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A realistic kinetic Monte Carlo (KMC) simulation model with physical parameters is developed, which well reproduces the heteroepitaxial growth of multilayered Ni thin film on Cu(100) surfaces at room temperature. The effects of mass transport between interlayers and edge diffusion of atoms along the islands are included in the simulation model, and the surface roughness and the layer distribution versus total coverage are calculated. Specially, the simulation model reveals the transition of growth mode with coverage and the difference between the Ni heteroepitaxy on Cu(100) and the Ni homoepitaxy on Ni(100). Through comparison of KMC simulation with the real scanning tunneling microscopy (STM) experiments, the Ehrlich–Schwoebel (ES) barrier Ees is estimated to be 0.18±0.02 eV for Ni/Cu(100) system while 0.28 eV for Ni/Ni(100). The simulation also shows that the growth mode depends strongly on the thickness of thin film and the surface temperature, and the critical thickness of growth mode transition is dependent on the growth condition such as surface temperature and deposition flux as well.

A tumour vascular network, characterized as an irregularly stochastic growth, is different from the normal vascular network. We systematically analyse the dependence of the branching. It is found that anastomosis of tumour on time is according to a number of tumour images, and both the fractal dimensions and multifractal spectra of the tumours are obtained. In the cases studied, the fractal dimensions of the tumour vascular network increase with time and the multifractal spectrum not only rises entirely but also shifts right. In addition, the best drug delivery stage is discussed according to the difference of the singularity exponent δα(δα = αmax — αmin), which shows some change in the growth process of the tumour vascular network. A common underlying principle is obtained from our analysis along with previous results.

The behaviour of water and small solutes in confined geometries is important to a variety of chemical and nanofluidic applications. Here we investigate the permeation and distribution of water and ions in electrically charged carbon cylindrical nanopore during the osmotic process using molecular dynamics simulations. In the simulations, charges are distributed uniformly on the pores with diameter of 0.9 nm. For nanopores with no charge or a low charge, ions are difficult to enter. With the increasing of charge densities on the pores, ions will appear inside the nanopores because of the large electronic forces between the ions and the charged pores. Different ion entries induce varying effects on osmotic water flow. Our simulations reveal that the osmotic water can flow through the negatively charged pore occupied by K+ ions, while water flux through the positively charged pores will be disrupted by Cl- ions inside the pores. This may be explained by the different radial distributions of K+ ions and Cl- ions inside the charged nanopores.

We study the response of water permeation properties through a carbon nanotube on the time-dependent mechanical signals. It is found that there is a critical frequency of vibrating f(c) (about 1333 GHz) which plays a significant role in the water permeation properties. The total water flow, the net flux, the number of hydrogen bonds and the dipole flipping frequency of the single-file water chain inside the nanotube are almost unchanged for the frequency of vibrating f < f(c). Simulation results show that the nanotube can be effectively resistant to the mechanical noise. Such excellent effect of noise screening is attributed to the exceptional property of water molecules connected by strong hydrogen bonds with each other and forming a one-dimensional water chain inside the nanotube. Our findings are important for the understanding of why biological systems can achieve accurate information transfer in an environment full of fluctuations.

The process of the multilayer growth of Pt on Pt (111) is studied by using a Monte Carlo model with realistic physical parameters. The effects of the substrate temperature, the ES barrier, and the deposition rate on the growth mode have been investigated. Gradual transitions of the surface roughness from oscillatory to non-oscillatory behavior and then back to oscillatory behavior are observed while increasing the substrate temperature from 270 K to 620 K. It is found that the growth mode depends strongly on ES barrier over the whole temperatures and the deposition rate of atoms effectively affects the growth mode. The simulation results are consistent with many experimental observations for homoexpitaxy on a Pt (111) substrate.

