Central Limit Theorem for truncated heavy tailed Banach valued random vectors

In this paper the question of the extent to which truncated heavy tailed random vectors, taking values in a Banach space, retain the characteristic features of heavy tailed random vectors, is answered from the point of view of the central limit theorem.

Nonlinear measures of respiration: Respiratory irregularity and increased chaos of respiration in patients with panic disorder

Background. Respiratory irregularity has been previously reported in patients with panic disorder using time domain measures. However, the respiratory signal is not entirely linear and a few previous studies used approximate entropy (APEN), a measure of regularity of time series. We have been studying APEN and other nonlinear measures including a measure of chaos, the largest Lyapunov exponent (LLE) of heart rate time series, in some detail. In this study, we used these measures of respiration to compare normal controls (n = 18) and patients with panic disorder (n = 22) in addition to the traditional time domain measures of respiratory rate and tidal volume. Methods: Respiratory signal was obtained by the Respitrace system using a thoracic and an abdominal belt, which was digitized at 500 Hz. Later, the time series were constructed at 4 Hz, as the highest frequency in this signal is limited to 0.5 Hz. We used 256 s of data (1,024 points) during supine and standing postures under normal breathing and controlled breathing at 12 breaths/min. Results: APEN was significantly higher in patients in standing posture during normal as well as controlled breathing (p = 0.002 and 0.02, respectively). LLE was also significantly higher in standing posture during normal breathing (p = 0.009). Similarly, the time domain measures of standard deviations and the coefficient of variation (COV) of tidal volume (TV) were significantly higher in the patient group (p = 0.02 and 0.004, respectively). The frequency of sighs was also higher in the patient group in standing posture (p = 0.02). In standing posture, LLE (p < 0.05) as well as APEN (p < 0.01) contributed significantly toward the separation of the two groups over and beyond the linear measure, i.e. the COV of TV. Conclusion: These findings support the previously described respiratory irregularity in patients with panic disorder and also illustrate the utility of nonlinear measures such as APEN and LLE as additional measures toward a better understanding of the abnormalities of respiratory physiology in similar patient populations as the correlation between LLE, APEN and some of the time domain measures only explained up to 50-60% of the variation. Copyright (C) 2002 S. Karger AG, Basel.

The central region of meso-3,4-diphenylhexane-2,5-dione

As with 1,2-diphenylethane (dpe), X-ray crystallographic methods measure the central bond in meso-3,4-diphenylhexane-2,5-done (dphd) as significantly shorter than normal for an sp(3)-sp(3) bond. The same methods measure the benzylic (ethane C-Ph) bonds in dphd as unusually long for sp(3)-sp(2) liaisons. Torsional motions of the phenyl rings about the C-Ph bonds have been proposed as the artifacts behind the result of a 'short' central bond in dpe. While a similar explanation can, presumably, hold for the even 'shorter' central bond in dphd, it cannot account for the 'long' C-Ph bonds. The phenyl groups, departing much from regular hexagonal shape, adopt highly skewed conformations with respect to the plane constituted by the four central atoms. It is thought that-the thermal motions of the phenyl rings, conditioned by the potential wells in which they are ensconced in the unit cell, are largely libratory around their normal axes. In what appears to be a straightforward explanation under the 'rigid-body' concept, it appears that these libratory motions of the phenyl rings, that account, at the same time, for the 'short' central bond, are the artifacts behind the 'long' measurement of the C-Ph bonds. These motions could be superimposed on torsional motions analogous to those proposed in the case of dpe. An inspection of the ORTEP diagram from the 298 K data on dphd clearly suggests these possibilities. Supportive evidence for these qualitative explanations from an analysis of the differences between the mean square displacements of C(1) and C(7)/C(1a) and C(7a) based on the 'rigid-body model' is discussed. (C) 2002 Elsevier Science B.V. All rights reserved.

