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1.
J Imaging ; 10(9)2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39330436

RESUMO

Methods based on deep learning have achieved great success in the field of video action recognition. When these methods are applied to real-world scenarios that require fine-grained analysis of actions, such as being tested on a tea ceremony, limitations may arise. To promote the development of fine-grained action recognition, a fine-grained video action dataset is constructed by collecting videos of tea ceremony actions. This dataset includes 2745 video clips. By using a hierarchical fine-grained action classification approach, these clips are divided into 9 basic action classes and 31 fine-grained action subclasses. To better establish a fine-grained temporal model for tea ceremony actions, a method named TSM-ConvNeXt is proposed that integrates a TSM into the high-performance convolutional neural network ConvNeXt. Compared to a baseline method using ResNet50, the experimental performance of TSM-ConvNeXt is improved by 7.31%. Furthermore, compared with the state-of-the-art methods for action recognition on the FineTea and Diving48 datasets, the proposed approach achieves the best experimental results. The FineTea dataset is publicly available.

2.
Sci Rep ; 14(1): 19144, 2024 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160216

RESUMO

Peripheral Capillary Oxygen Saturation (SpO2) has received increasing attention during the COVID-19 pandemic. Clinical investigations have demonstrated that individuals afflicted with COVID-19 exhibit notably reduced levels of SpO2 before the deterioration of their health status. To cost-effectively enable individuals to monitor their SpO2, this paper proposes a novel neural network model named "ITSCAN" based on Temporal Shift Module. Benefiting from the widespread use of smartphones, this model can assess an individual's SpO2 in real time, utilizing standard facial video footage, with a temporal granularity of seconds. The model is interweaved by two distinct branches: the motion branch, responsible for extracting spatiotemporal data features and the appearance branch, focusing on the correlation between feature channels and the location information of feature map using coordinate attention mechanisms. Accordingly, the SpO2 estimator generates the corresponding SpO2 value. This paper summarizes for the first time 5 loss functions commonly used in the SpO2 estimation model. Subsequently, a novel loss function has been contributed through the examination of various combinations and careful selection of hyperparameters. Comprehensive ablation experiments analyze the independent impact of each module on the overall model performance. Finally, the experimental results based on the public dataset (VIPL-HR) show that our model has obvious advantages in MAE (1.10%) and RMSE (1.19%) compared with related work, which implies more accuracy of the proposed method to contribute to public health.


Assuntos
COVID-19 , Saturação de Oxigênio , Fotopletismografia , Humanos , Fotopletismografia/métodos , COVID-19/sangue , COVID-19/diagnóstico , Redes Neurais de Computação , Oximetria/métodos , Oxigênio/sangue , SARS-CoV-2/isolamento & purificação , Monitorização Fisiológica/métodos , Smartphone
3.
Brain Sci ; 13(12)2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38137172

RESUMO

Counterfactual conditionals posit hypothetical scenarios in which antecedent events contradict reality. This study examined whether and how the processing difficulty of Chinese counterfactual conditionals (yaobushi, equivalent to if it had not been for in English) can be affected by the length of temporal shifts of the events across clauses and the likelihood of the antecedent occurrence. Participants read Chinese counterfactuals that contained either long (e.g., qunian-xianzai [last year-right now]) or short temporal shifts (e.g., zuotian-xianzai [yesterday-right now]) within highly likely (e.g., sign up for school activity) or less likely contexts (e.g., sign up for Arctic scientific research). ERP results revealed a significant N400 interaction between the temporal shift length and antecedent likelihood on the temporal indicators in the consequent and the sentence-ending verbs. Specifically, the less likely events elicited larger negativity than highly likely events with short temporal shifts on the temporal indicator. On the sentence-ending word, the long temporal shift elicited enlarged negativity than the short temporal shift when the antecedent was highly likely. These findings have two key implications regarding the interplay of implied causality and falsity constraints during counterfactual comprehension. First, salient falsity constraints can override effects of causal coherence on processing. Second, greater negativity for unlikely antecedents suggests that counterfactual markers concurrently activate factual and hypothetical representations.

