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1.
IEEE Trans Cybern ; 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32224473

RESUMO

This article studies the problem of the optimal stealth attack strategy design for linear cyber-physical systems (CPSs). Virtual systems that reflect the attacker's target are constructed, and a linear attack model with varying gains is designed based on the virtual models. Unlike the existing optimal stealth attack strategies that are designed based on sufficient conditions, necessary and sufficient conditions are, respectively, established to achieve the optimal attack performance while maintaining stealth in virtue of the solvability of certain coupled recursive Riccati difference equations (RDEs). Under those conditions, an optimal stealth attack strategy is constructed by an offline algorithm. A simulation example is applied to verify the effectiveness of the presented technical scheme.

2.
Chemistry ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32129523

RESUMO

Manipulating the collective molecular movements to implement macroscopic mechanical response of bulk material is attractive and challenging. Here, we synthesize an organic-inorganic hybrid single crystal that exhibits a giant macroscopic shape transformation with a remarkable thermal hysteretic feature. The colossal anisotropic shape change, which manifests as an abrupt elongation of ca. 9% along crystallographic c-axis and a concomitant contraction of ca. 9% in a perpendicular direction, is induced by a significant reorientation of imidazoliums accompanied with a substantial configurational variation in CuBr 4 2- complex anions. The synergistic motions of both the molecular cations and anions engender a remarkable large thermal hysteresis (> 30 K) in the shape transformation of single crystal, implying this material may play a role in alternating memory media. Furthermore, due to the stable crystal lattice, a single crystal that demonstrates naked-eye detectable large shape transformation was used as a thermal actuator to spontaneously control an electric circuit by temperature variation.

3.
Int J Health Plann Manage ; 35(1): 280-289, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31657493

RESUMO

Grandparents caring for grandchildren has become a common experience in China. However, the health implications of grandparenting, especially for health self-management, remain unclear. A cross-sectional study was conducted to investigate the effects of grandparenting on health self-management in older adults in China. Information on socioeconomic characteristics, grandparenting, and health self-management was collected through interviewer-administered questionnaires. Age less than 50, male gender, higher education level, being a local resident, having a chronic illness, and supporting themselves financially were all factors that were significantly positively associated with health self-management (P < .05) in grandparents. Grandparenting characteristics, including caring for grandchildren at night, a caregiving burden of more than 50%, poorly behaved grandchildren, caring for grandchildren more than 6 hours per day, and caring for grandchildren less than 1 year in age were significantly negatively associated with health self-management in grandparents (P < .05). Multiple regression analyses indicated that grandparent age, receiving financial support from children, being a local resident, education level, grandchild behavior and age, and being an urban resident were all statistically significant factors associated with health self-management in grandparents involved in grandparenting. Taken together, these results suggested that financial condition and caregiving burden might be the major factors affecting health self-management in grandparents involved in grandparenting.

4.
IEEE Trans Cybern ; 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31871007

RESUMO

This article studies the problem of H∞ controller design for discrete-time T-S fuzzy systems under an event-triggered (ET) communication mechanism. By proposing a new asynchronous premise reconstruction approach, new types of ET fuzzy controllers are designed to overcome the challenges caused by the mismatch of premise variables, in which the gains of the designed controllers are automatically updated at different triggering instants according to an online algorithm. By constructing discontinuous Lyapunov functions, it is proved that the proposed ET controllers guarantee the stability and H∞ performance of the closed-loop systems. Two examples are provided to verify the validity of the proposed design method.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31704169

