Swings

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Swings

  • mood swing
  • voltage swing

  • Terms modified by Swings

  • swing adsorption
  • swing phase

  • Selected Abstracts


    Swing unmasked: the agricultural riots of 1830 to 1832 and their wider implications , Edited by Michael Holland

    ECONOMIC HISTORY REVIEW, Issue 3 2006
    John E. Archer
    No abstract is available for this article. [source]


    Characterization of Ascochyta isolates and susceptibility of pea cultivars to the ascochyta disease complex in Alberta

    PLANT PATHOLOGY, Issue 5 2000
    H. Wang
    The relative virulence of 109 Ascochyta isolates collected from pea fields in Alberta from 1996 to 1998 were evaluated on 10-day-old seedlings by the excised leaf-assay technique. Twenty-eight isolates were avirulent, while the others produced lesions of various sizes on pea leaves. DNA samples from 86 isolates were amplified by the RAPD technique using PCR with single primers. One dominant genotype of Ascochyta pisi was identified throughout Alberta, but variations in virulence were not clearly differentiated by the RAPD technique. Five Ascochyta isolates, four virulent and one avirulent, were used to assess the susceptibility of 20 field pea cultivars available in Alberta, including 13 yellow types and seven green types. Based on symptom development, the yellow-type cultivars Swing, Eiffel and Delta, and the green-type cultivar Orb, were the most susceptible. Of yellow-type cultivars, Voyageur, Carneval and Montana were most resistant to Ascochyta infection. [source]


    Primates of All Types Swing Through the Pages of The Anatomical Record

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 4 2010
    Jeffrey T. Laitman Associate Editor
    No abstract is available for this article. [source]


    Defibrillator Therapies in Hypertrophic Cardiomyopathy: Too Many Swings at Bad Pitches?

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2007
    SUSAN S. KIM M.D.
    [source]


    Mastering Bipolar Disorder , An Insider's Guide to Managing Mood Swings and Finding Balance

    AUSTRALIAN JOURNAL OF RURAL HEALTH, Issue 4 2009
    David Pierce
    No abstract is available for this article. [source]


    Interactive low-dimensional human motion synthesis by combining motion models and PIK

    COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 4-5 2007
    Schubert R. Carvalho
    Abstract This paper explores the issue of interactive low-dimensional human motion synthesis. We compare the performances of two motion models, i.e. Principal Components Analysis (PCA) or Probabilistic PCA (PPCA), for solving a constrained optimization problem within a low-dimensional latent space. We use PCA or PPCA as a first step of preprocessing to reduce the dimensionality of the database to make it tractable, and to encapsulate only the essential aspects of a specific motion pattern. Interactive user control is provided by formulating a low-dimensional optimization framework that uses a Prioritized Inverse Kinematics (PIK) strategy. The key insight of PIK is that the user can adjust a motion by adding constraints with different priorities. We demonstrate the robustness of our approach by synthesizing various styles of golf swing. This movement is challenging in the sense that it is highly coordinated and requires a great precision while moving with high speeds. Hence, any artifact is clearly noticeable in the solution movement. We simultaneously show results comparing local and global motion models regarding synthesis realism and performance. Finally, the quality of the synthesized animations is assessed by comparing our results against a per-frame PIK technique. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Results of treatment when orthopaedic surgeons follow gait-analysis recommendations in children with CP

    DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 7 2008
    Bjørn Lofterød MD
    The aim of the present study was to assess the outcome of orthopaedic surgery in ambulant children with cerebral palsy, when the orthopaedic surgeons followed the recommendations from preoperative three-dimensional gait analysis. 55 children, mean age 10y 11mo, were clinically evaluated by orthopaedic surgeons who proposed a surgical treatment plan. After gait analysis and subsequent surgery, three groups were defined. In group A, there was agreement between clinical proposals, gait-analysis recommendations, and subsequent surgery in 128 specific surgical procedures. In group B, 54 procedures were performed based on gait analysis, although these procedures had not been proposed at the clinical examination. In group C, 55 surgical procedures that had been proposed after clinical evaluation were not performed because of the gait-analysis recommendations. The children underwent follow-up gait analysis 1 to 2 years after the initial analysis. The kinematic results were satisfactory, with improvement in most of the gait parameters in children who had undergone surgery and no significant deterioration in those who were not operated. In group A, there were significant improvements in maximum hip extension in stance, minimum knee flexion in stance, timing of maximum knee flexion in swing and knee range of motion, maximum ankle dorsiflexion in stance, and mean femur rotation in stance. In group B, there were significant improvements in maximum hip extension in stance, minimum knee flexion in stance, and knee range of motion. We conclude that gait analysis was useful in confirming clinical indications for surgery, in defining indications for surgery that had not been clinically proposed, and for excluding or delaying surgery that was clinically proposed. [source]


    Immediate effect of percutaneous intramuscular stimulation during gait in children with cerebral palsy: a feasibility study

    DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 10 2005
    Margo N Orlin PT PhD PCS
    The feasibility of percutaneous intramuscular functional electrical stimulation (P-FES) in children with cerebral palsy (CP) for immediate improvement of ankle kinematics during gait has not previously been reported. Eight children with CP (six with diplegia, two with hemiplegia; mean age 9 years 1 month [SD 1y 4mo; range 7y 11mo to 11y 10mo]) had percutaneous intramuscular electrodes implanted into the gastrocnemius (GA) and tibialis anterior (TA) muscles of their involved limbs. Stimulation was provided during appropriate phases of the gait cycle in three conditions (GA only, TA only, and GA/TA). Immediately after a week of practice for each stimulation condition, a gait analysis was performed with and without stimulation. A significant improvement in peak dorsiflexion in swing for the more affected extremity and dorsiflexion at initial contact for the less affected extremity were found in the GA/TA condition. Clinically meaningful trends were evident for improvements in dorsiflexion kinematics for the more and less affected extremities in the TA only and GA/TA conditions. The results suggest that P-FES might immediately improve ankle kinematics in children with CP. [source]


    Verification of skin-based markers for 3-dimensional kinematic analysis of the equine tarsal joint

    EQUINE VETERINARY JOURNAL, Issue 8 2004
    S. KHUMSAP
    Summary Reasons for performing study: Kinematic studies are usually based on tracking markers attached to the skin. However, complex joints, such as the tarsal joint, function in 3-dimensions (3D), and have therefore necessitated application of the invasive bone pin technique, limiting kinematic studies to the research laboratory. This study investigates the feasibility of using skin-based markers for 3D analysis of tarsal joint motion. Hypothesis: Three-dimensional motions of the tarsal joint can be measured with an acceptable degree of accuracy using skin markers. Methods: Retroreflective markers were attached over the tibial and metatarsal segments. Markers were tracked automatically at trot. Three-dimensional skin correction algorithms were used for correction of skin displacement, and 3D motions derived from the corrected (CSD) and uncorrected (USD) skin displacement were compared with data from a previous study in which those motions were described using bone-fixed markers (BFM) by correlation, root mean square errors (RMS) and shape agreement (SA) of the curves. Results: The RMS of BFM and CSD were smaller than those of BFM and USD for all motions. The correlation coefficients of BFM and CSD were higher than those of BFM and USD. SA was good or fair for all motions except internal/external rotation and medial/lateral translation. Conclusions and potential relevance: With appropriate correction for skin movement relative to skeletal landmarks, skin markers can identify tarsal 3D motions for flexion/extension, abduction/adduction, cranial/caudal translation, and proximal/distal translation, allowing analysis and comparison of information between horses during swing and stance phases. [source]


    Task-induced modulation of motor evoked potentials in upper-leg muscles during human gait: a TMS study