To evaluate the public health risk of exposure to microcystins in fish food in China, the distribution pattern of microcystin-LR and microcystin-RR in various organs (liver, intestine, kidney, muscle and lipid) of the dominant freshwater phytoplanktivorous fish Hypophthalmichthys molitrix in Hangzhou, China's Tiesha River was investigated with the method of HPLC-ESI-MS analysis. The distribution of microcystins was different in the fish organs and the major total microcystins (microcystin-LR and microcystin-RR) were present in the intestines (6.49 micro g/g fresh weight), followed by the livers (4.52 micro g/g fresh weight) and the muscles (2.86 micro g/g fresh weight). Microcystins were detected in kidneys (1.35 micro g/g fresh weight), but not detected in lipid. The results suggested that the mean daily intake from fish was 0.03 micro g/kg body weight which was very close to the recommended WHO tolerable daily intake (TDI) level of 0.04 micro g/kg body weight per day, and local people were warned they may have health risk if they consumed fish from the river.

In this paper we present some simulation results about the behaviour of water molecules inside a single wall carbon nanotube (SWNT). We find that the confinement of water in an SWNT can induce a wave-like pattern distribution along the channel axis, similar phenomena are also observed in biological water channels. Carbon nanotubes(CNTs) can serve as simple nonpolar water channels. Molecular transport through narrow CNTs is highly collective because of tight hydrogen bonds in the protective environment of the pore. The hydrogen bond net is important for proton and other signal transports. The average dipoles of water molecules inside CNTs (7,7), (8,8) and (9,9) are discussed in detail. Simulation results indicate that the states of dipole are affected by the diameter of SWNT. The number of hydrogen bonds, the water–water interaction and water–CNT interaction are also studied in this paper.

To detect platelet anti-HPA-1a and -1b antibodies using recombinant GPIIIa fragments coupled to Luminex beads.The sensitivity of 2 techniques, monoclonal antibody specific immobilization of platelet antigen (MAIPA) and Luminex bead assay, was compared using 12 twofold-serial dilutions (from neat to 1 in 2048) of an anti-HPA-1a WHO international standard. The specificity of Luminex assay to identify anti-HPA-1a and -1b antibodies was assessed using 8 negative or positive controls and 36 blinded samples provided by WHO Platelet Workshop.The sensitivity of MAIPA and Luminex bead assay to detect anti-HPA-1a was dilution 1/64 (i.e. 1.56 IU/ml) and far more than dilution 1/2048 (i.e. 0.049 IU/mL), respectively. The Luminex bead assay could specifically identify negative and positive controls of anti-HPA-1a and -1b. All results of 36 blinded samples by Luminex assay were accordant to reference results except one sample which contained high concentration antithetical antibody and resulted in false positive of anti-HPA-1b. Cross-reactivity was also not observed with the samples containing HLA, ABO or other platelet antibodies.The Luminex beads coupled with recombinant GPIIIa fragments can be used to detect HPA-1 system antibodies with sufficient sensitivity and specificity, that is suitable for the detection of platelet alloantibodies in clinical alloimmune thrombocytopenia.

Mesenchymal stem cell (MSC) differentiation is regulated by the extracellular matrix (ECM) through activation of intracellular signaling mediators. The stiffness of the ECM was shown to be an important regulatory factor for MSC differentiation, and transcriptional coactivator with PDZ-binding motif (TAZ) was identified as an effector protein for MSC differentiation. However, the detailed underlying mechanism regarding the role of ECM stiffness and TAZ in MSC differentiation is not yet fully understood. In this report, we showed that ECM stiffness regulates MSC fate through ERK or JNK activation. Specifically, a stiff hydrogel matrix stimulates osteogenic differentiation concomitant with increased nuclear localization of TAZ, but inhibits adipogenic differentiation. ERK and JNK activity was significantly increased in cells cultured on a stiff hydrogel. TAZ activation was induced by ERK or JNK activation on a stiff hydrogel because exposure to an ERK or JNK inhibitor significantly decreased the nuclear localization of TAZ, indicating that ECM stiffness-induced ERK or JNK activation is important for TAZ-driven osteogenic differentiation. Taken together, these results suggest that ECM stiffness regulates MSC differentiation through ERK or JNK activation.

