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981.
This paper introduces a research methodology that adds sophistication to the innovation process for agricultural goods. In recognition of the importance of innovation for the long‐term success of firms and the need for market analysis that goes beyond traditional sensory and consumer preference testing, it is demonstrated how to measure the monetary value consumers place on new market goods. In experimental markets, New Zealand (NZ) consumers were willing to pay on average approximately NZ$0.44 per 100 g to exchange the common green‐fleshed Hayward variety for a new‐to‐market red‐ and yellow‐fleshed kiwifruit variety. At the time of the study this was equivalent to a 179% retail price premium. Knowledge that this new variety was not genetically modified increased the price premium to 240%. These results were elicited from convenience samples and should be treated with caution if used as the sole basis for price setting. Copyright © 2005 Society of Chemical Industry 相似文献
982.
Sara R Jaeger Karen L Rossiter Karen Lau 《Journal of the science of food and agriculture》2005,85(3):480-488
To explore how consumers perceive novel and familiar fruit, repertory grid interviews were carried out with 60 New Zealand women. Participants described their perceptions of nine fruit varying in familiarity. The data analysis established a two‐dimensional stimuli space that separated samples with respect to familiarity and the amount of preparation required. Fruit that was familiar was characterised as being well liked, easily available in shops and by a number of different use situations. The primary association with novel fruit was that it was expensive. The participants could not readily think of use situations for fruit they were unfamiliar with. Consumers were separated into groups according to the trait of food neophobia, which pertains to an individual's stable propensity to approach or avoid novel foods. When comparing the most neophobic (n = 14; avoids novel foods) and most neophilic (n = 14; approaches novel foods), individuals perceptual differences were uncovered pertaining to which of the fruit were considered novel and to the suitability of some usage situations (cooking and for children). This finding contributed to the growing evidence of the relationship between food neophobia and consumers' everyday food‐related behaviour. Copyright © 2004 Society of Chemical Industry 相似文献
983.
Just Noticeable Differences and Weber Fraction of Oral Thickness Perception of Model Beverages
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Sara Camacho Mathilde Dop Cees de Graaf Markus Stieger 《Journal of food science》2015,80(7):S1583-S1588
Rheological properties of beverages contribute considerably to texture perception. When developing new beverages, it is important to have knowledge on the smallest differences of viscosity which a consumer can discriminate. Thickness is the sensory attribute most commonly used to describe the viscosity of beverages. The aim of this study was to determine the Just Noticeable Differences (JNDs) of oral thickness perception and the Weber fraction (K) of Newtonian model stimuli (maltodextrin solutions). JNDs were determined using the method of constant stimuli with 5 reference stimuli ranging in viscosity from 10 to 100 mPa?s. JNDs increased with increasing viscosity of the reference stimulus. The Weber fraction (K) for oral thickness perception of model beverages was K = 0.26 for the studied viscosity range. The Weber fraction for oral thickness perception is comparable to Weber fractions reported in literature for perception of kinesthetic food firmness and spreadability, creaminess, sourness, and bitterness perception. This demonstrates that the human sensitivity towards oral discrimination of thickness of liquid stimuli is comparable to the human sensitivity towards discrimination of specific texture properties and specific taste stimuli. 相似文献
984.
Claudia Paoletti Andreas Heissenberger Marco Mazzara Sara Larcher Emanuele Grazioli Philippe Corbisier Norbert Hess Gilbert Berben Peter S. Lübeck Marc De Loose Gillian Moran Christine Henry Carlo Brera Imma Folch Jaroslava Ovesna Guy Van den Eede 《European Food Research and Technology》2006,224(1):129-139
The reliability of analytical testing is strongly affected by sampling uncertainty. Sampling is always a source of error and the aim of “good” sampling practice is to minimize this error. Generally the distribution of genetically modified (GM) material within lots is assumed to be random in order to use binomial distribution to make inferences. This assumption was never verified in practice and no experimental data investigating the distribution of genetically modified organisms (GMOs) exist. The objectives of the KeLDA project were: (1) to assess the distribution of GM material in soybean lots (2) to estimate the amount of variability of distribution patterns among lots. The GM content of 15 soybean lots imported into the EU was estimated (using real-time PCR methodology) analyzing 100 increment samples systematically sampled from each lot at predetermined time intervals during the whole period of off-loading. The distribution of GM material was inferred by the one-dimensional (temporal) distribution of contaminated increments. All the lots display significant spatial structuring, indicating that randomness cannot be assumed a priori. The evidence that the distribution of GM material is heterogeneous highlights the need to develop sampling protocols based on statistical models free of distribution requirements. 相似文献
985.
