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Principal components analysis

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https://www.readbyqxmd.com/read/28343079/population-model-of-bladder-motion-and-deformation-based-on-dominant-eigenmodes-and-mixed-effects-models-in-prostate-cancer-radiotherapy
#1
Richard Rios, Renaud De Crevoisier, Juan D Ospina, Frederic Commandeur, Caroline Lafond, Antoine Simon, Pascal Haigron, Jairo Espinosa, Oscar Acosta
In radiotherapy for prostate cancer irradiation of neighboring organs at risk may lead to undesirable side-effects. Given this setting, the bladder presents the largest inter-fraction shape variations hampering the computation of the actual delivered dose vs. planned dose. This paper proposes a population model, based on longitudinal data, able to estimate the probability of bladder presence during treatment, using only the planning computed tomography (CT) scan as input information. As in previously-proposed principal component analysis (PCA) population-based models, we have used the data to obtain the dominant eigenmodes that describe bladder geometric variations between fractions...
March 8, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28343041/characterization-of-regional-cold-hydrothermal-inflows-enriched-in-arsenic-and-associated-trace-elements-in-the-southern-part-of-the-duero-basin-spain-by-multivariate-statistical-analysis
#2
Elena Giménez-Forcada, Marisol Vega-Alegre, Susana Timón-Sánchez
Naturally occurring arsenic in groundwater exceeding the limit for potability has been reported along the southern edge of the Cenozoic Duero Basin (CDB) near its contact with the Spanish Central System (SCS). In this area, spatial variability of arsenic is high, peaking at 241μg/L. Forty-seven percent of samples collected contained arsenic above the maximum allowable concentration for drinking water (10μg/L). Correlations of As with other hydrochemical variables were investigated using multivariate statistical analysis (Hierarchical Cluster Analysis, HCA and Principal Component Analysis, PCA)...
March 23, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28342605/relationship-between-mozzarella-yield-and-milk-composition-processing-factors-and-recovery-of-whey-constituents
#3
D C Sales, A H N Rangel, S A Urbano, Alfredo R Freitas, Humberto Tonhati, L P Novaes, M I B Pereira, L H F Borba
Our aim was to identify the relationship between mozzarella cheese yield and buffalo milk composition, processing factors, and recovery of whey constituents. A production of 30 batches of mozzarella cheese at a dairy industry in northeast Brazil (Rio Grande do Norte) was monitored between March and November, 2015. Mozzarella yield and 32 other variables were observed for each batch, and divided into 3 groups: milk composition variables (12); variables involved in the cheesemaking process (14); and variables for recovery of whey constituents (6)...
March 22, 2017: Journal of Dairy Science
https://www.readbyqxmd.com/read/28340385/experimental-study-of-polyethylene-pyrolysis-and-combustion-over-hzsm-5-husy-and-mcm-41
#4
Que Huang, Changcheng Liu, Ruichao Wei, Jian Wang
The effects of temperatures, catalysts, and catalyst contents on polyethylene (PE) pyrolysis were investigated by using single-photon ionization time-of-flight mass spectrometry (SPI-TOFMS). The mass spectra of pyrolyzed PE and PE/catalysts from 300°C to 800°C illustrate that the pyrolysis reactions were apparently promoted and varied by introducing HZSM-5, HUSY, and MCM-41. As microporous catalysts, HZSM-5 and HUSY were found to accelerate the BTX formation at 400°C, which could not be observed for pure PE until 800°C...
March 14, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28340178/morphometric-covariation-between-palatal-shape-and-skeletal-pattern-in-class-ii-growing-subjects
#5
Valeria Paoloni, Roberta Lione, Francesca Farisco, Demetrios J Halazonetis, Lorenzo Franchi, Paola Cozza
Objectives: To evaluate the patterns of covariation between palatal and craniofacial morphology in Class II subjects in the early mixed dentition by means of geometric morphometrics. Methods: A cross-sectional sample of 85 Class II subjects (44 females, 41 males; mean age 8.7 years ± 0.8) was collected retrospectively according to the following inclusion criteria: European ancestry (white), Class II skeletal relationship, Class II division 1 dental relationship, early mixed dentition, and prepubertal skeletal maturation...
