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SUMMARY: Due to the chelation of phosphorus in the soil, it becomes unavailable for plant growth and development. The mechanisms by which phosphorus‐solubilizing bacteria activate immobilized phosphorus to promote the growth and development of woody plants, as well as the intrinsic molecular mechanisms, are not clear. Through the analysis of microbial communities in the rhizosphere 16S V3–V4 and a homologous gene encoding microbial alkaline phosphomonoesterase (phoD) in phosphate‐efficient (PE) and phosphate‐inefficient apple rootstocks, it was found that PE significantly enriched beneficial rhizobacteria. The best phosphorus‐solubilizing bacteria, Bacillus sp. strain 7DB1 (B2), was isolated, purified, and identified from the rhizosphere soil of PE rootstocks. Incubating with Bacillus B2 into the rhizosphere of apple rootstocks significantly increased the soluble phosphorus and flavonoid content in the rhizosphere soil. Simultaneously, this process stimulates the root development of the rootstocks and enhances plant phosphorus uptake. After root transcriptome sequencing, candidate transcription factor MhMYB15, responsive to Bacillus B2, was identified through heatmap and co‐expression network analysis. Yeast one‐hybrid, electrophoretic mobility shift assay, and LUC assay confirmed that MhMYB15 can directly bind to the promoter regions of downstream functional genes, including chalcone synthase MhCHS2 and phosphate transporter MhPHT1;15. Transgenic experiments with MhMYB15 revealed that RNAi‐MhMYB15 silenced lines failed to induce an increase in flavonoid content and phosphorus levels in the roots under the treatment of Bacillus B2, and plant growth was slower than the control. In conclusion, MhMYB15 actively responds to Bacillus B2, regulating the accumulation of flavonoids and the uptake of phosphorus, thereby influencing plant growth and development. Significance Statement: In the rhizosphere soil of apple rootstocks on different phosphorus‐efficient/inefficient rootstocks, there exist distinct microbial communities. MhMYB15 can respond to the rhizobacterium Bacillus B2, and interact with flavonoids (MhCHS2) and phosphate transport proteins (MhPHT1;15) to promote plant root development and phosphate absorption. [ABSTRACT FROM AUTHOR]

As the next generation of green power system, smart grids have gradually enhanced the operation efficiency of power system. Meanwhile, the application of communication and intelligent technologies make the power grid more vulnerable to the emerging cyber‐physical attacks, such as the false data injection attack (FDIA). Particularly, the deception property of the FDIA on the output measurement estimation can fool the current security mechanism without triggering an alarm. Motivated by this problem, this paper aims at developing a novel detection and recovery mechanism against FDIA in smart grid. Based on the established state space grid model derived from the three‐phase sinusoidal voltage equations, an improved principal component analysis (PCA)‐based detection method is proposed. By introducing the mathematical transformation principle method, the detection performance such as detection rate and false positive rate can be improved. To keep the stable running of power system, a genetic optimization algorithm‐based linear quadratic regulator (LQR) defense method is developed. In addition, to improve the response performance to external attacks, an artificial intelligence method named genetic optimization algorithm is introduced to optimize the robust performance of the proposed defense method. Finally, the simulation results on the IEEE 6‐bus and 118‐bus grid system demonstrate the superiority of the proposed genetic algorithm optimization‐based LQR defense method. [ABSTRACT FROM AUTHOR]

The development of selectivity control strategies based on external operational conditions without modification of catalyst is an attractive but challenging issue in photocatalysis. Herein we reported the substrate concentration‐switched selectivity in photocatalytic transfer hydrogenation of biomass‐derived aromatic aldehydes. With the same catalyst, hydrodeoxygenation was realized at low aldehyde concentration and reductive etherification was realized at high aldehyde concentration. Mechanistic studies revealed that the substrate concentration affected the electron density on catalyst, thus controlled the initial reduction of formyl group and types of intermediates. Competitive adsorption of these intermediates on the catalyst affected hydrogenolysis of C−O bonds in the later stage. This method is easy to handle, and achieved selective hydrogenation of diverse bio‐based aldehydes to corresponding deoxygenated products and unsymmetric ether products as potential fuel additives under mild conditions. This work sheds light on the effect of substrate concentration on the selectivity in photocatalysis. [ABSTRACT FROM AUTHOR]

