Deep u*- and g-band Imaging of the Spitzer Space Telescope First Look Survey Field : Observations and Source Catalogs

We present deep u*-, and g-band images taken with the MegaCam on the 3.6 m Canada-France-Hawaii Telescope (CFHT) to support the extragalactic component of the Spitzer First Look Survey (hereafter, FLS). In this paper we outline the observations, present source catalogs and characterize the completeness, reliability, astrometric accuracy and number counts of this dataset. In the central 1 deg2 region of the FLS, we reach depths of g~26.5 mag, and u*~26.2 mag (AB magnitude, 5$\sigma$ detection over a 3" aperture) with ~4 hours of exposure time for each filter. For the entire FLS region (~5 deg2 coverage), we obtained u*-band images to the shallower depth of u*=25.0--25.4 mag (5$\sigma$, 3" aperture). The average seeing of the observations is 0.85" for the central field, and ~1.00" for the other fields. Astrometric calibration of the fields yields an absolute astrometric accuracy of 0.15" when matched with the SDSS point sources between 18<g<22. Source catalogs have been created using SExtractor. The catalogs are 50% complete and greater than 99.3% reliable down to g~26.5 mag and u*~26.2 mag for the central 1 deg2 field. In the shallower u*-band images, the catalogs are 50% complete and 98.2% reliable down to 24.8--25.4 mag. These images and source catalogs will serve as a useful resource for studying the galaxy evolution using the FLS data.Comment: 15 pages, 16 figure

Growth study on chrysene degraders isolated from polycyclic aromatic hydrocarbon polluted soils in Nigeria

Acinetobacter anitratus, Alcaligenes faecalis, Acinetobacter mallei and Micrococcus varians were isolated from polycyclic aromatic hydrocarbon polluted soils by enrichment culture using chrysene assole carbon and energy source. Physiochemical evaluation revealed that these isolates grew well at a temperature range of 20 - 40°C, pH 6.0-8.0 but less tolerable to various salt concentrations except Micrococcus varians which grew at 1.0 to 7.5% NaCl. These organisms utilized chrysene, anthracene, naphthalene, crude oil, kerosene, diesel and engine oil as sole carbon source. None could utilize benzene, hexane, xylene, phenol and toluene as carbon sources. Growth study of the isolates on 0.1%(w/v) chrysene resulted in highest cell density of 8.8x107, 7.9x107, 6.3x106, 6.3x106 cfu/ml for A. anitratus, Alc. faecalis, A. mallei and M. varians, respectively. There was statistical significant difference (P< 0.05) in the growth of these organisms on chrysene as sole carbon and energy source when compared with non-chrysene control. This study indicates the potential of these hitherto unreported tropical bacterial strains as chrysene degraders and their use in biodegradation processes involvingpetrochemical product

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Analysis of meteorology-chemistry interactions during air pollution episodes using online coupled models within AQMEII Phase-2

This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).This study reviews the top ranked meteorology and chemistry interactions in online coupled models recommended by an experts’ survey conducted in COST Action EuMetChem and examines the sensitivity of those interactions during two pollution episodes: the Russian forest fires 25 Jul -15 Aug 2010 and a Saharan dust transport event from 1 Oct -31 Oct 2010 as a part of the AQMEII phase-2 exercise. Three WRF-Chem model simulations were performed for the forest fire case for a baseline without any aerosol feedback on meteorology, a simulation with aerosol direct effects only and a simulation including both direct and indirect effects. For the dust case study, eight WRF-Chem and one WRF-CMAQ simulations were selected from the set of simulations conducted in the framework of AQMEII. Of these two simulations considered no feedbacks, two included direct effects only and five simulations included both direct and indirect effects. The results from both episodes demonstrate that it is important to include the meteorology and chemistry interactions in online-coupled models. Model evaluations using routine observations collected in AQMEII phase-2 and observations from a station in Moscow show that for the fire case the simulation including only aerosol direct effects has better performance than the simulations with no aerosol feedbacks or including both direct and indirect effects. The normalized mean biases are significantly reduced by 10-20% for PM10 when including aerosol direct effects. The analysis for the dust case confirms that models perform better when including aerosol direct effects, but worse when including both aerosol direct and indirect effects, which suggests that the representation of aerosol indirect effects needs to be improved in the model.Peer reviewedFinal Published versio

CHANG-ES XI: Circular Polarization in the Cores of Nearby Galaxies

We detect 5 galaxies in the CHANG-ES (Continuum Halos in Nearby Galaxies -- an EVLA Survey) sample that show circular polarization (CP) at L-band in our high resolution data sets. Two of the galaxies (NGC~4388 and NGC~4845) show strong Stokes $V/I\,\equiv\,m_C\,\sim\,2$\%, two (NGC~660 and NGC~3628) have values of $m_C\sim \,0.3$\%, and NGC~3079 is a marginal detection at $m_C\sim \,0.2$\%. The two strongest $m_C$ galaxies also have the most luminous X-ray cores and the strongest internal absorption in X-rays. We have expanded on our previous Faraday conversion interpretation and analysis and provide analytical expressions for the expected $V$ signal for a general case in which the cosmic ray electron energy spectral index can take on any value. We provide examples as to how such expressions could be used to estimate magnetic field strengths and the lower energy cutoff for CR electrons. Four out of our detections are {\it resolved}, showing unique structures, including a {\it jet} in NGC~4388 and a CP `conversion disk' in NGC~4845. The conversion disk is inclined to the galactic disk but is perpendicular to a possible outflow direction. Such CP structures have never before been seen in any galaxy to our knowledge. None of the galaxy cores show linear polarization at L-band. Thus CP may provide a unique probe of physical conditions deep into radio AGNs.Comment: 30 pages, 4 figures, accepted to MNRA

