Arnold maps with noise: Differentiability and non-monotonicity of the rotation number

Arnold's standard circle maps are widely used to study the quasi-periodic route to chaos and other phenomena associated with nonlinear dynamics in the presence of two rationally unrelated periodicities. In particular, the El Nino-Southern Oscillation (ENSO) phenomenon is a crucial component of climate variability on interannual time scales and it is dominated by the seasonal cycle, on the one hand, and an intrinsic oscillatory instability with a period of a few years, on the other. The role of meteorological phenomena on much shorter time scales, such as westerly wind bursts, has also been recognized and modeled as additive noise. We consider herein Arnold maps with additive, uniformly distributed noise. When the map's nonlinear term, scaled by the parameter $\epsilon$, is sufficiently small, i.e. $\epsilon < 1$, the map is known to be a diffeomorphism and the rotation number $\rho_{\omega}$ is a differentiable function of the driving frequency $\omega$. We concentrate on the rotation number's behavior as the nonlinearity becomes large, and show rigorously that $\rho _{\omega }$ is a differentiable function of $\omega$, even for $\epsilon \geq 1$, at every point at which the noise-perturbed map is mixing. We also provide a formula for the derivative of the rotation number. The reasoning relies on linear-response theory and a computer-aided proof. In the diffeomorphism case of $\epsilon <1$, the rotation number $\rho_{\omega }$ behaves monotonically with respect to $\omega$. We show, using again a computer-aided proof, that this is not the case when $\epsilon \geq 1$ and the map is not a diffeomorphism.Comment: Electronic copy of final peer-reviewed manuscript accepted for publication in the Journal of Statistical Physic

Teachers’ experiences preparing to teach a new senior secondary school (psychology) curriculum on the eve of enactment

This article explores teachers’ experiences in preparing to enact a new senior secondary school subject, psychology, in Queensland, Australia, at a time of major curriculum reform. In this study, 62 teachers completed an online survey about their experiences on the eve of enactment. From an ecological lens, data were analyzed via descriptive statistics and content analysis before thematic analysis of open-ended responses. Teachers described their preparation in terms of excitement and anticipation in establishing a new subject; frustration and urgency for support to plan, collaborate and access professional learning and curriculum materials; and feelings of isolation and desire to connect with other teachers. Sustained efforts from schools, curriculum authorities and other external contexts to work in tandem with teachers are needed to enable teachers, as professionals, to prepare to enact the curriculum and set the foundations for establishing this new subject

Mesotherapy versus Systemic Therapy in the Treatment of Acute Low Back Pain: A Randomized Trial

Pharmacological therapy of back pain with analgesics and anti-inflammatory drugs is frequently associated with adverse effects, particularly in the elderly. Aim of this study was to compare mesotherapic versus conventional systemic administration of nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids in patients with acute low back pain. Eighty-four patients were randomized to receive anti-inflammatory therapy according to the following protocols: (a) mesotherapy group received the 1st and 4th day 2% lidocaine (1 mL) + ketoprofen 160 mg (1 mL) + methylprednisolone 40 mg (1 mL), then on 7th, 10th, and 13th day, 2% lidocaine (1 mL) + ketoprofen 160 mg (1 mL) + methylprednisolone 20 mg (1 mL) (b) conventional therapy group received ketoprofen 80 mg × 2/die and esomeprazole 20 mg/die orally for 12 days, methylprednisolone 40 mg/die intramuscularly for 4 days, followed by methylprednisolone 20 mg/die for 3 days, and thereafter, methylprednisolone 20 mg/die at alternate days. Pain intensity and functional disability were assessed at baseline (T0), at the end of treatment (T1), and 6 months thereafter (T2) by using visual analogic scale (VAS) and Roland-Morris disability questionnaire (RMDQ). In both groups, VAS and RMDQ values were significantly reduced at the end of drug treatment and after 6 months, in comparison with baseline. No significant differences were found between the two groups. This suggests that mesotherapy may be a valid alternative to conventional therapy in the treatment of acute low back pain with corticosteroids and NSAIDs

On the Collision Property of Chaotic Iterations Based Post-Treatments over Cryptographic Pseudorandom Number Generator

International audienceThere is not a proper mathematical definition of chaos, we have instead a quite big amount of definitions, each of one describes chaos in a more or less general context. Taking in account this, it is clear why it is hard to design an algorithm that produce random numbers, a kind of algorithm that could have plenty of concrete appliceautifat (anul)d bions. However we must use a finite state machine (e.g. a laptop) to produce such a sequence of random numbers, thus it is convenient, for obvious reasons, to redefine those aimed sequences as pseudorandom; also problems arise with floating point arithmetic if one wants to recover some real chaotic property (i.e. properties from functions defined on the real numbers). All this considerations are synthesized in the problem of the Pseudorandom number generators (PRNGs). A solution to these obstacles may be to post-operate on existing PRNGs to improve their performances, using the so-called chaotic iterations, i.e., specific iterations of a boolean function and a shift operator that use the inputted generator. This approach leads to a mathematical description of such PRNGs as discrete dynamical systems, on which chaos properties can be investigated using mathematical topology and measure theory. Such properties are well-formulated, and they allow us to characterize which functions improves the sensitivity to the seed, the expansivity, the ergodicity, or the topological mixing of the generator resulting from such a post-processing. Experience shows that choosing relevant boolean functions in these chaotic iterations improves the randomness of the inputted generator, for instance when considering the number of statistical tests of randomness passed successfully. If we focus on the cryptographical application of PRNGs, there are two main classical notions to be considered, namely collision and avalanche effect. In this article, we recall the chaotic properties of the proposed post-treatment and we study the collision property in families of pseudorandom sequences produced by this process

