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We have grown undoped, Si- and Mg-doped GaN epilayers using metalorganic chemical vapor deposition. The grown samples have electron Hall mobilities (carrier concentrations) of 798 cm2/V s (7×1016 cm−3) for undoped GaN and 287 cm2/V s (2.2×1018 cm−3) for Si-doped GaN. Mg-doped GaN shows a high hole concentration of 8×1017 cm−3 and a low resistivity of 0.8 Ω cm. When compared with undoped GaN, Si and Mg dopings increase the threading dislocation density in GaN films by one order and two orders, respectively. Besides, it was observed that the Mg doping causes an additional biaxial compressive stress of 0.095 GPa compared with both undoped and Si-doped GaN layers, which is due to the incorporation of large amount of Mg atoms (4–5×1019 cm−3).

The carbon incorporation into lattice sites in Si1−yCy epilayers and Si1−yCy/Si multiple quantum wells grown by molecular beam epitaxy was investigated as a function of growth temperature in the range of 350–650°C using Raman spectroscopy, double crystal X-ray diffraction (DCXD), and atomic force microscopy (AFM). The substitutional carbon concentration deduced from the simulation of DCXD results decreases with increasing growth temperature due to the strain relaxation process which occurred by the change of the growth mode from two-dimensional to three-dimensional island growth.

Thin layers of InGaN were grown by metalorganic chemical vapor deposition and characterized with atomic force microscopy and high-resolution transmission electron microscopy. InGaN deposited on GaN exhibits a Stranski-Krastanov growth mode, including 2D wetting layer and 3D self-assembled quantum dots. Besides, we observed that the formed InGaN nano-scale dots have a trapezoidal shape with a {1-102} facet with respect to (0002) surface. Visible spectral range from UV to green was easily obtained by changing InGaN quantum well thickness up to 2.3 nm.

We report the observation of the field-driven blue shift at near absorption edge in the photo-current response spectra of δ-doped Si n–i–p–i multiple quantum wells due to the widening of the effective energy gap. This phenomenon differs from the observed results in GaAs/AlGaAs and GeSi/Si superlattices, because the physical mechanisms of forming energy band in these superlattice samples are different. Our experimental results are interpreted satisfactorily by the theoretical calculation.

The dark current of five periods Si 0.76 Ge 0.24 (60 A)/Si(300 A) quantum wells grown at 600, 680, 760 and 850°C were measured at various temperatures and bias voltages. The dark current were determined by the thermalization of carriers at reverse and small forward bias, but controlled by the injection of carriers at large forward bias. At −5 V bias, deep levels D 1 and D 2 or their complex, D 1 D 2 dominate the dark current between 150 and 318 K, while deep levels D 3 and D 4 or their complex D 3 D 4 play an important role between 77 and 150 K. Strain induced defects can be favorably formed in the Si 1− x Ge x well or Si barrier region depending on the growth condition. At 5 V of bias, the temperature dependence of the dark current shows an exponential behavior which resembles the threshold current of a semiconductor laser, with the characteristic temperature increasing with growth temperature. The bias dependencies of activation energies exhibit a field induced dissociation of D 1 D 2 complex, change of properties of D 3 D 4 complex, and the recombination or thermal activation of injected holes.

Transmission electron microscopy (TEM) was utilized to investigate microstructures of heteroepitaxial SiC/Si films, grown from single-source precursors such as tetramethylsilane [TMS, Si(CH3)4], hexamethyldisilane [HMDS, Si2(CH3)6], and 1,3-disilabutane [1,3-DSB, H3SiCH2SiH2CH3]. In the case of TMS/H2 and HMDS/H2 samples, SiC/Si films grown at relatively high precursor concentration and/or low temperatures showed columnar grains with a high degree of epitaxial relationship with the Si substrate. Higher quality films with larger grains were observed in the case of high temperature and/or low precursor concentration samples, although a high density of interfacial voids was observed. Samples grown from pure 1,3-DSB at a low pressure showed high quality single crystalline films with few interfacial voids. It was suggested that the microstructural behavior of these films closely resembles that of the SiC films formed during the carbonization of Si surfaces by the pyrolysis of hydrocarbons, in which the nucleation rate of the film at the initial stage plays a key role. The improvement achieved during the 1,3-DSB growth is proposed to be due to the low growth pressure and the 1 : 1 ratio of Si and C associated with this precursor.

GaN epitaxial films are grown on c-plane sapphire substrates with CrN buffer. The GaN layers show high crystalline quality and smooth surface morphology without being cracked. Selective etching of CrN buffer is performed by wet etching using conventional Cr metal etchant, which results in success ful lift-off of GaN thick layers. We confirm that the crystalline quality of GaN does not change through the etching process. These results indicate that the chemical lift-off process using CrN buffer is promising for production of both freestanding GaN substrates and vertical-structure devices. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A high-quality zinc selenide (ZnSe) single crystal was grown in a two-stage vertical electric furnace by the Piper and Polich sublimation method with an asymmetric temperature profile around a peak temperature. The growth of the single crystal was optimized at the temperature difference of 13°C between the source and growth parts in the growth tube. The temperature difference was in good agreement with the calculated value of 135.018°C. The diffraction patterns shows that the single crystal exhibits a zinc blende structure with a lattice constant of 5.627 A. The measured carrier concentration and mobility of the as-grown ZnSe single crystal are 4.92×10 8 holes cm −3 and 4.40×10 3 cm 2 /V s at room temperature, respectively. We notice that the energy band gap obtained from photocurrent measurements follows Varshni's formula E g (T)=2.808 eV −(8.69×10 −4 eV/K ){T 2 /(T+330)} rather than a linear relationship E g (T)=2.83 eV −(8.0×10 −4 eV/K )T .

