Search results for "STRESS"

Local Buckling of reinforcing steel bars in RC members under compression forces

2018

Buckling of longitudinal bars is a brittle failure mechanism, often recorded in reinforced concrete (RC) structures after an earthquake. Studies in the literature highlights that it often occurs when steel is in the post elastic range, by inducing a modification of the engineered stress-strain law of steel in compression. A proper evaluation of this effect is of fundamental importance for correctly evaluating capacity and ductility of structures. Significant errors can be obtained in terms of ultimate bending moment and curvature ductility of an RC section if these effects are not accounted, as well as incorrect evaluations are achieved by non-linear static analyses. This paper presents a n…

Analisi delle relazioni tra indici di stato idrico e firme spettrali in piante adulte di olivo (Olea europea L.)

2009

In Vitro Bioactivity of Astaxanthin and Peptides from Hydrolisates of Shrimp (Parapenaeus longirostris) By-Products: From the Extraction Process to B…

2021

Non-edible parts of crustaceans could be a rich source of valuable bioactive compounds such as the carotenoid astaxanthin and peptides, which have well-recognized beneficial effects. These compounds are widely used in nutraceuticals and pharmaceuticals, and their market is rapidly growing, suggesting the need to find alternative sources. The aim of this work was to set up a pilot-scale protocol for the reutilization of by-products of processed shrimp, in order to address the utilization of this valuable biomass for nutraceutical and pharmaceuticals application, through the extraction of astaxanthin-enriched oil and antioxidant-rich protein hydrolysates. Astaxanthin (AST) was obtained using …

In-vitro antioxidant capacity and cytoprotective/cytotoxic effects upon Caco-2 cells of red tilapia (Oreochromis spp.) viscera hydrolysates.

2019

Abstract The antioxidant capacity of red tilapia viscera hydrolysates (RTVH) with different degrees of hydrolysis (DH) as well as their ultrafiltration membrane fractions, were analyzed using different chemical assays. Their protective effects against oxidative stress were evaluated using H2O2-stressed human intestinal differentiated Caco-2. The highest antioxidant capacity was obtained with a DH of 42.5% (RTVH-A) and its

Wind forcing and fate of <i>Sardinella aurita</i> eggs and larvae in the Sicily Channel (Mediterranean Sea)

2015

Abstract. Multidisciplinary studies are recently seeking to define diagnostic tools for fishery sustainability by coupling ichthyoplanktonic datasets, physical and bio-geochemical oceanographic measurements, and ocean modelling. The main goal of these efforts is the understanding of those processes that control fate and dispersion of fish larvae and eggs and thus tune the inter-annual variability of biomass of fish species. We here analyzed eggs and larvae distribution and biological features of Sardinella aurita in the northeast sector of the Sicily Channel (Mediterranean Sea) collected during the 2010 and 2011 summer cruises. We make use of satellite sea surface temperature, wind, and chl…

Latvijas Republikas nozīmes pilsētu fiskālā stāvokļa novērtējums 2008.-2017. gadā

2019

Nereti iemesls valsts ekonomiskajai krīzei ir pašvaldību finansiālās problēmas. Tomēr lielākajā daļā Eiropas valstu, arī Latvijā, pašvaldību fiskālā stāvokļa novērtēšana netiek tik strikti veikta un regulēta kā tas notiek nacionālā līmenī. Darba mērķis ir noskaidrot, kāds ir deviņu Latvijas republikas nozīmes pilsētu fiskālais stāvoklis no 2008. līdz 2017. gadam, izmantojot fiskālā stāvokļa testus. Tiek veikta arī fiskālā stāvokļa prognozēšana, ņemot vērā sociālekonomisko, tostarp, demogrāfisko, faktoru tendences. Pētījuma rezultāti norāda, ka republikas nozīmes pilsētu fiskālais stāvoklis ir atšķirīgs – sastopama gan fiskālā veselība, gan fiskālais stress.

The importance of correct implants positioning and masticatory load direction on a fixed prosthesis

2018

Background Through the biomechanical study of dental implants, it is possible to understand the dissipation effects of masticatory loads in different situations and prevent the longevity of osseointegration. Aims: To evaluate the microstrains generated around external hexagon implants, using axial and non-axial loads in a fixed four-element prosthesis with straight implants and implants inclined at 17°. Material and Methods Three implants were modeled using CAD software following the manufacturer's measurements. Then, implants were duplicated and divided into two groups: one with straight implants and respective abutments, and the other with angled implants at 17° and respective abutments. …

Experimental analysis of the effect of vegetation on flow and bed shear stress distribution in high-curvature bends

2016

The cross-sectional circulation, which develops in meandering bends, exerts an important role in velocity and the boundary shear stress redistributions. This paper considers the effect of vegetation on cross-sectional flow and bed shear distribution along a high-curvature bend. The analysis is conducted with the aid of data collected in a large-amplitude meandering flume during a reference experiment without vegetation and an experiment with vegetation on the bed. The results show that the presence of vegetation modifies the curvature-induced flow pattern and the directionality of turbulent structures. In fact, in the presence of vegetation, the turbulent structures tend to develop within a…

Effects of irregular two-dimensional and three-dimensional surface roughness in turbulent channel flows

2012

Abstract Wall-resolved Large Eddy Simulation of fully developed turbulent channel flows over two different rough surfaces is performed to investigate on the effects of irregular 2D and 3D roughness on the turbulence. The two geometries are obtained through the superimposition of sinusoidal functions having random amplitudes and different wave lengths. In the 2D configuration the irregular shape in the longitudinal direction is replicated in the transverse one, while in the 3D case the sinusoidal functions are generated both in streamwise and spanwise directions. Both channel walls are roughened in such a way as to obtain surfaces with statistically equivalent roughness height, but different…

Heat and mass flows coupled with stress in a continuous medium

1996

Abstract The present paper is concerned with the formulation of the generalization of theories describing heat and mass flows in a continuous medium. The considerations are based on the non-equilibrium thermodynamics. As a result the fundamental equations for the mass and heat fluxes and for the thermodynamic and mechanical fields, are obtained and the corresponding set of differential equations is formulated. Certain differences are pointed out between the general theories presented here and the thermodiffusion theory and the theory of mixtures. A thermodynamic variational principle is constructed. All the investigations concern only flows with a single temperature field. Copyright © 1996 …