Social Network eTutela Della Persona

2010 - 2011Nata dall’esigenza di indagare le più recenti problematiche emerse dai nuovi scenari individuabili in Rete, la tesi Social network e tutela della persona si sviluppa inizialmente lungo tre assi: quello diritti della personalità, nello scenario di una società rinnovata e che sempre più è andata definendosi con il trascorrere degli anni dell’informazione e della comunicazione; quello del contratto elettronico, i cui capisaldi ad oggi restano sanciti dalla direttiva 2000/31/Ce; quello della responsabilità civile on-line e del ruolo giocato in tale contesto dalla figura dell'intermediario. Tali direttive, tracciate in quella che compone la prima sezione della tesi, sono andate di seguito ricomponendosi nella seconda delle aree in cui il lavoro è suddiviso, dedicata innanzitutto ad una indagine delle varie fattispecie di reato che, con riferimento alla persona e all'inviolabilità della medesima, è possibile individuare all’interno delle dinamiche proprie dei social network (oramai diffusi in qualsiasi ambito della società, sia esso privato, commerciale o pubblico). Infine, il capitolo conclusivo punta a formulare alcune delle soluzioni che, con riferimento ai vari istituti indicati, potrebbero essere prese in considerazione in vista di una organica e strutturale regolamentazione degli illeciti e delle anomalie fino ad ora riscontrati. Ovviamente non sono state trascurate, in tale percorso, le iniziative e le proposte oramai da diverso tempo al vaglio delle istituzioni internazionali; né tuttavia è stata messe in discussione la validità dei vecchi istituti o delle categorie civilistiche tradizionali, semmai ipotizzandone al più una reinterpretazione alla luce tanto delle nuove e specifiche normative, quanto anche degli ulteriori principi riconducibili al diritto comunitario ed internazionale. Dalle valutazioni effettuate risulta dunque ancora aperto un ampio dibattito sull’approccio più idoneo circa quel patrimonio di diritti che ognuno porta con sé nelle varie attività svolte in Rete, nonché sulle caratteristiche del modello più adatto a governare la stessa; un dibattito che si spera foriero di soluzioni in grado di garantire al più presto una efficace ed appropriata tutela dei diritti fondamentali, nonché capaci di consentire (alla luce di tutte le evoluzioni della Rete che, come è facile prevedere, non tarderanno a sopraggiungere) una opportuna promozione dello sviluppo della persona sotto ogni aspetto della sua esistenza. [a cura dell'autore]X n.s

“Taking the most delicate care”: Beginnings of a Mentoring Relationship between Teachers and Coaches in an Australian School

We explore the beginnings of professional coaching/mentoring relationships between teachers and university mentors in an Australian school. Often overlooked, initial steps are crucial, holding the seeds of eventual success or failure. Our mentoring program was undertaken in a large, independent, co-educational school in suburban Melbourne, Victoria. In our constructivist study, underpinned by our desire to explore on the lived experiences of others, we report on the understandings of three of the mentors/researchers and the teachers that they worked with. We gathered data from teacher-written statements and mentor journals. Using thematic analysis, we developed our findings, performing epoché as we hold both insider and outsider mentor/researcher perspectives. We present our findings under two broad headings: The prior understandings held by all and addresses positions, assertions and anticipations; and First meetings, finding accords, noticing resistances, and recognizing difficulties. We found that the apparent simplicity of first steps masked great complexity. No one entered the first meeting as an “empty vessel.” Some relationships were more problematic than others. Our goals as transformational educator/mentors were to foster deep collaborative, professional relationships with our mentees but were hampered by inherent differences of understanding with the school who sought transactional coaches. Clarity in intent from the outset is crucial to program success

diffBUM-HMM:A robust statistical modeling approach for detecting RNA flexibility changes in high-throughput structure probing data

Advancing RNA structural probing techniques with next-generation sequencing has generated demands for complementary computational tools to robustly extract RNA structural information amidst sampling noise and variability. We present diffBUM-HMM, a noise-aware model that enables accurate detection of RNA flexibility and conformational changes from high-throughput RNA structure-probing data. diffBUM-HMM is widely compatible, accounting for sampling variation and sequence coverage biases, and displays higher sensitivity than existing methods while robust against false positives. Our analyses of datasets generated with a variety of RNA probing chemistries demonstrate the value of diffBUM-HMM for quantitatively detecting RNA structural changes and RNA-binding protein binding sites

Indications for flexible fiberoptic bronchoscopy and its safety in the very elderly

Aim. To evaluate the indications and the safety of fiberoptic bronchoscopy (FOB) with bronchoalveolar lavage (BAL), protected specimen brushing (PSB), endobronchial biopsy (EBB), and transbronchial biopsy (TBB) in a population of very elderly patients. Methods. We performed a retrospective study of all adult patients, aged 50 years or older, who underwent FOB in the Bronchology Unit of the University of Parma Hospital between 1 January, 2003 and 31 April, 2005. Bronchoscopy records of 436 consecutive patients, including 191 patients, 75 yrs of age and older ("very elderly"; =&gt;75 yrs), were reviewed. Results. Patients aged 75 years were no different with regard to gender, BMI, baseline FEV1/FVC ratio, baseline SaO2, and blood pressure. The primary indication in patients aged &lt;75 years, was to assist in the diagnosis of a pulmonary mass of unknown aetiology (33%) and to remove secretions in the very elderly patients (31%). Indications for FOB and sampling procedures in the two groups were similar. Approximately 30% of patients in each group required supplemental oxygen during the procedure and fever occurred in 9.2% and 10.3% of patients, respectively.Hypertension and bleeding were relatively rare and did not occur more often in the very elderly. Conclusions. Indication for FOB did not vary with age and adverse events in both groups were uncommon and generally not severe