Streptococcus pneumoniae colonisation in children and adolescents with asthma: impact of the heptavalent pneumococcal conjugate vaccine and evaluation of potential effect of thirteen-valent pneumococcal conjugate vaccine.

Background: The main aim of this study was to evaluate Streptococcus pneumoniae carriage in a group of school-aged children and adolescents with asthma because these results might indicate the theoretical risk of invasive pneumococcal disease (IPD) of such patients and the potential protective efficacy of the 13-valent pneumococcal conjugate vaccine (PCV13). Methods: Oropharyngeal samples were obtained from 423 children with documented asthma (300 males, 70.9%), and tested for the autolysin-A-encoding (lytA) and the wzg (cpsA) gene of S. pneumoniae by means of real-time polymerase chain reaction. Results: S. pneumoniae was identified in the swabs of 192 subjects (45.4%): 48.4% of whom were aged <10years, 46.9% aged 10-14 years, and 4.7% aged ≥15years (p < 0.001). Carriage was significantly less frequent among the children who had received recent antibiotic therapy (odds ratio [OR 0.41]; 95% confidence interval [95% CI] 0.22-0.76). Multivariate analyses showed no association between carriage and vaccination status, with ORs of 1.05 (95% CI 0.70-1.58) for carriers of any pneumococcal serotype, 1.08 (95% CI 0.72-1.62) for carriers of any of the serotypes included in 7-valent pneumococcal conjugate vaccine (PCV7), and 0.76 (95% CI 0.45-1.28) for carriers of any of the six additional serotypes of PCV13. Serotypes 19F, 4 and 9V were the most frequently identified serotypes in vaccinated subjects. Conclusions: These results showed that carriage of S. pneumoniae is relatively common in all school-aged children and adolescents with asthma, regardless of the severity of disease and the administration of PCV7 in the first years of life. This highlights the problem of the duration of the protection against colonisation provided by pneumococcal conjugate vaccine, and the importance of re-colonization by the same pneumococcal serotypes included in the previously used vaccine

Development And Experimental Validation Of A Numerical Thermal Model For The Evaluation Of The Depth Of Laser Treated Zone In The Laser Transformation Hardening Process

The aim of this work is to develop a mathematical model to predict the depth of laser treated zone in the LTH process. The Fourier equation of heat conduction was solved by using the Finite Difference Method in cylindrical coordinates in order to study the temperature distribution produced in a workpiece and hence to obtain the depth to which hardening occurs. The theoretical simulations were compared with results produced experimentally by a CO2 laser operating in continuous wave, showing good agreement.423-425707712Damborenea, J., (1998) Surface Coat. Tech., 100-101, pp. 377-382Ion, J.C., Shercliff, H.R., Ashby, M.F., (1992) Acta Metall. Mater., 40, pp. 1539-1551Monson, P.J.E., Steen, W.M., (1990) Surface Eng., 6, pp. 185-193Ashby, M.F., Easterling, K.E., (1984) Acta Metall. Mater., 32, pp. 1935-1948Woo, H.G., Cho, H.S., (1998) Surface Coat. Tech., 102, pp. 205-217Bokota, A., Iskierka, S., (1996) Acta Mater., 44, pp. 445-450Kumar, S., Meech, J.A., Samarasekera, I.V., Brimacombe, J.K., (1993) I&SM, pp. 29-36Filipic, B., Sarler, B., (1998) Proceedings os the 6th European Congress on Intelligent Techniques and Soft Computing, , (Aachen, Germany)Cheung, N., Ierardi, M.C.F., Garcia, A., Vilar, R., (2000) Lasers Eng., 10, pp. 275-291Cheung, N., Garcia, A., (2001) Eng. Appl. Artificial Intelligence, 14, pp. 229-238Merling, J., Renard, C., Bignonnet, A., Li, J., (1992) Matériaux et Techniques Été, 92, pp. 6-8Putatunda, S.K., Nambiar, M., Clark, N., (1997) Surface Eng., 13, pp. 407-414Shiue, R.K., Chen, C., (1991) Scripta Metall. Mater., 25, pp. 1889-1894Shiue, R.K., Chen, C., (1992) Metall. Trans. A, 23, pp. 163-170Yang, L.J., Jana, S., Tam, S.C., (1990) J. Mater. Process. Tech., 23, pp. 133-147Yang, L.J., Jana, S., Tam, S.C., Lim, L.E.N., (1994) Mater. Manuf. Process, 9, p. 475Reti, T., Bagyinski, G., Felde, I., Verö, B., Bell, T., (1999) Comp. Mater. Sci., 15, p. 101Ruiz, J., Fernández, B.J., Ma. Belló, J., (1990) Key Eng. Mat., 46-47, pp. 161-174Shang, H.M., (1990) J. Mater. Process. Tech., 23, pp. 65-72Davis, M., Kapadia, P., Dowden, J., Steen, W.M., Courtney, C.H.G., (1986) J. Appl. Phys. D, 19, pp. 1981-1996Zubair, S.M., Aslam Chaudhry, M., (1996) Int J Heat Mass. Tran., 39, pp. 3067-3074Incropera, F.P., Dewitt, D.P., (1990) Fundamentals of Heat and Mass Transfer, , (John Wiley & Sons, New York)Jansson, B., Rolfson, M., Thuvander, A., Melander, A., Wullimann, C., (1991) Materials Science and Technology, 7, pp. 118-127Ruddle, R.W., (1957) The Solidification of Castings, , (Institute of Metals, Series NO. 7)Atkins, M., (1980) Atlas of Continuous Cooling Transformation Diagrams for Engineering Steels, , (British Steel Corp., ASM, Metals Park)Dardel, Y., (1964) Edition de la Revue de Metalurgi