RESUMO

OBJECTIVES: To monitor the serological typing of Haemophilus influenzae(Hi) in the lower respiratory tract infection in western Sichuan, China, the changes in beta-lactam resistance of the strains and the mechanism of beta-lactam resistance in these isolates over the past decade. METHODS: 54 strains of Nontypeable Haemophilus influenzae (NTHi) isolated from 2003 to 2004 and 220 strains of NTHi isolated from 2013 to 2014 were selected randomly. Hi strains were characterized by serological typing, and by PCR analysis of the p6, fucK and cap gene. The MIC values for ampicillin (AMP), Amoxicillin-clavulanic (AMC) acid and cefuroxime (CXM) were determined by broth microdilution susceptibility test. The TEM-1, ROB-1 and ftsI genes of the strain were sequenced; We compared the data obtained over a decade. The mechanisms of beta-lactam resistance and the effect of amino acid substitution of the ftsI gene on the MIC values of AMP, AMC and CXM were analyzed, respectively. RESULTS: 1. The MIC values of AMP, AMC and CXM of the NTHi strains isolated during 2013˜2014 were significantly higher than those of the strains collected during 2003˜2004 by rank sum test, p < 0.05. 2. BLA positive strains were 51.46% (141/274); gene sequencing showed that all 141 beta-lactamase positive strains were TEM-1 type. 3. There were 32 amino acid substitutions of the ftsI gene sequence and three of them had two amino acid substitutions in the NTHi isolated from 2013 to 2014. However, NTHi strains isolated from 2003 to 2004 had only the 9 amino acids substitutions (D350 N, M377I, A437S, G490E, A502 V,V511A, R517H and N526 K). 4. The results of rank sum test showed that only a few amino acids had no significant difference in the MIC values between the three beta-lactams. Ordered multiple classification logistic regression analysis showed that different amino acid replacement patterns of the ftsI gene had different effects on the MIC values of AMP, AMC and CXM, respectively. The main factors affecting the MIC value of AMP were in turn R517H (OR = 7.128), L389 F (OR = 6.999), N526 K (OR = 4.660) and D350 N (OR = 0.450); The main factor influencing the MIC value of AMC was an N526 K mutation (OR = 9.349);The main factors affecting the MIC value of CXM were the mutations S357 N (OR = 37.453) and N526 K (OR = 14.816). 5. Compared with the strains isolated from 2003 to 2004, the gBLNAR and gBLPAR strains isolated from 2013 to 2014 increased significantly from 12.96% (7/54), 9.26% (7/54) to 42.0% (84/220), 45.45% (100/220) respectively, p < 0.001. 6. Only 36.22% of the strains in the ftsI gene mutation fit the condition of group I ˜ III, and the group Ⅲ-like strain was 23.98% (47/196). In addition to M377I, S385 T, L389 F and N526 K mutations, all 47 NTHi strains also had amino acid substitution for D350 N and S357I. In other group, 13 NTHi strains had the same ftsI gene mutation pattern and 24 amino acid substitutions. CONCLUSIONS: Our results confirmed that Hi isolated from the lower respiratory tract of Western Sichuan in China from 2013 to 2014 were NTHi strains. Compared with ten years earler, beta-lactamase producing strains and beta-lactam resistant strains increased rapidly. The amino acid substitution of the ftsI gene was more complex and diversified. So far, although some progress has been made in the study of antibiotical resistance mechanism of NTHi strains, how to control the growth of NTHi resistant strains is still a challenge in China.

6.
Nat Commun ; 10(1): 4805, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641182

RESUMO

Materials demonstrating unusual large positive and negative thermal expansion are fascinating for their potential applications as high-precision microscale actuators and thermal expansion compensators for normal solids. However, manipulating molecular motion to execute huge thermal expansion of materials remains a formidable challenge. Here, we report a single-crystal Cu(II) complex exhibiting giant thermal expansion actuated by collective reorientation of imidazoliums. The circular molecular cations, which are rotationally disordered at a high temperature and statically ordered at a low temperature, demonstrate significant reorientation in the molecular planes. Such atypical molecular motion, revealed by variable-temperature single crystal X-ray diffraction and solid-state NMR analyses, drives an exceptionally large positive thermal expansion and a negative thermal expansion in a perpendicular direction of the crystal. The consequent large shape change (~10%) of bulk material, with remarkable durability, suggests that this complex is a strong candidate as a microscale thermal actuating material.

7.
Chem Biol Drug Des ; 94(6): 2064-2072, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31444845

RESUMO

Neuropeptide Y4 receptor has the most significant effect on body weight and fat mass in its physiological functions, and the activation of Y4 receptor has explicit role on losing weight. The Y4 receptor has been successfully applied in the development of anti-obesity agent, thus representing a potential therapeutic target for obesity treatment. Here, we reported the first discovery of small molecule agonists targeting Y4 receptor: three Y4 receptor models with active and inactive conformations were built, each model was submitted following structure-based virtual screening, and finally six hits were identified as Y4 receptor agonists. These results confirm the reliability of the constructed Y4 receptor models and the proposed computational strategy for investigating novel Y4 receptor agonists. These new small molecule Y4 receptor agonists will contribute to the further development of Y4 agonists as potential therapeutics and functional probes.

