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1.
Orthod Fr ; 91(1-2): 101-114, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33146125

RESUMO

We could study Cone Beam documents of patients consulting in ORL with standard Angle Class I occlusion (45 ND), patients consulting in orthodontics with an orthodontic Class II (51 APNS) and patients with a surgical Class II (83 APS). The used 3D biometry calculates systematically a 164 set of parameters able to take into account all kinds of disharmonies; among which 38 parameters are specifically devoted to anterior-posterior "off asymmetry" pathologies. Then the specific Artificial Intelligence (AI) programs treat morphological data and give textual diagnoses. Analysis of the global sample aims to control the efficiency, separating different sub-samples one each other: t test appreciates efficiency of each parameter to recognize clinical sub-sample. The correlation coefficient, r, between each parameter and pseudo Angle molars Class II (GMMy-Gmmy) give the importance of its tie with Class II pathology. Presentation of parameters medium values in each sub-group gives the medium profiles. By direct comparison of patient's parameters values with medium profile, it is possible to locate patient's pathology. So we can take in account new parameters like arches upper/lower gap, anterior bases upper/lower gap, compensatingparameters... It is then possible to make more secure the clinical decision.


Assuntos
Inteligência Artificial , Má Oclusão de Angle Classe II , Biometria , Cefalometria , Humanos , Má Oclusão de Angle Classe II/diagnóstico por imagem , Má Oclusão de Angle Classe II/terapia , Crânio
2.
Orthod Fr ; 91(1-2): 115-128, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33146126

RESUMO

With the conventional 2D exam of clinical cases, the diagnosis is penalized by the lack of data, not only for vertical or transverse or asymmetrical problems, but for classical cases of anteroposterior dysharmonies. In these cases, the effectively used parameter, ANB angle, seems insufficient. So the authors elaborated a 3D biometry tool. The program of morphological analysis is able to deliver a complete description of dysharmony, supported by Cone Beam data capture. In the first part of this article the authors present the foundation of the model: anatomical reference, skeletal landmarks, teeth location by inertia matrix calculus, parameters, diagnosis and aid to treatment plan. The second part is the presentation, step by step, of the program in function, analyzing a great case of Class II hyperdivergent, border line surgery. All along the diagnosis way, the authors make the assistant discover all the documents given by the computer about complete 3D diagnosis and aid to treatment plan.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Má Oclusão de Angle Classe II , Biometria , Cefalometria , Face/cirurgia , Humanos , Imageamento Tridimensional , Mandíbula
3.
Stud Health Technol Inform ; 275: 137-141, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33227756

RESUMO

Biostatistics and machine learning have been the cornerstone of a variety of recent developments in medicine. In order to gather large enough datasets, it is often necessary to set up multi-centric studies; yet, centralization of measurements can be difficult, either for practical, legal or ethical reasons. As an alternative, federated learning enables leveraging multiple centers' data without actually collating them. While existing works generally require a center to act as a leader and coordinate computations, we propose a fully decentralized framework where each center plays the same role. In this paper, we apply this framework to logistic regression, including confidence intervals computation. We test our algorithm on two distinct clinical datasets split among different centers, and show that it matches results from the centralized framework. In addition, we discuss possible privacy leaks and potential protection mechanisms, paving the way towards further research.


Assuntos
Bioestatística , Privacidade , Algoritmos , Biometria , Aprendizado de Máquina
4.
Artigo em Inglês | MEDLINE | ID: mdl-33017937

RESUMO

There is evidence to suggest that changes in kinematics and neuromuscular control in activities that take place over long periods of time lead to increased injury risk. The collection of biometric data over long time periods could provide insight into these injuries. However, it is difficult to analyse long period biometric data for occupations as the analysis depends on the activity being performed, and it is not practical to manually label the amount of data required. A sufficiently accurate human activity recognition algorithm can provide a means to segment the activities and allow this analysis, but the classification must be robust to the inter-individual differences, as well as the intra-individual variations in movement over time that are the target of analysis. This work presents a person-independent human activity recognition algorithm for sheep shearing using a Hidden Markov Model with physical features that are identified to be relevant to spinal movement quality. The classifier achieved an F1 score of 96.47% in identifying the shearing task.


