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The proton exchange membrane electrolysis cell (PEMEC) has attracted considerable attention for large-scale and efficient hydrogen production because of its high current density, high hydrogen purity and fast dynamic response. Flow field distributions and water and thermal management characteristics of a PEMEC are vital for electrolytic cell structure and the determination of operating condition. A three-dimensional, non-isothermal, electrochemical model of a PEMEC was established in this manuscript. The flow field distribution and water and thermal management of the PEMEC are discussed. The corresponding results showed that the pressure of the flow channel decreased diagonally from the inlet to the outlet, and the pressure and velocity distribution exhibited a downward opening shape of a parabola. At the same inlet flow rate, when the voltage was 1.6 V, the oxygen generation rate was 15.74 mol/(cm2·s), and when the voltage was 2.2 V, the oxygen generation rate was 332.05 mol/(cm2·s); due to the change in the oxygen production rate, the pressure difference at 2.2 V was 2.5 times than that at 1.6 V. When the stoichiometric number was less than two, the average temperature of the catalyst layer (CL) decreased rapidly with the increase in the water flow rate. When the voltage decreased to 2.1 V, the current density came to the highest value when the stoichiometric number was 0.7, then the current density decreased with an increase in the stoichiometric number. When stoichiometric numbers were higher than five, the surface temperature and current density remained basically stable with the increase in the water flow rate, and the water and thermal management and electrolysis characteristics performed better. The research results could optimize the water supply of electrolysis cells. According to the velocity distribution law of the flow field, the water and thermal management performance of the PEMEC could be estimated, further promoting safety and reliability. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) remains a major threat to human health due to the limited energy supply, disordered cell metabolism, massive cardiomyocyte death, and restricted regeneration. Although currently available therapies may relieve myocardial damage, restoring the dysregulated energy metabolism to normal levels has not yet been achieved. MOTS‐c has recently been identified as a regulator of biological metabolism to combat aging; however, its role in reprogramming cardiac metabolism remains to be elucidated. Here, MOTS‐c is chemically conjugated to self‐assembling Q11 peptide to fabricate an injectable hydrogel (MQgel) aimed to improve mitochondria function and cardiomyocyte metabolism post‐MI. It is observed that MQgel effectively protects mitochondria from oxidative damage and normalized cardiomyocyte metabolism, including glucose uptake, glycolysis, and the tricarboxylic acid (TCA) cycle, thereby inhibiting cardiomyocyte death and enhancing cardiomyocyte activity. In a rat MI model, intramyocardial injection of MQgel successfully minimizes the infarct area and fibrosis, promotes angiogenesis, suppresses myocardial hypertrophy, and improves cardiomyocyte survival and metabolic enzyme activity, all of which collaboratively attenuate the maladaptive cardiac remodeling and boost cardiac function and tissue repair. The findings suggest that the self‐assembled mitochondria metabolism‐regulatory peptide hydrogel effectively treats MI, and cellular bioenergy modulation provides a new therapeutic approach for tissue repair after injury. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) are experiencing explosive developments due to their advantages in energy conservation and environmental protection. As a pivotal component of EVs, the safety performance of lithium-ion batteries directly affects driving miles and even safety; hence, a battery thermal management system (BTMS) is especially important. To improve the thermal safety performance of power battery modules, first, a new leak-proof phase change material (PCM)-coupled liquid-cooled composite BTMS for large-scale battery modules is proposed in this research. Second, the numerical simulation analysis method was utilized to analyze the influences of the fluid flow channel shape, working fluid inlet temperature, inlet velocity, and reverse flow conditions on the BTMS. Eventually, the abovementioned performances were compared with the traditional PCM-coupled liquid-cooling strategy. The relative data indicated that the Tmax was reduced by 17.5% and the ΔTmax was decreased by 19.5% compared to the liquid-cooling approach. Further, compared with conventionally designed PCM composite liquid cooling, the ΔTmax was reduced by 34.9%. The corresponding data showed that, when using the e-type flow channel, reverse flow II, the inlet flow velocity was 0.001–0.005 m/s, and the inlet temperature was the ambient temperature of the working condition. The thermal performance of the anti-leakage system with a thermal conduction slot PCM-coupled liquid-cooling composite BTMS reached optimal thermal performance. The outcome proved the superiority of the proposed BTMS regarding temperature control and temperature equalization capabilities. It also further reduced the demand for liquid-cooling components, avoided the problem of the easy leakage of the PCM, and decreased energy consumption. [ABSTRACT FROM AUTHOR]

