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1.
J Colloid Interface Sci ; 674: 766-777, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38955008

ABSTRACT

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.

3.
Molecules ; 29(12)2024 Jun 16.
Article in English | MEDLINE | ID: mdl-38930928

ABSTRACT

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.

4.
Anal Chem ; 96(23): 9610-9620, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38822784

ABSTRACT

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.

5.
Front Oncol ; 14: 1361250, 2024.
Article in English | MEDLINE | ID: mdl-38841172

ABSTRACT

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.

6.
Anal Chem ; 96(23): 9399-9407, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38804597

ABSTRACT

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.


Subject(s)
Solid Phase Extraction , Spectrum Analysis, Raman , Spectrum Analysis, Raman/methods , Liquid-Liquid Extraction , Humans , Pentacyclic Triterpenes , Food Analysis/methods , Metal Nanoparticles/chemistry
7.
J Hazard Mater ; 473: 134633, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38772109

ABSTRACT

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.

8.
RSC Adv ; 14(20): 14465-14469, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38699687

ABSTRACT

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.

9.
Angew Chem Int Ed Engl ; 63(27): e202405379, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38639181

ABSTRACT

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.

10.
J Am Chem Soc ; 146(22): 15320-15330, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38683738

ABSTRACT

Palladium hydrides (PdHx) are pivotal in both fundamental research and practical applications across a wide spectrum. PdHx nanocrystals, synthesized by heating in dimethylformamide (DMF), exhibit remarkable stability, granting them widespread applications in the field of electrocatalysis. However, this stability appears inconsistent with their metastable nature. The substantial challenges in characterizing nanoscale structures contribute to the limited understanding of this anomalous phenomenon. Here, through a series of well-conceived experimental designs and advanced characterization techniques, including aberration-corrected scanning transmission electron microscopy (AC-STEM), in situ X-ray diffraction (XRD), and time-of-flight secondary ion mass spectrometry (TOF-SIMS), we have uncovered evidence that indicates the presence of C and N within the lattice of Pd (PdCxNy), rather than H (PdHx). By combining theoretical calculations, we have thoroughly studied the potential configurations and thermodynamic stability of PdCxNy, demonstrating a 2.5:1 ratio of C to N infiltration into the Pd lattice. Furthermore, we successfully modulated the electronic structure of Pd nanocrystals through C and N doping, enhancing their catalytic activity in methanol oxidation reactions. This breakthrough provides a new perspective on the structure and composition of Pd-based nanocrystals infused with light elements, paving the way for the development of advanced catalytic materials in the future.

11.
Chemphyschem ; : e202400330, 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38676545

ABSTRACT

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.

12.
Hypertens Res ; 47(7): 1881-1891, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38600277

ABSTRACT

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.


Subject(s)
Blood Pressure , Frailty , Humans , Male , Female , Blood Pressure/physiology , Aged , China/epidemiology , Frailty/mortality , Aged, 80 and over , Longitudinal Studies , Cohort Studies , Hypertension/mortality , Hypertension/physiopathology , Risk Factors , Longevity , Frail Elderly/statistics & numerical data , Mortality
13.
J Org Chem ; 89(8): 5560-5572, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38564232

ABSTRACT

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.

14.
Nat Mater ; 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38589543

ABSTRACT

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.

15.
Org Biomol Chem ; 22(18): 3740-3745, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38651658

ABSTRACT

An efficient and practical method for the synthesis of 3-alkenylquinoxalinones containing the SCF3 group has been readily developed through a three-component radical cascade reaction involving quinoxalinones, alkynes and AgSCF3. The reaction was found to be compatible with a variety of substrates and exhibited a high functional group tolerance and complete E-selectivity. The preliminary study suggests the involvement of a SCF3 radical in the transformation.

16.
Anal Chem ; 96(17): 6550-6557, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38642045

ABSTRACT

There is growing interest in developing a high-performance self-supervised denoising algorithm for real-time chemical hyperspectral imaging. With a good understanding of the working function of the zero-shot Noise2Noise-based denoising algorithm, we developed a self-supervised Signal2Signal (S2S) algorithm for real-time denoising with a single chemical hyperspectral image. Owing to the accurate distinction and capture of the weak signal from the random fluctuating noise, S2S displays excellent denoising performance, even for the hyperspectral image with a spectral signal-to-noise ratio (SNR) as low as 1.12. Under this condition, both the image clarity and the spatial resolution could be significantly improved and present an almost identical pattern with a spectral SNR of 7.87. The feasibility of real-time denoising during imaging was well demonstrated, and S2S was applied to monitor the photoinduced exfoliation of transition metal dichalcogenide, which is hard to accomplish by confocal Raman spectroscopy. In general, the real-time denoising capability of S2S offers an easy way toward in situ/in vivo/operando research with much improved spatial and temporal resolution. S2S is open-source at https://github.com/3331822w/Signal2signal and will be accessible online at https://ramancloud.xmu.edu.cn/tutorial.

