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1.
Phys Rev Lett ; 132(15): 151001, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682982

RESUMO

We report on a measurement of astrophysical tau neutrinos with 9.7 yr of IceCube data. Using convolutional neural networks trained on images derived from simulated events, seven candidate ν_{τ} events were found with visible energies ranging from roughly 20 TeV to 1 PeV and a median expected parent ν_{τ} energy of about 200 TeV. Considering backgrounds from astrophysical and atmospheric neutrinos, and muons from π^{±}/K^{±} decays in atmospheric air showers, we obtain a total estimated background of about 0.5 events, dominated by non-ν_{τ} astrophysical neutrinos. Thus, we rule out the absence of astrophysical ν_{τ} at the 5σ level. The measured astrophysical ν_{τ} flux is consistent with expectations based on previously published IceCube astrophysical neutrino flux measurements and neutrino oscillations.

2.
J Oral Rehabil ; 51(4): 712-723, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38087990

RESUMO

BACKGROUND: Tooth wear is a multifactorial condition that manifests through various signs and symptoms. These individual signs and symptoms were described in multiple studies, leading to the inclusion in TWES 2.0 (Tooth Wear Evaluation System 2.0) and the forthcoming DC-TW (Diagnostic Criteria for Tooth Wear). However, a study evaluating their reliability has yet to be conducted. OBJECTIVE: The aim of the study was to examine the reliability in the assessment of 6 signs of pathological tooth wear and 18 clinical signs and symptoms determining aetiology, all of which are included in the TWES 2.0/DC-TW. METHODS: 48 dental students (operators) evaluated patient cases from a patient pool of 14 patients on dental casts and high-resolution intraoral photographs. The agreement between all operators for each sign and symptom was calculated based on ICC (Intraclass Correlation Coefficients). Additionally, the agreement of each operator's evaluation with a predefined sample solution was calculated based on Cohen's kappa. RESULTS: Inter-user agreement ranged from near perfect (0.91) to poor (0.02) for the various pathology signs or aetiology symptoms of tooth wear (mean 0.32). The agreements of the operator's ratings compared to the sample solution resulted in Cohen's kappa from 0.18 to 1 (mean 0.59) for the pathology signs and ranged from 0.02 to 0.51 for the aetiology signs (mean 0.38). CONCLUSIONS: The reliability of the signs and symptoms examined and the ability of individual investigators to correctly identify and assign signs and symptoms varied widely. The current assessment tools for the qualification of tooth wear need further refinement, and examiners need intensive training in tooth wear assessment.


Assuntos
Dente Molar , Desgaste dos Dentes , Humanos , Reprodutibilidade dos Testes , Desgaste dos Dentes/diagnóstico
3.
J Prosthodont Res ; 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37853627

RESUMO

PURPOSE: To investigate whether depth-gauge burs in veneer preparations influence preparation depth in a randomized, controlled, single-blinded trial and whether inexperienced operators can perform adequate veneer preparations. METHODS: Participants were 20 undergraduate dental students with no prior veneer preparation experience. The instruments used were the "Laminate Veneer System" (LVS), "Keramik-Veneers. de" (KVD), and a "Freehand" group (FH) for reference. All participants prepared three educational acrylic resin maxillae and three mandibular central incisors mounted in typodonts in patient simulators. The objectives were to achieve a preparation depth of 0.6 mm (tooth 11) and 0.4 mm (tooth 31). The sequences of the instruments used and prepared teeth were randomized. The measurements were performed using a laser triangulation coordinate-measuring machine. The data were stratified according to tooth location. RESULTS: The preparation depths of both depth-gauge-instrument-groups LVS and KVD achieved the objectives significantly better than did the instruments from the "Freehand" group (P < 0.001). The differences between the depth gauge groups were insignificant, although the maximum preparation depths were smaller in the KVD group. Regarding the prepared teeth, the preparation depths in the mandibular incisors were lower, and the differences were smaller. CONCLUSIONS: The use of special depth-gauge burs for initial veneer preparation leads to significantly lower preparation depths than "Freehand" preparations. The tapered instruments resulted in a lower incidence of extreme preparation depths. The inexperienced operators performed veneer preparation remarkably well.

