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The clearance flow of pump-turbine has significant influence on hydraulic forces of the runner, which is related to safety of the unit. To clarify the influence factors, clearance flowrate and clearance hydraulic axial force of a prototype pump-turbine were analyzed by 3D CFD simulations. The results show that the rotational speed, and the smallest radial sizes of clearance inlet, outlet, and the seal ring sizes are the determinant factors for clearance leakage flowrate, while the rotational speed and the radial size at clearance inlet are the major factors for clearance axial force. The rotational speed of rotating surfaces mainly affects the strength of rotating shear flow, while geometric sizes mainly affect the hydraulic loss of leakage flow. By assuming that the clearance region as several ring pipes, we obtained the simplified calculation formulas for estimating clearance leakage flowrate and clearance axial force. The flowrate can be expressed as a function of the water head difference across the clearance region, the rotational speed, and the sizes of clearance inlet, outlet and sealing ring, while the clearance axial force is a function of the inlet pressure and the square of both radius and rotational speed. The formula calculations agree with the numerical simulations well. This paper can provide a reference for runner clearance size design.

Plasma electrolytic oxidation (PEO) coatings were formed in silicate based electrolytes without and with the addition of sodium tungstate on AA 6063 aluminium alloy. Microstructure, composition and corrosion resistance of PEO coatings were investigated by scanning electron microscopy, X-ray diffraction and electrochemical impedance spectroscopy and potentiodynamic polarisation test respectively. The effects of additive sodium tungstate were examined. The results showed that the additive containing PEO coatings were of dense structure with additional phase (WO3) and of less cracks than the additive free PEO coating. In addition, additive containing coatings were of better corrosion resistance than the additive free PEO coating, which was confirmed by electrochemical impedance spectroscopy and potentiodynamic polarisation tests. Furthermore, long time immersion test revealed that the PEO coated alloy with the addition of 12 g L− 1 sodium tungstate maintained high impedance over 82 h in 3.5 wt-%NaCl, while t...

We experimentally study a vacuum-induced Autler-Townes doublet in a superconducting three-level artificial atom strongly coupled to a coplanar waveguide resonator and simultaneously to a transmission line. The Autler-Townes splitting is observed in the reflection spectrum from the three-level atom in a transition between the ground state and the second excited state when the transition between the two excited states is resonant with a resonator. By applying a driving field to the resonator, we observe a change in the regime of the Autler-Townes splitting from quantum (vacuum-induced) to classical (with many resonator photons). Furthermore, we show that the reflection of propagating microwaves in a transmission line could be controlled by different frequency single photons in a resonator., Comment: 5 pages, 3 figures+supplementary materials

Paraboloidal shells of revolution are commonly used in communication systems, precision opto-mechanical systems and aerospace structures. This study is to investigate the precision distributed control effectiveness of adaptive paraboloidal shells laminated with segmented actuator patches. Mathematical models of the paraboloidal shells laminated with distributed actuator layers subjected to mechanical, temperature, and control forces are presented first. Then, formulations of distributed actuating forces with their contributing micro-meridional/circumferential membrane and bending components are derived using an assumed mode shape function. Studies of actuator placements, actuator induced control forces, micro-contributing components, and normalized actuation authorities of paraboloidal shells are carried out. These forces and membrane/bending components basically exhibit distinct modal characteristics influenced by shell geometries and other design parameters. Analyses suggest that the membrane-contributed components dominate the overall control effect. Locations with larger normalized forces indicate the areas with high control efficiencies, i.e., larger induced actuation force per unit actuator area. With limited actuators, placing actuators at those locations would lead to the maximal control effects of paraboloidal shells.

The interaction mechanism between geogrid and mid-weak swelling rock in the Project of South-to-North Water Transfers Projects is investigated by pull-out tests conducted at the modified laminated shear test apparatus. Quasi-friction angle and quasi-cohesion force of the interface are obtained through the experiments of two types of geogrids at different vertical loadings. Furthermore, the distribution law of interface frictional resistance at the different location of geogrid is analyzed. Finally, distribution of additional shear stress in soil induced by IFR is preliminary investigated.

Expansive soil reinforced with synthetic fibers is a modified method developed in recent years, but experimental study results on its engineering behavior are rare at present. Polypropylence monofilament fibers are adopted to reinforce the expansive soil in Xinxiang, China, and the effect of moisture content, compaction degree, fiber content and sample size on the undrained strength behaviour of expansive soil reinforced with synthetic fibers are studied through unconfined compression strength test, and failure model of expansive soil reinforced with synthetic fibers is analyzed. Test results showed that unconfined strength of expansive soil modified with fibers is increased with a rise in compaction degree and fiber content, reduced with the increase of moisture content; under the same condition, strength resulting from small size sample is larger than that of large size sample; non-reinforced expansive soil assumes a brittle failure with an obvious shear failure plane; expansive soil reinforced with synthetic fibers shows a plastic failure with no obvious shear failure planes.

