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91.
Marisa Ziino Concetta Condurso Vincenza Romeo Gianluca Tripodi Antonella Verzera 《Journal of the science of food and agriculture》2009,89(5):774-780
BACKGROUND: Because of the great variability in size, shape, colour, pungency and aroma of Calabrian Capsicum annuum(hot pepper), this study was carried out to furnish producers with information on volatile compounds and capsaicinoid content useful for the genetic improvement of this species. Fully ripened fresh peppers of the most widely cultivated varieties were studied. Capsaicinoid content was determined by reverse phase high‐performance liquid chromatography/diode array detection (RP‐HPLC/DAD). Volatile compounds were determined by headspace solid phase microextraction/gas chromatography/mass spectrometry (HS‐SPME/GC/MS). RESULTS: Sixty‐four volatile compounds were identified, the main classes being alcohols, aldehydes, terpenes and aliphatic branched‐chain hydrocarbons. The ‘Naso di cane’ (C. annuumvar. abbreviatum) variety contained the lowest amount of volatiles, especially alcohols and aldehydes, while the highest levels of capsaicin and dihydrocapsaicin were found in ‘Vulcan’ and ‘Corno di capra’ varieties. CONCLUSION: From statistical evaluation of the data obtained, each variety showed a typical composition of capsaicinoids and volatiles determining the taste and odour of the hot peppers. These results should be useful in the context of research aimed at selecting varieties with the best sensory characteristics. Copyright © 2009 Society of Chemical Industry 相似文献
92.
Luiz C. A. Bastos Waldinei R. Monteiro Marisa A. Zacharias Gilberto M. da Cruz José Augusto J. Rodrigues 《Catalysis Letters》2008,120(1-2):48-55
Molybdenum and tungsten bimetallic oxides were synthetized according to the following methods: Pechini, coprecipitation and
solid state reaction (SSR). After the characterization, those solids were carbureted at programmed temperature. The carburation
process was monitored by checking the consumption of carburant hydrocarbon and CO produced. The monitoring process permits
to avoid or to diminish the formation of pirolytic carbon. 相似文献
93.
A large body of work has revealed that people remember emotionally arousing information better than neutral information. However, previous research has revealed contradictory effects of emotional events on memory for neutral events that precede or follow them: In some studies, emotionally arousing items have impaired memory for immediately preceding or following items, and in others arousing items enhanced memory for preceding items. By demonstrating both emotion-induced enhancement and impairment, Experiments 1 and 2 clarified the conditions under which these effects are likely to occur. The results suggest that emotion-induced enhancement is most likely to occur for neutral items that (a) precede (and so are poised to predict the onset of) emotionally arousing items, (b) have high attentional weights at encoding, and (c) are tested after a delay period of a week rather than within the same experimental session. In contrast, emotion-induced impairment is most likely to occur for neutral items near the onset of emotional arousal that are overshadowed by highly activated competing items during encoding. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Gillham Jane E.; Reivich Karen J.; Freres Derek R.; Chaplin Tara M.; Shatté Andrew J.; Samuels Barbra; Elkon Andrea G. L.; Litzinger Samantha; Lascher Marisa; Gallop Robert; Seligman Martin E. P. 《Canadian Metallurgical Quarterly》2007,75(1):9
The authors investigated the effectiveness and specificity of the Penn Resiliency Program (PRP; J. E. Gillham, L. H. Jaycox, K. J. Reivich, M. E. P. Seligman, & T. Silver, 1990), a cognitive-behavioral depression prevention program. Children (N = 697) from 3 middle schools were randomly assigned to PRP, Control (CON), or the Penn Enhancement Program (PEP; K. J. Reivich, 1996; A. J. Shatté, 1997), an alternate intervention that controls for nonspecific intervention ingredients. Children's depressive symptoms were assessed through 3 years of follow-up. There was no intervention effect on average levels of depressive symptoms in the full sample. Findings varied by school. In 2 schools, PRP significantly reduced depressive symptoms across the follow-up relative to both CON and PEP. In the 3rd school, PRP did not prevent depressive symptoms. The authors discuss the findings in relation to previous research on PRP and the dissemination of prevention programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
96.
Ana Lúcia N. Da Silva Marisa C. G. Rocha Fernanda M. B. Coutinho Rosrio Bretas Carlos Scuracchio 《应用聚合物科学杂志》2000,75(5):692-704
Rheological and morphological studies were performed on polymer blends of ethylene‐octene copolymer [polyethylene elastomer (PEE)] and polypropylene (PP). The viscosities of PEE, PP, and PEE/PP blends were analyzed using an Instron capillary rheometer and a Rheometrics Dynamic Stress Rheometer, SR 200. A non‐Newtonian flow behavior was observed in all samples in the shear rate range from 27 to 2700 s−1, whereas at shear rates in the range from 0.01 to 0.04 s−1, a Newtonian flow behavior was verified. The scanning electron micrographs showed that dual‐phase continuity may occur between 50 and 60 (wt %) of PEE. This result is consistent with the Sperling's model. The mechanical analysis showed that PEE/PP, with 5 wt % of PEE, presented an increase on the mechanical properties and as the PEE content increased, a negative deviation in relation to an empirical equation was observed. Thermal analysis showed that there were no change in the crystallization behavior of the matrix when different elastomer contents were added. Dynamic mechanical thermal analysis showed that samples with low PEE contents presented only one peak, indicating a certain degree of miscibility between the components of these blends. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 692–704, 2000 相似文献
97.
Solomon Paul R.; Brett Marisa; Groccia-Ellison Mary Ellen; Oyler Catherine; Tomasi Marie; Pendlebury William W. 《Canadian Metallurgical Quarterly》1995,10(2):248
Previous studies demonstrated that patients with Alzheimer's disease (AD) do not acquire the classically conditioned eyeblink response. These studies, however, were only tested over a single conditioning session and, hence, raise the question of whether AD patients are capable of acquiring the response if sufficient training is given. This question may be of some importance because whether AD patients can ultimately acquire the response has implications for the underlying neurobiological deficit in disrupted conditioning in AD. This study tested AD patients and age-matched controls over 4 days. As in previous studies, AD patients performed significantly worse than controls on Day 1, but by Day 4, they were not significantly different from controls. Subsequent testing indicated that these effects were not due to nonassociative variables such as changes in sensitivity to stimuli or disruption of the motor response. Also, it was reported that neither AD patients nor controls showed any evidence of acquisition in an explicitly unpaired paradigm, suggesting that neither pseudoconditioning nor sensitization is contributory. Data are discussed in terms of the possible role of the hippocampus in mediating conditioning deficits in AD patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
99.
Marisa Manzano Cristina Giusto Ingrid Bartolomeoli Stefano Buiatti Giuseppe Comi 《Journal of the Institute of Brewing》2005,111(2):203-208
Classical microbiological methods in association with molecular methods (DNA amplification, Temperature Gradient Gel Electrophoresis (TGGE) and Denaturing Gradient Gel Electrophoresis (DGGE) were used. These methods, developed to rapidly analyze microbial communities on the basis of sequence‐specific separation of DNA amplicons, allowed the detection of DNA differences in the amplicons tested and the identification of the strains analyzed by the comparison of unknown sequences with sequences of known species. TGGE allowed the comparison of the different Saccharomyces cerevisiae strains used in brewing while DGGE allowed the identification of lactic acid bacteria (LAB) in beer. These methods are a reliable tool for fast comparison of strains of Saccharomyces cerevisiae collected from different craft breweries where they were used as starters to check the presence of possible yeast contaminants in the brewing process and for rapid LAB identification. 相似文献
100.