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1.
Opt Express ; 31(25): 41887-41904, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38087576

RESUMO

We propose and demonstrate an improved quantum illumination protocol based on the time correlation of twin photons, for the high signal-to-noise ratio (SNR) of target detection and signal reconstruction in the strong noise environment. The Hong-Ou-Mandel (HOM) interferometer is applied after the spontaneous parametric down-conversion (SPDC) process to construct a probing twin-beam in which the photon times are precisely aligned between the beams. At the radar receiver, we put forward a single real-time coincidence counting (SRCC) method on a series of time slices to reconstruct the probe signals of pulse radar and calculate the SNR advantages against the conventional pulse radar, as well as the quantum illumination (QI) protocol. Our main achievements in this research are the realization of real-time detection of quantum information while acquiring a higher SNR than QI and classical illumination (CI) protocols, as well as its demonstration of strong robustness to noise and losses, which also proposes what we believe to be a novel way for quantum target detection.

2.
Nanomaterials (Basel) ; 13(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36839085

RESUMO

Nanoscale composite energetic materials (CEMs) based on oxidizer and fuel have potential advantages in energy adjustment and regulation through oxygen balance (OB) change. The micro- and nanosized fibers based on nano nitrocellulose (NC)-ammonium dinitramide (ADN) were prepared by the electrospinning technique, and the morphology, thermal stability, combustion behaviors, and mechanical sensitivity of the fibers were characterized by means of scanning electron microscope (SEM), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), gas pressure measurement of thermostatic decomposition, laser ignition, and sensitivity tests. The results showed that the prepared fibers with fluffy 3D macrostructure were constructed by the overlap of micro/nanofibers with the energetic particles embedded in the NC matrix. The first exothermic peak temperature (Tp) of the samples containing ADN decreased by 10.1 °C at most compared to that of ADN, and the pressure rise time of all the samples containing ADN moved forward compared to that of the sample containing NC only. Furthermore, ADN can decrease the ignition delay time of NC-based fibers under atmosphere at room temperature from 33 ms to 9 ms and can enhance the burning intensity of NC-based fibers under normal pressure. In addition, compared to the single high explosive CL-20 or RDX, the mechanical sensitivities of the composite materials containing high explosive CL-20 or RDX were much decreased. The positive oxygen balance of ADN and the intensive interactions between ADN and NC can reduce the ignition delay time and promote the burning reaction intensity of NC-based composite fibers, while the mechanical sensitivities of composite fibers could be improved.

3.
Sensors (Basel) ; 19(4)2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30791600

RESUMO

Hough Transform (HT), which has a low sensitivity to local faults and good ability in suppressing noise and clutters, usually applies to trajectory detection in a cluttered environment. This paper describes its application for detecting the trajectories of extended targets in three-dimensional measurements, i.e., a two-dimensional positional information and its measuring time. For taking the full merits of a multi-scan, the measuring time is regarded as a variable for the time axis. This correspondence extends the HT to 3-dimensional data. Meanwhile, a three-dimensional accumulator matrix is built for the purpose of voting. The voting process is done in an iterative way by selecting the 3D-line with the most votes and removing the corresponding measurements in each step. The three dimensional Hough Transform-based extended target track-before-detect technique (3DHT-ET-TBD), proposed here, is suitable to track the extended target and non-extended target simultaneously and few false alarm trajectories arise. Both the real data and simulated data are exploited to evaluate its performance. Compared with the Gaussian Mixture Probability Hypothesis Density (GM-PHD) filter based methods and a 4DHT-TBD algorithm, the 3DHT-ET-TBD is a more promising approach for multi-extended target tracking problems due to its high efficiency and low computation, especially in situations where the noise and false alarms are considerably high but few measurements are generated by the extended targets.

4.
Oncol Rep ; 35(4): 1941-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26782786

RESUMO

5-Aza-2'-deoxycytidine (5-Aza-CdR) is currently acknowledged as a demethylation drug, and causes a certain degree of demethylation in a variety of cancer cells, including pancreatic cancer cells. Emodin, a traditional Chinese medicine (TCM), is an effective monomer extracted from rhubarb and has been reported to exhibit antitumor activity in different manners in pancreatic cancer. In the present study, we examined whether emodin caused demethylation and increased the demethylation of three tumor-suppressor genes P16, RASSF1A and ppENK with a high degree of methylation in pancreatic cancer when combined with 5-Aza-CdR. Our research showed that emodin inhibited the growth of pancreatic cancer Panc-1 cells in a dose- and time-dependent manner. Dot-blot results showed that emodin combined with 5-Aza-CdR significantly suppressed the expression of genome 5mC in PANC-1 cells. In order to verify the effect of methylation, methylation-specific PCR (MSP) and bisulfite genomic sequencing PCR (BSP) combined with TA were selected for the cloning and sequencing. Results of MSP and BSP confirmed that emodin caused faint demethylation, and 5-Aza-CdR had a certain degree of demethylation. When emodin was combined with 5-Aza-CdR, the demethylation was more significant. At the same time, fluorescent quantitative PCR and western blot analysis results confirmed that when emodin was combined with 5-Aza-CdR, the expression levels of P16, RASSF1A and ppENK were increased more significantly compared to either treatment alone. In contrast, the expression levels of DNA methyltransferase 1 (DNMT1) and DNMT3a were more significantly reduced with the combination treatment than the control or either agent alone, further proving that emodin in combination with 5-Aza-CdR enhanced the demethylation effect of 5-Aza-CdR by reducing the expression of methyltransferases. In conclusion, the present study confirmed that emodin in combination with 5-Aza-CdR enhanced the demethylation by 5-Aza-CdR of tumor-suppressor genes p16, RASSF1A and ppENK by reducing the expression of methyltransferases DNMT1 and DNMT3a.


