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Investigates some of the properties of strained-layer quantum-well heterostructure (SL-QWH) current injection lasers to evaluate the potential of the strained-layer lasers. Cross section of SL-QWH laser grown by molecular beam epitaxy; Room temperature emission spectra for SL-QWH laser; Degradation of a SL-QWH laser during 1000 h of operation.

Objectives: To determine bone morphogenetic proteins (BMPs) and Dickkopf homologue-1 (Dkk-1) levels in ankylosing spondylitis (AS).Method: Serum BMPs and Dkk-1 were measured in 72 AS patients and 30 healthy controls. For AS patients, we recorded the demographic data, disease activity, functional index, and global assessment with questionnaires, and image changes with roentgenography. We also measured human leucocyte antigen-B27 and systemic inflammatory reactants.Results: BMPs were higher but Dkk-1 was significantly lower in AS patients than in controls. Dkk-1 was higher in AS patients who received non-steroidal anti-inflammatory drugs (NSAIDs) regularly in the past year (p = 0.001). Serum BMP-7 level and the BMP-7/Dkk-1 ratio correlated significantly with sacroiliitis severity, Bath Ankylosing Spondylitis Radiology Index (BASRI)-total, modified Stoke Ankylosing Spondylitis Spinal Score, and disease duration. There were also significant positive correlations among serum levels of BMP-2, -4, and -6, BASRI-total, and disease duration (p < 0.05). However, BMP-2/Dkk-1 was only significantly correlated with disease duration. The calculated area under the standard receiver operating characteristics curve suggested that BMP-2/Dkk-1 and serum BMP-2 are good indicators to predict disease activity, functional index, and patient global assessment in AS patients.Conclusion: BMPs and BMPs/Dkk-1 were significantly correlated with disease activity, and radiological and functional indices in AS patients. Dkk-1 was lower in AS patients than in controls. Among AS patients, Dkk-1 was higher in those taking NSAIDs regularly. BMP or Dkk-1 may be taken as a biomarker for disease severity or a treatment outcome predictor in AS, but this needs further study. [ABSTRACT FROM AUTHOR]

Burrowing is an energetically costly form of locomotion that has evolved multiple times in mammals. Burrowing performance is associated with varying degrees of morphological specialization and is also affected by the characteristics of the substrate that animals burrow in. Moles (Talpidae) are well known for their specialized forelimbs and extreme dedication to life underground. In this study, we investigated how soil compactness affects burrowing performance in two sympatric mole species, eastern moles ( Scalopus aquaticus) and hairy-tailed moles ( Parascalops breweri). We measured burrowing speed, the amount of soil moved, rate of soil transport, tunnel length, activity level and the tendency to burrow over long distances, and tested how these variables changed in response to loose, intermediate and compact soils. We found that increasing soil compactness impedes tunneling performance as evidenced by reduced burrowing speed, increased soil transport, shorter tunnels, shorter activity time and less time spent burrowing continuously. Eastern moles built longer tunnels than hairy-tailed moles as soil compactness increased. This difference is linked to burrowing for longer times and distances, not higher burrowing speeds or rates of soil transport. Differences in performance between the two species may be associated with differences in the structure and extent of their burrow systems or the morphology of their forelimbs. They may also reflect preferences for loose (hairy-tailed moles) or compact soils (eastern moles). [ABSTRACT FROM AUTHOR]

Analyzes the growth of single crystals of the superconductor YBa[sub2]Cu[sub3]O[suby] from a mixture of solid phase YBa[sub2]Cu[sub3]O[suby] and liquid phase silver. Details of the process involved in growing high J[subc] superconducting yttrium (Y)-123 crystals from a mixture of stoichiometric Y-123 and Ag[sub2]; Description of stoichiometric Y-123 powder; Comparison between single and cube-like crystals; Effect of the addition of Ag[sub2]O on the stoichiometric Y-123 powder.

Presents a study which focused on copper spin orientation in titanium(barium strontium)praseodymium copper[sub2]oxygen[sub7]. Methods; Results; Discussion.

