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Co substituted nanonickel hydroxide, which used NiCl2 and Na2CO3 as nickel source and buffer respectively, was synthesised by ultrasonic method. XRD, TEM, PSD and EDS were used to characterise the physical and electrochemical performance of the prepared samples respectively. The electrochemical performance affected by Co substituted ratio and buffer content were determined by cyclic voltammogram and discharge–charge test. The results demonstrated that the Co substituted nanonickel hydroxide was the mixed phase of α- and β-Ni(OH)2 and the increasing Co content led to the larger proportion of α-nickel hydroxide. An increase in Na2CO3 content was beneficial to form α-nickel hydroxide. The morphology of all samples was the needle-like and the length/diameter ratio decreased with increasing Na2CO3 content. Composite electrodes were made by mixing 8 wt-% nickel hydroxide with commercial β-nickel hydroxide. The discharge capacities of electrodes first increased and then decreased with the change of Na2CO...

GH4169 alloy was shot-peened with processing durations of 3 min and 10 min. The effects of dry and wet shot peening on the microstructure and residual stress were investigated. The results demonstrated that a severely deformed layer manifests on the surface of the shot-peened GH4169 alloy samples. Compared with the dry-peening samples, the surface defects of wet-peening samples obviously decrease. With the shot peening treated for 10 min, the surface microhardness of the dry peening and the wet shot peening increased by 20% and 17% respectively compared with the original surface hardness. The deformation mechanisms of the GH4169 alloy could be attributed to dislocation and deformation twining, as detected by TEM observations. Compressive residual stress was introduced into the surface layer of the shot-peened GH4169 alloy. The maximum surface residual compressive stress (SRS) and maximum residual compressive stress (MRS) were -586 MPa and -795 MPa, respectively. The MRS and SRS were improved with increasing processing duration. The SRS of the wet-treated specimens was slightly higher than that of the dry-treated samples under the same processing parameters. However, the MRS of dry-treated samples was much larger than that of the wet-treated samples due to the higher shot intensity.

The oriental leafworm moth, Spodoptera litura, is a major agricultural pest in southeast Asia and nearby Pacific regions. Two distinct trehalases have been identified in insects: soluble trehalase (Treh1) and membrane-bound trehalase (Treh2), although there is currently no information on these genes in S. litura. To characterize the distribution and function of treh, cDNAs of Treh proteins were cloned from S. litura. SpoliTreh1 cDNA has an open reading frame of 1758 nucleotides, which encodes a protein of 585 amino acids, with a predicted mass of approximately 67.07 kDa and an isoelectric point of 4.86. SpoliTreh2 cDNA has an open reading frame of 2325 nucleotides, encoding a protein of 645 amino acids, a mass of approximately 73.62 kDa, and an isoelectric point of 5.90. Northern blotting analysis revealed that SpoliTreh1 transcripts are in the midgut, fat body, tracheae, and epidermis, but not in the brain and Malpighian tubules of S. litura larvae, whereas SpoliTreh2 transcripts were found in all 6 tissues. SpoliTreh1 transcripts were highly expressed in the fat body of the pre-pupal stage, and SpoliTreh2 transcripts were highly expressed in the fat body of 3-day-old larvae of the 6th instar and during the 1st 6 days of the pupal stage, except the 2nd day. Both SpoliTreh1 and SpoliTreh2 were highly expressed in third-instar larvae.

We describe the epidemiology of hepatitis B virus (HBV) infection among women of reproductive age residing in areas of China that are highly endemic for chronic HBV, and provide evidence useful for decision-makers to guide strategies for preventing mother-to-child transmission of HBV, and assess the impact of perinatal transmission PMTCT by projecting HBsAg prevalence trends without interventions. We conducted a cross-sectional HBV serological survey of women, 15-49 years of age, residing in Fujian, Guangdong, Guangxi and Hainan provinces. Demographic and other subject-level data were collected in face-to-face interviews, after which we obtain blood specimens. Specimens were tested for HBV sero-markers by ELISA (Beijing Wantai Biological Pharmacy), and HBV DNA was tested with PCR (Hunan Sansure Biotech). Weighted HBsAg and HBV (either HBsAg+ or anti-HBc+ indicating either present or past infection) prevalences were 11.82% and 57.16%, respectively. Among the HBsAg-positive women, 27% were also HBeAg positive. The proportion of individuals with HBV DNA loads >105 IU/mL declined with increasing age. Among HBsAg-negative women, 0.9% had occult HBV infection. The prevalence of chronic HBV infection among reproductive women in these highly endemic provinces is high, posing a threat to maternal health and risk of mother-to-child transmission. Prevention of mother-to-child transmission remains critically important.

