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2.
Entropy (Basel) ; 23(2)2021 Feb 08.
Article in English | MEDLINE | ID: mdl-33567638

ABSTRACT

Entropy measures the uncertainty associated with a random variable. It has important applications in cybernetics, probability theory, astrophysics, life sciences and other fields. Recently, many authors focused on the estimation of entropy with different life distributions. However, the estimation of entropy for the generalized Bilal (GB) distribution has not yet been involved. In this paper, we consider the estimation of the entropy and the parameters with GB distribution based on adaptive Type-II progressive hybrid censored data. Maximum likelihood estimation of the entropy and the parameters are obtained using the Newton-Raphson iteration method. Bayesian estimations under different loss functions are provided with the help of Lindley's approximation. The approximate confidence interval and the Bayesian credible interval of the parameters and entropy are obtained by using the delta and Markov chain Monte Carlo (MCMC) methods, respectively. Monte Carlo simulation studies are carried out to observe the performances of the different point and interval estimations. Finally, a real data set has been analyzed for illustrative purposes.

3.
IEEE Trans Neural Netw Learn Syst ; 32(5): 2015-2029, 2021 05.
Article in English | MEDLINE | ID: mdl-32497012

ABSTRACT

In applications of domain adaptation, there may exist multiple source domains, which can provide more or less complementary knowledge for pattern classification in the target domain. In order to improve the classification accuracy, a decision-level combination method is proposed for the multisource domain adaptation based on evidential reasoning. The classification results obtained from different source domains usually have different reliabilities/weights, which are calculated according to domain consistency. Therefore, the multiple classification results are discounted by the corresponding weights under belief functions framework, and then, Dempster's rule is employed to combine these discounted results. In order to reduce errors, a neighborhood-based cautious decision-making rule is developed to make the class decision depending on the combination result. The object is assigned to a singleton class if its neighborhoods can be (almost) correctly classified. Otherwise, it is cautiously committed to the disjunction of several possible classes. By doing this, we can well characterize the partial imprecision of classification and reduce the error risk as well. A unified utility value is defined here to reflect the benefit of such classification. This cautious decision-making rule can achieve the maximum unified utility value because partial imprecision is considered better than an error. Several real data sets are used to test the performance of the proposed method, and the experimental results show that our new method can efficiently improve the classification accuracy with respect to other related combination methods.

4.
Entropy (Basel) ; 22(10)2020 Sep 30.
Article in English | MEDLINE | ID: mdl-33286875

ABSTRACT

In this paper, the evidential estimation method for the parameters of the mixed exponential distribution is considered when a sample is obtained from Type-II progressively censored data. Different from the traditional statistical inference methods for censored data from mixture models, here we consider a very general form where there is some uncertain information about the sub-class labels of units. The partially specified label information, as well as the censored data are represented in a united frame by mass functions within the theory of belief functions. Following that, the evidential likelihood function is derived based on the completely observed failures and the uncertain information included in the data. Then, the optimization method using the evidential expectation maximization algorithm (E2M) is introduced. A general form of the maximal likelihood estimates (MLEs) in the sense of the evidential likelihood, named maximal evidential likelihood estimates (MELEs), can be obtained. Finally, some Monte Carlo simulations are conducted. The results show that the proposed estimation method can incorporate more information than traditional EM algorithms, and this confirms the interest in using uncertain labels for the censored data from finite mixture models.

5.
Chaos ; 30(1): 013133, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32013470

ABSTRACT

The probability density function of stochastic differential equations is governed by the Fokker-Planck (FP) equation. A novel machine learning method is developed to solve the general FP equations based on deep neural networks. The proposed algorithm does not require any interpolation and coordinate transformation, which is different from the traditional numerical methods. The main novelty of this paper is that penalty factors are introduced to overcome the local optimization for the deep learning approach, and the corresponding setting rules are given. Meanwhile, we consider a normalization condition as a supervision condition to effectively avoid that the trial solution is zero. Several numerical examples are presented to illustrate performances of the proposed algorithm, including one-, two-, and three-dimensional systems. All the results suggest that the deep learning is quite feasible and effective to calculate the FP equation. Furthermore, influences of the number of hidden layers, the penalty factors, and the optimization algorithm are discussed in detail. These results indicate that the performances of the machine learning technique can be improved through constructing the neural networks appropriately.

