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Single neuron control system not only has simple structure and strong robustness, but also can adapt to the systems affected by interference. At the same time, Smith predictor is characterized by predicting the dynamic characteristics of time-delay systems. Aimed at the problem of time delay in networked control systems, a kind of controller based on improved single neuron adaptive PID with new Smith predictor is presented. It utilizes the self-learning and self-adaptive ability of single neuron, and Smith predictive compensation characteristics. The network based control for a DC motor is simulated in Matlab. The simulation result shows that the control algorithm based on improved Single Neuron adaptive PID with new Smith predictor can effectively improve the robustness and adaptability of networked control systems. [ABSTRACT FROM AUTHOR]

Objectives: The saline suppression test (SST) serves to confirm the diagnosis of primary aldosteronism (PA), while adrenal vein sampling (AVS) is used to subtype PA as unilateral or bilateral. Criteria that can accurately identify those with bilateral PA based on SST results could reduce the need for AVS. We previously demonstrated that a combination of plasma aldosterone concentration (PAC)<300 pmol L-1 and a reduction in aldosterone-to-renin ratio (ARR) following recumbent SST had high specificity for predicting bilateral PA in an Australian cohort of 92 patients with PA who have undergone AVS. We sought to validate our predictive criteria in larger, independent cohorts of patients with PA. Design: An international, multi-centre cohort study. Methods: Data from 55 patients at Monash Health, Victoria, Australia, 106 patients from the First Affiliated Hospital of Chongqing Medical University, China, and 105 patients from Nihon University Itabashi Hospital, Japan were analysed. Results: A combination of PAC <300 pmol L-1 and a reduction in ARR following recumbent SST predicted bilateral PA with specificities of 88.2%, 97.0%, and 100.0% in Australian, Chinese, and Japanese cohorts, respectively. This criterion could allow 22%-38% of patients with PA to bypass AVS and proceed directly to medical treatment. Conclusion: In patients undergoing the recumbent SST, a post-saline PAC <300 pmol L-1 together with a reduction in ARR can predict bilateral PA with high specificity and may allow targeted treatment to be commenced without AVS in up to a third of patients. [ABSTRACT FROM AUTHOR]

Summary: Shade affects all aspects of plant growth and development, including seed germination, hypocotyl elongation, petiole growth, leaf hyponasty, and flowering time. Here, we found that mutations in the key Arabidopsis karrikins signal perception‐associated KARRIKIN INSENSITIVE 2 (KAI2) gene, encoding an α/β‐fold hydrolase, and the MORE AXILLARY GROWTH 2 (MAX2) gene, encoding an F‐box protein, led to greater hypocotyl elongation under shade avoidance conditions.We further verified that these phenotypes were caused by perception of the endogenous KAI2‐ligands (KLs), and that this phenotype is independent of strigolactone biosynthetic or signaling pathways. Upon perception of a KL, it is probable that the target protein forms a complex with the KAI2/MAX2 proteins, which are degraded through the action of the 26S proteasome.We demonstrated that SUPPRESSOR OF MAX2‐1 (SMAX1) is the degradation target for the KAI2/MAX2 complex in the context of shade avoidance. KAI2 and MAX2 require SMAX1 to limit the hypocotyl growth associated with shade avoidance. Treatment with l‐kynurenine, an inhibitor of auxin accumulation, partially restored elongation of kai2 mutant hypocotyls under simulated shade. Furthermore, KAI2 is involved in regulating auxin accumulation and polar auxin transport, which may contribute to the hypocotyl shade response.In addition, SMAX1 gene overexpression promoted the hypocotyl shade response. RNA‐sequencing analysis revealed that SMAX1‐overexpression affected the expression of many auxin homeostasis genes, especially under simulated shade. Altogether, our data support the conclusion that KL signaling regulates shade avoidance by modulating auxin homeostasis in the hypocotyl. [ABSTRACT FROM AUTHOR]

Background/Aims: Whether angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARB) could benefit patients with diabetes and albuminuria remains controversial. A systematic review and meta-analysis were conducted to answer this question by comparing ACE inhibitors or ARB with placebo among these patients. Methods: In this meta-analysis, electronic data sources (Medline, the Cochrane Collaboration, and EMBASE) were searched. Randomized controlled trials (RCTs) comparing ACE inhibitors or ARB with placebo in subjects with diabetes and albuminuria (defined as urinary albumin-to-creatinine ratio, UACR≥30mg/g Cr) were included. Outcomes parameters were all-cause mortality, end stage renal disease (ESRD), doubling of serum creatinine levels, and cardiovascular events (CV). Results: Twenty-six RCTs (including 20 for ACE inhibitors and 6 for ARB) were included, comprising 10378 participants with diabetes and albuminuria. Compared to placebo, treatment with ACE inhibitors or ARBs did not reduce all-cause mortality or CV. For renal outcomes, ARBs significantly reduced the risk of ESRD by 23% (odds ratio 0.77, 95%CI 0.65-0.92), while ACE inhibitors were not associated with a decreased risk of ESRD (0.69, 0.43-1.10). Both ACE inhibitors and ARBs reduced the risk of doubling of the serum creatinine level (0.60, 0.39-0.91 for ACE inhibitors; 0.75, 0.64-0.88 for ARBs), and subgroup analyses for patients with macroalbuminuria or microalbuminuria showed similar results. Conclusion: In patients with diabetes and albuminuria, ARBs reduced risks of ESRD and doubling of the serum creatinine level. ACE inhibitors and ARBs failed to reduce all-cause mortality and CV. Based on the renoprotective effects, ARBs may be preferred for diabetic patients with albuminuria. [ABSTRACT FROM AUTHOR]

