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71.
Marise KinnearHenriëtte L. de Kock 《Food quality and preference》2011,22(4):340-345
Repeated exposure to sports drinks with different acidulants added at equal sour concentrations led to hedonic adjustment when consumers (n = 128) evaluated a Lemon & Lime flavoured sports drink over a period of 14 days. Consumer preferences after repeated exposure could not have been predicted from the initial small sample single exposure consumer taste test. Product exposure and time on trial influenced the preferences of consumers. Products that were initially preferred became less preferred after 14 days. The findings of this study challenge the validity of sensory evaluation test strategies that rely on single exposure testing to predict long term consumer preferences. 相似文献
72.
Relating sensory profiles of canned amaranth (Amaranthus cruentus), cleome (Cleome gynandra), cowpea (Vigna unguiculata) and Swiss chard (Beta vulgaris) leaves to consumer acceptance
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73.
I. I. Courter T. M. Garrison T. J. Kock R. W. Perry D. B. Child J. D. Hubble 《河流研究与利用》2016,32(10):1999-2008
The influence of streamflow on survival of emigrating juvenile Pacific salmonids Oncorhynchus spp. (smolts) is a major concern for water managers throughout the northeast Pacific Rim. However, few studies have quantified flow effects on smolt survival, and available information does not indicate a consistent flow–survival relationship within the typical range of flows under management control. In the Yakima Basin, Washington, the potential effects of streamflow alterations on smolt survival have been debated for over 20 years. Using a series of controlled flow releases from upper basin reservoirs and radiotelemetry, we quantified the relationship between flow and yearling Chinook salmon smolt survival in the 208 km reach between Roza Dam and the Yakima River mouth. A multistate mark–recapture model accounted for weekly variation in flow conditions experienced by tagged fish in four discrete river segments. Smolt survival was significantly associated with streamflow in the Roza Reach [river kilometre (rkm) 208–189] and marginally associated with streamflow in the Sunnyside Reach (rkm 169–77). However, smolt survival was not significantly associated with flow in the Naches and Prosser Reaches (rkm 189–169 and rkm 77–3). This discrepancy indicates potential differences in underlying flow‐related survival mechanisms, such as predation or passage impediments. Our results clarify trade‐offs between flow augmentation for fisheries enhancement and other beneficial uses, and our study design provides a framework for resolving uncertainties about streamflow effects on migratory fish survival in other river systems. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
74.
H.-A. Crostack K.-H. Kock H.-D. Steffens 《Materialwissenschaft und Werkstofftechnik》1981,12(5):160-167
Separation of Acoustic Emission Signals by Computerized Analyses Features extracted from acoustic emission signals by means of different analysis methods can be evaluated by the application of pattern recognition computer programs. By these methods it can be established, whether the employed features – maximum amplitude, signal rise time, pulse sum, pulse area, pulse energy and mean amplitude as well as simple characteristics of frequency spectra – are capable to distinguish acoustic emission signals or whether combinations of features lead to better results when single features fail. The efficiency of different analyses and the pattern recongnition programs is examined by four simulated types of signals. According to the employed analysis method there are distinct differences regarding the separation of acoustic emission. However, by applying feature combinations signal groups not separable by single analysis methods can be distinguished. 相似文献
75.
CB Vernooij RF Kruitwagen P Rodrigus HC Kock HW Feyen 《Canadian Metallurgical Quarterly》1997,67(3):325-327
The development of a hematometra after radiotherapy for cervical carcinoma is often related to recurrent disease. We present two cases in which a hematometra developed during the use of estrogen replacement therapy. This development was related to regained endometrial activity in combination with fibrosis and obliteration of the upper vagina and/or cervix. In one patient a dilatation and curettage could be performed; in the other a hysterectomy was necessary in order to exclude recurrent disease. These two cases show once more that endometrium can regain its proliferative activity after radiotherapy for cervical cancer. Estrogen replacement therapy in these patients should include the use of a progestagen agent in order to avoid continuous unopposed endometrial stimulation. In the absence of progesterone withdrawal bleeding the uterine cavity should be routinely examined for the development of a hematometra. 相似文献
76.
P. Venter J. L. F. Kock G. Sravan Kumar A. Botha D. J. Coetzee P. J. Botes R. K. Bhatt J. R. Falck T. Schewe S. Nigam 《Lipids》1997,32(12):1277-1283
Various fatty acids were fed to the yeast Dipodascopsis uninucleata UOFS Y 128, and the extracted samples were analyzed for the accumulation of 3-hydroxy metabolites with the help of electron
impact gas chromatography-mass spectrometry. Fatty acids containing a 5Z,8Z-diene system (5Z,8Z,11Z-eicosatrienoic, 5Z,8Z,11Z,14Z-eicosatetraenoic, and 5Z,8Z,11Z,14Z,17Z-eicosapentaenoic acids) yielded the corresponding 3-hydroxy-all-Z-eicosapolyenoic acids. Moreover, linoleic acid (9Z,12Z-octadecadienoic acid) and 11Z,14Z,17Z-eicosatrienoic acid were converted to the 3-hydroxylated metabolites of shorter chain length, e.g., 3-hydroxy-5Z,8Z-tetradecadienoic acid and 3-hydroxy-5Z,8Z,11Z-tetradecatrienoic acid, respectively. In contrast, no accumulation of a 3-hydroxy metabolite was observed with oleic acid
(9Z-octadecenoic acid), linolelaidic acid (9E,12E-octadecadienoic acid), γ-linolenic acid (6Z,9Z,12Z-octadecatrienoic acid), and eicosanoic acid as substrate. These findings pinpoint that the 3-hydroxylation of a fatty acid
in Dipodascopsis uninucleata requires a 5Z,8Z-diene system either directly or following initial incomplete β-oxidation. Following analysis of the enantiomer composition,
the arachidonic acid metabolite was identified as 3R-hydroxy-5Z,8Z,11Z,14Z-eicosatetraenoic acid, which rules out a normal β-oxidation as biosynthetic route to this new class of oxylipins. 相似文献
77.
