Research on Aircraft Cable Defects Locating Method Based on Time-Frequency Domain Reflection

AbstractThis paper presents an aircraft cable fault detection and location method based on TFDR in order to detect the intermittent faults effectively and to cope with the serial and after-connector faults being difficult to be detected in time domain reflection. In this method, the correlation function of reflected and reference signal is utilized to detect and locate the aircraft fault according to the characteristics of reflected and reference signal in time-frequency domain, so the hit rate of detecting and locating intermittent faults can be improved effectively. In the work process, the reflected signal is interfered by the noise and false alarm takes place frequently, so the threshold de-noising method based on wavelet decomposition is utilized to decrease the noise interference and reduce the fault alarm rate. Then the time-frequency cross correlation function of the reference signal and the reflected signal based on Wigner-Ville distribution is computed in order to locate the fault position. At last, LabVIEW is applied to implement operation and control interface, the main function of which is to link and control MATLAB and LABSQL. Utilizing the strong calculating capability and the abundant function library of MATLAB, the signal processing turn to be easily realized, moreover LabVIEW help the system to be more reliable and updated easily

Clinical Observation of Erlotinib in the Treatment of Advanced Non-small Cell Lung Cancer: A Report of 92 Eases

Background and objective Erlotinib, a selective inhibitor of epidermal growth factor receptor tyrosine kinase, has been approved effective in local advanced or metastatic non-small cell lung cancer (NSCLC). The aim of this study was to evaluate the efficacy and safety of erlotinib for the treatment of advanced NSCLC. Methods Ninety-two patients with advanced NSCLC who had failed or not tolerated or refused chemotherapy received 150 mg oral doses of erlotinib once daily until the disease progression or intolerable toxicity. Results Among the 92 NSCLC patients, 2 patient got complete response (2.2%), 22 partial response (23.9%), 48 stable disease (52.2%) and 20 progressive disease (21.7%). The overall response rate and the disease controlled rate of erlotinib was 26.1% (24/92) and 78.3% (72/92), respectively. The response rate of erlotinib were significantly higher in rash and ECOG 0-1 than no rash and ECOG ≥ 2. The disease controlled rate of erlotinib was significantly higher in female and non-smokers than male and smokers (P < 0.05). The response rate of erlotinib did not show significant differences within pathological type or previous treatment. The most common side effects were rash and diarrhea with 84.8% and 31.5%, respectively, but usually were mild. Conclusion Erlotinib is effective and safe in the treatment of advanced NSCLC patients

Self-Lubricating Polytetrafluoroethylene/Polyimide Blends Reinforced with Zinc Oxide Nanoparticles

ZnO nanoparticle reinforced polytetrafluoroethylene/polyimide (PTFE/PI) nanocomposites were prepared and their corresponding tribological and mechanical properties were studied in this work. The influences of ZnO loading, sliding load, and velocity on the tribological properties of ZnO/PTFE/PI nanocomposites were systematically investigated. Results reveal that nanocomposites reinforced with 3 wt% ZnO exhibit the optimal tribological and mechanical properties. Specifically, the wear loss decreased by 20% after incorporating 3 wt% ZnO compared to unfilled PTFE/PI. Meanwhile, the impact strength, tensile strength, and elongation-at-break of 3 wt% ZnO/PTFE/PI nanocomposite are enhanced by 85, 5, and 10% compared to pure PTFE/PI blend. Microstructure investigation reveals that ZnO nanoparticles facilitate the formation of continuous, uniform, and smooth transfer film and thus reduce the adhesive wear of PTFE/PI

Assembly of a high-dielectric constant thin TiOX layer directly on H-terminated semiconductor diamond

A high-dielectric constant (high-k) TiOx thin layer was fabricated on hydrogen-terminated diamond (H-diamond) surface by low temperature oxidation of a thin titanium layer in ambient air. The metallic titanium layer was deposited by sputter deposition. The dielectric constant of the resultant TiOx was calculated to be around 12. The capacitance density of the metal-oxide-semiconductor (MOS) based on the TiOx/H-diamond was as high as 0.75 µF/cm2 contributed from the high-k value and the very thin thickness of the TiOx layer. The leakage current was lower than 10-13 A at reverse biases and 10-7A at the forward bias of -2 V. The MOS field-effect transistor based on the high-k TiOx/H-diamond was demonstrated. The utilization of the high-k TiOx with a very thin thickness brought forward the features of an ideally low subthreshold swing slope of 65 mV per decade and improved drain current at low gate voltages. The advantages of the utilization high-k dielectric for diamond MOSFETs are anticipated

A Mechanistic Analysis of Phase Evolution and Hydrogen Storage Behavior in Nanocrystalline Mg(BH4)2 within Reduced Graphene Oxide.

