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Enhanced oxygen vacancy (VO) has been designated as an effective strategy to prepare high-performance MnO2 nanocatalysts for the oxidation of volatile organic compounds (VOC) for thereof unbalanced electronic structure, and rapid electron transfer which may even reduce the reaction temperature down to room temperature. Herein, the effects of the VO on the catalytic performance of nano-sized MnO2 were discussed by classifying the VO into surface-anchored and bulk-involved ones. Currently used introducing and modulating methods for VO including elemental doping, energetic particle bombardment, atmosphere heat treatment, mechanical chemistry, and redox methods are detailly reviewed. Corresponding regulating mechanisms for VO are expounded. Commonly used characterization methods including ESR, XPS, HRTEM, and UV-vis are reviewed. Furtherly, the unveiled question which is highly expected to be answered on VO of MnO2 nanocatalysts is proposed. The purpose of this review is to present the current status of research on MnO2 nanoparticles and to provide researchers with basic research ideas. [ABSTRACT FROM AUTHOR]

The fuel tank of the advanced heavy launch vehicle is made of 2219 aluminum alloy with a thickness of 18 mm. Friction stir welding (FSW) technology is used to achieve the welding of the fuel tank. The increase of thickness directly affects welding temperature field, which ultimately affects the welding quality. At present, the temperature distribution law of FSW thick 2219 aluminum alloy is still blank, which is a bottleneck to ensure high welding quality. In this paper, a temperature field measurement and analyses system based on K-type thermocouple and LabVIEW for friction stir welding is developed first. Then experiments are carried out and the temperature data in welding and thickness directions are measured and the temperature law is analyzed. The comparison of temperature distribution of FSW thick and thin 2219 aluminum alloy is made, and the influence of welding thickness on the temperature field is studied. Based on temperature field, weld strength and microstructure, the influence of different process parameters on welding quality is explored. The research results lay a foundation for optimization of the welding process parameters and realization of constant temperature control of FSW. [ABSTRACT FROM AUTHOR]

The severe electric and thermal environments may cause localized deterioration of the contact behavior of thermoelectric devices. The contact responses of the thermoelectricity under the joint effect of the finite size and the friction are analyzed. The law of the Coulomb friction is adopted. The obtained Fredholm kernel functions reveal the influence of the thickness and the friction. The known Jacobi polynomials are employed to discretize the obtained singular integral equation. The effects of the thermoelectric loadings (the total electric current and the total energy flux), friction coefficient, the thermoelectric strip thickness, and the elastic and thermoelectric material constants on the distribution of the normal traction and the surface in-plane stress are demonstrated in detail. The smaller thermal expansion coefficient and shear modulus will contribute to the lower stress concentration at both contact edges. The surface in-plane tensile stress behind the trailing edge can be alleviated as the thermoelectric strip becomes thinner. [ABSTRACT FROM AUTHOR]

Background: Residual stress often generates during preparation, processing and use of silicon carbide (SiC) single crystal, which seriously affects the quality and service life of materials. Objective: This work aimed at evaluating the stress states in 6H-SiC single crystal wafers with different crystallographic orientations. Methods: The principle of determining the stress state of the hexagonal crystal system material through a multiple regression method was derived by modifying the related theory. Then the in-plane residual stress states of 6H-SiC samples grown along the [0001], 10 1 ¯ 0 and 11 2 ¯ 0 orientations were calculated, respectively. And the effect of the number of diffraction planes on the stress measurement results was studied. Finally, the stress results of SiC-6H materials grown in different crystallographic orientations were compared. Results: We found that the plane stress errors were gradually decreased with increase of the number of crystallographic planes, and were much lower than the ones estimated when the stress-free interplanar spacing was known; The residual stress states in single-crystal 6H-SiC of different crystallographic orientations were significantly different. Single-crystal 6H-SiC with 11 2 ¯ 0 growth direction had the smallest stress values, which was associated with the primary slip system {0001} ⟨ 11 2 ¯ 0 ⟩ . Conclusions: The improved methodology based on the multiple regression analysis can be applied to the stress measurement of single-crystal 6H-SiC. At least 6 planes should be used for stress detection to ensure the accuracy of residual stress results. Crystallographic orientation significantly influences the in-plane residual stress state in silicon carbide single crystal. [ABSTRACT FROM AUTHOR]

Eu3+/Tb3+-co-doped CaWO4 phosphors were synthesized by a simple green co-precipitation process. The structure of the samples was investigated by X-ray diffraction. The photoluminescence spectra and fluorescence decay lifetimes of the samples were measured to investigate the luminescence properties. We analyzed the energy transfer process between Eu3+- and Tb3+-doped CaWO4. As the Tb3+ to Eu3+ energy transfer process was confirmed, Eu3+- and Tb3+-co-doped CaWO4 phosphors showed a color-tunable emission from green to red under a 365-nm UV lamp. [ABSTRACT FROM AUTHOR]

Based on the design and preparation of the electrically assisted drawing die, the electric-assisted deep-drawn tests were carried out on high-strength steel plates with different strengths to study the electroplastic effect on high-strength steel drawing. The temperature distribution, macro-morphology, and hardness variation of deep-drawing workpieces undergone different electrical parameters were analyzed. The results showed that the Joule heat generated by the electrically assisted drawing die on the sample was symmetrically distributed along the center of the circular sheet, and the electrical pulse heat effect had little effect on the temperature rise of sheets (same material) with different strength levels. The introduction of pulse current could improve the forming performance of high-strength steel to a certain extent, as well as enhance its deep-drawing deformation ability. The hardness of the work-piece increased after it was deep-drawn. The Joule heat generated by the pulse current did not cause changes in the microstructure of the high-strength steel. The electroplastic effect improved the mechanical properties of the work-piece while increasing the formability of the high-strength steel plates. [ABSTRACT FROM AUTHOR]

A fast triple-parameter extremum seeking method is applied for jet control based on the pioneering work of Gelbert et al. (J Process Control 22(4):700, 2012). The simultaneous adaptation of three input parameters takes less time than the single-input adaptation of each parameter combined. The key enablers are phase-shifted sinusoids for the input each of which is evaluated by an extended Kalman filter (EKF). An acceleration of the adaption is obtained by a combined EKF coupling the output to all inputs. The method is illustrated for an analytical optimization problem and experimentally demonstrated for a turbulent jet mixing control. The considered Reynolds numbers Re D based on the jet exit diameter and velocity are 5700, 8000 and 13,300. The main jet is manipulated by a pulsed radially injected minijet which is varied by a mass flow controller and an electromagnetic valve up to high frequencies. The mixing performance is characterized by the centerline jet decay rate and monitored by a hot-wire sensor five diameters downstream at the end of the potential core. The proposed triple-parameter extremum seeking method optimizes the actuation mass flow ratio, frequency and duty cycle. The decay rate increases 11-fold from the unforced reference value of 0.05 to the optimal actuation level of 0.56. The reproducibility is demonstrated with various initial actuation parameters. Moreover, the adaptive control robustly tracks the optimal open-loop actuation for varying Re D ; the optimal decay rate remains unchanged given the mass flow rate, frequency and duty cycle are optimized. The unforced and actuated flow are investigated with hot wires and visualizations. The three-input ES significantly outperforms a two-parameter optimization for the same configuration in multiple respects (Wu et al. in AIAA J 56(4):1463, 2018): First, the jet decay rate is 8 % faster. Second, the convergence time for three parameters is only 25 % of the adaptation period of two parameters when Re D is varied. Finally, the current steady-state error is 45 % less than that of the two-parameter optimization. We expect the proposed triple-parameter extremum seeking to be applicable for a large range of flow control experiments. [ABSTRACT FROM AUTHOR]

