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We showed well-aligned zinc oxide (ZnO) nanorod arrays synthesized using hydrothermal method at atmospheric pressure. The influence of fabrication conditions such as Zn2+/hexamethylentriamin concentration ratio, and growth temperature on the formation of ZnO nanorods was investigated. Scanning Electron Microscope (SEM) images and X-ray Diffraction (XRD) analysis were used to confirm the single crystal of ZnO nanorods, which showed wurtzite structure with growth direction of [0001] (the c-axis). Photoluminescence (PL) measurements of ZnO nanorods revealed an intense ultraviolet peak at 388.5 nm (3.19 eV) at room temperature. The results showed that the ZnO seed layers had strong influence on the growth of vertically aligned ZnO nanorods. The gas sensor based on ZnO nanorod arrays had the most selectivity with n-butanol gas (within 2 surveyed gas: ethanol and n-butanol) and showed a higher sensitivity of 222, fast response time of 15 seconds, recovery time of 110 seconds and lower operating temperature of 200-250 °C than the sensor based on the ZnO film in the same detecting conditions.

In this study, a recorded high open-circuit voltage (Voc) of 1.61 V and fill factor (FF) of 76.65% of a-Si:H p-i-n/heterojunction with intrinsic thin layer (HIT)-type multi-junction solar cells were achieved using grain size enlargement within the p-type μc-Si:H layer in a p-type μc-Si:H/n-type a-Si:H tunneling recombination junction (TRJ) layer. The p-type μc-Si:H layer's conductivity increased from 1.74 × 10−4 to 0.1 S cm−1 as the film's crystallinity increased from 41.5% to 67.5%. The a-Si:H p-i-n/HIT-type multi-junction solar cells also benefited from the tuning up crystalline p-type μc-Si:H layer, showing the increase of Voc and FF from 1.5 V and 49.88% to 1.61 V and 76.65%, respectively; while the short-circuit current density (9.38 ± 0.2 mA cm−2) did not change significantly. These are the highest Voc and FF values achieved in a-Si:H p-i-n/HIT-type multi-junction solar cells, recently. From dark current-voltage analysis, it was deduced that the enhanced crystalline films could assist in suppressing carrier interference in the TRJ layer, thus reduces electric field distortion and mitigates recombination in the device. In summary, an enhanced crystalline p-type μc-Si:H layer could be a viable option for ensuring an excellent TRJ layer, thus achieved high efficiency of inorganic/c-Si tandem solar cells. Using optimal condition with crystallinity of 74.1%, the photovoltaic parameters of the device yield Voc, Jsc and FF of 1.51 V, 13.01 mA cm−2 and 71.45%, which in turned giving an efficiency of 14.04% for a-SiGe:H p-i-n/HIT-type tandem solar cell.

Relation between magnetoresistance and magnetization reversal in thin multilayered IrMn–Co/Pd films deposited both on planar and nanoporous substrates is in focus of the present work. Magnetic anisotropy, exchange coupling and mechanisms of magnetic resistivity are discussed.

We report novel polymyxin analogues with improved antibacterial in vitro potency against polymyxin resistant recent clinical isolates of Acinetobacter baumannii and Pseudomonas aeruginosa . In addition, a human renal cell in vitro assay (hRPTEC) was used to inform structure-toxicity relationships and further differentiate analogues. Replacement of the Dab-3 residue with a Dap-3 in combination with a relatively polar 6-oxo-1-phenyl-1,6-dihydropyridine-3-carbonyl side chain as a fatty acyl replacement yielded analogue 5x, which demonstrated an improved in vitro antimicrobial and renal cytotoxicity profiles relative to polymyxin B (PMB). However, in vivo PK/PD comparison of 5x and PMB in a murine neutropenic thigh model against P. aeruginosa strains with matched MICs showed that 5x was inferior to PMB in vivo, suggesting a lack of improved therapeutic index in spite of apparent in vitro advantages.

A novel series of 3- O -carbamoyl erythromycin A derived analogs, labeled carbamolides, with activity versus resistant bacterial isolates of staphylococci (including macrolide and oxazolidinone resistant strains) and streptococci are reported. An ( R )-2-aryl substituent on a pyrrolidine carbamate appeared to be critical for achieving potency against resistant strains. Crystal structures showed a distinct aromatic interaction between the ( R )-2-aryl (3-pyridyl for 4d ) substituent on the pyrrolidine and G2484 (G2505, Escherichia coli ) of the Deinococcus radiodurans 50S ribosome (3.2 A resolution).

