Search

Karst caves are widely distributed in southwest China, causing difficulties and disasters for tunnel construction. To better detect the krast caves in front of the tunnels under construction using the transient electromagnetic method, in this paper we propose a 3-D finite element method to simulate the multi-parameter transient electromagnetic response of unfavorable geological bodies in a whole-space. First, the models of vertical water-filled faults, water-filled caves and complex geological bodies in front of the tunnel face are established. The horizontal electric field component and the vertical magnetic field component at different time in the whole-space are researched. Secondly, the electromagnetic response features of the caves with different resistivity, buried depths and scales are studied. We found that the resistivity of the target body is 10 times larger than that of the surrounding rocks, and the anomaly amplitude increases obviously with the growing distance from the target body. The deeper the buried depth, the later the anomaly appears and the smaller the anomaly amplitude. The larger the target size, the longer the transient electromagnetic response delay and the larger the anomaly amplitude. We arranged a measuring line on the tunnel face. The full-time apparent resistivity section shows the position and characteristics of the low-resistivity anomalous body, indicating that the transient electromagnetic method (TEM) has obvious advantages in detecting the low-resistivity body in front of the tunnel face. Finally, the TEM is successfully applied to the advanced detection of a karst tunnel to get the electrical distribution of the surrounding rocks in front of the tunnel face. According to the geological conditions of the excavated tunnel, the validity of the TEM in the tunnel advanced prediction is verified.

Objective: To investigate the efficacy and safety of cold snare endoscopic mucosal resection (CS-EMR) and hot snare endoscopic mucosal resection (HS-EMR) for colorectal polyps with diameters of 6–9...

Simvastatin treatment is cardioprotective in patients undergoing noncoronary artery cardiac surgery. However, the mechanisms by which simvastatin treatment protects the myocardium under these conditions are not fully understood. Seventy patients undergoing noncoronary cardiac surgery, 35 from a simvastatin treatment group and 35 from a control treatment group, were enrolled in our clinical study. Simvastatin (20 mg/d) was administered preoperatively for 5-7 days. Myocardial tissue biopsies were taken before and after surgery. Apoptosis was detected by TUNEL staining. The expressions of Bcl-2 and Bak in myocardial tissue were detected by immunoblotting. The expressions of miRNA and Bcl-2 mRNA were detected by quantitative real-time polymerase chain reaction assays. Cardiomyocytes were isolated from rat and cultured cells. MiR-15a-5p mimic was transfected into cardiomyocytes, and the Bcl-2 was detected by immunoblotting. TUNEL staining showed significantly less myocardial apoptosis in the simvastatin treatment group when compared with the control treatment group. Protein expression of Bcl-2 was increased in the simvastatin treatment group before surgery, and Bak expression was increased in the control treatment group after surgery. Further comparisons showed that Bcl-2/Bak ratios were reduced in the control treatment group but were not significantly changed in the simvastatin treatment group after surgery. Furthermore, microarray assays revealed that miR-15a-5p was significantly decreased by simvastatin treatment. This was validated by quantitative real-time polymerase chain reaction analysis. MiR-15a-5p was predicted to target Bcl-2 mRNA at nucleotide positions 2529-2536. This was validated by luciferase binding assays. Coincident with the change in miR-15a-5p, the mRNA expression of Bcl-2 was increased in the simvastatin treatment group. MiR-15a-5p mimic significantly inhibited Bcl-2 expression in cardiomyocytes. Our findings strongly suggest that simvastatin treatment preoperatively protected the myocardium in patients undergoing noncoronary artery cardiac surgery, at least in part, by inhibiting apoptosis via suppressing miR-15a-5p expression, leading to increasing expression of Bcl-2 and decreasing expression of Bak.

