Search results for "matrix"
showing 10 items of 3205 documents
Consequences of forest landscape changes on the availability of winter pastures for reindeer (Rangifer tarandus tarandus) from 1953 to 2003 in Kuusam…
2013
Modelling of rotations by using matrix solutions of nonlinear wave equations
2007
A family of matrix solutions of nonlinear wave equations is extended and its application to modelling is given. It is shown that a similarity transformation, induced by the matrix solution, is equivalent to the rotation. Matrix solutions are used for modelling helical motions and vortex rings, simultaneous rotations and particles collision, mapping contraction and pulsating spheres. Geometrical interpretation of the doubling of rotation angle in each step of sequential mapping contraction is given. First Published Online: 14 Oct 2010
Calculating the implied correlation matrix for a Path Analysis model
2014
To overcome the limitations of two existing methods for calculating a Path Analysis implied correlation matrix, this paper presents an alternative method for calculating this matrix. This new method is based on a recurrence principle which is easy and quick to implement. This method is also operational regardless of the number of variables. The consequences of this result with the estimation or testing stages will be illustrated on the basis of examples.
Possible role of differential metalloproteinase 1 expression in signet ring cell and intestinal colorectal carcinoma histotypes
2008
Background: Pure signet ring cell colorectal carcinoma ( SRCC) is an infrequent and highly malignant histological variant of colorectal cancer (CRC), while it is present as a histological component in colorectal carcinomas more frequently. Materials and Methods: The aim of this was to widen the knowledge of the biological factors involved in the pathogenesis and aggressiveness of SRCC by the identification and evaluation of possible molecular abnormalities. By means of immunohistochemistry the expression of the proteolytic degradation enzyme matrix metalloprotease (MMP)-1, that is a collagenase specifically degrading collagens I, II, III and of the adhesion proteins E-cadherin, B-catenin an…
Role of Natural Cross Linkers in Resin–Dentin Bond Durability: A Systematic Review and Meta-Analysis
2022
Background: The role of endogenous Matrix Metallo Proteinases in resin dentin bond deterioration over time has been well documented. The present study aimed to systematically review the literature; in vitro and ex vivo studies that assessed the outcomes of natural cross-linkers for immediate and long-term tensile bond strength were included. Methods: The manuscript search was carried out in six electronic databases—PubMed/MEDLINE, LILACS, SciELO, Cochrane, Web of Science and DOAJ, without publication year limits. Only manuscripts in English (including the translated articles) were selected, and the last search was performed in December 2020. The Preferred Reporting Items for Systematic Revi…
Prognostic and functional significant of mmp2 and mmp9 in breast cancer unveiled by proteomic analysis
2022
Data from: From cacti to carnivores: improved phylotranscriptomic sampling and hierarchical homology inference provide further insight into the evolu…
2019
Premise of the Study— The Caryophyllales contains ~12,500 species and is known for its cosmopolitan distribution, convergence of trait evolution, and extreme adaptations. Some relationships within the Caryophyllales, like those of many large plant clades, remain unclear and phylogenetic studies often recover alternative hypotheses. We explore the utility of broad and dense transcriptome sampling across the order for resolving evolutionary relationships in Caryophyllales. Methods— We generated 84 transcriptomes and combined these with 224 publicly available transcriptomes to perform a phylogenomic analysis of Caryophyllales. To overcome the computational challenge of ortholog detection in su…
Data from: Specimens at the center: an informatics workflow and toolkit for specimen-level analysis of public DNA database data
2017
Major public DNA databases — NCBI GenBank, the DNA DataBank of Japan (DDBJ), and the European Molecular Biology Laboratory (EMBL) — are invaluable biodiversity libraries. Systematists and other biodiversity scientists commonly mine these databases for sequence data to use in phylogenetic studies, but such studies generally use only the taxonomic identity of the sequenced tissue, not the specimen identity. Thus studies that use DNA supermatrices to construct phylogenetic trees with species at the tips typically do not take advantage of the fact that for many individuals in the public DNA databases, several DNA regions have been sampled; and for many species, two or more individuals have been…
Some observations on the use of matrix modifiers in the determination of aluminum by electrothermal atomic absorption spectrophotometry
1989
Abstract Some evidence demonstrating that the use of matrix modifiers is necessary to obtain good calibration lines in the determination of aluminum by graphite furnace atomic absorption spectrophotometry is provided. It was found that the most sensitive results were obtained when Mg(NO 3 ) 2 was used instead of NH 4 H 2 PO 4 .
Identical fits of nonnegative matrix/tensor factorization may correspond to different extracted event-related potentials
2010
Nonnegative Matrix / Tensor factorization (NMF/NTF) have been used in the study of EEG, and the fit (explained variation) is often used to evaluate the performance of a nonnegative decomposition algorithm. However, this parameter only reveals the information derived from the mathematical model and just exhibits the reliability of the algorithms, and the property of EEG can not be reflected. If fits of two algorithms are identical, it is necessary to examine whether the desired components extracted by them are identical too. In order to verify this doubt, we performed NMF and NTF on the same dataset of an auditory event-related potentials (ERPs), and found that the identical fits of NMF and …