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In this paper, utilizing the purified flue gas desulfurization (FGD) gypsum as raw materials to prepare calcium sulfate whisker (CSW) by hydrothermal method, the effects of the dosage of crystal modifier, reaction temperature, pH, etc. on the crystal morphology of CSW were discussed. The results show that the purified FGD gypsum can replace high-quality natural gypsum for the preparation of the CSW with excellent quality. The dosage of crystal modifier (K2SO4) and reaction temperature have a significant effect on the morphology and aspect ratio of CSW, while pH and reaction time have a minor effect. When the dosage of K2SO4 is 3 wt%, pH is adjusted to 2 and the solution is reacted at 130 °C for 60 min, CSW with excellent quality can be obtained.

Two novel diterpene dimers with a bismagdalenic acid skeleton, bisyinshanic acids A and B (1 and 2, resp.), along with eight known diterpenoids (310), were isolated from the roots of Euphorbia yinshanica. Their structures were elucidated on the basis of spectroscopic evidence.

Streptomyces are beneficial soil microorganisms and potential candidates for biocontrol agents against soilborne pathogenic fungi of cucurbit plants. Extracellular enzymes such as cellulase, chitinase and glucanase produced by Streptomyces are important components of actinomycete-fungus antagonism. This study aimed to investigate the influence on extracellular enzymes production and fungal mycelia degradation by antagonistic Streptomyces of mycelia preparation of pathogenic fungi (MPPF) of cucurbit plants. The results showed that the antagonistic Streptomyces displayed high extracellular enzyme activities to varying degrees when MPPF was used as the sole carbon source. The MPPF from Fusarium proliferatum, Fusarium oxysporum f. sp. niveum and Alternaria tenuissima were the most effective carbon sources in enhancing the cellulase activity of Streptomyces globisporus C7, Streptomyces globisporus subsp. globisporus C28 and Streptomyces kanamyceticus C49, respectively. S. globisporus subsp. globisporus C28, Streptomyces pactum A12 and S. kanamyceticus C49 cultured in the medium containing MPPF from Fusarium equiseti showed the highest chitinase activity (12.35, 12.50 and 15.06 U, respectively) of all the MPPF treatments. Glucanase activity of Streptomyces carnosus A11 was enhanced greatly (9.26 U) when MPPF from A. tenuissima was used as the sole carbon source. A hyphal intertwining and degradation phenomenon was observed when the antagonistic Streptomyces came across the pathogenic fungal mycelia, which was due to a synergistic effect of the extracellular enzymes produced by the antagonistic Streptomyces.

WSN (Wireless Sensor Networks) has been considered as one of the very promising technologies for the implementation of smart grid (SG). On the other hand, with recent advances in Cognitive Radio (CR) technology, it is possible to apply the Dynamic Spectrum Access (DSA) model in WSN to get access to less congested spectrum, possibly with better propagation characteristics. In this paper we investigate the application of WSN in smart grid and the structure of traditional WSN etc. For smart grid utility, a novel environment-adaptive and cross-layer architecture of CR-based WSN is proposed. Furthermore, the design methods, general characteristics and functions of every layer or every module are described and discussed.

The diagnostic value of combining glypican-3 (GPC3) and CD34 staining for small nodules in liver biopsy specimens has not been evaluated. In this study, 201 thin-core biopsy specimens were assessed using GPC3 and CD34 immunochemical staining, including 33 cirrhotic regenerative nodules, 31 high-grade dysplastic nodules, 70 hepatocellular carcinomas (HCCs) with nodules 3 cm or smaller, and 67 HCCs with nodules larger than 3 cm. The results showed that the accuracy of GPC3 staining (90.3%) among liver nodules 3 cm or smaller was better than its use among all nodules (P = .045). Furthermore, the positive expression rate of costaining was significantly greater than that observed for GPC3 or CD34 single staining (P < .001 and P = .002, respectively).These data demonstrate that GPC3 staining is more accurate for the diagnosis of HCC on thin-core biopsy specimens in nodules 3 cm or smaller compared with its use in all nodules, while GPC3 and CD34 costaining has better diagnostic value than does single staining.

To reduce the coal mining risk, drainage of methane with drills and hydraulic fracture has been put in practice. In the paper, an advanced damage propagation model of brittle fracture is studied based on mode I crack. The localization band of damage is inducted, and the modal of localization of damage around crack-tip is established using fracture and damage mechanics. Besides, the stress distribution in localization of damage is assumed as obeying a quadratic function, thus the stress field around the crack is obtained, and the calculation formula of crack length is presented, which can provide reference for mine production.

