Characterization and Mechanism Elucidation of Nano-TiO2 Composites Prepared by Gaseous Detonation Method.

In this study, a series of nano-TiO2 composite materials, including nano-TiO2, nano-SnO2/TiO2, nano-SiO2/TiO2, and nano-Fe2O3/TiO2, were successfully synthesized via the gaseous detonation method. Comprehensive characterization of the synthesized samples was carried out through X-ray diffraction (XRD), transmission electron microscopy/high-resolution TEM (TEM/HRTEM), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), Brunauer-Emmett-Teller (BET) method, and Fourier transform infrared (FTIR) analysis, which unveiled the significant influence of precursor types on the microstructure of the composite materials. Specifically, the incorporation of Sn4+ promoted the transformation of TiO2 to the rutile phase, reducing particle sizes from 25 to 19 nm and increasing the specific surface area from 44 to 86 m2/g. In contrast, the introduction of SiO2 impeded the rutile phase formation, leading to a marked reduction in particle size to 14 nm and an enhancement of the specific surface area to 104 m2/g. Furthermore, the presence of Fe3+ promoted the formation of the rutile phase and enabled particle growth to 44 nm. These findings not only deepen the understanding of structural control in the synthesis of nano-TiO2 composite materials via the gaseous detonation method but also highlight the critical role of precursor selection in determining the properties of the resulting materials.

Risk analysis of air pollutants and types of anemia: a UK Biobank prospective cohort study.

Previous studies have suggested that exposure to air pollutants may be associated with specific blood indicators or anemia in certain populations. However, there is insufficient epidemiological data and prospective evidence to evaluate the relationship between environmental air pollution and specific types of anemia. We conducted a large-scale prospective cohort study based on the UK Biobank. Annual average concentrations of NO2, PM2.5, PM2.5-10, and PM10 were obtained from the ESCAPE study using the Land Use Regression (LUR) model. The association between atmospheric pollutants and different types of anemia was investigated using the Cox proportional hazards model. Furthermore, restricted cubic splines were used to explore exposure-response relationships for positive associations, followed by stratification and effect modification analyses by gender and age. After adjusting for demographic characteristics, 3-4 of the four types of air pollution were significantly associated with an increased risk of iron deficiency, vitamin B12 deficiency and folate deficiency anemia, while there was no significant association with other defined types of anemia. After full adjustment, we estimated that the hazard ratios (HRs) of iron deficiency anemia associated with each 10 µg/m3 increase in NO2, PM2.5, and PM10 were 1.04 (95%CI: 1.02, 1.07), 2.00 (95%CI: 1.71, 2.33), and 1.10 (95%CI: 1.02, 1.20) respectively. The HRs of folate deficiency anemia with each 10 µg/m3 increase in NO2, PM2.5, PM2.5-10, and PM10 were 1.25 (95%CI: 1.12, 1.40), 4.61 (95%CI: 2.03, 10.47), 2.81 (95%CI: 1.11, 7.08), and 1.99 (95%CI: 1.25, 3.15) respectively. For vitamin B12 deficiency anemia, no significant association with atmospheric pollution was found. Additionally, we estimated almost linear exposure-response curves between air pollution and anemia, and interaction analyses suggested that gender and age did not modify the association between air pollution and anemia. Our research provided reliable evidence for the association between long-term exposure to PM10, PM2.5, PM2.5-10, NO2, and several types of anemia. NO2, PM2.5, and PM10 significantly increased the risk of iron deficiency anemia and folate deficiency anemia. Additionally, we found that the smaller the PM diameter, the higher the risk, and folate deficiency anemia was more susceptible to air pollution than iron deficiency anemia. No association was observed between the four types of air pollution and hemolytic anemia, aplastic anemia, and other types of anemia. Although the mechanisms are not well understood, we emphasize the need to limit the levels of PM and NO2 in the environment to reduce the potential impact of air pollution on folate and iron deficiency anemia.

