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1.
Sensors (Basel) ; 23(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36772460

RESUMO

Fe3Co67Cr3Si15B12 ribbons with a high degree of flexibility and excellent corrosion stability were produced by rapid quenching technique. Their structural, magnetic, and thermomagnetic (Anomalous Nernst Effect) properties were studied both in an as-quenched (NR) state and after stress annealing during 1 h at the temperature of 350 °C and a specific load of 230 MPa (AR). X-ray diffraction was used to verify the structural characteristics of our ribbons. Static magnetic properties were explored by inductive technique and vibrating sample magnetometry. The thermomagnetic curves investigated through the Anomalous Nernst Effect are consistent with the obtained magnetization results, presenting a linear response in the thermomagnetic signal, an interesting feature for sensor applications. Additionally, Anomalous Nernst Effect coefficient SANE values of 2.66µV/K and 1.93µV/K were estimated for the as-quenched and annealed ribbons, respectively. The interplay of the low magnetostrictive properties, soft magnetic behavior, linearity of the thermomagnetic response, and flexibility of these ribbons place them as promising systems to probe curved surfaces and propose multifunctional devices, including magnetic field-specialized sensors.

2.
Parasitology ; 149(1): 10-14, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34218833

RESUMO

This research aims to determine whether the combination of epidemiological and clinical features can predict malaria. Diagnostic investigation detected 22.3% of individuals with Plasmodium vivax (P. vivax) malaria, with significant predominance of the male gender. The malaria triad (fever, chills and headache) had a more expressive frequency (81.1%) in individuals with positive thick blood than those with negative thick blood smear (65.1%), although there was no statistical significance. Among the variables analysed as predictive for positive thick blood smear, it was observed that personal history of travel to an endemic malaria area and past malaria infection (PMI) were significantly associated with malaria, even in multiple logistic regression. Fever had the higher sensitivity (94.6%) and past malaria history had the greater specificity (68.2%), with accuracy of 23.5% and 67.5%, respectively. In combined analysis, fever with chills had the highest sensitivity (91.9%), but low accuracy (38.5%). High specificity (91.5%) was found in the association of malaria triad, PMI and history of travel to endemic malaria area (which along with anorexia, was higher 94.6%), with good accuracy (80.7%), suggesting that the screening of patients for performing thick blood smear can be based on these data. The epidemiological features and the malaria triad (fever, chills and headache) can be predictors for identification of malaria patients, concurring to precocious diagnosis and immediate treatment of individuals with malaria.


Assuntos
Malária Falciparum , Malária Vivax , Malária , Brasil/epidemiologia , Humanos , Malária/diagnóstico , Malária/epidemiologia , Malária Falciparum/epidemiologia , Malária Vivax/diagnóstico , Malária Vivax/epidemiologia , Masculino , Plasmodium vivax , Viagem
3.
Sensors (Basel) ; 22(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36236764

RESUMO

Titanium-copper alloy films with stoichiometry given by Ti1-xCux were produced by magnetron co-sputtering technique and analyzed in order to explore the suitability of the films to be applied as resistive temperature sensors with antimicrobial properties. For that, the copper (Cu) amount in the films was varied by applying different DC currents to the source during the deposition in order to change the Cu concentration. As a result, the samples showed excellent thermoresistivity linearity and stability for temperatures in the range between room temperature to 110 °C. The sample concentration of Ti0.70Cu0.30 has better characteristics to act as RTD, especially the αTCR of 1990 ×10-6°C-1. The antimicrobial properties of the Ti1-xCux films were analyzed by exposing the films to the bacterias S. aureus and E. coli, and comparing them with bare Ti and Cu films that underwent the same protocol. The Ti1-xCux thin films showed bactericidal effects, by log10 reduction for both bacteria, irrespective of the Cu concentrations. As a test of concept, the selected sample was subjected to 160 h reacting to variations in ambient temperature, presenting results similar to a commercial temperature sensor. Therefore, these Ti1-xCux thin films become excellent antimicrobial candidates to act as temperature sensors in advanced coating systems.


