475 research outputs found
Higher order Dependency of Chaotic Maps
Some higher-order statistical dependency aspects
of chaotic maps are presented. The autocorrelation
function (ACF) of the mean-adjusted squares, termed the
quadratic autocorrelation function, is used to access nonlinear
dependence of the maps under consideration. A simple
analytical expression for the quadratic ACF has been
found in the case of fully stretching piece-wise linear maps.
A minimum bit energy criterion from chaos communications
is used to motivate choosing maps with strong negative
quadratic autocorrelation. A particular map in this
class, a so-called deformed circular map, is derived which
performs better than other well-known chaotic maps when
used for spreading sequences in chaotic shift-key communication
systems
Optimal Spreading Sequences for Chaos-Based Communication Systems
As a continuation from [2], some higherorder
statistical dependency aspects of chaotic spreading
sequences used in communication systems are presented.
The autocorrelation function (ACF) of the mean-adjusted
squares, termed the quadratic autocorrelation function,
forms the building block of nonlinear dependence assessment
of the family of spreading sequences under investigation.
Explicit results are provided for the theoretical lower
bound, the so-called Fr´echet lower bound, of the quadratic
ACF of that family. A method for producing a spreading
sequence which attains the Fr´echet bound is introduced
Superior Semicircular Canal Dehiscence in a Patient with Ehlers-Danlos Syndrome: A Case Report.
Superior semicircular canal dehiscence (SSCD) is a bony defect in the middle cranial fossa floor that results in an abnormal connection between the inner ear and cranial vault. Although the etiology of SSCD remains unclear, an inappropriately thin or fragile temporal bone likely predisposes an individual towards developing SSCD. Ehlers-Danlos syndrome (EDS) constitutes a group of genetic connective tissue disorders caused by a defect in the production, processing, or structure of collagen, or its associated proteins. The possible association between SSCD and EDS has not been previously described in the literature. We herein report a case of a 50-year-old female with EDS-hypermobility type who presented with a 15-year history of migraines, vertigo, and tinnitus. The patient was subsequently diagnosed with bilateral SSCD and underwent a right middle fossa (pre-auricular infratemporal) craniotomy for SSCD repair. She reported significant improvement in her auditory and vestibular symptoms, with the exception of continued mild dizziness and disequilibrium at the 3-month follow-up. Due to the rare reports of auditory symptoms in EDS, this case study highlights the importance of considering an otological consultation for auditory manifestations in a patient with EDS and illustrates a potential association between EDS and SSCD
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Systematic Analysis of Clinical Outcomes Following Stereotactic Radiosurgery for Central Neurocytoma.
Central neurocytoma (CN) typically presents as an intraventricular mass causing obstructive hydrocephalus. The first line of treatment is surgical resection with adjuvant conventional radiotherapy. Stereotactic radiosurgery (SRS) was proposed as an alternative therapy for CN because of its lower risk profile. The objective of this systematic analysis is to assess the efficacy of SRS for CN. A systematic analysis for CN treated with SRS was conducted in PubMed. Baseline patient characteristics and outcomes data were extracted. Heterogeneity and publication bias were also assessed. Univariate and multivariate linear regressions were used to test for correlations to the primary outcome: local control (LC). The estimated cumulative rate of LC was 92.2% (95% confidence interval: 86.5-95.7%, p<0.001). Mean follow-up time was 62.4 months (range 3-149 months). Heterogeneity and publication bias were insignificant. The univariate linear regression models for both mean tumor volume and mean dose were significantly correlated with improved LC (p<0.001). Our data suggests that SRS may be an effective and safe therapy for CN. However, the rarity of CN still limits the efficacy of a quantitative analysis. Future multi-institutional, randomized trials of CN patients should be considered to further elucidate this therapy
Vortex fluidic mediated synthesis of TiO2 nanoparticle/MXene composites
Oxidation of MXene in a vortex fluidic device (VFD) operating under continuous flow results in exfoliation and fragmentation into nanoparticles of surface oxidised 2D material with further oxidation of the nanoparticles into anatase (TiO 2 ). These MXene and anatase nanoparticles co‐assemble into stable micron sized spheres which are topologically smooth, decorating the surface of exfoliated MXene. The formation of this composite material in the dynamic thin film in the VFD was optimised by systematically exploring the operating parameters of the microfluidic platform, determined at 45 o tilt angle for the 20 mm diamater glass tube spinning at 5k rpm, with a flow rate of a colloidal dispersion of MXene in aqueous H 2 O 2 (30%) at 0.75 mL/min, concentration of MXene 0.5 mg/mL
African Asylum at a Crossroads: Activism, Expert Testimony, and Refugee Rights
African Asylum at a Crossroads: Activism, Expert Testimony, and Refugee Rights examines the emerging trend of requests for expert opinions in asylum hearings or refugee status determinations. This is the first book to explore the role of court-based expertise in relation to African asylum cases and the first to establish a rigorous analytical framework for interpreting the effects of this new reliance on expert testimony.
