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11.
This study assessed the meaning of just‐about‐right (JAR) categories when used with a 5‐point intensity scale. The panelists comprised both consumer and in‐house respondents. The JAR categories have various meanings as perceived by the respondents: “prefer product,”“very good,”“I like the product,”“like it very much,”“highly favorable,”“high acceptability,”“desirable like the product,”“best for the situation” and “correct.” Thus, the JAR meanings invoke preference and acceptability. This article presents two additional analyses to help the product tested. One method of analysis divides below‐JAR deviation from the above‐JAR deviation, with standard statistical procedures applied in each data set. The second method introduces the signal‐to‐noise ratio statistic for analyzing the relation of JAR to overall liking. Both analytic methods provide new ways to look at the JAR data, especially with respect to hedonics and product improvement.  相似文献   
12.
This paper considers “importance” of sensory attributes from the consumer point of view, with emphasis on processed seafood. There are three key measures of importance. Attitudinal importance measures what consumers think to be important and refers to general opinions about the category. Sensory system importance measures how strongly different sensory inputs (e.g., appearance, aroma, taste, texture) “drive” overall liking, and show the key sensory inputs to which consumers attend. Attribute level importance measures the relation between sensory intensity and overall liking for each attribute. It shows which specific attributes drive liking, how liking varies with the specific sensory attribute, and whether (and at what sensory level) there exists an optimal level.  相似文献   
13.
Liking is a key measure for applied product development. All too often, however, the liking attributes are simply reported, but other than analyzing overall liking ratings no other analysis is done on the ratings. Much more remains for applied product testers to learn from these liking attributes. This paper presents a detailed analysis of the interrelations among different liking attributes for apple pie. It shows that panelists discriminate among samples using different liking scales, but many of these scales correlate with each other creating a great deal of redundancy in the list of attributes. Factor analysis reveals one major dimension for liking of the entire pie, and three dimensions for liking of slices. A different way of analysis shows potentially more utility for developers. A linear model relating overall liking to each attribute liking reveals different slopes, suggesting different importance levels for the attribute liking scales. Furthermore, one can create an integrated liking model. The liking ratings can be combined into a single, overall product model, allowing the researcher to understand how changes in one liking attribute simultaneously affect all other liking attributes.  相似文献   
14.

ABSTRACT

Using the observational analysis of two different foods as test products, this note examined some interesting findings that emerge when the just‐about‐right (JAR) scale was placed after the overall liking rating, and before the preference ranking. The JAR data appeared to be statistically uncorrelated with the overall rating scales. First, this fortuitous observation from several studies suggests that the JAR scale can play a diagnostic role to determine how the consumer feels about changing the product. Second, the statistical analysis of the JAR ratings (e.g., bipolar nature of the JAR scale, its skewness and kurtosis) all suggest that the appropriate measure is %JAR, an incidence metric, rather than scale average, ought to be used both to report the results, and to create models relating to the JAR versus sensory magnitude or versus liking, respectively.

PRACTICAL APPLICATIONS

The results of the present analysis suggest that overall acceptance/liking can be the last question in the questionnaire design. That location is very important for the sensory analysis of foods eaten over time and then rated, as well as personal care and cosmetic studies where the products are used over time periods, and where the true evaluation of performance ought to be made at the end of the trial. In these long‐term uses, overall liking is generally the last question given at the end of the time period of product evaluation. The facts that the just‐about‐right (JAR) scales are independent of this final overall liking rating suggest that the integrity of the overall evaluation and usefulness of JAR as diagnostics will not be compromised.  相似文献   
15.
1. In lentic freshwater habitats, the composition of animal assemblages shifts along a gradient from temporary to permanent basins. When habitats with different degrees of permanence are at the scale of the home range of species, they constitute alternatives in terms of energy acquisition through feeding. 2. In this context, previous studies showed an advantage of metamorphic over paedomorphic tiger salamanders (Ambystoma tigrinum) in temporary ponds which are only available to metamorphs. The aim of this study was to establish whether salamanders obtain similar benefits in ponds that do not differ in water permanence and whether salamanders shifted from detrimental to advantageous ponds. To this end, we determined the feeding habits, body condition and movement patterns of the two morphs in a complex of four permanent and four temporary ponds. 3. Consistent with previous studies, metamorphs consumed higher‐quality diets than paedomorphs in term of energy intake. However, these differences occurred because metamorphs consumed fairy shrimp in a single temporary pond. Individual movement patterns confirmed that most of the metamorphs used different aquatic habitats both within and between years and that most of them moved from permanent ponds for breeding towards the most profitable temporary pond in terms of foraging. 4. These results indicate that habitat selection by salamanders is optimal in term of energy intake in metamorphs that use high quality ponds independently of hydroperiod. It seems that both spatial and temporal variation can influence the relative foraging success of each morph.  相似文献   
16.
While there is currently intense effort to examine the 13C signal of CO2 evolved in the dark, less is known on the isotope composition of day‐respired CO2. This lack of knowledge stems from technical difficulties to measure the pure respiratory isotopic signal: day respiration is mixed up with photorespiration, and there is no obvious way to separate photosynthetic fractionation (pure ci/ca effect) from respiratory effect (production of CO2 with a different δ13C value from that of net‐fixed CO2) at the ecosystem level. Here, we took advantage of new simple equations, and applied them to sunflower canopies grown under low and high [CO2]. We show that whole mesocosm‐respired CO2 is slightly 13C depleted in the light at the mesocosm level (by 0.2–0.8‰), while it is slightly 13C enriched in darkness (by 1.5–3.2‰). The turnover of the respiratory carbon pool after labelling appears similar in the light and in the dark, and accordingly, a hierarchical clustering analysis shows a close correlation between the 13C abundance in day‐ and night‐evolved CO2. We conclude that the carbon source for respiration is similar in the dark and in the light, but the metabolic pathways associated with CO2 production may change, thereby explaining the different 12C/13C respiratory fractionations in the light and in the dark.  相似文献   
17.
Three weeks after hypophysectomy mitosis and DNA synthesis are absent in the lens of the leopard frog ( Rana pipiens ). By labeling germinative zone cells in their last DNA synthetic period we were able to follow them in the absence of further proliferation. By this means it has been demonstrated that migration of epithelial cells to the equator of the lens is stopped. Based on indirect measurements it seems that lens fiber formation also ceases. A correlation coefficient of 0.86 was computed between average labeling index and average distance migrated. In hypophysectomized animals the correlation coefficient between time and migration was 0.02 while in intact animals it is 0.87.  相似文献   
18.
SYNOPSIS. The eyespot of the zoospore of Tetracystis excentrica (a green alga) has been studied by light and electron microscopy. In Tetracystis the eyespot consists of about 110 osmiophilic granules which form a plate in the anterior third of the cell. The granules are about 80 Å in diameter and are found in the outermost portion of the chloroplast; they commonly show hexagonal close packing and a hexagonal shape. The granules are confined positionally by the chloroplast envelope and an inner thylakoid. The plasmalemma over the eyespot is thickened and is separated from the chloroplast envelope by a 50 mμ space. The eyespot of Tetracystis is compared with others reported in the literature and the possible functional significance of these studies is discussed. The possibility that the eyespot plate in Tetracystis serves as a shading device rather than the primary photoreceptor is considered.  相似文献   
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