The prevalence of hyperuricemia has increased rapidly over the past decades. Bisphenol A (BPA) is an environmental endocrine disruptor. We investigated the effects of BPA on uric acid metabolism and its potential mechanisms. Experiments were performed in different animal models, cell cultures, and humans. In 3 different animal models, BPA exposure increased serum and hepatic uric acid with enhanced activity of xanthine oxidase (XO) in liver, whereas the excretion of uric acid was unchanged. Both in vivo and in vitro, BPA-induced uric acid production was decreased after treatment with allopurinol, which is a XO inhibitor. XO led to the accumulation of uric acid after xanthine was added, with the enzyme-catalyzed reaction, which was enhanced by BPA. Altered secondary structures of XO were found by circular dichroism analysis in the conditions of different BPA concentrations. Molecular docking portrayed Asp360 and Lys422 of XO to be the preferred binding sites for BPA. Mutation of both sites significantly blocked the effect of BPA on XO activity. In humans, patients with hyperuricemia exhibited higher levels of serum BPA than subjects without hyperuricemia. These findings demonstrate BPA promotes hyperuricemia by increasing hepatic uric acid synthesis via the activation of XO, probably through direct binding. [ABSTRACT FROM AUTHOR]

Multi-functionalized fluorinated arenes, especially those that are transformable fluorinated building blocks, are intriguing compounds in synthetic chemistry and for life science related applications. The development of straightforward and efficient approaches to these compounds is of significant importance and has, therefore, attracted much attention. This short review presents our recent progress on the fluoro-difunctionalization of arynes, which allows facile construction of a series of fluorinated arene building blocks bearing an ortho-iodine substituent as a coupling handle for further elaboration. 1 Introduction 2 Silver-Mediated Trifluoromethylation-Iodination of Arynes 3 Silver-Catalyzed Insertion of Aryne into Rf-I Bonds 4 Diphenyliodonium-Catalyzed Fluorination of Arynes 5 Silver-Mediated Trifluoromethylthiolation-Iodination of Arynes 6 Summary and Outlook [ABSTRACT FROM AUTHOR]

A one-pot trifluoromethylthiolation-iodination of arynes with trifluoromethylthiosilver (AgSCF3) and 1-iodophenylacetylene is described. This protocol allows rapid construction of o-trifluoromethylthiolated arene building blocks in moderate yields. These products were found to be excellent precursors for Yagupolskii-Umemoto-type electrophilic trifluoromethylation reagents. [ABSTRACT FROM AUTHOR]

A one-pot trifluoromethylthiolation-iodination of arynes with trifluoromethylthiosilver (AgSCF3) and 1-iodophenylacetylene is described. This protocol allows rapid construction of o-trifluoromethylthiolated arene building blocks in moderate yields. These products were found to be excellent precursors for Yagupolskii-Umemoto-type electrophilic trifluoromethylation reagents. [ABSTRACT FROM AUTHOR]

Reference electrodes are used in almost every electroanalytical measurement. Here, all-solid-state reference electrodes are described that employ colloid-imprinted mesoporous (CIM) carbon as solid contact and a poly(vinyl chloride) reference membrane to contact the sample. Such a reference membrane is doped with a moderately hydrophilic ionic liquid and a hydrophobic redox couple, leading to welldefined constant potentials at the interfaces of this membrane to the sample and to the solid contact, respectively. Due to the intrinsic properties o f CIM carbon, reference electrodes with a CIM carbon solid contact exhibit excellent resistance to common interfering agents such as light and O2, with outstanding potential stability in continuous potentiometric measurements. The potential drift of CIM carbon-based reference electrodes without redox couple is as low as 1.7 μV /h over 110 h, making them the most stable all-solid-state reference electrodes reported so far. To demonstrate the compatibility o f CIM carbon-based reference electrodes with miniaturized potentiometric systems, these reference electrodes were integrated into paper-based potentiometric sensing devices, successfully replacing the conventional reference electrode with its reference electrolyte solution. As a proof of concept, disposable paper-based Cl- sensing devices that contain stencil-printed Ag/AgClbased Cl- selective electrodes and CIM carbon-based reference electrodes were constructed. These sensing devices are inexpensive, easy to use, and offer highly reproducible Cl- measurements with sample volumes as low as 10 μL. [ABSTRACT FROM AUTHOR]

A new type of solid-contact ion-selective electrode (SC-ISE) has been developed that uses colloidimprinted mesoporous (CIM) carbon with 24 nm diameter, interconnected mesopores as the intermediate layer between a gold electrode and an ionophore-doped ISE membrane. For a demonstration, valinomycin was used as K+ ionophore, and a good Nemstian response with a slope of 59.5 mV/decade in the range from 10-52 to 10-10 M was observed. The high purity, low content of redox-active surface functional groups and intrinsic hydrophobic characteristics of CIM carbon prepared from mesophase pitch lead to outstanding performance of these sensors, with excellent resistance to the formation of a water layer and no interference caused by light, O2, and CO2. When a redox couple is introduced as an internal reference species, calibration-free SC-ISEs can be made with a standard deviation of EL as low as 0.7 mV. Moreover, the interconnected mesopore structure of ISE membrane-infused CIM carbon facilitates both ion and electron conduction and provides a large interfacial area with good ion-to-electron transduction. Because of the large double layer capacitance of CIM carbon, CIM carbon-based SC-ISEs exhibit excellent potential stability, as shown by chronopotentiometry and continuous potentiometric measurements. The capacitance of these electrodes as determined by chronopotentiometry is 1.0 mF, and the emf drift over 70 h is as low as 1.3 pV / h, making these electrodes the most stable SC-ISEs reported so far. [ABSTRACT FROM AUTHOR]

