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The complex [Dy4(L1)2(CH3COO)4(DMF)3] (1) was obtained by using 2,6-bis(2-((E)-(8-hydroxyquinolin-2-yl)methylene)hydrazine-1-carbonyl)pyridine 1-oxide (H4L1) and Dy(CH3COO)3·4H2O under 100 in N,N-dimethylformamide (DMF) solvent. Structure analyzing showed that Dy(III) ions had two types of configuration with D2d and C4v. AC magnetic susceptibilities exhibited that complex 1 was an obvious single-molecule magnet (SMM) with obvious ac susceptibilities at zero Oe static magnetic field over the frequency range of 9–999 Hz. These findings demonstrated potential applications of polydentate ligands for the synthesis of SMMs. [ABSTRACT FROM AUTHOR]

We successfully obtained two type of heterometallic complexes [Fe4Dy2(L1)2(µ4-O)2(piv)4(H2O)2(NO3)4]·CH3CN·CH3OH (1) and [Fe6Dy2(L1)2(µ4-O)2(CH3COO)6(OH)2(H2O)2(NO3)6]·CH3CN (2) by using 2,2′-((2-((2-hydroxyethyl)amino)cyclohexyl)azanediyl)bis(ethan-1-ol) (H3L1), Dy(NO3)3·6H2O, FeCl3 and pivalic acid (piv) or acetic acid under room temperature in different solvent. Crystal structure showed that the central structure of [ Fe 4 III (µ4-O)2]8+ arranged in what was often termed an absent cubic shape, although here the Fe centers were strictly coplanar. Each Fe3 triangle was connected to the capping Dy(III) through µ4-O bridges for complex 1, and each Fe3 triangle was connected to the capping Fe(III) through µ4-O bridges for complex 2. It might be due to the steric effect that the coordination atoms of piv ligands chelated and blocked the structure. AC magnetic susceptibilities exhibited that complex 1 and 2 showed out-of-phase (χ″) component of ac-susceptibilities at zero Oe static magnetic field over the frequency range of 9–999 Hz, which energy barriers were 0.44 and 0.13 K. And their energy barriers were 1.2 and 12.2 K at applied 1000 Oe static magnetic field. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the feasibility of a double-acquisition coronary CT angiography (CCTA) protocol in the presence and absence of an intravenous (IV) vasodilator infusion for detecting vasospastic angina.Methods: Twenty patients with a high clinical probability of vasospastic angina were enrolled. All subjects underwent baseline CCTA without a vasodilator in the early morning followed by a catheterized coronary angiography with ergonovine provocation test. Within 3 days, all subjects underwent repeat CCTA during a continuous IV infusion of nitrate. Vasospastic angina as detected by CCTA was defined as significant stenosis (≥50 %) with negative remodelling without definite plaques or diffuse small diameter (<2 mm) of a major coronary artery with a beaded appearance on baseline CT that completely dilated on IV nitrate CT. The CCTA results were compared to the catheterized ergonovine provocation test as the reference standard.Results: Among 20 patients, the catheterized ergonovine provocation test detected vasospasm in 15 patients. The sensitivity, specificity, positive predictive value and negative predictive value of CCTA in a per-patient-based analysis were 73, 100, 100 and 56 %, respectively.Conclusions: Double-acquisition CCTA in the presence and absence of IV infusion of nitrate allows noninvasive detection of vasospastic angina with moderate sensitivity and high specificity.Key Points: • Limited data exist regarding the efficacy of CCTA in detecting vasospastic angina. • We propose a double-acquisition CCTA protocol with and without IV nitrate injections. • This protocol provides 100% specificity and moderate sensitivity (73%) in spasm detection. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine if plasma membrane vesicles (PMVs) could be exploited for efficient transfer of macro-biomolecules and mitochondria. PMVs were derived from mechanical extrusion, and made fusogenic (fPMVs) by incorporating the glycoprotein G of vesicular stomatitis virus (VSV-G). Confocal microscopy examination revealed that cytoplasmic proteins and mitochondria were enclosed in PMVs as evidenced by tracing with cytoplasmically localized and mitochondria-targeted EGFP, respectively. However, no fluorescence signal was detected in PMVs from cells whose nucleus was labeled with an EGFP-tagged histone H2B. Consistently, qRT-PCR measurement showed that mRNA, miRNA and mitochondrial DNA decreased slightly; while nuclear DNA was not measureable. Further, Western blot analysis revealed that cytoplasmic and membrane-bound proteins fell inconspicuously while nuclear proteins were barely detecsle. In addition, fPMVs carrying cytoplamic DsRed proteins transduced about ~40 % of recipient cells. The transfer of protein was further confirmed by using the inducible Cre/loxP system. Mitochondria transfer was found in about 20 % recipient cells after incubation with fPMVs for 5 h. To verify the functionalities of transferred mitochondria, mitochodria-deficient HeLa cells (Rho0) were generated and cultivated with fPMVs. Cell enumeration demonstrated that adding fPMVs into culture media stimulated Rho0 cell growth by 100 % as compared to the control. Lastly, MitoTracker and JC-1 staining showed that transferred mitochondria maintained normal shape and membrane potential in Rho0 cells. This study established a time-saving and efficient approach to delivering proteins and mitochondria by using fPMVs, which would be helpful for finding a cure to mitochondria-associated diseases. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Purpose: The aim of this review was to compare the clinical outcomes between operative and conservative management for primary patella dislocation (PPD). Methods: PubMed Medline, EMBASE, Google scholar, and the Cochrane Library were systematically searched for randomized controlled trials that compared operative technique versus conservative technique for PPD. The results of eligible studies were independently extracted and analyzed according to the following: patient's satisfaction, Kujala score, Tegner score, and redislocation rate. Random-effect and fixed-effect models were adopted to calculate the weight mean difference and the odds ratio for continuous and dichotomous variables with 95 % confidence interval. Results: Seven studies met the inclusion criteria, resulting in 402 (216 surgery and 186 conservation) patients available for the present study. A meta-analysis showed no significant differences between the two treatment groups in terms of patient's satisfaction and Kujala score. However, significant differences in Tegner score ( P < 0.00001) and redislocation rate ( P = 0.002) were observed in favor of surgical treatment. In the subgroup analysis, surgical intervention achieved higher ( P = 0.002) Kujala score in short term (<5 years), while conservation gained advantage ( P = 0.003) in long term (>5 years). There was no significant difference in dislocation rate in long term. Conclusions: Surgical treatment might provide better clinical results in short term. More persuasive evidence is still needed to proof the effect of surgical management in long time. [ABSTRACT FROM AUTHOR]

