Height Range (height + range)

Distribution by Scientific Domains


Selected Abstracts


Experimental study of mode-coupling strength of AT-cut quartz resonators with high mesa step height

ELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 1 2009
Shigeyoshi Goka
Abstract In this paper, the bi-mesa resonators, which can be fabricated with very high mesa steps, were fabricated, and their frequency,temperature (f,T) characteristics were measured as an index of the mode-coupling strength. Since the mode-coupling affects the first-order temperature coefficient of the TS-1 mode, the f,t curve of the pure TS-1 mode rotates clockwise depending on the mode-coupling strength. The experimental results showed that the tendency of the first-order coefficients of the measured f,T data were in good agreement with the calculated mode-coupling strength in the mesa height range of 0 to 50%. These results indicate the validity of the calculated mode-coupling strength between TS-1 and TF modes. It is also shown that choosing lower mesa height is desirable because the face-shear modes caused by the X,Z, boundary tend to couple with the TS-1 mode when the mesa step is very high. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 92(1): 34,38, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10227 [source]


Obesity in adults and children: a call for action

JOURNAL OF ADVANCED NURSING, Issue 2 2001
Karyn Holm PhD RN FAAN
Obesity in adults and children: a call for action Obesity/overweight in adults and children is a worldwide health problem associated with substantial economic burden as measured by paid sick leave, life and disability insurance rates, and obesity-related physician visits and hospital stays. Overweight/obese people experience hypertension, elevated cholesterol, and type 2 diabetes and suffer more joint and mobility problems than people within the normal weight for height range. While there is need to understand individual behaviors that can be modified to promote weight loss and weight maintenance, there is as great a need to consider contextual factors at the societal level that can impede or even sabotage weight control efforts. In every country with improved living standards people will continue to eat too much and engage in too little physical activity. The call for action is for all modernized societies to alter environments and attitudes to support, rather than hinder, healthy dietary intake and being physically active. [source]


Comparison of Indian reference equations for spirometry interpretation

RESPIROLOGY, Issue 5 2007
Ashutosh N. AGGARWAL
Background and objectives: It would be desirable in a large country such as India that a single set of reference equations be used to interpret lung function tests performed across the entire country. This study compared north, west and south reference equations in interpreting spirometry results in north Indian patients. Methods: Spirometric records of 27383 patients aged 16,65 years were assessed. Spirometric values for FVC, FEV1 and FEV1%FVC values derived from north, west and south Indian reference equations were compared. Differences in the lower limit of normal (LLN) were studied across the age and height range of the study group to determine if there was any clinically significant difference in the three derived values. Results: The north and west Indian equations was discordant in 22.1% instances, and the north and south Indian equations in 12.9% instances, with kappa estimates of agreement being 0.626 and 0.781, respectively. Most of the patients with abnormal spirometry using north Indian equations were erroneously interpreted to have normal spirometry using west or south Indian equations. The south Indian equations underpredicted LLN for FVC and FEV1 for most men and women. The west Indian equations underpredicted LLN for FVC and FEV1 in all men, and in younger and short statured women. Conclusions: North, west and south Indian reference equations do not yield equivalent results for spirometry interpretation in north Indian patients. [source]


Model studies of the interannual variability of the northern-hemisphere stratospheric winter circulation: The role of the quasi-biennial oscillation

THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 574 2001
L. J. Gray
Abstract A series of experiments are described that examine the sensitivity of the northern-hemisphere winter evolution to the equatorial quasi-biennial oscillation (QBO). The prime tool for the experiments is a stratosphere-mesosphere model. The model is integrated over many years with the modelled equatorial winds relaxed towards observed values in order to simulate a realistic QBO. In experiment A the equatorial winds are relaxed towards Singapore radiosonde observations in the height region 16-32 km. In contrast to previous modelling studies, the Holton-Tan relationship (warm/cold winters associated with easterly/westerly QBO winds in the lower stratosphere) is absent. However, in a second experiment (run B) in which the equatorial winds are relaxed towards rocketsonde data over the extended height range 16-58 km, a realistic Holton-Tan relationship is reproduced. A series of further studies are described that explore in more detail the sensitivity to various equatorial height regions and to the bottom-boundary forcing. The experiments suggest that the evolution of the northern-hemisphere winter circulation is sensitive to equatorial winds throughout the whole depth of the stratosphere and not just to the lower-stratospheric wind direction as previously assumed. [source]


Metastable and stable states of xanthan polyelectrolyte complexes studied by atomic force microscopy

BIOPOLYMERS, Issue 3 2004
Gjertrud Maurstad
Abstract The compaction of the semiflexible polysaccharide xanthan with selected multi- and polyvalent cations was studied. Polyelectrolyte complexes prepared at concentrations of 1,2 ,g/ml were observed by tapping mode atomic force microscopy. High-molecular-weight xanthan compacted with chitosan yields a blend of mainly toroidal and metastable structures and a small fraction of rod-like species. Polyelectrolyte complexes of xanthan with polyethylenimine and trivalent chromium yielded similar structures or alternatively less well packed species. Racquet-type morphologies were identified as kinetically trapped states occurring on the folding path toward the energetically stable state of the toroids. Thermal annealing yielded a shift of the distribution of xanthan,chitosan morphologies toward this stable state. Ensembles of toroidal and rod-like morphologies of the xanthan,chitosan structures, collected using an asphericity index, were analyzed. The mean height of the toroids increased upon heating, with a selective increase in the height range above 2 nm. It is suggested that the observed metastable structures are formed from the high-molecular-weight fraction of xanthan and that these are driven toward the toroidal state, being a low-energy state, following annealing. Considered a model system for condensation of semiflexible polymers, the compaction of xanthan by chitosan captures the system at various stages in the folding toward a low-energy state and thus allows experimental analyses of these intermediates and their evolution. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004 [source]


Roughness Characterization through 3D Textured Image Analysis: Contribution to the Study of Road Wear Level

COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 2 2004
M. Khoudeir
The microtexture is defined as surface irregularities whose height ranges from 0.001 mm to 0.5 mm and whose width is less than 0.5 mm (Alvarez and Mprel, 1994). The deterioration due to the road traffic, especially polishing effect, involves a change in the microtexture. So, we suggest a method to characterize, through image analysis, wear level or microroughness of road surfaces. We propose then, on one hand a photometric model for road surface, and, on the other hand, a geometrical model for road surface profile. These two models allow us to develop roughness criteria based on the study of the statistical properties of: the distribution of the gray levels in the image, the distribution of the absolute value of its gradient, the form of its autocorrelation function, and the distribution of its curvature map. Experiments have been done with images of laboratory-made road specimens at different wear levels. The obtained results are similar to those obtained by a direct method using road profiles. [source]