Walk in my shoes: college students\u27 and their parents\u27 predictions of their own health practices if they were each others\u27 age

College students and their parents completed a survey of their present health practices. They then completed the same survey for health behaviors they thought they would practice if they were either between the ages of 18 - 22 (for the parent respondents) or 45 - 55 (for the student respondents). The results generally showed the students predicted they would lead healthier lifestyles if older than their parents actually do, and the parents would lead less healthy lifestyles if younger than their children actually do. This distortion of each others\u27 health practices, however, depended to some extent on the specific health practices surveyed. The results also supported previous research showing a tendency to follow a healthier lifestyle as one ages, although once again, this finding depended on the specific health behavior surveyed

Precision Masses of the low-mass binary system GJ 623

We have used Aperture Masking Interferometry and Adaptive Optics (AO) at the Palomar 200'' to obtain precise mass measurements of the binary M dwarf GJ 623. AO observations spread over 3 years combined with a decade of radial velocity measurements constrain all orbital parameters of the GJ 623 binary system accurately enough to critically challenge the models. The dynamical masses measured are m_{1}=0.371\pm0.015 M_{\sun} (4%) and m_{2}=0.115\pm0.0023 M_{\sun} (2%) for the primary and the secondary respectively. Models are not consistent with color and mass, requiring very low metallicities.Comment: 7 pages, 5 figures. Accepted for Ap

Student and staff perceptions and experiences of the introduction of Objective Structured Practical Examinations: A pilot study

Background. The Objective Structured Practical Examination (OSPE) is widely recognised as one of the more objective methods of assessing practical skills in healthcare programmes, including undergraduate physiotherapy curricula.Objectives. To obtain feedback from both students and staff who were involved in the introduction of an OSPE in 2011, in order to refine and standardise the format throughout the curriculum.Methods. A qualitative research design was used. Data were gathered through a questionnaire with semi-structured open-ended items and focus group discussion. Participants were all third-year undergraduate physiotherapy students (N=47) and all staff members (N=10) in the 2011 academic year who were exposed to the OSPE format or were involved in the first OSPE.Results. The main concerns raised by both students and staff were: (i) pressure due to time constraints and how this might affect student performance; and (ii) the question of objectivity during the assessment. However, their initial concerns changed as they experienced the OSPE in a more positive manner owing to the structure and objectivity of the process of implementing the OSPE.Conclusion. While both students and staff reported positive experiences, the challenges that emerged provided valuable insight in terms of refining the OSPE format in this undergraduate physiotherapy department

Masses of Astrometrically-Discovered and Imaged Binaries: G 78-28AB and GJ 231.1BC

The Stellar Planet Survey (STEPS) is an ongoing astrometric search for giant planets and brown dwarfs around a sample of ~30 M-dwarfs. We have discovered several low-mass companions by measuring the motion of our target stars relative to their reference frames. The highest mass discovery thus far is G 78-28B, a companion to the M-dwarf G 78-28A. The orbital period is 4.18 +/- 0.03 y, the system mass is 0.565 +/- 0.055 Msolar, and the semi-major axis is 2.19 +/- 0.10 AU. Imaging observations with the Keck laser guide star adaptive optics (LGSAO) and the Palomar AO instruments resolved the system and also yielded JHK-band delta magnitudes. We use the orbital solution, light ratios, and mass-luminosity relationships to derive component masses of MA = 0.370 +/- 0.034 Msolar and MB = 0.195 +/- 0.021 Msolar. G 78-28B is of type M4 V based upon its colors and mass. We also discovered GJ 231.1C, a companion to GJ 231.1B, with STEPS and imaged the companion with LGSAO and Palomar AO, but the orbital period is longer than our observing baseline; thus the system parameters are less constrained. In GJ 231.1BC the masses are MB = 0.25 +/- 0.06 Msolar and MC =0.12 +/- 0.02 Msolar. The inferred spectral type of GJ 231.1C is M5 V. We demonstrate the results of the current state of mass estimation techniques with our data.Comment: 25 pages, 8 figures, accepted for Ap

The Approach to Ergodicity in Monte Carlo Simulations

The approach to the ergodic limit in Monte Carlo simulations is studied using both analytic and numerical methods. With the help of a stochastic model, a metric is defined that enables the examination of a simulation in both the ergodic and non-ergodic regimes. In the non-ergodic regime, the model implies how the simulation is expected to approach ergodic behavior analytically, and the analytically inferred decay law of the metric allows the monitoring of the onset of ergodic behavior. The metric is related to previously defined measures developed for molecular dynamics simulations, and the metric enables the comparison of the relative efficiencies of different Monte Carlo schemes. Applications to Lennard-Jones 13-particle clusters are shown to match the model for Metropolis, J-walking and parallel tempering based approaches. The relative efficiencies of these three Monte Carlo approaches are compared, and the decay law is shown to be useful in determining needed high temperature parameters in parallel tempering and J-walking studies of atomic clusters.Comment: 17 Pages, 7 Figure