Assuntos
Anti-Infecciosos , Titânio , Ligas , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias , Cobre , Escherichia coli , Staphylococcus aureus , Temperatura
4.
Ann Vasc Surg ; 72: 666.e23-666.e32, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33333194

RESUMO

Saccular superior vena cava aneurysms (SVCAs) are one of the rarest causes of mediastinal masses. Seventy years after the first published case report, to the best of our knowledge, fewer than 30 cases have been described in the literature. This article provides an overview of the peculiarities regarding diagnosis and treatment performed in these cases and addresses the protocol adopted in our case report. We present a saccular aneurysm resected through median sternotomy, under cardiopulmonary bypass and superior vena cava reconstruction using a bovine pericardial patch.


Assuntos
Aneurisma/cirurgia , Pericárdio/transplante , Procedimentos de Cirurgia Plástica , Procedimentos Cirúrgicos Vasculares , Veia Cava Superior/cirurgia , Adolescente , Adulto , Idoso , Aneurisma/diagnóstico por imagem , Animais , Ponte Cardiopulmonar , Bovinos , Feminino , Xenoenxertos , Humanos , Masculino , Pessoa de Meia-Idade , Esternotomia , Resultado do Tratamento , Veia Cava Superior/diagnóstico por imagem , Adulto Jovem
5.
Ann Hepatol ; 20: 100253, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32949785

RESUMO

INTRODUCTION/AIMS: Liver fibrosis assessment is a key issue in the evaluation of nonalcoholic fatty liver disease (NAFLD) patients. In the present study, we aimed to validate a noninvasive marker panel to assess significant and advanced fibrosis in these patients. METHOD: 126 biopsy-proven NAFLD patients were included. NAFLD diagnosis was based on histological criteria. Fibrosis stages were determined according to NASH-Clinical Research Network criteria. Clinical and laboratorial data were collected during the interval of three months before or after liver biopsy. Histological fibrosis stages were classified as significant fibrosis (F2-F4) and advanced fibrosis (F3-F4). Five serum biomarkers [hyaluronic acid (HA), collagen type IV (cIV), procollagen type III (PC III), laminin (LN) and cholylglycine (CG)] were assessed by chemiluminescence immunoassays. RESULTS: Most patients were female (61.61%), mean age: 55.7 ±â€¯9.13 years old and mean BMI was 32.1 ±â€¯5.9 kg/m2. Prevalence of diabetes, dyslipidemia, arterial hypertension, and metabolic syndrome was 68.75%, 82.29%, 63.54% and 81.05%, respectively. Patients with cIV above 30 ng/mL had a 5.57-times (IC: 1.86-16.69) the chance of having significant fibrosis and 7.61-times (IC: 2.27-25.54) the chance of having advanced fibrosis versus patients with values below 30 ng/mL. HA, PC III, LN and CG did not detect the presence of significant and advanced fibrosis. The AUROC of clV for detection of significant (0.718) and advanced fibrosis (0.791) was better than that of other serum biomarkers. CONCLUSION: Type 4 collagen could predict the presence of significant and advanced fibrosis in NAFLD patients and it would be a useful tool in routine clinical practice.


Assuntos
Colágeno Tipo IV/sangue , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Adulto , Idoso , Biomarcadores/sangue , Colágeno Tipo III/sangue , Feminino , Ácido Glicocólico/sangue , Humanos , Ácido Hialurônico/sangue , Laminina/sangue , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações
6.
Sensors (Basel) ; 21(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34577350

RESUMO

We investigated the magnetization dynamics through the magnetoimpedance effect in an integrated YIG/Pt-stripline system in the frequency range of 0.5 up to 2.0 GHz. Specifically, we explore the dependence of the dynamic magnetic behavior on the field orientation by analyzing beyond the traditional longitudinal magnetoimpedance effect of the transverse and perpendicular setups. We disclose here the strong dependence of the effective damping parameter on the field orientation, as well as verification of the very-low damping parameter values for the longitudinal and transverse configurations. We find considerable sensitivity results, bringing to light the facilities to integrate ferrimagnetic insulators in current and future technological applications.