We generate amorphous Si1 − xGex alloys for various Ge compositions by the simulated quenching method using the first-principles molecular-dynamics approach. We find that dangling bonds at Ge sites dominate the local defect structures in a wide range of Ge compositions of x ≥ 0.15, although their backbonding states change with Ge composition. This is due to the minimization of strain energy by having dangling bonds at Ge sites in the network. By postulating that only dangling bonds contribute to the g-value, the calculated g-values are in excellent agreement with the observed ones.

The microwave dielectric characteristics of MNb2O6 compounds which are subcomponents of the complex perovskite A(B′ 1 3 B″ 2 3 )O3 have been investigated as a function of M ions. All MNb2O6 compounds have the columbite structure. Dielectric properties such as permittivity, dielectric loss, and temperature coefficient of resonant frequency are found to correlate strongly with the M ions. In particular, the temperature coefficient of the resonant frequency may be correlated to the unit-cell volume of MNb2O6. Among these compounds, ZnNb2O6 had very high quality factors. © 1997 Elsevier Science Ltd

The microwave dielectric characteristics and crystal structure of the Zn(NbxTa1−x)2O6 and Mg(NbxTa1−x)2O6 systems have been investigated. It was found that both systems exhibited a morphotropic phase transition. Based on the results it was suggested that permittivity and temperature coefficient of resonant frequency depend more on crystal structure rather than on chemical composition. It was also suggested that a two-phase mixture is better than a solid solution for achieving both high quality factor and good temperature stability.

The capacitance (C) of a GaAsAl0.3Ga0.7As quantum well infrared photodetector (QWIP) was measured as a function of temperature and bias voltage. Thermally generated electrons in the excited sub-band lead to the high capacitance because of the reduction of effective dielectric layer thickness as a result of the wave function extension to the barrier layer. Peaks and valleys in the capacitance-voltage (C-V) curves have been attributed to the on- and off-resonant states in QWIP. The formation and evolution of bias induced electric field domains (EFD's) were analyzed from the C-V line shapes, which depend on electron distributions in sub-bands, the resonant coupling between sub-bands in the neighboring wells, and the transport stability in QWIP. Fine structures in the capacitance-temperature (C-T) curves show that the formation of EFD's is thermally induced. We show the onset temperature of the capacitance can be used to determine the maximum operating temperature of a QWIP.

Photoluminescence (PL) measurements were carried out on strained In0.2Ga0.8AsGaAs quantum well structures. By analyzing the transition energies and linewidths as functions of temperature as well as the excitation intensity, we found that well width fluctuations are up to six monolayers depending upon the sample structure. PL peak energies and linewidths vary with temperature and the excitation intensity due to the change of the distribution ratio of energy levels generated by the structural disorder at the interfaces.

Several phase II/III trials of anti-insulin-like growth factor 1 receptor (IGF-1R) monoclonal antibodies (mAbs) have shown limited efficacy. The mechanisms of resistance to IGF-1R mAb-based therapies and clinically applicable strategies for overcoming drug resistance are still undefined.IGF-1R mAb cixutumumab efficacy, alone or in combination with Src inhibitors, was evaluated in 10 human head and neck squamous cell carcinoma (HNSCC) and six non-small cell lung cancer (NSCLC) cell lines in vitro in two- or three-dimensional culture systems and in vivo in cell line- or patient-derived xenograft tumors in athymic nude mice (n = 6-9 per group). Cixutumumab-induced changes in cell signaling and IGF-1 binding to integrin β3 were determined by Western or ligand blotting, immunoprecipitation, immunofluorescence, and cell adhesion analyses and enzyme-linked immunosorbent assay. Data were analyzed by the two-sided Student t test or one-way analysis of variance.Integrin β3-Src signaling cascade was activated by IGF-1 in HNSCC and NSCLC cells, when IGF-1 binding to IGF-1R was hampered by cixutumumab, resulting in Akt activation and cixutumumab resistance. Targeting integrin β3 or Src enhanced antitumor activity of cixutumumab in multiple cixutumumab-resistant cell lines and patient-derived tumors in vitro and in vivo. Mean tumor volume of mice cotreated with cixutumumab and integrin β3 siRNA was 133.7 mm(3) (95% confidence interval [CI] = 57.6 to 209.8 mm(3)) compared with those treated with cixutumumab (1472.5 mm(3); 95% CI = 1150.7 to 1794.3 mm(3); P.001) or integrin β3 siRNA (903.2 mm(3); 95% CI = 636.1 to 1170.3 mm(3); P.001) alone.Increased Src activation through integrin ανβ3 confers considerable resistance against anti-IGF-1R mAb-based therapies in HNSCC and NSCLC cells. Dual targeting of the IGF-1R pathway and collateral integrin β3-Src signaling module may override this resistance.

