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1.
Sci Rep ; 13(1): 12865, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553424

RESUMO

Osteoporosis is a disease characterized by impairment of bone microarchitecture that causes high socioeconomic impacts in the world because of fractures and hospitalizations. Although dual-energy X-ray absorptiometry (DXA) is the gold standard for diagnosing the disease, access to DXA in developing countries is still limited due to its high cost, being present only in specialized hospitals. In this paper, we analyze the performance of Osseus, a low-cost portable device based on electromagnetic waves that measures the attenuation of the signal that crosses the medial phalanx of a patient's middle finger and was developed for osteoporosis screening. The analysis is carried out by predicting changes in bone mineral density using Osseus measurements and additional common risk factors used as input features to a set of supervised classification models, while the results from DXA are taken as target (real) values during the training of the machine learning algorithms. The dataset consisted of 505 patients who underwent osteoporosis screening with both devices (DXA and Osseus), of whom 21.8% were healthy and 78.2% had low bone mineral density or osteoporosis. A cross-validation with k-fold = 5 was considered in model training, while 20% of the whole dataset was used for testing. The obtained performance of the best model (Random Forest) presented a sensitivity of 0.853, a specificity of 0.879, and an F1 of 0.859. Since the Random Forest (RF) algorithm allows some interpretability of its results (through the impurity check), we were able to identify the most important variables in the classification of osteoporosis. The results showed that the most important variables were age, body mass index, and the signal attenuation provided by Osseus. The RF model, when used together with Osseus measurements, is effective in screening patients and facilitates the early diagnosis of osteoporosis. The main advantages of such early screening are the reduction of costs associated with exams, surgeries, treatments, and hospitalizations, as well as improved quality of life for patients.


Assuntos
Osteoporose , Qualidade de Vida , Humanos , Densidade Óssea , Osteoporose/diagnóstico por imagem , Absorciometria de Fóton/métodos , Programas de Rastreamento , Aprendizado de Máquina , Radiação Eletromagnética
2.
Artigo em Inglês | MEDLINE | ID: mdl-36498280

RESUMO

The improvement of laboratory diagnosis is a critical step for the reduction of syphilis cases around the world. In this paper, we present the development of an impedance-based method for detecting T. pallidum antigens and antibodies as an auxiliary tool for syphilis laboratory diagnosis. We evaluate the voltammetric signal obtained after incubation in carbon or gold nanoparticle-modified carbon electrodes in the presence or absence of Poly-L-Lysine. Our results indicate that the signal obtained from the electrodes was sufficient to distinguish between infected and non-infected samples immediately (T0') or 15 min (T15') after incubation, indicating its potential use as a point-of-care method as a screening strategy.


Assuntos
Nanopartículas Metálicas , Sífilis , Humanos , Treponema pallidum , Ouro , Anticorpos Antibacterianos , Sífilis/diagnóstico , Carbono
3.
Ultrasonics ; 106: 106139, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32298848

RESUMO

The objective of this work is to assess, on metrological basis, the average grey-levels (AVGL) calculated from B-Mode images for estimating temperature variations non-invasively in different kinds of tissues. Thermal medicine includes several thermal therapies, being hyperthermia the most noted and well known. Recently, efforts have been made to understand the benefits of ultrasound hyperthermia at mild temperature levels, i.e., between 39 °C and 41 °C. Moreover, the best practices on ultrasound bio-effects research have been encouraged by recommending that temperature rise in the region of interest should be measured even when a thermal mechanism is not being tested. In this work, the average grey-levels (AVGL) calculated from B-Mode images were assessed for non-invasive temperature estimation in a porcine tissue sample containing two different tissue types, fat and muscle, with temperature varying from 35 °C to 41 °C. The sample was continuously imaged with an ultrasound scanner, and simultaneously the temperature was measured. The achieved results were assessed under the light of the measurement uncertainty in order to allow comparability among different ultrasound thermometry methods. The highest expanded uncertainty of estimating temperature variation using AVGL was determined as 0.68 °C.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Termometria/métodos , Ultrassonografia/métodos , Animais , Técnicas In Vitro , Imagens de Fantasmas , Suínos
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 4470-4, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26737287