Assuntos
Biometria , Análise de Dados , Algoritmos , Animais , Atividades Humanas , Humanos , Movimento , Ovinos
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1980-1983, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018391

RESUMO

Symmetry can be defined as uniformity, equivalence or exact similarity of two parts divided along an axis. While our left and right eyes clearly have a high degree of external bilateral symmetry, it is less obvious to what degree they have internal bilateral symmetry. In this paper, we try to find approximate-bilateral symmetry in retina, one of the internal parts of our eye, which plays a vital role in our vision and also can be used as a powerful biometric. Contrary to previous works, we study interretinal symmetry from a biometric perspective. In other words, we study whether the left and right retinal symmetry is strong enough to reliably tell whether a pair of the left and right retinas belongs to a single person. For this, we focus on overall symmetry of the retinas rather than specific attributes such as length, area, thickness, or the number of blood vessels. We evaluate and analyse the performance of both human and neural network based bilateral retina verification on fundus photographs. By experimenting on a publicly available data set, we confirm interretinal symmetry.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Fotografação , Biometria , Humanos , Procedimentos Cirúrgicos Oftalmológicos , Retina/diagnóstico por imagem
6.
An Acad Bras Cienc ; 92(3): e20180777, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111814

RESUMO

The transmuted family of distributions has been receiving increased attention over the last few years. In this paper, we generalize the Marshall-Olkin extended Lomax distribution using the quadratic rank transmutation map to obtain the transmuted Marshall-Olkin extended Lomax distribution. Several properties of the new distribution are discussed including the hazard rate function, ordinary and incomplete moments, characteristic function and order statistics. We provide an estimation procedure by the maximum likelihood method and a simulation study to assess the performance of the new distribution. We prove empirically the flexibility of the new model by means of an application to a real data set. It is superior to other three and four parameter lifetime distributions.


Assuntos
Biometria , Modelos Estatísticos , Probabilidade
7.
Zootaxa ; 4816(3): zootaxa.4816.3.12, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-33055700

RESUMO

Geometric morphometrics (GM) is a powerful analytical approach for evaluating phenotypic variation relevant to taxonomy and systematics, and as with any statistical methodology, requires adherence to fundamental assumptions for inferences to be strictly valid. An important consideration for GM is how landmark configurations, which represent sets of anatomical loci for evaluating shape variation through Cartesian coordinates, relate to underlying homology (Zelditch et al. 1995; Polly 2008). Perhaps more so than with traditional morphometrics, anatomical homology is a crucial assumption for GM because of the mathematical and biological interpretations associated with shape change depicted by deformation grids, such as the thin plate spline (Klingenberg 2008; Zelditch et al. 2012). GM approaches are often used to analyze shapes or outlines of structures, which are not necessarily related to common ancestry, and in this respect GM approaches that use linear semi-landmarks and related methods are particularly amenable to evaluating primary homology, or raw similarity between structures (De Pinna 1991; Palci Lee 2019). This relaxed interpretation of homology that focuses more on recognizable and repeatable landmarks is defensible so long as authors are clear regarding the purpose of the analyses and in defining their landmark configurations (Palci Lee 2019). Secondary homology, or similarity due to common ancestry, can also be represented with GM methods and is often assumed to be reflected in fixed Type 1 (juxtaposition of tissues) or Type 2 (self-evident geometry) landmarks (Bookstein 1991).