Chlorogenic acid, which belongs to the polyphenols, is an anti-oxidant and anti-obesity agent. In this study, we investigated the role of chlorogenic acid in inflammation. Anti-inflammatory effects of chlorogenic acid were examined in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages and BV2 microglial cells. We observed the level of various inflammation markers such as nitric oxide (NO), inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and chemokine (C-X-C motif) ligand 1 (CXCL1) under LPS treatment with or without chlorogenic acid. To clarify the specific effect of chlorogenic acid, we evaluated the adhesion activity of macrophages and ninjurin1 (Ninj1) expression level in macrophages. Finally, we confirmed the activation of the nuclear factor-κB (NF-κB) signaling pathway, which is one of the most important transcription factors in the inflammatory process. Chlorogenic acid significantly inhibited not only NO production but also the expression of COX-2 and iNOS, without any cytotoxicity. Chlorogenic acid also attenuated pro-inflammatory cytokines (including IL-1β and TNF-α) and other inflammation-related markers such as IL-6 in a dose-dependent manner. Additionally, endotoxin-induced adhesion of macrophages and the expression level of ninjurin1 (Ninj1) were decreased by chlorogenic acid. Finally, chlorogenic acid inhibited the nuclear translocation of NF-κB. Chlorogenic acid may be beneficial for the prevention and treatment of anti-inflammatory diseases.

In this study, we investigated the antitumor effects of deguelin in several human breast cancer cells in vitro and in vivo. Deguelin inhibited cell viability and the anchorage-dependent and anchorage-independent colony formation of triple-negative (MDA-MB-231 and MDA-MB-468) and triple-positive (MCF-7) breast cancer cells, and it significantly reduced the growth of MCF-7 cell xenograft tumors. The induction of apoptosis, inhibition of insulin-like growth factor-1 receptor (IGF-1R) signaling activation, and up-regulation of IGF-binding protein-3 (IGFBP-3) expression may be associated with deguelin-mediated antitumor effects. Our findings suggest a potential therapeutic use for deguelin in patients with triple-negative breast cancer and for those with breast cancers who are sensitive to endocrine- and HER2-targeted therapies.

3D IC integration is the latest technological breakthrough for maximizing its performance while reducing wiring lengths, interconnection latency, and power consumption. Through-silicon via (TSV) is an essential feature of the 3D IC integration. Filling high aspect ratio TSVs by the conductive materials can be a challenging task. Copper electrodepostion is often adopted due to its optimal electrical preoperties, simplicity, and cost-effectiveness. However, the coefficient of thermal expansion (CTE) of copper is much higher (16.7 ppm/℃) than that of silicon (2.3 ppm/℃). Therefore, the CTE mismatch between copper and silicon substrate can induce thermal stresses, which may lead to TSV protrusion and interfacial delamination. In previous studies, this is mostly managed via suitable heat treatment. This study however proposes a novel method for controlling TSV protrusion. Copper with JGB (Janus Green B, C30H31ClN6) concentration increases (and at the level of 0.2mM of JGB), while the sheet resistance decrease by 7% for the initial resistance. Here, the crystal growth is not observed that is due to impurity pinning or solute dragging effect at grain boundaries. This leads to the conclusion that controlling impurity contents may relieve stress of TSV overhang area. To prevent TSV protrusion, we also perform the same concentration split tests on TSV pattern wafers. Figure 1. EBSD IPF maps of Cu electrodeposit after annealing at 80 ℃ for 90 min with various JGB concentrations of (a) 0, (b) 0.01, (c) 0.03, (d) 0.1, (e) 0.2 and (f) 1 mM in the Cu plating bath. Figure 1

GaN based photoelectrode with a nanowire structure have been studied due to superior performance of water splitting ability. Self‐organized GaN nano‐rod on silicon has been demonstrated, and a direct growth via vapour–liquid–solid using metal particle as a catalyst has been reported. Nonowire structure has benefit with short minority carrier diffusion lengths and large surface-to-volume ratio. It allows minor carrier to easily reach to surface without recombination, so that water splitting ability could be increased. However, this structure has photocorrosion problem. For solving this problem, we covered graphene material on the tips of nanowires as a passivation layer. Graphene has been known to have excellent mechanical, thermal, optical, and electrical properties. For these reasons, we studied the photoelectrochemical water splitting properties of graphene coated GaN nanowire (graphene/GaN nanowire) photoelectrode. GaN nanowire sample without graphene was used for the reference. The GaN nanowire structures were grown on n-type Si(111) substrates using radio-frequency plasma-assisted molecular beam epitaxy. The graphene was grown by chemical vapor deposition method and exfoliated to surface of GaN nanowire. As a result, compared with non-coated GaN nanowire sample, the graphene/GaN nanowire phoeoelectrode showed higher photocurrent density. Also, we could know that it has much higher photocurrent stability. We will present the results and the reasons for higher efficiency and stability of this graphene coated GaN nanowire sample at this conference. Reference [1] Allon I. Hochbaum, and Peidong Yang, Chem. Rev., 110 (2010) 527–546 [2] B. AlOtaibi, M. Harati, S. Fan, S. Zhao, H. P. T. Nguyer, M. G. Kibiria, and Z. Mi, Nanotechnology, 24 (2013) 175401

