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The strained-Si:C long channel MOSFET on a relaxed SiGe buffer is demonstrated in this study. The extracted electron mobility showed an enhancement of ~40% with the incorporation of 0.25% carbon in strained-Si long channel NMOSFETs. However, no improvement was seen in the output characteristics of the strained-Si:C PMOSFET. The performance enhancement seen is less than the theoretical prediction for increasing carbon content; this is due to the high alloy scattering potential with carbon incorporation, high interface state density (D it ) at the oxide/strained-Si:C interface and interstitial carbon induced Coulomb scattering. However, increased amounts of C may result in degraded device performance. Therefore, a balance must be struck to minimize C-induced extra Coulomb and alloy scattering rates in the fabrication of these devices.

Angiogenesis and hematopoiesis are closely linked and interactive with each other, but few studies were given to identify possible links between angiogenesis-promoting proteins and hematopoiesis-related transcription factors. Here we investigated the potential relationship of oxygen-sensitive alpha-subunit of angiogenesis-related hypoxia-inducible factor-1alpha (HIF-1alpha) with Runt-related protein 1 (Runx1, also known as acute myeloid leukemia-1, AML-1), an important hematopoietic transcription factor. The results demonstrated that Runx1 and HIF-1alpha proteins directly interacted with each other to a degree, in which Runt homology domain of Runx1 was mainly involved. Leukemia-related abnormal Runx1 fusion protein AML1-ETO, which fuses the N-terminal 177 amino acid residues of the Runx1 protein in frame to ETO (eight-twenty-one) protein, also interacted with HIF-1alpha protein with greater ability than Runx1 itself. More intriguingly, Runx1 overexpression inhibited DNA-binding and transcriptional activity of HIF-1 protein with reduced expression of HIF-1-targeted genes such as vascular endothelial growth factor, while silence of Runx1 expression by specific small interfering RNA significantly increased transcriptional activity of HIF-1 protein, suggesting that Runx1 inhibited transcription-dependent function of HIF-1. Vice versa, HIF-1alpha increased DNA-binding ability and transcriptional activity of Runx1 protein. All these data would shed new insight to understanding Runx1 and HIF-1alpha-related hematopoietic cell differentiation and angiogenesis.

We present an analytical calculation of the shape of the magnetoresistive response of spin-valve structures with synthetic antiferromagnetic pinned layer, i.e., of the form buffer/ferromagnet1/Cu/ferromagnet2/Ru/ferromagnet3/antiferromagnet. The magnetization reversal in the three magnetic layers is assumed to occur via coherent rotation. An analytical expression of the whole hysteresis loop is given as a function of the characteristic parameters of the system (coupling strength through the Ru spacer, ferromagnet3/antiferromagnet pinning energy). We also extended a code based on the Boltzmann equation of transport to calculate the giant magnetoresistance (GMR) amplitude in these structures from the microscopic transport parameters. In order to explain the relatively high GMR amplitude experimentally observed in such spin valves, it is shown that some degree of specular reflection must be introduced at the ferromagnet2/Ru interface. Good agreement with both the shape and amplitude of the experimental magnetoresistance curves can be obtained.

For spin valve heads, the conventional anisotropic magnetoresistance (AMR) effect deteriorates the linearity of transfer curves and degrades its performance. This problem is more severe for thicker free layer spin valve. In this paper, giant magnetoresistance (GMR) and AMR effect of a spin valve structure with laminated free layer (seed/Fa/I/Fb/Cu/AP1/Ru/AP2/AFM/cap, I is a thin high resistive layer) were calculated using semiclassical transport model. It is found that the GMR of spin valve structure with laminated free layer is reduced slightly and DR is comparable with the standard one due to the increase of the sheet resistance. The AMR of the laminated free layer reduced dramatically due to the effective magnetic thickness reduction. Therefore, the AMR/GMR ratio in spin valve was greatly reduced. Film level experimental data confirmed the simulation results. As an example, the AMR of 80 /spl Aring/, 65 /spl Aring/ thickness free layer reduced from 1.6, 1.2% to 0.74, 0.6%, respectively, while GMR ratio reduced slightly due to lamination of free layer. The AMR effect of spin valve structure can be reduced by 50% through the lamination of the free layer. It can be expected that the linearity of the transfer curves can be improved greatly.