4.
Viruses ; 15(8)2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37632013

RESUMO

Respiratory syncytial virus is among the most common causes of respiratory infections. Typically, this viral infection has a seasonality during the cold months but with the SARS-CoV-2 pandemic this has been considerably modified. Here, we studied the epidemiology of this virus in university hospitals of Marseille, South of France, over the period 2020 to 2023. We tested in our laboratory from July 2020 to October 2021 16,516 nasopharyngeal swabs from 16,468 patients for RSV infection using different qPCR assays. We then analyzed data from previous and subsequent winters (from 2018 to 2023) and previous summers (from 2015 to 2021). A total of 676 patients were RSV-positive; their mean age was 3 years and 91 were under 5 years of age. We observed a delay of 4 months of the RSV epidemic's onset compared to other years with an epidemic that peaked in March 2021. We had significantly more RSV-positive cases during summer 2021 compared to previous summers, whereas the incidence of RSV infections was not significantly higher during winter 2022 versus previous winters. Moreover, 494 patients were diagnosed as RSV-positive in the emergency unit and 181 were subsequently hospitalized, and 34 patients were diagnosed RSV-positive while already in the intensive care unit. Over all the study periods, 38 patients diagnosed as RSV-positive died, the majority of whom (23/28) were over 65 years of age. These data show an atypical evolution of the incidence of RSV infections in our city and is another example of the unpredictability of infectious disease epidemiology.


Assuntos
COVID-19 , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Humanos , Pré-Escolar , COVID-19/epidemiologia , SARS-CoV-2 , Infecções por Vírus Respiratório Sincicial/epidemiologia , Pandemias , França/epidemiologia
5.
Neuroimage ; 254: 119136, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35346840

RESUMO

Hemodynamic cardiac and respiratory-cycle fluctuations are a source of unwanted non-neuronal signal components, often called physiologic noise, in resting state (rs-) fMRI studies. Here, we use image-based retrospective correction of physiological motion (RETROICOR) with externally measured physiologic signals to investigate cardiac and respiratory hemodynamic phase functions reflected in rs-fMRI data. We find that the cardiac phase function is time shifted locally, while the respiratory phase function is described as single, fixed phase form across the brain. In light of these findings, we propose an update to Physiologic EStimation by Temporal ICA (PESTICA), our publically available software package that estimates physiologic signals when external physiologic measures are not available. This update incorporates: 1) auto-selection of slicewise physiologic regressors and generation of physiologic fixed phase regressors with total slices/TR sampling rate, 2) Fourier series expansion of the cardiac fixed phase regressor to account for time delayed cardiac noise 3) removal of cardiac and respiratory noise in imaging data. We compare the efficacy of the updated method to RETROICOR.


Assuntos
Artefatos , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
6.
Environ Sci Technol ; 56(10): 6056-6068, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34668380

RESUMO

Zwitterionic, cationic, and anionic per- and polyfluoroalkyl substances (PFAS) are increasingly reported in terrestrial and aquatic environments, but their inputs to agricultural lands are not fully understood. Here, we characterized PFAS in 47 organic waste products (OWP) applied in agricultural fields of France, including historical and recent materials. Overall, 160 PFAS from 42 classes were detected from target screening and homologue-based nontarget screening. Target PFAS were low in agriculture-derived wastes such as pig slurry, poultry manure, or dairy cattle manure (median ∑46PFAS: 0.66 µg/kg dry matter). Higher PFAS levels were reported in urban and industrial wastes, paper mill sludge, sewage sludge, or residual household waste composts (median ∑46PFAS: 220 µg/kg). Historical municipal biosolids and composts (1976-1998) were dominated by perfluorooctanesulfonate (PFOS), N-ethyl perfluorooctanesulfonamido acetic acid (EtFOSAA), and cationic and zwitterionic electrochemical fluorination precursors to PFOS. Contemporaneous urban OWP (2009-2017) were rather dominated by zwitterionic fluorotelomers, which represented on average 55% of ∑160PFAS (max: 97%). The fluorotelomer sulfonamidopropyl betaines (X:2 FTSA-PrB, median: 110 µg/kg, max: 1300 µg/kg) were the emerging class with the highest occurrence and prevalence in contemporary urban OWP. They were also detected as early as 1985. The study informs for the first time that urban sludges and composts can be a significant repository of zwitterionic and cationic PFAS.