To solve the irregular, poor efficiency and lowly reusable of resource, a structured framework based on the course of e-Learning is proposed. The concept knowledge and assisted learning knowledge are combined with course architecture. Based on this framework, course ontology is built according to the method of software engineering and the idea of reusable is adapted. The class hierarchy and the relationship between class are analyzed, and the course of computer network is combined as an example to create an instance.

Drug delivery systems for cancer therapy usually need to be sterically stabilized by a poly(ethylene glycol) (PEG) layer during blood circulation to minimize nonspecific interactions with serum components. However, PEGylation significantly reduces cellular uptake of the delivery systems after they accumulate at the tumor site, which markedly impairs the in vivo antitumor efficiency. Here, we develop a ternary small interfering RNA (siRNA) delivery system with tumor acidity-activated sheddable PEG layer to overcome the challenge. The sheddable nanoparticle is fabricated by introducing a tumor acidity-responsive PEGylated anionic polymer to the surface of positively charged polycation/siRNA complexes via electrostatic interaction. We show clear evidence that introducing the PEGylated anionic polymer to the surface of a nanoparticle markedly reduces its nonspecific interactions with protein. We further demonstrate that the nanoparticle is capable of deshielding the PEG layer at the slightly acidic tumor extracellular microenvironment to facilitate the delivery of siRNA to the tumor cells after accumulation at the tumor site. Accordingly, this promotes the RNA-interfering efficiencies and enhances the inhibition of tumor growth. Such delivery system with the ability to deshield the PEG layer at the target tissues has remarkable potential in cancer therapy.

Efficient delivery of therapeutics into tumor cells to increase the intracellular drug concentration is a major challenge for cancer therapy due to drug resistance and inefficient cellular uptake. Herein, we have designed a tailor-made dual pH-sensitive polymer-drug conjugate nanoparticulate system to overcome the challenges. The nanoparticle is capable of reversing its surface charge from negative to positive at tumor extracellular pH (∼6.8) to facilitate cell internalization. Subsequently, the significantly increased acidity in subcellular compartments such as the endosome (∼5.0) further promotes doxorubicin release from the endocytosed drug carriers. This dual pH-sensitive nanoparticle has showed enhanced cytotoxicity in drug-resistant cancer stem cells, indicating its great potential for cancer therapy.

The synthesis of thermo-responsive hydrogels poly(N-isopropylacrylamide )(PNIPAm) by frontal polymerization (FP) was carried out in four mixed solvents, i.e. dimethylsulfoxide (DMSO) mixing with water, ethanol, tetrahydrofuran (THF) and acetone, respectively. The influences of mixed solvent on frontal parameters, pore morphologies, swelling behavior of PNIPAm hydrogels were investigated. The pore of PNIPAm hydrogel synthesized in THF/DMSO was observed a big honeycomb cells, others were channel-like cells. Furthermore, the sample obtained in THF/DMSO had higher swelling ratio as compared to others, and the one synthesized in Water/DMSO showed the lowest. Above results indicated that fine-tuned poly(N-isopropylacrylamide) hydrogels can be prepared in short time and with easy protocol by adjusting mixed solvents in frontal polymerization process.

CeO2nano-sized crystalline powders were prepared by sol-gel combustion method from ammonium cerium nitrate and citric acid, and the dependences of the particle size of synthesized powder on the precursor gel were investigated. The precursor gels and the synthesized powders were characterized by field emission scanning electron microscopy (FE-SEM) and X-ray scattering (XRD). The colloid particle with nanometer size was firstly observed by FE-SEM, and its size variation had the same tendency as that of CeO2powders with the varying of the ratio of metal ions to citric acid. Furthermore, the probable reasons for the effect of gel structure on properties of nano-sized ceria powders prepared by sol-gel combustion were explained.

A new quadrilateral arrangements for landmark Multi Dimensional Scaling (LMDS) is proposed in this paper. The proposed strategy for choosing the landmark points improved the accuracy which was the main flaw of LMDS. After employing this arrangement, the improved quadrilateral landmarks MDS (QLMDS) preserves the computational efficiency of LMDS and uses quadrilateral arrangement of landmark points to obtain a higher accuracy. To compare the accuracy and computational efficiency of QLMDS with classical Multi Dimensional Scaling (CMDS) and then the accuracy of QLMDS with LMDS, several simulations are presented. The results, apparently, show that QLMDS is as fast as LMDS, but with a higher accuracy which makes it a better choice than CMDS and LMDS.

The instability of permafrost directly results of the differential settlement of railway subgrade, which brought a great threat to the security operation of railway. In order to obtain the top-limit (zero-temperature interface) data of permafrost, according to the testing environment and the requirements for and use of different dielectric constant, using ground-penetrating radar (GPR) detection. The experimental results show that the method is accurate and effective, and we can get better material data on the zero-temperature interface.

