1,856 research outputs found
Lab Management Decisions Under DRG's
The change to a prospective payment system tor Medicare and Medicaid patients has forced hospital laboratories to adopt new management strategies. This paper examines those strategies and proposes that hospitals that are more stressed under the new payment system will adopt more of these strategies. Data is gathered through a survey of four hospitals in a local service area, and analyzed to test the hypotheses.Master of Public AdministrationPublic AdministrationUniversity of Michigan-Flinthttps://deepblue.lib.umich.edu/bitstream/2027.42/143446/1/Heiman.pd
Antiferromagnetic phase of the gapless semiconductor V3Al
Discovering new antiferromagnetic compounds is at the forefront of developing
future spintronic devices without fringing magnetic fields. The
antiferromagnetic gapless semiconducting D03 phase of V3Al was successfully
synthesized via arc-melting and annealing. The antiferromagnetic properties
were established through synchrotron measurements of the atom-specific magnetic
moments, where the magnetic dichroism reveals large and oppositely-oriented
moments on individual V atoms. Density functional theory calculations confirmed
the stability of a type G antiferromagnetism involving only two-third of the V
atoms, while the remaining V atoms are nonmagnetic. Magnetization, x-ray
diffraction and transport measurements also support the antiferromagnetism.
This archetypal gapless semiconductor may be considered as a cornerstone for
future spintronic devices containing antiferromagnetic elements.Comment: Accepted to Physics Review B on 02/23/1
Genetic components affecting the interval between consecutive inseminations
International audienc
Prediction of Ferromagnetic Ground State of NaCl-type FeN
Ab-initio results for structural and electronic properties of NaCl-type FeN
are presented in a framework of plane-wave and ultrasoft pseudopotentials.
Competition among different magnetic ordering is examined. We find the
ferromagnetic phase stable overall. Stabilization over the unpolarized phase is
obtained by splitting one flat t_2g-type band crossing the Fermi energy. A
comparison with CrN is considered. We find large differences in the properties
of the two systems that can be addressed to the smaller ionicity and
magnetization of FeN.Comment: 5 pages, 4 figures, twocolumn latex style Sentence changed in Section
III line 1
Magnetic Interactions and Transport in (Ga,Cr)As
The magnetic, transport, and structural properties of (Ga,Cr)As are reported.
Zincblende GaCrAs was grown by low-temperature molecular beam
epitaxy (MBE). At low concentrations, x0.1, the materials exhibit unusual
magnetic properties associated with the random magnetism of the alloy. At low
temperatures the magnetization M(B) increases rapidly with increasing field due
to the alignment of ferromagnetic units (polarons or clusters) having large
dipole moments of order 10-10. A standard model of
superparamagnetism is inadequate for describing both the field and temperature
dependence of the magnetization M(B,T). In order to explain M(B) at low
temperatures we employ a distributed magnetic moment (DMM) model in which
polarons or clusters of ions have a distribution of moments. It is also found
that the magnetic susceptibility increases for decreasing temperature but
saturates below T=4 K. The inverse susceptibility follows a linear-T
Curie-Weiss law and extrapolates to a magnetic transition temperature
=10 K. In magnetotransport measurements, a room temperature resistivity
of =0.1 cm and a hole concentration of cm
are found, indicating that Cr can also act as a acceptor similar to Mn. The
resistivity increases rapidly for decreasing temperature below room
temperature, and becomes strongly insulating at low temperatures. The
conductivity follows exp[-(T/T)] over a large range of
conductivity, possible evidence of tunneling between polarons or clusters.Comment: To appear in PRB 15 Mar 200
Phenotype of Transgenic Mice Carrying a Very Low Copy Number of the Mutant Human G93A Superoxide Dismutase-1 Gene Associated with Amyotrophic Lateral Sclerosis
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease of the motor neuron. While most cases of ALS are sporadic, 10% are familial (FALS) with 20% of FALS caused by a mutation in the gene that codes for the enzyme Cu/Zn superoxide dismutase (SOD1). There is variability in sporadic ALS as well as FALS where even within the same family some siblings with the same mutation do not manifest disease. A transgenic (Tg) mouse model of FALS containing 25 copies of the mutant human SOD1 gene demonstrates motor neuron pathology and progressive weakness similar to ALS patients, leading to death at approximately 130 days. The onset of symptoms and survival of these transgenic mice are directly related to the number of copies of the mutant gene. We report the phenotype of a very low expressing (VLE) G93A SOD1 Tg carrying only 4 copies of the mutant G93ASOD1 gene. While weakness can start at 9 months, only 74% of mice 18 months or older demonstrate disease. The VLE mice show decreased motor neurons compared to wild-type mice as well as increased cytoplasmic translocation of TDP-43. In contrast to the standard G93A SOD1 Tg mouse which always develops motor weakness leading to death, not all VLE animals manifested clinical disease or shortened life span. In fact, approximately 20% of mice older than 24 months had no motor symptoms and only 18% of VLE mice older than 22 months reached end stage. Given the variable penetrance of clinical phenotype, prolonged survival, and protracted loss of motor neurons the VLE mouse provides a new tool that closely mimics human ALS. This tool will allow the study of pathologic events over time as well as the study of genetic and environmental modifiers that may not be causative, but can exacerbate or accelerate motor neuron disease
Влияние глобальных климатических изменений на размеры косточек среднего уха
Department of Anatomy and Anthropology Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel, Department of Otorhinolaryngology Head Neck Surgery, The Sheba Medical Center, Tel-Hashomer, Conferinţa Știinţifică Internaţională ”Probleme actuale ale morfologiei” dedicată сentenarului profesorului B.Z. Perlin, Chişinău, 20-22 septembrie 2012Abstract
Hypothesis: The morphology of middle ear ossicles varies between people living in different climatic regions.
