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Over the past few decades, ammonia (NH3) is commonly used in the petrochemical and semiconductor industries. Exposed to NH3 is dangerous to life and continuous monitoring of NH3 becomes vital. Sensitive and stable ammonia gas sensors with low-power consumption have gained increasing attention. This study uses a through-silicon via (TSV) technology and atomic layer deposition (ALD) to fabricate a three-dimensional (3D) TSV-structured room temperature TiO2 gas sensor. For various NH3 concentrations, the sensor response for the 3D TiO2 gas sensor increased if the NH3 concentration is increased. In terms of the stability and the reproducibility of the 3D room temperature TiO2 NH3 gas sensor at 10 ppm NH3 gas, the sensor response is about 9.35% on average, with an inaccuracy of 3 gas. This gas sensor of good stability, reproducibility, and selectivity with low power consumption can be used in various applications.

Background & Aims The diagnostic accuracy of a novel serological panel (BioFibroScore®) to predict hepatic fibrosis in patients with chronic hepatitis C virus (HCV) infection is unknown. Methods Three markers of BioFibroScore®, including urokinase plasminogen activator (uPA), matrix metalloproteinase-9 (MMP-9), and beta-2 microglobulin (β2M), were retrospectively evaluated in 635 HCV-infected patients who received percutaneous liver biopsy and FibroScan®. The formula of BioFibroScore® to predict the severity of hepatic fibrosis was developed by Adaboost algorithm. The diagnostic accuracy of hepatic fibrosis was assessed both for BioFibroScore® and FibroScan®, taking METAVIR fibrosis score as the reference standard. Results uPA and β2M were positively and MMP-9 was negatively associated with the severity of hepatic fibrosis. Thirty-five (5.5%) patients had failed FibroScan® assessment. By Adaboost model for BioFibroScore® and the established reference ranges for FibroScan®, 85.7% and 89.0% of the patients had an identical result for F0-1, F2, F3 and F4, as compared to liver biopsy. The concordance rate between BioFibroScore® and FibroScan® was 80.7%. BioFibroScore® overestimated and underestimated the stage of hepatic fibrosis in 8.3% and 6.0% patients, and most patients had one stage error. Among patients with failed FibroScan® assessment, 82.9% of them were correctly diagnosed by BioFibroScore®. Bootstrap analysis for BioFibroScore® showed the diagnostic accuracy was 80.9-88.4%. Conclusions BioFibroScore® is accurate to assess the stage of hepatic fibrosis in HCV-infected patients. Applying this noninvasive test can substantially reduce the need for invasive liver biopsy and can play a role for fibrosis evaluation when FibroScan® assessment was unavailable or unreliable.

A green energy device with a CuInGaSe2 (CIGS) photovoltaic (PV) cell covered with a passive light-trapping structure (ZnO nanowires (NWs)) and connected to an active energy-harvesting device (thermoelectric generator (TEG)) is presented. The efficiency of the ZnO NWs/CIGS PV device obtained using a deposition temperature of 550 °C and Cd-free processes reaches 16.5%. The series-connected CIGS PV cell with a TEG had a record-high efficiency of 22% at a cool-side temperature (Tc) below 5 °C. The open-circuit voltage (Voc) of the hybrid CIGS PV/TEG device was increased from 0.64 to 0.85 V. This technology has potential for high-efficiency energy-harvesting applications. Copyright © 2014 John Wiley & Sons, Ltd.

Metastasis is the major factor affecting patient survival in ovarian cancer. However, its molecular mechanisms remain unclear. Our study used isogenic pairs of low- and high-invasive ovarian cancer cell lines to demonstrate the downregulation of miRNA-138 in the highly invasive cells, and its functioning as an inhibitor of cell migration and invasion. An orthotopic xenograft mouse model further demonstrated that the expression of miRNA-138 inhibited ovarian cancer metastasis to other organs. Results indicated that miR-138 directly targeted SRY-related high mobility group box 4 (SOX4) and hypoxia-inducible factor-1α (HIF-1α), and overexpression of SOX4 and HIF-1α effectively reversed the miR-138-mediated suppression of cell invasion. Epidermal growth factor receptor acted as the downstream molecule of SOX4 by way of direct transcriptional control, whereas Slug was the downstream molecule of HIF-1α by way of proteasome-mediated degradation. Analysis of human ovarian tumors further revealed downregulation of miR-138 and upregulation of SOX4 in late-stage tumors. Patients with miR-138(low)/SOX(high) signature are predominant in late stage and tend to have malignant phenotypes including lymph nodes metastasis, larger ascites volume and higher tumor grade. Our study demonstrates the role and clinical relevance of miR-138 in ovarian cancer cell invasion and metastasis, providing a potential therapeutic strategy for suppression of ovarian cancer metastasis by targeting SOX4 and HIF-1α pathways.

