1,598 research outputs found
Effect of Qufeng Xuanbi Formula on experimental asthma guinea pigs' airway inflammation and Th1/Th2 cytokines
目的 观察祛风宣痹方对哮喘豚鼠气道炎症和Th1/Th2细胞因子的影响,探讨其作用机制。方法 用卵蛋白和雾化吸入致敏法,复制豚鼠哮喘模型;取肺泡灌洗液进行嗜酸性粒细胞(Eos)计数;肺组织切片HE染色形态学观察;ELASA方法检测BALF中IFN-γ和IL-4的含量。结果 模型组较正常组肺泡灌洗液(BALF)中气道Eos炎症细胞表达异常,组织形态学病变明显,IFN-γ含量显著下降,IL-4的含量明显升高;地塞迷松米组、中药高剂量组、中药低剂量组较模型组均有显著性差异,BALF中Eos的数量明显降低,组织形态学改善明显,IFN-γ含量显著升高,IL-4的含量明显下降,中药高剂量组效果强于低剂量组。结论 祛风宣痹方能减少EOS浸润,抑制气道炎症,调节Th1/Th2失衡,这可能是其阻断哮喘发生发展的机制之一。Objective: To explore the therapeutic effect and mechanism of Qufeng Xuanbi Formula on experimental asthma guinea pigs' airway inflammation and regulation Th1/Th2 imbalance in treatment of bronchia asthma. Methods: Animal models were established in guinea pigs by a combination of intraperitional injection and repeated intranasal challenges. Immune adjustment influence of medicine on Th1/Th2 imbalance was observed.Eos in BALF were counted and tissue slice dyed with HE were observed; Content of IFN-γand IL-4 were detected by ELASA. Results: Compared with normal group, the alveolar lavage fluid (BALF) in the marked increase in the number of Eos, histomorphology lesions, obviously abnormal Eos of the airway inflammatory cells express; the level of IFN-γwas dramatically decreased, neutrophil and level of IL- 4 were all significantly increased in the BALF. DXM group, high and low dose group are significant different compared with model group (P<0.01), However, the percentages of EOS and level of IFN-γwas dramatically increased, the level of IL-4 was dramatically decreased (P<0.01), high dose group‘s effect is better than the low dose group. Conclusion: Qufeng Xuanbi Formula can reduce the EOS infiltration, inhibit airway inflammation, regulate Th1/Th2 imbalance, it could be one of the blocking mechanism of occurrence and development of asthma.
E-UAV: An Edge-based Energy-Efficient Object Detection System for Unmanned Aerial Vehicles
Motivated by the advances in deep learning techniques, the application of
Unmanned Aerial Vehicle (UAV)-based object detection has proliferated across a
range of fields, including vehicle counting, fire detection, and city
monitoring. While most existing research studies only a subset of the
challenges inherent to UAV-based object detection, there are few studies that
balance various aspects to design a practical system for energy consumption
reduction. In response, we present the E-UAV, an edge-based
energy-efficient object detection system for UAVs. The system is designed to
dynamically support various UAV devices, edge devices, and detection
algorithms, with the aim of minimizing energy consumption by deciding the most
energy-efficient flight parameters (including flight altitude, flight speed,
detection algorithm, and sampling rate) required to fulfill the detection
requirements of the task. We first present an effective evaluation metric for
actual tasks and construct a transparent energy consumption model based on
hundreds of actual flight data to formalize the relationship between energy
consumption and flight parameters. Then we present a lightweight
energy-efficient priority decision algorithm based on a large quantity of
actual flight data to assist the system in deciding flight parameters. Finally,
we evaluate the performance of the system, and our experimental results
demonstrate that it can significantly decrease energy consumption in real-world
scenarios. Additionally, we provide four insights that can assist researchers
and engineers in their efforts to study UAV-based object detection further.Comment: 16 pages, 8 figure
Receptor Specificity Engineering of TNF Superfamily Ligands
The tumor necrosis factor (TNF) ligand family has nine ligands that show promiscuity in binding multiple receptors. As different receptors transduce into diverse pathways, the study on the functional role of natural ligands is very complex. In this review, we discuss the TNF ligands engineering for receptor specificity and summarize the performance of the ligand variants in vivo and in vitro. Those variants have an increased binding affinity to specific receptors to enhance the cell signal conduction and have reduced side effects due to a lowered binding to untargeted receptors. Refining receptor specificity is a promising research strategy for improving the application of multi-receptor ligands. Further, the settled variants also provide experimental guidance for engineering receptor specificity on other proteins with multiple receptors
Artemisinin-Type Drugs in Tumor Cell Death:Mechanisms, Combination Treatment with Biologics and Nanoparticle Delivery