Assuntos
Biometria , Répteis , Animais , Matemática
8.
Indian J Dent Res ; 31(4): 662-665, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33107475

RESUMO

National identity programs like Aadhaar in India can play an unique role in identification of an individual and has numerous beneficial applications for the government and the citizens. The biometric records of finger prints and iris provided in the database can be useful for the forensic purpose. In unfortunate incidence of disasters, accidents, and criminal cases such as severe burnings, the identification of the victims is possible through dental profiling where fingerprint matching is not possible. Endodontic treatment includes the radiography for diagnosis of the lesion, during working length determination, obturation, and various other procedures. The variations in tooth anatomy and morphology, post-endo restorations, root canal fillings, and sometimes, endodontic mishaps are recorded in these radiographs. This record can play an important role in identification of a person in case of unfortunate happenings. So, it is suggested to include dental profiling in National Identification programs, and the purpose of this article is to highlight the role of root canal procedures in dental profiling.


Assuntos
Endodontia , Biometria , Assistência Odontológica , Humanos , Índia , Tratamento do Canal Radicular
9.
Niger J Clin Pract ; 23(9): 1312-1317, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32913173

RESUMO

Objective: The present study compared the ability of bleaching, resin infiltration and microabrasion to restore the appearance of existing white spot lesions (WSL) on tooth surfaces as close as possible to that of the original healthy enamel. Materials and Methods: Sixty extracted human teeth with WSL were randomly assigned to three treatment groups (20/group). Prior to treatment, the colour of the surrounding healthy enamel and the WSL were measured as the baseline and pre-treatment (PreRX) colours respectively using spectrophotometer based on CIE L*A*B. The L-value was used for the statistical comparison. WSLs in each group were treated respectively by bleaching, infiltration or microabrasion following the manufacturer's instructions. Colour measurement was repeated after treatment. Both intragroup and intergroup comparisons were performed using ANOVA followed by Tukey's multiple comparison test (α=0.05). Result: In all groups the mean L-values were significantly higher in PreRX WSL (P < 0.01; Tukey) compared to baseline (sound enamel). After treatment the difference in mean L-value between baseline and WSL increased significantly (P < 0.01, Tukey) in Bleaching and Microabrasion groups by 1.4% and 1% respectively, but decreased in Infiltration group by 3.4%. Thus resin infiltration decreased the L-value of the WSL, bringing it closer to the L-value of the sound enamel while bleaching and microabrasion increased the L-value. Conclusions: Among the three treatment modalities investigated in this study, resin infiltration was the most effective in masking the WSLs.


Assuntos
Cárie Dentária/terapia , Microabrasão do Esmalte , Estética Dentária , Resinas Sintéticas/uso terapêutico , Clareamento Dental/métodos , Biometria , Cárie Dentária/patologia , Humanos , Resinas Sintéticas/química , Espectrofotometria , Descoloração de Dente , Resultado do Tratamento
10.
PLoS One ; 15(9): e0239052, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32960924

RESUMO

Dendrochronology, the study of annual rings formed by trees and woody plants, has important applications in research of climate and environmental phenomena of the past. Since its inception in the late 19th century, dendrochronology has not had a way to quantify uncertainty about the years assigned to each ring (dating). There are, however, many woody species and sites where it is difficult or impossible to delimit annual ring boundaries and verify them with crossdating, especially in the lowland tropics. Rather than ignoring dating uncertainty or discarding such samples as useless, we present for the first time a probabilistic approach to assign expected ages with a confidence interval. It is proven that the cumulative age in a tree-ring time series advances by an amount equal to the probability that a putative growth boundary is truly annual. Confidence curves for the tree stem radius as a function of uncertain ages are determined. A sensitivity analysis shows the effect of uncertainty of the probability that a recognizable boundary is annual, as well as of the number of expected missing boundaries. Furthermore, we derive a probabilistic version of the mean sensitivity of a dendrochronological time series, which quantifies a tree's sensitivity to environmental variation over time, as well as probabilistic versions of the autocorrelation and process standard deviation. A computer code in Mathematica is provided, with sample input files, as supporting information. Further research is necessary to analyze frequency patterns of false and missing boundaries for different species and sites.