In this paper we report the novel assembly method of a biosensor unit based on 64 pixel photodetector array with a proprietary semiconductor quantum dots (QDs) quantum well (QW) hybrid structure. There is significantly lower dark current for optimized high sensitivity detector. The capacitive trans-impedance amplifier (CTIA)-correlated double sampling (CDS) readout circuit can readout weak optical signal which respond by photodetector. To minimize the packaging size of our biosensor unit, a double-sided printed circuit board designed to decrease noise by special package making photodetector array can operate at room temperature and lower temperature for get better performance. The readout circuit is bonding on the backside of substrate through silicon via (TSV) structure, and the photodetector array bonding on the front side of substrate for making the optic signal through to photosensitive window of detector. A highly integrated Cortex-M4 MCU (STM32F407) has build the data acquisition and analysis unit providing Wi-Fi interface to communicate with the PC software for biosensor unit rapid diagnosis infectious disease and more easy carry.

A nonequilibrium Green's-function formalism is employed to study the time-dependent transport through resonant-tunneling structures. With this formalism, we derive a time-dependent Landauer-Buttiker formula that guarantees current conservation and gauge invariance. Furthermore, we apply the formula to calculate the response behaviors of the resonant-tunneling structures in the presence of rectangular-pulse and harmonic-modulation fields. The results show that the displacement current plays the role of retarding the tunneling current.

SUMMARY Pre-eclampsia is an endothelial disorder and TNF-α has fundamental effects on endothelial cells by several means, including altering the balance between oxidant and anti-oxidant, changing the pattern of prostaglandin production and affecting expression of several cell surface components. To determine whether TNF-α mRNA expression is increased in pre-eclamptic patients, leucocytes from pre-eclamptic patients, normal pregnant women and normal non-pregnant women were studied for TNF-α expression using a quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method. Using a model of 373A ABI Sequencer, TNF-α gene polymorphism was also analysed by GENESCAN and Genotyper software in order to explain the mechanism of abnormal TNF-α expression. Our results show that TNF-α mRNA expression is significantly elevated in pre-eclamptic patients compared with the other two control groups. The high expression of TNF-α may be associated with the TNF1 allele, whose frequency is markedly increased in pre-eclamptic patients. These observations are consistent with a major role for TNF-α in mediating endothelial disturbances, and suggest a key role for TNF-α in the development of pre-eclampsia.

We investigate the quantum dynamics of the quantum-dot cellular automata qubit in the presence of a quantum point contact detector by modified rate equations. It is demonstrated that the qubit information can be resolved by measuring the detector current variation. Furthermore, we show that this oscillating current and the electron occupation probabilities in states |b〉 and |c〉 decay drastically as the dephasing rate increases, clearly revealing the influence of the dephasing induced by the detector. Moreover, it is shown that the operation speed of the quantum-dot cellular automata qubit may be adjusted by varying the interdot coupling strength.

Electronic band structures and spin states of the InAs/GaAs quantum dots (QDs) induced by the wetting-layer fluctuation were investigated by employing the technique of time-resolved Kerr rotation (TRKR) with and without magnetic field. Sign change of the Kerr rotation signal was unambiguously observed when only the wavelength of the pump/probe light was scanned. By carefully examining the dependence of TRKR signal on the excitation wavelength and magnetic field as well as photoluminescence and reflectance spectra, the physical origin causing the sign change of the Kerr signal is uncovered. It is due to the resonant excitations of electrons with opposite spin orientations at heavy- (hh) and light-hole (lh) subbands, respectively, since there is a large enough energy separation in QDs for the excitation laser pulses. This measurement also leads to a precise determination of the energy separation between the hh and lh subbands near k 0 point in the dots. © 2011 American Institute of Physics.

