2,374 research outputs found
Proizvodnja antikomplementnih egzopolisaharida submerznim uzgojem gljive Flammulina velutipes
Seven species of basidiomycetes have been investigated for anti-complementary activity in hot water extracts and ethanol soluble fractions. Since Flammulina velutipes had the most potent activity, culture conditions for its mycelial growth were optimized to increase the production efficiency of anti-complementary exopolysaccharides. The optimal medium composition was (in g/L): galactose 15, sodium nitrate 5, glutamic acid 3, KH2PO4 2.5 and MgSO4·7H2O 0.6. Optimal production of anti-complementary activity was achieved at pH=3.5–5.5 and 25 °C. With these optimal medium and culture conditions, mycelial dry mass was maximized at 3.17 mg/mL after 6 days of cultivation in a 5-liter stirred-tank bioreactor, without pH control. The anti-complementary activity of exopolysaccharides increased sharply after 4 days of cultivation, and showed a high level at 5–6 days of cultivation. A periodate-labile carbohydrate moiety played a leading role in the anti-complementary activity exhibited by exopolysaccharide produced from F. velutipes. Results of tests on the anti-complementary activity in the absence of Ca²+ and immunoelectrophoresis indicated that the mode of complement activation by exopolysaccharide from F. velutipes is via both the classical and alternative pathways and that the activation degree is almost the same in each pathway.Istražena je antikomplementna aktivnost spojeva ekstrahiranih vrućom vodom i etanolom iz sedam vrsta gljiva stapčara. Optimirani su uvjeti uzgoja micelija gljive s najvećom aktivnosti, Flammulina velutipes, radi povećanja proizvodnje antikomplementnih egzopolisaharida. Optimalni sastav podloge bio je (u g/L): galaktoza 15, natrijev nitrat 5, glutamična kiselina 3, KH2PO4 2,5 i MgSO4·7H2O 0,6. Optimalna proizvodnja postignuta je pri pH=3,5-5,5 i 25 ºC. Pri tim uvjetima proizvedena je maksimalna količina suhe tvari od 3,17 mg/L nakon 6 dana uzgoja u bioreaktoru s miješalicom zapremnine 5 L, bez kontrole pH-vrijednosti. Antikomplementna aktivnost egzopolisaharida naglo se povećala nakon 4 dana, te je bila visoka nakon 5-6 dana uzgoja. Šećerni je ostatak, podložan djelovanju perjodata, glavni razlog antikomplementne aktivnosti egzopolisaharida gljive F. velutipes. Rezultati testiranja takve aktivnosti u odsutnosti Ca²+ iona i imunoelektroforeza upućuju na to da se komplementi egzopolisaharida iz F. velutipes aktiviraju klasičnim i alternativnim putem te da je stupanj aktivacije skoro jednak za oba puta
Potassium-doped BaFe2As2 superconducting thin films with a transition temperature of 40 K
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
Optical spectroscopic investigation on the coupling of electronic and magnetic structure in multiferroic hexagonal RMnO3 (R = Gd, Tb, Dy, and Ho) thin films
We investigated the effects of temperature and magnetic field on the
electronic structure of hexagonal RMnO3 (R = Gd, Tb, Dy, and Ho) thin films
using optical spectroscopy. As the magnetic ordering of the system was
disturbed, a systematic change in the electronic structure was commonly
identified in this series. The optical absorption peak near 1.7 eV showed an
unexpectedly large shift of more than 150 meV from 300 K to 15 K, accompanied
by an anomaly of the shift at the Neel temperature. The magnetic field
dependent measurement clearly revealed a sizable shift of the corresponding
peak when a high magnetic field was applied. Our findings indicated strong
coupling between the magnetic ordering and the electronic structure in the
multiferroic hexagonal RMnO3 compounds.Comment: 16 pages including 4 figure
In-situ fabrication of cobalt-doped SrFe2As2 thin films by using pulsed laser deposition with excimer laser
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
A STUDY ON THE LONG-TERM MONITORING OF SPORTS ACTIVITIES
INTRODUCTION: Lots of studies to analyze and classify human movement patterns using various sensors have been carried out (Mathie, 2004; Allen, 2006) because accurate information of body activity is required to provide promotion of health and health plan. Thus this study was conducted to study the classification and monitoring of various sports activities in real-time environment using single waist mounted tri-axial accelerometer
- …