Difluorocarbene is a versatile, reactive intermediate for use in organic synthesis. Over the past decade, significant progress has been made in difluorocarbene chemistry owing to the increasing demand for various fluorinated molecules. Not only the substrate scope for some classical difluorocarbene reagents has been largely expanded, but also new and environmentally friendly difluorocarbene reagents for difluoromethylation and gem-difluorocyclization have been developed. This review summarizes the difluoromethylation, gem-difluorocyclopropanation, gem-difluorocyclopropenation, gem-difluoroolefination, and trifluoromethylation achieved in the last decade using both the classical and the new difluorocarbene sources. 1 Introduction 2 Difluorocarbene Sources 3 Difluoromethylation 3.1 O-Difluoromethylation 3.2 S-Difluoromethylation 3.3 N-Difluoromethylation 3.4 Difluoromethylation of Ambident N,O- and N,S-Nucleophiles 3.5 Se- and P-Difluoromethylation 3.6 C-Difluoromethylation 3.7 Sn-Difluoromethylation 4 gem-Difluorocyclization 4.1 gem-Difluorocyclopropanation 4.2 gem-Difluorocyclopropenation 5 gem-Difluoroolefination and Related Reactions 6 Trifluoromethylation 7 Miscellaneous 8 Conclusions [ABSTRACT FROM AUTHOR]

Selective incorporation of fluorine atoms or fluorinecontaining moieties into organic molecules has become a routine and powerful strategy in drug design and new functional-material development. Nucleophilic fluoroalkylation, typically involving the transfer of a fluorinated carbanion or carbanion equivalent to an electrophile, is one of the most important and frequently used methods to synthesize fluorinated organic molecules. In this Account, we introduce some recent achievements in the field of nucleophilic diand monofluoroalkylation chemistry with functionalized fluoroalkylation reagents. In particular, the effect of fluorine substitution on the reactivity of carbanions is discussed, and several strategies for improving nucleophilic fluoroalkylations are proposed and successfully applied in various new nucleophilic fluoroalkylation reactions. It was found that attaching a removable activation group (such as the phenylsulfonyl group) to a fluorinated carbanion is an important approach to improve the latter's reactivity. [ABSTRACT FROM AUTHOR]

The selective introduction of fluorine atom(s) and fluorinated moieties into organic molecules has become an important and fast-growing research field, since fluorine atoms play crucial roles in life science and materials science-related applications. Similar to the trifluoromethyl group, both difluoromethyl and monofluoromethyl groups can often bring about many beneficial effects to the target molecules, and a variety of CF2H- and CH2F-containing pharmaceuticals and agrochemicals have been developed. Among the synthetic methods for CF2H- and CH2F-containing compounds, selective di- and monofluoromethylation (i.e., introduction of CF2H and CH2F groups into organic molecules) represent one of the most straightforward synthetic methods and thus can be conveniently used in the synthetic design. This feature article summarizes the presently known selective difluoromethylation and monofluoromethylation methods, including nucleophilic, electrophilic, and free radical di- and monofluoromethylation reagents and reactions. [ABSTRACT FROM AUTHOR]

Selective incorporation of a fluoroalkyl moiety to modulate the properties of an organic molecule has become a frequently used strategy in life science- and materials science-related applications. In this context, selective introduction of a (phenylsulfonyl)difluoromethyl group (PhSO2CF2) into organic molecules has attracted much attention, since the PhSO2CF2 group can be regarded as a “chemical chameleon” that can be readily transformed into difluoromethyl (CF2H), difluoromethylene (–CF2–), and difluoromethylidene (=CF2) functionalities. This article overviews the recent development of (phenylsulfonyl)difluoromethylation reactions from 2003, including the nucleophilic (phenylsulfonyl)difluoromethylations with PhSO2CF2H, PhSO2CF2SiMe3 and PhSO2CF2Br reagents, free radical (phenylsulfonyl)difluoromethylations with PhSO2CF2I reagent, and electrophilic (phenylsulfonyl)difluoromethylations with a hypervalent iodine(III)-CF2SO2Ph reagent. [Copyright &y& Elsevier]

The selective introduction of fluorine atom(s) and fluorinated moieties into organic molecules has become an important and fast-growing research field, since fluorine atoms play crucial roles in life science and materials science-related applications. Similar to the trifluoromethyl group, both difluoromethyl and monofluoromethyl groups can often bring about many beneficial effects to the target molecules, and a variety of CF2H- and CH2F-containing pharmaceuticals and agrochemicals have been developed. Among the synthetic methods for CF2H- and CH2F-containing compounds, selective di- and monofluoromethylation (i.e., introduction of CF2H and CH2F groups into organic molecules) represent one of the most straightforward synthetic methods and thus can be conveniently used in the synthetic design. This feature article summarizes the presently known selective difluoromethylation and monofluoromethylation methods, including nucleophilic, electrophilic, and free radical di- and monofluoromethylation reagents and reactions. [ABSTRACT FROM AUTHOR]

