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1,3‐Bis(boronic) esters can be readily synthesized from alkylBpin precursors. Selective transformations of these compounds hold the potential for late‐stage functionalization of the remaining C−B bond, leading to a diverse array of molecules. Currently, there are no strategies available to address the reactivity and, more importantly, the controllable regiodivergent functionalization of 1,3‐bis(boronic) esters. In this study, we have achieved controllable regiodivergent alkynylation of these molecules. The regioselectivity has been clarified based on the unique chelation patterns observed with different organometallic reagents. Remarkably, this methodology effectively addresses the low reactivity of 1,3‐bis(boronic) esters and bridges the gap in radical chemistry, which typically yields only the classical products formed via stable radical intermediates. Furthermore, the compounds synthesized through this approach serve as potent building blocks for creating molecular diversity. [ABSTRACT FROM AUTHOR]

1,3‐Bis(boronic) esters can be readily synthesized from alkylBpin precursors. Selective transformations of these compounds hold the potential for late‐stage functionalization of the remaining C−B bond, leading to a diverse array of molecules. Currently, there are no strategies available to address the reactivity and, more importantly, the controllable regiodivergent functionalization of 1,3‐bis(boronic) esters. In this study, we have achieved controllable regiodivergent alkynylation of these molecules. The regioselectivity has been clarified based on the unique chelation patterns observed with different organometallic reagents. Remarkably, this methodology effectively addresses the low reactivity of 1,3‐bis(boronic) esters and bridges the gap in radical chemistry, which typically yields only the classical products formed via stable radical intermediates. Furthermore, the compounds synthesized through this approach serve as potent building blocks for creating molecular diversity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Tolfenpyrad and dinotefuran are two representative pesticides used for pest control in tea gardens. Their application may bring about a potential risk to the health of consumers. Therefore, it is essential to investigate the residue behavior, transfer and risk assessment of tolfenpyrad, dinotefuran and metabolites from tea garden to teacup. RESULTS: An effective analytical method was established and validated to simultaneously determine tolfenpyrad, dinotefuran and its metabolites (DN and UF) in tea. The average recoveries of tolfenpyrad, dinotefuran, DN and UF were in the range 72.1–106.3%, with relative standard deviations lower than 11.8%. On the basis of the proposed method, the dissipation of tolfenpyrad and dinotefuran in fresh tea leaves followed first‐order kinetics models with half‐lives of 4.30–7.33 days and 4.65–5.50 days, respectively. With application amounts of 112.5–168.75 g a.i. ha–1 once or twice, the terminal residues of tolfenpyrad and total dinotefuran in green tea were lower than 19.6 and 7.13 mg kg−1, respectively, and below their corresponding maximum residue limits. The leaching rates of tolfenpyrad and total dinotefuran during the tea brewing were in the ranges 1.4–2.3% and 93.7–98.1%, respectively. CONCLUSION: Tolfenpyrad and dinotefuran in tea were easily degraded. The RQc and RQa values for tolfenpyrad were 37.6% and 5.4%, which were much higher than for dinotefuran at 24.7% and 0.84%, respectively. The data indicated that there was no significant health risk in tea for consumers at the recommended dosages. The results provide scientific data regarding the reasonable use of tolfenpyrad and dinotefuran aiming to ensure safe tea consuption. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND Propiconazole is widely used to control fungal diseases in field crops, including celery and onion. The potential risk to the environment and human health has aroused much public concern. Therefore, it is significant to investigate the degradation behaviour, residue distribution, and dietary risk assessment of propiconazole in celery and onion. RESULTS: A sensitive analytical method for determination of propiconazole residue in celery and onion was established and validated through high‐performance liquid chromatography tandem mass spectrometry. The average recovery rate of propiconazole ranged from 85.7% to 101.8%, with a relative standard deviation of 2.1–6.3%. For the dissipation kinetics, the data showed that propiconazole in celery and onion was degraded, with half‐lives of 6.1–6.2 days and 8.7–8.8 days respectively. In the terminal residue experiments, the residues of propiconazole were below 4.66 mg kg−1 in celery after application two or three times and were below 0.029 mg kg−1 in onion after application of three or four times with an interval of 14 days under the designed dosages. The chronic and acute dietary exposure assessments for propiconazole were valued by risk quotient, with all values being lower than 100%. CONCLUSION: Propiconazole in celery and onion was rapidly degraded following first‐order kinetics models. The dietary risk of propiconazole through celery or onion was negligible to consumers. The study not only offers a valuable reference for reasonable usage of propiconazole on celery and onion, but also facilitates the establishment of maximum residue limits in China. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background. Situational interest is articulated theoretically as a construct associated with five dimensional sources: novelty, challenge, attention demand, exploration intention, and instant enjoyment. Aims. This study aimed to examine the influence of the dimensional sources on situational interest. It was hypothesised that the dimensional sources function differently to contribute to situational interest and that the influence of a source might be mediated by others. Sample. Two samples of 7th, 8th, and 9th grade students were used in the study. There were 281 students (57% male, 43% female) in the first sample and 191 (47% male, 53% female) in the second. Method. Students in Sample A evaluated situational interest and the dimensional sources in tasks of analysing jogging and gymnastic stunts on video. Those in Sample B evaluated them in tasks of learning basketball. Correlation and regression analyses and path analyses were used to test the theoretical model. Results. Instant Enjoyment determined situational interest. Exploration and Novelty had positive influences on situational interest via enhancing Instant Enjoyment. Challenge showed little influence. The path analyses for both samples confirmed the inter-dimensional mediation effects of the sources. Conclusion. The analysed data support the hypotheses. The dimensional sources had unequal influences on situational interest and the mediation effects among themselves at times strengthened or weakened each other's influences. The findings suggest that to increase situational interest, educators should offer students ample exploratory opportunities during student-task interaction that can lead to instant enjoyment for learning. [ABSTRACT FROM AUTHOR]

