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We numerically study the thermoelectric transport properties in bilayer phosphorene in the presence of bias voltage under a strong magnetic field. When a bias voltage is applied and the bulk energy gap is closed, it is found that thermoelectric coefficients has similar properties to those of a semimetal. Around the central Landau Level (LL), the transverse thermoelectric conductivity displays a series of peaks, but the longitudinal thermoelectric conductivity oscillates and changes sign. The Nernst signal has a peak at central LL and changes sign near other LLs, while the thermopower has an opposite behavior. Both the thermoelectric conductivities and Nernst signal exhibit remarkable anisotropy, but thermopower exhibits isotropy.

The RASopathies are a group of syndromes that have in common germline mutations in genes that encode components of the RAS/mitogen-activated protein kinase (MAPK) pathway and have been a focus of study to understand the role of this pathway in development and disease. These syndromes include Noonan syndrome (NS), NS with multiple lentigines (NSML), neu-rofibromatosis type 1 (NF1), Costello syndrome (CS), cardio-facio-cutaneous (CFC) syndrome, neurofibromatosis type 1-like syndrome (NFLS) and capillary malformation-arteriovenous malformation syndrome (CM-AVM). These disorders affect multiple systems, including the craniofacial complex. Although the crani-ofacial features have been well described and can aid in clinical diagnosis, the dental phenotypes have not been analysed in detail for each of the RASopathies. In this review, we summarize the clinical features of the RASopathies, highlighting the reported craniofacial and dental findings.RAS信号通路相关综合征是由编码RAS-丝裂原激活蛋白激酶（RAS/mitogen-activated protein kinase，RAS/MAPK）信号通路的基因组突变而引起的一组综合征的统称。这些综合征包括努南综合征（Noonan syndrome，NS）、NS伴多发性雀斑（NS with multiple lentigines，NSML）、1型神经纤维瘤病（neurofibromatosis type 1，NF1）、科斯特罗综合征（Csotello syndrome，CS）、心-面-皮肤综合征（cardio-facio-cutaneous syndrome，CFC）、类1型神经纤维瘤病（NF1-like syndrome，NFLS）、毛细血管畸形-动静脉畸形综合征（capillary malformation-arteriovenous malformation syndrome，CM-AVM）。RAS信号通路相关综合征以颅颌面畸形和全身多系统畸形、功能障碍为特征。本文总结RAS信号通路相关综合征的颅颌面、口腔病变特征，以期了解RAS信号在颅颌面发育中的作用，为临床提供参考。.

The transcription factor Otx1 is specifically expressed in layer V pyramidal cells (L5PCs) in the cerebral cortex. Otx1 null mutant mice have a defect in the developmental axon pruning of L5PCs and show epileptic seizures. However, the role of Otx1 in electrophysiology, morphology and synaptology of the cortical neurons has not been fully investigated. This study examines the influences of Otx1 on neuronal properties of L5PCs by loss- and gain-of-function approaches. Mice with an Otx1-null mutation had decreased structural measurements of basal dendrites in L5PCs. In contrast, the size of basal dendrites was increased in the Otx1-over-expressed pyramidal cells (PCs) in L2/3 where the gene normally does not express. PCs showed burst and non-burst firing patterns of action potentials. The proportion of burst firing neurons was reduced in the Otx1 mutant but increased in the neurons over-expressing Otx1. Although the burst firing population decreased, the proportion of those bursting neurons with a low threshold increased in the Otx1 mutant mice. Moreover, excitatory facilitating synaptic connections formed between L5PCs were predominant in the Otx1 mutant mice, which greatly contrasted with the predominant depressing synaptic connections in the controls. Taken together, it suggests an enhanced activity of neuronal network in the cortex of Otx1 mutant mice. These data indicate that the Otx1 expression is essential for the normal development of dendritic morphology, intrinsic electrophysiology and synaptic dynamics of L5PCs. This study provides new insights into molecular mechanisms underlying the spatial and temporal regulation of neuronal and synaptic properties of L5PCs, and improves our understanding on the generation of epileptic seizures.

The non-destructive inspection method of scale on the inner wall of the ferritic steel and austenitic steel of high temperature boiler tube and the application effect were introduced in our work. The risk of scale exfoliation on the inner wall was also assessed. The risk of tube burst caused by scale exfoliation and accumulation, was reduced greatly, or even avoided by means of the change or treatment of high-risk tube confirmed by non-destructive inspection method.