The experimental identification of contact stress is important in many areas. In this paper, we present an inverse method for identifying the stress distribution on non-conforming contact interface based on local displacement measurements. A mechanical model is established to formulate the relationship between the contact stress and the displacement field near the interface. An optical method, named segmentation-aided digital image correlation is utilized to measure the near-field displacement. The contact stress is then inversed by finding the optimal model that best matches the measurements. Three model parameters, i.e., the contact center, contact length and maximum contact stress, are identified through an optimization procedure. The parameters are initialized by an image processing method and then iteratively refined by minimizing the discrepancy between the model predictions and the measured displacements. Both simulated and real-world experiments are conducted and the results verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Background: In England, 'fast-track' (also known as 'two-week wait') general practitioner referrals for suspected cancer in symptomatic patients are used to shorten diagnostic intervals and are supported by clinical guidelines. However, the use of the fast-track pathway may vary for different patient groups.Methods: We examined data from 669 220 patients with 35 cancers diagnosed in 2006-2010 following either fast-track or 'routine' primary-to-secondary care referrals using 'Routes to Diagnosis' data. We estimated the proportion of fast-track referrals by sociodemographic characteristic and cancer site and used logistic regression to estimate respective crude and adjusted odds ratios. We additionally explored whether sociodemographic associations varied by cancer.Results: There were large variations in the odds of fast-track referral by cancer (P<0.001). Patients with testicular and breast cancer were most likely to have been diagnosed after a fast-track referral (adjusted odds ratios 2.73 and 2.35, respectively, using rectal cancer as reference); whereas patients with brain cancer and leukaemias least likely (adjusted odds ratios 0.05 and 0.09, respectively, for brain cancer and acute myeloid leukaemia). There were sex, age and deprivation differences in the odds of fast-track referral (P<0.013) that varied in their size and direction for patients with different cancers (P<0.001). For example, fast-track referrals were least likely in younger women with endometrial cancer and in older men with testicular cancer.Conclusions: Fast-track referrals are less likely for cancers characterised by nonspecific presenting symptoms and patients belonging to low cancer incidence demographic groups. Interventions beyond clinical guidelines for 'alarm' symptoms are needed to improve diagnostic timeliness. [ABSTRACT FROM AUTHOR]

The inexpensive cost and high manufacture efficient metal wire and arc additive manufacturing (WAAM) system was designed in this work. Its application potential was evaluated from the three aspects of formability, microstructures, and mechanical properties. By using compulsory cooling solution implemented in the open-source WAAM system, the complex-shaped metal parts were deposited completely with no obvious defects, such as cracks, pores, or incomplete fusion. The properties of the WAAM part were evaluated by optical microscopy (OM), scanning electron microscopy (SEM), microhardness, and microtensile test. The results indicate that the formability of metal parts fabricated by the open-source WAAM system was improved by using compulsory cooling solution. The microstructures of the WAAM part are exhibited as granular structure which consisted of the granular ferrite and the residual austenite interspersed with a little pearlite in the intermediate zone. And the average ferrite grain size of non-overlapping layer is relatively smaller than that of overlapping layer. The specimen perpendicular to the building direction exhibits a better mechanical property. [ABSTRACT FROM AUTHOR]

The closed-loop control of a turbulent round air jet is experimentally investigated based on two unsteady minijets, with a view to enhancing jet mixing. The two minijets are placed at diametrically opposite locations upstream of the nozzle exit. The open-loop control experiments are first performed. Given the mass flow rate ratio C of the minijets to that of the main jet, the decay rate $$\overline{K}$$ of jet centerline mean velocity exhibits a maximum at the frequency ratio f / f ≈ 1.0, where f and f are the excitation frequency of minijets and the preferred mode frequency of the natural main jet, respectively. An extremum-seeking feedback control has been developed to achieve autonomously the optimal control performance. It has been found that, given C , this closed-loop control technique may obtain automatically and rapidly the optimal value of f and the desired or maximum $$\overline{K}$$ , as achieved in the open-loop control. This control technique is robust and adaptable when the Reynolds number and initial excitation frequency are changed separately. A flow-physics-based feedback control strategy has also been investigated, which could achieve the optimal control performance automatically with a shorter convergence time than the extremum-seeking control, not robust though. [ABSTRACT FROM AUTHOR]

Modifiers of response to glucose, insulin and potassium (GIK) infusion may affect clinical outcomes in acute coronary syndromes (ACS). In an Immediate Myocardial Metabolic Enhancement During Initial Assessment And Treatment In Emergency Care (IMMEDIATE) trial's sub-study (n=318), we explored effects of 132 634 genetic variants on plasma glucose and potassium response to 12-h GIK infusion. Associations between metabolite-associated variants and infarct size (n=84) were assessed. The 'G' allele of rs12641551, near ACSL1, as well as the 'A' allele of XPO4 rs2585897 were associated with a differential glucose response (P for 2 degrees of freedom test, P2df⩽4.75 × 10-7) and infarct size with GIK (P2df<0.05). Variants within or near TAS1R3, LCA5, DNAH5, PTPRG, MAGI1, PTCSC3, STRADA, AKAP12, ARFGEF2, ADCYAP1, SETX, NDRG4 and ABCB11 modified glucose response, and near CSF1/AHCYL1 potassium response (P2df⩽4.26 × 10−7), but not outcomes. Gene variants may modify glucose and potassium response to GIK infusion, contributing to cardiovascular outcomes in ACS. [ABSTRACT FROM AUTHOR]

Applying the operator method, general solutions for dynamic governing equations involving anisotropic piezoelectric materials are derived. Based on the general solutions, a rigid solid with a sinusoidal surface moving along the surface of anisotropic piezoelectric materials is concerned. Dual series equations are obtained and solved analytically. Then, the electro-elastic fields are determined in series forms. A full contact problem leads to more simple forms. Numerical analysis is performed for the anisotropic piezoelectric material $${0^{\circ }}$$ Graphite-epoxy, in which an illustrative example concerning the vertical mechanical displacement on the surface is displayed to validate the present approach. Results demonstrate that the contact behavior is considerably affected by both the velocity and material properties. [ABSTRACT FROM AUTHOR]

In this paper, we propose segmentation-aided digital image correlation (SA-DIC) for measuring the deformation near the interface between two contact bodies. Conventional DIC assumes that the shape function correctly warps a square subset from the reference image to the deformed image. When the subset is close to the contact interface, it contains pixels from the two contact bodies and the background if clearance is present. The displacement field in the subset is greatly complicated by the induced discontinuity and mismatches the shape function. To resolve this problem, SA-DIC automatically segments the image pixels into three categories: the two contact bodies and the invalid area. By using complementary speckle patterns, the contact interface exhibits a sharp intensity transition and it is extracted by edge detection. The background pixels are identified from the difference of the reference image pair captured with distinct background. Based on the image segmentation, only the pixels belonging to the same category are included in the subset. Their displacements are homogeneous and thus well characterized by the shape function used in DIC. Both simulated and real-world experiments are carried out to evaluate the proposed method and compare with conventional DIC. The results show that SA-DIC is able to measure the localized deformation due to the contact, while conventional DIC generates large errors near the contact interface and falsely locates the most deformed areas. [ABSTRACT FROM AUTHOR]

