Copyright (C) 2009 by the International Society for Heart and Lung Transplantation.”
“Silicon thermal conductivities are obtained from the solution of the linearized phonon Boltzmann selleck inhibitor transport equation without the use of any parameter-fitting. Perturbation theory is used to compute the strength of three-phonon and isotope scattering mechanisms. Matrix elements based on Fermi’s golden rule are computed exactly without assuming either average or mode-dependent Grueisen parameters, and with no underlying assumptions of crystal isotropy. The environment-dependent interatomic potential is employed to describe the interatomic
force constants and the perturbing Hamiltonians. A detailed methodology to accurately find three-phonon processes satisfying energy and momentum-conservation rules is also described. Bulk silicon thermal conductivity values are computed across a range of temperatures and shown to match experimental data very well. It is found that about two-thirds of the heat transport in
HSP990 cost bulk silicon may be attributed to transverse acoustic modes. Effective relaxation times and mean free paths are computed in order to provide a more complete picture of the detailed transport mechanisms and for use with carrier transport models based on the Boltzmann transport equation. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3195080]“
“Background: Airway complications are among the most challenging problems after lung transplantation. This article describes the use of a new tracheobronchial stent that can be placed and removed easily by flexible bronchoscopy.
Methods: A retrospective review was done of 24 consecutive patients requiring tracheobronchial AZD4547 ic50 stent placement after lung transplantation. A new self-expanding hybrid nitinol
stent was used, and changes in airway diameter and spirometry were assessed. Stent related complications were recorded.
Results: Between February 2007 and April 2008, 24 patients underwent stent placement, and 49 stents were placed for 36 anastomoses at risk. Indications included bronchial stenosis in 12, bronchomalacia in 12, bronchial stenosis plus bronchomalacia in 20, and partial bronchial dehiscence in 5. Adjunctive procedures included electrocautery in 1, balloon dilatation in 7, and electrocautery plus balloon dilatation in 4. The average degree of stenosis decreased from 80% to 20%. After stent placement, the average increase was 0.28 liters in forced vital capacity and 0.44 liters in forced expiratory volume in 1 second. Complications included granulation tissue formation in 10 stents, migration in 9, thick mucus formation in 2, and fracture in 3.
Conclusion: Airway complications in lung transplant patients were effectively palliated. Our complication rate with this new stent is comparable with other airway stents. This stent has the advantage of easy removability during flexible bronchoscopy if complications from the stent outweigh the benefits of palliation.