USING ANDERSON'S STATISTIC TO COMPARE DISTRIBUTIONS OF CONSUMER PREFERENCE RANKINGS

Anderson's statistic, which compares distributions of ranks, is generalized to cope with tied rankings. A simple example is given to illustrate the calculations involved. In market research work it is often important to compare distributions as well as mean values. Comparison of distributions can indicate either market segmentation or product variability.     

CONSUMER ATTITUDES AND OPINIONS TOWARD FUNCTIONAL FOODS: A FOCUS GROUP STUDY

Acceptance of foods with specific health characteristics depends largely on the consumers' opinion. The objective of this work was to investigate Spanish consumers' opinions, attitudes and beliefs regarding functional foods in general, and one of the most popular foods, yogurt, in particular. Six consumer focus group interviews were conducted, involving a total of 59 participants. Each group profile was chosen to either complement or contrast the other groups according to previously established criteria (gender, age and educational level). The youngest consumers (18–30 years old) proved, in general, to have a fairly negative attitude toward these types of products, although this attitude varied according to the type of food. For the consumers participating in this study, the most acceptable functional foods were low-fat foods and some fermented dairy products. Purchase and consumption of yogurt were more dependent on its sensorial qualities and its price than on the nutritional information printed on the label.

PRACTICAL APPLICATIONS

The influence of attitudes, beliefs and opinions on food choice and purchase is specially important in the acceptance of some types of foods (organic or ecological, genetically modified or functional) that are presented to the consumer as a possible alternative to the conventional foods. The application of focus groups can help not only in explaining consumer behavior, but also in designing more effective nutritional education rules and products that satisfy consumer needs and expectations.     

花生根瘤菌的抗逆性初步研究*

对３９株花生根瘤菌（其中６株为引进菌株）和９株参比菌株进行干旱、ＮａＣｌ、ｐＨ及低温的耐受性实验。结果表明我国花生根瘤菌资源中存在着耐盐、酸较强的菌株,且耐受性水平差异较大;在８℃条件下供试菌株未见生长;花生根瘤菌有着比大豆根瘤菌更强的抗干旱能力,抗干旱能力同耐盐能力之间没有明显的关系。另外,菌株的抗逆性同共生特性、分离地之间也未见有明显的关系。     

DEVELOPMENT OF A LEXICON FOR THE DESCRIPTION OF PEANUT FLAVOR

A lexicon of terms to describe desirable as well as undesirable flavors in peanuts has been developed. The lexicon and an intensity rating scale was developed by a 13 member panel of flavor and peanut specialists representing industry and the USDA-Agricultural Research Service. This system is intended to provide definitive, common terminology for use in communicating differences in peanut flavor variables among all phases of peanut research and industry.     

OPTIMIZATION OF A CHOCOLATE PEANUT SPREAD USING RESPONSE SURFACE METHODOLOGY (RSM)

Response surface methodology was used to optimize formulations of chocolate peanut spread. Thirty-six formulations with varying levels of peanut (25-90%), chocolate (5-70%) and sugar (5-55%) were processed using a three-component constrained simplex lattice design. The processing variable, roast (light, medium, dark) was also included in the design. Response variables, measured with consumers (n = 60) participating in the test, were spreadability, overall acceptability, appearance, color, flavor, sweetness and texture/mouthfeel, using a 9-point hedonic scale. Regression analysis was performed and models were built for each significant (p < 0.01) response variable. Contour plots for each attribute, at each level of roast, were generated and superimposed to determine areas of overlap. Optimum formulations (consumer acceptance rating of ≥ 6.0 for all attributes) for chocolate peanut spread were all combinations of 29-65% peanut, 9-41% chocolate, and 17-36% sugar, adding up to 100%, at a medium roast. Verification of two formulations indicated no difference between predicted and observed values.     