Association between pro-inflammatory diet and abdominal pain: cross-sectional and case-control study from UK biobank and NHANES 2017-2020.

BACKGROUND: There is a close association between diet and abdominal pain; however, relationship between inflammatory diet and characteristics of abdominal pain has not been characterized yet. METHODS: This study analyzed baseline data from the UK Biobank, 3-item DHQ-Abdominal Pain Questionnaire (DHQ-3Q), which including abdominal pain in the past 3 months, severity of abdominal pain, and frequency of abdominal pain, and data from the National Health and Nutrition Examination Survey (NHANES) from 2017 to 2020. Energy-adjusted Dietary Inflammatory Index (E-DII), constructed based on 26 or 27 nutrients, was analyzed using continuous or categorical methods. Logistic regression and restricted cubic spline analyses examined the association between E-DII and abdominal pain. RESULTS: In UK Biobank, compared to participants in the lowest quintile of E-DII, the adjusted ORs for the highest quintile were 1.12 (95% CI 1.02-1.24; P = .022), 1.05 (95% CI 1.00-1.09; P = .030), 1.26 (95% CI 1.17-1.36; P < .001), and 1.10 (95% CI 1.00-1.20; P = .044) for chronic abdominal pain, abdominal pain in the past three months, severity of abdominal pain, and frequency of abdominal pain, respectively. In NHANES, compared to participants in the lowest quintile of E-DII, the adjusted ORs for the highest quintile were 1.46 (95% CI 1.20-1.77;P < .001), 1.75 (95% CI 1.20-2.60; P = .005), 1.45 (95% CI 1.14-1.87; P = .003), and 1.18 (95% CI 0.82-1.72; P = .380) for abdominal pain in the past year, upper left abdominal pain, upper middle abdominal pain, and upper right abdominal pain. Additionally, there was a nonlinear correlation between E-DII score and DHQ-3Q (P nonlinear <.001). CONCLUSION: Following a pro-inflammatory diet is linked to a higher likelihood of experiencing abdominal pain, as well as increased severity and frequency of such pain. Therefore, further longitudinal studies are necessary to investigate this relationship.

An experimental instrument for solidification and in situ characterization of the nucleation behavior of high-melting metal under a high magnetic field.

A specially designed experimental apparatus suitable for commercial superconductor magnet is used for solidification and in situ characterization of the nucleation behavior of high-melting metals. In order to carry out solidification experiments under a high magnetic field (HMF), the sample cell in the experimental device has two stations for repeated verification experiments of two same samples or comparative experiments of two different samples. Meanwhile, a metal specimen and a reference (α-Al2O3) are placed in the sample cell to characterize the nucleation behavior in situ. Using this experimental device, the nucleation behaviors of Al-7wt. %Si alloy and pure Cu under a HMF were investigated. The results show that the undercoolings of Al-7wt. %Si alloy and pure Cu increase under the HMF. Furthermore, the applied HMF decreases the activation energy of Al-7wt. %Si alloy and increases the nucleation work. Based on the magnetohydrodynamic effect, the change in undercooling and nucleation work could be partly attributed to the restrained thermal convection by the HMF in this study.

Design, synthesis and biological evaluation of chalcone derivatives as potent and orally active hCYP3A4 inhibitors.

