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Background & Aims Tenofovir disoproxil fumarate (TDF) is the preferred treatment to prevent maternal transmission of HBV, owing to its efficacy and safety. However, data are lacking on the long-term safety outcomes in children following fetal exposure to TDF. Methods Children participating in a prospective, multisite trial of maternal TDF treatment during late pregnancy were recruited for follow-up visits once a year. Growth parameters, serum biochemistry, HBV serology, and bone mineral density (BMD) by dual-energy x-ray absorptiometery scan were measured. Results One hundred and twenty-eight children, 71 in the TDF and 57 in the control group, completed 255 follow-up visits at the age of 2 to 7 (median, 4.08) years. No differences in z-scores for weight-for-age (0.26 ± 0.90 vs. 0.22 ± 0.99, p = 0.481), z-scores for height-for-age (0.20 ± 1.02 vs. 0.25 ± 0.98, p = 0.812), and estimated glomerular filtration rate (169.12 ± 50.48 vs. 169.06 ± 34.46 ml/min/1.73m2, p = 0.479) were detected. After adjustment for age, sex and HBV status by multiple linear regression, children in the TDF and control group had comparable levels of serum calcium, phosphorus, bone-specific alkaline phosphatase, calcidiol and BMD of lumbar spines (0.55 ± 0.01 vs. 0.57 ± 0.01 g/cm2, p = 0.159) and left hip (0.56 ± 0.01 vs. 0.56 ± 0.01 g/cm2, p = 0.926). Conclusions Children of HBV-infected mothers who did or did not receive tenofovir disoproxil fumarate treatment during late pregnancy had comparable long-term growth, renal function, and bone development up to 6–7 years after delivery. Clinical trial number NCT01312012 ( ClinicalTrials.gov ) Lay summary Currently there are insufficient long-term safety data in children born to mothers who took antiviral agents during pregnancy to prevent mother-to-infant transmission of hepatitis B virus (HBV). In this study, we found that children of HBV-infected mothers who did or did not receive tenofovir disoproxil fumarate treatment during late pregnancy had comparable long-term growth, renal function, and bone development up to 6-7 years after delivery.

In this paper, we propose a new design of flow channel and stack arrangement based on the numerical study considering the effect of the flow channel design on the stack performance and analyze the thermal stress of a planar anode-supported solid oxide fuel cell stack. We also attempt to simplify the cell stack design without affecting its performance and propose an easier sealing method of cell stacks through the study of the thermal stress distribution. The results indicate that the new design, created by changing the cathode flow channel to a porous current collector, with a 6.3% increase in power density, an 8.6% increase in electrical efficiency. Both more uniform flow and current density distribution can be obtained as compared with a conventional counter-flow design. In addition, we propose a new design direction of cell stack, which could be simpler and easier to fabricate, in which material can easily undertake the resulting stress based on the thermal stress analysis.

This paper presents a robust fault-tolerant H ∞ approach for the development of the energy management strategy (EMS) for a parallel hybrid electric vehicle (PHEV). The objective is to determine the power split ratio between engine and battery that maintains the state of energy (SOE) of the battery within a reasonable range to prevent the battery from undesirable breakdown under the situation of existence of battery fault. The system model which consists of the engine part; the electric motor part and the battery part (here a equivalent circuit model) is given first. Then the control system structure with weighting functions, taking into account the battery fault and the control signal limit, is given. Finally, the controller is derived and some simulations for a specific PHEV are included.

This paper presents an observer-based fault estimation method for the Li-ion battery used for hybrid electric vehicles (HEVs) propulsions, where battery ageing is treated as a fault. First, the nominal equivalent electric circuit (EEC) battery model and the extended one combining the effects of temperature and fault variations are given. Then the principle of fault estimation is stated, the fault observer with the general H ∞ configuration is depicted, some weighting functions for performance description are given. Finally, the fault observer is derived and simulation results both in frequency domain and time domain are given. The simulation results illustrate the availability of the proposed observer which owns excellent robustness performance with respect to disturbances, e.g., electrical current and temperature variations.

