1,771 research outputs found
Logarithmic Correction to BMSFT Entanglement Entropy
Using Rindler method we derive the logarithmic correction to the entanglement
entropy of a two dimensional BMS-invariant field theory (BMSFT). In particular,
we present a general formula for extraction of the logarithmic corrections to
both the thermal and the entanglement entropies. We also present a CFT formula
related to the logarithmic correction of the BTZ inner horizon entropy which
results in our formula after taking appropriate limit.Comment: 15 pages, V2: Minor corrections, V3: Published versio
Pulmonary manifestations in smoking-related diseases : clinical studies with emphasis on chronic obstructive pulmonary disease and rheumatoid arthritis
Smoking is a risk factor for a number of diseases including chronic obstructive
pulmonary disease (COPD) and rheumatoid arthritis (RA). Cigarette smoke initiates
an inflammatory response which leads to structural changes in the airways and in
the lung parenchyma. The present work was undertaken in order to shed light on
pulmonary manifestations of two common smoking-related diseases, COPD and RA.
A retrospective review on bronchoalveolar lavage (BAL) constituents, encompassing
132 smokers with normal lung function and 44 ex-smokers, was performed. Two
hundred and ninety- five neversmokers served as reference group. The median (5-95
percentile) cell concentration in smokers were 382.1 (189.7-864.3) X 106 /L which
was higher compared to the neversmokers. The majority of cells were alveolar
macrophages (median 96.7%; range 73.2-99.6%, lymphocytes (2%; range 0.2-26%) and
neutrophils (0.6%; range 0-6%). Cell concentration was positively correlated to
cumulative smoking history.
One hundred and five patients with newly-diagnosed RA, (70% ACPA+), underwent high
resolution computer tomography (HRCT) examination and
a sub group of 23 patients also performed bronchoscopy and BAL. A group of 43
non-diseased smokers and never smokers were examined as control. Parenchymal lung
abnormality on HRCT was found in 63% of ACPA+ compared to 37% ACPA- RA patients,
30% control regardless of smoking status. The level of ACPA was higher in BAL
fluid than sera in ACPA+ RA patients.
Forty smokers with normal lung function,(mean 35 pack-years), 40 healthy never-smokers,
and 40 COPD-patients of GOLD,I-II, (38 PY), performed HRCT. In addition BAL was performed.
Percentage of pixelsbetween -750- -900 HU (%HDS) was calculated. Lung density was increased
in smokers (44.0% ± 5.8%) compared to never smokers (38.3 ± 5.8%), p<0.001. Cell
concentration in BAL was positively correlated to lung density in smokers (r=0.50,
p<0.001). Females had denser lungs than males.
Regional air trapping was assessed
on expiatory HRCT on 40 never-smokers, 40 smokers and 40 COPD-patients. Emphysema,
micronoduli, bronchial wall thickening was determined on inspiratory HRCT. Air
trapping index (AI) was quantified as the ratio of mean lung attenuation at
expiration and inspiration. Regional air trapping was present in 63% of smokers
and 45% of never smokers. Smokers with visible regional air trapping had an AI of
0.81, while smokers without visible air trapping had an AI of 0.91. A negative
correlation between AI and neutrophils in BAL was observed. Smokers with regional
air trapping had better lung function and less emphysema compared to smokers
without.
We demonstrate inflammatory and structural changes in the lungs in
smokers by means of HRCT and BAL. These changes are apparent even before clinical
symptoms occur. The studies highlight the heterogeneity in smoking-related
diseases which may be of importance in terms of disease progression and patient
phenotypes
Robust H∞ filter design for uncertain linear systems over network with network-induced delays and output quantization
This paper investigates a convex optimization approach to the problem of robust H∞ filtering for uncertain linear systems connected over a common digital communication network. We consider the case where quantizers are static and the parameter uncertainties are norm bounded. Firstly, we propose a new model to investigate the effect of both the output quantization levels and the network conditions. Secondly, by introducing a descriptor technique, using Lyapunov- Krasovskii functional and a suitable change of variables, new required sufficient conditions are established in terms of delay-dependent linear matrix inequalities (LMIs) for the existence of the desired network-based quantized filters with simultaneous consideration of network induced delays and measurement quantization. The explicit expression of the filters is derived to satisfy both asymptotic stability and a prescribed level of disturbance attenuation for all admissible norm bounded uncertainties. © 2009 Norwegian Society of Automatic Control
Kinetics of hydrogen evolution reaction on Ni-Me-P electrodes
Hydrogen, a wholly non-polluting and renewable fuel, may be obtained by the electrocatalytic hydrogen evolution reaction (HER). Electrocatalytic hydrogen production calls for efficient and durable electrodes by finding the origin of the electrocatalytic activity, and improving the properties. The candidate materials for cathodes are limited. Those that have high surface area suffer from low physical stability and deterioration in long-term operation. If physical stability is improved the activity is decreased. When both properties are improved the production expense is increased. The main purpose of this study is to prepare new electrode materials and study their activity and reaction mechanism for the HER. Three categories of the electrodes of nickel phosphorous family were studied, Ni-P, Ni-Mo-P, and Ni-Zn-P. Ni-P materials are very stable in alkaline solutions. Their stability is better than Ni. Phosphorous is not removed by means of leaching the electrodes in HF, alkaline solutions, heating, and/or oxidation to produce a rough surface. Electrodes prepared at low current densities and temperature were active for the HER due to increase in the surface roughness. The most active Ni-P electrode prepared in this study had a surface roughness of 10[subscript 3] XRD patterns of Ni-P electrodes have amorphous structure. After heating at 400 [degree Celsius] the structure of electrodes changed to crystalline with domination of Ni[subscript 3]P phase (for high phosphorous content electrodes) or Ni[subscript 3]P and Ni (for low phosphorous content electrodes). Ni-Mo-P electrodes were prepared by"multi-step" electrodeposition. The activity of the electrodes was increased through increase in surface roughness as well as intrinsic activity. Cycling of the electrodes between the HER and oxygen evolution reaction (OER) deactivated them. Mo was mostly dissolved during electrooxidation of these materials. Ni-Zn-P electrodes were prepared by subsequent electrodeposition of Ni, Ni-P, and Ni-Zn-P. The top-most layer was obtained by gradual addition of zinc to the plating bath. After leaching the electrodes in 30% KOH, about 80% of Zn was removed leading to a porous surface with a large area with excellent stability. Those prepared at high current densities are the most active ones. They are characterized by low Tafel slopes and large surface area with roughness factor of 10[subscript 4]. Electrochemical impedance spectroscopy (EIS) and steady-state polarization are mainly used to explain activity of the electrodes using real surface area. A new technique for the surface roughness determination i.e.,"CO molecular probe" was developed. Ni-Zn-P porous electrode surface roughness was measured by the EIS and compared with results from surface oxidation, cyclic voltammetry (cv), ratio of the polarization current densities, and CO molecular probe showing good agreement with those obtained by the EIS. Besides, the results show that dissolved CO in NaOH can be oxidized on Ni and Ni-Zn-P electrodes. This is a new observation of CO behavior on nickel based electrodes."--Résumé abrégé par UM
A Semiactive Vibration Control Design for Suspension Systems with Mr Dampers
Published version of a chapter published in the book: Vibration Analysis and Control - New Trends and Developments. Also available from the publisher at: http://www.intechopen.com/source/pdfs/17688/InTech-A_semiactive_vibration_control_design_for_suspension_systems_with_mr_dampers.pdf. O
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