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The critical nucleus forms only when the three types of atoms arrange in terms of the β-W unit cell.

Cyclopropyldiphenylsulfonium salt, a famous ylide precursor previously extensively employed in the preparation of cyclic compounds, has been successfully utilized as an efficient allylation reagent in this work. The copper-catalyzed reactions of cyclopropyldiphenylsulfonium trifluoromethanesulfonate with amines in the presence of an appropriate ligand provided the N-allylated products in good yields. Aliphatic/aromatic amines and primary/secondary amines were all converted under mild reaction conditions. This protocol was also applicable to N-functionalization of drug molecules, supplying the corresponding N-allylated compounds in satisfactory yields. The reaction, which showed good functional group tolerance with a wide range of substrates and excellent chemoselectivity, offers an interesting method for the synthesis of N-allyl amines.

Catalyst-free visible-light irradiation has leveraged the big redox potential gaps between arylsulfonium salts and [Me4N][SeCF3], which combined with sulfenylation processes offers convenient and selective C–H trifluoromethylselenolation.

During the tension process, single crystal and polycrystal bear plastic strain through stacking faults and grain boundaries, respectively. In addition metallic glass bears plastic strain through tacking faults and grain boundaries.

The application of alkylsulfonium salts as alkyl-transfer reagents in organic synthesis has reemerged over the past few years. Numerous heteroatom- and carbon-centered nucleophiles, alkenes, arenes, alkynes, organometallic reagents, and others are readily alkylated by alkylsulfonium salts under mild conditions. The reactions feature convenience, high efficiency, readily accessible and structurally diversified alkylation reagents, good functional group tolerance, and a wide range of substrate types, allowing the facile synthesis of various useful organic molecules from commercially available building blocks. This review summarizes alkylation reactions using either isolated or in situ formed alkylsulfonium salts via nucleophilic substitution, transition-metal-catalyzed reactions, and photoredox processes.1 Introduction2 General Methods for the Synthesis of Alkylsulfonium Salts3 Electrophilic Alkylation Using Alkylsulfonium Salts4 Transition-Metal-Catalyzed Alkylation Using Alkylsulfonium Salts5 Photoredox-Catalyzed Alkylation Using Alkylsulfonium Salts6 Conclusion

Diarylamines are important moieties in organic materials and bioactive molecules. The traditional synthetic approach to diarylamines is metal catalysis in organic solvents. Herein, we report the chemoenzymatic cascade synthesis of phenol diarylamines. Non-heme diiron N-oxygenase AzoC, which catalyzes the oxidization of amines to nitroso groups for azoxymycins biosynthesis in Streptomyces chattanoogensis, is engineered as a catalyst. This synthetic method bears a broad range of phenol and aniline substrates. Mechanistic study indicates that the enzymatically formed nitroso intermediate couple to phenoxide facilitates the non-enzymatic diarylamine synthesis. Our study suggests that diarylamines can be enzymatic synthesized in aqueous solutions and highlights the synthetic potential of non-heme diiron N-oxygenases.

A highly efficient method for the selective formal C-H/C-H cross-coupling of azoles and (hetero)arenes was established through arylsulfonium intermediates under transition-metal catalysis, which produced a variety of 2-(hetero)aryl azoles in good to excellent yields. Advantages of the reaction included mildness, a good functional group tolerance, a wide range of substrates, a high regio- and chemoselectivity, one-pot procedures, and the late-stage functionalization of complex molecules without the use of oxidants, offering a promising strategy for the transition-metal-catalyzed C-H arylation of azoles.

Cardiac myxoma is a common cardiac tumor. Most are found in the left cardiac system, of which 75% of myxomas are located in the left atrium [Pinede 2001], and the origin of the left ventricle is relatively rare. Surgical resection is the most effective method for the treatment of myxoma, but because of the complex anatomy of the left ventricle, most of the reported cases are performed through the traditional median thoracotomy through the ascending aorta and vena cava to establish cardiopulmonary bypass. It is rare to establish cardiopulmonary bypass through the femoral artery and femoral vein to remove left ventricular myxoma under complete video-assisted thoracoscopy. This paper reports the surgical process and perioperative echocardiographic, magnetic resonance, radiological and pathological features of a completely thoracoscopic resection of left ventricular myxoma.

