2,513 research outputs found
Literatura y vida : Un perdido y El niño que enloqueció de amor
No full textFil: Vázquez Bigi, A. M. .
Northern Illinois Universit
Sediment yield for erosion evaluation in a small Apennine watershed, and location of sediment sources through the use of the USLE model and of air photo interpretation.
No full textSediment yield for erosion evaluation in a small Apennine watershed, and location of sediment sources through the use of the USLE model and of air photo interpretation.
D. Pavanelli, A. Bigi, M. Rigotti
Corresponding Author: D. Pavanelli, Dipartimento di Economia ed Ingegneria Agrarie, Università di Bologna, V.le G. Fanin 50, 40127 Bologna, Italy. Tel:+39 051 2096168, Fax:+39 051 2096171, E-mail: [email protected]
Soil erosion in the Apennines is quite a relevant issue, being a cause of land degradation and reducing the land available to farming. Mountain areas abandonment worsened landscape situation, because of the lack of erosion direct and indirect control.
Estimates of soil erosion activity in a mountain basin are usually made with a significant degree of uncertainty, because usually few data are available to calibrate erosion models or to directly estimate eroded soil amount, thus leading to inability of taking decision in conservation policies.
In order to evaluate the suspended sediment yield (SSY) carried by the Gaiana torrent, a ~9 km2 basin in the Bologna Apennines, we applied a very simple linear model previously built on a geomorphologically similar watershed nearby, which has a very large SSY dataset. This model estimates average SSY from the maximum rainfall intensity on a storm event basis: the simplicity of the model allowed its application on scarcely gauged basins, where precipitation is the main erosive agent, giving reasonable estimates of soil loss.
According to the philosophy behind this approach, we applied the USLE model to the Gaiana catchment, in order to have a further estimate of the order of magnitude of the sediment yield and to test our methodology. We also realized a chart of geomorphology and soil erosion by air photo interpretation, in order to be able to locate the source areas of sediment production. Furthermore, a river monitoring station along with a water samples has been installed at the Gaiana basin outlet. The few collected data since December 2004 have been employed to further verify the linear model efficiency. GIS analysis has been fundamental for extracting USLE factor from the digital elevation model of the basin, and to analyse vegetation cover and geomorphology of the Gaiana basin, as well as for air photo elaboration
Corrigendum to “Macroalgae to nanoparticles: Study of Ulva lactuca L. role in biosynthesis of gold and silver nanoparticles and of their cytotoxicity on colon cancer cell lines” [Mater. Sci. Eng. C 97 (2019) 498–509](S0928493118326729)(10.1016/j.msec.2018.12.066)
No full textThe authors regret having to add the ‘e’ letter to Franca Bigi. The authors would like to apologise for any inconvenience caused
Ex elega[n]tissimis Fausti An//drelini amoru[m] libris quattu//or selecti versus : cu[m] nonnullis alioru[m] poetaru[m]// carminib[us] puero[rum] i[n]stitutio[n]i sane qua[m] idoneis
No full textIn FrakturMit Beig. von Hermann von dem Busche, Johann Murmellius, Luigi Bigi Pittorio, Panfilo Sassi und Baptista GK 4.766
Total free lipids from MDR strain of Mycobacterium tuberculosis “M” reduce T cell activation and CTL activity in healthy individuals
No full textIncreasing evidence highlights the role of cell wall components in the effectiveness of different Mycobacterium tuberculosis (Mtb) strains in modulating host immune response. We previously demonstrated that the outbreak multidrug-resistant strain M displays a distinctive lipid profile in its cell envelope compared to the closely related sporadic strain 410. Both strains markedly differ in their ability to induce fully functional CD8+ T cells because of low CD69 signaling and impaired CD4+ T cell help. In this study, we evaluated the impact of extractable lipids (LP) from M (LP-M) and 410 (LP-410) on the activation and functionality of T cells from healthy individuals. PBMCs were cultured alone or with Mtb in the presence or absence of LP-M, LP-410, or LP from CD1551 mutants in polymorphic genes between M and 410. Then, surface CD69 and intracytoplasmic IL-2 (after 3 days of culture), as well as surface CD107 expression (after 6 days of culture) were determined in T cells by flow cytometry. In contrast to LP-410, LP-M induced low expression of CD69 and IL-2 in CD4+/CD8+ cells and of CD107 in CD8+ cells. Besides, LP from Mtb strains mutated in Rv1861c and Rv3787c genes inhibited H37Rv-induced T cell response without causing cell death. Thus, our results suggest that LP-M likely through mutations in Rv1861 and Rv3787c, inhibits the activation and functionality of T cells from PPD+ healthy human donors and might partially contribute to the development of immune evasion mechanisms in the M strain.Instituto de BiotecnologíaFil: Bigi, María Mercedes. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Bigi, María Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Imperiale, Belen Rocio. Academia Nacional de Medicina. Instituto de Medicina Experimental (IMEX); ArgentinaFil: Imperiale, Belen Rocio. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Soria, Marcelo Abel. Universidad de Buenos Aires. Facultad de Agronomía; ArgentinaFil: López, Beatriz. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas “Dr. Carlos G. Malbrán”. Laboratorio de Micobacterias; ArgentinaFil: Bigi, Fabiana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Bigi, Fabiana. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: de la Barrera, Silvia Susana. Academia Nacional de Medicina. Instituto de Medicina Experimental (IMEX); Argentin
Uniqueness of KKT Multipliers in Multiobjective Optimization
No full textThe uniqueness of the KKT multipliers of a nonlinear program has been studied ina well-known paper by Kyparisis. In the first part of this note, we show that the characterization obtained in that paper does not provide a satisfactory result for the multiobjective case. Thus, we introduce a new regularity condition, which involves also the objective functions, and we show that it is necessary and sufficient in order to have unique KKT multipliers. Moreover, we use this condition to refine a second-order necessary optimality condition, which has been obtained in a recent paper
Second Order Optimality Conditions for Differentiable Multiobjective Problems
No full textA second order optimality condition for multiobjective optimization with a set constraint is developed; this condition is expressed as the impossibility of nonhomogeneous linear systems. When the constraint is given in terms of inequalities and equalities, it can be turned into a John type multipliers rule, using a nonhomogeneous Motzkin Theorem of the Alternative. Adding weak second order regularity assumptions, Karush, Kuhn-Tucker type conditions are therefore deduced
Structural setting of the Cicolano - M. Calvo area (Central Apennines, Italy)
No full textThe studied area, belonging to the Central Apennines, is comprises
between the M. Filone-M. Navegna ridge in the west, and the
M. Calvo-Colle dei Montanari ridge in the east. Four tectonic units,
characterized by different sedimentary successions and by different
structural setting can be recognized in the area. They form a complex
embricate fan thrust system and are, from the higher to the
lower one: Reatini unit, Navegna unit, Salto-Nuria-Calvo unit, La
Torretta unit.
