31 research outputs found
Direct comparison of Neuroform and Enterprise stents in the treatment of wide-necked intracranial aneurysms
To compare the complications and outcomes of Neuroform and Enterprise stents in the treatment of unruptured wide-necked aneurysms.
Under the auspices of the institutional review board, a review of a prospectively collected patient log identified 130 patients who underwent elective stent-assisted coil embolization of a wide-necked aneurysm, including 53 patients treated with an Enterprise stent and 77 patients treated with a Neuroform stent. Immediate and long-term clinical and radiographic outcomes were recorded for all patients. All patient data were handled in accordance with Health Insurance Portability and Accountability Act of 1996 (HIPAA) regulations.
The technical success rate was 94%. Overall morbidity was 15% with Enterprise stents and 3% with Neuroform stents (p = 0.020). However, the type of stent used was not predictive of clinical outcomes as measured by the modified Rankin scale. In a multivariate analysis, the use of a Neuroform stent was one of the predictors of retreatment (p = 0.034).
Multivariate analyses identified the use of Neuroform stents as an independent predictor of the need for retreatment and the use of Enterprise stents as an independent predictor of morbidity. However, the type of stent was not predictive of clinical outcome as measured by the modified Rankin scale.
•The use of Enterprise stents was an independent predictor of morbidity.•The use of Neuroform stents was an independent predictor for retreatment.•The type of stent was not predictive of clinical outcome as measured by the mRS
Helmintos oxiuridae parasitos de Iguana iguana (Squamata, Lacertilia, Iguanidae) procedentes do Brasil
Nitrogen pools and fluxes in grassland soils sequestering carbon
Carbon sequestration in agricultural, forest, and grassland soils has been promoted as a means by which substantial amounts of CO2 may be removed from the atmosphere, but few studies have evaluated the associated impacts on changes in soil N or net global warming potential (GWP). The purpose of this research was to ( 1) review the literature to examine how changes in grassland management that affect soil C also impact soil N, ( 2) assess the impact of different types of grassland management on changes in soil N and rates of change, and (3) evaluate changes in N2O fluxes from differently managed grassland ecosystems to assess net impacts on GWP. Soil C and N stocks either both increased or both decreased for most studies. Soil C and N sequestration were tightly linked, resulting in little change in C: N ratios with changes in management. Within grazing treatments N2O made a minor contribution to GWP (0.1-4%), but increases in N2O fluxes offset significant portions of C sequestration gains due to fertilization (10-125%) and conversion (average = 27%). Results from this work demonstrate that even when improved management practices result in considerable rates of C and N sequestration, changes in N2O fluxes can offset a substantial portion of gains by C sequestration. Even for cases in which C sequestration rates are not entirely offset by increases in N2O fluxes, small increases in N2O fluxes can substantially reduce C sequestration benefits. Conversely, reduction of N2O fluxes in grassland soils brought about by changes in management represents an opportunity to reduce the contribution of grasslands to net greenhouse gas forcing
Organizational Responses to Strategic Issues Posed by the Natural Environment: An Application of Miles and Snow's Strategic Types
Note on arXiv:2005.05301, 'Preparation of the Neutrino-4 experiment on search for sterile neutrino and the obtained results of measurements'
We comment on the claimed observation [arXiv:arXiv:2005.05301] of sterile neutrino oscillations by the Neutrino-4 collaboration. Such a claim, which requires the existence of a new fundamental particle, demands a level of rigor commensurate with its impact. The burden lies with the Neutrino-4 collaboration to provide the information necessary to prove the validity of their claim to the community. In this note, we describe aspects of both the data and analysis method that might lead to an oscillation signature arising from a null experiment and describe additional information needed from the Neutrino-4 collaboration to support the oscillation claim. Additionally, as opposed to the assertion made by the Neutrino-4 collaboration, we also show that the method of 'coherent summation' using the parameter produces similar results to the methods used by the PROSPECT and the STEREO collaborations