Mitochondria are essential organelles that not only undergo dynamic morphological changes but also exhibit functional activities such as mitochondrial membrane potential (MMP). While super‐resolution techniques such as stimulated emission depletion (STED) nanoscopy can visualize the ultrastructure of mitochondria and the MMP probe can monitor mitochondria function, few dyes meet both demands. Here, a small molecule (MitoPDI‐90) based on perylene diimide with cationic groups is reported and used for mitochondrial STED imaging and MMP indication. Characterized by excellent photostability, biocompatibility, and high quantum yield, MitoPDI‐90 exhibits STED imaging compatibility, facilitating visualization of mitochondrial cristae and time‐lapse imaging of highly dynamic mitochondria in living cells. Besides, MitoPDI‐90 targets the mitochondria through electrical potential, also enabling live‐cell MMP monitoring. MitoPDI‐90 allows for super‐resolution visualization and time‐lapse imaging of mitochondria, and more importantly, indication of changes in MMP, providing insight into the functional activity of live‐cell mitochondria. [ABSTRACT FROM AUTHOR]

Computational hemodynamics is being developed as an alternative approach for assisting clinical diagnosis and treatment planning for liver diseases. The technology is non‐invasive, but the computational time could be high when the full geometry of the blood vessels is taken into account. Existing approaches use either one‐dimensional model of the artery or simplified three‐dimensional tubular geometry in order to reduce the computational time, but the accuracy is sometime compromised, for example, when simulating blood flows in arteries with plaque. In this work, we study a highly parallel method for the transient incompressible Navier–Stokes equations for the simulation of the blood flows in the full three‐dimensional patient‐specific hepatic artery, portal vein and hepatic vein. As applications, we also simulate the flow in a patient with hepatectomy and calculate the S (PPG). One of the advantages of simulating blood flows in all hepatic vessels is that it provides a direct estimate of the PPG, which is a gold standard value to assess the portal hypertension. Moreover, the robustness and scalability of the algorithm are also investigated. A 83% parallel efficiency is achieved for solving a problem with 7 million elements on a supercomputer with more than 1000 processor cores. [ABSTRACT FROM AUTHOR]

Background: Mutations in mitochondrial tRNA (mt‐tRNA) genes are associated with hypertension, although their pathogenic mechanisms remain poorly understood. Methods: In the present study, two Han Chinese families with maternally transmitted hypertension were interviewed. The mtDNA mutations of matrilineal relatives were screened by polymerase chain reaction‐Sanger sequencing. Mitochondrial ATP, membrane potential and reactive oxygen species (ROS) were also analyzed in polymononuclear leukocytes carrying these mt‐tRNA mutations. Additionally, the levels of oxidative stress‐related biomarkers [malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px) and 8‐hydroxy‐2‐deoxyguanosine (8‐OHdG)] were analyzed. Results: Nine of 13 adult matrilineal relatives of these pedigrees exhibited a wide range of severity of hypertension. The age at onset of hypertension was 30–62 years (average 46 years). Mutational screening of mitochondrial genomes revealed tRNAArg T10410C and T10454C mutations. Indeed, the m.T10454C and m.T10410C mutations occurred at conserved bases of TΨC‐loop and acceptor arm of tRNAArg (positions 55 and 6), which are critical for tRNAArg post‐transcriptional modification. Thus, the defects in tRNA modification may cause failure in tRNA metabolism, impairing mitochondrial translation. Biochemical analysis revealed that m.T10454C or m.T10410C mutation significantly reduced mitochondrial ATP and membrane potential and also increased ROS production in mutant cell lines (all p < 0.05). In addition, the levels of MDA and 8‐OHdG in hypertensive patients markedly increased, whereas those of SOD and GSH‐Px decreased (all p < 0.05). Conclusions: These findings demonstrate that m.T10410C and m.T10454C mutations affect the structure and function of tRNAArg and consequently alter mitochondrial function and lead to oxidative stress, which are involved in the pathogenesis of maternally inherited hypertension. [ABSTRACT FROM AUTHOR]