7.
Ann Hepatol ; 19(6): 622-626, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32919087

RESUMO

INTRODUCTION AND AIMS: Several non-invasive scoring systems have been developed and validated worldwide to predict the risk of liver fibrosis in nonalcoholic fatty liver disease (NAFLD). However, information about the performance of these systems in Latin American populations is scarce. Our aim was to evaluate the performance of the Hepamet Fibrosis Score, Fibrosis-4 (FIB-4) and the NAFLD Fibrosis Score (NFS) in a mixed Latin American group of NAFLD patients. METHODS: Clinical, laboratory and liver biopsy data collected from 379 biopsy-proven NAFLD patients from Latin American tertiary health centers were reviewed. Histological fibrosis stages were classified using the Kleiner score. Accuracy was determined, and new fibrosis score thresholds were calculated to better compare the performances of non-invasive tests and to explore their usefulness in excluding fibrosis. RESULTS: The distribution of fibrosis stages among the sample population was as follows: F0 (45%), F1 (27%), F2 (8%), F3 (16%) and F4 (4%). Using modified thresholds, the areas under the ROC curves (AUROC) for Hepamet and FIB-4 (0.73 and 0.74, respectively) to detect significant fibrosis were higher than that of NFS (0.58). However, the AUROCs of the three scores were not significantly different in advanced fibrosis and cirrhosis. To exclude fibrosis, we calculated lower cutoffs than standard thresholds for Hepamet, FIB-4 and NFS with similar performances. CONCLUSION: Thresholds of non-invasive fibrosis scores (Hepamet, FIB-4 and NFS) can be modified to maximize diagnostic accuracy in Latin American patients with NAFLD.


Assuntos
Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologia , Adulto , Estudos Transversais , Feminino , Indicadores Básicos de Saúde , Humanos , América Latina , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , América do Sul
8.
Lung ; 197(3): 259-265, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30900014

RESUMO

The lung acinus is the most distal portion of the airway responsible for the gas exchange. The normal acini are not visible on conventional computed tomography (CT), but the advent of micro-CT improved the understanding of the microarchitecture of healthy acini. The comprehension of the acinar architecture is pivotal for the understanding of CT findings of diseases that involve the acini. Centriacinar emphysema, for example, presents as round areas of low attenuation due to the destruction of the most central acini with compensatory enlargement of proximal acini due to alveolar wall destruction. In pulmonary fibrosis, intralobular septal fibrosis manifests as acinar wall thickening with an overlap of acinar collapse and compensatory dilation of surrounding acini constituting the cystic disease typical of the usual interstitial pneumonia pattern. This is a state-of-the-art review to describe the acinar structure from the micro-CT perspective and display how the comprehension of the acinar structure can aid in the interpretation of its microarchitecture disruption on conventional CT.


Assuntos
Pulmão/diagnóstico por imagem , Alvéolos Pulmonares/diagnóstico por imagem , Enfisema Pulmonar/diagnóstico por imagem , Fibrose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/diagnóstico por imagem , Humanos , Tomografia Computadorizada por Raios X , Microtomografia por Raio-X
9.
Lung ; 195(6): 769-774, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29032479

RESUMO

PURPOSES: Considering that pulmonary arterial obstruction decreases venous flow, we hypothesized that filling defects in pulmonary veins can be identified in areas adjacent to pulmonary embolism (PE). This sign was named the "pulmonary vein sign" (PVS), and we evaluated its prevalence and performance for PE diagnosis in computed tomography pulmonary angiography (CTPA). METHODS: This retrospective study enrolled consecutive patients with clinical suspicion of PE who underwent CTPA scan. The PVS was defined by the following criteria: (a) presence of a homogeneous filling defect of at least 2 cm in a pulmonary vein; (b) attenuation of the left atrium > 160 Hounsfield units. Using the cases that presented PE on CTPA as reference, sensitivity, specificity, and positive and negative predictive values were calculated for PVS. RESULTS: In total, 119 patients (73 female; mean age, 62 years) were included in this study. PE was diagnosed in 44 (35.8%) patients. The PVS was present in 16 out of 44 patients with PE. Sensitivity was 36.36% (95% confidence interval (CI) 22.83-52.26%); specificity, 98.67% (95% CI 91.79-99.93%); positive predictive value, 94.12% (95% CI 69.24-99.69%); negative predictive value, 72.55% (95% CI 62.67-80.70%). The Kappa index for the PVS was good (0.801; 95% CI 0.645-0.957). PVS was correlated with lobar and segmental pulmonary embolism (p < 0.01). CONCLUSION: Despite a low sensitivity, presence of the pulmonary vein sign was highly specific for PE, with a good agreement between readers. This sign could contribute for PE diagnosis on CTPA studies.


