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Green vortex-assisted octanoic acid-ethanol-water supramolecular solvents (OAEW-SUPRAS) were developed for the simultaneous extraction of six phenolics and hydroxy-α-sanshool (HAS) from Zanthoxylum bungeanum Maxim. peels (ZBMP). The formation of OAEW-SUPRAS was composed of reverse micelle droplets with different sizes, which were caused by desolvation and aggregation. OAEW-SUPRAS were characterized by microscopy and Fourier transform infrared spectroscopy. OAEW-SUPRAS can quickly extract active ingredients with different polarity and obtain excellent extraction yields (9.62 mg/g for phenolics and 41.08 mg/g for HAS). The proposed method was reliable (determination coefficients >0.99), precise (intra-day precision 0.99) were proved a good fit with the extraction process. Under the optimal conditions, the efficiencies of active ingredients extracted by OAEW-SUPRAS were substantially higher than conventional organic reagents and the OAEW-SUPRAS extracts also showed a high antioxidant capacity (IC50 = 1.49 mg/mL). Finally, the extraction solvent and target compounds were easily recovered and enriched.

Resveratrol, as a natural antioxidant, has been studied widely for its antioxidant, anti-inflammatory, anti-apoptotic, and anticancer properties. In this study, a strategy was developed to transform and extract resveratrol from Polygonum cuspidatum on the basis of NADES (natural deep eutectic solvent). In the series of adjustments and optimizations by single-factor experimental, the optimum NADES system (choline chloride to oxalic acid was 1:1) and other experimental conditions were determined, including water content of NADES, solid-liquid ratio, extraction time, extraction temperature and ultrasonic power. At the same time, RSM combined with BBD further optimized the experimental process, the results obtained by RSM optimization showed that the resveratrol yield of 12.31 mg/g was achieved when solid-liquid ratio was 1:50, temperature was 75℃ and time was 80 min. Meantime, the conversion efficiency of polydatin was 96.11 % and the content of resveratrol increased 6-fold higher than that of untreated sample. The kinetic of extraction and thermodynamic analysis were performed at different extraction temperatures to examine the temperature on the impact of the resveratrol extraction from P. cuspidatum. Ethyl acetate was used for back extraction in order to achieve the recycling of solvent and the recovery of resveratrol from NADES. The results showed that ethyl acetate had a good extraction effect and NADES still had a high capacity to convert and extract resveratrol after three cycles. In addition, the extracts exhibited superior antioxidant activity with higher content of recovered resveratrol. This established process can therefore be used to extract and recover resveratrol from plants as an environmental, pollution-free alternative approach.

Introducing photochromic molecules into the active layer of organic field-effect transistors (OFETs) is a direct way to implement a photoresponse nature in OFETs. However, active layer blended photoresponsive transistors based on n-type semiconductors are challenging and rarely studied, which are crucial for multifunctional organic-based logic applications. Herein, we fabricated n-channel photoresponsive OFETs based on a tri-component active layer spin-coated from the mixed solution of an n-type semiconductor (NDI2OD-DTYM2), spiropyran and polystyrene with a weight ratio of 1:1:1. The morphology of the blended films was improved by the introduction of the polymer matrix. Photochromic spiropyran molecules dispersed in the semiconductor layer could switch between the closed-ring state and ionic open-ring state flexibly under the irradiation of different wavelengths of light, and thus change the channel conductivity reversibly and modulate the OFET characteristics. Therefore, under the irradiation of alternate UV and vis light, both the device carrier mobility and current on and off ratio successfully realized a reversible switch.

The present study aimed to investigate the impacts of telmisartan (TEL) on hepatic fibrosis, serum leptin, leptin protein in liver tissue and its mRNA expression level in rats with non-alcoholic fatty liver disease (NAFLD). Male Sprague Dawley rats were randomly divided into the control (N), model (M), polyene phosphatidylcholine (P) and TEL (T) groups. Group M and the intervention groups were given a high-fat diet for 12 weeks to induce NAFLD, followed by 4 weeks of intragastric administration of normal saline (1.0 ml/kg/day), polyene phosphatidylcholine (PPC; 123.1 mg/kg/day) and TEL (8 mg/kg/day). The liver tissue was then assessed for the NAFLD activity score and fibrosis score (FS), and serum biochemistry and leptin levels were determined. Additionally, leptin protein expression levels were examined by western blotting and the expression of leptin mRNA was investigated by reverse transcription-polymerase chain reaction. TEL significantly improved FS in rats (P0.05). TEL reduced serum leptin, leptin protein and its mRNA in the liver tissue of NAFLD rats, and improved the pathological indicators of liver fibrosis.