Yan Guo, Hua-Ming Li, Wei-Qin Zhu, Zhen Li Department of Gastroenterology, Hangzhou Third People’s Hospital, Hangzhou, 310009, People’s Republic of ChinaCorrespondence: Yan GuoDepartment of Gastroenterology Hangzhou Third People’s Hospital, No. 38 West Lake Road, Shangcheng District, Hangzhou, 310009, People’s Republic of ChinaTel +86 571 87823158Fax +86 571 87814481Email yanguodr1@163.comObjective: To investigate the role of Helicobacter pylori (HP) eradication in chronic spontaneous urticaria (CSU) treatment.Methods: Retrospective analysis was performed on the clinical data of 522 patients with CSU who underwent a HP breath test in Hangzhou Third People’s Hospital between January 2018 and December 2019. The CSU-HP(+) group consisted of patients with CSU and HP infection, who were treated with antihistamines combined with HP eradication therapy. The CSU-HP(-) group consisted of patients with CSU alone, who were treated with antihistamines. Propensity score matching (PSM) analysis, using the nearest neighbor matching method on a 1:1 basis, was performed to ensure the characteristics of the CSU-HP(+) and CSU-HP(-) groups were similar. Factors, including age, gender, white blood cells, red blood cells, platelets, alanine transaminase, creatinine, immunoglobulin E, and pre-treatment urticaria activity score (UAS), were matched to obtain a balanced cohort of patients in each group. Therapeutic effects were compared after matching. t-tests, &KHgr;2 test, and McNemar’s test were used for comparison between the two groups before and after matching.Results: Patients in the CSU-HP(+) group reported significantly more gastrointestinal symptoms than those in the CSU-HP(-) group. UAS scores in the second week of treatment were significantly different between the two groups. After 3 months, the recurrence rate in the CSU-HP(+) group was lower than in the CSU-HP(-) group.Conclusion: Eradication of HP infection in patients with CSU helps relieve gastrointestinal symptoms, improves the therapeutic effect of CSU within 2 weeks, and reduces the recurrence rate 3 months after treatment.Keywords: chronic urticaria, chronic spontaneous urticaria, Helicobacter pylori, eradication therapy

Introduction: Previous studies showed that high density lipoprotein (HDL) can stimulate angiogenesis. However, the mechanisms by which HDL promotes angiogenesis remains unclear. Hypothesize: HDL may promote angiogenesis by regulating miRNAs expression. Methods: HDL was isolated from healthy subjects. Human umbilical vein endothelial cells (HUVECs) were cultured with vehicle or HDL (100 μg/ml), and the differential miRNAs expression were indentified by miRNA array and verified by qRT-PCR. HUVECs were treated with vehicle or HDL (100 μg/ml) with or without miRNAs mimic, endothelial cells proliferation, migration and tube formation were detected. The production of nitric oxide(NO) was measured. The expression and phosphorylation of endothelial nitric oxide synthase (eNOS) was determined. Results: The miRNAs profile of HDL-treated HUVECs is significantly different from control group. HDL significantly downregulated miR-24-3p expression. HDL significantly promoted HUVECs proliferation, migration and tube formation. HDL also significantly stimulated NO production and up-regulated the expression and phosphorylation of eNOS. However, HDL did not stimulated HUVECs proliferation, migration, tube formation and NO production as well as the expression and phosphorylation of eNOS after pretreated with miR-24-3p mimic. Conclusions: HDL can promote angiogenesis by suppressing miR-24-3p expression.

In the original publication, the affiliation of Min-Hao Li was published incorrectly as below.

Acute pancreatitis is rarely associated with drugs. Acetaminophen overdose is a well-known cause of hepatic toxicity, but drug-induced pancreatitis is rarely reported, especially after mild overdose. A 32-year-old woman presented with nausea and vomiting for 12 h, but no abdominal pain following an overdose of eight Tylenol tablets containing acetaminophen (325 mg acetaminophen per tablet). Laboratory results on admission showed abnormal amylase and lipase levels but completely normal liver function. Magnetic resonance cholangiopancreatography revealed mild swelling of the pancreas without fluid collection around the pancreas. The patient complained of severe abdominal pain five days after admission when attempting to drink water and liquids. Eight days after admission, fluid around the pancreas was observed by computed tomography. The patient was subsequently diagnosed with acetaminophen-induced acute pancreatitis after exclusion of common causes. Routine treatment for pancreatitis and N-acetylcysteine were administered to prevent disease progression. The patient was discharged in good condition.