A phytochemical study of n-hexane and ethyl acetate extracts of Pinus dalatensis Ferré leaves led to the isolation of 11 compounds, including one caryolane sesquiterpenoid (1), five labdane diterpenoids (2, 3, 4, 5, 6), one serratane triterpenoid (7), one diacylated flavonoid glucoside (8), one stilbenoid (9) and two sterols (10, 11). The structural characterisation of the isolated compounds was elucidated by spectroscopic data and comparison with the literature report on the chemical constituents from Pinus dalatensis Ferré. Futhermore, three compounds 1, 4 and 6 were obtained for the first time from the genus Pinus. Besides, compounds (2, 3, 5, 8, 9) were also subjected to cytotoxicity effect on SK-LU-1, MCF-7 and Hep-G2 cell lines, but only compound 9 expressed activities with IC50 values of 141.22, 127.81 and 166.84 μM, respectively.

The effect of low-temperature annealing treatment for various durations on the stability of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors was investigated. By this treatment, IGZO TFTs showed enhanced electrical characteristics and better stability under positive gate bias stress with increasing annealing time up to 18,000 s. For all VG stresses at different annealing times, the experimentally measured threshold voltage shift (ΔVth) as a function of stress time was precisely modeled with a stretched-exponential function. ΔVth was generated by carrier trapping, not by defect creation. It was verified that the decrease of interface trap state density (Nit) and free carriers resulted in the decrease of ΔVth with increasing annealing time. However, the characteristic trapping time of the carriers increased up to 5.3 × 103 s with increasing annealing time to 7,200 s and then decreased, implying that the interface quality between active layer/insulator was deteriorated with further annealing. In this study, successful fabrication of IGZO TFTs by post treatment with optimized duration is demonstrated for flexible display applications.

a-IGZO films were deposited on Si substrates by d.c sputtering technique with various working power densities ( p d ) in the range of 0.74–2.22 W/cm 2 . The correlation between material properties and their effects on electrical stability of a-IGZO thin-film transistor (TFTs) was studied as a function of p d . At a p d of 1.72 W/cm 2 a-IGZO film had smoothest surface roughness (0.309 nm) with In-rich and Ga-poor cation compositions as a channel. This structurally ordered TFTs exhibited a high field effect mobility of 9.14 cm 2 /Vs, a sub-threshold swing (S.S.) of 0.566 V/dec, and an on–off ratio of 10 7 . Additionally, the V th shift in hysteresis loop is almost eliminated. It was shown that the densification of the a-IGZO film resulted in the reduction of its interface trap density (1.83 × 10 12 cm −2 ), which contributes for the improvement in the electrical and thermal stability.

Mesenchymal stem cells (MSCs) have been shown to attenuate pulmonary damage induced by bleomycin-based anticancer treatments, but the influence of bleomycin on the stem cells themselves remains largely unknown. Here, we demonstrate that human bone marrow-derived MSCs are relatively sensitive to bleomycin exposure compared to adult fibroblasts. MSCs revealed increased levels of apoptosis after bleomycin treatment, while cellular morphology, stem cell surface marker expression and the ability for adhesion and migration remained unchanged. Bleomycin treatment also resulted in a reduced adipogenic differentiation potential of these stem cells. MSCs were found to efficiently repair DNA double strand breaks induced by bleomycin, mostly through non-homologous end joining repair. Low mRNA and protein expression levels of the inactivating enzyme bleomycin hydrolase were detected in MSCs that may contribute to the observed bleomycin-sensitive phenotype of these cells. The sensitivity of MSCs against bleomycin needs to be taken into consideration for ongoing and future treatment protocols investigating these stem cells as a potential treatment option for bleomycin-induced pulmonary damage in the clinic.

Microvesicles (MVs) derived from mesenchymal stem cells showed the ability to alter the cell phenotype and function. We previously demonstrated that type 2 diabetic adipose tissue-derived mesenchymal stem cells (dAT-MSCs) increase in cell aggregation and adhesion in vitro and impair wound healing in vivo. However, the characterization and function of MVs derived from human non-diabetic AT-MSCs (nAT-MSCs) remain unknown. In this study, we characterized nAT-MSC-derived MVs and their function after the transfection of dAT-MSCs with MVs using the scratch assay and a flap mouse model. We found that human nAT-MSC-derived MVs expressed MSC-surface markers and improved dAT-MSC functions by altering the expression of genes associated with cell migration, survival, inflammation, and angiogenesis as well as miR29c and miR150. Remarkably, the transfection of dAT-MSCs with nAT-MSC-derived MVs improved their migration ability in vitro and wound healing ability in a flap mouse model. These results demonstrate a promising opportunity to modify the function of dAT-MSCs for therapeutic stem cell application in diabetic patients.

