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This study investigates the H∞ control problem for a class of continuous-time Markovian jump singular systems. The authors' attention is focused on the design of state and static output feedback controllers which ensure that the closed-loop system is regular, impulse-free and stochastically stable, and satisfies a prescribed H∞ performance level. To investigate the problem of H∞ performance analysis for the system under consideration, a bounded real lemma (BRL) is provided in terms of linear matrix inequality (LMI) containing equality constraints, which may not be a problem from the theoretical point of view, but may cause great big trouble in checking the conditions numerically. To solve this problem, a new version of BRL is also provided in terms of strict LMIs. Based on this, two approaches are established to solve the problem of state feedback H∞ control, and then, the problem of static output feedback H∞ control is solved, which can also be used for solving the dynamic output feedback control problems. Finally, two numerical examples are given to illustrate the effectiveness of the obtained theoretical results. [ABSTRACT FROM AUTHOR]

The dual tunable band-notched characteristics are achieved on a novel printed monopole antenna operating over 2.6–11 GHz bandwidth with VSWR < 2, to minimize potential interference with the bands of 3.3–3.7 GHz for WIMAX and 5.15–5.825 GHz for WLAN. Two notched-bands are created by the two slots etched in its radiation patch and ground plane, respectively. Their central frequencies can be easily tuned individually by placing a capacitor and an inductor on each of the slots. The antenna has been simulated, measured and discussed. The measured results agree reasonably with the simulated ones, showing good impedance matching, stable gain, small group delay, and near omnidirectional patterns in the H-plane across the operation band. The designed antenna has the miniature dimension of 18 mm × 18 mm × 0.8 mm. [ABSTRACT FROM AUTHOR]

β-Galactosidase catalyzes the hydrolysis of β-galactosides into monosaccharides and is widely used in dairy processing. This study reports the extracellular secretion of a cytoplasmic thermostable β-galactosidase from Geobacillus stearothermophilus IAM11001 in Bacillus subtilis. This enzyme has potential applications in the dairy industry. It was not secreted in B. subtilis by mediation of 3 general secretory signal peptides, but was secreted extracellularly when it was fused to a twin-arginine signal peptide of B. subtilis phosphodiesterase. Defined and rich culture media were used for recombinant enzyme production, and the extracellular target enzymatic activity reached about 44% of the total enzymatic activity synthesized at 18h of cultivation in Luria-Bertani medium. As a control of secretion, when the signal peptide coding sequence was absent from the N terminus of the target gene bgaB, the extracellular target enzymatic activity obtained under the same condition of cultivation accounted for less than 7% of the total enzymatic activity synthesized. Results also showed that coexpression of the B. subtilis proteins TatAd and TatCd was indispensable for the secretion of the target enzyme. [ABSTRACT FROM AUTHOR]

Contents The expression and concentration of follistatin and activin change during oestrous cycle suggesting their involvement in the regulation of follicular development. The aim of this study was to determine the level, source and potential role of follistatin in the sheep ovary. Follistatin in ovarian venous blood, measured by radioimmunoassay, remained at its low level from follicular phase (day −1 and 0) to mid-luteal phase (days 11–13) phase but were significantly elevated during the late luteal phase (days 14 and 15) when corpora lutea underwent regression. Western blot analyses of follicular fluid at day 15 of the cycle showed two strong bands at 42 and 45 kDa and weakly stained bands at 39 and 31 kDa. At day 0, these bands became weaker and the 39 kDa band became undetectable. However, there were no differences in follistatin concentrations between ovaries with and without functional corpus luteum (CL) during the whole luteal phase. In addition, although the ovaries of Booroola ewes normally contain more corpora lutea than those of normal merino ewes, follistatin concentrations in both jugular and ovarian venous blood were similar in Booroola and normal merino ewes. It is concluded that the secretion of follistatin from the ovary is not related to the formation of CL or high ovulation rate of Booroola ewes. The elevation in follistatin concentration in follicular fluid and ovarian blood during late luteal phase may indicate a dual role of follistatin in the luteolysis of existing CL and development of new follicle cohort. [ABSTRACT FROM AUTHOR]

We propose an optical protocol for generating four-photon polarization-entangled decoherence-free states between two arbitrary parties under control of a number of controllers in terms of optical elements. We show that the protocol can be successfully realized with a certain probability. [ABSTRACT FROM AUTHOR]

The article presents a study on the parallel monitoring of Radon 222 Rn at the top of Schauinsland mountain and the forests in South-West Germany which were conducted from November 2007 to April 2008. It states that the Radon was measured through two-filter detector and one-filter detector. It says that there was 87% concentration without precipitation and 74% with precipitation of Rn in the two major wind sectors that was covered by the forest.