4.
J Clin Med ; 12(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37568349

RESUMO

Idiopathic condylar resorption (ICR), though a rare event, is associated with severe detrimental sequelae for the patient. To date, the etiology remains unknown, and treatment strategies are highly controversial. Therefore, the aim of this study is to present an analysis of the consensus- and evidence-based approach to ICR by a German interdisciplinary guideline project of the AWMF (Association of the Scientific Medical Societies in Germany). Following a systematic literature search, including 56 (out of an initial 97) publications, with a predominantly low level of evidence (LoE), two independent working groups (oral and maxillofacial surgery and interdisciplinary, respectively) voted on a draft comprising 25 recommendations in a standardized anonymized and blinded Delphi procedure. While the results of the votes were relatively homogeneous, the interdisciplinary phase required a significantly higher number of rounds (p < 0.001). Most of the controversial recommendations were related to initial imaging (with consensus on CT/CBCT as the current diagnostic standard for imaging), pharmacotherapy (no recommendation due to lack of evidence), discopexy (no recommendation possible due to low LoE) and timing of orthognathic surgery (with consensus on two-staged procedures after invasive TMJ surgery, except for single-stage procedures if combined with total joint reconstruction). Overall, the Delphi procedure resulted in an interdisciplinary guideline offering the best possible evidence- and consensus-based expertise to date in the diagnosis and treatment of ICR.

5.
Sci Rep ; 13(1): 11721, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474563

RESUMO

The present study investigated to what extent a systematic evaluation of electronic condylar motion recordings leads to reproducible results in different examiners. The study was based on the anonymized condylar motion recordings of 20 patients (Cadiax compact II system). These were recruited consecutively from the examinations in a center specializing in diagnosing and managing temporomandibular disorders (TMD). Four trained practitioners independently evaluated the identical movement recordings of all patients after calibration. The evaluation was based on the previously published evaluation system. The results were recorded digitally in a database. The findings were then compared, and the matching values were determined (Fleiss' Kappa). The evaluation, according to Fleiss' Kappa, showed that the consistency of the assessment of the findings among the examiners is excellent (mean value 0.88, p < 0.00001). The study shows that calibrated dentists achieved reproducible results using this evaluation system and computer-assisted reporting. Good reproducibility confirms the reliability of systematic evaluation of clinical motion analysis. The ambiguities uncovered and eliminated in the study should avoid misunderstandings in the future. Both factors establish the prerequisites for applying condylar motion analysis in clinical practice.


Assuntos
Côndilo Mandibular , Transtornos da Articulação Temporomandibular , Humanos , Reprodutibilidade dos Testes , Transtornos da Articulação Temporomandibular/diagnóstico , Movimento , Computadores , Articulação Temporomandibular
6.
Science ; 380(6652): 1338-1343, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37384687

RESUMO

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

7.
Science ; 378(6619): 538-543, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36378962

RESUMO

A supermassive black hole, obscured by cosmic dust, powers the nearby active galaxy NGC 1068. Neutrinos, which rarely interact with matter, could provide information on the galaxy's active core. We searched for neutrino emission from astrophysical objects using data recorded with the IceCube neutrino detector between 2011 and 2020. The positions of 110 known gamma-ray sources were individually searched for neutrino detections above atmospheric and cosmic backgrounds. We found that NGC 1068 has an excess of [Formula: see text] neutrinos at tera-electron volt energies, with a global significance of 4.2σ, which we interpret as associated with the active galaxy. The flux of high-energy neutrinos that we measured from NGC 1068 is more than an order of magnitude higher than the upper limit on emissions of tera-electron volt gamma rays from this source.

8.
Phys Rev Lett ; 129(15): 151801, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36269964

RESUMO

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{µ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9} eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

9.
Phys Rev Lett ; 129(1): 011804, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35841552

RESUMO

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{µτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{µτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

10.
Phys Rev Lett ; 128(5): 051101, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35179913

RESUMO

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19} cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with ß≳0.8 and up to ß∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

