Network information and connected correlations

Entropy and information provide natural measures of correlation among elements in a network. We construct here the information theoretic analog of connected correlation functions: irreducible $N$--point correlation is measured by a decrease in entropy for the joint distribution of $N$ variables relative to the maximum entropy allowed by all the observed $N-1$ variable distributions. We calculate the ``connected information'' terms for several examples, and show that it also enables the decomposition of the information that is carried by a population of elements about an outside source.Comment: 4 pages, 3 figure

Measurement of the Associated γ+μ±\gamma + \mu^\pm Production Cross Section in ppˉp \bar p Collisions at s=1.8\sqrt{s} = 1.8 TeV

We present the first measurement of associated direct photon + muon production in hadronic collisions, from a sample of 1.8 TeV $p \bar p$ collisions recorded with the Collider Detector at Fermilab. Quantum chromodynamics (QCD) predicts that these events are primarily from the Compton scattering process $cg \to c\gamma$, with the final state charm quark producing a muon. Hence this measurement is sensitive to the charm quark content of the proton. The measured cross section of $29\pm 9 pb^{-1}$ is compared to a leading-order QCD parton shower model as well as a next-to-leading-order QCD calculation.Comment: 12 pages, 4 figures Added more detailed description of muon background estimat

Search for the Supersymmetric Partner of the Top-Quark in ppˉp \bar{p} Collisions at s=1.8TeV\sqrt{s} = 1.8 {\rm TeV}

We report on a search for the supersymmetric partner of the top quark (stop) produced in $t \bar{t}$ events using $110 {\rm pb}^{-1}$ of $p \bar{p}$ collisions at $\sqrt{s} = 1.8 {\rm TeV}$ recorded with the Collider Detector at Fermilab. In the case of a light stop squark, the decay of the top quark into stop plus the lightest supersymmetric particle (LSP) could have a significant branching ratio. The observed events are consistent with Standard Model $t \bar{t}$ production and decay. Hence, we set limits on the branching ratio of the top quark decaying into stop plus LSP, excluding branching ratios above 45% for a LSP mass up to 40 {\rm GeV/c}$^{2}$.Comment: 11 pages, 4 figure

Measurement of the B0 anti-B0 oscillation frequency using l- D*+ pairs and lepton flavor tags

The oscillation frequency Delta-md of B0 anti-B0 mixing is measured using the partially reconstructed semileptonic decay anti-B0 -> l- nubar D*+ X. The data sample was collected with the CDF detector at the Fermilab Tevatron collider during 1992 - 1995 by triggering on the existence of two lepton candidates in an event, and corresponds to about 110 pb-1 of pbar p collisions at sqrt(s) = 1.8 TeV. We estimate the proper decay time of the anti-B0 meson from the measured decay length and reconstructed momentum of the l- D*+ system. The charge of the lepton in the final state identifies the flavor of the anti-B0 meson at its decay. The second lepton in the event is used to infer the flavor of the anti-B0 meson at production. We measure the oscillation frequency to be Delta-md = 0.516 +/- 0.099 +0.029 -0.035 ps-1, where the first uncertainty is statistical and the second is systematic.Comment: 30 pages, 7 figures. Submitted to Physical Review

Weak pairwise correlations imply strongly correlated network states in a neural population

Biological networks have so many possible states that exhaustive sampling is impossible. Successful analysis thus depends on simplifying hypotheses, but experiments on many systems hint that complicated, higher order interactions among large groups of elements play an important role. In the vertebrate retina, we show that weak correlations between pairs of neurons coexist with strongly collective behavior in the responses of ten or more neurons. Surprisingly, we find that this collective behavior is described quantitatively by models that capture the observed pairwise correlations but assume no higher order interactions. These maximum entropy models are equivalent to Ising models, and predict that larger networks are completely dominated by correlation effects. This suggests that the neural code has associative or error-correcting properties, and we provide preliminary evidence for such behavior. As a first test for the generality of these ideas, we show that similar results are obtained from networks of cultured cortical neurons.Comment: Full account of work presented at the conference on Computational and Systems Neuroscience (COSYNE), 17-20 March 2005, in Salt Lake City, Utah (http://cosyne.org

Impact of a Tutored Theoretical-Practical Training to Develop Undergraduate Students’ Skills for the Detection of Caries Lesions: Study Protocol for a Multicenter Controlled Randomized Study

