4,146 research outputs found
Non-visualization of lung markings below hemidiaphragm in subtle subpulmonic effusion: an old sign resuscitated
To assess the lack of visibility of vascular markings under the hemidiaphragm on a frontal chest radiograph as a sign of pleural effusion, fifteen patients were collected showing this sign. Pleural effusion was diagnosed by ultrasound, comparison with previous or subsequent chest x-ray or computed tomography. Patients in the study group exhibited this sign in the absence of the classical signs of pleural effusion. In the control group, lack of visibility of blood vessels was observed in only 4.2% cases. Non-visualization of vascular markings below the hemidiaphragm should alert the interpreter to the possible presence of pleural effusion and a lateral or decubitus view or ultrasound examination may be carried out to rule out effusion
Tensor model and dynamical generation of commutative nonassociative fuzzy spaces
Rank-three tensor model may be regarded as theory of dynamical fuzzy spaces,
because a fuzzy space is defined by a three-index coefficient of the product
between functions on it, f_a*f_b=C_ab^cf_c. In this paper, this previous
proposal is applied to dynamical generation of commutative nonassociative fuzzy
spaces. It is numerically shown that fuzzy flat torus and fuzzy spheres of
various dimensions are classical solutions of the rank-three tensor model.
Since these solutions are obtained for the same coupling constants of the
tensor model, the cosmological constant and the dimensions are not fundamental
but can be regarded as dynamical quantities. The symmetry of the model under
the general linear transformation can be identified with a fuzzy analog of the
general coordinate transformation symmetry in general relativity. This symmetry
of the tensor model is broken at the classical solutions. This feature may make
the model to be a concrete finite setting for applying the old idea of
obtaining gravity as Nambu-Goldstone fields of the spontaneous breaking of the
local translational symmetry.Comment: Adding discussions on effective geometry, a note added, four
references added, other minor changes, 27 pages, 17 figure
Equivalent frame modelling of an unreinforced masonry building with flexible diaphragms - a case study
A case study was conducted to investigate the applicability of the equivalent frame modelling for the nonlinear time-history analysis of unreinforced masonry buildings with flexible diaphragms. The dynamic responses calculated from the equivalent frame models were compared against shake table test results of a full-scale two-storey stone masonry building. The investigated modelling approach reflected the simplifications commonly assumed for the global analysis of buildings; namely, considering the diaphragms to behave elastically and neglecting the stiffness and strength contributions of the out-of-plane responding walls. The sensitivity of the analysis to different idealisations of the equivalent frame, as well as to the diaphragm stiffness values, were also investigated. Discussions are provided on the accuracies and limitations of the investigated modelling approach, which may serve as a useful guidance for practical application.Yasuto Nakamura, Hossein Derakhshan, Abdul H. Sheikh, Jason M. Ingham, and Michael C. Griffit
Anomalous rotational-alignment in N=Z nuclei and residual neutron-proton interaction
Recent experiments have demonstrated that the rotational-alignment for the
nuclei in the mass-80 region is considerably delayed as compared to the
neighboring nuclei. We investigate whether this observation can be
understood by a known component of nuclear residual interactions. It is shown
that the quadrupole-pairing interaction, which explains many of the delays
known in rare-earth nuclei, does not produce the substantial delay observed for
these nuclei. However, the residual neutron-proton interaction which is
conjectured to be relevant for nuclei is shown to be quite important in
explaining the new experimental data.Comment: 4 pages, 3 figures, final version accepted by Phys. Rev. C as a Rapid
Communicatio
Percutaneous transhepatic biliary stenting
Objective: Bilary stenting with endoprosthesis is a palliative procedure to relieve malignant biliary obstruction. Percutaneous transhepatic technique has been employed whenever endoscopic technique was not possible or had failed.SETTING: Angiography/intervention suite, department of radiology, Aga Khan University hospital, Karachi.Methods: We present retrospective analysis of 17 patients with malignant jaundice who were treated with percutaneous techniques after the endoscopic route had failed.Results: The success rate was 94% with placement of single plastic stent in 14 patients, double stents in 3 patients and self-expandable stent in one patient. The overall complication rate was 41% including sepsis, liver abscess, biloma formation, biliary leakage and stent occlusion. There was one procedure related death due to severe sepsis.CONCLUSION: Percutaneous transhepatic biliary stenting is an alternative procedure to relieve malignant biliary obstruction with high complication rate and should be reserved for selected patients in whom endoscopic route has failed
and colliding in noncommutative space
By studying the scattering process of scalar particle pion on the
noncommutative scalar quantum electrodynamics, the non-commutative amendment of
differential scattering cross-section is found, which is dependent of
polar-angle and the results are significantly different from that in the
commutative scalar quantum electrodynamics, particularly when . The non-commutativity of space is expected to be explored at around
TeV.Comment: Latex, 12 page
- …