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1.
Chem Sci ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39129778

RESUMEN

Single cell amperometry has proven to be a powerful and well-established method for characterizing single vesicular exocytotic events elicited at the level of excitable cells under various experimental conditions. Nevertheless, most of the reported characteristics are descriptive, being mostly concerned with the morphological characteristics of the recorded current spikes (maximum current intensities, released charge, rise and fall times, etc.) which are certainly important but do not provide sufficient kinetic information on exocytotic mechanisms due to lack of quantitative models. Here, continuing our previous efforts to provide rigorous models rationalizing the kinetic structures of frequently encountered spike types (spikes with unique exponential decay tails and kiss-and-run events), we describe a new theoretical approach enabling a quantitative kinetic modeling of all types of exocytotic events giving rise to current spikes exhibiting exponential decay tails. This model follows directly from the fact that the condensation of long intravesicular polyelectrolytic strands by high concentrations of monocationic neurotransmitter molecules leads to a matrix structure involving two compartments in constant kinetic exchanges during release. This kinetic model has been validated theoretically (direct and inverse problems) and its experimental interest established by the analysis of the amperometric spikes relative to chromaffin and PC12 cells previously published by some of us.

2.
Gerontology ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39097967

RESUMEN

OBJECTIVE: Examining the relationship between the plant-based dietary index and vision impairment (VI), hearing impairment (HI), and dual sensory impairment (DSI) among Chinese aged 65 and older. METHODS: Based on the 2018 data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), a cross-sectional study was conducted on 14,859 samples. The assessment of dietary quality utilized the Plant-Based Diet Index (PDI), Healthy Plant-Based Diet Index (hPDI), and Unhealthy Plant-Based Diet Index (uPDI). Logistic regression analysis was used to examine the associations between PDIs and sensory impairments. Additionally, restricted cubic spline analysis was utilized to investigate the non-linear association between PDIs and sensory impairments. RESULTS: Participants in the highest quintile of PDI exhibited reduced prevalence of VI (OR 0.78, 95% CI:0.67-0.90, Ptrend <0.001), HI (OR 0.83, 95% CI:0.70-0.99, Ptrend <0.001) and DSI (OR 0.62, 95%CI:0.51-0.77, Ptrend <0.001) relative to those in the lowest quintile. Moreover, individuals who ranked in the highest quintile for hPDI exhibited a 25% reduced risk of VI disease. Conversely, those in the highest quintile of uPDI were associated with increased prevalence of VI (OR 1.37, 95% CI: 1.17-1.61, Ptrend <0.001), HI (OR 1.36, 95% CI: 1.12-1.65, Ptrend <0.001) and DSI (OR 1.56, 95% CI: 1.25-1.95, Ptrend <0.001). The relationship between PDIs increasing by every 10 units and sensory impairments showed similar patterns. Notably, hPDI demonstrated a non-linear relationship with HI (Pfor nonlinearity = 0.001), while the others exhibited linear associations. CONCLUSION: The increase in PDI and hPDI correlates with a reduced prevalence of one or more sensory impairments. Conversely, an increase in uPDI is associated with an elevated prevalence of multiple sensory impairments. Our study findings emphasize the significance of plant-based food quality, advocating for adherence to a plant-based dietary pattern while reducing the intake of less healthy plant foods and animal-based products.

3.
Chem Sci ; 15(31): 12264-12269, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39118606

RESUMEN

Metal oxides are promising (photo)electrocatalysts for sustainable energy technologies due to their good activity and abundant resources. Their applications such as photocatalytic water splitting predominantly involve aqueous interfaces under electrochemical conditions, but in situ probing oxide-water interfaces is proven to be extremely challenging. Here, we present an electrochemical scanning tunneling microscopy (EC-STM) study on the rutile TiO2(110)-water interface, and by tuning surface redox chemistry with careful potential control we are able to obtain high quality images of interfacial structures with atomic details. It is interesting to find that the interfacial water exhibits an unexpected double-row pattern that has never been observed. This finding is confirmed by performing a large scale simulation of a stepped interface model enabled by machine learning accelerated molecular dynamics (MLMD) with ab initio accuracy. Furthermore, we show that this pattern is induced by the steps present on the surface, which can propagate across the terraces through interfacial hydrogen bonds. Our work demonstrates that by combining EC-STM and MLMD we can obtain new atomic details of interfacial structures that are valuable to understand the activity of oxides under realistic conditions.