Inherent-Structure Dynamics and Diffusion in Liquids

The self-diffusion constant D is expressed in terms of transitions among the local minima of the potential (inherent structure, IS) and their correlations. The formulae are evaluated and tested against simulation in the supercooled, unit-density Lennard-Jones liquid. The approximation of uncorrelated IS-transition (IST) vectors, D_{0}, greatly exceeds D in the upper temperature range, but merges with simulation at reduced T ~ 0.50. Since uncorrelated IST are associated with a hopping mechanism, the condition D ~ D_{0} provides a new way to identify the crossover to hopping. The results suggest that theories of diffusion in deeply supercooled liquids may be based on weakly correlated IST.Comment: submitted to PR

Evolution of Cu nanoclusters on Cu(100)

Abstract Using molecular dynamics simulations combined with kinetic Monte Carlo methods we have studied the evolution of copper nanoclusters on a copper (100) surface. We have developed a method for relaxing the clusters into a suitable configuration for input into the kinetic Monte Carlo method using molecular dynamics. Using kinetic Monte Carlo methods we have simulated the evolution of clusters with sizes of 22-2045 atoms at temperatures of 220-1020 K. We found that the Cu clusters on the surface will be reduced to one monolayer if given enough time to relax, and that this process shows an Arrhenius behaviour. In this paper we present the relaxation method that we developed and our observations for the evolution of the clusters

Falcon/Kyber and Dilithium/Kyber Network Stack on Nvidia’s Data Processing Unit Platform

Commercially available quantum computers are expected to reshape the world in the near future. They are said to break conventional cryptographic security mechanisms that are deeply embedded in our today’s communication. Symmetric cryptography, such as AES, will withstand quantum attacks as long as the key sizes are doubled compared to today’s key lengths. Asymmetric cryptographic procedures, e.g. RSA, however are broken. It is therefore necessary to change the way we assure our privacy by adopting and moving towards post-quantum cryptography (PQC) principles. In this work, we benchmark three PQC algorithms, Falcon, Dilithium, and Kyber. Moreover, we present an implementation of a PQC stack consisting of the algorithms Dilithium/Kyber and Falcon/Kyber which use hardware accelerators for some key functions and evaluate their performance and resource utilization. Regarding a classic server-client model, the computational load of the Dilithium/Kyber stack is distributed more equally among server and client. The stack Falcon/Kyber biases the computational challenges towards the server, hence relieving the client of performing costly operations. We found that Dilithium’s advantage over Falcon is that Dilithium’s execution is faster while the workload to be performed is distributed equally among client and server, whereas Falcon’s advantage over Dilithium lies within the small signature sizes and the unequally distributed computational tasks. In a client server model with a performance limited client (i.e. Internet-of-Things - IoT - environments) Falcon could proof useful for it constrains the computational hard tasks to the server and leaves a minimal workload to the client. Furthermore, Falcon requires smaller bandwidth, making it a strong candidate for deep-edge or IoT applications

Falcon/Kyber and Dilithium/Kyber Network Stack on Nvidia’s Data Processing Unit Platform

Commercially available quantum computers are expected to reshape the world in the near future. They are said to break conventional cryptographic security mechanisms that are deeply embedded in our today’s communication. Symmetric cryptography, such as AES, will withstand quantum attacks as long as the key sizes are doubled compared to today’s key lengths. Asymmetric cryptographic procedures, e.g. RSA, however are broken. It is therefore necessary to change the way we assure our privacy by adopting and moving towards post-quantum cryptography (PQC) principles. In this work, we benchmark three PQC algorithms, Falcon, Dilithium, and Kyber. Moreover, we present an implementation of a PQC stack consisting of the algorithms Dilithium/Kyber and Falcon/Kyber which use hardware accelerators for some key functions and evaluate their performance and resource utilization. Regarding a classic server-client model, the computational load of the Dilithium/Kyber stack is distributed more equally among server and client. The stack Falcon/Kyber biases the computational challenges towards the server, hence relieving the client of performing costly operations. We found that Dilithium’s advantage over Falcon is that Dilithium’s execution is faster while the workload to be performed is distributed equally among client and server, whereas Falcon’s advantage over Dilithium lies within the small signature sizes and the unequally distributed computational tasks. In a client server model with a performance limited client (i.e. Internet-of-Things - IoT - environments) Falcon could proof useful for it constrains the computational hard tasks to the server and leaves a minimal workload to the client. Furthermore, Falcon requires smaller bandwidth, making it a strong candidate for deep-edge or IoT applications