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81.
Mayer F. Stephan; Duval Shelley; Duval Virginia H. 《Canadian Metallurgical Quarterly》1980,39(6):1072
C. A. Kiesler (1971) suggested that commitment to an act can be equated with feelings of self-responsibility for that act. This analysis implies that factors affecting attribution of self-responsibility for an act should also affect commitment. Two studies with a total of 93 male undergraduates supported the notion that attribution of self-responsibility for an act increases commitment to that act. Increasing self-focus (Exp I) increased commitment, and increasing the number of plausible causes present (Exp II) decreased commitment to a chosen act. Furthermore, in an effort to determine the role that perceived choice plays in the attributional process leading to commitment, perceived choice was also manipulated. Results indicate that choice clearly affected attribution to self and thus commitment, but choice did not appear to be absolutely essential to that process. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Based on questionnaire data, personal characteristics, income level, and clientele of private clinicians in southeastern cities are described, with emphasis on sex differences. There were fewer females in private practice, and no female therapist reported adult males as the primary clientele. Females experienced less full-time work and economic growth than males. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
Virginia A. Lee Klaus Lorenz Andrew D. Singleton 《Critical reviews in food science and nutrition》1979,11(1):41-116
The nutritional value of milk as an important source of energy, high‐quality protein, calcium, and riboflavin has been recognized for many years. Currently, the widespread use and promotion of milk in the U.S. as well as developing countries has been questioned. This review examines the nutrient composition of dairy products, factors that account for variability in composition of milk, milk processing, preservation, quality control, and contaminants (such as minerals, radionuclides, antibiotics, microorganisms and their metabolites, herbicides, and insecticides) in milk. Consumption patterns for milk and evidence for its nutritional value, especially in children, are presented. Milk consumption has been related to disease or conditions such as atherosclerosis, milk allergy, lactose intolerance, anemia, dental problems, and others. Recent recommendations for dietary changes for individuals in the U.S. and other developed countries could affect the use of milk. In addition, the use of feeding programs in the U.S. and developing countries which are based primarily on milk has been criticized. The preparation of new types of milk designed to offset certain difficulties encountered with cow's milk are now being evaluated in humans. 相似文献
84.
Specimens with complicated, intricate three-dimensional structures, which are otherwise difficult to coat adequately by conventional means (sputter or evaporative coating) for scanning electron microscopy, can quickly and simply be rendered conductive by electroless plating. The technique can be recommended only when studying specimens at low magnification because fine detail may be lost. 相似文献
85.
Roberto Sastre Virginia Martín Leoncio Garrido José Luis Chiara Beatriz Trastoy Olga García Angel Costela Inmaculada García‐Moreno 《Advanced functional materials》2009,19(20):3307-3316
Here, the design, synthesis, and characterization of laser nanomaterials based on dye‐doped methyl methacrylate (MMA) crosslinked with octa(propyl‐methacrylate) polyhedral oligomeric silsesquioxane (8MMAPOSS) is reported in relation to their composition and structure. The influence of the silicon content on the laser action of the dye pyrromethene 567 (PM567) is analyzed in a systematic way by increasing the weight proportion of POSS from 1 to 50%. The influence of the inorganic network structure is studied by replacing the 8MMAPOSS comonomer by both the monofunctionalized heptaisobutyl‐methacryl‐POSS (1MMAPOSS), which defines the nanostructured linear network with the POSS cages appearing as pendant groups of the polymeric chains, and also by a new 8‐hydrogenated POSS incorporated as additive to the polymeric matrices. The new materials exhibit enhanced thermal, optical, and mechanical properties with respect to the pure organic polymers. The organization of the molecular units in these nanomaterials is studied through a structural analysis by solid‐state NMR. The domain size of the dispersed phase assures a homogeneous distribution of POSS into the polymer, thus, a continuous phase corresponding to the organic matrix incorporates these nanometer‐sized POSS crosslinkers at a molecular level, in agreement with the transparency of the samples. The silicon–oxygen core framework has to be covalently bonded into the polymer backbone instead of being a simple additive and both the silica content and crosslinked degree exhibit a critical influence on the laser action. 相似文献
86.
Rosa Baeza Adriana Pérez Virginia Sánchez María C. Zamora Jorge Chirife 《Food and Bioprocess Technology》2010,3(1):87-92
Norrish’s equation,
a\textw = X\textw exp( - KX2\texts )a_{{\text{w}}} = X_{{\text{w}}} \exp {\left( { - KX^{2}_{{\text{s}}} } \right)}, where a
w is water activity, X
w and X
s are molar fractions of water and solute, respectively, and K is the correlating constant, has been widely used to predict a
w of aqueous nonelectrolyte solutions in connection with development of intermediate moisture foods, i.e., food having a
w ≥ 0.85. Present work evaluated the ability of Norrish’s equation to model the water activity of solutions of sugars, polyols,
and some polyethylene glycols, in a wide range of concentration, i.e., from low to highly concentrated solutions. For sugar
and polyols, a relatively small modification of the “most accepted” literature parameters K allowed the fitting of the data for the wide range of solute concentrations corresponding to a range of a
w from 0.99 to about 0.3 for same solutes. However, a modified Norrish’s model needs to be used to model the behavior of polyethylene
glycols 400 and 600 up to water activities as low as 0.5. 相似文献
87.