986.
987.
Miguel Angel Barcala-Montejano Angel Antonio Rodriguez-Sevillano Maria Elena Rodriguez-Rojo Sara Morales-Serrano 《机械工程与自动化:英文版》2014,(5):412-421
This paper presents an experimental and systematic investigation about how geometric parameters on a biplane configuration have an influence on aerodynamic parameters. This experimental investigation has been developed in a two-dimensional approach. Theoretical studies about biplanes configurations have been developed in the past, but there is not enough information about experimental wind tunnel data at low Reynolds number. This two-dimensional study is a first step to further tridimensional investigations about the box wing configuration. The main objective of the study is to find the relationships between the geometrical parameters which present the best aerodynamic behavior: the highest lift, the lowest drag and the lowest slope of the pitching moment. A tridimensional wing-box model will be designed following the pattern of the two dimensional study conclusions. It will respond to the geometrical relationships that have been considered to show the better aerodynamic behavior. This box-wing model will be studied in the aim of comparing the advantages and disadvantages between this biplane configuration and the plane configuration, looking for implementing the box-wing in the UAV's field. Although the box wing configuration has been used in a small number of existing UAV, prestigious researchers have found it as a field of high aerodynamic and structural potential. 相似文献
988.
Purpose
To compare the current optometric practices and attitudes in the management of keratoconus patients in the UK and Spain.Methods
An online survey (adapted to optometric practices) was distributed via a newsletter emailed by various professional organizations in the UK and Spain.Results
Four hundred and sixty-four practitioners (126 in the UK; 338 in Spain) who prescribed gas permeable GP contact lenses (CLs) more than once per month (54.8% of UK practitioners and 28.1% of practitioners in Spain; p < 0.01) responded to the questionnaire. A combination of multiple factors is considered necessary in the keratoconus detection (79.4% in the UK, 75% in Spain; p = 0.68), and the use of classification criteria is considered relevant (67.5% in the UK, 70.7% in Spain; p = 0.49). There is a high consensus on the consideration that GP CL fitting is more difficult in keratoconus (79.4% in the UK, 80.5% in Spain; p = 0.79) requiring more diagnostic lenses (3.2 ± 1.4 and 3.4 ± 1.2 in the UK and Spain, respectively; p = 0.72) than are necessary for healthy eyes. Using corneal topography is uncommon from both countries (38.1% in the UK, 59.8% in Spain; p < 0.01), with a similar ophthalmologist referral pattern (at initial diagnosis, 50% in both the UK and Spain; p = 1.00). Few cases of co-management with ophthalmologists were noted (no co-management reported by 60.3% in the UK and 72.8% in Spain, p = 0.01).Conclusion
This study provides initial observations and evidence regarding keratoconus management by optometrists in the UK and Spain and shows similarity in the professional practices and attitudes of practitioners in these two countries. 相似文献989.
990.
Leonhardt SD Form S Blüthgen N Schmitt T Feldhaar H 《Journal of chemical ecology》2011,37(10):1117-1126
Colonies of the stingless bee Tetragonilla collina frequently occur in unusually high densities and in direct neighborhood (nest aggregations), in rainforests of Southeast
Asia. To investigate whether close relatedness and/or similar chemical profiles facilitate the co-occurrence of multiple T. collina colonies, we investigated aggressive behavior, genetic relatedness and cuticular hydrocarbon (CHC) profiles within and between
colonies and nest aggregations. Although 17 out of 19 colonies within aggregations were largely unrelated, intraspecific aggression
between different colonies was basically absent both within and among aggregations. This lack of aggression should favor social
parasitism and hence the occurrence of unrelated individuals within a colony. However, low within-colony relatedness was found
in only five out of 19 colonies where it may be explained by queen turnover or the occurrence of foreign workers. CHC profiles
of colonies within and among aggregations were statistically different. However, many workers could chemically not be assigned
to their maternal colony, indicating considerable overlap among colonies in odor profiles of workers. Moreover, odor profiles
tended to be more similar within than among aggregations, although most colonies were unrelated. Thus, CHC profiles were a
poor indicator of relatedness in T. collina. The lack of correlation between relatedness and chemical similarity in T. collina may be explained by the incorporation of resin-derived terpenes in their CHC profiles. The composition of these terpenes
was highly similar among colonies, particularly within aggregations, hence potentially decreasing chemical distinctiveness
and increasing behavioral tolerance. 相似文献