Anomalous Features in Surface Impedance of Y-Ba-Cu-O Thin Films: Dependence on Frequency, RF and DC Fields

Two high-quality Y-Ba-Cu-O thin films on MgO substrates have been investigated using the coplanar resonator technique at 8 and 16 GHz. Both films exhibit an anomalous decrease in their surface impedance, Zs as a function of microwave field, Hrf. In zero dc field, Hrf-dependences of Rs and Xs for both the samples are uncorrelated, and only one of the quantities, Rs or Xs, displays anomalous behavior. Here, application of relatively weak (~5 mT) dc magnetic fields, Hdc can produce a correlated decrease of Rs(Hrf) and Xs(Hrf). The dependences of Zs on Hdc in both low and high microwave power regimes were found to be non-monotonic. The frequency dependence of Rs ~ fn, 1.7<n<2.5, remained the same upon the transition from low to high microwave power ranges. The consequences of the reported findings for microwave device applications are briefly discussedComment: 4 pages, 4 figures. Submitted to ASC'2000 Conference Proceeding

Pelvic arthropathy

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The SNAP-1 Machine Vision System

In June 2000, the Surrey Space Centre (SSC) and Surrey Satellite Technology Limited (SSTL) launched the remote inspection demonstrator nanosatellite, SNAP-1 . One of the primary mission objectives of this satellite was to image its companion microsatellite, Tsinghua-1, during the deployment phase of the launch. Later in the mission it is also planned that SNAP-1 will be manoeuvred back within visual range of Tsinghua-1, in order to carry out further imaging experiments whilst the satellites fly in formation. To fulfill its mission, SNAP-1 carries a powerful, innovative and highly integrated Machine Vision System (MVS). This consists of four ulta-minature CMOS video cameras, a software video digitiser, 8Mb of 70ns SRAM and a 220MHz StrongARM processor. The integration of these components provides a low cost, low power consumption, high reliability platform, with enough processing power to capture and process real-time video images. This will enable SNAP-1 to not only compress and return images back to Earth, but to perform high level computer vision functions such as optical target tracking, automatic pose and position estimation and on future SNAP missions perhaps even optically guided docking. This paper therefore details the design, performance and initial results from the SNAP-1 Machine Vision System

„A teraz uczę w szkole katolickiej” – doświadczenia początkujących nauczycieli (Early Career Teachers [ECT]) w szkołach katolickich w Lismore i wynikające z nich wnioski odnośnie do wsparcia formacji. Badania pilotażowe

This study is a preliminary investigation of early career teachers (ECT) working in Catholic schools in a large regional Australian diocese. The key aim of the study is to better understand the factors influencing early career teachers, who begin their teaching careers in Catholic schools, and to apprehend their early experiences as teachers to cater for their continuous formation needs. Key findings identify the openness of ECTs to faith-based experiences and the challenges faced in teaching in a Catholic school. Recommendations for early career teacher support and formation are provided considering the findings of this studyNiniejsze opracowanie relacjonuje badania pilotażowe nauczycieli na początkowym etapie kariery (Early Career Teachers [ECT]) w szkołach katolickich w diecezji Lismore w Australii. Głównym celem badań było lepsze poznanie czynników, warunkujących decyzję o rozpoczęciu kariery nauczycielskiej w szkole katolickiej oraz zrozumienie pierwszych doświadczeń, będących udziałem nauczycieli w szkołach katolickich, tak aby lepiej zaspokajać ich bieżące potrzeby formacyjne. Wyniki badań wskazują na otwartość ECT na doświadczenia oparte na wierze oraz wyzwania stojące przed nauczaniem w szkole katolickiej. W świetle wyników badań przedstawiono zalecenia dotyczące wsparcia i formacji nauczycieli na wczesnym etapie kariery

Interactions of short-term and chronic treadmill training with aging of the left ventricle of the heart

With aging, there is a decline in cardiac function accompanying increasing risk of arrhythmias. These effects are likely to be mechanistically associated with age-associated changes in calcium regulation within cardiac myocytes. Previous studies suggest that lifelong exercise can potentially reduce age-associated changes in the heart. Although exercise itself is associated with changes in cardiac function, little is known about the interactions of aging and exercise with respect to myocyte calcium regulation. To investigate this, adult (12 months) and old (24 months) C57/Bl6 mice were trained using moderate-intensity treadmill running. In response to 10 weeks’ training, comparable cardiac hypertrophic responses were observed, although aging independently associated with additional cardiac hypertrophy. Old animals also showed increased L- and T-type calcium channels, the sodium–calcium exchange, sarcoendoplasmic reticulum calcium ATPase, and collagen (by 50%, 92%, 66%, 88%, and 113% respectively). Short-term exercise training increased D-type and T-type calcium channels in old animals only, whereas an increase in sodium–calcium exchange was seen only in adult animals. Long-term (12 months) training generally opposed the effects of aging. Significant hypertrophy remained in long-term trained old animals, but levels of sarcoendoplasmic reticulum calcium ATPase, sodium–calcium exchange, and collagen were not significantly different from those found in the adult trained animals

