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1.
ISA Trans ; 113: 28-38, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32646591

RESUMO

Efficiency and robustness in remaining useful life (RUL) prediction are crucial in system health monitoring. Thus, the internal logic computation of a Deep LSTM model for RUL prediction is mainly shaped and evaluated over a training data-set and its performance examined on a testing data-set. This paper proposes a framework for testing robustness of deep Long Short Term Memory (LSTM) architecture for remaining useful life prediction that enables to gain confidence in the trained LSTM model for RUL prediction and ensures better quality. The resiliency of proposed Deep LSTM networks for RUL estimation using stress functions is first checked then the effect of the stress on model performance is analyzed. A comparison between the performance of the constructed mutant fuzzed Deep LSTM networks and the original Deep LSTM model for RUL prediction is provided to determine the quality of the RUL prediction model. Furthermore, the main purpose of this paper is to determine to what extent Deep LSTM models in the neighborhood of the trained LSTM model still have high test accuracy and quality scoring. Thus, the use of φ-stress operators shows that we could build stable and data-independent Deep LSTM models for RUL prediction. Finally, the proposed framework is validated using the Commercial Modular Aero Propulsion System Simulation (C-MAPSS) data-set.

2.
PLoS One ; 11(9): e0161751, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27644093

RESUMO

Orange (Citrus sinensis) and grapefruit (Citrus paradise) peels were used as a source of pectin, which was extracted under different conditions. The peels are used under two states: fresh and residual (after essential oil extraction). Organic acid (citric acid) and mineral acid (sulfuric acid) were used in the pectin extraction. The aim of this study is the evaluation the effect of extraction conditions on pectin yield, degree of esterification "DE" and on molecular weight "Mw". Results showed that the pectin yield was higher using the residual peels. Moreover, both peels allow the obtainment of a high methoxyl pectin with DE >50%. The molecular weight was calculated using Mark-Houwink-Sakurada equation which describes its relationship with intrinsic viscosity. This later was determined using four equations; Huggins equation, kramer, Schulz-Blaschke and Martin equation. The molecular weight varied from 1.538 x1005 to 2.47x1005 g/mol for grapefruit pectin and from 1.639 x1005 to 2.471 x1005 g/mol for orange pectin.


Assuntos
Citrus paradisi/química , Citrus sinensis/química , Pectinas/química , Extratos Vegetais/química , Ácido Cítrico/química , Esterificação , Frutas/química , Pectinas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ácidos Sulfúricos/química , Viscosidade
3.
Tunis Med ; 83(12): 725-30, 2005 Dec.
Artigo em Francês | MEDLINE | ID: mdl-16450938

RESUMO

Lung cancer is the world's first cause of death by cancer. Locally advanced and metastatic non small cell cancers represent 2/3rd of cases at diagnosis and are of worst prognosis. We conducted a retrospective study of 202 patients to investigate the effect of chemotherapy on survival and quality of life. 95 patients received chemotherapy with VP16-CDDP (88%) or Gemcitabin-CDDP. Improvement survival was observed in the chemotherapy group: 8 month IC 95% [6.6-9.3] 4 month IC 95% [3.1-4.9] in the control group. Chemotherapy also had a good perfect on the quality of life with improvement of performance status, symptoms and need of analgesic. However although significant, the role of chemotherapy in NSCLC remains modest and new therapeutic approaches are needed including prevention and early detection which are probably more effective and cheaper.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida
4.
Tunis Med ; 82(8): 735-41, 2004 Aug.
Artigo em Francês | MEDLINE | ID: mdl-15532768

RESUMO

The incidence of chronic obstructive pulmonary disease (COPD) is increasing particularly in developing countries. Their prognosis depend on several factors in particular the one second forced expiratory volume (FEV1) decline. To study FEV1 decline speed and factors affecting it, we carried out a retrospective study of 160 cases of COPD in stable state and heaving at least two FEV1 measures at 6 months of interval in the minimum and. The middle age was 63 +/- 12 yr, 52% was former smokers and 46% current smokers, with middle of 50 +/- 27 pack-yr. The FEV1 decline was calculated by linear regression models. The decline average in FEV1 with time was 72 +/- 55 ml/yr. Absolute value was higher than 30 ml/yr therefore more accelerated than general population in 79% of cases. We confirmed by multivariate analysis that age and smoking habit and increased the FEV1 decline. However this last correlated with FEV1% predicted. We concluded that the decline of FEV1 is higher in COPD that in the general population and slowing it needs smoking stop.