RNA interference (RNAi) is a promising tool for cancer therapy, but its delivery strategy is a major challenge for its application. Oncolytic herpes simplex virus type 1 (HSV-1) is not only an effective antitumor drug but also an excellent vector. Herein, RNAi of oncogenes Bcl-2 and Survivin was combined with oncolytic HSV-1 (ICP34.5-/ICP6-/ICP47-/CMV-GM-CSF) and a new vector HSV010-BS was constructed. Transfected cell viability assays and animal experiments revealed that the dual silencing of Bcl-2 and Survivin improved the antitumor effect of oncolytic HSV-1 in vitro and in vivo, while the antitumor effect was correlated with the phosphorylation levels of PKR of the tumor cells. The higher the phosphorylation levels of PKR of the tumor cells, the weaker the replication ability of oncolytic HSV-1, and the more powerful HSV010-BS was than its control vectors in inhibiting the growth of the tumor cells. The results provided direct supportive proofs for a new potential cancer therapy strategy. [ABSTRACT FROM AUTHOR]

Background:Chinese women tend to have small and dense breasts and ultrasound is a common method for breast cancer screening in China. However, its efficacy and cost comparing with mammography has not been evaluated in randomised trials.Methods:At 14 breast centres across China during 2008-2010, 13 339 high-risk women aged 30-65 years were randomised to be screened by mammography alone, ultrasound alone, or by both methods at enrolment and 1-year follow-up.Results:A total of 12 519 and 8692 women underwent the initial and second screenings, respectively. Among the 30 cancers (of which 15 were stage 0/I) detected, 5 (0.72/1000) were in the mammography group, 11 (1.51/1000) in the ultrasound group, and 14 (2.02/1000) in the combined group (P=0.12). In the combined group, ultrasound detected all the 14 cancers, whereas mammography detected 8, making ultrasound more sensitive (100 vs 57.1%, P=0.04) with a better diagnostic accuracy (0.999 vs 0.766, P=0.01). There was no difference between mammography and ultrasound in specificity (100 vs 99.9%, P=0.51) and positive predictive value (72.7 vs 70.0%; P=0.87). To detect one cancer, the costs of ultrasound, mammography, and combined modality were $7876, $45 253, and $21 599, respectively.Conclusions:Ultrasound is superior to mammography for breast cancer screening in high-risk Chinese women. [ABSTRACT FROM AUTHOR]

The mechanistic effects of intravenous glucose, insulin and potassium (GIK) in cardiac ischemia are not well understood. We conducted a genetic sub-study of the Immediate Myocardial Metabolic Enhancement During Initial Assessment and Treatment in Emergency care (IMMEDIATE) Trial to explore effects of common and rare glucose and insulin-related genetic loci on initial to 6-h and 6- to 12-h change in plasma glucose and potassium. We identified 27 NOTCH2/ADAM30 and 8 C2CD4B variants conferring a 40-57% increase in glucose during the first 6 h of infusion (P<5.96 × 10−6). Significant associations were also found for ABCB11 and SLC30A8 single-nucleotide polymorphisms (SNPs) and glucose responses, and an SEC61A2 SNP with a potassium response to GIK. These studies identify genetic factors that may impact the metabolic response to GIK, which could influence treatment benefits in the setting of acute coronary syndromes (ACS). [ABSTRACT FROM AUTHOR]

Background: Chinese women tend to have small and dense breasts and ultrasound is a common method for breast cancer screening in China. However, its efficacy and cost comparing with mammography has not been evaluated in randomised trials.Methods: At 14 breast centres across China during 2008-2010, 13 339 high-risk women aged 30-65 years were randomised to be screened by mammography alone, ultrasound alone, or by both methods at enrollment and 1-year follow-up.Results: A total of 12 519 and 8692 women underwent the initial and second screenings, respectively. Among the 30 cancers (of which 15 were stage 0/I) detected, 5 (0.72/1000) were in the mammography group, 11 (1.51/1000) in the ultrasound group, and 14 (2.02/1000) in the combined group (P=0.12). In the combined group, ultrasound detected all the 14 cancers, whereas mammography detected 8, making ultrasound more sensitive (100 vs 57.1%, P=0.04) with a better diagnostic accuracy (0.999 vs 0.766, P=0.01). There was no difference between mammography and ultrasound in specificity (100 vs 99.9%, P=0.51) and positive predictive value (72.7 vs 70.0%; P=0.87). To detect one cancer, the costs of ultrasound, mammography, and combined modality were $7876, $45 253, and $21 599, respectively.Conclusions: Ultrasound is superior to mammography for breast cancer screening in high-risk Chinese women. [ABSTRACT FROM AUTHOR]

Tb3+-doped Zn–Al (Zn–Al–Tb) hydrotalcites with tunable blue-green emission synthesized by co-precipitation. The compositions and properties of the samples were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and photoluminescence. XRD and FTIR results indicate that the samples were in a pure hydrotalcite-like phase. The fluorescence spectra indicate that the Zn–Al hydrotalcite exhibited blue fluorescence at 350–450 nm. Under an excitation wavelength of 231 nm, Zn–Al–Tb hydrotalcite exhibited the characteristic green emission of 5D0–7FJ of Tb3+, and the fluorescence lifetime of the sample was 0.8442 ms. At different excitation wavelengths, Zn–Al–Tb hydrotalcites can exhibit emission from green to blue wavelengths, which indicates that Zn–Al–Tb hydrotalcites are potential multicolor functional materials. [ABSTRACT FROM AUTHOR]

Deformation twinning was thought as impossible in ionic compounds with rock-salt structure due to the charge effect on {111} planes. Here we report the presence and formation mechanism of deformation {111} twins in the rock-salt manganese sulphide (MnS) inclusions embedded in a hot-rolled stainless steel. Based on the atomic-scale mapping under aberration-corrected scanning transmission electron microscopy, a dislocation-based mechanism involved two synchronized shear on adjacent atomic layers is proposed to describe the dislocation glide and consequently twinning formation. First-principles calculations of the energy barriers for twinning formation in MnS and comparing with that of PbS and MgO indicate the distinct dislocation glide scheme and deformation behaviors for the rock-salt compounds with different ionicities. This study may improve our understanding of the deformation mechanisms of rock-salt crystals and other ionic compounds. [ABSTRACT FROM AUTHOR]

Room temperature tensile testing was performed on a coarse-grained polycrystalline Ni (32 μm), a nanocrystalline Ni (23 nm) and two nanocrystalline Ni-Fe (16 nm) electrodeposits at two strain rates of 10 and 10/s. Strain localizations and local temperature increases were simultaneously recorded during tensile testing. For all materials, higher loads or higher strain rate generally resulted in higher peak temperature with the highest temperatures recorded in the fracture regions. The maximum temperature for the nanocrystalline materials was just over 80 °C, which is significantly below the reported temperatures for the onset of thermally activated grain growth. Therefore, the previously reported grain growth observed on similar materials after tensile deformation is likely not thermally activated but a stress-induced phenomenon. Despite the wide grain range from 16 nm to 32 μm, all samples exhibited similar strain localization behavior. Local strain variations initiated in the early stage of macroscopic uniform deformation, subsequent necking and fracture took place in the region of initial strain localization. While the coarse-grained polycrystalline Ni exhibited little strain rate sensitivity, gradually increased strain rate sensitivity was observed for the 23 nm Ni and the two 16 nm Ni-Fe samples, suggesting that both dislocation-mediated and grain-boundary-controlled mechanisms were operative in the deformation of the nanocrystalline Ni and Ni-Fe samples. [ABSTRACT FROM AUTHOR]