Assuntos
Biometria/métodos , Árvores/crescimento & desenvolvimento , Cronologia como Assunto , Clima , Modelos Teóricos , Fatores de Tempo , Árvores/metabolismo , Madeira
11.
PLoS One ; 15(9): e0238406, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32886667

RESUMO

INTRODUCTION: In cancer treatment an attempt has been made to pharmacologically regulate the proteasome functions, thus the aim was to test whether 20S proteasome chymotrypsin-like (ChT-L) activity has a role in glial brain tumors. Furthermore, we analyzed the correlation between proteasome activity and IL-8, CCL2, NF-κB1 and NF-κB2 concentrations, which impact on brain tumors has already been indicated. METHODS: Plasma 20S proteasome ChT-L activity was assayed using the fluorogenic peptide substrate Suc-Leu-Leu-Val-Tyr-AMC in the presence of SDS. IL-8, CCL2, NF-κB1 and NF-κB2 concentration was analyzed with the use of ELISA method. Immunohistochemistry for IDH1-R132H was done on 5-microns-thick formalin-fixed, paraffin-embedded tumor sections with the use of antibody specific for the mutant IDH1-R132H protein. Labelled streptavidin biotin kit was used as a detection system. RESULTS: Brain tumor patients had statistically higher 20S proteasome ChT-L activity (0.649 U/mg) compared to non-tumoral individuals (0.430 U/mg). IDH1 wild-type patients had statistically higher 20S proteasome ChT-L activity (1.025 U/mg) compared to IDH1 mutants (0.549 U/mg). 20S proteasome ChT-L activity in brain tumor patients who died as the consequence of a tumor (0.649) in the following 2 years was statistically higher compared to brain tumor patients who lived (0.430 U/mg). In brain tumor patients the 20S proteasome ChT-L activity positively correlated with IL-8 concentration. CONCLUSIONS: Elevated 20S proteasome ChT-L activity was related to the increased risk of death in glial brain tumor patients. A positive correlation between 20S proteasome ChT-L activity and IL-8 concentration may indicate the molecular mechanisms regulating glial tumor biology. Thus research on proteasomes may be important and should be carried out to verify if this protein complexes may represent a potential therapeutic target to limit brain tumor invasion.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Serina Endopeptidases/metabolismo , Adulto , Idoso , Biometria , Quimiocina CCL2/metabolismo , Quimotripsina/metabolismo , Cisteína Endopeptidases/metabolismo , Feminino , Glioma/patologia , Humanos , Interleucina-8/metabolismo , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Neuroglia/metabolismo , Neuroglia/patologia , Peptídeos/metabolismo , Complexo de Endopeptidases do Proteassoma/sangue , Proteólise , Serina Endopeptidases/sangue
12.
Medicine (Baltimore) ; 99(35): e21891, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32871919

RESUMO

To analyze the relationship between aortic measures and biometric parameters in a large cohort of consecutive patients undergoing computed tomography coronary angiography.1170 patients (717 men/453 women) performing computed tomography coronary angiography for coronary evaluation were retrospectively evaluated. Aortic diameters and areas were measured at reproducible anatomic landmarks, perpendicular to the axis of vessel, at the level of the aortic root (AoR), the sinotubular junction (STJ), and the tubular ascending aorta (TAo). Biometric parameters and cardiovascular risk factors were recorded.The average values of AoR, STJ, and TAo were 35.63 ±â€Š5.00 mm, 30.56 ±â€Š4.82 mm, 35.07 ±â€Š5.84 mm. Hypertension was significantly associated with aortic dimensions.Aortic measures were significantly different between men and women (37.56 ±â€Š4.77 mm vs 32.58 ±â€Š3.68 mm for AoR, 31.88 ±â€Š4.84 mm vs 28.47 ±â€Š3.98 mm for STJ and 35.93 ±â€Š5.86 mm vs 33.70 ±â€Š5.54 mm for TAo) (P < .001) and linearly increased with age. Low Spearman correlation coefficients were found and the correlation of TAo diameters with age displayed the highest values (ρ = 0.372 for male and ρ = 0.373 for female, P < .001). Multiple linear regression analysis models were compared by R. The best model used body surface area (BSA) and age as independent variables and TAo diameter as dependent variable (R = 0.29 for AoR; R = 0.21 for STJ, and R = 0.20 for TAo).In conclusion, in our population low correlation between aortic dimensions and biometric parameters highlights the difficulty of identifying normal ranges, as well as issues related to normalization using conventional biometric parameters.


