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1.
Cell ; 152(1-2): 82-96, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-23313552

RESUMO

The induction of pluripotency or trans-differentiation of one cell type to another can be accomplished with cell-lineage-specific transcription factors. Here, we report that repression of a single RNA binding polypyrimidine-tract-binding (PTB) protein, which occurs during normal brain development via the action of miR-124, is sufficient to induce trans-differentiation of fibroblasts into functional neurons. Besides its traditional role in regulated splicing, we show that PTB has a previously undocumented function in the regulation of microRNA functions, suppressing or enhancing microRNA targeting by competitive binding on target mRNA or altering local RNA secondary structure. A key event during neuronal induction is the relief of PTB-mediated blockage of microRNA action on multiple components of the REST complex, thereby derepressing a large array of neuronal genes, including miR-124 and multiple neuronal-specific transcription factors, in nonneuronal cells. This converts a negative feedback loop to a positive one to elicit cellular reprogramming to the neuronal lineage.


Assuntos
Diferenciação Celular , Fibroblastos/citologia , MicroRNAs/genética , Neurônios/citologia , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Animais , Linhagem Celular , Linhagem da Célula , Regulação para Baixo , Humanos , Camundongos , MicroRNAs/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Splicing de RNA , Sinapses
2.
Mol Cell ; 76(4): 590-599.e4, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31522989

RESUMO

Full-length transcription in the majority of human genes depends on U1 snRNP (U1) to co-transcriptionally suppress transcription-terminating premature 3' end cleavage and polyadenylation (PCPA) from cryptic polyadenylation signals (PASs) in introns. However, the mechanism of this U1 activity, termed telescripting, is unknown. Here, we captured a complex, comprising U1 and CPA factors (U1-CPAFs), that binds intronic PASs and suppresses PCPA. U1-CPAFs are distinct from U1-spliceosomal complexes; they include CPA's three main subunits, CFIm, CPSF, and CstF; lack essential splicing factors; and associate with transcription elongation and mRNA export complexes. Telescripting requires U1:pre-mRNA base-pairing, which can be disrupted by U1 antisense oligonucleotide (U1 AMO), triggering PCPA. U1 AMO remodels U1-CPAFs, revealing changes, including recruitment of CPA-stimulating factors, that explain U1-CPAFs' switch from repressive to activated states. Our findings outline this U1 telescripting mechanism and demonstrate U1's unique role as central regulator of pre-mRNA processing and transcription.


Assuntos
Núcleo Celular/metabolismo , Fator de Especificidade de Clivagem e Poliadenilação/metabolismo , Clivagem do RNA , Precursores de RNA/biossíntese , RNA Mensageiro/biossíntese , Ribonucleoproteína Nuclear Pequena U1/metabolismo , Transcrição Gênica , Regiões 3' não Traduzidas , Transporte Ativo do Núcleo Celular , Sítios de Ligação , Núcleo Celular/genética , Fator de Especificidade de Clivagem e Poliadenilação/genética , Fator Estimulador de Clivagem/genética , Fator Estimulador de Clivagem/metabolismo , Células HeLa , Humanos , Complexos Multiproteicos , Poli A/metabolismo , Ligação Proteica , Precursores de RNA/genética , RNA Mensageiro/genética , Ribonucleoproteína Nuclear Pequena U1/genética
3.
Analyst ; 149(3): 925-934, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38192226

RESUMO

Here we report the first example of employing hydroxyl-functionalized pillar[5]arene (P5A-C10-OH) as stationary phase for capillary gas chromatographic (GC) separations. The statically coated P5A-C10-OH capillary column possessed moderate polarity and column efficiency of 3233 plates per m determined by n-dodecane. As a result, the P5A-C10-OH column exhibited high-resolution capability for the mixture of 17 analytes from apolar to polar nature. Importantly, it exhibited advantageous performance for high resolution of the challenging isomers of bromonitrobenzene, chloroaniline, bromoaniline, iodoaniline and dimethylaniline with good peak shapes over the P5A-C10 and commercial HP-35 columns. In addition, eight cis-/trans-isomers with diverse types were baseline separated on the P5A-C10-OH column. And the application of detecting isomeric impurities in real samples gave strong evidence of its potential and feasibility for the viable GC analysis.