Raúl Avila-Sosa María Guadalupe Gastélum-Franco Alejandro Camacho-Dávila José Vinicio Torres-Muñoz Guadalupe Virginia Nevárez-Moorillón 《Food and Bioprocess Technology》2010,3(3):434-440
Antimicrobial activity of fractions obtained from Mexican oregano (Lippia berlandieri Schauer) chloroform extract was tested by growth inhibition against Escherichia coli, Staphylococcus aureus and Bacillus cereus, and antioxidant capacity was tested by inhibition of linoleic acid oxidation. Fractions were obtained by differences in
polarity or structure (phenolic and non-phenolic fraction). Gram-positive organisms were more susceptible to Mexican oregano
extracts. Fraction 3 (by polarity) and phenolic fractions I, II, III, IV and V were the extracts with higher antimicrobial
activity. The non-phenolic fraction had effect against B. cereus. Polarity fraction 5 and phenolic Fraction II had a high antioxidant capacity; a 0.08% concentration of fraction 5 had a
similar effect as butylated hydroxytoluene at 0.01% concentration. Fractions of Mexican oregano with different polarity and
functional groups had antioxidant and antimicrobial activity and can be used in a variety of applications. 相似文献
88.
Mortality due to lung, laryngeal and bladder cancer in towns lying in the vicinity of combustion installations 总被引:1,自引:0,他引:1
Javier García-Pérez Marina Pollán Elena Boldo Beatriz Pérez-Gómez Nuria Aragonés Virginia Lope Rebeca Ramis Enrique Vidal Gonzalo López-Abente 《The Science of the total environment》2009,407(8):2593-2602
Background
Installations that burn fossil fuels to generate power may represent a health problem due to the toxic substances which they release into the environment.Objectives
To investigate whether there might be excess mortality due to tumors of lung, larynx and bladder in the population residing near Spanish combustion installations included in the European Pollutant Emission Register.Methods
Ecologic study designed to model sex-specific standardized mortality ratios for the above three tumors in Spanish towns, over the period 1994-2003. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. Using mixed Poisson regression models, we analyzed: risk of dying from cancer in a 5-kilometer zone around installations that commenced operations before 1990; effect of type of fuel used; and risk gradient within a 50-kilometer radius of such installations.Results
Excess mortality (relative risk, 95% confidence interval) was detected in the vicinity of pre-1990 installations for lung cancer (1.066, 1.041-1.091 in the overall population; 1.084, 1.057-1.111 in men), and laryngeal cancer among men (1.067, 0.992-1.148). Lung cancer displayed excess mortality for all types of fuel used, whereas in laryngeal and bladder cancer, the excess was associated with coal-fired industries. There was a risk gradient effect in the proximity of a number of installations.Conclusions
Our results could support the hypothesis of an association between risk of lung, laryngeal and bladder cancer mortality and proximity to Spanish combustion installations. 相似文献89.
Deteriorating effects of lichen and microbial colonization of carbonate building rocks in the Romanesque churches of Segovia, Spain 总被引:1,自引:0,他引:1
de Los Ríos A Cámara B García Del Cura MA Rico VJ Galván V Ascaso C 《The Science of the total environment》2009,407(3):1123-1134
In this study, the deterioration effects of lichens and other lithobionts in a temperate mesothermal climate were explored. We examined samples of dolostone and limestone rocks with visible signs of biodeterioration taken from the exterior wall surfaces of four Romanesque churches in Segovia (Spain): San Lorenzo, San Martín, San Millán and La Vera Cruz. Biofilms developing on the lithic substrate were analyzed by scanning electron microscopy. The most common lichen species found in the samples were recorded. Fungal cultures were then obtained from these carbonate rocks and characterized by sequencing Internal Transcribed Spacers (ITS). Through scanning electron microscopy in back-scattered electron mode, fungi (lichenized and non-lichenized) were observed as the most frequent microorganisms occurring at sites showing signs of biodeterioration. The colonization process was especially conditioned by the porosity characteristics of the stone used in these buildings. While in dolostones, microorganisms mainly occupied spaces comprising the rock's intercrystalline porosity, in bioclastic dolomitized limestones, fungal colonization seemed to be more associated with moldic porosity. Microbial biofilms make close contact with the substrate, and thus probably cause significant deterioration of the underlying materials. We describe the different processes of stone alteration induced by fungal colonization and discuss the implications of these processes for the design of treatments to prevent biodeterioration. 相似文献
90.
Sabrine Bilel Micaela Tirri Raffaella Arf Chiara Sturaro Anna Fantinati Virginia Cristofori Tatiana Bernardi Federica Boccuto Marco Cavallo Alessandro Cavalli Fabio De-Giorgio Girolamo Cal Matteo Marti 《International journal of molecular sciences》2021,22(14)
1-cyclohexyl-x-methoxybenzene is a novel psychoactive substance (NPS), first discovered in Europe in 2012 as unknown racemic mixture of its three stereoisomers: ortho, meta and para. Each of these has structural similarities with the analgesic tramadol and the dissociative anesthetic phencyclidine. In light of these structural analogies, and based on the fact that both tramadol and phencyclidine are substances that cause toxic effects in humans, the aim of this study was to investigate the in vitro and in vivo pharmacodynamic profile of these molecules, and to compare them with those caused by tramadol and phencyclidine. In vitro studies demonstrated that tramadol, ortho, meta and para were inactive at mu, kappa and delta opioid receptors. Systemic administration of the three stereoisomers impairs sensorimotor responses, modulates spontaneous motor activity, induces modest analgesia, and alters thermoregulation and cardiorespiratory responses in the mouse in some cases, with a similar profile to that of tramadol and phencyclidine. Naloxone partially prevents only the visual sensorimotor impairments caused by three stereoisomers, without preventing other effects. The present data show that 1-cyclohexyl-x-methoxybenzene derivatives cause pharmaco-toxicological effects by activating both opioid and non-opioid mechanisms and suggest that their use could potentially lead to abuse and bodily harm. 相似文献