Increased levels of (class switched) memory B cells in peripheral blood of current smokers

There is increasing evidence that a specific immune response contributes to the pathogenesis of COPD. B-cell follicles are present in lung tissue and increased anti-elastin titers have been found in plasma of COPD patients. Additionally, regulatory T cells (Tregs) have been implicated in its pathogenesis as they control immunological reactions. We hypothesize that the specific immune response in COPD is smoke induced, either by a direct effect of smoking or as a result of smoke-induced lung tissue destruction (i.e. formation of neo-epitopes or auto antigens). Furthermore, we propose that Tregs are involved in the suppression of this smoke-induced specific immune response

Natural Convection Heat Transfer in Enclosures With Multiple Vertical Partitions

of air or vacuum, N 2 = n + IK is the complex refractive index of the lamina material, and 9 2 is the (complex) angle of refraction, which is related to 9 t by Snell's law: N, sin #, = N 2 sin 9 2 . Since r 2l = -r i2 , the reflectance at both interfaces is equal to p = r n rf 2 , where * denotes the complex conjugate. The internal transmittance T is related to the (complex) phase change 6 by r = exp . After carefully examining the transmittance formulae of a lamina, this work shows that the geometric-optics formula may result in a significant error for a highly absorbing medium even in the incoherent limit (when interference effects are negligible). Introduction Consider the transmission of electromagnetic radiation through a lamina with smooth and parallel surfaces. In the incoherent limit when radiation coherence length is much smaller than the thickness of the lamina, the transmittance (or reflectance) may be obtained either by tracing the multiply reflected radiant power fluxes (ray-tracing method) or by separating the power flux at each interface into an outgoing component and an incoming component (net-radiation method), viz. ( where p is the reflectance at the interface and r is the internal transmittance. This formula is also called the geometric-optics formula since it is obtained without considering interference effects. For a plane wave, p equals the square of the absolute value of the complex Fresnel reflection coefficient (i.e., the ratio of the reflected electric field to the incident electric field at the interface). The Fresnel reflection coefficient is (Heavens, 1965) r\ 2 = { cos 9 2 -N 2 cos f?i JVi cos (2) N, cos 0, -N 2 cos 6*2 , . , for s -polarization ,7V, cos 9 t + N 2 cos 9 2 where 9 l is the angle of incidence, /V, = 1 is the refractive index where d is the lamina thickness and X is the wavelength in vacuum. In the coherent limit, the transmittance of a lamina may be obtained from thin-film optics (i.e., wave optics) either by tracing the reflected and transmitted waves (Airy's method) or by separating the electric fields into a forward-propagating component (forward wave) and a backward-propagating component (backward wave), viz. (Heavens, 1965; Analysis and Discussion The power transmittance at the interface between the air (or vacuum) and the medium (lamina) is where (1 + r !2 ) is the Fresnel transmission coefficient. The power transmittance at the second interface between the medium and the air can be obtained by exchanging the subscripts 1 and 2 in Eq. (6). At normal incidence, r 12 = (1 -n -('K)/(1 If both K and Im(r 21 ) are nonzero, T 2 \ =t= 1 -p. As discussed by Journal of Heat Transfer AUGUST 1997, Vol. 119/645 Copyright © 1997 by ASME Zhang The above equation is identical to Eq. (5). However, it is not a simple replacement of (1 -p) 2 in Eq. As an example, suppose the lamina is a LaA10 3 wafer of thickness d = 100 p,m. The optical constants are calculated from the Lorentian dielectric function determined by (1) and the transmittance for a LaA10 3 lamina at wavelengths from 9 to 14 p,m at normal incidence are shown in The difference between the wave-optics formula and the incoherent formula is shown in For a highly absorbing lamina (i.e., r < § 1), multiple reflections may be neglected. The transmittance obtained from Eq. (1), when multiple reflections are negligible, is (1 -pfr. The transmittance calculated from Eq. (8) for T < 1 is where the last expression is for normal incidence only. Eq. Concluding Remarks By inspecting the energy balance at the second interface, this work reveals an implicit assumption associated with Eq. Certain important applications require the determination of transmittance below 10~4. Examples are in the characterization of attenuation filters, bandpass filters, and materials with strong absorption bands Acknowledgments This work has been supported by the University of Florida through a start-up fund and an Interdisciplinary Research Initiative award. / Vol. 119, AUGUST 1997 Transactions of the ASME A. A., 1994, "Modelling of the Reflectance of Silicon," Infrared Physics and Technology, Vol. 35, pp. 701 -708. Frenkel, A" and Zhang, Z. M" 1994, "Broadband High Optical Density Filters in the Infrared," Optics Letters, Vol. 19, pp. 1495-1497 Gentile, T. R., Frenkel, A" Migdall, A. L., and Zhang, Z. M" 1995, "Neutral Density Filter Measurements at the National Institute of Standards and Technology," Spectrophotometry, Luminescence and Colour; Science and Compliance, C. Burgess and D. G. Jones, eds., Elsevier, Amsterdam, The Netherlands, pp. 129-139. Grossman, E. N" and McDonald, D. G" 1995, "Partially Coherent Transmittance of Dielectric Lamellae," Optical Engineering, Vol. 34, pp. 1289-1295. Heavens, O. S., 1965, Optical Properties of Thin Solid Films, Dover Publications, Inc., New York, chap. 4, pp. 46-95. Knittl, Z" 1976, Optical of Thin Films, John Wiley & Sons, Inc., NY, pp. 203-204. Salzberg, B., 1948, "A Note on the Significance of Power Reflection," American Journal of Physics, Vol. 16, pp. 444-446. Siegel, R" and Howell, J. R., 1992, Thermal Radiation Heat Transfer, 3rd ed" Hemisphere Publishing Corp., Washington D.C., chap. 4, p. 120, and chap. 18, pp. 928-930. Yeh, P., 1988, Optical Waves in Layered Media, John Wiley & Sons, Inc., New York, chap. 4, pp. 83-101. Zhang, Z. M., 199

