1,106 research outputs found

    Cass. Sezioni Unite 18214/2015: i giudici di legittimit\ue0 sulla \uabinterpretazione assiologicamente orientata\ubb delle nullit\ue0 per vizio di forma

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    Confermando il trend ormai piuttosto nitido che vuole il tema del formalismo negoziale il pi\uf9 interessante laboratorio di nullit\ue0 speciali, la sentenza delle Sezioni Unite qui brevemente commentata aggiunge un tassello non trascurabile n\ue9 scontato ad un dibattito ancora vivace: non tanto o non solo per l\u2019esito cui perviene nella circoscritta materia della locazione abitativa, quanto piuttosto per la disinvoltura con cui maneggia un argomento decisamente \uabcaldo\ubb del diritto dei contratti. La prima questione su cui \ue8 chiamata a pronunciarsi la Corte \ue8 di facile soluzione ma di articolata argomentazione: se per le locazioni di immobili adibiti ad uso abitativo di cui alla legge n. 431/1998 la scrittura sia da intendersi a fini di validit\ue0 o a fini di prova. La risposta \ue8 gi\ue0 nelle norme: l\u2019art. 1 co., 4 disponendo che per la stipula di validi contratti di locazione \ue8 richiesta la forma scritta, lascia chiaramente intendere che la formalizzazione dell\u2019accordo \ue8 imposta ad substantiam. I giudici colgono per\uf2 l\u2019occasione per fermarsi sulle ragioni della scelta legislativa, evocando quella prospettiva funzionale che, riguardo alla forma, \ue8 conquista recente e non del tutto pacifica della riflessione scientifica. Quanto al secondo quesito, le Sezioni Unite della Corte di Cassazione hanno affermato che il contratto di locazione ad uso abitativo stipulato senza la forma scritta \ue8 affetto da nullit\ue0 assoluta, rilevabile d\u2019ufficio, attesa la ratio pubblicistica di contrasto all\u2019evasione fiscale, eccettuata l\u2019ipotesi in cui la forma verbale sia stata imposta dal locatore, in quanto in questo caso si tratterebbe di \uabnullit\ue0 di protezione\ubb a favore del conduttore, solo da lui denunciabile. In sostanza, il conduttore \ue8 tenuto a provare la \uabviolenza morale\ubb subita e dunque l\u2019abuso: in tal caso il contratto sar\ue0 nullo, ma la nullit\ue0 \ue8 da intendersi come \uabrelativa\ubb e cio\ue8 azionabile esclusivamente da parte del conduttore. Diversamente, ove la forma orale sia liberamente concordata, la nullit\ue0 deve ritenersi assoluta, rilevabile d\u2019ufficio e non sanabile. In ogni caso, l\u2019abuso non pu\uf2 ritenersi presunto ex lege, in ragione dello squilibrio di potere contrattuale sussistente tra locatore e conduttore, ma deve invece essere provato dal conduttore

    Singular kernels, multiscale decomposition of microstructure, and dislocation models

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    We consider a model for dislocations in crystals introduced by Koslowski, Cuiti\~no and Ortiz, which includes elastic interactions via a singular kernel behaving as the H1/2H^{1/2} norm of the slip. We obtain a sharp-interface limit of the model within the framework of Γ\Gamma-convergence. From an analytical point of view, our functional is a vector-valued generalization of the one studied by Alberti, Bouchitt\'e and Seppecher to which their rearrangement argument no longer applies. Instead we show that the microstructure must be approximately one-dimensional on most length scales and exploit this property to derive a sharp lower bound

    Sharp interface limit for a phase field model in structural optimization

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    We formulate a general shape and topology optimization problem in structural optimization by using a phase field approach. This problem is considered in view of well-posedness and we derive optimality conditions. We relate the diffuse interface problem to a perimeter penalized sharp interface shape optimization problem in the sense of Γ\Gamma-convergence of the reduced objective functional. Additionally, convergence of the equations of the first variation can be shown. The limit equations can also be derived directly from the problem in the sharp interface setting. Numerical computations demonstrate that the approach can be applied for complex structural optimization problems

