8 research outputs found

    Urine Metabolomics Profiling of Lumbar Disc Herniation and its Traditional Chinese Medicine Subtypes in Patients Through Gas Chromatography Coupled With Mass Spectrometry

    Get PDF
    Lumbar disc herniation (LDH) possesses complex pathogenesis, which has not been well elucidated yet. To date, specific or early diagnosis of LDH remains unavailable, resulting in missed opportunity for effective treatment. According to Traditional Chinese medicine (TCM) theory, LDH can be divided into two subtypes (reality syndrome and deficiency syndrome). The purpose of this study was to analyze the metabolic disorders of LDH and its TCM subtypes and screen out potential biomarkers for LDH diagnosis. Gas chromatography coupled with mass spectrometry (GC-MS) was applied to test the urine samples from 66 participants (30 healthy volunteers, 18 LDH patients with deficiency syndrome and 18 patients with reality syndrome). PCA analysis showed a distinct separation tendency between the healthy subjects and LDH patients but no obvious separation between the different syndromes (reality syndrome and deficiency syndrome) of LDH patients. As a result, 23 metabolites were identified significantly altered in the LDH patients, as compared with the healthy subjects. The altered metabolites belong to amino acid metabolism, nucleic acid metabolism, carbohydrate metabolism, and vitamin metabolism, which are related to osteoporosis and inflammation. Our results indicate metabolic disorders of LDH and thereby propose a group of metabolic biomarkers for potential application in early diagnosis of LDH in clinic, which provide a reasonable explanation for the pathogenesis of LDH

    The Ginger-shaped Asteroid 4179 Toutatis: New Observations from a Successful Flyby of Chang'e-2

    Full text link
    On 13 December 2012, Chang'e-2 conducted a successful flyby of the near-Earth asteroid 4179 Toutatis at a closest distance of 770 ±\pm 120 meters from the asteroid's surface. The highest-resolution image, with a resolution of better than 3 meters, reveals new discoveries on the asteroid, e.g., a giant basin at the big end, a sharply perpendicular silhouette near the neck region, and direct evidence of boulders and regolith, which suggests that Toutatis may bear a rubble-pile structure. Toutatis' maximum physical length and width are (4.75 ×\times 1.95 km) ±\pm10%\%, respectively, and the direction of the +zz axis is estimated to be (250±\pm5^\circ, 63±\pm5^\circ) with respect to the J2000 ecliptic coordinate system. The bifurcated configuration is indicative of a contact binary origin for Toutatis, which is composed of two lobes (head and body). Chang'e-2 observations have significantly improved our understanding of the characteristics, formation, and evolution of asteroids in general.Comment: 21 pages, 3 figures, 1 tabl

    Mutual Aerodynamic Interference Mechanism Analysis of an “X” Configuration Quadcopter

    No full text
    This paper studies the quadcopter’s mutual interference phenomenon. The flow field of the quadcopter at different flight speeds is simulated by solving the three-dimensional unsteady Reynolds averaged Navier-Stokes equations with sliding mesh methods. “Virtual Modes” (VMs) are introduced to examine the mechanisms of aerodynamic interference among the quadcopter’s components (front rotors, rear rotors, and fuselage). By comparing the aerodynamic forces of different VMs, this work shows that mutual interference to the front rotors can be negligible, interference to the rear rotors is due to the wake of front rotors and fuselage, and mutual interference to fuselage is caused by front and rear rotors. Only the rear rotors’ thrust and pitch moment as well as the lift of the fuselage are significant. At the flight speed of 5–15 m/s, the mutual interference causes 11% loss of thrust and 35% loss of pitching moment to the rear rotors; In the cases of hovering and 25 m/s forward flight, the interference is negligible

    Space: Science & Technology—Promoting Academic Exchange and Exploring the Frontiers of Space

    No full text

    Rapid Fabrication of Porous Composite Hydrogels for Efficient Solar Vapor Generation

    No full text
    Solar vapor generation (SVG) has become a promising and sustainable technology for water purification and desalination. Recently, porous hydrogel-based solar evaporators that combine reduced water evaporation enthalpy and adequate water replenishment have demonstrated a highly effective SVG performance. However, it remains challenging to realize rapid and low-cost fabrication of porous hydrogel evaporators for practical applications. Herein, we report a facile and rapid method (photoinduced polymerization, c.a. 15 s) to fabricate porous composite hydrogels for effective solar seawater evaporation without time-consuming modification and post-treatment. The hydrogel evaporators show laminated composite structures that consist of carbon fiber felt for solar harvesting and an open microporous polyacrylamide-co-poly(N-isopropyl acrylamide) (PAM-co-PNIPAAm) hydrogel for water transport. After composition with photothermal carbon fiber felt (CFF), the CFF/PAM-co-PNIPAAm composite hydrogel evaporators exhibit rapid photothermal heating, in conjunction with the reduced water evaporation enthalpy and continuous water supply for solar evaporation, enabling an evaporation rate of 1.34 kg m–2 h–1 from 3.5 wt % NaCl solution under one sun irradiation, which approaches the theoretical evaporation rate limit of 2D evaporators (1.46 kg m–2 h–1). It is expected that the simple and fast fabrication method presented in this study, without the typical need for expensive raw materials and tedious procedures, will promote the application of hydrogel solar evaporators for water purification
    corecore