Gamification and Simulation

Gamification and simulation methods are two of the most important components of serious games. In order to create an effective training tool, it is imperative to understand these methods and their relationship to each other. If designed correctly, gamification techniques can build upon simulations to provide an effective training medium, which enhances learning, engagement and motivation in users. This chapter discusses their uses, strengths and weaknesses whilst identifying how to most effectively utilise them in developing serious games

Airway inflammation contributes to health status in COPD:a cross-sectional study

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by irreversible airflow limitation and airway inflammation, accompanied by decreased health status. It is still unknown which factors are responsible for the impaired health status in COPD. We postulated that airway inflammation negatively contributes to health status in COPD. METHODS: In 114 COPD patients (99 male, age: 62 ± 8 yr, 41 [31–55] pack-years, no inhaled or oral corticosteroids, postbronchodilator FEV(1): 63 ± 9% pred, FEV(1)/IVC: 48 ± 9%) we obtained induced sputum and measured health status (St. George's respiratory questionnaire (SGRQ)), postbronchodilator FEV(1), hyperinflation (RV/TLC), and airway hyperresponsiveness to methacholine (PC(20)). Sputum was induced by hypertonic saline and differential cell counts were obtained in 102 patients. RESULTS: Univariate analysis showed that SGRQ total and symptom score were positively associated with % sputum macrophages (r = 0.20, p = 0.05; and r = 0.20, p = 0.04, respectively). Multiple regression analysis confirmed these relationships, providing significant contributions of % sputum macrophages (B = 0.25, p = 0.021) and RV/TLC (B = 0.60, p = 0.002) to SGRQ total score. Furthermore, SGRQ symptom score was associated with % sputum macrophages (B = 0.30, p = 0.03) and RV/TLC (B = 0.48, p = 0.044), whilst SGRQ activity score was associated with % sputum macrophages (B = 0.46, p = 0.002), RV/TLC (B = 0.61, p = 0.015), and PC(20 )(B = -9.3, p = 0.024). Current smoking and FEV(1 )were not significantly associated with health status in the multiple regression analysis. CONCLUSION: We conclude that worse health status in COPD patients is associated with higher inflammatory cell counts in induced sputum. Our findings suggest that airway inflammation and hyperinflation independently contribute to impaired health status in COPD. This may provide a rationale for anti-inflammatory therapy in this disease

Design of a randomized controlled study of a multi-professional and multidimensional intervention targeting frail elderly people

