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In a recent article, Joel Marks presents the amoralist argument against vivisection, or animal laboratory experimentation. He argues that ethical theories that seek to uncover some universal morality are in fact useless and unnecessary for ethical deliberations meant to determine what constitutes an appropriate action in a specific circumstance. I agree with Marks’ conclusion. I too believe that vivisection is indefensible, both from a scientific and philosophical perspective. I also believe that we should become vegan (unfortunately, like the two philosophers mentioned by Marks, I too am still struggling to reduce my meat and dairy consumption). However, I am in the dark as to Marks’ vision of normative deliberations in the spirit of amoralism and desirism.  相似文献   

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We are responding to a Letter to the Editor addressing the Method section of our paper “Different measures of ‘genome-wide’ DNA methylation exhibit unique properties in placental and somatic tissues.” The letter raised concerns that the protocol for Epigentek’s MethylFlash kit was followed incorrectly based on the wording of an online publication of our article. We admittedly made an error in the language used to describe the MethylFlash protocol in our initial submission and thus this was corrected as soon as it was brought to our attention. However, the error was only in language and not procedure. We are confident that the protocol was followed as stated in the insert provided with the MethylFlashTM Methylated DNA Quantification kit (Colorimetric).We are responding to a Letter to the Editor addressing the Method section of our paper “Different measures of ‘genome-wide’ DNA methylation exhibit unique properties in placental and somatic tissues” (Price ME, Cotton AM, PeÒaherrera MS, McFadden DE, Kobor MS, Robinson WP. Different measures of “genome-wide” DNA methylation exhibit unique properties in placental and somatic tissues. Epigenetics 2012; 7: 652–63; PMID: 22531475; 10.4161/epi.20221). The letter raised concerns that the protocol for Epigentek’s MethylFlash kit was followed incorrectly based on the wording of an online publication of our article. We admittedly made an error in the language used to describe the MethylFlash protocol in our initial submission and thus this was corrected as soon as it was brought to our attention. However, the error was only in language and not procedure. We are confident that the protocol was followed as stated in the insert provided with the MethylFlashTM Methylated DNA Quantification kit (Colorimetric).  相似文献   

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This article is a response to Klütsch and Crapon de Caprona  相似文献   

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BACKGROUND AND AIMS: Bilabiate flowers have evolved in many lineages of the angiosperms, thus representing a convincing example of parallel evolution. Similar to keel blossoms, they have obviously evolved in order to protect pollen against pollen-collecting bees. Although many examples are known, a comprehensive survey on floral diversity and functional constraints of bilabiate flowers is lacking. Here, the concept is widened and described as a general pattern. METHODS: The present paper is a conceptional review including personal observations of the authors. To form a survey on the diversity of bilabiate blossoms, a search was made for examples across the angiosperms and these were combined with personal observations collected during the last 25 years, coupled with knowledge from the literature. New functional terms are introduced that are independent of morphological and taxonomic associations. KEY RESULTS: Bilabiate constructions occur in at least 38 angiosperm families. They are characterized by dorsiventral organization and dorsal pollen transfer. They are most often realised on the level of a single flower, but may also be present in an inflorescence or as part of a so-called 'walk-around flower'. Interestingly, in functional terms all nototribic blossoms represent bilabiate constructions. The great majority of specialized bee-flowers can thus be included under bilabiate and keel blossoms. The syndrome introduced here, however, also paves the way for the inclusion of larger animals such as birds and bats. The most important evolutionary trends appear to be in the saving of pollen and the precision of its transfer. With special reference to the Lamiales, selected examples of bilabiate flowers are presented and their functional significance is discussed. CONCLUSIONS: Bilabiate blossoms protect their pollen against pollen-collecting bees and at the same time render their pollination more precisely. The huge diversity of realised forms indicate the high selection pressure towards the bilabiate syndrome. As bees are very inventive, however, bilabiate constructions will not represent the ultimate response to bees.  相似文献   

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Arthur G. Tansley never accepted Frederic E. Clements’ view that succession is a developmental process whose final stage, the climax formation, is determined primarily by regional climate and that all other types of vegetation are some kind of successional stage or arrested successional stage. Tansley was convinced that in a given region a variety of environmental factors could produce different kinds of climax formations. At the heart of their dispute was Clements’ organicist view of succession, i.e., the formation was a complex organism with an ontogeny and phylogeny. As early as 1905, Tansley offered an alternative to Clements’ complex organism, the quasi-organism, but Clements in private and public rejected this compromise. Tansley and other plant ecologists continued to criticize Clements’ theories for the next 20 years, but with no impact on Clements. John Phillips, a South African plant ecologist who was a follower of Clements, published a series of papers in 1934 and 1935 defending Clementsian ecology. These papers were triggered by the publication of a letter by another ecologist working in Africa who claimed that there was a strong correlation between soils and various kinds of climax vegetation, which was contrary to what was predicted by Phillips and Clements. In 1935, Tansley published an attack on Phillips and Clements and their developmental theory of succession. In it, he proposed the concept of the ecosystem as a way to get around Clements’ monoclimax theory by making the physical environment (e.g., soil chemistry, soil texture, soil moisture) as important a factor as climate, plants and other organisms in determining the composition and characteristics of ecological entities, i.e., ecosystems. Tansley’s ecosystem concept quickly replaced Clements’ monoclimax theory as a dominant paradigm in ecology.  相似文献   

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The effects of CO2 concentration on the morphological and anatomical characters of soybean (Glycine max) leaf were investigated by means of light microscopy and SEM. It was noticed that exomorphology did not show dramatic change, while stomatal density decreased with increasing CO2 concentration. Under SEM, no epicuticular wax was observed on both abaxial and adaxial sides of the control group as well as on adaxial side of the treatment group. However, leaf surface of abaxial side was noticed to be densely covered with microasterisk epicuticular wax when they were exposed to CO2-enriched environment. The epicuticular wax deposition was present in equal abundance on both stomatal and nonstomatal areas. Furthermore, leaf thickness increased significantly due largely to the origin of an extra layer of palisade in the treatment group. The results confirmed that CO2 enrichment might enhance cell division and induce greater quantity of epicuticular wax.  相似文献   

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Microbial safety of food products is often accomplished by the formulation of food-grade preservatives into the product. Because of the growing consumer demand for natural substances (including preservatives) in the composition of consumed foods, there is also a growing interest in the natural antimicrobial nisin, which has generally recognized as safe (GRAS) status for certain applications. During the products storage time, concentrations of preservative(s) are decreasing, which may eventually cause a serious problem in the food’s microbial safety. Here, for the first time we report on the non-linear response of a foodborne pathogen, Listeria monocytogenes, to sub-lethal concentrations of nisin.  相似文献   

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