The tribological performance of PA6 and carbon fiber reinforced polyamide 6 (CF/PA6) under dry sliding condition was examined. Different contents of carbon fibers were employed as reinforcement. All filled and unfilled polyamide 6 composites were tested against CGr15 ball and representative testing was performed. The effects of carbon fiber content on tribological properties of the composites were investigated. The worn surface morphologies of neat PA6 and its composites were examined by scanning electron microscopy and the wear mechanisms were discussed. Moreover, all filled polyamide 6 have superior tribological characteristics to unfilled polyamides 6. The optimum wear reduction was obtained when the content of carbon fiber is 20 vol%. [ABSTRACT FROM AUTHOR]

Robust sliding mode control is designed for a class of uncertain systems with time delay in discrete time. The uncertainties include both mismatched parametric uncertainties in the state model and the matched external disturbance. After deriving sufficient conditions for the existence of linear sliding surfaces based on linear matrix inequality (LMI), robust reaching motion control is presented. A simulation study shows the effectiveness of the control scheme. [ABSTRACT FROM AUTHOR]

Objective: The aims of this study were (a) to investigate the neuropathological damage in brain regions and changes of corticosteroid concentrations related to chronic alcohol administration, (b) to see what effect fluoxetine (Prozac) has on the neuropathological damage and corticosteroid levels, and (c) to evaluate the potential association between neuropathological damage and changes of corticosteroid levels.Method: Rats were randomly divided into alcohol and control groups, with the former given ethanol intraperitoneally for 8 weeks; corticosterone levels were measured in both groups. Thereafter, fluoxetine hydrochloride or saline was injected into the animals. The rats were sacrificed and the number of neurons in five regions of the cerebral cortex was determined.Results: The numbers of neurons in the frontal cortex, parietal cortex, and CA3 regions of the hippocampus of the alcoholic group treated with saline were significantly reduced compared with the control group treated with saline. The number of neurons observed in CA3 regions of the hippocampal cortex of the alcoholic group treated with fluoxetine was significantly increased compared with the alcoholic group treated with saline. Corticosteroid levels of the alcoholic group treated with saline were significantly increased compared with the control group. Corticosteroid levels of the alcoholic group treated with fluoxetine were obviously reduced compared with the alcoholic group treated with saline. The number of neurons in the CA3 regions of the hippocampus was adversely associated with corticosteroid levels.Conclusions: Chronic alcohol administration induced selective loss of neurons in different brain regions and increased corticosteroid concentrations. Fluoxetine may have alleviated neuronal loss in the hippocampus and attenuated hypercortisolemia related to alcohol. [ABSTRACT FROM AUTHOR]

Abstract: Precipitation variability and shrub encroachment in response to global environmental change are likely to affect both richness and aboveground net primary production (ANPP) of annual plants in arid and semi-arid ecosystems in the northern Chihuahuan Desert, especially given the grazing history and desertification potential of this aridland region. Using a nine-year dataset (1999–2007), we examined the spatial and temporal variation in annual plant communities in grass- and shrub-dominated vegetation, and evaluated the relationships between species richness and ANPP with seasonal and annual precipitation and soil moisture. We found that species richness and ANPP varied among seasons and between years in both grass- and shrub-dominated areas. Cryptantha crassisepala, Plantago patagonica, and Phacelia integrifolia were the most common species found in both communities in both seasons, and Chamaesyce serrula, C. serpyllifolia, and Kallstroemia parviflora were more common in summer only. We found that species richness in summer was significantly correlated with summer precipitation and summer soil moisture in both communities, but summer ANPP was significantly correlated with summer precipitation and soil moisture only in shrubland. However, richness and ANPP of winter annuals were significantly correlated with winter precipitation and winter soil moisture in shrubland and grassland. Our results demonstrate that temporal variation in rainfall can be as important as annual total amounts for plant performance, and that response to temporal dynamics varies among species but not between grass- and shrub-dominated communities. We conclude that desert annuals provide a highly dynamic system for understanding the processes that influence plant species composition and abundance, and that desert annual systems will likely be highly impacted by shrub encroachment along with increases in precipitation variability as a consequence of anthropogenic climate change. [Copyright &y& Elsevier]

Abstract: Correlations and a model are developed to predict the time-varying performance of folded-louvered-fin, microchannel heat exchangers. The model utilizes the correlations developed from the experimental data and incorporates a sub-model for frost properties. The model successfully predicts the heat transfer performance of the heat exchangers studied, but its ability to predict the pressure-drop behavior needs further improvement. The model can be used to evaluate geometry effects on the frosting behavior of the louvered-fin, microchannel heat exchangers, and can be easily generalized to other applications with simultaneous heat and mass transfer. [Copyright &y& Elsevier]

The tribological performance of PA6 and carbon fiber-reinforced polyamide 6 (CF/PA6) under dry sliding condition was examined. Different contents of carbon fibers were employed as reinforcement. All filled and unfilled polyamide 6 composites were tested against CGr15 ball and representative testing was performed. The effects of carbon fiber content on tribological properties of the composites were investigated. All filled polyamide 6 has superior tribological characteristics to unfilled polyamide 6. The optimum wear reduction is obtained when the content of carbon fiber is 20 vol% [ABSTRACT FROM AUTHOR]

In this study, the problem of designing regular robust l2–l∞ filter for a class of linear singular discrete-time systems with norm-bounded uncertainties is investigated. A class of regular linear filters is fully analysed, then necessary and sufficient conditions of robust admissibility are established. Guaranteed l2–l∞ performance of the filtered system is provided and expressed in terms of the solution of strict linear matrix inequalities (LMIs). The cases of full- and zeroth-order realisable filter are derived as limiting cases of design. Numerical examples are worked out to illustrate the theoretical development. [ABSTRACT FROM AUTHOR]

