Results 41 to 50 of about 910,963 (262)

Effects of Biological Sex and Age on Cerebrospinal Fluid Markers—A Retrospective Observational Study

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Cerebrospinal fluid (CSF) analysis is a key diagnostic tool for neurological diseases. To date, only a few studies have investigated in larger cohorts the effect of age and biological sex on diagnostic markers extracted from CSF. Methods For this retrospective observational study, 4163 CSF findings (2012–2020) were evaluated.
Isabel‐Sophie Hafer, Simon Faissner, Ralf Gold, Aiden Haghikia   +3 more
wiley   +1 more source

Positive Definite $\ell_1$ Penalized Estimation of Large Covariance Matrices [PDF]

, 2012
The thresholding covariance estimator has nice asymptotic properties for estimating sparse large covariance matrices, but it often has negative eigenvalues when used in real data analysis.
Ma, Shiqian, Xue, Lingzhou, Zou, Hui
core  

Simulations of Wide-Field Weak Lensing Surveys II: Covariance Matrix of Real Space Correlation Functions

, 2011
Using 1000 ray-tracing simulations for a {\Lambda}-dominated cold dark model in Sato et al. (2009), we study the covariance matrix of cosmic shear correlation functions, which is the standard statistics used in the previous measurements.
Albrecht, Albrecht, Cooray, Doré, Eisenstein, Hamana, Hicken, Hu, Jarvis, Kaiser, Komatsu, Mantz, Masahiro Takada, Masanori Sato, Miyazaki, Okumura, Perlmutter, Refregier, Riess, Sato, Seo, Spergel, Takahashi, Takahiko Matsubara, Takashi Hamana, Taruya, Van Waerbeke, Van Waerbeke, Vikhlinin, White   +29 more
core   +1 more source

Association of CDKN2A/B Homozygous Deletion and Extent of Resection With Survival of Patients With WHO CNS5 Grade 4 Astrocytoma

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objectives WHO grade 4 astrocytomas are associated with poor prognosis, and their prognostic factors remain controversial. This study aimed to identify the prognostic factors and develop a management algorithm for these patients. Methods This study retrospectively included 151 CNS5 adult grade 4 astrocytomas from two medical centers.
Jiawei Cai, Guanglin Zhu, Qiu He, Chen Luo, Lingyun Zhuo, Xingfu Wang, Yiming Chen, Xiaoyong Chen, Wendong You, Jiaheng Xu, Yuanxiang Lin, Dezhi Kang, Shuai Wu, Zanyi Wu   +13 more
wiley   +1 more source

Numerical Covariance Evaluation for Linear Structures Subject to Non-Stationary Random Inputs

Computation
Random vibration analysis is a mathematical tool that offers great advantages in predicting the mechanical response of structural systems subjected to external dynamic loads whose nature is intrinsically stochastic, as in cases of sea waves, wind ...
M. Domaneschi, R. Cucuzza, L. Sardone, S. Londoño Lopez, M. Movahedi, G. C. Marano   +5 more
doaj   +1 more source

Cooperative coevolution algorithm with covariance analysis for differential evolution

Tongxin xuebao, 2023
With the increase of the number of decision variables, cooperative coevolution algorithm is easy to fall into local optimization in the process of searching the global optimal solution in large-scale high-dimensional optimization problems.Based on this ...
Bin WANG, Lu REN, Xiaofan WANG, Yajuan CAO   +3 more
doaj  

High-Dimensional Quadratic Discriminant Analysis Under Spiked Covariance Model

IEEE Access, 2020
Quadratic discriminant analysis (QDA) is a widely used classification technique that generalizes the linear discriminant analysis (LDA) classifier to the case of distinct covariance matrices among classes.
Houssem Sifaou, Abla Kammoun, Mohamed-Slim Alouini   +2 more
doaj   +1 more source

Permutation Variation and Alternative Hyper-Sphere Decomposition

Mathematics, 2022
Current covariance modeling methods work well in longitudinal data analysis. In the analysis of data with no nature order, a common covariance modeling method would be inadequate.
Qingze Li, Jianxin Pan
doaj   +1 more source

CX3CL1 in Early Detection of Alzheimer's Disease: Plasma Dynamics Across Age and Disease Stages

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Backgrounds Alzheimer's disease (AD) is characterized by amyloid‐beta plaques, tau tangles, and neuroinflammation. C‐X3‐C motif chemokine ligand 1 (CX3CL1, also known as fractalkine), a neuroimmune chemokine implicated in AD pathogenesis, shows inconsistent alterations in plasma/serum across studies.
Ling Wang, Yujie Liu, Fei Li, Xuelin Li, Lanlan Li, Jie Zhang, Yali Xu   +6 more
wiley   +1 more source

Baseline Regional Cholinergic Denervation Predicts Cognitive Trajectories in Moderate Parkinson Disease

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Cognitive decline is a disabling and variable feature of Parkinson disease (PD). While cholinergic system degeneration is linked to cognitive impairments in PD, most prior research reported cross‐sectional associations. We aimed to fill this gap by investigating whether baseline regional cerebral vesicular acetylcholine transporter ...
Taylor Brown, Giulia Carli, Prabesh Kanel, Stiven Roytman, Jaimie Barr, Nicolaas I. Bohnen, Roger L. Albin   +6 more
wiley   +1 more source