Liver cancer and healthy individual serum samples were compared based on their spectral features acquired by Raman and fluorescence spectroscopy to initially establish spectral features that can be considered spectral markers for liver cancer diagnosis. Intensity differences of the characteristic peaks of carotenes, proteins, and lipids in the Raman spectra were clearly observed in liver cancer patient serum samples compared to those of normal human serum samples. The changes in the serum fluorescence profiles of liver cancer patients were also analyzed. To probe the capacity and contrast of Raman spectroscopy as an analytical implement for the early diagnosis of liver cancer, principal component analysis was used to analyze the Raman spectra of liver cancer patients and healthy individuals. Furthermore, partial least squares-discriminant analysis was performed to compare the diagnostic performances of Raman spectroscopy for the classification of disease samples and healthy samples. Compared with existing diagnostic techniques, the Raman spectroscopy technique has many advantages such as extremely low sample requirements, ease of use, and ideal screening procedures. Thus, Raman spectroscopy has great potential for development as a powerful tool for distinguishing between healthy and liver cancer serum samples. [ABSTRACT FROM AUTHOR]

Myopia is a globally emerging concern accompanied by multiple medical and socio-economic burdens with no well-established causal treatment to control thus far. The study of the genomics and transcriptomics of myopia treatment is crucial to delineate disease pathways and provide valuable insights for the design of precise and effective therapeutics. A strong understanding of altered biochemical pathways and underlying pathogenesis leading to myopia may facilitate early diagnosis and treatment of myopia, ultimately leading to the development of more effective preventive and therapeutic measures. In this review, we summarize current data about the genomics and transcriptomics of myopia in human and animal models. We also discuss the potential applicability of these findings to precision medicine for myopia treatment. [ABSTRACT FROM AUTHOR]

Background: Inhibition of hepatic lipogenesis is widely regarded as an effective treatment for metabolic-associated fatty liver disease (MAFLD), although numerous related drugs have failed to reach clinical application. The goal of this study is to identify a novel small compound that can effectively treat MAFLD. Methods: Primary hepatocytes were first exposed to palmitic acid and oleic acid, then treated with compounds prior to high through screening for cellular lipid content. The efficacy of these compounds was measured by Nile Red staining and triglyceride analysis. The potential cellular toxicity caused by these compounds was evaluated by CCK8 assay. qPCR and Western blot were used to determine expression of RNAs and proteins, respectively. The compound was intraperitoneally injected into diet-induced obese (DIO) mice to examine its efficacy in vivo. Results: We identified the dimethyl 1-methyl-2-thioxoindoline-3,3-dicarboxylate (TOIDC) as a powerful chemical to reduce cellular lipid with minimal cellular toxicity. When injected intraperitoneally, TOIDC effectively ameliorates MAFLD in DIO mice. Mechanically, TOIDC suppresses de novo lipogenesis through inhibiting sterol regulatory element-binding protein 1 (SREBP1). Conclusions: Our findings indicate that TOIDC could be a promising lead compound to develop new drugs to treat MAFLD. [ABSTRACT FROM AUTHOR]

A cobalt‐catalyzed cascade reaction of N‐aryl thiocarbamoyl fluorides and water has been developed, providing access to 3‐alkyl‐2(3H)‐benzothiazolones in 48–83% yields. This protocol for 3‐alkyl‐2(3H)‐benzothiazolones precludes bad‐smell and toxic reagents. Mechanistic studies suggest that the transformation proceeds through hydrolysis followed by dehydrogenative coupling to form C−S bond involving a radical process. [ABSTRACT FROM AUTHOR]

For the first time, cotton fiber-shaped Cu2O nanoparticles were prepared onto the surface of a commercial copper (Cu) foil via a very simple immersion method at room temperature in which the soaking solution only contained CuSO4, Na2S2O3, and a very little amount of 1-butyl-3-methylimidazolium trifluoroacetate. In this work, the current collectors prepared using 1 mM, 2 mM, and 3 mM Na2S2O3 were, respectively, nominated as current collectors a, b, and c. Interestingly, a cotton fiber-shaped spatial network structure assembled by a large number of 10-nm-sized nanoparticles was presented on the surface of current collector b. The initial discharge capacity (DC) at 0.1 A g−1 of electrode b, namely, the graphite electrode assembled using current collector b, was as high as 467 mAh g−1, almost 1.65 times larger than that of the conventional graphite electrode. Particularly, at 0.5 A g−1 after 10 cycles, the DC value of electrode b (105 mAh g−1) was still about 1.8 times higher than that of the conventional graphite electrode (59 mAh g−1). An immersion method for preparing Cu2O-modified Cu foil at room temperature is developed in this work, which is very meaningful to the development of the Cu foil-based commercial graphite electrode, since no additional energy consumptions and no variations of the electrode preparation process are required. [ABSTRACT FROM AUTHOR]

