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Volume 12 No. 4
20 April 2007

2007, 12(4): 361-365.   doi:10.1016/S1007-0214(07)70054-8
Abstract ( 144 )  ( 50 )   Save
Chitosan/heparin microspheres were prepared using the water-in-oil emulsification solvent evaporation technique. The microsphere diameters were controlled by selecting the fabrication process parameters. Scanning electron micrographs showed that the chitosan/heparin microspheres were regular and the surface morphology was smooth. Fourier transform infrared showed that the chitosan amino groups reacted with heparin carboxylic groups to form acylamides in the microspheres. Analysis of the microsph...

2007, 12(4): 366-371.   doi:10.1016/S1007-0214(07)70055-X
Abstract ( 140 )  ( 36 )   Save
Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) scaffolds were prepared by thermally inducing phase separation (TIPS) for bone reconstruction. Scanning electron microscopy and porosity measurements were used to analyze the structure and properties of the scaffolds. The pore diameter of the scaffolds could be easily controlled by changing the quenching temperature and time. The biocompatibility was assessed by examining the proliferation and morphology of MC 3T3-E1 osteoprogenitor...

2007, 12(4): 372-380.   doi:10.1016/S1007-0214(07)70056-1
Abstract ( 176 )  ( 25 )   Save
The effects of genistein on several tumor cell lines were investigated to study the effects of genistein on cell growth, cell cycle, and apoptosis of two murine melanoma cell lines, B16 and K1735M2. These two closely related murine melanoma cell lines, however, have different responses to the genistein treatment. Genistein inhibits the growth of both the B16 and K1735M2 cell lines and arrests the growth at the G2/M phase. After treatment with 60 μmol/L genistein for 72 h, apoptosis and caspase a...

2007, 12(4): 381-388.   doi:10.1016/S1007-0214(07)70057-3
Abstract ( 82 )  ( 19 )   Save
In oyster biomineralization, large amounts of calcium are absorbed from external media, transported to the mineralization site, and finally deposited via a matrix-mediated process. All these activities are very energy intensive; therefore, investigations of the energy metabolism pathways of different oyster tissues will facilitate understanding of oyster biomineralization physiology. A full-length cDNA encoding the F1-ATPase beta-subunit (the F1-β-subunit, a major calalytic...

2007, 12(4): 389-393.   doi:10.1016/S1007-0214(07)70058-5
Abstract ( 138 )  ( 55 )   Save
A simple size-exclusion high-performance liquid chromatographic method was developed for rapid molecular mass screening to determine the average molecular mass, polydispersity, and quantity of Taizishen polysaccharides extract. The screening used a TOSOH TSK-GEL G3000SW high-performance liquid chromatographic column with 0.1 mol/L NaNO3 buffer as the mobile phase and refractive index detector. The molecular mass calibration curve was linear for polysaccharide standards from 10 to 100 ...

2007, 12(4): 394-399.   doi:10.1016/S1007-0214(07)70059-7
Abstract ( 132 )  ( 20 )   Save
The objective of this study is to quantify the puerarin in rat plasma following oral administration of TZ18 and compare the pharmacokinetics characteristics of puerarin in normal rats with that in depression model rats. A high performance liquid chromatography method was used to quantify the puerarin due to its good selectivity and linearity (coefficient correlation, r2= 0.9991) within the tested range (0.028-0.889 μgb · mL−1). Intra- and inter-day pre...

2007, 12(4): 400-404.   doi:10.1016/S1007-0214(07)70060-3
Abstract ( 204 )  ( 19 )   Save
Polyphenol oxidase (PPO) is the enzyme responsible for enzymatic browning during the growth of insects. It is also involved in defense reactions and is related with immunities in insects. PPO, a metalloenzyme oxidase, catalyzes the oxidation of o-diphenol to o-quinone. The present paper describes the effects of benzaldehyde and its p-substituted derivatives on the activity of PPO from the fifth instar of Pieris rapae L. PPO from the fifth instar of Pieris ...

2007, 12(4): 405-412.   doi:10.1016/S1007-0214(07)70061-5
Abstract ( 113 )  ( 19 )   Save
Mitochondrial ATP synthase is responsible for the production of the majority of the cellular ATP, which is composed of two major units: F0 and F1. Although much is known about the active complex (5 subunits (αβγδ?)), the role of the α subunit in the catalytic mechanism remains unclear, particularly in bivalve animals. This study first cloned and identified the full-length sequence of the mitochondrial H+-ATP synthase α subunit cDNA gene in Pinctada fucata

2007, 12(4): 413-423.   doi:10.1016/S1007-0214(07)70062-7
Abstract ( 102 )  ( 29 )   Save
The vegetation spatial heterogeneity and ecological characteristics in different soil regions were analyzed by surveying the vegetation in 12 different soil regions of Inner Mongolia, China, including coniferous-broadleaf deciduous forests, shrub, grassland, and desert regions with 1122 large 2 cm × 2 cm quadrats (actual size 30 km × 30 km, referred to as L-quadrat hereafter) in about 1.18 million km2. Each L-quadrat was divided into four small 1 cm × 1 cm quadrats (...

