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1.
Ottavia Colombo Simona Villani Giovanna Pinelli Claudia Trentani Maurizia Baldi Orazio Tomarchio Anna Tagliabue 《Nutrition journal》2008,7(1):5
Background
Excess body fat is a major risk factor for disease primarily due to its endocrine activity. In recent years several criteria have been introduced to evaluate this factor. Nevertheless, treatment need is currently assessed only on the basis of an individual's Body Mass Index (BMI), calculated as body weight (in kg) divided by height in m2. The aim of our study was to determine whether application of the BMI, compared to adiposity-based criteria, results in underestimation of the number of subjects needing lifestyle intervention. 相似文献2.
The structure of the nonlinear H∞-filter in the neighborhood of the estimated trajectory is investigated and a bound on the size of the neighborhood that allows this structure is determined, both for finite and infinite horizons. Riccati inequalities that depend on the estimated trajectory are derived for finding the filter gain matrix and an algorithm for calculating the bound on the size of the above neighborhood is presented. Explicit formulas are obtained in the infinite horizon case for the minimum achievable disturbance attenuation level, the size of the neighborhood, and the corresponding filter gain. 相似文献
3.
This paper deals with the non-linear analysis of multilayered axially compressed plates in the static elastic conservative cases. A finite element model based on a Reissner-Mindlin theory involving von Kármán nonlinearity is developed. Results related to the classical Kirchhoff plate approximations are obtained via application of a penalty technique to the shear correction factor. The numerical investigations have concerned the large deflections and postbuckling behaviour of symmetrically and non-symmetrically anisotropic flat panels. The main conclusions are: (1) the non-linear effects very much depend on lay-up and boundary conditions, moreover for the asymmetric laminated long plates the snapping-type instability occurs; (2) the shear deformation effects are very much subordinate to both multilayered lay-up and load levels, furthermore they are greater in the large deflections field; (3) it has been observed that in the neighbourhood of a singularity (of buckling point type) of the tangent stiffness matrix, the use of an arc-length type algorithm could lead to a new buckled path and that happens without employing an appropriate turning bifurcation algorithm with an accompanying eigenvalues calculation, but via a non-convergent iteration in the loadstep. 相似文献
4.
Emilia Nowaczyk 《Electrical Engineering (Archiv fur Elektrotechnik)》2007,89(5):419-424
The paper presents the results of investigations into several methods of calculating the active power value from current and
voltage signal samples. The accuracy attainable for nonsinusoidal signals whose frequency differs from the nominal one was
determined. A new active power calculation method ensuring accurate results for sampling over two signal periods is proposed.
The method uses a very simple computing algorithm. 相似文献
5.
Emilia Piosik Marta Ziegler-Borowska Dorota Cheminiak-Dudkiewicz Tomasz Martyski 《International journal of molecular sciences》2021,22(5)
An adsorption process of magnetite nanoparticles functionalized with aminated chitosan (Fe3O4-AChit) showing application potential in nanomedicine into cell membrane models was studied. The cell membrane models were formed using a Langmuir technique from three selected phospholipids with different polar head-groups as well as length and carbon saturation of alkyl chains. The research presented in this work reveals the existence of membrane model composition-dependent regulation of phospholipid-nanoparticle interactions. The influence of the positively charged Fe3O4-AChit nanoparticles on a Langmuir film stability, phase state, and textures is much greater in the case of these formed by negatively charged 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DPPG) than those created by zwitterionic 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine (POPC). The adsorption kinetics recorded during penetration experiments show that this effect is caused by the strongest adsorption of the investigated nanoparticles into the DPPG monolayer driven very likely by the electrostatic attraction. The differences in the adsorption strength of the Fe3O4-AChit nanoparticles into the Langmuir films formed by the phosphatidylcholines were also observed. The nanoparticles adsorbed more easily into more loosely packed POPC monolayer. 相似文献
6.
