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排序方式: 共有347条查询结果,搜索用时 15 毫秒
91.
92.
Krishna Vyncke Inge Huybrechts Myriam Van Winckel Magdalena Cuenca Garcia Idoia Labayen Frederic Gottrand Kurt Widhalm Catherine Leclercq Lars Libuda Yannis Manios Michael Sjostrom Denes Molnar Luis A. Moreno Marcela Gonzalez-Gross André Spinneker Fatima Perez de Heredia Maria Plada Stefaan De Henauw 《Lipids》2014,49(9):881-893
The present study aimed to assess the correlation between food and fatty acid (FA) intake and the serum phospholipid (PL) FA status in European adolescents and explored the percentage of variation in serum PL FA that could be attributed to dietary habits. Participants included 528 adolescents recruited in the HELENA Study. Dietary intake was assessed by two, self-administered, non-consecutive 24-h recalls. PL FA concentrations were measured in fasting venous serum samples. Reduced rank regressions were applied to examine the combined effect of food intakes. Results indicated that the variance in serum PL FA in adolescents, that could be explained by diet varied from 7.0 % for MUFA to 14.2 % for n-3FA. The variance in the long-chain n-3FA was mainly explained by fish intake but also by coffee and tea consumption. In conclusion this study indicated that dietary intake influences the serum PL FA status to a limited amount but that also other factors interfere. However, dietary intake is important as it is among those factors that could be modified. Furthermore, the results suggest that the overall dietary habits should be considered instead of only the consumption of single foods or nutrients, as the medium of the food or concomitant intake of foods and nutrients might interact and as such influence absorption or metabolism. 相似文献
93.
Tim D. Evans FCIWEM Per Andersson Åsa Wievegg Inge Carlsson 《Water and Environment Journal》2010,24(4):309-319
This paper reviews 15 years of sewage works' monitoring data to assess the effect of installing in-sink food waste disposers (FWD) and how these effects compare with the published scientific literature. For the first time, it has been possible to assess at full scale the load/cost transfer from solid-waste to wastewater management. Within a period of 10 years, 50% of households in the town of Surahammar in Sweden chose to have FWD installed as their means of managing their kitchen food waste. The drainage from the households feeds a single wastewater treatment works (WwTW) that comprises primary settlement, activated sludge, followed by chemical phosphate precipitation and mesophilic anaerobic digestion. The sewer system is separate but with overflow between foul and surface water in times of surcharge; the diameters and gradients of the sewers are unexceptional. This paper reviews the influent and biogas monitoring data for the years before installation started and the 10 years after the first peak of installations (by which time they had been installed in 30% of households). This provides a unique opportunity to verify the published research on FWD. The operational monitoring data are consistent with the already published research that FWD have little or no impact on water use, sewer blockages, vermin or wastewater treatment. The data are consistent with a hypothesis that in-sewer biological process acclimated to the change in wastewater composition and treated the dissolved and fine particulate load before it reached the WwTW. The digesters produced 46% more biogas than before FWD were installed (P=0.01). There was no significant increase in hydraulic load, or in the loading of BOD7, COD, N or NH4. As a result of Surahammar's overall waste strategy, not just the FWD, but the tonnage of waste to landfill from the municipality has also decreased from 3600 tonnes/year in 1996 to 1400 tonnes/year in 2007. 相似文献
94.
Tonsil samples from 139 slaughter pigs were examined for the presence of pathogenic Yersinia enterocolitica by enrichment procedures based on the standard method ISO 10273:2003. In addition, samples were tested by direct plating method to evaluate its efficiency compared to the enrichment culture methods and to quantify the level of contamination in porcine tonsils. In total, 52 samples (37.4%) were positive for pathogenic Y. enterocolitica, all belonging to bioserotype 4/O:3. Fifty out of the 52 positive samples (96.2%) were detected by direct plating. Enumeration showed an average concentration of 4.5 log10 CFU g−1 and 4.4 log10 CFU g−1 tonsil on Salmonella-Shigella-desoxycholate-calcium chloride (SSDC) and cefsulodin-irgasan-novobiocin (CIN) agar plates, respectively. The enrichment procedures recommended by the ISO 10273:2003 method were not optimal for the isolation of pathogenic Y. enterocolitica from pig tonsils: two days enrichment in irgasan-ticarcillin-potassium chlorate (ITC) broth resulted in an isolation rate of 84.6%, while 5 days enrichment in peptone-sorbitol-bile (PSB) broth recovered only 59.6% of positive samples. Reducing the enrichment time in PSB from 5 to 2 days resulted in a significantly higher recovery rate (94.2%) and might serve as an appropriate enrichment protocol for the isolation of pathogenic Y. enterocolitica from pig tonsils. Compared to enrichment culture methods, results based on direct plating can be obtained in a shorter time course and provide quantitative data that might be needed for further risk assessment studies. 相似文献
95.