To solve the problem that the curing mechanism evolution of phenolic resin catalyzed by Ba(OH)2 remained unclear, the p-p methylene index, o-p methylene index, o-o methylene index, hydroxymethyl index, and ether index were introduced to quantitatively investigate the chemical structure of resin in the curing temperature range of 90–230°C. The chemical structures were investigated by variable temperature FT-IR. The gas products released with the increase of curing temperature were characterized by Thermogravimetry-Mass Spectrometry. The curing mechanism from 90°C to 230°C was concluded finally. The results show that the main reaction is the formation of the p-p methylene group in the range of 90–120°C. It is difficult to form the o-p methylene bridge at this stage. In the range of 120–160°C, the main reaction is the formation of the p-p methylene group. From 160°C to 190°C, the main reactions are the breaking of the ether bond, the formation of the carbonyl group and the propyl bridge. Above 190°C, the main reactions are polycondensation reaction among phenolic hydroxyl groups, and the formation reaction of carbonyl groups. The ether bond breaks completely above 230°C. This work provides a new method to investigate the curing mechanism. It is a benefit for the rational design of the curing process of phenolic resin-based composites. [ABSTRACT FROM AUTHOR]

An iron‐catalyzed intramolecular dehydrogenative C−S bond formation from 1‐aryl‐1‐alkyl‐3‐aroyl thioureas via FeCl3 as catalyst, Na2CO3 as base, and Na2S2O8 as oxidant has been developed. A variety of 3‐alkyl‐2‐(N‐aroyl)imino‐benzo[d]thiazolines are obtained in moderate to excellent yields with excellent chemoselectivity in an atom‐economic fashion. In addition, 1‐aryl‐1‐alkyl‐3‐aroyl thioureas have been synthesized from N‐aryl‐N‐alkyl thiocarbamoyl fluorides (sufur form S8) with aromatic amides under NaOH in moderate to good yields. [ABSTRACT FROM AUTHOR]

By now, as the promising high‐energy cathode materials of lithium‐ion batteries (LIBs), the high‐nickel LiNi0.8Co0.1Mn0.1O2 (NCM811) still have technical problems such as poor electrode‐electrolyte interface stability and sensitivity to H2O and HF in the electrolyte to be solved. In this work, isocyanoethyl methacrylate (IMA) containing −N=C=O group is developed as a bifunctional electrolyte additive through the film‐forming, H2O removal, and HF reduction to modify the electrode‐electrolyte interfaces and improve the performance of NCM811/graphite LIBs. After 450 cycles under the normal voltage range of 2.75 to 4.20 V, the capacity retention of the battery with 0.5 wt.% IMA additive increases from 50.7 % to 78.0 % compared to the battery without the additive. And under the high voltage range of 2.75 to 4.40 V, the capacity retention of the battery with IMA increases from 62.8 % to 81.9 % after 150 cycles. It is demonstrated that the IMA additive as the H2O and HF scavenger of electrolyte also facilitate the electrochemical oxidation‐reduction reactions on two electrodes to form high‐quality interfacial films, which stabilizes the anode and cathode interfaces and subsequently improves the cycling performance of the batteries. These results show that the electrolyte with IMA additive has promising prospects in the application of high‐nickel NCM‐based LIBs and provide the idea to evaluate the organic molecules containing −N=C=O group as the functional electrolyte additives as well. [ABSTRACT FROM AUTHOR]

