86,562 research outputs found
Le lumie di Sicilia: note storiche e botaniche
No full textCitrus lumia Risso is one of the old cultivated limes in Sicily, Mediterranean Europe and North Africa; For this reason, besides lumia, it is called Mediterranean lime. It is a small tree, with unarmed branches; obovate, obtuse leaves, with serrate margins and slightly winged petioles; flowers of medium size, fragrant, with petals externally reddish; fruit globose, umbonate, with base and apex de- pressed; umbo conical, dotted at the base; smooth, yellow-sulphureous, aromatic peel; thin and bitter mesocarp; endocarp with sweet juice, consisting of 9 -11 logs containing many seeds. It is distinguished from C. limetta Risso by the colour of petals and some other carpological and foliar characters, but mainly for non-acid juice. The two limes were already described in the masterly citrus work of FeRRaRiuS (1646), where in a table these are shown together as Lima dulcis et Lima acris. Cultivation of “lumia”, was once intended for the production of fruits used in the essence and food industry, nowadays is amateur, which is why this citrus has been preserved. In addition to the botanical characteristics of C. lumia, the identity of the “lumia” and its history are also discussed with respect to its cultivation in Sicily, as well as to the correspondence of this citrus with the “sweet lime” by the English authors
Le lumie di Sicilia: note storiche e botaniche
No full textCitrus lumia Risso is one of the old cultivated limes in Sicily, Mediterranean Europe and North Africa; For this reason, besides lumia, it is called Mediterranean lime. It is a small tree, with unarmed branches; obovate, obtuse leaves, with serrate margins and slightly winged petioles; flowers of medium size, fragrant, with petals externally reddish; fruit globose, umbonate, with base and apex depressed; umbo conical, dotted at the base; smooth, yellow-sulphureous, aromatic peel; thin and bitter mesocarp; endocarp with sweet juice, consisting of 9 -11 logs containing many seeds. It is distinguished from C. limetta Risso by the colour of petals and some other carpological and foliar characters, but mainly for non-acid juice. The two limes were already described in the masterly citrus work of Ferr arius (1646), where in a table these are shown together as Lima dulcis et Lima acris. Cultivation of “lumia”, was once intended for the production of fruits used in the essence and food industry, nowadays is amateur, which is why this citrus has been preserved. In addition to the botanical characteristics of C. lumia, the identity of the “lumia” and its history are also discussed with respect to its cultivation in Sicily, as well as to the correspondence of this citrus with the “sweet lime” by the English authors
On semidefinite lift-and-project of combinatorial optimization problems
No full textFinding the stability and the chromatic number of a graph are two among the fundamental problems in combinatorial optimization. Given a graph, the first calls for a stable set of maximum cardinality, i.e. a subset of vertices such that no two are adjacent; the latter asks for a partition of the nodes into the minimum number of stable sets (i.e. colors).
Both the stable set and graph coloring problems are well-known to be NP-hard, hence no
polynomial time algorithm to solve them exactly is expected to exists unless P=NP. Thus, the study of strong relaxations of these two problems is a well-researched topic. In particular, the Lov\'asz theta function provides at the same time a good upper bound on the stability number of a graph and a lower bound on the chromatic number of its complement. It can be computed in polynomial time by solving a semidefinite program, which in addition turns often out to be fairly tractable in practice. As a consequence, achieves a hard-to-beat trade-off between computational effort and strength of the bound. Hierarchies of relaxations to strengthen both towards the stability and chromatic number have been documented, but in general such improvements come at a heavy computational burden with off-the-shelf SDP algorithms and require highly specialized methods to be addressed.
In the last decades, Lift-and-Project methods have gained a lot of attention, being able to generate strong relaxations for combinatorial optimization problems. In particular, starting from any linear relaxation \lov\ and \sch's Lift-and-Project framework generates a semidefinite relaxation. Its application to the fractional stable set polytope showed its potential, producing bounds stronger than but in general they come at a nontrivial computational cost.
In this thesis we introduce a new semidefinite relaxation for the stable set problem obtained by the lifting of a more compact linear formulation than the classical one. Then, we characterize some classes of valid inequalities for the stable set polytope which are implied by our proposal. We then discuss how to face the computational burden arising from these semidefinite programs by the employment of a general purpose solver for SDPs.
Despite Lift-and-Project applications have been widely studied on the Stable Set problem, to the best of our knowledge none on the Graph Coloring problem have been presented. We investigate its employment in this problem, showing that the resulting SDP can yield bounds above the fractional chromatic number, a remarkable threshold not so straightforward to cross with semidefinite programming.
Although interior-point methods achieve good accuracy in reasonable time for small and medium size SDPs, their scalability to large instances is often compromised by memory requirements.
On the other hand, Alternating Direction Methods of Multipliers currently represent the most popular first-order alternatives, being suited to scale to much larger semidefinite programs. This of course at some cost in accuracy, that should be correctly addressed when bounding the optimal solution of some combinatorial optimization problem. In this work we focus on an ADMM designed for SDPs in standard form and extend it to deal with inequalities. Moreover, we report different methods to compute a valid bound on the optimal value of the SDP starting from a medium accuracy solution and we discuss the employments of these methodologies within ADMMs
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Pharmacognostic approach to evaluate the micromorphological, phytochemical and biological features of Citrus lumia seeds
No full textThis study evaluated the micro-morphology as well as the chemical and biological features of Citrus lumia seeds. The cream-colored pyriform seed showed a woody coat covered by a thick layer of mucilage and an embryo with two large cotyledons rich in oil bodies. Hydroxycinnamic acid glycosides and flavonoids are the most abundant compounds in methanol and ethyl acetate extracts (ME and EAE), respectively. Conversely, fatty acids and α-tocopherol represent the main bioactive compounds in the hexane extract (HE). ME showed the most promising antioxidant and anti-inflammatory activities already in cell-free assays. These results were confirmed by experiments carried out on human primary cells. Indeed, ME showed the best inhibitory activity against heat-induced haemolysis and ROS formation in erythrocytes. Moreover, the same order of potency (ME > EAE > HE) was observed also on peripheral blood mononuclear cells, in which the seed extracts were able to decrease TNF-α and IL-6 release after LPS-induced inflammation
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
Also By The Same Author: AKTiveAuthor, a Citation Graph Approach to Name Disambiguation
No full textThe desire for definitive data and the semantic web drive for inference over heterogeneous data sources requires co-reference resolution to be performed on those data. In particular, name disambiguation is required to allow accurate publication lists, citation counts and impact measures to be determined. This paper describes a graph-based approach to author disambiguation on large-scale citation networks. Using self-citation, co-authorship and document source analyses, AKTiveAuthor clusters papers, achieving precision of 0.997 and recall of 0.818 over a test group of eight surname clusters
John F. Kennedy telegram to Roosevelt
No full textJersey Homesteads (later the Borough of Roosevelt) was established in the 1930s as an agro-industrial cooperative community. It was established specifically for urban Jewish garment workers, many of whom had emigrated from Europe. President John F. Kennedy sent a telegram to the citizens of Roosevelt, New Jersey, apologizing for not being able to attend the memorial dedication in honor of former President Franklin Delano Roosevelt. (Jersey Homesteads became Roosevelt in 1945 in honor of the president.) President Kennedy expressed his gratitude to the people of Roosevelt for constructing the memorial, and commented that it will serve as a constant reminder of Roosevelt's good works
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