer-aided manufacturing (CAD/CAM) system that is traditionally used in 3D printing system is now facing challenges. Thus, the scale information that cannot be modeled in the CAD process should be considered in the design of CAM by adding a process management module in the traditional CAD/CAM system and add more information reflecting component gradient in the path planning strategy.

13.
Chem Commun (Camb) ; 55(96): 14490-14493, 2019 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-31729522

RESUMEN

A biomimetic CoPe@CdS/rGO hybrid that self-assembles via the integration of a molecular cobalt catalyst and CdS nano-semiconductor on reduced graphene oxide was constructed for boosting photocatalytic H2 production. Photoinduced electron transfer from CdS/rGO to the molecular catalyst occurs and a long-lived charge-separation state forms for high H2 production.

14.
ChemSusChem ; 12(20): 4617-4622, 2019 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-31448535

RESUMEN

Surface ligand-removed and Cd-rich CdSe quantum dots (QDs) exhibited exceptional activity as photocatalyst for the conversion of CO2 to CO. A CO production rate up to 789 mmol g-1 h-1 was achieved in a triethylamine/dimethylformamide mixture under visible-light irradiation. Mechanistic studies revealed that improving the Cd/Se stoichiometric ratio and exposing more active surface Cd atoms significantly enhanced the activity of CdSe QDs for CO2 photoreduction.

15.
Dalton Trans ; 47(37): 13142-13150, 2018 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-30168831

RESUMEN

The conversion of carbon dioxide (CO2) to fuels or value-added chemicals by a photocatalytic system has recently been of growing research interest. One of the challenges is the development of new catalysts with high activity and low cost. Cobalt complexes have long been used as catalysts for the reduction of CO2 in either electrochemical or photochemical systems. Recently, a series of cis-CoII complexes of tetradentate pyridine-amine ligands (N4-ligands) exhibited high activity in the reduction of CO2 in homogeneous photocatalytic systems. However, only CO was obtained as the reduction product. In this regard, herein, we report a novel cis-CoII complex C1 supported by an N4 ligand derivatized with TPA (TPA = tris(2-pyridylmethyl)amine). In contrast to the aforementioned CoII catalysts, which contain two halogen atoms at cis-positions, C1 contains one oxygen atom at one cis-coordination site. The structure of C1 was fully characterized by MS, elemental analysis, and single-crystal X-ray diffraction. Experiments on the photocatalytic reduction of CO2 revealed that C1 is able to convert CO2 to not only CO but also formate in a homogeneous system containing C1 as a catalyst, Ir(ppy)3 as a photosensitizer, and triethylamine as an electron donor under visible-light irradiation. The catalytic activity and distribution of reduction products of this system are highly affected by the solvent environment. The presence of water in this system enhances the efficiency of 2H+-to-H2 and CO2-to-formate conversions. Electrochemical and steady-state emission quenching experiments indicate that photoinduced electron transfer from excited Ir(ppy)3 to C1 is thermodynamically feasible. A photogenerated CoI species is suggested to be the active species involved in the reduction of CO2 and protons. DFT calculations were performed to elucidate the catalytic pathways of the formation of CO, formate, and H2 in this system; four pathways, namely, one for the formation of CO, one for the formation of hydrogen, and two for the formation of formate, were suggested. The results revealed that the oxygen atom at the cis-coordination site in C1 plays an important role in stabilizing the transition state during the transformation of CO2 at the cobalt center.

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