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101.
Three muscles ( Semimembranosus, Quadriceps femoris, Adductor ) from Podolian young bulls (aged 18 months) were processed into bresaolas, which were compared with commercial products, in terms of sensory profile and preference expressed by consumers. Slope analysis was conducted to study the preference drivers. The preference of homogeneous groups of consumers and the relationships with sensory properties of bresaola were investigated using partial least squares (PLS) regression analysis. The products differed for several sensory properties, such as sweetness, flavor intensity ( P <  0.001), saltiness ( P <  0.01), peppered, seasoned and tenderness ( P <  0.05). The slope analysis showed that taste/flavor ( k =  0.86) and appearance ( k =  0.76) play an important role in orienting consumer preference, while texture ( k =  0.54) is less important. No general trend was found for product liking. Conversely, PLS regression clustered the consumers in homogeneous groups: one preferred the commercial products characterized by sensory properties such as peppered, saltiness, seasoned and marbling, another one was more oriented toward properties such as sweetness, odor and chewiness, which characterized Podolian bresaolas.

PRACTICAL APPLICATION


Partial least squares regression analysis clustered the consumers in homogeneous groups according to their liking: those preferring peppered, salty, seasoned and marbling bresaolas versus those oriented toward sweet and odorous products. In addition, the relationship between overall liking and attribute liking (appearance, taste/flavor and texture) was analyzed by linear regression analysis. This may be helpful in order to establish meaningful criteria for grading bresaolas and identify the particular attributes that move its acceptance (i.e., taste/flavor and appearance rather than texture).  相似文献   
102.
The mechanisms that determine population structure in highly mobile marine species are poorly understood, but useful towards understanding the evolution of diversity, and essential for effective conservation and management. In this study, we compare putative sperm whale populations located in the Gulf of Mexico, western North Atlantic, Mediterranean Sea and North Sea using mtDNA control region sequence data and 16 polymorphic microsatellite loci. The Gulf of Mexico, western North Atlantic and North Sea populations each possessed similar low levels of haplotype and nucleotide diversity at the mtDNA locus, while the Mediterranean Sea population showed no detectable mtDNA diversity. Mitochondrial DNA results showed significant differentiation between all populations, while microsatellites showed significant differentiation only for comparisons with the Mediterranean Sea, and at a much lower level than seen for mtDNA. Samples from either side of the North Atlantic in coastal waters showed no differentiation for mtDNA, while North Atlantic samples from just outside the Gulf of Mexico (the western North Atlantic sample) were highly differentiated from samples within the Gulf at this locus. Our analyses indicate a previously unknown fidelity of females to coastal basins either side of the North Atlantic, and suggest the movement of males among these populations for breeding.  相似文献   
103.
The Late Miocene and Pliocene continental sediments in the Granada Basin (southern Spain) have yielded large amounts of fossil small mammals in 37 localities from 11 sections. The aim of this paper is to integrate faunistic, stratigraphic, and sedimentary criteria to unravel the geological history of the continental infilling of the basin. The palaeontological study has led to a detailed biozonation on the basis of rodents, which helps to correlate in detail the different sedimentary units found in the basin, and to follow the changes of the different sedimentary systems and their palaeogeographical evolution through time. Combination of the proposed biostratigraphy and the reinterpretation of the magnetostratigraphic analyses of the Barranco del Purcal section allows us to assign an absolute age slightly older than 5.23 Ma to the Turolian–Ruscinian boundary (MN13‐MN14).  相似文献   
104.
Analysis of zymograms of extracts of Trypanosoma cruzi isolated from different hosts in Argentina allowed characterization of 12 zymodemes or "isozymic strains," only six of which were found in human patients. Two of these six zymodemes (Z1 and Z12) were widely distributed and found in more than 80% of human patients. These two "major natural clones" differed significantly in pathogenic activity. Because the groupings obtained by studying enzymes and kinetoplast DNA (kDNA) were similar, it is possible to identify the zymodeme by analyzing kDNA. A 290-bp fragment was amplified by PCR using primers for the sequences flanking the hypervariable regions of kDNA minicircles. Labeled probes for this fragment, prepared from Z1 and Z12 reference stocks, hybridized specifically with PCR-amplified kDNA from parasite stocks, allowing identification of zymodemes.  相似文献   
105.
