Publications by authors named "Zengquan Xu"

Various 4-vinyl-1,2-oxaphospholane 2-oxides are prepared in good to excellent yields from vinyloxiranes and in situ-generated phosphenes from phosphoryl diazomethanes via the phosphene-induced ring expansion of oxiranes. The reaction is a novel and expeditious strategy for the synthesis of 1,2-oxaphospholane 2-oxide derivatives, featuring ring expansion of readily available starting materials, high atom economy, no catalyst, a fast reaction rate, broad functional group tolerance, high yields, and separable diastereomers.

View Article and Find Full Text PDF

Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are important polyunsaturated fatty acids (PUFAs) used as nutritional supplements. The natural EPA content in sp. is low, and traditional strategies to increase EPA levels often compromise DHA content or lipid accumulation, hindering industrial coproduction.

View Article and Find Full Text PDF

Analogous to the aqueous solution where the pH of the solvent affects its multiple behaviors, the optical acidity and basicity of molten salts also greatly influence their thermophysical and thermochemical properties. In the study, we develop ion probes to quantitatively determine the acidity-basicity scale of molten NaCl-AlCl ( = 1.5-2.

View Article and Find Full Text PDF

Surface-enhanced Raman spectroscopy (SERS) has evolved significantly over fifty years into a powerful analytical technique. This review aims to achieve five main goals. (1) Providing a comprehensive history of SERS's discovery, its experimental and theoretical foundations, its connections to advances in nanoscience and plasmonics, and highlighting collective contributions of key pioneers.

View Article and Find Full Text PDF

The baroreflex is one of the most important control mechanisms in the human cardiovascular system. This work utilises a closed-loop in silico model of baroreflex regulation, coupled to pulsatile mechanical models with (i) one heart chamber and 36-parameters and (ii) four chambers and 51 parameters. We perform the first global sensitivity analysis of these closed-loop systems which considers both cardiovascular and baroreflex parameters, and compare the models with their respective unregulated equivalents.

View Article and Find Full Text PDF

As a significant new mode of trade export in the digital economy era, cross-border e-commerce injects new momentum into trade cooperation among the Regional Comprehensive Economic Partnership (RCEP) member countries. This paper utilizes multi-dimensional panel data constructed from World Bank databases and UNCTAD databases from 2012 to 2021 to analyze the impact mechanism of RCEP member countries' digital economy development on China's cross-border e-commerce export through direct and indirect channels and conducts empirical tests on it. The research results show that, in terms of direct impact, the development of the digital economy in RCEP member countries has promoted China's cross-border e-commerce export, and its impact is heterogeneous.

View Article and Find Full Text PDF

The tracer gas wind measurement method must measure the average concentration based on the known mixing distance of the tracer gas in order to accurately calculate the air volume. we established a T-shaped cross-ventilation duct with a square cross-sectional side of 0.3 m to simulate mine tunnels experimentally, and created the above duct model in Fluent software.

View Article and Find Full Text PDF

Alfalfa (Medicago sativa) is known to release allelopathic substances to affect the germination and growth of other plants, which have the potential to be applied in controlling weeds. Green foxtail (Setaria viridis) and barnyardgrass (Echinochloa crus-galli), as malignant weeds worldwide, also pose a serious threat to alfalfa in northern China. In this study, the sensitivity of the two weeds to the extracts from the first, second, and third stubbles of six varieties were investigated to further reveal the allelopathic interference of different varieties of alfalfa on notorious weeds.

View Article and Find Full Text PDF

Abstract: We aim to investigate the optimal timing for surgical interventions to maximize patient benefit.

Background: The guidelines recommending a minimum deferral of six months for non-cardiac surgeries following drug-eluting stent percutaneous coronary intervention (DES-PCI) do not adequately address the requirements for individuals undergoing gastrointestinal cancer surgery (GCS).

Methods: The study encompassed 2,501 patients treated from January 2017 to December 2021, all of whom underwent GCS within one year after DES-PCI.

View Article and Find Full Text PDF

Background: Aneurysmal subarachnoid hemorrhage (aSAH) can lead to cognitive impairment, but underlying neural mechanisms remain to be elucidated.

Materials And Methods: To predict long-term cognitive impairment after aSAH, resting electroencephalography (EEG) was measured in 112 patients hospitalized with a diagnosis of aSAH (n = 66) or unruptured intracranial aneurysms (UIA; controls) (n = 46). A neuropsychological battery was administered 8 to 24 months after discharge.

View Article and Find Full Text PDF

Obesity leads to a variety of health risks, and lead, which is ranked second in Agency for Toxic Substances and Disease Registry's priority list of harmful substances, may be more harmful to individuals that are obese. C57BL/6 mice were fed a normal diet or a high-fat diet with or without exposure to 1 g/L lead exposure in drinking water for 8 consecutive weeks. Serum and hepatic biochemistry analysis, histopathological observation, and RT-qPCR were used to explore the potential mechanism of liver damage in obese individuals after Pb exposure, and fecal microbiota transplantation was performed to investigate the role of the gut microbiota in the progression of fatty liver disease.