Although obstructive sleep apnea (OSA) has been clinically reported to be associated with acute coronary syndrome (ACS), the pathogenesis between the two is unclear. Herein, we analyzed and screened out the prospective molecular marker. To explore the candidate genes, as well as signaling cascades involved in ACS related to OSA, we extracted the integrated differentially expressed genes (DEGs) from the intersection of genes from the Gene Expression Omnibus (GEO) cohorts and text mining, followed by enrichment of the matching cell signal cascade through DAVID analysis. Moreover, the MCODE of Cytoscape software was employed to uncover the protein–protein interaction (PPI) network and the matching hub gene. A total of 17 and 56 integrated human DEGs in unstable angina (UA) and myocardial infarction (MI) group associated with OSAs that met the criteria of |log2 fold change (FC)|≥ 1, adjusted P < 0.05, respectively, were uncovered. After PPI network construction, the top five hub genes associated with UA were extracted, including APP, MAPK3, MMP9, CD40 and CD40LG, whereas those associated with MI were PPARG, MAPK1, MMP9, AGT, and TGFB1. The establishment of the aforementioned candidate key genes, as well as the enriched signaling cascades, provides promising molecular marker for OSA-related ACS, which will to provide a certain predictive value for the occurrence of ACS in OSA patients in the future. [ABSTRACT FROM AUTHOR]

Based on Monte Carlo simulation, the magnetic properties of a mixed spin-1 and spin-3/2 Ising superlattice with alternate layers are studied. The effects of interlayer coupling and external magnetic field on the compensation behavior and hysteresis properties for the ferrimagnetic superlattice are investigated. The occurrence of a compensation point is found to be greatly affected by the interlayer coupling. In particular, various multiple hysteresis loops can be observed under certain system parameters. The calculated results agree well with available experimental and theoretical works. [ABSTRACT FROM AUTHOR]

Traditional methods for preparing N,N‐disubstituted thiocarbamates require highly toxic, flammable and volatile reagents, or their derivatives. Recently, we developed a general method for thiocarbamoyl fluorides from safe, cheap, and easily available starting materials. Reported reactions involving thioyl fluoride with nucleophiles are very scarce. In this report, copper catalyzed reaction of thiocarbamoyl fluorides with phenols/thiophenols/alcohols/thioalcohols under Na2CO3 at 50 °C or at 80 °C in CH3CN were first developed, affording the corresponding N,N‐disubstituted thiocarbamates in moderate to excellent yields. When alcohols are cheap and their boiling points are less than 120 °C or they are water‐soluble, CuCl catalyzed reaction of thiocarbamoyl fluorides with alcohols at 50 °C was also developed. The reaction has good functional group tolerance. Methoxy, methyl, chloro, bromo, nitro, even ester functional groups were all tolerated. Control reactions demonstrated that copper catalyst played the key role on the success of these novel reactions. [ABSTRACT FROM AUTHOR]

Vascular endothelial dysfunction plays a crucial role in the pathogenesis of cardiovascular diseases. Oxidative stress is a key pathophysiological mechanism underpinning endothelial dysfunction. Schisandrin C (Sch C), a dibenzocyclooctadiene derivative of Schisandra chinensis, has antioxidative properties. Here, we report the use of Sch C as a novel therapeutic for the treatment of angiotensin II (Ang II)-induced endothelial deficits and explore the underlying mechanisms and the target of Sch C. Our results demonstrated that Sch C treatment prevents aorta oxidative stress and improves relaxation in mice, challenged with subcutaneous infusion of Ang II. In addition, Sch C significantly ameliorates Ang II-induced oxidative stress in rat aortic endothelial cells. We then discovered that these antioxidative effects of Sch C are mediated through the induction of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Using an expression plasmid and molecular docking, we identified that Kelch-like ECH-associated protein-1 (Keap1), a negative regulator of Nrf2, is a target of Sch C. These findings provide evidence for the potential use of Sch C as an antioxidative agent for treatment of vascular endothelial deficits. [ABSTRACT FROM AUTHOR]

Activated hepatic stellate cells (HSCs) serve key roles in hepatic fibrosis by producing excessive extracellular matrix (ECM) components. Lipopolysaccharide (LPS) has been found to be associated with hepatic fibrogenesis through direct interactions with HSCs. Recently, the fibroblast growth factor receptor 1 (FGFR1) signalling system was identified as a key player in the process of liver fibrosis. In the present study it was evaluated whether FGFR1 mediated LPS-induced HSCs activation. In cultured cells, FGFR1 was inhibited by either siRNA silencing or by a small-molecule inhibitor in LPS-stimulated HSCs. The blockade of FGFR1 decreased LPS-induced nuclear factor-κB (NF-κB) activation, inflammatory cytokine release, fibrosis, and cell proliferation in HSCs. It was further indicated that LPS triggered FGFR1 phosphorylation via TLR4/c-Src. These findings confirmed the detrimental effect of FGFR1 activation in the pathogenesis of LPS-related HSC activation and revealed that FGFR1 may be an ideal therapeutic target for LPS-induced liver fibrosis. [ABSTRACT FROM AUTHOR]