<p>Abstract</p> <p>Background</p> <p>Frail elderly people need an integrated and coordinated care. The two-armed study "Continuum of care for frail elderly people" is a multi-professional and multidimensional intervention for frail community-dwelling elderly people. It was designed to evaluate whether the intervention programme for frail elderly people can reduce the number of visits to hospital, increase satisfaction with health and social care and maintain functional abilities. The implementation process is explored and analysed along with the intervention. In this paper we present the study design, the intervention and the outcome measures as well as the baseline characteristics of the study participants.</p> <p>Methods/design</p> <p>The study is a randomised two-armed controlled trial with follow ups at 3, 6 and 12 months. The study group includes elderly people who sought care at the emergency ward and discharged to their own homes in the community. Inclusion criteria were 80 years and older <it>or </it>65 to 79 years with at least one chronic disease and dependent in at least one activity of daily living. Exclusion criteria were acute severely illness with an immediate need of the assessment and treatment by a physician, severe cognitive impairment and palliative care. The intention was that the study group should comprise a representative sample of frail elderly people at a high risk of future health care consumption. The intervention includes an early geriatric assessment, early family support, a case manager in the community with a multi-professional team and the involvement of the elderly people and their relatives in the planning process.</p> <p>Discussion</p> <p>The design of the study, the randomisation procedure and the protocol meetings were intended to ensure the quality of the study. The implementation of the intervention programme is followed and analysed throughout the whole study, which enables us to generate knowledge on the process of implementing complex interventions. The intervention contributes to early recognition of both the elderly peoples' needs of information, care and rehabilitation and of informal caregivers' need of support and information. This study is expected to show positive effects on frail elderly peoples' health care consumption, functional abilities and satisfaction with health and social care.</p> <p>Trial registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01260493">NCT01260493</a></p

Infertility treatment outcome in sub groups of obese population

<p>Abstract</p> <p>Background</p> <p>Obesity is a common disorder with a negative impact on IVF treatment outcome. It is not clear whether morbidly obese women (BMI >= 35 kg/m2) respond to treatment differently as compared to obese women (BMI = 30–34.9 kg/m2) in IVF. Our aim was to compare the outcome of IVF or ICSI treatments in obese patients to that in morbidly obese patients.</p> <p>Methods</p> <p>This retrospective cohort study was conducted in a tertiary care centre. Patients inclusion criteria were as follows; BMI ≥ 30, age 20–40 years old, first cycle IVF/ICSI treatment with primary infertility and long follicular pituitary down regulation protocol.</p> <p>Results</p> <p>A total of 406 obese patients (group A) and 141 morbidly obese patients (group B) satisfied the inclusion criteria. Average BMI was 32.1 ± 1.38 kg/m2 for group A versus 37.7 ± 2.99 kg/m²for group B. Patient age, cause of infertility, duration of stimulation, fertilization rate, and number of transferred embryos were similar in both groups. Compared to group A, group B had fewer medium size and mature follicles (14 vs. 16), fewer oocytes collected (7 vs. 9) and required higher doses of HMG (46.2 vs. 38.5 amps). There was also a higher cancellation rate in group B (28.3% vs. 19%) and lower clinical pregnancy rate per started cycle (19.9% vs. 28.6%).</p> <p>Conclusion</p> <p>In a homogenous infertile and obese patient population stratified according to their BMI, morbid obesity is associated with unfavorable IVF/ICSI cycle outcome as evidenced by lower pregnancy rates. It is recommended that morbidly obese patients undergo appropriate counseling before the initiation of this expensive and invasive therapy.</p

Development and application of bivariate 2D-EMD for the analysis of instantaneous flow structures and cycle-to-cycle variations of in-cylinder flow

International audienceThe bivariate two dimensional empirical mode decomposition (Bivariate 2D-EMD) is extended to estimate the turbulent fluctuations and to identify cycle-to-cycle variations (CCV) of in-cylinder flow. The Bivariate 2D-EMD is an adaptive approach that is not restricted by statistical convergence criterion, hence it can be used for analyzing the nonlinear and non-stationary phenomena. The methodology is applied to a high-speed PIV dataset that measures the velocity field within the tumble symmetry plane of an optically accessible engine. The instantaneous velocity field is decomposed into a finite number of 2D spatial modes. Based on energy considerations, the in-cylinder flow large-scale organized motion is separated from turbulent fluctuations. This study is focused on the second half of the compression stroke. For most of the cycles, the maximum of turbulent fluctuations is located between 50 and 30 crank angle degrees before top dead center (TDC). In regards to the phase-averaged velocity field, the contribution of CCV to the fluctuating kinetic energy is approximately 55% near TDC