The analysis on fault characteristic of Distribution Electronic Power Transformer (D-EPT) can help design its operation and protection scheme, hence improve the reliability of the D-EPT as well as the distribution power grid. The DC pole-to-pole short-circuit fault at DC-Link is analyzed with R-L-C resonant mode and free-wheeling mode, and the theoretical analysis on the short-circuit voltage and current is based on several influence factors and relevant system parameters, which indicates that the fault characteristics are related to the configuration, operation and system parameters of D-EPT.

Cyclic phosphoester monomer ethyl ethylene phosphate (EEP) modified poly(ethylenimine) (PEI), denoted as PEI-EEP, was developed for gene delivery. Three PEI-EEP polymers were synthesized and their structures were characterized by 1H and 31P NMR methods. All the PEI-EEP polymers could condense DNA efficiently at N/P ratios higher than 0.5/1. The physiochemical characteristics of PEI-EEP/DNA complexes were analyzed by particle size and zeta potential measurements. The particle sizes of complexes were around 160–250 nm, and their zeta potentials were around 30–45 mV at the N/P ratios ranging from 10/1 to 50/1. In vitro cell viability and transfection ability were evaluated in HEK293 and HeLa cells using PEI as the control. The cytotoxicity of PEI-EEP and PEI-EEP/DNA complexes was lower than that of PEI and its complexes with DNA. The transfection efficiency of PEI-EEP/DNA complexes was correlated to modification degrees with phosphoester. When the modification of phosphoester to PEI was moderate, the PEI-EEP1/DNA and PEI-EEP2/DNA complexes exhibited comparable or even higher transfection ability than PEI/DNA complex at its optimal N/P ratio in the absence of serum. However, transfection efficiency of PEI-EEP3 reduced dramatically. More importantly, the PEI-EEP exhibited higher transfection efficiency in the presence of 10% serum than that without serum. Therefore, PEI-EEP polymers may be attractive vectors for non-viral gene therapy.

Stress facilitates pain perception and sensitizes pain pathways, but the underlying mechanism is still unclear. The purpose of this study was to investigate whether the activation of 5-hydroxytrypt...

Combination of two or more therapeutic strategies with different mechanisms can cooperatively prohibit cancer development. Combination of chemotherapy and small interfering RNA (siRNA)-based therapy represents an example of this approach. Hypothesizing that the chemotherapeutic drug and the siRNA should be simultaneously delivered to the same tumoral cell to exert their synergistic effect, the development of delivery systems that can efficiently encapsulate two drugs and successfully deliver payloads to targeted sites via systemic administration has proven to be challenging. Here, we demonstrate an innovative "two-in-one" micelleplex approach based on micellar nanoparticles of a biodegradable triblock copolymer poly(ethylene glycol)-b-poly(ε-caprolactone)-b-poly(2-aminoethyl ethylene phosphate) to systemically deliver the siRNA and chemotherapeutic drug. We show clear evidence that the micelleplex is capable of delivering siRNA and paclitaxel simultaneously to the same tumoral cells both in vitro and in vivo. We further demonstrate that systemic administration of the micelleplex carrying polo-like kinase 1 (Plk1) specific siRNA and paclitaxel can induce a synergistic tumor suppression effect in the MDA-MB-435s xenograft murine model, requiring a thousand-fold less paclitaxel than needed for paclitaxel monotherapy delivered by the micelleplex and without activation of the innate immune response or generation of carrier-associated toxicity.

Astilbin, a flavonoid compound, was isolated from the rhizome of

Objective This study was aimed to identify the specific methylation profile in bile specimens of pancreaticobillary diseases for differential diagnosis of malignant biliary stricture. Design and methods In a total of 80 bile specimens from pancreaticobillary diseases, the methylation status of 19 tumor suppressor genes were analyzed by methylation-specific PCR and the methylation index (MI) were compared between the malignant and benign groups. Results Methylation of DKK3, p16, SFRP2, DKK2, NPTX2 and ppENK were more frequently detected in the bile of malignant biliary strictures than benign patients. When setting MI 0.5 as the threshold, this 6-gene panel could distinguish the malignant biliary stricture with a high sensitivity, specificity and accuracy (77.27%, 77.78% and 77.50%, respectively). Conclusion The methylation profile including 6 specific genes in bile may be a promising biomarker for differential diagnosis between malignant and benign biliary strictures.

