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991.
Cell wall metabolism of peaches and nectarines treated with UV‐B radiation: a biochemical and molecular approach 下载免费PDF全文
992.
An aerobic enrichment culture was grown on vinyl chloride (VC) as the sole source of carbon and energy. In the absence of VC, the enrichment culture cometabolized cis-1,2-dichloroethene (cDCE) and, to a lesser extent, trans1,2-dichloroethene (tDCE), beginning with oxidation to the corresponding DCE-epoxides. When provided with VC (1.3 mM) and cDCE (0.2-0.3 mM), the enrichment culture cometabolized repeated additions of cDCE for over 85 days. Cometabolism of repeated additions of tDCE was also demonstrated but at a lower ratio of nongrowth substrate to VC. VC-grown Pseudomonas aeruginosa MF1 (previously isolated from the enrichment culture) also readily cometabolizes cDCE, with an observed transformation capacity (Tc,obs) of 0.82 micromol of cDCE/mg of total suspended solids (TSS). When provided with VC and cDCE, MF1 did not begin cometabolizing cDCE until nearly all of the VC was consumed. The presence of cDCE reduces the maximum specific rate of VC utilization. A kinetic model was developed that describes these phenomena via Monod parameters for substrate and nongrowth substrate, plus inactivation and inhibition coefficients. MF1 did not show any cometabolic activity on tDCE or trichloroethene and very limited activity on 1,1-DCE (Tc,obs = 2 x 10(-5) micromol/mg TSS). Above 40 microM, tDCE and TCE noticeably increased the maximum specific rate of VC utilization, even though neither compound was consumed during or after VC consumption. High concentrations of 1,1-DCE (950 microM) completely inhibited VC biodegradation. As there is currently no evidence for aerobic biodegradation of cDCE as a sole source of carbon and energy, the results of this study provide a potential explanation for in situ disappearance of cDCE when the only other significant substrate available is VC. It is fortuitous that the VC-grown cultures tested exhibit their highest cometabolic activity toward cDCE, because it is the predominant DCE isomer formed during anaerobic reductive dechlorination of trichloroethene and tetrachloroethene. 相似文献
993.
Claudia V. Goldman Dan Gang Jeffrey S. Rosenschein Daniel Lehmann 《Annals of Mathematics and Artificial Intelligence》1999,25(1-2):69-90
The system presented here shows the feasibility of modeling the knowledge involved in a complex musical activity by integrating
sub-symbolic and symbolic processes. This research focuses on the question of whether there is any advantage in integrating
a neural network together with a distributed artificial intelligence approach within the music domain. The primary purpose
of our work is to design a model that describes the different aspects a user might be interested in considering when involved
in a musical activity. The approach we suggest in this work enables the musician to encode his knowledge, intuitions, and
aesthetic taste into different modules. The system captures these aspects by computing and applying three distinct functions:
rules, fuzzy concepts, and learning. As a case study, we began experimenting with first species two-part counterpoint melodies.
We have developed a hybrid system composed of a connectionist module and an agent-based module to combine the sub-symbolic
and symbolic levels to achieve this task. The technique presented here to represent musical knowledge constitutes a new approach
for composing polyphonic music.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
994.
Investigated whether stereotypic knowledge would influence social perception in a more realistic setting. In Exp I, 96 undergraduates watched a videotape of a target woman identified either as a waitress or a librarian; Ss more accurately remembered features of the woman that were consistent with their prototype of a waitress (librarian) than features that were inconsistent. The prototype-consistency effect did not interact with the delay time before recognition memory was assessed. In Exp III, 56 Ss learned the occupational information either before or after watching the tape. The prototype-consistency effect from Exp I was replicated. In addition, knowing the target's occupation while watching her led to increased accuracy for both consistent and inconsistent information. The probable role of both encoding and retrieval processes in contributing to this effect is noted. Perceivers' stereotypic prior knowledge influenced their memory of a target person's behavior even in a realistic person-perception situation. Conditions that favor the memorability of consistent vs inconsistent information are discussed. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
996.
Estimated verbally and numerically the chances that specific events will occur using 6 analysts. 60 decision makers used each type of estimate to make binary-choice decisions and to bid for lotteries based on the events. The usual reversal of preference between choice and bidding procedures was found in the numerical condition, but the frequency of preference reversals was significantly reduced in the verbal condition. This reduction occurred because risk aversion was reduced in choice when verbal estimates were given, whereas bidding was unaffected by presentation mode. The pattern of results was predicted by and supports the hypothesis that the relative importance given to the dimensions of a prospect depends on the form in which the information is displayed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Cohen Patricia; Kasen Stephanie; Brook Judith S.; Hartmark Claudia 《Canadian Metallurgical Quarterly》1998,34(6):1202
Data from a random cohort of residents in a 2-county area were used to determine the stability in 2 major dimensions of childhood behavior between 2 generations. The 1st generation was assessed at mean age 7, and their offspring were assessed at age 2 years. Measures were used in latent-variable structural equation models to test the hypotheses. Strong stability in these behavior patterns in the 1st generation was shown between early childhood and a reassessment 8 years later. There was a significant stability between generations in the inhibited behavior pattern but not in the difficult pattern. This relationship was stronger when parents had been assessed at an age closer to that of their toddler offspring. Findings are consistent for mother–offspring, father–offspring, and daughter and son subsamples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Abstract. This note describes an improvement of Ishiguro's algorithm for the Bayesian decomposition of a time series based on the use of a specialized band Cholesky factorization. 相似文献
999.