Over the past two decades, courts in Western countries and beyond have begun demanding expert reports tailored to the experience of the individual claimant. As courts increasingly draw upon such testimony in their deliberations, expertise in matters of asylum and refugee status is emerging as an academic area with its own standards, protocols, and guidelines. This deeply thoughtful book explores these developments and their effects on both asylum seekers and the experts whose influence may determine their fate.
Contributors: Iris Berger, Carol Bohmer, John Campbell, Katherine Luongo, E. Ann McDougall, Karen Musalo, Tricia Redeker Hepner, Amy Shuman, Joanna T. Tague, Meredith Terretta, and Charlotte Walker-Said.https://ohioopen.library.ohio.edu/oupress/1023/thumbnail.jp
Portmanteau tests for linearity of Stationary Time Series
This paper considers the problem of testing for linearity of stationary time series. Portmanteau tests are discussed which are based on generalized correlations of residuals from a linear model (that is, autocorrelations and cross-correlations of different powers of the residuals). The finite-sample properties of the tests are assessed by means of Monte Carlo experiments. The tests are applied to 100 time series of stock returns
Central Neurocytoma: A Review of Clinical Management and Histopathologic Features.
Central neurocytoma (CN) is a rare, benign brain tumor often located in the lateral ventricles. CN may cause obstructive hydrocephalus and manifest as signs of increased intracranial pressure. The goal of treatment for CN is a gross total resection (GTR), which often yields excellent prognosis with a very high rate of tumor control and survival. Adjuvant radiosurgery and radiotherapy may be considered to improve tumor control when GTR cannot be achieved. Chemotherapy is also not considered a primary treatment, but has been used as a salvage therapy. The radiological features of CN are indistinguishable from those of other brain tumors; therefore, many histological markers, such as synaptophysin, can be very useful for diagnosing CNs. Furthermore, the MIB-1 Labeling Index seems to be correlated with the prognosis of CN. We also discuss oncogenes associated with these elusive tumors. Further studies may improve our ability to accurately diagnose CNs and to design the optimal treatment regimens for patients with CNs
An online version of the Mooney Face Test: phenotypic and genetic associations.
The Mooney Face Test is a widely used test of face perception, but was originally designed to be administered by personal interview. We have developed a three-alternative forced-choice version for online testing. We tested 397 healthy adults between the ages of 18 and 42 (M=24 years). There was a wide range of performance (64-100% correct; M=89.6%). We observed a significant sex difference favoring males (.31 standard deviation; p =.004). In addition, independently of sex, higher 2D:4D digit ratios were significantly associated with higher scores (ρ=.14, p=.006). A genome-wide association study (GWAS) for a subset of 370 participants identified an association between Mooney performance and a polymorphism in the RAPGEF5 gene (rs1522280; p=9.68×10(-8)). This association survives a permutation test (p=.031).This is the author's accepted manuscript. The final version of this paper is published by Elsevier in Neuropsychologia here: http://www.sciencedirect.com/science/article/pii/S0028393214002747
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