Shallow paraboloidal shells of revolution are common components for reflectors, mirrors, etc. This study is to investigate the micro-control actions and distributed control effectiveness of precision paraboloidal shell structures laminated with segmented actuator patches. Mathematical models and governing equations of the paraboloidal shells laminated with distributed actuator layers segmented into patches are presented first, followed by formulations of distributed control forces and micro-control actions including meridional/circumferential membrane and bending control components based on an assumed mode shape function and the Taylor series expansion. Distributed control forces, patch sizes, actuator locations, micro-control actions, and normalized control authorities of a shallow paraboloidal shell are then analyzed in a case study. Analysis indicates that 1) the control forces and membrane/bending components are mode and location dependent, 2) the meridional/circumferential membrane control actions dominate the overall control effect, 3) there are optimal actuator locations resulting in the maximal control effects at the minimal control cost for each natural mode. The analytical results provide generic design guidelines for actuator placement on precision shallow paraboloidal shell structures.

Paraboloidal shells of revolution are commonly used in communication systems, precision opto-mechanical systems and aerospace structures. This study is to investigate the precision distributed control effectiveness of paraboloidal shells laminated with segmented actuator patches. Mathematical models of the paraboloidal shells laminated with distributed actuator layers subjected to mechanical, temperature, and control forces are presented first, followed by formulations of distributed control forces with their contributing meridional/circumferential membrane and bending control components using an assumed mode shape function. Studies of actuator placements, control forces, contributing components, and normalized control authorities of paraboloidal shells are carried out. These forces and membrane/bending components basically exhibit distinct modal characteristics influenced by shell geometries and other design parameters. Analyses suggest that the membrane contributed components dominate the overall control effect. Locations with larger normalized forces indicate the areas with high control efficiencies, i.e., larger induced control force per unit actuator area. With limited actuators, placing actuators at those locations would lead to the maximal control effects.

Effective health monitoring and distributed control of advanced structures depends on accurate measurements of dynamic responses of elastic structures. Conventional sensors used for structural measurement are usually add-on “discrete” devices. Lightweight distributed thin-film piezoelectric neurons fully integrated (laminated or embedded) with structural components can serve as in-situ sensors monitoring structure’s dynamic state and health status. This study is to investigate modal voltages and detailed signal contributions of linear or nonlinear paraboloidal shells of revolution laminated with piezoelectric neurons. Signal generation of distributed neuron sensors laminated on paraboloidal shells is defined first, based on the open-voltage assumption and Maxwell’s principle. The neuron signal of a linear paraboloidal shell is composed of a linear membrane component and a linear bending component; the signal of a nonlinear paraboloidal shell governed by the von Karman geometric nonlinearity is composed of nonlinear and linear membrane components and a linear bending component. Signal components and distributed modal voltages of linear and nonlinear paraboloidal shells with various curvatures and thickness are investigated.

Smart structures and structronic (structure + electronic) systems are recognized as one of the essential technologies of the 21st century [1]. Conventional techniques used in modeling and analysis of structronic systems involves 1) theoretical analysis, 2) finite element analysis, and 3) laboratory experiments. This research is to investigate the fourth modeling and analysis technique based on the electrical analogy, i.e., using electronic circuits and components to model distributed structronic systems. A generic distributed structronic control system is shown in Figure 1.

Modeling distributed parameter systems (DPS) by electronic circuits and fabricating the complicated equivalent circuits to evaluate the system characteristics always poses many challenging research issues for years. Modeling and analysis of distributed sensing/control of smart structures and distributed structronic systems are even scarce. This paper is to present a technique to model distributed structronic systems with electronic circuits and to evaluate control behaviors with the fabricated equivalent circuits. Electrical analogies and analysis of distributed structronic systems is proposed and dynamics and control of beam/sensor/actuator systems are investigated. To determine the equivalent circuits and system parameters, higher order partial derivatives are simplified using the finite difference method; partial differential equations (PDE) are transformed to finite difference equations and further represented by electronic components and circuits. To provide better signal management and stability, active electronic circuit systems are designed and fabricated. Electric signals from the distributed system circuits (i.e., soft and hard) are compared with results obtained by classical theoretical and other (e.g., the finite element, and experimental) techniques.