Proton exchange membrane fuel cells (PEMFC) have received attention owing to their low operating temperature and quick start-up. Fuel cells have high material costs, low power density and short lifetime, which are major barriers to their use. In order to become commercially viable, PEMFC bipolar plates must be cheaper, lighter, and more compact. Here, carbon nanotubes (CNTs) are assessed as a reinforcement for either thermoplastic or thermoset-based nanocomposite bipolar plates, because of such properties as superior mechanical strength, high electrical and thermal properties, and light weight. CNTs have strong intrinsic van der Waals forces with each other, which hold together in ropes and bundles, resulting in very low solubility in most solvents. Therefore, homogeneous dispersion of CNTs in the matrix is key. How to achieve homogeneous dispersion of CNTs by chemical modification is discussed. Owing to the formation of effective 3D electrical conducting networks better properties are obtained such as high mechanical strength, improved electrical conductivity and cell performance when the functionalized CNT is incorporated in a bipolar plate. Functionalized CNT reinforcement is a promising method to manufacture alternative high performance bipolar plates for PEM fuel cell applications.

We set up a high-Tc SQUID system for magnetocardiography (MCG) in a moderately magnetically shielded room. The electronically balanced gradiometer consists of superconducting quantum interference device (SQUID) magnetometer. One reference SQUID was mounted above the sensing SQUID while the sensing SQUID is seated at the bottom of the cryostat. The baseline of the gradiometer is varied from 5 cm to 7 cm. The output of the MCG signal was filtered with the band pass filter (0.5 - 40 Hz) and the power-line filter. The MCG system was used to detect the magnetic signal of the human heart. Equivalent current sources were used to study the inverse problem.

A high-Tc 1st-order electronic superconducting quantum interference device (SQUID) gradiometer system is constructed to study the magnetocardiogram (MCG) of rabbits in a moderately magnetically shielded environment with active compensation. In the noisy hospital environment, the noise cannot be completely reduced with the 1st-order gradiometer, therefore, a reference SQUID with active compensation was used to further reduce the noise level leaking into the room. The MCG system was equipped with a x-y translation bed. We used a low-pass filter with the cut off frequency at 44 Hz, a high-pass filter with the cut off frequency at 0.1 Hz and the 60 Hz notch filter to reduce the power line interference. The noise level of the 1st order gradiometer MCG system in this moderately magnetically shielded room was about 1 pT/square root of Hz1/2 at 1 Hz. The MCG of a normal rabbits was measured with this system and a MCG contour map and a current density distribution was constructed.

AlGaInP light‐emitting diodes (LEDs) with external quantum efficiencies ≥6% and luminous performance of 20 lm/W have been fabricated. These LEDs are twice as efficient as previously reported AlGaInP devices throughout the spectral region from green (555 nm) to red‐orange (620 nm) owing to a thicker GaP window layer (45 vs 15 μm). Using hydride vapor phase epitaxy, thick GaP window layers were grown on top of AlGaInP double heterostructures grown by organometallic vapor phase epitaxy. The efficiency of the LEDs was found to improve as the thickness of the window layer was increased from 9 to 63 μm. This improvement is predicted by a simple model that considers the benefit of enhanced emission through the sides of the thick window. The effect of emission wavelength on quantum efficiency and luminous performance for AlGaInP LEDs with a 45 μm thick window has been studied.