24 Mb deletion of 6q22.1--q23.2 in an infant with pulmonary atresia, ventricular septal defect, microcephaly, developmental delay and facial dysmorphism.

This paper presents a hybrid knowledge-based decision support system for enterprise mergers and acquisitions. The HKDSS system provides not only practical merger and acquisition procedures, related regulations, and legal problems but also feasible solutions or actions through the performance of rule-based reasoning. The hybrid system integrates a database, case base, rule base and model base to create a tool that managers can use to deal with decision-making problems via the Internet. Rules in the rule base are explained here in detail to illustrate the process of reasoning, and four practical cases in the case base also used to show how a case can be dealt with as a new case arrives. In order to evaluate a business's value, a discounted free cash flow model and economic profit model in the model base have been developed. Finally, a scenario analysis is employed to show how the user can deal with an uncertain growth rate and present value.

Monolayer-isolated silver (Ag) nanodots with the average diameter down to 7 nm are synthesized on Al2O3/Si substrate by vacuum electron-beam evaporation followed by annealing at 400 degreesC in N-2 ambient. Metal-insulator-silicon (MIS) structures with Ag nanodots embedded in Al2O3 gate dielectric are fabricated. Clear electron storage effect with the flatband voltage shift of 1.3 eV is observed through capacitance-conductance and conductance-voltage measurements. Our results demonstrate the feasibility of applying Ag nanodots for nanocrystal floating-gate memory devices. (C) 2004 Elsevier B.V. All rights reserved.

Large area, self-assembled Au-Si alloy nanocones are synthesized by vacuum electron-beam evaporation method at 450 degreesC. The formation mechanism is discussed based on the stress effect, interface energy, and Au-Si alloying process. The electron field emission properties of the self-assembled nanocones are studied based on current-voltage measurements and the Fowler-Nordheim equation. Low turn-on field (10 V/mum) with relatively high current density is obtained due to the nanocone-shaped structures with relatively rough morphology. The process temperature is lower than the melting point of ordinary glass. So our method is of great significance to the low-cost vacuum field emission devices fabrication. (C) 2003 Elsevier B.V. All rights reserved.

The magneto-optical Kerr effect of single-walled carbon nanotubes (SWNTs) film in the Terahertz region is theoretically studied by means of the Drude model. The calculation shows a new oscillation occurring near the plasma frequency as the origin of the magneto-optical Kerr effect for the single-walled nanotubes film. We propose that the amplitude of this near plasma frequency oscillation is directly proportional to the external magnetic field and its period increases with increasing cyclotron frequency. We consider these features of this oscillation of SWNTs are related to the Landau energy of SWNTs. The reflectivity and figure of merit (FOM) spectrum also reveal that this oscillation is the dominant mechanism for the magneto-optical Kerr effect of SWNTs film. Meanwhile, the shift and large enhancement of Kerr rotation under different external magnetic fields is explained. (C) 2004 Elsevier Ltd. All rights reserved.

A theoretical investigation for the magneto-optical Kerr effect of InSb in Terahertz region is carried out. The results show an enhancement of Kerr effect both at room temperature and a low temperature in Terahertz region. The enhancement of Kerr spectrum due to the plasma edge effect is put forward. Meanwhile, the magneto-optical Kerr effect spectrum of InSb in the different external magnetic fields are discussed. The peak shifts of the Kerr rotation under different external magnetic fields and temperatures are discussed.

High-vacuum electron-beam evaporation method is used for large area, metal-nucleated germanium (Ge) nanodots and nanocones on Si3N4/Si preparation. Nanodot and nanocone arrays with uniform size in bulk-quantity are synthesized using titanium (Ti) nanocrystals as nucleating center at 750degreesC with different Ge deposition amount, respectively. The morphology evolution from nanodot to nanocone is studied by atomic force microscopy (AFM). The structure of the prepared sample is characterized by X-ray diffraction (XRD) and Raman scattering. Ge nanocones formed by this convenient fabrication process could have potential applications on nanoelectronics and vacuum electron field emission. (C) 2003 Elsevier Science Ltd. All rights reserved.