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2002
    Mireille Bonnard
    Abstract The aim of this study was to determine the relative involvement of the corticospinal (CS) pathway in voluntarily controlled walking compared to unconstrained walking. In the voluntarily controlled walking condition, subjects had to walk at the same speed as in unconstrained walking with a mechanical constraint, which is known to affect specifically the upper-leg muscles. The motor cortex was activated transcranially using a focal magnetic stimulation coil in order to elicit motor evoked potentials (MEPs) in the rectus femoris (RF) and the biceps femoris (BF). The magnetic stimulation was delivered at the end of the swing (at 90% of the cycle duration), when the EMG backgrounds were similar in the two experimental conditions. For each subject in each condition, MEPs were measured for several stimulus intensities in order to establish the input/output (I/O) curve (MEPs amplitude plotted against stimulus strength). The results showed a significant increase in the MEPs amplitude of both the RF and BF in voluntarily controlled walking compared to unconstrained walking, which is the first evidence of cofacilitation of MEPs in antagonist upper-leg muscles during human gait. In conclusion, although a lot of studies have emphasized a privileged input of the corticospinal pathway to the distal lower-leg muscles, this study shows that, if a locomotory task requires fine control of the proximal upper-leg muscles, a selective facilitation of MEPs is observed in these muscles. [source]


    Fully Transparent Non-volatile Memory Thin-Film Transistors Using an Organic Ferroelectric and Oxide Semiconductor Below 200,°C

    ADVANCED FUNCTIONAL MATERIALS, Issue 6 2010
    Sung-Min Yoon
    Abstract A fully transparent non-volatile memory thin-film transistor (T-MTFT) is demonstrated. The gate stack is composed of organic ferroelectric poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] and oxide semiconducting Al-Zn-Sn-O (AZTO) layers, in which thin Al2O3 is introduced between two layers. All the fabrication processes are performed below 200,°C on the glass substrate. The transmittance of the fabricated device was more than 90% at the wavelength of 550,nm. The memory window obtained in the T-MTFT was 7.5,V with a gate voltage sweep of ,10 to 10,V, and it was still 1.8,V even with a lower voltage sweep of ,6 to 6,V. The field-effect mobility, subthreshold swing, on/off ratio, and gate leakage currents were obtained to be 32.2,cm2 V,1 s,1, 0.45,V decade,1, 108, and 10,13 A, respectively. All these characteristics correspond to the best performances among all types of non-volatile memory transistors reported so far, although the programming speed and retention time should be more improved. [source]


    Influence of Electric Field on Microstructures of Pentacene Thin-Films in Field-Effect Transistors,

    ADVANCED FUNCTIONAL MATERIALS, Issue 2 2008
    L. Cheng
    Abstract We report on electric-field-induced irreversible structural modifications in pentacene thin films after long-term operation of organic field-effect transistor (OFET) devices. Micro-Raman spectroscopy allows for the analysis of the microstructural modifications of pentacene in the small active channel of OFET during device operation. The results suggest that the herringbone packing of pentacene molecules in a solid film is affected by an external electric field, particularly the source-to-drain field that parallels the a,b lattice plane. The analysis of vibrational frequency and Davydov splitting in the Raman spectra reveals a singular behavior suggesting a reduced separation distance between pentacene molecules after long-term operations and, thus, large intermolecular interactions. These results provide evidence for improved OFET performance after long-term operation, related to the microstructures of organic semiconductors. It is known that the application of large electric fields alters the semiconductor properties of the material owing to the generation of defects and the trapping of charges. However, we first suggest that large electric fields may alter the molecular geometry and further induce structural phase transitions in the pentacene films. These results provide a basis for understanding the improved electronic properties in test devices after long-term operations, including enhanced field-effect mobility, improved on/off current ratio, sharp sub-threshold swing, and a slower decay rate in the output drain current. In addition, the effects of source-to-drain electric field, gate electric field, current and charge carriers, and thermal annealing on the pentacene films during OFET operations are discussed. [source]