Human cytochrome P450 3A4 (hCYP3A4), one of the most important drug-metabolizing enzymes, catalyze the metabolic clearance of ∼50% therapeutic drugs. CYP3A4 inhibitors have been used for improving the in vivo efficacy of hCYP3A4-substrate drugs. However, most of existing hCYP3A4 inhibitors may trigger serious adverse effects or undesirable effects on endogenous metabolism. This study aimed to discover potent and orally active hCYP3A4 inhibitors from chalcone derivatives and to test their anti-hCYP3A4 effects both in vitro and in vivo. Following three rounds of screening and structural optimization, the isoquinoline chalcones were found with excellently anti-hCYP3A4 effects. SAR studies showed that introducing an isoquinoline ring on the A-ring significantly enhanced anti-CYP3A4 effect, generating A10 (IC50 = 102.10 nM) as a promising lead compound. The 2nd round of SAR studies showed that introducing a substituent group at the para position of the carbonyl group on B-ring strongly improved the anti-CYP3A4 effect. As a result, C6 was identified as the most potent hCYP3A4 inhibitor (IC50 = 43.93 nM) in human liver microsomes (HLMs). C6 also displayed potent anti-hCYP3A4 effect in living cells (IC50 = 153.00 nM), which was superior to the positive inhibitor ketoconazole (IC50 = 251.00 nM). Mechanistic studies revealed that C6 could potently inhibit CYP3A4-catalyzed N-ethyl-1,8-naphthalimide (NEN) hydroxylation in a competitive manner (Ki = 30.00 nM). Moreover, C6 exhibited suitable metabolic stability in HLMs and showed good safety profiles in mice. In vivo tests demonstrated that C6 (100 mg/kg, orally administration) significantly increased the AUC(0-inf) of midazolam by 3.63-fold, and strongly prolonged its half-life by 1.66-fold compared with the vehicle group in mice. Collectively, our findings revealed the SARs of chalcone derivatives as hCYP3A4 inhibitors and offered several potent chalcone-type hCYP3A4 inhibitors, while C6 could serve as a good lead compound for developing novel, orally active CYP3A4 inhibitors with improved druglikeness properties.

Construction of TiO2-x Confined by Layered Iron Silicate toward Efficient Visible-Light-Driven Photocatalysis-Fenton Synergistic Removal of Organic Pollutants.

The photocatalysis-Fenton synergistic reaction has great potential for water purification but generally suffers from unsatisfactory electron transfer due to an undesirable interface structure. Herein, we developed a novel heterojunction of oxygen vacancy-rich TiO2-x confined in the layer space of a synthetic montmorillonite-like iron silicate (denoted as TiO2-x/FeMMT) that addresses the issue mentioned above. Two-dimensional layered montmorillonite-like silicates in heterojunctions as a support not only provided more active sites for the reaction but also induced oxygen vacancies in TiO2-x through interfacial effects to enhance the visible-light harvesting ability. Notably, such loading TiO2-x as an electron donor accelerated the Fe(III)/Fe(II) redox cycling and facilitated the effective activation of H2O2, while Fe(III) in the montmorillonite-like silicate as electron trap sites greatly improved the separation of photogenerated electron-hole pairs. More interestingly, the internal electric field and oxygen vacancies (Vo) existing at the interface realized the directional migration of photogenerated electrons and improved the energy band structure of the heterojunction, respectively. Eventually, the TiO2-x/FeMMT composites exhibited superior photocatalysis-Fenton performance toward degradation removal of phenol, dinotefuran (DIN), and sulfamethoxazole (SMX) under visible-light irradiation. This paves the way for the rational design of high-efficiency heterojunction catalysts based on layered silicates for environment-related applications.

1,2-Difunctionalization of Acetylene Enabled by Light.

Although the direct conversion of gaseous acetylene into value-added liquid commodity chemicals is becoming increasingly attractive, the majority of the established methodologies are focused on cross-coupling, hydro-functionalization, and polymerization. Herein, we describe a 1,2-difunctionalization method that inserts acetylene directly into readily available bifunctional reagents. This method provides access to diverse C2-linked 1,2-bis-heteroatom products in high regio- and stereoselectivity along with opening up previously unexplored synthetic directions. In addition, we demonstrate this method's synthetic potential by converting the obtained products into diverse functionalized molecules and chiral sulfoxide-containing bidentate ligands. Using a combination of experimental and theoretical methods, the mechanism for this insertion reaction was investigated.

Thiol-Yne click chemistry of acetylene-enabled macrocyclization.