The prevalence of type 2 diabetes mellitus (T2DM), which leads to diabetic complications, has been increasing worldwide. The possible applications of T2DM-derived stem cells in cell therapy are limited because their characteristics are still not fully understood. In this study, we characterized adipose tissue-derived mesenchymal stem cells (AT-MSCs) from diabetic patients (dAT-MSCs) and found that insulin receptor substrate-1 (IRS-1) was highly phosphorylated at serine 636/639 in dAT-MSCs. Moreover, we found that early growth response factor-1 (EGR-1) and its target genes of PTEN and GGPS1 were highly expressed in dAT-MSCs in comparison to healthy donor-derived AT-MSCs (nAT-MSCs). We observed impaired wound healing after the injection of dAT-MSCs in the ischemic flap mouse model. The expressions of EGR-1 and its target genes were diminished by small hairpin RNA-targeted EGR-1 (shEGR-1) and treatment with a mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) inhibitor (PD98059). Importantly, dAT-MSCs with shEGR-1 were able to restore the wound healing ability in the mouse model. Interestingly, under hypoxic conditions, hypoxia-inducible factor-1α (HIF-1α) can bind to the EGR-1 promoter in dAT-MSCs, but not in nAT-MSCs. Together, these results demonstrate that the expression of EGR-1 was upregulated in dAT-MSCs through two pathways: the main regulatory pathway is the MAPK/ERK pathway, the other is mediated by HIF-1α through direct transcriptional activation at the promoter region of the EGR1 gene. Our study suggests that dAT-MSCs may contribute to microvascular damage and delay wound healing through the overexpression of EGR-1. Interrupting the expression of EGR-1 in dAT-MSCs may be a useful treatment for chronic wounds in diabetic patients.

Process development and the multikilogram synthesis of a novel azetidinyl ketolide antibiotic is described. Starting with clarithromycin, the eight-step synthesis features several telescoped operations and direct isolations, which results in a significant improvement in throughput and a major reduction in solvent usage and waste stream volume over the first scale-up campaign. Particular highlights of this effort include the development of an efficient synthesis of 3-hydroxy-1,5-naphthyridine-4-carbaldehyde via a Skraup process and engineering a robust final API synthesis. We also discovered a crystalline monotosylate salt that addressed significant formulation and degradation issues experienced when using the noncrystalline freebase.

Welding or heat treatment of steel structures generate important heat gradients. These heat gradients are generally very localized and involve local dilations that lead to the appearance of residual strain and stress fields. These fields play a very important role in fatigue life prediction of structures. In addition, thermal cycles induced by welding or heat treatment operations can generate phase transformations within the material. The work presented in this paper describes an anisothermal model for steel where thermomechanical and metallurgical aspects are taken into account. In the proposed model, the thermomechanical behavior of each phase is treated independently and the macroscopic behavior is obtained using a Reuss model. In order to quantify the importance of the TRansformation Induced Plasticity (TRIP: plastic deformation due to the variation of the proportion of phases under applied stress) as well as viscosity, two descriptions are presented: first, the phases are assumed to be elastoplastic; second, the low-temperature phases are considered as elastoplastic whereas the high-temperature phase is assumed to be viscoplastic. For each description the influence of TRIP is considered by comparing results obtained with or without TRIP. These models have been implemented into the numerical code COMSOL Multiphysics by developing new modules capable of simulating phase transformation and inelastic deformation. Numerical simulations show good agreement with experimental data. Moreover, it is shown that taking into account TRIP and assigning for each phase an appropriate behavior improve the predictions of residual displacements and stresses.