We derive the modified rate equations for an Aharonov-Bohm (AB) ring with two transversely coupled quantum dots (QD's) embedded in two arms in the presence of a magnetic field. We find that the interdot coupling between the two QD's can cause a temporal oscillation in electron occupation at the initial stage of the quantum dynamics, while the source-drain current decays monotonically to a stationary value. On the other hand, the interdot coupling equivalently divides the AB ring into two coupled subrings. That also destroys the normal AB oscillations with a period of 2pi, and generates new and complex periodic oscillations with their periods varying in a linear manner as the ratio between two magnetic fluxes (each penetrates one AB subring) increases. Furthermore, the interference between two subrings is also evident from the observation of the perturbed fundamental AB oscillation.

Ischemia reperfusion injury (IRI) model of rat heart was prepared by preperfusion for 15 min, then a suspension for 45 min and recycling reperfusion for 15 min with 30 ml KH buffer. The leakage of lactate dehydrogenase(LDH),protein, myoglobin and nitrite (NO2-) in the circular perfusion fluid were measured. Myocardial nitric oxide synthase(NOS) activity and L-arginine transport were observed. In the IR group, the leakage of LDH,protein, myoglobin and NO2- were increased respectively by 4.1,5.4,1 and 1.2 times(P0.01) and NOS(tNOS, iNOS, cNOS) activity by 48.2%,43.2% and 52.1%,(P0.01,respectively) as compared with the control group. L-arginine transport might be mediated by either high- or low-affinity transport system in cardiac tissue. In the IR group, L-arginine transport increased significantly with the V(max) being increased by 48% and 2 times respectively for the low-affinity and the high-affinity transport as compared with control. Michaelis constant (km) was decreased by 47.4% for low-affinity transport (P0.05),but not significantly changed for the high-affinity transport. These results suggest that the increase of nitric oxide generation might result from the increased myocardial NOS activity and L-arginine transport during IRI.

Changes of L-arginine/nitric oxide pathway in heart and of L arginine transport in erythrocytes and their relationship were investigated in spontaneously hypertensive rats (SHR). 12 and 16 weeks old SHR, 16 weeks old SHR with captopril treatment for 4 weeks and 16 weeks old Wistar-Kyoto (WKY) rats were used. L arginine transport of myocardial ventricular tissue and erythrocytes, total nitric oxide synthase (tNOS) activity, nitrite and nitrate (NO(2) + NO(3)) and cyclic GMP (cGMP) content in myocardium were measured. The result showed that in myocardial ventricular tissue of SHR L-arginine transport decreased significantly with V(max) of the high-affinity transport being decreased by 24.3% (P0.05, 12W group), 36.4% (P0.01, 16W group) as compared with WKY group. Michaelis constant (K(m)) of low affinity transport was significantly lower than that of WKY group. NO(2) + NO(3) and cGMP content were respectively decreased by 24.6%, 19.8% (P0.05, P0.05, 12W group), 52.5%, 60.4% (P0.05, P0.01, 16W group) and 14.8%, 23% (P0.05, P0.05, SHR+C group) as compared with WKY group. But the K(m) of L-arginine high-affinity transport and the V(max) of low affinity transport and tNOS activity were not significantly changed. In erythrocytes, the changes of L-arginine transport coincided with those of myocardial tissue. The V(max) had significant positive correlation with the V(max) of high-affinity transport in myocardial tissue, r=0.5606, P=0.01 and had negative correlation with left ventricular weight to body weight radio, r=0.6231,P0.01. These results indicate that the activity of L-arginine/nitric oxide pathway inhibited in myocardial tissue of SHR. The correlation between the inhibitory degree of L-arginine/nitric oxide pathway and the degree of ventricular hypertrophy is negative. The changes of L-arginine transport in erythrocytes coincide with those in myocardium.

We derive the generalized rate equation for the coupled quantum-dot (QD) system irradiated by a microwave field in the presence of a quantum point contact. It is shown that when a microwave field is tuned in resonance with the energy difference between the ground states of two QD's, the photon-assisted tunneling occurs and, as a result, the coupled QD system may be used as the single qubit. Furthermore, we show that the oscillating current through the detector decays drastically as the dephasing rate increases, indicating clearly the influence of the dephasing effect induced by the quantum point contact used as a detecting device.