2007, 12(4): 424-434.   doi:10.1016/S1007-0214(07)70063-9
Abstract ( 158 )  ( 34 )   Save
The spatial heterogeneity and ecological characteristics of 74 vegetation types and the lack of vegetation type within the 9.6 million km2 of Chinese territory were studied using data from the China vegetation map. The analysis used 877 large quadrats 10 mm×10 mm (actual size 100 km×100 km), which covered about 8.77 million km2. Each large-quadrat was divided into four small 5 mm×5 mm quadrats (actual size 50 km×50 km). The frequency of occurrence of...

2007, 12(4): 435-440.   doi:10.1016/S1007-0214(07)70064-0
Abstract ( 117 )  ( 30 )   Save
As the world's largest developing country, China must face the problem of managing municipal solid waste, and the challenge of organic waste disposal is even more serious. Considering the characteristics of traditional waste disposal technologies and the subsequent secondary pollution, anaerobic digestion has various advantages such as reduction in the land needed for disposal and preservation of environmental quality. In light of the energy crisis, this paper focuses on the potential production...

2007, 12(4): 441-446.   doi:10.1016/S1007-0214(07)70065-2
Abstract ( 189 )  ( 32 )   Save
With hard turning, which is an attractive alternative to existing grinding processes, surface quality is of great importance. Signal processing techniques were used to relate workpiece surface topography to the dynamic behavior of the machine tool. Spatial domain frequency analyses based on fast Fourier transform were used to analyze the tool behavior. Wavelet reconstruction was used for profile filtering. The results show that machine vibration remarkably affects the surface topography at small...

2007, 12(4): 447-452.   doi:10.1016/S1007-0214(07)70066-4
Abstract ( 171 )  ( 38 )   Save
Automatic production and precise positioning of carbon fiber reinforced plastics (FRP) require precise detection of the fiber orientations. This paper presents an automatic method for detecting fiber orientations of sewed carbon fibers in the production of FRP. Detection was achieved by appropriate use of regional filling, edge detection operators, autocorrelation methods, and the Hough transformation. Regional filling was used to reduce the influence of the sewed regions, autocorrelation was us...

2007, 12(4): 453-458.   doi:10.1016/S1007-0214(07)70067-6
Abstract ( 105 )  ( 23 )   Save
Future steam turbines will use hollow structures so that the turbine inlet temperature can be increased to improve the thermal efficiency. These hollow structures are made of the nickel-base alloy Nicrofer 6025 HT and consist of a wire mesh between two cover sheets. The cover sheets can be joined to the wire mesh by capacitor discharge welding due to its extremely short welding duration. The goal of this research is to investigate suitable welding parameters so that the weld spots form in an opt...

2007, 12(4): 459-465.   doi:10.1016/S1007-0214(07)70068-8
Abstract ( 117 )  ( 68 )   Save
Let G = (V, E) be a complete undirected graph with vertex set V, edge set E, and edge weights l(e) satisfying the triangle inequality. The vertex set V is partitioned into clusters V1, V2, …, Vk. The clustered traveling salesman problem (CTSP) seeks to compute the shortest Hamiltonian tour that visits all the vertices, in which the vertices of each cluster ar...

2007, 12(4): 466-474.   doi:10.1016/S1007-0214(07)70069-X
Abstract ( 147 )  ( 32 )   Save
The influence of different information sharing scenarios in a single supplier-single retailer supply chain is analyzed. The five information sharing scenarios are centralized information sharing, full information sharing, supplier-dominated information sharing, retailer-dominated information sharing, and non-information sharing. Iterative procedures are developed to obtain the inventory policies and the system costs at equilibrium points. Numerical examples show that the cost of a centralized in...

2007, 12(4): 475-478.   doi:10.1016/S1007-0214(07)70070-6
Abstract ( 105 )  ( 29 )   Save
Imaginary cyclic fields of degree p-1 which have two distinct unramified cyclic extensions of degree p are produced using elementary properties of the Lucas sequences. An infinite family of imaginary cyclic fields of degree p-1 are then given with the p-rank of the ideal class groups of at least two.

2007, 12(4): 479-484.   doi:10.1016/S1007-0214(07)70071-8
Abstract ( 108 )  ( 64 )   Save
In this paper, we mainly study the relation of two cyclically reduced words w and w' on the condition they have the same trace polynomial (i.e., tr w=tr w'). By defining an equivalence relation through such operators on words as inverse, cyclically left shift, and mirror, it is straightforward to get that

2007, 12(4): 485-492.   doi:10.1016/S1007-0214(07)70072-X
Abstract ( 104 )  ( 22 )   Save
The kinetics of the sorption of Cd2+ and Cr3+ from aqueous solutions by mercaptoacetic acid modified and unmodified oil palm fruit fibre adsorbents were investigated. The results indicate that sorption equilibrium was reached within 60 min for both metals. Also, the removal efficiency of the three adsorbents was observed to increase for both metals with stronger treatments with mercaptoacetic acid. This may be attributed to the influence of the thiolation of the adsorbents....

2007, 12(4): 493-496.   doi:10.1016/S1007-0214(07)70073-1
Abstract ( 125 )  ( 38 )   Save
Amphiphilic diblock copolymers composed of methoxy polyethylene glycol (MePEG) and poly(D,L-lactide) (PDLLA) were prepared for the preparation of polymeric micelles. The use of MePEG-PDLLA as drug carriers has been reported in the open literature, but there are only few data on the application of a series of MePEG-PDLLA copolymers with different lengths in the medical field. The shape of the polymeric micelles is also important in drug delivery. Studies on in vitro dru...