A convenient method for deoxyfluorination of aromatic and aliphatic carboxylic acids with CF3 SO2 OCF3 in the presence of a suitable base at room temperature has been developed. The reaction allows a straightforward access to a variety of acyl fluorides and proves that CF3 SO2 OCF3 is an effective deoxyfluorination reagent for carboxylic acids. The method features simplicity, expeditiousness, high efficiency, ease of handling, good functional group tolerance, a wide range of substrates, excellent yields of products, compatibility of many amine initiators, use of environmentally friendly reagents, and effortless removal of byproducts. This reaction represents the first utilization of trifluoromethyl trifluoromethanesulfonate as a fluorination reagent.

Objective The current study aimed to investigate the prevalence and risk factors of restless legs syndrome (RLS) in patients undergoing hemodialysis, as well as the mortality and risks of cardiovascular and cerebrovascular events. Methods A total of 354 hemodialysis patients from four hospitals were enrolled. RLS was diagnosed using the International RLS Study Group (IRLSSG) criteria. The patients were evaluated face-to-face using the IRLSSG rating scale, Epworth Sleepiness Scale (ESS), Hamilton Anxiety Scale, Hamilton Depression Scale, and Pittsburgh Sleep Quality Index (PSQI). The patients were followed up for 9 months. Death was considered an endpoint event. The cardiovascular and cerebrovascular events were investigated. Results The prevalence of RLS in hemodialysis patients was 40.7% and was associated with factors such as duration of hemodialysis, hypersensitive C-reactive protein, hyperparathyroidism, glycosylated serum protein, and erythropoietin treatment. The scores of the PSQI, ESS, and Hamilton Depression Scale in the RLS group were significantly higher than those in the non-RLS group (p < 0.05). During follow-ups, the incidence rate of cardiovascular diseases was 18.8% in the RLS group and 8.6% in the non-RLS group (p < 0.005). The IRLSSG rating scores were significantly higher in RLS patients with kidney transplantation failure compared with those without transplantation (p < 0.05). Conclusion The prevalence of RLS was high in hemodialysis patients. The risk factors of RLS included duration of hemodialysis, hypersensitive C-reactive protein, hyperparathyroidism, glycosylated serum protein, and erythropoietin treatment. RLS affected sleep quality and emotion and increased the risk of cardiovascular diseases in hemodialysis patients. RLS was more severe in patients with kidney transplantation failure compared with those without transplantation.

Objective To investigate the sonosensitivity of N2O-microbubbles (N2O-mbs) and its sonodynamic effect on tumor cells. Methods The N2O-mbs were prepared by improved mechanical oscillation method. The basic characteristics of N2O-mbs were determined. The cytotoxicity of these microbubbles was evaluated by CCK-8 assay. The delivery efficiency of N2O-mbs to MDA-MB-231 cells was observed under a laser scanning confocal microscope. The sonosensitivity of N2O-mbs was evaluated by singlet oxygen sensor green (SOSG) assay and reactive oxygen species assay kit, which detected its extracellular and intracellular reactive oxygen species generation. In vitro sonodynamic properties of N2O-mbs on tumor cells were evaluated by CCK-8 assay, flow cytometry and CAM/PI double staining. Results These N2O-mbs presented with homogenized size distribution and milky white suspensions after water reconstitution. The average diameter of N2O-mbs was (458.10±17.26) nm and its zeta potential was (–16.20±0.35) mV. N2O-mbs exhibited a good biocompatibility and had an obvious delivery efficiency in cancer cells in vitro. These microbubbles could generate singlet oxygen (1O2) in aqueous solution and produce reactive oxygen species in the cells after irradiation with low intensity focused ultrasound (LIFU). Further, CCK-8 test results suggested N2O-mbs combined with LIFU action would cause a significant decrease in cell viability. Flow cytometry results showed a significant advanced apoptosis in cancer cells. A large number of dead cells were also observed using a laser scanning confocal microscope after N2O-mbs combined with LIFU treatment. Conclusion N2O-mbs has extraordinary sonosensitivity under the condition of microbubble encapsulation and could effectively kill tumor cells though sonodynamic effects in vitro. DOI: 10.11855/j.issn.0577-7402.2019.12.02

The topologically close-packed (TCP) structural characteristics in a model metallic glass (MG) of Cu

After nucleation, metastable HCP regions experience the following 3 stages: HCP–FCC transformation, region regularization, and dislocation pinning or HCP–FCC transformation again.

