40 research outputs found
Inverting multivariate analytic characteristic functions with financial applications
No full textThis dissertation is devoted to multivariate analytic characteristic functions inversion and applications in option pricing, option sensitivities estimation, and some electronic engineering problems. We will show that under certain analytic conditions for characteristic functions, the underlying pdfs and cdfs have exponential tails. The inversion from multivariate characteristic functions to the corresponding pdfs and cdfs can be approximated by the trapezoidal rule conveniently with great accuracy. Monte Carlo methods can be applied for option sensitivity analysis. Under multi-dimensional models, acceptance-rejection method is desirable. Simulating from a distribution without explicit pdf or CDF is then transformed to sampling from an easy-to-simulate distribution. Detailed algorithms are provided and comparisons against classical methods in terms of accuracy and efficiency are included.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2021-05-01The student, Runqi Hu, accepted the attached license on 2019-04-19 at 10:23.The student, Runqi Hu, submitted this Dissertation for approval on 2019-04-19 at 10:32.This Dissertation was approved for publication on 2019-04-19 at 14:25.DSpace SAF Submission Ingestion Package generated from Vireo submission #13740 on 2019-08-22 at 15:07:23Made available in DSpace on 2019-08-23T20:36:02Z (GMT). No. of bitstreams: 2
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Previous issue date: 2019-04-19Embargo set by: Seth Robbins for item 112175
Lift date: 2021-08-23T20:36:18Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemU of I Only Restriction Lifted for Item 112175 on 2021-08-24T09:15:20Z
Impact of Changing Trends in Medical Therapy on Transurethral Resection of the Prostate: Two Decades of Change in China
No full textOBJECTIVE To retrospectively assess that over the 2 decades, whether medical therapy has changed indications, patient characteristics, and outcomes in men undergoing transurethral resection of the prostate (1992-2013). METHODS At our institution, medical history of all patients undergoing surgery before 1998, between 2001 and 2003, and between 2011 and 2013 was reviewed. Patient demographics, preoperative clinical profile, clinical management, and operative complications were assessed. RESULTS A total of 1157 patients were enrolled in the study. Mean ages of patients increased from 67.0 to 70.4 years old over the past 2 decades. Furthermore, comorbidities increased significantly as well. Although prostate size and weight of resected tissue increased from 57.3 to 92.3 g and from 24.3 to 36.6 g, the surgical time decreased from 78.21 to 72.29 minutes. From 2011 to 2013, patients undergoing surgery had their catheters remove earlier (from 5.7 to 4.5 days), whose postoperative days in hospital were shorter (from 9.3 to 4.4 days). Although operative complications decreased from 12.3% to 5.7%, especially bleeding, re-operation due to bleeding increased from 0.4% to 2.7%. Moreover, no statistical difference was observed in operative complications between patients with medical therapy and those without medical therapy. CONCLUSION The increasing application of medical therapy resulted in surgical interventions delay. The prostate size was significantly greater, as was the weight of resected tissue. Although patients with medication were older with more comorbidities and larger prostates, surgical technique advancements have benefited them and transurethral resection of the prostate is still considered as a safe and recommendable surgical treatment. (C) 2016 Elsevier Inc.SCI(E)[email protected]
Research trends on alphavirus receptors: a bibliometric analysis
No full textBackgroundAlphaviruses are a diverse group of pathogens that have garnered considerable attention due to their impact on human health. By investigating alphavirus receptors, researchers can elucidate viral entry mechanisms and gain important clues for the prevention and treatment of viral diseases. This study presents an in-depth analysis of the research progress made in the field of alphavirus receptors through bibliometric analysis.MethodsThis study encompasses various aspects, including historical development, annual publication trends, author and cited-author analysis, institutional affiliations, global distribution of research contributions, reference analysis with strongest citation bursts, keyword analysis, and a detailed exploration of recent discoveries in alphavirus receptor research.ResultsThe results of this bibliometric analysis highlight key milestones in alphavirus receptor research, demonstrating the progression of knowledge in this field over time. Additionally, the analysis reveals current research hotspots and identifies emerging frontiers, which can guide future investigations and inspire novel therapeutic strategies.ConclusionThis study provides an overview of the state of the art in alphavirus receptor research, consolidating the existing knowledge and paving the way for further advancements. By shedding light on the significant developments and emerging areas of interest, this study serves as a valuable resource for researchers, clinicians, and policymakers engaged in combating alphavirus infections and improving public health
