765 research outputs found

    Endoscopy-assisted removal through combined lower and middle meatotomies of an ectopic upper third molar in the sinus associated with a dentigerous cyst

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    The aim of this case report is to present an original conservative technique for the transnasal endoscopy-assisted extraction of an ectopic upper third molar associated with a dentigerous cyst occupying the whole maxillary sinus by means of combined lower and middle meatotomies. The proposed technique is a viable, minimally-invasive alternative to the Caldwell–Luc operation (with or without the repositioning of a bone lid), and also to endoscopic middle meatal antrostomy in cases where this would be unable to ensure adequate access because of the position and size of the ectopic tooth and associated cyst

    Monitors that Learn from Failures: Pairing STL and Genetic Programming

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    In several domains, systems generate continuous streams of data during their execution, including meaningful telemetry information, that can be used to perform tasks like preemptive failure detection. Deep learning models have been exploited for these tasks with increasing success, but they hardly provide guarantees over their execution, a problem which is exacerbated by their lack of interpretability. In many critical contexts, formal methods, which ensure the correct behaviour of a system, are thus necessary. However, specifying in advance all the relevant properties and building a complete model of the system against which to check them is often out of reach in real-world scenarios. To overcome these limitations, we design a framework that resorts to monitoring, a lightweight runtime verification technique that does not require an explicit model specification, and pairs it with machine learning. Its goal is to automatically derive relevant properties, related to a bad behaviour of the considered system, encoded by means of formulas of Signal Temporal Logic (STL). Results based on experiments performed on well-known benchmark datasets show that the proposed framework is able to effectively anticipate critical system behaviours in an online setting, providing human-interpretable results

    School voucher Italian style

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    School vouchers introduced recently in some Italian regions have lowered the cost of private schools. On one side, we provide evidence that Italian private schools may be selected for different reasons than quality considerations. On the other side, by exploiting individual data on voucher applicants, we present evidence that the percentage of voucher applicants is higher the higher the average quality of private schools, which we explain with the fact that better quality schools provide better services to students, including information and consulting on vouchers. We show that enrolment in private schools responds sluggishly to changes in tuition induced by vouchers. Under stringent assumptions, we estimate the slopes of demand and supply of private education in the largest Italian region, Lombardy, during the first two years since implementation of a voucher scheme, and provide a quantitative assessment of the long \u2013 term impact of vouchers on tuition fees and enrolment in private schools

    Enzyme activity as an indicator of soil quality changes indegraded cultivated acrisols as the mexican trans-volcanic belt.

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    9 P.Soils located at the Mexican Trans-volcanic Belt (MTB) have a worrying degree of degradation due to inappropriate management practices. Early indicators of soil changes are very useful to alert about negative impacts of wrong managements on these volcanic soils. The aim of this work was to evaluate the short-term effects (4 years) of different agricultural practices on soil organic matter (SOM) quality and to validate the potential of the selected biochemical properties as optimal early indicators of soil quality in Mexican cultivated Acrisols. During 2002–2005 four agronomic management systems: conventional (Tc); improved conventional (Ti); organic (To) and fallow (Tf) were assayed in plots located at the MTB. An uncultivated soil under grass cover (Sg) was used as reference. Soil samples were collected at 0–10 cm depth and were analysed chemically (soil organic C, total N, water-soluble C and humic C), and biochemically (total and extra-cellular enzyme activity). After 4 years, soil organic C, total N, water-soluble C and dehydrogenase activity had higher values in To, followed by Ti treatment. A similar response pattern was observed in the extra-cellular enzyme activity. The highest total enzyme activity was found in Sg, followed by Ti and To treatments, and the lowest values appeared in Tc and Tf. To and Ti increased SOM contents of the degraded Acrisols studied, while Tc and Tf managements decreased the quality of these soils. The results showed that the assayed soil enzymes can be used as indicators of quality changes of these Mexican volcanic soils.The authors thank the European Union for supporting the REVOLSO Project (INCO-DEV Program) and the Spanish Ministry of Education & Science. Thanks are also due to C. I. Hidalgo (Colegio de Postgraduados de Montecillo, Mexico) for the mineralogical identification of soil clays analysis and J. Padilla (Colegio de Postgraduados de Montecillo, Mexico), C. Macci, S. Doni and laboratory technicians from the Istituto per lo Studio degli Ecosistemi (CNR, Italy) for theirs lab assistance.Peer reviewe