Claudia C. Ruiz Mahendra Agraharkar 《Hemodialysis international. International Symposium on Home Hemodialysis》2003,7(4):356-359
Cellulitis in immunocompetent hosts is usually caused by skin organisms and responds to oral antibiotics. In immunocompromised hosts, such as end-stage renal disease (ESRD) patients, unusual organisms with unpredictable pathogenicity can cause infections. We present two cases with isolates that are usually encountered in coastal waters. The first case describes a 71-year-old African-American ESRD patient who presented with bacteremia secondary to a wound infection after exposure to flood waters in a tropical storm. The second case describes a 70-year-old Caucasian male ESRD patient who developed septic shock after a trivial wound inflicted while on a shrimp boat. Both patients were successfully treated with appropriate antibiotics and supportive measures.
The infective agents in both cases belong to the halophilic Vibrio species. The causative agent of cellulitis and bacteremia in the first hemodialysis patient was identified as Vibrio alginolyticus, a non-lactose-fermenting gram-negative bacillus that is rarely isolated from blood. The second patient presented with septic shock owing to Vibrio vulnificus, which is a lactose-fermenting bacillus known to produce severe localized or systemic illness. In both cases, the common features were ESRD-related immunocompromised state and exposure to marine environments. These two cases of life-threatening cellulitis and bacteremia are presented as examples of environmental pathogens common to a marine environment in coastal areas and the imperative need of rapid identification and prompt initiation of treatment in immunocompromised hosts. 相似文献
The infective agents in both cases belong to the halophilic Vibrio species. The causative agent of cellulitis and bacteremia in the first hemodialysis patient was identified as Vibrio alginolyticus, a non-lactose-fermenting gram-negative bacillus that is rarely isolated from blood. The second patient presented with septic shock owing to Vibrio vulnificus, which is a lactose-fermenting bacillus known to produce severe localized or systemic illness. In both cases, the common features were ESRD-related immunocompromised state and exposure to marine environments. These two cases of life-threatening cellulitis and bacteremia are presented as examples of environmental pathogens common to a marine environment in coastal areas and the imperative need of rapid identification and prompt initiation of treatment in immunocompromised hosts. 相似文献
1000.
Heinz Idstein Claudia Bauer und Peter Schreier 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1985,180(5):394-397
Zusammenfassung Die extraktiv (Pentan/Dichlormethan, 2 + 1) erfaßbaren flüchtigen Säuren in Fruchtpulpen von Tropenfrüchten sind mittels Capillargaschromatographie (HRGC) und Capillargaschromatographie-Massenspektrometrie (HRGC-EI/CIMS) identifiziert und bestimmt worden. In Cherimoya (A. cherimolia, Mill.)-Fruchtpulpe konnten 47 Säuren charakterisiert werden; Hauptkomponenten waren Hexan- (3 mg/kg) und Octansäure (1 mg/kg). In Guava (P. guajava, L.) sind 51, in Mango (M. indica, L., var. Alphonso) 54 und in Papaya (C. papaya, L.) 56 Säuren identifiziert worden. Als Hauptkomponenten wurden (E)-Zimtsäure (0,4 mg/kg) und (Z)-3-Hexensäure (0,2 mg/kg) in Guava, 5-Hydroxy-(Z)-7-decensäure (2 mg/kg) und 3-Hydroxyoctansäure (1,1 mg/kg) in Mango sowie Butansäure (1,2 mg/kg) in Papaya bestimmt.
Volatile acids from tropical fruits: cherimoya (Annona cherimolia, Mill.), guava (Psidium guajava, L.), mango (Mangifera indica, L., var. Alphonso), papaya (Carica papaya, L.)
Summary The volatile acids extracted by pentane/dichloromethane (2 + 1) from tropical fruit pulps were identified and determined by capillary gas chromatography (HRGC) and combined capillary gas chromatography-mass spectrometry using EI- and CI mode (HRGC-EI/CIMS). In cherimoya (A. cherimolia, Mill.) fruit pulp 47 acids were characterized; major compounds were hexanoic (3 mg/kg) and octanoic (1 mg/kg) acid. Fiftyone acids were identified in guava (P. guajava, L.), 54 in mango (M, indica, L., var. Alphonso) and 56 in papaya (C. papaya, L.). (E)-cinnamoic acid (0.4 mg/kg) and (Z)-3-hexanoic acid (0.2 mg/kg) were determined as major constituents in guava; in mango 5-hydroxy-(Z)-7-decenoic acid (2 mg/kg) and 3-hydroxyoctanoic acid (1.1 mg/kg) and in papaya pulp butanoic acid (1.2 mg/kg) were established as major constituents.相似文献