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BACKGROUND: Isopropyl 4‐(2‐chloro‐6‐(1H‐1,2,4‐triazol‐1‐yl)benzamido)benzoate (TPB) was a 1,2,4‐triazole benzoyl arylamine derivative with excellent antifungal activity, especially against Gaeumannomyces graminis var. tritici (Ggt). Its mechanism of action was investigated by transmission electron microscopy (TEM) observation, assays of sterol composition, cell membrane permeability, intracellular ATP and mitochondrial membrane potential, and mPTP permeability, ROS measurement, RNA sequencing (RNA‐seq) analysis. RESULTS: TPB interfered with ergosterol synthesis, reducing ergosterol content, increasing toxic intermediates, and finally causing biomembrane disruption such as increasing cell membrane permeability and content leakage, and destruction of organelle membranes such as coarse endoplasmic reticulum and vacuole. Moreover, TPB destroyed the function of adenine nucleotide transferase (ANT), leading to ATP transport obstruction in mitochondria, inhibiting mPTP opening, inducing intracellular ROS accumulation and mitochondrial membrane potential loss, finally resulting in mitochondrial damage including mitochondria swelled, mitochondrial membrane dissolved, and cristae destroyed and reduced. RNA‐seq analyses showed that TPB increased the expression of ERG11, ERG24, ERG6, ERG5, ERG3 and ERG2 genes in ergosterol synthesis pathway, interfered with the expression of genes (NDUFS5, ATPeV0E, NCA2 and Pam17) related to mitochondrial structure, and inhibited the expression of genes (WrbA and GST) related to anti‐oxidative stress. CONCLUSIONS: TPB exhibited excellent antifungal activity against Ggt by inhibiting ergosterol synthesis and destroying ANT function. So, TPB was a novel compound with dual‐target mechanism of action and can be considered a promising novel fungicide for the control of wheat Take‐all. The results provided new guides for the structural design of active compounds and powerful tools for pathogen resistance management. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

An asymmetric transfer hydrogenation of 2‐oxazolones in the presence of a chiral diamine ruthenium catalyst with potassium formate as a hydrogen source and potassium carbonate as an additive in 2,2,2‐trifluoroethanol is described. A series of chiral 2‐oxazolidinones were obtained with 29%–95% yields and 86%–>99% ee's. Furthermore, gram‐scale synthesis of chiral 2‐oxazolidinone and its downstream derivatizations demonstrate the practicality of this method. [ABSTRACT FROM AUTHOR]

A one‐pot synthesis of fluorinated chiral alcohols from α‐bromoarylketones and fluoroalcohols is described. The fluorinated ketone intermediates were formed from α‐bromoarylketones with fluoroalcohols as nucleophiles and solvents, which were reduced subsequentially by adding a chiral Ru catalyst and a mixture of formic acid and triethyl amines (FA: TEA=1.1:1) as hydrogen donor to give 27 examples of fluorinated chiral alcohols in 60–93% yields and 85–98% ee values. Notably, K3PO4 acts as a base in nucleophilic substitution and an additive in reductive step to enhance the reactivity and enantioselectivity, which is crucial for constructing compatible conditions for one‐pot process. This one‐pot process is also applicable to gram‐scale synthesis. [ABSTRACT FROM AUTHOR]

A highly efficient transfer hydrogenation of α‐aryl selenomethyl ketones, using readily available chiral diamine‐derived ruthenium complex as a catalyst and a mixture of formic acid and triethylamine as a hydrogen source in dichloromethane under ambient conditions, is described. A wide range of chiral β‐hydroxy selenides was obtained in 90–99% ee values and moderate to good yields. The practicability is also demonstrated by a gram‐scale synthesis and downstream derivatization. [ABSTRACT FROM AUTHOR]

It is a great challenge to optionally access diverse hydroxylation products from a given substrate bearing multiple reaction sites of sp3 and sp2 C−H bonds. Herein, we report the highly selective divergent hydroxylation of alkylbenzenes by an engineered P450 peroxygenase driven by a dual‐functional small molecule (DFSM). Using combinations of various P450BM3 variants with DFSMs enabled access to more than half of all possible hydroxylated products from each substrate with excellent regioselectivity (up to >99 %), enantioselectivity (up to >99 % ee), and high total turnover numbers (up to 80963). Crystal structure analysis, molecular dynamic simulations, and theoretical calculations revealed that synergistic effects between exogenous DFSMs and the protein environment controlled regio‐ and enantioselectivity. This work has implications for exogenous‐molecule‐modulated enzymatic regiodivergent and enantioselective hydroxylation with potential applications in synthetic chemistry. [ABSTRACT FROM AUTHOR]