Efficient fluoroalkylations have been proven to be a highly useful strategy for the synthesis of bioactive fluorine-containing compounds and other materials. The design and use of a single category of reagents for multiple synthetic goals are much more attractive to preparative organic chemists. In this Account, we show how we have succeeded in the nucleophilic trifluoromethylation, difluoromethylation, difluoromethylenation, (phenylsulfonyl)difluoromethylation, (phenylthio)difluoromethylation, and monofluoromethylation as well as radical (phenylsulfonyl)difluoromethylation and electrophilic difluoromethylation by using fluorinated sulfones, sulfoxides, sulfides, or fluorinated sulfonium salts. The chemistry not only provides practically powerful synthetic methods, but the molecular design concept that we have developed may also be adopted to tackle other related chemical problems. [ABSTRACT FROM AUTHOR]

A new and efficient method for the preparation of tri- and difluoromethylsilanes using magnesium metal-mediated reductive tri- and difluoromethylation of chlorosilanes is reported using tri- and difluoromethyl sulfides, sulfoxides, and sulfones. The byproduct of the process is diphenyl disulfide. Since phenyl trifluoromethyl sulfone, sulfoxide, and sulfide are readily prepared from trifluoromethane (CF[sub 3]H) and diphenyl disulfide, the method can be considered to be catalytic in diphenyl disulfide for the preparation of (trifluoromethyl)trimethylsilane (TMS-CF[sub 3]) from non-ozonedepleting trifluoromethane. [ABSTRACT FROM AUTHOR]

The article discusses the author's views on the selective synthesis of fluorine atoms as new fluoroalkylating agents. He cites a study which envisions the concept of chiral fluoroalkylation reagent that can diastereoselective and enantioselective control the nucleophilic reactions using sulfur in sulfoximines. The author hopes that altering the number of atoms in fluorinated sulfoximines can offer more opportunities in the discovery of chiral fluoroalkylating agents and reactions.

The article discusses the study on the major subtypes of obesity such as the general and the abdominal obesity which are known to be associated with chronic diabetes complications, like cardiovascular diseases and diabetic retinopathy. Topics discussed include the diabetic kidney disease (DKD), type 2 diabetes (T2D) patients assess through DXA, and the parameters of general obesity such as body mass index (BMI), total body fat percentage(TBF), and fat mass index (FMI).

A copper-mediated di- and monofluoromethanesulfonylation of arenediazonium tetrafluoroborates using di- and monofluoromethanesulfinate reagents provides aryl difluoromethyl (or monofluoromethyl) sulfones in good yields. It was found that the relative reactivity of these sodium fluoroalkanesulfinates in the present reactions decreases in the following order: CH 2FSO 2Na > CF 2HSO 2Na > CF 3SO 2Na. [ABSTRACT FROM AUTHOR]

The new millennium has witnessed the rapid development of synthetic organofluorine chemistry all over the world, and chemists in China have made significant contributions in this field.This review aims to provide a brief introduction to China's primary innovations from 2000 to early 2017, covering fluorination, fluoroalkylation, fluoromethylthiolation, fluoroolefination and polyfluoroarylation, as well as synthesis with fluorinated building blocks. Recent advances in the chemistry of difluorocarbene and the chemistry of carbon-fluorine bond activation are also discussed. As a conclusion, the review ends with some personal perspectives on the future development of China's synthetic organofluorine chemistry. [ABSTRACT FROM AUTHOR]

INTRODUCTION A large number of people around the world are exposed to the risks of passive smoking. This prospective study aimed to examine the association between secondhand smoke exposure, exposure time, and the incidence of chronic kidney disease (CKD) and determine whether this association was influenced by genetic susceptibility. METHODS The study included 214244 participants of the UK Biobank who were initially free of CKD. Cox proportional hazards model was used to estimate the associations between secondhand smoke exposure time and the risks of CKD in people who have never smoked. The genetic risk score for CKD was calculated by a weighted method. The likelihood ratio test comparing models was used to examine the cross-product term between secondhand smoke exposure and genetic susceptibility to CKD outcomes. RESULTS During a median of 11.9 years of follow-up, 6583 incidents of CKD were documented. Secondhand smoke exposure increased the risk of CKD (HR = 1.09; 95% CI: 1.03-1.16, p<0.01), and a dose-response relationship between CKD prevalence and secondhand smoke exposure time was found (p for trend<0.01). Secondhand smoke exposure increases the risk of CKD even in people who never smoke and have a low genetic risk (HR=1.13; 95% CI: 1.02-1.26, p=0.02). There was no statistically significant interaction between secondhand smoke exposure and genetic susceptibility to CKD (p for interaction=0.80). CONCLUSIONS Secondhand smoke exposure is associated with higher risk of CKD, even in people with low genetic risk, and the relationship is dose dependent. These findings change the belief that people with low genetic susceptibility and without direct participation in smoking activities are not prone to CKD, emphasizing the need to avoid the harm of secondhand smoke in public places. [ABSTRACT FROM AUTHOR]

An efficient copper-catalyzed trifluoromethylation of polysubstituted alkenes assisted by decarboxylation of β,γ-unsaturated carboxylic acids has been achieved. The reaction provides a general method to construct allylic and vinylic CF3-substituted compounds under mild conditions. [ABSTRACT FROM AUTHOR]

