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Di-(2-ethylhexyl) phthalate (DEHP) is used in food packaging and medical products, resulting in unintentional human ingestion. Concurrently, a high fat (HF)-oriented diet is very popular for many people worldwide. Here we investigated the regulatory role of renin-angiotensin system in kidney dysfunction. The HF diet-fed rats were fed a HF diet plus different doses of 10, 100 and 300 mg/kg bw DEHP for 35 days by gavage. Serum lipid contents and protein activities of renin-angiotensin system (RAS) components were measured using biochemical methods and ELISA; key metabolic genes and proteins of the kidney were determined by RT-PCR and western blotting techniques. Kidney morphology was examined through hematoxylin-eosin (HE) staining. Kidney weight to body weight ratio and mRNA expression of kidney damage markers were significantly increased following DEHP plus HF administration, which corresponded histologically with glomerular basement membrane thickening and glomerular swelling. Furthermore, DEHP treatment plus a HF diet induced dyslipidemia, accompanied by increased levels of renin-angiotensin system components, such as ACE protein, MAS-1 protein, serum renin and aldosterone. In addition, mRNA expression levels of pro-inflammatory cytokines were significantly upregulated in the kidneys. Pearson correlation analysis revealed that higher kidney ACE expression and ACE/ACE-2 ratio were positively associated with TG, TC and LDL-C levels. These data suggest that combined exposure to DEHP exposure plus a HF diet feeding may induce renal damage through overactivation of RAS. [ABSTRACT FROM AUTHOR]

Due to the roadside unit can not fully achieve seamless coverage and the dynamic change of network topology in vehicular networks, problems such as the interruption of vehicle service, poor stability of communication link, and high network delay will be caused. To solve these problems, this paper proposes a codirectional multilane adaptive message return (CMAMR) strategy based on edge computing. Firstly, we establish a CMAMR communication model. Then, according to the movement trajectory of the receiving node, we propose a single-hop and a multi-hop message return link strategy. The former combines the single-hop link quality and node location information to construct a node selection function to assist the head node in selecting an optimal forwarding node to form a single-hop message return link. The latter assists the RSU to select the optimal multi-hop message return link in the same lane by establishing a link adaptive quality evaluation function, thus improving the user's quality of server. The simulation results show that the link network delay of the CMAMR strategy is 14.6%, 42.86%, and 38.47% lower than those of the random with forwarding progress (RFP), most forward with fixed radius (MFR), and traditional vehicle-to-infrastructure and vehicle-to-vehicle cooperative communication (TVCC) message return strategies, respectively; correspondingly, the link reliability is at least 9.13% higher for the CMAMR strategy. [ABSTRACT FROM AUTHOR]

To solve the problems of unbalanced network loads, poor network throughput, and low user transmission rate in 5th generation (5G) vehicular networks, a user‐centric data communication service (UCDCS) strategy is proposed for 5G vehicular networks. First, the UCDCS model is established. The access roadside unit group (ARSUG) is updated in real‐time according to predictions of vehicle mobility. Then, a data communication service resource allocation algorithm based on game theory that considers the network load cost, throughput cost, and vehicle benefit is developed. Based on the results of the algorithm, roadside unit (RSU) selection based on entropy weight is performed and the best RSU for data communication is selected according to the different service preferences of each vehicle. This improves the transmission rate for users and realizes network load balance to ensure the quality of service for users. The simulation results show that the transmission rate of the UCDCS strategy is 35.16%, 23.46%, and 47.74% higher than those of the traditional handover management (THOM), improved mobility management (IMM), and network‐centric network selection strategies (NCNS), respectively; correspondingly, the link reliability is at least 0.07% higher, and the network delay is at least 5.96% smaller for the UCDCS strategy. [ABSTRACT FROM AUTHOR]

Missing data and outliers usually arise in longitudinal studies. Ignoring the effects of missing data and outliers will make the classical generalized estimating equation approach invalid. The longitudinal cohort study of rheumatoid arthritis patients was designed to investigate whether the Health Assessment Questionnaire score was associated with baseline covariates and changed with time. There exist dropouts and outliers in the data. In order to analyze the data, we develop a robust estimating equation approach. To deal with the responses missing at random, we extend a doubly robust method. To achieve robustness against outliers, we utilize an outlier robust method, which corrects the bias induced by outliers through centralizing the covariate matrix in the estimating equation. The doubly robust method for dropouts is easy to combine with the outlier robust method. The proposed method has the property of robustness in the sense that the proposed estimator is not only doubly robust against model misspecification for dropouts when there is no outlier in the data, but also robust against outliers. Consistency and asymptotic normality of the proposed estimator are established under regularity conditions. A comprehensive simulation study and real data analysis demonstrate that the proposed estimator does have the property of robustness. [ABSTRACT FROM AUTHOR]