Motivated by the description of the C*-algebra of the affine automorphism group N 6 , 28 of the Siegel upper half-plane of degree 2 as an algebra of operator fields defined over the unitary dual N 6 , 28 ˆ of the group, we introduce a family of C*-algebras, which we call almost C 0 ( K ) , and we show that the C*-algebra of the group N 6 , 28 belongs to this class. [ABSTRACT FROM AUTHOR]

Abstract: We give a characterisation of the compact separating maps between continuous fields of Banach spaces, and provide some applications. [Copyright &y& Elsevier]

CHIEN T-W., LIN Y-F., CHANG C-H., TSAI M-T. & UEN Y-H. (2012) European Journal of Cancer Care Using a bubble chart to enhance adherence to quality-of-care guidelines for colorectal cancer patients This study examines whether a higher rate of physician adherence to quality-of-care indicators for colorectal cancer patients is associated with improved survival and using a bubble chart to help interpret physician performance. A set of 13 core measures was used to evaluate the quality of care in 708 colorectal cancer patients treated from 2004 to 2007 at a hospital in Taiwan. A 100% adherence standard was used to measure the relationship of adherence to patient survival. Each indicator assigned by each cancer stage was dichotomously coded. The associations between the adherence and survival rates and demographic characteristics were assessed using Cox's proportional hazard regression. Physician adherence to core indicators was plotted using a bubble chart to motivate physicians' performance adhering to quality-of-care guidelines for colorectal cancer patients. The 100% adherence rate criterion contributed to a relatively low hazard ratio of 0.36 (95% confidence interval, 0.14-0.85; P= 0.02). The association between the adherence rate and survival indicated significant improvements for stage III patients compared with stage I patients. A graphical representation of bubble charts helped to monitor physician performance, which improved the adherence rate to quality-of-care guidelines for colorectal cancer patients. [ABSTRACT FROM AUTHOR]

Background: Overcrowding in emergency departments (ED) around the world is an increasingly serious problem with an adverse impact on both patient flow and patient outcomes. A significant contributing factor to ED overcrowding is possibly due to readmission. Risk factors for readmission in patients admitted from ED are rarely studied, particularly in Asian countries where the length of stay is reportedly longer. Methods: A retrospective study of patients admitted to general medical wards from the ED of a referral centre in northern Taiwan from November 2009 to April 2010 was conducted. The primary outcome was 30-day hospital readmission and clinical characteristics were analysed for predictors of readmission. Results: Of the recruited 2698 patients, 451 (16.7%) were readmitted within 30 days after discharge. Age, gender, marital status and the activities of daily living (Barthel's score) were not associated with 30-day readmission. Higher Charlson score ((score 2-4) hazard ratio (HR): 1.42, 95% confidence interval (CI): 1.07-1.89; (score >4) HR: 1.93, 95% CI: 1.37-2.73), longer hospital stay ((8-14 days) HR: 1.51, 95% CI: 1.17-1.95; (15-28 days) HR: 1.64, 95% CI: 1.22-2.19; (>28 days) HR: 1.97, 95% CI: 1.43-2.71), and presence of underlying active malignancy (HR: 1.66, 95% CI: 1.27-2.16) and anaemia (HR: 1.26, 95% CI: 1.02-1.55) were independently associated with readmission. Conclusion: Medical patients admitted from the ED of a referral centre have a 30-day readmission rate of 16.7%. Post-discharge care should focus on patients with higher Charlson score, longer hospitalisation, anaemia and underlying active malignancy, which are independent predictive factors for 30-day readmission. [ABSTRACT FROM AUTHOR]

End-pumped by a single-stripe 805-nm diode laser, a maximum continuous-wave output power of 290 mW with slope efficiency of 42% and 90 mW with slope efficiency of 44% around 2 µm were achieved in a 1.6-mm-thickness, unprocessed 7.2 at.% Tm3+:BaGd2(MoO4)4 cleavage plate in a hemispherical and plano–plano cavities, respectively, when the absorbed pump power was 830 mW. The dependence of the polarization of output laser on the output coupler transmission was investigated. The influence of upconversion on the laser performance was analyzed. The results show that the unprocessed Tm3+:BaGd2(MoO4)4 cleavage plate is a promising 2-µm laser gain medium pumped by diode laser around 808 nm. [ABSTRACT FROM AUTHOR]