The monofluoroalkene motif is important in drug development as it serves as a peptide bond isostere and is found in a number of biologically active compounds with various pharmacological activities. Direct olefination of carbonyl compound is a straightforward way to prepare monofluoroalkenes; however, these methods often result in a mixture of Z- and E-isomers that cannot be easily separated. We discovered a unique spontaneous resolving reaction that simultaneously addresses the problems in the synthesis and separation of Z- and E-monofluoroalkenes. The reaction is accompanied by a highly efficient spontaneous kinetic resolution and phase labeling of monofluoroalkene precursors which allows the separation of Z- and E-monofluoroalkenes by liquid-liquid extraction. The application of the method is demonstrated by the synthesis and separation of potential anticancer agents, which are inseparable by HPLC. [ABSTRACT FROM AUTHOR]

The article presents a study related to use of sulfur based fluorination and fluoroalkylation reagents for organic synthesis. Topics discussed include applications of fluorine based reagents such as role as deoxygenative fluorination reagents for alcohols and aldehydes, sulfur-based fluoroalkylation reagents such as xanthates and sulfoxides, use of the fluoroalkylation reagents in difluoromethylation and monofluoromethylation and trifluoromethylthiolation and pentafluorosulfanylation.

Copper-mediated trifluoromethylation of a-diazo esters with TMSCF3 reagent has been developed as a new method to prepare α-trifluoromethyl esters. This trifluoromethylation reaction represents the first example of fluoroalkylation of a non-fluorinated carbene precursor. Water plays an important role in promoting the reaction by activating the "CuCF3" species prepared from CuI/TMSCF3/CsF (1.0:1.1:1.1). The scope of this trifluoromethylation reaction is broad, and its efficiency is demonstrated in the synthesis of a variety of aryl-, benzyl-, and alkyl-substituted 3,3,3-trifluoropropanoates. [ABSTRACT FROM AUTHOR]

Iodo- and bromodifluoromethylated compounds are important synthetic intermediates and halogen-bond acceptors. However, direct introduction of -CF2I and -CF2Br groups through nucleophilic addition is particularly challenging because of the high tendency of decomposition of CF2Br- and CF2I- to difluorocarbene. In this work, we have developed a formal nucleophilic iodo- and bromodifluoromethylation for carbonyl compounds. The key strategy of the method is the halogenation of in situ-generated sulfinate intermediates from the Julia-Kocienski reaction to change the reaction pathway from the traditional olefination to alkylation. Interesting halogen-π interactions between the halocarbon and aromatic donors were observed in the crystal structures of the products. The method could also be extended to the introduction of other fluorinated groups, such as -CFClBr, -CFClI, -CFBr2, and -CFMeI, which opens up new avenues for the synthesis of a wide range of useful fluorinated products. [ABSTRACT FROM AUTHOR]

The first α-difluoromethyl sulfoximine compound, 2, was successfully prepared by using the copper(II)-catalyzed nitrene transfer reaction. Compound 2was found to be a novel and efficient difluoromethylation reagent for transferring the CF2H group to S-, N-, and C-nucleophiles. Deuterium-labeling experiments suggest that a difluorocarbene mechanism is involved in the current difluoromethylation reactions. [ABSTRACT FROM AUTHOR]

An efficient and practically useful method for the preparation of α-functionalized mono- and difluoro(phenylsulfonyl)methanes by using a nucleophilic fluoroalkylation methodology was developed. α,α-Difluoro-β-ketosulfones, α-monofluoro-β-ketosulfones, and α-fluoro disulfones were successfully prepared in excellent yields by nucleophilic fluoroalkylation of esters and sulfinates with PhSO2CF2H and PhSO2CH2F reagents. [ABSTRACT FROM AUTHOR]

Pregeneration of fluoro(phenylsulfonyl)methyl anion (PhSO2CHF−) paves the way for the efficient and highly stereoselective monofluoromethylation of (R)-N-tert-butylsulfinyl ketimines. The stereocontrol mode of the present diastereoselective monofluoromethylation of ketimines is different from the previously known nucleophilic fluoroalkylation of (R)-N-tert-butylsulfinyl aldimines, which suggests that a cyclic six-membered transition state (rather than a nonchelation controlled one) is involved in the current ketimine reaction. [ABSTRACT FROM AUTHOR]

We have successfully accomplished the nucleophilic fluoroalkylation of α,β-enones, arynes, and activated alkynes with fluorinated sulfones. It was found that for acylic α,β-enones, although the reaction medium and the structure of the enones can all influence the regioselectivity of the nucleophilic alkylation reactions, the hard/soft nature of the carbanions played a major role. By using the 1,4- and 1,2-addition product ratio as a probe to determine the hard/soft nature of the above-mentioned four halogenated carbanions, the order of the softness of these carbanions can be given as follows: [(PhSO2)2CF-] (20) ≈ PhSO2CCl2- (32)> PhSO2CHF- (31) > PhSO2CF2- (30). In the case of fluoroalkylation of aryne (35 as the precursor) and α,β-acetylenic ketones 46 with fluorobis(phenylsulfonyl)methane (21), fluorobis(phenylsulfonyl)m-ethylated arenes 36 and β-fluorobis(phenylsulfonyl)methylated α,β-enones 47 were obtained as the corresponding products in good yields. During the reaction between 2-fluoro-2-(phenylsulfonyl)acetophenone (34) and arynes or activated alkynes 46, an intramolecular tandem reaction process leads to the formation of acyl-fluoroalkylated arenes 43 or α-acyl-β-fluoroalkylated α,β-enones 48. It turned out that the softness of a fluorine-bearing carbanion (such as 20 or 33 derived from 21 or 34) plays a crucial role for the success of the nucleophilic fluoroalkylation reactions with arynes and some activated alkynes (α,β-acetylenic ketones). [ABSTRACT FROM AUTHOR]