Numerical Simulation And Experimental Analysis Of Laser Surface Remelting Of Aisi 420 Stainless Steel Samples

The aim of this work is to develop a heat transfer mathematical model based on the finite difference method in order to simulate temperature fields in the laser surface remelting process. Convective heat transfer in the remelted pool is taken into account by using the effective thermal conductivity approach. Experiments of laser surface remelting of AISI 420 stainless steel samples were carried out in the present investigation, and numerical simulations were applied for the laser machine operating parameters. The work also encompasses the analysis of microstructural and microhardness variations throughout the resulting treated and unmolten zones. © 2009 Trans Tech Publications, Switzerland.59265268Watkins, K.G., McMahon, M.A., Steen, W.M., (1997) Mater. Sci. Eng, A231, p. 55Cheung, N., Ierardi, M.C.F., Garcia, A., Vilar, R., (2000) Lasers Eng, 10, p. 275Hsu, S.C., Kou, S., Mehrabian, R., (1980) Metall Trans B, 11, p. 29Sekhar, J.A., Kou, S., Mehrabian, R., (1984) Metall Trans A, 14, p. 1169Chan, C., Mazumder, J., Chen, M.M., (1984) Metall Trans A, 15, p. 2175Kou, S., Wang, Y.H., (1986) Metall Trans A, 17, p. 2265Hoadley, A.F.A., Rappaz, M., Zimmerman, M., (1991) Metall Trans B, 22, p. 101Davies, G.J., Laki, R.S., Saucedo, I.G., Shin, Y.K., (1984) Perspectives in Metallurgical Development, p. 123. , University of Sheffield, SheffieldApps, R.L., Milner, D.R., (1963) British Welding Journal, p. 348F. P. Incropera, D. P. Dewitt Fundamentals of Heat and Mass Transfer (John Wiley & Sons, New York 1990)R. W. Ruddle, The Solidification of Castings. (Institute of Metals, Series No. 7 1957)Pehlke, R.D., Jeyarajan, A., Wada, H., (1980) Summary of thermal properties for casting alloys and mold materials, , Ann Arbor, University of MichiganGill, S.C., Zimmermann, M., Kurz, W., (1992) Acta Metall Mater, 40, p. 289

99Tcm-MIBI uptake in green plants.

Uptake of 99mTcm-sestamibi by biological structures depends on delivery and concentration by electrochemical gradients through the biological membranes and can be simply studied using a green plant model in which photosynthesis tightly modulates water and solute regional flow. Photosynthesis creates electrochemical gradients inside chloroplasts and mitochondria. Moreover, it is the driving force for the movement of water and solutes through induction of pore opening which causes capture of CO2 and loss of water vapour. Thus osmotic pressure increases thereby drawing water from the roots. Hypoestes sanguinolenta was used as an experimental model. This plant displays green zones (with several chloroplasts) and red zones (where they are absent). To detect the uptake differences between these zones we used a new, high-resolution gamma camera. Our results show that (a) 99mTcm-sestamibi is actively transported with water and ions by xylem to leaves where it may diffuse at cellular levels; (b) activation of photosynthesis by light strongly influences the total uptake and the selective compartmentation in green zones; and (c) the green plant's particular physiology tremendously enhances the differences between 99Tcm-sestamibi and 201Tl uptake. We suggest that viable cells, able to create and maintain electrochemical gradients, selectively take up 99Tcm-sestamibi