Piezoelectric laminated distributed systems have broad applications in many new smart structures and structronic systems. As the shape control becomes an essential issue in practical applications, the nonlinear large deformation has to be considered, and thus, the geometrical nonlinearity has to be incorporated. Two electromechanical partial differential equations, one in the axial direction and the other in the transverse direction, are derived for the nonlinear PZT laminated beam model. The conventional approach is to neglect the axial oscillation and distributed sensing and control of the distributed laminated beam is evaluated, excluding the effect of axial oscillation. In this paper, influence of the axial displacement to the dynamics and distributed control effect is evaluated. Analysis results reveal that the axial displacement, indeed, has significant influence to the dynamic and distributed control responses of the nonlinear distributed PZT laminated beam structronics systems.

Recent development of smart structures and structronic systems has demonstrated the technology in many engineering applications. Active structural control of aircraft wings or helicopter blades (e.g., shapes, flaps, leading and/or trailing edges) can significantly enhance the aerodynamic efficiency and flight maneuverability of high-performance airplanes and helicopters. This paper in to evaluate the dual bending and torsion vibration control effects of an X-actuator configuration reconfigured from a parallel configuration. Finite element (FE) formation of a new FE using the layerwise constant shear angle theory is reviewed and the derived governing equations are discussed. Bending and torsion control effects of plates are studied using the FE method and also demonstrated via laboratory experiments. FE and experimental results both suggest the X-actuator is effective to both bending and torsion control of plates.

The materials of x-ray absorbers for x-ray mask have been changed from gold (Au) and tungsten-based alloys to tantalum (Ta) and Ta-based compounds in x-ray lithography (XRL). Different candidates of x-ray absorber, especially Ta-based (TaX) compounds, were sputtered and evaluated in this study. By incorporating silicon or germanium into tantalum, amorphous TaSi-based and TaGe-based compounds were formed and qualified as the absorber materials. Because the reproducibility of as-deposited stress by tuning the sputtering parameters is not so well for these compounds right after sputtering, we utilized the step annealing by RTA to control the stress such that within ± 20 MPa is obtainable. Furthermore, with N 2 plasma treatment in PECVD chamber the slope of stress with respect to annealing temperature is smaller and posses good stability after longtime exposure to the air. Finally, the etching properties of TaX compounds were compared with and without trilayer structure of oxide/absorber/oxide. And, 0.35 μ m patterns are etched successfully with vertical sidewall by Cl 2 etchant.

To characterize the binding of [125I]3 beta-(4-iodophenyl) tropane-2 beta-carboxylic acid isopropyl ester (RTI-121) to the dopamine transporter (DAT) under physiologically relevant conditions.[125I]RTI-121 was used to label the DAT on fresh rat striatum synaptosomal membranes in artificial cerebrospinal fluid (ACSF) at 37 degrees C.[125I]RTI-121 binding reached equilibrium within 3 min and remained at its plateau value for at least 9 min. The data from kinetic, saturation, and competition studies supported a one-site model for the binding of [125I]RTI-121 to the DAT. Various DAT blockers (oocaine, GBR12935, and BTCP) and substrates (dopamine and d-amphetamine) competitively inhibited the binding of [125I]RTI-121. Compared with NaPhos-KCl-NaCl assay buffer, ACSF containing Ca2+ and Mg2+ markedly increased the IC50 of DAT blockers for inhibiting [125I]RTI-121 binding with less effect on that of substrates. Various D2 receptor ligands (pergolide, quinirole, sulpiride, and l-stepholidine) had no direct effect on the binding of [125I]RTI-121.[125I]RTI-121 binding under physiologically relevant conditions fulfills the basic criteria for DAT binding assay.

Amniocytes isolated from two pregnancies at risk for fatty acid oxidation defects were incubated with stable isotopically labelled palmitate, in the presence of L-carnitine, to probe that pathway. The labelled acylcarnitines were then quantitated using tandem mass spectrometry. Amniocytes from a pregnancy at risk for medium-chain acyl-CoA dehydrogenase (MCAD) deficiency produced a characteristic acylcarnitine profile with increased levels of octanoylcarnitine and decanoylcarnitine, indicative of MCAD deficiency. DNA analysis confirmed that the fetus was homozygous for the MCAD A985G mutation. Acylcarnitine and DNA analysis of the infant's blood obtained post-partum confirmed MCAD deficiency. Amniocytes from a pregnancy at risk for an unspecified fat oxidation defect produced increased levels of long-chain acylcarnitines consistent with a deficiency in very-long-chain acyl-CoA dehydrogenase (VLCAD). Measurements of the enzymatic activity confirmed VLCAD deficiency in amniocytes. Acylcarnitine profiles of the infant's blood obtained post-partum in addition to enzyme activities measured in fibroblasts confirmed VLCAD deficiency. The successful prenatal diagnosis of VLCAD and MCAD deficiencies using in vitro probes of fatty acid oxidation in fibroblasts suggests that this approach can potentially recognize many mitochondrial fatty acid oxidation defects even if no prior diagnosis is determined in the family at risk.

