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1.
Comput Intell Neurosci ; 2022: 8148586, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275964

RESUMO

Butterfly optimization algorithm (BOA) is a new swarm intelligence algorithm mimicking the behaviors of butterflies. However, there is still much room for improvement. In order to enhance the convergence speed and accuracy of the BOA, we present an improved algorithm SCLBOA based on SIBOA, which incorporates a logical mapping and a Lévy flight mechanism. The logical chaotic map is used for population initialization, and then the Lévy flight mechanism is integrated into the SCLBOA algorithm. To evaluate the performance of the SCLBOA, we conducted many experiments on standard test functions. The simulation results suggest that the SCLBOA is capable of high-precision optimization, fast convergence, and effective global optimization, all of which show that our method outperforms other methods in solving mathematical optimization problems. Finally, the BP network is optimized according to the SCLBOA (SCLBOA-BP) to further verify the availability of the algorithm. Simulation experiments prove the practicability of this method by building a Boston housing price prediction model for training.


Assuntos
Borboletas , Animais , Algoritmos , Simulação por Computador , Resolução de Problemas
2.
Sensors (Basel) ; 22(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408212

RESUMO

Industrial control systems (ICS) are applied in many fields. Due to the development of cloud computing, artificial intelligence, and big data analysis inducing more cyberattacks, ICS always suffers from the risks. If the risks occur during system operations, corporate capital is endangered. It is crucial to assess the security of ICS dynamically. This paper proposes a dynamic assessment framework for industrial control system security (DAF-ICSS) based on machine learning and takes an industrial robot system as an example. The framework conducts security assessment from qualitative and quantitative perspectives, combining three assessment phases: static identification, dynamic monitoring, and security assessment. During the evaluation, we propose a weighted Hidden Markov Model (W-HMM) to dynamically establish the system's security model with the algorithm of Baum-Welch. To verify the effectiveness of DAF-ICSS, we have compared it with two assessment methods to assess industrial robot security. The comparison result shows that the proposed DAF-ICSS can provide a more accurate assessment. The assessment reflects the system's security state in a timely and intuitive manner. In addition, it can be used to analyze the security impact caused by the unknown types of ICS attacks since it infers the security state based on the explicit state of the system.


Assuntos
Inteligência Artificial , Computação em Nuvem , Algoritmos , Big Data , Aprendizado de Máquina
3.
Heart Lung Circ ; 23(12): 1202-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25224460

RESUMO

OBJECTIVE AND DESIGN: Our study aimed to determine the effect of mild hypothermia (MHT) on the expression of toll-like receptor 2 (TLR2) in lung tissue with acute lung injury. The animals were randomly divided into control, model and mild hypothermia groups. METHODS: A total of 40 rats was used in the study. Acute lung injury was induced by lipopolysaccharide and MHT was maintained at 32.5∼33.0 °C using body surface ice-bag placement combined with animal thermostat system. The ratio of PaO2/FiO2 was recorded. The mRNA and protein expressions of TLR2 were measured by real-time polymerase chain reaction and western blotting respectively. Moreover, enzyme linked immunosorbent assay were used for the quantification of TNF-α. RESULTS: The ratio of PaO2/FiO2 was increased by MHT. TLR2 and TNF-α were increased in the rat lung 1h and 8h in the rats with acute lung injury while they were significantly decreased by MHT. Histological examination revealed that MHT alleviated the degree of inflammation. CONCLUSION: Our study suggested that MHT might improve the lung function by inhibiting the inflammation via down-regulating the expressions of TLR2 in the acute injury lung tissues.


Assuntos
Lesão Pulmonar Aguda , Regulação da Expressão Gênica , Hipotermia Induzida , Pulmão/metabolismo , Receptor 2 Toll-Like/biossíntese , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/terapia , Animais , Modelos Animais de Doenças , Inflamação/metabolismo , Inflamação/patologia , Inflamação/terapia , Pulmão/patologia , Masculino , Ratos , Fator de Necrose Tumoral alfa/biossíntese
4.
Artigo em Chinês | MEDLINE | ID: mdl-25065207