A highly efficient atom-economic method for the preparation of chiral 3,3'-bis(indolyl)methanes (BIMs) is described. In the promotion of 1 mol % chiral phosphoric acid 3m, structurally divers BIMs with quaternary stereogenic carbon centers are produced in excellent yields and enantioselectivities. Control experiments indicate that the formations of two hydrogen bonds simultaneous between catalyst and substrates are the key factors to obtain good stereoselective outcomes.

A highly efficient alkenylation reaction of arylglyoxals with 3-vinylindoles catalyzed by chiral calcium phosphate is described. Structurally diverse allylic alcohols bearing indole and carbonyl units are prepared in excellent yields, good diastereoselectivities, and high to excellent enantioselectivities. These products are good building blocks for the synthesis of polysubstituted chiral tetrahydrocarbozol-2-ones. The mechanism study indicates that the most likely role of the catalyst is to activate the hydrate of arylglyoxal and control the stereoselectivity via desymmetric coordination.

An efficient asymmetric cyclization reaction of amino-acid-derived isothiocyanates with azodicarboxylates is described. The chiral 1,2,4-triazolines are prepared in good yield (up to 87%) and enantioselectivities (up to 95% ee).

In recent years, organic field-effect transistors (OFETs) with high performance and novel multi-functionalities have attracted considerable attention. Meanwhile, featured with reversible photo-isomerization and the corresponding variation in color, chemical/physical properties, photochromic molecules have been applied in sensors, photo-switches and memories. Incorporation of photochromic molecules to blend in the device functional layers or to modify the interfaces of OFETs is common way to build photo-transistors. In this review, we focus on the recent advantages on the study of photoresponsive transistors involving one of three typical photochromic compounds spiropyran, diarylethene and azobenzene. Three main strategies are demonstrated in detail. Firstly, photochromic molecules are doped in active layers or combined with semiconductor structure thus forming photo-reversible active layers. Secondly, the modification of dielectric layer/active layer interface is mainly carried out by bilayer dielectric. Thirdly, the photo-isomerization of self-assembled monolayer (SAM) on the electrode/active layer interface can reversibly modulate the work functions and charge injection barrier, result in bifunctional OFETs. All in all, the combination of photochromic molecules and OFETs is an efficient way for the fabrication of organic photoelectric devices. Photoresponsive transistors consisted of photochromic molecules are potential candidate for real applications in the future.

Conventional bamboo processing is performed with concentrated alkali. Mild treatments can be done with enzymes or microbes, with considerable environmental benefits. However, the existing commercial enzymes have limited effects on bamboo fibres. Here, we focus our study on a xylanase from Streptomyces sp. FA1, which was isolated from a bamboo retting system. We boosted the xylanase modification of bamboo fibre by means of a cellulase pretreatment. The pretreatment exposes fibre and greatly benefits xylan removal. A high-temperature steam step was found to be better placed after cellulase treatment and before xylanase treatment. Crystallinity of bamboo slightly increased from 46 to 53% after the treatment process, which might be due to the hydrolysis and removal of hemicellulose and amorphous cellulose. The present work gives indications of the best sequence of application of cellulase and xylanase enzymes in bamboo processing.

The highly efficient, regioselective, and enantioselective transfer hydrogenation of α-keto ketimines and reductive amination of diketones by Bronsted acid catalysis is described. A series of chiral α-amino ketones is prepared in high yields (up to >99%), excellent regioselectivities (up to >99:1), and enantioselectivities (up to 98% ee). This method has broad substrate scope.

