Aging in coherent noise models and natural time

Event correlation between aftershocks in the coherent noise model is studied by making use of natural time, which has recently been introduced in complex time-series analysis. It is found that the aging phenomenon and the associated scaling property discovered in the observed seismic data are well reproduced by the model. It is also found that the scaling function is given by the $q$-exponential function appearing in nonextensive statistical mechanics, showing power-law decay of event correlation in natural time.Comment: 4 pages and 5 figure

Lie conformal algebra cohomology and the variational complex

We find an interpretation of the complex of variational calculus in terms of the Lie conformal algebra cohomology theory. This leads to a better understanding of both theories. In particular, we give an explicit construction of the Lie conformal algebra cohomology complex, and endow it with a structure of a g-complex. On the other hand, we give an explicit construction of the complex of variational calculus in terms of skew-symmetric poly-differential operators.Comment: 56 page

A model of large-scale proteome evolution

The next step in the understanding of the genome organization, after the determination of complete sequences, involves proteomics. The proteome includes the whole set of protein-protein interactions, and two recent independent studies have shown that its topology displays a number of surprising features shared by other complex networks, both natural and artificial. In order to understand the origins of this topology and its evolutionary implications, we present a simple model of proteome evolution that is able to reproduce many of the observed statistical regularities reported from the analysis of the yeast proteome. Our results suggest that the observed patterns can be explained by a process of gene duplication and diversification that would evolve proteome networks under a selection pressure, favoring robustness against failure of its individual components

Inovasi Pembelajaran Elektronik dan Tantangan Guru Abad 21

[Title: Electronic Learning Innovations and 21st Century Teacher Challenges]. The development of information technology that is very rapid in this century has a very significant impact on the world of education, where, the process of transition from the age of industrialization to the age of knowledge requires every field in life to change very quickly and must be able to adapt quickly. Entering the 21st-century technological advances have entered into various aspects of life, including education. Teachers and students, lecturers and students, educators and students are required to have the ability to teach in this 21st century. A number of challenges and opportunities must be faced by students and teachers in order to survive in the age of knowledge that is coloured by the emergence of various educational innovations. One innovation that is developing quite rapidly is electronic learning (electronic learning) or e-learning. E-learning is distance learning (distance learning) that utilizes computer technology, computer networks and/or the internet. This electronic learning innovation allows learners to learn through computers in their respective places without having to physically go to attend classes/lectures in class. Therefore, educators and prospective educators in the 21st century need to be prepared to be able to adapt to the development of science and technology. Teacher Training Institute (LPTK) as an institution producing prospective educators/teachers needs to equip teachers and prospective teachers to skillfully use technology, especially ICT, because of the challenges of future teachers related to ICT. In an effort to prepare prospective teachers entering the 21st century, STKIP Weetebula as one of the LPTKs in Indonesia seeks to equip its students by including e-learning courses in the curriculum of elementary school teacher education study programs (PGSD)

Preferential attachment in the protein network evolution

The Saccharomyces cerevisiae protein-protein interaction map, as well as many natural and man-made networks, shares the scale-free topology. The preferential attachment model was suggested as a generic network evolution model that yields this universal topology. However, it is not clear that the model assumptions hold for the protein interaction network. Using a cross genome comparison we show that (a) the older a protein, the better connected it is, and (b) The number of interactions a protein gains during its evolution is proportional to its connectivity. Therefore, preferential attachment governs the protein network evolution. The evolutionary mechanism leading to such preference and some implications are discussed.Comment: Minor changes per referees requests; to appear in PR

E-Learning Moodle, Media Pembelajaran Fisika Abad 21

[Title: Moodle E-Learning, the 21st Century Physics Learning Media] A distinctive characteristic of 21st-century learning is digital communication, meaning that the learning process is no longer face to face course between teachers and students but is more of an internet-based (e-learning) modern learning. The process of implementing e-learning requires a Learning Management System (LMS) which functions to regulate the management of learning. One of the LMS that can be used in organizing e-learning learning is moodle. Moodle e-learning can be used as a medium to improve the quality of interactive learning and support for the implementation of blended learning. Through e-learning moodle learning material can be accessed anytime and anywhere, besides that the material can be enriched with various learning resources including multimedia, which can be quickly updated by the instructor. In addition, the facilities offered in moodle e-learning learning are able to display learning materials that are abstract in nature into material that can be witnessed in person. Material samples that are mostly abstract are material on physics subjects. Therefore, moodle electronic learning is expected to be able to help students master the concepts in physics learning

Ab initio study of reflectance anisotropy spectra of a sub-monolayer oxidized Si(100) surface

The effects of oxygen adsorption on the reflectance anisotropy spectrum (RAS) of reconstructed Si(100):O surfaces at sub-monolayer coverage (first stages of oxidation) have been studied by an ab initio DFT-LDA scheme within a plane-wave, norm-conserving pseudopotential approach. Dangling bonds and the main features of the characteristic RAS of the clean Si(100) surface are mostly preserved after oxidation of 50% of the surface dimers, with some visible changes: a small red shift of the first peak, and the appearance of a distinct spectral structure at about 1.5 eV. The electronic transitions involved in the latter have been analyzed through state-by-state and layer-by-layer decompositions of the RAS. We suggest that new interplay between present theoretical results and reflectance anisotropy spectroscopy experiments could lead to further clarification of structural and kinetic details of the Si(100) oxidation process in the sub-monolayer range.Comment: 21 pages, 8 figures. To be published in Physical Rev.

Lagrangian phase transitions in nonequilibrium thermodynamic systems

In previous papers we have introduced a natural nonequilibrium free energy by considering the functional describing the large fluctuations of stationary nonequilibrium states. While in equilibrium this functional is always convex, in nonequilibrium this is not necessarily the case. We show that in nonequilibrium a new type of singularities can appear that are interpreted as phase transitions. In particular, this phenomenon occurs for the one-dimensional boundary driven weakly asymmetric exclusion process when the drift due to the external field is opposite to the one due to the external reservoirs, and strong enough.Comment: 10 pages, 2 figure

Students' experience of the use of an online learning channel in teaching and learning: a sports therapy perspective

Aims/Background: The inclusion of blended e-learning approaches to teaching has become more prevalent in higher education. The purpose of this paper was to examine sports therapy students’ experiences of using an online learning channel designed to assist practical skills. Moreover, creating an understanding of students’ adoption of the learning channel to determine its efficacy. Method: The design was a mixed method exploratory study in which a questionnaire was designed to investigate students’ experience of using the learning channel across all undergraduate BSc Sports Therapy modules. One-hundred and sixtyfour (level four n=67, level five n=51, level six n=46) students completed the questionnaire relating to their experience of an online video-based learning channel. Findings: BSc Sports Therapy students across all levels found the learning channel useful, with the most common responses related to revision and consolidation of practical skills. Exam preparation was associated to this suggesting students’ beliefs were driven by resources which could facilitate grade improvement in practical exams. Conclusions: The sports therapy learning channel was received very positively with both the visual and practical nature of online instructional videos deemed important

Bihamiltonian Cohomologies and Integrable Hierarchies I: A Special Case

We present some general results on properties of the bihamiltonian cohomologies associated to bihamiltonian structures of hydrodynamic type, and compute the third cohomology for the bihamiltonian structure of the dispersionless KdV hierarchy. The result of the computation enables us to prove the existence of bihamiltonian deformations of the dispersionless KdV hierarchy starting from any of its infinitesimal deformations.Comment: 43 pages. V2: the accepted version, to appear in Comm. Math. Phy