Objective To report drug-induced oesophageal ulceration in adult patients treated with doxycycline for acne vulgaris. Methods This retrospective case series included data from adult patients treated with oral doxycycline therapy for acne vulgaris, who had presented with oesophageal ulceration at the Third People’s Hospital of Hangzhou between June 2016 and December 2017, and whose diagnosis was confirmed by gastroscopy. Clinicodemographic data were analysed, including symptom onset, endoscopy results, that were assessed for classic features of oesophageal ulceration. Patients were questioned regarding medication intake. Results A total of 12 patients were included (mean age, 23.50 ± 3.20 years), eight (66.67%) of whom were female. Based on history of medication and endoscopic findings, these patients were diagnosed with doxycycline-induced oesophageal ulceration. Most patients were found to have taken the medication at bedtime, just before lying down, and/or with insufficient water. Conclusion Doxycycline may cause oesophageal irritation when not taken with sufficient water, or taken just before lying down to sleep. Prescribing physicians should be aware of these issues, and instruct patients as to the correct method for intake of doxycycline.

Endothelial dysfunction is an early stage of atherosclerosis. We recently have shown that 25-hydroxycholesterol found in atherosclerotic lesions could impair endothelial function and vasodilation by uncoupling and inhibiting endothelial nitric oxide synthase (eNOS). 1-Palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC), the oxidation product of oxidized low-density lipoprotein, is another proinflammatory lipid and has also been found in atherosclerotic lesions. However, whether POVPC promotes atherosclerosis like 25-hydroxycholesterol remains unclear. The purpose of this study was to explore the effects of POVPC on endothelial function and vasodilation. Human umbilical vein endothelial cells (HUVECs) were incubated with POVPC. Endothelial cell proliferation, migration and tube formation were measured. Nitric oxide (NO) production and superoxide anion generation (O2-) were determined. The expression and phosphorylation of endothelial nitric oxide synthase (eNOS), AKT, PKC-βII and P70S6K as well as the association of eNOS and heat shock protein 90 (HSP90) were detected by immunoblotting and immunoprecipitation. Endothelial cell apoptosis was monitored by TUNEL staining. The expression of Bcl-2, Bax, and Cleaved Caspase 3 were detected by immunoblotting. Finally, aortic ring from C57BL6 mice were isolated and treated with POVPC and the endothelium-dependent vasodilation was evaluated. POVPC significantly inhibited HUVECs proliferation, migration, tube formation, decreased NO production but increased O2- generation. POVPC inhibited the phosphorylation of Akt and eNOS at Ser1177, increased activation of PKC-βII, P70S6K and the phosphorylation of eNOS at Thr495, reduced the association of HSP90 with eNOS. Meanwhile, POVPC induced endothelial cell apoptosis by inhibiting Bcl-2 expression, increasing Bax and cleaved caspase-3 expressions as well as caspase-3 activity and impaired endothelium-dependent vasodilation. These data demonstrated that POVPC impaired endothelial function by uncoupling and inhibiting eNOS as well as by inducing endothelial cell apoptosis. Therefore, POVPC may play an important role in the development of atherosclerosis and may be considered as a potential therapeutic target for atherosclerosis.

Increased evidence has showed that normal high density lipoprotein (HDL) could convert to dysfunctional HDL in diseases states including coronary artery disease (CAD), which regulated vascular endothelial cell function differently. Long non-coding RNAs (lncRNAs) play an extensive role in various important biological processes including endothelial cell function. However, whether lncRNAs are involved in the regulation of HDL metabolism and HDL-induced changes of vascular endothelial function remains unclear. Cultured human umbilical vein endothelial cells (HUVECs) were treated with HDL from healthy subjects and patients with CAD and hypercholesterolemia for 24 h, then the cells were collected for lncRNA-Seq and the expressions of lncRNAs, genes and mRNAs were identified. The bioinformatic analysis was used to evaluate the relationship among lncRNAs, encoding genes and miRNAs. HDL from healthy subjects and patients with CAD and hypercholesterolemia leaded to different expressions of lncRNAs, genes and mRNAs, and further analysis suggested that the differentially expressed lncRNAs played an important role in the regulation of vascular endothelial function. Thus, HDL from patients with CAD and hypercholesterolemia could cause abnormal expression of lncRNAs in vascular endothelial cells to affect vascular function.