The potential of (2-bromoethyl)diphenylsulfonium triflate to be a powerful vinylation reagent was determined by the Sonogashira cross-coupling reactions with terminal alkynes. The vinylation proceeded smoothly at 25 °C under Pd/Cu catalysis to afford a variety of 1- and 2-unsubstituted 1,3-enynes in moderate to excellent yields. This protocol represents the first application of (2-haloethyl)diphenylsulfonium triflate as a CH═CH2 transfer source in organic synthesis.

Background Recent studies have suggested that cerebral ischemic infarction may contribute to the development of restless legs syndrome (RLS). This study analyzed the clinical and radiological profiles of RLS with onset after acute lacunar infarction. Methods In this retrospective study we enrolled 244 consecutive patients with acute lacunar infarction between January 2012 and June 2014. RLS was identified and evaluated based on the International RLS Rating Scale (IRLS-RS). Individual sleep quality was assessed using the Epworth Sleepiness Scale (ESS). Psychological state was also assessed using the Hamilton Depression Scale (HDS) and the Hamilton Anxiety Scale (HAS). Results The incidence of RLS in patients with lacunar infarction was 5.33%. Our participant group consisted of nine males and four females. Three patients had symptoms in bilateral limbs, and 10 patients had symptoms only contralateral to the cerebral infarction. The infarctions were localized to the pons, centrum semiovale, thalamus, putamen, medulla, and occipital lobe. Contralateral paralysis was found in 13 patients, and contralateral sensory deficit in seven patients. The average IRLS-RS, ESS, HDS, HAS scores were 19.07 ± 8.70, 4.69 ± 5.82, 4.38 ± 4.68, and 3.85 ± 4.76, respectively. Nine patients had diabetes mellitus. After administration of dopaminergic drugs, patients’ RLS significantly improved. Conclusions The incidence of RLS after acute lacunar infarction was 5.33%. Pons, centrum semiovale, and basal ganglia were the common locations of responsible lesions. Compared to idiopathic RLS, symptoms of RLS after acute lacunar infarction appeared more unilateral and more likely involved the arm. Moreover, diabetes mellitus may be a risk factor for RLS in stroke patients.

A convenient method for deoxyfluorination of aromatic and aliphatic carboxylic acids with CF

Triarylsulfonium, alkyl- and fluoroalkyl(diaryl)sulfonium, and aryl(dialkyl)sulfonium triflates are successfully used as a new family of cross-coupling participants in the Sonogashira reaction as aryldiazonium, diaryliodonium, and tetraphenylphosphonium salts. It was found that terminal alkynes reacted mildly with triarylsulfonium or (2,2,2-trifluoroethyl)diphenylsulfonium triflate at room temperature under Pd- and Cu-cocatalysis to give the corresponding arylalkynes in up to >99% yield. This protocol represents the first use of arylsulfonium salts as cross-coupling partners in the Pd/Cu-catalyzed Sonogashira reaction.