March 14, 2017: European Journal of Orthodontics
https://www.readbyqxmd.com/read/28339829/perceived-office-environments-and-occupational-physical-activity-in-office-based-workers
#6
A Sawyer, L Smith, M Ucci, R Jones, A Marmot, A Fisher
Background: Individuals in office-based occupations have low levels of physical activity but there is little research into the socio-ecological correlates of workplace activity. Aims: To identify factors contributing to office-based workers' perceptions of the office environment and explore cross-sectional relationships between these factors and occupational physical activity. Methods: Participants in the Active Buildings study reported perceptions of their office environment using the Movement at Work Survey...
March 1, 2017: Occupational Medicine
https://www.readbyqxmd.com/read/28339782/the-adolescent-hiv-disclosure-cognition-and-affect-scale-preliminary-reliability-and-validity
#7
Michael Evangeli
Globally, there are 2 million HIV-positive 10-19-year-olds. One challenge for this population is sharing their HIV status with others (onward HIV disclosure). There are no multi-item, multidimensional scales of HIV disclosure cognitions and affect for young people living with HIV. An 18-item measure of HIV disclosure cognition and affect was developed, administered to 65 adolescents living with HIV (aged 12-16 years). Data were explored using principal component analysis and preliminary construct and criterion validity assessed...
February 26, 2017: Journal of Pediatric Psychology
https://www.readbyqxmd.com/read/28338798/genetic-dissection-of-metabolite-variation-in-arabidopsis-seeds-evidence-for-mqtl-hotspots-and-a-master-regulatory-locus-of-seed-metabolism
#8
Dominic Knoch, David Riewe, Rhonda Christiane Meyer, Anastassia Boudichevskaia, Renate Schmidt, Thomas Altmann
To gain insight into genetic factors controlling seed metabolic composition and its relationship to major seed properties, an Arabidopsis recombinant inbred line (RIL) population, derived from accessions Col-0 and C24, was studied using an MS-based metabolic profiling approach. Relative intensities of 311 polar primary metabolites were used to identify associated genomic loci and to elucidate their interactions by quantitative trait locus (QTL) mapping. A total of 786 metabolic QTLs (mQTLs) were unequally distributed across the genome, forming several hotspots...
March 6, 2017: Journal of Experimental Botany
https://www.readbyqxmd.com/read/28338794/genome-wide-association-study-unravels-the-genetic-control-of-the-apple-volatilome-and-its-interplay-with-fruit-texture
#9
Brian Farneti, Mario Di Guardo, Iuliia Khomenko, Luca Cappellin, Franco Biasioli, Riccardo Velasco, Fabrizio Costa
Fruit quality represents a fundamental factor guiding consumers' preferences. Among apple quality traits, volatile organic compounds and texture features play a major role. Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS), coupled with an artificial chewing device, was used to profile the entire apple volatilome of 162 apple accessions, while the fruit texture was dissected with a TAXT-AED texture analyzer. The array of volatile compounds was classed into seven major groups and used in a genome-wide association analysis carried out with 9142 single nucleotide polymorphisms (SNPs)...
February 24, 2017: Journal of Experimental Botany
https://www.readbyqxmd.com/read/28338728/characterising-root-trait-variability-in-chickpea-cicer-arietinum-l-germplasm
#10
Yinglong Chen, Michel Edmond Ghanem, Kadambot Hm Siddique
Chickpea (Cicer arietinum L.) is an important grain legume crop but its sustainable production is challenged by predicted climate changes, which are likely to increase production limitations and uncertainty in yields. Characterising the variability in root architectural traits in a core collection of chickpea germplasm will provide the basis for breeding new germplasm with suitable root traits for the efficient acquisition of soil resources and adaptation to drought and other abiotic stresses. This study used a semi-hydroponic phenotyping system for assessing root trait variability across 270 chickpea genotypes...
October 6, 2016: Journal of Experimental Botany
https://www.readbyqxmd.com/read/28338641/nerolidol-and-farnesol-inhibit-some-cytochrome-p450-activities-but-did-not-affect-other-xenobiotic-metabolizing-enzymes-in-rat-and-human-hepatic-subcellular-fractions
#11
Alena Špičáková, Barbora Szotáková, Diana Dimunová, Zuzana Myslivečková, Vladimír Kubíček, Martin Ambrož, Kateřina Lněničková, Kristýna Krasulová, Pavel Anzenbacher, Lenka Skálová
Sesquiterpenes, 15-carbon compounds formed from three isoprenoid units, are the main components of plant essential oils. Sesquiterpenes occur in human food, but they are principally taken as components of many folk medicines and dietary supplements. The aim of our study was to test and compare the potential inhibitory effect of acyclic sesquiterpenes, trans-nerolidol, cis-nerolidol and farnesol, on the activities of the main xenobiotic-metabolizing enzymes in rat and human liver in vitro. Rat and human subcellular fractions, relatively specific substrates, corresponding coenzymes and HPLC, spectrophotometric or spectrofluorometric analysis of product formation were used...