It remains unclear how to describe the cluster packing pattern quantitatively in glass-forming liquid. Here the atomic structures of Lennard-Jones glass-forming liquid obtained by molecular dynamics simulations are investigated. Cluster deviation degree is proposed to quantitatively descript the disordered degree of cluster distribution. The results show that the cluster mean deviation degree follows a power-law behavior with temperature. The size of the central atom has an impact on the cluster deviation degree. The proposed concept provides a statistical approach to describe the cluster evolution during the glass-forming process and the structural distinction of metallic glasses.

Normal high-density lipoprotein (nHDL) in normal, healthy subjects is able to promote angiogenesis, but the mechanism remains incompletely understood. HDL from patients with coronary artery disease may undergo a variety of oxidative modifications, rendering it dysfunctional; whether the angiogenic effect is mitigated by such dysfunctional HDL (dHDL) is unknown. We hypothesized that dHDL compromises angiogenesis. The angiogenic effects of nHDL and dHDL were assessed using endothelial cell culture, endothelial sprouts from cardiac tissue from C57BL/6 mice, zebrafish model for vascular growth and a model of impaired vascular growth in hypercholesterolemic low-density lipoprotein receptor null(LDLr-/-)mice. MiRNA microarray and proteomic analyses were used to determine the mechanisms. Lipid hydroperoxides were greater in dHDL than in nHDL. While nHDL stimulated angiogenesis, dHDL attenuated these responses. Protein and miRNA profiles in endothelial cells differed between nHDL and dHDL treatments. Moreover, nHDL suppressed miR-24-3p expression to increase vinculin expression resulting in nitric oxide (NO) production, whereas dHDL delivered miR-24-3p to inhibit vinculin expression leading to superoxide anion (O2•-) generation via scavenger receptor class B type 1. Vinculin was required for endothelial nitric oxide synthase (eNOS) expression and activation and modulated the PI3K/AKT/eNOS and ERK1/2 signaling pathways to regulate nHDL- and VEGF-induced angiogenesis. Vinculin overexpression or miR-24-3p inhibition reversed dHDL-impaired angiogenesis. The expressions of vinculin and eNOS and angiogenesis were decreased, but the expression of miR-24-3p and lipid hydroperoxides in HDL were increased in the ischemic lower limbs of hypercholesterolemic LDLr-/- mice. Overexpression of vinculin or miR-24-3p antagomir restored the impaired-angiogenesis in ischemic hypercholesterolemic LDLr-/- mice. Collectively, nHDL stimulated vinculin and eNOS expression to increase NO production by suppressing miR-24-3p to induce angiogenesis, whereas dHDL inhibited vinculin and eNOS expression to enhance O2•- generation by delivering miR-24-3p to impair angiogenesis, and that vinculin and miR-24-3p may be therapeutic targets for dHDL-impaired angiogenesis., Graphical abstract Image 1, Highlights • nHDL and dHDL regulated angiogenesis differently via alterations in vinculin expression. • nHDL suppressed miR-24-3p to increase vinculin expression to stimulate NO production. • dHDL delivered miR-24-3p to inhibit vinculin expression to enhance O2.•- generation. • Vinculin and miR-24-3p may be therapeutic targets for dHDL-impaired angiogenesis. • Cell-free assay may be used to measure the oxidative levels of HDL.