Objective: Pontine infarction is a common type of stroke in the cerebral deep structures, resulting from occlusion of small penetrating arteries, may manifest as hemi-paralysis, hemi-sensory deficit, ataxia, vertigo, and bulbar dysfunction, but patients presenting with restless legs syndrome (RLS) are extremely rare. Herein, we reported five cases with RLS as a major manifestation of pontine infarction. Methods: Five cases of pontine infarction related RLS were collected from July 2013 to February 2016. The diagnosis of RLS was made according to criteria established by the International RLS Study Group (IRLSSG) in 2003. Neurological functions were assessed according to the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS). Severity of RLS was based on the International RLS Rating Scale (IRLS-RS). Sleep quality was assessed by Epworth Rating Scale (ERS), and individual emotional and psychological states were assessed by Hamilton Depression Scale (HDS) and Hamilton Anxiety Scale (HAS). Results: The laboratory data at the onset including hemoglobin, serum concentration of homocysteine, blood urea nitrogen (BUN), creatinine, electrolytes, and thyroid hormones were normal. The electroencephalogram (EEG), lower-extremity somatosensory evoked potential (SEP), and nerve conduction velocity (NCV) in four limbs were normal. The average period of follow-up was 34.60 ± 12.76 months. The MRI examination showed acute or subacute pontine infarction lesions, 3 cases in the rostral inner side, 1 case in the rostral lateral and inner side, and 1 case in rostral lateral side. The neurological deficits included weakness in 4 cases, contralateral sensory deficit in 1 case, and ataxia in 2 cases. All 5 patients presented with symptom of RLS at or soon after the onset of infarction and 4 patients experienced uncomfortable sensations in the paralyzed limbs contralateral to the ischemic lesion. Their neurological deficits improved significantly 2 weeks later, but the symptoms of RLS did not resolve. Among them, 3/5 patients were treated with dopaminergic drugs. At the end of the follow-up, RLS symptom eventually resolved in 3 patients but persisted in two. The IRLS-RS, NIHSS and mRS scores were significantly lower at the onset than those at the last follow-up (P = 0.035, 0.024 and 0.049, respectively). However, there was no significant difference in the ERS, HDS and HAS scores (P = 0.477, 0.226 and 0.778, respectively). Conclusion: RLS can be an onset manifestation of pontine infarction, clinicians should be aware of this potential symptom. RLS usually occurs in the paralyzed limbs contralateral to the infarction lesion. The pathogenesis still needs further investigation. Keywords: Restless legs syndrome, Pontine infarction, Clinical features

Objective The current study aimed to investigate the prevalence and risk factors of restless legs syndrome (RLS) in patients undergoing hemodialysis, as well as the mortality and risks of cardiovascular and cerebrovascular events. Methods A total of 354 hemodialysis patients from four hospitals were enrolled. RLS was diagnosed using the International RLS Study Group (IRLSSG) criteria. The patients were evaluated face-to-face using the IRLSSG rating scale, Epworth Sleepiness Scale (ESS), Hamilton Anxiety Scale, Hamilton Depression Scale, and Pittsburgh Sleep Quality Index (PSQI). The patients were followed up for 9 months. Death was considered an endpoint event. The cardiovascular and cerebrovascular events were investigated. Results The prevalence of RLS in hemodialysis patients was 40.7% and was associated with factors such as duration of hemodialysis, hypersensitive C-reactive protein, hyperparathyroidism, glycosylated serum protein, and erythropoietin treatment. The scores of the PSQI, ESS, and Hamilton Depression Scale in the RLS group were significantly higher than those in the non-RLS group (p < 0.05). During follow-ups, the incidence rate of cardiovascular diseases was 18.8% in the RLS group and 8.6% in the non-RLS group (p < 0.005). The IRLSSG rating scores were significantly higher in RLS patients with kidney transplantation failure compared with those without transplantation (p < 0.05). Conclusion The prevalence of RLS was high in hemodialysis patients. The risk factors of RLS included duration of hemodialysis, hypersensitive C-reactive protein, hyperparathyroidism, glycosylated serum protein, and erythropoietin treatment. RLS affected sleep quality and emotion and increased the risk of cardiovascular diseases in hemodialysis patients. RLS was more severe in patients with kidney transplantation failure compared with those without transplantation.

A palladium/copper-cocatalyzed Ullmann-type N-arylation of anilines using alkyl(aryl)sulfonium triflates as arylation reagents has been accomplished. The reaction enabled Caryl–S bond cleavage over Calkyl–S bond breakage of alkyl(aryl)sulfoniums by Pd(P(tBu)3)2/CuI and gave the corresponding N-arylated products in good to high yields. It was also significant that the reactions of aniline with asymmetric butyl(mesityl)(aryl)sulfonium triflates showed excellent selectivity, in which the aryl groups other than the bulky and electron-rich mesityl moieties were transformed.

