1,722,110 research outputs found
Reactions of 2-bromopropanamides with conjugated bases of representative beta-dicarbonyl compounds. Synthesis of 2,5-dioxopyrrolidines and oxazolidine-4-ones
No full textReactions of 2-bromopropanamides with potassium enolates of representative beta dicarbonyl compounds provide, in
high yields, open and heterocyclic compounds through a C-C or C-O akylation reaction. Whereas C-alkylation products form
in all conditions tested under relevant diastereoselectivity, O-alkylation takes place only in the presence of silver promoters, and
shows partial diastereoselectivity
Commento all'art. 148
No full textIl commento all'art. 148 esamina la nuova disciplina relativa alla composizione del collegio sindacale (ed i conseguenti problemi applicativi) delle società quotate
The Determinants of the outsider director compensation: an empirical analisys of UK banks and non banks.
No full textThe Determinants of the Outside Director Compensation: an empirical analysis of UK banks and non-banks.
No full textPathological changes in human insulitis
No full textPurpose of review: Type 1 diabetes mellitus is a chronic disease resulting from autoimmune destruction of pancreatic β-cells in genetically predisposed individuals. The progressive loss of β-cells leads to insulin deficiency, which becomes almost invariably absolute a few years after diagnosis. The pathologic hallmark of such a disease is the mononuclear infiltration of pancreatic islets (insulitis), which has been well characterized in animal models and, to a much lesser extent in humans. Recurrent insulitis has also been shown to occur in transplanted pancreas in type 1 diabetic subjects. We here review the most recent articles that have provided novel important insights into the mechanisms involved in human islet inflammation and destruction during the immunopathogenic process leading to disease development and in recurrent autoimmunity and alloimmunity, which can result in pancreatic graft failure.
Recent findings: Recent findings suggest that enteroviral infection can indeed take place in human pancreatic β-cells; however, the direct contribution of such infections to islet inflammation and destruction remains to be elucidated. On the side of molecular mechanisms of immune-mediated β-cell damage, a major role of NF-kB activity has been demonstrated. In the area of transplantation, recurrent autoimmunity with islet inflammation can take place in transplanted pancreatic tissue; however this phenomenon rarely occurs when full immunosuppression is given.
Summary: Type 1 diabetes mellitus results from a chronic process of islet autoimmunity characterized by islet inflammation and destruction by several components of the immune system such as mononuclear cells, cytokine, chemokines, etc. On this background, environmental factors such as viral infections may contribute to disease development in a subset of genetically predisposed individuals
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
Fractional excitations in one-dimensional fermionic systems
No full textWe study the soliton modes carrying fractional quantum numbers in one-dimensional fermionic systems. In particular, we consider the solitons in the one-dimensional fermionic superfluids. For the s-wave order parameter with phase twisted by an angle φ, the complex Z 2 soliton may occur carrying a localized fractional quantum number φ/(2π). If the system is finite with length L, we show the existence of a uniform background -φ/(2πL) which, though vanishing in the thermodynamic limit, is essential to maintain the conservation of the total integer quantum number. This analysis is also applicable to other systems with fractional quantum numbers, thus providing a mechanism to understand the compatibility of the emergence of fractional quantum number in the thermodynamic limit of a finite system with only integer quantum numbers. For the p-wave pairing case, the Majorana zero mode may occur associated with a real Z 2 soliton, and the fractionalized quantum number is the dimension of the single particle Hilbert space, which turns out to be 1/2. Again for a finite system with length L, there is an accompanying uniform dimension density -1/(2L) to maintain the dimension of the Hilbert space invariant. We conjecture a connection of the dimension density of one-dimensional solitons with the quantum dimension of topological excitations
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