Landslide susceptibility mapping in the downstream region of Sharavathi river basin, Central Western Ghats

Landslides are hazards encountered during monsoon in undulating terrains of Western Ghats causing geomorphic make over of earth surface resulting in significant damages to life and property. An attempt is made in this paper to identify landslides susceptibility regions in the Sharavathi river basin downstream using frequency ratio method based on the field investigations during July- November 2007. In this regard, base layers of spatial data such as topography, land cover, geology and soil were considered. This is supplemented with the field investigations of landslides. Factors that influence landslide were extracted from the spatial database. The probabilistic model -frequency ratio is computed based on these factors. Landslide susceptibility indices were computed and grouped into five classes. Validation of LHS, showed an accuracy of 89% as 25 of the 28 regions tallied with the field condition of highly vulnerable landslide regions. The landslide susceptible map generated for the downstream would be useful for the district officials to implement appropriate mitigation measures to reduce hazards.

Influences of the springtime northern Indian biomass burning over the central Himalayas

The influences of the springtime northern Indian biomass burning are shown for the first time over the central Himalayas by using three years (2007-2009) of surface and space based observations along with a radiative transfer model. Near-surface ozone, black carbon (BC), spectral aerosol optical depths (AODs) and the meteorological parameters are measured at a high altitude site Nainital (29.37 degrees N, 79.45 degrees E, 1958 m amsl) located in the central Himalayas. The satellite observations include the MODIS derived fire counts and AOD (0.55 mu m), and OMI derived tropospheric column NO(2), ultraviolet aerosol index and single scattering albedo. MODIS fire counts and BC observations are used to identify the fire-impacted periods (372 h during 2007-2009) and hence the induced enhancements in surface BC, AOD (0.5 mu m) and ozone are estimated to be 1802 ng m(-3) (similar to 145%), 0.3 (similar to 150%) and 19 ppbv (similar to 34%) respectively. Large enhancements (53-100%) are also seen in the satellite derived parameters over a 2 degrees x 2 degrees region around Nainital. The present analysis highlights the northern Indian biomass burning induced cooling at the surface (-27 W m(-2)) and top of the atmosphere (-8 W m(-2)) in the lesser polluted high altitude regions of the central Himalayas. This cooling leads to an additional atmospheric warming of 19 W m(-2) and increases the lower atmospheric heating rate by 0.8 K day(-1). These biomass burning induced changes over the central Himalayan atmosphere during spring may also lead to enhanced short-wave absorption above clouds and might have an impact on the monsoonal rainfall.

Modelling and classification of respiratory volume wavefourms

A technique is proposed for classifying respiratory volume waveforms(RVW) into normal and abnormal categories of respiratory pathways. The proposed method transforms the temporal sequence into frequency domain by using an orthogonal transform, namely discrete cosine transform (DCT) and the transformed signal is pole-zero modelled. A Bayes classifier using model pole angles as the feature vector performed satisfactorily when a limited number of RVWs recorded under deep and rapid (DR) manoeuvre are classified.

Spatio-temporal landscape modelling for natural hazard vulnerability analysis in select watersheds of Central Western Ghats

Natural hazards such as landslides are triggered by numerous factors such as ground movements, rock falls, slope failure, debris flows, slope instability, etc. Changes in slope stability happen due to human intervention, anthropogenic activities, change in soil structure, loss or absence of vegetation (changes in land cover), etc. Loss of vegetation happens when the forest is fragmented due to anthropogenic activities. Hence land cover mapping with forest fragmentation can provide vital information for visualising the regions that require immediate attention from slope stability aspects. The main objective of this paper is to understand the rate of change in forest landscape from 1973 to 2004 through multi-sensor remote sensing data analysis. The forest fragmentation index presented here is based on temporal land use information and forest fragmentation model, in which the forest pixels are classified as patch, transitional, edge, perforated, and interior, that give a measure of forest continuity. The analysis carried out for five prominent watersheds of Uttara Kannada district– Aganashini, Bedthi, Kali, Sharavathi and Venkatpura revealed that interior forest is continuously decreasing while patch, transitional, edge and perforated forest show increasing trend. The effect of forest fragmentation on landslide occurrence was visualised by overlaying the landslide occurrence points on classified image and forest fragmentation map. The increasing patch and transitional forest on hill slopes are the areas prone to landslides, evident from the field verification, indicating that deforestation is a major triggering factor for landslides. This emphasises the need for immediate conservation measures for sustainable management of the landscape. Quantifying and describing land use - land cover change and fragmentation is crucial for assessing the effect of land management policies and environmental protection decisions.