In order to study the growth of diamond films over a large area in a traditional hot-filament chemical vapour deposition (HFCVD) reactor, two-dimensional mathematical models were first developed to investigate the temperature fields of the reactor walls, which made significant contributions to thermal round-flow of the reactant gases under different energy transfer systems. The set of partial differential equations involved in the thermal conduction system was solved with different boundary conditions by the finite control volume method. Numerical simulations showed that the temperature space distributions were heterogeneous when thermal radiation was assumed to be the only mechanism in heat transfer from the filaments to the reactor walls. However, taking into account the effects of thermal conduction under adiabatic and different isothermal temperature boundary conditions, the temperature uniformities improved greatly. In addition, thermal convection did not affect the temperature distributions but only increased the total temperature of the reactor wall. These results not only give insight into the dominant reasons resulting in low nucleation density and low growth rate of diamond films, but also provide a basis for the design of industrial HFCVD reactors to obtain high-quality diamond films over a large area.

This study focuses on the preparation of thermoplastic polyurethane (TPU) nanocomposite using Vietnamese montmorillonite (MMT) as the reinforced phase. The MMT was previously modified by intercalating polyethylene oxide (PEO) and polyvinyl alcohol (PVA) molecules between the clay layers. X-ray diffraction (XRD) results of organoclays revealed that galleries of MMT were increased to 18.2 Å and 27 Å after their intercalation with PEO and PVA, respectively. Thermoplastic polyurethane (TPU) nanocomposites composed of 1, 3, 5, and 7%wt organoclays were synthesized. The result of XRD and transmission electron microscopic (TEM) analyses implied that the PEO modified MMT was well dispersed, at 3%wt, in polyurethane matrix. Fourier Transform Infrared Spectroscopic (FTIR) has confirmed this result by showing the hydrogenous interaction between the urethane linkage and OH group on the surface of silicate layer. Thermogravimetric (TG) showed that the organoclay samples also presented improved thermal stabilities. In addition, the effects of the organoclays on mechanical performance and water absorption of the PU nanocomposite were also investigated.

This paper presents an investigation into the sulfate resistance of Portland cements and blended cements. Four Portland cements of different characteristics and blended cements containing fly ash, ground granulated blast furnace slag and silica fume were used in this work. The performances of binders were evaluated in sulfate solutions maintained at different pH levels ranging from 3 to 12 using expansion of mortar prisms (ASTM C 1012) and strength development of mortar cubes. The results indicate that sulfate resistance of cementitious materials is dependent on its composition and on the pH of the environment. Portland cement with low C3A and low C3S performed well in all sulfate solutions. Blended cements containing silica fume and fly ash (particularly at 40% replacement) showed a more superior performance than any of the Portland cements used. For slag blended cement, this can be achieved when the replacement percentage is higher than 60%. © 1997 Elsevier Science Ltd.

Resume La rupture spontanee de l'œsophage est une pathologie rare mais grave qui survient en general chez des patients ethyliques apres un effort de vomissement. Son pronostic depend de la precocite du diagnostic et du traitement. Suspecte cliniquement par l'association vomissement, douleur thoracique et emphyseme souscutane cervical, le diagnostic n'est pas toujours assure par les examens complementaires tels que la radiographie pulmonaire ou le transit œsophagien aux produits hydrosolubles. L'examen tomodensitometrique thoracique est classiquement indique en cas de tableau clinique evocateur avec transit œsophagien negatif ou en cas de ruptures œsophagiennes vues tardivement. Cet examen, couple au transit œsophagien a permis un diagnostic precoce de certitude et un bilan lesionnel precis chez 3 patients. Un traitement chirurgical a ete realise chez les 3 malades qui ont tous evolue favorablement. La tomodensitometrie thoracique associee au transit œsophagien aux produits hydrosolubles peut etre proposee comme examen de premiere intention dans les perforations spontanees de l'œsophage.

Influence of binder type on anodic dissolution of steel embedded in cement pastes with and without chloride is investigated by examination of anodic polarization curves. The results indicate that the formation of passive layer on steel embedded in cement paste is dependent on the type of binder used. In situation of chloride ion present in the mixing water, passive range is still observed at a concentration of 0.08 M NaCl. In the case of penetrating chloride, passive range of steel is either severely limited or not observed after 6 months of immersion in water with 0.02 M NaCl.

