5,717 research outputs found
Redescription of Hypoptopoma inexspectata (Holmberg, 1883), with notes on its anatomy (Siluriformes: Loricariidae).
Hypoptopoma inexspectata is diagnosed and redescribed based on the examination of additional
material and comparison with its congeners. This poorly known hypoptopomine species is distributed in the
Paraguay and Paraná river draÃnages. Hypoptopoma inexspectata is diagnosable based on the
autapomorphy biserial arrangement of anterior snout rostral margin odontodes, laterally extended to limit
between second and third infraorbital plates, with dorsally directed dorsad series separated from ventrally
directed ventrad series by a narrow odontode-free area, which at the level of first and second infraorbital
plates is reduced to a dividing line of the series. The species can be further distinguished by the
combination (1) low number of canal-bearing lateral plates (20-22, typically 21), (2) presence of a shield of
prepectoral dermal plates, (3) arrangement of abdominal plates in one paired series of 3-5 plates, (4)
shorter least interorbital distance 4856% head lengh, (5) larger horizontal eye diameter 17-20% head lengh,
and (6) least orbit-nare distance 812% head lengh. Intraspecific variation skull dermal bones, neuracranium
and suspensorium bones, dermal plates, adipose fin is reported. (PDF has 20 pages.
Three flavor neutrino oscillations in matter
We derive analytic expressions for three flavor neutrino oscillations in the
presence of matter in the plane wave approximation using the Cayley-Hamilton
formalism. Especially, we calculate the time evolution operator in both flavor
and mass bases. Furthermore, we find the transition probabilities, matter mass
squared differences, and matter mixing angles all expressed in terms of the
vacuum mass squared differences, the vacuum mixing angles, and the matter
density. The conditions for resonance in the presence of matter are also
studied in some examples.Comment: 25 pages, 6 figures (PostScript), RevTe
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Idiopathic Bilateral Internal Jugular Vein Thrombosis Diagnosed by Point-of-Care Ultrasound
Internal jugular vein (IJV) thrombosis is an unusual condition, especially when it develops bilaterally. This is a case of bilateral IJV thrombosis in a 77-year old female who presented to the emergency department with neck and arm swelling after discontinuing apixaban and undergoing an oropharyngeal procedure. The diagnosis of bilateral IJV thrombosis was made with the use of point-of-care ultrasound to evaluate bilateral jugular vein distention and bilateral upper extremity pitting edema found on her physical examination
The Diamine Cation Is Not a Chemical Example Where Density Functional Theory Fails
In a recent communication, Weber and co-workers presented a surprising study
on charge-localization effects in the N,N'-dimethylpiperazine (DMP+) diamine
cation to provide a stringent test of density functional theory (DFT) methods.
Within their study, the authors examined various DFT methods and concluded that
"all DFT functionals commonly used today, including hybrid functionals with
exact exchange, fail to predict a stable charge-localized state." This
surprising conclusion is based on the authors' use of a self-interaction
correction (namely, complex-valued Perdew-Zunger Self-Interaction Correction
(PZ-SIC)) to DFT, which appears to give excellent agreement with experiment and
other wavefunction-based benchmarks. Since the publication of this recent
communication, the same DMP+ molecule has been cited in numerous subsequent
studies as a prototypical example of the importance of self-interaction
corrections for accurately calculating other chemical systems. In this
correspondence, we have carried out new high-level CCSD(T) analyses on the DMP+
cation to show that DFT actually performs quite well for this system (in
contrast to their conclusion that all DFT functionals fail), whereas the PZ-SIC
approach used by Weber et al. is the outlier that is inconsistent with the
high-level CCSD(T) (coupled-cluster with single and double excitations and
perturbative triples) calculations. Our new findings and analysis for this
system are briefly discussed in this correspondence.Comment: Accepted by Nature Communication
Characteristics of Children Attending Asthma Camp in Nevada
The purpose of this study was to assess asthma trigger knowledge of camp attendees and the measure of agreement between physician and parent assessment of the children’s asthma severity. This study is based on cross-sectional data provided by the American Lung Association (ALA) and those children participating in summer asthma camps in Las Vegas and Reno, Nevada. Fifty-six children participated in the camp in August of 2008. The study results suggest a significant positive correlation between physician and parent assessment of asthma severity. With increasing asthma severity there was a relative increase in the number of school days missed among attendees. Trigger knowledge was low among 25.9% (n=7) of attendees, 40.7% (n= 11) had moderate trigger knowledge, and only 33% (n= 9) demonstrated adequate trigger knowledge. Asthma camp is an effective venue to improve asthma education among children and provide a clinical assessment of this condition among those that are without a current diagnosis
Classical properties of algebras using a new graph association
We study the relation between algebraic structures and Graph Theory. We have
defined five different weighted digraphs associated to a finite dimensional
algebra over a field in order to tackle important properties of the associated
algebras, mainly the nilpotency and solvability in the case of Leibniz
algebras
Aproximative solutions to the neutrino oscillation problem in matter
We present approximative solutions to the neutrino evolution equation
calculated by different methods. In a two neutrino framework, using the
physical parameters which gives the main effects to neutrino oscillations from
nu{e} to another flavors for L=3000Km and E=1GeV, the results for the
transition probability calculated by using series solutions, by to take the
neutrino evolution operator as a product of ordered partial operators and by
numerical methods, for a linearly and sinusoidally varying matter density are
compared. The extension to an arbitrary density profile is discussed and the
evolution operator as a product of partial operators in the three neutrino case
is obtained.Comment: 12 pages, 5 figure
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