Assuntos
Angiografia por Tomografia Computadorizada , Embolia Pulmonar/diagnóstico por imagem , Veias Pulmonares/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Retrospectivos , Adulto Jovem
10.
Lung ; 195(4): 389-395, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28612239

RESUMO

Dengue fever is an arboviral disease transmitted to humans through the bites of infected female Aedes mosquitoes. Dengue virus is a member of the Flaviviridae family, and human infection can be caused by any of the four antigenically distinct serotypes (DENV 1-4). The infection has become recognized as the most important and prevalent arboviral disease in humans, endemic in almost 100 countries worldwide. Nearly 3 billion people live in areas with transmission risk. Autochthonous transmission of the virus in previously disease-free areas, increased incidence in endemic areas, and epidemic resurgence in controlled regions could increase the risk of contracting more severe forms of the disease, such as dengue hemorrhagic fever (DHF)/dengue shock syndrome (DSS). Symptomatic dengue virus infection can present with a wide range of clinical manifestations, from mild fever to life-threatening DSS. Thoracic complications may manifest as pleural effusion, pneumonitis, non-cardiogenic pulmonary edema, and hemorrhage/hemoptysis. No vaccine is currently available and no specific treatment for dengue fever exists, but prevention and prompt management of complications in patients with DHF can help reduce mortality. This review describes the main clinical, pathological, and imaging findings of thoracic involvement in DHF.


Assuntos
Aedes/virologia , Vírus da Dengue/patogenicidade , Hemoptise/virologia , Pulmão/virologia , Dengue Grave/virologia , Animais , Biópsia , Vacinas contra Dengue/uso terapêutico , Diagnóstico Diferencial , Hemoptise/diagnóstico , Hemoptise/mortalidade , Hemoptise/terapia , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Dengue Grave/diagnóstico , Dengue Grave/mortalidade , Dengue Grave/terapia , Tomografia Computadorizada por Raios X
11.
Mycoses ; 60(4): 266-272, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28066933

RESUMO

To evaluate the performance of magnetic resonance imaging (MRI) compared to computed tomography (CT) in patients diagnosed with pulmonary mycosis. We prospectively included 21 patients diagnosed with pulmonary mycosis between January 2013 and October 2014. Inclusion criteria were presence of respiratory symptoms, histopathological diagnosis of mycosis and absence of mycosis treatment. Reviewers identified one predominant imaging pattern per patient: nodular, reticular or airspace pattern. Afterwards, all CT findings were analysed separately per lobe and compared to MRI. Nodular pattern was the most common found (CT: 76.20%; MRI: 80.96%), followed by airspace pattern (CT and MRI: 9.52%) and reticular (CT: 9.52%; MRI: 4.76%). Compared to CT, MRI performance varied according to radiological finding and pulmonary region. For nodules, MRI presented high sensitivity (100% [95% CI: 93.52-100]) and specificity (100% [95% CI: 92.00-100]). For bronchiectasis and septal thickening, there were poorer positive predictive values (33.33% [95% CI: 1.77-87.47]; and 83.33% [95% CI: 50.88-97.06] respectively). As specificity and negative predictive value had superior results than sensitivity and positive predictive value, rather than for diagnosis of this condition, MRI might be more considered for the follow-up of patients with pulmonary mycosis, an alternative to multiple radiation exposures with CT follow-up.