4.
Angew Chem Int Ed Engl ; : e202413246, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39166346

RESUMEN

Contact Electro-Catalysis (CEC) using commercial dielectric materials in contact-separation cycles with water triggers interfacial electron transfer, generating reactive oxygen species (ROS). However, the hydrophobicity of these materials limits reaction sites, and the generated ROS often combine to form hydrogen peroxide (H2O2), which does not decompose further, leading to suboptimal rates. Addressing H2O2 generation and activation is crucial for advancing CEC. Here, we synthesized a catalyst by loading polytetrafluoroethylene (PTFE) onto ZSM-5 (PZ), achieving uniform dispersion in water. Introducing an FeIII-initiated self-cycling Fenton system (SF-CEC), with synergistic O2 activation and FeIII-activated H2O2, enhanced ROS generation. This system enabled nearly 99% degradation of azo dyes within 10 minutes, a sixfold improvement over traditional CEC. It represents the fastest ultrasound-induced degradation rate of methyl orange dye to date. Without extra oxidants, it also achieved stable dissolution of precious metals in weakly acidic solutions at room temperature, with 80% gold dissolution within 2 hours-2.5 times faster than similar systems. This study corrects the perception of CEC under acidic conditions, offering new insights for dye degradation and precious metal recovery.

5.
Vascular ; : 17085381241274556, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39132764

RESUMEN

OBJECTIVE: To evaluate the safety and efficacy of pharmacomechanical thrombectomy and catheter-directed thrombolysis (CDT) as approaches to treating deep venous thrombosis of lower extremities (LEDVT). METHODS: The PubMed, Web of Science, Wanfang, Embase, Chinese Science and Technology Journal, Cochrane, and China National Knowledge Infrastructure (CNKI) databases were systematically searched for relevant articles published through October 2023, after which appropriate inclusion and exclusion criteria were used to screen out relevant articles. Review Manager 5.4.1 was used to extract key data from these studies, and pooled analyses were conducted based on mead difference (MD) or odds ratio (OR) values and corresponding 95% confidence interval (CI). Study quality was assessed with the Newcastle-Ottawa scale. TRIAL REGISTRATION: This study has been registered at INPLASY.COM (No. INPLASY2023100075). RESULTS: In total, 31 relevant studies enrolling 2413 patients were included in this meta-analysis, with 1184 and 1229 patients in the AngioJet and CDT groups, respectively. These analyses revealed that the AngioJet group exhibited significantly higher rates of early postoperative deep vein patency (MD = 7.73, 95% CI (3.29, 12.17), p = .0006) and affected limb symptom improvement (MD = 6.31, 95% CI (1.82,10.80), p = .006) relative to the CDT group, whereas no differences in grade II or III thrombus clearance rates (OR = 1.30, 95% CI (0.95, 1.77), p = .10) or changes in thigh circumference before and after treatment (MD = 0.01, 95% CI (-0.80, 0.83), p = .97) were observed. The AngioJet group also exhibited lower urokinase doses (MD = -145.33, 95% CI (-164.28,126.38), p < .00001), shorter thrombolysis time (MD = -2.35, 95% CI(-2.80, -1.90), p < .00001), a less prolonged hospital stay (MD = -3.13, 95% CI(-3.81, -2.45), p < .00001), lower rates of PTS incidence (OR = 0.56, 95% CI(0.36, 0.88), p = .01), and reduced complication rates (OR = 0.51, 95% CI(0.31, 0.83), p = .0007). CONCLUSION: Studies published to date suggest that relative to CDT treatment, pharmacomechanical thrombectomy is associated with improved thrombus clearance, fewer complications, and lower complication rates in LEDVT patients, underscoring the safety and efficacy of this therapeutic strategy.

6.
J Phys Chem Lett ; 15(32): 8233-8239, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39102567

RESUMEN

The microscopic structure of the material's solid-liquid interface significantly influences its physicochemical properties. Peak force infrared microscopy (PFIR) is a powerful technique for analyzing these interfaces at the nanoscale, revealing crucial structure-activity relationships. PFIR is recognized for its explicit photothermal signal generation mechanism but tends to overlook other photoinduced forces, which can disturb the obtained infrared spectra, thereby reducing spectral signal-to-noise ratio (SNR) and sensitivity. We have developed a multiphysics-coupled theoretical model to assess the magnitudes of various photoinduced forces in PFIR experiments and have found that the magnitude of the photoacoustic force is comparable to that of the photothermal expansion force in a liquid environment. Our calculations show that through simple modulation of the pulse waveform it is possible to effectively suppress the photoacoustic interference, thereby improving the SNR and sensitivity of PFIR. This work aims to alert researchers to the potential for strong photoacoustic interference in liquid-phase PFIR measurements and enhance the performance of PFIR by clarifying the photoinduced forces entangled in the signals.