Electrodialysis (ED) was applied to concentrate brine solutions of various concentrations — similar to effluentsfrom the desalination of brackish and industrial water — to about 20%. The consequent reduction in effluent volumes would facilitate a reduction in disposal costs. The energy requirement for concentrating solutions from 70 to 300 mN (0.4-1.8%) to 3.9 N (20%) was in the range 1.5-7.1 kWh/m3, in contrast to approximately 25 kWh/m3 by thermal evaporation. With the aim of preventing precipitation of CaSO4 on the membranes, laboratory-scale ED experiments were carried out on solutions of different compositions to determine the conditions that would lead to the precipitation of excess gypsum on gypsum seeds in a separate precipitator. The results were then applied in a pilot-scale ED unit in which the brine that circulated through the ED brine cells passed through a separate CaSO, precipitator containing gypsum seeds. 相似文献
78.
Ned Kock 《Information Systems Journal》2019,29(3):674-706
Partial least squares (PLS) methods possess desirable characteristics that have led to their extensive use in the field of information systems, as well as many other fields, for path analyses with latent variables. Such variables are typically conceptualized as factors in structural equation modelling (SEM). In spite of their desirable characteristics, PLS methods suffer from a fundamental problem: Unlike covariance‐based SEM, they do not deal with factors, but with composites, and as such do not fully account for measurement error. This leads to biased parameters, even as sample sizes grow to infinity. Anchored on a new conceptual foundation, we discuss a method that builds on the consistent PLS technique and that estimates factors, fully accounting for measurement error. We provide evidence that this new method shares the property of statistical consistency with covariance‐based SEM but, like classic PLS methods, has greater statistical power. Moreover, our method provides correlation‐preserving estimates of the factors, which can be used in a variety of other tests. For readers interested in trying it, the new method is implemented in the software WarpPLS. Our detailed discussion should facilitate the implementation of the method in any numeric computing environment, including open source environments such as R and GNU Octave. 相似文献
79.
Angler Harvest,Hatchery Return,and Tributary Stray Rates of Recycled Adult Summer Steelhead Oncorhynchus mykiss in the Cowlitz River,Washington
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Hatchery ‘recycling’ programs have been used to increase angling opportunities by re‐releasing fish into a river after they returned to a hatchery or fish trap. Recycling is intended to increase opportunities for fishermen, but this strategy could affect wild fish populations if some recycled fish remain in the river and interact with wild fish populations. To quantify hatchery return and angler harvest rates of recycled steelhead, we conducted a 2‐year study on the Cowlitz River, Washington. A total of 1051 steelhead were recycled, including 218 fish that were radio‐tagged. Fates of recycled steelhead were similar between years: 48.4% returned to the hatchery, 19.2% were reported captured by anglers, and 32.4% remained in the river. A multistate model quantified the effects of covariates on hatchery return and angler harvest rates, which were positively affected by river discharge and negatively affected by time since release. However, hatchery return rates increased and angler harvest rates decreased during periods of increasing discharge. A total of 21.1% (46 fish) of the radio‐tagged steelhead failed to return to the hatchery or be reported by anglers, but nearly half of those fish (20 fish) appeared to be harvested and not reported. The remaining tagged fish (11.9% of the radio‐tagged population) were monitored into the spawning period, but only five fish (2.3% of the radio‐tagged population) entered tributaries where wild steelhead spawning occurs. Future research focused on straying behaviour, and spawning success of recycled steelhead may further advance the understanding of the effects of recycling as a management strategy. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
80.
We present a Penning discharge as a possible radiometric transfer standard source in the vacuum UV, primarily in the spectral region below 20 nm. Following the concept of Finley et al., we have designed a Penning source using NdFeB permanent magnets. Emphasis was put on simple operation, quick electrode exchangeability, and easy source readjustment. The radiant intensities of the emission lines from different ionization stages of both buffer gas atoms and atoms sputtered from the cathodes have been studied in various discharge conditions. For selected Al and buffer gas emission lines we determined the absolute radiant intensities by a comparison with the calculable spectral radiant power of the Berlin Electron Storage Ring. A comparison with data from our hollow-cathode transfer standard source is given. 相似文献