Assuntos
Azacitidina/análogos & derivados , Metilação de DNA/efeitos dos fármacos , Emodina/farmacologia , Encefalinas/genética , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/genética , Precursores de Proteínas/genética , Proteínas Supressoras de Tumor/genética , Azacitidina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor p16 de Quinase Dependente de Ciclina , Decitabina , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Regiões Promotoras Genéticas/efeitos dos fármacos , Análise de Sequência de DNA/métodos
5.
Tumour Biol ; 36(9): 7069-75, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25869877

RESUMO

We examined microRNA (miRNA)-10b expression in peripheral blood mononuclear cells (PBMCs) of nonsmall-cell lung cancer (NSCLC) patients for its clinical value. A group of 74 patients confirmed with NSCLC were recruited as case group and 52 healthy volunteers as control group. PBMCs were isolated from all subjects, and miRNA-10b expression level in these cells was measured by reverse transcription quantitative real-time polymerase chain reaction (qRT-PCR). The correlation between miRNA-10b expression levels and the clinical and pathological characteristics of NSCLC was obtained. The miRNA-10b expression level in NSCLS patients is markedly higher than control subjects (P < 0.01). Analysis of receiver operating characteristic (ROC) curve estimated the peak diagnostic sensitivity of miRNA-10b at 86.5 % and specificity at 76.9 %. NSCLC patients were divided into high expression group (64 patients) and low expression group (10 patients). Further analysis showed that miRNA-10b expression levels in PBMCs correlated with lymph node metastasis, distant metastasis, and TNM classification (all P < 0.05). The 5-year survival rate in high expression group was significantly lower than low expression group (P = 0.017). Multivariate analysis by Cox regression model showed that high miRNA-10b expression, age >60 years, lymph node and distant metastases, and stage III-IV carcinoma were risk factors for poor prognosis in NSCLC patients (all P < 0.05). MiRNA-10b expression levels in PBMCs can distinguish NSCLC patients from cancer-free subjects with a high sensitivity and specificity, suggesting that miRNA-10b expression in PBMCs is a valuable diagnostic and prognostic marker in NSCLC.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/genética , MicroRNAs/biossíntese , Adulto , Idoso , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Leucócitos Mononucleares/patologia , Metástase Linfática , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
6.
Zhonghua Yi Xue Za Zhi ; 91(26): 1852-5, 2011 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-22093790

RESUMO

OBJECTIVE: To establish the serial cell lines, derived from the same parental gallbladder cancer cell line GBC-SD, with highly metastatic potential via different routes and characterize their biological behaviors to understand the different metastasis mechanisms via lymph and blood. METHODS: The spleen-liver metastasis model and footpad-inguinal lymph node metastasis model were established. GBC-SD was injected into spleen or footpad of nude mice. Then the highly metastasized subpopulations via lymph and blood were isolated. Their differences in morphology, genetic background, proliferation, migration, invasion and adhesion were revealed by comparing the lymphatic-disseminating and hematogenous-disseminating subpopulations with parental cells. RESULTS: The lymphatic-disseminating and hematogenous-disseminating subpopulations were successfully isolated and designated as GBC-SD/HL and GBC-SD/M3 respectively. They demonstrated the identical genetic background with GBC-SD. In comparison with parental cells, the hematogenous-disseminating subpopulation was morphologically characterized with epithelial-mesenchymal transition (EMT) while it was not shown in the lymphatic-disseminating subpopulation. Furthermore, the hematogenous-disseminating subpopulation showed the strongest migrating capacity but the lymphatic-disseminating subpopulation demonstrated a stronger invasive and adhesive ability. CONCLUSION: The whole parental cell GBC-SD, hematogenous-metastasized subpopulation GBC-SD/M3 and lymphatic-disseminating subpopulation GBC-SD/HL is an ideal tool for metastatic mechanism study of gallbladder cancer. EMT plays an important role in hematogenous metastasis while lymphatic metastasis relies more on enhanced invasiveness and adhesion. It may be a target for interfering the lymphatic metastasis of gallbladder cancer.


Assuntos
Linhagem Celular Tumoral , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/secundário , Animais , Humanos , Neoplasias Hepáticas/patologia , Linfonodos/patologia , Metástase Linfática/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias
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