Comments on "Solar System constraints to general f(R) gravity"

We comment on, and complete, the analysis of the weak field limit of metric f(R) gravity in T. Chiba, T.L. Smith, and A.L. Erickcek, Phys. Rev. D 75, 124014 (2007).Comment: 2 latex pages, to appear in the Comments section of Phys. Rev. D. A statement corrected, acknowledgments update

Gilles Tremblay pédagogue vu par ses anciens élèves : Questionnaire réalisé par courriel

Réalisée au mois de juin 2010 par l’entremise du courriel, l’enquête proposée ici vise à jeter un éclairage sur les classes d’analyse et de composition de Gilles Tremblay au Conservatoire de musique de Montréal. Neuf anciens étudiants de Tremblay, répartis sur plus de trois décennies, ont accepté de se prêter au jeu d’un retour dans le temps : Michel Gonneville, Gilbert Patenaude, Alain Lalonde, Louise Samson, André Villeneuve, Silvio Palmieri, Marc Hyland, Sean Pepperall et Annick-Patricia Carrière. Grâce à leur témoignage, on en sait aujourd’hui un peu plus sur l’organisation des cours de Tremblay. En outre, les anciens étudiants ont été interrogés sur les façons dont Tremblay structurait ses cours, la matière étudiée, les étapes franchies dans l’analyse des oeuvres, l’orientation dans le travail créatif, l’apport des collaborations externes, etc. En définitive, malgré la distance creusée par le temps, le souvenir reste vif et montre l’expérience singulière qui a pu se dégager dans le travail de guide auquel Tremblay le pédagogue s’est adonné. De sorte qu’on commence à peine à jauger le rôle fondateur qu’ont joué ses classes au sein de la modernité musicale québécoise.An email survey was conducted in June 2010 aimed at shedding light on the analysis and composition classes of Gilles Tremblay at the Montreal Conservatory of Music. Nine former students of Tremblay, spanning of three decades, agreed to participate: Michel Gonneville, Gilbert Patenaude, Alain Lalonde, Louise Samson, André Villeneuve, Silvio Palmieri, Marc Hyland, Sean Pepperall and Annick-Patricia Carrière. Thanks to their contributions, we know now a little more about the organization of Tremblay’s courses. The former students were also asked about the ways in which Tremblay structured his courses, the topics covered, the steps taken in analysing works, his creative direction, the contribution of outside collaborators, etc. Despite the years, the memories remain vivid and are a testimony to the singular experience of Tremblay’s teaching and his unique pedagogical role, so apparent in the development of modern music in Québec

Informal Thinkering: How Is It Important?

This paper examines innovation processes or technical change-generation processes at the firm level. It emphasizes the notion that the element of technical and technological change that is a determinant of productivity growth is strongly induced by internal factors related to the firm's behavior, via investment in R&D but also, and importantly, on the basis of informal thinkering within plants. This research is unique in that it seeks first, to examine the pattern of technical change and its ensuing productivity growth, and second, to make a comparison between an industrialized and an industrializing country. This comparison is conducted by empirically comparing mills in the pulp and paper manufacturing sector in two countries: Canada and India. The overall analysis is based on direct observations at the mill level, face-to-face interviews and on analysis of mill documentary records. This paper highlights the importance of managing change as a continuous process. The introduction of intermittent, step-jump technical changes contributed little to explain the differences in performance between the mills. Much more important are (i) the continuing sequences of smaller investments in technical change, often linked to the larger step-jumps, and (ii) the existence of steady streams of changes and improvements that are unrecorded as capital expenditure Cet article examine des processus d'innovation ou de génération de changements techniques au niveau de la firme. Il met l'emphase sur le fait que les paramètres clés connexes aux changements techniques et technologiques ayant un impact sur la croissance de productivité sont induits par des facteurs behavioraux internes à la firme. Les changements peuvent être le résultat d'investissement dans la R&D,0501s aussi, et de façon significative, le résultat de processus de conceptions informelles à l'intérieur des firmes. Cette recherche examiner dans un premier temps des processus de changements techniques et la croissance de productivité en résultant. Dans un deuxième temps, elle fait une analyse comparative entre pays industrialisés et s'industrialisant. Cette étude empirique est basée sur des données de première0501n (observations directes, entrevues personnelles, documents internes) collectées dans neuf usines de pâtes et papiers dans deux pays (Canada et Inde). Ce papier met en évidence l'importance de gérer le changement comme un processus continu. L'introduction de changements techniques par sauts intermittents contribue peu à expliquer les différences de croissance de productivité entre les usines. Plus significatives sont (i) les séquences continues de petits investissements (changements techniques), souvent liés aux plus grands changements par sauts, et (ii) l'existence d'un flux continu de changements et d'améliorations qui ne sont pas officiellement enregistrés (aux livres, de façon comptable) comme des investissements en capitaux.Technical change, incremental change, performance measure-ment, continuous improvement, capital investment, pulp and paper, India, Canada, Changement technique, changements par incréments, mesures de performance, amélioration continue, investment capital, pâtes et papiers, Inde, Canada

Multifractality of self-avoiding walks on percolation clusters

We consider self-avoiding walks (SAWs) on the backbone of percolation clusters in space dimensions d=2, 3, 4. Applying numerical simulations, we show that the whole multifractal spectrum of singularities emerges in exploring the peculiarities of the model. We obtain estimates for the set of critical exponents, that govern scaling laws of higher moments of the distribution of percolation cluster sites visited by SAWs, in a good correspondence with an appropriately summed field-theoretical \varepsilon=6-d-expansion (H.-K. Janssen and O. Stenull, Phys. Rev. E 75, 020801(R) (2007)).Comment: 4 page

Shrinking a large dataset to identify variables associated with increased risk of Plasmodium falciparum infection in Western Kenya

Large datasets are often not amenable to analysis using traditional single-step approaches. Here, our general objective was to apply imputation techniques, principal component analysis (PCA), elastic net and generalized linear models to a large dataset in a systematic approach to extract the most meaningful predictors for a health outcome. We extracted predictors for Plasmodium falciparum infection, from a large covariate dataset while facing limited numbers of observations, using data from the People, Animals, and their Zoonoses (PAZ) project to demonstrate these techniques: data collected from 415 homesteads in western Kenya, contained over 1500 variables that describe the health, environment, and social factors of the humans, livestock, and the homesteads in which they reside. The wide, sparse dataset was simplified to 42 predictors of P. falciparum malaria infection and wealth rankings were produced for all homesteads. The 42 predictors make biological sense and are supported by previous studies. This systematic data-mining approach we used would make many large datasets more manageable and informative for decision-making processes and health policy prioritization

Commensurate and Incommensurate Structure of the Neutron Cross Section in LaSrCuO and YBaCuO

We study the evolution of the d-wave neutron cross-section with variable frequency \omega and fixed T (below and above Tc) in two different cuprate families. The evolution from incommensurate to commensurate to incommensurate peaks is rather generic within an RPA-like scheme. This behavior seems to be in reasonable accord with experiments, and may help distinguish between this and the "stripe" scenario.Comment: 2 pages; submitted to Proceedings of M2S-HTSC-V