    Linearity analysis in pipeline A/D converters

    INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 6 2009
    Behnam Sedighi
    Abstract A method for estimating integral nonlinearity (INL) in pipeline analog-to-digital converters is presented. In this method, errors in each stage are modeled by an equivalent input-referred gain error and an input-referred nonlinearity. For a switched capacitor implementation, the proposed model predicts the maximum statistical INL in terms of capacitor mismatch and also provides an exact formula for INL in terms of finite gain of operational amplifiers. Using this model, it is proved that a high per-stage resolution reduces the power consumption in low-speed converters, whereas in high-speed circuits 1.5-bit or 2.5-bit stage is more advantageous. It is also shown that when voltage swing is below 1,V, the lower limit for the size of the capacitors is mainly determined by thermal noise rather than by INL. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    Power-delay optimization of D-latch/MUX source coupled logic gates

    INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 1 2005
    M. Alioto
    In this paper a design strategy for MUX, XOR and D-latch source coupled logic (SCL) gates is proposed. To this end, an analytical model of the delay and the noise margin as a function of the transistors' aspect ratio and bias current is first introduced. Successively, analytical equations of the transistors' aspect ratio to meet a given noise margin specification are derived as a function of the bias current, and are then used along with the delay model to express the delay as an explicit function of the bias current and noise margin. The simplified delay expression explicitly relates speed performance to power dissipation and the noise margin, thereby providing the designer with the required understanding of the trade-offs involved in the design. Therefore, the criteria proposed allow the designer to consciously manage the power-delay trade-off. The delay dependence on the logic swing is also investigated with results showing that this delay is not necessarily reduced by reducing the logic swing, in contrast with the usual assumption. Since the results obtained are valid for all SCL gates and are independent of the CMOS process used, the guidelines provided afford a deeper understanding of SCL gates from a design point of view. Copyright © 2005 John Wiley & Sons, Ltd. [source]


    Investigation of multi-layered-gate electrode workfunction engineered recessed channel (MLGEWE-RC) sub-50,nm MOSFET: A novel design

    INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 3 2009
    Rishu Chaujar
    Abstract In this paper, a two-dimensional (2D) analytical sub-threshold model for a novel sub-50,nm multi-layered-gate electrode workfunction engineered recessed channel (MLGEWE-RC) MOSFET is presented and investigated using ATLAS device simulator to counteract the large gate leakage current and increased standby power consumption that arise due to continued scaling of SiO2 -based gate dielectrics. The model includes the evaluation of surface potential, electric field along the channel, threshold voltage, drain-induced barrier lowering, sub-threshold drain current and sub-threshold swing. Results reveal that MLGEWE-RC MOSFET design exhibits significant enhancement in terms of improved hot carrier effect immunity, carrier transport efficiency and reduced short channel effects proving its efficacy for high-speed integration circuits and analog design. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    Florigen (II): It is a Mobile Protein

    JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 12 2007
    Yuejun Yang
    Abstract The true identity of florigen , the molecule(s) that migrates from leaves to apical meristem to initiate flowering , was notoriously elusive, having made it almost the "Bigfoot" of plant biology. There was never a lack of drama in the field of florigen study, and florigen researchers have once again experienced such a swing in the last two years. We wrote a minireview last year in this journal (Yu et al. 2006) to excitedly salute, among other discoveries, the notion that the flowering locus T (FT) mRNA might be the molecular form of a florigen. However, this hypothesis was challenged in a little less than two years after its initial proposition, and the original paper proposed that the FT mRNA hypothesis was retracted (Huang et al. 2005; Bohlenius et al. 2007). Interestingly enough, the FT gene previously proposed to encode a florigen was never challenged. Rather, the FT protein, instead of the FT mRNA, is now believed to migrate from leaves to the apical meristem to promote floral initiation. In this update, we will share with our readers some entertaining stories concerning the recent studies of florigen in five different plant species. In addition to the published reports referenced in this update, readers may also refer to our previous minireview and references therein for additional background information (Yu et al. 2006). [source]


