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Multi-factor models are useful tools to explain cross-sectional covariance in equities returns. In this paper a new estimation method is proposed that makes use of irregularly spaced returns and an empirical example is provided with the 389 most liquid equities in the Brazilian Market. The market index shows itself capable of explaining equity returns while the US$/Brazilian real exchange rate and the Brazilian short interest rate do not. The example shows the usefulness of the estimation method in further using the model to fill in missing values and to provide interval forecasts. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the impact of number of vessels targeted by fenestrations or branches on early outcomes of fenestrated-branched endovascular aortic repair (F-BEVAR) for complex abdominal aortic aneurysms (cAAAs)., Methods: The clinical data of 260 patients (209 men; mean, 74 ± 7 years) treated for cAAAs in four academic centers using fenestrated-branched stent grafts with one to five fenestrations or branches were entered into prospectively maintained databases (2010-2015). Data were analyzed in patients treated with ≤2-vessel (group 1, n = 124), 3-vessel (group 2, n = 80), or ≥4 fenestrations or directional branches (group 3, n = 56). For group definition, only vessels incorporated by fenestrations or directional branches were accounted. End points were technical success, procedural variables, 30-day mortality, and major adverse events (MAEs)., Results: A total of 830 vessels (mean, 3.19 ± 0.8 vessels/patient) were targeted by fenestrations (n = 672), scallops (n = 136), or branches (n = 22). Two-vessel designs were used more often in the early experience (64%), whereas ≥3-vessel design (groups 2 and 3) was preferred in the late experience (68%, P < 0.05). Patients with ≥4-vessel designs had longer operating and fluoroscopy time (+78 min, P < 0.0001 and + 27 min, P < 0.001), higher volume of contrast use (+31 mL, P = 0.03), and longer hospital stay (+3 days, P = 0.007) of those who had ≤2-vessel designs. Technical success, estimated blood loss, mortality, MAEs, and rate of spinal cord injury were similar in all three groups (P > 0.05)., Conclusions: F-BEVAR for complex abdominal aortic aneurysms was associated with high technical success and low 30-day mortality and morbidity. Increasing complexity was associated with longer operating and fluoroscopy time, more contrast use, and longer hospital stay but did not affect technical success and MAEs of the procedure., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: The study purpose was to review the outcomes of patients treated for thoracoabdominal aortic aneurysms using endovascular repair with fenestrated and branched stent-grafts in a single center., Methods: We reviewed the clinical data of the first 185 consecutive patients (134 male; mean age, 75 ± 7 years) treated for thoracoabdominal aortic aneurysms using fenestrated and branched stent-grafts. Graft design evolved from physician-modified endografts (2007-2013) to off-the-shelf or patient-specific manufactured devices in patients enrolled in a prospective physician-sponsored investigational device exemption protocol (NCT 1937949 and 2089607). Outcomes were reported for extent IV and extent I to III thoracoabdominal aortic aneurysms, including 30-day mortality, major adverse events, patient survival, primary target vessel patency, and reintervention., Results: A total of 112 patients (60%) were treated for extent IV thoracoabdominal aortic aneurysms, and 73 patients (40%) were treated for extent I to III thoracoabdominal aortic aneurysms. Demographics and cardiovascular risk factors were similar in both groups. A total of 687 renal-mesenteric arteries (3.7 vessels/patient) were targeted by 540 fenestrations and 147 directional branches. Technical success was 94%. Thirty-day mortality was 4.3%, including a mortality of 1.8% for extent IV and 8.2% for extent I to III thoracoabdominal aortic aneurysms (P = .03). Mortality decreased in the second half of clinical experience from 7.5% to 1.2%, including a decrease of 3.3% to 0% for extent IV thoracoabdominal aortic aneurysms (P = .12) and 15.6% to 2.4% for extent I to III thoracoabdominal aortic aneurysms (P = .04). Early major adverse events occurred in 36 patients (32%) with extent IV thoracoabdominal aortic aneurysms and 26 patients (36%) with extent I to III thoracoabdominal aortic aneurysms, including spinal cord injury in 2 patients (1.8%) and 4 patients (3.2%), respectively. Mean follow-up was 21 ± 20 months. At 5 years, patient survival (56% and 59%, P = .37) and freedom from any reintervention (50% and 53%, P = .26) were similar in those with extent IV and extent I to III thoracoabdominal aortic aneurysms. Primary patency was 93% at 5 years., Conclusions: Endovascular repair of thoracoabdominal aortic aneurysms can be performed with high technical success and low mortality and morbidity. However, the need for secondary reinterventions and continued graft surveillance represents major limitations compared with results of conventional open surgical repair. Long-term follow-up is needed before the widespread use of these techniques in younger or lower-risk patients., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

In contrast with the previous criteria published in 1984 by the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association, the new criteria proposed in 2007 incorporated in the diagnostic framework the use of biomarkers that are able to assess the underlying pathophysiologic mechanism. The combination of clinical and biologic approaches makes a diagnosis of Alzheimer's disease possible before the dementia stage. The core clinical criteria continue to be the cornerstone of the diagnosis in clinical practice, but biomarker evidence is expected to enhance the specificity for the diagnosis of Alzheimer's disease., (Copyright © 2012 Elsevier Inc. All rights reserved.)