9.
Org Lett ; 21(14): 5567-5569, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241967

RESUMO

A concise synthesis of the tricyclo[4.3.1.03,7]decane caged core of palhinine alkaloids was developed with SmI2-mediated cyclization and light-initiated radical addition-fragmentation as key steps. Compared with the reported racemic routes which are all based on Diels-Alder-type key reactions, our strategy would be more readily accessible to the asymmetric total syntheses of the palhinine alkaloids.

10.
Nanoscale Res Lett ; 14(1): 181, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31144185

RESUMO

The effect of nitridation treatment on the band alignment between few-layer MoS2 and HfO2 has been investigated by X-ray photoelectron spectroscopy. The valence (conduction) band offsets of MoS2/HfO2 with and without nitridation treatment were determined to be 2.09 ± 0.1 (2.41 ± 0.1) and 2.34 ± 0.1 (2.16 ± 0.1) eV, respectively. The tunable band alignment could be attributed to the Mo-N bonding formation and surface band bending for HfO2 triggered by nitridation. This study on the energy band engineering of MoS2/HfO2 heterojunctions may also be extended to other high-k dielectrics for integrating with two-dimensional materials to design and optimize their electronic devices.

11.
IEEE Trans Cybern ; 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30932857

RESUMO

This paper investigates the problem of designing event-triggered (ET) fuzzy controllers with varying gains for T-S fuzzy systems. New types of fuzzy controllers named ET fuzzy controllers with varying gains are proposed, in which the gains are automatically updated according to an online iteration algorithm at different triggering instants. By designing discontinuous Lyapunov function with time-varying Lyapunov matrix, sufficient conditions in terms of linear matrix inequalities (LMIs) are obtained to ensure the stability of the closed-loop system. It is shown that the proposed method achieves better system performances than the existing design methods with a quadratic Lyapunov function or ET fuzzy controllers with fixed gains. An example is provided to illustrate the effectiveness of the proposed method.

12.
Eur J Radiol ; 110: 97-104, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30599880

RESUMO

PURPOSE: To investigate the factors that could cause a misdiagnosis in virtual touch tissue imaging and quantification (VTIQ) when differentiating benign and malignant breast lesions, and to analyze the imaging characteristics of those lesions with incorrect findings. METHODS: The conventional ultrasound (CUS) features and the VTIQ parameters of 153 benign lesions and 99 malignant lesions were retrospectively analyzed and compared with histopathological and/or core-needle biopsy (CNB)-proven results. Independent variables that led to inaccurate VTIQ results were selected by binary logistic regression analysis. RESULTS: The maximum shear wave speed (SWS-max), the mean SWS (SWS-mean), the minimum SWS (SWS-min), the lesion-to-fat SWS ratio (SWS-L/F), and the lesion-to-gland SWS ratio (SWS-L/G) in malignant lesions were significantly higher than those in benign lesions (all P < 0.001). The false-positive rate (FPR) of benign lesions and the false-negative rate (FNR) of malignant lesions were 9.8% and 19.2%, respectively, using an SWS-max cut-off value of 4.46 m/s. Diameter, depth, and posterior acoustic features were independent variables related to false-positive VTIQ findings (P: 0.049, 0.010 and 0.032, respectively). The invasive status and the histologic grade of infiltrating carcinoma were significantly associated with false-negative VTIQ findings (P: 0.026 and 0.015). CONCLUSION: Diameter, depth, posterior acoustic features, invasive status, and histologic grade have a significant influence on the accuracy of VTIQ results, and these characteristics of breast lesions should be taken into account when interpreting the results of VTIQ examinations.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Erros de Diagnóstico , Técnicas de Imagem por Elasticidade/métodos , Adolescente , Adulto , Idoso , Biópsia com Agulha de Grande Calibre/normas , Feminino , Humanos , Pessoa de Meia-Idade , Exame Físico/normas , Estudos Retrospectivos , Adulto Jovem
13.
Acta Pharmacol Sin ; 40(6): 814-822, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30446732