This article performs an exact analysis for a frictional triangular or cylindrical punch acting on the surface of magneto-electro-elastic materials. The punch moves relative to the surface of magneto-electro-elastic materials. Inside the contact area, the Coulomb friction law is applied. Eigenvalue distribution is analyzed, and then appropriate fundamental solutions are given. The stated problem is reduced to a system of singular integral equations of the second kind. The exact solution of the obtained singular integral equations makes it easy to get the explicit expressions of the surface physical quantities. Through plotting figures, the influences of the friction coefficient on contact behavior are shown and interesting results are observed. The in-plane stress, electric displacement and magnetic induction tend to be infinite near the leading edge of the frictional triangular punch, while having spikes at one edge of the frictional cylindrical punch, which may explain why surface damage occurs on the surface of magneto-electro-elastic materials. [ABSTRACT FROM AUTHOR]

Resistance to chemotherapeutic treatment, which is indirectly responsible for many cancer deaths, is normally associated with an aggressive phenotype including increased cell motility and acquisition of invasive properties. Here we describe how breast cancer cells overcome doxorubicin-induced senescence and become drug resistant by overexpression of the microRNA (miR)-106b∼25 cluster. Although all three miRs in the cluster contribute to the generation of doxorubicin resistance, miR-25 is the major contributor to this phenotype. All three miRs in this cluster target EP300, a transcriptional activator of E-cadherin, resulting in cells acquiring a phenotype characteristic of cells undergoing epithelial-to-mesenchymal transition (EMT), including an increase in both cell motility and invasion, as well as the ability to proliferate after treatment with doxorubicin. These findings provide a novel drug resistance/EMT regulatory pathway controlled by the miR-106b∼25 cluster by targeting a transcriptional activator of E-cadherin. [ABSTRACT FROM AUTHOR]

The bulk specific heat of fully dense nanocrystalline Ni-P electrodeposits with essentially constant P content (about 4 at%) and varying average grain sizes from 6.9 to 28.9 nm was investigated using modulated differential scanning calorimetry. In the lower temperature range from room temperature to 120 °C, at which the as-deposited sample microstructure was thermally stable, the bulk specific heat varied only within ~2 % despite the substantial variation of interface volume fractions from 0.11 to 0.39 for this series of samples. Moreover, the measured bulk specific heat values of the Ni-P samples were all located within the reported specific heat value range for conventional polycrystalline Ni. Evidently, the contribution due to grain size-related interface excess free volume is negligible and the bulk specific heat for the materials can be characterized as a structure-insensitive property. In the elevated temperature range from 150 °C to the Curie temperature of 357 °C, the magnetic contribution to the specific heat was significantly influenced by the chemical environment of P in the Ni-P samples. When P atoms were in the form of supersaturated solution in the nickel matrix, a complete suppression of the characteristic λ peak of the magnetic contribution in the specific heat curves was observed for all materials. The λ peak re-appeared in the specific heat curve after the Ni-P sample underwent a transformation to a two-phase microstructure consisting of Ni and NiP grains. It can be concluded that at a given P content, paramagnetic phosphorus atoms in the form of solutes are more effective in reducing the magnetic contributions to the specific heat than the form of paramagnetic NiP second-phase particles for the nanocrystalline Ni-P alloy. [ABSTRACT FROM AUTHOR]

Studies have reported inconsistent results concerning the association of cesarean section with offspring obesity. We performed a systematic review and meta-analysis to examine whether cesarean section increases the risk of later overweight and obesity. Pubmed, Embase and Web of Science were searched using different combinations of two groups of keywords: 'cesarean' and 'overweight/obesity'. Cohort or case-control studies that reported the association of cesarean section with childhood (3-8 years), adolescence (9-18 years) and/or adult (>19 years) overweight/obesity were eligible. Where possible, adjusted risk estimates were pooled using a random effects model; otherwise unadjusted estimates were pooled. Statistical heterogeneity was assessed with I2 statistics; the values of 25%, 50% and 75% were considered to indicate low, medium and high heterogeneity, respectively. We conducted a subgroup analysis to identify the sources of heterogeneity according to study quality defined on the basis of the Newcastle-Ottawa Scale. In total, two case-control and seven cohort studies were identified for the literature review and 15 separate risk estimates were included in the meta-analysis. The overall pooled odds ratio (OR) of overweight/obesity for offspring delivered by cesarean section compared with those born vaginally was 1.33 (95% confidence interval (CI) 1.19, 1.48; I2=63%); the OR was 1.32 (1.15, 1.51) for children, 1.24 (1.00, 1.54) for adolescents and 1.50 (1.02, 2.20) for adults. In subgroup analysis, the overall pooled OR was 1.18 (1.09, 1.27; I2=29%) for high-quality studies and 1.78 (1.43, 2.22; I2=24%) for medium-quality (P for interaction=0.0005); no low-quality studies were identified. The ORs for children, adolescents and adults all tended to be lower for high-quality studies compared with medium-quality studies. Our results indicated that cesarean section was moderately associated with offspring overweight and obesity. This finding has public health implications, given the increase in cesarean births in many countries. [ABSTRACT FROM AUTHOR]

The lasting high fuel cost has recently inspired resurgence in drag reduction research for vehicles, which calls for a thorough understanding of the vehicle wake. The simplified Ahmed vehicle model is characterized by controllable flow separation, thus especially suitable for this purpose. In spite of a considerable number of previous investigations, our knowledge of flow around this model remains incomplete. This work aims to revisit turbulent flow structure behind this model. Two rear slant angles, i.e., α = 25º and 35º, of the model were examined, representing two distinct flow regimes. The Reynolds number was 5.26 × 10 based on the model height ( H) and incident flow velocity. Using particle image velocimetry (PIV), flow was measured with and without a gap ( g/H = 0.174) between the vehicle underside and ground in three orthogonal planes, viz. the x- z, x- y and y- z planes, where x, y, and z are the coordinates along longitudinal, transverse, and spanwise directions, respectively. The flow at g/H = 0 serves as an important reference for the understanding of the highly complicated vehicle wake ( g/H ≠ 0). While reconfirming the well-documented major characteristics of the mean flow structure, both instantaneous and time-averaged PIV data unveil a number of important features of the flow structure, which have not been previously reported. As such, considerably modified flow structure models are proposed for both regimes. The time-averaged velocities, second moments of fluctuating velocities, and vorticity components are presented and discussed, along with their dependence on g/H in the two distinct flow regimes. [ABSTRACT FROM AUTHOR]