7.
Light Sci Appl ; 13(1): 166, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39009583

RESUMEN

3-dB couplers, which are commonly used in photonic integrated circuits for on-chip information processing, precision measurement, and quantum computing, face challenges in achieving robust performance due to their limited 3-dB bandwidths and sensitivity to fabrication errors. To address this, we introduce topological physics to nanophotonics, developing a framework for topological 3-dB couplers. These couplers exhibit broad working wavelength range and robustness against fabrication dimensional errors. By leveraging valley-Hall topology and mirror symmetry, the photonic-crystal-slab couplers achieve ideal 3-dB splitting characterized by a wavelength-insensitive scattering matrix. Tolerance analysis confirms the superiority on broad bandwidth of 48 nm and robust splitting against dimensional errors of 20 nm. We further propose a topological interferometer for on-chip distance measurement, which also exhibits robustness against dimensional errors. This extension of topological principles to the fields of interferometers, may open up new possibilities for constructing robust wavelength division multiplexing, temperature-drift-insensitive sensing, and optical coherence tomography applications.

9.
J Colloid Interface Sci ; 674: 766-777, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38955008

RESUMEN

Plasmon-mediated chemical reactions (PMCR) have garnered growing interest as a promising concept for photocatalysis. However, in electrochemical systems at solid-liquid interfaces, the photo-induced charge transfer on the surface of metal-semiconductor heterostructures involves complex processes and mechanisms, which are still poorly understood. We explore the plasmon-mediated carrier transfer mechanism and the synergistic effect of light and electric fields on Ag-TiO2 heterostructures, through a combination of electrochemical surface-enhanced Raman spectroscopy and photoelectrochemical methods, with para-aminothiophenol (PATP) serving as a probe molecule. The results show that photocurrent responses are dependent on not only excitation wavelengths and applied potentials, but also the irreversibility of redox. The relationship between photocurrent responses and the chemical transformation between PATP and 4,4'-dimercaptoazobenzene is established, reflecting the photo-induced charge transfer of the heterostructures. The collaboration of spectroscopic and photoelectrochemical methods provide valuable insights into the chemical transformation and kinetic information of adsorbed molecules on the heterostructure during PMCR, offering opportunities for modulating of photocatalytic activities of hot carriers.

10.
Anal Chem ; 96(23): 9610-9620, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38822784

RESUMEN

The emerging field of nanoscale infrared (nano-IR) offers label-free molecular contrast, yet its imaging speed is limited by point-by-point traverse acquisition of a three-dimensional (3D) data cube. Here, we develop a spatial-spectral network (SS-Net), a miniaturized deep-learning model, together with compressive sampling to accelerate the nano-IR imaging. The compressive sampling is performed in both the spatial and spectral domains to accelerate the imaging process. The SS-Net is trained to learn the mapping from small nano-IR image patches to the corresponding spectra. With this elaborated mapping strategy, the training can be finished quickly within several minutes using the subsampled data, eliminating the need for a large-labeled dataset of common deep learning methods. We also designed an efficient loss function, which incorporates the image and spectral similarity to enhance the training. We first validate the SS-Net on an open stimulated Raman-scattering dataset; the results exhibit the potential of 10-fold imaging speed improvement with state-of-the-art performance. We then demonstrate the versatility of this approach on atomic force microscopy infrared (AFM-IR) microscopy with 7-fold imaging speed improvement, even on nanoscale Fourier transform infrared (nano-FTIR) microscopy with up to 261.6 folds faster imaging speed. We further showcase the generalization of this method on AFM-force volume-based multiparametric nanoimaging. This method establishes a paradigm for rapid nano-IR imaging, opening new possibilities for cutting-edge research in materials, photonics, and beyond.

11.
Front Oncol ; 14: 1361250, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38841172

RESUMEN

Sarcomatoid renal cell carcinoma (SRCC), a manifestation of sarcomatoid dedifferentiation in renal cell carcinoma, is characterized by elevated invasiveness and a grim prognosis. Typically, SRCC patients present with advanced or metastatic conditions and survival rates rarely extend beyond one year. In this study, we describe a case of SRCC characterized by the patient exhibiting right flank pain without hematuria. Initially, imaging interpretations led to a diagnosis of severe hydronephrosis. Subsequently, an open right nephrectomy post-surgery confirmed the pathology of sarcomatoid renal cell carcinoma.