Assuntos
Pneumopatias Fúngicas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Pneumopatias Fúngicas/diagnóstico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade
12.
Lung ; 194(4): 501-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27300447

RESUMO

The aim of this review was to present the main aspects of pleural diseases seen with conventional and advanced magnetic resonance imaging (MRI) techniques. This modality is considered to be the gold standard for the evaluation of the pleural interface, characterization of complex pleural effusion, and identification of exudate and hemorrhage, as well as in the analysis of superior sulcus tumors, as it enables more accurate staging. The indication for MRI of the thorax in the identification of these conditions is increasing in comparison to computerized tomography, and it can also be used to support the diagnosis of pulmonary illnesses. This literature review describes the morphological and functional aspects of the main benign and malignant pleural diseases assessed with MRI, including mesothelioma, metastasis, lymphoma, fibroma, lipoma, endometriosis, asbestos-related pleural disease, empyema, textiloma, and splenosis.


Assuntos
Fibroma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Mesotelioma/diagnóstico por imagem , Neoplasias Pleurais/diagnóstico por imagem , Empiema/diagnóstico por imagem , Endometriose/diagnóstico por imagem , Feminino , Corpos Estranhos/diagnóstico por imagem , Humanos , Linfoma/diagnóstico por imagem , Masculino , Derrame Pleural/diagnóstico por imagem , Esplenose/diagnóstico por imagem , Tórax/diagnóstico por imagem
13.
Lung ; 193(5): 619-27, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26104489

RESUMO

Tuberous sclerosis complex (TSC) is an autosomal-dominant neurocutaneous disease with high phenotypic variability. The incidence is approximately one in 5000-10,000 births. TSC is characterized by widespread hamartomas and benign or rarely malignant neoplasms affecting various organs, most commonly the brain, skin, retinas, kidneys, heart, and lungs. The wide range of organs affected reflects the roles of TSC1 and TSC2 genes in the regulation of cell proliferation and differentiation. Clinical diagnostic criteria are important because genetic testing does not identify the mutation in up to 25% of patients. Imaging is pivotal, as it allows a presumptive diagnosis of TSC and definition of the extent of the disease. Common manifestations of TSC include cortical tubers, subependymal nodules, white matter abnormalities, retinal abnormalities, cardiac rhabdomyoma, lymphangioleiomyomatosis (LAM), renal angiomyolipoma, and skin lesions. Pulmonary involvement consists of LAM and, less commonly, multifocal micronodular pneumocyte hyperplasia (MMPH), which causes cystic and nodular diseases, respectively. Recent reports indicate that pulmonary LAM is found by computed tomography in up to 35% of the female patients with TSC. MMPH is rare and may be associated with LAM or, less frequently, occurs as an isolated pulmonary manifestation in women with TSC. Dyspnea and pneumothorax are common clinical presentations of LAM, whereas MMPH is usually asymptomatic. The aim of this review is to describe the main clinical, imaging, and pathological aspects of TSC, with a focus on pulmonary involvement.


Assuntos
Angiomiolipoma/etiologia , Carcinoma de Células Renais/etiologia , Neoplasias Renais/etiologia , Neoplasias Pulmonares/etiologia , Pulmão/patologia , Linfangioleiomiomatose/etiologia , Doenças do Sistema Nervoso/etiologia , Esclerose Tuberosa/complicações , Cistos/etiologia , Humanos , Hiperplasia/epidemiologia , Hiperplasia/patologia , Neoplasias Pulmonares/patologia , Linfangioleiomiomatose/patologia , Dermatopatias/etiologia
14.
Lung ; 192(2): 225-33, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24429586