USING QUANTITATIVE PCR TO DETERMINE THE DISTRIBUTION OF A SEMICRYPTIC BENTHIC DIATOM,NAVICULA PHYLLEPTA (BACILLARIOPHYCEAE)1

Evidence has accumulated during the last decade showing that many established diatom morpho‐species actually consist of several semicryptic or truly cryptic species. As these species are difficult or even impossible to differentiate by microscopic analysis, there is virtually no information on how they behave in natural environments. In this study, we developed a quantitative real‐time PCR (qPCR) assay using TaqMan probes^® targeted to the internal transcribed spacer 1 (ITS1) to assess the spatial distribution and seasonal dynamics of an important component of the microphytobenthos of intertidal sediments. Navicula phyllepta Kützing is a brackish‐marine morpho‐species with a cosmopolitan distribution. Axenic clones of this species were isolated from natural assemblages of benthic diatoms at different intertidal stations in the Westerschelde estuary (The Netherlands). At least two distinct semicryptic species of N. phyllepta were present, as shown by differences in the quantity of DNA per cell, the ITS1 sequences and the copy number of ITS per cell. DNA and chl a concentrations extracted from sediment surface samples were closely correlated, showing that the DNA used for subsequent analysis mostly belonged to the microalgal community. The results of real‐time qPCR from sites throughout the estuary and over several seasons agreed well with microscopic counts. Additionally, the seasonal pattern of the two forms of N. phyllepta showed an overlapping, but unique distribution along the estuary.     

A QUANTITATIVE SAMPLER FOR SUBMERGED AQUATIC MACROPHYTES

SUMMARY

A simple rotary sampler, capable of quantitatively harvesting submerged aquatic macrophytes is described. The sampler can be operated from a boat and consists of a central rod with a specially designed cutting blade at the base, and collecting hooks to catch the cut material. The values obtained with this sampler were not significantly different (at the 95% level of probabality) from those obtained by manual cutting underwater. The rotary sampler has great advantages in terms of time, ease of positioning, and effort over hand cutting.     

MAPPING THE EFFECT OF INFORMATION ABOUT ANIMAL WELFARE ON CONSUMER LIKING AND WILLINGNESS TO PAY FOR YOGURT

Preference mapping identified different groups of consumers on the basis of their disconfirmations (occurring when the product is either better or worse than expected) and assimilations (occurring when actual liking [L] moves toward the expectations). The negative disconfirmation of a group of consumers (Group 1) was based on the information about animal welfare (the products were worse than expected because the information about animal welfare induced high expectations), whereas in Group 2 the sensory properties of the products prevailed in orienting consumer disconfirmation (products were worse than expected because the sensory properties of low-fat yogurt were disliked). The map of assimilation showed that consumers from Group 1 had higher assimilation for plain yogurt associated with high welfare standards as a consequence of the high discrepancy between blind and expected L for these products. A similar behavior was observed for Group 2 (higher discrepancy between blind and expected L corresponding to higher assimilation for low-fat yogurt paired with high welfare standards).

PRACTICAL APPLICATIONS

Consumers based their choices both on sensory properties (plain yogurts were preferred to low-fat yogurts) and on information about animal welfare (products associated with high welfare standards were preferred to the others). Preference mapping was able to identify groups of consumers behaving differently, as compared with the general trend, on the basis of their disconfirmations and assimilations.
Consumer willingness to pay reflected the hedonic behavior, thus validating the auction procedure for food liking evaluation purposes and providing a useful tool to obtain information about the real value (i.e., in monetary terms) consumers give to animal welfare.     

THE ECO‐EVOLUTIONARY RESPONSES OF A GENERALIST CONSUMER TO RESOURCE COMPETITION

This article explores the combined evolutionary and ecological responses of resource uptake abilities in a generalist consumer to exploitative competition for one resource using a simple 2‐resource model. It compares the sizes of ecologically and evolutionarily caused changes in population densities in cases where the original consumer has a strong or a weak trade‐off in its abilities to consume the two resources. The analysis also compares the responses of the original species to competition when the competitor's population size is or is not limited by the shared resource. Although divergence in resource use traits in the resident generalist consumer is expected under all scenarios when resources are substitutable, the changes in population densities of the resources and resident consumer frequently differ between scenarios. The population of the original consumer often decreases as a result of its own adaptive divergence, and this decrease is often much greater than the initial ecological decrease. If the evolving consumer has a strong trade‐off, the overlapped resource increases in equilibrium population density in response to being consumed by a generalist competitor. Some of these predictions differ qualitatively in alternative scenarios involving sustained variation in population densities or nutritionally essential resources.     