It is difficult to investigate the behavior of solitons in realistic inhomogeneity media in experiment due to inhomogeneity of the media and noise from the unwanted coupling. We propose to use a waveguide-like transmission line which is based on direct-current super-conducting quantum interference devices to simulate behavior of solitons because we find that the behavior of the node flux in this transmission is similar to that of solitons with variable mass.

A simple and efficient method for transition-metal-free N-arylation of various amines by triarylsulfonium triflates is described. Both aliphatic and aromatic amines were smoothly converted at 80 °C in the presence of tBuOK or KOH to give the corresponding mono N-arylated products in good to high yields. The molar ratios of the reactants and the choice of bases had a big effect on the reaction. When a large excess of [Ph3 S][OTf] and tBuOK were employed for primary amines under the standard conditions, the bis(N-phenyl) products were predominantly formed. This method was also applicable to the synthesis of bioactive N-phenyl amino acid derivatives. The control experiments, the deuterium labelling study, and the presence of regioisomers of N-arylated products when using 4-substituted triarylsulfonium triflates suggested that the reaction might proceed through an aryne intermediate. The present protocol demonstrated that triarylsulfonium salts are versatile arylation reagents in the construction of CAr -N bonds.

Though traditional methods could recognize some facies, e.g. lagoon facies, backshoal facies and foreshoal facies, they couldn’t recognize reef facies and shoal facies well. To solve this problem, back propagation neural network (BP-ANN) and an improved BP-ANN with better stability and suitability, optimized by a particle swarm optimizer (PSO) algorithm (PSO-BP-ANN) were proposed to solve the microfacies’ auto discrimination of M formation from the R oil field in Iraq. Fourteen wells with complete core, borehole and log data were chosen as the standard wells and 120 microfacies samples were inferred from these 14 wells. Besides, the average value of gamma, neutron and density logs as well as the sum of squares of deviations of gamma were extracted as key parameters to build log facies (facies from log measurements)—microfacies transforming model. The total 120 log facies samples were divided into 12 kinds of log facies and 6 kinds of microfacies, e.g. lagoon bioclasts micrite limestone microfacies, shoal bioclasts grainstone microfacies, backshoal bioclasts packstone microfacies, foreshoal bioclasts micrite limestone microfacies, shallow continental micrite limestone microfacies and reef limestone microfacies. Furthermore, 68 samples of these 120 log facies samples were chosen as training samples and another 52 samples were gotten as testing samples to test the predicting ability of the discrimination template. Compared with conventional methods, like Bayes stepwise discrimination, both the BP-ANN and PSO-BP-ANN can integrate more log details with a correct rate higher than 85%. Furthermore, PSO-BP-ANN has more simple structure, smaller amount of weight and threshold and less iteration time.

Flexibility was very important for molecularly imprinted membrane (MIM) to apply to practical use. A novel free-standing flexible MIM was prepared using methacrylic acid (MAA) and 2-hydroxyethyl acrylate (HEA) as co-functional monomer, and ionic liquid as porogen. HEA was able to effectively improve the flexibility of MIM. Ionic liquid, 1-butyl-3-methylimidazolium bromide, was able to accelerate the synthesis process and improve the selectivity and adsorption of the MIM. The properties of MIM were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), thermo gravimetric analysis (TGA), differential thermal analysis (DTA) and X-ray photoelectron spectroscopy (XPS). Two structurally similar compounds (octopamine and tyramine) were selected as competitors to examine the selective recognition of MIM to synephrine (SYN). The competitive adsorption and permeation selectivity experiments showed that the MIM could selectively recognize SYN, and was able to be used to selectively separate SYN from the standard mixtures or the extract of stir-baked Aurantii Fructus Immaturus in methanol/water (4:1, v/v) media.

In order to detect Internet Explorer browser vulnerabilities, the miner distributed with test method based on the DOM tree are designed and implemented, it also implemented dynamic selection of the test case execution, experiment results found 50 IE vulnerabilities.