Neonatal Tetanus (NT) has been set by WHO as one of the most important diseases to be under control. Its incidence rate at some counties and cities in Southern Fujian province exceeded set out levels. Both retrospective and cohort studies were carried. It was found that in rural areas only 8.66% (319/3,683) pregnant women gave births at hospital and 94.85% (129/136) NT cases were delivered by untrained midwives. When TAT was tested in mothers and newborns, only 23.81% and 20.65% of them reached protective level. This shows the main reasons for high NT incidence rate were due to poor medical treatment during delivery and low antibody level. Using tetanus toxin (TT) to fully immunize pregnant women, no side effects were observed and TAT antibody levels for mothers and newborns were increasing to reach 100% (99/99) and 93.94% (93/99) relatively. When immunizing women at child-bearing age with TT, 90.40% (113/125) of them still had TAT up to protective level in 3 years. A total number of 8,882 newborns whose mothers had been fully vaccinated with TT were investigated, no NT case occurred. Among 4,835 newborns whose mothers did not receive vaccination, some NT cases were identified. The incidence rate was as high as 5.28%. These results showed that the TT vaccination in women at child-bearing age should be considered as the major strategy for NT prevention.

The disposition of [14C]piritrexim ([14C]PTX) in male dogs after iv and po doses of 1.8 mg/kg was examined. After either route of administration, greater than 90% of the dose was recovered in the exreta within 72 hr; approximately 20% was recovered in urine and 70% in feces. [14C]PTX was extensively metabolized by dogs; unchanged drug accounted for less than 15% of the dose in the excreta. The O-demethylated metabolites, 2'- and 5'-demethyl PTX, the glucuronide conjugate of 2'-demethyl PTX, and the sulfate conjugate of 5'-demethyl PTX were the major metabolites. Unchanged drug accounted for a large proportion of the drug-related radiocarbon in plasma. The average plasma half-life of PTX after iv administration was 2.6 +/- 0.3 hr, and the average total body clearance was 0.33 +/- 0.13 liter/hr/kg. After po administration, peak plasma concentrations of 0.9 +/- 0.3 micrograms/ml occurred about 1.1 hr after the dose; the absolute oral bioavailability of PTX was 0.63 +/- 0.14. Because the O-demethyl metabolites were active dihydrofolate reductase inhibitors, 2'- and 5'-demethyl PTX were synthesized, and the pharmacokinetics and bioavailability of these compounds in dogs after iv and po administration (5 mg/kg) were examined. The plasma concentration-time data for both compounds after iv doses were described by a two-compartment model, with t1/2 beta = 1.3 and 0.8 hr for the 2'- and 5'- demethyl compounds, respectively. Neither compound showed significant advantages over PTX in terms of pharmacokinetics or bioavailability.

We investigated the effect of specular reflection on the anisotropic magnetoresistance (AMR) of magnetic thin films. The sheet conductance is calculated as a function of the angle between magnetization and current from the microscopic transport parameters by using an extension of the Fuchs–Sondheimer theory. The calculation combines specular reflection on the film interfaces with mean-free paths which depend on the angle between the local magnetization and the electron velocity. The theoretical results are compared with experimental ones. Specular reflection can explain the quite large AMR amplitude observed in thin NiFe films used in the last generation of AMR heads.

Ion implantation of Si and Se donors in In0.53Ga0.47As is reported. Both room‐temperature and elevated temperature (200 °C) implants are performed. Rapid thermal annealing as well as conventional furnace anneals have been used. Both species yield relatively shallow profiles with peak electron concentrations ∼1×1019 cm−3 and with sheet resistance less than 20 Ω/sq. Our results indicate that elevated temperature implants are effective in reducing implant damage and are important for heavy ions like Se+ to achieve high activation and mobility.

The temperature dependence of the forward current‐voltage characteristics of Be‐implanted p+‐n junctions in In0.53Ga0.47As is presented. The results are interpreted on the basis of a diffusion current component and a recombination current component. The best diodes obey a pure diffusion current equation, J=J0(T)exp(qV/kT) for a current range of five decades and for temperatures above 200 K.

We describe a native oxide insulated gate, inversion mode In0.53Ga0.47As field‐effect transistor. Drain characteristics measured with pulsed gate voltage yield gm of 33 mS/mm and an effective saturated drift velocity for inversion layer electrons of 2.6×106 cm/s. The presence of a slow drift in drain current is found to reduce the transconductance to 20 mS/mm for low‐frequency measurements.

