Search results for "Elastic"
showing 10 items of 2162 documents
Electromyographic comparison of elastic resistance and machine exercises for high-intensity strength training in patients with chronic stroke
2016
To investigate whether elastic resistance training can induce comparable levels of muscle activity as conventional machine training in patients with chronic stroke.Comparative study.Outpatient rehabilitation facility.Stroke patients (N=18) with hemiparesis (mean age, 57 ± 8y).Patients performed 3 consecutive repetitions at 10 repetition maximum of unilateral knee extension and flexion using elastic resistance and conventional machine training.Surface electromyography was measured in vastus lateralis, vastus medialis, biceps femoris, and semitendinosus and was normalized to maximal electromyography (% of max) of the nonparetic leg.In the paretic leg, agonist muscle activity ranged from 18% t…
Comparison of myocardial perfusion reserve before and after coronary balloon predilatation and after stent implantation in patients with postangiopla…
1996
Background Stents provide a scaffold for coronary arteries after angioplasty and inhibit elastic recoil. Methods and Results In 25 patients with postangioplasty restenosis of the left anterior descending artery, ECG-gated digital subtraction coronary angiograms were recorded at baseline and during hyperemia (12 mg papaverine IC) before and after balloon predilatation (PTCA), after implantation of a Palmaz-Schatz stent, and after 6 months. Densitometric evaluation revealed different time and density parameters to calculate two definitions of myocardial perfusion reserve (MPR1 and MPR2) and maximum flow ratio (MaxFR). Poststenotic MPR1 increased from 1.57±0.14 to 2.59±0.86 after PTCA and to …
Relativistic corrections and unitary equivalence in elastic electron deuteron scattering.
1993
The role of unitary equivalence of relativistic corrections in elastic electron deutron scattering is studied, starting from a class of approximately, unitarily equivalent Hamiltonians and using consistent charge density operators. The connection of various formal approaches for deriving the relativistic corrections to wave functions and operators are discussed in detail. For reasons of simplicity, we have chosen a pure one-pion-exchange model and calculated the charge and quadrupole form factors of the deuteron. The numerical results show that the unitary equivalence holds at small momentum transfers, but breaks down rather soon with increasing momentum transfers (\ensuremath{\lesssim}5 ${…
Complex, energy-independent, local potential reproducing an absorptive phase shift and a bound state
1994
The triton binding energy, and the partly real and partly complex neutron-deuteron doublet channel elastic scattering phase shifts, calculated by means of the exact three-body theory, are used as input in the fixed-[ital l] inverse scattering theory of Marchenko. The local potentials obtained hereby are independent of energy, and complex. Their strong imaginary part reflects the strong absorption in the doublet channel arising from the opening of the deuteron breakup channel. For total orbital angular momentum [ital l] different from zero the potentials are unique, reproducing the input phase shift in the whole energy region. For [ital l]=0 where there exists, in addition, a bound state we …
Insights Into the Inside - A Quantitative Histological Study of the Explosively Moving Style in Marantaceae.
2018
This study aims to identify the histological basis for the extraordinary, fast movement of the style in Marantaceae. Although this explosive pollination mechanism was subject of many studies, quantitative measurements to document volumetric changes have never been conducted. Based on physical parameters and limitations (poroelastic time), the movement itself is by far too fast to be explained by turgor changes solely. Therefore, we address the hypothesis that the style contains elastic structures to store energy allowing the fast movement. We provide an experimental approach in Goeppertia bachemiana to identify histological differences of styles in various states, i.e., steady, unreleased, …
Insights Into the Inside – A Quantitative Histological Study of the Explosively Moving Style in Marantaceae
2018
This study aims to identify the histological basis for the extraordinary, fast movement of the style in Marantaceae. Although this explosive pollination mechanism was subject of many studies, quantitative measurements to document volumetric changes have never been conducted. Based on physical parameters and limitations (poroelastic time), the movement itself is by far too fast to be explained by turgor changes solely. Therefore, we address the hypothesis that the style contains elastic structures to store energy allowing the fast movement. We provide an experimental approach in Goeppertia bachemiana to identify histological differences of styles in various states, i.e., steady, unreleased, …
Is the cardholder an efficient alarm system to detect credit card incidents?
2015
There is a growing tendency in credit card industry to increase the contribution of the smallest players, the cardholders, in the detection of card incidents. This article examines whether cardholders are efficient at detecting/communicating incidents of theft, loss or fraudulent use of their cards. The analysis focuses on whether they demonstrate enough speed of response to support a risk control subsystem by the issuer. The research follows a completely new approach showing how the issue can be handled by applying the concept of elasticity, a notion just recently exported from economics to the field of statistics by linking it with the reverse hazard rate. The issue is focused on the anal…
Spatial mapping of price competition using logit-type market share models and store-level scanner-data
2009
This paper proposes a methodology to obtain reliable spatial maps of price competition using store-level scanner data. Specifically, a procedure to obtain a symmetric matrix of similarities between brands considering their substitutability depending on price variations is proposed. The matrix is derived from a market response model where price cross-effects are split into two components. The first component accounts for the fact that price variation in one brand can have different effects to price variation in other brands (ie j → j′≠j′ → j). The second component accounts for the fact that the price of each brand can have different effects across competing brands (ie j → j′≠j → j ″). The ma…
Stationary and non-stationary stochastic response of linear fractional viscoelastic systems
2012
Abstract A method is presented to compute the stochastic response of single-degree-of-freedom (SDOF) structural systems with fractional derivative damping, subjected to stationary and non-stationary inputs. Based on a few manipulations involving an appropriate change of variable and a discretization of the fractional derivative operator, the equation of motion is reverted to a set of coupled linear equations involving additional degrees of freedom, the number of which depends on the discretization of the fractional derivative operator. As a result of the proposed variable transformation and discretization, the stochastic analysis becomes very straightforward and simple since, based on stand…
Markovian approximation of linear systems with fractional viscoelastic term
2017
It is well known that the response of a linear system enforced by a Gaussian white noise is Markovian. The order of Markovianity is n-1 being n the maximum order of the derivative of the equation ruling the evolution of the system. However when a fractional operator appears, the order of Markovianity of the system becomes infinite. Then the main aim developed in the proposed paper, consists of rewriting the system with fractional term of order r with an "equivalent" one, in which the fractional operator is substituted by two classical differential terms with integer order of derivative int(r) and int(r + 1) (for a real r). In this way the fractional differential equation reverts into a clas…