A Pr3+:NaGd(MoO4)2 single crystal has been grown by the Czochralski method. The polarized absorption spectra, polarized fluorescence spectra, and fluorescence decay curves of the crystal were measured at room temperature. The Judd–Ofelt intensity parameters Ω t, q ( t=2,4,6) and the spectroscopic parameters related to the 3 P 0 and 1 D 2 multiplets were obtained and analyzed. The decay mechanisms for the 3 P 0 and 1 D 2 multiplets were also discussed. [ABSTRACT FROM AUTHOR]

An Er3+:Bi2(MoO4)3 single crystal has been grown by the Czochralski technique. The Stark sublevels of the 4I15/2 and 4I13/2 multiplets of Er3+ ions in the crystal were determined. The polarized absorption spectra, polarized fluorescence spectra, and fluorescence decay curve of the crystal were measured at room temperature and the relevant spectroscopic parameters, including the Judd–Ofelt intensity parameters, spontaneous emission probability, fluorescence branching ratio, radiative lifetime, and stimulated emission cross section, were estimated. The effect of re-absorption on the spectroscopic parameters was discussed. When the crystal was excited at 977 nm, up-conversion green fluorescence was observed and discussed. [ABSTRACT FROM AUTHOR]

Background and purpose:It has been found that 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) exert various vascular protective effects, beyond their cholesterol-lowering property, including inhibition of platelet-dependent thrombus formation. The objective of the present study was to determine whether the nitric oxide (NO)/cyclic GMP-mediated processes in platelets contribute to the anti-aggregatory activity of simvastatin.Experimental approach:After rabbit platelets were incubated with simvastatin for 5 min, aggregation was induced and the platelet aggregation, nitric oxide synthase activity, guanylyl cyclase activity, NO and cyclic GMP formation were measured appropriately.Key results:Treatment with simvastatin concentration-dependently inhibited platelet aggregation induced by collagen or arachidonic acid with an IC50 range of 52–158 μM. We also demonstrated that simvastatin (20–80 μM) concentration-dependently further enhanced collagen-induced NO and cyclic GMP formation through increasing NOS activity (from 2.64±0.12 to 3.52±0.21–5.10±0.14 μmol min−1 mg protein−1) and guanylyl cyclase activity (from 142.9±7.2 to 163.5±17.5–283.8±19.5 pmol min−1 mg protein−1) in the platelets. On the contrary, inhibition of platelet aggregation by simvastatin was markedly attenuated (by about 50%) by addition of a nitric oxide synthase inhibitor, a NO scavenger or a NO-sensitive guanylyl cyclase inhibitor. The anti-aggregatory effects of simvastatin were significantly increased by addition of a selective inhibitor of cyclic GMP phosphodiesterase.Conclusions and implications:Our findings indicate that enhancement of a NO/cyclic GMP-mediated process plays an important role in the anti-aggregatory activity of simvastatin.British Journal of Pharmacology (2008) 153, 1281–1287; doi:10.1038/bjp.2008.19; published online 11 February 2008 [ABSTRACT FROM AUTHOR]