RESUMO

Cancer cells always require more nutrients, energy, and biosynthetic activity to sustain their rapid proliferation than normal cells. Previous studies have shown the impact of THZ1, a covalent inhibitor of cyclin-dependent kinase 7 (CDK7), on transcription regulation and cell-cycle arrest in numerous cancers, but its effects on cellular metabolism in cancer cells remain unknown. In this study we elucidated the anticancer mechanism of THZ1 in human non-small-cell lung cancer (NSCLC) cells. We showed that treatment with THZ1 (10-1000 nM) dose-dependently suppressed the proliferation of human NSCLC cell lines H1299, A549, H292, and H23, and markedly inhibited the migration of these NSCLC cells. Furthermore, treatment with THZ1 (50 nM) arrested cell cycle at G2/M phase and induced apoptosis in these NSCLC cell lines. More importantly, we revealed that treatment with THZ1 (50 nM) blocked the glycolysis pathway but had no effect on glutamine metabolism. We further demonstrated that THZ1 treatment altered the expression pattern of glutaminase 1 (GLS1) isoforms through promoting the ubiquitination and degradation of NUDT21. Combined treatment of THZ1 with a glutaminase inhibitor CB-839 (500 nM) exerted a more potent anti-proliferative effect in these NSCLC cell lines than treatment with THZ1 or CB-839 alone. Our results demonstrate that the inhibitory effect of THZ1 on the growth of human NSCLC cells is partially attributed to interfering with cancer metabolism. Thus, we provide a new potential therapeutic strategy for NSCLC treatment by combining THZ1 with the inhibitors of glutamine metabolism.


Assuntos
Antineoplásicos/farmacologia , Fenilenodiaminas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Apoptose/efeitos dos fármacos , Benzenoacetamidas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quinases Ciclina-Dependentes/antagonistas & inibidores , Sinergismo Farmacológico , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Glutaminase/antagonistas & inibidores , Glicólise/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Tiadiazóis/farmacologia
14.
Neural Regen Res ; 14(1): 140-148, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30531088

RESUMO

Transient receptor potential ankyrin 1 (TRPA1) is a key player in pain and neurogenic inflammation, and is localized in nociceptive primary sensory dorsal root ganglion (DRG) neurons. TRPA1 plays a major role in the transmission of nociceptive sensory signals. The generation of neurogenic inflammation appears to involve TRPA1-evoked release of calcitonin gene-related peptide (CGRP). However, it remains unknown whether TRPA1 or CGRP expression is affected by TRPA1 activation. Thus, in this study, we examined TRPA1 and CGRP expression in DRG neurons in vitro after treatment with the TRPA1 activator formaldehyde or the TRPA1 blocker menthol. In addition, we examined the role of extracellular signal-regulated protein kinase 1/2 (ERK1/2) in this process. DRG neurons in culture were exposed to formaldehyde, menthol, the ERK1/2 inhibitor PD98059 + formaldehyde, or PD98059 + menthol. After treatment, real-time polymerase chain reaction, western blot assay and double immunofluorescence labeling were performed to evaluate TRPA1 and CGRP expression in DRG neurons. Formaldehyde elevated mRNA and protein levels of TRPA1 and CGRP, as well as the proportion of TRPA1- and CGRP-positive neurons. In contrast, menthol reduced TRPA1 and CGRP expression. Furthermore, the effects of formaldehyde, but not menthol, on CGRP expression were blocked by pretreatment with PD98059. PD98059 pretreatment did not affect TRPA1 expression in the presence of formaldehyde or menthol.

15.
Zhongguo Gu Shang ; 31(8): 735-739, 2018 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-30185008

RESUMO

OBJECTIVE: To evaluate the clinical effects of anterior segmental decompression for the treatment of multi-segment cervical spondylotic myelopathy. METHODS: The clinical data of 84 patients with multi-segment cervical spondylotic myelopathy treated between August 2005 to March 2016 were retrospectively analyzed. According to different operative methods the patients were divided into control group and observation group, with 42 cases in each group. In the control group, including 26 males and 16 females, the age was (56.87±11.89) years old and course of disease was(7.91±3.71) years on average, the lesion segment occurred on C3-C6 of 36 cases and on C4-C7 of 6 cases. There were 24 males and 18 females in observation group, with the mean age of (54.58±12.56) years old, and the course of disease was(8.03±3.52) years, the lesion segment occurred on C3-C6 of 34 cases, and on C4-C7 of 8 cases. The patients in control group were treated with posterior laminoplasty, and the patients in observation group underwent anterior segmental decompression. Operation time, intraoperative blood loss, hospitalization time, bone graft fusion time and complication rate were observed between two groups. JOA scores and Cobb angle of fusion segment were compared before operation and 3, 6, 9 months after operation. RESULTS: Operation time, intraoperative blood loss, hospitalization time and complication rate in observation group were significantly lower than in control group(P<0.05); the bone fusion time in observation group was significantly lower than in control group(P<0.01);3, 6, 9 months after surgery, JOA score and the segment Cobb angle in observation group were significantly higher than in control group(P<0.01). CONCLUSIONS: Anterior segmental decompression for the treatment of multi-segment cervical spondylotic myelopathy has obvious advantages of less vertebral resection, thorough decompression, good stability, less postoperative complications, which can effectively promote the recovery of the spinal cord function and vertebral stability.