The chemoenzymatic process involving biocatalytic resolution of rac-2-carboxyethyl-3-cyano-5-methylhexanoic acid ethyl ester (CNDE, 1) has been the most competitive and attractive route for pregabalin. A new esterase-producing strain ZJB-09203, which exhibited high hydrolytic activity, excellent enantioselectivity, and diastereoselectivity towards CNDE, has been successfully isolated from soil samples with a pH indicator agar plate method. The isolate was identified as Morgarella morganii by the ATB system (ID 32 GN) and the 16S rDNA sequence. In order to suppress product inhibition during enzymatic hydrolysis of CNDE, an adsorptive biocatalytic process was developed by utilizing anion-exchange resin D201 as adsorbent for selective removal of (3 S)-2-carboxyethyl-3-cyano-5-methylhexanoic acid ( 2) from the reaction medium. This approach allowed the substrate loading to be increased up to 1.5 M and the chiral intermediate 2 was produced in 682 mM, 45.3 % conversion, and 95 % ee. These results imply that M. morganii ZJB-09203 esterase is a promising biocatalyst in the development of chemenzymatic manufacturing process for pregabalin. [ABSTRACT FROM AUTHOR]

Redox effector factor (Ref-1) is a sensitive marker for oxidative cellular injury. The aim of this study was to investigate the effects of acupuncture on hippocampal Ref-1 expression in cerebral multi-infarction rats. The rats with reference memory impairment were randomly allocated to three groups: impaired group, acupuncture group and placebo acupuncture group. Moreover, normal group and sham-operated group were set as control groups. Morris water maze test showed that cerebral multi-infarction rats did not present significant changes in spatial working memory performance. Further investigation by immunohistochemistry revealed that acupunctural treatment significantly increased the expression of Ref-1 in the hippocampus of the impaired rats. These findings suggested that the spatial working memory was unaffected in the cerebral multi-infarction rats although spatial reference memory deficits were detected in our previous study; in addition, acupuncture could increase the Ref-1 expression, consequently exerting the anti-oxidant effects. [ABSTRACT FROM AUTHOR]