We propose a new linear optical protocol for remote state preparation (RSP) between two parties under control of a number of controllers in terms of optical elements. The proposed setup involves simple linear optical elements, a N-photon polarization entangled state, and photon de tectors, witch have been widely used in experiment. The realization of this protocol is appealing due to the fact that quantum state of light is robust against the decoherence and photons are ideal carriers for transmitting quantum information over long distances. [ABSTRACT FROM AUTHOR]

A double Tavis-Cummings model (DTCM) is developed to simulate the entanglement dynamics of realistic quantum information processing where two entangled atom-pairs AB and CD are distributed in such a way that atoms AC are embedded in a cavity a while BD are located in another remote cavity b. The evolutions of different types of initially shared entanglement of atoms are studied under various initial states of cavity fields. The results obtained in the DTCM are compared with that obtained in the double Jaynes-Cummings model (DJCM) [M. Yönaç, T. Yu, J.H. Eberly, J. Phys. B 40, S45 (2007)] and an interaction strength theory is proposed to explain the parameter domain in which the so-called entanglement sudden death occurs for both the DTCM and DJCM. [ABSTRACT FROM AUTHOR]

Abstract: The mechanism underlying phencyclidine (PCP)-induced apoptosis in perinatal rats and the development of schizophrenia-like behaviors is incompletely understood. We used antagonists for N-methyl-d-aspartate (NMDA) receptor subunit NR2A- and NR2B-containing NMDA receptor to test the hypothesis that the behavioral and apoptotic effects of PCP are mediated by blockade of NR1/NR2A-containing receptors, rather than NR1/NR2B-containing receptors. Sprague-Dawley rats were treated on PN7, PN9, and PN11 with PCP (10 mg/kg), PEAQX (NR2A-preferring antagonist; 10, 20, or 40 mg/kg), or ifenprodil (selective NR2B antagonist; 1, 5, or 10 mg/kg) and sacrificed for measurement of caspase-3 activity (an index of apoptosis) or allowed to age and tested for locomotor sensitization to PCP challenge on PN28-PN35. PCP or PEAQX on PN7, PN9, and PN11 markedly elevated caspase-3 activity in the cortex; ifenprodil showed no effect. Striatal apoptosis was evident only after subchronic treatment with a high dose of PEAQX (20 mg/kg). Animals treated with PCP or PEAQX on PN7, PN9, and PN11 showed a sensitized locomotor response to PCP challenge on PN28-PN35. Ifenprodil treatment had no effect on either measure. Therefore, PCP blockade of cortical NR1/NR2A, rather than NR1/NR2B, appears to be responsible for PCP-induced apoptosis and the development of long-lasting behavioral deficits. [Copyright &y& Elsevier]

Blending Polytetrafluorothylene (PTFE) to PA6 with and without maleic anhydride grafted Polytetrafluorothylene (PTFE-g-MA) was produced in a corotating twin screw extruder. The effect of PTFE-g-MA on the tensile properties and tribological properties of PTFE/PA6 polymer blends is studied. Results show that the presence of PTFE-g-PA6 in the PTFE continuous phase improves the interfacial adhesion, as a result of the creation of an interphase that was formed by the interaction between the formed PTFE-g-PA6 copolymer in situ and both phases. Compared with the PTFE/PA6 without PTFE-g-MA, the PTFE/PA6 with PTFE-g-MA had the lowest friction coefficient and specific wear rate under given applied load and reciprocating sliding frequency. [ABSTRACT FROM AUTHOR]

Loss of capsaicin and dihydrocapsaicin is a problem in the preparation and storage of dehydrated peppers. In this study, the effects of heating (100 °C to 260 °C, 15 min) and storage conditions (vacuum vs. non-vacuum package, room temperature vs. refrigeration temperature) on the content of capsaicin and dihydrocapsaicin in chili pepper powder were studied with pungent components assayed by HPLC. Heating between 100 °C and 190 °C for 15 min did not seriously affect the content of capsaicinoids (<10% reduction). However, at temperatures greater than 190 °C, capsaicin and dihydrocapsaicin degraded rapidly. Low-temperature storage improved retention of capsaicinoids, and vacuum packaging provided little if any extra benefit. Capsaicin and dihydrocapsaicin had very similar stability and showed similar reduction rates during heating and storage, which indicates that the C=C bond in capsaicin is relatively stable and does not account for its decomposition during heating and storage. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the problems of robust delay-dependent ℒ2 gain analysis and feedback control synthesis for a class of nominally-linear switched discrete-time systems with time-varying delays, bounded nonlinearities and real convex bounded parametric uncertainties in all system matrices under arbitrary switching sequences. We develop new criteria for such class of switched systems based on the constructive use of an appropriate switched Lyapunov-Krasovskii functional coupled with Finsler’s Lemma and a free-weighting parameter matrix. We establish an LMI characterization of delay-dependent conditions under which the nonlinear switched delay system is robustly asymptotically stable with an ℒ2-gain smaller than a prescribed constant level. Switched feedback schemes, based on state measurements, output measurements or by using dynamic output feedback, are designed to guarantee that the corresponding switched closed-loop system enjoys the delay-dependent asymptotic stability with an ℒ2 gain smaller than a prescribed constant level. All the developed results are expressed in terms of convex optimization over LMIs and tested on representative examples. [ABSTRACT FROM AUTHOR]