Correlation of ASA Grade and the Charlson Comorbidity Index With Complications in Patients After Transurethral Resection of Prostate
No full textOBJECTIVE To re-assess the Charlson Comorbidity Index (CCI) and the American Society of Anesthesiologists Physical Status Classification System (ASA grade) as predictive factors of complications after transurethral resection of prostate. METHODS This study retrospectively included and analyzed consecutive patients undergoing transurethral resection of the prostate at Peking University First Hospital between 1992 and 2013. A multi-variate analysis was conducted to evaluate the connection of the ASA and CCI grades with the incidence of complications. RESULTS This paper studied 2326 cases in total. The CCI and ASA grades were significantly correlated, with a Spearman rho of 0.245 (P <.001). No considerable differences among the patient cohorts with different CCI or ASA grades were observed in terms of day of catheter removal, surgical time, and prostate size. In addition, no considerable differences were observed in the different modified Clavien classification system scores of complications among patient cohorts with different grades of CCI. CONCLUSION The majority of complications (86.9%) were of grades I, II, and III, whereas grade IV was less frequent (12.1%), and, after transurethral resection of the prostate, grade V was rare (1%). Males with an ASA grade >= 3 and higher CCI scores were more likely to demonstrate a higher incidence of morbidity than males with a lower grade. However, ASA grades and CCI scores were not independent predictors of complications because of the experience of the surgeon and progress in perioperative management and operative techniques. Therefore, for patients with more comorbidities and higher CCI scores or ASA grades, active surgical intervention is still suggested. (C) 2016 Elsevier Inc.SCI(E)[email protected]
Searching for Exotic Spin-Dependent Interactions with Diamond-Based Vector Magnetometer
No full textWe propose a new method to search for exotic spin-spin interactions between
electrons and nucleons using a diamond-based vector magnetometer. The vector
magnetometer can be constructed from ensembles of nitrogen-vacancy centers
along different axes in a diamond. The nuclear spins of
nitrogen-vacancy centers in the same diamond can be polarized through the
dynamic nuclear polarization method to serve as spin sources. With the vector
magnetometer, the sought-after exotic interactions can be distinguished from
the magnetic dipole-dipole interaction. For the axion-mediated interaction , new upper bounds of the coupling are
expected within the force range from 10 nm to 100 m. For the -mediated interaction , new upper bounds of the coupling are expected within the force range from 10 nm to 1 cm.
The new upper bounds for and are both expected to be more
than 5 orders of magnitude more stringent than existing constraints at the
force range of 1 m with the total measurement time of one day
MP83-03 DETECTION OF UROTHELIAL CARCINOMA USING SELECTED URINE-DNA METHYLATION BIOMARKERS IN PATIENTS WITH GROSS HEMATURIA: A PROSPECTIVE, SINGLE-CENTER STUDY
No full textResearch Progress on Slip Behavior of α-Ti under Quasi-Static Loading: A Review
No full textThis paper reviews the dislocation slip behavior of α phase in α, near α and α + β titanium alloys dominated by α-Ti deformation under quasi-static loading. The relation of slip activity, slip transfer, slip blocking, twinning and crack initiation is discussed, mainly combined with in situ tensile technology. The slip behavior in Ti-alloys is analyzed in detail from the aspects of critical resolved shear stress (CRSS), grain orientation distribution and geometric compatibility factor m′. In addition, slip blocking is an important factor of the formation of twins and micro-cracks. The interaction of slip behavior and interfaces is clarified systematically. Finally, the insufficiency of current research, future research directions and key difficulties of study are also discussed
Additively manufactured Nb-Ti-Si based alloy: As-built and heat-treated conditions
No full textThis work aims to fully characterise the Nb-Ti-Si based alloy (Nb-26Ti-16Si-2.2Al-2Cr), processed by the electron-beam powder-bed-fusion in both as-built and heat-treated conditions, to elucidate the microstructure-property relationships. The as-built condition has [001]-oriented columnar grains of the Nb3Si phase with the Nbss phase dispersed throughout the microstructure. The microhardness is 645.2 ± 6.7 HV0.5, and the indentation fracture toughness shows distinct directionality: 7.7 MPa·m1/2 in the horizontal direction compared to 5.3 MPa·m1/2 in the vertical direction. Both properties are comparable to the cast version. The directionality is attributed to the underlying mechanisms such as crack bridging, arrest, and micro-crack formation. By contrast, in the heat-treated condition, the alloy exhibits a dual-phase microstructure (Nbss and Nb5Si3 phases) with near-equiaxed grain shape due to the Nb3Si phase decomposition. The fracture toughness increases to 12.1 MPa·m1/2, at the expense of a reduced microhardness of 564.4 ± 15.0 HV0.5