Assuntos
Doenças da Medula Espinal , Fusão Vertebral , Espondilose , Adulto , Idoso , Vértebras Cervicais , Descompressão Cirúrgica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
16.
Ultrasound Med Biol ; 44(12): 2587-2595, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30174232

RESUMO

The objective of our study was to evaluate the association between the sonoelastography features of breast tumor and axillary lymph node metastasis (ALNM) in patients with breast cancer. In a cohort of 106 women with breast cancer, the conventional ultrasound features and elasticity parameters by elasticity imaging and Virtual Touch Tissue Imaging & Quantification (VTIQ) were retrospectively analyzed. Ultrasound and elastography findings were compared with pathologic axillary lymph node status. Receiver operating characteristic curve analysis was used to evaluate diagnostic performance. Pathologically, the overall incidence of ALNM was 39.6% (42/106) in the final analysis. ALNM was significantly more frequent in tumors with elasticity imaging scores >4.5, maximal shear wave velocity values (Smax) >6.42 m/s and mean shear wave velocity values (Smean) >5.66 m/s, respectively. The sensitivity, specificity and accuracy were 78.6%, 54.7% and 64.2% for elasticity imaging score; 85.7%, 54.7% and 67.0% for Smax; and 59.5%, 79.7% and 71.7% for Smean, respectively Elastography features, including elasticity imaging score and VTIQ, can be used to supplement conventional ultrasound to predict ALNM in patients with breast cancers.


Assuntos
Neoplasias da Mama/patologia , Técnicas de Imagem por Elasticidade/métodos , Linfonodos/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Cuidados Pré-Operatórios/métodos , Adulto , Idoso , Axila , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia/métodos
17.
Int J Med Mushrooms ; 20(2): 177-189, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29773009

RESUMO

Ganoderma mushrooms for medicinal use contain various bioactive compounds, but the genetic elements available for these medicinal mushrooms are still limited. In this study we cloned and analyzed the promoters of fungal immunomodulatory protein (FIP) genes from G. lucidum and G. atrum. FIP gene expression was induced by different concentrations of methyl jasmonate (MeJA) and salicylic acid (SA), and messenger RNA expression was detected by quantitative reverse-transcription polymerase chain reaction. The results provided 5' upstream sequences of FIP genes from G. lucidum and G. atrum. Sequence analysis showed that the FIP-glu promoter sequence contained 11 CAAT boxes, 3 TATA boxes, 3 MeJA-responsive elements, 3 MYB binding site (MBS) motifs, 1 abscisic acid responsive element, 1 TGA, 1 anaerobic inducible element, 2 circadian elements, 1 fungal elicitor, 1 meristem-specific activation element, 3 Skn-1 motifs, and several light-responsive elements. The 5' flanking region of FIP-gat included 9 CAAT boxes, 4 TATA boxes, 3 MeJA-responsive elements, 1 AuxRR core, 1 GC motif, 1 MBS, 1 fungal elicitor, 1 meristem-specific activation element, 3 Skn-1 motifs, and several light-responsive elements. On the transcriptional level, both FIP-glu and FIP-gat reached their highest expression after treatment with MeJA at 500 µmol/L. FIP-glu expression depended on the concentration of SA (0-1000 mg/L); the expression of the FIP-gat gene was highest at a concentration of 100 mg MeJA/L. This research lays the foundation to use Ganoderma mycelia as bioreactors for producing FIPs.