Organoboronates are synthetically useful and highly valuable building blocks in synthetic and medicinal chemistry. Two‐electron reactions allow for the rapid construction of organoboronates via nucleophilic 1,2‐boron shift of boron ate complexes or MIDA‐mediated 1,2‐boryl migration. Radical approaches through 1,2‐boron shift of neutral boronic esters or boron ate complexes have been demonstrated to be feasible, providing complementary methods to access these privileged scaffolds. In this Review, recent achievements are highlighted and future opportunities are discussed, with an emphasis on different operative modes of catalysis and reaction pathways. [ABSTRACT FROM AUTHOR]

This study firstly investigated the effects of cucurbitacin E (CuE), a tetracyclic triterpene compound from Cucurbitaceae, on the pharmacokinetics ( PK) and pharmacodynamics ( PD) of warfarin, a model CYP2C probe substrate, in the rat. In PK studies, the concentration of warfarin in blood samples was determined by HPLC- DAD, and the PK parameters were analysed using non-compartmental methods. In PD studies, the prothrombin time ( PT) in blood plasma at each sample point was measured via thromboplastin reagents. CuE treatment (50, 100 and 200 μg/kg, i.p.) decreased warfarin clearance (28-32%), increased the area under the curve ( AUC0-∞; 55-62%) and prolonged plasma half-life ( t1/2; 58-72%). At the same time, the anticoagulation effect of warfarin ( PTmax) was also significantly increased in the presence of CuE. These data demonstrated that CuE affected the PK and PD of warfarin, and these effects may be due to the inhibition of CYP2C activity by CuE. Hence, careful monitoring should be carried out during concomitant use of herbal products containing CuE with drugs that are metabolized by CYP2C enzymes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Thiamethoxam is widely used to control pests in Chinese kale, popularly consumed leafy vegetables. The potential risk to the environment and human health has aroused much public concern. Therefore, it is important to investigate the degradation behavior, residue distribution and dietary risk assessment of thiamethoxam in Chinese kale. RESULTS: A sensitive analytical method for determination of thiamethoxam and its metabolite clothianidin residue in Chinese kale was established and validated through a quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique with ultra‐performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS). The recoveries were 85.4–101.2% for thiamethoxam and 79.5–108.1% for clothianidin, with the relative standard deviations (RSDs) of 0.9–10.2% and 1.8–6.0%, respectively. For the dissipation kinetics, the data showed that thiamethoxam in Chinese kale was degraded with the half‐lives of 4.1 to 4.5 days. In the terminal residue experiments, the residues of thiamethoxam were 0.017–0.357 mg kg−1 after application 2–3 times with a preharvest interval (PHI) of 7 days under the designed dosages. The chronic and acute dietary exposure assessment risk quotient (RQ) values of thiamethoxam in Chinese kale for different Chinese consumers were 0.08–0.19% and 0.05–0.12%, respectively, and those of clothianidin were 0.01–0.04% and 0.02–0.04%, respectively, all of the RQ values were lower than 100%. CONCLUSION: Thiamethoxam in Chinese kale was rapidly degraded following first‐order kinetics models. The dietary risk of thiamethoxam and clothianidin through Chinese kale was negligible to consumers. The results from this study are important reference for Chinese governments to developing criteria for the safe and rational use of thiamethoxam, setting maximum residue levels (MRLs), monitoring the quality safety of agricultural products and protecting consumer health. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Ceramic samples with the nominal composition (1− x) BaTiO3+ x Ba3Ti2YO8.5 ( x=0−0.535) were prepared by the mixed oxide method. X-ray diffraction (XRD) analysis shows that the materials are of single phase with a cubic symmetry as x≤0.16. The compositions of the solid solutions ( x≤0.16) can be expressed equivalently as Ba(Ti1− yY y)O3−δ ( y≤0.122, y= x/(1+2 x)). For x>0.16, the materials are diphasic composites consisting of Ba(Ti1− yY y)O3 ( y=0.122) and Ba3Ti2YO8.5. The microstructure observation by scanning electron microscopy supports the XRD result. The dielectric behavior and phase transitions of the solid solutions ( x≤0.16) vary with different Y concentrations. The dielectric constant of the composites ( x>0.16) follows approximately the Lichteneker relation in a wide temperature range. [ABSTRACT FROM AUTHOR]

