1,281 research outputs found

    A Patterned Single Layer Graphene Resistance Temperature Sensor

    Get PDF
    Micro-fabricated single-layer graphenes (SLGs) on a silicon dioxide (SiO2)/Si substrate, a silicon nitride (SiN) membrane, and a suspended architecture are presented for their use as temperature sensors. These graphene temperature sensors act as resistance temperature detectors, showing a quadratic dependence of resistance on the temperature in a range between 283โ€‰K and 303โ€‰K. The observed resistance change of the graphene temperature sensors are explained by the temperature dependent electron mobility relationship (~Tโˆ’4) and electron-phonon scattering. By analyzing the transient response of the SLG temperature sensors on different substrates, it is found that the graphene sensor on the SiN membrane shows the highest sensitivity due to low thermal mass, while the sensor on SiO2/Si reveals the lowest one. Also, the graphene on the SiN membrane reveals not only the fastest response, but also better mechanical stability compared to the suspended graphene sensor. Therefore, the presented results show that the temperature sensors based on SLG with an extremely low thermal mass can be used in various applications requiring high sensitivity and fast operation

    Potassium-doped BaFe2As2 superconducting thin films with a transition temperature of 40 K

    Full text link
    We report the growth of potassium-doped BaFe2As2 thin films, where the major charge carriers are holes, on Al2O3 (0001) and LaAlO3 (001) substrates by using an ex-situ pulsed laser deposition technique. The measured Tc's are 40 and 39 K for the films grown on Al2O3 and LaAlO3, respectively and diamagnetism indicates that the films have good bulk superconducting properties below 36 and 30 K, respectively. The X-ray diffraction patterns for both films indicated a preferred c-axis orientation, regardless of the substrate structures of LaAlO3 and Al2O3. The upper critical field at zero temperature was estimated to be about 155 T.Comment: 6 pages including 3 figure

    Robotic pylorus preserving pancreaticoduodenectomy with mini-laparotomy reconstruction in patient with ampullary adenoma

    Get PDF
    Robotic surgical system provides many unique advantages which might compensate the limitations of usual laparoscopic surgery. By using robotic surgical system, we performed robot-assisted laparoscopic pancreaticoduodenectomy (PD). A Sixty-two year old female patient with an ampullary mass underwent robot assisted PD due to imcomplete treatment of endoscopic ampullectomy. The removal of specimen and reconstruction were performed through small upper midline skin incision. Robot working time was about 8 hours, and blood loss was about 800 ml without blood transfusion. She returned to an oral diet on postoperative day 3. Grade B pancreatic leak was noted during the postoperative period, but was successfully managed by conservative management alone. We successfully performed da Vinci-assisted laparoscopic PD, and robot surgical system provided three-dimensional stable visualization and wrist-like motion of instrument facilitated complex operative procedures. More experiences are necessary to address real role of robot in far advanced laparoscopic pancreatic surgery

    Purification and Properties of Arginase from Soybean, Glycine max

    Full text link

    Concomitant Laparoendoscopic Single-Site Surgery for Vesicolithotomy and Finger-Assisted Single-Port Transvesical Enucleation of the Prostate

    Get PDF
    Transurethral resection of the prostate is the most common surgery for benign prostatic hyperplasia. However, it doesn't work best for men with very large prostate and bladder stones. Herein we report our initial experience with concomitant laparoendoscopic single-site surgery and finger-assisted single-port transvesical enucleation of the prostate for the treatment of the condition

    Tracing the historical origin of Joseon mummies considering the structural similarities between the burial systems of Korean and Chinese dynasties

    Get PDF
    Joseon mummies have proved to be excellent subjects for scientific research on the health and disease statuses of pre-modern Korean peoples. Despite its academic significance, the origins of the Hoegwakmyo tomb in which the Joseon mummy was discovered have not yet been entirely revealed. Meanwhile, over the past several decades, there have been some reports on mummies and cultural artifacts preserved very well in the tombs of several Chinese dynasties (especially Song, Yuan, Ming and Qing). Although the Chinese tombs were very diverse in structure, we note that some graves among them were structurally very similar to Joseon Hoegwakmyo tombs. Before the Hoegwakmyo tomb in Korea, there were already similar tombs in China, inside which dead persons were mummified like the Joseon mummies. Considering that the Hoegwakmyo tomb of the Joseon Dynasty was established by the influence of the Confucian ideology, the Korean and Chinese mummies might share common cultural origins in history

    In-situ fabrication of cobalt-doped SrFe2As2 thin films by using pulsed laser deposition with excimer laser

    Full text link
    The remarkably high superconducting transition temperature and upper critical field of iron(Fe)-based layered superconductors, despite ferromagnetic material base, open the prospect for superconducting electronics. However, success in superconducting electronics has been limited because of difficulties in fabricating high-quality thin films. We report the growth of high-quality c-axis-oriented cobalt(Co)-doped SrFe2As2 thin films with bulk superconductivity by using an in-situ pulsed laser deposition technique with a 248-nm-wavelength KrF excimer laser and an arsenic(As)-rich phase target. The temperature and field dependences of the magnetization showing strong diamagnetism and transport critical current density with superior Jc-H performance are reported. These results provide necessary information for practical applications of Fe-based superconductors.Comment: 8 pages, 3figures. to be published at Appl. Phys. Let

    DHP-Derivative and Low Oxygen Tension Effectively Induces Human Adipose Stromal Cell Reprogramming

    Get PDF
    BACKGROUND AND METHODS: In this study, we utilized a combination of low oxygen tension and a novel anti-oxidant, 4-(3,4-dihydroxy-phenyl)-derivative (DHP-d) to directly induce adipose tissue stromal cells (ATSC) to de-differentiate into more primitive stem cells. De-differentiated ATSCs was overexpress stemness genes, Rex-1, Oct-4, Sox-2, and Nanog. Additionally, demethylation of the regulatory regions of Rex-1, stemnesses, and HIF1alpha and scavenging of reactive oxygen species were finally resulted in an improved stem cell behavior of de-differentiate ATSC (de-ATSC). Proliferation activity of ATSCs after dedifferentiation was induced by REX1, Oct4, and JAK/STAT3 directly or indirectly. De-ATSCs showed increased migration activity that mediated by P38/JUNK and ERK phosphorylation. Moreover, regenerative efficacy of de-ATSC engrafted spinal cord-injured rats and chemical-induced diabetes animals were significantly restored their functions. CONCLUSIONS/SIGNIFICANCE: Our stem cell remodeling system may provide a good model which would provide insight into the molecular mechanisms underlying ATSC proliferation and transdifferentiation. Also, these multipotent stem cells can be harvested may provide us with a valuable reservoir of primitive and autologous stem cells for use in a broad spectrum of regenerative cell-based disease therapy
    • โ€ฆ
    corecore