Changes in CD44 transcripts have been previously found to be associated with metastasis in animal models. The purpose of this study was to investigate CD44V changes in four well established high grade human brain tumor cell lines, known to possess prominent invasive behavior. In Northern blot analysis, CD44S and CD44V were expressed strongly in three high-grade glioblastoma multiforme cell lines (GBM 8401, GBM 8909, GBM 8804) and one malignant meningioma cell line (IOMM). By RT-PCR and blot hybridization, three variant transcripts (650 bps, 850 bps, and 1,000 bps) were detected in GBM 8804 and two isoform transcripts (650 bps, 850 bps) were recognized in GBM 8401 and 8909. Further, in a malignant meningioma cell line (IOMM), only one weak isoform (650 bps) was detected. However, by Northern blot analysis, neither CD44S or CD44V could be expressed in normal brain and meningeal tissue. These results indicate that discrete CD44 mRNA splice variants are expressed in high grade glial cell tumors and malignant meningioma and suggest a possible role in the invasion of malignant brain tumors.

In spontaneously hypertensive rats (SHR), the heart microsomal Na+, K(+)-ATPase showed a reduced activity with a higher Ca2+ sensitivity and lower responsiveness to K+. After SHR were treated with tetrandrine (Tet, ig 30 mg.kg-1, qd x 30 d) or when the microsomes obtained from SHR hearts were incubated with various concentrations of Tet, the myocardial Na+,K(+)-ATPase showed a higher activity with a decreased Km for K+, or ATP and an increased Vmax for K+. The in vitro stimulatory effect of Tet on the enzyme was dependent on the Na+ concentration in medium and was not abolished by CaCl2 1 mmol.L-1 or ouabain 0.1 mmol.L-1. However, when given in vivo, Tet tended to reduce the tolerance of the enzyme to Ca2+ and failed to change the responsiveness of the enzyme to ouabain. In vitro, Tet had similar but weaker stimulatory effect on the Na+,K(+)-ATPase from Wistar Kyoto rats.

A mutation involving an A-to-G nucleotide replacement at position 985 of the medium-chain acyl-CoA dehydrogenase (MCAD) cDNA was found in homozygous form in 18 unrelated MCAD-deficient families and in heterozygous form in 4 families. By PCR amplification and sequencing of cDNA from a compound heterozygote, we have detected a new mutation in an MCAD-deficient patient in whom one MCAD allele produces mRNA that is missing 4 bp in the MCAD cDNA, while the other allele carries the A-to-G-985 mutation. The presence of this 4-bp deletion was confirmed in the patient's genomic DNA by dot-blot hybridization with allele-specific oligonucleotide probes and by restriction analysis of PCR products. A rapid screening test for this 4-bp deletion was developed, based on mismatched primer PCR amplification. The deletion created a new restrictive-enzyme site which yielded two DNA fragments. The 4-bp deletion was not found in the three remaining MCAD chromosomes not harboring the A-to-G-985 mutation, nor it was present in 20 chromosomes from 10 unrelated normal Caucasians. The PCR-based method for screening these two mutations can detect over 93% of all MCAD mutations.

In renovascular hypertensive rats (RVHR, two-kidney, one-clip model), the myocardial Na+, K(+)-ATPase showed a reduced activity. Though its sensitivities to K+ and ouabain (Oua) were not changed, the enzyme was less responsive to Na+ and ATP, and also much more susceptible to the inhibitory effect of Ca2+. Tetrandrine (Tet, ig 50 mg.kg-1, qd x 26 d) increased the myocardial Na+, K(+)-ATPase activity in RVHR. However, in vitro, Tet elevated moderately the enzyme activity in RVHR only at high concentrations (100-1,000 mumol.L-1), and failed to influence the enzyme activity in normotensive rats. In RVHR, treatment by Tet in vivo increased the degree of the Na+, K(+)-ATPase activation under suboptimal substrate (Na+, K+, or ATP) concentrations and antagonized the inhibitory effect of Ca2+ or Oua. Similar results were found when the enzyme preparation from RVHR was incubated with Tet 10 mumol.L-1 during ATPase analysis. On the contrary, the myocardial Mg(2+)-ATPase activity was higher in RVHR. Tet depressed this enzyme both in vivo and in vitro. These facts indicate that the increased myocardial Na+, K(+)-ATPase activity in RVHR is not only secondary to the calcium channel blocking or antihypertensive action of Tet but also due to its direct effects on the Na+, K(+)-ATPase and Mg(2+)-ATPase.