Instrumental variables are widely used to deal with unmeasured confounding in observational studies and imperfect randomized controlled trials. In these studies, researchers often target the so-called local average treatment effect as it is identifiable under mild conditions. In this paper we consider estimation of the local average treatment effect under the binary instrumental variable model. We discuss the challenges of causal estimation with a binary outcome and show that, surprisingly, it can be more difficult than in the case with a continuous outcome. We propose novel modelling and estimation procedures that improve upon existing proposals in terms of model congeniality, interpretability, robustness and efficiency. Our approach is illustrated via simulation studies and a real data analysis. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM2.5) increases the risks of lung cancer. Epigenetics provides a new toxicology mechanism for the adverse health effects of PM2.5. However, the regulating mechanisms of PM2.5 exposure on candidate gene DNA methylation changes in the development of lung cancer remain unclear. Abnormal expression of the glutathione S transferase (GST) gene is associated with cancer. However, the relationship between PM2.5 and DNA methylation-mediated GST gene expression is not well understood. In this study, we performed GST DNA methylation analysis and GST-related gene expression in human A549 cells exposed to PM2.5 (0, 50, 100 µg/mL, from Taiyuan, China) for 24 h (n = 4). We found that PM2.5 may cause DNA oxidative damage to cells and the elevation of GSTP1 promotes cell resistance to reactive oxygen species (ROS). The Kelch-1ike ECH-associated protein l (Keap1)/nuclear factor NF-E2-related factor 2 (Nrf2) pathway activates the GSTP1. The decrease in the DNA methylation level of the GSTP1 gene enhances GSTP1 expression. GST DNA methylation is associated with reduced levels of 5-methylcytosine (5mC), DNA methyltransferase 1 (DNMT1), and histone deacetylases 3 (HDAC3). The GSTM1 was not sensitive to PM2.5 stimulation. Our findings suggest that PM2.5 activates GSTP1 to defend PM2.5-induced ROS and 8-hydroxy-deoxyguanosine (8-OHdG) formation through the Keap1/Nrf2 signaling pathway and GSTP1 DNA methylation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oil soluble CDs (o-CDs) with blue fluorescence were fabricated via pyrolysis. • o-CDs have excellent quantum yield and good photostability. • The o-CDs-based fluorescence probe was established to detect doxycycline. • o-CDs were successfully applied in the detection of doxycycline in milk. • o-CDs serve as fluorescence ink and work as fluorescence film. The overuse of doxycycline poses a risk for ecological environment. Advanced materials such as anti-counterfeiting and photovoltaic materials are urgently needed to develop innovative strategies for exploiting solar cells and protecting valuable products. Herein, oil-soluble CDs (o-CDs) were successfully fabricated from citric acid, tris-base and oleylamine as precursors via pyrolysis method. The o-CDs with uniform size distribution exhibited a high quantum yield of 0.48 and excellent photostability. The fluorescence of o-CDs was rapidly quenched by doxycycline at room temperature without further modification. Optimal conditions were selected to construct a fluorescence probe with high selectivity and good sensitivity to detect doxycycline. Interestingly, the probe achieved two linear ranges of 0.85––16.7 µM and 16.7––33.4 µM with a low detection limit of 0.26 µM. Furthermore, inner filter effect (IFE) was dominated in the process in which doxycycline interact with the oxygen-containing groups of o-CDs. This sensing platform has been further successfully applied to the detection of doxycycline in milk with recovery rates of 96.8%- 102.7% and relative standard deviations of 0.98%- 1.02%, suggesting that the novel probe has the potential to be applied in real samples. Moreover, o-CDs directly serve as fluorescence ink and work as fluorescence film using PVA as matrix because of strong fluorescence in the solid state, indicating that they have potential applications in anti-counterfeiting and photovoltaic materials. This is the first report that oil-soluble CDs via pyrolysis is applied in the detection of doxycycline in milk. Importantly, this work provides efficient strategies for the construction of anti-counterfeiting and photovoltaic materials. [ABSTRACT FROM AUTHOR]

Abstract Measurement errors and outliers commonly arise during the process of longitudinal data collection and ignoring them in data analysis can lead to large deviations in estimates. Therefore, it is important to take into account the effect of measurement errors and outliers in longitudinal data analysis. In this paper, a robust estimating equation method for analyzing longitudinal data with covariate measurement errors and outliers is proposed. Specifically, the biases caused by measurement errors are reduced via using the independence between replicate measurements and the biases caused by outliers are corrected via centralizing the observed covariate matrix. The proposed method does not require specifying the distributions of the true covariates, response and measurement errors. In practice, it can be easily implemented via the standard generalized estimating equations algorithms. The asymptotic normality of the proposed estimator is established under regularity conditions. Extensive simulation studies show that the proposed method performs better in handling measurement errors and outliers than several existing methods. For illustration, the proposed method is applied to a data set from the Lifestyle Education for Activity and Nutrition (LEAN) study. [ABSTRACT FROM AUTHOR]

Simple and inexpensive polyhalides (CCl4 and C2Cl6) have been found to be effective and versatile oxidants in removing electrons from Breslow intermediates under N-heterocyclic carbene (NHC) catalysis. This oxidative reaction involves multiple single-electron-transfer (SET) processes and several radical intermediates. The α, β, and γ-carbon atoms of aldehydes and enals could be readily functionalized. Given the low cost of the oxidants and the broad applicability of the reactions, this study is expected to greatly enhance the feasibility of oxidative NHC catalysis for large-scale applications. Also this new SET radical process with polyhalides as single-electron oxidants will open a new avenue in the development of NHC-catalyzed radical reactions. [ABSTRACT FROM AUTHOR]