    The impact of bioceramic scaffolds on bone regeneration in preclinical in vivo studies: A systematic review

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    Bioceramic scaffolds are appealing for alveolar bone regeneration, because they are emerging as promising alternatives to autogenous and heterogenous bone grafts. The aim of this systematic review is to answer to the focal question: in critical-sized bone defects in experimental animal models, does the use of a bioceramic scaffolds improve new bone formation, compared with leaving the empty defect without grafting materials or using autogenous bone or deproteinized bovine-derived bone substitutes? Electronic databases were searched using specific search terms. A hand search was also undertaken. Only randomized and controlled studies in the English language, published in peer-reviewed journals between 2013 and 2018, using critical-sized bone defect models in non-medically compromised animals, were considered. Risk of bias assessment was performed using the SYRCLE tool. A meta-analysis was planned to synthesize the evidence, if possible. Thirteen studies reporting on small animal models (six studies on rats and seven on rabbits) were included. The calvarial bone defect was the most common experimental site. The empty defect was used as the only control in all studies except one. In all studies the bioceramic materials demonstrated a trend for better outcomes compared to an empty control. Due to heterogeneity in protocols and outcomes among the included studies, no meta-analysis could be performed. Bioceramics can be considered promising grafting materials, though further evidence is needed

    Squeezing of electromagnetic field in a cavity by electrons in Trojan states

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    The notion of the Trojan state of a Rydberg electron, introduced by I.Bialynicki-Birula, M.Kali\'nski, and J.H.Eberly (Phys. Rev. Lett. 73, 1777 (1994)) is extended to the case of the electromagnetic field quantized in acavity. The shape of the electronic wave packet describing the Trojan state is practically the same as in the previously studied externally driven system. The fluctuations of the quantized electromagnetic field around its classical value exhibit strong squeezing. The emergence of Trojan states in the cylindrically symmetrical system is attributed to spontaneous symmetry braking.Comment: 9 pages, 8 figure

    How to measure the Bogoliubov quasiparticle amplitudes in a trapped condensate

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    We propose an experiment, based on two consecutive Bragg pulses, to measure the momentum distribution of quasiparticle excitations in a trapped Bose gas at low temperature. With the first pulse one generates a bunch of excitations carrying momentum qq, whose Doppler line is measured by the second pulse. We show that this experiment can provide direct access to the amplitudes uqu_{q} and vqv_{q} characterizing the Bogoliubov transformations from particles to quasiparticles. We simulate the behavior of the nonuniform gas by numerically solving the time dependent Gross-Pitaevskii equation.Comment: 12 pages, 4 figures include

    Experimental observation of the Bogoliubov transformation for a Bose-Einstein condensed gas

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    Phonons with wavevector q/â„Źq/\hbar were optically imprinted into a Bose-Einstein condensate. Their momentum distribution was analyzed using Bragg spectroscopy with a high momentum transfer. The wavefunction of the phonons was shown to be a superposition of +q and -q free particle momentum states, in agreement with the Bogoliubov quasiparticle picture.Comment: 4 pages, 3 figures, please take postscript version for the best version of Fig

    Constraint degree in revision total knee replacement: a registry study on 1432 patients

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    Purpose: Total knee replacement (TKR) failure represents a hard challenge for knee surgeons. TKR failure can be managed in revision with different constraint, related with soft and bone knee damages. The choice of the right constraint for every failure cause represents a not summarized entity. The purpose of this study is identifying distribution of different constraints in revision TKR (rTKR) for failure cause and the overall survival. Methods: A registry study based on the Emilia Romagna Register of the Orthopaedic Prosthetic Implants (called RIPO) was performed with a selection of 1432 implants, in the period between 2000 and 2019. Selection implants including primary surgery constraint, failure cause and constraint revision for every patient, and divided for constraint degrees used during procedures (Cruciate Retaining-CR, Posterior Stabilized-PS, Condylar Constrained Knee-CCK, Hinged). Results: The most common cause of primary TKR failure was aseptic loosening (51,45%), followed by septic loosening (29,12%). Each type of failure was managed with different constraint, the most used was CCK in the most of failure causes, such as to manage aseptic and septic loosening in CR and PS failure. Overall survival of TKA revisions has been calculated at 5 and 10 years for each constraint, with a range of 75.1-90.0% at 5 years and 75.1-87.5% at 10 years. Conclusion: Constraint degree in rTKR is typically higher than primary, CCK is the most used constraint in revision surgery with an overall survival of 87.5% at 10 years
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