Iron (Fe) deficiency chlorosis is a yield-limiting problem in citrus production regions with calcareous soils. Physiological and transcriptional analyses of fragrant citrus (Citrus junos Sieb. ex Tanaka) leaves from Fe-sufficient (IS) and Fe-deficient (ID) plants were investigated in this study. The physiological results showed that Fe, potassium, and nitrogen levels decreased by 12, 15, and 41% in ID leaves, respectively. However, zinc and copper levels increased by 49 and 35% in ID leaves, respectively. The chlorophyll (Chl) content, photosynthesis rate, stomatal conductance, and transpiration rate in ID leaves decreased by 55, 33, 38, and 42%, respectively, compared with IS leaves. Moreover, transcriptional profiling analysis showed that genes associated with Chl metabolism, photosynthesis, and nitrogen metabolism were dramatically downregulated by Fe deficiency. The expression of glutamyl-tRNA reductase 1, chlorophyll(ide) b reductase, and geranylgeranyl diphosphate reductase in ID leaves was 0.26–0.37 times that in IS leaves. The expression levels of 16 photosynthesis-related genes were severely downregulated by Fe deficiency. In addition, the transcription levels of nitrate transporter, nitrate reductase, and ferredoxin-nitrite reductase genes in ID leaves were 0.38–0.45 times those in IS leaves. Taken together, these results indicated that the block of Chl biosynthesis, the reduction of photosynthesis, and the repression of nitrogen absorption resulted in the chlorosis symptoms observed in fragrant citrus leaves.

Gastric cancer is the fourth most common malignancy and the third leading cause of cancer‑associated deaths worldwide. It has previously been demonstrated that microRNAs (miRNAs) are actively involved in the pathogenesis of gastric cancer. Therefore, miRNAs have been proposed as promising therapeutic targets in gastric cancer patients. MiR‑744 is aberrantly expressed in different types of human cancer. However, the expression pattern and biological roles of miR‑744 in gastric cancer remain unknown. The present study demonstrated that miR‑744 expression was low in gastric cancer tissues and cell lines. Low expression levels of miR‑744 was significantly correlated with lymph node metastasis, invasive depth and TNM staging in gastric cancer patients. The restoration of miR‑744 expression inhibited cell proliferation and invasion in vitro. Bioinformatic prediction, luciferase reporter assay, reverse transcription‑quantitative polymerase chain reaction and western blot analysis verified that brain‑derived neurotrophic factor (BDNF) is a direct target of miR‑744 in gastric cancer cells. Furthermore, BDNF was upregulated in gastric cancer tissues and inversely correlated with miR‑744 expression. Furthermore, enforced BDNF expression reversed the tumor‑suppressing effects of miR‑744 on the proliferation and invasion of gastric cancer cells, indicating that BDNF is a functional mediator of miR‑744 in gastric cancer. The present study suggests that miR‑744 is a potential prognostic biomarker and treatment target in gastric cancer patients.

This work describes an efficient α-alkylation reaction of α-amino aldehydes with 3-indolylmethanols. In the promotion of catalyst 3f, the target products were obtained in high yields (up to 99%), good diastereoselectivities (up to 88:12), and excellent enantioselectivities (up to 96% ee). The direct alkylation products can be readily converted into other tryptophan derivatives without the loss of stereoselectivities.

The combination of the (1,3-dithiol-2-ylidene)malononitrile (DTYM) and/or (1,3-dithiol-2-ylidene)acetonitrile (DTYA) moieties with naphthalenediimide (NDI) core affords two singly linked NDI-based dimers, (DTYM-NDI-DTYA)2 (D1) and (NDI-DTYA)2 (D2), which both contain a dicyano-substituted vinylogous tetrathiafulvalene (TTF) unit. The synthesis, thermal/optical/electrochemical properties of D1 and D2, and their primary applications in n-channel organic thin film transistors are studied. The results demonstrate that these NDI-fused vinylogous TTFs are excellent electron acceptors, and their further applications are promising.

A simple Bronsted acid catalyzed tandem reaction, including intermolecular nucleophilic addition, substitution and intramolecular cyclization, in a one-pot manner is described. Thirty two 2-indolyl substituted carbazoles are generated in good to excellent yields. Based on this tandem reaction strategy, the poly(1,4-carbazole) is prepared for the first time. Preliminary studies indicate that the poly(1,4-carbazole) has good thermostability and optical properties.