Background: The differences between climatic conditions in different world regions have a morphological and physiological influence on human development. The present study is aimed to investigate morphological variations of middle-ear
ossicles collected from different geographic locations on the globe. Methods: Middle ear ossicles (total samples 631) were
collected from 6 different geographic regions: Australia, Chile, France, India, Israel and Kenya. Latitude and longitude,
and climatic parameters (mean temperature, humidity and daylight duration of the warmer and colder months, and altitude
above sea level) were collected for each region. The associations between middle ear ossicles’ dimensions and climate were
evaluated using Pearson’s correlations. Results: Significant differences between samples of middle ear ossicles’ characteristics were found. Correlations between the ‘above sea level’ altitude and longitudinal sizes of the malleus, incus and
stapes were negative. Correlations between warm temperature and longitudinal sizes of the malleus, incus and stapes were
positive. Conclusions: Differences in characteristics of middle ear ossicles encountered between territorial samples could
be the result of climatic variations.
Гипотеза: морфология косточек среднего уха отличается у людей, живущих в различных климатических районах.
Справочная информация: различия климатических условий в различных регионах мира имеют морфологические и
физиологические воздействие на развитие человека. Данное исследование направлено на исследование морфологических изменений косточек среднего уха, собранных в различных географических точках земного шара. Методы:
косточки среднего уха (всего 631 образец) были собраны в 6 различных географических регионах: Австралия, Чили,
Франция, Индия, Израиль и Кения. Широта и долгота, климатические параметры (средняя температура, влажность
и продолжительность светового дня теплых и холодных месяцев, высота над уровнем моря) были определены для
каждого региона. Связь между размерами косточек среднего уха и климатом были оценены с использованием корреляции Пирсона. Результат: были найдены значительные различия в характеристиках образцов косточек среднего
уха. Корреляция между «над уровнем моря» и продольными размерами молоточка, наковальни и стремечка были
обратнопропорциональными. Корреляция между теплой температурой и продольными размерами слуховых косточек
были прямопропорциональными. Выводы: Различия в характеристиках косточек среднего уха различных территориальных образцов могут быть результатом климатических изменений
Theory of anyon excitons: Relation to excitons of nu=1/3 and nu=2/3 incompressible liquids
Elementary excitations of incompressible quantum liquids (IQL's) are anyons,
i.e., quasiparticles carrying fractional charges and obeying fractional
statistics. To find out how the properties of these quasiparticles manifest
themselves in the optical spectra, we have developed the anyon exciton model
(AEM) and compared the results with the finite-size data for excitons of nu=1/3
and nu=2/3 IQL's. The model considers an exciton as a neutral composite
consisting of three quasielectrons and a single hole. The AEM works well when
the separation between electron and hole confinement planes, h, is larger than
the magnetic length l. In the framework of the AEM an exciton possesses
momentum k and two internal quantum numbers, one of which can be chosen as the
angular momentum, L, of the k=0 state. Existence of the internal degrees of
freedom results in the multiple branch energy spectrum, crater-like electron
density shape and 120 degrees density correlations for k=0 excitons, and the
splitting of the electron shell into bunches for non-zero k excitons. For h
larger than 2l the bottom states obey the superselection rule L=3m (m are
integers starting from 2), all of them are hard core states. For h nearly 2l
there is one-to-one correspondence between the low-energy spectra found for the
AEM and the many- electron exciton spectra of the nu=2/3 IQL, whereas some
states are absent from the many-electron spectra of the nu=1/3 IQL. We argue
that this striking difference in the spectra originates from the different
populational statistics of the quasielectrons of charge conjugate IQL's and
show that the proper account of the statistical requirements eliminates
excessive states from the spectrum. Apparently, this phenomenon is the first
manifestation of the exclusion statistics in the anyon bound states.Comment: 26 pages with 9 figures, typos correcte
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