March 24, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28338499/development-of-the-irritable-bowel-syndrome-cognitive-affective-scale-a-brief-self-report-measure-for-clinical-and-research-settings
#12
Sarah Ballou, Laurie Keefer
OBJECTIVES: Measures of cognitive-affective processes believed to underlie Irritable Bowel Syndrome (IBS) symptom expression are used widely in both clinical and research settings. When combined, these measures can be time-consuming and it is not clear whether they evaluate distinct or overlapping constructs. With this study, we seek to identify the most critical cognitive-affective components contributing toward the expression of IBS and to identify which items in these constructs might be streamlined into a single, brief self-report measure...
March 23, 2017: European Journal of Gastroenterology & Hepatology
https://www.readbyqxmd.com/read/28338236/hsa-mir-3199-2-and-hsa-mir-1293-as-novel-prognostic-biomarkers-of-papillary-renal-cell-carcinoma-by-cox-ratio-risk-regression-model-screening
#13
Wen Luo, Lei Wang, Mao-Hua Luo, Yu-Zhu Huang, Hua Yang, Yu Zhou, Hong-Tao Jia, Xiu-Xin Wang
Papillary renal cell carcinoma(PRCC) is the second most common and aggressive renal cell carcinoma. Identification of novel microRNA biomarkers could be beneficial for the diagnosis and prognosis of PRCCpatients.We aimed to screen differentially expressed miRNAs that can act as prognostic factors and to predict the survival of PRCC patients. High-throughput data of miRNAs of 274 PRCC samples were downloaded from TCGA(The Cancer Genome Atlas) dataset and interested miRNAs were identified. Hierarchical clustering and principal component analysis (PCA) were performed on these miRNAs...
March 24, 2017: Journal of Cellular Biochemistry
https://www.readbyqxmd.com/read/28337740/proteome-comparison-for-discrimination-between-honeydew-and-floral-honeys-from-botanical-specie-mimosa-scabrella-bentham-by-principal-component-analysis
#14
Mônia Stremel Azevedo, Pedro Alexandre Valentim-Neto, Siluana Katia Tischer Seraglio, Cynthia Fernandes Pinto da Luz, Ana Carolina Maisonnave Arisi, Ana Carolina Oliveira Costa
BACKGROUND: Due to increasing valuation and appreciation of honeydew honey in many European countries and also to existing contamination among different kinds of honeys, the authentication is an important aspect of quality control and its regard with the origin guarantee in terms of source, honeydew or floral, needs to be determined. Furthermore, belonging to the minority composition of the honey, beyond of the importance of its physiological effects, proteins can differ according to these sources...
March 23, 2017: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/28337429/investigating-cardiac-motion-patterns-using-synthetic-high-resolution-3d-cardiovascular-magnetic-resonance-images-and-statistical-shape-analysis
#15
Benedetta Biffi, Jan L Bruse, Maria A Zuluaga, Hopewell N Ntsinjana, Andrew M Taylor, Silvia Schievano
Diagnosis of ventricular dysfunction in congenital heart disease is more and more based on medical imaging, which allows investigation of abnormal cardiac morphology and correlated abnormal function. Although analysis of 2D images represents the clinical standard, novel tools performing automatic processing of 3D images are becoming available, providing more detailed and comprehensive information than simple 2D morphometry. Among these, statistical shape analysis (SSA) allows a consistent and quantitative description of a population of complex shapes, as a way to detect novel biomarkers, ultimately improving diagnosis and pathology understanding...