ZnO and Sn doped ZnO (ZnO:Sn) thin films at various doping concentrations from 1 to 10 at.% were prepared by the sol–gel method for an ethanol sensing application. The Sn doping significantly influenced the film growth, grain size and response of the films. The XRD patterns showed that the hexagonal wurtzite structure of the ZnO film was retained even after the Sn doping. The crystallite grain sizes of the ZnO:Sn thin films at 0, 2 and 4 at.% were estimated by using the typical Scherrer's equation. The crystalline quality of the films at 6, 8 and 10 at.% of Sn was degenerated. Typical FESEM images demonstrated the different morphologies for the ZnO:Sn thin films at various Sn concentrations; many pores of various dimensions were observed depending on the doping level. A TEM analysis of the ZnO:Sn thin films at 0, 2 and 4 at.% was performed to verify the grain size. The optimum Sn doping level of ZnO:Sn thin film for ethanol sensing was estimated to be 4 at.%. The 4 at.% sample obtained the highest response to ethanol vapor in the 10–400 ppm level range at a low operating temperature of 250 °C. The sensing mechanism was explained by a variation in the sensitivity model from a neck–grain-boundary controlled sensitivity to a neck-controlled sensitivity. Our work demonstrates the ability to reduce the working temperature as well as to increase the response of ZnO thin film based gas sensors to detect ethanol, which would be of great merit for commercialized applications.

AIM To determine the variation in caesarean section rates among immigrant populations. BACKGROUND Australia is one of the most multicultural in the world and is also among those with the highest caesarean section rates. DESIGN Secondary data analysis. METHODS Routinely collected data from a Local Heath District between 2011 and 2015 were analysed. Women were categorized into regional groups based on country of birth. Obstetrical risk was classified using the Robson classification. RESULTS/FINDINGS In total 48 711 women gave birth, of whom 64.0% were born overseas; 13 966 had a caesarean section (28.7%). South and Central Asia women had a high number of caesarean sections (n = 4139; 29.6% of all caesarean sections), a high overall adjusted caesarean section rate (31.4%; 95% CI, 30.5%-32.3%), and consistently high caesarean section rates among women with single cephalic term pregnancy without a previous caesarean section. High adjusted caesarean section rates were seen among South East Asia women with nulliparous, single cephalic, term pregnancy, and spontaneous labour. Demographic and clinical characteristics explained 83.5% of the variation in overall caesarean section rates between country of birth and 21.8% to 100% depending on Robson group. CONCLUSIONS Caesarean section rates varied by country of birth and within some Robson groups. The studied factors had various effects on the variation in caesarean section rates between country of birth and Robson groups.

Mesenchymal stem cells (MSCs) aid the regeneration of tissues damaged by treatment with cisplatin. However, the effects of this cytotoxic drug on the stem cells have been largely unknown. Here we demonstrate that human bone marrow-derived MSCs are relatively resistant to cisplatin treatment and show resistance levels comparable to these of differentiated fibroblasts. Cisplatin did not affect cellular morphology, adhesion or induction of apoptosis in MSCs. The potential for differentiation was preserved after exposure to cisplatin and established MSC surface markers were observed to be stably expressed irrespective of cisplatin treatment. Cytoskeletal rearrangements and high expression levels of individual heat shock proteins were detected in MSCs and may be partly responsible for the observed cisplatin resistance. The cisplatin-resistant phenotype of human MSCs supports the concept of further investigating these stem cells as a potential treatment option for cisplatin-induced tissue damage.

The objective was to identify factors associated with any use of antenatal care (ANC) gestational age at entry to ANC number of visits and overall ANC utilization in the three provinces of Long an Ben tre and Quang ngai. The Vietnam-Australia Primary Health Care Project conducted cross-sectional surveys in 1998-1999. Data from 1335 eligible women were available for analysis. Explanatory variables were selected using the Andersen Health Seeking Behavior Model and analyzed using multivariate regression techniques. External environment predisposing characteristics and need which existed before contact with ANC providers were most related to using any ANC and gestational age at entry to ANC. However ANC services provided to women and personal health care during pregnancy which could have resulted from initial contact with ANC providers were most related to continuation of ANC visits and overall ANC utilization. Significant variability in the use of ANC existed between provinces and between subsets of women in each province. To have more women who attend ANC and attend early promotion should be targeted at high-risk groups of women. However to improve the number of ANC visits and overall utilization the quality of ANC services should be improved. (authors)