    Three-dimensional knee joint kinematics during golf swing and stationary cycling after total knee arthroplasty

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 12 2008
    Satoshi Hamai
    Abstract The expectation of returning to sports activities after total knee arthroplasty (TKA) has become more important to patients than ever. To our knowledge, no studies have been published evaluating the three-dimensional knee joint kinematics during sports activity after TKA. Continuous X-ray images of the golf swing and stationary cycling were taken using a large flat panel detector for four and eight post-arthroplasty knees, respectively. The implant flexion and axial rotation angles were determined using a radiographic-based, image-matching technique. Both the golf swing from the set-up position to the top of the backswing, and the stationary cycling from the top position of the crank to the bottom position of the crank, produced progressive axial rotational motions (p,=,0.73). However, the golf swing from the top of the backswing to the end of the follow-through produced significantly larger magnitudes of rotational motions in comparison to stationary cycling (p,<,0.01). Excessive internal,external rotations generated from the top of the backswing to the end of the follow-through could contribute to accelerated polyethylene wear. However, gradual rotational movements were consistently demonstrated during the stationary cycling. Therefore, stationary cycling is recommended rather than playing golf for patients following a TKA who wish to remain physically active. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source]


    Age-related changes in electromyographic quadriceps activity during stair descent

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2005
    Rana S. Hinman
    Abstract Purpose: To determine the effects of age on (i) the onset of vastus medialis obliquus (VMO) activity relative to that of vastus lateralis (VL) and (ii) the onset of quadriceps activity in terminal swing relative to heel-strike, during stair descent. Methods: Sixty-six healthy men and women with no known knee pathology were recruited from the community and the University of Melbourne. Thirty-three older people aged over 50 (mean (SD) 68 (8) years) and 33 younger people aged under 40 (mean (SD) 25 (4) years) participated. Surface electromyography (EMG) was used to record muscle activity during stair descent. Muscle onset was identified from individual EMG traces with a computer algorithm and validated visually. Results: Both younger and older participants demonstrated a relatively synchronous onset of VMO and VL (i.e. within 10ms of each other) with no differences between the age groups evident (P = 0.262). However older participants activated their quadriceps significantly earlier than the younger group (P < 0.001) even when differences in body mass and speed of stair descent were accounted for. Conclusion: Age-related changes in quadriceps activity are apparent. The clinical implications of such changes are unknown, but increases in joint loading are possible. Earlier quadriceps activation may compensate for balance and strength impairments in older people during challenging activities. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]


    A floral organ moving like a caterpillar for pollinating

    JOURNAL OF SYSTEMATICS EVOLUTION, Issue 2 2010
    Zhong-Jian LIU
    Abstract A new pollination mechanism is reported of an orchid species, Bulbophyllum penicillium, based on a field observation in Southeast Yunnan of China. This species has a sensitive lip, and there is a distance of 2,3 mm between it and column apex. Once the lip is touched by a landing insect, it will move up and down or swing left and right continuously, just like a moving caterpillar. By suck a lip movement, the pollinator, a very small fruit fly (Drosophila sp.) ca. 1 mm in height, will be pressed toward the column apex where anther and stigma are located, and then cross-pollination takes place. This unique mode of pollination, depending on the movement of lip rather than insect itself, has never been found before in either Orchidaceae or other families of angiosperms. [source]


    Literacy in the secondary curriculum

    LITERACY, Issue 1 2001
    David Wray
    The much-signalled extension of the National Literacy Strategy from primary to secondary schools is now in full swing and many secondary teachers are actively looking for practical guidance on ways forward with this national priority. One way of providing such guidance is to outline a common language with which secondary teachers of all subjects can discuss the role of literacy within their subjects. This article puts forward one possible way of developing this common language, by building on the work of Freebody and Luke (1990) in Australia who suggest a literacy resource model. This model is applied to the teaching of literacy within the three core subjects of English, Mathematics and Science. [source]