A number of variables were investigated in 46 men who had stopped taking gossypol for their predictive association with the degree and time of recovery of spermatogenesis. Thirty-nine (87%) of the men were azoospermic at cessation of gossypol treatment. In those with sperm present the geometric mean concentration and total sperm count were 8.3 X 10(6)/ml and 30.7 X 10(6), respectively. Twenty-eight men (61%) recovered to a defined threshold of spermatogenic function (sperm concentration greater than or equal to 20 X 10(6)/ml), with a median recovery time of 1.1 years. However, 18 men (39%) had not recovered to this degree of spermatogenic function after a median follow-up of 1.9 years and, of these, 10 (22%) remained azoospermic. The influence of individual baseline variables on the time to defined recovery was examined using Kaplan-Meier curves for groups and their joint effect by Cox's regression model. The failure of recovery was strongly associated with longer treatment, greater total dose of gossypol, smaller testicular volume, elevated FSH concentrations and, to a lesser extent, with greater body weight.

Genetic differences in aryl hydrocarbon hydroxylase (AHH) (flavoprotein-linked monoxygenase EC 1.14.14.1) activity in cultured lymphocytes have been linked with individual risk for certain environmentally caused cancers. Cytochrome P1-450 is the form of cytochrome P-450 most closely associated with AHH activity. In this study the chromosomal localization and the expression of human cytochrome P1-450 gene were determined in phytohemagglutinin-stimulated lymphocytes. In situ hybridization analysis provides assignment of the structural gene for human cytochrome P1-450 to chromosome 15q22-q24. Treatment of lymphocytes with benzanthracene increased the amount of mRNA hybridized to the cloned cytochrome P1-450 gene. The level of cytochrome P1-450 mRNA in these lymphocytes correlates well with the induced AHH activity indicating that non-cytochrome P1-450 enzymes contribute little to the individual differences in the level of AHH activity in the lymphocytes. Southern analyses of genomic DNA from individuals with high and low induced AHH activity demonstrated no detectable differences in the pattern or intensity of restriction fragments after treatment with benzanthracene from either individual. This finding together with the excellent correlation between the induced cytochrome P1-450 and AHH activity, suggests that transcriptional control rather than gene amplification or gross form of gene rearrangement accounts for cytochrome P1-450 induction in man. Measurements of cytochrome P1-450 mRNA content in cultured lymphocytes provide an alternative approach to the assay of AHH activity in assessing AHH phenotype and predicting different susceptibilities to deleterious environmental agents.

Type III glycogen storage disease is caused by a deficiency of glycogen debranching-enzyme activity. Many patients with this disease have both liver and muscle involvement, whereas others have only liver involvement without clinical or laboratory evidence of myopathy. To improve our understanding of the molecular basis of the disease, debranching enzyme was purified 238-fold from porcine skeletal muscle. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis the purified enzyme gave a single band with a relative molecular weight of 160,000 that migrated to the same position as purified rabbit-muscle debranching enzyme. Antiserum against porcine debranching enzyme was prepared in rabbit. The antiserum reacted against porcine debranching enzyme with a single precipitin line and demonstrated a reaction having complete identity to those of both the enzyme present in crude muscle and the enzyme present in liver extracts. Incubation of antiserum with purified porcine debranching enzyme inhibited almost all enzyme activity, whereas such treatment with preimmune serum had little effect. The antiserum also inhibited debranching-enzyme activity in crude liver extracts from both pigs and humans to the same extent as was observed in muscle. Immunoblot analysis probed with anti-porcine-muscle debranching-enzyme antiserum showed that the antiserum can detect debranching enzyme in both human muscle and human liver. The bands detected in human samples by the antiserum were the same size as the one detected in porcine muscle. Five patients with Type III and six patients with other types of glycogen storage disease were subjected to immunoblot analysis. Although anti-porcine antiserum detected specific bands in all liver and muscle samples from patients with other types of glycogen storage disease (Types I, II, and IX), the antiserum detected no cross-reactive material in any of the liver or muscle samples from patients with Type III glycogen storage disease. These data indicate (1) immunochemical similarity of debranching enzyme in liver and muscle and (2) that deficiency of debranching-enzyme activity in Type III glycogen storage disease is due to absence of debrancher protein in the patients that we studied.