Macrocycles have fascinated scientists for over half a century due to their aesthetically appealing structures and broad utilities in chemical, material, and biological research. However, the efficient preparation of macrocycles remains an ongoing research challenge in organic synthesis because of the high entropic penalty involved in the ring-closing process. Herein we report a photocatalyzed thiol-yne click reaction to forge diverse sulfur-containing macrocycles (up to 35-membered ring) and linear C2-linked 1,2-(S-S/S-P/S-N) functionalized molecules, starting from the simplest alkyne, acetylene. Preliminary mechanistic experiments support a visible light-mediated radical-polar crossover dihydrothiolation process. This operationally straightforward reaction is also amenable to the synthesis of organometallic complexes, bis-sulfoxide ligand and a pleuromutilin antibiotic drug Tiamulin, which provides a practical route to synthesize highly valued compounds from the feedstock acetylene gas.

Study on Photocatalytic Performance of Ag/TiO2 Modified Cement Mortar.

In this paper, Ag-TiO2 photocatalysts with different Ag contents (1 mol%-5 mol%) were prepared and applied to cement mortar. The photocatalytic performance of Ag-TiO2 and photocatalytic cement mortar under UV light and simulated solar light was evaluated. The results showed that Ag loading on the surface of TiO2 could reduce its band gap width and increase its absorbance in the visible region, and 2% Ag-TiO2 had the highest photocatalytic activity under UV light, the degradation rate of methyl orange (MO) was 95.5% at 30 min, and the first-order reaction constant k was 0.0980 min-1, which was 61.7% higher than that of TiO2, and 5% Ag-TiO2 had the highest photocatalytic activity under solar light, the degradation rate of methylene blue (MB) was 69.8% at 40 min, and the first-order reaction constant k was 0.0294 min-1, which was 90.9% higher than that of TiO2. The photocatalytic mortar prepared by the spraying method has high photocatalytic performance, The MO degradation rate of sample S2 under UV light was 87.5% after 120 min, MB degradation rate of sample S5 under solar light was 75.4% after 120 min. The photocatalytic reaction conforms to the zero-order reaction kinetics, which was 1.5 times-3.3 times higher than that of the mixed samples and has no effect on the mechanical properties of mortar.

Solid phase "on-situ" quadraplex isotope dimethyl labeling for the analysis of biogenic amines in beers by liquid chromatography-high resolution mass spectrometry.

A simple magnetization method was developed for the preparation of magnetic materials from conventional solid phase packing though coprecipitation and solvothermal approaches. And the prepared magnetic materials were used for magnetic solid phase extraction (MSPE) of biogenic amines (BAs) from beers. Furthermore, to improve the analytical throughput, a solid phase "on-situ" quadraplex isotope dimethyl labeling method was developed for the quantification of BAs by liquid chromatography-high resolution mass spectrometry (LCHRMS). Compared to conventional in-solution labeling, the "on-situ" labeling could simplify the sample preparation procedure and efficiently remove the residuals such as inorganic salts and excessive labeling reagents. The quadraplex labeling, which enabled three real samples and one internal standard sample to be analyzed simultaneously in a single LCHRMS run. For the tested 8 BAs (cadaverine, phenethylamine, spermine, spermidine, tyramine, histamine, putrescine and tryptamine), LODs of 0.02-0.05 µg/L and LOQs of 0.05-0.1 µg/L were achieved at good reproducibility (RSD of 0.5-4.6% and 2.2-7.0% for intra- and inter-day reproducibility, respectively). With this method, six beer samples were analyzed, and these 8 BAs were all detected in the range of low µg/L to 2.9 mg/L, which were lower than maximal residual level (MRL) required in the regulations of China and EU.

Impacts of Built Environment on Urban Vitality: Regression Analyses of Beijing and Chengdu, China.