Simple and inexpensive polyhalides (CCl4 and C2Cl6) have been found to be effective and versatile oxidants in removing electrons from Breslow intermediates under N-heterocyclic carbene (NHC) catalysis. This oxidative reaction involves multiple single-electron-transfer (SET) processes and several radical intermediates. The α, β, and γ-carbon atoms of aldehydes and enals could be readily functionalized. Given the low cost of the oxidants and the broad applicability of the reactions, this study is expected to greatly enhance the feasibility of oxidative NHC catalysis for large-scale applications. Also this new SET radical process with polyhalides as single-electron oxidants will open a new avenue in the development of NHC-catalyzed radical reactions. [ABSTRACT FROM AUTHOR]

Sulfoxides are important functional molecules. We develop a short-route (one-pot) synthesis of this class of molecules by reacting thiols with alkenes or alkynes under mild and metal-free conditions. N-Fluorobenzenesulfonimide (NFSI) is used to play dual roles: as a radical initiator for a thiol–ene/–yne reaction to form sulfide adducts, and as efficient oxidant for conversion of the sulfides formed in situ to sulfoxides. Over-oxidation of the sulfoxides to sulfones is avoided in our approach. [ABSTRACT FROM AUTHOR]

The aim of the study is to investigate chemical compositions of fine chalk dust particles (chalk PM 2.5 ) and examine their adverse effects on alveolar macrophages (AMs) in vitro . Morphologies and element concentrations of individual chalk particles were analyzed by using the quantitative energy-dispersive electron probe X-ray microanalysis (ED-EPMA). The oxidative response of AMs and the potential to generate nitric oxide (NO) by luminol-dependent chemiluminescence (CL) and nitrate reductase method were assessed 4 h following the treatment of AMs with differing dosages of fine chalk particles, respectively. Oxidative stress and cytotoxicity elicited by chalk PM 2.5 were also examined. The results showed that fine chalk particles were mainly composed of gypsum, calcite, dolomite and a little amount of organic adhesives. Exposure to chalk PM 2.5 at 100 μg mL −1 or 300 μg mL −1 significantly increased intracellular catalase, malondialdehyde, and NO levels and decreased superoxide dismutase level in AMs, leading to leakage of lactate dehydrogenase (LDH) and reduction of the cell viability. Furthermore, luminol-dependent CL from respiratory burst in AMs was enhanced. It was suggested that chalk PM 2.5 could make oxidative damages on AMs and result in cytotoxicity, being likely attributed to excessive reactive oxygen species or reactive nitrogen species induced by mixture of fine gypsum and calcite/dolomite particles. [ABSTRACT FROM AUTHOR]

• We propose the L-SIRS information transmission model. • Propagation threshold and stability of equilibrium points are derived. • Two information transmission interference strategies are proposed. • Simulation results demonstrate the effectiveness and accuracy of the L-SIRS model. In complex network research, the infectious disease model is often used to study transmission mechanisms and interference factors of information; consequently, they are essential for the prediction and control of information transmission. The conventional SIRS epidemic model has a wide range of applications and is theoretically mature. However, it does not stratify the nodes in a network, and fails to reflect the characteristics of different nodes. To solve this problem, we propose a layered SIRS information transmission model (L-SIRS). Depending on the node influence, we assign the nodes in the network to high- and low-influence layers and establish an intra- and inter-layer information transmission mechanism. The transmission threshold and equilibrium point of this model are analyzed theoretically. To reduce the transmission of online public opinions, two kinds of information transmission interference strategies, namely, information blocking and information dredging, are designed to study their influence on information transmission. Finally, combine with practice, the simulation results indicate that the L-SIRS model can more accurately describe network information transmission and both information blocking and information dredging can effectively inhibit the spread of information. [ABSTRACT FROM AUTHOR]

Abstract: Sodium metabisulfite (SMB) is most commonly used as a food additives, however few study was performed on the vasodilator effect of SMB. In the present paper, the vasodilator effects of SMB and roles of Ca2+ and K+ channels as well as the cGMP pathway on isolated rat aortic rings were studied. The results show that: (1) SMB could relax isolated aortic rings precontracted by norepinephrine in a concentration-dependent manner. The maximal endothelium-dependent vasorelaxation was approximately 20% whereas that not depending on the presence of the endothelium was more than 90%. (2) The vasorelaxant effects induced by 50 or 200μM SMB were partially inhibited by iberiotoxin, NS-2028 or l-NNA. The vasorelaxation of 1000μM SMB was partially inhibited by nifedipine or glibenclamide. The SMB induced vasorelaxation was partially inhibited by tetraethylammonium. These results led to the conclusions that the vasorelaxation of SMB at low concentrations (<400μM) was endothelium-dependent and mediated by the cGMP pathway and BKCa channel, but at high concentrations (>500μM) was endothelium-independent and mediated by KATP channel and L-type Ca2+ channel. The maximal allowable concentration from China and the acceptable daily intake level from WHO of SMB as a food additive should be revised. [Copyright &y& Elsevier]