Glucocorticoids are widely used in conjunction with chemotherapy for ovarian cancer to prevent hypersensitivity reactions. Here we reveal a novel role for glucocorticoids in the inhibition of ovarian cancer metastasis. Glucocorticoid treatments induce the expression of miR-708, leading to the suppression of Rap1B, which result in the reduction of integrin-mediated focal adhesion formation, inhibition of ovarian cancer cell migration/invasion and impaired abdominal metastasis in an orthotopic xenograft mouse model. Restoring Rap1B expression reverts glucocorticoid-miR-708 cascade-mediated suppression of ovarian cancer cell invasion and metastasis. Clinically, low miR-708 and high Rap1B are found in late-state ovarian tumours, as compared with normal, and patients with high miR-708 show significantly better survival. Overall, our findings reveal an opportunity for glucocorticoids and their downstream mediators, miR-708 or Rap1B, as therapeutic modalities against metastatic ovarian epithelial cancer., Glucocorticoids show promise for the treatment of ovarian cancer. Here the authors show that glucocorticoids transcriptionally induce the tumour suppressor miR-708, which is downregulated in ovarian cancer, especially in late stages and metastatic tumours.

e23130Background: Determination of HER2 status before taking therapeutic regimens plays an essential role in breast cancer. Immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) ...

e15612Background: The Pre-S region(nucleotides 2854-155) locates at the S gene(encodeing the surface protein) of HBV DNA genome and consists of the Pre-S1 and Pre-S2 domains. A meta-analysis with m...

Metastasis is the major factor affecting patient survival in ovarian cancer. However, its molecular mechanisms remain unclear. Our study used isogenic pairs of low- and high-invasive ovarian cancer cell lines to demonstrate the downregulation of miRNA-138 in the highly invasive cells, and its functioning as an inhibitor of cell migration and invasion. An orthotopic xenograft mouse model further demonstrated that the expression of miRNA-138 inhibited ovarian cancer metastasis to other organs. Results indicated that miR-138 directly targeted SRY-related high mobility group box 4 (SOX4) and hypoxia-inducible factor-1α (HIF-1α), and overexpression of SOX4 and HIF-1α effectively reversed the miR-138-mediated suppression of cell invasion. Epidermal growth factor receptor acted as the downstream molecule of SOX4 by way of direct transcriptional control, whereas Slug was the downstream molecule of HIF-1α by way of proteasome-mediated degradation. Analysis of human ovarian tumors further revealed downregulation of miR-138 and upregulation of SOX4 in late-stage tumors. Patients with miR-138(low)/SOX(high) signature are predominant in late stage and tend to have malignant phenotypes including lymph nodes metastasis, larger ascites volume and higher tumor grade. Our study demonstrates the role and clinical relevance of miR-138 in ovarian cancer cell invasion and metastasis, providing a potential therapeutic strategy for suppression of ovarian cancer metastasis by targeting SOX4 and HIF-1α pathways.

CuInGaSe 2 (CIGS) thin-film has successfully grown at low temperature 400 °C for bifacial solar cells and TFTs without degrading the silicon solar cell on the other side. The efficiency of CIGS solar cells reached 6.3% and 11% at 400 and 500 °C, respectively, by sodium-free and Cd-free (n-type ZnS buffer layer used) green technologies. Texturing technique has been introduced here on Si not only to relieve the sodium-free impact on CIGS-crystallization but also to enhance the adhesion between CIGS solar cells and underneath substrate. CIGS TFTs are reported first time and revealed a record-high hole-mobility of 0.22 cm2/V-s. Hybrid CIGS solar cells/TFTs are uniformly formed on 6″ wafers, simultaneously powered with silicon solar cells.