The loss of urban vitality is an important problem in the development of urban central areas. Analyzing the correlation between urban built environment and urban vitality supports urban planning and design. However, current research excludes the study of how consistent built environment factors affect urban vitality of cities with different development situations. Therefore, using social media check-in data, this paper measures neighborhood vibrancy in urban central areas in Beijing and Chengdu, China. Four levels of spatial information were used to measure the built environment: regulatory planning management unit (RPMU), land use, road network, and building. Regression model is used to quantify the correlation between urban vitality and the built environment of these two cities. The study found a strong correlation between built environment factors and urban vitality. Among the built environment factors, points of interest (POI) diversity and public transport accessibility indicators were strongly positively correlated with neighborhood vibrancy. However, the density indicators had totally different effects on urban vitality of cities with different development situations, which is excluded in existing studies. This research strengthens the practical understanding of the compact city concept, and can support the design and planning of urban built environment.

Functionalization of amino terminated carbon nanotubes with isocyanates for magnetic solid phase extraction of sulfonamides from milk and their subsequent determination by liquid chromatography-high resolution mass spectrometry.

A simple modification method was developed for the functionalization of amino terminated carbon nanotubes (CNT-NH2) by using isocyanates as modifiers via the nucleophilic addition reaction. Two types of functionalized magnetic carbon nanotubes (MCNT) were prepared through deposition of magnetic nanoparticles on CNT-NH2 and modification with different isocyanates. p-Tolyl-functionalized MCNT (Tol-MCNT) with better adsorption performance were selected as adsorbent for magnetic solid phase extraction (MSPE), which could extract sulfonamides (SAs) from various milk samples with a enrichment factor of about 30 after optimization. By combining the MSPE with liquid chromatography-high resolution mass spectrometry (LC-HRMS), a new method was developed. Both skimmed and whole milk samples of three brands were analyzed with this method, and 4 SAs including sulfadiazine, sulfisomidine, sulfamethazine and sulfameter were detected with the concentration from unquantifiable to 72 ng/L, which were all well below the maximum residue limits in milk according to the regulations of China and EU.

A dual removable activating group enabled the Povarov reaction of N-arylalanine esters: synthesis of quinoline-4-carboxylate esters.

A dual removable activating group enabled Povarov reaction of N-arylalanine esters was reported. N-Arylalanine ester was utilized as the sole carbon source to generate N-arylimine and its tautomer, enamine, in situ by aerobic oxidation of sp3 C-H bonds, and then the consecutive reaction delivered the desired quinoline-4-carboxylate esters in high yields.

Acid-degradable cationic methacrylamide polymerized in the presence of plasmid DNA as tunable non-viral gene carrier.

New acid-degradable cationic nanoparticles were synthesized using a monomer-to-polymer approach, which enabled highly flexible nanoparticle fabrication to obtain controlled properties such as size and conjugation with additional functionalities. The nanoparticles were designed to cause swelling and osmotic destabilization of the endosome, while cationic branches holding anionic DNA are cleaved from the polymeric backbone of the nanoparticles and make plasmid DNA accessible for efficient gene expression. Efficient release of plasmid DNA upon hydrolysis of the nanoparticles at the endosomal pH 5.0 and transportation of the released DNA to the nucleus of a cell were shown. In vitro studies showed significantly higher transfection efficiency by the degradable nanoparticles than polyethylenimine (PEI) polyplexes at very low concentrations (i.e., ng/mL). Size-dependent selective transfection of phagocytic cells (e.g., RAW 309 macrophages) and non-phagocytic cells (e.g., NIH 3T3 fibroblasts) was also achieved by using nanoparticles of two different sizes (240 nm and 680 nm in diameter), which implies feasibility of tunable gene therapy and DNA vaccination using the nanoparticle system. Preliminary pulmonary transfection of mice using the degradable nanoparticles demonstrated a remarkably higher expression of firefly luciferase at 70% lower concentration than using naked DNA alone. Implications and further improvement of the nanoparticles to be used in gene therapy are also discussed.

[Anti-atherosclerotic effect of betaine in apolipoprotein E-deficient mice].