This work demonstrates a general and efficient method to prepare conjugated dienes by Pd(II)-catalyzed direct olefination of unactivated alkenes with allylic esters and acrylates via vinylic C–H activation. Various aryl and heteroaryl alkenes as well as aliphatic alkenes all give the desired linear 1,3-butadienes with retention of the traditional leaving groups such as OAc and other carboxylic acid ester groups. [ABSTRACT FROM AUTHOR]

Various aryl-substituted 1,4-benzoquinone derivatives have been prepared via a palladium-catalyzed decarboxylative cross-coupling of electron-rich aromatic acids with 1,4-benzoquinones. [ABSTRACT FROM AUTHOR]

Abstract: The detection and quantification of disease-related proteins play critical roles in clinical practice and diagnostic assays. We present an affinity probe capillary electrophoresis/laser-induced fluorescence polarization (APCE/LIFP) assay for detection of human thrombin using a specific aptamer as probe. In the APCE/LIFP assay, the mobility and fluorescence polarization of complex are measured simultaneously during CE analysis. The affinity complex of human thrombin can be well separated from unbound aptamer on CE and clearly identified on the basis of its fluorescence polarization and migration. Because of the binding favorable G-quartet conformation potentially involved in the specific aptamer, it was assumed that monovalent and bivalent cations promoting the formation of a stable G quadruplex conformation in the aptamer may enhance the binding of the aptamer and thrombin. Therefore, we investigated the effects of various metal cations on the binding of human thrombin and the aptamer. Our results show that cations like K+ and Mg2+ could not stabilize the affinity complex. Without the use of typical cations, a highly sensitive assay of human thrombin was developed with the corresponding detection limits of 4.38×10−19 and 2.94×10−19 mol in mass for standard solution and human serum, respectively. [Copyright &y& Elsevier]

Internet of Things (IoT) is a new concept in the information and communication technology studies which indicates that any creature (human, animal, or object) can send and receive data through communication networks, such as the internet or intranet platform. Wireless sensors have limited energy resources due to the use of batteries to supply energy, and since it is usually not possible to replace the batteries of these sensors. In addition, the lifespan of the wireless sensor network is limited and short. Therefore, reducing the energy consumption of sensors in IoT networks for increasing network lifespan is one of the fundamental challenges and issues in these networks. In this paper, a routing protocol is proposed and simulated based on an ant colony optimization algorithm's performance. The clustering is performed with a routing method based on energy level criteria, collision reduction, distance from the cluster-head to the destination, and neighborhood energy in the proposed method. The cluster head is selected based on the maximum residual energy, minimum distance with other clusters, and consumed energy. This energy is minimized to reach the base station. The node with more energy than the threshold is selected as the new cluster head. Then, four conditions are applied for routing: the shortest path, the leading path, the shortest distance to the source node and the destination node, and routing. Results show that after about 50 cycles of transferring information, only the average of 19.4% of the initial energy is consumed in the network nodes. Therefore, obtained results illustrate that the proposed method helps to retain the energy more than 40% comparing the available methods. [ABSTRACT FROM AUTHOR]

• Carbohydrates in the basal stems were continuously degraded as the major storage energy for shoot elongation in vitro. • The shoot tips exhibited greater capacity for ROS scavenging compared with the basal stems. • Comparative proteomics revealed the different metabolism patterns in the basal stems and the shoot tips. Dodder is a holoparasitic flowering plant that re-establishes parasitism with the host when broken off from the host. However, how in vitro dodder shoots recycle stored nutrients to maintain growth for reparasitizing hosts is not well characterized. Here, the spatial and temporal distribution characteristics of carbohydrates and reactive oxygen species (ROS) were analysed to explore the mechanism of recycling stored nutrients in dodder shoots in vitro. Our results showed that in vitro dodder shoots grew actively for more than 10 d, while dry mass decreased continuously. During this process, the transcript levels and activities of amylases gradually increased until 2 d and then declined in basal stems, which induced starch degradation at the tissue, cellular and subcellular levels. Additionally, the distribution characteristics of H 2 O 2 and the activities and transcript levels of antioxidant enzymes indicated that shoot tips exhibited more robust ROS-scavenging capacity, and basal stems maintained higher ROS accumulation. Comparative proteomics analysis revealed that starch in basal stems acted as an energy source, and the glycolysis, TCA cycle and pentose phosphate pathway represented the energy supply for shoot tip elongation with time. These results indicated that efficient nutrient recycling and ROS modulation facilitated the parasitism of dodder grown in vitro by promoting shoot elongation growth to reach the host. [ABSTRACT FROM AUTHOR]