Si nanowire (NW)-based photovoltaic devices were fabricated using NWs grown at various temperatures. It was found that the average length and average diameter of the NWs increased as the growth temperature was increased from 450°C to 620°C. It was also found that the NWs became sparser with increasing growth temperature. The reflectance spectra and I-V characteristics indicate that the average reflectances were about 9%, 15%, and 18% and that the photovoltaic conversion efficiencies were 4.1%, 2.33%, and 1.87% for Si NWs grown at 450°C, 550°C, and 620°C, respectively. The experiment results show that the largest fill factor (74%) and external quantum efficiency (40%) (for a wavelength of 740 nm) were achieved for Si NWs grown at 450°C.

This paper presents a novel single stage power converter for photovoltaic energy conversion application. The presented power converter consists of a boost type resonant circuit from which both DC and AC outputs are generated. The DC output is used to charge batteries and the AC output is applied for lighting purpose. A mixed maximum power point tracking algorithm is realized by using the boost characteristic of the converter and thus resulting in a single stage converter. The analysis and design of the converter is presented is this paper and a prototype converter based on microcontroller PIC 18F452 with rated power 90W is constructed for demonstration. Various experimental measurements of the prototype converter are performed and the results verify the theoretical analysis and design.

In this paper, large grain polycrystalline silicon films on glass substrates have been fabricated at a low temperature of 350°C. The amorphous silicon (a-Si:H) films deposited by plasma-enhanced chemical vapor (PECVD) were transformed to polysilicon films by using nano-aluminum induced crystallization (AIC) at a low temperature. Effect of the annealing time on the grain size and crystalline phase were discussed. The polycrystalline silicon films were characterized by using XRD, Raman and SEM. The surface morphology, sheet resistance and the crystallization mechanism were also discussed. Polycrystalline silicon films with grain sizes larger than 3 microns were obtained in this study at 350°C.

Interstitial flow in and around tumor tissue affects the mechanical microenvironment to modulate tumor cell growth and metastasis. We investigated the roles of flow-induced shear stress in modulating cell cycle distribution in four tumor cell lines and the underlying mechanisms. In all four cell lines, incubation under static conditions for 24 or 48 h led to G 0 /G 1 arrest; in contrast, shear stress (12 dynes/cm 2 ) induced G 2 /M arrest. The molecular basis of the shear effect was analyzed, and the presentation on molecular mechanism is focused on human MG63 osteosarcoma cells. Shear stress induced increased expressions of cyclin B1 and p21 CIP1 and decreased expressions of cyclins A, D1, and E, cyclin-dependent protein kinases (Cdk)-1, -2, -4, and -6, and p27 KIP1 as well as a decrease in Cdk1 activity. Using specific antibodies and small interfering RNA, we found that the shear-induced G 2 /M arrest and corresponding changes in G 2 /M regulatory protein expression and activity were mediated by α v β 3 and β 1 integrins through bone morphogenetic protein receptor type IA-specific Smad1 and Smad5. Shear stress also down-regulated runt-related transcription factor 2 (Runx2) binding activity and osteocalcin and alkaline phosphatase expressions in MG63 cells; these responses were mediated by α v β 3 and β 1 integrins through Smad5. Our findings provide insights into the mechanism by which shear stress induces G 2 /M arrest in tumor cells and inhibits cell differentiation and demonstrate the importance of mechanical microenvironment in modulating molecular signaling, gene expression, cell cycle, and functions in tumor cells.

e11619 Background: HER2 gene is amplified and/or overexpressed in approximate 15% to 20% of primary breast cancers. Knowing the HER2 status is therefore essential for making right decision. Quantit...

Zirconium tin titanate (Zr 0.8 Sn 0.2 TiO 4 , ZST) thin films were deposited along the (100) index on a p-type Si substrate by a modified sol-gel method. The effects of film thickness on the crystalline structure and electrical property of the ZST films were investigated. X-ray diffraction confirmed a pronounced preferred orientation in thinner films and a polycrystalline structure in thicker films. The relationship between the leakage current densities and different crystalline structures is discussed. The leakage current densities of the prepared ZST films were below 10 -7 A/cm 2 at 3 MV/cm, which were sufficiently small to be a candidate for application in dynamic random-access memory (DRAM).