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The purpose of this paper is to show that a decontextualized approach to ethical issues is not just unhelpful for the decision making process of real, situated human beings, but dangerous. This is so, because by neglecting the context in which people make moral decisions we run the risk of reinforcing or furthering injustices against already disadvantaged groups. To show this, I evaluate three moral obligations that our ability to obtain genetic information has made salient: the duty to obtain genetic information about ourselves, the obligation to inform family members about genetic risks and the duty not to reproduce when we know that there is a high risk of transmitting a serious disease or defect. I will argue here that in ignoring the context in which these moral obligations are put into practice, and in particular the situation of women in our society, those who defend these moral duties might be furthering injustices against women.  相似文献   
3.
Viruses cause significant damage in agricultural crops worldwide. Disease management requires sensitive and specific tools for virus detection and identification. Also, detection techniques need to be rapid to keep pace with the continuous emergence of new viral diseases. The genus Fabavirus is composed of five viruses infecting many economically important crops worldwide. This research describes the development of a procedure based on flow‐through hybridisation (FTH), which is faster than and as sensitive as conventional hybridisation for virus detection in tissue‐prints from infected plants. Six digoxigenin‐labelled RNA probes were synthesised with two levels of specificity: (a) five specific for each viral species within this genus, and (b) a genus‐specific probe that hybridises with a nucleotide sequence signature only found in the 5′‐untranslated region of the genus Fabavirus, which is the first of this type reported for plant viruses. The new procedure developed is useful for rapid detection and discrimination of the five fabaviruses identified so far and opens the possibility of discovering new species of this genus.  相似文献   
4.
This article documents the addition of 111 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Acipenser oxyrinchus desotoi, Anopheles nuneztovari sensu lato, Asellus aquaticus, Calopteryx splendens, Calopteryx virgo, Centaurea aspera, Centaurea seridis, Chilina dombeyana, Proctoeces cf. lintoni and Pyrenophora teres f. teres.  相似文献   
5.
Tomato apex necrosis virus (ToANV, species Tomato marchitez virus, genus Torradovirus, family Secoviridae) causes a severe tomato disease in Mexico. One distinctive feature of torradoviruses compared with other members of the family Secoviridae is the presence of an additional open reading frame (ORF) in genomic RNA2 (denominated RNA2‐ORF1), located upstream of ORF2. RNA2‐ORF2 encodes a polyprotein that is processed into a putative movement protein and three capsid proteins (CPs). The RNA2‐ORF1 protein has homologues only amongst other torradoviruses and, so far, no function has been associated with it. We used recombinant and mutant ToANV clones to investigate the role of the RNA2‐ORF1 protein in various aspects of the virus infection cycle. The lack of a functional RNA2‐ORF1 resulted in an inability to systemically infect Nicotiana benthamiana and tomato plants, but both positive‐ and negative‐strand RNA1 and RNA2 accumulated locally in agroinfiltrated areas in N. benthamiana plants, indicating that the RNA2‐ORF1 mutants were replication competent. Furthermore, a mutant with a deletion in RNA2‐ORF1 was competent for virion formation and cell‐to‐cell movement in the cells immediately surrounding the initial infection site. However, immunological detection of the ToANV CPs in the agroinfiltrated areas showed that this mutant was not detected in the sieve elements even if the surrounding parenchymatic cells were ToANV positive, suggesting a role for the RNA2‐ORF1 protein in processes occurring prior to phloem uploading, including efficient spread in inoculated leaves.  相似文献   
6.
Mixed infections have been broadly applied to the study of bacterial pathogens in animals. However, the application of mixed infection-based methods in plant pathogens has been very limited. An important factor for this limitation is the different dynamics that mixed infections have been reported to show in the different types of models. Reports in systemic animal infections have shown that any bacterium has the same probability of multiplying within a mixed infection than in a single infection. However, in plant pathogens, bacterial growth in a mixed infection does not seem to reflect growth in a single infection, as growth interference takes place between the co-inoculated strains. Here we show that growth interference in mixed infection between different Pseudomonas syringae strains is not intrinsic to growth within a plant host, but dependent on the dose of inoculation. We also show that the minimal inoculation dose required to avoid interference depends on the aggressiveness of the pathogen as well as the type of virulence factor that differentiates the co-inoculated strains. This study establishes the basis for the use of mixed infection-based applications to the study of phytopathogenic bacteria. Analysis of the virulence of a type III effector mutant and an hrp regulatory mutant illustrate the increased accuracy and sensitivity of competitive index assays vs. regular growth assays. Several applications of this assay are addressed, and potential implications for this and other mixed infection-based methods are discussed.  相似文献   
7.
A morphological and anatomical study of fruits of 24 taxa ofLinaria Miller from south-west Spain has been made. Followingexamination of these species, by scanning electron and lightmicroscopy, five morphological types are established relatingto hair types, symmetry and dehiscence of capsules. A key tothe different species or groups of species is provided. Finally,dehiscence mechanisms are discussed briefly. Copyright 1999Annals of Botany Company Pericarp, hairs, dehiscence, SEM, Antirrhineae.  相似文献   
8.
Seeds of 24 taxa of Linaria from south-west Spain were examinedwith a scanning electron microscope and light microscope. Basedon seed features such as shape, surface ornamentation and cellshape, seven morphological types were recognized. Seeds of thedifferent types are described, illustrated and compared. A keyto distinguish the different species or groups of species isprovided. Copyright 1999 Annals of Botany Company Seed-coat, SEM, anatomy, Scrophulariaceae, Antirrhineae, Linaria .  相似文献   
9.
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.  相似文献   
10.
1. Shallow lake ecosystems are normally dominated by submerged and emergent plants. Biological stabilising mechanisms help preserve this dominance. The systems may switch to dominance by phytoplankton, however, with loss of submerged plants. This process usually takes place against a background of increasing nutrient loadings but also requires additional switch mechanisms, which damage the plants or interfere with their stabilising mechanisms. 2. The extent to which the details or even major features of this general model may change with geographical location are not clear. Manipulation of the fish community (biomanipulation) has often been used to clear the water of algae and restore the aquatic plants in northerly locations, but it is again not clear whether this is equally appropriate at lower latitudes. 3. Eleven parallel experiments (collectively the International Mesocosm Experiment, IME) were carried out in six lakes in Finland, Sweden, England, the Netherlands and Spain in 1998 and 1999 to investigate the between‐year and large‐scale spatial variation in relationships between nutrient loading and zooplanktivorous fish on submerged plant and plankton communities in shallow lakes. 4. Comparability of experiments in different locations was achieved to a high degree. Cross‐laboratory comparisons of chemical analyses revealed some systematic differences between laboratories. These are unlikely to lead to major misinterpretations. 5. Nutrient addition, overall, had its greatest effect on water chemistry then substantial effects on phytoplankton and zooplankton. Fish addition had its major effect on zooplankton and did not systematically change the water chemistry. There was no trend in the relative importance of fish effects with latitude, but nutrient addition affected more variables with decreasing latitude. 6. The relative importance of top‐down and bottom‐up influences on the plankton differed in different locations and between years at the same location. The outcome of the experiments in different years was more predictable with decreasing latitude and this was attributed to more variable weather at higher latitudes that created more variable starting conditions for the experiments.  相似文献   
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