This study is concerned with the stochastic stability analysis of networked control systems with random network delay. A new control scheme termed networked predictive control is proposed. This scheme mainly consists of the control prediction generator and network-delay compensator. The control prediction generator provides a set of future control predictions to make the closed-loop system achieve the desired control performance and the network-delay compensator removes the effects of the network transmission delay and data dropout. The stochastic stability criteria of the closed-loop networked predictive control systems are derived. A numerical example and a practical experiment are given to show the potential of the proposed techniques. [ABSTRACT FROM AUTHOR]

Helical Dirac fermions—charge carriers that behave as massless relativistic particles with an intrinsic angular momentum (spin) locked to its translational momentum—are proposed to be the key to realizing fundamentally new phenomena in condensed matter physics. Prominent examples include the anomalous quantization of magneto-electric coupling, half-fermion states that are their own antiparticle, and charge fractionalization in a Bose–Einstein condensate, all of which are not possible with conventional Dirac fermions of the graphene variety. Helical Dirac fermions have so far remained elusive owing to the lack of necessary spin-sensitive measurements and because such fermions are forbidden to exist in conventional materials harbouring relativistic electrons, such as graphene or bismuth. It has recently been proposed that helical Dirac fermions may exist at the edges of certain types of topologically ordered insulators—materials with a bulk insulating gap of spin–orbit origin and surface states protected against scattering by time-reversal symmetry—and that their peculiar properties may be accessed provided the insulator is tuned into the so-called topological transport regime. However, helical Dirac fermions have not been observed in existing topological insulators. Here we report the realization and characterization of a tunable topological insulator in a bismuth-based class of material by combining spin-imaging and momentum-resolved spectroscopies, bulk charge compensation, Hall transport measurements and surface quantum control. Our results reveal a spin-momentum locked Dirac cone carrying a non-trivial Berry’s phase that is nearly 100 per cent spin-polarized, which exhibits a tunable topological fermion density in the vicinity of the Kramers point and can be driven to the long-sought topological spin transport regime. The observed topological nodal state is shown to be protected even up to 300 K. Our demonstration of room-temperature topological order and non-trivial spin-texture in stoichiometric Bi2Se3.Mx (Mx indicates surface doping or gating control) paves the way for future graphene-like studies of topological insulators, and applications of the observed spin-polarized edge channels in spintronic and computing technologies possibly at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: Glutamate-induced neural cell death is mediated by excitotoxicity and oxidative stress. Treatment of glutamate toxicity with estrogen and its related compounds for neuroprotection remains controversial. In this study, we examined the effects of selective estrogen receptor (ER) ligands on glutamate toxicity and found that R,R-tetrahydrochrysene (R,R-THC), an antagonist of ERβ and agonist of ERα, has neuroprotective effects against glutamate-induced death in primary rat cortical cells and mouse N29/4 hypothalamic cells. The protective effect of R,R-THC was dose-dependent and was maintained even when added several hours after the initial glutamate exposure. R,R-THC blocked glutamate-induced depletion of intracellular glutathione, increased superoxide dismutase activity, and protected cells from hydrogen peroxide–induced death. R,R-THC also prevented glutamate-induced nuclear translocation of apoptotic inducing factor and release of mitochondrial cytochrome c. The protective effect of R,R-THC was blocked by methyl-piperidino-pyrazole (MPP; an ERα antagonist) in glutamate-treated cortical cells, and pretreatment with MK-801 (an NMDA receptor antagonist) but not CNQX (an AMPA/kainate receptor antagonist) increased cell survival. On the other hand, MPP did not block the protective effect of R,R-THC in glutamate-treated N29/4 cells, and neither MK-801 nor CNQX conferred protection. Activation of ERα and/or ERβ with 17β-estradiol (E2), propyl-pyrazole-triol or diarylpropionitrile did not provide effective neuroprotection, and pretreatment with ICI 182,780 did not inhibit the protective effect of R,R-THC in either type of cell. These results suggest that the use of ER agonists (including E2) has limited beneficial effects when both excitotoxicity and oxidative stress occur. In contrast to agonists of ERs, R,R-THC, which possesses anti-excitotoxic and antioxidant actions via ER-dependent and -independent pathways, provides significant neuroprotection. [Copyright &y& Elsevier]

Adipose-derived stem cells (ADSCs) have been shown to induce wound-healing effects. Because inflammation near the wound area induces oxygen deficiency, it is interesting to elucidate the effect of hypoxia on the function of ADSCs. In this work, we asked: (1) does hypoxia alter the wound-healing function of ADSCs? and (2) what are the major factors responsible for the alteration in the wound-healing function? Effect of hypoxia on the proliferation of ADSCs was first examined that hypoxia (2% O2) enhanced the proliferation of ADSCs in either the presence of serum or in the absence of serum. The conditioned medium of ADSCs harvested under hypoxia (hypoCM) significantly promoted collagen synthesis and the migration of human dermal fibroblasts, compared with that in normoxia (norCM). In the animal studies, hypoCM significantly reduced the wound area compared with norCM. Furthermore, mRNA and protein measurements showed that hypoxia up-regulated growth factors such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). Inhibition of VEGF and bFGF using neutralizing antibodies reversed the migration of the wounded human dermal fibroblasts and the healing of wounds in animal experiment. Collectively, these results suggest that hypoxia increases the proliferation of ADSCs and enhances the wound-healing function of ADSCs, at least partly, by up-regulating the secretion of VEGF and bFGF. [ABSTRACT FROM AUTHOR]