In recent years, organic field-effect transistors (OFETs) with high performance and novel multi-functionalities have attracted considerable attention. Meanwhile, featured with reversible photo-isomerization and the corresponding variation in color, chemical/physical properties, photochromic molecules have been applied in sensors, photo-switches and memories. Incorporation of photochromic molecules to blend in the device functional layers or to modify the interfaces of OFETs is common way to build photo-transistors. In this review, we focus on the recent advantages on the study of photoresponsive transistors involving one of three typical photochromic compounds spiropyran, diarylethene and azobenzene. Three main strategies are demonstrated in detail. Firstly, photochromic molecules are doped in active layers or combined with semiconductor structure thus forming photo-reversible active layers. Secondly, the modification of dielectric layer/active layer interface is mainly carried out by bilayer dielectric. Thirdly, the photo-isomerization of self-assembled monolayer (SAM) on the electrode/active layer interface can reversibly modulate the work functions and charge injection barrier, result in bifunctional OFETs. All in all, the combination of photochromic molecules and OFETs is an efficient way for the fabrication of organic photoelectric devices. Photoresponsive transistors consisted of photochromic molecules are potential candidate for real applications in the future.

The 3-vinyl indole is used as a nucleophile to react with aromatic and aliphatic imines. Chiral 3-substituted indoles bearing multiple functional groups are produced with up to 99% yield, a 98:2 E/Z ratio, and 97% ee. A possible mechanism is proposed to explain the observed stereoselectivities. This strategy provides an efficient way for the preparation of novel chiral 3-substituted indoles.

Software process improvement (SPI) using the RUP is a persistent and iterative process which needs suitable methods for tailoring and measuring. The paper provides a method to tailor the RUP using the Zachman framework as an aid. In the method the RUP artifact matrix based on the Zachman framework represents tailoring result of artifacts vs. roles and the fulfilling rules of the artifact matrix represent the dependency relationship of artifacts of each cell. In addition the paper introduces two measurement models for measuring the performance of the development process to assist SPI in an iterative mode.

Bamboo processing was performed with commercial cellulase. The properties of cellulase and the effect of high temperature pretreatment on cellulase hydrolysis of bamboo were investigated. Results indicated that cellulase hydrolysis performed fast and dramatically within 30 minutes, and then gradually reached its balance. It was found that pretreatment played an active role in cellulase processing, which enhanced the saccharification of bamboo and benefited high-molecular-weight lignin degradation and removal. Additionally, a better performance of bamboo processing was achieved under the cellulase concentration of 15IU in total reaction system of 100 ml at 50?C, pH 4.8, together with the high temperature pretreatment of 120?C for 15 minutes.

The method of analyzing capability and verifying correctness for workflow process is divided in static check and dynamic simulation. The focus of the paper is to test and analyze workflow process by means of dynamic simulation, further to confirm that a process will do appropriate things at appropriate time by appropriate resources. The paper will research some key issues in process simulation——setting up simulation environment, the algorithm for arranging events in a queue based on path coverage rule, analyzing simulation results. It adopts interactive and non-interactive means and makes use of white-box and black-box methods to test workflow process on the base of high coverage rate. At last the classification, distribution and trend of process defects will be presented by various simulation results.

This work describes an efficient α-alkylation reaction of α-amino aldehydes with 3-indolylmethanols. In the promotion of catalyst 3f, the target products were obtained in high yields (up to 99%), good diastereoselectivities (up to 88:12), and excellent enantioselectivities (up to 96% ee). The direct alkylation products can be readily converted into other tryptophan derivatives without the loss of stereoselectivities.

An efficient aldol reaction of indole-3-carbaldehydes with ketones is described. O-TBS-protected l -threonine promoted the aldol addition of ketones to indole-3-carbaldehydes affording 3-indolylmethanols with good to excellent yields and diastereoselectivities, and excellent enantioselectivities.

