914 research outputs found
Examination of Acid-Fast Bacilli in Sputum Using Modified Light Microscope with Homemade Light Emitting Diode Additional Attachment
Typical clinical symptoms and chest X-ray is a marker of Tuberculosis (TB) sufferers. However, the diagnosis of TB in adults should be supported by microscopic examination. Currently, Bacilli microscopic examination of acid-fast bacilli (AFB) in sputum by Ziehl-Neelsen (ZN) coloring is the most widely used. However, for reasons of convenience, especially for laboratories with a considerable amount of smear samples, and due to higher sensitivity compared with ZN staining, the World Health Organization (WHO) has recommended the use of auramine-O-staining (fluorochrome staining), which is visualized by light emitting diode (LED) fluorescence microscopy. The aim of this study was to evaluate the performance of modified light microscope with homemade LED additional attachment for examination of AFB in sputum using auramine-O-staining method. We compared the sensitivity and specificity of 2 kinds of AFB in sputum methods: ZN and fluorochrome, using culture on Lowenstein-Jensen media as the gold standard. The results showed auramine-O-staining gives more proportion of positive findings (81%) compared to the ZN method (70%). These results demonstrated that the sensitivity of auramine-O-staining was higher than ZN, however it gives more potential false positive results than ZN. The sensitivity of auramine-O-staining in detecting AFB in sputum was 100% while the specificity was 88%
The Trialectics of Knowledge, Space and Identity in Ancient Civilizations and in the Study of Antiquity
Topoi research group B-4 Space â Identity â Locality focuses its research on
the interconnections between knowledge, space and identities. A multiplicity
of sources â texts, images, architecture and objects â are analyzed both in
their historical context and for their historiographic value. Following a
brief description of the projects, key concepts of knowledge, space and
identity are outlined as they relate to our specific research themes. We use
âtrialecticsâ to emphasize that knowledge, space and identity constitute and
influence each other. Concrete configurations of this constantly changing
interplay of factors are illustrated by two case studies â the ritual
compositions from Kizzuwatna (present southern Turkey) and the coin hoard of
Krepost (present Bulgaria)
A high-resolution bathymetry map for the Marguerite Bay and adjacent west Antarctic Peninsula shelf for the Southern Ocean GLOBEC Program
One objective of the U.S. Southern Ocean Global Ocean Ecosystems
Dynamics (SO GLOBEC) program is to gain a better understanding of the
sea floor bathymetry in the program study area. Much of Marguerite Bay
and the adjacent shelf west of the Antarctic Peninsula were poorly charted
when the SO GLOBEC program started in 2000. Before the first SO
GLOBEC cruise, an improved local area version (ETOPO8.2A) was created
from the Smith and Sandwell (1997) topo_8.2.img 2-minute digital gridded
bathymetry for the study area. The first SO GLOBEC mooring cruise on
the R/V Lawrence M. Gould (March 2001) showed that the 2-minute spatial
resolution of ETOPO8.2A did not resolve many of the canyons and abrupt
changes in topography that characterize Marguerite Bay and the inner- to
mid-shelf region. It also was not particularly accurate in the more uniform
terrain regions. We then decided to collect as much multibeam bathymetry
data as possible during the SO GLOBEC broad-scale survey cruises on the
R/VIB Nathaniel B. Palmer and combine these data with all other
available multibeam and trackline bathymetry data to construct a digital
bathymetry database and map for the study area. The resulting database
has high-resolution data over much of the shelf and parts of Marguerite
Bay gridded at 2 seconds in latitude and 6 seconds in longitude spacing
between 65° to 71° S and 65° to 78° W. This technical report describes the
steps taken to assemble and construct this database and how to access the
data via the Internet.Funding was provided by the Office of Naval Research under Contract No. N00014-99-1-0213
Receptor for advanced glycation endproducts (RAGE) deficiency protects against MPTP toxicity
Copyright © 2011 Elsevier Inc. All rights reserved.Peer reviewedPublisher PD
Competition of fusion and quasi-fission in the reactions leading to production of the superheavy elements
The mechanism of fusion hindrance, an effect observed in the reactions of
cold, warm and hot fusion leading to production of the superheavy elements, is
investigated. A systematics of transfermium production cross sections is used
to determine fusion probabilities. Mechanism of fusion hindrance is described
as a competition of fusion and quasi-fission. Available evaporation residue