The conception of an area's carrying capacity has proven to be a useful concept at various scales ranging from populations to the entire biosphere, and it appears to be a suitable definition for any level. For soil water-carrying capacity for vegetation (SWCCV), the concept evokes density-dependence research in arid and semi-arid regions. The term is increasingly being used among ecological disciplines but remains vague and elusive. We propose the following definition: the SWCCV is 'the maximum biomass of a given type of vegetation, under specific climatic conditions, soil texture, and management regime, that a given arid or semi-arid area can sustain without diminishing the capacity of soil water to support future generations. Models for assessing the SWCCV of an area of interest, though preliminary, can be classified into three types according to their construction: empirical, conceptual, and process models. Neither the empirical model nor the conceptual model can account for the dynamic interactions between soil water and vegetation for heterogeneous environmental matrices in arid and semi-arid regions. The physically based process model would enable us to effectively analyse and simulate the components of the SWCCV. While water cycle and photosynthesis are not properly integrated in such quantitative models, the effects of water stress on transpiration, carbon-assimilation rates, and its feedback into the water cycle are not generally represented. From our point of view, hydrological and biogeochemical cycles need to be modelled in detail and simultaneously, while considering feedbacks between vegetation growth and soil hydrological processes. [ABSTRACT FROM AUTHOR]

This study is concerned with the generalised ℋ2 and the ℋ∞ static control problems for discrete-time fuzzy systems with time-varying norm-bounded parametric uncertainties. Based on the solutions to certain linear matrix inequalities LMIs, static output feedback controllers are designed, which can ensure the asymptotic stability and the generalised ℋ2 and ℋ∞ performance level, respectively. Differenting from the existing results, the design conditions in this study are derived in terms of LMIs directly, and the local output matrices are allowed to be different. Three illustrative examples are provided to demonstrate the effectiveness and the reduced conservatism of the proposed methods. [ABSTRACT FROM AUTHOR]

Recent experiments and theories have suggested that strong spin–orbit coupling effects in certain band insulators can give rise to a new phase of quantum matter, the so-called topological insulator, which can show macroscopic quantum-entanglement effects. Such systems feature two-dimensional surface states whose electrodynamic properties are described not by the conventional Maxwell equations but rather by an attached axion field, originally proposed to describe interacting quarks. It has been proposed that a topological insulator with a single Dirac cone interfaced with a superconductor can form the most elementary unit for performing fault-tolerant quantum computation. Here we present an angle-resolved photoemission spectroscopy study that reveals the first observation of such a topological state of matter featuring a single surface Dirac cone realized in the naturally occurring Bi2Se3 class of materials. Our results, supported by our theoretical calculations, demonstrate that undoped Bi2Se3 can serve as the parent matrix compound for the long-sought topological device where in-plane carrier transport would have a purely quantum topological origin. Our study further suggests that the undoped compound reached via n-to-p doping should show topological transport phenomena even at room temperature. [ABSTRACT FROM AUTHOR]

We propose a scheme to generate a maximally four-dimensional entangled state of two six-level atoms in two remote cavities. By choosing suitable intensities and detunings of fields, atomic spontaneous radiation and photon leakage out of cavity and fibre are efficiently suppressed. Thus, the intended state can be generated with high fidelity in the presence of decoherence. We extend the scheme to generate an N-atom four-dimensional entangled state. [ABSTRACT FROM AUTHOR]

A topologically ordered material is characterized by a rare quantum organization of electrons that evades the conventional spontaneously broken symmetry-based classification of condensed matter. Exotic spin-transport phenomena, such as the dissipationless quantum spin Hall effect, have been speculated to originate from a topological order whose identification requires a spin-sensitive measurement, which does not exist to this date in any system. Using Mott polarimetry, we probed the spin degrees of freedom and demonstrated that topological quantum numbers are completely determined from spin texture-imaging measurements. Applying this method to Sb and Bi1-xSbx, we identified the origin of its topological order and unusual chiral properties. These results taken together constitute the first observation of surface electrons collectively carrying a topological quantum Berry's phase and definite spin chirality, which are the key electronic properties component for realizing topological quantum computing bits with intrinsic spin Hall-like topological phenomena. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel printed wideband monopole antenna with simple structure and compact size. The proposed antenna can provide two separate impedance bandwidths of 1.55 GHz about 48.8% (from 2.4 to 3.95 GHz) and 1.275 GHz about 22.4% (from 5.05 to 6.325 GHz), making it easily cover the required bandwidths for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) operations. Also, good antenna performances such as radiation patterns and antenna gains over the operating bands have been observed. Details of the proposed antenna design and experimental results are presented and discussed. [ABSTRACT FROM AUTHOR]

