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REPRESENTATION THEOREMS IN A 4-DIMENSIONAL EUCLIDEAN SPACE. A NEW CASE
No full textIn a 4-dimensional Euclidean space, representation theorems have been recently obtained for isotropic functions depending on an arbitrary number of scalars, skew-symmetric second order tensors and symmetric second order tensors; at least one of these last ones is assumed to have an eigenvalue with multiplicity 1. The case with at least a non null vector, among the independent variables, has already been treated in literature. Here the new case is considered where no symmetric tensor has eigenvalues with multiplicity 1, but there is at least one symmetric tensor with two distinct eigenvalues.
The result is a finite, but long, set of scalar valued isotropic functions such that every other scalar function of the same variables can be expressed as a function of the elements of this set.
Similarly, a set of symmetric tensor valued isotropic functions is found such that every other symmetric tensor valued function of the same variables can be expressed as a linear combination, trough scalar coefficients, of the elements of this set. Finally, we obtain also a set of skew-symmetric tensor valued isotropic functions such that every other skew-symmetric tensor valued function of the same variables can be expressed as a linear combination, through scalar coefficients, of the elements of this set
Some Useful Tensorial Identies for Extended Thermodynamics
No full textThe balance equations for Extended Thermodynamics with an arbitrary number of moments is
here considered and a particular method is followed to obtain from them a finite number
of equations; this method is based on the suggestions coming from the non relativistic
limit of the corresponding relativistic model. The closure of this reduced set of
equations is obtained by imposing the entropy principle and the Galilean relativity
principle. To this end some tensorial properties are necessary and have already used in
literature without proving them. This gap is here filled, by proving them also in the
general case of the above mentioned closure method. Also other interesting consequences
are outlined
Representation Theorems for skew-symmetric tensorial functions in a 4-dimensional Euclidean space
No full textREPRESENTATION THEOREMS IN A 4-DIMENSIONAL EUCLIDEAN SPACE. THE CASE WITH ONLY SKEW-SYMMETRIC TENSORS
No full textIn a 4-dimensional Euclidean space, representation theorems have been recently obtained for isotropic
functions depending on an arbitrary number of scalars, skew-symmetric second order tensors and symmetric
second order tensors; the cases has been treated where at least one of these last ones has an eigenvalue with
multiplicity 1 or two distinct eigenvalues with multiplicity 2. The case with at least a non null vector,
among the independent variables, was already treated in literature. There remain the case where every
symmetric tensor has an eigenvalue with multiplicity 4; but, in this case, it plays a role only through its
trace. Consequently, it remains the case where the independent variables, besides scalars, are skew-symmetric
tensors. This case is treated in the present paper. As in the other cases, the result is a finite set of scalar valued isotropic functions such that every other scalar function of the same variables can be expressed as a function of the elements of this set.
Similarly, a set of tensor valued isotropic functions is found such that every other tensor valued function
of the same variables can be expressed as a linear combination, trough scalar coefficients, of the elements
of this set. This result is achieved both for symmetric functions , and for skew-symmetric functions
Proximate composition of edible sea urchin Paracentrotus lividus roe commercialised in Sardinia
No full textChemical analyses on edible sea urchin Paracentrotus lividus (Echinoidea) gonads legally (L) and illegally (I) sold in Sardinia (Italy) were carried out during the fishing season 2008-2009. Statistical tests performed on moisture, ash, crude protein, lipid and carbohydrate content detected significant differences between L and I samples, but also among roe illicitly commercialised (I) by ambulant vendors in different Sardinian coastal districts
Proximate composition of edible sea urchinParacentrotus lividusroe commercialised in Sardinia = Composizione centesimale di gonadi del riccio di mare eduleParacentrotus lividuscommercializzate in Sardegna
Full text linkChemical analyses on edible sea urchinParacentrotus lividus(Echinoidea) gonads legally (L) and illegally (I) sold in Sardinia (Italy) were carried out during the fishing season 2008-2009. Statistical tests performed on moisture, ash, crude protein, lipid and carbohydrate content detected significant differences between L and I samples, but also among roe illicitly commercialised (I) by
ambulant vendors in different Sardinian coastal districts
Repopulation by endogenous hepatocytes does not reconstitute liver mass in rats treated with retrorsine
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Liver repopulation and carcinogenesis: two sides of the same coin?
No full textLiver repopulation by transplanted normal hepatocytes has been described in a number of experimental settings. Extensive repopulation can also occur from the selective proliferation of endogenous normal hepatocytes, both in experimental animals and in the human liver. This review highlights the intriguing association between clinical and experimental conditions related to liver repopulation and an increased risk for development of hepatocellular carcinoma. It is suggested that any microenvironment that is able to sustain the clonal growth of normal transplanted (or endogenous) hepatocytes is also geared to select for the emergence of rare resistant cells with an altered phenotype. Whereas the first pathway leads to liver repopulation with normal histology, the latter results in the growth of focal proliferative lesions and carries an increased risk of neoplastic disease. The implications of this association are discussed, both in terms of pathogenetic significance and possible therapeutic exploitation
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