Malignant ascites is common in various types of cancers and is difficult to manage. Vascular endothelial growth factor (VEGF) has a pivotal role in malignant ascites. The matrix protein of vesicular stomatitis virus (VSVMP) has been shown to inhibit host gene expression and induce the apoptosis of cancer cells. The present study was designed to determine whether VSVMP suppresses the formation of ascites in ascites-producing peritoneal carcinomatosis. BALB/c female mice, 6-8 weeks old, bearing peritoneal tumors of H22 or MethA cells received an intraperitoneal administration of 50 μg VSVMP/250 μg liposome complexes, 50 μg empty plasmid/250 μg liposome complexes or 0.9% NaCl solution, respectively, every 2 days for 3 weeks. Administration of VSVMP resulted in a significant inhibition in ascites formation, improvement in health condition and prolonged survival of the treated mice. Decreased peritoneum osmolarity and reduced tumor vascularity coincided with dramatic reductions in the VEGF level in ascites fluid and plasma. Examination of floating tumor cells collected from the peritoneal wash revealed an apparently increased number of apoptotic cells and profound downregulation of VEGF mRNA in the VSVMP-treated mice. Our data indicate for the first time that in BALB/c mice bearing H22 or MethA cell peritoneal tumors, VSVMP may inhibit VEGF production and suppress angiogenesis, consequently abolishing ascites formation. [ABSTRACT FROM AUTHOR]

The effect of cylinder aspect ratio (≡ H/ d, where H is the cylinder height or length, and d is the cylinder diameter) on the drag of a wall-mounted finite-length circular cylinder in both subcritical and critical regimes is experimentally investigated. Two cases are considered: a smooth cylinder submerged in a turbulent boundary layer and a roughened cylinder immersed in a laminar uniform flow. In the former case, the Reynolds number Re (≡ U d/ ν, with U being the free-stream velocity and ν the fluid viscosity) was varied from 2.61 × 10 to 2.87 × 10, and two values of H/ d (2.65 and 5) were examined; in the latter case, Re = 1.24 × 10-1.73 × 10 and H/ d = 3, 5 and 7. In the subcritical regime, both the drag coefficient C and the Strouhal number St are smaller than their counterparts for a two-dimensional cylinder and reduce monotonously with decreasing H/ d. The presence of a turbulent boundary layer causes an early transition from the subcritical to critical regime and considerably enlarges the Re range of the critical regime. No laminar separation bubble occurs on the finite-length cylinder immersed in the turbulent boundary layer, and consequently, the discontinuity is not observed in the C- Re and St- Re curves. In the roughened cylinder case, the Re range of the critical regime grows gradually with decreasing H/ d, while the C crisis becomes less obvious. In both cases, H/ d has a negligible effect on the critical value of Re at which transition occurs from the subcritical to critical regime. [ABSTRACT FROM AUTHOR]

Experiments conducted under controlled conditions can be poor predictors of the field performance of rhizobial inoculants. In this study, five field experiments were conducted over 2 years to evaluate the symbiotic performance of 12 previously identified strains isolated from Australia and Myanmar soils that had potential to improve chickpea productivity through symbiotic N2 fixation. Strains collected from Australian soils had more than double the survival on seed and up to three times the nodulation at some experimental sites, compared with strains isolated from Myanmar soils. Generally, the newly isolated strains did not perform better than the current Australian commercial strain, Mesorhizobium ciceri CC1192. Although Myanmar strains had poor nodulation of chickpea plants (below nodule rating 1 in most cases) under Australian field conditions, the plant traits related to growth and symbiosis, such as shoot dry weight (SDW), yield and N fixation, were improved and sometimes equal to the plants inoculated with the Australian strains. Partial correlations showed that plants inoculated with Myanmar strains had greater associations with N fixation measurements (7 plant traits) than nodule number (1 trait), while a symbiotic effectiveness measure of the ratio between N fixation and nodule mass indicated that Myanmar strains are more than 75% more symbiotically efficient compared with the Australian strains. Better seed and soil survival of the Myanmar strains may increase plant nodulation and may lead to a highly effective inoculant strain. This study is one of the first to report increased symbiotic efficiency of N fixation of novel strains compared to a widely utilised commercial chickpea-nodulating strain, on a per nodule basis. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) were deposited on bare glass, Au (10 nm)/glass, and Au (50 nm)/glass substrates, and observed using a scanning electron microscope (SEM) operating at different accelerating voltages. Depending on the substrate and accelerating voltage, the CNTs exhibit different levels of contrast. On the poorly conductive glass and Au (10 nm)/glass substrates, electrons are supplied or dissipated through the networked CNTs. This generates a potential difference between the CNTs and the (insulating or poorly conductive) substrates. CNTs are visualized as a result of potential contrast. At a low accelerating voltage (1 kV), the substrate is of higher potential than that of the networked CNTs (the ground potential), and the CNTs exhibit bright contrast. At a high-accelerating voltage (5-10 kV), the potential of the substrate is lower than the networked CNTs, and the CNTs exhibit dark contrast. On the Au (50 nm)/glass conductive substrates, the electrons are supplied through both the Au film and the CNTs, and topographic morphology of CNTs is observed. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the early clinical outcome of reconstruction with modular hemipelvic prostheses after pelvic sarcoma resection.Methods: We retrospectively reviewed eight patients between 2004 and 2007 who had periacetabular resections and reconstruction with a modular hemipelvic prosthetic system for pelvic sarcoma with a mean follow-up of 27 (range,10~54) months. Oncology outcome was assessed with survival rate, local recurrence rate, International Society of Limb Salvage (ISOLS) score and complications. Two patients had types I and II (periacetabular and ilium) pelvic resections, three had types II and III (periacetabular and pubis) pelvic resections and three had type I , II and III (ilium, periacetabular and pubis) pelvic resections. Nobody received chemotherapy or radiotherapy.Results: Five patients were free of disease; three patients died of disease. The overall survival rate was 62.5%. None had local recurrence, and 37.5% had metastasis. The mean ISOLS score was 19.5. No one had deep infection or dislocation.Conclusions: Reconstruction with a modular hemipelvic prosthetic system after periacetabular resection is a promising method because of the acceptable complication rate and satisfactory functional outcome. [ABSTRACT FROM AUTHOR]

Epidemiological studies have evaluated the association between X-ray repair cross-complementing group 1 gene (XRCC1) Arg399Gln and Arg194Trp polymorphisms and risk of prostate cancer (PCa). However, the results from the published studies on the association between these two XRCC1 polymorphisms and PCa risk are conflicting. To derive a more precise estimation of association between the XRCC1 polymorphisms and risk of PCa, we performed a meta-analysis. A comprehensive search was conducted to identify all case-control studies of XRCC1 polymorphisms and PCa risk. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. Overall, we found that both Arg399Gln and Arg194Trp polymorphisms were not significantly associated with PCa risk. However, in stratified analysis by ethnicity, we found that the Arg399Gln polymorphism was significantly associated with PCa risk in Asian population (Gln/Gln vs Arg/Arg: OR=1.46, 95% CI: 1.05-2.03, P=0.03; Gln/Gln vs Arg/Gln+Arg/Arg: OR=1.48, 95% CI: 1.12-1.95, P=0.01). In this meta-analysis, we found that both Arg399Gln and Arg194Trp polymorphisms were not related to overall PCa risk. However, in subgroup analysis we found a suggestion that XRCC1 399Gln allele might be a low-penetrent risk factor for PCa only in Asian men. [ABSTRACT FROM AUTHOR]