Reaction of ligand (s)-1 with Li2PdCl4 leads to a chloro-bridged dimer of cyclometallated ferrocenylimine syn-(+)-(Rp,Sc,Rp,Sc)-2 with both planar and central chirality via C–H activation. Treatment compound 2 with PPh3 afford the stable cyclometallated compound (+)-(Rp,Sc)-3 in excellent yields (92%). Both complexes were fully characterized by IR, 1H NMR and specific rotations. X-ray analysis revealed that the absolute planar chirality at the ferrocenyl moiety and the central chirality at the C atom in syn-(+)-(Rp,Sc,Rp,Sc)-2 and (+)-(Rp,Sc)-3 are both retained during the μ-Cl-bridges cleavage step. In addition, compound 3 possess 1D helical chain structures with 21 screw axes along the b-direction.

The persistence of covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) in hepatocytes plays a key role in viral persistence and resistance to therapy. Therefore, quantitative cccDNA measurement is of clinical importance for evaluating the efficacy of antiviral drugs, selecting an appropriate treatment strategy, and predicting the prognosis. Current established methods for measurement of cccDNA need further improvement. A modified method was developed using digestion with restriction endonucleases that do not recognize sites in the HBV DNA and plasmid-safe ATP-dependent DNase (PSAD), and using a cccDNA-specific primer set in a real-time PCR reaction. The cccDNA-specific primer has a similar amplification efficiency as a commercial kit. Treatment of samples with restriction endonuclease followed by PSAD digestion increased significantly the specificity of a cccDNA-selective primer set compared with other treatments (P

Two new 7-dehydrobrefeldin A acids, (2E,4R*)-4-hydroxy-4-[(1R*,2S*)-4-oxo-2-[(1E)-6-oxohept-1en-1-yl]-4-oxocyclopentyl]but-2enoic acid (3) and (2E,4R*)-4-hydroxy-4-[(1R*,2S*)-2-[(1E,6S*)-6-hydroxy-hept-1-en-1-yl]-4-oxocyclopentyl}but-2-enoic acid (4), were isolated from the endophytic fungal strain Cyclindrocarpon obtusisporum (COOKE & HARKNESS) WOLLENW. of Trewia nudiflora, together with two known compounds, 7-dehydrobrefeldin A (2) and brefeldin A (1). Their structures were determined on the basis of extensive 1D- and 2D-NMR-spectral analysis.

A new flavone C-glycoside, isovitexin 6 ''-O-E-p-coumarate (1) and two known flavonoid glycosides-quercetin 3-O-beta-D-glucuronopyranoside (2) and isoorientin (3)were isolated from an ethanol extract of aerial parts of Clematis rehderiana. Their structures were determined by spectroscopic methods. The antioxidant effects of the two flavone C-glycosides were evaluated by both the MTT and DPPH assays. Compound 1 showed potent activities against H(2)O(2)-induced impairment in PC12 cells within the concentration range tested, whereas compound 3 scavenged DPPH radical strongly, with an IC(50) value of 13.5 mu M.

An efficient and safe delivery system for small interfering RNA (siRNA) is required for clinical application of RNA interfering therapeutics. Polyethyleneimine (PEI)-capped gold nanoparticles (AuNPs) are successfully manufactured using PEI as the reductant and stabilizer, which bind siRNA at an appropriate weight ratio by electrostatic interaction and result in well-dispersed nanoparticles with uniform structure and narrow size distribution. With siRNA binding, PEI-capped AuNPs induce more significant and enhanced reduction in targeted green fluorescent protein expression in MDA-MB-435s cells, though more internalized PEI/siRNA complexes in cells are evidenced by confocal laser scanning microscopy observation and fluorescence-activated cell sorting analyses. PEI-capped AuNPs/siRNA targeting endogenous cell-cycle kinase, an oncogene polo-like kinase 1 (PLK1), display significant gene expression knockdown and induce enhanced cell apoptosis, whereas it is not obvious when the cells are treated with PLK1 siRNA using PEI as the carrier. Without exhibiting cellular toxicity, PEI-capped AuNPs appear to be suitable as a potential carrier for intracellular siRNA delivery.

The N-5-ferrocenylisophthalic amino acid methyl esters derivatives 4a–f were prepared by direct condensation of 5-ferrocenylisophthalic dichloride to the corresponding amino acid methyl esters. The compounds were fully characterized by a range of NMR spectroscopic techniques, mass spectrometry (ESI-MS) and cyclovoltammetry (CV). The cyclovoltammetric behavior of 4a–f showed one pair of well-defined and stable redox waves in potential range of 0.0–0.9 V at the GC electrode, which were attributed to the Fc/Fc+ redox process. Electrochemical investigations of 4a–f demonstrated that addition of H2PO4– resulted in large shifts of the respective Fc/Fc+ couple to more negative potentials (ca. 39–68 mV), which suggests that compounds 4a–f have good abilities in recognizing H2PO4–. Moreover, 1H NMR spectroscopic anion titration studies of 4c and 4e strongly suggest the contributions of the amide and Ar–H protons as the important hydrogen donors in anion binding.