BACKGROUND: The chiral pesticide bitertanol has been widely used in the prevention and treatment of fungal diseases on many crops. However, research on bitertanol at the stereoisomer level has not been reported. Here, we study the stereoselective bioactivity, toxicity, and degradation of this pesticide under laboratory and field conditions. RESULT: (1S,2R)‐Bitertanol was the most effective stereoisomer, showing 4.3–314.7 times more potent bioactivity than other stereoisomers against eight target pathogenic fungi. (1S,2R)‐Bitertanol showed 10.2 times greater inhibition of Botrytis cinerea spore germination than (1R,2S)‐bitertanol. According to the receptor‐drug docking results, the distances from the nitrogen atom in the heterocycle of (1S,2R)‐, (1R,2S)‐, (1R,2R)‐, and (1S,2S)‐bitertanol to the central Fe + atoms in the ferriporphyrin were 2.5, 3.8, 2.6, and 3.8 Å, respectively. (1S,2S)‐Bitertanol was 1.6–2.7 times more toxic than (1R,2R)‐bitertanol to Chlorella pyrenoidosa. The half‐lives of (1R,2S)‐, (1S,2R)‐, (1R,2R)‐, and (1S,2S)‐bitertanol were 3.7, 4.1, 4.1, and 4.8 d, respectively, in tomato. CONCLUSION: The stereoselective bioactivity, toxicity, and degradation for bitertanol were first studied here. (1S,2R)‐Bitertanol was a high efficiency and low toxicity stereoisomer. Moreover, the stereoselective bioactivity among all stereoisomers correlated with the binding distances and calculated energy differences between stereoisomers and the target protein. This study also provides a foundation for a systematic evaluation of bitertanol at the stereoisomer level. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This letter presents a robust active contour model driven by the local threshold preprocessing fitting energies to actualize fast segmentation of inhomogenous images. First, the local threshold preprocessing is carried out to compute two local intensity means. Second, these two means are sorted and serve as the local area fitting centres, which makes the contour move along the internal or external target boundaries. Finally, the above local area fitting centres are used to build the model's energy functional based on the symmetric cross entropy. Experimental results of the real inhomogenous images confirm that the presented model can segment inhomogenous images much faster and is robust to the setting up of the original contour. [ABSTRACT FROM AUTHOR]

Intensive agricultural activities have caused land degradation due to soil pollution, particularly by pesticides. However, the degradation, metabolism, and toxicity of chiral pesticides by soil microorganisms are often enantioselective. This study aimed to determine the effect of chirality on the degradation of the enantiomers of ethiprole in soil and their impact on soil microbial communities. (R)‐ethiprole underwent directional chiral conversion to the (S)‐enantiomer in a paddy soil microcosm, leading to elevated concentrations of (S)‐ethiprole. Initially, the bacterial operational taxonomic units significantly decreased after 3 days of incubation with rac‐ethiprole, (R)‐ethiprole, and (S)‐ethiprole but gradually increased in the later stage. Principal coordinate analysis revealed that the bacterial community structure was enantioselectively affected by the ethiprole enantiomers. Within 3 days, both rac‐ethiprole and (R)‐ethiprole reshaped the original stochastic microbial community into a deterministic community (variable selection). Thus, we propose that the enantioselective behavior and ecotoxicology of chiral pesticides need to be considered, especially because there are numerous chiral pesticides currently in use within agricultural management. The comprehensive understanding of the ecological risk of chiral pesticide enantiomers is vital to the process of improving sustainable production and environmental health in agricultural ecosystems. [ABSTRACT FROM AUTHOR]

A reversed‐phase simultaneous determination method for the enantiomers of carfentrazone‐ethyl and its metabolite carfentrazone in agricultural and environmental samples was established using high‐performance liquid chromatography‐tandem mass spectrometry. A complete enantioseparation of carfentrazone‐ethyl and its chiral metabolite carfentrazone enantiomers was obtained using a chiral column. The absolute configuration and specific optical rotation of carfentrazone‐ethyl and carfentrazone enantiomers were first confirmed as peaks 1, 2, 3, and 4: S‐(+)‐carfentrazone, R‐(‐)‐carfentrazone, S‐(‐)‐carfentrazone‐ethyl, and R‐(+)‐carfentrazone‐ethyl, respectively. The specificity, matrix effect, linearity, precision, accuracy, and stability were surveyed to evaluate the feasibility of the method. The mean recovery was in the range of 77.5–102.8% with relative standard deviations of 0.4‐9.8% for the samples. The limits of detection of the enantiomers were evaluated as 0.7 to 6.0 μg/kg, and the limits of quantification were 2.5 to 20 μg/kg. The stereoselective degradation of carfentrazone‐ethyl and carfentrazone in rice plant was investigated, and there was no clear enantioselectivity for carfentrazone‐ethyl. As for carfentrazone, the enantiomer fractions value reached 0.85 at 7 days after spraying. The developed method was simple and reliable enough for the corresponding risk assessment of carfentrazone‐ethyl and its metabolite enantiomers in crop plants, cereal grains, and soil samples. [ABSTRACT FROM AUTHOR]

l-Valine, l-leucine, l-isoleucine, l-phenylalanine, and l-tyrosine are important proposed biomarkers for the early detection and diagnosis of type 2 diabetes. A simple and selective hydrophilic interaction chromatography with tandem mass spectrometry method was developed for the simultaneous determination of these amino acids in human serum, using stable isotope-labeled amino acids as internal standards. Chromatographic separation was carried out on a Syncronis HILIC column (150 mm × 2.1 mm, 5 μm) with the column temperature of 35°C and a mobile phase consisted of acetonitrile/120 mM ammonium acetate (89:11, v/v), and the run time was 11.0 min. The mass spectrometric analysis was performed using a QTRAP 5500 mass spectrometer coupled with an electrospray ionization source in positive ion mode. As these five amino acids are endogenous compounds in serum, we used the corresponding stable isotope-labeled amino acids to evaluate the matrix effect and recovery in serum. The matrix effect was 98.7-107.3%, and the recovery was 92.7-102.3%. Calibration curves spiked unlabeled amino acids in water were linear over the range of 0.200-100 μg/mL. The accuracy, inter-, and intraday precision were below 10.2%. Analytes were stable during the study. This assay method has been validated and applied to the early diagnosis research of type 2 diabetes. [ABSTRACT FROM AUTHOR]