1 M LiPF dissolved in oligo(ethylene glycol) dimethyl ether with a molecular weight 500 g mol was investigated as a new electrolyte (OEGDME500, 1 M LiPF) for metal deposition and battery applications. At 25 °C a conductivity of 0.48 × 10 S cm was obtained and at 85 °C, 3.78 × 10 S cm. The apparent activation barrier for ionic transport was evaluated to be 30.7 kJ mol. OEGDME500, 1 M LiPF allows operating temperature above 100 °C with very attractive conductivity. The electrolyte shows excellent performance at negative and positive potentials. With this investigation, we report experimental results obtained with aluminum electrodes using this electrolyte. At low current densities lithium ion reduction and re-oxidation can be achieved on aluminum electrodes at potentials about 280 mV more positive than on lithium electrodes. In situ X-ray diffraction measurements collected during electrochemical lithium deposition on aluminum electrodes show that the shift to positive potentials is due to the negative Gibbs free energy change of the Li-Al alloy formation reaction. [ABSTRACT FROM AUTHOR]

1 M LiPF dissolved in oligo(ethylene glycol) dimethyl ether with a molecular weight, 500 g mol (OEGDME500, 1 M LiPF), was investigated as an electrolyte in experimental Al-Li/LiFePO cells. More than 60 cycles were achieved using this electrolyte in a Li-ion cell with an Al-Li alloy as an anode sandwiched between two LiFePO electrodes (cathodes). Charging efficiencies of 96-100% and energy efficiencies of 86-89% were maintained during 60 cycles at low current densities. A theoretical investigation revealed that the specific energy can be increased up to 15% if conventional LiC anodes are replaced by Al-Li alloy electrodes. The specific energy and the energy density were calculated as a function of the active mass per electrode surface (charge density). The results reveal that for a charge density of 4 mAh cm about 160 mWh g can be reached with Al-Li/LiFePO batteries. Power limiting diffusion processes are discussed, and the power capability of Al-Li/LiFePO cells was experimentally evaluated using conventional electrolytes. [ABSTRACT FROM AUTHOR]

Cancer-causing mutations disrupt coordinated, precise programs of gene expression that govern cell growth and differentiation. Microarray-based gene-expression profiling (GEP) is a powerful tool to globally analyze these changes to study cancer biology and clinical behavior. Despite overwhelming genomic chaos in multiple myeloma (MM), expression patterns within tumor samples are remarkably stable and reproducible. Unique expression patterns associated with recurrent chromosomal translocations and ploidy changes defined molecular classes with differing clinical features and outcomes. Combined molecular techniques also dissected two distinct, reproducible forms of hyperdiploid disease and have molecularly defined MM with high risk for poor clinical outcome. GEP is now used to risk-stratify patients with newly diagnosed MM. Groups with high-risk features are evident in all GEP-defined MM classes, and GEP studies of serial samples showed that risk increases over time, with relapsed disease showing dramatic GEP shifts toward a signature of poor outcomes. This suggests a common mechanism of disease evolution and potentially reflects preferential expansion of therapy-resistant cells. Correlating GEP-defined disease class and risk with outcomes of therapeutic regimens reveals class-specific benefits for individual agents, as well as mechanistic insights into drug sensitivity and resistance. Here, we review modern genomics contributions to understanding MM pathogenesis, prognosis, and therapy. [ABSTRACT FROM AUTHOR]

The effect of Nb content on the microstructure and mechanical properties of Zr-based bulk metallic glass (BMG) were investigated. The addition of Nb led to the formation of the Zr-based metallic glass composites with a ductile dentritic phase by in situ precipitation. The presence of the in situ precipitated phase enhanced significantly the plasticity of the composite under uniaxial compressive test. The interactions between the precipitated phase and the shear band affect the deformation mechanism and fracture mode of the BMG by enhancing the affecting level of the normal stress on the shear surface, and the constant α in the Mohr–Coulomb criterion can reflect the extent of the interactions among particles and the amorphous matrix. [ABSTRACT FROM AUTHOR]

The role of RNA-binding proteins in cancer biology is recognized increasingly. The nucleocytoplasmic shuttling and AU-rich RNA-binding protein HuR stabilizes several cancer-related target mRNAs. The proto-oncogene c-fms, whose 3′untranslated region (3′UTR) is not AU-rich, is associated with poor prognosis in breast cancer. Using a large breast-cancer tissue array (N=670), we found nuclear HuR expression to be associated with nodal metastasis and independently with poor survival (P=0.03, RR 1.45), as well as to be co-expressed with c-fms in the breast tumors (P=0.0007). We described c-fms mRNA as a direct target of HuR in vivo, and that HuR bound specifically to a 69-nt region containing ‘CUU’ motifs in 3′UTR c-fms RNA. Overexpressing or silencing HuR significantly up- or down-regulated c-fms RNA expression, respectively. We also found that known glucocorticoid stimulation of c-fms RNA and protein is largely dependent on the presence of HuR. HuR, by binding to the 69-nt wild type, but not mutant, c-fms sequence can regulate reporter gene expression post-transcriptionally. We are the first to describe that HuR can regulate gene expression by binding non-AU-rich sequences in 3′UTR c-fms RNA. Collectively, our findings suggest that HuR plays a supportive role for c-fms in breast cancer progression by binding a 69-nt element in its 3′UTR, thus regulating its expression.Oncogene (2009) 28, 1176–1186; doi:10.1038/onc.2008.469; published online 19 January 2009 [ABSTRACT FROM AUTHOR]

The cellular mechanisms regulating intestinal differentiation are poorly understood. Sodium butyrate (NaBT), a short-chain fatty acid, increases p27Kip1 expression and induces cell cycle arrest associated with intestinal cell differentiation. Here, we show that treatment of intestinal-derived cells with NaBT induced G0/G1 arrest and intestinal alkaline phosphatase, a marker of differentiation, activity and mRNA expression; this induction was attenuated by inhibition of glycogen synthase kinase-3 (GSK-3). Moreover, treatment with NaBT increased the nuclear, but not the cytosolic, expression and activity of GSK-3β. NaBT decreased cyclin-dependent kinase CDK2 activity and induced p27Kip1 expression; inhibition of GSK-3 rescued NaBT-inhibited CDK2 activity and blocked NaBT-induced p27Kip1 expression in the nucleus but not in the cytoplasm. In addition, we demonstrate that NaBT decreased the expression of S-phase kinase-associated protein 2 (Skp2), and this decrease was attenuated by GSK-3 inhibition. Furthermore, NaBT increased p27Kip1 binding to CDK2, which was completely abolished by GSK-3 inhibition. Overexpression of an active form of GSK-3β reduced Skp2 expression, increased p27Kip1 in the nucleus and increased p27Kip1 binding to CDK2. Our results suggest that GSK-3 not only regulates nuclear p27Kip1 expression through the downregulation of nuclear Skp2 expression but also functions to regulate p27Kip1 assembly with CDK2, thereby playing a critical role in the G0/G1 arrest associated with intestinal cell differentiation.Cell Death and Differentiation (2008) 15, 908–919; doi:10.1038/cdd.2008.2; published online 8 February 2008 [ABSTRACT FROM AUTHOR]

