3,067 research outputs found
Environmental tobacco smoke and children's health
Passive exposure to tobacco smoke significantly contributes to morbidity and mortality in children. Children, in particular, seem to be the most susceptible population to the harmful effects of environmental tobacco smoke (ETS). Paternal smoking inside the home leads to significant maternal and fetal exposure to ETS and may subsequently affect fetal health. ETS has been associated with adverse effects on pediatric health, including preterm birth, intrauterine growth retardation, perinatal mortality, respiratory illness, neurobehavioral problems, and decreased performance in school. A valid estimation of the risks associated with tobacco exposure depends on accurate measurement. Nicotine and its major metabolite, cotinine, are commonly used as smoking biomarkers, and their levels can be determined in various biological specimens such as blood, saliva, and urine. Recently, hair analysis was found to be a convenient, noninvasive technique for detecting the presence of nicotine exposure. Because nicotine/cotinine accumulates in hair during hair growth, it is a unique measure of long-term, cumulative exposure to tobacco smoke. Although smoking ban policies result in considerable reductions in ETS exposure, children are still exposed significantly to tobacco smoke not only in their homes but also in schools, restaurants, child-care settings, cars, buses, and other public places. Therefore, more effective strategies and public policies to protect preschool children from ETS should be consolidated
Properties of Magnesia Composites According to Replacement Ratio of Perlite
Recently, passive and zero-energy construction has increased in Korea due to the government`s continuous application of budget-conscious policies for establishments. Accordingly, construction materials are being advanced, and the required performance standards for insulation materials are increasing. However, problems such as fire vulnerability and degradation of physical properties for organic and inorganic insulation materials are shown, so it is necessary to solve this problem. The objective of this research is to examine the properties of the composites by analyzing the flexural breaking load, impact resistance, density, VOCs concentration reduction rate, and fine dust concentration reduction rate of the composites manufactured based on the perlite substitution rate of the magnesia composites. The flexural breaking load test of the composites was assessed according to ‘KS F 3504’, a gypsum board standard and the impact resistance was assessed according to ‘KS F 4715’. The performance evaluation of adsorption performance of air pollutants of the VOCs and fine dust in the context of the small chamber technique suggested by Hanbat University. The results of this study are as follows: The flexural breaking load according to the perlite replacement rate tended to decrease as the perlite replacement rate increased. It is determined that the flexural breaking load is reduced by generating a large amount of pores inside due to the perlite porous structure characteristics. In the case of impact resistance, the impact resistance tended to increase as the perlite displacement rate increased. It is determined that the volume of the binder in the board is reduced, and pores inside the board are generated due to perlite, which is a porous material, thereby reducing the overall bonding force of the board. In the case of VOCs and fine dust concentrations, the VOCs and fine dust concentration reduction rates tended to increase as the perlite replacement rate increased. In the case of the perlite displace rate of 30%, the VOCs concentration decreased by 82.6%, and the fine dust concentration decreased by 87.9%. It has been established that the porous properties of perlite used to create a huge number of pores in the hardened body cause the concentration to be lowered physically through adsorption. This study\u27s findings are thought to be fundamental information for securing the engineering properties and air pollution absorption of magnesia composites blended with perlite
The Globular Cluster System of M60 (NGC 4649). I. CFHT MOS Spectroscopy and Database
We present the measurement of radial velocities for globular clusters in M60,
giant elliptical galaxy in the Virgo cluster. Target globular cluster
candidates were selected using the Washington photometry based on the deep
16\arcmin \times 16\arcmin images taken at the KPNO 4m and using the
photometry derived from the HST/WFPC2 archive images. The spectra of the target
objects were obtained using the Multi-Object Spectrograph (MOS) at the
Canada-France-Hawaii Telescope (CFHT). We have measured the radial velocity for
111 objects in the field of M60: 93 globular clusters (72 blue globular
clusters with and 21 red globular clusters with
), 11 foreground stars, 6 small galaxies, and the nucleus of
M60. The measured velocities of the 93 globular clusters range from
km s to km s, with a mean value of
km s, which is in good agreement with the velocity of the nucleus of M60
( km s). Combining our results with data in the
literature, we present a master catalog of radial velocities for 121 globular
clusters in M60. The velocity dispersion of the globular clusters in the master
catalog is found to be km s for the entire sample,
km s for 83 blue globular clusters, and
km s for 38 red globular clusters.Comment: 29 pages, 8 figures. To appear in Ap
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THE DIFFERENCE OF RESIDENT AND NON-RESIDENT CUSTOMER BASED ON SERVICE QUALITY IN THE RESTAURANT BUSINESS USING CART METHODOLOGY