Assuntos
Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Ventilação Pulmonar , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos
5.
Rev Med Suisse Romande ; 124(7): 427-9, 2004 Jul.
Artigo em Francês | MEDLINE | ID: mdl-15379167

RESUMO

The sleep apnea syndrome (SAS) and hypothyroidism have several common signs. This similarity creates a significant risk of undiagnosed hypothyroidism during the SAS. We studied the interest of thyroid function testing at patients suspected of having SAS. 201 consecutive patients, having a suspicion of SAS without history of hypothyroidism, underwent polysomnography (PSG) and biochemical thyroid testing. 91 patients (47%) had a SAS. Three patients among them (1.5% of patients undergoing PSG or 3.3% of those having a SAS) had previously undiagnosed hypothyroidism. These three patients have been treated by thyroxine. After euthyroidism was obtained by the treatment, SAS disappeared in 2 patients. The prevalence of the hypothyroidism in patients suspected of having SAS is not different from the one in the general population. However it is greater in patients with SAS. So we can conclude that biochemical screening for hypothyroidism is indicated only in case of proven SAS, in order to distinguish between a primary and a secondary origin.


Assuntos
Hipotireoidismo/complicações , Hipotireoidismo/diagnóstico , Síndromes da Apneia do Sono/etiologia , Testes de Função Tireóidea , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
6.
Tunis Med ; 82(9): 843-8, 2004 Sep.
Artigo em Francês | MEDLINE | ID: mdl-15693478

RESUMO

Prognostic factors have a pivotal role in clinical oncology. They are helpful in the selection of treatment, provide insights into the disease process and the therapeutic response. The number of possibly useful prognostic factors in the lung cancer is large. This study attempts to observe the survival of non small cell lung cancer (NSCLC) and to find prognostic factors and other variables potentially associated with outcome of lung cancer. It's a retrospective study based on 211 patients with NSCLC. Median survival was 6 months with 95% confidence interval: [4.2 - 7.8]. Overall 3 and 5 year survival were respectively 8.3% and 5.2%. Various Prognostic factors have been identified through univariate (Kaplan-Meier) then multivariate (Cox) analyses. In addition to the clinical factors such as age, disease extent and performance status, other variables were found of significant prognostic value, like pretherapeutic leukocyte level. Survival was significantly improved with surgery, radiation and also with chemotherapy, mainly in advanced stage (IIIB and IV).


Assuntos
Carcinoma Pulmonar de Células não Pequenas/mortalidade , Neoplasias Pulmonares/mortalidade , Adenocarcinoma/patologia , Fatores Etários , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma de Células Escamosas/patologia , Feminino , Seguimentos , Humanos , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
7.
Tunis Med ; 81(10): 828-31, 2003 Oct.
Artigo em Francês | MEDLINE | ID: mdl-17722802

RESUMO

We report a case of pulmonary infarction in a 72-year-old woman who was hospitalised for hemoptysis, chest pain and weight and coin a lesion in the loss periphery of the left lower lobe. Camputed tomography of the chest demonstrated a sub pleural solitary nodule with spicular radiation. Video-assisted thoracoscopic surgery was performed to obtain a histological diagnosis. Thoracoscopic examination showed a lesion that evoked chronic abscess. Histological examination confirmed an ischemic infarction. This is the second case of pseudotumor due to pulmonary infarction that was diagnosed by video-assisted thoracoscopic resection.


Assuntos
Embolia Pulmonar/complicações , Nódulo Pulmonar Solitário/diagnóstico , Cirurgia Torácica Vídeoassistida , Idoso , Feminino , Humanos
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