RESUMO

Cocaine is the most commonly used illicit drug among patients presenting at hospital emergency departments and the most frequent cause of drug-related deaths reported by medical examiners. Various respiratory problems temporally associated with cocaine use have been reported. Acute and chronic uses also are responsible for lung complications, such as pulmonary edema, alveolar hemorrhage, pulmonary hypertension, organizing pneumonia, emphysema, barotrauma, infection, cancer, eosinophilic disease, and aspiration pneumonia. Although most imaging findings are nonspecific, they may raise suspicion of a cocaine-related etiology when considered together with patients' profiles and medical histories. This literature review describes cocaine-induced diseases with pulmonary involvement, with an emphasis on high-resolution chest computed tomographic findings and patterns.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/complicações , Pneumopatias/induzido quimicamente , Pneumopatias/diagnóstico por imagem , Pulmão/efeitos dos fármacos , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Feminino , Humanos , Pneumopatias/terapia , Masculino , Valor Preditivo dos Testes , Prognóstico , Adulto Jovem
15.
J Appl Clin Med Phys ; 14(4): 4215, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23835386

RESUMO

The purpose of this study was to identify the normal variance of emphysema index (EI) measured in examinations acquired with 64 multidetector-row computed tomography (64-MDCT). A longitudinal, noninterventional study was performed retrieving all patients in our institution who are currently registered in our lung nodule protocol. All patients with clinical, functional, or significant radiological changes were excluded. We assumed that EI should remain unchanged within a short period of time. We reviewed 475 MDCTs in order to select 50 clinically stable patients who had two sequential chest MDCTs performed within a time interval of less than three months, and who presented at least one lung free of abnormalities but emphysema. CT densitovolumetry was used to calculate EI with thresholds set at -950 Hounsfield units (HUs) (EI-950) and -970 HUs (EI-970); on both studies from each patient. We observed the variation of total lung volume (TLV), mean lung density (MDL), and EI for measurements at the baseline and at follow-up scans. Differences observed between baseline and follow-up measurements were: TLV µ= 149 ml; IC = µ +1.96 (133); EI-950 µ = 0.02%; p 95 = 0.89%; EI-970 µ = 0.04%; p 95 = 0.23% and MLD µ = 15 HU; IC = µ +1.96 (18). The correlations obtained were the following: TLV r = 0.96, EI-950 r = 0.79, EI-970 r = 0.85. Accepting that emphysema would remain unchanged within three months on stable patients, differences of less than 0.89% for EI-950 and of less than 0.23% for EI-970 are within the variance of the method.


Assuntos
Tomografia Computadorizada Multidetectores , Enfisema Pulmonar/diagnóstico por imagem , Idoso , Análise de Variância , Feminino , Humanos , Imageamento Tridimensional , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/estatística & dados numéricos , Estudos Retrospectivos
16.
Sci Rep ; 13(1): 21352, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049444

RESUMO

We introduce a novel technique for designing color filter metasurfaces using a data-driven approach based on deep learning. Our innovative approach employs inverse design principles to identify highly efficient designs that outperform all the configurations in the dataset, which consists of 585 distinct geometries solely. By combining Multi-Valued Artificial Neural Networks and back-propagation optimization, we overcome the limitations of previous approaches, such as poor performance due to extrapolation and undesired local minima. Consequently, we successfully create reliable and highly efficient configurations for metasurface color filters capable of producing exceptionally vivid colors that go beyond the sRGB gamut. Furthermore, our deep learning technique can be extended to design various pixellated metasurface configurations with different functionalities.

17.
AJR Am J Roentgenol ; 199(3): W331-4, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22915423

RESUMO

OBJECTIVE: The aim of this study was to show the usefulness of chemical-shift MRI in the diagnosis of intranodular fat in seven patients with pulmonary hamartomas and indeterminate CT findings. CONCLUSION: In the setting of chemical-shift MRI, the average nodule signal intensity index of pulmonary hamartomas was 45.3% (SD = 25.5%). The correlation between average nodule signal intensity and CT attenuation in Hounsfield units was -0.94. Chemical-shift MRI could be an important tool for the detection of fat in pulmonary hamartomas with inconclusive CT findings.


