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1.
The colour stability of juice and purées made from a mixture of two strawberry varieties, stored at + 20°C or at –20°C under aerobic and anaerobic conditions, was studied. High-performance liquid chromatography and spectrophotometric analysis were used to monitor the changes in colour during storage. Pelargonidin 3-glucoside comprised 80% of the total anthocyanin content. Four other pelargonidin-based peaks were found, being 10.4%, 3.5%, 0.7% and 0.3% of the total and two cyanidin peaks were present, being 3.3% and 0.4% of the total. Clarification before storage caused considerable losses in the initial anthocyanin concentrations. Storage conditions (air versus nitrogen) did not influence the rate of loss of anthocyanins during storage or the formation of polymeric pigments. There were no losses in anthocyanins and no increase in the amount of colour measured at 510 nm due to polymers in samples stored at–20°C. Polymerisation occurred in the samples stored at + 20°C, especially in the clarified samples.  相似文献   
2.
OBJECTIVE: To investigate the effect of diphtheria toxin interleukin 2 recombinant fusion protein (DAB 486IL-2) on in vitro synthesis of immunoglobulin and rheumatoid factor (RF) in patients with severe refractory rheumatoid arthritis (RA) enrolled in a phase II, double blind, placebo controlled study. METHODS: Anticoagulated venous blood samples were obtained before (Day 1) and after (Day 28) intravenous infusion of either DAB 486IL-2 at 0.075 mg/kg/day (12 patients) or saline placebo (10 patients) on Days 1-5. Peripheral blood leukocytes (PBL) were prepared by density gradient centrifugation, cultured in the presence and absence of pokeweed mitogen (PWM) for one week, and culture supernatants assayed for immunoglobulins and IgM RF by ELISA. RESULTS: Compared to placebo treated patients, PWM induced IgM RF synthesis by PBL decreased after treatment with DAB 486IL-2 (p = 0.043). However, there was no apparent correlation with clinical improvement. PWM induced IgM, IgA, and IgG synthesis also tended to decrease, although the changes did not attain statistical significance. In contrast, PWM induced IgM RF, IgM, IgA, and IgG synthesis by PBL from patients treated with placebo tended to increase during the observation period. Spontaneous immunoglobulin and IgM RF production by PBL from either the DAB 486IL-2 or placebo patients remained stable. CONCLUSION: These observations raise the possibility that DAB 486IL-2 may diminish B cell function either directly or indirectly through effects on T cell function, but the change may not correspond to clinical response.  相似文献   
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Fast Filtering and Smoothing for Multivariate State Space Models   总被引:1,自引:0,他引:1  
This paper investigates a new approach to diffuse filtering and smoothing for multivariate state space models. The standard approach treats the observations as vectors, while our approach treats each element of the observational vector individually. This strategy leads to computationally efficient methods for multivariate filtering and smoothing. Also, the treatment of the diffuse initial state vector in multivariate models is much simpler than in existing methods. The paper presents details of relevant algorithms for filtering, prediction and smoothing. Proofs are provided. Three examples of multivariate models in statistics and economics are presented for which the new approach is particularly relevant.  相似文献   
5.
The aim of this study was to determine whether psychological adjustment to advanced breast cancer was positively associated with expressing emotion and adopting a fighting spirit and negatively associated with denial and fatalism. Total mood disturbance on the Profile of Mood States was used as the measure of psychological adjustment. The Courtauld Emotional Control Scale measured emotional expression, and the Mental Adjustment to Cancer measured fighting spirit, denial, and fatalism. The sample included 101 women with a diagnosis of metastatic or recurrent breast cancer. Fighting spirit and emotional expressiveness were found to be associated with better adjustment. No association was found between mood disturbance and denial or fatalism. Because this was a cross-sectional study, no conclusions regarding a causal relationship between adjustment and emotional expressiveness or adjustment and fighting spirit were possible. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
The desipramine-sensitive uptake (neuronal uptake) of 14C-bretylium and 14C-bethanidine into the rabbit aortic adventitial layer from 3 X 10(-6) M solutions increased with time during a 20 min incubation. For both compounds a neuronal uptake of 50 pmol/50 mg wet weight adventitia was associated with 10% block of the contractile response to field stimulation at 16 Hz and 150 pmol/50 mg with 60% block. The concentration of blocking agents inside the neuron at 50% blockade was calculated to be 260 X 10(-6) M, an 87-fold increase over the medium. The bretylium in the neuron decreased by 50% during 20 min washout, and bethanidine by 29%. Desipramine when added to the bath 20 min following the addition of the blocking agents led to a loss of bretylium but not of bethanidine from the adventitia. Desipramine had little or no effect on the uptake, washout or disposition of either blocking agent in the media-intimal layers. The data indicate that bretylium has a greater propensity than bethanidine to be lost from the neurons; however, it appears to be recycled back through the membrane via the amine pump more readily than bethanidine. The fact that conservative calculations indicate that the neuronal membrane slowly established a concentration of the blocking agents within the neuron that is known to produce rapid local anesthesia when topically applied to adrenergic nerve trunks and which approaches a concentration needed to inhibit sensory endings suggests that local anesthesia may play a role in the mechanism of neuron blockade.  相似文献   
7.