In this paper, a transmission‐type graphene plasmonic modulator by introducing off‐resonant Au structure is theoretically and experimentally investigated. It is found that the modulation efficiency and bandwidth could be dramatically enhanced compared with bare graphene plasmonic structure. The validity of this proposed method is verified both in the 1D and 2D graphene plasmonic structures: ribbons and holes. This work will open up a new path to design the high‐efficiency modulators, switches, and multispectral detectors. [ABSTRACT FROM AUTHOR]

In this work, a tribological performance analysis is numerically conducted for a surface‐textured ring‐deformed liner conjunction. In the analysis, three different distribution patterns of surface texture are designed and machined on the surface of ring. To evaluate the frictional properties of the textured rings under mixed lubrication regime, a transient lubrication model considering the oil film thermal effect is developed. Meanwhile, to evaluate the oil film consumption and the transition of lubrication condition in an engine cycle, an oil transport model is built to determine the boundary positions of lubrication zone. Based on the models, the oil consumption, MOFT (minimum oil film thickness), friction force, power loss, and FMEP (friction mean effective pressure) value of the textured ring are studied under different oil supplies. The frictional characteristics of the rings with various distribution patterns of surface texture are also analyzed and compared. The results show that the edge‐textured ring can improve the tribological performance significantly, and the improvement varies with the oil supply. [ABSTRACT FROM AUTHOR]

Summary: Although many biocontrol bacteria can be used to improve plant tolerance to stresses and to promote plant growth, the hostile environmental conditions on plant phyllosphere and the limited knowledge on bacterial colonization on plant phyllosphere minimized the beneficial effects produced by the biocontrol bacteria. Rhodopseudomonas palustris strain GJ‐22 is known as a phyllosphere biocontrol agent. In this paper, we described detailed processes of strain GJ‐22 colony establishment at various colonization stages. Four different types of bacterial colonies, Type 1, scattered single cells; Type 2, small cell clusters; Type 3, small cell aggregates; and Type 4, large cell aggregates, were observed in the course of bacterial colonization. We categorized bacterial colonization into four phases, which were, Phase I: bacterial colony exists as Type 1 and cell population reduced quickly; Phase II: Type 1 evolved into Type 2 and cell population remained steady; Phase III: Type 3 arose and replaced Type 2, and cell population expanded slowly; and Phase IV: Type 3 matured into Type 4 and cell population increased quickly. We have shown that the preferable location sites of bacterial aggregates on leaf phyllosphere are grooves between plant epidermal cells. Analyses of expressions of plant defence‐related genes showed that, starting from Phase III, bacterial cells in the Type 3 and Type 4 colonies produced unidentified signals to induce host defence against Tobacco mosaic virus infection. In addition, we determined the crucial role of aggregates formation of GJ‐22 cell on plant phyllosphere in terms of bacterial cell stress tolerance and ISR (induced systemic resistance) priming. To our knowledge, this is the first report focused on the colonization process of a phyllosphere biocontrol agent and gave a clear description on the morphological shift of bacterial colony on phyllosphere. [ABSTRACT FROM AUTHOR]