Background: Tutored laboratorial activities could be a manner of improving the competency development of students. However, its impact over conventional theoretical classes has not yet been tested. Additionally, different university contexts could influence this issue and should be explored. Objective: To assess the impact of a tutored theoretical-practical training for teaching undergraduate students to detect caries lesions as compared with theoretical teaching activities. The impact of these teaching/learning activities will be assessed in terms of efficacy, cost/benefit, retention of knowledge/acquired competences, and student acceptability. Methods: Sixteen centers (7 centers from Brazil and 9 centers from other countries throughout the world) are involved in the inclusion of subjects for this protocol. A randomized controlled study with parallel groups will be conducted. One group (control) will be exposed to a 60- to 90-minute conventional theoretical class and the other group (test) will be exposed to the same theoretical class and also a 90-minute laboratory class, including exercises and discussions based on the evaluation of a pool of images and extracted teeth. The mentioned outcomes will be evaluated immediately after the teaching activities and also in medium- and long-term analyses. To compare the long-term outcomes, students who enrolled in the university before the participating students will be interviewed for data collection and these data will be used as a control and compared with the trained group. This stage will be a nonrandomized phase of this study, nested in the main study. Appropriate statistical analysis will be performed according to the aims of this study. Variables related to the centers will also be analyzed and used to model adjustment as possible sources of variability among results. Results: This ongoing study is funded by a Brazilian national funding agency (CNPq- 400736/2014-4). We expect that the tutored theoretical-practical training will improve the undergraduate students’ performance in the detection of caries lesions and subsequent treatment decisions, mainly in terms of long-term retention of knowledge. Our hypothesis is that tutored theoretical-practical training is a more cost-effective option for teaching undergraduate students to detect caries lesions. Conclusions: If our hypothesis is confirmed, the use of laboratory training in conjunction with theoretical classes could be used as an educational strategy in Cariology to improve the development of undergraduate students’ skills in the detection of caries lesions and clinical decision-making

Three-Dimensional Acoustic Displays In A Museum Employing WFS (Wave Field Synthesis) And HOA (High Order Ambisonics)

The paper describes the sound systems and the listening rooms installed in the new "museum of reproduced sound", actually being built in Parma, restoring an ancient church. The museum is devoted to the exposition of a huge collection of antique radios and gramophones, but it will also exploit the frontiers of modern methods for immersive surround reproduction: WFS and HOA. In the main hall, a large planar WFS loudspeaker array is employed for inviting the visitors to enter the world of sound reproduction, providing stunning effects and emotional sounds enveloping them from many directions. At the end of the exposition path, a special HOA space is employed for showing the recent developments of recording/reproduction methods started from the Ambisonics concept, capable of creating natural reproduction of sport events, live music and other immersive acoustical experiences; in this room also a binaural/transaural system is available. A second, larger listening room capable of 30seats is equipped with a horizontal WFS array covering the complete perimeter of the room. The paper describes the technology employed, the problems encountered due to the difficult acoustical conditions (the museum was formerly a church), and the novel software tools developed for the purpose on LINUX platforms

Managing caries:the need to close the gap between the evidence base and current practice

Underpinned by a changing knowledge of the aetiology of caries and its sequelae, and assisted by established and advancing dental materials, there is growing evidence supporting less invasive management of dental caries based on the principles of minimal intervention dentistry. This narrative review assesses both the evidence and the adoption of less invasive caries management strategies and describes ways in which the gap between evidence and practice might be overcome. While there is increasing data supporting less invasive management of carious lesions, these are not standard in most dental practices worldwide. Usually, clinical studies focused on efficacy as outcome, and did not take into consideration the views and priorities of other stakeholders, such as primary care dentists, educators, patients and those financing services. Involving these stakeholders into study design and demonstrating the broader advantages of new management strategies might improve translation of research into practice. In theory, clinical dentists can rely on a growing evidence in cariology regarding less invasive management options. In practice, further factors seem to impede adoption of these strategies. Future research should address these factors by involving major stakeholders and investigating their prioritised outcomes to narrow or close the evidence gap.</p

CariesCare practice guide : consensus on evidence into practice

This CariesCare practice guide is derived from the International Caries Classification and Management System (ICCMS) and provides a structured update for dentists to help them deliver optimal caries care and outcomes for their patients. This '4D cycle' is a practice-building format, which both prevents and controls caries and can engage patients as long-term health partners with their practice. CariesCare International (CCI™) promotes a patient-centred, risk-based approach to caries management designed for dental practice. This comprises a health outcomes-focused system that aims to maintain oral health and preserve tooth structure in the long-term. It guides the dental team through a four-step process (4D system), leading to personalised interventions: 1st D: Determine Caries Risk; 2nd D: Detect lesions, stage their severity and assess their activity status; 3rd D: Decide on the most appropriate care plan for the specific patient at that time; and then, finally, 4th D: Do the preventive and tooth-preserving care which is needed (including risk-appropriate preventive care; control of initial non-cavitated lesions; and conservative restorative treatment of deep dentinal and cavitated caries lesions). CariesCare International has designed this practice-friendly consensus guide to summarise best practice as informed by the best available evidence. Following the guide should also increase patient satisfaction, involvement, wellbeing and value, by being less invasive and more health-focused. For the dentist it should also provide benefits at the professional and practice levels including improved medico-legal protection