Ion implantation doping of Be acceptors in n‐In0.53Ga0.47As is reported. A significant improvement in peak concentration, depth control, and solubility is achieved with rapid (30 s) thermal anneals compared to conventional 15‐min furnace anneals, resulting in p‐n junction depths less than 1 μm with peak acceptor concentrations greater than 1018 cm−3. Electrical profiles and p‐n junction characteristics are presented.

The bioavailability of pseudoephedrine and triprolidine from combination and single-ingredient products was evaluated in a randomized, four-way crossover study. Healthy men volunteers received single doses of a tablet containing triprolidine hydrochloride and pseudoephedrine hydrochloride, a syrup containing the same two drugs, and single-ingredient tablets of each drug. Blood samples were collected before each dose and at 13 sampling times over 24 hours for determination of drug concentrations by radioimmunoassay. Observed peak concentration (Cmax), corresponding observed peak time (tmax), area under the plasma drug concentration-time curve from dosing to time infinity (AUC), and the ratio between plasma clearance and extent of bioavailability (CL/F) were determined. Nonlinear regression analysis was used to obtain estimates of lag time for absorption, first-order rate constant for absorption, first-order rate constant for elimination, and ratio between volume of distribution and extent of bioavailability. Data were analyzed for 19 of 20 men entering the study; data were complete for 16 of these. Pseudoephedrine concentrations were significantly different for the combination tablet and the syrup at four sampling times; no significant differences were found between pseudoephedrine concentrations for the combination tablet and single-ingredient tablet. Cmax, tmax, AUC, and CL/F for pseudoephedrine were not significantly different for the three formulations. Triprolidine concentrations at 8 hours were significantly higher for the combination tablet than for the single-ingredient tablet, and tmax for triprolidine was significantly higher for the combination tablet than for the syrup. For both pseudoephedrine and triprolidine, the combination tablet was bioequivalent to the syrup and to the single-drug tablets.

A method designed to quantitate in vivo naltrexone release rates from sustained-release systems has been applied to the evaluation of seven different naltrexone delivery systems in the monkey. The method consists of two phases: a single intravenous bolus dose quantitation of each monkey's pharmacokinetic parameters coupled with a delivery system study in which plasma naltrexone levels are measured throughout the time period of sustained-release. In vivo release rates and the total amount released are then calculated. It should be noted that these determinations require the analysis of unchanged naltrexone in plasma as the only experimental measurement. Data from injectable naltrexone pamoate microcapsule delivery systems indicate that 1) when these microcapsules are suspended in an aqueous vehicle, a significant part of the dose is released very rapidly, yielding release rate-time data that parallel a non-sustained-release control; 2) this rapid release for the aqueous vehicle is followed by a slow release phase lasting to about 24 days for the subcutaneous route and to about 45 days for the intramuscular route; and 3) when these microcapsules are suspended in an oily vehicle there is no initial rapid release, substantial release rates are obtained for at least 60 days, and an average of 89% of the dose is calculated to have been released. Data from implantable naltrexone delivery systems show that 1) the Alza system most closely approximates a zero-order release rate-time profile; 2) the Battelle system provides a rapid initial release followed by a slowly declining release rate; 3) the Dynatech system is characterized by a more rapid initial release rate of 3-8% of the dose per day over the first 3-5 days followed by a rather constant 1-3% per day to about day 36; and 4) essentially complete recovery of the dose was obtained for the Battelle and Dynatech systems.

In this letter we report the first direct measurements of low field transport properties for inversion layer electrons in an InGaAs native oxide metal‐oxide‐semiconductor structure. Our results show that these electrons have a low field mobility which varies from 3000 to 4500 cm2/Vs, compared with 1500 cm2/Vs measured in field‐effect transistor structures. We also deduce a surface state density NSS =1.5×1013 cm−2 eV−1 near the conduction‐band edge.