We wished to elucidate a potential role of the tumor necrosis factor-like weak inducer of apoptosis (TWEAK)/fibroblast growth factor-inducible molecule 14 (Fn14) axis in myocardial fibrosis. Stimulation of neonatal rat cardiac fibroblasts (CFs) with TWEAK could increase CFs numbers and collagen synthesis. Conversely, when CFs were pretreated with siRNA against Fn14, induction of cell proliferation and collagen synthesis by TWEAK were inhibited. Pretreatment with TWEAK on CFs induced activation of the nuclear factor-kappaB (NF-кB) pathway and subsequently increased the production of metalloproteinase-9 (MMP-9). Cell treatment with siRNA against Fn14 led to inhibition of the NF-кB pathway. Additionally, after stimulation of cell with ammonium pyrrolidine dithiocarbamate, cell proliferation and collagen synthesis induced by NF-кB and the upregulation of MMP-9 production were inhibited. The present study suggested that the TWEAK/Fn14 axis increased cell proliferation and collagen synthesis by activating the NF-кB pathway and increasing MMP-9 activity. This axis may be important for regulating myocardial fibrosis. [ABSTRACT FROM AUTHOR]

Based on the discussion of the concept of the developmental state and the socialist developmental state, this article describes and analyzes the development process of China's economy and society since the reform and opening from the perspective of state transformation, and explores the deep-level causes of the difficulties contemporary China is facing in its economic and social development. It argues that the Chinese state has gradually become a developmental state with a new form, which has played an important role in promoting the development of China's economy and society but meanwhile has brought some negative impacts. China has made many efforts to go beyond the developmental state, and achieved notable success in various aspects since 2002, but there are still many problems, especially when struck by the 2008 world financial crisis; the negative impacts of the developmental state are gradually emerging. Moreover, the Chinese government still tends to sidestep some systemic and structural problems, and some policies are in fact consolidating the dominance of the old system, which will inevitably increase the difficulties for the Chinese state to go beyond the developmental state. [ABSTRACT FROM AUTHOR]

Grinding is an energy-intensive process in which the heat generated can cause various types of thermal damage to workpiece. Many theoretical, empirical or numerical models have been developed to predict grinding temperature. However, these models are not directly applicable for coated workpieces. Tools or other parts are coated with hard materials like tungsten carbide, ceramics or polycrystalline diamond to increase their surface hardness and prolong their life expectancy. In this paper, an empirical model is proposed to predict the maximum grinding temperature of coated workpieces. Experimental and numerical studies are carried out to validate the model. The results indicated that the new model is able to accurately predict grinding temperature. [ABSTRACT FROM AUTHOR]

Several rhizobacteria play a vital role in plant protection, plant growth promotion and the improvement of soil health. In this study, we have isolated a strain of Lysobacter antibioticus HS124 from rhizosphere and demonstrate its antifungal activity against various pathogens including Phytophthora capsici, a destructive pathogen of pepper plants. L. antibioticus HS124 produced lytic enzymes such as chitinase, β-1,3-glucanase, lipase, protease, and an antibiotic compound. This antibiotic compound was purified by diaion HP-20, silica gel, sephadex LH-20 column chromatography and high performance liquid chromatography. The purified compound was identified as 4-hydroxyphenylacetic acid by gas chromatography-electron ionization (GC-EI) and gas chromatography-chemical ionization (GC-CI) mass spectrometry. This antibiotic exhibited destructive activity toward P. capsici hyphae . In vivo experiments utilizing green house grown pepper plants demonstrated the protective effect of L. antibioticus HS124 against P. capsici. The growth of pepper plants treated with L. antibioticus culture was enhanced, resulting in greater protection from fungal disease. Optimum growth and protection was found when cultures were grown in presence of Fe(III). Additionally, the activities of pathogenesis-related proteins such as chitinase and β-1,3-glucanase decreased in roots, but increased in leaves with time after treatment compared to controls. Our results demonstrate L. antibioticus HS124 as a promising candidate for biocontrol of P. capsici in pepper plants. [ABSTRACT FROM AUTHOR]