6.
Chinese Journal of Virology ; (6): 392-397, 2013.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-339939

ABSTRACT

This research aims to evaluate the application of Real - time cell assay (RTCA) based on microelectronics sensor technology in the detection of HEV71 induced cell lesion. Growth indexes of RD cells at different stages were observed dynamically, appropriate cell concentration was selected to test HEV71 infectivity and to determine the HEV71 neutralizing antibody titer in serum. The traditional microplate test was used as methodology comparison and results validation at the same time. Cell impedance was transformed to cell index (CI) value and visual dynamic curve through software, and the result showed that the observation of HEV71 infectivity was more than 5d when the RD cells concentration was 1. 5 X 10(4) hole on the 96 electronic orifice plate. Compared with the traditional cytopathic effect (CPE) through microscope observation method, the end point judgment results were consistent between these two methods at 132h (about 5. 5d) post virus inoculation. In the neutralization tests, three CI values of neutralizing antibody titers against HEV71 in human serum were correspond to those obtained from traditional 96 microplate microscopy. RTCA also suggested that the presentation time of CPE induced by the i virus could be different even the end point judgment was the same with the same neutralization antibody titer. Compared with the traditional microplate monitoring method, RTCA can save labor and eliminate the hands-on error in the monitoring HEV71 infectivity and antibody titer detection in serum. RTCA can be served as one of the supplementary methods of traditional detection method, with the advantages of dynamically observing the occurrence and development of cell pathological changes, and the variation of virus infectivity and serum neutralizing antibodies.


Subject(s)
Humans , Antibodies, Neutralizing , Blood , Antibodies, Viral , Blood , Cell Line, Tumor , Cytopathogenic Effect, Viral , Electric Impedance , Enterovirus A, Human , Allergy and Immunology , Virulence , Enterovirus Infections , Virology , Microelectrodes , Neutralization Tests , Methods
7.
Leuk Lymphoma ; 53(12): 2423-9, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22616558

ABSTRACT

Recurrent mutations of isocitrate dehydrogenase isoforms 1 and 2 (IDH1 and IDH2) have recently been studied in adult patients with acute myeloid leukemia (AML). A meta-analysis was performed to demonstrate their controversial prognostic impacts. The associations of IDH1 or IDH2 mutations with other molecular abnormalities were also investigated. In patients with AML, IDH1/2 mutations were significantly associated with normal karyotype and isolated trisomy 8 (p < .05). After adjusting for well-studied prognostic factors, IDH1 mutation seems to be associated with subtle but significantly inferior event-free survival (EFS) (p = 0.02) and possible adverse overall survival (OS) (p = 0.13) in patients with AML, especially in the favorable genotype subset with mutated NPM1 but without FLT3-ITD mutation (p < 0.05). Longer OS (p = 0.01) and better EFS tendency (p = 0.18) are implicated in patients with IDH2 mutations, which suggests that IDH2 mutations appear to confer a favorable prognosis. Moreover, IDH1 and IDH2 mutations may play a more important role in abnormal cytogenetics subgroups such as isolated trisomy 8. Screening of IDH1/2 mutations could help to identify patients at high risk within some subsets of AML.


Subject(s)
Biomarkers, Tumor/genetics , Isocitrate Dehydrogenase/genetics , Leukemia, Myeloid, Acute/genetics , Mutation , Disease-Free Survival , Female , Humans , Leukemia, Myeloid, Acute/enzymology , Leukemia, Myeloid, Acute/pathology , Male , Nuclear Proteins/genetics , Nucleophosmin , Prognosis , Regression Analysis
8.
Chinese Journal of Virology ; (6): 437-442, 2010.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-286097

ABSTRACT

To analyze the epidemiological and etiological characteristics of Hand-Foot-and-Mouth disease (HFMD) in Shanghai in 2009, epidemiological data was retrieved from the National Notifiable Disease Report System (NNDRS). Nucleic acid of enterovirus (EV) was detected by real-time RT-PCR from 799 HFMD cases from 15 districts/counties in Shanghai; the complete sequences of VP1 encoding region of several identified EV71 strains and sequences of VP4 encoding region of several untyped EV were determined and analyzed. Analysis and summary of the epidemiological data was conducted with Microsoft Excel, and sequence analyses were conducted with both BioEdit and MEGA software. Untyped EV was identified through comparing the VP4 sequence to sequence database using BLAST online service. It was showed that all the 18 districts/counties had reported HFMD cases; children less than 6 years old were the most susceptible population group; the peak of epidemics of HFMD was from April to July; EV71 and Coxsackievirus A16 (CA16) were the major pathogens for this epidemic, but the constituent ratio of EV71 and CA16 was different in different months and regions; CA16 infection was mainly responsible for the mild HFMD, but EV71 for most of the severe cases; EV71 strains of Shanghai were clustered with representatives of subgenotype C4a and showed the highest identity to them, based on the sequence analyses of VP1 encoding region; 2 of the untyped EV were identified as CA2 and CA10 respectively. All the results indicated that EV71 and CA16 were the major pathogens for the epidemic of HFMD in Shanghai, 2009; the circulating EV71 belonged to subgenotype C4a. Besides, other types of EV (for example: CA2 and CA10) were also responsible for a few of the HFMD cases.


Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Infant , Male , China , Epidemiology , Enterovirus A, Human , Classification , Genetics , Epidemics , Hand, Foot and Mouth Disease , Epidemiology , Virology , Molecular Sequence Data , Phylogeny
9.
Chinese Journal of Virology ; (6): 178-184, 2008.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-334827

ABSTRACT

A simple and sensitive Reverse Transcription Loop-mediated Isothermal Amplification (RT-LAMP) method was established to provide a new alternative for clinical diagnosis of Avian influenza A H5N1 virus. The method employed a set of six specially designed primers that recognized eight distinct sequences of the target for amplification of nucleic acid under isothermal conditions. In current study, fifty-one experimentally infected animal specimens and viral cultures that had been tested were analyzed by RT-LAMP for NA gene and HA gene, respectively. The amplification process of LAMP was monitored in real-time by the addition of SYBR Green dye. Meanwhile, the result showed high correlation between nested PCR and RT-LAMP. The specificity of the RT-LAMP assay was confirmed by restriction enzyme digestion analysis and sequencing of the amplified product. When the sensitivity of this assay was tested by serial 10-fold dilutions of RNA molecules from specimens, it was found that the RT-LAMP method achieved theoretically a sensitivity of 10 RNA molecules. Thus, we concluded that the RT-LAMP assay has potential usefulness for rapid detection of the Avian influenza A H5N1 virus.


Subject(s)
Animals , Birds , Influenza A Virus, H5N1 Subtype , Genetics , Influenza in Birds , Diagnosis , Virology , Nucleic Acid Amplification Techniques , Methods , Reproducibility of Results , Reverse Transcriptase Polymerase Chain Reaction , Methods , Sensitivity and Specificity
10.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-254131

ABSTRACT

<p><b>OBJECTIVE</b>To understand the genotypes of human metapneumovirus (hMPV) and the genetic character of hMPV attachment protein G sequence in Hunan, China.</p><p><b>METHODS</b>232 nasopharyngeal aspirates (NPA) samples from hospitalized children with acute respiratory infections were collected from Hunan, China in 2005. HMPV was detected. The full length of G glycoprotein genes were amplified and sequenced. Bioinformatics soft-wares were employed to analyze the sequences.</p><p><b>RESULTS</b>17/232 (7.3%) were showed hMPV positive. And co-infection rate with other viruses is 35%. The diagnoses of these hMPV positive cases are pneumonia, bronchiolitis and bronchopneumonia. Phylogenetic analysis for G genes from 13 hMPVs revealed the existence of four major subgroups: A1, A2, B1, B2 in Hunan, China in 2005. There are four types of sequence lengths of hMPV G glycoprotein, which are 711, 675, 660, 696nt. It is different in potential N-linked glycosylation sites and number of cysteine residues among these hMPVs of Hunan, China and Beijing, China. Also it is different from those in Japan and North America.</p><p><b>CONCLUSION</b>The investigation of hMPV from Hunan, China in 2005 revealed the high speed of genetic variation and the marked character of geographic epidemic differences.</p>


Subject(s)
Child , Humans , Amino Acid Sequence , China , Epidemiology , Genotype , Glycoproteins , Classification , Genetics , Metapneumovirus , Classification , Genetics , Molecular Sequence Data , Phylogeny , RNA, Viral , Genetics , Respiratory Syncytial Virus Infections , Epidemiology , Virology , Sequence Homology, Amino Acid , Viral Proteins , Classification , Genetics
11.
Chinese Journal of Virology ; (6): 447-453, 2007.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-334867

ABSTRACT

The full-length genome of one human bocavirus (HBoV) and the VP1 sequences of nine HBoV were amplified from patients' samples by PCR, cloned into pGEM-T vector separately, and sequenced. In this study, the one full length gemome and nine VP1 sequences of HBoV were aligened with 14 sequences of Parvoviruses which were canonical exemplars in Parvovirinae. Phylogenetic analysis showed that HBoV capsid sequences positioned closely to B19 parvovirus, although they positioned far in phylogenetic tree based on full length genome. Many similarities were found between HBoV and B19 in capsid by alignment on secondary structural elements. Because both B19 and HBoV are the only Parvoviruses that infect mankind, so study on HBoV may be used for reference to B19 which had been studied for about 30 years. By analysis of mutational sites, HBoV capsid protein showed a highly conserved secondary structural elements, but highly active in VP1-U, leading end of VP2 and insertions between the strands of the betaG-H. This cued that HBoV inclined to immune evasion and infectant adaptive faculty.


Subject(s)
Humans , Amino Acid Sequence , Base Sequence , Bocavirus , Classification , Genetics , Capsid Proteins , Chemistry , Genetics , Cloning, Molecular , Conserved Sequence , Genome, Viral , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction
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