    Branching Structures in Elastic Shape Optimization

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    Fine scale elastic structures are widespread in nature, for instances in plants or bones, whenever stiffness and low weight are required. These patterns frequently refine towards a Dirichlet boundary to ensure an effective load transfer. The paper discusses the optimization of such supporting structures in a specific class of domain patterns in 2D, which composes of periodic and branching period transitions on subdomain facets. These investigations can be considered as a case study to display examples of optimal branching domain patterns. In explicit, a rectangular domain is decomposed into rectangular subdomains, which share facets with neighbouring subdomains or with facets which split on one side into equally sized facets of two different subdomains. On each subdomain one considers an elastic material phase with stiff elasticity coefficients and an approximate void phase with orders of magnitude softer material. For given load on the outer domain boundary, which is distributed on a prescribed fine scale pattern representing the contact area of the shape, the interior elastic phase is optimized with respect to the compliance cost. The elastic stress is supposed to be continuous on the domain and a stress based finite volume discretization is used for the optimization. If in one direction equally sized subdomains with equal adjacent subdomain topology line up, these subdomains are consider as equal copies including the enforced boundary conditions for the stress and form a locally periodic substructure. An alternating descent algorithm is employed for a discrete characteristic function describing the stiff elastic subset on the subdomains and the solution of the elastic state equation. Numerical experiments are shown for compression and shear load on the boundary of a quadratic domain.Comment: 13 pages, 6 figure

    Tightness for a stochastic Allen--Cahn equation

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    We study an Allen-Cahn equation perturbed by a multiplicative stochastic noise which is white in time and correlated in space. Formally this equation approximates a stochastically forced mean curvature flow. We derive uniform energy bounds and prove tightness of of solutions in the sharp interface limit, and show convergence to phase-indicator functions.Comment: 27 pages, final Version to appear in "Stochastic Partial Differential Equations: Analysis and Computations". In Version 4, Proposition 6.3 is new. It replaces and simplifies the old propositions 6.4-6.

    Analysis of an Inverse Problem Arising in Photolithography

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    We consider the inverse problem of determining an optical mask that produces a desired circuit pattern in photolithography. We set the problem as a shape design problem in which the unknown is a two-dimensional domain. The relationship between the target shape and the unknown is modeled through diffractive optics. We develop a variational formulation that is well-posed and propose an approximation that can be shown to have convergence properties. The approximate problem can serve as a foundation to numerical methods.Comment: 28 pages, 1 figur

    Solid microcrystalline dispersion films as a new strategy to improve the dissolution rate of poorly water soluble drugs: a case study using olanzapine

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    In this study, we evaluate the dissolution rate enhancement of solid microcrystalline dispersion (SMD) films of olanzapine (OLZ) formulated with four water-soluble polymers namely poly(N-vinylpyrrolidone) (PVP), poloxamer 188 (P188), poloxamer 407 (P407) and Soluplus(®) (SLP). Prepared formulations were characterised to determine particle size, morphology, hydrogen bonding interactions, thermal characteristics as well as in vitro dissolution studies conducted under sink conditions (pH 6.8). Particle size of OLZ in all formulations ranged between 42 and 58μm. Attenuated Total Reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR), Differential Scanning Calorimetry (DSC) and Hot-Stage Microscopy (HSM) studies confirmed OLZ was well maintained in its crystalline state during the formulation process. In vitro dissolution studies showed immediate drug release from all formulation when compared to the drug alone. The greatest increase in in vitro dissolution rate was observed in formulations containing P188 most likely due to its enhanced hydrophilic and surfactant properties compared to the other agents used. Overall, this study successfully generated OLZ loaded SMD films with improved in vitro dissolution rates which is highly likely to result in improved oral bioavailability in vivo