2017: Frontiers in Pediatrics
https://www.readbyqxmd.com/read/28336916/evaluation-of-the-effects-of-irrigation-and-fertilization-on-tomato-fruit-yield-and-quality-a-principal-component-analysis
#16
Xiukang Wang, Yingying Xing
Irrigation and fertilization are key practices for improving the fruit quality and yield of vegetables grown in greenhouses. We carried out an experiment in a solar greenhouse spanning three consecutive growing seasons to evaluate the effects of irrigation and fertilization on the fruit yield and quality, water use efficiency (WUE) and fertilizer partial factor productivity (PFP) of tomatoes. Interactions between irrigation and fertilization treatments and individual factors of irrigation and fertilization significantly (p < 0...
March 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28336451/effect-of-soybean-phosphatidylcholine-on-lipid-profile-of-bovine-oocytes-matured-in-vitro
#17
Caroline P Pitangui-Molina, Alessandra A Vireque, Alessandra Tata, Katia Roberta A Belaz, Vanessa G Santos, Christina R Ferreira, Marcos N Eberlin, Marcos Felipe S Sá, Rui A Ferriani, Ana Carolina J S Rosa-E-Silva
The phospholipid (PL) composition of embryo and oocyte membranes affects thermal phase behavior and several physicochemical properties such as fluidity and permeability. The characterization of PL profiles and the development of suitable in vitro maturation (IVM) protocols, that are able to modify membrane's composition, may result in significant improvements in oocyte developmental potential and cryotolerance. Using soybean phosphatidylcholine (PC) as a model supplement, we evaluated the effect of PL supplementation during IVM on bovine cumulus-oocyte-complex (COC)...
March 20, 2017: Chemistry and Physics of Lipids
https://www.readbyqxmd.com/read/28336417/demonstrating-the-value-and-importance-of-combining-dna-barcodes-and-discriminant-morphological-characters-for-polystome-taxonomy-platyhelminthes-monogenea
#18
Laurent Héritier, Olivier Verneau, Kevin G Smith, Carina Coetzer, Louis H Du Preez
Polystomes are monogenean parasites that infest mainly semi aquatic vertebrates, such as amphibians and chelonians. Owing to the lack of discriminative morphological characters and because polystomes are considered to be strictly host- and site-specific, host identity is often used as an additional character for parasite identification. Recent genetic studies, however, show that polystomes infecting freshwater turtles in outdoor turtle enclosures and natural environments, are not strictly host-specific. Therefore, we proposed a new procedure for turtle polystome taxonomy based on the combination of Cytochrome c Oxydase I sequences and two discriminant morphological characters, namely the number of genital spines and the testis shape...
March 20, 2017: Parasitology International
https://www.readbyqxmd.com/read/28335962/combining-anova-pca-with-pochemon-to-analyse-micro-organism-development-in-a-polymicrobial-environment
#19
Brigitte P Geurts, Anne H Neerincx, Samuel Bertrand, Manja A A P Leemans, Geert J Postma, Jean-Luc Wolfender, Simona M Cristescu, Lutgarde M C Buydens, Jeroen J Jansen
Revealing the biochemistry associated to micro-organismal interspecies interactions is highly relevant for many purposes. Each pathogen has a characteristic metabolic fingerprint that allows identification based on their unique multivariate biochemistry. When pathogen species come into mutual contact, their co-culture will display a chemistry that may be attributed both to mixing of the characteristic chemistries of the mono-cultures and to competition between the pathogens. Therefore, investigating pathogen development in a polymicrobial environment requires dedicated chemometric methods to untangle and focus upon these sources of variation...
April 22, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28335521/gene-transformation-induced-changes-in-chemical-functional-group-features-and-molecular-structure-conformation-in-alfalfa-plants-co-expressing-lc-bhlh-and-c1-myb-transcriptive-flavanoid-regulatory-genes-effects-of-single-gene-and-two-gene-insertion
#20
Ravindra G Heendeniya, Peiqiang Yu
Alfalfa (Medicago sativa L.) genotypes transformed with Lc-bHLH and Lc transcription genes were developed with the intention of stimulating proanthocyanidin synthesis in the aerial parts of the plant. To our knowledge, there are no studies on the effect of single-gene and two-gene transformation on chemical functional groups and molecular structure changes in these plants. The objective of this study was to use advanced molecular spectroscopy with multivariate chemometrics to determine chemical functional group intensity and molecular structure changes in alfalfa plants when co-expressing Lc-bHLH and C1-MYB transcriptive flavanoid regulatory genes in comparison with non-transgenic (NT) and AC Grazeland (ACGL) genotypes...
March 20, 2017: International Journal of Molecular Sciences
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