Four new compounds named (3E,7Z,11E)-19-hydroxycasba-3,7,11-trien-5-one (1), 6 alpha-hydroxy-10 beta-methoxy-7 alpha,8 alpha-epoxy-5-oxocasbane-20,10-olide (2), 15 alpha-hydroxylup-20(29)-en-3-one (3), and (2R,4aR,8aR)-3,4,4a,8a-tetrahydro-4a-hydroxy-2,6,7,8a-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-chromene-5,8-dione (4) were isolated from the MeOH extracts of the aerial parts of Ricinus communis L. by chromatographic methods. Their structures were elucidated by extensive spectroscopic experiments.

Field cancerization currently described the theory of tumorigenesis and, until now, has been described in almost all organ systems except in liver. For this reason, we explore the presence of field cancerization in liver and its underlying clinical implication in hepatocellular carcinoma (HCC). In our study, methylation profile of HCC and surgically resected margin (SRM) were established by methylation-specific PCR. Liver cirrhosis (LC), chronic hepatitis and normal liver were treated in the same way as the background control. The correlation analysis among the methylation profile of HCC, SRM and clinicopathological data of HCC patients was made respectively. Our results showed that methylation abnormities related to HCC, but not background disease existed in histologically negative SRM. Monoclonal and polyclonal models may coexist in field cancerization in liver. Patients with RIZ1 methylation in SRM had a shorter disease free survival. The local recurrence trend of early and later recurrence in HCC is potentially related to a second field tumor. From these results, we can suggest that field cancerization exists in liver. The study of field cancerization in liver plays an important role in hepatocarcinogenesis. Second field tumor derived form field cancerization may have important implications in HCC prognosis assessment that is worthy of further study.

A new anti-inflammatory spirovetivane-type sesquiterpenoid, designated as 1,10-didehydrolubimin (1) and thirteen known compounds (2 - 14) were isolated from the whole plants of the ‘Yi’ ethnomedicinal plant Incarvillea arguta. Their structures were established based on spectral methods and by comparison of the spectral data with those reported previously. Compound 1 exhibited significant inhibitory effects on Cox-1 and Cox-2 and a negative effect against 5-Lox at the concentration of 100 μM.

Four new 11-noriridoids named scholareins A-D (1-4), along with three known derivatives, isoboonein (5). alyxialactone (6). and loganin (7), were isolated from EtOH extracts of the bark of Alstonia scholaris bv chromatographic methods. Their structures were identified by extensive mass-spectrometric and spectroscopic (especially 2D-NMR) experiments.

A novel amphiphilic and cationic triblock copolymer consisting of monomethoxy poly(ethylene glycol), poly(epsilon-caprolactone) (PCL) and poly(2-aminoethyl ethylene phosphate) denoted as mPEG(45)-b-PCL(100)-b-PPEEA(12) was designed and synthesized for siRNA delivery. The copolymers were well characterized by (1)H NMR spectroscopy and gel permeation chromatography. Micelle nanoparticles' (MNPs) formation of this amphiphilic copolymer in aqueous solution was studied by dynamic light scattering, transmission electron microscopy and fluorescence technique. MNPs took uniform spherical morphology with zeta potential of around 45 mV and were stabilized by hydrophobic-hydrophobic interaction in the PCL core, exhibiting the critical micelle concentration at 2.7 x 10(-3) mg/mL. Such MNPs allowed siRNA loading post nanoparticle formation without change in uniformity. The average diameter of nanoparticles after siRNA binding ranged from 98 to 125 nm depending on N/P ratios. The siRNA loaded nanoparticles can be effectively internalized and subsequently release siRNA in HEK293 cells, resulting in significant gene knockdown activities, which was demonstrated by delivering two siRNAs targeting green fluorescence protein (GFP). It effectively silenced GFP expression in 40-70% GFP-expressed HEK293 cells and it was observed that higher N/P ratio resulted in more effective silence which was likely due to better cell internalization at higher N/P ratio. MTT assay demonstrated that neither MNPs themselves nor siRNA loaded MNPs showed cytotoxicity even at high concentrations. Such cationic MNPs made from biocompatible and biodegradable polymers are promising for siRNA delivery.