Embedded control networks commonly use checksums to detect data transmission errors. However, design decisions about which checksum to use are difficult because of a lack of information about the relative effectiveness of available options. We study the error detection effectiveness of the following commonly used checksum computations: exclusive or (XOR), two's complement addition, one's complement addition, Fletcher checksum, Adler checksum, and cyclic redundancy codes (CRC). A study of error detection capabilities for random independent bit errors and burst errors reveals that XOR, two's complement addition, and Adler checksums are suboptimal for typical network use. Instead, one's complement addition should be used for networks willing to sacrifice error detection effectiveness to reduce compute cost, Fletcher checksum for networks looking for a balance of error detection and compute cost, and CRCs for networks willing to pay a higher compute cost for significantly improved error detection.  相似文献   
8.
Proposed modifications of the standard sludge volume index (SVI) to eliminate its unpredictable variation with suspended solids (SS) concentration include stirring, conduct of the test at constant SS concentration, and dilution. We have tested these modifications by making correlations between the respective indices and the content of filamentous organisms in activated sludge expressed in terms of total extended filament length. The results indicate that diluted SVI is the best index of sludge settleability among those tested. Correlation of diluted SVI with specific functional relationships between settling velocity and SS concentration would enable the application of this parameter to prediction of thickening capacity in secondary clarifiers.  相似文献   
9.
This study examined relationships between dissociative symptoms experienced in the immediate aftermath of the Oakland/Berkeley firestorm and contact with the fire, life events, demographic variables, and actions taken after learning about the fire. One hundred eighty-seven participants completed self-report measures about their experiences during and immediately following the fire. Dissociative symptoms were significantly related to contact with the fire, sex, and stressful life events. Also, dissociative symptoms were significantly related to engaging in certain activities, such as trying to get closer to the fire and going into blocked-off areas and crossing police barricades. These results suggest that dissociative symptoms may merit special attention in intervention focusing on the immediate aftermath of disaster.  相似文献   
10.
Large scale spills of volatile cryogenic or pressurized ambient temperature liquids often produce denser-than-air clouds which disperse in the atmosphere in a manner that is different than trace gases. These differences are due to density or gravity-induced effects such as turbulence damping from the stable density stratification, alteration of the ambient velocity field due to gravity flow, and the source momentum flux. Also important are thermodynamic effects such as aerosol formation and flash vaporization upon release, evaporative cooling, or heat transfer from the ground modifying cloud buoyancy and turbulence. In addition, chemical reaction effects such as hydrolysis with atmospheric water vapor, polymerization, or decomposition which also affects cloud density and thermodynamics can be important. These effects are very important close to the release point but also can have dramatic effects on the cloud as it disperses downwind.

Large scale tests involving releases of heavy gases have been conducted since the early 1970's. These tests have resulted in the discovery of previously unknown and important effects, the accumulation of data for model validation, as well as accident simulation and evaluation of accident mitigation equipment and techniques. A review of recent tests and some of the important results will be presented and examples from recent test series will be used in a review of our current understanding of dense gas dispersion.

The status of computer modeling in this field will also be reviewed with an emphasis on the problems associated with Gaussian models and recent progress in intermediate and 3D conservation equation models. Two of these models, FEM3 and SLAB will be compared to data so that the observed phenomena can be understood and so that predictions can be made regarding the consequences of accidental spills of sizes of concern to industry. FEM3 simulates the dispersion of the released gas by solving the time-dependent, three-dimensional conversion equations of mass, momentum, energy, and species. This model is used as a research tool and is designed to simulate as closely as possible the physics and thermodynamics governing the dispersion process. Steady-State SLAB is based on the crosswind-averaged form of the conservation equations, using similarity profiles to determine the crosswind dependence. It also conserves mass, momentum, energy and species, but is inherently one-dimensional, and is computationally simple and fast to use.  相似文献   
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