Prior resting-state functional magnetic resonance imaging (fMRI) analyses have identified patterns of functional connectivity associated with hallucinations in schizophrenia (Sz). In this study, we performed an analysis of the mean amplitude of low-frequency fluctuations (ALFF) to compare resting state spontaneous low-frequency fluctuations in patients with Sz who report experiencing hallucinations impacting different sensory modalities. By exploring dynamics across 2 low-frequency passbands (slow-4 and slow-5), we assessed the impact of hallucination modality and frequency range on spatial ALFF variation. Drawing from a sample of Sz and healthy controls studied as part of the Functional Imaging Biomedical Informatics Research Network (FBIRN), we replicated prior findings showing that patients with Sz have decreased ALFF in the posterior brain in comparison to controls. Remarkably, we found that patients that endorsed visual hallucinations did not show this pattern of reduced ALFF in the back of the brain. These patients also had elevated ALFF in the left hippocampus in comparison to patients that endorsed auditory (but not visual) hallucinations. Moreover, left hippocampal ALFF across all the cases was related to reported hallucination severity in both the auditory and visual domains, and not overall positive symptoms. This supports the hypothesis that dynamic changes in the ALFF in the hippocampus underlie severity of hallucinations that impact different sensory modalities.

The expression of immunogenic markers after differentiation of umbilical cord blood (UCB)-derived mesenchymal stem cells (MSC) has been poorly investigated and requires extensive in vitro and in vivo testing for clinical application. The expression of human leukocyte antigen (HLA) classes on UCB-derived MSC was tested by Fluorescence-activated cell sorting analysis and immunocytochemical staining. The undifferentiated MSC were moderately positive for HLA-ABC, but almost completely negative for HLA-DR. The MSC differentiated to chondrocytes expressed neither HLA-ABC nor HLA-DR. The proliferation of MSC was not significantly affected by the allogeneic lymphocytes stimulated with concanavalin A. The responder lymphocytes showed no significant decrease in proliferation in the presence of the MSC, but the apoptosis rate of the lymphocytes was increased in the presence of MSC. Taken together, these findings indicate that UCB-derived MSC differentiated to chondrocytes expressed less HLA class I and no class II antigens. The MSC showed an immunomodulatory effect on the proliferation and apoptosis of allogeneic lymphocytes. These data suggest that the differentiated and undifferentiated allogeneic MSC derived from umbilical cord blood can be a useful candidate for allogeneic cell therapy and transplantation without a major risk of rejection.

Sixteen channels of 10-Gb/s signals were successfully transmitted over five spans of 80 km using gain-clamped semiconductor amplifiers as inline amplifiers in combination with distributed Raman fiber amplifiers. The combined amplifier had a gain of 20 dB and a noise figure of less than 2.7 dB. No penalty was observed when 15 out of 16 channels were dynamically add-dropped in the 400-km transmission system.

Light Detection and Ranging (LiDAR) data compression is a critical research field for data processing during past few years because of the large storage size. When LiDAR has small number of data points, the surface generation represented by interpolation methods may be inefficient. This paper presents a compression algorithm to simplify the LiDAR data set, which is constructed based on the quad-tree structure, for fast preprocessing step. The related theory and the methods to make it reality are discussed in detail respectively. Some conclusions were induced from tests: the method presented in this paper can provide multiple compression ratios based on needs, and guarantee the accuracy of LiDAR data for each case.

Two types of radioiodinated plasma driven antigens, heat-inactivated (125I-h-HBsAg) and formalin-inactivated HBsAg (125I-f-HBsAg) were investigated for the effect of immunoadjuvant, aluminium phosphate (AP) on pharmacokinetics, organ distribution and humoral immunity of differently inactivated hepatitis B surface antigens (HBsAg) in rats. As a result, most of h-HBsAg (90%) was retained and slowly eliminated from the injection site. The h-HBsAg was highly localized in regional lymph node (RLN), but resulted in low humoral immune response. On the other hand, f-HBsAg was less localized in the injection site and RLN, but mainly distributed into serum and liver (62.9 and 22.4%, respectively). However, both h-HBsAg and f-HBsAg slowly disappeared from the injection site with AP, resulting in the increased area under the amount-time curve (AUQ) of h-HBsAg and f-HBsAg in the injection site. Exposures of h-HBsAg and f-HBsAg in serum were increased (1.4 and 2.8 times increase in AUC, respectively) with AP. The RLN uptake of both antigens were dramatically increased (25 and 3.1 times increase in AUC, respectively) with higher humoral immune response. The antibody titres were also increased with AP. In conclusion, pharmacokinetics, organ distribution and humoral immunity of h-HBsAg were highly dependent on the inactivation method of antigen and the presence of immunoadjuvant such as AP.