요 약 본 연구는 블루오션 전제조건의 하나인 고객가치혁신과 더불어 블루오션의 또다른 조건을 확인하고자 함을 목적으로 하고 있므며, 또한 시장을 세분화하고 적절한 전략을 수립함으로서 기업으로 하여금 블루 오션 시장에 진입할 수 있도록 하고자 함이다. 이러한 목적을 위해 본 연구메서는 차별화된 가치혁신 요 소를 지닌 시장에의 접근, 가치혁신에 의한 시장세분화, 블루오션 착시시장의 특성을 가진 주요변수, 블 루오션 시장진입을 위한 후발기업의 전략등의 문제를 다루고 있으며, 또한 가치와 관련된 문헌고찰, 블 루오션 전략, 실제사례에서의 객관적 자료의 활용 등을 통해 분석을 수행하였다 본 연구에서는 내구재 와 비내구재의 대표적 사례로 껍과 냉장고 시장을 선정하였고, 가치혁신을 기준으로 시장을 분류한 결과 블루오션 시장과 블루오션 착시시장의 존재를 확인할 수 있었다

By means of the Monte Carlo simulation, a fractal growth model is introduced to describe diffusion-limited aggregation (DLA) under rotation. Patterns which are different from the classical DLA model are observed and the fractal dimension of such clusters is calculated. It is found that the pattern of the clusters and their fractal dimension depend strongly on the rotation velocity of the diffusing particle. Our results indicate the transition from fractal to non-fractal behavior of growing cluster with increasing rotation velocity, i.e. for small enough angular velocity ω the fractal dimension decreases with increasing ω, but then, with increasing rotation velocity, the fractal dimension increases and the cluster becomes compact and tends to non-fractal.

Chessboard-like substrates are introduced in this paper, in order to study the diffusion-limited aggregation (DLA) and the motion of poly-atoms on heterogeneous surfaces. The effect of morphology of such substrates upon the cluster aggregation is investigated using the Monte Carlo simulation. It is found that the growth process and the cluster morphology are governed by the energetic topography of the substrates. Our simulation also indicate that the island density and the fractal dimension of the clusters depend strongly on the substrate topography and the activation energy.

Tissue destruction, resulting in emphysema, can be a consequence of several pathologic processes. The current study evaluated the effects of the phosphodiesterase (PDE)4 inhibitor, cilomilast, and other PDE inhibitors on the ability of fibroblasts to degrade extracellular matrix. Using the three-dimensional collagen gel culture system, fibroblasts (HFL-1) were cultured with tumor necrosis factor (TNF)-alpha, known to induce matrix metalloproteinase (MMP) release, and/or neutrophil elastase (NE), which can induce MMP activation. On Day 4, gels containing TNF-alpha and NE were significantly degraded (20.8 +/- 2.9% of original collagen content). Cilomilast (10 micro M) inhibited this degradation (84.4 +/- 8.4%). Amrinone, a PDE3 inhibitor, and zaprinast, a PDE5 inhibitor, had no effect. Gelatin zymography and immunoblotting revealed that fibroblasts cultured with TNF-alpha released increased amounts of latent MMP-1 and -9. The addition of NE resulted in the conversion of MMP-1 and -9 to their active forms, indicative of collagen degradation. Cilomilast inhibited the release of MMP-1 and -9, as well as conversion of MMP-1 to its active form. Using real-time PCR analysis, cilomilast's effect on MMP-1 release was not associated with the proteinase's mRNA expression, suggesting that the inhibition of release is regulated at the post-transcriptional level. These results suggest that cilomilast may be a potentially effective therapeutic agent in diseases characterized by excessive tissue destruction, such as emphysema.

Polychlorinated biphenyls are typical persistent chlorinated organic compounds in the environment. Bioremediation of PCB-contaminated environment has become one of the hot issues. In this study, vitamin B12 (VB12) and chlorine-free culture medium were applied to study the effects of VB12 on the degradation of 2,4,4'-trichlorobiphenyl (PCB28) by Nostoc PD-2 and the gene expression during the PCB-degradation process. Results showed that addition of different concentrations of vitamin B12 could improve the PCB-biodegradation rates by Nostoc PD-2. Compared with the control group, the 7-day degradation rate in 10 microg x L(-1), 100 microg x L(-1), and 1 000 microg x L(-1) VB12-treated groups increased by 11.0%, 19.7%, and 21.9% , respectively. The degradation half-time decreased from 5.53 days (treated with 10 microg x L(-1) VB12) to 3.08 days (treated with 100 microg x L(-1) VB12). The expression of cytochrome b6f complex iron-sulfur protein gene and dioxygenase gene showed significant correlation with PCB28-degradation by Nostoc PD-2. While the expression of iron-sulfur protein gene showed more significant correlation with PCB28-degradation. Results in this study indicated that adding VB12 could promote PCB28-degradation by Nostoc PD-2. Moreover, VB12 addition improved the PCB-degradation activity of Nostoc PD-2 at the gene level. The above conclusions could provide a new choice for developing efficient bioremediation technology for PCB-contaminated environment and a new insight into the PCB-biodegradation mechanism by Nostoc PD-2.