The Reatini unit is made of the Umbria-Marchean sedimentary
succession, and is tectonically placed on the Navegna and the Salto-
Nuria-Calvo units, by a thrust plane developed along the Ancona-
Anzio Auct. tectonic line. Its internal structural setting is characterized
by a minor thrust plane that placed a syncline involving the
Jurassic deposits on the overturned Cretaceous-Paleogene succession.
A Mesozoic slope-to-basin and a Cenozoic carbonate ramp succession,
developed along the northwestern margin of the Lazio-
Abruzzi carbonate platform paleodomain constitutes the Navegna
unit, located in the south of the Reatini unit. It is overthrust onto
the Salto-Nuria-Calvo unit by a thrust plane which corresponds to
the Olevano-Antrodoco line. Several minor thrust planes associated
to narrow hangingwall anticlines verging eastward in the Navegna
unit have been recognized.
The Salto-Nuria-Calvo unit can be divided in three sector
belonging to the Lazio-Abruzzi carbonate platform paleodomain: the
sedimentary succession of the Salto sector is made up of Cretaceous
carbonate platform deposits, covered unconformably by a Miocene
succession of carbonate ramp environment, and by a thick Early
Messinian siliciclastic turbidites succession. The internal structural
setting comprises minor folds and thrust planes that constitute carbonate
ridges surrounded by siliciclastic deposits. On the eastern
side of Salto lake, small carbonate ridges sometimes associated to
back thrust planes occur.
The M. Nuria sector is made of a Mesocenozoic sedimentary
succession deposited in a carbonate platform environment, that passes
southeastward to carbonate margin deposits. The stratigraphic
organization shows a progressive sinking of this sector during Cretaceous-
Paleogene time. Miocene carbonate ramp and Early Messinian
siliciclastic turbiditic deposits cover unconformably the previous
ones.
This unit is organized in anticlines associated to thrust plane
trending NW-SE. Minor back thrust planes and splays with thin levels
of turbiditic sandstone cropping out in their footwall, can be
observed in the eastern sector of the area. M. Calvo sector, constituted
by a Mesozoic carbonate platform margin sedimentary succession,
is the more external part of the the Lazio-Abruzzi carbonate
platform paleodomain, and it overthrusts with a low angle thrust
plane onto the more external unit of La Torretta unit, that is, on its
turn, made of the Meso-Cenozoic pelagic succession. The M. Calvo
area is organized in several minor tectonic slides, while its footwall
(La Torretta unit) shows narrow synclines and anticlines with an
inclined to overturned setting.
Tear faults associated to the compressive structures, trending
SW-NE and E-W, are also recognized.
From the Late Pliocene on, an extensional tectonic phase occurs
in the studied area with the development of main normal faults and the reactivation of some ancient structures
D-gap functions and descent techniques for solving quilibrium problems
No full textA new algorithm for solving equilibrium problems with differentiable bifunctions is provided. The algorithm is based on descent directions of a suitable family of D-gap functions. Its convergence is proved under assumptions which do not guarantee the equivalence between the stationary points of the D-gap functions and the solutions of the equilibrium problem. Moreover, the algorithm does not require to set parameters according to thresholds which depend on regularity properties of the equilibrium bifunction. Finally, the results of preliminary numerical tests on Nash equilibrium problems with quadratic payoffs are reported
A close look at auxiliary problem principles for equilibria
No full textThe auxiliary problem principle allows solving a given equilibrium problem (EP) through an equivalent auxiliary problem with better properties. The paper investigates two families of auxiliary EPs: the classical auxiliary problems, in which a regularizing term is added to the equilibrium bifunction, and the regularized Minty EPs. The conditions that ensure the equivalence of a given EP with each of these auxiliary problems are investigated. This analysis leads to extending some known results for variational inequalities and linear EPs to the general case; moreover, new results are obtained as well. In particular, both new results on the existence and uniqueness of solutions and new error bounds based on gap functions with good convexity properties are obtained under weak quasimonotonicity or weak concavity assumptions
- …
