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1.
Front Oncol ; 12: 837413, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356225

RESUMO

Background: Cough is one of the most common complications of early-stage non-small cell lung cancer (NSCLC) after video-assisted thoracoscopic surgery (VATS). The vagus nerve plays an important role in pulmonary inflammation and the cough reflex. In this study, we attempted to reduce the incidence of postoperative chronic cough and other complications by preserving the pulmonary vagus nerve branches. Patients and Methods: This study was a randomized controlled double-blinded trial of subjects and observers. A total of 158 NSCLC patients were enrolled. We randomly assigned 79 patients to Group A (pulmonary branch of vagus nerve preservation group) and 79 cases to Group B (conventional surgical treatment group). In the final analysis, 72 patients from Group A and 69 patients from Group B were included. The main outcome measure of the study was the occurrence of CAP or other postoperative complications within five weeks. This trial was registered with ClinicalTrials.gov (number NCT03921828). Results: There was no significant difference in preoperative general clinical data between the two groups. No death during the perioperative period occurred in either of the two groups. There was no significant difference between the two groups in operation time, intraoperative bleeding, number of lymph nodes sent for examination, number of cases transferred to ICU after operation, postoperative catheterization time, or postoperative hospital stay (P>0.05). There was no significant difference in other pulmonary and cardiovascular complications between the two groups, including pulmonary infection (2.78% vs. 8.70%, P = 0.129), atelectasis (1.39% vs. 0%, P = 0.326), pleural effusion (2.78% vs. 1.45%, P = 0.585), persistent pulmonary leakage (2.78% vs. 2.90%, P = 0.965), arrhythmia (2.78% vs. 1.45%, P = 0.585), and heart failure (0% vs. 1.45%, P = 0.305). The incidence of CAP in Group A was significantly lower than that in Group B (13.89% vs. 30.43%, P = 0.018). The LCQ-MC scores in Group A were significantly higher than those in Group B at two and five weeks after operation (P<0.05). Univariate and multivariate analysis showed that the risk factors for postoperative CAP were surgical side (right lung), surgical lung lobe (upper lobe), preservation of pulmonary branch of the vagus nerve during operation, and duration of anesthesia. Conclusions: Preserving the pulmonary vagus nerve branches during VATS in patients with stage IA1-2 NSCLC can reduce the incidence of postoperative CAP.

2.
Clin Transl Med ; 11(9): e545, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34586732

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a highly aggressive and treatment-resistant tumor. The biological implications and molecular mechanism of cancer stem-like cells (CSCs) in ESCC, which contribute to therapeutic resistance such as radioresistance, remain elusive. METHODS: Quantitative real-time polymerase chain reaction, western blotting, immunohistochemistry, and in situ hybridization assays were used to detect methyltransferase-like 14 miR-99a-5p tribble 2 (METTL14/miR-99a-5p/TRIB2) expression in ESCC. The biological functions of METTL14/miR-99a-5p/TRIB2 were demonstrated in vitro and in vivo. Mass spectrum analysis was used to identify the downstream proteins regulated by TRIB2. Chromatin immunoprecipitation (IP), IP, N6 -methyladenosine (m6 A)-RNA IP, luciferase reporter, and ubiquitination assays were employed to explore the molecular mechanisms underlying this feedback circuit and its downstream pathways. RESULTS: We found that miR-99a-5p was significantly decreased in ESCC. miR-99a-5p inhibited CSCs persistence and the radioresistance of ESCC cells, and miR-99a-5p downregulation predicted an unfavorable prognosis of ESCC patients. Mechanically, we unveiled a METTL14-miR-99a-5p-TRIB2 positive feedback loop that enhances CSC properties and radioresistance of ESCC cells. METTL14, an m6 A RNA methyltransferase downregulated in ESCC, suppresses TRIB2 expression via miR-99a-5p-mediated degradation of TRIB2 mRNA by targeting its 3' untranslated region, whereas TRIB2 induces ubiquitin-mediated proteasomal degradation of METTL14 in a COP1-dependent manner. METTL14 upregulates miR-99a-5p by modulating m6 A-mediated, DiGeorge critical region 8-dependent pri-mir-99a processing. Hyperactivation of TRIB2 resulting from this positive circuit was closely correlated with radioresistance and CSC characteristics. Furthermore, TRIB2 activates HDAC2 and subsequently induces p21 epigenetic repression through Akt/mTOR/S6K1 signaling pathway activation. Pharmacologic inhibition of HDAC2 effectively attenuates the TRIB2-mediated effect both in vitro and in patient-derived xenograft models. CONCLUSION: Our data highlight the presence of the METTL14/miR-99a-5p/TRIB2 axis and show that it is positively associated with CSC characteristics and radioresistance of ESCC, suggesting potential therapeutic targets for ESCC treatment.