Abstract: ATP-sensitive potassium (K atp ) channels play an important role in controlling insulin secretion and vascular tone as well as protecting neurons under metabolic stress. We have previously demonstrated that stimulation of the K atp channel by nitric oxide (NO) requires activation of Ras- and extracellular signal-regulated kinase (ERK) of the mitogen-activated protein kinase (MAPK) family. However, the mechanistic link between ERK and the K atp channel remained unknown. To investigate how ERK modulates the function of K atp channels, we performed single-channel recordings in combination with site-directed mutagenesis. The Kir6.2/SUR1 channel, a neuronal K atp channel isoform, was expressed in human embryonic kidney (HEK) 293 cells by transient transfection. Direct application of the activated ERK2 to the cytoplasmic surface of excised, inside-out patches markedly enhanced the single-channel activity of Kir6.2/SUR1 channels. The normalized open probability (NPo) and opening frequency were significantly increased, whereas the mean closed duration was reduced. The single-channel conductance level was not affected. The ERK2-induced stimulation of Kir6.2/SUR1 channels was prevented by heat-inactivation of the enzyme. Furthermore, alanine substitutions of T341 and S385 to disrupt the potential ERK phosphorylation sites present in the Kir6.2 subunit significantly abrogated the stimulatory effects of ERK2, while aspartate substitutions of T341 and S385 to mimic the (negative) charge effect of phosphorylation rendered a small yet significant reduction in the ATP sensitivity of the channel. Taken together, here we report for the first time that ERK2/MAPK activates neuronal-type K atp channels, and this stimulation requires ERK phosphorylation of the Kir6.2 subunit at T341 and S385 residues. The ERK2-induced K atp channel stimulation can be accounted for by changes in channel gating that destabilize the closed states and by reduction in the ATP sensitivity. As Kir6.2 is the pore-forming subunit of K atp channels, ERK2-mediated phosphorylation may represent a common mechanism for K atp channel regulation in different tissues. [Copyright &y& Elsevier]

An Er3+/Yb3+-codoped Li6Y(BO3)3 crystal was grown by the Czochralski method. The polarized absorption spectra and the fluorescence decay curve were recorded. The efficiency of energy transfer from Yb3+ to Er3+ ions was estimated. Quasi-continuous-wave output power of 325 mW at 1594 nm was realized under the absorbed pump power of 10.4 W in a hemispherical cavity. The absorbed pump threshold and slope efficiency of the laser are 6.0 W and 7.2%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The first part of this series of papers addressed the theory, numerical implementation and parameter investigations of two further explored Vold–Kalman-filtering order-tracking techniques. A proposed tunable weighting factor for effectively distinguishing and separating both close and crossing order components of signals measured from rotary machines was implemented and examined. Additionally, parameters influencing waveform-tracking performance were investigated. Here, in the second paper of the series, geometric analysis to interpret dynamic signatures using order-tracking schemes is first summarised. To justify the effectiveness of applying developed techniques in practical works, three experimental tasks are accomplished. One is the separation of two close orders arising from flexible coupler imbalancing and gear meshing of a transmission-element test bench. The second task is the investigation of the dynamic characteristics of an electric scooter with a planetary gear set and four stages of speed-reduction gears using the implemented order-tracking techniques. The interactions between order components and structure resonances can be decoupled and distinguished precisely. The third task shows the successful ranking for different signature components of passby noise generated from an electric scooter with CVT transmission. This demonstrates the superiority of the angular-displacement Vold–Kalman-filtering order-tracking technique for analysing and interpreting dynamic signals arising from the operation of rotary machines. [Copyright &y& Elsevier]

Abstract: The papers explore and present advanced order-tracking techniques using the Vold–Kalman filter with a weighting factor to distinguish and separate both close and cross-order components in signals measured from rotary machines. In the first part of this series of papers, theoretical formulation, numerical implementation, and parameter investigation are performed. Especially, a weighting-factor parameter is further examined and implemented to tune and attain variant tracking filter characteristics. Significant comparisons to other conventional order-tracking schemes such as the windowed Fourier transform and the resampling method are made to highlight superior characters of the implemented techniques. Additionally, comprehensive parameter investigations, such as weighting factor, acquired reference shaft speed and noise/unwanted signature effects on tracking results, are also performed for guidelines upon using these techniques. Engineering applications on the noise–vibration–harshness concerns associated with a laboratory transmission-component test-bench and two types of electrical scooters are stated in the second part of the papers. [Copyright &y& Elsevier]

The tracking and almost disturbance decoupling problem of multi-input multi-output nonlinear systems based on the feedback linearisation approach are studied. The main contribution of this study is to construct a controller, under appropriate conditions, such that the resulting closed-loop system is valid for any initial condition and bounded tracking signal with the following characteristics: input-to-state stability with respect to disturbance inputs and almost disturbance decoupling, that is, the influence of disturbances on the L2 norm of the output tracking error can be arbitrarily attenuated by changing some adjustable parameters. One example, which cannot be solved by the first paper of the almost disturbance decoupling problem on account of requiring some sufficient conditions that the nonlinearities multiplying the disturbances satisfy structural triangular conditions, is proposed to exploit the fact that the tracking and the almost disturbance decoupling performances are easily achieved by the proposed approach. To demonstrate the practical applicability, a famous half-car active suspension system has been investigated. [ABSTRACT FROM AUTHOR]