RESUMO

This work introduces a new methodology for the early detection of epileptic seizure based on the WiSARD weightless neural network model and a new approach in terms of preprocessing the electroencephalogram (EEG) data. WiSARD has, among other advantages, the capacity of perform the training phase in a very fast way. This speed in training is due to the fact that WiSARD's neurons work like Random Access Memories (RAM) addressed by input patterns. Promising results were obtained in the anticipation of seizure onsets in four representative patients from the European Database on Epilepsy (EPILEPSIAE). The proposed seizure early detection WNN architecture was explored by varying the detection anticipation (δ) in the 2 to 30 seconds interval, and by adopting 2 and 3 seconds as the width of the Sliding Observation Window (SOW) input. While in the most challenging patient (A) one obtained accuracies from 99.57% (δ=2s; SOW=3s) to 72.56% (δ=30s; SOW=2s), patient D seizures could be detected in the 99.77% (δ=2s; SOW=2s) to 99.93% (δ=30s; SOW=3s) accuracy interval.


Assuntos
Epilepsia , Diagnóstico Precoce , Eletroencefalografia , Humanos , Redes Neurais de Computação , Convulsões
5.
Neotrop Entomol ; 35(5): 573-8, 2006.
Artigo em Português | MEDLINE | ID: mdl-17144127

RESUMO

Field sampling was carried out in Ouro Preto d'Oeste - Rondônia (10 degrees 45'S and 62 degrees 15'W) to evaluate the mycobiota associated with Hypothenemus hampei Ferrari [cuticle, mouth, prothorax (mycangia), gut and feces] and its galleries on berries of Coffea canephora Pierre. Ten genera (201 isolates) were directly related with the insect while five genera (20 isolates) were related with galleries on berries. All the genera identified in the insects were also present in their galleries, what indicates that boring may be an active way of fungi inoculation by H. hampei. The fungi genera were more diverse in the mouth and prothorax of borers, and lower in feces. Fusarium, Penicillium and Geotrichum, with abundance of 55.7, 24.3 and 10.8%, respectively, were dominant genera. In the galleries Fusarium, Geotrichum, Trichoderma and Aspergillus with abundance of 33.3, 29.6, 18.5 and 14.8%, respectively, were dominant genera. The overall presence of Fusarium in coffee berry borer and its galleries) reinforces previous indications of a close interaction between H. hampei-Fusarium. The presence of Aspergillus and Penicillium emphasizes the possibility of "ochratoxin dispersion" by the borer. This work provides the first record of the mycobiota associated with H. hampei in C. canephora. Among the identified genera, Cephalosporium, Geotrichum and Oidiodendrum were recorded for the first time in association with H. hampei and its galleries in C. canephora.


Assuntos
Coffea/microbiologia , Besouros/microbiologia , Fungos/isolamento & purificação , Animais
6.
Neotrop Entomol ; 35(4): 560-2, 2006.
Artigo em Português | MEDLINE | ID: mdl-17061809

RESUMO

Adults of Cephalonomia stephanoderis Betrem were detected (in November 2003) during the sampling of Coffea canephora Pierre ex A. Froehner berries damaged by Hypothenemus hampei Ferrari (Coleoptera: Scolytidae) in Ouro Preto D'Oeste - Rondônia, Brazil (10 degrees 45'S and 62 degrees 15'W). From January to July 2004, the parasitoid was monthly sampled in 200 berries damaged by H. hampei. Probably, C. stephanoderis can already exert some parasitism pressure at the coffee berry borer population. The occurrence of this parasitoid in natural conditions points out to another alternative for the biological control of the H. hampei in Rondônia. This is the first record of C. stephanoderis in coffee plantations of the Brazilian Amazonia.