Artemisinin, the most famous anti-malaria drug initially extracted from Artemisia annua L., also exhibits anti-tumor properties in vivo and in vitro. To improve its solubility and bioavailability, multiple derivatives have been synthesized. However, to reveal the anti-tumor mechanism and improve the efficacy of these artemisinin-type drugs, studies have been conducted in recent years. In this review, we first provide an overview of the effect of artemisinin-type drugs on the regulated cell death pathways, which may uncover novel therapeutic approaches. Then, to overcome the shortcomings of artemisinin-type drugs, we summarize the recent advances in two different therapeutic approaches, namely the combination therapy with biologics influencing regulated cell death, and the use of nanocarriers as drug delivery systems. For the former approach, we discuss the superiority of combination treatments compared to monotherapy in tumor cells based on their effects on regulated cell death. For the latter approach, we give a systematic overview of nanocarrier design principles used to deliver artemisinin-type drugs, including inorganic-based nanoparticles, liposomes, micelles, polymer-based nanoparticles, carbon-based nanoparticles, nanostructured lipid carriers and niosomes. Both approaches have yielded promising findings in vitro and in vivo, providing a strong scientific basis for further study and upcoming clinical trials
Propagation of instability in dielectric elastomers
AbstractWhen an electric voltage is applied across the thickness of a thin layer of an dielectric elastomer, the layer reduces its thickness and expands its area. This electrically induced deformation can be rapid and large, and is potentially useful as soft actuators in diverse technologies. Recent experimental and theoretical studies have shown that, when the voltage exceeds some critical value, the homogenous deformation of the layer becomes unstable, and the layer deforms into a mixture of thin and thick regions. Subsequently, as more electric charge is applied, the thin regions enlarge at the expense of the thick regions. On the basis of a recently formulated nonlinear field theory, this paper develops a meshfree method to simulate numerically this instability
Fibre laser torsion sensor system using an excessively tilted fibre grating and low-cost time domain demodulation
In this paper, we report a simple fibre laser torsion sensor system using an intracavity tilted fibre grating as a torsion encoded loss filter. When the grating is subjected to twist, it induces loss to the cavity, thus affecting the laser oscillation build-up time. By measuring the build-up time, both twist direction and angle on the grating can be monitored. Using a low-cost photodiode and a two-channel digital oscilloscope, we have characterised the torsion sensing capability of this fibre laser system and obtained a torsion sensitivity of ~412µs/(rad/m) in the dynamic range from -150° to +150°
800 nm WDM interrogation system for strain, temperature, and refractive index sensing based on tilted fiber Bragg grating
A low-cost high-resolution wavelength-division-multiplexing (WDM) interrogation system operating around 800 nm region with operational bandwidth up to 60 nm and resolution of 12.7 pm utilizing a tilted fiber Bragg grating (TFBG) and a CCDarray detector has been implemented. The system has been evaluated for interrogating fiber Bragg grating based strain, temperature sensors, giving sensitivities of 0.59 pm/µe and 5.6 pm/°C, which are in good agreement with previously reported values. Furthermore, the system has been utilized to detect the refractive index change of sample liquids, demonstrating a capability of measuring index change as small as 10¯5. In addition, the vectorial expression of phase match condition and fabrication of TFBG have been discussed
Polarisation mode coupling of excessively tilted fibre Bragg gratings with directional transverse loading
We report a distinctive polarisation mode coupling behaviour of tilted fibre Bragg gratings (TFBGs) with tilted angle exceeding 45°. The ex-45° TFBGs exhibit pronounced polarisation mode splitting resulted from grating structure asymmetry induced birefringence. We have studied and analysed the property of ex-45° TFBGs under transverse load applied to their equivalent fast- and slow-axis. The results show that the coupling between the orthogonally polarised modes takes place only when the load is applied to its fast-axis, giving a prominent directional loading response. This transverse load related polarisation property may be exploitable for implementation of optical fibre vector sensors capable of measuring the magnitude and orientation of the applied transverse load
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