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41.
This study examined if the aversive properties of morphine, the aversive properties of morphine withdrawal, and the discriminative properties of morphine are mediated by common neurobiological substrates. Lesions of the lateral parabrachial nucleus, which blocked the aversive properties of morphine in the conditioned taste aversion paradigm, also blocked the acquisition of conditioned place aversions to environments paired with the aversive properties of morphine withdrawal in morphine-dependent rats. When morphine and saline were used as cues in a discrimination task, however, both sham-operated and lesioned rats were able to solve the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
43.
Etemad Elham Samavi Shadrokh Reza Soroushmehr S. M. Karimi Nader Etemad Mohammad Shirani Shahram Najarian Kayvan 《Multimedia Tools and Applications》2018,77(2):2033-2055
Multimedia Tools and Applications - Nowadays, due to widespread usage of the Internet, digital contents are distributed quickly and inexpensively throughout the world. Watermarking techniques can... 相似文献
44.
Sallis James F.; Nader Philip R.; Broyles Shelia L.; Berry Charles C.; Elder John P.; McKenzie Thomas L.; Nelson Julie A. 《Canadian Metallurgical Quarterly》1993,12(5):390
22 potential correlates of children's physical activity were examined. 201 Mexican-American and 146 Anglo-American families with 4-yr-old children were studied. Children's physical activity was directly observed in the evening at home on 4 visits for 1 hr each time. Anglo-American children and male children were found to be more active. Demographic variables explained 11% of the variance in children's physical activity. After adjusting for demographics, 3 children's variables and 6 social-family variables did not account for significantly more variance. Five environmental variables accounted for 11% additional variance. Variables observed concurrently with physical activity, such as time spent outdoors and prompts to be active, were highly associated with children's physical activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Hydraulic jumps in density currents are technically referred to density jumps. These jumps significantly influence the dynamic and quality characteristics of the gravity currents. The density jump is studied theoretically and experimentally in this study by considering the bed roughness. Experiments were performed in a rectangular laboratory flume (0.4 m width; 0.9 m depth; 8.3 m length). Four rough beds comprised of closely packed gravel particles glued onto the horizontal part of the bed were examined. For both smooth and rough beds, a simple relationship was obtained for estimating the conjugate depth ratio as a function of the relative roughness and the upstream densimetric Froude number. The conjugate depth ratio was found to decrease with increasing relative roughness. The results also indicated that, if the entrainment ratio is specified, the minimum value of the upstream densimetric Froude number increases with increasing relative bed roughness. An equation for calculating the maximum possible value of the relative roughness was also determined. The spatial development of the density current for smooth beds was analysed in both super‐critical and sub‐critical flow regimes. Good similarity collapses of velocity and concentration profiles were obtained for the super‐critical section just upstream of the jump. The concentration distributions located just downstream of the jump, however, exhibited a large scattering of measured data, especially near the bed. It was found that this scattering decreases with the distance from the end of the jump. The results of the experimental runs also indicated that, at a distance about nine times the post‐jump current thickness from the end of the jump, the non‐dimensional vertical profile of mean velocity has a shape similar to that at the pre‐jump section. A new reliable relationship was also proposed for calculating the local velocity inside both the wall and jet regions. 相似文献
46.
Nader Ebrahimi 《Sequential Analysis》2013,32(3):213-227
Exact reliability analysis for complex repairable systems are usually difficult because of the complicated failure process that can result from repair policy. A common approach in practice is to use a simplified process such as the Power Law process which, although not exact, yields useful practical results. In this paper we consider the problem of determining a stopping time when estimating parameters of a Power Law process. The Bayes method is used in order to obtain an optimal time. 相似文献
47.
Optical measurements are used to investigate the crystalline quality and the stress in thin AlN layers; these thin films are grown on cubic silicon carbide layers which are in turn grown on silicon (111) substrates. Different Ge amounts were deposited at the silicon substrate in order to reduce the lattice parameters mismatch between Si and SiC grown layers. The residual stress of the hexagonal AlN layers is derived from the phonon frequency shifts of the E1(TO) phonon mode. The crystalline quality of AlN films is investigated by considering the intensity of E1(TO) mode of the 2H-AlN and its full width of the half maximum (FWHM). Ge deposition at low temperature 325 °C, before the carbonization process leads to an improved crystalline quality and a reduced residual stress in the AlN/SiC/Si heterostructures. The best crystalline quality and the lowest stress value are found in the case where 1ML Ge amount was predeposited. The E1(TO) mode, phonon frequency shifts-down by 3 cm? 1/GPa with respect to an unstrained layer. The obtained values for the phonon deformation are in reasonable agreement with theoretical calculations. 相似文献
48.