Assuntos
Agricultura , Coffea/parasitologia , Himenópteros , Animais , Brasil
7.
Neotrop. entomol ; 35(5): 573-578, Sept.-Oct. 2006. tab
Artigo em Português | LILACS | ID: lil-451217

RESUMO

Amostragens de campo foram realizadas em Ouro Preto d'Oeste (10°45'S e 62°15'W) para avaliar a micobiota associada a Hypothenemus hampei Ferrari [cutícula, aparelho bucal, protórax (micângia), tubo digestivo e fezes] e suas galerias em frutos de Coffea canephora Pierre. Dez gêneros (201 isolados) estavam diretamente relacionados com o inseto, enquanto cinco gêneros (20 isolados) estavam relacionados com galerias do inseto nos frutos. Todos os gêneros identificados associados aos insetos estavam também presentes nas suas galerias, o que indica que o broqueamento pode significar um modo ativo de inoculação de fungos por H. hampei. Na broca, a diversidade de gêneros de fungos foi maior no aparelho bucal e protórax e menor nas fezes. Fusarium, Penicillium e Geotrichum, com abundâncias de 55,7, 24,3 e 10,8 por cento, respectivamente, foram os gêneros dominantes. Nas galerias Fusarium, Geotrichum, Trichoderma e Aspergillus com abundância de 33,3; 29,6; 18,5 e 14,8 por cento, respectivamente, foram os gêneros dominantes. A presença de Fusarium no inseto e suas galerias reforça indicações anteriores de uma interação íntima entre H. hampei-Fusarium. A presença de Aspergillus e Penicillium enfatiza a possibilidade de dispersão da ocratoxina pela broca. Este trabalho fornece o primeiro registro da micobiota associada a H. hampei em C. canephora. Entre os gêneros identificados, Cephalosporium, Geotrichum e Oidiodendrum foram registrados pela primeira vez em associação com o inseto e suas galerias em C. canephora.


Field sampling was carried out in Ouro Preto d'Oeste Rondônia (10°45'S and 62°15'W) to evaluate the mycobiota associated with Hypothenemus hampei Ferrari [cuticle, mouth, prothorax (mycangia), gut and feces] and its galleries on berries of Coffea canephora Pierre. Ten genera (201 isolates) were directly related with the insect while five genera (20 isolates) were related with galleries on berries. All the genera identified in the insects were also present in their galleries, what indicates that boring may be an active way of fungi inoculation by H. hampei. The fungi genera were more diverse in the mouth and prothorax of borers, and lower in feces. Fusarium, Penicillium and Geotrichum, with abundance of 55.7, 24.3 and 10.8 percent, respectively, were dominant genera. In the galleries Fusarium, Geotrichum, Trichoderma and Aspergillus with abundance of 33.3, 29.6, 18.5 and 14.8 percent, respectively, were dominant genera. The overall presence of Fusarium in coffee berry borer and its galleries) reinforces previous indications of a close interaction between H. hampei-Fusarium. The presence of Aspergillus and Penicillium emphasizes the possibility of "ochratoxin dispersion" by the borer. This work provides the first record of the mycobiota associated with H. hampei in C. canephora. Among the identified genera, Cephalosporium, Geotrichum and Oidiodendrum were recorded for the first time in association with H. hampei and its galleries in C. canephora.


Assuntos
Animais , Besouros/microbiologia , Coffea/microbiologia , Fungos/isolamento & purificação
8.
Neotrop. entomol ; 35(4): 560-562, July-Aug. 2006. graf
Artigo em Português | LILACS | ID: lil-451259

RESUMO

Adultos de Cephalonomia stephanoderis Betrem foram detectados em novembro de 2003 durante amostragem de frutos de Coffea canephora Pierre ex A. Froehner danificados por Hypothenemus hampei Ferrari (Coleoptera: Scolytidae) em Ouro Preto D'Oeste, RO (10°45'S e 62°15'W). De janeiro a julho de 2004, o parasitóide foi amostrada mensalmente em 200 frutos danificados por H. hampei. Provavelmente, C. stephanoderis exerça alguma pressão de parasitismo sobre a população da broca-do-café. A ocorrência do parasitóide em condições naturais aponta para outra alternativa de controle biológico de H. hampei em Rondônia. Este é o primeiro registro de C. stephanoderis em plantações de café na Amazônia brasileira.


