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42.
E Forleo-Neto ES Carvalho IC Fuentes MS Precivale LH Forleo CK Farhat 《Canadian Metallurgical Quarterly》1997,15(17-18):1898-1901
The serological response to MMR vaccine was evaluated in 109 9-month-old infants having no history of measles vaccination, and in 98 15-month-old children who had received monocomponent measles immunisation at 9 months. The combined vaccine contained Schwarz, Urabe Am9, and Wistar RA 27/3 live attenuated virus strains. Preimmunisation antibody levels were extremely low for the 9-month-old children, indicating that maternally-transmitted antibodies do not persist at this age. In the case of mumps, preimmunisation antibody levels were significantly higher in the 15-month-old than in the 9-month-old group. A difference between groups in terms of postimmunisation antibody titres was observed only for rubella, with titres being significantly higher in the older group. Seroconversion rates were high in both groups and no serious events attributable to vaccination were observed. The MMR vaccine can thus be administered to children as young as 9 months of age. Evidence for the efficacy of a two-dose schedule, i.e. at 9 and 15 months, is presented. 相似文献
43.
Data compression through a unitary transform is utilized in tomographic microwave diversity image reconstruction in order to reduce the dimensionality and to extract the features in the data space. The unitary compression is derived by minimizing the mean-square error (MSE) and the unitary transform is made of eigenvectors of the data's covariance, regarded as a Karhunen-Loeve transform. Tomographic microwave frequency-swept imaging was developed using a unique target-derived reference technique to access the three dimensional Fourier space of the scatterer and an image reconstruction algorithm based on the projection slice theorem. It is shown that centimeter resolution of a complex object can be preserved even when half of the data set is compressed and that the reconstructed image remains identifiable by a human observer even when 2/3 of the data set is compressed 相似文献
44.
Analytical and experimental studies are presented of frequency-swept microwave imaging of a nondispersive dielectric object satisfying the Born approximation. The retrieved images show from experimental data measured in the frequency range 6-17 GHz are free of the speckle noise that plagues conventional coherent imaging system. The results demonstrate that the microwave imaging system has potential as a cost-effective tool in nondestructive evaluation of dielectric objects 相似文献
45.
The asphaltenes from Saudi Arabian Heavy crude oil residue ( 370°C+ ) were precipitated by adding n-alkane solvents ( n-C5 to n-C 10 ) to the crude oil / residue. 相似文献
46.
Macromorphological and micromorphological seed features of selected taxa of Caesalpiniaceae using light and scanning electron microscopy 总被引:1,自引:0,他引:1
Farhat Ullah Mushtaq Ahmad Muhammad Zafar Asma Jabeen Shazia Sultana Abdul Ghani Muhammad Luqman Moona Nazish Fakhre Alam 《Microscopy research and technique》2019,82(7):1073-1082
Seed micromorphological and macromorphological characteristics of 12 taxa of Caesalpiniaceae from Pakistan have been studied, using light and scanning electron microscopy, to investigate the importance of seed coat features as a taxonomic tool. Great variations have been observed in color, shape, dimension, and seed surface pattern among the different genera of the family. A taxonomic key was prepared for the studied taxa. Six types of seed shapes were observed; circular, elliptical, irregular, oblong, oval, and ovoid. All examined seeds were hard except fragile seeds of Haematoxylom campechianum. Eight types of surface ornamentation have been noticed that include levigate, lugose, papillate, reticulate, reticulate irregular, reticulate regular, rhombus, and rogues. Majority of the taxa has been observed with thick ornamentation wall but thin ornamentation wall has also been recorded in few species. Fracture line of the various patterns was present in all taxa except genus Bauhinia. Three types of texture crudeness; coarse, medium, and fine have been recorded. Both micromorphological and macromorphological characters of seed are very fruitful in identification and classification of Caesalpiniaceae. 相似文献
47.
Pierrick Paillot Wissam Farhat Frédéric Becquart Ruben Vera Corinne Jegat Mohamed Taha 《应用聚合物科学杂志》2019,136(30):47799
The use of silver as an antimicrobial agent has exhibited great interest in recent years. In this research, poly(ethylene-co-vinyl alcohol) (EVOH)–silver acetate-based antimicrobial materials were prepared at high temperature by reactive extrusion. Silver acetates were used without pretreatment. The thermal reaction of silver acetates in the material and their effect on the thermal and mechanical properties of the polymer were investigated as a function of their concentration. The dispersed silver acetate salts within the EVOH matrix have displayed a significant thermal reaction. This reaction of metallic salts was partial when the extrusion temperature was fixed at 190 °C and completed at 230 °C. The antimicrobial agents also had significant effects on the properties of the matrix. Reductions of glass temperature and storage modulus were observed by the analyses. All the variations were dependent on both the concentration of silver acetate and the extrusion parameters. The antimicrobial activity was studied and demonstrated a promising potential to create an antimicrobial material in a one-step solvent free extrusion method. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47799. 相似文献
48.
49.
Mobile Networks and Applications - An effective measure of Key Performance Indicators (KPIs) is of great significance to enhance the capabilities of a decision support system (DSS) of any... 相似文献
50.
S. Waqar H. Zaidi 《Centaurus; international magazine of the history of science and medicine》2021,63(1):17-31
This paper explores the construction of scientists' expertise on international affairs through a study of the rhetoric of U.S. atomic scientists during public and policy‐making debates on the international control of atomic energy between 1945 and 1947. It explores the claims scientists made about the nature of their expertise on issues of diplomacy and international relations and how their expertise was produced and reproduced. The paper shows that scientists were able to successfully project themselves, in the public domain, as experts on political and diplomatic matters related to the atomic. In calling for the international control of atomic energy, scientists constructed their expert knowledge in contrast to, as they portrayed it, the failed expertise of diplomats and political thinkers. In boundary work through their speeches, articles, and government testimonies, scientists drew a line between the political and the scientific, but argued that, as scientist‐citizens, they were able to take their rational thinking from one realm into the other. 相似文献