12.
Molecules ; 29(12)2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38930928

RESUMEN

A mild, efficient and practical protocol for the preparation of 2-sulfonylquinolines through CS2/Et2NH-induced deoxygenative C2-H sulfonylation of quinoline N-oxides with readily available RSO2Cl was developed. The reaction proceeded well under transition-metal-free conditions and exhibited a wide substrate scope and functional group tolerance. The preliminary studies suggested that the nucleophilic sulfonyl sources were generated in situ via the reaction of CS2, Et2NH and sulfonyl chlorides.

13.
Anal Chem ; 96(23): 9399-9407, 2024 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-38804597

RESUMEN

Fast and efficient sample pretreatment is the prerequisite for realizing surface-enhanced Raman spectroscopy (SERS) detection of trace targets in complex matrices, which is still a big issue for the practical application of SERS. Recently, we have proposed a highly performed liquid-liquid extraction (LLE)-back extraction (BE) for weak acids/bases extraction in drinking water and beverage samples. However, the performance efficiency decreased drastically on facing matrices like food and biological blood. Based on the total interaction energies among target, interferent, and extractant molecules, solid-phase extraction (SPE) with a higher selectivity was introduced in advance of LLE-BE, which enabled the sensitive (µg L-1 level) and rapid (within 10 min) SERS detection of both koumine (a weak base) and celastrol (a weak acid) in different food and biological samples. Further, the high SERS sensitivity was determined unmanned by Vis-CAD (a machine learning algorithm), instead of the highly demanded expert recognition. The generality of SPE-LLE-BE for various weak acids/bases (2 < pKa < 12), accompanied by the high efficiency, easy operation, and low cost, offers SERS as a powerful on-site and efficient inspection tool in food safety and forensics.


Asunto(s)
Extracción en Fase Sólida , Espectrometría Raman , Espectrometría Raman/métodos , Extracción Líquido-Líquido , Humanos , Triterpenos Pentacíclicos , Análisis de los Alimentos/métodos , Nanopartículas del Metal/química
14.
J Hazard Mater ; 473: 134633, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38772109

RESUMEN

Ion-adsorbed rare earth minerals are rich in medium and heavy rare earth (RE), which are important strategic resources. In this article, a novel approach for the extraction of RE from ion adsorbed minerals was developed. Through a comprehensive assessment of their extraction and separation performance, the hydrophobic deep eutectic solvents (HDES) with a composition of trioctylphosphine oxide (TOPO): dodecanol (LA): 2-thiophenoyltrifluoroacetone (HTTA) = 1:1:1 was determined as the optimal configuration. Under optimized conditions, only RE were extracted by the HDES, while Al, Ca, Mg were not extracted at all. The HDES based extraction obviated the need for diluent such as kerosene, eliminating the generation of impurity removal residues. The RE in the stripping solution could be successfully enriched by saponified lauric acid, achieving an impressive precipitation rate of 99.7%. The RE precipitate underwent further enrichment, resulting in a RE concentration of 176 g/L (REO = 210 g/L). Unlike industrial precipitants such as oxalic acid and ammonium bicarbonate, lauric acid can be effectively recycled, thereby avoiding a large amount of wastewater and carbon dioxide emissions. The obtained RE solution product exhibits high yield and purity, this study provides an eco-friendly and high-yield approach for extracting RE.

15.
RSC Adv ; 14(20): 14465-14469, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38699687

RESUMEN

A general, efficient and practical protocol for Ts2O promoted deoxygenative dithiocarbamation of quinoline N-oxides with in situ generated dithiocarbamic acids from CS2 and amines is reported. The reaction proceeded well under transition-metal free conditions to obtain a variety of novel quinoline-dithiocarbamate compounds with wide functional group tolerance and good to high yields.

16.
Nat Mater ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589543

RESUMEN

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

17.
J Org Chem ; 89(8): 5560-5572, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38564232

RESUMEN

A simple, efficient, and practical method for the synthesis of S-quinolyl xanthates was developed via Ts2O-promoted deoxygenative C-H dithiocarbonation of quinoline N-oxides with various potassium O-alkyl xanthates. The reaction performed well under transition-metal-free, base-free, and room-temperature conditions with wide substrate tolerance. Employing potassium O-tert-butyl xanthate (tBuOCS2K) as a nucleophile, some valuable quinoline-2-thiones were unexpectedly obtained in a one-pot reaction without any additional base.

