566 research outputs found

    Perceived room size and source distance in five simulated concert auditoria

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    Room impulse responses (stereophonic and binaural) were recorded using identical procedures in five concert auditoria: the large, medium and small halls of Rome's Parco della Musica, Parma's Auditorium Paganini, and Kirishima's Miyama Conseru. A subjective test was conducted, using an anechoic recording of a piano accordion convolved with these impulse responses, and reproduced over four audio systems (binaural headphones, conventional stereophony, stereo dipole and double stereo dipole). The frequency responses of these playback systems were matched, and the playback level was realistic for the instrument and auditoria. Results indicate that the audio system can significantly affect distance estimation and realism judgments (with a non-significant effect on room size ratings). The situation (auditorium and seat position) significantly affects distance estimations and room size ratings (but not realism ratings). Room acoustical parameters were determined from for each situation, and relationships between these and the auditory distance and room size judgments were investigated. Auditory distance perception is primarily correlated (negatively) to the reproduced sound pressure level. Results for perceived room size are more complex, and demand further research for interpretation. Results tentatively indicate that among these non-individualized two-channel systems, the single stereo dipole system provides a plausible reproduction of the auditorium acoustical environment for the purpose of subjective assessment

    Scattering Uniformity Measurements and First Reflection Analysis in a Large Nonanechoic Environment

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    Following previous investigation, carried out at the University of Parma in 1999 and 2000, LAE (Laboratory of Acoustics and Electroacoustics) started a new measurement campaign to compare with the original results on the same type of diffusor panels, to verify AES-4id-2001 measurement standard and to investigate the nature of scattering phenomena in more detail. Measurements are conducted on the floor of a large closed space to obtain a reflection free time window, long enough to study the first reflection from the panel; the use of sine sweep excitation signals instead of the recommended MLS ones permits to ameliorate the acquisition process. The present article discusses research background studies and the results from the first round of measurements

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

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    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

    Network information and connected correlations

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    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 NN--point correlation is measured by a decrease in entropy for the joint distribution of NN variables relative to the maximum entropy allowed by all the observed N1N-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

    In vitro Validation of Quantitative Light-Induced Fluorescence for the Diagnosis of Enamel Fluorosis in Permanent Teeth

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    This study aimed to validate quantitative light-induced fluorescence (QLF) as a diagnostic tool for mild and moderate enamel fluorosis in permanent teeth, comparing it to visual diagnosis and histological assessment completed using polarized light microscopy (PLM). The buccal surfaces of 139 teeth were visually classified using the Thylstrup and Fejerskov Index (TFI) into sound (TFI 0; n = 17), mild (TFI 1-2; n = 69), and moderate (TFI 3-4; n = 43) fluorosis. Fluorosis was then assessed with QLF (variables ΔF, A, and ΔQ at 5-, 15-, and 30-radiance thresholds) using as reference areas the entire surface and a region of interest (ROI), identified as the most representative region of a fluorosis lesion. PLM images of longitudinal thin sections including the ROI were assessed for histological changes. Correlations among TFI, PLM, and QLF were determined. A receiver-operating characteristic curve was conducted to determine QLF's diagnostic accuracy when compared to the TFI and PLM assessments. This was used to assess the probability that the images were correctly ranked according to severity as determined by PLM and TFI. A positive correlation was found between QLF and PLM, and between QLF and TFI. QLF showed the highest sensitivity and specificity for the diagnosis of mild fluorosis. There was also a strong agreement between TFI and PLM. The selection of a ROI resulted in a stronger correlation with TFI and PLM than when the entire surface was used. The study results indicate that defining an ROI for QLF assessments is a valid method for the diagnosis of mild and moderate enamel fluorosis

    Update of Laparoscopic Surgery in Borderline Ovarian Tumor: Systematic Review

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    Background: Borderline ovarian tumor (BOT) predominantly affects young women and is often diagnosed at an early stage. BOT accounts for 15% of all epithelial tumors. In this regard, a minimally invasive surgical approach and the ability to preserve fertility, without increasing the incidence of recurrences or worsening the prognosis, are crucial. This review aims to provide an update on the role and indications of laparoscopic surgery in BOTs. Methods: The electronic research was performed on Pubmed, Medline, and Embase. Articles published in the last 20 years (2004–2023) were included, and the following keywords were used: ‘borderline ovarian tumor’ and ‘laparoscopic surgery’, ‘borderline ovarian tumor’ and ‘minimally invasive surgery’, ‘borderline ovarian tumor’ and ‘fertility sparing’, ‘borderline ovarian tumor’ and ‘recurrence’ and ‘Borderline ovarian tumor’ and ‘relapse’. The agreement about potential relevance was reached by consensus of the researchers and according to PRISMA statement guidelines. We thoroughly reviewed all bibliographies to assess the inclusion of any further eligible studies. We excluded studies that did not align with the study’s objectives. Results: The electronic database search yielded 767 total studies. Of whom, 188 were published before 2004, 84 were case reports, and 45 were not in the English language. Of the remaining 450 studies, 148 were considered eligible for the study. We included 20 studies in this review. Conclusions: Despite the latest guidelines recommending an open approach for the treatment of BOT, the laparoscopic approach has gained popularity as a feasible and safe alternative. The use of an endo-bag, along with advanced laparoscopic skills, has made the minimally invasive approach increasingly safe, with oncological outcomes almost comparable to those of reference. Moreover, in the context of fertility-sparing surgery (FSS), laparoscopy seems to be associated with improved obstetrical outcomes, without detrimental effects on overall survival and disease-free survival. Therefore, the laparoscopic approach in the treatment of BOT appears to be a safe and effective option, especially in the case of FSS

    CariesCare practice guide : consensus on evidence into practice

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    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

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

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    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

    Non-invasive study of natural dyes on historical textiles from the collection of Michelangelo Guggenheim

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    A selection of historical textile fragments from the Venetian art dealer Moisè Michelangelo Guggenheim collection, ranging from XV to XVIII century, has been investigated by means of non-invasive techniques in order to reveal the coloring materials. Imaging was preliminarily used to visually investigate the selected artwork fragments in order to investigate their structure and conservation conditions; Fiber Optics Reflectance Spectroscopy (FORS) allowed recognizing the main natural dyestuffs, such as indigotin and anthraquinones-based compounds, except the yellow ones, difficultly identifiable when using this non-invasive technique. Collected spectroscopic data have been also elaborated by using a clustering algorithm that permitted to group collected spectra on the basis of similar properties and evidencing their inflection point wavelength as the most influencing feature

    Search for Narrow Diphoton Resonances and for gamma-gamma+W/Z Signatures in p\bar p Collisions at sqrt(s)=1.8 TeV

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    We present results of searches for diphoton resonances produced both inclusively and also in association with a vector boson (W or Z) using 100 pb^{-1} of p\bar p collisions using the CDF detector. We set upper limits on the product of cross section times branching ratio for both p\bar p\to\gamma\gamma + X and p\bar p\to\gamma\gamma + W/Z. Comparing the inclusive production to the expectations from heavy sgoldstinos we derive limits on the supersymmetry-breaking scale sqrt{F} in the TeV range, depending on the sgoldstino mass and the choice of other parameters. Also, using a NLO prediction for the associated production of a Higgs boson with a W or Z boson, we set an upper limit on the branching ratio for H\to\gamma\gamma. Finally, we set a lower limit on the mass of a `bosophilic' Higgs boson (e.g. one which couples only to \gamma, W, and Z$ bosons with standard model couplings) of 82 GeV/c^2 at 95% confidence level.Comment: 30 pages, 11 figure
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