Acupuncture treatment for idiopathic Horner's syndrome in a dog

A one-year-old female English Cocker Spaniel dog with idiopathic Horner's Syndrome is described. The specific clinical signs in this specimen were miosis, ptosis, enophthalmos, and prolapsed nictitans for 2 days following sudden onset. According to history taking, ophthalmic, neurological, and radiological examination, the patient was diagnosed with idiopathic Horner's syndrome. Manual acupuncture treatment was applied to the dog on local points two times in 2 days. The local acupoints were ST-4 (Di Chang) and GB-1 (Tong Zi Liao). The day after the initial acupuncture treatment, clinical signs related to idiopathic Horner's syndrome had almost disappeared. The day after the second treatment, specific clinical signs were completely absent. During this period, the dog did not receive any orthodox treatment. Thus, it is suggested that manual acupuncture might be an effective therapy for idiopathic Horner's syndrome

Dose-dependent effects of Allopurinol on human foreskin fibroblast cell and human umbilical vein endothelial cell under hypoxia

Allopurinol, an inhibitor of xanthine oxidase, has been used in clinical trials of patients with cardiovascular and chronic kidney disease. These are two pathologies with extensive links to hypoxia and activation of the transcription factor hypoxia inducible factor (HIF) family. Here we analysed the effects of allopurinol treatment in two different cellular models, and their response to hypoxia. We explored the dose-dependent effect of allopurinol on Human Foreskin Fibroblasts (HFF) and Human Umbilical Vein Endothelial Cells (HUVEC) under hypoxia and normoxia. Under normoxia and hypoxia, high dose allopurinol reduced the accumulation of HIF-1α protein in HFF and HUVEC cells. Allopurinol had only marginal effects on HIF-1α mRNA level in both cellular systems. Interestingly, allopurinol effects over the HIF system were independent of prolyl-hydroxylase activity. Finally, allopurinol treatment reduced angiogenesis traits in HUVEC cells in an in vitro model. Taken together these results indicate that high doses of allopurinol inhibits the HIF system and pro-angiogenic traits in cells

A Case of Catecholaminergic Polymorphic Ventricular Tachycardia

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a familial cardiac arrhythmia that is related to RYR2 or CASQ2 gene mutation. It occurs in patients with structurally normal heart and causes exercise-emotion-triggered syncope and sudden cardiac death. We experienced a case of CPVT in an 11 year-old female patient who was admitted for sudden cardiovascular collapse. The initial electrocardiogram (ECG) on emergency department revealed ventricular fibrillation. After multiple defibrillations, sinus rhythm was restored. However, recurrent ventricular fibrillation occurred during insertion of nasogastric tube without sedation in coronary care unit. On ECG monitoring, bidirectional ventricular tachycardia occurred with sinus tachycardia and then degenerated into ventricular fibrillation. To our knowledge, there has been no previous case report of CPVT triggered by sinus tachycardia in Korea. Therefore, we report the case as well as a review of the literature

Characterization of Extragalactic 24micron Sources in the Spitzer First Look Survey

In this Letter, we present the initial characterization of extragalactic 24um sources in the Spitzer First Look Survey (FLS) by examining their counterparts at 8um and R-band. The color-color diagram of 24-to-8 vs. 24-to-0.7um is populated with 18,734 sources brighter than the 3sigma flux limit of 110uJy, over an area of 3.7sq.degrees. The 24-to-0.7um colors of these sources span almost 4 orders of magnitudes, while the 24-to-8um colors distribute at least over 2 orders of magnitudes. In addition to identifying ~30% of the total sample with infrared quiescent, mostly low redshift galaxies, we also found that: (1) 23% of the 24um sources (~1200/sq.degrees) have very red 24-to-8 and 24-to-0.7 colors and are probably infrared luminous starbursts with L(IR)>3x10^(11)Lsun at z>1. In particular, 13% of the sample (660/sq.degrees) are 24um detected only, with no detectable emission in either 8um or R-band. These sources are the candidates for being ULIRGs at z>2. (2) 2% of the sample (85/sq.degrees) have colors similar to dust reddened AGNs, like Mrk231 at z~0.6-3. (3) We anticipate that some of these sources with extremely red colors may be new types of sources, since they can not be modelled with any familiar type of spectral energy distribution. We find that 17% of the 24um sources have no detectable optical counterparts brighter than R limit of 25.5mag. Optical spectroscopy of these optical extremely faint 24um sources would be very difficult, and mid-infrared spectroscopy from the Spitzer would be critical for understanding their physical nature (Abridged).Comment: Accepted for publication in ApJ (Spitzer Special Issue