RESUMO

OBJECTIVE: To investigate the expression of hepatic Toll-like receptor 1 (TLR1), TLR2 and TLR6 on mice with Schistosoma japonicum infection. METHODS: Fifty BALB/c mice were infected with 20 +/- 3 S. japonicum cercariae through abdominal skin. At 6 weeks post-infection, the mice (n = 10) in treatment group were administered intragastrically with praziquantel [250 microg/(g x d)] for 3 d. The livers of mice (n = 10) were collected at pre-infection and 5, 6, 8 and 12 weeks post-infection, and then the mRNA expression levels of hepatic TLR1, TLR2, TLR6 gene were detected with reverse transfer PCR. Hepatic TLR2, TLR6 protein levels were detected by immunohistochemical staining. RESULTS: The mRNA levels of TLR1, TLR2, and TLR6 on 5, 6, 8 and 12 weeks post infection were significantly higher than that of uninfected mice. After praziquantel treatment, the mRNA level of TLR2 and TLR6 in murine liver of treatment group was lower than that of infection group, but the level of TLR1 mRNA had no obvious change. Furthermore, immunohistochemistry results revealed that the expression of TLR2 and TLR6 proteins in murine liver was up-regulated at 5, 6, 8 and 12 weeks post-infection. After praziquantel treatment, the percentage of TLR2 positive area in liver of infected mice without and with praziquantel treatment were (44.2 +/- 4.3)%, (8.8 +/- 3.1)%, respectively, and TLR2 protein level was considerably down-regulated (P < 0.01). The percentage of TLR6 positive area in liver of infected mice without and with praziquantel treatment was (48.4 +/- 5.4)%, (37.4 +/- 3.5)%, respectively, and TLR6 level decreased slightly (P < 0.05). CONCLUSION: The expression level of TRL2 and TLR6 in murine liver increases after Schistosoma japonicum infection. While compared with TLR2, the role of TLR6 in this progress is a weaker one.


Assuntos
Regulação da Expressão Gênica , Fígado , Esquistossomose Japônica/metabolismo , Receptor 2 Toll-Like/genética , Receptor 6 Toll-Like/genética , Animais , Cercárias , Camundongos , Camundongos Endogâmicos BALB C , Praziquantel , RNA Mensageiro
5.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 23(4): 236-8, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21473828

RESUMO

OBJECTIVE: To investigate the effect of hypothermia (HT) on the concentration of surfactant protein A (SP-A) during lipopolysaccharide (LPS) induced acute lung injury (ALI) in rats. METHODS: Forty male Wistar rats were randomly divided into three groups. The ALI model was reproduced by LPS intratracheal instillation; only saline was instilled intratracheally for control group. Rats in both model group and control group were sacrificed respectively at 1 hour and 8 hours (each n=8). In HT group the body temperature was lowered to 32.5-33.0 centigrade 1 hour after LPS instillation, and 8 rats were sacrificed at 8 hours. The arterial blood gas was determined in all the groups before and 1 hour and 8 hours after instillation of saline or LPS, and the oxygenation index (PaO(2)/FiO(2)) was calculated. The concentration of SP-A in bronchoalveolar lavage fluid (BALF) was determined by enzyme linked immunosorbent assay. The morphological changes in lung tissue of rats were observed under light microscope. RESULTS: At 1 hour after intratracheal instillation of LPS, the PaO(2)/FiO(2) of each group reached the diagnostic criterion of ALI. Compared with control 1 hour group, the SP-A (µg/L) in BALF of model 1 hour group was decreased (53.27±1.95 vs. 74.81±6.55, P<0.01); the SP-A in model 8 hour group and HT 8 hour group (4.35±2.76 and 51.36±2.33) was both obviously decreased compared with control 8 hour group (70.81±5.01, both P<0.01). Compared with model 8 hour group, the SP-A of HT 8 hour group was obviously increased (P<0.01). Results of light microscopic examination, it was revealed that the alveolar structure of control 1 hour group and control 8 hour group was almost normal. Inflammatory response in lung tissues in model 8 hour group was found to be most serious; compared with model 8 hour group, inflammatory response in lung tissues in model 1 hour group and HT 8 hour group was reduced in certain degree. CONCLUSION: A certain extent of HT may reduce lung injury of early endotoxin induced ALI rats by delaying lowering of alveolar SP-A levels.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Hipotermia , Proteína A Associada a Surfactante Pulmonar/metabolismo , Animais , Líquido da Lavagem Broncoalveolar , Lipopolissacarídeos , Masculino , Ratos , Ratos Wistar
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