Arbutin, which is found in the genus Arctostaphylos, is an anti-oxidant and a depigmenting agent. The present study was designed to validate the anti-inflammatory effect of arbutin.The anti-inflammatory properties of arbutin were studied using a lipopolysaccharide (LPS)-stimulated murine BV2 microglial cells model. As inflammatory parameters, the production of nitric oxide (NO), inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), monocyte chemoattractant protein-1 (MCP-1), and interleukin-6 (IL-6) were evaluated. We also examined the expression of ninjurin1 (Ninj1) and the adhesion activity of BV2 cells. Finally, we analyzed the activation of the nuclear factor-κB (NF-κB) signaling pathway.Arbutin suppressed LPS-induced production of NO and expression of iNOS and COX-2 in a dose-dependent manner without causing cellular toxicity. Arbutin also significantly reduced generation of proinflammatory cytokines, including IL-1β and TNF-α, and other inflammation-related genes such as MCP-1 and IL-6. Additionally, arbutin suppressed the adhesion activity of BV2 cells and the expression of an important adhesion molecule, Ninj1, in LPS-stimulated murine BV2 cells. Furthermore, arbutin inhibited nuclear translocation and the transcriptional activity of NF-κB.Taken together, our results suggest that arbutin might be useful for treating the inflammatory and deleterious effects of BV2 microglial cells activation in response to LPS stimulation.

Orthogonal space-time codes (OSTCs) have recently captivated considerable attention due to their properties of full diversity and low implementation complexity. In this paper, we derive effective use OSTCs for MIMO systems successfully. It has been calculated coding gain of the orthogonal ST code and fast ML decoding at the receiver can be decoded separately. This goal achieved by properly choosing the signal constellations and compare bit-error-rate (BER) to signal-to-noise ratio (SNR) of different QPSK and QAM techniques. Simulation results show that the obtained constellations outperform not only the conventional QAM constellation, but also other well-known constellations used for efficient data communications.

In this paper, we present a novel region growing method combined with mathematical morphology for scalp and skull extraction in T1-weighted brain MR images. First, a grayscale dilation operation is used in 2D brain MR image. Second, the scalp and skull portions are extracted by using a region growing method with intensity threshold. Third, the scalp and skull mask is optimized by using a closing operation. Finally, the mask model is reconstructed in three-dimensional space. The results of the proposed method and the region growing with intensity threshold on MRI data acquired from five persons were compared with manual segmentation. The mean similarity index for the scalp and skull extracted regions was equal to 96.2% in the proposed method. The experimental results indicate that the proposed method can extracted the scalp and skull accurately and effectively.

A real-time background segmentation system has already proposed based on two methods Principle Components Analysis (PCA) and Single Gaussian Model (SGM). But PCA based method is required to calculate of decomposition and for this reasons time consumption is vast. On the other hand SGM based foreground segmentation model which is reliably deals with lighting changes, detects repetitive motion from clutter and long-term scene changes. This paper presents a method consists with two methods extended PCA (EPCA) and SGM. An adaptive strategy is used to integrate two methods. We adopt the adaptively incremental eigenspace model to build the intensity information for each pixel. Weng designed Candidate Covariance-Free Incremental PCA (CCIPCA) method, which does not need decomposition. Moreover, it is also simpler and faster than other proposed incremental PCA (IPCA) methods. Shadow removal using adaptive filter and post-processing techniques are used in a proposed method. Therefore, as the proposed algorithm does not require decomposition so this method is faster with PCA and SGM based foreground extraction method. Experimental results represent that this proposed model is robust to noise and illumination change due to inheriting eigenbackground and Gaussian's model advantages to improve the segmentation results.

Since women with climacteric syndrome have significantly lower serum levels of estradiol and other related hormones, hormone replacement therapies (HRT) such as estrogen are needed to lessen symptoms. However, HRT can often cause severe adverse effects that include many cancers and stroke. Therefore, new and novel approaches to relieve climacteric syndrome still need to be developed. The aim of this study was to identify biologically active peptides from calf spleen that are responsible for stimulating biosynthesis of steroid hormone and to explore the potential of isolated peptides as therapeutic agents for menopausal syndrome. The reverse phase HPLC system was used to isolate active compounds from calf spleen extract, a cell culture system was used to screen the activity of stimulating hormone secretion, and Matrix-Assisted Laser Desorption/Ionization (MALDI) mass spectrometry was used for molecular weight determination. In the present study, two calf steroidogenic peptides, CSP-1 (MW; 4.655 kDa) and CSP-2 (MW; 8.331 kDa), were isolated and identified from calf spleen and may be putative climacteric syndrome therapeutic agents.

To develop the long acting nifedipine oral delivery with bioavailability enhancement, a nifedipine dry elixir (NDE) containing nifedipine ethanol solution in dextrin shell was prepared using a spray-dryer, and then coated nifedipine dry elixir (CNDE) was prepared by coating NDE with Eudragit acrylic resin. The physical characteristics and bioavailability of NDE and CNDE were evaluated, and then compared to those of nifedipine powder. NDE and CNDE, which were spherical in shape, had about 6.64 and 8.68-8.75 μm of geometric mean diameters, respectively. The amount of nifedipine dissolved from NDE for 60 min increased about 7- and 40-fold compared to nifedipine powder in pH 1.2 simulated gastric fluid and pH 6.8 simulated intestinal fluid, respectively. Nifedipine released from CNDE was retarded in both dissolution media compared with that from NDE. After oral administration of NDE, the C(max) and AUC(0→8h) of nifedipine in rat increased about 13- and 7-fold, respectively, and the Tmax of nifedipine was reduced significantly compared with those after oral administration of nifedipine powder alone. The AUC(0→8h) and T(max) of nifedipine in CNDE increased markedly and the C(max) of nifedipine in CNDE was significantly reduced compared to those in NDE. It is concluded that CNDE, which could lower the initial burst-out plasma concentration and maintain the plasma level of nifedipine over a longer period with bioavailability enhancement, might be one of potential alternatives to the marketed long acting oral delivery system for nifedipine.