11.
J Oral Rehabil ; 49(1): 81-91, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34719055

RESUMO

BACKGROUND: Tooth wear is a multifactorial process, leading to the loss of dental hard tissues. Therefore, it is important to detect the level of tooth wear at an early stage, so monitoring can be initiated. The Tooth Wear Evaluation System (TWES) enables such a multistage diagnosis of tooth wear. The further developed TWES 2.0 contains a complete taxonomy of tooth wear, but its reliability has not yet been validated. OBJECTIVES: The aim of the study was to examine in a randomised controlled trial (RCT) whether diagnoses made based on the TWES 2.0 are reproducible and whether this reproducibility is also achieved with computer-assisted diagnostics. METHODS: 44 dental students received extensive training in TWES 2.0 assessment and taxonomy. The students each evaluated at least 10 (of the present 14) anonymised patient cases using gypsum models and high-resolution intra-oral photographs according to TWES 2.0. One half initially evaluated on paper; the other half used dedicated software (CMDfact / CMDbrux). After half of the patient cases (5), the evaluation methods were switched (AB/BA crossover design). The diagnoses were then evaluated for agreement with the predefined sample solution. RESULTS: Evaluation of agreement with the sample solution according to Cohen's kappa indicated a value of 0.46 for manual (traditional) evaluation; and 0.44 for computer-assisted evaluation. Evaluation of agreement between examiners was 0.38 for manual and 0.48 for computer-assisted evaluation (Fleiss' kappa). CONCLUSION: The results of this study proved that the taxonomy of the TWES 2.0 has acceptable reliability and can thus be used by dentists. Accordingly, the system can be learned quickly even by untrained practitioners. Comparable results are achieved with computer-assisted evaluation.


Assuntos
Atrito Dentário , Erosão Dentária , Desgaste dos Dentes , Computadores , Estudos Cross-Over , Humanos , Reprodutibilidade dos Testes , Erosão Dentária/diagnóstico , Desgaste dos Dentes/diagnóstico
12.
Phys Rev Lett ; 125(14): 141801, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064514

RESUMO

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100 eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5 eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

13.
Phys Rev Lett ; 125(12): 121104, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016752

RESUMO

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of ϕ_{astro}=1.66_{-0.27}^{+0.25} at E_{0}=100 TeV, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices γ≤2.28 at ≥3σ significance level. Because of high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below ∼100 TeV compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p value ≥0.06). The sizable and smooth flux measured below ∼100 TeV remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi Large Area Telescope, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma rays.

15.
J Oral Rehabil ; 47(6): 703-712, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32274827

RESUMO

BACKGROUND: Tooth wear is a multifactorial condition, leading to the loss of dental hard tissues. Physiological tooth wear is a slow process that normally does not lead to any subjective symptoms. When the condition progresses, it can become pathological, and several signs and symptoms may occur. The Tooth Wear Evaluation System (TWES) was described to implement a systematic diagnostic and management approach. Recently, management guidelines were presented in a European Consensus Statement (ECS) as well. OBJECTIVES: To evaluate the TWES in practice and to integrate the principles described in the ECS in order to compose a renewed TWES 2.0 and a new taxonomy. METHODS: The TWES and the recommendations of the ECS were used by dental clinicians, in order to test its applicability in practice. RESULTS: Agreement was reached that the TWES 2.0 will use a stepwise approach, with a straightforward Tooth Wear Screening part and a more detailed Tooth Wear Status part. Also, the assessment of pathology from the ECS is incorporated in the TWES 2.0 (both classification and taxonomy). CONCLUSIONS: In the TWES 2.0 is described that tooth wear is pathological if moderate/severe/extreme tooth wear is present, in combination with one or several described signs and symptoms. Aetiology can be assessed by findings that indicate a chemical and/or a mechanical cause. The taxonomy may help to identify situations in which preventive (restorative) interventions in early stages of tooth wear can be indicated. The reliability and validity of the adapted parts must be proven.


Assuntos
Atrito Dentário , Desgaste dos Dentes , Consenso , Humanos , Programas de Rastreamento , Reprodutibilidade dos Testes
16.
J Oral Rehabil ; 47(5): 651-658, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32080883

RESUMO

BACKGROUND: The diagnosis and management of patients suffering from occlusal dysesthesia (OD) remain a major challenge for dental practitioners and affected patients. OBJECTIVES: To present the results of a literature-based expert consensus intended to promote better understanding of OD and to facilitate the identification and management of affected patients. METHODS: In 2018, electronic literature searches were carried out in PubMed, Cochrane Library and Google Scholar as well as in the archives of relevant journals not listed in these databases. This approach was complemented by a careful assessment of the reference lists of the identified relevant papers. The articles were weighted by evidence level, followed by an evaluation of their contents and a discussion. The result represents an expert consensus. RESULTS: Based on the contents of the 77 articles identified in the search, the current knowledge about clinical characteristics, epidemiology, aetiology, diagnostic process, differential diagnosis and management of OD is summarised. CONCLUSIONS: Occlusal dysesthesia exists independently of the occlusion. Instead, it is the result of maladaptive signal processing. The focus should be on patient education, counselling, defocusing, cognitive behavioural therapy, supportive drug therapy and certain non-specific measures. Irreversible, specifically an exclusively dental treatment approach must be avoided.