Di-(2-ethylhexyl) phthalate (DEHP), which is widely used as an industrial plasticizer, may cause liver damage. Concomitantly, bad dietary habits can exacerbate the liver burden. In this study, high-fat diet (HFD)-fed rats were treated with DEHP (10, 100, or 300 mg/kg bw) for 5 weeks, and a biochemical method was adopted to detect serum lipid contents. Key metabolic genes and pathological changes were assessed by different methods (RT-PCR, Western Bloting, ELISA and HE staining). The rats which were exposed to DEHP at a dose of 10 mg/kg bw exhibited dyslipidemia and increased transcription of SREBP-1 and its target FAS, thereby prompting de novo lipogenesis, but they did not become obese. Instead, DEHP at a dose of 300 mg/kg bw elevated the levels of AMPK phosphorylation and the mRNA levels of PPAR-α, PGC-1α, CPT-1 and lipin-1 in the liver, which led to fatty acid oxidation. Additionally, DEHP at the highest dose increased the TNF-α mRNA expression in the liver. Based on these findings, we conclude that excess fatty acid oxidation might increase the inflammatory response. No toxic effects on hepatic function were observed. These findings suggest that different doses of DEHP have the potential to disturb hepatic metabolic imbalance in HFD-fed rats. Image 1 • The HFD-fed rats exposed to DEHP did not show increased body weight, whereas worse metabolic profile. • Different doses of DEHP disrupt lipid metabolic profiles. • DEHP at the lowest dose prompts de novo lipogenesis. • DEHP at the highest dose improve fatty acid oxidation. [ABSTRACT FROM AUTHOR]

Activation of nitromethane to endow new reactivity is an interesting and meaningful but also challenging topic. Herein, we report an electrochemical activation of nitromethane to serve as both the heterocyclic skeleton and oxime sources for the construction of isoxazoline aldoximes. The isoxazoline aldoximes that are prepared by four steps with the reported strategy are synthesized in a single step from low‐cost and readily available nitromethane and olefins with moderate to excellent yields under our electrochemical conditions. The reaction also takes advantage of high atom‐economy and E‐selectivity. Moreover, the mechanism is studied by control experiments, a kinetic isotope effect (KIE) study, cyclic voltammogram (CV) experiments, and density functional theory (DFT) calculations. The mechanistic results reveal that nitromethane may be activated under electrochemical conditions to deliver a 1,2,5‐oxadiazole 2‐oxide intermediate, which undergoes [3+2] cycloaddition with olefins to yield isoxazoline aldoximes. [ABSTRACT FROM AUTHOR]

Activation of nitromethane to endow new reactivity is an interesting and meaningful but also challenging topic. Herein, we report an electrochemical activation of nitromethane to serve as both the heterocyclic skeleton and oxime sources for the construction of isoxazoline aldoximes. The isoxazoline aldoximes that are prepared by four steps with the reported strategy are synthesized in a single step from low‐cost and readily available nitromethane and olefins with moderate to excellent yields under our electrochemical conditions. The reaction also takes advantage of high atom‐economy and E‐selectivity. Moreover, the mechanism is studied by control experiments, a kinetic isotope effect (KIE) study, cyclic voltammogram (CV) experiments, and density functional theory (DFT) calculations. The mechanistic results reveal that nitromethane may be activated under electrochemical conditions to deliver a 1,2,5‐oxadiazole 2‐oxide intermediate, which undergoes [3+2] cycloaddition with olefins to yield isoxazoline aldoximes. [ABSTRACT FROM AUTHOR]

This method allows the synthesis of β-hydroxyesters from simple enals with excellent enantioselectivities and in good yields. [ABSTRACT FROM AUTHOR]

Taiyuan is a center of coal-based electricity production and many chemicals industries, where mixtures of sulfur dioxide (SO2) and particulate matter may be more prominent. The focus of the present study was to determine if there is a link between adverse effects in the brain and the combined-exposure to SO2and fine particulate matter (PM2.5). Rats were exposed alternately to PM2.5with different dosages (1.5, 6.0 and 24.0 mg/kg body weight) and SO2at the level of 5.6 mg/m3. The results showed that the combined exposure to PM2.5and SO2enhanced the mRNA expression and protein level of TNF-α and IL-6 in rat cortex and hippocampus relative to the control, SO2and PM2.5alone. Instead, TGF-β1 mRNA and protein level were down-regulated in the brain. Additionally, PM2.5at medium and/or high dose caused marked increase in Aβ42 level and PM2.5 + SO2induced further increase of Aβ42 level in the cortex and hippocampus. It suggests that SO2and PM2.5can synergistically exert inflammation responses and induce Aβ42 accumulation in the brain. Also, it is notable that the Aβ42 accumulation of rat cortex and hippocampus were closely associated with pro-/anti-inflammatory cytokines ratio. These results clearly demonstrated that the combined exposure to PM2.5and SO2can induce the imbalance of pro-/anti-inflammatory cytokine, resulting in Aβ42 accumulation of rat brain cortex and hippocampus. [ABSTRACT FROM AUTHOR]

A carbene-catalyzed intermolecular C−N bond formation, which initiates a highly selective cascade reaction for the synthesis of pyrrolidine fused β-lactones, is disclosed. The nitrogen-containing bicyclic β-lactone products are obtained with good yields and excellent stereoselectivities. Synthetic transformations of the reaction products into useful functional molecules, such as amino catalysts, can be efficiently realized under mild reaction conditions. Mechanistically, this study provides insights into modulating the reactivities of heteroatoms, such as nitrogen atoms, in challenging carbene-catalyzed asymmetric carbon-heteroatom bond-forming reactions. [ABSTRACT FROM AUTHOR]