The high incidence of accidents and fatalities in the coal mining industry is often attributed to ineffective training methods. To improve the training quality,virtual reality simulation has applied to improve the effectiveness of the training. This paper presents a VR-based system for coal mining safety training. System can provide the intuitive approach for studying of the safety knowledge, and provide the interactive exercises for learning self-rescue and escape in the disasters. An architecture is proposed for customize new training mission quickly. The requirements of functions in the system have been discussed. The implemented system has proved that virtual reality training has the potential to provide more meaningful and effective training to address the identified safety needs in coal mining industry.

Background We previously demonstrated that endothelial microparticles (EMPs) are increased in mitral valve diseases and impair valvular endothelial cell function. Perioperative systemic inflammation is an important risk factor and complication of cardiac surgery. In this study, we investigate whether EMPs increase in congenital heart diseases to promote inflammation and endothelial dysfunction. Methods The level of plasma EMPs in 20 patients with atrial septal defect (ASD), 23 patients with ventricular septal defect (VSD), and 30 healthy subjects were analyzed by flow cytometry. EMPs generated from human umbilical vascular endothelial cells (HUVECs) were injected into C57BL6 mice, or cultured with HUVECs without or with siRNAs targeting P38 MAPK. The expression and/or phosphorylation of endothelial nitric oxide synthase (eNOS), P38 MAPK, and caveolin-1 in mouse heart and/or in cultured HUVECs were determined. We evaluated generation of nitric oxide (NO) in mouse hearts, and levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in cultured HUVECs and in mice. Results EMPs were significantly elevated in patients with ASD and VSD, especially in those with pulmonary hypertension when compared with controls. EMPs increased caveolin-1 expression and P38 MAPK phosphorylation and decreased eNOS phosphorylation and NO production in mouse hearts. EMPs stimulated P38 MAPK expression, TNF-α and IL-6 production, which were all inhibited by siRNAs targeting P38 MAPK in cultured HUVECs. Conclusions EMPs were increased in adult patients with congenital heart diseases and may contribute to increased inflammation leading to endothelial dysfunction via P38 MAPK-dependent pathways. This novel data provides a potential therapeutic target to address important complications of surgery of congenial heart disease. Electronic supplementary material The online version of this article (doi:10.1186/s12967-016-1087-2) contains supplementary material, which is available to authorized users.

The self-diffusion coefficients in a model liquid and glass forming liquid have been studied as a function of temperature and pressure using the classical molecular dynamics (MD) method. Isothermal–isobaric (NPT) ensemble is carried out in our simulations. Special attention is paid to the glass-forming ability of the rapid-quench method under different pressures. We evaluate (1) glass transition and radial distribution function, (2) temperature dependence of diffusion coefficients in liquid and glass forming liquid, and (3) pressure dependence of diffusion coefficients in glass forming liquid. The simulations show (i) the greater the pressure, the higher the glass-transition temperature, by using the same high enough cooling rate from the melts; (ii) an Arrhenius dependence of diffusion coefficients D with reduced temperature T ⁎ in liquid, that is, ln D ~1/ T ⁎ , and there being a process of slow change in glass forming liquid; (iii) an Arrhenius dependence of diffusion coefficients on pressure in glass forming liquid in the pressure range studied, that is, ln D ~ P ⁎ .

It remains unclear how a cluster packing pattern affects the glass forming ability of bulk metallic glasses. The topological structures of Ti50Cu50 and Ti50Cu45Ni5 metallic glasses obtained by molecular dynamics simulations are compared to investigate the relation between the atomic structure and glass forming ability. The structural analysis shows that the addition of Ni in Ti50Cu50 alloy can significantly change the topological structure. Cluster distribution entropy is proposed to quantitatively descript the disordered degree of cluster distribution. It is shown that the cluster distribution entropy provides a statistical approach for assessing the microstructures of metallic glasses.