Assuntos
Tecido Adiposo/patologia , Hamartoma/diagnóstico , Pneumopatias/diagnóstico , Imageamento por Ressonância Magnética , Idoso , Hamartoma/diagnóstico por imagem , Hamartoma/patologia , Humanos , Pneumopatias/diagnóstico por imagem , Pneumopatias/patologia , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
18.
Radiographics ; 32(1): 71-84, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22236894

RESUMO

Paracoccidioidomycosis (PCM) is the most common systemic mycosis in Latin America. Although most cases occur in developing countries, recent immigration patterns and an increase in travel have led to a growing number of PCM cases in the United States and Europe. PCM is caused by the dimorphic fungus Paracoccidioides brasiliensis, and the chronic form may progress to severe pulmonary involvement. Several radiologic patterns have been described for pulmonary PCM, including linear and reticular opacities, variable-sized nodules, patchy ill-defined opacities, airspace consolidation, and cavitary lesions. Fibrosis and paracicatricial emphysema are common associated findings. Chest computed tomography (CT) is the method of choice for evaluating pulmonary PCM, with the most common CT findings being ground-glass attenuation, consolidation, small or large nodules, masses, cavitations, interlobular septal thickening, emphysema, and fibrotic lesions. PCM is also an important cause of the "reversed halo" sign at high-resolution CT and should be considered in the differential diagnosis. Awareness of the multiple radiologic manifestations of PCM as well as its epidemiologic and clinical characteristics may permit early diagnosis and initiation of specific treatment, thereby reducing associated morbidity and mortality.


Assuntos
Pneumopatias Fúngicas/diagnóstico por imagem , Paracoccidioidomicose/diagnóstico por imagem , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos
19.
PLoS One ; 17(5): e0268538, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35580093

RESUMO

The outbreak of COVID-19 has led to there being a worldwide socio-economic crisis, with major impacts on developing countries. Understanding the dynamics of the disease and its driving factors, on a small spatial scale, might support strategies to control infections. This paper explores the impact of the COVID-19 on neighborhoods of Recife, Brazil, for which we examine a set of drivers that combines socio-economic factors and the presence of non-stop services. A three-stage methodology was conducted by conducting a statistical and spatial analysis, including clusters and regression models. COVID-19 data were investigated concerning ten dates between April and July 2020. Hotspots of the most affected regions and their determinant effects were highlighted. We have identified that clusters of confirmed cases were carried from a well-developed neighborhood to socially deprived areas, along with the emergence of hotspots of the case-fatality rate. The influence of age-groups, income, level of education, and the access to essential services on the spread of COVID-19 was also verified. The recognition of variables that influence the spatial spread of the disease becomes vital for pinpointing the most vulnerable areas. Consequently, specific prevention actions can be developed for these places, especially in heterogeneous cities.


Assuntos
COVID-19 , Brasil/epidemiologia , COVID-19/epidemiologia , Humanos , Pandemias , Características de Residência , SARS-CoV-2
20.
ACS Appl Bio Mater ; 5(3): 1267-1272, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35168328

RESUMO

The eradication of microorganisms from high traffic surfaces to prevent either viral or bacterial infections represents an urgent need, mainly in the scope of the present pandemic scenario. In this context, this work explores the dual functionality of titanium-copper thin films as pressure elements with antimicrobial properties, aiming for the implementation of touch and sensing capabilities in high traffic surfaces. Copper was employed as the antibacterial agent within a titanium matrix. The film's geometry and deposition parameters were varied in order to optimize antimicrobial and piezoresistive response. A considerable antimicrobial response has been obtained, increasing the copper amount (from 23 to 63 at. %) in the titanium matrix, leading to an outstanding 8 log10 CFU bacterial reduction in the case of Escherichia coli. Moreover, for the same amount of copper, the piezoresistive sensibility of the thin films increases up to a maximum gauge factor of 5.18 ± 0.09, which indicates an adequate electromechanical behavior for sensing applications. Our findings demonstrate the best combined antimicrobial and piezoresistive characteristics for the films with a Cu content of 63 at. %, indicating a potential use of these films for electromechanical sensor applications.


Assuntos
Anti-Infecciosos , Titânio , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Cobre/farmacologia , Escherichia coli
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