cross sections in the superheavy region are reproduced satisfactorily. Analysis
of the measured capture cross sections is performed and a sudden disappearance
of the capture cross sections is observed at low fusion probabilities. A
dependence of the fusion hindrance on the asymmetry of the projectile-target
system is investigated using the available data. The most promising pathways
for further experiments are suggested.Comment: 8 pages, 7 figures, talk presented at 7th International
School-Seminar on Heavy-Ion Physics, May 27 - June 1, 2002, Dubna, Russi
Intense non-neutral beam propagation in a periodic solenoidal field using a macroscopic fluid model with zero thermal emittance
A macroscopic fluid model is developed to describe the nonlinear dynamics and collective processes in an intense high-current beam propagating in the z-direction through a periodic focusing solenoidal field B{sub z}(z + S) = B{sub z}(z), where S is the axial periodicity length. The analysis assumes that space-charge effects dominate the effects of thermal beam emittance, Kr{sub b}{sup 2} {much_gt} {epsilon}{sub th}{sup 2}, and is based on the macroscopic moment-Maxwell equations, truncated by neglecting the pressure tensor and higher-order moments. Assuming a thin beam with r{sub b} {much_lt} S, azimuthally symmetric beam equilibria with {partial_derivative}/{partial_derivative}t = 0 = {partial_derivative}/{partial_derivative}{theta} are investigated. To illustrate the considerable flexibility of the macroscopic formalism, assuming (nearly) uniform axial flow velocity V{sub b} over the beam cross section, beam equilibrium properties are calculated for two examples: (a) uniform radial density profile over the interval 0 {le} r < r{sub b}(z), and (b) an infinitesimally thin annular beam centered at r = r{sub b}(z). The analysis generally allows for the azimuthal flow velocity V{sub {theta}b}(r,z) to differ from the Larmor frequency, and the model is used to calculate the (leading-order) correction {delta}V{sub zb}(r,z) to the axial flow velocity for the step-function density profile in case (a) above
Short monolithic dual-wavelength single-longitudinal-mode DBR phosphate fiber laser
We propose and demonstrate a 5-cm-long monolithic dual-wavelength single-longitudinal mode distributed Bragg reflector (DBR) all-phosphate fiber laser. Strong UV-induced fiber Bragg gratings are directly written in highly Er/Yb codoped phosphate fiber. The separation between gratings is selected as 1 cm to only excite two longitudinal modes in the DBR cavity. By exploiting the spatial hole burning effect and the polarization hole burning effect, stable narrow-linewidth dual-wavelength lasing emission with 38 pm wavelength spacing and a total emitted power of 2.8 mW is obtained from this DBR fiber laser. A microwave signal at 4.58 GHz is generated by the heterodyne detection of the dual-wavelength laser
Photosensitivity and thermal stability of UV-induced fiber Bragg gratings in phosphate glass fibers
The photosensitivity of highly Er/Yb doped and undoped phosphate glass fibers is characterized under irradiation with intense pulsed 193 nm light from an ArF excimer laser through a phase mask. The ultraviolet photosensitivity of the active fibers is shown to be roughly half that of the passive fibers. We also demonstrate that the strong growth of the fiber Bragg grating reflectivity observed upon heating at temperatures between 100 - 250 degrees C is directly related to the UV irradiation time, but not to the size of the index modulation of the seed grating or even to the fiber type (Er/Yb doped or undoped). The conditions to reliably obtain final index modulations amplitudes between 5 and 10 x 10(-5) are given
Ru on Nâdoped Carbon for the Selective Hydrogenolysis of Sugars and Sugar Alcohols
Glycols are accessible via metalâcatalyzed hydrogenolysis of sugar alcohols such as xylitol obtained from hemicellulose. Ruâbased catalysts are highly active but also catalyze sideâreactions such as decarbonylation and deoxygenation. To achieve high selectivity, these reactions need to be suppressed. In our study, we introduce heteroatom doped carbon materials as catalyst supports providing high selectivity. Heteroatom doping with nitrogen and oxygen was achieved by treating activated carbon with HNOâ, NHâ and Hâ or carbonization of organic precursors. For all Nâdoped materials a high glycol selectivity of ⌠80 % for sorbitol and xylitol and 44 % for xylose and glucose was reached. XPS analysis confirms the presence of different nitrogen species at the carbon surface and varying ligand effects for oxygen and nitrogen. Oxygen has an electron withdrawing effect on ruthenium and leads to a decreased activity. Nitrogen has weaker electron withdrawing properties, resulting in an enhanced selectivity
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