A carbene-catalyzed intermolecular C−N bond formation, which initiates a highly selective cascade reaction for the synthesis of pyrrolidine fused β-lactones, is disclosed. The nitrogen-containing bicyclic β-lactone products are obtained with good yields and excellent stereoselectivities. Synthetic transformations of the reaction products into useful functional molecules, such as amino catalysts, can be efficiently realized under mild reaction conditions. Mechanistically, this study provides insights into modulating the reactivities of heteroatoms, such as nitrogen atoms, in challenging carbene-catalyzed asymmetric carbon-heteroatom bond-forming reactions. [ABSTRACT FROM AUTHOR]

An enantioselective β-carbon amination for enals is disclosed. The nitrogen atom from a protected hydrazine with suitable electronic properties readily behaves as a nucleophile. Addition of the nitrogen nucleophile to a catalytically generated N-heterocyclic-carbene-bound α,β-unsaturated acyl azolium intermediate constructs a new carbon-nitrogen bond asymmetrically. The pyrazolidinone products from our catalytic reactions are common scaffolds in bioactive molecules, and can be easily transformed into useful compounds such as β3-amino-acid derivatives. [ABSTRACT FROM AUTHOR]

An enantioselective β-carbon amination for enals is disclosed. The nitrogen atom from a protected hydrazine with suitable electronic properties readily behaves as a nucleophile. Addition of the nitrogen nucleophile to a catalytically generated N-heterocyclic-carbene-bound α,β-unsaturated acyl azolium intermediate constructs a new carbon-nitrogen bond asymmetrically. The pyrazolidinone products from our catalytic reactions are common scaffolds in bioactive molecules, and can be easily transformed into useful compounds such as β3-amino-acid derivatives. [ABSTRACT FROM AUTHOR]

It is well known that ordinary filling materials have some difficulties in roof contact. As a result, this paper proposed a novel method that addition of a foaming agent into filling slurry led to foaming expansion of the filling slurry through chemical reaction, thus achieving roof contact. The filling material was prepared by mix ordinary portland cement, mine tailings and hydrogen peroxide in a certain ratio. Its basic physical properties, structure, slump, swelling and mechanical properties were characterised. The results show that the slump of the filling slurry increases with concentration decreasing. At 67 - 73% solid concentration, the slurry flow ability is best. The presence of a small amount of hydrogen peroxide can effectively prevent the slurry settlement and increase bleeding. The slurry expansion rate is positively correlated with addition amount of hydrogen peroxide. In the absence of hydrogen peroxide, the slurry bleeding rate gradually decreases with concentration increasing. However, the residual water in the filling body due to the existence of porosity lowers its strength. Therefore, the content of the cement- sand in a predetermined ratio is desired to be as high as practical to enhance the slurry strength. [ABSTRACT FROM AUTHOR]

An NHC-catalyzed activation of acetic esters to afford enolate intermediates is disclosed. The catalytically generated triazolium enolate intermediates serve as two-carbon nucleophiles that undergo highly enantioselective reactions with enones and α,β-unsaturated imines to give α-unsubstituted δ-lactones and lactams, respectively. [ABSTRACT FROM AUTHOR]

A novel treatment of carbon fiber (CF) with Fenton reagent was used to improve its surface properties, immobilization efficiency (IE), and xylitol yield. The process realized the oxidized treatment and the introduction of iron ions on CF. The specific surface area, surface acidity and degree of moisture increased, while the contact angle and the pH of the point of zero charges decreased after the treatment by Fenton reagent. Notably, the high-affinity iron ions introduced by the modification that enhanced the intracellular coenzyme cycle for xylitol accumulation due to the higher NADPH/NADP+ ratio and NADPH content. In addition, introduced iron ion on the CF promoted the reduction of intracellular reactive oxygen species level and mitochondrial membrane polarization level. As a result, compared to the untreated-CF, the IE and xylitol yield were increased by 86.15 % and 43 % with the treated CF, respectively. Using Fenton reagent to treat CF provided an excellent method to prepare biocompatible immobilized carriers for industrial production of xylitol. [Display omitted] • Solve the defects of carbon fiber such as chemical inertia and poor hydrophilicity. • A new application of Fenton reagent for modified carbon fiber has been developed. • The immobilization efficiency of the optimized carbon fiber increased by 86.15 %. • The cell viability of the optimized carbon fiber was 1.51 times that of the original. • This is a promising method for preparing biocompatible vectors. [ABSTRACT FROM AUTHOR]

An efficient and convenient protocol for synthesis of dichlorocyanomethyl‐functionalized oxindoles through the cascade reactions of dichlorocyanomethyl radical with N‐arylacrylamides is reported. The electrophilic dichlorocyanomethyl radical, which is generated from readily available trichloroacetonitrile via a copper‐catalyzed single‐electron transfer (SET) process, undergoes radical addition with the electron‐deficient C=C bonds of N‐arylacrylamides, followed by intramolecular cyclization, to provide dichlorocyanomethyl‐functionalized oxindoles. No external oxidant is needed in this transformation. [ABSTRACT FROM AUTHOR]