The food industry contributes to a nation’s economic development in many respects. According to the National Restaurant Association in 2009, there are 945,000 restaurants and sales in the restaurant industry are $566 billion a year, which make up about 13million people or 9% of the U.S. workforce food industry. Both the sales and the number of workforce engaged in the food industry have increased steadily since 1970. In other words, as the United States is experiencing remarkable growth in the restaurant business, there is a great deal of competition for surviving in competitive industry
Hubble Space Telescope Pixel Analysis of the Interacting Face-on Spiral Galaxy NGC 5194 (M51A)
A pixel analysis is carried out on the interacting face-on spiral galaxy NGC
5194 (M51A), using the HST/ACS images in the F435W, F555W and F814W (BVI)
bands. After 4x4 binning of the HST/ACS images to secure a sufficient
signal-to-noise ratio for each pixel, we derive several quantities describing
the pixel color-magnitude diagram (pCMD) of NGC 5194: blue/red color cut, red
pixel sequence parameters, blue pixel sequence parameters and blue-to-red pixel
ratio. The red sequence pixels are mostly older than 1 Gyr, while the blue
sequence pixels are mostly younger than 1 Gyr, in their luminosity-weighted
mean stellar ages. The color variation in the red pixel sequence from V = 20
mag arcsec^(-2) to V = 17 mag arcsec^(-2) corresponds to a metallicity
variation of \Delta[Fe/H] ~ 2 or an optical depth variation of \Delta\tau_V ~ 4
by dust, but the actual sequence is thought to originate from the combination
of those two effects. At V < 20 mag arcsec^(-2), the color variation in the
blue pixel sequence corresponds to an age variation from 5 Myr to 300 Myr under
the assumption of solar metallicity and \tau_V = 1. To investigate the spatial
distributions of stellar populations, we divide pixel stellar populations using
the pixel color-color diagram and population synthesis models. As a result, we
find that the pixel population distributions across the spiral arms agree with
a compressing process by spiral density waves: dense dust \rightarrow
newly-formed stars. The tidal interaction between NGC 5194 and NGC 5195 appears
to enhance the star formation at the tidal bridge connecting the two galaxies.
We find that the pixels corresponding to the central active galactic nucleus
(AGN) area of NGC 5194 show a tight sequence at the bright-end of the pCMD,
which are in the region of R ~ 100 pc and may be a photometric indicator of AGN
properties.Comment: 27 pages, 20 figures, accepted for publication in Ap
The Interaction of Phospholipase C-{beta}3 with Shank2 Regulates mGluR-mediated Calcium Signal
Phospholipase C-{beta} isozymes that are activated by G protein-coupled receptors (GPCR) and heterotrimeric G proteins carry a PSD-95/Dlg/ZO-1 (PDZ) domain binding motif at their C terminus. Through interactions with PDZ domains, this motif may endow the PLC-{beta} isozyme with specific roles in GPCR signaling events that occur in compartmentalized regions of the plasma membrane. In this study, we identified the interaction of PLC-{beta}3 with Shank2, a PDZ domain-containing multimodular scaffold in the postsynaptic density (PSD). The C terminus of PLC-{beta}3, but not other PLC-{beta} isotypes, specifically interacts with the PDZ domain of Shank2. Homer 1b, a Shank-interacting protein that is linked to group I metabotropic glutamate receptors and IP3 receptors, forms a multiple complex with Shank2 and PLC-{beta}3. Importantly, microinjection of a synthetic peptide specifically mimicking the C terminus of PLC-{beta}3 markedly reduces the mGluR-mediated intracellular calcium response. These results demonstrate that Shank2 brings PLC-{beta}3 closer to Homer 1b and constitutes an efficient mGluR-coupled signaling pathway in the PSD region of neuronal synapses
To the Edge of M87 and Beyond: Spectroscopy of Intracluster Globular Clusters and Ultra Compact Dwarfs in the Virgo Cluster
We present the results from a wide-field spectroscopic survey of globular
clusters (GCs) in the Virgo Cluster. We obtain spectra for 201 GCs and 55
ultracompact dwarfs (UCDs) using the Hectospec on the Multiple Mirror
Telescope, and derive their radial velocities. We identify 46 genuine
intracluster GCs (IGCs), not associated with any Virgo galaxies, using the 3D
GMM test on the spatial and radial velocity distribution.They are located at
the projected distance 200 kpc R 500 kpc from the center
of M87. The radial velocity distribution of these IGCs shows two peaks, one at
= 1023 km s associated with the Virgo main body, and another
at = 36 km s associated with the infalling structure. The
velocity dispersion of the IGCs in the Virgo main body is 314 km s, which is smoothly connected to the velocity dispersion
profile of M87 GCs, but much lower than that of dwarf galaxies in the same
survey field, 608 km s. The UCDs are more
centrally concentrated on massive galaxies, M87, M86, and M84. The radial
velocity dispersion of the UCD system is much smaller than that of dwarf
galaxies. Our results confirm the large-scale distribution of Virgo IGCs
indicated by previous photometric surveys. The color distribution of the
confirmed IGCs shows a bimodality similar to that of M87 GCs. This indicates
that most IGCs are stripped off from dwarf galaxies and some from massive
galaxies in the Virgo.Comment: 19 pages, 20 figures, 8 tables, accepted for publication in Ap
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