4.
Anal Bioanal Chem ; 416(6): 1321-1335, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38231255

RESUMO

This work presents the first example of the utilization of polar ester group functionalized pillar[6]arene (P6A-C10-OAc) as a stationary phase for capillary gas chromatographic (GC) separations. The statically coated P6A-C10-OAc column showed a high column efficiency of 5393 plates/m and moderate polar nature. Its resolving capability and retention behaviors were investigated for a mixture of 20 analytes and more than a dozen isomers from apolar to polar in nature. As evidenced, the P6A-C10-OAc column achieved high-resolution separations of all the analytes and good inertness. Importantly, it exhibited distinctly advantageous performance for high resolution of the challenging isomers of xylenes, diethylbenzenes, ethyltoluenes, and halobenzenes over the commercial HP-5 (5% phenyl dimethyl polysiloxane), HP-35 (25% phenyl dimethyl polysiloxane), and PEG-20M (polyethylene glycol) columns.

5.
Dig Dis Sci ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769225

RESUMO

Claudin18.2 is a tight junction protein, highly selective, generally expressed only in normal gastric mucosal epithelial cells, which can effectively maintain the polarity of epithelial and endothelial cells, thus effectively regulating the permeability and conductance of the paracellular pathway. Abnormal expression of Claudin18.2 can occur in various primary malignant tumors, especially gastrointestinal tumors, and even in metastatic foci. It regulates its expression by activating the aPKC/MAPK/AP-1 pathway, and therefore, the Claudin18.2 protein is a pan-cancer target expressed in primary and metastatic lesions in human cancer types. Zolbetuximab (IMAB362), an antibody specific for Claudin18.2, has been successfully tested in a phase III clinical trial, and the results of the study showed that combining Zolbetuximab with chemotherapy notably extends patients' survival and is expected to be a potential first-line treatment for patients with Claudin18.2(+)/HER-2(-) gastric cancer. Here, we systematically describe the biological properties and oncogenic effects of Claudin18.2, centering on its clinical-pathological aspects and the progress of drug studies in gastric cancer, which can help to further explore its clinical value.

6.
J Obstet Gynaecol Res ; 50(3): 334-341, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38105316

RESUMO

INTRODUCTION: Hypertensive disorders of pregnancy (HDP) are one of the main causes of perinatal morbidity. Gut microbiota influences host inflammatory pathways, glucose, and lipid metabolism. However, there is a lack of studies available on gut microbiota in HDP. OBJECTIVES: We investigate the mechanistic and pathogenic role of microbiota in the development of HDP, and want to treat HDP with gut microbiota. METHODS: We performed a case-control study to compare fecal samples of HDP and normotensive pregnant women by 16S ribosomal RNA sequencing. Fecal samples, collected from pregnant women, were divided into groups P and C (pregnant women with HDP and normotension, respectively). There were six pregnant women in group P and nine pregnant women in group C. Age of pregnant women is from 18 to 40 years and gestational age is from 27 to 40 weeks. DNA was extracted from fecal samples; a gene library was constructed and analyzed using bioinformatics. Finally, we determined the changes in the microbiome by alpha diversity, beta diversity, classification abundance, and taxonomic composition analyses. RESULTS: Escherichia (10.48% in group P and 0.61% in group C) was the dominant bacterium in HDP patients by classification abundance analysis, which can lead to the development of preeclampsia through inflammatory response. We found that pregnant women with HDP had higher abundance of Rothia (p = 0.04984), Actinomyces (p = 0.02040), and Enterococcus (p = 0.04974) and lower abundance of Coprococcus (p = 0.04955) than pregnant women with normotension for the first time by taxonomic composition analysis. Based on the Kyoto Encyclopedia of Genes and Genomes database analysis, physiological and biochemical functions of HDP patients were significantly weakened, especially in energy metabolism. CONCLUSIONS: We found the effect of changes in gut microbiota on the development of HDP. In comparison with group C, group P contained more harmful bacteria and less beneficial bacteria, which are associated with HDP. Our research further provides a basis for a clinical application for HDP treatment using antibiotics and probiotic supplementation.