Mechanical properties of suspended quasi-one-dimensional polymer nanostructures were investigated using atomic force microscopy (AFM). A recently developed new acid-free etch method combined with electron beam lithography was used to fabricate suspended polypyrrole (PPy) nanotubes and helical polyacetylene (HPA) nanofibres. The elastic modulus of each suspended structure was obtained by AFM force-distance measurements. The estimated modulus value of the PPy nanotube (HPA nanofibre) was 0.96 GPa (0.5 GPa). Using this acid-free method, all-organic flexible NEMS devices can be fabricated in the future.

It is well known that the energy level of a transition metal (TM) such as manganese is tied to the vacuum level rather than to a particular band extreme in semiconductors. Therefore, TM can be used as a common reference energy level in all the semiconductors. We have investigated for the first time the photoluminescence spectrum of Mn-doped In0.5Ga0.5P/GaAs heterojunction and by using the Mn acceptor level in photoluminescence (PL) spectra, the fractional band offsets Qc and Qv for the In0.5Ga0.5P/GaAs heterojunction are determined as 0.63 and 0.37, respectively.

Spatially and spectrally resolved photoluminescence of InGaN/GaN quantum wells grown by metalorganic chemical vapor deposition is studied with near-field scanning optical microscopy (NSOM) and transmission electron microscopy (TEM). High-spatial-resolution NSOM images show bright blue quantum well emission around V defects and yellow emission inside the defects. TEM data suggest that the spatial distribution of blue luminescence is partly due to dislocation gettering by V defects. The yellow emission is attributed to the Ga vacancy-impurity complexes trapped inside V defects.

Spatially and spectrally resolved photoluminescence (PL) from InGaN/GaN quantum wells is obtained using near-field scanning optical microscopy (NSOM). Samples displaying high macroscopic PL intensity revealed nonuniform intensity and linewidth but nearly uniform peak position. It suggests that the contrast in the NSOM image reflects nonuniform distribution of dislocations or defects which act as nonradiative recombination centers. The formation of quantum dots with size of 30±25 nm and their size-dependent interaction with dislocations were observed in plan-view transmission electron microscopy. It is likely that the high luminescence efficiency is due to the efficient localization of excitons in high-density quantum dots located in regions with fewer dislocations.

This article presents performance analysis of multiple channel noise cancellation by beam forming algorithm depending on the variation of arrival of angles of the interference signal. In this article we examined that the effectiveness of the desired signal by the different arrival of angles of interference signals. The variation of the arrival angles of the interference signal considered to with intervals and the desired signal arrival angle is . The desired signal and the optimized multi-layer perception (MLP) were used to calculate the correlation values at different angle. We also used the Back propagation algorithm as learning rule for MLP and improving our signal quality. This involves a desired signal whilst removing any noise or interference signals which may come from different sources [1][2].

A 4-year-old beagle had intermittent vomiting and weight loss for 1 month. On plain radiography, an approximately 3.5-cm, radiopaque, linear foreign body was identified in the region of the liver. On ultrasonography, a hyperechoic linear structure with reverberation was identified in the left lobe or quadrate lobe. On computed tomography(CT), a thin hyperattenuating material consistent with a metallic foreign body was identified just medial to the gall bladder. Removal of the foreign body was performed without complications. We present a rare case in which a metallic foreign body was embedded in the liver asymptomatically and found incidentally during a clinical examination performed to ascertain the cause of clinical signs.

Under hypoxia, mouse embryonic stem cells (mESCs) lose their self-renewal activity and display an early differentiated morphology mediated by the hypoxia-inducible factor-1 alpha (HIF-1 alpha). Previous studies have demonstrated that PKC-delta is activated by hypoxia and increases the protein stability and transcriptional activity of HIF-1 alpha in human cancer cells. Furthermore, activation of PKC-delta mediates cardiac differentiation of ESCs and hematopoietic stem cells. However, the role of PKC-delta in hypoxia-induced early differentiation of mESCs remains largely unknown. Here, we show the inhibition of PKC-delta activity prevents the early differentiation of mESCs under hypoxia using PKC-delta inhibitors, GF 109203X and rottlerin. Reduction of PKC-delta activity under hypoxia effectively decreased HIF-1 alpha protein levels and substantially recovered the expression of LIF-specific receptor (LIFR) and phosphorylated-STAT3 in mESCs. Furthermore, PKC-delta inhibitors aid to sustain the expression of self-renewal markers and suppress the expression of early differentiation markers in mESCs under hypoxia. Taken together, these results suggest that PKC-delta inhibitors block the early differentiation of mESCs via destabilization of HIF-1 alpha under hypoxia.