Quaternary InAlGaN film has been grown directly on top of low-temperature-deposited GaN buffer layer by low-pressure metalorganic vapor phase epitaxy. High-resolution X-ray diffraction and photoluminescence (PL) results show that the film has good crystal quality and optical property. Temperature-dependent PL and time-resolved PL (TRPL) have been employed to study the carriers recombination dynamics in the film. The TRPL signals can be well fitted as a stretched exponential function exp[-(t/tau)(beta)] from 14 to 250 K, indicating that the emission is attributed to the radiative recombination of excitons localized in disorder quantum nanostructures such as quantum disks originating from indium (In) clusters or In composition fluctuation. The cross-sectional high-resolution electron microscopy measurement further proves that there exist the disorder quantum nanostructures in the quaternary. By investigating the dependence of the exponential parameter beta on the temperature, it is shown that the multiple trapping-detrapping mechanism dominates the diffusion among the localized states. The localized states are considered to have two-dimensional density of states (DOS) at 250 K, since radiative recombination lifetime tau(r) increases linearly with increasing temperature. (C) 2002 Elsevier Science B.V. All rights reserved.

A new method, high-vacuum electron-beam co-evaporation is used to prepare silicon nanocrystals (Si NCs) embedded in Al2O3 dielectric matrix in the form of thin films. Silicon and Al2O3 are co-evaporated by two electron guns at the same time at room temperature with the pressure below 1×10−5 Pa. After evaporation, annealing in N2 ambient at 500 and 800 °C for 1 h is performed. X-ray diffraction and atomic force microscopy are used to estimate the diameter of the Si NCs and check the morphology of the co-evaporation film respectively. X-ray photoelectron spectroscopy is used to investigate the chemical state of Si and Al in the as-prepared and annealed samples. Electrical properties of the Si NCs are investigated and resonant tunneling due to three dimensional quantum confinements is observed at room temperature.

Background Isoliquiritigenin (ISL) is a natural compound in licorice and has chemopreventive and anti-tumour activities. ISL induces tumour cell apoptosis and DNA damage in cervical cancer cells, and induces ATM-associated DNA repair signalling. However, ISL down-regulates ATM and phosphorylated ATM (p-ATM) in human oral squamous cell carcinoma (OSCC) cell lines. The aim of this study was to investigate the ATM inhibition mechanism of ISL in OSCC cell lines. Methods mRNA and protein expression were detected by reverse transcription-PCR (RT-PCR) and western blotting, respectively. The promoter activity was detected by firefly and renilla luciferase reporter system. DNA damage was analysed by terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay and gamma-H2A.X protein expression. microRNA expression was detected by quantitative RT-PCR. Findings ISL induced OSCC cell cycle G2/M phase arrest, apoptosis, and DNA damage. However, the DNA repair-associated ATM and p-ATM proteins were down-regulated, ATM mRNA levels were unchanged, and the p-ATM downstream signals were inhibited. The down-regulated ATM protein expression might be caused by promoter activity inhibition, microRNA over-expression, and protein degradation. The ATM promoter in OSCC cell line was unchanged after ISL treatment. The microRNAs miR203a and miR421, which target ATM, were both down-regulated. When blocking caspase activity with Z-DVED-FMK, the down-regulation of ATM was reversed. Interpretation ISL-inhibited ATM expression was not regulated by miR203a and miR421 at a transcriptional level. The down-regulation of ATM was caused by ISL activating caspase. These data indicate that ISL induced apoptosis and inhibited DNA repair in OSCC. ISL might be a promising chemopreventive agent against oral cancer.

Purpose: Primary angle-closure glaucoma (PACG) is more prevalent among Chinese than whites. The authors tested the hypothesis that Chinese have shallower anterior chambers than do whites, a factor that may be related to PACG prevalence. Methods: The authors compared anterior chamber depth, axial length, radius of corneal curvature, and refractive error among 531 Chinese, 170 whites, and 188 blacks older than 40 years of age using the same model of instruments and identical technique. Results: Mean anterior chamber depth and axial length did not differ significantly for the three groups. Whites had a significantly higher prevalence of hyperopia >2 diopters than did Chinese. Radius of corneal curvature was significantly smaller among Chinese than whites or blacks. Conclusions: These results suggest that Chinese do not differ on a population basis from other ethnic groups in many of the biometric risk factors known to be of importance for PACG. It will be necessary to identify other ocular biometric parameters to explain the excess burden of PACG among Chinese, which may improve the effectiveness of screening for this disease in all populations.

