Search results for "PCA"
showing 10 items of 130 documents
Multiple Estrogen Function in Human Prostate Cancer Cells
1996
Prostate health index (PHI) as a reliable biomarker for prostate cancer: a systematic review and meta-analysis.
2022
Abstract Objectives Prostate cancer (PCa) represents the second most common solid cancer in men worldwide. In the last decades, the prostate health index (PHI) emerged as a reliable biomarker for detecting PCa and differentiating between non-aggressive and aggressive forms. However, before introducing it in clinical practice, more evidence is required. Thus, we performed a systematic review and meta-analysis for assessing the diagnostic performance of PHI for PCa and for detecting clinically significant PCa (csPCa). Methods Relevant publications were identified by a systematic literature search on PubMed and Web of Science from inception to January 11, 2022. Results Sixty studies, including…
Choline PET/CT Features to Predict Survival Outcome in High Risk Prostate Cancer Restaging: A Preliminary Machine-Learning Radiomics Study
2020
Background Radiomic features are increasingly utilized to evaluate tumor heterogeneity in PET imaging but to date its role has not been investigated for Cho-PET in prostate cancer. The potential application of radiomics features analysis using a machine-learning radiomics algorithm was evaluated to select 18F-Cho PET/CT imaging features to predict disease progression in PCa. Methods We retrospectively analyzed high-risk PCa patients who underwent restaging 18F-Cho PET/CT from November 2013 to May 2018. 18F-Cho PET/CT studies and related structures containing volumetric segmentations were imported in the "CGITA" toolbox to extract imaging features from each lesion. A Machine-learning model h…
La calidad y el valor percibido en el transporte de mercancías en España y su importancia en la segmentación de clientes
2015
En el estudio académico de las actividades logísticas y específicamente del transporte de mercancías, se ha señalado la influencia de la calidad del servicio en la generación y percepción de valor, así como la importancia de estos dos constructos en el proceso de evaluación del servicio en este entorno particular. En este trabajo se pretende identificar y caracterizar segmentos de empresas que prestan servicios de gestión del transporte internacional de mercancías (transitarias), con base en el valor que perciben del servicio recibido de sus principales proveedores de transporte de mercancías. A través de la realización de un análisis factorial exploratorio sobre una muestra de 205 empresas…
Essential oil variation within and among natural populations of Lavandula latifolia and its relation to their ecological areas
2007
Essential oil yield and composition in seven natural populations of Lavandula latifolia from the eastern Iberian Peninsula were determined by GC/MS. Twenty-eight constituents were identified, accounting for 92.0e95.4% of the total oils. These oils were dominated by the monoterpene fraction and three of them (linalool, cineole and camphor) constituted 79.5e86.9% of the oil from flowers. Essential oil yield in leaves and flowers varied among and within populations, but hierarchic analyses of variance showed that the proportion of variation attributable to individuals was significantly higher than that attributable to population differences. Principal component and cluster analyses allowed thr…
Volatile constituents of the aerial parts of Pulicaria sicula (L.) Moris growing wild in Sicily: Chemotaxonomic volatile markers of the genus Pulicar…
2015
Abstract The chemical composition of the essential oil isolated from the aerial parts of Pulicaria sicula (L.) Moris was characterized by GC-FID and GC/MS analyses. The oil was particularly rich in oxygenated terpenoids. Among the oxygenated monoterpenes (content of 44.5%), the most abundant were borneol (23.7%), bornyl acetate (6.5%), and isothymol isobutyrate (6.2%). Caryophyllene oxide (10.2%), caryophylladienol I (4.3%), and caryophylla-3,8(13)-dien-5β-ol (4.4%) were identified as the main constituents among the oxygenated sesquiterpenes. Furthermore, a complete literature review on the composition of the essential oils of all the Pulicaria taxa studied so far was performed and a princi…
The Essential Oil Compositions of Three Teucrium Taxa Growing Wild in Sicily: HCA and PCA Analyses
2021
The chemical composition and the qualitative and quantitative variability of the essential oils of three taxa belonging to the Teucrium genus were studied. The investigated taxa, that grow wild in Sicily, were Teucrium flavum L. (section Chamaedrys (Mill.) Scheb.), Teucrium montanum and Teucrium capitatum L. of section Polium (Mill.) Scheb. Essential oils were extracted by hydrodistillation and analyzed by GC-MS. In total, 74 compounds were identified. Sesquiterpene hydrocarbons were found to be the main group for T. flavum (48.3%). T. capitatum consisted essentially of monoterpene hydrocarbons (72.7%), with &alpha
Changes in the flow and quality of water in the dam reservoir of the Mała Panew catchment (South Poland) characterized by multidimensional data analys…
2023
Multidimensional exploratory techniques, such as the Principal Component Analysis (PCA), have been used to analyze long-term changes in the fl ow regime and quality of water of the lowland dam reservoir Turawa (south-west Poland) in the catchment of the Mała Panew river (a tributary of the Odra). The paper proves that during the period of 1998–2016 the Turawa reservoir was equalizing the river’s water fl ow. Moreover, various physicochemical water quality indicators were analyzed at three measurement points (at the tributary’s mouth into the reservoir, in the reservoir itself and at the outfl ow from the reservoir). The water quality assessment was performed by analyzing physicochemical ind…
On Spatio-Temporal Saliency Detection in Videos using Multilinear PCA
2016
International audience; Visual saliency is an attention mechanism which helps to focus on regions of interest instead of processing the whole image or video data. Detecting salient objects in still images has been widely addressed in literature with several formulations and methods. However, visual saliency detection in videos has attracted little attention, although motion information is an important aspect of visual perception. A common approach for obtaining a spatio-temporal saliency map is to combine a static saliency map and a dynamic saliency map. In this paper, we extend a recent saliency detection approach based on principal component analysis (PCA) which have shwon good results wh…
A Multivariate Analysis on Non-nucleoside HIV-1 Reverse Transcriptase Inhibitors and Resistance Induced by Mutation
2003
This paper describes the use of multivariate statistical procedure PCA as a tool to explore the inhibitory activity of classes of NNRTIs against HIV-1 viruses (wild type and more frequent mutants, Y181C, V106A, K103N, L100I) and against RT enzyme. The analysis of correlations between biological activity and molecular descriptors or similarity indexes allowed a reliable classification of the fifty five derivatives considered in this study. The best results were obtained in the case of L100I and K103N mutants for which the higher number of assignments was found when the principal components derived from the descriptors were used. On this basis this statistical approach is proposed as a reliab…