Assuntos
Epigênese Genética/genética , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Células-Tronco Neoplásicas/metabolismo , Tolerância a Radiação/genética , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Feminino , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Humanos , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , MicroRNAs/metabolismo
3.
J Hazard Mater ; 378: 120711, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202070

RESUMO

Ethanol gasoline is being widely used as a new environmentally friendly and energy-saving alternative energy, and the control/reduction of its fire/explosion risk has become an important aspect, not only for its production and storage, but also for its transport and application. This study aims to investigate the explosion characteristics of ethanol gasoline and its mitigation using heptafluoropropane in a restricted vessel. The flame propagation was visualized using a Phantom high-speed camera at 3000 fps, the explosion overpressure was measured using PCB pressure sensors, and the gas released from the vent was collected and analyzed using a gas chromatography-mass spectrometer. The results indicate that heptafluoropropane has a good suppression effect on the flame propagation speed and the explosion overpressure. The maximum overpressure of an ethanol gasoline explosion is approximately 456 kPa, and the overpressure reduction exceeds 60% when the concentration of heptafluoropropane addition is 10%, whereas an explosion is completely mitigated when the concentration of heptafluoropropane continuously increases. In addition, different flame colors during the mitigation process, such as blue, yellow, and purple, were observed and analyzed. The results of this study will be valuable for further understanding ethanol gasoline explosion mitigation and designing optimum heptafluoropropane explosion mitigation systems.

4.
Entropy (Basel) ; 22(1)2019 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33285806

RESUMO

Due to the uncertainty of radar target prior information in actual scenes, waveform design based on radar target prior information cannot meet the requirements of detection performance and parameter estimation. Aiming at the problem of waveform design for detecting multi-target in the presence of clutter, a linear probability-weighted summation (PWS) algorithm based on multi-target impulse response is proposed and includes the radar waveform design based on mutual information (MI) and signal-to-interference ratio (SINR) criteria. In view of the traditional water-filling algorithm, the problem of multi-target is further investigated in a new way to improve the overall performance of the system. The method makes a lot of deductions by using Jensen's inequality, to determine the algorithm objective function and energy constraint. The simulation results show that the proposed algorithm has better detection performance and more accurate target information.

5.
J Hazard Mater ; 341: 20-27, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28763633

RESUMO

A new type of dry powders with capsular structure was fabricated for fire suppression, in which the content of water approached 60%. The capsules with the size of 3-5µm consisted of liquid core and solid shell, where the core was water droplet and the shell was assembled silicon dioxide particles with surface hydrophobic modification. The shell of close-packed silica particles surrounding each water droplet provided the structural rigidity of the capsules and enabled their application as powder fire suppressants. Two different scaled real fire tests showed that thus-prepared solid powders could extinguish 0.21MW gasoline pool fire in 2.0s with agent mass of 0.055kg, and 1.0MW gasoline pool fire in 5.0s with agent mass of 0.49kg. Such fire extinguishing performance greatly outperformed the conventional monoammonium phosphate (ABC) powders, neat silica powders and water mist, with significantly reduced fire extinguishing time and mass of agent consumed. Mechanism of the core-shell particles in fire suppression was discussed based on established theories and experimental results.

6.
J Hazard Mater ; 342: 231-241, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28841470

RESUMO

The hazards of the spread of fire smoke in a channel have been recognized. This paper relates to the potential use of a water mist curtain (WMC) for preventing the spread of fire smoke, focusing particularly on smoke control at the early stage of a fire, with the aim of reducing the harm of fire smoke and allowing time for people to escape. Fatal factors for occupant evacuation in a fire, such as carbon monoxide concentration, smoke temperature, and visibility, were measured in the section controlled by the WMC. The results indicate that the WMC can be effective in preventing fire smoke from spreading at the early stage, and may provide a useful reference for developing a novel method of smoke control. Furthermore, the effects of nozzles with different spray characteristics were investigated and an optimal working pressure was suggested. In addition, a mathematical model was simplified and used to analyze the interaction between the fire-induced smoke layer and WMC spray.

