Phytochemical and antiinflammatory studies on Terminalia catappa

The antiinflammatory activity of Terminalia catappa leaves ethanolic extract was studied using 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema in acute and chronic models. A bioassay-oriented fractionation procedure showed that the activity concentrates in the chloroform fraction. Ursolic acid (1) and 2alpha,3beta,23-trihydroxyurs-12-en-28-oic acid (2), isolated from the chloroform fraction, exhibited strong antiinflammatory activities. The results suggest that the triterpenic acids 1 and 2 are responsible for the antiinflammatory activity of T. catappa leaves.     

分月扇舟蛾生物学特性及其综合防治

分月扇舟蛾在吉林敦化区一年一代，以三龄幼虫在落叶间吐丝作茧越冬。该虫有两个幼虫为害期，以五月下旬至六月上旬为害最为严重。初步查明，在敦化连续两年4、5月份干旱和特殊林分环境是发生分月扇舟蛾幼虫为害的主要原因。本文还提出了分月扇舟蛾的综合防治措施。     

High-level expression of 4-coumarate:coenzyme A ligase gene Pt4CL1 of Populus tomentosa in E. coli

In order to investigate the enzymatic properties of the 4CL1 of Populus tomentosa, the recombinant expression vector pQE31-4CL1 was constructed. The recombinant was identified by three restriction endonucleases, then the vector pQE31-4CL1 was transformed into expression host M15 (pREP4) and induced by isopropyl-α-D-thiogalactoside (IPTG) to express 60 kD fused protein Pt4CL1. The biologically active Pt4CL1, expressed as soluble protein, was achieved with 0.6 mmol·L-1 IPTG induction as the ex-pression temperature declined from 37 to 28°C. The 6×His tag facilitates affinity binding to Ni2 -nitrolotriacetic acid (NTA) and enables one-step purification to acquire the molecular SDS-PAGE electrophoresis purity of the active 4CL1 protein by agarose cou-pled with Ni2 -NTA affinity chromatography. The optimal substrate for Pt4CL1 was 4-coumarate.     

Effects of Cold Drawing and Water Quench Process on Mechanical Properties Prestressed Wires

Effects of cold drawing and water quench process on mechanical properties of prestressed wires have been studied in laboratory. It shows that sorbitized treat using water quench replacing lead quench is possible for Carbon steels prestressed wires. The cold drawing and water quench process which enable the mechanical properties of wires reaching specified demand of present standards are determined.     

NONPROPORTIONAL CYCLIC PLASTICITY FOR METALLIC MATERIALS

In order to describe nonproportional cyclic plasticity of polycrystalline metallic materials, the hardening function is separated into three factors, in which,f1 is related to the hardening parameter determined by plastic strain range, and f2 and f3 are related to the change of plastic deformation path characterized by a measure of nonproportionality. The main features of this work are: (a)cyclic hardening is described by f1, and additional hardening is separated into instantaneous and hereditary one which is described by f2 and f3 respectively; (b)a general form of the evolution of f1(i= 1,2, 3) is proposed; (c)parameters a1 and a3 are introduced to keep the memory to the largest cyclic hardening and additional hardening respectively; (d)various hardening mechanisms are embedded into a thermomechanically consistent constitutive equation. The capability of the developed model is verified with the analysis of biaxially nonproportional experiments by Benallal et al, Tanaka et al and Ohashi et al.     

Analysis on USB Driver Based on VxWorks Operation System

Recently, USB systems based on VxWorks are widely used in the embedded system. In this paper, the architecture of the VxWorks Operation System, the embedded USB system and the USB host stack are analyzed. This gives the technical method to development of the USB driver based on VxWorks.     

Local Nonlinear Forecasting of Short-term Power Load Forecasting

The nearest points in phase space are determined by Euclid distance in chaotic local prediction. The prediction accuracy depends on quality of the nearest points. But the shortest distance does not imply better forecasting effect. While false nearest neighboring point or high embedding dimensions appear evolvement track of some nearest neighboring point should be apart from prediction point. Because it is difficult for Euclid distance to reflect the correlation degree between the nearest points and prediction point. So the idea of combining Euclid distance with correlation degree is put forward. The method is applied to short-term electrical load forecasting. The result of load series forecasting by the presented method is more effective to improve prediction accuracy.     

Lipid characterization of mangrove thraustochytrid--Schizochytrium mangrovei

Lipid class composition and distribution of fatty acids within the lipid pool of microalga, Schizochytrium mangrovei FB3 harvested at the late exponential phase, was studied, with special emphasis on the distribution of docosahexaenoic acid (C22:6 n-3, DHA). Neutral lipids were the major lipid constituents (95.90% of total lipids) in which triacylglyerol (TAG) was the predominant component and accounted for 97.20% of the neutral lipids. Phosphatidylcholine (PC) was the major polar lipid. Phosphatic acid and phosphatidylserine were the two classes in phospholipids reported for the first time in thraustochytrids. Both TAG and PC were primarily saturated and consisted of C16:0 at approximately 50% of total fatty acids. DHA was found to be distributed in all lipid classes and to be the major polyunsaturated fatty acid. TAG contained the highest amount of DHA, although the percentage of DHA in total fatty acids in TAG (29.74%) was lower than that in PC (39.61%). The result from this study would be useful for further optimization of DHA production by S. mangrovei.