Assuntos
Proteínas Fúngicas/genética , Ganoderma/genética , Regulação Fúngica da Expressão Gênica , Fatores Imunológicos/genética , Regiões Promotoras Genéticas/genética , Acetatos/farmacologia , Antifúngicos/farmacologia , Sequência de Bases , Sítios de Ligação , Clonagem Molecular/métodos , Ciclopentanos/farmacologia , Genes Fúngicos , Oxilipinas/farmacologia , Ácido Salicílico/farmacologia , Análise de Sequência de DNA
18.
Clin Hemorheol Microcirc ; 70(1): 39-50, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29660916

RESUMO

OBJECTIVES: To compare the diagnostic performance of conventional strain elastography (CSE) and acoustic radiation force impulse (ARFI) induced SE for qualitative assessment of breast lesions and evaluate the additional value of the two techniques combined with Breast Imaging Reporting and Data System (BI-RADS) respectively for the differentiation of benign and malignant breast lesions. METHODS: In a cohort of 110 women, the conventional ultrasound (US) features and the elasticity scores of CSE and ARFI induced SE were recorded. The diagnostic performances of BI-RADS, elastography and BI-RADS plus elastography were evaluated, including the area under the receiver operating characteristic curve (AUROC), sensitivity, specificity and accuracy. RESULTS: Pathologically, there were forty-eight malignant and sixty-two benign breast lesions in the final analysis. The AUCs for CSE and ARFI induced SE are similar (CSE, 0.807; ARFI induced SE, 0.846; p > 0.05), however, the specificity of the latter method was significantly higher than that of CSE (83.9% vs. 58.1%, p = 0.004) in differentiating breast lesions. The accuracy and specificity of BI-RADS plus ARFI induced SE (84.5%, 80.6%, respectively) were significantly higher than BI-RADS alone (73.6%, 54.8%, respectively) and BI-RADS plus conventional SE (72.7%, 56.5%, respectively), respectively (p < 0.05) without loss of sensitivity. CONCLUSIONS: Our study showed that BI-RADS plus ARFI induced SE had a better diagnostic performance in the diagnosis of breast lesions in comparison with BI-RADS alone or BI-RADS plus CSE.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Ultrassonografia Mamária/métodos , Ultrassonografia/métodos , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
ISA Trans ; 76: 18-30, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29503010

RESUMO

This paper is concerned with the design of piecewise fuzzy diagnostic observers for discrete-time T-S fuzzy systems under an event-triggered (ET) communication mechanism. Considering that the premise variables of the fuzzy diagnostic observer and the system may belong to different local space regions due to the introduction of ET mechanism, a partition method-based piecewise fuzzy diagnostic observer is designed to detect faults. The two-term approximation approach is introduced to approximate the time-varying delay. By transforming the augmented system into an input-output form consisting of two interconnected subsystems, the design condition of the piecewise fuzzy diagnostic observer is obtained by using the scaled small gain (SSG) theorem and a piecewise Lyapunov-Krasovskii functional. Furthermore, the L∞/L2 and L∞ fault detection (FD) scheme is used to optimize the FD performance. Finally, two simulation examples are provided to show the efficiency of the proposed design method.

20.
Chem Cent J ; 12(1): 20, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29476294

RESUMO

The molecular docking method was used to calculate the binding free energies between biphenyl dioxygenase and 209 polychlorinated biphenyl (PCB) congeners. The relationships between the calculated binding free energies and migration (octanol-air partition coefficients, KOA), persistence (half-life, t1/2), toxicity (half maximal inhibitory concentration, IC50), and bioaccumulation (bioconcentration factor, BCF) values for the PCBs were used to gain insight into the degradation of PCBs in the presence of biphenyl dioxygenase. The relationships between the calculated binding free energies and the molecular weights, KOA, BCF, and t1/2 values for the PCBs were statistically significant (P < 0.01), whereas the relationship between the calculated binding free energies and the IC50 for the PCBs was not statistically significant (P > 0.05). The electrostatic field, derived from three-dimensional quantitative structure-activity relationship studies, was a primary factor governing the binding free energy, which agreed with literature findings for KOA, t1/2, and BCF. Comparative molecular field analysis and comparative molecular similarity indices analysis contour maps showed that the binding free energies, KOA, t1/2, and BCF values for the PCBs decreased simultaneously when substituents with electropositive groups at the 3-position or electronegative groups at the 3'-position were introduced. This indicated the binding free energy was correlated with the persistent organic pollutant characteristics of PCBs. Furthermore, low binding free energies improved the degradation of the PCBs and simultaneously decreased the KOA, t1/2, and BCF values, thereby reducing the persistent organic pollutant characteristics of PCBs in the environment. These results are expected to be beneficial in providing a theoretical foundation for further elucidation of the degradation and molecular modification of PCBs.

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