OBJECTIVE: To study the effect of betaine on the formation of atherosclerotic plaque in apolipoprotein E (ApoE)-deficient mice and explore its anti-inflammatory mechanism. METHODS: Seven-week-old ApoE-deficient mice (C57BL/6J background) were divided into four groups randomly based on body weight: model group and three betaine groups. Wild-type mice with the same age and genetic background were used as control group. The control group and model group were fed AIN-93G diet. Three betaine groups were fed AIN-93G diet supplemented with 1, 2, 4 g betaine/100 g diet, respectively. Serum tumor necrosis factor-alpha (TNF-alpha), monocyte chemoattractant protein-1, lipid levels and methylation status of TNF-alpha promotor in aorta were determined at 0, 7 and 14 weeks. The percentage of aorta sinus plaque to lumen area was measured at 14-week. RESULTS: The percentage of aorta sinus plaque to lumen area of 1% and 2% betaine groups were (11.43+/-2.65)% and (12.09+/-3.07)%, respectively, which were 41% and 33% smaller than that of the model group (t=3.117, 3.010, respectively, and P<0.01). Serum TNF-alpha level of three betaine groups were (56.33+/-3.86), (63.04+/-4.67) and (65.52+/-3.97) pg/ml, respectively, which were lower than that of the model group (79.40+/-4.68) pg/ml (t=9.270, 6.571 and 5.576, respectively, P<0.001), but there was no significant difference in the methylation status of TNF-alpha promotor among all five groups. CONCLUSION: Betaine could inhibit the development of atherosclerosis via anti-inflammation.

Readily available sulfamide-amine alcohols for enantioselective phenylacetylene addition to aldehydes in the absence of Ti(O(i)Pr)4.

Ephedrine-derived sulfamide-amine alcohol 3 was found to be an effective catalyst for the asymmetric phenylacetylene addition to aldehydes at room temperature without using Ti(O(i)Pr)4 and Zn(OTf)2. It afforded the propargylic alcohols in high yields (up to 99%) and good enantioselectivities (up to 84% ee), which were much higher than that based on N-methylephedrine under the same reaction conditions. Its weakly coordinative sulfonamide moiety of the ligand plays an important role for further acceleration and stereocontrol in the alkynylation.

Concise synthesis of novel practical sulfamide-amine alcohols for the enantioselective addition of diethylzinc to aldehydes.

Novel sulfamide-amine alcohol ligands were designed using a grafting strategy and synthesized from readily available starting materials via a simple, efficient method. The key features of these ligands for the asymmetric addition of diethylzinc to aldehydes included stability, enhanced effectiveness without using Ti(O(i)Pr)(4), suitability for a variety of aldehydes, the ability to operate at room temperature, and selectability to afford either absolute configuration products with enantiomeric excess up to >99%.

Efficient reductive selenation of aromatic aldehydes to symmetrical diselenides with Se/CO/H(2)O under atmospheric pressure.

An efficient method for the synthesis of symmetrical diselenides is described. Reductive selenation of aromatic and heterocyclic aromatic aldehydes (ArCHO) with Se/CO/H(2)O in DMF afforded diselenides (ArCH(2)SeSeCH(2)Ar) in yields up to 94% under atmospheric pressure without use of a base.

Stability and demulsification of emulsions stabilized by asphaltenes or resins.

Experimental data are presented to show the influence of asphaltenes and resins on the stability and demulsification of emulsions. It was found that emulsion stability was related to the concentrations of the asphaltene and resin in the crude oil, and the state of dispersion of the asphaltenes and resins (molecular vs colloidal) was critical to the strength or rigidity of interfacial films and hence to the stability of the emulsions. Based on this research, a possible emulsion minimization approach in refineries, which can be implemented utilizing microwave radiation, is also suggested. Comparing with conventional heating, microwave radiation can enhance the demulsification rate by an order of magnitude. The demulsification efficiency reaches 100% in a very short time under microwave radiation.