We have built a complete Raman detection system for multi-trace-gas diagnosis, which is suitable for analyzing the dissolved gases in electric power system. In the system, a high-sensitivity CCD device connected to a spectrometer is used as the detection unit of the Raman system. A near-confocal cavity is used for improving the detection sensitivity of the system. In the effective spectral range of about 570–710 nm, Raman spectra of eight typical gases are achieved by using this Raman system. The detection limits for different gases have been obtained: 126 ppm for CO2, 21 ppm for CH4, 63 ppm for C2H4, 42 ppm for C2H2, 96.6 ppm for H2. The detectability of the system satisfies the requirements of gas diagnosis in power transformer. [ABSTRACT FROM AUTHOR]

We propose a protocol to generate the cluster states of four A-type three-level atoms trapped in distant cavities by using the interference of polarized photons. The protocol uses the effects of the quantum statistics of indistinguishable photons emitted by the atoms inside optical cavities. This makes the protocol more realizable in experiments. [ABSTRACT FROM AUTHOR]

Abstract: Fifteen articular cartilage-bone specimens from one canine humeral joint were compressed in the strain range of 0–50%. The deformation of the extracellular matrices in cartilage was preserved and the same tissue sections were studied using polarized light microscopy (PLM) and Fourier-transform infrared imaging (FTIRI). The PLM results show that the most significant changes in the apparent zone thickness due to ‘reorganization’ of the collagen fibrils based on the birefringence occur between 0% and 20% strain values, where the increase in the superficial zone and decrease in the radial zone thicknesses are approximately linear with the applied strain. The FTIRI anisotropy results show that the two amide components with bond direction perpendicular to the external compression retain anisotropy (amide II in the superficial zone and amide I in the radial zone). In contrast, the measured anisotropy from the two amide components with bond direction parallel to the external compression changes their anisotropy significantly (amide I in the superficial zone and amide II in the radial zone). Statistical analysis shows that there is an excellent correlation (r =0.98) between the relative depth of the minimum retardance in PLM and the relative depth of the amide II anisotropic cross-over. The changes in amide anisotropies in different histological zones are explained by the strain-dependent tipping angle of the amide bonds. These depth-dependent adaptations to static loading in cartilage’s morphological structure and chemical distribution could be useful in the future studies of the early diseased cartilage. [Copyright &y& Elsevier]

This paper deals with the class of linear discrete-time systems with random abrupt changes also known as class of Markovian jump singular systems. The problems of stochastic stability and the stochastic stabilisation (using state-feedback control and static output feedback control) are tackled. Conditions in the LMI setting to design the appropriate gains of the controllers are developed. It is shown that all the addressed problems can be solved if the corresponding developed linear matrix inequalities (LMIs) are feasible. Numerical examples are employed to show the usefulness of the proposed results. [ABSTRACT FROM AUTHOR]

Ammonium polyphosphate (APP) and pentaerythritol (PER) were selected to form intumescent flame-retardant (IFR) and halogen-free flame-retardant ABS/IFR/zeolite composites were prepared by melt blending. The influences of zeolite 4A, 13X on thermal behavior of mass loss, flame-retardant performance, microstructure, mechanical properties, and processability of composites were investigated. The results showed that zeolite 4A with a lower Si/Al ratio, stronger surface polarity, and lower loading not only had a better synergistic effect with IFR, which promoted the catalytic esterification of IFR, stabilized the charred residue, and made ABS/IFR composites possess higher flame-retardant performance, but also was beneficial to improving the mechanical properties and processability of composites. When the content of zeolite 4A was 1 wt%, ABS/IFR composites had better comprehensive properties. Its limiting oxygen index (LOI) value, impact strength, tensile strength, flexural strength, modulus, and melt index were 32.6%, 3.4 KJ/m2, 39 MPa, 38.7 MPa, 1337 MPa, and 24.5 g/10 min, respectively. [ABSTRACT FROM AUTHOR]

The problem of robust state feedback control using delta operator approach for a class of linear fractional uncertain systems with time-varying delays is investigated. Based on Lyapunov–Krasovskii functional in delta domain, a new delay-dependent state feedback controller is presented in terms of linear matrix inequalities. The sampling-period T is an explicit parameter, and thus it is easy to observe and analyse the effect of the state feedback controller with different sampling periods. The proposed method can unify some previous related continuous and discrete systems into the framework of delta operator systems. Numerical examples are given to illustrate the effectiveness of the developed techniques. [ABSTRACT FROM AUTHOR]

Although various genetic factors have been demonstrated in human male infertility, many genetic causes involving gene variants for the idiopathic male infertility have not yet been elucidated. P53 gene is involved in the meiosis of the male rat and mice, which suggested that p53 plays a critical role in spermatogenesis. To examine whether the codon72 polymorphism and IVS7 + 72C>T polymorphism of the human p53 gene are associated with spermatogenetic failure in Han-Chinese population. A case–control study was conducted with 198 idiopathic infertile patients with nonobstructive azoospermia or severe oligozoospermia and 233 fertile controls. We genotyped the two polymorphisms, codon72 and IVS7 + 72C>T, using polymerase chain reaction-restriction fragment length polymorphism assay. The polymorphisms were identified in both infertile patients and fertile controls. The allele and genotype frequencies of the two polymorphisms were not significantly different between the patients and controls. Further analysis showed that there was no statistically significant difference in the haplotype distributions between the patients and controls. The results of this study suggest that the codon72 and IVS7 + 72C>T polymorphisms of the p53 gene are unlikely to contribute to the pathogenesis of idiopathic male infertility with spermatogenetic failure. [ABSTRACT FROM AUTHOR]