Magnesium borohydride (Mg(BH4)2, abbreviated here MBH) has received tremendous attention as a promising onboard hydrogen storage medium due to its excellent gravimetric and volumetric hydrogen storage capacities. While the polymorphs of MBH-alpha (α), beta (β), and gamma (γ)-have distinct properties, their synthetic homogeneity can be difficult to control, mainly due to their structural complexity and similar thermodynamic properties. Here, we describe an effective approach for obtaining pure polymorphic phases of MBH nanomaterials within a reduced graphene oxide support (abbreviated MBHg) under mild conditions (60-190 °C under mild vacuum, 2 Torr), starting from two distinct samples initially dried under Ar and vacuum. Specifically, we selectively synthesize the thermodynamically stable α phase and metastable β phase from the γ-phase within the temperature range of 150-180 °C. The relevant underlying phase evolution mechanism is elucidated by theoretical thermodynamics and kinetic nucleation modeling. The resulting MBHg composites exhibit structural stability, resistance to oxidation, and partially reversible formation of diverse [BH4]- species during de- and rehydrogenation processes, rendering them intriguing candidates for further optimization toward hydrogen storage applications

Author Correction:3D-printed liquid metal polymer composites as NIR-responsive 4D printing soft robot

Correction to: Nature Communications https://doi.org/10.1038/s41467-023-43667-4, published online 28 November 2023

Thoracic endovascular aortic repair under venoarterial extracorporeal membrane oxygenation for acute aortic dissection patients: a case report

BackgroundOpen repair and replacement of the diseased aorta is still the standard treatment for type A aortic dissection (TAAD) in most patients. In endovascular treatment alone, ensuring adequate blood supply to the brain while covering the dissection with a stent is difficult.Case presentationThis study includes a 71-year-old male patient with type A aortic dissection presented at a recent follow-up examination after having undergone thoracic endovascular aortic repair (TEVAR) plus left subclavian artery chimney stent reconstruction for descending aortic dissection 5 years ago. Preoperative computed tomographic angiography, computed tomographic perfusion, and transcranial Doppler showed an intact cerebral arterial ring and good collateral circulation. We successfully performed an endovascular repair of the thoracic aorta with venoarterial extracorporeal membrane oxygenation (V-A ECMO) to protect the craniocerebral blood supply, greatly increase the safety of the operation, and ensure a good prognosis.ConclusionTEVAR under V-A ECMO protection is beneficial for patients with TAAD because of its minimal trauma, rapid recovery, few complications, and low mortality

Psoralen Induces Developmental Toxicity in Zebrafish Embryos/Larvae Through Oxidative Stress, Apoptosis, and Energy Metabolism Disorder

Psoralen toxicity is an issue of wide concern. However, an assay for psoralen-induced developmental toxicity has not been reported to date. Moreover, the underlying mechanism of psoralen-induced developmental toxicity is unclear. Therefore, this study attempted to develop a psoralen-induced developmental toxicity assay in zebrafish embryos/larvae. Psoralen treatment caused a decrease in the hatching rate and body length and a significant increase in the malformation rate of zebrafish. Yolk retention, pericardial edema, swim-bladder deficiency, and curved body shape were also observed after psoralen treatment. Yolk retention might have been caused by an abnormality in lipid metabolism. Further experiments indicated that psoralen exerted toxic effects on the developing heart, liver, phagocytes, and nervous system. Increased generation of reactive oxygen species, inhibition of total superoxide dismutase activity, and increased malondialdehyde concentrations indicated inhibition of antioxidant capacity and the presence of oxidative stress. A greater number of apoptotic cells were observed after psoralen exposure, relative to the control. Furthermore, the results of gene-expression analysis showed that psoralen induced developmental toxicity by means of oxidative stress, apoptosis, and energy metabolism abnormalities. These findings will be helpful in understanding psoralen-induced toxicity