By constructing a GaMnAs epilayer/semi-insulating In0.2Ga0.8As/(001) n+-GaAs substrate layer structure as a built-in p-i-n photodiode, we developed a scheme for on-chip measurements of transmission magnetic circular dichroism (T-MCD). Both the hysteresis loops in the magnetic field sweeps and the wavelength scans at saturated magnetic fields measured using the new T-MCD scheme, illustrated the same features as those previously measured on the freestanding GaMnAs thin films by conventional T-MCD. Because a large group of epitaxially grown magnetic film/semiconductor heterostructures, such as Fe, NiFe, CoFeAl, and MnGa films on semiconductor substrates, are becoming important new building blocks for semiconductor-based spin field-effect transistor, perpendicular magnetic tunnel junction (p-MTJ) and lateral MTJ devices, the new T-MCD scheme can be applied to tests of their magnetic properties by forming either p-i-n or Schottky photodiodes.

The signal transduction pathways of the inhibitory effect of nitric oxide (NO) on endothelin (ET)-induced proliferation of vascular smooth muscle cells (VSMCs) were studied. 3H-thymidine (TdR) incorporation, mitogen-activated protein kinase (MAPK) activity and protein kinase C (PKC) activity of cultured VSMCs of rabbits thoracic aorta were measured in the presence of either NO precursor L-arginine (L-Arg) or NO donor 3-morpholino sydnonimine-hydrochloride (SIN-1), or ET-1 alone or with L-Arg or SIN-1. The results show: (1) ET-1 (10(-8) mol/L) significantly increased VSMCs 3H-TdR incorporation (5 times, P0.01), MAPK activity (4 times, P0.01) and PKC activity (3 times, P0.01), as compared with control. L-Arg or SIN-1 alone was without effect on 3H-TdR incorporation, MAPK activity and PKC activity. (2) When ET-1 and L-Arg (2, 5, 10 mmol/L) were simultaneously administered, 3H-TdR incorporation and activity of both MAPK and PKC were all significantly decreased in comparison with the ET group. (3) When ET-1 + SIN-1 (5, 10, 50 mumol/L), the effects coincide with those of the ET-1 + L-Arg groups. These findings indicate that NO inhibition of the signal transduction pathways of the ET-1-induced proliferation of VSMCs may be mediated by the inhibition of ET-1-induced activation of both PKC and MAPK.

To Investigate the myocardial ultrastructure effects of SMT on the ischemia reperfusion injury (IRI) in the rat heart.Eighteen Spraqua-Dawley rats were randomly divided into three groups: ischemia reperfusion group (IR), subjected to 60 min of o-cclusion and 20 min of reperfusion of the anterior descending branch of left coronary artery; IR + SMT group (SMT), given the selective iNOS inhibitor S-methylisothiourea sulfate (SMT, 5 mg/kg, i.v.) before reperfusion; control group (C), didn't occlude coronary artery after exposing heart and observed 80 min. Electrocardiogram (ECG) was recorded. Nitrite and nitrate content were measured in myocardium and blood serum. The changes of myocardial ultrastructure were observed with electron microscope.Ischemia reperfusion induced ST segment elevation and T waves inversion or tallness in ECG, damaged myocardial ultrastructure, increased nitrite and nitrate content in myocardium and blood serum after IR compared with before IR(P0.01). Administration of SMT improved the changes of ECG and the injury of myocardial ultrastructure. Nitrite and nitrate content of myocardium were lower than IR group (P0.05). The change of nitrite and nitrate level of blood serum in SMT group was nearly in C group.SMT can prevent myocardium injury from reperfusion following ischemia.

Nine pairs of dogs were operated with head cross circulation and four pairs of dogs with brain cross circulation. Bleeding of formoral artery decreased the mean arterial pressure to 5.33 kPa and maintained for 30 min. In each pair of A dog 10% of total blood lose was infused intravenously by 7.5% NaCl solution (as test) or normal saline (as control), but B dog was not treated. The results showed that in the test group the arterial blood pressure recovered immediately in both A and B dogs and lasted for more than 60 min after infusion. The recovery value of systolic pressure was higher than diastolic pressure and pulse pressure increased. In the control group the blood pressure recovered slightly but of no statistical significance. There was no remarkable difference in heart rate between the two groups. A marked decrease in hematocrit appeared after bleeding and infusion, but there was no significant difference between the two groups (P0.05). Plasma sodium increased significantly after infusion in A dogs of the test group (P0.01), but the change in B dogs was the same in the control group. These results mentioned above indicate that the central nervous system plays important role on the mechanism of pressor response induced by infusing 7.5% NaCl solution in the hemorrhagic hypotension dog.