18599 Hong, a good maize ( Zea mays) inbred line as well as good transformation acceptor with high regeneration capacity, was used for isolating embryonic callus regeneration genes. Subtractive library was constructed by suppression subtractive hybridization and screened by reverse Northern hybridization. The clones of no. 27 was randomly picked to sequence. NCBI blastx results showed the similarity to elongation factor 1γ in rice. [ABSTRACT FROM AUTHOR]

Calibration of land surface models improves simulations of surface water and energy fluxes and provides important information for water resources management. However, most calibration studies focus on local sites and/or small catchments because of computational limitations, lack of atmospheric forcing data, and lack of observed water and energy fluxes. Even though a well-established streamflow gauge network exists, its data are not well suited to the calibration of land surface models in cold regions because of large systematic precipitation biases. This study provides a newly developed method to adjust systematic precipitation biases arising from gauge undercatch (e.g., wind blowing, wetting loss, and evaporation loss). The new method estimates model parameter and precipitation errors simultaneously through the use of observed annual streamflow in the northeastern United States. The results show that this method improves streamflow simulations and gives a reasonable estimate for systematic precipitation bias. In addition, the impacts of model parameter errors on the calibration of the Land Dynamics (LaD) model and on the estimation of systematic precipitation biases are investigated in the northeastern United States. [ABSTRACT FROM AUTHOR]

The complexation of plutonium(IV) with sulfate at variable temperatures has been investigated by solvent extraction method. A NaBrO3 solution was used as holding oxidant to maintain the plutonium(IV) oxidation state throughout the experiments. The distribution ratio of Pu(IV) between the organic and aqueous phases was found to decrease as the concentrations of sulfate were increased. Stability constants of the 1:1 and 1:2 Pu(IV)-HSO4 − complexes, dominant in the aqueous phase, were calculated from the effect of [HSO4 −] on the distribution ratio. The enthalpy and entropy of complexation were calculated from the stability constants at different temperatures using the Van’t Hoff equation. [ABSTRACT FROM AUTHOR]

A nontrivial protocol for teleporting an unknown N-qubit W-like state is proposed. The consumed resource is only ( N-1) shared ebits and 2( N-1) bits of classical communication, while the technique involves only controlled-NOT gates and single-qubit measurements/operations. The rule for reconstruction of the desired state at the receiving station is worked out explicitly in the most general case of an arbitrary N ≥ 3. The protocol is within the reach of present technologies. [ABSTRACT FROM AUTHOR]

Quantitative ultrasound (QUS) has been used to assess non-invasively bone quality, in which ultrasound velocity (UV) is a primary acoustic property. While UV calculation requires the tissue thickness in the ultrasound path, a bone surface topology mapping (STM) method was developed in this study for enhancing the accuracy of the UV measurement. STM accuracy was verified by both aluminum and a QUS heel phantom, indicating that the STM can determine the phantom thickness within 0.02 mm thickness error and the aluminum calibration step within 0.1 mm thickness error. STM performance was further evaluated using 25 cadaveric human calcanei samples. The UV calculations using STM had a significant better correlation to bone mineral density (BMD) (r = 0.75, p < 0.05), volume fraction (r = 0.72, p < 0.05) and modulus (r = 0.69, p < 0.05) than the UV with fixed thickness. The later correlation coefficients were r = 0.64 for BMD, r = 0.65 for volume fraction, and r = 0.58 for modulus. The nBUA value determined using STM was also highly correlated to BMD (r2 = 0.74) and modulus (r2 = 0.62). This was comparable to the correlation result for BUA (BMD: r2 = 0.76; Modulus: r2 = 0.64). These results suggested that STM technique in scanning ultrasound is capable of determining calcaneus bone thickness and hence enhancing the accuracy of UV measurement. [ABSTRACT FROM AUTHOR]

The problem of sliding-mode control is investigated for a class of uncertain linear systems with input-delay in discrete time. First, a predictor in discrete time is introduced, which converts the original system with input delay to an equivalent system without the explicit appearance of time delay and makes the control problem solvable. Then, sliding-mode controls are constructed for both systems with and without bounded disturbance. Simulation studies show the effectiveness of the control scheme. [ABSTRACT FROM AUTHOR]

We explicitly present a scheme for quantum state sharing of an arbitrary multiqubit state using nonmaximally entangled GHZ states as the quantum channel and generalized Bell states as the measurement basis. The scheme succeeds only probabilistically with its total success probability depending on the degree of entanglement matching between the quantum channel and the generalized Bell states. Security of the scheme is guaranteed by the fact that attacks of an outside eavesdropper or/and an inside dishonest party will inevitably introduce detectable errors. [ABSTRACT FROM AUTHOR]

We analyze GaInN based light emitting diodes emitting in the range of 400-550nm using a new intensity-quantitative spectroscopic cathodoluminescence mapping method. Spectroscopic information of arbitrary sample locations is generated from sequences of quantitative image scans. From the temperature dependence of the intensity, we derive thermal activation energies of the dominant loss processes. Those compare well with the hole binding energies in the piezoelectric and quantized quantum well structures. [ABSTRACT FROM AUTHOR]