Assuntos
Microbioma Gastrointestinal , Hipertensão Induzida pela Gravidez , Pré-Eclâmpsia , Gravidez , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Lactente , Projetos Piloto , Microbioma Gastrointestinal/genética , Estudos de Casos e Controles , Pressão Sanguínea
7.
Chem Biodivers ; 21(3): e202301795, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38268034

RESUMO

This work reports the first example of employing ester-functionalized pillar[5]arene (P5A-C10-OAc) stationary phase for gas chromatography (GC) separations. The as-fabricated P5A-C10-OAc column achieved improved column efficiency of 4270 plates/m and separation performance in contrast to the P5-C10-Br column. The P5A-C10-OAc column showed good separation performance for a wide range of analytes such as alkanes, bromoalkanes, ketones, fatty acid methyl esters, aldehydes, alcohols, halobenzenes, anilines, phenols, naphthalenes, and showed sharp and symmetrical peak shapes for analytes that are liable to peak-tailing in GC analysis. As testified by the challenging isomer mixtures (bromonitrobenzene, chloronitrobenzene, bromobenzaldehyde, chlorobenzaldehyde, nitrobenzaldehyde), the P5A-C10-OAc column exhibited comprehensively higher separation capability than the P5A-C10-Br, P5A-C10 and commercial HP-35 columns. This work demonstrates the great potential of pillararene-based stationary phases as a new type of stationary phases for GC separations.


Assuntos
Álcoois , Compostos de Anilina , Reprodutibilidade dos Testes , Cromatografia Gasosa/métodos , Compostos de Anilina/química , Isomerismo
8.
Future Oncol ; 19(25): 1729-1739, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37650748

RESUMO

Objective: To investigate the safety and efficacy of anlotinib hydrochloride capsules in stage III-IV non-small-cell lung cancer (NSCLC). Methods: NSCLC patients received anlotinib monotherapy or combination therapy. The primary end point was adverse reactions during anlotinib treatment and the secondary end point was progression-free survival. Results: During anlotinib treatement, 41.85% (167/399) of patients experienced adverse reactions, and the monotherapy group had a lower incidence than the combination group (36.89 vs 49.68%; p = 0.012). The median progression-free survival of patients in the monotherapy group was significantly lower than that in the combination group (5 vs 6 months; p = 0.0119). Conclusion: Compared with anlotinib monotherapy, combination therapy resulted in longer PFS and a higher incidence of adverse reactions in patients with NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Cápsulas , Inibidores da Angiogênese , Inibidores de Proteínas Quinases
9.
Surg Endosc ; 37(1): 518-527, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36002683

RESUMO

BACKGROUND: It is important to identify gallbladder polyps (GPs) with malignant potential and avoid unnecessary cholecystectomy by constructing prediction model. The aim of the study is to develop a Bayesian network (BN) prediction model for GPs with malignant potential in a long diameter of 8-15 mm based on preoperative ultrasound. METHODS: The independent risk factors for GPs with malignant potential were screened by χ2 test and Logistic regression model. Prediction model was established and validated using data from 1296 patients with GPs who underwent cholecystectomy from January 2015 to December 2019 at 11 tertiary hospitals in China. A BN model was established based on the independent risk variables. RESULTS: Independent risk factors for GPs with malignant potential included age, number of polyps, polyp size (long diameter), polyp size (short diameter), and fundus. The BN prediction model identified relationships between polyp size (long diameter) and three other variables [polyp size (short diameter), fundus and number of polyps]. Each variable was assigned scores under different status and the probabilities of GPs with malignant potential were classified as [0-0.2), [0.2-0.5), [0.5-0.8) and [0.8-1] according to the total points of [- 337, - 234], [- 197, - 145], [- 123, - 108], and [- 62,500], respectively. The AUC was 77.38% and 75.13%, and the model accuracy was 75.58% and 80.47% for the BN model in the training set and testing set, respectively. CONCLUSION: A BN prediction model was accurate and practical for predicting GPs with malignant potential patients in a long diameter of 8-15 mm undergoing cholecystectomy based on preoperative ultrasound.


Assuntos
Doenças da Vesícula Biliar , Neoplasias da Vesícula Biliar , Pólipos , Humanos , Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Neoplasias da Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/patologia , Teorema de Bayes , Doenças da Vesícula Biliar/cirurgia , Colecistectomia , Ultrassonografia , Pólipos/diagnóstico por imagem , Pólipos/cirurgia , Pólipos/patologia , Estudos Retrospectivos
10.
Surg Endosc ; 37(7): 5453-5463, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37041283