A type of manganese impurity center with two holes bound in it is disclosed in a lightly Mn-doped base layer of an n-i-p-i-n heterostructure. In addition to the intensively investigated (e, AMn0) peak, a photoluminescence (PL) peak appears at 820.3 nm under zero bias and is continuously shifted to 822.5 nm by negatively biasing the structure. Its circular polarization has the same polarity as PL (e, AMn0), and has a magnetic dependence fitted by a paramagnetic Brillouin function with S = 1/2 and g = 2.09. These observations are consistent with the physical picture that in the AMn+ center both the − 3/2 and the − 1/2 holes occupy the lowest 1S hydrogenic orbit with their spins parallel to each other and antiparallel to the 5/2 local spin of the 3d shell. This spin coupling picture in the AMn+ center has been confirmed by a modified numerical calculation based upon effective mass theory. The feature of the ability to tune the impurity level of the AMn+ center makes it attractive for optically and electrical...

We investigate the spin-polarized transport properties of a two-dimensional electron gas in a n-type diluted magnetic narrow gap semiconductor quantum well subjected to a perpendicular magnetic and electric field. Interesting beating patterns in the magneto resistance are found which can be tuned significantly by varying the electric field. A resonant enhancement of spin-polarized current is found which is induced by the competition between the s-d exchange interaction and the Rashba effect [Y. A. Bychkov and E. I. Rashba, J. Phys. C 17, 6039 (1984)]., 4 pages, 3 figures, Appl. Phys. Lett. (in press)

Zinc-blende CrSb (zb-CrSb) layers with room-temperature ferromagnetism have been grown on (In,Ga)As buffer layers epitaxially prepared on (001) GaAs substrates by molecular-beam epitaxy. Compared with the typical thickness [2-3 ML (ML denotes monolayers)] of zb-CrSb grown directly on GaAs, the thickness of zb-CrSb grown on (In,Ga)As has been increased largely; the maximum can be up to similar to 9 ML. High-resolution cross sectional transmission electron microscopy images show that the zb-CrSb layer is combined with (In,Ga)As buffer layer without any dislocations at the interface. (C) 2006 American Institute of Physics.

The transport property of a lateral two-dimensional diluted magnetic semiconductor electron gas under a spatially periodic magnetic field is investigated theoretically. We find that the electron Fermi velocity along the modulation direction is highly spin-dependent even if the spin polarization of the carrier population is negligibly small. It turns out that this spin-polarized Fermi velocity alone can lead to a strong spin polarization of the current, which is still robust against the energy broadening effect induced by the impurity scattering., 3 pages, 3 figures, submitted to Appl. Phys. Lett

We have studied magnetic and transport properties of insulating and metallic (Ga,Mn)As layers before and after annealing. A dramatic increase of the ferromagnetic transition temperature T-C by postgrowth annealing has been realized in both insulating and metallic (Ga,Mn)As. The as-grown insulating (Ga,Mn)As can be turned into metallic by the low-temperature annealing. For all the metallic (Ga,Mn)As, a characteristic feature in the temperature dependence of sheet resistance appears around T-C. This phenomenon may provide a simple and more convenient method to determine the T-C of metallic (Ga,Mn)As compared with superconducting quantum interference device (SQUID) measurement. Moreover, the T-C of the metallic (Ga,Mn)As obtained by this way is in good agreement with that measured by a SQUID magnetometer. (C) 2005 American Institute of Physics.

Analyses of sister chromatid exchanges (SCE) were conducted in the maternal and embryonic tissues substituted in vivo with 5-iodo-deoxyuridine (IudR) by implantation of a IudR tablet (40 mg/tablet) in pregnant mice at mid-gestation. Following maternal exposure to 4.2 mg/kg, 2.1 mg/kg, 0.525 mg/kg “Progestogen No. 1” and 20 mg/kg cyclosphosphamide, SCE analyses were conducted in maternal bone marrow and embryonic liver cells.

This review volume consists of scientific articles representing the frontier and most advanced progress in the field of semiconductor physics and lattice dynamics.