Assuntos
Aorta/anatomia & histologia , Aorta/diagnóstico por imagem , Biometria , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/patologia , Angiografia Coronária , Tomografia Computadorizada por Raios X , Fatores Etários , Idoso , Superfície Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
13.
PLoS One ; 15(8): e0236954, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760106

RESUMO

To infer the parameters of mechanistic models with intractable likelihoods, techniques such as approximate Bayesian computation (ABC) are increasingly being adopted. One of the main disadvantages of ABC in practical situations, however, is that parameter inference must generally rely on summary statistics of the data. This is particularly the case for problems involving high-dimensional data, such as biological imaging experiments. However, some summary statistics contain more information about parameters of interest than others, and it is not always clear how to weight their contributions within the ABC framework. We address this problem by developing an automatic, adaptive algorithm that chooses weights for each summary statistic. Our algorithm aims to maximize the distance between the prior and the approximate posterior by automatically adapting the weights within the ABC distance function. Computationally, we use a nearest neighbour estimator of the distance between distributions. We justify the algorithm theoretically based on properties of the nearest neighbour distance estimator. To demonstrate the effectiveness of our algorithm, we apply it to a variety of test problems, including several stochastic models of biochemical reaction networks, and a spatial model of diffusion, and compare our results with existing algorithms.


Assuntos
Algoritmos , Teorema de Bayes , Biometria/métodos , Fenômenos Bioquímicos , Simulação por Computador , Funções Verossimilhança , Cadeias de Markov , Redes e Vias Metabólicas , Modelos Biológicos , Modelos Estatísticos , Método de Monte Carlo , Análise de Regressão , Processos Estocásticos
14.
Ecol Lett ; 23(10): 1511-1521, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32776667

RESUMO

The persistence of a species in a given place not only depends on its intrinsic capacity to consume and transform resources into offspring, but also on how changing environmental conditions affect its growth rate. However, the complexity of factors has typically taken us to choose between understanding and predicting the persistence of species. To tackle this limitation, we propose a probabilistic approach rooted on the statistical concepts of ensemble theory applied to statistical mechanics and on the mathematical concepts of structural stability applied to population dynamics models - what we call structural forecasting. We show how this new approach allows us to estimate a probability of persistence for single species in local communities; to understand and interpret this probability conditional on the information we have concerning a system; and to provide out-of-sample predictions of species persistence as good as the best experimental approaches without the need of extensive amounts of data.


Assuntos
Biometria , Ecossistema , Previsões , Modelos Biológicos , Dinâmica Populacional
16.
Ophthalmologe ; 117(10): 973-988, 2020 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-32857270