A set of in situ measurement equipment of large aperture strong light element based on the principle of laser scattering is established. The size and distribution of defects (damage points) can be judged by the laser scattering signal. The maximum scanning range is 700 mm*1000 mm. The type and size of defects are directly obtained by scanning the quartz sample with a diameter of 100 mm. The types of defects are pitting and scratches, and the width of the scratches and the diameter of the pitting are mostly in the range of 0–10μm. The processing time could reach 31.06s. The device can realize the on‐line in situ measurement of large aperture optical elements, and has the advantages of fast response speed and high measurement accuracy. [ABSTRACT FROM AUTHOR]

A novel approach for the synthesis of 2‐arylquinazolin‐4(3H)‐ones was developed. A series of title compounds were obtained with good functional group tolerance and good yields by I2/DMSO‐mediated intramolecular oxidative cross‐coupling of 2‐(benzylamino)benzamides to form C=N double bonds. This method was applicable for gram‐scale synthesis. A proposed reaction pathway based on some control experiments was also provided. [ABSTRACT FROM AUTHOR]

An asymmetric reductive amination of aryl N‐heteroaryl ketones with Benzyl Amines has been realized via one‐pot two‐step process, using p‐toluenesulfonic acid and chiral iridium complexes as catalysts, a mixture of formic acid/triethylamine as a reductant. Twenty‐three examples of chiral aryl N‐heteroaryl methylamines were obtained with good yields and up to 99% ee. [ABSTRACT FROM AUTHOR]

As the "world factory," China has the most massive anthropogenic atmospheric mercury (Hg) emissions in the world along with its intense production activities. The development of global society and economy, including technology development, consumption behavior evolution, population growth, and so on, would significantly affect China's production and thus the Hg emissions. Here we uncover critical global socioeconomic drivers of atmospheric Hg emission changes in China during 2005–2015. Results show that the transition of global economic structures (i.e., production and final demand structures) caused 179 tons of increase in China's atmospheric Hg emissions during this period if other factors remained constant, while the transition of foreign economic structures contributed as much as 83% (149 tons). More importantly, for the first time, we reveal the crucial role of production structure transition in foreign nations. The cumulative effect of foreign production structure transition during this period (93 tons) was larger than that of foreign final demand structure transition (56 tons). It is also far more extensive than the cumulative effect of China's production structure transition (9.5 tons). Previous studies on China's atmospheric Hg emissions driven by global final demand focused more on optimizing consumption behaviors. However, this study proves the significance of a greener global production structure for reducing anthropogenic atmospheric Hg emissions in China, thus implementing the Minamata Convention on Mercury. Plain Language Summary: Mercury (Hg) is a highly toxic pollutant with severe adverse impacts on human health. The Minamata Convention on Mercury was signed in 2013 to protect human beings and ecosystems with strict Hg‐control measures. China is the largest Hg emitter in the world, the center of the global Hg‐control campaign, due to its intense production activities. However, as the "world factory" in the global supply chains, productions in China, along with its Hg emissions, are significantly affected by the development and changes of the global society and economy. This study reveals the driving effects of the global economy changes on atmospheric Hg emissions in China during 2005–2015. We find that the global economic structure transition (including the structures of production and consumption) has driven the increments of China's atmospheric Hg emissions in this period, in which the economic structural changes in nations other than China contribute relatively more. In particular, the effects of foreign nations' production structure, representing the production efficiency, were more extensive than those of China's. This study proves that, for the success of the Hg‐control campaign in China and the whole world, all the nations should join hands to make the global production "greener." Key Points: We uncover the impacts of global economic structure transition on China's atmospheric mercury emissions from 2005 to 2015Effects of foreign economic structure (especially production structure) changes are larger than those of China in this periodHg‐control campaign in China would benefit from the world's joint efforts to promote the green transition of global production structures [ABSTRACT FROM AUTHOR]