Exposure to arsenic in drinking water is known to produce a variety of health problems, including peripheral neuropathy. Auditory, visual and somatosensory impairment have been reported in Mongolian farmers living in the Yellow River Valley, where drinking water is contaminated by arsenic. In the present study, sensory tests, including pinprick and vibration thresholds, were administered to 320 residents with well-water arsenic levels, ranging from non-detectable to 690 μg/L. Vibration thresholds in the second and fifth fingers of both hands were measured using a vibrothesiometer. Drinking water, urine and toenail samples were obtained to assess arsenic exposure and body burden. Regression analyses indicated significant associations of pinprick scores and vibration thresholds with all arsenic measures. Vibration thresholds were more strongly associated with urinary than water or nail arsenic measures, but odds ratios for decreased pinprick sensitivity were highest for the water arsenic measure. Results of the current study indicate neurosensory effects of arsenic exposure at concentrations well below the 1000 μg/L drinking water level specified by NRC, and suggest that non-carcinogenic end-points, such as vibration thresholds, are useful in the risk assessment of exposure to arsenic in drinking water. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrate homoepitaxial growth of GaInN/GaN-based light emitting diodes (LED) on quasi-bulk GaN with an atomically flat polished surface. The threading dislocation densities of the epitaxial layers were 2–5×108 cm−2 which was one order of magnitude less than those grown on c-plane sapphire substrate. The growth defects introduced during the epitaxial process were also one order of magnitude smaller than those grown on the sapphire substrate. The crystalline quality and the optical properties of the epitaxial layer and device performance were much improved. The optical output power of the light emitting diode increased by more than one order of magnitude compared to those on sapphire substrate. [Copyright &y& Elsevier]

Leaching potential of nutrients and heavy metals was evaluated from a peat-based medium (containing 70% peat, 20% perlite, and 10% vermiculite) amended with varying proportions (0%, 25%, 50%, 75%, or 100%) of compost (biosolids and yard waste, 1:1 by weight). The compost contained small amounts of Zn, Cu, Pb, and Cd. However, the leachate fractions of Zn, Cu, Pb, and Cd in compost accounted for only 0.19%, 0.23%, 0.05%, and 0.27%, respectively of the total concentrations. Except for Cu, the concentrations of Zn, Pb, and Cd were higher in the leachates of peat-based medium than the compost amended media. The concentrations of Cd and Pb in the first leachate of the peat-based medium exceeded the drinking water standards (USEPA 1989). However, the concentrations of Cd, Cr, Cu, and Pb in all the compost amended media were below the limit of the drinking water standards. The concentrations of total P and PO4-P in leachates increased with increasing proportion of compost in the media. Concentration of NO3-N in the first leachate was high and decreased in the subsequent leachings for all the compost amended media, These results suggested that the biosolids-yard waste compost may be a safe and acceptable replacement or partial replacement to peat-based medium without increased leachability of nutrients and heavy metals. [ABSTRACT FROM AUTHOR]

A new nonlinear control method for multivariable systems with time delay is presented. It is based on a unique active disturbance rejection concept. The proposed active disturbance rejection controller (ADRC) consists of the tracking differentiator, the extended state observer and the nonlinear proportional derivative (PD) controller. In this approach, the systems with time delay in the input are viewed as higher-order systems without time delay in the input, the approximation error between the nominal systems and real systems and other uncertainties, all of which are seen as ‘disturbance’ by ADRC and are actively compensated. The techniques developed here can be effectively used in engineering systems, such as chemical processes, and this is demonstrated by an example. [ABSTRACT FROM AUTHOR]

Abstract: The thermal-hydraulic performance under conditions of an initial frost growth on the air-side surface, and for subsequent ‘refrosting’ after a defrost period is experimentally studied for folded-louvered-fin, microchannel heat exchangers. In total, five heat exchangers are considered; the thermal performances during one frost-growth cycle for four different fin geometries are compared in terms of overall heat transfer coefficient, pressure drop, and j and f factors; the defrost and refrost characteristics of two heat exchangers are compared to explore geometry effects. Typically, the performance under refrosting conditions becomes periodic and repeatable after the third or fourth refrosting cycle. The allowable frost growth period (before a defrost is required), the defrost requirement, and the thermal-hydraulic performance depend on heat exchanger geometry for the specimens used in this study. [Copyright &y& Elsevier]

A solvent extraction method was used to determine the stability constants of Np(V) complexes with fluoride and sulfate in 1.0M NaClO4 from 25 to 60 °C. The distribution ratio of Np(V) between the organic and aqueous phases was found to decrease as the concentrations of fluoride and sulfate were increased. Stability constants of the 1 : 1 Np(V)-fluoride complexes and the 1 : 1 Np(V)-sulfate and 1 : 2 Np(V)-sulfate complexes, dominant in the aqueous phase under the experimental conditions, were calculated from the effect of [F-] and [SO4 2-] on the distribution ratio. The enthalpy and entropy of complexation were calculated from the stability constants at different temperatures by using the Van't Hoff equation. [ABSTRACT FROM AUTHOR]