Dynamic polarization techniques were used to estimate the corrosion rates of steel embedded in cement paste made with different binder systems. A corrosion model is proposed. The corrosion rates were determined by employing the Evans diagrams constructed from cathodic polarization curve of steel embedded in chloride free cement paste and anodic polarization curve of steel embedded in cement pastes containing chloride. Within the limitations of the adopted experimental conditions and sample configuration, the preliminary results indicate that corrosion rates of steel embedded in blended cement pastes generally fall within the range shown by steel embedded in portland cement pastes.

A corrosion cell based on constant impressed voltage of 400 mV was developed to study corrosion rate of steel in concrete of different strength levels and in concrete with different silica fume contents. The results indicate that corrosion rate of steel embedded in saturated concrete can be reduced by increasing concrete strength, particularly in chloride contaminated environment. The use of 10 percent silica fume as cement replacement material in making 70 MPa concrete can have beneficial effect in terms of reduced corrosion rate. Adverse effect may results from using silica fume at higher replacement level of 20 percent.

Potentiodynamic Anodic Polarization techniques were used to investigate the corrosion characteristics of steel in solutions. The solutions were prepared by mixing different cements at a water-binder ratio of 2.0 and extraction after 3 and 7 days. Cements used in this investigation included an OPC with low C3A content, an OPC with high C3A content, a Slag Cement and a Fly Ash Cement. Results indicate that in the absence of chloride ions, the corrosion characteristics of steel in these solutions are very similar to those of steel in lime-saturated water. Despite differences in the rest potentials found in solutions made with the range of binder materials, steel passivation could be observed in all solutions. Passivation imparted to the steel by binder solutions was found to vary in the presence of increasing levels of chloride. A threshold chloride ion concentration for depassivation was established for each binder solution tested. Solutions made from the High C3A Cement and the Slag Cement displayed the best steel passivation characteristics, white the Low C3A Cement solution rated worst.

The association between teeth loss and temporomandibular disorders (TMD) is still inconclusive. A kind of secondary changes of the occlusion after teeth lose called the tightly locked occlusion (TLO), defined as the occluding contact that delivers angled occlusal force on the drifted neighbour and/or the tipped antagonists of the lost posterior teeth, was hypothesized to be association with TMD. The study aimed at investigating the association between the TLO and TMD. A total of 113 posterior-teeth losing patients, 64 with TMD symptoms (group of TMD) and 49 without (group of TMD-Free) were included. Study casts and joint radiographs were made to diagnose the TLO and joint morphological changes. The simultaneous contribution of the potential variables of gender, age, tooth losing number, the TLO, joint symmetry and signs of osteoarthrosis shown on radiographs were tested through binary logistic regression analysis. In women, the TLO entered into logistic model, and had an effect on the incidence of TMD (P = 0.008). The odds ratio of with-TLO versus without-TLO is 2.6 (95% CI: 1.2, 5.8) after controlling for the effect of gender. Age, tooth lose number, joint asymmetry or osseous changes had no effect on the incidence of TMD. The tightly locked occlusion is associated with some signs and symptoms of TMD. Randomized controlled trials will be needed in further studies to test the hypothesis that treatment of a TLO, as defined in the present study, will have a beneficial effect on the signs and symptoms of TMD.

The long-term performance of concrete slabs in alumina refineries has been found to be mostly unsatisfactory. The effect of exposure of concrete to sodium hydroxide of various concentrations has been reported. Failure of slabs accidentally exposed to hot caustic has been observed to be associated with cracking, crystallization of salts in the crack and seepage of caustic into subgrade, resulting in its expansion and uplift of the slabs. This deterioration mechanism of concrete in caustic are, however, not well understood. This paper presents findings into the interaction between a range of supplementary cementitious materials, such as blast furnace slag and silica fume, and sodium hydroxide solutions. The influence of the type of cementitious material, water-to-cementitious material ratio, concentration and temperature of sodium hydroxide on their interaction was investigated by examining the change in length of unrestrained mortar and concrete prisms exposed to sodium hydroxide solutions. The likely effect of the deterioration mechanism on the performance of restrained structural components, such as industrial slabs, is also examined by monitoring model slabs exposed to sodium hydroxide. The choice of cementitious material and its implications on the caustic resistance of concrete slabs subject to sodium hydroxide attack are presented.