Atherosclerosis is recognized at present as a chronic metabolic disease of the arteries that leads to multifocal plaque development. Previous studies have reported that acid fibroblast growth factor (aFGF) is a critical therapeutic regulator in numerous chronic metabolic disorders. However, there is currently no direct evidence indicating whether aFGF serves a therapeutic role in atherosclerosis. In the present study, the role of aFGF in atherosclerotic lesion development was investigated by examining high-fat diet (HFD)-fed apolipoprotein E (ApoE)−/− mice and parenteral administration of aFGF. Increased expression of aFGF and peroxisome proliferator-activated receptor α (PPARα) was observed during atherosclerotic lesion development. The parenteral delivery of aFGF facilitated the progression of atherosclerosis without altering serum lipid expression levels in HFD-fed ApoE−/− mice. Furthermore, it was demonstrated that aFGF increased the expression of PPARα and inflammatory cytokines. The present results provided evidence that aFGF accelerates the progression of atherosclerosis and suggested that aFGF may be a potential therapeutic target for the prevention of atherosclerosis development. [ABSTRACT FROM AUTHOR]

Reaction trio: The title reaction delivers CH functionalized pyrrole derivatives in moderate to good yields. This novel three‐component reaction provides both syn‐ and anti‐pyrrole derivatives having two contiguous stereocenters with good regio‐, diastereo‐, and enantioselectivity. This process represents the first highly enantioselective palladium‐carbenoid‐mediated reaction. [ABSTRACT FROM AUTHOR]

Reaktionstrio: Die Titelreaktion ergibt C ‐ H ‐ funktionalisierte Pyrrolderivate in mäßigen bis guten Ausbeuten; sowohl die syn ‐ als auch die anti ‐ Produkte mit zwei benachbarten Stereozentren sind mit guten Regio ‐ , Diastereo ‐ und Enantioselektivitäten zugänglich. Der Prozess ist die erste hoch enantioselektive Palladiumcarbenoid ‐ vermittelte Reaktion. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to assess the antioxidative activity of selenium-enriched Chrysomyia Megacephala (Fabricius) (C. megacephala) larvae powder (SCML) and its impact on the diversity and structure of intestinal microflora in a mouse model of D-galactose (D-gal)-induced oxidative damage. Methods: Sixty male ICR mice were equally randomized to a normal control (NC) group, a model group, a positive group, a low-dose SCML (L-SCML) group, a mid-dose SCML (M-SCML) group, and a high-dose SCML (H-SCML) group. Animals in NC and model groups received water, animals in the positive group received 40 mg/Kg vitamin E (VE), and those in the three SCML groups received SCML which include 300, 1000 and 3000 μg/Kg selenium (Se) respectively. An oxidative damage model induced by subcutaneous injection of D-gal for 6 weeks via the neck was established. Serum oxidative stress levels and tissue appearance were evaluated. Tissues oxidative stress levels were detected by commercially available kit. Nuclear erythroid 2-related factor (Nrf2) and gut microbiota were determined by western blot and high throughput sequencing 16S rRNA gene respectively. Results: An oxidative damage model was established successfully as represented by a significant elevation of malondialdehyde (MDA) and protein carbonylation, and inhibition of the antioxidants including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC) and glutathione (GSH). It was found that oxidative damage and histological alterations were attenuated, the expression of Kelch-like ECH-associated protein (Keap1) was decreased, and the expression of Nrf2 and hemeoxygenase-1 (HO-1) was increased after SCML treatment. In addition, significant changes were observed in the gut microbiota, including Proteobacteria and the ratio of Bacteroidetes to Firmicutes at the phylum level, as well as Helicobacter, Clostridium and Lactobacillus at the genus level. Conclusion: SCML exerted an antioxidative effect in vivo, probably by increasing the antioxidant activity and reducing the production of oxidation products via the Nrf2 signaling pathway. SCML could also redress the intestinal flora imbalance induced by oxidative stress. All these findings suggest that SCML could serve as a functional food and natural drug additive to protect the human body against oxidative damage. [ABSTRACT FROM AUTHOR]