RESUMO

BACKGROUND: Empirical models have been an integral part of everyday clinical practice in ophthalmology since the introduction of the Sanders-Retzlaff-Kraff (SRK) formula. Recent developments in the field of statistical learning (artificial intelligence, AI) now enable an empirical approach to a wide range of ophthalmological questions with an unprecedented precision. OBJECTIVE: Which criteria must be considered for the evaluation of AI-related studies in ophthalmology? MATERIAL AND METHODS: Exemplary prediction of visual acuity (continuous outcome) and classification of healthy and diseased eyes (discrete outcome) using retrospectively compiled optical coherence tomography data (50 eyes of 50 patients, 50 healthy eyes of 50 subjects). The data were analyzed with nested cross-validation (for learning algorithm selection and hyperparameter optimization). RESULTS: Based on nested cross-validation for training, visual acuity could be predicted in the separate test data-set with a mean absolute error (MAE, 95% confidence interval, CI of 0.142 LogMAR [0.077; 0.207]). Healthy versus diseased eyes could be classified in the test data-set with an agreement of 0.92 (Cohen's kappa). The exemplary incorrect learning algorithm and variable selection resulted in an MAE for visual acuity prediction of 0.229 LogMAR [0.150; 0.309] for the test data-set. The drastic overfitting became obvious on comparison of the MAE with the null model MAE (0.235 LogMAR [0.148; 0.322]). CONCLUSION: Selection of an unsuitable measure of the goodness-of-fit, inadequate validation, or withholding of a null or reference model can obscure the actual goodness-of-fit of AI models. The illustrated pitfalls can help clinicians to identify such shortcomings.


Assuntos
Inteligência Artificial , Oftalmologia , Biometria , Humanos , Estudos Retrospectivos , Acuidade Visual
17.
BMC Bioinformatics ; 21(1): 315, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32677882

RESUMO

BACKGROUND: Recognition is an essential function of human beings. Humans easily recognize a person using various inputs such as voice, face, or gesture. In this study, we mainly focus on DL model with multi-modality which has many benefits including noise reduction. We used ResNet-50 for extracting features from dataset with 2D data. RESULTS: This study proposes a novel multimodal and multitask model, which can both identify human ID and classify the gender in single step. At the feature level, the extracted features are concatenated as the input for the identification module. Additionally, in our model design, we can change the number of modalities used in a single model. To demonstrate our model, we generate 58 virtual subjects with public ECG, face and fingerprint dataset. Through the test with noisy input, using multimodal is more robust and better than using single modality. CONCLUSIONS: This paper presents an end-to-end approach for multimodal and multitask learning. The proposed model shows robustness on the spoof attack, which can be significant for bio-authentication device. Through results in this study, we suggest a new perspective for human identification task, which performs better than in previous approaches.


Assuntos
Biometria , Aprendizado Profundo , Algoritmos , Eletrocardiografia , Humanos
20.
PLoS One ; 15(7): e0236137, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32687526

RESUMO

This retrospective study was aimed to compare prediction errors from various combinations of biometric data generated using optical coherence tomography (OCT) and develop a new intraocular lens (IOL) formula using biometric data. 145 eyes from 145 patients who underwent femtosecond laser-assisted cataract surgery (FLACS) were enrolled to the present study and they were divided into a training set (n = 92) and a test set (n = 53). Preoperative axial length (AL) and corneal radius were measured using partial coherence interferometry. The anterior chamber depth (ACD), lens meridian parameter (LMP), lens thickness (LT), thickness of anterior and posterior parts of the crystalline lens (aLT and pLT), and anterior segment length were measured by OCT. From a training set, we developed eight regression equations and analyzed the predictive accuracy. The regression equation using AL, LMP, and pLT (-1.143 + 0.148*AL + 0.428*LMP + 0.254*pLT) showed the strongest correlation with effective lens position (ELP) and smallest standard deviation of ELP prediction error. IOL formula generated using AL, LMP, and pLT yielded the highest predictive accuracy. In a test set, the new IOL formula also produced narrowest range of prediction error, smallest median absolute error, and highest percentages within ±0.25, ±0.50 than existing IOL formulas. The IOL formula considering AL, LMP and pLT will help to improve predictive accuracy in FLACS.


Assuntos
Biometria , Imageamento Tridimensional , Lentes Intraoculares , Tomografia de Coerência Óptica , Idoso , Idoso de 80 Anos ou mais , Extração de Catarata , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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