Longitudinal Water Permeability of Western Hemlock. I. Steady-State Permeability

Average initial permeability to water of sapwood was found to be 9.6 X 10-10 cm2, that of wetwood from heartwood was 6.64 X 10-10 cm2, and that of normal heartwood was 4.4 X 10-12 cm2. All the specimens were never-dried, approximately 0.95 cm in diameter and 2 cm long, and were embedded in a lucite tube using epoxy resin as binder.Using polyethylene glycol 1000 as an embedding agent, 23% of sapwood pits, 42% of pits in wetwood from heartwood, and 84% of pits in normal heartwood were found to be aspirated. Scanning electron microscopy revealed that the normal heartwood of freeze-dried heartwood was heavily incrusted, but that of wetwood was relatively free of incrustation. High water permeability of wet heartwood was attributed to a low level of pit aspiration and freedom from incrustation.Both sapwood and wetwood exhibited deterioration of permeability with time. In sapwood the cause was considered to be time-dependent pit aspiration because of hydrostatic pressure differentials during testing, but in wetwood the deterioration was attributed to extractives transported by water and deposited on pit membranes to form an impermeable coat of film.A further proposal is that formation of wet pockets during drying of western hemlock lumber is caused by formation of an impermeable zone from the incrustation of pits by extractives during the migration of water, which traps the moisture in lumber

Reviews

The following publications have been reviewed by the mentioned authors;Design Education for the Middle Years, A Teachers' Guide by D. M. Shaw and J. M. Reeve, reviewed by Phil RobertsEducagao Visual I and II by Betamio de Almeida et al, reviewed by Phil RobertsWhat Is a Designer: Things, Places Messages by Norman Potter, reviewed by Phil RobertsDesigning a Present by Norman Potter, reviewed by Phil RobertsA Sense of What is Real by Philip Pacey, reviewed by John LancasterDesign Education at Secondary Level, A Design Education Report, reviewed by Richard KimbellAmerican Porcelain: New Expressions in an Ancient Art by Lloyd E. Herman, reviewed by Michael PaffardThe Mud-Pie Dilemma: A Master Potter's Struggle to Make Art and Ends Meet by John Nance, reviewed by Michael PaffardWoodcarving for Beginners by Art McKellips, reviewed by Bernard AylwardAppreciation of Materials and Design by T. Pettit, reviewed by Bernard AylwardWhy It is Like This by Bernard Aylward, reviewed by Richard Kimbel

K2p3.1 protein is expressed as a transmural gradient across the rat left ventricular free wall

Introduction: K 2p 3.1, also known as TASK-1, is a twin-pore acid-sensitive repolarizing K + channel, responsible for a background potassium current that significantly contributes to setting the resting membrane potential of cardiac myocytes. Inhibition of I K2p3.1 alters cardiac repolarization and is proarrhythmogenic. In this study, we have examined the expression of K 2p 3.1 and function of this channel in tissue and myocytes from across the left ventricular free wall. Methods and Results: Using fluorescence immunocytochemistry, the expression of K 2p 3.1 protein in myocytes from the subendocardial region was found to be twice (205% ± 13.5%) that found in myocytes from the subepicardial region of the left ventricle (100% ± 5.3%). The left ventricular free wall exhibited a marked transmural gradient of K 2p 3.1 protein expression. Western blot analysis confirmed significantly higher K 2p 3.1 protein expression in subendocardial tissue (156% ± 2.5%) than subepicardial tissue (100% ± 5.0%). However, there was no difference in K 2p 3.1 messenger RNA expression. Whole-cell patch clamp identified I K2p3.1 current density to be significantly greater in myocytes isolated from the subendocardium (7.66 ± 0.53 pA/pF) compared with those from the subepicardium (3.47 ± 0.74 pA/pF). Conclusions: This is the first study to identify a transmural gradient of K 2p 3.1 in the left ventricle. This gradient has implications for understanding ventricular arrhythmogenesis under conditions of ischemia but also in response to other modulatory factors, such as adrenergic stimulation and the presence of anesthetics that inhibits or activates this channel

Contributors to the January Issue/Notes

Notes by Leon L. Lancaster, Edwin Daniel O\u27Leary, Richard F. Sullivan, Edward F. Grogan, Jr., and Samuel L. Devine

Contributors to the January Issue/Notes

Notes by Leon L. Lancaster, Edwin Daniel O\u27Leary, Richard F. Sullivan, Edward F. Grogan, Jr., and Samuel L. Devine