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1.
Preliminary results of an investigation focused on the influence of electrokinetic treatment on the mechanical and hydraulic behaviour of clayey soils are presented. The experimental programme aims at providing a contribution to the sustainability of contaminant extraction or containment via electroosmosis. Changes in the hydraulic and mechanical properties of two illitic clayey soils, subjected to a DC electric field, were investigated. Samples of the two soils were subjected to electrokinetic filtration, for different periods of time, and under different constant loads. Afterwards, they were tested under one-dimensional compression to detect changes in stiffness and hydraulic conductivity due to the electrical treatment. After the application of a DC field for a few hours, a small reversible increment in the average soil stiffness was observed, with respect to the untreated soil, while the hydraulic conductivity was not affected substantially. Dramatic changes of the mechanical and hydraulic soil properties, correlated to changes of the soil pH, were observed following non-conditioned electrokinetic treatment with duration of the order of days.  相似文献   
2.
Mussels (Mytilus galloprovincialis) were contaminated with known amounts of laboratory strains of hepatitis A virus and Poliovirus 1 and the effectiveness of a self-cleansing mechanism was studied using a pilot depuration system. Both viruses were rapidly bioaccumulated by mussels and the maximal concentration of about 10(4) TCID50/ml was reached within 1.5 hours. Depuration was carried out up to 24 h; infectivity titer decreased to 10(2) TCID50/ml and 10(3.2) TCID50/ml within 6 h in hepatitis A virus and Poliovirus 1 contaminated mussels, respectively, but only a very slight further decrease was obtained after 24 h. E. coli was used as a control; within 24 h the concentration decreased from 40 to 2 bacteria/ml of mussel (MPN). The elimination of bacteria is not a reliable parameter to control the effectiveness of viral depuration.  相似文献   
3.
The hepatitis A virus (HAV) and poliovirus 1 were added to estuarine water samples and their stability in maintenance medium was compared to that in water samples untreated and treated by heat and filtration. The inactivation curves show that the inactivating factor is biological in nature.  相似文献   
4.
Advances in our knowledge of the physiological functions of dietary polyunsaturated fatty acids (PUFAs) have led to an increased interest in food sources and the level of dietary intake of these nutrients. Up to now, no representative data was available for the Belgian adult population. This study aimed to describe data on the intake and food sources of total and individual omega-6 and omega-3 PUFA for the Belgian population over 15 years old. PUFA intakes were assessed for 3,043 Belgian adults, based on two non-consecutive 24 h recalls. Usual intakes were calculated using the multiple source method. The results showed that the intake of linoleic acid (LA) is in accordance with the recommendation for almost all Belgian adults. However, the intake of omega-3 PUFA is suboptimal for a large part of the studied population and also the intake of total PUFA should be increased for a part of the population. The main food source of LA and α-linolenic acid (ALA) was the group of fats and oils (60.6 % for LA and 53.1 % for ALA). Fish and fish products were the most important sources of long chain omega-3 PUFA. Age influenced fatty acids intake, with higher intake of omega-3 PUFA in the older age groups. To fill the gap between the intake and recommendation of total PUFA, and in particular omega-3 PUFA, sustainable strategies and efficient consumer communication strategies will be needed.  相似文献   
5.
6.
Application of mild inactivation treatments follows an increasing trend in the food industry and is often combined with sub-optimal intrinsic product conditions to ensure appropriate level of microbial safety. Listeria monocytogenes was subjected to mild heat treatment (20 min at 60 degrees C) and subsequently exposed to various mild preservation conditions based on increased NaCl concentration and decreased pH. Recovery and resuscitation of L. monocytogenes cells were studied using various methods. Using 12-fold Most Probable Number (MPN) method no difference in the amount of recovered cells under adverse conditions was noted between heat-treated and non-treated L. monocytogenes cells. Time-to-detection method using on-line OD measurements showed that heat-treated L. monocytogenes cells reached detection limit faster in acidified media and NaCl supplemented media in comparison with non-heated control cells. Flow cytometry (FCM) analysis using 5-6-carboxyfluorescein diacetate (cFDA) and propidium iodide (PI) staining showed presence of low numbers of viable cells. Overall, there was no indication of sub-lethal injury in L. monocytogenes cells after mild heat treatment.  相似文献   
7.
Burnout is generally defined as a state of severe exhaustion. So far, research has predominantly focused on relatively mild burnout in employees able to work despite their complaints. This study examines energy depletion in clinical burnout (e.g., the severest cases on extended sick leave) by comparing the diurnal patterns of fatigue and exhaustion with those of healthy individuals. Sixty clinically burned-out and 40 healthy participants kept an electronic diary for 14 days, 7 times a day, yielding a total of 8,116 diary entries. This study shows that burned-out individuals typically suffer continuously from a severe fatigue throughout the day. The resulting flattened diurnal cycles mark a stable exhaustion that is uncommon in healthy persons. The current results provide novel support for the existence of severe energy erosion in clinical burnout. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Statechart Diagrams provide a graphical notation for describing dynamic aspects of system behaviour within the Unified Modelling Language (UML). In this paper we present a translation from a subset of UML Statechart Diagrams - covering essential aspects of both concurrent behaviour, like sequentialisation, parallelism, non-determinism and priority, and state refinement - into PROMELA, the specification language of the SPIN model checker. SPIN is one of the most advanced analysis and verification tools available nowadays. Our translation allows for the automatic verification of UML Statechart Diagrams. The translation is simple, proven correct, and promising in terms of state space representation efficiency. Received September 1999 / Accepted in revised form February 2000  相似文献   
9.
The results of previous studies on visual perception suggest that conjunction errors partly derive from imperfect binding of correctly perceived features. However, the paradigms used in these studies do not generally allow one to discriminate between errors of feature binding and errors of target-nontarget confusion. In Experiments 1–4, an altered paradigm was used enabling discrimination between errors of feature binding and errors of target-nontarget confusion. The results showed that conjunction errors between color and identity do not derive from imperfect binding. In Experiments 5 and 6, a typical mainstream paradigm was used. The results indicated that, in such a paradigm, data patterns suggesting the existence of illusory conjunctions are likely to be due to errors of target-nontarget confusion instead of imperfect feature binding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Different forms of memory linked to specific brain regions were assessed in unmedicated adults with Gilles de la Tourette's syndrome (TS) and in normal controls of equivalent age and educational attainment. TS patients were impaired on measures of strategic, working, and procedural memory associated with fronto-striatal function. In contrast, their performance was intact on measures of immediate, semantic, and declarative memory associated with temporal-diencephalic functioning. These findings are consistent with radiological evidence of fronto-striatal abnormalities in TS and provide convergent evidence that a fronto-striatal memory system mediates working memory in humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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