采用浸渍法合成ZnO/AgNbO 3 异质结光催化环境净化材料. 利用X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电镜(SEM)、紫外漫反射(DRS)等分析方法对催化剂进行了表征. XRD分析结果表明, Zn的掺杂并未改变本体AgNbO 3 的晶型结构; 随着Zn掺杂量和热处理温度的提高, 异质结光催化剂体系中ZnO晶相结构逐渐出现;同时, XPS结果也说明Zn以ZnO的形式存在. DRS分析说明ZnO的引入有助于提高可见光区的吸收强度. 无论在可见光还是紫外光照射下, 光催化降解亚甲基蓝染料(MB)实验证明ZnO掺杂有利于提高AgNbO3的活性. 当Zn掺杂量为3 wt%, 热处理温度为300℃时, 紫外光照射3 h下MB降解率达到93.5%. 并对ZnO引入后光催化活性提高的机理进行了分析.

Background Surveillance data for rabies in Guangxi Province in China showed that human rabies cases have gradually increased since 1996. Objective To evaluate the epidemiology of rabies at the molecular level and provide suggestions for effective prevention of rabies in Guangxi. Study design Since 2000, 1569 brains from suspected rabid animals were collected from different areas of Guangxi. Rabies virus was isolated from 42 samples. RT-PCR was used to amplify a 455 nucleotide segment of the 3′-terminal of the N gene. The sequencing data from that segment was used for phylogenetic analysis. Results Nucleotide homology comparisons and phylogenetic tree analysis based on this sequence indicated that all the rabies virus isolates from Guangxi belonged to genotype 1 and could be divided into four groups. Groups I, II and IV included 23, 10 and 8 isolates, respectively. These had nucleotide homologies of 97.1–100%, 98.2–100% and 99.1–99.6%, respectively. Only the GXN119 strain belonged to group III. Group I had two group-specific mutations: T90N and E110D. Group II had one group-specific mutation of T42S. Conclusions This study showed that rabies virus isolates from Guangxi have a close genetic relationship and topographical distribution.

A duplex polymerase chain reaction (PCR) was developed and optimized for simultaneous detection and differentiation of Capripoxvirus (CPV) (including goat pox virus and sheep pox virus) and orf virus (ORFV). Two sets of specific oligonucleotide primers were designed and used for CPV and ORFV, respectively. The duplex PCR DNA products, which consisted of fragments of 413 bp for A29L gene of CPV, and 708 bp for P55 gene of ORFV, were visualized by gel electrophoresis. The developed assay was found to be highly specific and sensitive with a detection limit of 1 plaque forming unit (pfu) for both CPV and CPV.

Aiming at the demand for rapid custom development of 3D simulation system for oilfield safety training, this paper designs and implements a 3D simulation engine based on script-driven method, multi-layer structure, pre-defined entity objects and high-level tools such as scene editor, script editor, program loader. A scripting language been defined to control the system's progress, events and operating results. Training teacher can use this engine to edit 3D virtual scenes, set the properties of entity objects, define the logic script of task, and produce a 3D simulation training system without any skills of programming. Through expanding entity class, this engine can be quickly applied to other virtual training areas.

Acetylation of highly stereoregular syndiotactic polystyrene has been accomplished in a heterogeneous process by using carbon disulfide as the dispersing medium, and acetyl chloride and anhydrous aluminium chloride as acetylating agent and catalyst, respectively. The acetylation reaction can be well controlled and carried out to a high degree of acetylation. The resultant polymer was characterized by FTIR and NMR spectroscopy. The incorporation of acetyl groups into syndiotactic polystyrene was found to have an effect on the thermal properties of these new materials. The degree of crystallinity was decreased by the presence of acetyl groups, while the glass transition temperature increased. Copyright © 2004 Society of Chemical Industry