    A 16-GHz CMOS differential Colpitts VCO for DS-UWB and 60-GHz direct-conversion receiver applications

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2007
    C.-C. Lee
    Abstract A 16-GHz CMOS differential Colpitts VCO fabricated with the 0.18 ,m 1P6M process is presented. The 16-GHz VCO is a good choice for the local oscillator (LO) circuit of the UWB or 60-GHz WPAN direct conversion receiver. The VCO is composed of a PMOS transistor-pair core circuit and two source follower output buffers. The VCO can operate at 16.5 GHz, and the measured phase noise at 1-MHz offset is ,115 dBc/Hz. The power consumption of the VCO core is 12.6 mW. Compared with previous reported works, this VCO has an output power of ,0.9 dBm and about 800-mV output peak-to-peak voltage swing of the VCO core at 16.5 GHz. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2489,2492, 2007; Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/mop.22742 [source]


    Injection-locked GaInp/GaAs HBT frequency divider with stacked transformers

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2007
    Hung-Ju Wei
    Abstract The first integrated GaInP/GaAs heterojunction bipolar transistor (HBT) injection-locked frequency divider (ILFD) with the stacked transformers is demonstrated around 10 GHz. The stacked transformers formed by only two metal layers provide the inductive coupling in the cross feedback and separate biasing for base and collector to allow for the larger output swing in the LC tank and obtaining wide locking range. Under the supply voltage of 5 V and core power consumption of 20.5 mW, the locking range is 7.8% of the center operating frequency. The chip size of the entire ILFD including probing pads is 1.0 × 1.0 mm2. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2602,2605, 2007; Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/mop.22737 [source]


    Electric stress effect on DC-RF performance degradation of 0.18-,m MOSFETS

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2006
    C. C. Chen
    Abstract We have studied the electric stress effect on DC-RF performance degradation of 64 gate fingers 0.18-,m RF MOSFETs. The fresh devices show good transistor's DC to RF characteristics of small sub-threshold swing of 85 mV/dec, large drive current (Id,sat) of 500 ,A/,m, high unity-gain cut-off frequency (ft) of 47 GHz, and low minimum noise figure (NFmin) of 1.3 dB at 10 GHz. The hot carrier stress for 20% Id,sat reduction causes DC gm and ro degradation as well as the lower RF current gain by 2.35 dB, ft reduction to 35.7 GHz, increasing NFmin to 1.7 dB at 10 GHz and poor output impedance matching. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1916,1919, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21813 [source]


    AlGaN/GaN dual-gate high electron mobility transistors on SiC substrates for high-power mixers

    PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7 2005
    K. Shiojima
    Abstract We have demonstrated dual-gate AlGaN/GaN high-electron-mobility transistors on SiC substrates for high-power mixers and examined DC and up-conversion RF measurements with drain-source bias voltages (VDS) to analyze the possible output level. The 0.7 × 300 µm-gate device exhibited the maximum transconductance of 47 mS, maximum RF power of 19.6 dBm and up-conversion gain of 11 dB at 2 GHz when VDS = 15 V. For VDS of over 15 V, the devices occasionally broke down, because, although the device can handle more drain current, but the voltage swing reached the breakdown voltage of about 30 V. These results indicate that a Watt-class output mixer can be easily achieved with this simple dual-gate structure. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Low interface state density AlGaN/GaN MOSHFETs with photochemical vapor deposition SiO2 layers

    PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7 2003
    C. K. Wang
    Abstract High quality SiO2 was successfully deposited onto AlGaN by photo chemical vapor deposition (photo-CVD) using D2 lamp as the excitation source. It was found that the interface state density was only 1.1 × 1011 cm,2 eV,1. AlGaN/GaN metal,oxide,semiconductor heterojunction field effect transistors (MOSHFETs) were also fabricated with such photo-CVD oxide as the insulating layer. Compared with AlGaN/GaN metal,semiconductor HFETs (MESHFETs) with similar structure, it was found that we could reduce the gate leakage current by more than four orders of magnitude by inserting the 32 nm-thick photo-CVD SiO2 layer between AlGaN/GaN and gate metal. With a 1 ,m gate length, it was found that room temperature saturated Ids, maximum gm and gate voltage swing (GVS) of the fabricated nitride-based MOSHFET are 800 mA/mm, 86 mS/mm and 9 V, respectively. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Brief communication: Three-dimensional motion analysis of hindlimb during brachiation in a white-handed gibbon (Hylobates lar)

    AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2010
    Kenji Oka
    Abstract In brachiating gibbons, it is thought that there is little movement in the hindlimb joints and that lateral body movement is quite limited. These hypotheses are based on naked-eye observations, and no quantitative motion analyses of the hindlimbs have been reported. This study quantitatively describes the three-dimensional movements of the lower trunk and distal thigh during continuous-contact brachiation in a white-handed gibbon (Hylobates lar) to evaluate the roles of the trunk and hindlimb. The results revealed that the lower trunk moved both laterally and vertically. The lateral movement of the lower trunk resulted from the lateral inclination of the trunk by gravity. The vertical movement of the trunk was converted into forward velocity, indicating an exchange between potential and kinetic energy. We also observed flexion and extension of the hip, although the excursion was within a small range. In addition, the lateral movement of the hindlimb in thedirection opposite to that of trunk movement helped to reduce the lateral sway of the body. These results suggest that during continuous-contact brachiation a gibbon uses hip flexion and extension motions to increase the kinetic energy in the swing. In addition, fine motions of the hip may restrict the lateral sway of the center of body mass. Am J Phys Anthropol 142:650,654, 2010. © 2010 Wiley-Liss, Inc. [source]


    Experimentally generated footprints in sand: Analysis and consequences for the interpretation of fossil and forensic footprints

    AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2010
    K. D'Août
    Abstract Fossilized footprints contain information about the dynamics of gait, but their interpretation is difficult, as they are the combined result of foot anatomy, gait dynamics, and substrate properties. We explore how footprints are generated in modern humans. Sixteen healthy subjects walked on a solid surface and in a layer of fine-grained sand. In each condition, 3D kinematics of the leg and foot were analyzed for three trials at preferred speed, using an infrared camera system. Additionally, calibrated plantar pressures were recorded. After each trial in sand, the depth of the imprint was measured under specific sites. When walking in sand, subjects showed greater toe clearance during swing and a 7° higher knee yield during stance. Maximal pressure was the most influential factor for footprint depth under the heel. For other foot zones, a combination of factors correlates with imprint depth, with pressure impulse (the pressure-time integral) gaining importance distally, at the metatarsal heads and the hallux. We conclude that footprint topology cannot be related to a single variable, but that different zones of the footprint reflect different aspects of the kinesiology of walking. Therefore, an integrated approach, combining anatomical, kinesiological, and substrate-mechanical insights, is necessary for a correct interpretation. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source]


    Mechanical ventilatory constraints during incremental cycle exercise in human pregnancy: implications for respiratory sensation

