Results 51 to 60 of about 2,294,043 (337)
Linear Dimensionality Reduction: What Is Better?
DataThis research paper focuses on dimensionality reduction, which is a major subproblem in any data processing operation. Dimensionality reduction based on principal components is the most used methodology. Our paper examines three heuristics, namely Kaiser’
Mohit Baliyan, Evgeny M. Mirkes
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Principal Components Instrumental Variable Estimation [PDF]
, 2011 Instrumental variable estimators can be severely biased in finite samples when the degree of overidentification is high or when the instruments are weakly correlated with the endogenous regressors. This paper proposes an estimator based on the use of the
Smith, R.J., Winkelried, D.
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FEBS Letters, EarlyView.Atovaquone is an antimalarial requiring potentiation for sufficient efficacy. We pursued strategies to enhance its activity, showing that 4‐nitrobenzoate inhibits 4‐hydroxybenzoate polyprenyltransferase, decreasing ubiquinone biosynthesis. Since atovaquone competes with ubiquinol in mitochondria, 4‐nitrobenzoate facilitates its action, potentiating ...
Ignasi Bofill Verdaguer +7 more
wiley +1 more source
Journal of the Royal Statistical Society Series C: Applied Statistics, 2000 SUMMARY We introduce an algorithm for producing simple approximate principal components directly from a variance–covariance matrix. At the heart of the algorithm is a series of ‘simplicity preserving’ linear transformations. Each transformation seeks a direction within a two-dimensional subspace that has maximum variance.
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Robust functional principal components: A projection-pursuit approach [PDF]
, 2011 In many situations, data are recorded over a period of time and may be regarded as realizations of a stochastic process. In this paper, robust estimators for the principal components are considered by adapting the projection pursuit approach to the ...
Bali, Juan Lucas +3 more
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Reciprocal control of viral infection and phosphoinositide dynamics
FEBS Letters, EarlyView.Phosphoinositides, although scarce, regulate key cellular processes, including membrane dynamics and signaling. Viruses exploit these lipids to support their entry, replication, assembly, and egress. The central role of phosphoinositides in infection highlights phosphoinositide metabolism as a promising antiviral target.
Marie Déborah Bancilhon, Bruno Mesmin
wiley +1 more source
On the Fallibility of Principal Components in Research [PDF]
Educational and Psychological Measurement, 2016 The measurement error in principal components extracted from a set of fallible measures is discussed and evaluated. It is shown that as long as one or more measures in a given set of observed variables contains error of measurement, so also does any principal component obtained from the set. The error variance in any principal component is shown to be
Tenko, Raykov +2 more
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FEBS Letters, EarlyView.Phototrophs evolved light‐harvesting systems adapted for efficient photon capture in habitats enriched in far‐red radiation. A subset of eukaryotic pigment‐binding proteins can absorb far‐red photons via low‐energy chlorophyll states known as red forms.
Antonello Amelii +8 more
wiley +1 more source
Mitochondrial fatty acid oxidation is stimulated by red light irradiation
FEBS Letters, EarlyView.Light at different wavelengths has distinct effects on keratinocyte viability and metabolism. UVA light abrogates metabolic fluxes. Blue and green light have no effect on metabolic fluxes, while red light enhanced oxidative phosphorylation by promoting fatty acid oxidation. Keratinocytes are the primary constituents of sunlight‐exposed epidermis.
Manuel Alejandro Herrera +4 more
wiley +1 more source
On the Robustness of the Principal Volatility Components [PDF]
SSRN Electronic Journal, 2018 Abstract In this paper, we analyse the recent principal volatility components analysis procedure. The procedure overcomes several difficulties in modelling and forecasting the conditional covariance matrix in large dimensions arising from the curse of dimensionality. We show that outliers have a devastating effect on the construction of the principal
Carlos Trucíos +2 more
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