Anita Romanowska Katarzyna Wgrzyn Katarzyna Bury Emilia Sikorska Aleksandra Gnatek Agnieszka Piwkowska Igor Konieczny Adam Lesner Magdalena Wysocka 《International journal of molecular sciences》2021,22(5)
The present study aimed to synthesize novel polycationic polymers composed of N-substituted L-2,3-diaminopropionic acid residues (DAPEGs) and investigate their cell permeability, cytotoxicity, and DNA-binding ability. The most efficient cell membrane-penetrating compounds (O2Oc-Dap(GO2)n-O2Oc-NH2, where n = 4, 6, and 8) showed dsDNA binding with a binding constant in the micromolar range (0.3, 3.4, and 0.19 µM, respectively) and were not cytotoxic to HB2 and MDA-MB-231 cells. Selected compounds used in the transfection of a GFP plasmid showed high transfection efficacy and minimal cytotoxicity. Their interaction with plasmid DNA and the increasing length of the main chain of tested compounds strongly influenced the organization and shape of the flower-like nanostructures formed, which were unique for 5/6-FAM-O2Oc-[Dap(GO2)]8-O2Oc-NH2 and typical for large proteins. 相似文献
7.
Fernando Corvillo Laura Gonzlez-Snchez Alberto Lpez-Lera Emilia Arjona Giovanni Ceccarini Ferruccio Santini David Araújo-Vilar Rebecca J Brown Joan Villarroya Francesc Villarroya Santiago Rodríguez de Crdoba Teresa Caballero Pilar Nozal Margarita Lpez-Trascasa 《International journal of molecular sciences》2021,22(12)
8.
Alfonso Ranalli Luciano Pollastri Stefania Contento Emilia Iannucci Lucia Lucera 《European Journal of Lipid Science and Technology》2003,105(2):57-67
The influence of the olive paste malaxation time on the composition and the industrial output of oil was investigated. To this purpose, three Italian olive varieties (Leccino, Dritta, Caroleo) were processed with a centrifugal system for six malaxation periods (0, 15, 30, 45, 60 and 75 min). The concentrations of the majority of the oil constituents changed during the malaxation. However, these changes were not significant for all of them: the contents of β‐carotene, the major xanthophylls, chlorophylls a and b, pheophytins a and b in the oils increased progressively with increasing malaxing times, whereas the contents of simple and hydrolysable phenols (secoiridoid derivatives), o‐diphenols and total phenols decreased. A significant increase in total volatiles and green volatiles of the lipoxygenase cascade (C6 aldehydes, C6 alcohols, C5 alcohols and C5 carbonyls) was detected. An opposite trend was observed for the green C6 esters. As a result, the global analytical quality, flavour, aroma and shelf‐life of the oils were negatively affected. The oil yield increased substantially up to 45 min of paste malaxation times. Beyond 60 min, the yields tended to decrease. 相似文献
9.
10.
Sergio S��nchez Garc��a Ana G��mez Oliva Emilia P��rez Belleboni Iv��n Pau de la Cruz 《International Journal of Information Security》2011,10(6):351-372
At present, many countries allow citizens or entities to interact with the government outside the telematic environment through
a legal representative who is granted powers of representation. However, if the interaction takes place through the Internet,
only primitive mechanisms of representation are available, and these are mainly based on non-dynamic offline processes that
do not enable quick and easy identity delegation. This paper proposes a system of dynamic delegation of identity between two
generic entities that can solve the problem of delegated access to the telematic services provided by public authorities.
The solution herein is based on the generation of a delegation token created from a proxy certificate that allows the delegating
entity to delegate identity to another on the basis of a subset of its attributes as delegator, while also establishing in
the delegation token itself restrictions on the services accessible to the delegated entity and the validity period of delegation.
Further, the paper presents the mechanisms needed to either revoke a delegation token or to check whether a delegation token
has been revoked. Implications for theory and practice and suggestions for future research are discussed. 相似文献