6,589 research outputs found
On the very long term evolutionary behavior of hydrogen-accreting Low-Mass CO white dwarfs
Hydrogen-rich matter has been added to a CO white dwarf of initial mass 0.516
\msun at the rates and \msun \yrm1, and results are
compared with those for a white dwarf of the same initial mass which accretes
pure helium at the same rates. For the chosen accretion rates, hydrogen burns
in a series of recurrent mild flashes and the ashes of hydrogen burning build
up a helium layer at the base of which a He flash eventually occurs. In
previous studies involving accretion at higher rates and including initially
more massive WDs, the diffusion of energy inward from the H shell-flashing
region contributes to the increase in the temperature at the base of the helium
layer, and the mass of the helium layer when the He flash begins is
significantly smaller than in a comparison model accreting pure helium; the He
shell flash is not strong enough to develop into a supernova explosion. In
contrast, for the conditions adopted here, the temperature at the base of the
He layer becomes gradually independent of the deposition of energy by H shell
flashes, and the mass of the He layer when the He flash occurs is a function
only of the accretion rate, independent of the hydrogen content of the accreted
matter. When the He flash takes place, due to the high degeneracy at the base
of the He layer, temperatures in the flashing zone will rise without a
corresponding increase in pressure, nuclear burning will continue until nuclear
statistical equilibrium is achieved; the model will become a supernova, but not
of the classical type Ia variety.Comment: 14 pages and 3 Postscript figures, Accepted for publication on ApJ
Letter
The electronic structures and magnetic properties of perovskite ruthenates from constrained orbital hybridization calculations
We introduce a method to analyze the effect of hybridization by shifting
corresponding atomic levels using external potentials. Based on this approach,
we study perovskite ruthenates,\ and unambiguously identify that the covalency
between the \textit{A}-site cation and O ion will modify the Ru-O hybridization
and change the density of state at Fermi level, consequently affect the
magnetic properties significantly. We also study the effect of pressure and
reveal that hydrostatic pressure has a small effect on the Ru-O-Ru bond angle
of SrRuO, while it will decrease the Ru-O length and increase the band
width significantly. Therefore, the magnetic ordering temperature will decrease
monotonically with pressure
Análisis descriptivo de intervenciones realizadas y premedicación perioperatoria en cirugia bucal en los pabellones de la facultad de odontología. Universidad Andrés Bello, sede Santiago. Periodo 2008-2013
Tesis para optar al Título de Cirujano - DentistaAbstract
In the development of clinical practice, there are many procedures that can involve dental surgery, which may have different purposes, but always focused on solving problems giving back to patients the comfort and functionality of the masticatory apparatus. After an oral surgery, the procedure can cause a number of complications such as edema, trismus and after surgery pain. To avoid this we have several measures where the use of pharmacological means is one of the major therapies, especially if it is applied within the surgical room.
FACULTAD ODONTOLOGIA , ASIGNATURA DE CIRUGÍA BUCAL Noviembre de 2014
2
The general aim of this research is to know the types of oral surgeries performed and its relation to perioperative medication in the surgical room of the Faculty of Dentistry UNAB, Santiago, between 2008 and 2013.
This non-experimental descriptive research was conducted by collecting information from Oral Surgery of the subject of surgery, made in the surgical room, of the school of Dentistry, UNAB, Santiago, in order to know the general characteristics of the interventions between 2008 and 2013; and also assess which were the most used medicines in the different procedures.
922 surgeries where performed throughout the period, where the most prevalent was the third molar surgery. Among the most commonly used medications were cefazolin, dexamethasone and ketoprofen, all intravenous route, mainly used before surgery. Also emphasize the use of oral sedation with midazolam concerning third molar surgery.
The results of this research indicate that there is no relationship between the prescribed medicine, type of surgery performed or age or gender. Instead of this, there is a standard protocol without indicating surgical procedure
Dynamic hysteresis in Finemet thin films
We performed a series of dynamic hysteresis measurements on three series of
Finemet films with composition FeCuNbSiB, using
both the longitudinal magneto-optical Kerr effect (MOKE) and the inductive
fluxometric method. The MOKE dynamic hysteresis loops show a more marked
variability with the frequency than the inductive ones, while both measurements
show a similar dependence on the square root of frequency. We analyze these
results in the frame of a simple domain wall depinning model, which accounts
for the general behavior of the data.Comment: 3 pages, 3 figure
Karakteristik Kecelakaan Lalu Lintas Dan Lokasi Black Spot Di Kab. Cilacap
Kecelakaan dan kemacetan lalu lintas merupakan dua masalah transportasi yang perlu diatasi segera. Selama tahun 2012 tercatat sebanyak 25.131 nyawa hilang akibat kecelakaan lalu lintas di jalan raya. Tujuan dari kajian ini adalah untuk menganalisis karakteristik kecelakaan lalu lintas dan melakukan identifikasi terhadap lokasi yang merupakan titik rawan kecelakaan lalu lintas. Penentuan lokasi rawan kecelakaan lalu lintas dengan menggunakan metode pembobotan angka ekivalen kecelakaan menurut Pdt T-09-2004-B tahun 2004. Berdasarkan hasil analisis diperoleh bahwa karakteristik kecelakaan lalu lintas di Kabupaten Cilacap dari tahun 2006 s.d 2008 berdasarkan jenis kelamin didominasi oleh laki-laki. Sepeda motor merupakan kendaraan yang paling banyak terlibat kecelakaan diikuti oleh mobil penumpang. Berdasarkan lokasi kecelakaan maka sebagian besar kecelakaan terjadi di ruas jalan antar kota dan faktor utama penyebab kecelakaan adalah manusia. Lokasi rawan kecelakaan lalu lintas pada ruas jalan perkotaan yaitu jalan Rinjani, jalan Urip Sumoharjo dan jalan Gatot Subroto. Lokasi rawan kecelakaan lalu lintas pada ruas jalan antar kota yaitu ruas jalan raya Jeruk Legi, ruas jalan raya Cimanggu, ruas jalan raya Purwokerto-Banjar, Kecamatan Wanareja dan ruas jalan raya Kedungreja-Tambakareja, Cilacap
Formas arcaicas y recientes de Ursus spelaeus en Lombardía y la región de Venecia (Norte de Italia)
[Abstract] Some Ursus spelaeus Rosenmüller-Heinroth, 1784 cranial and mandibular remains coming from Northern Italy (Lombardy Region -Buco dell’Orso Cave, Laglio, Como-) and from Venetia Region (Cerè, S. Donà di Lamon and Velo), are biometrically analysed. The compared fossils could be inserted in two typological forms: archaic and modern. To the first belongs a part of Venetia Region remains and to the second, the Buco dell’Orso Cave fossils and some of the Venetia Region caves too. The probable thesis of derivation of U. Spelaeus by U. Arctos is mentioned, although the phylogenetic hypothesis U. etruscus→U. deningeri→U. spelaeus, is still effective
WiQoSM: An Integrated QoS-Aware Mobility and User Behavior Model for Wireless Data Networks
Observations on the Ursus gr. spelaeus remains from the Pocala cave (Trieste, Friuli Venezia Giulia, N. Italy)
uploaded for Revue de Paléobiologie by Plaz
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