7.
Phys Rev Lett ; 114(5): 050502, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25699427

RESUMO

Constructing a quantum memory for a photonic entanglement is vital for realizing quantum communication and network. Because of the inherent infinite dimension of orbital angular momentum (OAM), the photon's OAM has the potential for encoding a photon in a high-dimensional space, enabling the realization of high channel capacity communication. Photons entangled in orthogonal polarizations or optical paths had been stored in a different system, but there have been no reports on the storage of a photon pair entangled in OAM space. Here, we report the first experimental realization of storing an entangled OAM state through the Raman protocol in a cold atomic ensemble. We reconstruct the density matrix of an OAM entangled state with a fidelity of 90.3%±0.8% and obtain the Clauser-Horne-Shimony-Holt inequality parameter S of 2.41±0.06 after a programed storage time. All results clearly show the preservation of entanglement during the storage.

8.
Opt Express ; 22(17): 20298-310, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25321240

RESUMO

Light with helical phase structures, carrying quantized orbital angular momentum (OAM), has many applications in both classical and quantum optics, such as high-capacity optical communications and quantum information processing. Frequency conversion is a basic technique to expand the frequency range of the fundamental light. The frequency conversion of OAM-carrying light gives rise to new physics and applications such as up-conversion detection of images and generation of high dimensional OAM entanglements. Quasi-phase matching (QPM) nonlinear crystals are good candidates for frequency conversion, particularly due to their high-valued effective nonlinear coefficients and no walk-off effect. Here we report the first experimental second-harmonic generation (SHG) of an OAM-carried light with a QPM crystal, where a UV light with OAM of 100 ℏ is generated. OAM conservation is verified using a specially designed interferometer. With a pump beam carrying an OAM superposition of opposite sign, we observe interesting interference phenomena in the SHG light; specifically, a photonics gear-like structure is obtained that gives direct evidence of OAM conservation, which will be very useful for ultra-sensitive angular measurements. Besides, we also develop a theory to reveal the underlying physics of the phenomena. The methods and theoretical analysis shown here are also applicable to other frequency conversion processes, such as sum frequency generation and difference-frequency generation, and may also be generalized to the quantum regime for single photons.

9.
J Hazard Mater ; 260: 552-62, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23811377

RESUMO

The effects of downward airflow on the burning rate and/or burning intensity of square alcohol pool fires for different airflow speeds and directions have been studied experimentally in an inclined wind tunnel. An interesting flame-wrapping phenomenon, caused by impingement of air flow, was observed. The mass burning intensity was found to increase with the airflow speed and the impinging angle. The fuel pan rim temperatures were also measured to study the effect of wind direction and speed on heat transfer from the flame to the fuel source. A model based on heat transfer analysis was developed to correlate the burning intensity with the pan rim characteristic temperature. A good correlation was established between the model results and the experimental results.


Assuntos
Etanol/química , Incêndios , Vento , Ar , Gases , Temperatura Alta , Temperatura , Fatores de Tempo
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 25(1): 101-4, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18435267

RESUMO

In this paper, a biodynamic model of human upper-body in the seated posture is developed. Based on d'Alembert's principle, the non-linear biodynamic equation of the modelling is derivated. Furthermore, the function of frequency and amplitude of modelling is obtained by employing the KB method in the non-linear theory. The response of realistic human parameters and the external stimulus on the modelling is simulated by MATLAB. The results show that the modelling presents a plenty of non-linear characteristics. The parameters identified and the stable areas to keep the stabilization of upper-body in the seated posture are discussed. These data can be used to explain and estimate the mechanism for the maintenance of stable trunk posture due to the mechanical shocks transmitted through the vehicle seat.


Assuntos
Modelos Biológicos , Postura/fisiologia , Coluna Vertebral/fisiologia , Vibração , Condução de Veículo , Fenômenos Biomecânicos , Humanos , Dor Lombar/etiologia , Dinâmica não Linear
11.
Appl Opt ; 44(22): 4648-53, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16075876

RESUMO

An optical diagnostic technique has been developed to measure the gas-liquid interfacial film thickness in microcapillary two-phase flows. The spatial frequencies from the multiscattering measured with a CCD camera are used to determine the slug diameter and film thickness. It is found that, with an optimized optical orientation angle, the spatial frequency method shows great accuracy in the measurements. To demonstrate the capability of the newly developed method, a validation experiment was conducted in water-air and water-honey mixture-air two-phase flows. We measured the spatial frequency variations when the microbubble and slug were pulsating by utilizing a highly accurate signal processing technique and a five-point interpolation method. This newly developed optical method is easy to implement, and it will be a useful technique for two-phase flow measurements.

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