Search results for "extension"
showing 10 items of 534 documents
Quasivarieties of Algebras
2001
This chapter plays a twofold role in the book. Firstly, the chapter surveys basic facts about quasivarieties of algebras. These facts are widely utilised in the subsequent chapters devoted to algebraizable logics. Secondly, the chapter shows how the methods initially elaborated for protoalgebraic sentential logics in the first part can be also applied in the area of equational logic. Most of the results presented in this chapter are proved by way of adapting the purely consequential methods of sentential logic to the needs of the (quasi) equational systems associated with quasivarieties of algebras.
Chromatin modifiers and recombination factors promote a telomere fold-back structure, that is lost during replicative senescence.
2020
Telomeres have the ability to adopt a lariat conformation and hence, engage in long and short distance intra-chromosome interactions. Budding yeast telomeres were proposed to fold back into subtelomeric regions, but a robust assay to quantitatively characterize this structure has been lacking. Therefore, it is not well understood how the interactions between telomeres and non-telomeric regions are established and regulated. We employ a telomere chromosome conformation capture (Telo-3C) approach to directly analyze telomere folding and its maintenance in S. cerevisiae. We identify the histone modifiers Sir2, Sin3 and Set2 as critical regulators for telomere folding, which suggests that a dis…
DECORIN EFFECTS ON PROTEOMIC PROFILING OF BREAST CANCER CELLS: AN UPDATED STUDY
2015
The malignant carcinomas are characterized by several capabilities acquired by the neoplastic cells, among which the ability to invade the extracellular matrix (ECM) and to establish a crosstalk with several ECM components. Under this respect, the extracellular microenvironment is an entity extraordinarily rich of information with opposite signals. Our group has long undertaken the study of the effects of ECM molecules on the behavior of cancer cells in vitro. Among the studied molecules, the decorin was found to exert a non-permissive effect on the growth and motility of the transfected tumor cells. The decorin, belongs to the family of small leucine-rich proteoglycans (SLRP) and is involv…
Extranodal extension in N1-adenocarcinoma of the pancreas and papilla of Vater: A systematic review and meta-analysis of its prognostic significance
2016
The aim of the study was to investigate the prognostic role of extranodal extension (ENE) of lymph node metastasis in adenocarcinoma of the pancreas (PDAC) and papilla [cancer of the papilla of Vater (CPV)]. A PubMed and SCOPUS search from database inception until 5 January 2015 without language restrictions was conducted. Eligible were prospective studies reporting data on prognostic parameters in individuals with PDAC and/or CPV, comparing participants with the presence of ENE (ENE +) with those with intranodal extension (ENE). Data were summarized using risk ratios for number of deaths/recurrences and hazard ratios for time-dependent risk related to ENE+, adjusted for potential confounde…
Modeling the effect of ethanol vapor on the germination time of Penicillium chrysogenum.
2005
The influence of ethanol vapor on germination of Penicillium chrysogenum was determined on yeast nitrogen base plus glucose agar medium at 25 degrees C. Ethanol vapors were generated by 0 to 6% (wt/wt) ethanol solutions at the bottom of hermetically closed petri dishes. The logistic equation was used to describe the data as the percentage of germination versus time and to estimate the germination time. The effect of ethanol concentration on germination time was described by a new reparameterized equation, resulting in an estimated limiting ethanol concentration of 4.3%. Up to 3% ethanol, all spores germinated, and the germination time increased with increasing ethanol concentration. At 3.5 …
Extension theory and the calculus of butterflies
2016
Abstract This paper provides a unified treatment of two distinct viewpoints concerning the classification of group extensions: the first uses weak monoidal functors, the second classifies extensions by means of suitable H 2 -actions. We develop our theory formally, by making explicit a connection between (non-abelian) G-torsors and fibrations. Then we apply our general framework to the classification of extensions in a semi-abelian context, by means of butterflies [1] between internal crossed modules. As a main result, we get an internal version of Dedecker's theorem on the classification of extensions of a group by a crossed module. In the semi-abelian context, Bourn's intrinsic Schreier–M…
Bone mineral density and physical activity in 50–60-year-old women
1991
Abstract The bone mineral density (BMD) of the calcaneus was measured utilizing a single energy photon absorption method in 108 women, aged 50–60 years. The women who participated in vigorous exercise two or more times a week or whose total physical activity amounted to 4 h a week had significantly higher BMD values than those who exercised less than two times a week or did less than 4 h physical activity a week. The physically active women also showed higher values for leg extension force and maximal oxygen uptake. BMD and leg extension force were positively correlated, whereas correlations between BMD and body mass, and the width of the calcaneus were negative. When other life-style varia…
Branch-and-Price-and-Cut for the Truck-and-Trailer Routing Problem with Time Windows
2018
In this paper, we present a new branch-and-price-and-cut algorithm to solve the truck-and-trailer routing problem with time windows (TTRPTW) and two real-world extensions. In all TTRPTW variants, the fleet consists of one or more trucks that may attach a trailer. Some customers are not accessible with a truck-and-trailer combination, but can however be serviced by one if the trailer is previously detached and parked at a suitable location. In the first extension, the planning horizon comprises two days and customers may be visited either on both days or only once, in which case twice the daily supply must be collected. The second extension incorporates load transfer times depending on the …
A facies distribution model controlled by a tectonically inherited sea bottom topography in the carbonate rimmed shelf of the Upper Tithonian–Valangi…
2016
The Upper Tithonian–Valanginian shallow-water carbonates outcropping in the Palermo Mts (NW Sicily) consist of several facies associations reflecting different depositional environments of a carbonate rimmed shelf, pertaining to the Southern Tethyan continental margin. The reconstructed depositional model, based on the sedimentological features, cyclic facies arrangement and biota distribution, shows that a wide protected lagoon, dominated by algae, molluscs and scattered patch reefs, was bordered landward by a tidal flat, where stromatolitic algal mats were cyclically subaerial exposed, and seaward by a marine sand belt and reef complex. Oolitic packstone-grainstone lithofacies, cyclically…
Splines Computation by Subdivision
2015
In this chapter, fast stable algorithms are presented, which compute splines’ values at dyadic and triadic rational points starting from their samples at integer grid points. The algorithms are implemented by the causal-anticausal recursive filtering of initial data samples, which is followed by iterated application of FIR filters. Extension of the algorithms to the multidimensional case is straightforward. A natural application of the presented subdivision algorithms is for upsampling of signals and images. A few upsampling examples are provided.