Assuntos
Compostagem , Fluorocarbonos , Animais , Biossólidos , Bovinos , Esterco , Esgotos/química , Suínos , Resíduos
7.
Acta Otolaryngol ; 141(6): 603-607, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34028329

RESUMO

BACKGROUND: Although stapedotomy is effective for patients with clinical otosclerosis, the time of hearing stabilization has not yet been consistent. OBJECTIVE: To investigate the relationships between post-operative follow-up times, hearing outcomes, and threshold shift after stapedotomy. MATERIALS AND METHODS: Fifty-five patients with clinical otosclerosis that underwent stapedotomy were retrospectively studied. Pure tone audiometry tests were conducted within the first month (short-term) and within 1 year (mid-term) postoperatively. Data were analyzed for two rounds of audiometry tests at different postoperative follow-up times. RESULTS: Air conduction (AC) and bone conduction (BC) were significantly correlated with preoperative hearing levels (p<.01). AC, BC, and air bone gap (ABG) significantly improved at the short-term (p<.001) and continued to improve at the mid-term (p<.01). The success rate of surgery increased from 87% at short-term to 98% at mid-term. Less than 1/3 of cases encountered BC deterioration at short-term, whereas most improved at mid-term. CONCLUSIONS: Hearing results showed a trend of improvement between short-term and mid-term follow-ups after stapedotomy. AC, ABG, and success rate displayed significant improvement several months postoperatively. BC deterioration occurred in less than 30% of patients at short-term. The recovery of BC at 4 kHz was later than that of low frequencies.


Assuntos
Perda Auditiva/cirurgia , Otosclerose/cirurgia , Cirurgia do Estribo , Adulto , Audiometria de Tons Puros , Condução Óssea , Ossículos da Orelha/anatomia & histologia , Feminino , Seguimentos , Audição , Perda Auditiva/etiologia , Perda Auditiva Condutiva/etiologia , Perda Auditiva Condutiva/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Otosclerose/complicações , Otosclerose/patologia , Período Pós-Operatório , Estudos Retrospectivos , Resultado do Tratamento
8.
Int J Psychophysiol ; 147: 93-99, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31760105

RESUMO

Fear acquisition manifests in the development of conditioned fear responses (CRs), whereas a decrement in CRs as a consequence of unconditioned stimulus (UCS) omission is referred to as extinction learning. Time windows for CR scoring in physiological readouts are subject to discussion, especially regarding the subdivision of skin conductance responses (SCRs) into first- (FIR) and second-interval responses (SIR). However, distinct temporal CR trajectories within or across measures may reflect specific characteristics of the underlying associative processes. In this study, 41 participants underwent fear acquisition and extinction, while SCRs and pupillary responses were recorded and separated into different time bins to explore the temporal dynamics of CRs across both learning phases. For SCRs, we observed a shift from early (FIR) to late (SIR) time intervals during fear acquisition most likely reflecting subsequent learning processes, in which CS-UCS associations and their relative timing are formed. During extinction, only the FIR exhibited a CR decline and was thus able to track the learning progress. These results indicate that conditioned SCRs follow a dynamic temporal pattern that may be related to different learning dimensions. By contrast, pupillary CRs were generally better captured by a late pupillary response component, suggesting a rather stable temporal CR pattern for the pupil in both learning phases. Our findings underscore the importance of specifying CR quantification for different physiological readouts when evaluating learning performance in the context of fear acquisition and extinction and may motivate further investigation of time-specific CR patterns and their relation to specific associative dimensions.


Assuntos
Condicionamento Clássico/fisiologia , Extinção Psicológica/fisiologia , Medo/fisiologia , Resposta Galvânica da Pele/fisiologia , Pupila/fisiologia , Adulto , Medições dos Movimentos Oculares , Feminino , Humanos , Masculino , Adulto Jovem
9.
J Magn Reson Imaging ; 47(6): 1616-1625, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28963852