RESUMO

BACKGROUND: Polyp size of 10 mm is insufficient to discriminate neoplastic and non-neoplastic risk in patients with gallbladder polyps (GPs). The aim of the study is to develop a Bayesian network (BN) prediction model to identify neoplastic polyps and create more precise criteria for surgical indications in patients with GPs lager than 10 mm based on preoperative ultrasound features. METHODS: A BN prediction model was established and validated based on the independent risk variables using data from 759 patients with GPs who underwent cholecystectomy from January 2015 to August 2022 at 11 tertiary hospitals in China. The area under receiver operating characteristic curves (AUCs) were used to evaluate the predictive ability of the BN model and current guidelines, and Delong test was used to compare the AUCs. RESULTS: The mean values of polyp cross-sectional area (CSA), long, and short diameter of neoplastic polyps were higher than those of non-neoplastic polyps (P < 0.0001). Independent neoplastic risk factors for GPs included single polyp, polyp CSA ≥ 85 mm 2, fundus with broad base, and medium echogenicity. The accuracy of the BN model established based on the above independent variables was 81.88% and 82.35% in the training and testing sets, respectively. Delong test also showed that the AUCs of the BN model was better than that of JSHBPS, ESGAR, US-reported, and CCBS in training and testing sets, respectively (P < 0.05). CONCLUSION: A Bayesian network model was accurate and practical for predicting neoplastic risk in patients with gallbladder polyps larger than 10 mm based on preoperative ultrasound features.


Assuntos
Doenças da Vesícula Biliar , Neoplasias da Vesícula Biliar , Pólipos , Humanos , Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Neoplasias da Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/patologia , Teorema de Bayes , Doenças da Vesícula Biliar/cirurgia , Ultrassonografia , Pólipos/diagnóstico por imagem , Pólipos/cirurgia , Pólipos/patologia , Estudos Retrospectivos
11.
World J Surg ; 47(3): 773-784, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36607391

RESUMO

BACKGROUND: Microvascular invasion (MVI) has been reported to be an independent prognostic factor of recurrence and poor overall survival in patients with intrahepatic cholangiocarcinoma (ICC). This study aimed to explore the preoperative independent risk factors of MVI and establish a Bayesian network (BN) prediction model to provide a reference for surgical diagnosis and treatment. METHODS: A total of 531 patients with ICC who underwent radical resection between 2010 and 2018 were used to establish and validate a BN model for MVI. The BN model was established based on the preoperative independent variables. The ROC curves and confusion matrix were used to assess the performance of the model. RESULTS: MVI was an independent risk factor for relapse-free survival (RFS) (P < 0.05). MVI has a correlation with postoperative recurrence, early recurrence (< 6 months), median RFS and median overall survival (all P < 0.05). The preoperative independent risk variables of MVI included obstructive jaundice, prognostic nutritional index, CA19-9, tumor size, and major vascular invasion, which were used to establish the BN model. The AUC of the BN model was 78.92% and 83.01%, and the accuracy was 70.85% and 77.06% in the training set and testing set, respectively. CONCLUSION: The BN model established based on five independent risk variables for MVI is an effective and practical model for predicting MVI in patients with ICC.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Teorema de Bayes , Invasividade Neoplásica , Estudos Retrospectivos , Recidiva Local de Neoplasia/patologia , Colangiocarcinoma/cirurgia , Colangiocarcinoma/patologia , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/cirurgia
12.
Chaos Solitons Fractals ; 169: 113294, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36891356

RESUMO

Predicting the evolutionary dynamics of the COVID-19 pandemic is a complex challenge. The complexity increases when the vaccination process dynamic is also considered. In addition, when applying a voluntary vaccination policy, the simultaneous behavioral evolution of individuals who decide whether and when to vaccinate must be included. In this paper, a coupled disease-vaccination behavior dynamic model is introduced to study the coevolution of individual vaccination strategies and infection spreading. We study disease transmission by a mean-field compartment model and introduce a non-linear infection rate that takes into account the simultaneity of interactions. Besides, the evolutionary game theory is used to investigate the contemporary evolution of vaccination strategies. Our findings suggest that sharing information with the entire population about the negative and positive consequences of infection and vaccination is beneficial as it boosts behaviors that can reduce the final epidemic size. Finally, we validate our transmission mechanism on real data from the COVID-19 pandemic in France.