The design and experimental demonstrations of a planar inverted-F antenna (PIFA) are presented. The physical parameters of the antenna, including shorting plate width, antenna input impedance, antenna thickness and ground plane dimensions, are studied. The influence of various parameters on antenna characteristics has been investigated using simulation software IE3D and experimental results. Comparisons with measured results on fabricated antenna structures are provided for simulation validation. Simple semi-empirical formulas of the operational frequency and input impedance on the antenna have also been obtained. These results are very useful in the design of PIFA. [ABSTRACT FROM AUTHOR]

The design of an antenna consisting of two strip monopoles printed on the same side of an electrically thin dielectric substrate, and incorporating the use of a 50ω microstrip feed line with an open-circuited tuning stub, is presented. The proposed antenna is designed to have dual-band operation suitable for applications in DCS (1710-1880 MHz) and WLAN (2400-2484 MHz) bands. The dual-band antenna is simple in design, and the lengths of the antenna's larger and smaller strips can easily control the lower and upper operating frequencies, respectively. The influence of various parameters on antenna characteristics has been investigated using simulation software and experimental results. Optimal results and omnidirectional radiation patterns are given for the proposed antenna operating in the 1800 MHz/2450 MHz bands. Details of the dual-band design and design parametric study are presented and discussed. [ABSTRACT FROM AUTHOR]

One objective of this work is to determine the optimal combination of the probe diameter and grid distance for freeform surface measurement, and another is to determine the optimal parameters for the local Shepard interpolation. The optimal combination of the probe diameter and grid distance for freeform surface measurement was determined through a Taguchi matrix experiment. The smaller the probe diameter and grid distance, the better the accuracy of the surface normal based on the configured matrix experimental result. The optimal parameters, namely the exponent μ and the radius R, for the local Shepard interpolation were determined by using the minimisation method of the root-mean-square normalised error (RMSNE) between the measured data points and the theoretical data points on a standard steel ball surface. The optimal parameters determined were actually applied to the measurement of a freeform surface (mouse surface) on a coordinate measuring machine (CMM). The local Shepard interpolation method was used to interpolate 16 control points from 1054 measured data points. Bi-cubic Bezier- and B-spline surface CAD models were constructed through these interpolated control points. [ABSTRACT FROM AUTHOR]

Demonstrates the usefulness of a low-temperature cleaning technique for the gallium arsenide surface. Reason for the interest of research groups in the epitaxial growth of lattice-matched Ca[subx]Sr[sub1-x]F[sub2] on gallium arsenide and in the formation of epitaxial iGaAs/(Ca,Sr)F[sub2]/GaAs structures; Auger spectrum of the GaAs surface; Factors that allow the ambient transfer of the GaAs substrate.

A novel single-layer, proximity-fed technique for a slot-coupled circularly polarised square patch antenna operated in the ultra-high frequency band is presented. In the proposed design a pair of radiating square patches with a cross-slot and a microstrip feed line are both etched on the top of a microwave substrate, and a coupling arrow-shaped slot is etched on the bottom of this substrate. Simulated and measured results indicate that the proposed structure can achieve circular polarisation operation. Proper adjustment of the feed coupling gap distance between the patch and the feed line results in good impedance matching and circularly polarised radiation, and an impedance bandwidth (VSWR≤2) of about 3.74% and a 3 dB axial-ratio bandwidth of about 1.62% were obtained. [ABSTRACT FROM AUTHOR]