The outbreak of COVID‐19, caused by severe acute respiratory syndrome coronavirus 2, started in December 2019, Wuhan, China. We aimed to figure out the time‐point and duration of using antiviral drugs for receiving the maximal effects in patients with COVID‐19. In this study, we enrolled 129 confirmed COVID‐19 mild to moderate patients who had been treated with antiviral drugs during their hospitalization in Wuhan Union Hospital China. The patients were divided into an early antiviral treatment group and late antiviral treatment group. The demographic data, laboratory tests, the virus clearance time, chest computed tomography scans, and so forth were extracted, calculated, and compared between two groups. Our data showed that the median time from illness onset to initiation of antiviral treatment was 6 days in all patients. The group with early antiviral treatment demonstrated 7 days shorter in the virus clearance time when compared to the group with late antiviral treatment. After virus clearance, the group with early antiviral treatment showed milder illness than the group with late antiviral treatment. Early antiviral treatment could effectively shorten the virus clearance time, and prevent the rapid progression of COVID‐19. Therefore, the COVID‐19 patients should receive combined therapies with antiviral treatment at an early stage. Highlights: The group with early antiviral treatment demonstrated 7 days shorter in the virus clearance time when compared to the group with late antiviral treatment, and the time was further shortened after optimizing the duration of antivirals medication.After virus clearance, the group with early antiviral treatment showed milder illness than the group with late antiviral treatment.Controlling the duration of antiviral medication within 7 days could effectively clear virus, and slow down the replication of the virus in the body. [ABSTRACT FROM AUTHOR]

Backgound: To figure out whether diabetes is a risk factor influencing the progression and prognosis of 2019 novel coronavirus disease (COVID-19).Methods: A total of 174 consecutive patients confirmed with COVID-19 were studied. Demographic data, medical history, symptoms and signs, laboratory findings, chest computed tomography (CT) as well the treatment measures were collected and analysed.Results: We found that COVID-19 patients without other comorbidities but with diabetes (n = 24) were at higher risk of severe pneumonia, release of tissue injury-related enzymes, excessive uncontrolled inflammation responses and hypercoagulable state associated with dysregulation of glucose metabolism. Furthermore, serum levels of inflammation-related biomarkers such as IL-6, C-reactive protein, serum ferritin and coagulation index, D-dimer, were significantly higher (P < .01) in diabetic patients compared with those without, suggesting that patients with diabetes are more susceptible to an inflammatory storm eventually leading to rapid deterioration of COVID-19.Conclusions: Our data support the notion that diabetes should be considered as a risk factor for a rapid progression and bad prognosis of COVID-19. More intensive attention should be paid to patients with diabetes, in case of rapid deterioration. [ABSTRACT FROM AUTHOR]

It is of desirability to prepare in situ self‐supporting electrocatalysts not only to meet application requirements but also to simplify the production process of working electrodes. In this work, oxygen‐containing free‐standing carbon cloth with abundant pores (e‐CC−H2) has been obtained through a facile two‐step electrochemical oxidation and hydrogen etching method. Compared to the previous activation strategies of carbon cloth (such as chemical activation), this method has the advantages of simplicity, time‐saving, low‐cost and energy‐saving. Benefiting from the abundance of defects and oxygen‐containing functional groups that are active sites for oxygen evolution reaction, the obtained e‐CC−H2 shows excellent electrocatalytic activity, with a low overpotential of 350 mV at a current density of 10 mA cm−2, a low Tafel slope (127 mV dec−1) and stable electrochemical activity. This strategy paves the way for the application of functionalized and flexible materials in the field of electrochemical energy storage. [ABSTRACT FROM AUTHOR]

An asymmetric transfer hydrogenation of 2‐oxo alkyl phosphinates in the presence of a chiral diamine ruthenium catalyst with HCOONa as a hydrogen source in aqueous 2,2,2‐trifluoroethanol under mild conditions gave a wide range of chiral 2‐hydroxyalkyl diarylphosphinates in enantiomeric excesses of 97–99% and in good yields. The absolute configuration of the products was determined to be R by single‐crystal X‐ray diffraction. [ABSTRACT FROM AUTHOR]