18.
Chemphyschem ; 25(15): e202400330, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38676545

RESUMEN

Copper is widely used in everyday life and industrial production because of its good electrical and thermal conductivity. To overcome copper oxidation and maintain its good physical properties, small organic molecules adsorbed on the surface of copper make a passivated layer to further avoid copper corrosion. In this work, we have investigated thioglycolic acid (TGA, another name is mercaptoacetic acid) adsorbed on copper surfaces by using density functional theory (DFT) calculations and a periodical slab model. We first get five stable adsorption structures, and the binding interaction between TGA and Cu(111) surfaces by using density of states (DOS), indicating that the most stable configuration adopts a triple-end binding model. Then, we analyze the vibrational Raman spectra of TGA adsorbed on the Cu(111) surface and make vibrational assignments according to the vibrational vectors. Finally, we explore the temperature effect of the thermodynamically Gibbs free energy of TGA on the Cu(111) surface and the antioxidant ability of the small organic molecular layer of copper oxidation on the copper surface. Our calculated results further provide evidences to interpret the stability of adsorption structures and antioxidant properties of copper.

19.
Hypertens Res ; 47(7): 1881-1891, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38600277

RESUMEN

The evidence regarding the effects of blood pressure changes on older individuals remains inconclusive, and the impact of frailty throughout the life course is not known. We investigated the associations of different change patterns of blood pressure during 3-year intervals with frailty and mortality. Participants included 7335 persons from 2008 to 2014 of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Change in blood pressure was calculated as the difference between follow-up and baseline. Frailty was evaluated using a 40-item frailty index. Mortality status was ascertained up to December 31, 2014. The mean age of participants was 82.6 ± 10.7 years. The optimal blood pressure level (SBP, 130-150 mmHg; DBP, 70-90 mmHg) was associated with the lowest risk of frailty while decreasing follow-up SBP and DBP were significantly correlated with frailty. Lower baseline blood pressure levels (SBP < 130 mmHg; DBP < 70 mmHg) were associated with decreased mortality risk when participants increased their blood pressure to optimal levels during follow-up SBP and DBP (0.78, 0.63-0.98), compared to maintaining a steady low SBP (< 130 mmHg) and DBP (< 70 mmHg). For those with DBP around 70-90 mmHg, decreasing follow-up DBP (< 70 mmHg) was associated with higher mortality (1.23, 1.07-1.42) compared to maintaining stable follow-up DBP (70-90 mmHg). These results remain significant after adjusting for frailty. Optimal blood pressure levels were associated with the lowest risk of frailty. The association between lower blood pressure and increased mortality risk persisted even after accounting for frailty. We used a nationally representative longitudinal cohort study by using 2008-2014 of the Chinese Longitudinal Healthy Longevity in China. Change in blood pressure was calculated as the difference between follow-up and baseline. We investigated the associations of different change patterns of blood pressure during 3-year intervals with frailty and mortality.


Asunto(s)
Presión Sanguínea , Fragilidad , Humanos , Masculino , Femenino , Presión Sanguínea/fisiología , Anciano , China/epidemiología , Fragilidad/mortalidad , Anciano de 80 o más Años , Estudios Longitudinales , Estudios de Cohortes , Hipertensión/mortalidad , Hipertensión/fisiopatología , Factores de Riesgo , Longevidad , Anciano Frágil/estadística & datos numéricos , Mortalidad
20.
Angew Chem Int Ed Engl ; 63(27): e202405379, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38639181

RESUMEN

Due to the superior catalytic activity and efficient utilization of noble metals, nanocatalysts are extensively used in the modern industrial production of chemicals. The surface structures of these materials are significantly influenced by reactive adsorbates, leading to dynamic behavior under experimental conditions. The dynamic nature poses significant challenges in studying the structure-activity relations of catalysts. Herein, we unveil an anomalous entropic effect on catalysis via surface pre-melting of nanoclusters through machine learning accelerated molecular dynamics and free energy calculation. We find that due to the pre-melting of shell atoms, there exists a non-linear variation in the catalytic activity of the nanoclusters with temperature. Consequently, two notable changes in catalyst activity occur at the respective temperatures of melting for the shell and core atoms. We further study the nanoclusters with surface point defects, i.e. vacancy and ad-atom, and observe significant decrease in the surface melting temperatures of the nanoclusters, enabling the reaction to take place under more favorable and milder conditions. These findings not only provide novel insights into dynamic catalysis of nanoclusters but also offer new understanding of the role of point defects in catalytic processes.

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