Radiative effects of elevated aerosol layer in Central Himalayas

Systematic observations of light detection and ranging (LIDAR) to detect elevated aerosol layer were carried out at Manora Peak (29.4 degrees N, 79.5 degrees E, similar to 1960 m a.s.l), Nainital, in the Central Himalayas during January-May 2008. In spite of being a remote, high-altitude site, an elevated aerosol layer is observed quite frequently in the altitude range of 2460-4460 m a.s.l with a width of similar to 2 km during the observation period. We compare these profiles with the vertical profiles observed over Gadanki (13.5 degrees N, 79.2 degrees E, similar to 370 m a.s.l), a tropical station, where no such elevated aerosol layer was found. Further, there is a steady increase in aerosol optical depth (AOD) from January (winter) to May (summer) from 0.043 to 0.742, respectively, at Manora Peak, indicating aerosol loading in the atmosphere. Our observations show north-westerly winds indicating the convective lifting of aerosols from far-off regions followed by horizontal long-range transport. The presence of strongly absorbing and scattering aerosols in the elevated layer resulted in a relatively large diurnal mean aerosol surface radiative forcing efficiency (forcing per unit optical depth) of about -65 and -63 W m(-2) and the corresponding mean reduction in the observed net solar flux at the surface (cooling effect) is as high as -22 and -30 W m(-2). The reduction of radiation will heat the lower atmosphere by redistributing the radiation with heating rate of 1.13 and 1.31 K day(-1) for April and May 2008, respectively, in the lower atmosphere.

Hypoxia-Mediated Impairment of the Mitochondrial Respiratory Chain Inhibits the Bactericidal Activity of Macrophages

In infected tissues oxygen tensions are low. As innate immune cells have to operate under these conditions, we analyzed the ability of macrophages (M phi) to kill Escherichia coli or Staphylococcus aureus in a hypoxic microenvironment. Oxygen restriction did not promote intracellular bacterial growth but did impair the bactericidal activity of the host cells against both pathogens. This correlated with a decreased production of reactive oxygen intermediates (ROI) and reactive nitrogen intermediates. Experiments with phagocyte NADPH oxidase (PHOX) and inducible NO synthase (NOS2) double-deficient M phi revealed that in E. coli- or S. aureus-infected cells the reduced antibacterial activity during hypoxia was either entirely or partially independent of the diminished PHOX and NOS2 activity. Hypoxia impaired the mitochondrial activity of infected M phi. Inhibition of the mitochondrial respiratory chain activity during normoxia (using rotenone or antimycin A) completely or partially mimicked the defective antibacterial activity observed in hypoxic E. coli-or S. aureus-infected wild-type M phi, respectively. Accordingly, inhibition of the respiratory chain of S. aureus-infected, normoxic PHOX-/- NOS2(-/-) M phi further raised the bacterial burden of the cells, which reached the level measured in hypoxic PHOX-/- NOS2(-/-) M phi cultures. Our data demonstrate that the reduced killing of S. aureus or E. coli during hypoxia is not simply due to a lack of PHOX and NOS2 activity but partially or completely results from an impaired mitochondrial antibacterial effector function. Since pharmacological inhibition of the respiratory chain raised the generation of ROI but nevertheless phenocopied the effect of hypoxia, ROI can be excluded as the mechanism underlying the antimicrobial activity of mitochondria.