Summary: To investigate the distribution and diversity of the pathogens associated with Fusarium crown rot in the Huanghuai wheat‐growing region (HHWGR) of China, we collected wheat samples with symptomatic stem bases from seven provinces in the HHWGR between 2013 and 2016. A total of 1196 isolates obtained from 222 locations were identified as 9 Fusarium species based on morphological and molecular identification. Of these pathogen species, F. pseudograminearum was the dominant species. Furthermore, F. sinensis was isolated from the disease specimens and tested for virulence to wheat. The result of the pathogenicity revealed that an intraspecific differentiation existed in F. pseudograminearum; sequence analysis of the EF‐1α gene showed that 194 F. pseudograminearum isolates were differentiated into two distinct clades which closed to the strains from Australia and China respectively, but neither pathogenicity nor EF‐1α sequence was related to the geographic origins of these isolates. However, universal rice primers‐polymerase chain reaction showed a correlation with the geographical origins of the 194 isolates, which were divided into eight subclusters, the level of genetic diversity was higher within a geographical population than among the different populations. The results of these analyses can be directly used to facilitate disease monitoring and development of control strategies. [ABSTRACT FROM AUTHOR]

Furfural residue (FR) is utilized directly for bioethanol production without any pretreatment and detoxification. With only 10 FPU g−1 cellulase loading, the glucose yield of FR reached 86.4, 84.6 and 80.5% at solid loadings of 2, 10 and 20%, respectively. When FR is directly used for fermentation, the terminal ethanol concentration achieved at 41 and 57 g L−1 at solid loadings of 20% and 30% (w v−1), respectively. Washing with water enhanced the enzymatic hydrolysis and fermentation of FR. The terminal ethanol of furfural residue washed by 5 times water (WFR‐5) was 48 and 66 g L−1, higher than that from FR. The enhancement is mainly due to the removal of chemical inhibitors and increase of specific surface area. The scanning electron microscope (SEM) showed that FR contained fragmental structure, coarse surface and porous areas. Therefore, FR substrates represented good cellulase accessibility. It indicated that FR could be directly used for glucose and ethanol production without any further treatment. In addition, the quasi‐simultaneous enzymatic saccharification and combined fermentation (Q‐SSF) residues are characterized by fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TG). [ABSTRACT FROM AUTHOR]

Abstract: We report a unique strategy for the development of a H2O2‐dependent cytochrome P450BM3 system, which catalyzes the monooxygenation of non‐native substrates with the assistance of dual‐functional small molecules (DFSMs), such as N‐(ω‐imidazolyl fatty acyl)‐ l‐amino acids. The acyl amino acid group of DFSM is responsible for bounding to enzyme as an anchoring group, while the imidazolyl group plays the role of general acid–base catalyst in the activation of H2O2. This system affords the best peroxygenase activity for the epoxidation of styrene, sulfoxidation of thioanisole, and hydroxylation of ethylbenzene among those P450–H2O2 system previously reported. This work provides the first example of the activation of the normally H2O2‐inert P450s through the introduction of an exogenous small molecule. This approach improves the potential use of P450s in organic synthesis as it avoids the expensive consumption of the reduced nicotinamide cofactor NAD(P)H and its dependent electron transport system. This introduces a promising approach for exploiting enzyme activity and function based on direct chemical intervention in the catalytic process. [ABSTRACT FROM AUTHOR]

A metal‐free one‐pot synthesis of sulfonamides from readily available nitroarenes and arylsulfonyl chlorides promoted by diboronic acid in water has been described. Twenty‐one examples of arylsulfonamides were obtained in moderate to good yields. Notably, a disulfonamide was also prepared from dinitrobenzene by this method. In addition, this one‐pot process is applicable for gram‐scale synthesis. [ABSTRACT FROM AUTHOR]

Traffic matrix (TM) is extremely important in many networking operations. This paper proposes a novel approach of TM estimation in large-scale IP networks, termed as Advanced-Tomogravity method, which is based on a precise gravity model and the tomography method. First, the precise gravity model is proposed on the basis of the existing generalized gravity model by introducing a relativity factor vector parameter, which defines the relativity between the solution of the existing generalized gravity model and its real TM. The solution obtained from this precise gravity model is then refined by the basic model of the tomography method. By mathematical analysis, we give the explicit expression of the relativity factor vector parameter in the proposed precise gravity model by the Moore-Penrose inverse and the minimum-norm least-square solution. The vector parameter is subsequently determined with the aid of small amount of historical real data of TM. A general algorithm of the proposed approach is therefore designed. Finally, our approach is validated by simulation using the real data of the Abilene Network. The simulation results indicate that it reduces the relative errors to less than one-half, better tracks not only the dynamic fluctuations but also the overall mean behavior of traffic flow. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Here, a new class of quantum dots, that is, sulphur quantum dots (SQDs), which are synthesized by the phase interfacial reaction, is reported. The prepared SQDs are monodisperse with a narrow size distribution (average 1.6 nm in size), excellent aqueous dispersibility, ultrahigh photostability, and lowly toxicity. Because of abundant oxidized sulphur species on the surface of SQDs, the incorporation of TiO2 with SQDs results in a synergistic effect for the TiO2-based photocatalysts offering more effective environmental applications. It is demonstrated that SQDs-TiO2 nanocomposite can enhance the photocatalytic activity of producing hydrogen (enhancement factor for 191) in methanol-water system. The SQDs also can used as fluorescent probe for highly selective quantitative detection Fe3+ in an aqueous solution contained various metal ions. [ABSTRACT FROM AUTHOR]