A novel and non-ODS-based (ODS = ozone-depleting substance) preparation of 2-chloro-2,2-difluoroacetophenone (1) was achieved in high yield by using 2,2,2-trifluoroacetophenone as the starting material. Compound 1 was found to act as a good difluorocarbene reagent, which readily reacts with a variety of structurally diverse phenol derivatives 4 in the presence of potassium hydroxide or potassium carbonate to produce aryl difluoromethyl ethers 5 in good yields. This new and easy-to-handle synthetic methodology offers an environmentally friendly alternative to other Freon- or Halon-based difluoromethylating approaches. [ABSTRACT FROM AUTHOR]

The unprecedented nucleophilic fluoroalkylation of simple epoxides with fluorinated sulfones was achieved to give the β-fluoroalkyl alcohols in one step. The negative ‘fluorine effect’ in the nucleophilic fluoroalkylation of epoxides with fluorinated carbanions was probed by the reactivity comparison between carbanions PhSO2CF2- (3) and PhSO2CCl2- (4) and between carbanions PhSO2CHF2- (7) and PhSO2CHCl- (13). The mediation of this fluorine effect by introducing another electron-withdrawing benzenesulfonyl group was found to be an effective way to significantly increase the nucleophilicity of the fluorinated carbanions, with the reactivity order [(PhSO2)2CF-] (16) > PhSO2CFH- (7) ⪢ PhSO2CF2- (3). [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) have many potential uses for separations, storage, and catalysis, but their use as intercalation hosts for batteries has been scarce. In this article, we examine the mechanism of Li insertion in a MOF to provide guidance to future design efforts in this area. As a model system, we choose UiO-66, a MOF with the formula (Zr6O4(OH)4)4 (1,4-benzenedicarboxylate)6, as an electrode material for lithium-ion batteries; this MOF is of special interest because the zirconium is not redox active. We report both quantum mechanical characterization of the mechanism and experimental studies in which the material is synthesized as nanoparticles to reduce diffusion lengths for lithium ions and increase the contact area with a conductive carbon phase. The calculated changes in the IR spectra of UiO-66 and lithiated UiO-66 are consistent with the experimental FTIR results. We found experimentally that this MOF can maintain a specific discharge capacity of at least 118 mAh/g for 30 lithiation and delithiation cycles at a rate of C/5, exhibiting good cyclability. Density functional electronic structure calculations show that the charge transfer during lithiation is mainly from Li to node oxygens and carboxylate oxygens, that is, it involves anions rather than cations or aromatic rings, and they provide a mechanistic understanding of the potential for increased Li capacity because the theoretical capacity of UiO-66 with Li at the oxygens in the metal oxide nodes and the carboxylate linkers is more than 400 mAh/g. The lithiation process greatly decreases the bandgap of UiO-66, which is expected to increase its electronic conductivity. The electrode material was also characterized by X-ray diffraction and scanning electron microscopy, which were consistent in confirming that smaller particle sizes were obtained in lower-temperature syntheses. [ABSTRACT FROM AUTHOR]

Plants resist infection through an innate immune response, which is usually associated with slowing of growth. The molecular mechanisms underlying the trade-off between plant growth and defense remain unclear. The present study reveals that growth/defense trade-offs mediated by gibberellin (GA) and salicylic acid (SA) signaling pathways are uncoupled during constitutive overexpression of transgenic AtRAN1 and AtRAN1Q72L (active, GTP-locked form) Arabidopsis plants. It is well known that the small GTP-binding protein Ran (a Ras-related nuclear protein) functions in the nucleus-cytoplasmic transport of proteins. Although there is considerable evidence indicating that nuclear-cytoplasmic partitioning of specific proteins can participate in hormone signaling, the role of Ran-dependent nuclear transport in hormone signaling is not yet fully understood. In this report, we used a combination of genetic and molecular methods to reveal whether AtRAN1 is involved in both GA and SA signaling pathways. Constitutively overexpressed AtRAN1 promoted both elongation growth and the disease resistance response, whereas overexpression of AtRAN1Q72L in the atran2atran3 double mutant background clearly inhibited elongation growth and the defense response. Furthermore, we found that AtRAN1 coordinated plant growth and defense by promoting the stability of the DELLA protein RGA in the nucleus and by modulating NPR1 nuclear localization. Interestingly, genetically modified rice (Oryza sativa) overexpressing AtRAN1 exhibited increased plant height and yield per plant. Altogether, the ability to achieve growth/defense trade-offs through AtRAN1 overexpression provides an approach to maximizing crop yield to meet rising global food demands. [ABSTRACT FROM AUTHOR]

The diastereoselective nucleophilic (phenylsulfonyl)difluoromethylation and (phenylsulfonyl)monofluoromethylation of α-amino N-tert-butanesulfinimines (3) by using PhSO2- c:F2H and PhSO2CH2F reagents gave products 4 or 5 in high yields (73-99%) and with excellent diastereoselectivity (dr up to >99%). After subsequent reductive desulfonylation and acid-catalyzed alcoholysis, compounds 4 and 5 could be readily transformed to chiral α-difluoromethylated or α-monofluromethylated ethylenediamines in good yields. [ABSTRACT FROM AUTHOR]