13.
Chem Biodivers ; 20(8): e202300350, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37377049

RESUMO

This work firstly reported a new polycaprolactone based material functionalized with guanidinium ionic liquid (PCL-GIL) as the stationary phase with high resolution performance for capillary gas chromatography (GC). It is composed of polycaprolactone (PCL) and guanidinium ionic liquid (GIL) with amphiphilic conformation. The PCL-GIL capillary column coated by static method exhibited high column efficiency of 3942 plates/m and moderate polarity. As a result, the PCL-GIL column exhibited high-resolution capability. For a mixture of 27 analytes with a wide ranging polarity and outperformed the PCL-2OH and HP-35 columns, showing its advantageous separation capability for analytes of diverse types. Moreover, the PCL-GIL column showed high resolving capability for various positional isomers and cis-/trans-isomers, including alkylbenzenes, chlorobenzenes, naphthalenes, bromonitrobenzenes, chloronitrobenzenes, benzaldehydes, phenols, alcohols, respectively. In a word, PCL derivatized by GIL units as a new type of stationary phase has a promising future in GC separations.


Assuntos
Líquidos Iônicos , Guanidina , Reprodutibilidade dos Testes , Cromatografia Gasosa/métodos
14.
Mikrochim Acta ; 190(9): 357, 2023 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-37597027

RESUMO

Novel chiral capillary electrochromatography (CEC) microsystems were constructed based on Aspergillus sp. CM96. As a newly discovered intrinsic characteristic of the cell, cell chirality occupies an essential position in life evolution. Aspergillus sp. CM96 spore (CM96s) was chosen as a proof of concept to develop chiral capillary columns. Interestingly, various types of amino acid (AA) enantiomers were baseline separated under the optimized conditions. Furthermore, the time-dependent chiral interactions between AAs and CM96s were explored in a wider space. Pectinases generated from Aspergillus sp. CM96 fermentation were immobilized onto graphene oxide-functionalized capillary silica monoliths for separating AA enantiomers. Molecular docking simulations were performed to explore chiral separation mechanisms of pectinase for AA enantiomers. These results indicated that Aspergillus sp. CM96-based CEC microsystems have a significant advantage for chiral separation.


Assuntos
Eletrocromatografia Capilar , Simulação de Acoplamento Molecular , Aspergillus , Aminoácidos , Dióxido de Silício
15.
Cardiovasc Drugs Ther ; 36(3): 505-509, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33779938

RESUMO

BACKGROUND: Heart failure (HF) is one of the most serious health concerns worldwide. Anemia is a highly prevalent comorbidity and outcome predictor in HF patients. Sodium glucose co-transport 2 (SGLT2) inhibitors have been demonstrated to reduce the risk of cardiovascular death and HF hospitalization in HF patients. PURPOSE: This investigator-initiated, interventional, prospective, double-blind, multicenter study is designed to investigate whether anemia correction is one of the prerequisites and determinants related to the beneficial effects of dapagliflozin in HF patients. METHODS AND RESULTS: Up to 2030 HF participants receiving standard care will be randomly assigned to either oral dapagliflozin 10 mg once daily or placebo 10 mg once daily for 12 months. The primary outcome is the composite incidence of hospital admission for HF and all-cause death. Secondary outcomes include change in the Kansas City Cardiomyopathy Questionnaire (KCCQ) score and change in 6-min walk distance and hemoglobin level. Patients will be followed for 12 months after randomization. CONCLUSIONS: The ADIDAS trial offers an opportunity to assess the hemoglobin change and association between hemoglobin change and readmissions due to heart failure and all-cause death in patients with heart failure treated with dapagliflozin or placebo. This study could highlight if dynamic hemoglobin change is related to the outcome for HF patients. TRIAL REGISTRATION: ClinicalTrials.gov ; NCT04707261. Registration date, 2020/12/01, "retrospectively registered".


Assuntos
Anemia , Insuficiência Cardíaca , Anemia/diagnóstico , Anemia/tratamento farmacológico , Compostos Benzidrílicos , Glucosídeos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Estudos Prospectivos , Volume Sistólico
16.
Chem Biodivers ; 19(12): e202200829, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36372775

RESUMO

In this work, a novel capillary column (C4A-mPEG) with a calixarene-based polymer stationary phase (poly(ethylene glycol) methyl ether-functionalized 4-tert-butylcalix[4]arene) was designed and used for gas chromatographic (GC) separations. The C4A-mPEG capillary column, prepared by the static coating method, showed moderate polarity and a column efficiency of 2332 plates/m, determined by 1-octanol at 120 °C. The separation features of C4A-mPEG stationary phase, resulting from its unique structure and multiple molecular recognition processes with analytes, including π-π, H-bonding, dipole-dipole, and van der Waals interactions, allowed to obtain high-resolution performances for a wide range of compounds and their isomers, especially benzaldehydes, phenols, and anilines. Moreover, compared with 4-tertbutyl calix[4]arene (C4A) and polyethylene glycol (PEG) stationary phases, a higher resolving capability was also observed for the separation of toluidine and xylidine isomers.


