36,205 research outputs found
Application of bag sampling technique for particle size distribution measurements
Bag sampling techniques can be used to temporarily store an aerosol and therefore provide sufficient time to utilize sensitive but slow instrumental techniques for recording detailed particle size distributions. Laboratory based assessment of the method were conducted to examine size dependant deposition loss coefficients for aerosols held in VelostatTM bags conforming to a horizontal cylindrical geometry. Deposition losses of NaCl particles in the range of 10 nm to 160 nm were analysed in relation to the bag size, storage time, and sampling flow rate. Results of this study suggest that the bag sampling method is most useful for moderately short sampling periods of about 5 minutes
An Application of Web 3.0: Positive WOM for Mobile Location-Based Apparel Shopping Services Usage
Web 3.0 is defined as the next paradigm shift of the Internet taking the best of web 2.0, including rich Internet applications and social media, and bringing them to mobile Internet devices and digital signage. Web 3.0 trends include a shift to outernet, location-based experiences, and the use of voice recognition in search applications (Buscemi & Marks, 2010). Mobile location-based services (LBS) offer shoppers reward opportunities when they physically visit stores or scan certain items
The Dynamical Behaviors in (2+1)-Dimensional Gross-Neveu Model with a Thirring Interaction
We analyze (2+1)-dimensional Gross-Neveu model with a Thirring interaction,
where a vector-vector type four-fermi interaction is on equal terms with a
scalar-scalar type one. The Dyson-Schwinger equation for fermion self-energy
function is constructed up to next-to-leading order in 1/N expansion. We
determine the critical surface which is the boundary between a broken phase and
an unbroken one in () space. It is observed that the
critical behavior is mainly controlled by Gross-Neveu coupling and
the region of the broken phase is separated into two parts by the line
. The mass function is strongly
dependent upon the flavor number N for , while weakly for
, the critical flavor number
increases as Thirring coupling decreases. By driving the CJT
effective potential, we show that the broken phase is energetically preferred
to the symmetric one. We discuss the gauge dependence of the mass function and
the ultra-violet property of the composite operators.Comment: 19 pages, LaTex, 6 ps figure files(uuencoded in seperate file
Chemical Topography of Efferent Projections from the Median Preoptic Nucleus to Pontine Monoaminergic Cell Groups in the Rat
This study examined efferent output from the median preoptic nucleus (MNPO) to pontine noradrenergic and serotonergic cell groups using an anterograde tracing technique (Phaseolus vulgaris leucoagglutinin, PHA-L) combined with glucose oxidase immunocytochemistry to serotonin (5-HT) or to dopamine-beta-hydroxylase (DBH). Injections of PHA-L into the ventral MNPO resulted in moderate axonal labeling within the region of the B7 and B8 serotonergic groups in the dorsal raphe. PHA-L labeled fibers and punctate processes were observed in close apposition to many of the 5-HT immunoreactive neurons in these regions. In contrast, sparse terminal labeling was found within the B5 group in the raphe pontis nucleus, and only trace fiber labeling observed in the B3 and B6 groups. Efferents from the MNPO also provided moderate innervation to the A6 and A7 noradrenergic groups. PHA-L labeled punctate processes were found most frequently in close apposition to DBH-immunoreactive neurons at mid- to caudal levels of the locus coeruleus. Some labeled axons were also present within the A7 and A5 groups. Additionally, a close apposition between labeled MNPO efferents and 5-HT fibers within the lateral parabrachial nucleus was observed. The results indicate the MNPO provides a topographic innervation of monoaminergic groups in the upper brainstem
X-Ray Microanalysis of Urinary Stones, a Comparison with Other Methods