Uniformly sized synephrine molecularly imprinted polymer (MIP) microparticles were prepared via precipitation polymerization. The presence of the template, the amount of monomer, crosslinker, and porogenic solvent could affect the size distribution and morphology of the polymers. The pseudo-second-order kinetic model could provide a better correlation for the adsorption than the pseudo-first-order model. The intraparticle diffusion study showed that the sorption involved intraparticle diffusion, but that was not the only rate-controlling step. The equilibrium data better fit the Freundlich model than the Langmuir model. The Scatchard plot of MIPs revealed MIPs had two groups of sites with different affinities. Subsequent recognition selectivity experiments demonstrated preferential structural selectivity for synephrine with respect to other structurally similar compounds (i.e., octopamine and tyramine). Compared with the bulk MIP of SYN, the SYN MIP microparticles in this work had higher adsorption select...

A novel molecularly imprinted polymer (MIP) using the specific ionic liquid (i.e. 1-vinyl-3-carboxymethylimidazolium bromide, 1-vinyl-3-carboxyethylimidazolium bromide, 1-viny-3-carboxybutylimidazolium bromide, or 1-vinyl-3-carboxypentylimidazolium bromide) as functional monomer was prepared via precipitation polymerization, which can be used to selectively separate synephrine (SYN) from methanol-water media. Ionic liquids are facile to be designed with varying the cation or anion, which enables the specific ionic liquid to be effectively designed to be a functional monomer for the preparation of MIP. The MIP showed a good selectivity and high adsorption capacity for SYN in methanol-water media. The adsorption process could be described by the pseudo-first-order model, which meant that the adsorption kinetics described a diffusion-controlled process. The equilibrium data fitted well to the Freundlich model, indicating multilayer adsorption. Finally, the MIP were successfully applied as sorbent to selectively enrich and separate SYN from the extracts of Aurantii Fructus Immaturus with a relatively high recovery (80-90%).

A molecular dynamics simulation study was performed to investigate the formation and evolution mechanisms of nano-clusters during the rapid solidification of liquid Ca 70 Mg 30 alloy. The cluster-type index method (CTIM) was adopted to describe microstructure evolutions of nano-clusters during solidification. Results indicate that amorphous structure is mainly formed with three bond-types of 1551, 1541 and 1431 at the cooling rate of 5×10 11 K/s, and glass transition temperature T g is about 530 K; the icosahedron cluster of (12 0 12 0) plays a key role in formation of amorphous structure, and smaller Mg atoms are much more probable to be central atoms of icosahedron clusters; and nano-clusters are mainly formed by combining medium-size clusters. Interestingly, it was also found that formation and evolution processes of the nano-cluster display a three-stage feature which is analogous to crystallization process of amorphous alloy.

The solubilities of rutaecarpine in 12 organic solvents (dichloromethane, ethyl acetate, acetone, trichloromethane, ethoxyethane, butyl alcohol, isopropyl alcohol, ethyl alcohol, methyl alcohol, cy...

The values of the solubility of evodiamine in chloroform, dichloromethane, acetone, ethyl acetate, 1-butanol, isopropanol, ethanol, methanol, ethyl ether, cyclohexane, n-pentane and n-hexane were measured at T = (283.2, 293.2, 303.2, 313.2, and 323.2) K. The solubility of evodiamine in all the organic solvents studied increases with the increase of the temperature. The experimental solubility values were correlated by a simplified thermodynamic equation and the modified Apelblat equation. The values of the dissolution enthalpy and entropy of evodiamine in all organic solvents were calculated using the van’t Hoff equation. The findings showed that the dissolution process was endothermic and entropy-driven. These data of solubility can be used to guide the processes of extraction, purification in the industry.

To improve the efficiency of heat utilization on domestic gas-cooker, the reasons of low-heat efficiency and the factors which influence the measurement of heat efficiency were analyzed in this paper. A new energy-saving apparatus of domestic gas-cooker is developed by the preparation of special heat-insulating material, heat reflecting paint and the use of multilayer, scraggly and crossed abdominal fire rings. Meanwhile, the special designs with resort chambers of flame and the micropores can contribute to the circulation of combustion-supporting hot air. It has also demonstrated that the design increased evidently the detention and reflection of heat. Test results show that the efficiency of gas combustion and the heat utilization were effectively improved.