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91.
92.
Pier Luigi Beltrame Ernestina Dubini-Paglia Bruno Marcandalli Patrizia Sadocco Alberto Seves 《应用聚合物科学杂志》1987,33(8):2965-2974
Three poly(ethylene terephthalate) films were prepared having the same crystallinity but different morphology. They were colored with azo dyes XC6H4N = NC6H4N(C2H5)2 (where X is H, OCH3, CN, and COOC2H5). The kinetics of the thermal cis-trans isomerization of these dyes has been studied below the glass transition temperature in the range 25–56°C. The isomerization process was found to be the result of a multiplicity of first-order reactions. The kinetic parameters have been correlated with the order degree at molecular level of the polymer. Lightfastness of the dyes in the polymer matrices has been also investigated: it appeared to be in relation with the supermolecular structure of the film. 相似文献
93.
Oliverio Alberto; Castellano Claudio; Messeri Patrizia 《Canadian Metallurgical Quarterly》1972,79(3):459
Conducted a genetic analysis of avoidance, maze learning, and wheel-running activity in 1,573 SEC/1ReJ, DBA/2J, and C57BL/6J strain mice and their F1, F2, and F3 progenies. Results show that the mode of inheritance in a given behavioral measure depends on the crosses considered. Thus, a given allele may be dominant in a given hybrid combination and recessive in another combination. The significant genetic correlations between these 3 behavioral measures suggest that these traits could be influenced by some of the same genes. The estimates of heritability are larger for avoidance than for activity, suggesting that the latter trait is more related to fitness. (36 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Zucca C Tavella P 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2005,52(2):289-296
The clock errors are modeled by stochastic differential equations (SDE) and the relationships between the diffusion coefficients used in SDE and the Allan variance, a typical tool used to estimate clock noise, are derived. This relationship is fundamental when a mathematical clock model is used, for example in Kalman filter, noise estimation, and clock prediction activities. 相似文献
95.
Patrizia Casero Marcello Duranti Paolo Cerletti 《Journal of the science of food and agriculture》1983,34(10):1113-1116
The subunit compositions of a legumin-like (globulin 8) and a vicilin-like protein (globulin 4) extracted from a plurality of seeds and from a single seed both in commercial and in a selected cultivar of Lupinus albus were studied. In the case of globulin 4, a very similar number of bands were observed in SDS-PAGE, in the protein extracted from a batch of seed and in the same globulin isolated from a single seed. For globulin 8 the SDS-PAGE pattern showed fewer subunits in the protein from the batch of seeds than in that from a single seed. This is more pronounced in the single seed and in the plurality of seeds of a selected cultivar. Reasons for this behaviour are discussed. 相似文献
96.
97.
G Bertolini R D'Amico G Apolone A Cattaneo A Ravizza G Iapichino L Brazzi RM Melotti 《Canadian Metallurgical Quarterly》1998,36(9):1371-1382
OBJECTIVES: This study sought to compare the performance of the old and new versions of the Simplified Acute Physiology Score, SAPS and SAPS II, in classifying patients according to the risk of hospital mortality. METHODS: To compare the performance of the two systems, measures of association between the scores and observed mortality were adopted, together with discrimination (area under the Receiver Operating Characteristics curve) and calibration (goodness-of-fit statistics) estimates. Subjects were 1,393 eligible patients recruited during 1 month in 1994. The outcome measure was vital status at hospital discharge. RESULTS: SAPS II was associated more strongly with hospital mortality than the earlier version. SAPS II also had better discrimination ability than SAPS (area under Receiver Operating Characteristics curve 0.80 versus 0.74) and predicted an overall number of deaths (416.5) closer to the observed figure (475) than SAPS (267.7). Conversely, neither SAPS nor SAPS II fitted our data. Both P values derived from goodness-of-fit statistics were lower than 0.05. CONCLUSIONS: SAPS II offers a real improvement compared with SAPS in its ability to explain hospital mortality, but its standard parameters do not fit our data from Italy. The role and impact of potential determinants of this lack of fit, such as random errors and confounders related to casemix and/or quality of care should be clarified before this scoring system be used outside formal research projects. Special caution is suggested when SAPS II is adopted to predict mortality to compare intensive care unit performance across different countries and systems of care. 相似文献
98.
Carpinella I Cattaneo D Bertoni R Ferrarin M 《IEEE transactions on neural systems and rehabilitation engineering》2012,20(3):351-360
In this pilot study, we compared two protocols for robot-based rehabilitation of upper limb in multiple sclerosis (MS): a protocol involving reaching tasks (RT) requiring arm transport only and a protocol requiring both objects' reaching and manipulation (RMT). Twenty-two MS subjects were assigned to RT or RMT group. Both protocols consisted of eight sessions. During RT training, subjects moved the handle of a planar robotic manipulandum toward circular targets displayed on a screen. RMT protocol required patients to reach and manipulate real objects, by moving the robotic arm equipped with a handle which left the hand free for distal tasks. In both trainings, the robot generated resistive and perturbing forces. Subjects were evaluated with clinical and instrumental tests. The results confirmed that MS patients maintained the ability to adapt to the robot-generated forces and that the rate of motor learning increased across sessions. Robot-therapy significantly reduced arm tremor and improved arm kinematics and functional ability. Compared to RT, RMT protocol induced a significantly larger improvement in movements involving grasp (improvement in Grasp ARAT sub-score: RMT 77.4%, RT 29.5%, p=0.035) but not precision grip. Future studies are needed to evaluate if longer trainings and the use of robotic handles would significantly improve also fine manipulation. 相似文献
99.
Maria Laura De Marchis Fiorella Guadagni Erica Silvestris Domenica Lovero David Della-Morte Patrizia Ferroni 《Critical reviews in food science and nutrition》2019,59(14):2308-2320
ABSTRACTMigraine is a common multifactorial and polygenic neurological disabling disorder characterized by a genetic background and associated to environmental, hormonal and food stimulations. A large series of evidence suggest a strong correlation between nutrition and migraine and indicates several commonly foods, food additives and beverages that may be involved in the mechanisms triggering the headache attack in migraine-susceptible persons. There are foods and drinks, or ingredients of the same, that can trigger the migraine crisis as well as some foods play a protective function depending on the specific genetic sensitivity of the subject. The recent biotechnological advances have enhanced the identification of some genetic factors involved in onset diseases and the identification of sequence variants of genes responsible for the individual sensitivity to migraine trigger-foods. Therefore many studies are aimed at the analysis of polymorphisms of genes coding for the enzymes involved in the metabolism of food factors in order to clarify the different ways in which people respond to foods based on their genetic constitution.This review discusses the latest knowledge and scientific evidence of the role of gene variants and nutrients, food additives and nutraceuticals interactions in migraine. 相似文献