An efficient and high output power laser has been realized for an Er:Yb:YAl3(BO3)4 crystal end pumped by a 970 nm diode laser. Under the absorbed pump power of 15.5 W, quasi-continuous-wave output power of 2.0 W at 1.5–1.6 μm has been obtained in a hemispherical cavity. The laser had an absorbed pump threshold power of 4.7 W and a slope efficiency of 21%. The influence of the laser output power and output coupler transmission on the output laser spectra has also been investigated. [ABSTRACT FROM AUTHOR]

A miniature printed H-shaped narrow slot antenna fed by a coplanar waveguide (CPW) is proposed for WLAN applications in the 2.4 GHz band. The antenna with a simplified open-end tuning stub is also proposed. The prototype has been designed and fabricated and found to have a bandwidth of 13.5%, and the radiation pattern measured at resonance is very close to omnidirectional in the H-plane. The characteristics of the proposed antenna has been investigated using simulation software HFSS and experimental results. The measured and simulated results show excellent agreement. [ABSTRACT FROM AUTHOR]

A highly compact (25 × 25 × 0.8 mm³) dual-band folded square-loop antenna is proposed for reading near-field RF identification (RFID) tags. The antenna has a strong and uniform magnetic field in the nearfield zone of the square loop. The side length of the square loop (~λ/16) generates resonant frequencies in two conventional modes (0.5λ and 1.0λ). Experimental interrogation of a small RFID button tag attached to a blood sample collection tube showed that the antenna has a small interrogation zone (15 × 15 mm²), which avoids unnecessary interrogation. Experiments also showed that with an input power of 25 dBm, the antenna can tag at a distance of up to 40 mm, which confirmed its suitability for reading button-type RFID tags attached to blood sample collection tubes and other specimen containers. [ABSTRACT FROM AUTHOR]

Pumped by a Ti:sapphire laser, a passively Q-switched laser oscillation from an unprocessed Nd:LaB3O6 cleavage microchip with a Cr4+:YAG saturable absorber has been demonstrated. The influence of the transmission of the output coupler on the pulse width and repetition rate at various absorbed pump powers has been investigated. A pulse with 2.8 μJ energy, 2.2 ns duration, and 29 kHz repetition rate at 1060 nm was obtained at the absorbed pump power of 1.25 W and output coupler transmission of 3.2%, which results in 1.25 kW peak power. The polarization and spectral properties of laser radiation were measured. [ABSTRACT FROM AUTHOR]

The improvement of the laser performances of an unprocessed 5.6 at. % Nd3+:LaB3O6 cleavage microchip has been reported. Pumped by a Ti:sapphire laser at 871 nm, quasi-cw output laser power up to 395 mW around 1060 nm wavelength with slope efficiency near 52% has been obtained in an end-pumped plano-plano resonator. The influence of the ratio between the cavity mode and pump beam area on the laser performances and laser spectra at various output powers has been investigated. The experimental results have shown that the cleavage technique can become a practical and effective method to obtain the microchip laser medium easily and directly. [ABSTRACT FROM AUTHOR]

A novel single-layer, dual-fed technique for a bidirectional radiated circularly polarised square-ring antenna operated in the UHF band is presented. The two feed ports of the square-ring radiating element are placed in orthogonal directions and connected to a feeding network with a Wilkinson power divider in the same plane. Properly adjusting the size of the capacitive coupling groundplane results in good impedance matching and circularly polarised radiation, and a broad impedance bandwidth (S11≤-10 dB) of about 45.2% and a 3 dB axial-ratio bandwidth of about 8.7% were obtained. [ABSTRACT FROM AUTHOR]

The article presents a letter to the editor commenting on a study on urinary protein markers in lupus nephritis.

Presents a study which examined the relationship of the performance of a double-heterostructure (DH) laser with various polishing techniques used for gallium arsenide (GaAs) substrates preparation. Description of the process of polishing; Fabrication of broad-area laser diodes; Results for DH lasers with GaAs active regions.

We here report three cases with RNA-specific adenosine deaminase ( I ADAR1 i ) mutations causing psoriasis concomitant with dyschromatosis symmetrica hereditaria (DSH). Co-existence of psoriasis and DSH implies that patients with I ADAR1 i mutations may have decreased A-to-I RNA editing in keratinocytes, leading to the development of psoriasis. [Extracted from the article]