Coupling of CFD and semiempirical methods for designing three-phase condensate separator: case study and experimental validation

This study presents an approach to determine the dimensions of three-phase separators. First, we designed different vessel configurations based on the fluid properties of an Iranian gas condensate field. We then used a comprehensive computational fluid dynamic (CFD) method for analyzing the three-phase separation phenomena. For simulation purposes, the combined volume of fluid–discrete particle method (DPM) approach was used. The discrete random walk (DRW) model was used to include the effect of arbitrary particle movement due to variations caused by turbulence. In addition, the comparison of experimental and simulated results was generated using different turbulence models, i.e., standard k–ε, standard k–ω, and Reynolds stress model. The results of numerical calculations in terms of fluid profiles, separation performance and DPM particle behavior were used to choose the optimum vessel configuration. No difference between the dimensions of the optimum vessel and the existing separator was found. Also, simulation data were compared with experimental data pertaining to a similar existing separator. A reasonable agreement between the results of numerical calculation and experimental data was observed. These results showed that the used CFD model is well capable of investigating the performance of a three-phase separator

The changing role of china in the global illegal cigarette trade

This study explores the history of the illegal production, distribution, and smuggling of cigarettes in mainland China. Data were obtained from a content analysis of 931 media reports retrieved from LexisNexis for the time period 1975 until 2010, and from other open sources. The illegal cigarette trade first emerged in the form of violations of state tobacco monopoly regulations. In the course of the restructuring of the legal tobacco sector, which occurred under external political pressure to open the Chinese market to foreign competition, an illegal cigarette industry emerged which at first primarily produced fake Chinese brand cigarettes for the domestic black market. At the same time, China became a destination country for smuggled genuine Western brand cigarettes. It was only after effective crackdowns against cigarette smuggling and domestic distribution channels in the late 1990s that the Chinese illegal cigarette industry shifted to exporting large numbers of counterfeit Western brand cigarettes to black markets abroad. China’s current role as a leading supplier of counterfeit cigarettes is a result of the contradictions of the economic reform process and of external licit and illicit forces that worked toward opening up the Chinese tobacco sector to the outside world

Smoking cessation and bronchial epithelial remodelling in COPD: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Chronic Obstructive Pulmonary Disease (COPD) is associated with bronchial epithelial changes, including squamous cell metaplasia and goblet cell hyperplasia. These features are partially attributed to activation of the epidermal growth factor receptor (EGFR). Whereas smoking cessation reduces respiratory symptoms and lung function decline in COPD, inflammation persists. We determined epithelial proliferation and composition in bronchial biopsies from current and ex-smokers with COPD, and its relation to duration of smoking cessation.</p> <p>Methods</p> <p>114 COPD patients were studied cross-sectionally: 99 males/15 females, age 62 ± 8 years, median 42 pack-years, no corticosteroids, current (n = 72) or ex-smokers (n = 42, median cessation duration 3.5 years), postbronchodilator FEV₁63 ± 9% predicted. Squamous cell metaplasia (%), goblet cell (PAS/Alcian Blue⁺) area (%), proliferating (Ki-67⁺) cell numbers (/mm basement membrane), and EGFR expression (%) were measured in intact epithelium of bronchial biopsies.</p> <p>Results</p> <p>Ex-smokers with COPD had significantly less epithelial squamous cell metaplasia, proliferating cell numbers, and a trend towards reduced goblet cell area than current smokers with COPD (p = 0.025, p = 0.001, p = 0.081, respectively), but no significant difference in EGFR expression. Epithelial features were not different between short-term quitters (<3.5 years) and current smokers. Long-term quitters (≥3.5 years) had less goblet cell area than both current smokers and short-term quitters (medians: 7.9% vs. 14.4%, p = 0.005; 7.9% vs. 13.5%, p = 0.008; respectively), and less proliferating cell numbers than current smokers (2.8% vs. 18.6%, p < 0.001).</p> <p>Conclusion</p> <p>Ex-smokers with COPD had less bronchial epithelial remodelling than current smokers, which was only observed after long-term smoking cessation (>3.5 years).</p> <p>Trial registration</p> <p>NCT00158847</p