1,836 research outputs found
Disk-Magnetosphere Interaction and Outflows: Conical Winds and Axial Jets
We investigate outflows from the disk-magnetosphere boundary of rotating
magnetized stars in cases where the magnetic field of a star is bunched into an
X-type configuration using axisymmetric and full 3D MHD simulations. Such
configuration appears if viscosity in the disk is larger than diffusivity, or
if the accretion rate in the disk is enhanced. Conical outflows flow from the
inner edge of the disk to a narrow shell with an opening angle 30-45 degrees.
Outflows carry 0.1-0.3 of the disk mass and part of the disk's angular momentum
outward. Conical outflows appear around stars of different periods, however in
case of stars in the "propeller" regime, an additional - much faster component
appears: an axial jet, where matter is accelerated up to very high velocities
at small distances from the star by magnetic pressure force above the surface
of the star. Exploratory 3D simulations show that conical outflows are
symmetric about rotational axis of the disk even if magnetic dipole is
significantly misaligned. Conical outflows and axial jets may appear in
different types of young stars including Class I young stars, classical T Tauri
stars, and EXors.Comment: Invited review, conference proceedings of the meeting "Protostellar
Jets in Context", 7-12 July 2008, island of Rhodes, Greece; editors: profs.
Tom Ray and Kanaris Tsinganos; 10 pages, 10 figures, see animations at
http://www.astro.cornell.edu/~romanova/conical.htm and
http://www.astro.cornell.edu/~romanova/propeller.ht
TRPA1 Mediates Mechanical Currents in the Plasma Membrane of Mouse Sensory Neurons
Mechanosensitive channels serve as essential sensors for cells to interact with their environment. The identity of mechanosensitive channels that underlie somatosensory touch transduction is still a mystery. One promising mechanotransduction candidate is the Transient Receptor Potential Ankyrin 1 (TRPA1) ion channel. To determine the role of TRPA1 in the generation of mechanically-sensitive currents, we used dorsal root ganglion (DRG) neuron cultures from adult mice and applied rapid focal mechanical stimulation (indentation) to the soma membrane. Small neurons (diameter <27 Âľm) were studied because TRPA1 is functionally present in these neurons which largely give rise to C-fiber afferents in vivo. Small neurons were classified by isolectin B4 binding
The prevalence and experience of Australian naturopaths and Western herbalists working within community pharmacies
<p>Abstract</p> <p>Background</p> <p>Naturopaths and Western herbal medicine (WHM) practitioners were surveyed to identify their extent, experience and roles within the community pharmacy setting and to explore their attitudes to integration of complementary medicine (CM) practitioners within the pharmacy setting.</p> <p>Method</p> <p>Practising naturopaths and WHM practitioners were invited to participate in an anonymous, self-administered, on-line survey. Participants were recruited using the mailing lists and websites of CM manufacturers and professional associations.</p> <p>Results</p> <p>479 practitioners participated. 24% of respondents (n = 111) reported they had worked in community pharmacy, three-quarters for less than 5 years. Whilst in this role 74% conducted specialist CMs sales, 62% short customer consultations, 52% long consultations in a private room and 51% staff education. This was generally described as a positive learning experience and many appreciated the opportunity to utilise their specialist knowledge in the service of both customers and pharmacy staff. 14% (n = 15) did not enjoy the experience of working in pharmacy at all and suggested pharmacist attitude largely influenced whether the experience was positive or not. Few practitioners were satisfied with the remuneration received. 44% of the total sample provided comment on the issue of integration into pharmacy, with the main concern being the perceived incommensurate paradigms of practice between pharmacy and naturopathy. Of the total sample, 38% reported that they would consider working as a practitioner in retail pharmacy in future.</p> <p>Conclusions</p> <p>The level of integration of CM into pharmacy is extending beyond the mere stocking of supplements. Naturopaths and Western Herbalists are becoming utilised in pharmacies</p
Feasibility investigation of direct laser cutting process of metal foam with high pore density
To avoid damage to the pore structure of metal foam, a laser cutting process for efficiently and directly cutting metal foam into regular shapes is proposed. After analyzing the proposed laser cutting process, its effects when applied to three different types of metal material (copper, ferroalloy, and nickel) and two levels of pore density, namely 90 and 110 pores per inch (PPI), were investigated. The results show that metal foam with a good surface quality can be obtained without damaging the pore structure by using the proposed laser cutting process. Of the three metal types considered, the highest material removal rate (MRR) and material oxidation rate (MOR) were observed for ferroalloy foam. Of the two pore densities, metal foam of 90 PPI showed a larger material removal rate than metal foam of 110 PPI. The MRR and MOR increased with an increase in the laser output power and decrease in the scanning speed. Using a central composite experimental design method, optimized processing parameters of 26 W laser output power and 475 mm/s scanning speed were adopted to cut the metal foam with a high pore density
Azimuthal anisotropy of charged particles at high transverse momenta in PbPb collisions at sqrt(s[NN]) = 2.76 TeV
The azimuthal anisotropy of charged particles in PbPb collisions at
nucleon-nucleon center-of-mass energy of 2.76 TeV is measured with the CMS
detector at the LHC over an extended transverse momentum (pt) range up to
approximately 60 GeV. The data cover both the low-pt region associated with
hydrodynamic flow phenomena and the high-pt region where the anisotropies may
reflect the path-length dependence of parton energy loss in the created medium.
The anisotropy parameter (v2) of the particles is extracted by correlating
charged tracks with respect to the event-plane reconstructed by using the
energy deposited in forward-angle calorimeters. For the six bins of collision
centrality studied, spanning the range of 0-60% most-central events, the
observed v2 values are found to first increase with pt, reaching a maximum
around pt = 3 GeV, and then to gradually decrease to almost zero, with the
decline persisting up to at least pt = 40 GeV over the full centrality range
measured.Comment: Replaced with published version. Added journal reference and DO
Search for new physics with same-sign isolated dilepton events with jets and missing transverse energy
A search for new physics is performed in events with two same-sign isolated
leptons, hadronic jets, and missing transverse energy in the final state. The
analysis is based on a data sample corresponding to an integrated luminosity of
4.98 inverse femtobarns produced in pp collisions at a center-of-mass energy of
7 TeV collected by the CMS experiment at the LHC. This constitutes a factor of
140 increase in integrated luminosity over previously published results. The
observed yields agree with the standard model predictions and thus no evidence
for new physics is found. The observations are used to set upper limits on
possible new physics contributions and to constrain supersymmetric models. To
facilitate the interpretation of the data in a broader range of new physics
scenarios, information on the event selection, detector response, and
efficiencies is provided.Comment: Published in Physical Review Letter
Compressed representation of a partially defined integer function over multiple arguments
In OLAP (OnLine Analitical Processing) data are analysed in an n-dimensional cube. The cube may be represented as a partially defined function over n arguments. Considering that often the function is not defined everywhere, we ask: is there a known way of representing the function or the points in which it is defined, in a more compact manner than the trivial one
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
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