View Article and Find Full Text PDF

Background: Central nervous system (CNS) cancers are highly lethal and increasingly affect younger populations aged 20-49, posing significant challenges to global healthcare systems. Current research on early-onset CNS cancer trends is limited and outdated, with uncertain impacts from the COVID-19 pandemic. This study explores the epidemiology of early-onset CNS cancer and the pandemic's effects.

View Article and Find Full Text PDF

Proton electrochemistry holds eminent potential for developing high capacity and rate energy storage devices in the post-lithium era. However, the decomposition of water in acidic aqueous electrolytes causes electrode corrosion, leading to capacity fading. Herein, we report a judicious design of molecular micellar aggregates as non-aqueous electrolytes for stable and high-voltage electrochemical proton storage.

View Article and Find Full Text PDF

This study presents a multi-mode X-ray detection and imaging strategy by integrating photochromism, photoluminescence, and radioluminescence into Tb-doped CaAlSiO. CaAlSiO: Tb exhibits stable radioluminescence, oxygen vacancy-related photochromism, and photoluminescence modulation, all of which showed a linear relationship with X-ray exposure. This multi-mode response enables high-quality imaging and detection in both bright and dark conditions, facilitating time-dependent cumulative X-ray radiation dose assessments.

View Article and Find Full Text PDF

In this study, we reported a new approach to activate the C-F bond of trifluoromethylarenes to achieve the hydro-difluoroalkylation of arylethylenes using photoexcited Hantzsch esters (HEs) anions. A wide range of α,α-difluoroalkanes was synthesized. Late-stage functionalization of drug molecules and synthesis of bioactive molecule bioisostere were also presented.

View Article and Find Full Text PDF

Objective: To use pharmacodynamics, molecular biology studies, network pharmacology, and molecular docking to study the mechanism of action of the Ligusticum wallichii (known as Chuanxiong in China, CX) and borneol (known as Bingpian in China, BP) medication pair (CXBP) for the treatment of ischemic stroke.

Methods: The TCMSP, ETCM, and SymMap databases provided the effective chemical components and targets of CXBP, while the databases OMIM, GeneCards, TTD, Pubmed, Web of Science, CNKI, Wanfang Data, and VIP Database provided targets relevant to ischemic stroke. In addition we conducted animal experiments for validation.

View Article and Find Full Text PDF

Drug nanocrystal engineering is an attractive pharmaceutical approach to enhancing the oral bioavailability of poorly soluble drugs. The mechanism of drug nanocrystal stabilization, however, is unclear. Here we developed andrographolide nanocrystals (AG-NCs) with various nonionic surfactants (Pluronic-F127, TPGS, or Brij-S20).

View Article and Find Full Text PDF

With the increasing global focus on sustainable materials, paper is favored for its biodegradability and low cost. Their integration with triboelectric nanogenerators (TENGs) establishes broad prospects for self-powered, paper-based triboelectric materials. However, these materials inherently lack efficient charge storage structures, leading to rapid charge dissipation.

View Article and Find Full Text PDF

Although methods for synthesizing chiral phosphorus scaffolds are available, the potential of this molecular chirality remains largely unexplored. Herein, we present a remote desymmetrization of prochiral biaryl phosphine oxides through an organocatalytic asymmetric arylation. This metal-free approach enables the efficient synthesis of a wide range of densely functionalized P(V)-stereogenic compounds with good to excellent yields and satisfactory enantioselectivities.

View Article and Find Full Text PDF

Electrochemical carbon dioxide reduction reaction (CO2RR) to highly value-added C2+ fuels or chemicals is a promising pathway to address environment issues and energy crisis. In the periodic table, Cu as only the candidate can convert CO2 to C2+ products such as C2H4 and C2H5OH due to the suitable absorption energy to reaction intermediate. Application of Cu is limited for its low activity and poor selectivity.

View Article and Find Full Text PDF

Flexible film in display requires multi-functional integration, such as stretchability, flexibility, abrasion resistance, transparency, and shape memory. In this paper, a reasonable design strategy of flexible polyacrylate (PA) film with high transparency, shape memory, excellent abrasion resistance and foldability is presented. The PA films are prepared by free radical polymerization of vinyl-terminated polyurethane (PU) prepolymer as a cross-linking agent and acrylate monomers in ultraviolet (UV) light.

View Article and Find Full Text PDF

Importance: Commercial prices for hospital care are high and vary widely in the US. Employers and state policymakers are exploring reference-based pricing (RBP) to set their payment rates as multiples of Medicare prices; understanding the range of commercial price variation within a hospital is important for calculating the appropriate price targets that are effectively low to generate savings but also feasible and viable to local hospital markets.

Objective: To examine within-hospital maximum-to-minimum commercial hospital price gaps negotiated by 5 national insurers and estimate plan savings if the minimum prices within each hospital are used as new payment level.

View Article and Find Full Text PDF

Purpose: Renal cell carcinoma (RCC), exhibiting remarkable heterogeneity, can be highly infiltrated by regulatory T cells (Tregs). However, the relationship between Treg and the heterogeneity of RCC remains to be explored.

Methods: We acquired single-cell RNA-seq profiles and 537 bulk RNA-seq profiles of TCGA-KIRC cohort.

View Article and Find Full Text PDF