    Motion of a droplet for the Stochastic mass conserving Allen-Cahn equation

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    We study the stochastic mass-conserving Allen-Cahn equation posed on a smoothly bounded domain of R2 with additive, spatially smooth, space-time noise. This equation describes the stochastic motion of a small almost semicircular droplet attached to domain's boundary and moving towards a point of locally maximum curvature. We apply It^o calculus to derive the stochastic dynamics of the center of the droplet by utilizing the approximately invariant manifold introduced by Alikakos, Chen and Fusco [2] for the deterministic problem. In the stochastic case depending on the scaling, the motion is driven by the change in the curvature of the boundary and the stochastic forcing. Moreover, under the assumption of a su ciently small noise strength, we establish stochastic stability of a neighborhood of the manifold of boundary droplet states in the L2- and H1-norms, which means that with overwhelming probability the solution stays close to the manifold for very long time-scales

    Massive Star Cluster Formation and Destruction in Luminous Infrared Galaxies in GOALS

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    We present the results of a {\it Hubble Space Telescope} ACS/HRC FUV, ACS/WFC optical study into the cluster populations of a sample of 22 Luminous Infrared Galaxies in the Great Observatories All-Sky LIRG Survey. Through integrated broadband photometry we have derived ages and masses for a total of 484 star clusters contained within these systems. This allows us to examine the properties of star clusters found in the extreme environments of LIRGs relative to lower luminosity star-forming galaxies in the local Universe. We find that by adopting a Bruzual \& Charlot simple stellar population (SSP) model and Salpeter initial mass function, the age distribution of clusters declines as dN/dτ=τ0.9+/0.3dN/d\tau = \tau^{-0.9 +/- 0.3}, consistent with the age distribution derived for the Antennae Galaxies, and interpreted as evidence for rapid cluster disruption occuring in the strong tidal fields of merging galaxies. The large number of 106M10^{6} M_{\odot} young clusters identified in the sample also suggests that LIRGs are capable of producing more high-mass clusters than what is observed to date in any lower luminosity star-forming galaxy in the local Universe. The observed cluster mass distribution of dN/dM=M1.95+/0.11dN/dM = M^{-1.95 +/- 0.11} is consistent with the canonical -2 power law used to describe the underlying initial cluster mass function (ICMF) for a wide range of galactic environments. We interpret this as evidence against mass-dependent cluster disruption, which would flatten the observed CMF relative to the underlying ICMF distribution.Comment: 63 pages, 58 Figures, 56 Tables, Accepted for publication in Ap

    Therapeutic sequences in patients with grade 1−2 neuroendocrine tumors (NET): an observational multicenter study from the ELIOS group

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    Purpose: Many different treatments are suggested by guidelines to treat grade 1−2 (G1−G2) neuroendocrine tumors (NET). However, a precise therapeutic algorithm has not yet been established. This study aims at identifying and comparing the main therapeutic sequences in G1−G2 NET. Methods: A retrospective observational Italian multicenter study was designed to collect data on therapeutic sequences in NET. Median progression-free survival (PFS) was compared between therapeutic sequences, as well as the number and grade of side effects and the rate of dose reduction/treatment discontinuation. Results: Among 1182 patients with neuroendocrine neoplasia included in the ELIOS database, 131 G1–G2 gastroenteropancreatic, lung and unknown primary NET, unresectable or persistent/relapsing after surgery, treated with ≥2 systemic treatments, were included. Four main therapeutic sequences were identified in 99 patients: (A) somatostatin analogs (SSA) standard dose to SSA high dose (n = 36), (B) SSA to everolimus (n = 31), (C) SSA to chemotherapy (n = 17), (D) SSA to peptide receptor radionuclide therapy (PRRT) (n = 15). Median PFS of the second-line treatment was not reached in sequence A, 33 months in sequence B, 20 months in sequence C, 30 months in sequence D (p = 0.16). Both total number and severity of side effects were significantly higher in sequences B and C than A and D (p = 0.04), as well as the rate of dose reduction/discontinuation (p = 0.03). Conclusions: SSA followed by SSA high dose, everolimus, chemotherapy or PRRT represent the main therapeutic sequences in G1−G2 NET. Median PFS was not significantly different between sequences. However, the sequences with SSA high dose or PRRT seem to be better tolerated than sequences with everolimus or chemotherapy
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