Bisphenol-A (BPA) is a common environmental pollutant, and expo sure to it is associated with proteinuria and may predict the progression of chronic kid ney disease; however, the mechanism is not clear. Neutrophil extracellular traps (NET s) are a DNA skeleton coated with various proteases, and it is associated with variou s types of autoimmune nephritis. In this study, we examine whether NETs is involved i n BPA-induced chronic kidney injury. In vivo, BPA exposure resulted in impaired renal function and altered renal morphology, including glomerular mesangial matrix expansion and increased renal interstitial fibroblast markers. Meanwhile, more dsDNA can be de tected in the serum, and the NETs-associated proteins, MPO and citH3 were deposited in the renal system. In vitro, BPA and NETs treatment caused podocyte injury, a loss of mark er proteins and disorder in the actin skeleton. After NETs inhibition via D Nase administration, BPA-induced injuries were significantly relieved. In conclusion, the increase of NETosis in circulation and the renal system during BPA exposure suggest s that NETs may be involved in BPA-induced chronic kidney injury. [ABSTRACT FROM AUTHOR]

Aims The relationship between bisphenol A (BPA) and diabetes remains controversial. This study aims to investigate whether serum BPA level could predict the 5-year incidence of type 2 diabetes (T2D). Methods A nested case–control study was performed among Chinese who participated in the environment, inflammation and metabolic diseases study (2008–2013). Of the 3510 subjects who were free of diabetes, 232 subjects developed diabetes during the 5-year follow-up. Cases and controls were matched for age and gender by a ratio of 1:1. Homoeostasis model assessment was used to estimate basal β-cell function (HOMA-β) and insulin resistance (HOMA-IR). Participants were stratified into tertiles based on low, median and high baseline serum BPA levels. Regression models were used to analyze the relationship between serum BPA concentration and the incidence of T2D. Results At baseline, no significant difference in serum BPA concentration was observed between patients with T2D and controls [1.3 (0.3, 3.7) vs. 1.6 (0.4, 3.9) μmol/L, P = 0.199]; serum BPA concentration was positively associated with fasting plasma glucose (r = 0.27, P < 0.001); however, neither HOMA-β nor HOMA-IR correlated with serum BPA concentration. During the follow-up, baseline BPA levels could not predict the 5-year T2D incidence, whether or not adjusted for the potential confounders such as body mass index and blood pressure. [Low BPA tertile was the reference, OR 0.66 (95% CI 0.30, 1.44) for median, OR 0.93 (95% CI 0.41, 2.13) for high.] Conclusion BPA is not associated with a 5-year T2D incidence. These data do not support previous cross-sectional study that BPA exerted a detrimental effect on glucose metabolism. [ABSTRACT FROM AUTHOR]

We report the first iron-catalyzed difluoromethylation of arylzincs with difluoromethyl 2-pyridyl sulfone via selective C-S bond cleavage. This method employs the readily available, bench-stable fluoroalkyl sulfone reagent and inexpensive iron catalyst, allowing facile access to structurally diverse difluoromethylated arenes at low temperatures. The experiment employing a radical clock indicates the involvement of radical species in this iron-catalyzed difluoromethylation process. [ABSTRACT FROM AUTHOR]

An atom-economical method for radical (phenylsulfonyl)difluoromethylation of isocyanides with PhSO2CF2H under transition-metal-free conditions has been developed. A PhSO2CF2 radical is generated through the oxidation of PhSO2CF2- after the deprotonation of PhSO2CF2H in one pot. The reaction exhibits excellent functional-group tolerance and the resulting products can be further modified with the removal of a PhSO2 group to give other CF2-containing compounds. [ABSTRACT FROM AUTHOR]

A new strategy for the synthesis of aryl trifluoromethyl ethers (ArOCF3) by combining O-carboxydifluoromethylation of phenols and subsequent decarboxylative fluorination is reported. This protocol allows easy construction of functionalized trifluoromethoxybenzenes and trifluoromethylthiolated arenes (ArSCF3) in moderate to good yields. Moreover, it utilizes accessible and inexpensive reagents sodium bromodifluoroacetate and SelectFluor II and, thus, is practical for O-trifluoromethylation of phenols. The potential application of this method is demonstrated with the preparation of a plant-growth regulator, Flurprimidol. [ABSTRACT FROM AUTHOR]

A new olefination protocol for transition-metal-free cross-coupling of two carbene fragments arising from two different sources, namely, a nonfluorinated carbene fragment resulting from a diazo compound and a difluorocarbene fragment derived from Ruppert-Prakash reagent (TMSCF3) or TMSCF2Br, has been developed. This gem-difluoroolefination proceeds through the direct nucleophilic addition of diazo compounds to difluorocarbene followed by elimination of N2. Compared to previously reported Cucatalyzed gem-difluoroolefination of diazo compounds with TMSCF3, which possesses a narrow substrate scope due to a demanding requirement on the reactivity of diazo compounds and in-situ-generated CuCF3, this transition-metal-free protocol affords a general and efficient approach to various disubstituted 1,1-difluoroalkenes, including difluoroacrylates, diaryldifluoroolefins, as well as arylalkyldifluoroolefins. In view of the ready availability of diazo compounds and difluorocarbene reagents and versatile transformations of 1,1-difluoroalkenes, this new gem-difluoroolefination method is expected to find wide applications in organic synthesis. [ABSTRACT FROM AUTHOR]

The first palladium-catalyzed direct monofluoromethylation of arylboronic esters to produce monofluoromethyl arenes is reported. The reaction is typically carried out at room temperature within 4 h and has a good functional group tolerance. The monofluoromethylating agent, CH2FI, was readily prepared via a halogen-exchange process. [ABSTRACT FROM AUTHOR]