Novel biodegradable amphiphilic ABC 3-miktoarm star terpolymers composed of poly(e-caprolactone) (PCL), monomethoxy poly(ethylene glycol) (MPEG), and polyphosphoester (PPE) were synthesized by a combination of ring-opening polymerization and “click” chemistry. MPEG was first end-capped by epoxide ring, which was opened by sodium azide in the presence of ammonium chloride to give modified MPEG bearing reactive azide and hydroxyl groups (MPEG(−OH,−N3)). “Click” chemistry was then applied to conjugate α-propargyl-ω-acetyl-poly(e-caprolactone) and MPEG(−OH,−N3), resulting in a diblock copolymer of MPEG and PCL with reactive hydroxyl groups at the junction point (MPEG(−OH)-b-PCL), which further initiated ring-opening polymerization of 2-ethoxy-2-oxo-1,3,2-dioxaphospholane (EEP) under the catalytic action of stannous octoate to obtain the desired well-defined (MPEG)(PCL)(PEEP) 3-miktoarm star terpolymers. Such terpolymers and their intermediates were characterized by 1H NMR, FT-IR, and gel permeation chromatogr...

A detailed investigation of the basic fraction of a CO(2) extract of ambrette seeds (Abelmoschus moschatus) revealed a total of 58 nitrogen-containing compounds. The identification of these compounds was carried out by GC-MS and NMR. All the identified nitrogen-containing compounds are reported here for the first time in ambrette seeds. Among these are 27 pyrazine derivatives and 12 pyridines, including the tentative identification of four new natural compounds, 1-(6-ethyl-3-hydroxypyridin-2-yl)ethanone (1), 1-(3-hydroxy-5,6-dimethylpyridin-2-yl)ethanone (2), 1-(3-hydroxy-6-methylpyridin-2-yl)ethanone (3), and 1-(3-hydroxy-5-methylpyridin-2-yl)ethanone (4). The odor of the basic fraction was assumed to be due to these pyrazines and pyridines and also the presence of seven thiazoles. The odors described suggest that these N-compounds contribute to what is described in perfumery terms as the "natural and rounded" character of the ambrette extract.

Two new oleanane-type triterpenoids, 13,28-epoxy-23-hydroxy-11-oleanene-3-one (1) and 13,28- epoxy-21β ,23-dihydroxy-11-oleanene-3-one (2), along with seven known compounds, have been isolated from the aerial parts of Buddleja asiatica Lour. All structures were elucidated by spectroscopic techniques (NMR, MS, UV, and IR).

Most of the coal reservoirs in China are of low-permeability, so hydraulic fracturing is widely used to improve the permeability in the extraction of gas by ground drilling. The ground stress around the well was analyzed by using theory of elasticity. The pressure when the well fractured is formulated and the effect of ground stress on pressure is discussed. The effect of ground-stress-differences on hydraulic fracturing was analyzed by using the numerical software RFPA 2D -Flow in reference to the tectonic stress in Jincheng coal area. The results show that: 1) the position where initial fracture appears is random and fracture branches emerge when the fractures expand if ground stresses in any two directions within a horizontal plane are equal; 2) otherwise, the fractures expand in general along the direction of maximum ground stress and the critical pressure decreases with increasing ground-stress-differences and 3) the preferred well-disposition pattern is diamond shaped. The preferred well spacing is 250 m × 300 m. This study can provide a reference for the design of wells.

A principal goal of cancer nanomedicine is to deliver therapeutics effectively to cancer cells within solid tumors. However, there are a series of biological barriers that impede nanomedicine from reaching target cells. Here, we report a stimuli-responsive clustered nanoparticle to systematically overcome these multiple barriers by sequentially responding to the endogenous attributes of the tumor microenvironment. The smart polymeric clustered nanoparticle (iCluster) has an initial size of ∼100 nm, which is favorable for long blood circulation and high propensity of extravasation through tumor vascular fenestrations. Once iCluster accumulates at tumor sites, the intrinsic tumor extracellular acidity would trigger the discharge of platinum prodrug-conjugated poly(amidoamine) dendrimers (diameter ∼5 nm). Such a structural alteration greatly facilitates tumor penetration and cell internalization of the therapeutics. The internalized dendrimer prodrugs are further reduced intracellularly to release cisplatin to kill cancer cells. The superior in vivo antitumor activities of iCluster are validated in varying intractable tumor models including poorly permeable pancreatic cancer, drug-resistant cancer, and metastatic cancer, demonstrating its versatility and broad applicability.