Recently-emerged base editing technologies could create single base mutations at precise genomic positions without generation DNA double strand breaks. Herbicide resistant mutations have been successfully introduced to different plant species, including Arabidopsis, watermelon, wheat, potato and tomato via C to T (or G to A on the complementary strand) base editors (CBE) at the P197 position of endogenous acetolactate synthase (ALS) genes. Additionally, G to A conversion to another conserved amino acid S653 on ALS gene could confer tolerance to imidazolinone herbicides. However, no such mutation was successfully generated via CBE, likely due to the target C base is outside of the classic base editing window. Since CBE driven by egg cell (EC) specific promoter would re-edit the wild type alleles in egg cells and early embryos, we hypothesized the diversity of base editing outcomes could be largely increased at later generations to allow selection of desired herbicide resistant mutants. To test this hypothesis, we aimed to introduce C to T conversion to the complement strand of S653 codon at ALS gene, hosting a C at the 10th position within the 20-nt spacer sequence outside of the classic base editing window. While we did not detect base-edited T1 plants, efficient and diverse base edits emerged at later generations. Herbicide resistant mutants with different editing outcomes were recovered when T3 and T4 seeds were subject to herbicide selection. As expected, most herbicide resistant plants contained S653N mutation as a result of G10 to A10. Our results showed that CBE could create imidazolinone herbicide resistant trait in Arabidopsis and be potentially applied to crops to facilitate weed control. [ABSTRACT FROM AUTHOR]

Aim. To evaluate the eradication rate, safety, and compliance of minocycline-containing bismuth quadruple regimens in patients with an untreated Helicobacter pylori (H. pylori) infection. Methods. A total of 360 patients with an untreated H. pylori infection were enrolled in this study between June 2017 and October 2018. Patients were randomly divided into a minocycline/amoxicillin (RMAB) group, a minocycline/metronidazole (RMMB) group, or an amoxicillin/clarithromycin (RACB) group, and all groups received a combined treatment approach with rabeprazole and bismuth to create a quadruple regimen for 14 days. A 3 to 5-day follow-up was adopted to evaluate the safety and compliance of medications after medicine administration. 13C-urea breath test was performed to confirm the eradication of H. pylori 4-12 weeks after therapy. Results. No significant differences were observed at baseline data among the three groups (p > 0.05). Based on the intent-to-treat analysis, the eradication rates of the RMAB group, RMMB group, and RACB control group were 85.7% (102/119), 77.1% (91/118), and 71.7% (86/120), respectively, with significant difference ( χ 2 = 7.015 , p = 0.030). According to per protocol analysis, the eradication rates of RMAB group, RMMB group, and RACB group were 89.5% (102/114), 84.3% (91/108), and 76.8% (86/112), respectively, with statistically significant differences ( χ 2 = 6.673 , p = 0.036). The eradication rates of the RMAB group and RACB group were significantly different (p < 0.05). The overall incidences of adverse events in the three groups were 30.0%, 37.5%, and 40.0%, respectively (p > 0.05). Nausea, epigastric discomfort, and dizziness were more obvious in patients in the RMMB group compared to the other two groups (p < 0.05). Moreover, two patients discontinued due to severe dizziness and nausea in the RMMB group. A taste disorder was more prominent in patients in the RACB group compared to patients in the other two groups (p < 0.05), and one patient discontinued because of the bitterness in the mouth. Soon after discontinuation of the medicine, all adverse events disappeared. Conclusion. The bismuth quadruple regimen using minocycline/amoxicillin showed a better eradication effect with fewer side effects in patients with untreated H. pylori infections. The bismuth quadruple regimen with minocycline/metronidazole had a good eradication effect with more obvious side effects and might be recommended to patients with penicillin allergy. [ABSTRACT FROM AUTHOR]

A novel biosensor was fabricated based on the immobilization of tyrosinase and N-acetyl- L-cysteine-capped gold nanoparticles onto the surface of the glassy carbon electrode via the film forming by chitosan. The NAC-AuNPs ( N-acetyl- L-cysteine-capped gold nanoparticles) with the average size of 3.4 nm had much higher specific surface area and good biocompatibility, which were favorable for increasing the immobilization amount of enzyme, retaining the catalytic activity of enzyme and facilitating the fast electron transfer. The prepared biosensor exhibited suitable amperometric responses at −0.2 V for phenolic compounds vs. saturated calomel electrode. The parameters of influencing on the working electrode such as pH, temperature, working potential were investigated. Under optimum conditions, the biosensor was applied to detect catechol with a linear range of 1.0 × 10−7 to 6.0 × 10−5 mol•L−1 , and the detection limit of 5.0 × 10−8 mol•L−1 ( S/ N=3). The stability and selectivity of the proposed biosensor were also evaluated. [ABSTRACT FROM AUTHOR]

[Display omitted] We develop an efficient and workable method for the reduction of imines via hydroboration with HBpin. The low cost and non-toxic Fe exhibits high catalytic activity to this hydroboration. A large range of aldimines comprising diverse aryl groups, alkyl groups and heterocycles proceed the hydroboration well to yield secondary amines in good to excellent yields. Kinetic mechanistic studies indicate the importance of Fe in transformation of HBpin into an active species. The preparation of several commercially available pharmaceuticals by means of this strategy highlights its potential application in medicinal chemistry. [ABSTRACT FROM AUTHOR]

An N-heterocyclic carbene-catalyzed activation of acetic esters to afford enolate intermediates is disclosed. [ABSTRACT FROM AUTHOR]

