Deformed wing virus (DWV), a member of the genus iflavirus of the insect picorna-like viruses, is one of the most common honey bee viruses transmitted by the parasitic mite Varroa destructor during ...pupal stages, and is associated with wing deformities in adult honeybees. Although no data are available from Turkey up till now, DWV have been reported in many countries from all continents. In the present study, we tested the presence of DWV in Apis mellifera L and V. destructor from Ordu province of Turkey using one step reverse transcription-PCR (RT-PCR). We were able to demonstrate that all of the worker bees with deformed wings and the varroa mites but not healthy bees were infected with DWV. BLAST analysis of the sequences of PCR products showed 96-98% similarity to polyprotein gene of known DWV virus isolates.
We investigated the darkening of two high
OH
-
content quartz fibres irradiated with 24
GeV protons at the Cern PS facility IRRAD. The two tested fibres have a 0.6
mm quartz core diameter, one with ...hard plastic cladding (qp) and the other with quartz cladding (qq). These fibres were exposed at about 1.25
Grad in 3 weeks. The fibres became opaque below 380
nm and in the range 580–650
nm. The darkening under irradiation and damage recovery after irradiation as a function of dose and time are similar to what we observed with electrons. The typical attenuation at 455
nm are
1.44
±
0.22
and
2.20
±
0.15
dB
/
m
at 100
Mrad for qp and qq fibres, respectively. The maximum damage recovery is also observed near this wavelength.
Approximately 2000 PMTs will be used to detect the Cherenkov light generated in quartz fibers embedded in the CMS-HF Forward Calorimeter. The Hamamatsu R7525HA PMT was chosen for this purpose. We ...measured the transit time, transit time spread, pulse width, rise time, anode dark current, and relative gain for each tube in the test station at the University of Iowa. Life-time, gain versus high voltage, and single photoelectron spectrum measurements were also done on a small sample of PMTs. All the tubes were tested to verify that they conform to the HF requirements.
This report summarizes the radiation damage and the light transmission efficiency studies done on air core light guides with three different types of reflective material: two types of aluminized ...Mylar and a highly reflective plastic film from 3M called Radiant Mirror Film. The variations in light transmission efficiencies of these reflective materials have been studied with respect to the wavelengths of the incident light. The light transmission with one type of aluminized Mylar, which shows better reflectivity in UV range, deteriorated 14% after 10 Mrad of /spl gamma/-ray irradiation from a 9.5 kCurie /sup 137/Cs source. Light guides with the other type of aluminized Mylar and Radiant Mirror Film do not seem to be affected from radiation, and they show superior light transmission efficiency in the visible region.
Charged kaon mass measurement using the Cherenkov effect Graf, N.; Lebedev, A.; Abrams, R.J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2010, Letnik:
615, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The two most recent and precise measurements of the charged kaon mass use X-rays from kaonic atoms and report uncertainties of 14 and 22
ppm yet differ from each other by 122
ppm. We describe the ...possibility of an independent mass measurement using the measurement of Cherenkov light from a narrow-band beam of kaons, pions, and protons. This technique was demonstrated using data taken opportunistically by the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory which recorded beams of protons, kaons, and pions ranging in momentum from
+
37
to
+
63
GeV
/
c
. The measured value is
491.3
±
1.7
MeV
/
c
2
, which is within
1.4
σ
of the world average. An improvement of two orders of magnitude in precision would make this technique useful for resolving the ambiguity in the X-ray data and may be achievable in a dedicated experiment.
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