Alkyl glucosides were synthesized by the reaction of Leuconostoc mesenteroides dextransucrase with sucrose and various alcohols. Alkyl α- d-glucosides were obtained with a yield of 30% (mol/mol) with primary alcohols, but secondary alcohols or tertiary alcohols gave yields below 5%. The optimal yield was 50% using 1-butyl α- d-glucoside with 0.9 M 1-butanol. The acceptor products of methanol or ethanol were confirmed as methyl α- d-glucopyranoside and ethyl α- d-glucopyranoside via MALDI-TOF MS and NMR analysis. Thus, methyl or ethyl α- d-glucoside constituted half the emulsification activities of Triton X-100 as commercially available surfactants. [ABSTRACT FROM AUTHOR]

The technology of superabrasive grinding has been developed in order to achieve high-quality finish in extremely hard and brittle materials. Thereafter, truing and dressing technology on super abrasive grinding wheel is one of the most important subjects on precise machining field at present. In this paper, mist-jetting electrical discharge technology was applied to dressing metal-bonded superabrasive wheels. And a systematical study on the mechanism of selective removal of the bond was proposed. Experiments on dressing bronze bonded diamond grind wheels were carried out on a die-sinking electrical discharge machine. The diamond wheel topographies before and after electrical discharge dressing were observed by VH-800 3D digital microscope. The wheel profiles before and after dressing were observed. The results of electrical discharge dressing under different electrical parameters were compared. Experimental results indicate that the favorable surface topography can be obtained under suitable processing parameters and mist-jetting electrical discharge dressing (MEDD) is feasible for metal-bonded diamond grinding wheel. [ABSTRACT FROM AUTHOR]

Abstract   Objective To explore the correlation of matrix metalloproteinase-1 (MMP1) and tissue inhibitor of metalloproteinase-1 (TIMP1) with pituitary adenoma fibrosis. Methods Thirty-eight pituitary adenoma specimens were divided into fibrous group (6 patients) and non-fibrous group (32 patients). MMP1 and TIMP1 expression was detected by RT-PCR and immunohistochemistry. The collagen content was determined by Sirius scarlet staining. Results In fibrous and non-fibrous group: (1) the collagen content was 20.95 ± 8.42% and 7.98 ± 5.18% respectively, and there was a statistical significance (P 1mRNA was 0.47 ± 0.40 and 0.59 ± 0.54 respectively and its protein expression was 0.12 ± 0.09 and 0.13 ± 0.09 respectively, and there was no statistical significance (P > 0.05). Their expression was not related to collagen content (P > 0.05). (3) The expression of TIMP1mRNA was 1.61 ± 1.09 and 0.79 ± 0.59 respectively and its protein expression was 0.58 ± 0.11 and 0.32 ± 0.18 respectively, and there was a statistical significance (P P Conclusion The pathological features of pituitary adenoma fibrosis are excessive collagen deposition. High expression of TIMP1 may be an important cause. [ABSTRACT FROM AUTHOR]

In this paper, an online measurement and error compensation system for curve grinding based on pattern recognition was presented and verified by experiments. The measurement system organization and its principle of operation were introduced in detail. The work piece and grinding wheel image were sampled at certain positions to avoid spark influence. In order to increase system resolution, images were sampled only at local areas of the work piece and grinding wheel. A discrimination technology based on a circular tolerance zone was proposed which can solve the problem of local image edge comparison. For image de-noising, a local threshold algorithm was applied to determine new wavelet coefficients. Furthermore, a two-step edge detection method was used to realize sub-pixel precision. Finally, a series of experiments were carried out to examine the detection precision of the image measurement system and its influencing factors. From experiments, it can be said that the proposed method in this paper is effective, and its detection precision is much better than traditional methods. [ABSTRACT FROM AUTHOR]