    THE JOURNAL OF PHYSIOLOGY, Issue 19 2008
    Dennis Jensen
    The aim of this study was to identify the physiological mechanisms of exertional respiratory discomfort (breathlessness) in pregnancy by comparing ventilatory (breathing pattern, airway function, operating lung volumes, oesophageal pressure (Poes)-derived indices of respiratory mechanics) and perceptual (breathlessness intensity) responses to incremental cycle exercise in 15 young, healthy women in the third trimester (TM3; between 34 and 38 weeks gestation) and again 4,5 months postpartum (PP). During pregnancy, resting inspiratory capacity (IC) increased (P < 0.01) and end-expiratory lung volume decreased (P < 0.001), with no associated change in total lung capacity (TLC) or static respiratory muscle strength. This permitted greater tidal volume (VT) expansion throughout exercise in TM3, while preserving the relationship between contractile respiratory muscle effort (tidal Poes swing expressed as a percentage of maximum inspiratory pressure (PImax)) and thoracic volume displacement (VT expressed as a percentage of vital capacity) and between breathlessness and ventilation . At the highest equivalent work rate (HEWR = 128 ± 5 W) in TM3 compared with PP: , tidal Poes/PImax and breathlessness intensity ratings increased by 10.2 l min,1 (P < 0.001), 8.8%PImax (P < 0.05) and 0.9 Borg units (P < 0.05), respectively. Pulmonary resistance was not increased at rest or during exercise at the HEWR in TM3, despite marked increases in mean tidal inspiratory and expiratory flow rates, suggesting increased bronchodilatation. Dynamic mechanical constraints on VT expansion (P < 0.05) with associated increased breathlessness intensity ratings (P < 0.05) were observed near peak exercise in TM3 compared with PP. In conclusion: (1) pregnancy-induced increases in exertional breathlessness reflected the normal awareness of increased and contractile respiratory muscle effort; (2) mechanical adaptations of the respiratory system, including recruitment of resting IC and increased bronchodilatation, accommodated the increased VT while preserving effort,displacement and breathlessness, relationships; and (3) dynamic mechanical ventilatory constraints contributed to respiratory discomfort near the limits of tolerance in late gestation. [source]


    Factors Associated with Iowa Rural Hospitals' Decision to Convert to Critical Access Hospital Status

    THE JOURNAL OF RURAL HEALTH, Issue 1 2009
    Pengxiang Li PhD
    ABSTRACT:,Context: The Balanced Budget Act (BBA) of 1997 allowed some rural hospitals meeting certain requirements to convert to Critical Access Hospitals (CAHs) and changed their Medicare reimbursement from prospective to cost-based. Some subsequent CAH-related laws reduced restrictions and increased payments, and the number of CAHs grew rapidly. Purpose: To examine factors related to hospitals' decisions to convert and time to CAH conversion. Methods: Eighty-nine rural hospitals in Iowa were characterized and observed from 1998 to 2005. Cox proportional hazards models were used to identify the determinants of time to CAH conversion. Findings: T-test and one-covariate Cox regression indicated that, in 1998, Iowa rural hospitals with more staffed beds, discharges, and acute inpatient days, higher operating margin, lower skilled swing bed days relative to acute days, and located in relatively high density counties were more likely to convert later or not convert before 2006. Multiple Cox regression with baseline covariates indicated that lower number of discharges and average length of stay (ALOS) were significant after controlling all other covariates. Conclusion: Iowa rural hospitals' decisions regarding CAH conversion were influenced by hospital size, financial condition, skilled swing bed days relative to acute days, length of stay, proportion of Medicare acute days, and geographic factors. Although financial concerns are often cited in surveys as the main reason for conversion, lower number of discharges and ALOS are the most prominent factors affecting rural hospitals' decision on when to convert. [source]


    Measurement Entering the 21st Century: A Clear or Blocked Road Ahead?

    AUSTRALIAN ACCOUNTING REVIEW, Issue 21 2000
    MALCOLM C. MILLER
    While progress has been made in rendering financial statements more relevant by the inclusion of current value information, a piecemeal standard-by-standard approach has resulted in a lack of consistency in the specification of the valuation bases. At the international level there is disagreement between standard- setters on a unifjing concept, with some advocating value to the entity and others favouring fair value. The IASC has a high-level steering committee addressing the key issues related to financial performance and it will be interesting to see if it can facilitate the progressive swing to current value by providing a sensible framework within which to report value changes. [source]