To understand the genetic gains of grain yield in the Southern China Winter Wheat Region (SCWWR), two yield potential trials, i.e., YPT 1 including 11 leading cultivars from the Middle and Low Yangtze Valley (Zone III) and YPT 2 including 15 leading cultivars from the Southwestern China Region (Zone IV) from 1949 to 2000, were conduced during the 2001–2003 cropping seasons. A completely randomized block design of three replicates was employed with controlled field environments. Molecular markers were used to detect the presence of dwarfing genes and the 1B/1R translocation. Results showed that average annual genetic gain was 0.31% ( P < 0.05) or 13.96 kg/ha/year and 0.74% ( P < 0.01) or 40.80 kg/ha/year in Zones III and IV, respectively. In YPT 1, changes of all other traits were not significant, but plant height was significantly reduced. In YPT 2, the genetic improvement of grain yield was primarily attributed to the increased thousand kernel weight (TKW) (0.65%, P < 0.01) and kernel weight/spike (0.87%, P < 0.01), reduced plant height and increased harvest index (HI). The dwarfing gene Rht 8 was most frequently present (46.1%), Rht-B1b was observed in three genotypes in Zone III, and Rht-D1b was present in only one genotype in Zone IV. The 1B/1R translocation was present in four genotypes. Utilization of Italian germplasm and development of landmark cultivar Fan 7 were the key factors for grain yield improvement in SCWWR. The future challenge of wheat breeding in this region is to continue improving grain yield and disease resistance, and to develop cultivars suitable for the reduced tillage of wheat/rice double cropping. Utilization of Mexican germplasm could provide opportunities for future yield improvement. [ABSTRACT FROM AUTHOR]

The prometastatic oncogene synuclein-γ (SNCG) is not expressed in normal lung tissues, but it is highly expressed in lung tumors. Here, we show that cigarette smoke extract (CSE) has strong inducing effects on SNCG gene expression in A549 lung cancer cells through demethylation of SNCG CpG island. CSE treatment also augments the invasive capacity of A549 cells in an SNCG-dependent manner. To elucidate the mechanisms underlying the demethylating effects of CSE, we examined expression levels of DNA methyltransferases (DNMTs), 1, 3A and 3B in CSE-treated cells. We show that the mRNA expression of DNMT3B is specifically downregulated by CSE with a kinetics concurrent to SNCG reexpression. Utilizing siRNA to knockdown DNMT3B expression, we show that inhibition of DNMT3B directly increases SNCG mRNA expression. We further show that exogenous overexpression of DNMT3B in an SNCG-positive lung cancer cell line H292 suppresses SNCG mRNA and protein expression and induces de novo methylation of SNCG CpG island, whereas overexpression of DNMT1 or DNMT3A has no effects. Taken together, these new findings demonstrate that tobacco exposure induces the abnormal expression of SNCG in lung cancer cells through downregulation of DNMT3B. This work sheds light on the molecular understanding of demethylation of this oncogene during cancer progression.Oncogene (2007) 26, 5900–5910. doi:10.1038/sj.onc.1210400; published online 19 March 2007 [ABSTRACT FROM AUTHOR]

HPV16 E6 interacts with and degrades tumour suppressor protein TSC2 leading to the phosphorylation of p70 S6 kinase. We studied the association of S6 kinase phosphorylation and HPV16 infection in cervical cancer and esophageal cancer. Immunohistochemistry was used to assess phosphorylated S6 kinase (Thr 389) and phosphorylated S6 (Ser235/236) in 140 cervical cancer and 161 esophageal cancer specimens. Immunohistochemical staining for pS6 kinase and pS6 was significantly more frequent in the HPV16-infected cervical cancer specimens than the HPV16-negative specimens. In contrast, the expression of S6 kinase was similar in both HPV16-positive and -negative samples. The phosphorylation of Akt, the key regulator of S6 kinase, was also detected. Our analysis showed that Akt phosphorylation was unaffected by HPV16 infection. These results together with our previous study suggest that HPV16 modifies S6 kinase activation via mechanism, which activates S6 kinase downstream of Akt function.British Journal of Cancer (2007) 97, 218–222. doi:10.1038/sj.bjc.6603838 www.bjcancer.com Published online 10 July 2007 [ABSTRACT FROM AUTHOR]

Weibull modulus of bending strength of nanolayer-grained ceramic Ti3SiC2 was estimated with over 50 specimens, using the least square method, the moment method and the maximum likelihood technique, respectively. The result demonstrated that the m-value of this layered ceramic ranged from 25 to 29, which is much higher than that of traditional brittle ceramics. The reason of high Weibull modulus was due to high damage tolerance of this material. Under stress, delamination and kinking of grains and shear slipping at interfaces give this material high capacity of local energy dissipation and easy local stress relaxation, leading to the excellent damage tolerance of Ti3SiC2. The effect of amounts of specimens on the reliability of the estimated m-values was also investigated. It was confirmed that the stability of the estimated m-value increased with increasing numbers of specimens. The parameter obtained using the maximum likelihood technique showed the highest reliability than other methods. The ranges of failure probability were determined using the Weibull estimates calculated from the maximum likelihood technique. [ABSTRACT FROM AUTHOR]

Space grown BSO crystal doped with Ce was characterized by means of X-ray fluorescence spectra, X-ray topography, dislocation density etc. Influence of microgravity on Ce-doped BSO crystal defect was studied by comparing space grown BSO crystal with ground grown one. These results show that compositional homogeneity and structural perfection of crystal can be improved under microgravity conditions. [ABSTRACT FROM AUTHOR]

Aurora-A/STK15/BTAK, which encodes a centrosome-associated kinase, is amplified and overexpressed in multiple types of human tumors, including breast cancer. However, the causal relationship between overexpression of Aurora-A and tumorigenesis has not been fully established due to contradictory data obtained from different experimental systems. To investigate this, we generated a mouse strain that carries an MMTV-Aurora-A transgene. We showed that all the MMTV-Aurora-A mice displayed enhanced branch morphogenesis in the mammary gland and about 40% developed mammary tumors at 20 months of age. The tumor incidence was significantly increased in a p53+/− mutation background with about 70% MMTV-Aurora-A;p53+/− animals developed tumors at 18 months of age. Of note, overexpression of Aurora-A led to genetic instability, characterized by centrosome amplification, chromosome tetraploidization and premature sister chromatid segregation, at stages prior to tumor formation. Most notably, the severe chromosomal abnormality did not cause cell death owing to the activation of AKT pathway, including elevated levels of phosphorylated AKT and mammalian target of rapamycin, and nuclear accumulation of cyclin D1, which enabled continuous proliferation of the tetraploid cells. These data establish Aurora-A as an oncogene that causes malignant transformation through inducing genetic instability and activating oncogenic pathways such as AKT and its downstream signaling.Oncogene (2006) 25, 7148–7158. doi:10.1038/sj.onc.1209707; published online 22 May 2006 [ABSTRACT FROM AUTHOR]

By heating the admixture of a commercial liquid electrolyte (LB302, 1 M solution of LiPF6 in 1:1 EC/DEC), methyl methacrylate (MMA) and benzoyl peroxide (BPO, initiator), a poly(methyl methacrylate) (PMMA) based gel-polymer electrolyte (GPE) was obtained. AC impedance spectroscopy and cyclic voltammetry were used to evaluate its ionic conductivity and electrochemical stability window. Rechargeable cells LiNi0.8Co0.2O2/Li and LiNi0.8Co0.2O2/graphite with this MMA based GPE were also fabricated via the in-situ thermal polymerization process. This GPE exhibits a high ionic conductivity (over 10−3S cm−1) at room temperature. It is stable in the voltage range between 0 and 4.2 V (vs. Li+/Li). A phenomenon of large initial cell impedance (LICI) was observed for the LiNi0.8Co0.2O2/Li cells but not in LiNi0.8Co0.2O2/graphite cells. After the first several cycles, the cell impedance decreases substantially and reversible charge–discharge capacity can be obtained. This in-situ polymerization method provides a way to produce GPE cells. [ABSTRACT FROM AUTHOR]