Assuntos
Má Oclusão , Parestesia , Oclusão Dentária , Odontólogos , Humanos , Papel Profissional
17.
Phys Rev Lett ; 124(5): 051103, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32083934

RESUMO

This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1 TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

18.
J Oral Rehabil ; 47(2): 164-169, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31430389

RESUMO

As yet, there are still no evidence-based clinical diagnostic and management guidelines for ambulatory single-channel EMG devices, like the BUTLER® GrindCare® (GrindCare), that are used in patients with sleep bruxism. Therefore, a consensus meeting was organised with GrindCare developers, researchers, and academic and non-academic clinicians experienced with the use of ambulatory EMG devices. The aim of the meeting was to discuss and develop recommendations for clinical guidelines for GrindCare usage, based on the existing clinical and research experience of the consensus meeting's participants. As an important outcome of the consensus meeting, clinical guidelines were proposed in which an initial 2-week baseline phase with the device in its inactive (non-stimulus) mode for habituation and assessment of the number of jaw-muscle activities is followed by a 4-week active phase with contingent electrical stimuli suppressing the jaw-muscle activities. As to avoid the commonly reported reduction in sensitivity to the stimuli, a 2-week inactive phase is subsequently installed, followed by a repetition of active and inactive phases until a lasting reduction in the number of jaw-muscle activities and/or associated complaints has been achieved. This proposal has the characteristics of a single-patient clinical trial. From a research point of view, adoption of this approach by large numbers of GrindCare users creates a great opportunity to recruit relatively large numbers of study participants that follow the same protocol.


Assuntos
Bruxismo , Terapia por Estimulação Elétrica , Bruxismo do Sono , Consenso , Estimulação Elétrica , Eletromiografia , Humanos
19.
Br Dent J ; 226(10): 739-748, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31127218

RESUMO

The introduction of adhesive techniques in combination with translucent restorative materials has greatly influenced treatment concepts in fixed prosthodontics. Modern production technologies offer access to new polymer materials that provide innovative pre-treatment options for complex prosthetic rehabilitations. Additionally, computer-aided design and manufacturing (CAD/CAM) provides access to new ceramic types and thus extends the range of indications for metal-free restorative options. With these developments, important changes of treatment concepts in fixed prosthodontics have occurred which affect the professional life of dental practitioners with a focus on prosthetic dentistry. This article gives an overview of the advances in selected fields of fixed prosthodontics and provides support in material selection for different kinds of indications, from single-tooth restorations to fixed dental prostheses.


Assuntos
Planejamento de Prótese Dentária , Prostodontia , Cerâmica , Desenho Assistido por Computador , Materiais Dentários , Humanos
20.
Phys Rev Lett ; 122(5): 051102, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-30822017

RESUMO

High-energy neutrino emission has been predicted for several short-lived astrophysical transients including gamma-ray bursts (GRBs), core-collapse supernovae with choked jets, and neutron star mergers. IceCube's optical and x-ray follow-up program searches for such transient sources by looking for two or more muon neutrino candidates in directional coincidence and arriving within 100 s. The measured rate of neutrino alerts is consistent with the expected rate of chance coincidences of atmospheric background events and no likely electromagnetic counterparts have been identified in Swift follow-up observations. Here, we calculate generic bounds on the neutrino flux of short-lived transient sources. Assuming an E^{-2.5} neutrino spectrum, we find that the neutrino flux of rare sources, like long gamma-ray bursts, is constrained to <5% of the detected astrophysical flux and the energy released in neutrinos (100 GeV to 10 PeV) by a median bright GRB-like source is <10^{52.5} erg. For a harder E^{-2.13} neutrino spectrum up to 30% of the flux could be produced by GRBs and the allowed median source energy is <10^{52} erg. A hypothetical population of transient sources has to be more common than 10^{-5} Mpc^{-3} yr^{-1} (5×10^{-8} Mpc^{-3} yr^{-1} for the E^{-2.13} spectrum) to account for the complete astrophysical neutrino flux.

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