For the improvement of machining precision and stability of the grinding process it is very important to perform research on wear detection of the wheel. Conventional wear detection methods depended on the wheel’s optical projection, and its detection error was relatively large due to more subjective factors in the detection process. Meanwhile, non-contact acquisition and processing of the object could be realized by the use of digital image processing technology, and the processing precision and stability was relatively good. Thus, the technology of digital image acquisition and recognition was applied in the research of wear detection of the wheel in precision NC curve grinding. In this work, the working process of new-type curve point grinding based on normal tracing is first introduced in detail; second, the evaluation method of the wheel’s wear is presented, and a description of the wear detection system of the wheel which was built. Lastly a location algorithm of sub-pixels was studied in order to improve the detection precision of the wheel’s wear. Experimental results of wear detection of the wheel showed great improvement of machining precision and verified the effectiveness of wear detection of the wheel based on digital image acquisition and recognition. [ABSTRACT FROM AUTHOR]

The bending problem of a functionally graded anisotropic cantilever beam subjected to thermal and uniformly distributed load is investigated, with material parameters being arbitrary functions of the thickness coordinate. The heat conduction problem is treated as a 1D problem through the thickness. Based on the elementary formulations for plane stress problem, the stress function is assumed to be in the form of polynomial of the longitudinal coordinate variable, from which the stresses can be derived. The stress function is then determined completely with the compatibility equation and boundary conditions. A practical example is presented to show the application of the method. [ABSTRACT FROM AUTHOR]

The bending problem of a functionally graded anisotropic cantilever beam subjected to a linearly distributed load is investigated. The analysis is based on the exact elasticity equations for the plane stress problem. The stress function is introduced and assumed in the form of a polynomial of the longitudinal coordinate. The expressions for stress components are then educed from the stress function by simple differentiation. The stress function is determined from the compatibility equation as well as the boundary conditions by a skilful deduction. The analytical solution is compared with FEM calculation, indicating a good agreement. [ABSTRACT FROM AUTHOR]

A revolving electromagnetic actuation mechanism composed of an electromagnetic stator and an electromagnetic rotor has been developed for boring non-circular holes. The main component of the rotor is a flexure-hinged based flexible body. There are four pole-pair coils in the stator supplying actuation currents. The micro-displacement between the stator and rotor can be controlled by changing the currents applied in the pole-pair coils. Through linearization of the actuation force near the static action point, a linear relationship between the control current and the actuation force was established, and the synchronizing control method of the electromagnetic actuation mechanism is presented here. With two-factor analysis of the linearization error of the actuation force, the influences of control current and micro-displacement to the linearization error of the actuation force were studied. Then, the principle for designing the basic parameters of the magnetic actuation mechanism is put forward. The calibration of the mechanism indicates that the relationship between the micro-displacement of the rotor and the control current has linear characteristics in the required micro-displacement range. Simulation tests show that the turning radius of the rotor changes with the control current. The proposed mechanism can feasibly supply a controllable micro displacement to the boring bar. [ABSTRACT FROM AUTHOR]

The analytical solutions of the stresses and displacements were obtained for fixed-fixed anisotropic beams subjected to uniform load. A stress function involving unknown coefficients was constructed, and the general expressions of stress and displacement were obtained by means of Airy stress function method. Two types of the description for the fixed end boundary condition were considered. The introduced unknown coefficients in stress function were determined by using the boundary conditions. The analytical solutions for stresses and displacements were finally obtained. Numerical tests show that the analytical solutions agree with the FEM results. The analytical solution supplies a classical example for the elasticity theory. [ABSTRACT FROM AUTHOR]

Compost sustaining a multitude of chitinase-producing bacteria was evaluated in a greenhouse study as a soil amendment for the control of late blight (Phytophthora capsici L.) in pepper (Capsicum annuum L.). Microbial population and exogenous enzyme activity were measured in the rhizosphere and correlated to the growth and health of pepper plant. Rice straw was composted with and without a chitin source, after having been inoculated with an aliquot of coastal area soil containing a known titer of chitinase-producing bacteria. P. capsici inoculated plants cultivated in chitin compost-amended soil exhibited significantly higher root and shoot weights and lower root mortality than plants grown in pathogen-inoculated control compost. Chitinase and β-1,3-glucanase activities in rhizosphere of plants grown in chitin compost-amended soil were twice that seen in soil amended with control compost. Colony forming units of chitinase-producing bacteria isolated from rhizosphere of plants grown in chitin compost-amended soil were 103 times as prevalent as bacteria in control compost. These results indicate that increasing the population of chitinase-producing bacteria and soil enzyme activities in rhizosphere by compost amendment could alleviate pathogenic effects of P. capsici. [ABSTRACT FROM AUTHOR]