Amal Amin Heba Kandil Mohamed Nader Ismail Nergis Makal Charles N. Moorefield George R. Newkome 《Polymer Engineering and Science》2014,54(11):2669-2675
An adamantane‐based atom transfer radical initiator (Adm‐Br) was prepared by the treatment of 1‐[[N‐[2‐Hydroxy‐l,l‐bis(hydroxymethyl)ethyl]amino]carbonyl]adamantane with bromopropionyl bromide. The resulting initiator was subsequently used in the atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) to form (Adm‐p‐MMA), which was successfully used, as a macroinitiator, in further ATRP reactions with 3‐O‐methacryloyl‐1,2 5,6‐di‐O‐isopropylidene‐α‐d ‐glucofuranose (gly), a glycomonomer, to afford the Adm‐p‐MMA‐b‐gly polymer. The new Adm‐p‐MMA‐b‐gly polymer subsequently was employed to form a nanocomposite with chitosan‐modified, Nanofil clay (NC). The resulting Adm‐p‐MMA‐b‐gly/NC composite material was progressively hydrolyzed to regenerate the OH groups of the glucose units within the Adm‐p‐MMA‐b‐gly copolymer. The polymer/NC nanocomposites were characterized by X‐ray diffraction, thermal gravimetric analysis, differential scanning calorimetry, and transmission electron microscopy. POLYM. ENG. SCI., 54:2669–2675, 2014. © 2013 Society of Plastics Engineers 相似文献
49.
María Silvina Juárez Tomás Elena Bru María Elena Nader‐Macías 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(1):91-99
BACKGROUND: The culture medium for optimal growth of vaginal Lactobacillus salivarius CRL 1328 is different from that for optimal bacteriocin production. To simultaneously obtain high amount of biomass and bacteriocin of this microorganism, the effects of different basal culture media and salts on both responses were evaluated. The study was performed by using a complete factorial experimental design 26, with central points. Sixty‐four different growth media, which resulted from the combinations of two basal culture media and two concentrations of five salts (ammonium citrate, sodium acetate, MgSO4, MnSO4, and K2HPO4) were assayed. RESULTS: Only the addition of MnSO4 to each culture medium significantly stimulated the growth of L. salivarius. The presence of sodium acetate or MgSO4 stimulated the bacteriocin production, while MnSO4 and K2HPO4 exerted an inhibitory effect. However, the simultaneous addition of MnSO4 and sodium acetate to both basal culture media allowed high bacteriocin levels to be reached, attenuating the inhibitory effect of Mn2+. CONCLUSIONS: The application of a complete experimental design contributed to simultaneous optimization of the biomass and bacteriocin production of L. salivarius CRL 1328. The results obtained are potentially applicable to the technological production of probiotic bacteria and antagonistic substance to be included in a probiotic pharmaceutical product. Copyright © 2009 Society of Chemical Industry 相似文献
50.
Enhancement of immune response in mice fed with Streptococcus thermophilus and Lactobacillus acidophilus 总被引:1,自引:0,他引:1
G Perdigon M E Nader de Macias S Alvarez G Oliver A A Pesce de Ruiz Holgado 《Journal of dairy science》1987,70(5):919-926
Swiss mice, fed for 8 consecutive d with 50 micrograms/d of viable cultures of Lactobacillus acidophilus and Streptococcus thermophilus, showed significant variation in their immune system. In order to study this phenomenon assays for macrophage and lymphocyte function were carried out. Both lactic acid bacteria enhanced significantly the enzymatic and phagocytic activity of peritoneal macrophages as checked against the controls and also accelerated the phagocytic function of the reticuloendothelial system as revealed by the carbon clearance test. On the 2nd d (100 micrograms), L. acidophilus reached a peak of K = .271, which remained high. Streptococcus thermophilus was effective only on the 2nd d and then decreased. The lymphocytic activity studied by immunoglobulin secreting cells was assayed by Jerne's method of plaque-forming cells (PFC). This activity also was increased by the two microorganisms. Streptococcus thermophilus proved more effective than L. acidophilus. Lactobacillus acidophilus and S. thermophilus activated macrophages and lymphocytes and produced the same increase in the immune response of mice whether administered orally or intraperitoneally. 相似文献