It is known that there are two mechanisms for localizing a bulk fermion on a brane, one is the well-known Yukawa coupling and the other is the new coupling proposed in [Phys. Rev. D 89, 086001 (2014)]. In this paper, we investigate localization and resonance spectrum of a bulk fermion on the same branes with the two localization mechanisms. It is found that both the two mechanisms can result in a volcano-like effective potential of the fermion Kaluza-Klein modes. The left-chiral fermion zero mode can be localized on the brane and there exist some discrete massive fermion Kaluza-Klein modes that quasilocalized on the brane (also called fermion resonances). The number of the fermion resonances increases linearly with the coupling parameter., 14 pages, 18 figures

Background: Heavy drinking can increase heart rate and blood glucose, induce hypoxic tolerance, impair brain cognitive functions, and alter gene expressions. These phenomena may occur even in response to small dose of ethanol exposure or during its withdrawal. Objectives: To evaluate whether persistent low concentrations of ethanol exposure affect organism function and the gene expressions of ion channels. Methods: Daphnids were randomized to receive placebo 300 min, 2 mM ethanol 300 min, or 2 mM ethanol 240 min and then placebo 60 min. Heart rate, glucose levels, phototactic behavior, and hypoxic tolerance were recorded during experiment. At the end of the study, changes in the mRNA levels of ion channel genes were assessed in response to exposure to ethanol using quantitative polymerase chain reaction (PCR) techniques. Results: Heart rate was reversibly increased by ethanol withdrawal and returned to basal levels upon re-exposure to ethanol. Fifteen of 120 ion channel transcripts were affected by persistent ethanol exposure. Neither ethanol withdrawal nor persistent exposures showed an effect on blood glucose, phototactic behavior, or hypoxic tolerance. Conclusions: Small doses of ethanol can increase heart rate and alter gene expression of multiple ion channels in Daphnia pulex. Affected ion channel genes may assist in understanding the mechanism of ethanol adaptation and tolerance.

We address the problem of moving vehicle detection for dynamic traffic environment with moving cameras. The proposed system obtains visual data from cameras mounted on a moving host vehicle. The optical flow method is employed to estimate the movement of the camera and the relative movement of the background. Moving vehicles are detected by difference of velocity to the background movement model.

This paper proposes an autonomous vehicle navigation system based on Hough Transform and fuzzy logic techniques. Hough Transform is used to detect the lane lines and the position of the vehicle in the lane. The vehicle position and the deviation of the proceeding orientation are used to control the steering system. Fuzzy logic control scheme is used for steering the vehicle. The software simulation study validated the proposed system.

Four new tirucallane triterpenoid saponins, named munronosides I-IV (2-5). along with three known triterpenoids, sapelin B (1). melianodiol. and (3 beta)-22,23-epoxytirucall-7-ene-3,24,25-triol, were isolated from the EtOH extract of the whole plants of Munronia delavayi FRANCH by chromatographic methods. On the basis of spectroscopic evidences, the structures of 2-5 were elucidated as (20S,23R,24S)-21,25-epoxy-29-{{O-beta-D-glucopyranosyl-(1 -> 3)-O-[alpha-L-rhamnopyranosyl-(1 -> 6)]-beta-D-glucopyranosyl}oxy}-23,24-dihydroxytirucall-7-ene-3,21-dione (2), (3 beta,20S,23R,24S)-21,25-epoxy-29-{{O-beta-D-glucopyranosyl-(1 -> 3)-O-[alpha-L-rhamnopyranosyl-(1 -> 6)]-beta-D-glucopyranosyl}oxy}-3,23,24-trihydroxytirucall-7-en-21-one (3), (20S,23R,24S)-24-(acetyloxy)-21,25-epoxy-29-{{O-beta-D-glucopyranosyl-(1 -> 3)-O-[alpha-L-rhamnopyranosyl-(1 -> 6)]-beta-D-glucopyranosyl}oxy}-23-hydroxytirucall-7-ene-3,21-dione (4), and (3 beta,20S,23R,24S)-24-(acetyloxy)-21,25-epoxy-29-{{O-beta-D-glucopyranosyl-(1 -> 3)-O-[alpha-L-rhamnopyranosyl-(1 -> 6)]-beta-D-glucopyranosyl}oxy}-3,23-dihydroxytirucall-7-en-21-one (5).

Novel biodegradable hydrogels by photo-cross-linking macromers based on polyphosphoesters and poly(ethylene glycol) (PEG) are reported. Photo-cross-linkable macromers were synthesized by ring-opening polymerization of the cyclic phosphoester monomer 2-(2-oxo-1,3,2-dioxaphospholoyloxy) ethyl methacrylate (OPEMA) using PEG as the initiator and stannous octoate as the catalyst. The macrorners were characterized by H-1 NMR, Fourier transform infrared spectroscopy, and gel permeation chromatography measurements. The content of polyphosphoester in the macromer was controlled by varying the feed ratio of OPEMA to PEG. Hydrogels were fabricated by exposing aqueous solutions of macromers with 0.05% (w/w) photoinitiator to UV light irradiation, and their swelling kinetics as well as degradation behaviors were evaluated. The results demonstrated that cross-linking density and pH values strongly affected the degradation rates. The macromers was compatible to osteoblast cells, not exhibiting significant cytotoxicity up to 0.5 mg/mL. "Live/dead" cell staining assay also demonstrated that a large majority of the osteoblast cells remained viable after encapsulation into the hydrogel constructs, showing their potential as tissue engineering scaffolds.