Tamoxifen, a synthetic antiestrogen, is known for its antitumoral action in vivo; however, it is well accepted that many tamoxifen effects are elicited via estrogen receptor-independent routes. Previously, we reported that tamoxifen induces PKC translocation in fibroblasts. In the present study, we investigated the influence of tamoxifen, and several triphenylethylene derivatives, on protein kinase C (PKC) in MCF-7 human breast cancer cells. As measured by Western blot analysis, tamoxifen elicited isozyme-specific membrane association of PKC-epsilon, which was time-dependent (as early as 5 min post-treatment) and dose-dependent (5.0-20 microM). Tamoxifen did not influence translocation of alpha, beta, gamma, delta or zeta PKC isoforms. Structure-activity relationship studies demonstrated chemical requirements for PKC-epsilon translocation, with tamoxifen, 3-OH-tamoxifen and clomiphene being active. Compounds without the basic amino side chain, such as triphenylethylene, or minus a phenyl group, such as N,N-dimethyl-2-[(4-phenylmethyl)phenoxy]ethanamine, were not active. In vitro cell growth assays showed a correlation between agent-induced PKC-epsilon translocation and inhibition of cell growth. Exposure of cells to clomiphene resulted in apoptosis. Since PKC-epsilon has been associated with cell differentiation and cellular growth-related processes, the antiproliferative influence of tamoxifen on MCF-7 cells may be related to the interaction with PKC-epsilon.

Surface defect passivation for ZnO nanocombs (NCBs), random nanowires (RNWs), and aligned nanowires (ANWs) was performed through a metal plasma immersion ion implantation with low bias voltages ranging from 0to10kV, where Ni was used as the modification ion. The depth of surface-originated green band (GB) emission is thus probed, revealing the surface origin of the GB. It is also found that the GB is closely related to oxygen gas content during growth of the nanostructures. The GB origin of NCBs and RNWs grown with higher oxygen content is shallower (∼0.5nm), which can be completely quenched with no bias applied. However, the GB origin of ANWs grown at lower oxygen content is much deeper (∼7nm) with a complete quenching bias of 10kV. Quenching of the GB can be attributed to passivation of the surface hole or electron trapping sites (oxygen vacancies) by Ni ions.

Single-crystalline, transparent conducting ZnO nanowires were obtained simply by Ti plasma immersion ion implantation (PIII). Electrical transport characterizations demonstrate that the n-type conduction of ZnO nanowire could be tuned by appropriate Ti-PIII. When the energy of PIII is increased, the resistivity of ZnO decreases from 4×102 to 3.3×10−3 Ω cm, indicating a semiconductor-metal transition. The failure-current densities of the metallic ZnO could be up to 2.75×107 A/cm2. Therefore, this facile method may provide an inexpensive alternative to tin doped indium oxide as transparent conducting oxide materials.

One hundred and thirty eight unselected hemodialysis patients were screened for allergic symptoms, atopy, total IgE, eosinophil count, specific IgE against ethylene oxyde (ETO), formaldehyde (FA) and isocyanates (Iso) and delayed hypersensitivity to formaldehyde. Six patients demonstrated hypersensitivity to formaldehyde. Six patients demonstrated hypersensitivity reactions at the beginning of hemodialysis; one had recurrent urticaria and one aggravated a preexistent asthma. There were no predicting factors but 6 out of these 8 patients (62%) had positive RAST against ETO, FA or Iso. Eczematous lesions occurred in 40 patients (20%) mainly located around the fistula. Eczema is significantly more frequent in men, atopic patients, and patients using a type of machine where we measured high residual FA concentrations (greater than 50 mg/l). A positive FA patch test was observed in 22% of the patients with an eczema compared to 1.3% in the asymptomatic patients (p less than 0.01).

This paper will provide data from an investigation of the behavior of a range of concrete mixes made with blended cements stored in seawater. Three cements were used at binder contents of 280, 350, 420, and 550 kg/m³. Ground granulated blast furnace slag was used as a cement replacement. Soluble chloride ion contents were measured using ion chromatography on samples drilled from concrete cylinders in zones 0-10 mm, 20-30 mm and 40-50 mm from the surface. The test results indicated that the dominant parameter with regard to resistance to chloride penetration was binder content. For a particular binder content, chloride ion penetration decreased as the amount of cement replacement increased. Slag appeared to be a very effective cement replacement material for concretes in marine environments. Cement blends with 60 percent cement replacement by slag seemed to be the optimum mixes with respect to combination of strength development and resistance to chloride penetration.