Nerve injury induced protein 1, Ninj1 (Ninjurin1) is a cell surface protein that is induced by nerve injury and promotes axonal growth in the peripheral nervous system. However, the function of Ninj1 in the vascular system and central nervous system (CNS) is incompletely understood. Here we review recent studies that have shed further light on the role and regulation of Ninj1 in vascular remodeling and inflammation. Increasing evidence suggests that Ninj1 mediates cell communication and enhances the entry, migration, and activity of leukocytes such as monocytes and macrophages in developmental processes and inflammatory responses. Moreover, our recent studies show that Ninj1 regulates close interaction between leukocytes and vascular endothelial cells in vascular remodeling and inflamed CNS. Additionally, Ninj1 enhances the apoptosis-inducing activity of leukocytes and is cleaved by MMPs, resulting in loss of adhesion during tissue remodeling. The collective data described here show that Ninj1 is required for the entry, adhesion, activation, and movement of leukocytes during tissue remodeling and might be a potential therapeutic target to regulate the adhesion and trafficking of leukocytes in inflammation and leukocyte-mediated diseases such as multiple sclerosis, diabetic retinopathy, and neuropathy.

The annotation of functional neuroimaging results for data sharing and reuse is particularly challenging, due to the diversity of terminologies of neuroanatomical structures and cortical parcellation schemes. To address this challenge, we extended the Foundational Model of Anatomy Ontology (FMA) to include cytoarchitectural, Brodmann area labels, and a morphological cortical labeling scheme (e.g., the part of Brodmann area 6 in the left precentral gyrus). This representation was also used to augment the neuroanatomical axis of RadLex, the ontology for clinical imaging. The resulting neuroanatomical ontology contains explicit relationships indicating which brain regions are “part of” which other regions, across cytoarchitectural and morphological labeling schemas. We annotated a large functional neuroimaging dataset with terms from the ontology and applied a reasoning engine to analyze this dataset in conjunction with the ontology, and achieved successful inferences from the most specific level (e.g., how many subjects showed activation in a sub-part of the middle frontal gyrus) to more general (how many activations were found in areas connected via a known white matter tract?). In summary, we have produced a neuroanatomical ontology that harmonizes several different terminologies of neuroanatomical structures and cortical parcellation schemes. This neuranatomical ontology is publicly available as a view of FMA at the Bioportal website at http://rest.bioontology.org/bioportal/ontologies/download/10005. The ontological encoding of anatomic knowledge can be exploited by computer reasoning engines to make inferences about neuroanatomical relationships described in imaging datasets using different terminologies. This approach could ultimately enable knowledge discovery from large, distributed fMRI studies or medical record mining.

Photoconductivity and optical absorption measurements were employed to analyze deep levels in undoped n-type GaN films grown on sapphire substrate by metalorganic chemical vapor deposition. At room temperature, the photoconductivity measurement exhibits a broad level at around 1.90 eV. Similarly, the optical absorption spectrum shows a deep level located at 1.87 eV within the band gap, which is best described by a transition from a donor charge-transfer level to the conduction band, according to Lucovsky theory. A persistent photoconductivity whose behavior is distinctive from that of previously reported work for n- or p-type GaN epitaxial films was observed. The photocurrent quenching and decreased dark current in the persistent photoconductivity effect suggest that metastable electron states are formed in the band gap to trap electrons which tunnel out the potential barrier with long recovery time.

Medical image segmentation is a complex and challenging task due to the intrinsic nature of the images. Segmentation of magnetic resonance imaging (MRI) is widely used in medical area. One of common clustering algorithms is Fuzzy c-means (FCM) for segmentation of MR images. However MR images normally significant noise by the impact of principles of imaging, equipment and environment, which can lead to serious inaccuracies with segmentation. Based on the FCM clustering algorithm, an improved segmentation technique is proposed in this paper. The Sigma filter principle has been applied to change the neighbor pixels of targets. The efficacy of the proposed algorithm is demonstrated by comparison with FCM algorithm in visual evaluation and quantitative evaluation.

EGb 761 is a standardized extract of Gingko biloba that exerts protective effects against ischemic brain injury. This study investigated whether EGb 761 modulates the neuroprotective effects through Akt and its downstream targets, Bad and FKHR. Adult male rats were treated with EGb 761 (100 mg/kg) or vehicle prior to middle cerebral artery occlusion (MCAO). Brains were collected 24 hours after MCAO and infarct volumes were analyzed. EGb 761 significantly reduced infarct volume. Potential activation was mearsured by phosphorylation of Akt at Ser473, Bad at Ser136, and FKHR at Ser256 using Western blot analysis. EGb 761 prevented the injury-induced decrease of pAkt and its down stream targets, pBad and pFKHR. Furthermore, EGb 761 prevented the injury-induced increase of cleaved caspase-3 levels. In conclusion, this study suggests that EGb 761 prevents cell death due to brain injury and that EGb 761 protection is affected by preventing the injury-induce decrease of Akt phosphorylation.