• The influence of adoption threshold heterogeneity on the process of information dissemination is studied in a two-layer network. • The propagation model with limited contact is established. • The threshold of information adoption is affected by the degree of node and a parameter obeying truncated normal distribution. • Increasing the mean of parameters can inhibit information spreading and the effect of standard deviation of parameters on information dissemination depends on the mean of parameters. The spreading process of information on complex networks has been widely explored. In fact, different individuals in a network usually hold different standards for information adoption. Considering the heterogeneity of adoption thresholds, this study constructs a two-layer network model with limited contacts. The adoption threshold of a node is related to its degree and a parameter obeying truncated normal distribution. This study also proposes a partition theory based on edges to analyze the mechanism of information dissemination quantitatively. Experiments find that increasing the mean of parameters can inhibit information from spreading, and the effect of the standard deviation of parameters on information dissemination depends on the mean of parameters. For instance, when the mean of parameters is a low value, as the standard deviation of parameters increases, the information outbreak size will decrease. On the other hand, the information outbreak size will increase continuously with increased propagation probability. If the mean of parameters is high, the information outbreak size will increase first and then decrease with the increment in the standard deviation of parameters. The theoretical predictions of this study are in good agreement with the numerical simulations. [ABSTRACT FROM AUTHOR]

REFERENCES 1 Zhang L., Yu L., Wang Q., Zhang Y., Si X. Application of Minocycline-Containing Bismuth Quadruple Therapies as First-Line Regimens in the Treatment of Helicobacter pylori. In the article titled "Application of Minocycline-Containing Bismuth Quadruple Therapies as First-Line Regimens in the Treatment of Helicobacter pylori" [[1]], there was an error in Subjects and Methods. [Extracted from the article]

Modified gibberellin (GA) signaling leads to semi-dwarfism with low nitrogen (N) use efficiency (NUE) in crops. An understanding of GA-mediated N uptake is essential for the development of crops with improved NUE. The function of GA in modulating N uptake capacity and nitrate (NO3−) transporters (NRTs) was analyzed in the GA synthesis-deficient mutant zmga3ox grown under low (LN) and sufficient (SN) N conditions. LN significantly suppressed the production of GA1, GA3, and GA4, and the zmga3ox plants showed more sensitivity in shoots as well as LN stress. Moreover, the higher anthocyanin accumulation and the decrease of chlorophyll content were also recorded. The net NO3− fluxes and 15N content were decreased in zmga3ox plants under both LN and SN conditions. Exogenous GA3 could restore the NO3− uptake in zmga3ox plants, but uniconazole repressed NO3− uptake. Moreover, the transcript levels of ZmNRT2.1/2.2 were downregulated in zmga3ox plants, while the GA3 application enhanced the expression level. Furthermore, the RNA-seq analyses identified several transcription factors that are involved in the GA-mediated transcriptional operation of NRTs related genes. These findings revealed that GAs influenced N uptake involved in the transcriptional regulation of NRTs and physiological responses in maize responding to nitrogen supply. [ABSTRACT FROM AUTHOR]

Recently, the demand for human activity recognition has become more and more urgent. It is widely used in indoor positioning, medical monitoring, safe driving, etc. Existing activity recognition approaches require either the location information of the sensors or the specific domain knowledge, which are expensive, intrusive, and inconvenient for pervasive implementation. In this paper, a human activity recognition algorithm based on SDAE (Stacking Denoising Autoencoder) and LightGBM (LGB) is proposed. The SDAE is adopted to sanitize the noise in raw sensor data and extract the most effective characteristic expression with unsupervised learning. The LGB reveals the inherent feature dependencies among categories for accurate human activity recognition. Extensive experiments are conducted on four datasets of distinct sensor combinations collected by different devices in three typical application scenarios, which are human moving modes, current static, and dynamic behaviors of users. The experimental results demonstrate that our proposed algorithm achieves an average accuracy of 95.99%, outperforming other comparative algorithms using XGBoost, CNN (Convolutional Neural Network), CNN + Statistical features, or single SDAE. [ABSTRACT FROM AUTHOR]

With the booming development of green lighting technology, visible light-based indoor localization has attracted a lot of attention. Visible light-based indoor positioning technology leverages a light propagation model to pinpoint target location. Compared with the radio localization technology, visible light-based indoor positioning not only can achieve higher location accuracy, but also no electromagnetic interference. In this article, we propose LIPOS, a three-dimensional indoor positioning system based on attitude identification and visible light propagation model. The LIPOS system takes advantage of the existing lighting infrastructures to localize mobile devices that have light-sensing capabilities (e.g. a smartphone) using light emitting diode lamps as anchors. The system can accurately identify the attitude of a smartphone using its integrated sensors, distinguish different light emitting diode beacons using the fast Fourier transform algorithm, construct a position cost-function based on a visible light radiative decay model, and apply a nonlinear optimizing method to acquire the optimal estimation of final location. We have implemented the LIPOS system and evaluated it with a small-scale hardware testbed, as well as moderate-sized simulations. Extensive experiments are performed in three representative indoor environments—open-plan office, cubicle, and corridor, which not only demonstrate that the LIPOS can effectively avoid the negative effects of dynamic change of a smartphone’s attitude angle, but also show better locating accuracy and robustness, and obtain sub-meter level positioning accuracy. [ABSTRACT FROM AUTHOR]