170 research outputs found
Tactics of treatment of acute left colon cancer obstruction
Back ground: Advanced colorectal cancer is commonly associated with colon obstruction/between 15-20% of patients with colonic cancer/ or/and tumor infiltration to adjacent organs. We set out to study in-hospital morbidity and mortality after operations of acute left colon cancer obstruction.Methods: From 2000 to 2010 the medical records of 204 cases /15.1%/ of acute left colon cancer obstruction were reviewed from total of 1351 patients who were operated from colorectal cancer. Results: The types of operations were a Hartmann procedure in 78 patients /38.2%/, colostomy in 58 patients /29.4%%, a type of colectomy with ileo-coloanastomosis in 54 patients /26.5%/ and a standard resection in 14 patients /6.8%/. The following early complications were occurred: anastomotic leakage in 4 patients, wound infections in 5 patients, dehiscence of operative wound in 2 patients. The in-hospital mortality rate was 11.3%.Conclusions: The emergency management of acute left-sided colonic obstruction remains controversial. The one-stage resection anastomosis which could be subtotal colectomy or segmental resection is useful and the preferred choice for low risk patients. Simple colostomy or Hartmann procedure should be re served for high risk patients. Colonic stenting is the best option either for palliation or as a bridge to surgery
Merging Galaxies in the SDSS EDR
We present a new catalog of merging galaxies obtained through an automated
systematic search routine. The 1479 new pairs of merging galaxies were found in
approximately 462 sq deg of the Sloan Digital Sky Survey Early Data Release
(SDSS EDR; Stoughton et al. 2002) photometric data, and the pair catalog is
complete for galaxies in the magnitude range 16.0 <= g* <= 20.
The selection algorithm, implementing a variation on the original
Karachentsev (1972) criteria, proved to be very efficient and fast. Merging
galaxies were selected such that the inter-galaxy separations were less than
the sum of the component galaxies' radii.
We discuss the characteristics of the sample in terms of completeness, pair
separation, and the Holmberg effect. We also present an online atlas of images
for the SDSS EDR pairs obtained using the corrected frames from the SDSS EDR
database. The atlas images also include the relevant data for each pair member.
This catalog will be useful for conducting studies of the general
characteristics of merging galaxies, their environments, and their component
galaxies. The redshifts for a subset of the interacting and merging galaxies
and the distribution of angular sizes for these systems indicate the SDSS
provides a much deeper sample than almost any other wide-area catalog to date.Comment: 58 pages, which includes 15 figures and 6 tables. Figures 2, 8, 9,
10, 11, 13, and 14 are provided as JPEG files. For online atlas, see
http://home.fnal.gov/~sallam/MergePair/ . Accepted for publication in A
Formation of a disk-structure and jets in the symbiotic prototype Z And during its 2006-2010 active phase
We present an analysis of spectrophotometric observations of the latest cycle
of activity of the symbiotic binary Z And from 2006 to 2010. We estimate the
temperature of the hot component of Z And to be \approx 150000 - 170000 K at
minimum brightness, decreasing to \approx 90000 K at the brightness maximum.
Our estimate of the electron density in the gaseous nebula is
N_{e}=10^{10}-10^{12} cm^{-3} in the region of formation of lines of neutral
helium and 10^6-10^7 cm^{-3} in the region of formation of the [OIII] and
[NeIII] nebular lines. A trend for the gas density derived from helium lines to
increase and the gas density derived from [OIII] and [NeIII] lines to
simultaneously decrease with increasing brightness of the system was observed.
Our estimates show that the ratios of the theoretical and observed fluxes in
the [OIII] and [NeIII] lines agree best when the O/Ne ratio is similar to its
value for planetary nebulae. The model spectral energy distribution showed
that, in addition to a cool component and gaseous nebula, a relatively cool
pseudophotosphere (5250-11 500 K) is present in the system. The simultaneous
presence of a relatively cool pseudophotosphere and high-ionization spectral
lines is probably related to a disk-like structure of the pseudophotosphere.