[structure: see text] A pair of geometrically isomeric monoterpenoid indole alkaloids with a skeleton rearrangement and two additional carbons, named (19,20) E-alstoscholarine (1) and (19,20) Z-alstoscholarine (2), were obtained from the leaf extract of Alstonia scholaris. Their structures were elucidated on the basis of spectroscopic methods and then confirmed by X-ray crystal diffraction. The biogenesis of these compounds was also proposed.

To discuss the relationship between metallic element and disease through determine the elementals in Tibetan Herbal Medicines and Tibetan Medicine Preparations that have obvious effect on hepatobiliary diseases by Synchrotron Radiation X-ray Source, then to reveal the substance foundation of pharmacological action. The results show that all the Tibetan Herbal Medicines used in the experiment have the 9 kinds of metallic elements of potassium(K), calcium(Ca), titanium(Ti), vanadium(V), chromium(Cr), manganese(Mn), ferrum(Fe), zinc(Zn) and lead(Pb), the content of the elements are in the ppb or ppm level though the element constitute and the content have obvious difference. Tibetan Medicine Preparations have another 6 kinds of metallic elements of nickel(Ni), copper(Cu), rubidium(Rb), mercury(Hg), cobalt(Co), gallium(Ga) and 1 kind of nonmetallic elements of arsenic(As) when compare with Herbal Medicines, and the element constitute and the content also have obvious difference. Take advantage of SR-XRF, the test gets the basic data of elements of Tibetan Herbal Medicines and Preparations, supply the scientific support to discuss the interaction of pharmacological mechanism and the metallic elements, and find the suitability of the technique for the metallic elements detection in Tibetan Medicines.

α-HgS is the main component of traditional Chinese medicine cinnabar, while β-HgS is the main component of Tibetan medicine Zuotai. However, there was no comparative study on the dissolution and absorption in gastrointestinal tract and bioaccumulation in organs of mercury in Cinnabar, Zuotai, α-HgS and β-HgS. In this study, the dissolution process of the four compounds in the human gastrointestinal tract was simulated to determine the mercury dissolutions and compare the mercury dissolution of different medicines and the dissolution-promoting capacity of different solutions. To explore the absorption and bioaccumulation of cinnabar and Zuotai in organisms, mice were orally administered with clinical equivalent doses cinnabar and Zuotai. Meanwhile, a group of mice was given α-HgS and β-HgS with the equivalent mercury with cinnabar, while another group was given β-HgS and HgCl2 with the equivalent mercury with Zuotai. The mercury absorption and bioaccumulation capacities of different medicines in mice and their mercury bioaccumulation in different tissues and organs were compared. The experimental results showed a high mercury dissolutions of Zuotai in artificial gastrointestinal fluid, which was followed by β-HgS, cinnabar and α-HgS. As for the mercury absorption and bioaccumulation in mice, HgCl2 was the highest, β-HgS was the next, and a-HgS was slightly higher than cinnabar. The organs with the mercury bioaccumulation from high to low were kidney, liver and brain. This study is close to clinical practices and can provide reference for the clinical safe medication as well as a study model for the safety evaluation on heavy metal-containing medicines by observing the mercury dissolution, absorption, distribution and accumulation of mercury-containing medicines cinnabar and zuotai.

The paper is aimed to search more natural plant antioxidants and further research and develop new medicinal plant resources in Guizhou. The Guizhou special miao medicine "bod zangd dak" was extracted with 60% ethanol. The antioxidant activity of the different polarity components separated from the extract was tested by DPPH method with ascorbic acid as positive control. The results showed that the IC50 of the different polarity components was as following: ascorbic acid (0.033 4 g x L(-1))ethyl acetate components (0.052 3 g x L(-1))total tannins components (0.054 9 g x L(-1))60% ethanol extraction components (0.076 7 g x L(-1))butanol extraction components (0.110 g x L(-1))water-soluble polysaccharides components (0.168 g x L(-1))water extraction components (0.174 g x L(-1))water components after extraction (0.226 g x L(-1))total polysaccharides components (0.645 g x L(-1)). It is concluded that the different polarity components have different free radical scavenging activity and that provides a scientific basis for further search of the active ingredients and the activive mechanism.