USING HIGH-LEVEL CONSUMER-RESEARCH METHODS TO CREATE A TOOL-DRIVEN GUIDEBOOK AND DATABASE FOR PRODUCT DEVELOPMENT AND MARKETING

We present aspects and data for a tool‐driven database for marketing and product development, which are publicly accessible. The objective is to create a method whereby knowledge of concepts and products can be archived using overviews of a specific product category. The first phase of the database comprises systematic analysis of product concepts, which contain elements dealing both with features and emotions. The concept phase provides an idea about responses to statements about product features, along with responses to emotional elements and brands. The second phase comprises an analysis of the competitive frame of products, even before systematic product development is initiated. This second phase identifies expected and thus reasonable ranges of product‐sensory features, levels of acceptance of typical products, relations between liking and sensory attributes and segmentation of sensory preferences. Together, the two phases provide a guide to product developers new in a category, archive current knowledge and provide a sourcebook for marketers and developers alike, which is accessible using research tools. The two phases allow product development to become more scientific, more based on common experience rather than individual expertise and thus more efficient, without compromising corporate knowledge of specific ingredients, processes or business opportunities.     

A RADIOIMMUNOASSAY FOR MYELIN BASIC PROTEIN AND ITS USE FOR QUANTITATIVE MEASUREMENTS

—A specific radioimmunoassay (RIA) for myelin basic protein is described which is sensitive to 10⁻⁹ g of basic protein. The amount of basic protein detected in isolated myelin by the RIA and by SDS-gel electrophoresis and spectrophotometric quantitation agree to within experimental error. In contrast to isolated myelin, the major portion of the basic protein in fresh tissue is not accessible to its antibody. It is shielded from its antibody in a complex which is disrupted by heat, organic solvents, and various detergents. Maximum antibody binding was obtained with tissue heated to 100°C for 10 min. It is possible to calculate that the RIA quantitatively detects basic protein in boiled tissue. Boiled adult rat brain contains approximately 2·5 μg of basic protein/mg wet wt of cerebral cortex. The antibody to basic protein has no capacity to bind non-neural tissues.     

A NOVEL PROTECTING STRATEGY FOR INTERNUCLEOSIDIC PHOSPHATE AND PHOSPHOROTHIOATE GROUPS

The utility of 2–(N–isopropyl–N–anisoylamino)ethyl group for protection of internucleosidic phosphate linkages in oligonucleotide synthesis was studied. The group demonstrated high coupling yields, favorable deprotection kinetics and a high hydrolytic stability of phosphoramidite building blocks. The mechanism of deprotection was established using a model phosphate triester.     

A METHOD FOR THE QUANTITATIVE ESTIMATION OF CYTOPLASMIC STRUCTURES

A sampling procedure and calculations are described by which electron micrographs of cytoplasmic structures may be quantitatively analyzed. The relative areas occupied by formed bodies and by the "membrane space," the remainder of the cytoplasm, are evaluated. A method for making a measurement of the quantity of endoplasmic reticulum or other membrane profiles is described. The technic and results are illustrated with normal rat liver cells.     

RECOMMENDATIONS FOR USING MSBAYES TO INCORPORATE UNCERTAINTY IN SELECTING AN ABC MODEL PRIOR: A RESPONSE TO OAKS ET AL.

Prior specification is an essential component of parameter estimation and model comparison in Approximate Bayesian computation (ABC). Oaks et al. present a simulation‐based power analysis of msBayes and conclude that msBayes has low power to detect genuinely random divergence times across taxa, and suggest the cause is Lindley's paradox. Although the predictions are similar, we show that their findings are more fundamentally explained by insufficient prior sampling that arises with poorly chosen wide priors that critically undersample nonsimultaneous divergence histories of high likelihood. In a reanalysis of their data on Philippine Island vertebrates, we show how this problem can be circumvented by expanding upon a previously developed procedure that accommodates uncertainty in prior selection using Bayesian model averaging. When these procedures are used, msBayes supports recent divergences without support for synchronous divergence in the Oaks et al. data and we further present a simulation analysis that demonstrates that msBayes can have high power to detect asynchronous divergence under narrower priors for divergence time. Our findings highlight the need for exploration of plausible parameter space and prior sampling efficiency for ABC samplers in high dimensions. We discus potential improvements to msBayes and conclude that when used appropriately with model averaging, msBayes remains an effective and powerful tool.