Search results for "Enna"

Conformations, Transverse Fluctuations and Crossover Dynamics of a Semi-Flexible Chain in Two Dimensions

2014

We present a unified scaling description for the dynamics of monomers of a semiflexible chain under good solvent condition in the free draining limit. We consider both the cases where the contour length $L$ is comparable to the persistence length $\ell_p$ and the case $L\gg \ell_p$. Our theory captures the early time monomer dynamics of a stiff chain characterized by $t^{3/4}$ dependence for the mean square displacement(MSD) of the monomers, but predicts a first crossover to the Rouse regime of $t^{2\nu/{1+2\nu}}$ for $\tau_1 \sim \ell_p^3$, and a second crossover to the purely diffusive dynamics for the entire chain at $\tau_2 \sim L^{5/2}$. We confirm the predictions of this scaling descr…

A discussion of potential exposure metrics for use in epidemiological studies on human exposure to radiowaves from mobile phone base stations

2000

There is currently a high level of concern in many countries that exposure to radiowaves from mobile phone base stations may be hazardous to health. When investigating such suggested risks, epidemiologists need to define an exposure metric that can reliably discriminate between exposed and unexposed groups of people. We conducted a feasibility study to investigate if either short-term measurements of electric field strength, calculations of electric field strength, or distance from nearby mobile phone base stations could be used to develop a metric reflecting an individual's exposure to radiowaves. With electric field strengths in the range of 0.012-0.343 V/m, radiowaves from mobile phone b…

Acceleration of the through space S1 energy transfer rates in cofacial bisporphyrin bio-inspired models by virtue of substituents effect on the Först…

2011

The singlet k(ET) for cofacial β-octaalkylporphyrin/bis(meso-aryl)porphyrin dyads increases linearly with the gap between the donor-acceptor 0-0 fluorescence peaks at 77 K.

Computational and experimental investigation of intermolecular states and forces in the benzene-helium van der Waals complex

2003

A study of the intermolecular potential-energy surface (IPS) and the intermolecular states of the perprotonated and perdeuterated benzene–He complex is reported. From a fit to ab initio data computed within the coupled cluster singles and doubles including connected triples model for 280 interaction geometries, an analytic IPS including two- to four-body atom–atom terms is obtained. This IPS, and two other Lennard-Jones atom–atom surfaces from the literature, are each employed in dynamically exact (within the rigid-monomer approximation) calculations of J = 0 intermolecular states of the isotopomers. Rotational constants and Raman-scattering coefficients for intermolecular vibrational trans…

Mating strategies and resulting patterns in mate guarding crustaceans : an empirical and theoretical approach

2012

Because of strong costs associated with each mating event, females are usually not as available for reproduction as males at any given time. Males are therefore in competition with each other for access to receptive females, hence leading to strong sexual selection. One textbook case of such a mating system occurs in moulting crustaceans where females can only be fertilized during a short period following their moult. This has favoured the evolution male strategies to monopolize females before their period of receptivity. Such a precopulatory mate guarding is widespread among many taxa and represents one of the most striking example of males’ competitive traits favoured by sexual selection.…

Diagonal space time hadamard codes with erasure decoding algorithm

2005

A major challenge in the area of space time (ST) codes is to find codes suitable for efficient decoding, thus overcoming the problem of many existing ST code designs which require maximum-likelihood (ML) decoding. A solution could be to apply single-input single-output (SISO) channel codes and theory over temporal channel fading to the multi-input single-output (MISO) code construction and classical suboptimum decoding methods. For these purposes, an ST code construction which allows the use of efficient decoding algorithms is described. We propose a concatenated code, where the inner code is the diagonal ST Hadamard (D-STH) code with Paley constructions and the outer code is an algebraic b…

Computational thinking in programming with Scratch in primary schools: A systematic review

2020

Computer programming is being introduced in educational curricula, even at the primary school level. One goal of this implementation is to teach computational thinking (CT), which is potentially applicable in various computational problem-solving situations. However, the educational objective of CT in primary schools is somewhat unclear: curricula in various countries define learning objectives for topics, such as computer science, computing, programming or digital literacy but not for CT specifically. Additionally, there has been confusion in concretely and comprehensively defining and operationalising what to teach, learn and assess about CT in primary education even with popular programm…

Using an integrated social cognition model to predict COVID‐19 preventive behaviours

2020

ObjectivesRates of novel coronavirus disease 2019 (COVID-19) infections have rapidly increased worldwide and reached pandemic proportions. A suite of preventive behaviours have been recommended to minimize risk of COVID-19 infection in the general population. The present study utilized an integrated social cognition model to explain COVID-19 preventive behaviours in a sample from the Iranian general population.DesignThe study adopted a three-wave prospective correlational design.MethodsMembers of the general public (N = 1,718, Mage = 33.34, SD = 15.77, male = 796, female = 922) agreed to participate in the study. Participants completed self-report measures of demographic characteristics, i…

Kohti jälkifossiilista työtä

2021

The real–virtual antenna functions forS→QQ¯Xat NNLO QCD

2014

Abstract We determine, in the antenna subtraction framework for handling infrared divergences in higher order QCD calculations, the real–virtual antenna functions for processes involving the production of a pair of massive quarks by an uncolored initial state at NNLO QCD. The integrated leading and subleading color real–virtual antenna functions are computed analytically in terms of (cyclotomic) harmonic polylogarithms. As a by-product and check we compute R Q = σ ( e + e − → γ ⁎ → Q Q ¯ X ) / σ ( e + e − → γ ⁎ → μ + μ − ) and compare with existing results. Our result for R Q is exact to order α s 2 .