Ahi-1 (Abelson helper integration site 1) is a novel gene frequently activated by provirus insertional mutagenesis in murine leukemias and lymphomas. Its involvement in human leukemogenesis is demonstrated by gross perturbations in its expression in human leukemia cells, particularly in cutaneous T-cell lymphoma cell lines where increases in AHI-1 transcripts of 40-fold are seen. To test directly whether deregulated expression of AHI-1 contributes to their transformed properties, knockdown of AHI-1 expression in Hut78 cells, a cell line derived from a patient with Sezary syndrome (SS), was performed using retroviral-mediated RNA interference. Retroviral-mediated suppression specifically inhibited expression of AHI-1 and its isoforms in transduced cells by 80% and also reduced autocrine production of interleukin (IL)-2, IL-4 and tumor necrosis factor-alpha (TNFα) by up to 85%. It further significantly reduced their growth factor independence in vitro and the ability to produce tumors in immunodeficient mice. Interestingly, aberrant expression of AHI-1, particularly truncated isoforms, was present in CD4+CD7− Sezary cells from some patients with SS. Elevated expression of IL-2 and TNFα was also found in these cells. These findings provide strong evidence of the oncogenic activity of AHI-1 in human leukemogenesis and demonstrate that its deregulation may contribute to the development of SS.Leukemia (2006) 20, 1593–1601. doi:10.1038/sj.leu.2404321; published online 13 July 2006 [ABSTRACT FROM AUTHOR]

The parasitoid Cotesia glomerata usually produces female-biased sex ratios in the field, which are presumably caused by inbreeding and local mate competition (LMC); yet, sibling mating increases the production of males, leading to the male-biased sex ratio of broods in the laboratory. Previous studies have suggested that the sex allocation strategy of C. glomerata is based on both partial LMC in males and inbreeding avoidance in females. The current study investigated the presence of single-locus complementary sex determination (sl-CSD) as a sex-determining mechanism in this species through inbreeding experiment, cytological examination and microsatellite analysis. Cytological examination detected diploid males in nine of 17 single pairs of sibling mating, thus in agreement with the proportion of matched matings predicted by the sl-CSD model. Sex ratio shifts in these matched sibling matings were consistent with the sl-CSD model with less viable diploid males. The haploid males have a single set of maternal chromosomes (n=10), whereas diploid males possess a double set of chromosomes (2n=20). Microsatellite analyses confirmed that diploid males produced from the matched matings inherited segregating genetic materials from both parents. Thus, this study provides the first solid evidence for the presence of sl-CSD as a sex-determining mechanism in the braconid genus Cotesia.Heredity (2006) 96, 487–492. doi:10.1038/sj.hdy.6800829; published online 19 April 2006 [ABSTRACT FROM AUTHOR]

Interspecific and intergeneric hybridizations were carried out to evaluate the genomic relationships among species of Hystrix Moench and to study the relationships between Hystrix species and Psathyrostachys huashanica Keng (2n=2x=14, Ns h ). Meiotic pairing in hybrids of Hystrix duthiei ssp. duthiei × P. huashanica (2n=3x=21), Hystrix duthiei ssp. longearistata × P. huashanica (2n=3x=21) and H. patula × P. huashanica (2n=3x=21) averaged 5.18, 5.11 and 0.29 bivalents per cell, while H. patula × H. duthiei ssp. longearistata (2n=4x=28) averaged 25.36 univalents and 1.32 bivalents per cell, respectively. The results indicate that (i) H. duthiei ssp. duthiei and H. duthiei ssp. longearistata have one set of Ns genome from Psathyrostachys; (ii) H. patula has no Ns genome; (iii) genomes of H. duthiei ssp. duthiei and H. duthiei ssp. longearistata are non-homologous to those of H. patula. The genomic relationships between H. patula and other Hystrix species are also discussed. [ABSTRACT FROM AUTHOR]

Changes in cell morphology are linked to many cellular events including cytokinesis, differentiation, migration and apoptosis. We recently showed that BNIP-Sα induced cell rounding that leads to apoptosis via its BNIP-2 and Cdc42GAP Homology (BCH) domain, but the underlying mechanism has not been determined. Here, we have identified a unique region (amino acid 133–177) of the BNIP-Sα BCH domain that targets RhoA, but not Cdc42 or Rac1 and only the dominant-negative form of RhoA could prevent the resultant cell rounding and apoptotic effect. The RhoA-binding region consists of two parts; one region (residues 133–147) that shows some homology to part of the RhoA switch I region and an adjacent sequence (residues 148–177) that resembles the REM class I RhoA-binding motif. The sequence 133–147 is also necessary for its heterophilic interaction with the BCH domain of the Rho GTPase-activating protein, p50RhoGAP/Cdc42GAP. These overlapping motifs allow tripartite competition such that overexpression of BNIP-Sα could reduce p50RhoGAP binding to RhoA and restore RhoA activation. Furthermore, BNIP-Sα mutants lacking the RhoA-binding motif completely failed to induce cell rounding and apoptosis. Therefore, via unique binding motifs within its BCH domain, BNIP-Sα could interact and activate RhoA while preventing its inhibition by p50RhoGAP. This concerted mechanism could allow effective propagation of the RhoA pathway for cell rounding and apoptosis.Oncogene (2006) 25, 2393–2408. doi:10.1038/sj.onc.1209274; published online 5 December 2005 [ABSTRACT FROM AUTHOR]

Glycogen-synthase kinase-3 (GSK-3) and extracellular signal-regulated kinase (ERK) are critical downstream signaling proteins for the PI3-kinase/Akt and Ras/Raf/MEK-1 pathway, respectively, and regulate diverse cellular processes including embryonic development, cell differentiation and apoptosis. Here, we show that inhibition of GSK-3 using GSK-3 inhibitors or RNA interference (RNAi) significantly induced the phosphorylation of ERK1/2 in human colon cancer cell lines HT29 and Caco-2. Pretreatment with the PKCδ-selective inhibitor rottlerin or transfection with PKCδ siRNA attenuated the phosphorylation of ERK1/2 induced by the GSK-3 inhibitor SB-216763 and, furthermore, treatment with SB-216763 or transfection with GSK-3α and GSK-3β siRNA increased PKCδ activity, thus identifying a role for PKCδ in the induction of ERK1/2 phosphorylation by GSK-3 inhibition. Treatment with SB-216763 increased expression of cyclooxygenase-2 (COX-2) and IL-8, which are downstream targets of ERK1/2 activation; this induction was abolished by MEK/ERK inhibition, suggesting GSK-3 inhibition induced COX-2 and IL-8 through ERK1/2 activation. The transcriptional induction of COX-2 and IL-8 by GSK-3 inhibition was further demonstrated by the increased COX-2 and IL-8 promoter activity after SB-216763 treatment or transfection with GSK-3α or GSK-3β siRNA. Importantly, our findings identify GSK-3, acting through PKCδ, as a negative regulator of ERK1/2, thus revealing a novel crosstalk mechanism between these critical signaling pathways. [ABSTRACT FROM AUTHOR]