Two existing rigid band models of low temperature luminescence in a-Si:H are compared and their difficulties examined. A new model is proposed which includes the essential features of both, and which explains the width and Stokes shift of the spectra without problems of large excitation power shifts in peak position.

The conductivity of single-walled nanotube films is investigated with a combination of Maxwell-Garnett (MG) and Drude-Lorentzian (DL) model in terahertz region. A theoretical investigation for the recent experiment is given and a decrease of the real conductivity with increasing frequency is predicted. Meanwhile, the real part of dielectric function of single-walled carbon nanotube films is displayed. (C) 2003 Elsevier Science B.V. All rights reserved.

The modified sol-gel processing technique of free casting provides an attractive route for preparation of low-shrink ceramic monoliths. Sols based on colloidal silica can be rapidly cooled and retain their frozen structure after warming to ambient temperatures. Owing to the large pore size in the gels, cracking is avoided during drying. A selection of silica sols has been examined and the state of aggregation of the particles was established as a critical parameter in determining whether sols can be processed in this way.

The adsorption of nitric oxide by nickel and also nickel surfaces preexposed to oxygen has been studied by X-ray photoelectron spectroscopy in the temperature range 80 to 290 °K. The surface reactivity to NO interaction has been controlled by varying the temperature and conditions of preexposure to oxygen. This has enabled three distinct states of NO adsorption to be delineated, a dissociative state and two molecular states. One of the molecular states is weakly adsorbed while the other, more strongly chemisorbed, is the precursor to dissociation. We suggest the latter is adsorbed in the “bent” form while the former is linearly bonded to the surface. N2O is also observed within the adlayer at 80 °K particularly with nickel surfaces preoxidized at 290 °K. The N2O is weakly adsorbed. There are strong analogies between the present data and previous studies with copper, iron, and aluminum, metals with very different electronic structures. It should be noted, however, that although in all cases a new surface phase is generated, the inherent reactivities of the clean metals differ only in degree rather than in kind.

Let Ω n denote the set of all n × n Hadamard matrices. For H ∈ Ω n , define the weight of H to be w ( H ) = number of 1's in H , and w(n) = max {w(H); H ∈ Ω n } . In this paper, we derive upper and lower bounds for w ( n ).

Calmodulin-dependent cyclic nucleotide phosphodiesterase was purified from bovine brain to apparent homogeneity by a new procedure involving DEAE-cellulose, Affi-Gel blue, calmodulin-Sepharose 4B, and Sephadex G-200 column chromatographies. The enzyme was purified more than 3,000-fold from the brain extracts with greater than 12% yield. The purified phosphodiesterase could be activated 10- to 15-fold by calmodulin and Ca2+ to a specific enzyme activity of more than 300 mumol of cAMP hydrolyzed/min/mg of protein. Molecular weight of the enzyme was determined to be 115,800 by the sedimentation equilibirum method or 124,000 from the sedimentation constant and Stokes radius of the protein. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the enzyme showed a single protein band with an apparent molecular weight of 58,000. These results suggested that the calmodulin-dependent phosphodiesterase from bovine brain has a subunit structure of alpha2. Molecular weight of the complex of calmodulin and phosphodiesterase was the complex of calmodulin and phosphodiesterase was also calculated from the sedimentation constant and Stokes radius to be 159,000. Since calmodulin has a molecular weight of about 17,000, the result indicated that the stoichiometry of the complex is calmodulin2 alpha2. The catalytic subunit of cylic AMP-dependent protein kinase was found to catalyze the phosphorylation of the purified phosphodiesterase with the incorporation of 2 mol of phosphate/mol of the enzyme.