Assuntos
Éteres Metílicos , Polietilenoglicóis , Reprodutibilidade dos Testes , Cromatografia Gasosa/métodos , Polietilenoglicóis/química
17.
Sensors (Basel) ; 22(14)2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35890845

RESUMO

With the development of machine learning, data-driven mechanical fault diagnosis methods have been widely used in the field of PHM. Due to the limitation of the amount of fault data, it is a difficult problem for fault diagnosis to solve the problem of unbalanced data sets. Under unbalanced data sets, faults with little historical data are always difficult to diagnose and lead to economic losses. In order to improve the prediction accuracy under unbalanced data sets, this paper proposes MeanRadius-SMOTE based on the traditional SMOTE oversampling algorithm, which effectively avoids the generation of useless samples and noise samples. This paper validates the effectiveness of the algorithm on three linear unbalanced data sets and four step unbalanced data sets. Experimental results show that MeanRadius-SMOTE outperforms SMOTE and LR-SMOTE in various evaluation indicators, as well as has better robustness against different imbalance rates. In addition, MeanRadius-SMOTE can take into account the prediction accuracy of the overall and minority class, which is of great significance for engineering applications.

18.
Entropy (Basel) ; 24(1)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35052159

RESUMO

We propose a reinforcement learning (RL) approach to compute the expression of quasi-stationary distribution. Based on the fixed-point formulation of quasi-stationary distribution, we minimize the KL-divergence of two Markovian path distributions induced by candidate distribution and true target distribution. To solve this challenging minimization problem by gradient descent, we apply a reinforcement learning technique by introducing the reward and value functions. We derive the corresponding policy gradient theorem and design an actor-critic algorithm to learn the optimal solution and the value function. The numerical examples of finite state Markov chain are tested to demonstrate the new method.

19.
Analyst ; 146(1): 48-63, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33211035

RESUMO

DNA possesses various chemical and physical properties which make it important in biological analysis. The opportunity for DNA to 'meet' capillary-based microsystems is rapidly increasing owing to the expanding development of miniaturization. Novel capillary-based methods can provide favourable platforms for DNA-ligand interaction assay, DNA translocation study, DNA separation, DNA aptamer selection, DNA amplification assay, and DNA digestion. Meanwhile, DNA exhibits great potential in the fabrication of new capillary-based biosensors and enzymatic bioreactors. Moreover, DNA has received significant research interest in improving capillary electrophoresis (CE) performance. We focus on highlighting the advantages of combining DNA and capillary-based microsystems. The general trend presented in this review suggests that the 'meeting' has offered a stepping stone for the application of DNA and capillary-based microsystems in the field of analytical chemistry.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA/genética , Eletroforese Capilar , Miniaturização
20.
Appl Math Comput ; 403: 126172, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33758440

RESUMO

Nowadays, vaccination is the most effective way to control the epidemic spreading. In this paper, an epidemic SEIRV (susceptible-exposed-infected-removed -vaccinated) model and an evolutionary game model are established to analyze the difference between mandatory vaccination method and voluntary vaccination method on heterogeneous networks. Firstly, we divide the population into four categories, including susceptible individuals, exposed individuals, infected individuals and removed individuals. Based on the mean field approximation theory, differential equations are developed to characterize the changes of the proportions of the four groups over time under mandatory vaccination. Then through the analysis of the differential equations, the disease-free equilibrium point (DFE) and the endemic disease equilibrium point (EDE) are obtained. Also, the basic reproduction number is obtained by the next-generation matrix method and the stability analysis of the equilibrium points is performed. Next, by considering factors such as vaccination cost, treatment cost and government subsidy rate, differential equations are established to represent the change of vaccination rate over time. By analyzing the final vaccination coverage rate, we can get the minimum vaccination cost to make infectious disease disappear. Finally, the Monte Carlo method is used for numerical simulation to verify the results obtained from the theoretical analysis. Using the SARS-Cov-2 pandemic data from Wuhan, China, the experimental results show that when the effectiveness rate of vaccination is 0.75, the vaccination cost is not higher than 0.886 so that the vaccination strategy can be spread among the population. If mandatory vaccination is adopted, the minimum vaccination rate is 0.146.

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