The performances of five yeast strains under three levels of toxicity were evaluated using hydrolysates from lodgepole pine pretreated by Sulfite Pretreatment to Overcome the Recalcitrance of Lignocelluloses (SPORL). The highest level of toxicity was represented by the whole pretreated biomass slurry, while intermediate toxicity was represented by the hydrolysate with partial loading of pretreatment spent liquor. The zero toxicity was represented using the enzymatic hydrolysate produced from thoroughly washed SPORL lodgepole pine solids. The results indicate that strains D5A and YRH400 can tolerate the whole pretreated biomass slurry to produce 90.1 and 73.5% theoretical ethanol yield. Strains Y1528, YRH403, and FPL450 did not grow in whole hydrolysate cultures and were observed to have lower ethanol productivities than D5A and YRH400 on the hydrolysate with intermediate toxicity. Both YRH400 and YRH403 were genetically engineered for xylose fermentation but were not able to consume xylose efficiently in hydrolysate. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1076-1083, 2014 [ABSTRACT FROM AUTHOR]

ABSTRACT Carbon nanotube (CNT)/styrene-ethylene-butylene-styrene (SEBS) composites were prepared via a sequential process of (electrostatic adsorption assisted dispersion)-plus-(melt mixing). It was found that CNTs were uniformly embedded in SEBS matrix and a low percolation threshold was achieved at the CNT concentration of 0.186 vol %. According to thermal gravimetric analysis, the temperatures of 20% and 50% weight loss were improved from 316°C and 352°C of pure SEBS to 439°C and 463°C of the 3 wt % CNT/SEBS composites, respectively. Meanwhile, the tensile strength and elastic modulus were improved by about 75% and 181.2% from 24 and 1.6 MPa of pure SEBS to 42 and 4.5 MPa of the 3 wt % CNT/SEBS composite based on the tensile tests, respectively. Importantly, this simple and low-cost method shows the potential for the preparation of CNT/polymer composite materials with enhanced electrical, mechanical properties, and thermal stability for industrial applications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40227. [ABSTRACT FROM AUTHOR]

A low‐power frequency‐shift keying (FSK) demodulator capable of demodulating 5 Mbit/s data rate is presented. No high sampling clock is needed in this demodulator design, and thus the design not only greatly reduces the circuit complexity but also achieves a high data rate. It is suitable for a digital data transmission chain of wireless communication. [ABSTRACT FROM AUTHOR]

Optimized conditions using the optically active ligand PBL allow the approach to the title structure as scaffold of biological and pharmaceutical components. [ABSTRACT FROM AUTHOR]

An abstract on fused pyrimidine derivatives through the synthesis of quinazolinones from aminobenzamides and diketones in aqueous media is presented.

The performances of five yeast strains under three levels of toxicity were evaluated using hydrolysates from lodgepole pine pretreated by Sulfite Pretreatment to Overcome the Recalcitrance of Lignocelluloses (SPORL). The highest level of toxicity was represented by the whole pretreated biomass slurry, while intermediate toxicity was represented by the hydrolysate with partial loading of pretreatment spent liquor. The zero toxicity was represented using the enzymatic hydrolysate produced from thoroughly washed SPORL lodgepole pine solids. The results indicate that strains D5A and YRH400 can tolerate the whole pretreated biomass slurry to produce 90.1 and 73.5% theoretical ethanol yield. Strains Y1528, YRH403, and FPL450 did not grow in whole hydrolysate cultures and were observed to have lower ethanol productivities than D5A and YRH400 on the hydrolysate with intermediate toxicity. Both YRH400 and YRH403 were genetically engineered for xylose fermentation but were not able to consume xylose efficiently in hydrolysate., (© 2014 American Institute of Chemical Engineers.)