17.
Proc Natl Acad Sci U S A ; 121(14): e2305297121, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38551842

ABSTRACT

The causal connectivity of a network is often inferred to understand network function. It is arguably acknowledged that the inferred causal connectivity relies on the causality measure one applies, and it may differ from the network's underlying structural connectivity. However, the interpretation of causal connectivity remains to be fully clarified, in particular, how causal connectivity depends on causality measures and how causal connectivity relates to structural connectivity. Here, we focus on nonlinear networks with pulse signals as measured output, e.g., neural networks with spike output, and address the above issues based on four commonly utilized causality measures, i.e., time-delayed correlation coefficient, time-delayed mutual information, Granger causality, and transfer entropy. We theoretically show how these causality measures are related to one another when applied to pulse signals. Taking a simulated Hodgkin-Huxley network and a real mouse brain network as two illustrative examples, we further verify the quantitative relations among the four causality measures and demonstrate that the causal connectivity inferred by any of the four well coincides with the underlying network structural connectivity, therefore illustrating a direct link between the causal and structural connectivity. We stress that the structural connectivity of pulse-output networks can be reconstructed pairwise without conditioning on the global information of all other nodes in a network, thus circumventing the curse of dimensionality. Our framework provides a practical and effective approach for pulse-output network reconstruction.

18.
Angew Chem Int Ed Engl ; 63(20): e202403114, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38488787

ABSTRACT

The conversion of methane under ambient conditions has attracted significant attention. Although advancements have been made using active oxygen species from photo- and electro- chemical processes, challenges such as complex catalyst design, costly oxidants, and unwanted byproducts remain. This study exploits the concept of contact-electro-catalysis, initiating chemical reactions through charge exchange at a solid-liquid interface, to report a novel process for directly converting methane under ambient conditions. Utilizing the electrification of commercially available Fluorinated Ethylene Propylene (FEP) with water under ultrasound, we demonstrate how this interaction promote the activation of methane and oxygen molecules. Our results show that the yield of HCHO and CH3OH can reach 467.5 and 151.2 µmol ⋅ gcat -1, respectively. We utilized electron paramagnetic resonance (EPR) to confirm the evolution of hydroxyl radicals (⋅OH) and superoxide radicals (⋅OOH). Isotope mass spectrometry (MS) was employed to analyze the elemental origin of CH3OH, which can be further oxidized to HCHO. Additionally, we conducted density functional theory (DFT) simulations to assess the reaction energies of FEP with H2O, O2, and CH4 under these conditions. The implications of this methodology, with its potential applicability to a wider array of gas-phase catalytic reactions, underscore a significant advance in catalysis.

19.
Org Biomol Chem ; 22(12): 2409-2413, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38411219

ABSTRACT

A convenient, efficient and practical approach for the synthesis of S-quinolyl phosphorothioates via cheap TsCl promoted deoxygenative C2-H phosphorothiolation of quinoline N-oxides with readily available triethylammonium O,O-dialkylphosphorothioates was developed. The reaction performed well under transition-metal-free conditions at room temperature with a very short reaction time (10-20 min). Preliminary studies showed that the current transformation underwent a nucleophilic substitution process.

20.
J Affect Disord ; 351: 641-648, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38309482

ABSTRACT

BACKGROUND: Growing evidence suggests that meal timing may influence dietary choices and mental health. Thus, this study examined the association between macronutrient consumption quality, food source, meal timing, and depression prevalence in Americans. METHODS: 23,313 National Health and Nutrition Survey participants from 2007 to 2016 were included in this cross-sectional study. Macronutrient intake was calculated for all day, dinner, and breakfast and subtypes into 4 classes. Based on the Patient Health Questionnaire, depression was defined as a 9-item score ≥ 10 on the PHQ-9. The correlation between macronutrients and depression prevalence was estimated with multivariable logistic regression models and isocaloric substitution effects. RESULTS: Low-quality carbohydrates (OR = 1.54, 95 % CI: 1.11, 2.12) were positively linked to depression compared with the lowest quartile, after adjusting for age and other covariates. In contrast, total high-quality carbohydrate (OR = 0.52, 95 % CI: 0.40, 0.66), total animal protein (OR = 0.60, 95 % CI: 0.45, 0.80), and total vegetable protein (OR = 0.61, 95 % CI: 0.43, 0.85) were negatively associated with depression was negatively associated. Replacing low-quality carbohydrates with high-quality carbohydrates throughout the day reduced the risk of depression by approximately 15 %. LIMITATIONS: Cross-sectional data. CONCLUSION: All in all, diet plays a crucial role in the prevention and treatment of depression. Especially in terms of macronutrient intake, high-quality, moderate intake can reduce the risk of depression. However, different subtypes of macronutrient consumption may have different effects on depression, so it becomes crucial to carefully consider the selection and combination of macronutrients.


Subject(s)
Depression , Energy Intake , Adult , Humans , Cross-Sectional Studies , Depression/epidemiology , Dietary Fats , Dietary Proteins , Nutrients , Diet , Dietary Carbohydrates , Food Quality
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