Background Inhibition of cellular topoisomerases has been established as an effective way of treating certain cancers, albeit with often high levels of toxicity to the bone marrow. While the involvement of mesenchymal stem cells (MSCs) in bone marrow homeostasis and regeneration has been well established, the effects of topoisomerase-inhibiting anticancer agents remain largely unknown. Materials and Methods Human bone marrow MSCs were treated with topoisomerase I inhibitor irinotecan or topoisomerase II inhibitor etoposide, and survival and apoptosis levels were measured. The influence of topoisomerase inhibition on cellular morphology, adhesion and migration potential and the ability to differentiate was assessed. Additionally, the role of individual DNA double-strand break repair pathways in MSCs was investigated as a potential cellular mechanism of resistance to topoisomerase inhibitors. Results Human bone marrow MSCs were found relatively resistant to topoisomerase I and II inhibitors and show survival levels comparable to these of differentiated fibroblasts. Treatment with irinotecan or etoposide did not significantly influence cellular adhesion, migratory ability, surface marker expression or induction of apoptosis in human MSCs. The ability to differentiate was found preserved in MSCs after exposure to high doses of irinotecan or etoposide. MSCs were able to efficiently repair DNA double-strand breaks induced by topoisomerase inhibitors both by non-homologous end joining and homologous recombination pathways. Conclusion Our data demonstrate a topoisomerase-resistant phenotype of human MSCs that may at least in part be due to the stem cells' ability to efficiently remove DNA damage caused by these anticancer agents. The observed resistance of MSCs warrants further investigation of these cells as a potential therapeutic option for treating topoisomerase inhibitor-induced bone marrow damage.

BACKGROUND: WHO recommends screening for TB and evaluation for isoniazid preventive therapy (IPT) based on evidence that they reduce TB-related morbidity and mortality among HIV-infected persons. In Vietnam an IPT pilot was implemented in two provinces; TB screening treatment and outcomes were evaluated to inform the adoption and scale-up of IPT. METHODS: During April 2008 to March 2010 eligible HIV-infected persons aged >15 years with no previous or current TB treatment alcohol abuse or liver disease were screened for TB. If TB disease was ruled out based on symptoms chest x-rays and sputum smears isoniazid was administered for 9 months. RESULTS: Among 1281 HIV-infected persons who received initial eligibility screening 520 were referred to and evaluated at district TB clinics for TB disease or IPT eligibility. Active TB was diagnosed in 17 patients and all were started on treatment. Of 520 patients evaluated 416 (80.0%) initiated IPT: 382 (91.8%) completed IPT 17 (4.1%) stopped treatment 8 (1.9%) died 3 (0.7%) developed TB during IPT and 6 (1.4%) had unknown outcomes. No severe adverse events were reported. CONCLUSIONS: IPT treatment completion was high; no serious complications occurred. Improving and expanding intensified case-finding and IPT should be considered in Vietnam. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

International audience; To identify the proteins associated with the RNA polymerase III (Pol III) machinery in exponentially growing yeast cells, we developed our own tandem chromatin affinity purification procedure (TChAP) after in vivo cross-link, allowing a reproducible and good recovery of the protein bait and its associated partners. In contrast to TFIIIA that could only be purified as a free protein, this protocol allows us to capture free Pol III together with Pol III bound on its target genes. Transcription factors, elongation factors, RNA-associated proteins and proteins involved in Pol III biogenesis were identified by mass spectrometry. Interestingly, the presence of all the TFIIIB subunits found associated with Pol III together with the absence of TFIIIC and chromatin factors including histones suggest that DNA-bound Pol III purified using TChAP is mainly engaged in transcription reinitiation.

Sub1 and Maf1 exert an opposite effect on RNA polymerase III transcriptioninterfering with different steps of the transcription cycle. In this study, we presentevidence that Sub1 and Maf1 also exhibit an opposite role on yeast chronologicallife span. First, cells lacking Sub1 need more time than wild type to exit from restingand this lag in re-proliferation is correlated with a delay in transcriptionalreactivation. Second, our data show that the capacity of the cells to properlyestablish a quiescent state is impaired in the absence of Sub1 resulting in apremature death that is dependent on the Ras/PKA and Tor1/Sch9 signallingpathways. On the other hand, we show that maf1D cells are long-lived mutantsuggesting a connection between Pol III transcription and yeast longevity. Introduction In its natural environment, the budding yeast Saccharomyces cerevisiae spendsmost of its life in a quiescent state where it can maintain both viability and thecapacity to re-enter the proliferation cycle upon the addition of a carbon source.The length of time a non-dividing population of cells maintains viability definesits chronological life span (CLS). For years now, yeast CLS provides a fruitfulmodel for aging research and many progress have been made to understand themechanisms regulating the cell quiescence cycle, including the entry intoquiescence, the maintenance of viability and the capacity to re-proliferate. Anumber of dramatic morphological, physiological and biochemical changes [1,2]