1,257 research outputs found
Produção e avaliação da qualidade do leite na microrregião de Castanhal.
bitstream/item/63529/1/Oriental-Doc95.PD
The Distance to the Soft Gamma Repeater SGR 1627-41
We report millimeter observations of the line of sight to the recently
discovered Soft Gamma Repeater, SGR 1627-41, which has been tentatively
associated with the supernova remnant SNR G337.0-0.1 Among the eight molecular
clouds along the line of sight to SGR 1627-41, we show that SNR G337.0-0.1 is
probably interacting with one of the most massive giant molecular clouds (GMC)
in the Galaxy, at a distance of 11 kpc from the sun. Based on the high
extinction to the persistent X-ray counterpart of SGR 1627-41, we present
evidence for an association of this new SGR with the SNR G337.0-0.1; they both
appear to be located on the near side of the GMC. This is the second SGR
located near an extraordinarily massive GMC. We suggest that SGR 1627-41 is a
neutron star with a high transverse velocity (~ 1,000 \kms) escaping the young
(~ 5,000 years) supernova remnant G337.0-0.1Comment: 17 pages, including 2 figures. Accepted for publication in the
Astrophysical Journal Letter
Lifetimes of Confined Acoustic Phonons in Ultra-Thin Silicon Membranes
We study the relaxation of coherent acoustic phonon modes with frequencies up
to 500 GHz in ultra-thin free-standing silicon membranes. Using an ultrafast
pump-probe technique of asynchronous optical sampling, we observe that the
decay time of the first-order dilatational mode decreases significantly from
\sim 4.7 ns to 5 ps with decreasing membrane thickness from \sim 194 to 8 nm.
The experimental results are compared with theories considering both intrinsic
phonon-phonon interactions and extrinsic surface roughness scattering including
a wavelength-dependent specularity. Our results provide insight to understand
some of the limits of nanomechanical resonators and thermal transport in
nanostructures
A Amazônia pode se tornar uma grande região de pecuária bovina sustentável?
A biblioteca possui o trabalho completo, copiado de CD-ROM (SP 4937
Results of vascular resections during pancreatectomy from two European centres: an analysis of survival and disease-free survival explicative factors
AbstractObjectives. The object of our study was to report on the experience with vascular resections at pancreatectomy in two European specialist hepatopancreatobiliary centres and evaluate outcome and prognostic factors. Patients and methods. From 1989 to 2002, 45 patients (21 men, 24 women) underwent pancreatectomy for a pancreatic mass: Whipple's procedure (n= 33), total pancreatectomy (n= 10) or left splenopancreatectomy (n= 2), along with a vascular resection, i.e. venous (n= 39), arterial (n= 1) or venous + arterial (n= 5). Results. Operative mortality was nil, postoperative mortality was 2.2% (n= 1); 34 patients had an uneventful postoperative course. Reoperations were performed for portal vein thromobosis (n= 1), pancreatic leak (n= 1), gastric outlet syndrome (n= 1) and gastrointestinal bleeding (n= 1). In all, 43 patients had cancer on pathology examination, with retropancreatic invasion in 72% and lymph node extension in 62.8%. Resection was R0 in 21 cases. Vessel wall invasion was present in 13 cases and 19 had perivascular invasion. Disease-free survival (DFS) at 1, 2 and 3 years was 36.0%, 15.0% and 12.0%, respectively. Median DFS length was 8.7 months (95% CI: 7.2; 10.2). Overall survival rates were 56.6%, 28.9% and 19.2%, respectively. Median survival length was 14.2 months (95% CI: 9.8; 18.6). A multivariate analysis of prognostic variables identified tumour location (other than head of pancreas), neoadjuvant chemotherapy and advanced disease stage as adverse factors for DFS. Conclusion. Survival and DFS rates of these patients are comparable to those without vascular resection. Tumour localization, tumour stage, neoadjuvant treatment and tumour recurrence are explanatory variables of survival. Tumour localization, tumour stage and neoadjuvant treatment were explanatory variables for DFS. However, the type and extent of vascular resections as well as vessel wall invasion does not affect survival and DFS
Primary Invasive Aspergillosis of the Digestive Tract: Report of Two Cases and Review of the Literature
Abstract : Background: : Disseminated aspergillosis is thought to occur as a result of vascular invasion from the lungs with subsequent bloodstream dissemination, and portals of entry other than sinuses and/or the respiratory tract remain speculative. Methods: : We report two cases of primary aspergillosis in the digestive tract and present a detailed review of eight of the 23 previously-published cases for which detailed data are available. Results and Conclusion: : These ten cases presented with symptoms suggestive of typhlitis, with further peritonitis requiring laparotomy and small bowel segmental resection. All cases were characterized by the absence of pulmonary disease at the time of histologically-confirmed gastrointestinal involvement with vascular invasion by branched Aspergillus hyphae. These cases suggest that the digestive tract may represent a portal of entry for Aspergillus species in immunocompromised patient
SPI observations of positron annihilation radiation from the 4th galactic quadrant: sky distribution
During its first year in orbit the INTEGRAL observatory performed deep
exposures of the Galactic Center region and scanning observations of the
Galactic plane. We report on the status of our analysis of the positron
annihilation radiation from the 4th Galactic quadrant with the spectrometer
SPI, focusing on the sky distribution of the 511 keV line emission. The
analysis methods are described; current constraints and limits on the Galactic
bulge emission and the bulge-to-disk ratio are presented.Comment: 4 pages, 2 figures, accepted for publication in the proceedings of
the 5th INTEGRAL worksho
A cadeia produtiva do leite: uma alternativa para consolidar a agricultura familiar nas frentes pioneiras da Amazônia?
Publicado também em SAYAGO, D.; TOURRAND, J.-F.; BURSZTYN, M. (Org.). Amazônia: cenas e cenários. Brasília, DF: UnB, 2004. p. 115-137
Cadeia produtiva do leite: alternativa para consolidação da agricultura familiar nas frentes pioneiras da Amazônia.
bitstream/item/63532/1/Oriental-Doc114.PD
- …