Fluorinated sulfinate salts RfSO2Na (Rf = CF2H, CF2Ph, and CH2F) have been prepared via NaBH4-mediated reduction of the corresponding benzo[d]thiazol-2-yl sulfones, and their synthetic application as di- and monofluoroalkyl radical precursors is demonstrated in the silver-catalyzed cascade fluoroalkylation/aryl migration/SO2 extrusion of conjugated N-arylsulfonylated amides. [ABSTRACT FROM AUTHOR]

Background We sought to determine the comparative diagnostic performance of standard b-value (800-1000 s/mm² ) versus low b-value (400-500 s/mm²) diffusion-weighted magnetic resonance imaging (DW-MRI) in the detection of renal cell carcinoma (RCC). Method After a systematic review of the available literature, studies were included that reported b-values, used a histopathological reference standard, and allowed construction of 2 x 2 contingency tables for detection of RCC lesions using DW-MRI. In addition, a summary receiver operating characteristic (SROC) analysis was performed. Results Four articles that complied with all inclusion and exclusion criteria were selected for data extraction and analysis (n = 248 lesions in 266 patients). All four studies were high quality. Standard b-value DW-MRI displayed a pooled sensitivity of 0.59 (95% confidence interval (CI): 0.51-0.67) and a pooled specificity of 0.50 (95% CI: 0.30-0.70), while low b-value DW- MRI displayed a pooled sensitivity of 0.58 (95% CI: 0.48-0.63) and a pooled specificity of 0.23 (95% CI: 0.09-0.44). The SROC curve of standard b-value DW-MRI displayed an AUC of 0.61 and a Q*index of 0.59, while the SROC curve of low b-value DW-MRI displayed an AUC of 0.68 and a Q*index of 0.64. Conclusion Standard b-value DW-MRI showed a superior specificity but an approximately equivalent sensitivity to low b-value DW-MRI in detecting RCC lesions in the kidney. However, low b- value DW-MRI displayed an overall superior diagnostic accuracy over standard b-value DW-MRI. [ABSTRACT FROM AUTHOR]

Background: We sought to determine the comparative diagnostic performance of standard b-value (800-1000 s/mm²) versus low b-value (400-500 s/mm²) diffusion-weighted magnetic resonance imaging (DW-MRI) in the detection of renal cell carcinoma (RCC). Method: After a systematic review of the available literature, studies were included that reported b-values, used a histopathological reference standard, and allowed construction of 2 × 2 contingency tables for detection of RCC lesions using DW-MRI. In addition, a summary receiver operating characteristic (SROC) analysis was performed. Results: Four articles that complied with all inclusion and exclusion criteria were selected for data extraction and analysis (n = 248 lesions in 266 patients). All four studies were high quality. Standard b-value DW-MRI displayed a pooled sensitivity of 0.59 (95% confidence interval (CI): 0.51-0.67) and a pooled specificity of 0.50 (95% CI: 0.30-0.70), while low b-value DW-MRI displayed a pooled sensitivity of 0.58 (95% CI: 0.48-0.63) and a pooled specificity of 0.23 (95% CI: 0.09-0.44). The SROC curve of standard b-value DW-MRI displayed an AUC of 0.61 and a Q*index of 0.59, while the SROC curve of low b-value DW-MRI displayed an AUC of 0.68 and a Q*index of 0.64. Conclusion: Standard b-value DW-MRI showed a superior specificity but an approximately equivalent sensitivity to low b-value DW-MRI in detecting RCC lesions in the kidney. However, low b-value DW-MRI displayed an overall superior diagnostic accuracy over standard b-value DW-MRI. [ABSTRACT FROM AUTHOR]

This paper describes the design and fabrication of ion-sensing electrochemical paper-based analytical devices (EPADs) in which a miniaturized paper reference electrode is integrated with a small ion-selective paper electrode (ISPE) for potentiometricmeasurements. Ion-sensing EPADs use printed wax barriers to define electrochemical sample and reference zones. Single-layer EPADs for sensing of chloride ions include wax-defined sample and reference zones that each incorporate a Ag/AgCl electrode. In EPADs developed for other electrolytes (potassium, sodium, and calcium ions), a PVC-based ion-selective membrane is added to separate the sample zone from a paper indicator electrode. After the addition of a small volume (less than 10 µL) of sample and reference solutions to different zones, ion-sensing EPADs exhibit a linear response, over 3 orders of magnitude, in ranges of electrolyte concentrations that are relevant to a variety of applications, with a slope close to the theoretical value (59.2/z mV). Ion-selective EPADs provide a portable, inexpensive, and disposable way of measuring concentrations of electrolyte ions in aqueous solutions. [ABSTRACT FROM AUTHOR]

An unprecedented [3+2] cycloaddition between N-tert-butanesulfinyl imines and arynes provides a stereoselective method for the synthesis of cyclic sulfoximines. Not only does the difluoro(phenylsulfonyl)methyl group play an important role in facilitating the cycloaddition reaction, it can also be removed or substituted through the transformation of the difluorinated cyclic sulfoximines to cyclic sulfinamides. [ABSTRACT FROM AUTHOR]

A novel Cu-catalyzed gem-difluoroolefination of diazo compounds is described. This transformation starts from readily available TMSCF3 and diazo compounds, via trifluoromethylation followed by C–F bond cleavage, to afford the desired 1,1-difluoroalkene products. [ABSTRACT FROM AUTHOR]