Abstract: One of the unique features of plasmonic resonances in graphene structures is the enabled tunability through external means. Up to now, electrical gating is extensively adopted to tune graphene plasmonic resonances. This method is, however, limited unfortunately only to graphene structures with electrical connections. Here, a simple and efficient method to tune graphene plasmonic resonances by ultraviolet illuminations in a dynamical and reversible way is demonstrated. It is purely an optical means and can be applied to all kinds of graphene structures without introducing electrodes, ion–gel, or conducting layers required in electrical gating, which is of great significance especially for isolated graphene structures. The optical tuning method could shed new light on graphene‐based tunable devices. [ABSTRACT FROM AUTHOR]

The histone acetyltransferase males-absent-on-the-first (MOF) acetylates the histone H4, a modification important for many biological processes, including chromatin organization, transcriptional regulation, DNA replication, recombination and repair, as well as autophagy. Depletion of MOF induces serious consequences because of the reduction of histone acetylation, such as nuclear morphological defects and cancer. Despite the critical roles of MOF in the nucleus, the structural or functional mechanisms of the nucleocytoplasmic transport of MOF remain elusive. Here, we identified novel importin α1-specific nuclear localization signals (NLSs) in the N-terminal of human MOF. The crystal structure of MOF NLSs in complex with importin α1 further revealed a unique binding mode of MOF, with two independent NLSs binding to importin α1 major and minor sites, respectively. The second NLS of MOF displays an unexpected α-helical conformation in the C-terminus, with more extensive contacts with importin α1 not limited in the minor site. Mutations of the key residues on MOF and importin α1 lead to the reduction of their interaction as well as the nuclear import of MOF, revealing an essential role of NLS2 of MOF in interacting with importin α1 minor site. Taken together, we provide structural mechanisms underlying the nucleocytoplasmic transport of MOF, which will be of great importance in understanding the functional regulation of MOF in various biological processes. [ABSTRACT FROM AUTHOR]

ABSTRACT: Aim: The aim of this study was to estimate the prevalence and risk factors of chronic kidney disease (CKD) in first-degree relatives (FDRs) of CKD patients. Methods: A cross-section study of first-degree relatives of CKD patients was conducted between November 2007 and March 2009 in southern China. A total of 1187 first-degree relatives (494 male and 693 female; mean age 41.26 years) of 419 CKD patients (194 male and 225 female; mean age 32.10 years) were reviewed and tested for haematuria, albuminuria and reduced glomerular filtration rate. CKD risk factors, including age, gender, body mass index, hypertension and the causes of index case were also investigated. CKD was diagnosed according to the criteria of the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative. Results: The prevalence of CKD in first-degree relatives of CKD patients was 29.7% (95% confidence interval [CI]: 27.1%-32.2%). After adjusting for all the potential confounders, older age, female gender, hypertension, hyperglycaemia, hyperuricaemia, hypertriglyceridemic, low level of high density lipoproteins, increased body mass index and nephrotoxic medications were independently associated with increased risk of CKD. Furthermore, relatives of index cases with chronic glomerulonephritis were at higher risk haematuria (ORs = 2.12, 95% CI: 1.45-3.10) compared with relatives of index cases with other kinds of renal diseases. Conclusion: The first-degree relatives of CKD patients are at high risk of CKD, especially those relatives of CKD patients with chronic glomerulonephritis. Screening in this high risk population might help to identify early CKD patients and make a proper intervention strategy to prevent the disease from quick progression. [ABSTRACT FROM AUTHOR]