Book reviewed in this article: Sensory Evaluation Techniques, 4th edition Authors: Morten C. Meilgaard, B. Thomas Carr and Gail Vance Civille 相似文献
96.
97.
Zica Valsan Inge Gavat Bogdan Sabac Oana Cula Ovidiu Grigore Diana Militaru Octavian Dumitru 《International Journal of Speech Technology》2002,5(3):259-268
The present paper describes the evolution of our work concerning the problem of speech recognition. Beginning with a classical hidden Markov model (HMM), we have investigated two ways to improve the performance of this basic structure. The first way was to realize a neuro-statistical hybrid by integrating a multilayer perceptron (MLP) as a posteriori probability estimator. The system was further refined by adding supplementary discriminative training (DT) based on the minimum classification error (MCE). Tests performed on a 15,000 isolated spoken-word database, showed an increase in the recognition rate from 92.2% for the HMM-based recognition system, to 94.7% for the HMM-MLP system, and then to 98.1% for the refined HMM-MLP-DT system. The second way to improve the classical HMM was to build a fuzzy-statistical hybrid, FHMM, based on a fuzzy similarity measure instead of the probabilistic measure specific to the usual statistical model. The benefits of the fuzzy measure introduction were evaluated on a vowel recognition task, and a decrease of approximately 3% in the error rate is reported. 相似文献
98.
The scientific basis for ergonomics recommendations for controls has usually not been related to active goal-directed use. The present experiment tests how different knob sizes and torques affect operator performance. The task employed is to control a pointer by the use of a control knob, and is as such an experimentally defined goal-directed task relevant to machine systems in general. Duration of use, error associated with use (overshooting of the goal area) and movement reproduction were used as performance measures. Significant differences between knob sizes were found for movement reproduction. High torques led to less overshooting as opposed to low torques. The results from duration of use showed a tendency that the differences between knob sizes were reduced from the first iteration to the second iteration. The present results indicate that the ergonomically recommended ranges of knob sizes might differently affect operator performance. 相似文献
99.
This letter is concerned with the problem of selecting the best or most informative dimension for dimension reduction and feature extraction in high-dimensional data. The dimension of the data is reduced by principal component analysis; subsequent application of independent component analysis to the principal component scores determines the most nongaussian directions in the lower-dimensional space. A criterion for choosing the optimal dimension based on bias-adjusted skewness and kurtosis is proposed. This new dimension selector is applied to real data sets and compared to existing methods. Simulation studies for a range of densities show that the proposed method performs well and is more appropriate for nongaussian data than existing methods. 相似文献
100.
TH Inge C Carmeci LJ Ohara WB Berquist JL Cahill 《Canadian Metallurgical Quarterly》1998,33(11):1614-1617
BACKGROUND: Intraoperative manometry is useful in performing Nissen fundoplication (NF) in children. Long-term clinical outcome information after use of this method is lacking. METHODS: A retrospective review of the outcomes of 62 consecutive NFs using intraoperative manometry was performed. The follow-up period was 3.4 years. Approximately half of the patients were neurologically normal (NN) and half were neurologically impaired (NI). All patients with gastroesophageal reflux disease (GERD) did not respond to an adequate trial of medical treatment. RESULTS: The NF was tailored to result in a twofold increase in the lower esophageal sphincter pressure (LESP) and a 75% increase in the LES length (LESL). An accelerated growth rate in 40% of "failure to thrive" (FTT) patients was demonstrated. Eighty-four percent of caregivers reported improved quality of life after NF. There was a twofold reduction in the number of hospital admissions and a sixfold reduction in total inpatient days for both NI and NN children. The early and late mortality rate was 13%, and the complication rate was similar to other series reported in the literature, with more complications occurring in NI patients. There was a 2% incidence of wrap herniation. An improvement in long-term outcomes after NF was seen in 89% of NN children and over half of NI patients. CONCLUSIONS: Intraoperative manometry is useful in standardizing the tightness of the wrap in NF. There was a low incidence of complications, dysphagia, recurrent emesis, and GERD in this series. Long-term outcomes using this technique were deemed very good based on caregivers' responses. 相似文献