Developmental tissues go through regression, remodeling, and apoptosis. In these processes, macrophages phagocytize dead cells and induce apoptosis directly. In hyaloid vascular system (HVS), macrophages induce apoptosis of vascular endothelial cells (VECs) by cooperation between the Wnt and angiopoietin (Ang) pathways through cell-cell interaction. However, it remains unclear how macrophages are activated and interact with VECs. Here we show that Ninjurin1 (nerve injury-induced protein; Ninj1) was temporally increased in macrophages during regression of HVS and these Ninj1-expressing macrophages closely interacted with hyaloid VECs. Systemic neutralization using an anti-Ninj1 antibody resulted in the delay of HVS regression in vivo. We also found that Ninj1 increased cell-cell and cell-matrix adhesion of macrophages. Furthermore, Ninj1 stimulated the expression of Wnt7b in macrophages and the conditioned media from Ninj1-overexpressing macrophages (Ninj1-CM) decreased Ang1 and increased Ang2 in pericytes, which consequently switched hyaloid VEC fate from survival to death. Collectively, these findings suggest that macrophages express Ninj1 to increase the death signal through cell-cell interaction and raise the possibility that Ninj1 may act similarly in other developmental regression mediated by macrophages.

A one-step approach to obtain high quality free-standing GaN (FS-GaN) substrates by hydride vapor phase epitaxy (HVPE) has been developed. FS-GaN substrates were fabricated by the control of void density at the GaN-Al2O3 interface using a novel evaporable buffer layer (EBL). The EBL consisted of GaN-crystallites imbedded in NH4Cl films, and was grown by lowering the growth temperature down to 450 °C under NH3 and HCl ambient in the HVPE system. The NH4Cl was evaporated during heating up for high temperature growth of GaN (HT-GaN), resulting in high void density, which plays a key role in the self-separation of thick HT-GaN during cooling down. The FS-GaN substrate showed smooth surface morphology without cracks. The full width at half maximum values of (0002) and (10-10) ω-rocking curves from a 500 μm-thick FS-GaN were 104 and 70 arcsec, respectively. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Well aligned ZnO nanowall arrays with submicron pitch were grown on a periodically polarity-inverted ZnO template using a carbothermal reduction process. Under the conditions of a highly dense Au catalyst for increasing nucleation sites, ZnO nanowalls with a thickness of 126 +/- 10 nm, an average height of 3.4 microm, and a length of about 10 mm were formed on the template. The nanowalls were only grown on a Zn-polar surface due to a different growth mode with an O-polar surface. The results of x-ray diffraction and photoluminescence (PL) measurements revealed a single crystalline, vertical alignment on the template, and a large surface to volume ratio of the ZnO nanowalls.

Light Detection and Ranging (LiDAR) data has been used to model earth surface in an easy and economic way. As technology is developed the application of LiDAR data is also widely expanded to various areas, such as hydrological modeling, telecommunication service and urban planning. Finding accurate road networks is one of the common applications from massive LiDAR data. A novel algorithm to extract road points has been developed based on both the intensity and height information of data points. First the robustness of the sequential algorithm has been verified with real data points. Then a parallel algorithm has been developed by applying smart area partitioning. The performance of a parallel algorithm showed us a close linear speedup with the use of up to four processors. Experimental results from the parallel algorithm are presented in this paper in detail and demonstrate the robustness of the proposed method.

Semiconductor nanostructures are very promising for future photonic devices owing to their unique optical properties which are quite dependent on their morphology. We report lasing characteristics of ZnO nanostructures with various morphologies including nano-wire, nano-taper, porous nano-wires, and nano pencils. Single crystalline ZnO nanostructures are synthesized using chemical vapor transport and condensation (CVTC) or aqueous reaction. Nonlinear optical properties of nanostructures are investigated. Optical pumping of ZnO nanostructures is carried out using micro photoluminescence (u-PL) system with the frequency-tripled output (355nm) of a Nd:YAG laser (repetition rate of 10 Hz and 6 ns pulse width). We observe an enhancement in laser emission intensity as the morphology of the nanowire changes the facet structure to porous structure. The variation of optical properties can be explained in terms of modified emission rate in ZnO nanowires with large surface area.

We previously showed that estradiol prevents neuronal cell death through the activation of Akt and its downstream targets Bad and FKHR. This study investigated whether estradiol modulates the survival pathway through other downstream targets of Akt, including mammalian target of rapamycin (mTOR) and p70S6 kinase. It is known that mTOR is a downstream target of Akt and a central regulator of protein synthesis, cell growth, and cell cycle progression. Adult female rats were ovariectomied and treated with estradiol prior to middle cerebral artery occlusion (MCAO). Brains were collected 24h after MCAO and infarct volumes were analyzed. We confirmed that estradiol significantly reduces infarct volume and decreases the number of positive cells for TUNEL staining in the cerebral cortex. Brain injury-induced a decrease in phospho-mTOR and phospho-p70S6 kinase. Estradiol prevented the injury-induced decrease in Akt activation and phosphorylation of mTOR and p70S6 kinases, and the subsequent decrease in S6 phosphorylation. Our findings suggest that estradiol plays a potent protective role against brain injury by preventing the injury-induced decrease of mTOR and p70S6 kinase phosphorylation.