The compatibility, crystallization behavior, and mechanical properties of syndiotactic polystyrene (sPS)/polyester (PET)/potassium salt of sulfonated syndiotactic polystyrene (SsPS-K) were investigated. DMA results showed that all the alloys showed one Tg and the half-peak width of the sPS/PET/SsPS-K alloys became narrower compared with that of sPS/PET alloys, which decreased with an increasing content of the SsPS-K ionomer. The results of DSC showed that the Tm of sPS and PET of the alloys was similar to those of the pure materials and did not change with the content of the SsPS-K ionomer, while the initial crystallization temperature (T0) and crystallization temperature at peak (Tp) increased. The crystallization velocity of PET increased with an increasing content of SsPS-K. The TMA results showed that the alloys could retain the perfect heat proof property of sPS. SEM micrographs showed that the addition of SsPS-K could reduce the PET domain dimension and enhance the adhesion between the PET domains and the matrix. With an increasing content of SsPS-K, the PET domain dimension was reduced continuously and dispersed more evenly. The ternary alloys had better mechanical properties and significantly higher unnotched Izod impact strength than those of the alloys without SsPS-K. When the weight ratio of sPS/PET/SsPS-K was 85/15/4, the impact strength reached a maximum of 11.5 kJ/m2, which was about three times that of pure sPS, and still had a higher tensile strength, flexural strength, and storage modulus, which were 38.8, 54.2, and 1.55 × 104 MPa, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 656–661, 2002

Syndiotactic polystyrene (sPS) and polyamide-6 (PA6) are immiscible and incompatible and have been recognized. In this study, sulfonated syndiotactic polystyrene (SsPS-H) is employed as compatibilizer in the blend of sPS/PA6. During melt blending, the sulfonic acid groups of the SsPS-H can interact strongly with the amine end-groups of PA6 through acid–base interaction. In addition, SsPS-H is miscible with sPS when SsPS-H content is less than 20 wt.%. Therefore, the addition of SsPS-H to sPS/PA6 blends reduces the dispersed phase size and improves the adhesion between the phases. The glass transition temperatures of the PA6 component in the compatibilized blends shift progressively towards higher temperature with the content of SsPS-H-12 increase, indicating enhanced compatibility. On the other hand, the progressive lowering of the melting point and crystallization temperatures of PA6 in the blends with increasing SsPS-H contents compared to the incompatibilized blend, provide some insight into the level of interaction between the PA6 and SsPS-H. The compatibilized blends have significantly higher impact strength than the blends without SsPS-H. The best improvement in the impact strength of the blends was achieved with the content of the SsPS-H (11.9 mol%) about 5 wt.%.

Radical copolymerization of cyclohexene (M1) with N-phenylmaleimide (M2) was carried out with 2,2′-azobis(isobutyronitrile) as an initiator in various solvents at 50°C. The copolymerization of cyclohexene with N-phenylmaleimide in chloroform and dioxane proceeded in a homogeneous system to give an alternating copolymer over a wide range of the comonomer composition in the feed. The initial rate of the copolymerization (Rp) was dependent on the monomer composition and was a maximum at about 65 mol% of N-phenylmaleimide in the feed. A solvent effect on the Rp and the reactivity ratio was investigated in this copolymerization system, i.e., copolymerization in benzene produced a higher Rp than that in chloroform and in dioxane, while in chloroform produced a higher alternating tendency compared with those in benzene and in dioxane (r1=0, r2=0.012 in chloroform; r1=0, r2=0.081 in benzene and r1=0, r2=0.073 in dioxane). The copolymer was characterized by 1H-NMR spectrum.

The copolymerization of cyclohexene (M1) and N-phenylmaleimide (M2) in chloroform with 2,2'-azo-bis(isobutyronitrile) as an initiator was investigated. The copolymerization of N-phenylmaleimide with cyclohexene in chloroform proceeded in a homogeneous system to give an alternating copolymer over a wide range of the comonomer composition in the feed. The kinetic parameters, such as reactivity ratio, overall activity energy and the effect of comonomer composition on the initial copolymerization rate (Rp) were determined. The bimolecular termination of the copolymerization was proved. A kinetic treatment based on the model of mechanism was proposed and used to test the copolymerization of cyclohexene and N-phenylmaleimide and to quantitatively estimate the k21/k12 value.

