Results 111 to 120 of about 66,244 (252)

Notes On The Non Linear Operator Equation I AXAX n  *

Ibn Al-Haitham Journal for Pure and Applied Sciences, 2016
  Necessary and sufficient conditions for the operator equation I AXAX n  * , to have a real positive definite solution X are given. Based on these conditions, some properties of the operator A as well as relation between the solutions X ...
B.A. Ahmed, M.M. Hilal
doaj  

Maximization of the two-parameter multivariate normal likelihood avoiding logarithm and differentiation

Research in Statistics
We consider the classical problem of maximizing the likelihood function of the mean vector and the dispersion matrix given a sample from the family of multivariate Normal distributions.
Suman Majumdar
doaj   +1 more source

Seasonal Fluctuations of Plastochromanol‐8 and α‐Tocopherol Amounts in the Leaves of Cecropia Trees

Journal of the American Oil Chemists' Society, EarlyView.
ABSTRACT Plastochromanol‐8 (PC‐8) is a homologue of γ‐tocotrienol with a longer side chain (eight instead of three isoprene units) and therefore also a representative of the tocochromanol (vitamin E) group. PC‐8 has been determined in various plants and seeds, with Cecropia sp. leaves showing unusually high levels.
Rosalie Ormos, Jörg Rau, Walter Vetter
wiley   +1 more source

Synergistic Advanced Oxidation and Physicochemical Treatment Strategies for Antibiotic Removal and Resistance Mitigation in Water

Asia-Pacific Journal of Chemical Engineering, EarlyView.
ABSTRACT The presence of antibiotics in water not only causes environmental pollution but also increases the growth of antibiotic‐resistant bacterial genes, which pose serious threats to human beings and other water residents. Large numbers of people are reportedly affected by the resistant bacterial genes, as many broad‐spectrum antibiotics are not ...
Amir Zada, Shohreh Azizi
wiley   +1 more source

Origin, evolution and biogeographic dynamics of the European rabbit (Oryctolagus cuniculus) in Southwestern Europe

The Anatomical Record, EarlyView.
Abstract The Pleistocene is a key period for understanding the evolutionary history and palaeobiogeography of the European rabbit (Oryctolagus cuniculus). The species was first documented in southeastern Iberia at the beginning of the Middle Pleistocene and appears to have rapidly spread throughout Southwestern Europe, where it was found in numerous ...
Maxime Pelletier
wiley   +1 more source

Nasal soft‐tissue anatomy of Triceratops and other horned dinosaurs

The Anatomical Record, EarlyView.
Abstract Although ceratopsid dinosaurs possess a characteristically hypertrophied narial region, soft‐tissue anatomy associated with such a skeletal structure and their biological significance remain poorly understood. The present study provides the first comprehensive hypothesis on the soft‐tissue anatomy in the ceratopsid rostrum based on the Extant ...
Seishiro Tada, Takanobu Tsuihiji, Hiroki Ishikawa, Noriyuki Wakimizu, Soichiro Kawabe, Kodai Sakane   +5 more
wiley   +1 more source

Complementarity Problems And Positive Definite Matrices [PDF]

, 2012
The class of positive definite and positive semidefinite matrices is one of the most frequently encountered matrix classes both in theory and practice. In statistics, these matrices appear mostly with symmetry.
Bhimashankaram, P., A. L. N. Murthy, Parthasarathy, T., Murthy, G. S. R., G. S. R. Murthy, P. Bhimashankaram, T. Parthasarathy, Murthy, A. L. N.   +7 more
core   +1 more source

Interstitial Lung Disease in Antineutrophil Cytoplasmic Antibody–Associated Vasculitis: A European Multicenter Study

Arthritis &Rheumatology, EarlyView.
Objective Interstitial lung disease (ILD) can occur in association with antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV‐ILD) or as an isolated entity with positive ANCA (ANCA‐ILD). However, data on the epidemiology and outcomes of these conditions remain limited.
Aglaia Chalkia, Marusa Kotnik, Timothy J. Sadler, Spyridon Katechis, Rachel Jones, Ajay Kamath, Aladdin J. Mohammad, Sara Monti, Chetan Mukhtyar, Viral Nanda, Ioannis Petrakis, Dimitrios Petras, Ashnish Sinha, Pasupathy Sivasothy, Rona Smith, Kostas Stylianou, Dimitrios Vassilopoulos, Judith Babar, David Jayne   +18 more
wiley   +1 more source

Per‐ and Polyfluoroalkyl Substances and Knee Osteoarthritis: Data From the Osteoarthritis Initiative

Arthritis &Rheumatology, EarlyView.
Objective To examine whether concentrations of specific per‐ and polyfluoroalkyl substances (PFAS) and a mixture of PFAS relate to incident knee osteoarthritis (KOA) and knee pain progression. Methods Among a case‐cohort sample from the OA Initiative (n = 1,878), we examined associations of serum concentrations of eight PFAS with odds of developing ...
Jeffrey B. Driban, Lisa B. Rokoff, Bing Lu, Timothy E. McAlindon, Charles B. Eaton, Mary B. Roberts, Diana Mathes, Colleen Lestician, Zhijin Carrie Xu, Zhihua Tina Fan, Shawn P. O'Leary, Ida K. Haugen, Jérémie Sellam, Alice Courties, Abby F. Fleisch   +14 more
wiley   +1 more source

An Efficient Positive Definite Method for the Numerical Solution of the Advection Equation [PDF]

, 1986
A numerical Positive Definite Pseudo-Spectral (PDPS) method for the solution of the advection equation is presented. The method consists of two parts. For each time step first a solution using a pseudospectral method is computed.
Bartnicki, J.
core