A previous study of urinary stones by a combined electron microscopy demonstrated the potential of scanning electron microscopy and X- ray analysis as an analytic tool for urinary stones. Electron diffraction was chosen for the final confirmation of crystals in the study. Although electron diffraction is highly accurate for this purpose, it is desirable to establish the sensitivity of X-ray analysis for the identification of stone components relative to the more commonly used methods. Eighty six consecutive urinary stones were analyzed by X-ray analysis and the findings were compared with those of X-ray diffraction, infrared spectrometry and chemical analysis. The results indicate that X-ray analysis exceeds X-ray diffraction and infrared spectroscopy in its sensitivity for the identification of stone components several fold. This was largely due to the inability of the latter methods to detect apatite in more than half of the apatite containing stones. The findings in X-ray analysis had the best correlation with chemical analysis, which was applied mainly to the detection of apatite. X-ray analysis is particularly suited for the detection of rare and minor inorganic components of urinary stones such as silica and gypsum, and is obviously one of the most powerful tools for the analysis of urinary stones. Further application of X-ray analysis to urinary stone is likely to discern rare inorganic components of urinary stones overlooked by other methods
A planetary companion around the K giant eps Corona Borealis
Aims. Our aim is to search for and study the origin of the low-amplitude and
long-periodic radial velocity (RV) variations in K giants. Methods. We present
high-resolution RV measurements of K2 giant epsilon CrB from February 2005 to
January 2012 using the fiber-fed Bohyunsan Observatory Echelle Spectrograph
(BOES) at the Bohyunsan Optical Astronomy Observatory (BOAO). Results. We find
that the RV measurements for epsilon CrB exhibit a periodic variation of 417.9
+/- 0.5 days with a semi-amplitude of 129.4 +/- 2.0 m/s. There is no
correlation between RV measurements and chromospheric activity in the Ca II H
region, the Hipparcos photometry, or bisector velocity span. Conclusions.
Keplerian motion is the most likely explanation, with the RV variations arising
from an orbital motion. Assuming a possible stellar mass of 1.7 +/- 0.1 M_Sun
for epsilon CrB, we obtain a minimum mass for the planetary companion of 6.7
+/- 0.3 M_Jup with an orbital semi-major axis of 1.3 AU and eccentricity of
0.11. We also discuss the implications of our observations for stellar
metallicity versus planet occurrence rate and stellar mass versus planetary
mass relations.Comment: 5 pages, 7 figures, 3 tables, accepted for publisation in Astronomy &
Astrophysic
Latino Retail Entrepreneurship in Minnesota: Implications for Extension Educators
Minnesota has become a “new destination” state for Latino migrants in the United States. What has made Latinos in Minnesota successful? In a narrower sense, what has provided them with a route out of poverty and an alternative to unemployment or discrimination in the labor market? Our purpose was to (a) compile characteristics associated with the Latino community and successful Latino-owned retail businesses in Minnesota, (b) identify unique problems encountered by Latino retail entrepreneurs, and (c) develop recommendations to overcome obstacles encountered. To meet our objectives, we employed two methods: a Delphi study with Latino community leaders and a case study with Latino retail entrepreneurs. Implications for Extension educators are discussed
Phenomenological local potentials for \pi^- + ^{12}C scattering from 120 to 766 MeV
Pion-nucleus scattering cross sections are calculated by solving a
Schr\"{o}dinger equation reduced from the Klein-Gordon equation. Local
potentials are assumed, and phenomenological potential parameters are searched
energy-dependently for C system so as to reproduce not only
elastic differential cross sections but also total elastic, reaction and total
cross sections at 13 pion incident energies from 120 to 766 MeV. The real and
imaginary parts of the local potentials thus obtained are shown to satisfy the
dispersion relation. The imaginary part of the potentials as a function of the
pion energy is found to peak near the (1232)-resonance energy. The
strong absorption radius of the pion projectile with incident energies near the
-resonance region is found to be about fm, which is
consistent with previous studies of the region where the decay of the
's takes place in nuclei. The phenomenological local potentials are
then compared with the local potentials exactly phase-shift equivalent to
Kisslinger potentials for pion energies near the -resonance
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