106.
The ultrastructure of testa seed in the genus Neotinea (Orchidaceae, Orchidinae) was examined for the first time. The morphology of the seed and of the anticlinal and periclinal walls was analysed by scanning electron microscopy. Quantitative data concerning the length and width of the seed and embryo, seed and embryo volume, free air space, and number of cells along the longitudinal axis are presented. In all species, the seeds are fusiform in shape with transverse ridges on the inner periclinal walls. This ornamentation pattern is characteristic for the genus Neotinea . It is a good diagnostic value supporting the monophyly of this genus, which has recently been proposed by several authors.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 133–140.  相似文献   
107.
Changes in net CO2 assimilation rate (A) are often partitioned into contributions from changes in different variables using an approach that is based on an expression from calculus: namely the definition of the exact differential of A, which states that an infinitesimal change in A (dA) is equal to the sum of infinitesimal changes in each of the underlying variables, each multiplied by the partial derivative of A with respect to the variable. Finite changes in A can thus be partitioned by integrating this sum across a finite interval. The most widely used method of estimating that integral is a coarse discrete approximation that uses partial derivatives of the natural logarithm of A rather than A itself. This yields biased and ambiguous estimates of partitioned changes in A. We present an alternative partitioning approach based on direct numerical integration of dA. The new approach does not require any partial derivatives to be computed, and it can be applied under any conditions to estimate the contributions from changes in any photosynthetic variable. We demonstrate this approach using field measurements of both seasonal and diurnal changes in assimilation rate, and we provide a spreadsheet implementing the new approach.  相似文献   
108.
The melanogenic marine bacterium Marinomonas mediterranea contains a multipotent polyphenol oxidase (PPO) able to oxidize substrates characteristic for tyrosinase and laccase. Thus, this enzyme shows tyrosine hydroxylase activity and it catalyzes the oxidation of a wide variety of o-diphenol as well as o-methoxy-activated phenols. The study of its sensitivity to different inhibitors also revealed intermediate features between laccase and tyrosinase. It is similar to tyrosinases in its sensitivity to tropolone, but it resembles laccases in its resistance to cinnamic acid and phenylthiourea, and in its sensitivity to fluoride anion. This enzyme is mostly membrane-bound and can be solubilized either by non-ionic detergent or lipase treatments of the membrane. The expression of this enzymatic activity is growth-phase regulated, reaching a maximum in the stationary phase of bacterial growth, but l -tyrosine, Cu(II) ions, or 2,5-xylidine do not induce it. This enzyme can be separated from a second PPO form by gel permeation chromatography. The second PPO is located in the soluble fraction and shows a sodium dodecyl sulfate (SDS)-activated action on the characteristic substrates for tyrosinase, l -tyrosine, and l -dopa, but it does not show activity towards laccase-specific substrates. The involvement of the multipotent PPO in melanogenesis and its relationship with the SDS-activated form and with the alternative functions proposed for multicopper oxidases in other microorganisms are discussed.  相似文献   
109.
110.
Marine invertebrates show a high diversity of embryonic developmental modes and reproductive behaviour. However, little is known about the factors that are promoting the evolution of different strategies. The gastropod Crepidula coquimbensis has a direct embryonic development with encapsulated embryos showing a cannibalistic behaviour. Preliminary observations suggest that victim embryos are not randomly chosen. With intracapsular multipaternity, the intensity of cannibalism might vary according to the relatedness of the siblings. Paternity analyses based on highly polymorphic markers can provide valuable insights into this cannibalism behaviour. Ten polymorphic microsatellite loci were thus developed: the level of polymorphism is large enough to perform paternity analysis and investigate relatedness in this species.  相似文献   
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