The Sb2O4:Yb3+, Tm3+ up-conversion luminescence powder with excellent physical, chemical stability and relative low phonon energy was synthesized by the high temperature solid-state reaction and its up-conversion luminescence property was investigated. Under the 980 nm excitation, infrared and blue up-conversion emissions centered at 800 and 480 nm were observed, which were assigned to the 1G4--3H6 and 3H4--3 He transitions of Tm2+, respectively. The influence of Yb3+ and Tm3+ concentration on the up-conversion emission property was also obtained. The up-conversion luminescence increases with increasing of Yb3+ and Tm3+ concentration. Additionally, the up-conversion luminescence mechanism was discussed based on the dependence of Tm3+ up-conversion luminescence on pump power. It is interesting that two photon excitation processes for blue and infrared emission were observed in the Sb2O04: Yb3+, Tm3+ powder under a 980 nm excitation. Based on the energy level diagram of Tma3 and Yb2+ ions, we think that two photons blue emission is contributed to the cooperation energy transfer between Tm"+ and Yb3+ ions. We believe that the Sbz04 : Yb3 , Tm2+ up-conversion luminescence powder will have potential application for new optical devices in up-conversion color displays, sensors, detection of infrared radiation, and lasers.

In this study, grass carp (Ctenopharyngodon idellus) lymphocytes were used as the vitro test object to demonstrate the joint effects of microcystins (MC-LR) and bacterial lipopolysaccharides (LPS) on fish immune system. The results showed that MC-LR and LPS in the single and combined exposure groups could both induce grass carp lymphocytes apoptosis with typical ladder-like DNA electrophoresis characteristics. However, comparing the apoptosis rate of the combined and single exposure groups, it was suggested that bacterial LPS could cooperate with MC-LR causing a higher rate of fish lymphocytes apoptosis (2.1 and 3.3-fold of that for the single exposure group I (MC-LR) and II (LPS), respectively), and there existed a significant dose-response relationship. The MC-LR cooperating with bacterial LPS decreased the activity of glutathione S-transferase (GST), increased the levels of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA), resulted in DNA damage and cell arrest in G0 phase, which inhibited cell proliferation and accelerated apoptosis. It was proved that MC-LR exacerbated fish immunotoxicity by collaborating with LPS, which had a serious adverse effect on aquaculture industry.

The aim of this study was to investigate the relatively frequencies of alleles in the HLA-C*04:01:01G group and to analyze their relations with HLA-A and -B loci. DNA samples previously typed as HLA-C*04:01:01G were sequentially selected. The sequences for exon 2 to 7 of the HLA-C locus were analyzed by polymerase chain reaction sequence-based typing(PCR-SBT). The HLA-A, -B, -DRB1 and -DQB1 loci were genotyped using PCR-SBT method. The results showed that 178 samples (94.2%) and 11 samples (5.8%) were assigned as HLA-C*04:01:01 and HLA-C*04:82 respectively among 189 samples previously typed as HLA-C*04:01:01G. 72 haplotypes associated with HLA-C*04:01:01 and C*04:82 were found, in which the frequencies of 26 haplotypes were over 0.0050. HLA-C*04:01:01 was strongly related with A*02:03, A*02:07, A*11:01, A*33:03, B*13:01, B*15:01, B*15:05, B*15:27, B*40:01, B*54:01 alleles, while HLA-C*04:82 was related with B*40:01. It is concluded that HLA-C*04:01:01 and HLA-C*04:82 alleles were confirmed in the HLA-C*04:01:01G group, which should be discriminated by the routine HLA genotyping.