BACKGROUND To date, no research has been conducted to establish exposure levels for occupational pesticide operators under typical use scenarios in China. Through surrogate skin techniques (the whole-body method), the authors monitored dermal and inhalation exposure of pesticide applicators in China. In addition, the exposure of pesticide mixers was analysed. RESULTS The total dermal exposure of inexperienced and experienced applicators was respectively 4037 and 536 mg kg−1 of active ingredient ( AI) handled for application to maize that was <80 cm in height. The exposure level was highest on hands; the closer to the hands, the lower arms and the upper legs, the higher the exposure. The unit exposure of mixers differed according to the formulation; exposure to emulsifiable concentrate ( EC) and oil-in-water emulsion ( EW) was greater than exposure to wettable powder ( WP) or wettable dispersible granules ( WG). The unit exposure of mixers via inhalation was significantly greater than that of applicators when chlorpyrifos (48% EC) was used ( P < 0.0001). CONCLUSIONS The main objectives of this study were to provide an indication of the realistic exposure risk of mixers and applicators, and to contribute useful information for risk mitigation and management and epidemiological studies in China. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Atrazine is a long-lasting herbicide that has been shown to affect hormone levels in amphibians. Using the C-13 labeled atrazine to detect its residue is effective and essential. This study presents three steps for the synthesis of [13C3]atrazine, which starts from [13C]urea, and results in the incorporation of C-13 atoms at the 1, 3 and 5 positions of the S-triazine ring of atrazine. The method prepares the product in an overall yield of 57.6% and chemical purity of 98.6%, for use as an internal standard. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background Long-term antithrombotic strategies for patients with chronic coronary syndrome with high-risk factors represent an important treatment dilemma in clinical practice. Our aim was to conduct a network meta-analysis to evaluate the efficacy and safety of long-term antithrombotic strategies in patients with chronic coronary syndrome. Methods and Results Four randomized studies were included (n=75167; THEMIS [Ticagrelor on Health Outcomes in Diabetes Mellitus Patients Intervention Study], COMPASS [Cardiovascular Outcomes for People Using Anticoagulation Strategies], PEGASUS-TIMI 54 [Prevention of Cardiovascular Events in Patients With Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin-Thrombolysis in Myocardial Infarction 54], and DAPT [Dual Anti-platelet Therapy]). The odds ratios (ORs) and 95% CIs) were calculated as the measure of effect size. The results of the network meta-analysis showed that, compared with aspirin monotherapy, the ORs for trial-defined major adverse cardiovascular and cerebrovascular events were 0.86; (95% CI, 0.80-0.93) for ticagrelor plus aspirin, 0.89 (95% CI, 0.78-1.02) for rivaroxaban monotherapy, 0.74 (95% CI, 0.64-0.85) for rivaroxaban plus aspirin, and 0.72 (95% CI, 0.60,-0.86) for thienopyridine plus aspirin. Compared with aspirin monotherapy, the ORs for trial-defined major bleeding were 2.15 (95% CI, 1.78-2.59]) for ticagrelor plus aspirin, 1.51 (95% CI, 1.23-1.85) for rivaroxaban monotherapy, and 1.68 (95% CI, 1.37-2.05) for rivaroxaban plus aspirin. For death from any cause, the improvement effect of rivaroxaban plus aspirin was detected versus aspirin monotherapy (OR, 0.76; 95% CI, 0.65-0.90), ticagrelor plus aspirin (OR, 0.79; 95% CI, 0.66-0.95), rivaroxaban monotherapy (OR, 0.82; 95% CI, 0.69-0.97), and thienopyridine plus aspirin (OR, 0.58; 95% CI, 0.41-0.82) regimens. Conclusions All antithrombotic strategies combined with aspirin significantly reduced the incidence of major adverse cardiovascular and cerebrovascular events and increased the risk of major bleeding compared with aspirin monotherapy. Considering the outcomes of all ischemic and bleeding events and all-cause mortality, rivaroxaban plus aspirin appears to be the preferred long-term antithrombotic regimen for patients with chronic coronary syndrome and high-risk factors.