Native cellulose can be disintegrated into substructures with nano-size dimension through electronspinning. Typically, the most common source material available for cellulose nano-fiber production is wood. More attempts are employed to find new suitable resources to produce nano-cellulose at present. Bamboo boasts the abundant resource in China and possesses fast-growing, anti-bacterial, anti-UV, aroma absorbance properties as well as superior physical and mechanical characters. Cellulose is the main constituent in bamboo, which shows great potential to be the ideal source for producing cellulose nano-fiber. Traditional method for bamboo cellulose extraction needs the use of high concentrated alkaline. Such process causes severe environment problems. Therefore, study on alternative green technologies is inevitable. In this work, self-produced xylanase was applied to hydrolyze bamboo noncellulosic substances. Results indicated that such xylanase from Streptomyces sp. FA1 isolated from bamboo retting system showed broad pH range for xylan hydrolysis, which presented activity of 180 U/mL and 270 U/mL under preferred pH5.5 and pH7, respectively. Three pretreatment methods (including high temperature, ultrasonic generator and supersonic cleaner) were employed to enhance the bamboo processing, among which, xylanase hydrolysis on high temperature pretreated (120°C, 60 min) bamboo showed the most obvious effect. Thermogravimetric test represented that the weight loss of xylanase hydrolysis on high-temperature pretreated sample was higher than that of original sample, which might be attributed to the decomposition of hemi-cellulose and part of cellulose. This study establishes a base for future studies to develop enzymatic hydrolysis of bamboo noncellulosic materials, making them suitable for cellulose nano-fiber producing.

Various differently substituted tryptophan derivatives are prepared with up to 98% enantiomeric excess.

An efficient aldol reaction of indole-3-carbaldehydes with ketones is described. O-TBS-protected l -threonine promoted the aldol addition of ketones to indole-3-carbaldehydes affording 3-indolylmethanols with good to excellent yields and diastereoselectivities, and excellent enantioselectivities.

Detecting small breast tumors is difficult for conventional ultrasound. The goal of this study was to assess the value of ultrasound elastography in characterizing small breast tumors and to compare its sensitivity, specificity and accuracy with conventional ultrasound.A total of 308 breast tumors less than 2 cm in size from 283 in-hospital patients examined with both conventional ultrasound and ultrasound elastography were retrospectively analyzed. The results were compared to surgical pathology.There were 104 malignant and 204 benign lesions. The sensitivities of sonography and sonoelastography were similar (P0.05), and the sensitivity of the two modalities combined improved remarkably to 97.1%. The mean elastic score of malignant and benign tumors less than 2 cm were 3.76 ± 1.01 and 1.73 ± 0.99, respectively (P0.05), and the mean elastic score of the false-negative lesions on conventional ultrasound was 3.61 ± 1.14.Ultrasound elastography in combination with conventional ultrasound can improve the sensitivity for detecting small breast tumors. It is also valuable in detecting small malignant tumors which are difficult to diagnose with conventional ultrasound. Ultrasound elastography can be a useful adjunct to conventional ultrasound in diagnosing small breast tumors.

To study the chemical constituents of Rhizoma Imperatae and their anti-complementary activity.By the hemolysis test, the petroleum extraction, ethyl acetate extraction, n-butanol extraction and the water extraction was tested for anti-complementary activity. Compounds were isolated and purified by silica gel column chromatography, Sephadex LH-20 and reversed-phase column chromatography. The structures were identified by the various spectroscopic data of ESI-MS, 1H-NMR, 13C-NMR. The compounds were evaluated for anti-complementary activity in vitro.The petroleum extraction, ethyl acetate extraction showed significant anti-complementary activity. Ten compounds were isolated from the petroleum and EtOAc soluble fractions and identified as cylindrin (1), arundoin (2), friedelin (3), beta-sitosterol (4), siderin (5), ethyl p-hydroxybenzoate (6), 5-methoxyflavone (7), vanillic acid (8), trans-p-coumaric acid (9), 5-hydroxymethylfurfural (10).Compounds 6, 7, 8, and 10 are isolated from the genus for the first time, and compounds 3, 8 and 9 inhibited the complement system towards the classical pathway.

To study the alkaloids from Armeniaca mume Sieb.The alkaloids were extracted with chloroform from 80% alcoholic extract and concentrated. Then they were transferred into aqueous solution and absorbed by macroporous cation exchange resin. The concentrated total eluent was extracted with chloroform. The alkaloids were purified by recrystallization with petroleum ether and sublimation. Then they were determined by Fourier Transform Infrared spectroscopy, Mass spectrometry and Nuclear magnetic resonance etc methods.Two alkaloids were separated and their structures were elucidated as 2,2,6,6-tetramethyl-4-piperidone and tert-butylurea on the basis of spectral evidence.They are new alkaloids from A. mume.