RESUMO

BACKGROUND: Glioma grade along with patient's age and general health are used for treatment planning and prognosis. PURPOSE: To characterize and quantify the spontaneous blood oxygen level-dependent (BOLD) fluctuations in gliomas using measures based on T2*-weighted signal time-series and to distinguish between high- and low-grade gliomas. STUDY TYPE: Retrospective. SUBJECTS: Twenty-one patients with high-grade and 13 patients with low-grade gliomas confirmed on histology were investigated. FIELD STRENGTH/SEQUENCE: Dynamic T2*-weighted (multislice single-shot echo-planar-imaging) magnetic resonance imaging (MRI) was performed on a 3T system with an 8-element receive-only head coil to measure the BOLD fluctuations. In addition, a dynamic T1 -weighted (3D fast field echo) dynamic contrast-enhanced (DCE) perfusion scan was performed. ASSESSMENT: Three BOLD measures were determined: the temporal shift (TS), amplitude of low frequency fluctuations (ALFF), and regional homogeneity (ReHo). DCE perfusion-based cerebral blood volume (CBV) and time-to-peak (TTP) maps were concurrently evaluated for comparison. STATISTICAL TESTS: An analysis-of-variance test was first used. When the test appeared significant, post-hoc analysis was performed using analysis-of-covariance with age as covariate. Logistic regression and receiver-operator characteristic curve analysis were also performed. RESULTS: TS was significantly advanced in high-grade gliomas compared to the contralateral cortex (P = 0.01) and low-grade gliomas (P = 0.009). In high-grade gliomas, ALFF and CBV were significantly higher than the contralateral cortex (P = 0.041 and P = 0.008, respectively) and low-grade gliomas (P = 0.036 and P = 0.01, respectively). ReHo and TTP did not show significant differences between high- and low-grade gliomas (P = 0.46 and P = 0.42, respectively). The area-under-curve was above 0.7 only for the TS, ALFF, and CBV measures. DATA CONCLUSION: Advanced and amplified hemodynamic fluctuations manifest in high-grade gliomas, but not in low-grade gliomas, and can be assessed using BOLD measures. Preliminary results showed that quantification of spontaneous fluctuations has potential for hemodynamic characterization of gliomas and distinguishing between high- and low-grade gliomas. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2018;47:1616-1625.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Imagem Ecoplanar , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adolescente , Adulto , Idoso , Circulação Cerebrovascular , Meios de Contraste/química , Reações Falso-Positivas , Feminino , Hemodinâmica , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Perfusão , Prognóstico , Curva ROC , Estudos Retrospectivos , Adulto Jovem
10.
Parasit Vectors ; 10(1): 102, 2017 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-28228159

RESUMO

BACKGROUND: Aedes albopictus and Culex pipiens larvae reared in the same breeding site compete for resources, with an asymmetrical outcome that disadvantages only the latter species. The impact of these interactions on the overall ecology of these two species has not yet been assessed in the natural environment. In the present study, the temporal patterns of adult female mosquitoes from both species were analysed in north-eastern Italy, and substantial temporal shifts between abundance curves of Cx. pipiens and Ae. albopictus were observed in several sites. To understand which factors can drive the observed temporal shifts, we developed a mechanistic model that takes explicitly into account the effect of temperature on the development and survival of all mosquito stages. We also included into the model the effect of asymmetric interspecific competition, by adding a mortality term for Cx. pipiens larvae proportional to the larval abundance of Ae. albopictus within the same breeding site. Model calibration was performed through a Markov Chain Monte Carlo approach using weekly capture data collected in our study sites during 2014 and 2015. RESULTS: In almost half of observation sites, temporal shifts were due to competition, with an early decline of Cx. pipiens caused by the concurrent rise in abundance of its competitor, and this effect was enhanced by higher abundance of both species. We estimate that competition may reduce Cx. pipiens abundance in some sites by up to about 70%. However, in some cases temporal shifts can also be explained in the absence of competition between species resulting from a "temporal niche" effect, when the optimal fitness to environmental conditions for the two species are reached at different times of the year. CONCLUSIONS: Our findings demonstrate the importance of considering ecological interactions and, in particular, competition between mosquito species in temperate climates, with important implications for risk assessment of mosquito transmitted pathogens, as well as the implementation of effective control measures.


Assuntos
Aedes/fisiologia , Culex/fisiologia , Animais , Comportamento Competitivo , Feminino , Modelos Biológicos , Dinâmica Populacional , Especificidade da Espécie , Fatores de Tempo
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