Adults of Cephalonomia stephanoderis Betrem were detected (in November 2003) during the sampling of Coffea canephora Pierre ex A. Froehner berries damaged by Hypothenemus hampei Ferrari (Coleoptera: Scolytidae) in Ouro Preto D'Oeste - Rondônia, Brazil (10°45'S and 62°15'W). From January to July 2004, the parasitoid was monthly sampled in 200 berries damaged by H. hampei. Probably, C. stephanoderis can already exert some parasitism pressure at the coffee berry borer population. The occurrence of this parasitoid in natural conditions points out to another alternative for the biological control of the H. hampei in Rondônia. This is the first record of C. stephanoderis in coffee plantations of the Brazilian Amazonia.


Assuntos
Animais , Agricultura , Coffea/parasitologia , Himenópteros , Brasil
9.
Neotrop. entomol ; 35(3): 390-394, May-June 2006. graf, tab
Artigo em Português | LILACS | ID: lil-455803

RESUMO

A queda dos frutos brocados por Hypothenemus hampei (Ferrari) pode ser o principal fator de perda durante a frutificação do café. Entretanto, apenas os frutos brocados que permanecem no solo antes de um novo período de frutificação têm sido reconhecidos como causadores de impacto no nível de broqueamento de frutos em formação. Neste trabalho, investigou-se, ao longo do período de frutificação, a presença, nas plantas e no solo, de frutos de Coffea canephora cv. Conilon brocados por H. hampei, em Ouro Preto d'Oeste, RO. As coletas foram realizadas, semanalmente, entre dezembro de 2000 e junho de 2001. Os dados obtidos foram submetidos à análise de regressão de sobrevivência, baseado no modelo de Weibull. Durante o período de frutificação do café, a queda dos frutos ocorre continuamente e a presença de frutos brocados por H. hampei chega a ser, em média, 4 a 20 vezes maior no solo (P < 2,3x10-18, n = 62747) do que nas plantas. Argumenta-se que a incorporação do "ambiente solo" na determinação de ações de manejo integrado possa apontar novas tecnologias para o controle da broca.


Falling of berries bored by Hypothenemus hampei (Ferrari) may be the major loosing factor during the fruiting period. However, only those bored berries which remain in the soil surface before a new yielding period have been recognized as responsible for the damage level Ho achieved by new developing berries. In this paper, we investigated in the plants and in the soil surface, the presence of Coffea canephora cv. Conilon berries bored by H. hampei during the yielding period in Ouro Preto d'Oeste, Rondônia, Brazil. We took samples, weekly, from December 2000 to June 2001. The data were submitted to the Surviving Regression Analysis, based on a censored Weibull model. During the yielding period, berries fall down continuously and, in average, the proportion of H. hampei bored berries was 4 to 20 times higher in the soil (P < 2,3x10-18, n = 62,747) than in the plants. Thus, we argue that adding the "soil environment" to the integrated management strategies could point to new technologies for the control of this insect.


Assuntos
Besouros/classificação , Besouros/parasitologia , Besouros/patogenicidade , Café/imunologia , Café/parasitologia
10.
Neotrop Entomol ; 35(3): 390-4, 2006.
Artigo em Português | MEDLINE | ID: mdl-18575701

RESUMO

Falling of berries bored by Hypothenemus hampei (Ferrari) may be the major loosing factor during the fruiting period. However, only those bored berries which remain in the soil surface before a new yielding period have been recognized as responsible for the damage level Ho achieved by new developing berries. In this paper, we investigated in the plants and in the soil surface, the presence of Coffea canephora cv. Conilon berries bored by H. hampei during the yielding period in Ouro Preto d'Oeste, Rondônia, Brazil. We took samples, weekly, from December 2000 to June 2001. The data were submitted to the Surviving Regression Analysis, based on a censored Weibull model. During the yielding period, berries fall down continuously and, in average, the proportion of H. hampei bored berries was 4 to 20 times higher in the soil (P < 2,3 x 10-18, n = 62,747) than in the plants. Thus, we argue that adding the "soil environment" to the integrated management strategies could point to new technologies for the control of this insect.


Assuntos
Coffea/fisiologia , Coffea/parasitologia , Besouros/fisiologia , Frutas/fisiologia , Frutas/parasitologia , Animais , Solo , Fatores de Tempo
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