Syndiotactic polystyrene (sPS) was synthesized with a novel monotitanocene complex of η 5 -pentamethylcyclopentadienyltri-4-methoxyphenoxy titanium [Cp * Ti(OC 6 H 4 OCH 3 ) 3 ] activated by methylaluminoxane (MAO) in different polymerization media, including heptane, toluene, chlorobenzene, and neat styrene. In all cases bulk polymerization produced sPS with the highest activity and molecular weight. Solution polymerization produced much better activity in heptane than in the other solvents. Using a solvent with a higher dipole moment, such as chlorobenzene resulted in lower activity and syndiotacticity because of the stronger coordination of solvent with the Ti(III) active species, which controlled syndiospecific polymerization of styrene. With bulk polymerization at a higher polymerization temperature the Cp*Ti(OC 6 H 4 OCH 3 ) 3 -MAO catalyst produced sPS with high catalytic activity and molecular weight. The external addition of triisobutylaluminum (TIBA) to the Cp * Ti(OC 6 H 4 OCH 3 ) 3 -MAO system catalyzing styrene polymerization led to significant improvement of activity at a lower Al:Ti molar ratio, while the syndiotacticity and molecular weight of the yields were little affected.

It is the first time ionic liquid was applied to gas solvent sublation, which established a new method for separation/enrichment of tetracyclines (TCs) antibiotic based on ionic liquid gas solvent sublation. The optimizing experimental conditions were as follows: the mixture of ionic liquid 1-hexyl-3-methylimidazo lium hexafluorophosphats and ethyl acetate ([Hmim] PF6-EA, phi = 1/0.9) can be used as flotation solvent, Fe(III) ion was as trapping agent, pH of test solution was 7.6, the gas flow rate was 40 mL x min(-1), and the flotation time was 50 min. The complexes of TCs- Fe (III) were pre-concentrated in the [Hmim] PF6-EA layer and this was used to determine analytes by fluorescence method directly. The linear regression equation was F = 246.5c+4.32 (c: microg x 10 mL(-1)), and correlation coefficient was 0.999 1. Recoveries between 94.2% and 100.4% were achieved from surface water and sediment samples in ponder by using this method and the relative standard deviation of 5 microg x mL(-1) TCs for 5 parallel determinations was less than 3.2%. FTIR spectroscopy demonstrated that no chemical (bonding) interactions occurred between the ionic liquid and the complexes functional groups, and the ionic liquid was only solvent. The experimental result indicated that utilizing ionic liquid to float TCs in environmental sample is feasible.

In order to investigate the positive rate of streptococcus suis type 2 and the genes of their suilysin (sly), extracellular protein (epf) and muramidasa-released protein ( mrp) and to understand the antibiotic susceptibility of S. suis type 2.S. suis type 2, isolated from slaughtered healthy pig's tonsil in 10 county area of Guangxi, were identified by Multiplex PCR, and the genes of their sly, epf, mrp and the antimicrobial sensitivity analysis were performed.1105 strains of Streptococcus including 667 strains of S. suis and 33 strains of S. suis type 2 were detected from 1179 samples. In these S. suis type 2 strains, there were 22 strains of sly + mrp + epf+ type,1 strain of sly + mrp + epf - type, 2 strains of sly - mrp + epf + type, 7 strains of sly - mrp + epf - type and 1 strain of sly - mrp - epf- type. When these strains were subjected to be tested with penicillin, eritrocina, vacocin, gentamycin, specti-nomysin, enraxacin, ciprofloxaxin, cephalothin VI, sulfadiazine sodium, cyantin, mycifradin, amikacin and achromcin, some were found to be resistant to but most strains were susceptible to cephalothin VI, penicillin and enraxacin. There were 31, 29 and 27 strains over medium sensitivity, respectively, but 28 and 27 resistant strains to amikacin and achromcin were found.The positive rate of S. suis type 2 in clinical healthy pigs was low (2.8%) and did not show obvious difference between the counties with or without a history of S. suis infection. All the isolated strains were susceptible to cephalothin VI, but most strains were virulent.

We describe the isolation of Laribacter hongkongensis in Hangzhou City, People's Republic of China. One strain of bacterium, named LHHZ242, had many of the same phenotypic and genotypic characteristics as Laribacter hongkongensis described in previous publications. This discovery proves that Laribacter hongkongensis is also associated with community-acquired gastroenteritis outside Hong Kong.