The pseudophotosphere formed very rapidly, over several weeks, during a period
of increasing brightness of Z And. We infer that in 2009, as in 2006, the
activity of the system was accompanied by a collimated bipolar ejection of
matter. In contrast to the situation in 2006, the jets were detected even
before the system reached its maximum brightness. Moreover, components with
velocities close to 1200 km/s disappeared at the maximum, while those with
velocities close to 1800 km/s appeared.Comment: 18 pages, 19 figures, Accepted for publication in Astronomy Report
Mast cell distribution around the needle tract following acupuncture in Zusanli (ST36) acupoint in rats
The aim of this study was to investigate mast cell (MCs) distribution in the vicinity of the needle tract formed after acupuncture in Zusanli (ST36) acupoint in rats. MCs were detected by histochemistry, immunohistochemistry and transmission electron microscopy, and evaluated quantitatively. It was established that after acupuncture in ST36 acupoint the integrity of the epithelium, dermis, subcutane-ous connective tissue, fascia, epimysium and striated muscles was disrupted and folded to the direc-tion of the needle tract. In the thickened connective tissue MCs were observed close to the needle tract, without visible differences in their number along the tract, but most of them were with signs of degranulation, possibly due to acupuncture. It could be presumed that acupuncture in ST36 caused recruitment and activation of MCs followed by degranulation which most probably influenced the local microenvironment
Nova light curves from the Solar Mass Ejection Imager (SMEI) - II. The extended catalogue
We present the results from observing nine Galactic novae in eruption with the Solar Mass Ejection Imager (SMEI) between 2004 and 2009. While many of these novae reached peak magnitudes that were either at or approaching the detection limits of SMEI, we were still able to produce light curves that in many cases contained more data at and around the initial rise, peak, and decline than those found in other variable star catalogs. For each nova, we obtained a peak time, maximum magnitude, and for several an estimate of the decline time (t2). Interestingly, although of lower quality than those found in Hounsell et al. (2010a), two of the light curves may indicate the presence of a pre-maximum halt. In addition the high cadence of the SMEI instrument has allowed the detection of low amplitude variations in at least one of the nova light curves
A Study of an Outburst in the Classical Symbiotic Star Z And in a Colliding-Wind Model
Two-dimensional gas-dynamical modeling of the mass-flow structure is used to
study the outburst development in the classical symbiotic star Z And. The
stage-by-stage rise of the light during the outburst can be explained in the
framework of the colliding winds model. We suggest a scenario for the
development of the outburst and study the possible influence of the changes of
the flow structure on the light of the system. The model variations of the
luminosity due to the formation of a system of shocks are in good agreement
with the observed light variations
Fast Rotation of the N=Z Nucleus 36Ar
A highly-deformed rotational band has been identified in the N=Z nucleus 36Ar. At high spin the band is observed to its presumed termination at I=16+, while at low spin it has been firmly linked to previously known states in 36Ar. Spins, parities, and absolute excitation energies have thus been determined throughout the band. Lifetime measurements establish a large low-spin quadrupole deformation (beta_2=0.46+-0.03) and indicate a decreasing collectivity as the band termination is approached. With effectively complete spectroscopic information and a valence space large enough for significant collectivity to develop, yet small enough to be meaningfully approached from the shell model perspective, this rotational band in 36Ar provides many exciting opportunities to test and compare complementary models of collective motion in nuclei
Primary Black Hole Spin in OJ 287 as Determined by the General Relativity Centenary Flare
OJ 287 is a quasi-periodic quasar with roughly 12 year optical cycles. It displays prominent outbursts that are predictable in a binary black hole model. The model predicted a major optical outburst in 2015 December. We found that the outburst did occur within the expected time range, peaking on 2015 December 5 at magnitude 12.9 in the optical R -band. Based on Swift /XRT satellite measurements and optical polarization data, we find that it included a major thermal component. Its timing provides an accurate estimate for the spin of the primary black hole, ##IMG## [http://ej.iop.org/images/2041-8205/819/2/L37/apjl523055ieqn1.gif] . The present outburst also confirms the established general relativistic properties of the system such as the loss of orbital energy to gravitational radiation at the 2% accuracy level, and it opens up the possibility of testing the black hole no-hair theorem with 10% accuracy during the present decade.Peer reviewe
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