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Principal components analysis

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https://www.readbyqxmd.com/read/28637334/new-predictor-of-aortic-enlargement-in-uncomplicated-type-b-aortic-dissection-based-on-elliptic-fourier-analysis
#1
Hiroshi Sato, Toshiro Ito, Yosuke Kuroda, Hiroki Uchiyama, Toshitaka Watanabe, Naomi Yasuda, Junji Nakazawa, Ryo Harada, Nobuyoshi Kawaharada
OBJECTIVES: This study aimed to re-examine the conventional predictive factors for dissected aortic enlargement, such as the aortic and false lumen diameter and to consider whether the morphological elements of the dissected aorta could be predictors by quantifying the 'shape' of the true lumen based on elliptic Fourier analysis. METHODS: A total of 80 patients with uncomplicated type B aortic dissection were included. The patients were divided into 'Enlargement group' and 'No Change group...
May 22, 2017: European Journal of Cardio-thoracic Surgery
https://www.readbyqxmd.com/read/28637135/cross-cultural-validity-of-the-abiloco-questionnaire-for-individuals-with-stroke-based-on-rasch-analysis
#2
Patrick Roberto Avelino, Lívia Castro Magalhães, Iza Faria-Fortini, Marluce Lopes Basílio, Kênia Kiefer Parreiras Menezes, Luci Fuscaldi Teixeira-Salmela
PURPOSE: The purpose of this study was to evaluate the cross-cultural validity of the Brazilian version of the ABILOCO questionnaire for stroke subjects. MATERIALS AND METHODS: Cross-cultural adaptation of the original English version of the ABILOCO to the Brazilian-Portuguese language followed standardized procedures. The adapted version was administered to 136 stroke subjects and its measurement properties were assessed using Rash analysis. Cross-cultural validity was based on cultural invariance analyses...
February 10, 2017: Disability and Rehabilitation
https://www.readbyqxmd.com/read/28636649/factors-associated-with-successful-transition-among-children-with-disabilities-in-eight-european-countries
#3
John Ravenscroft, Kerri Wazny, John M Davis
INTRODUCTION: This research paper aims to assess factors reported by parents associated with the successful transition of children with complex additional support requirements that have undergone a transition between school environments from 8 European Union member states. METHODS: Quantitative data were collected from 306 parents within education systems from 8 EU member states (Bulgaria, Cyprus, Greece, Ireland, the Netherlands, Romania, Spain and the UK). The data were derived from an online questionnaire and consisted of 41 questions...
2017: PloS One
https://www.readbyqxmd.com/read/28636572/mood-symptoms-in-stabilized-patients-with-schizophrenia-a-bipolar-type-with-predominant-psychotic-features
#4
Konstantinos N Fountoulakis, Dina Popovic, Mariela Mosheva, Melina Siamouli, Katerina Moutou, Xenia Gonda
BACKGROUND: Schizophrenia (SZ) and bipolar disorder (BD) are traditionally distinguished on the basis of progressive deterioration and long-term outcome, but a more dimensional approach is warranted. There are limited data on the occurrence of manic symptoms in patients with schizophrenia. The aim of the current study was to search for patterns in the clinical symptomatology, which may suggest the presence of one or several mood disorders under the label of schizophrenia. SUBJECTS AND METHODS: Hundred-seventy-five patients diagnosed with schizophrenia according to DSM-5 were included in the study...
June 2017: Psychiatria Danubina
https://www.readbyqxmd.com/read/28636183/ordination-with-any-dissimilarity-measure-a-weighted-euclidean-solution
#5
Michael Greenacre
The classical approach to ordination is to use variants of the Euclidean distance to measure differences between samples (e.g. sites in a community study) based on their observation vectors (e.g. abundance counts for a set of species). Examples are: Euclidean distance on standardized or log-transformed data, on which principal component analysis and redundancy analysis are based; chi-square distance, on which (canonical) correspondence analysis is based; and Hellinger distance, using square roots of relative values in each multivariate vector...
June 21, 2017: Ecology
https://www.readbyqxmd.com/read/28636053/evidence-of-bad-recycling-practices-bfrs-in-children-s-toys-and-food-contact-articles
#6
A Guzzonato, F Puype, S J Harrad
Brominated flame retardants (BFRs) have been used intentionally in a wide range of plastics, but are now found in an even wider range of such materials (including children's toys and food contact articles) as a result of recycling practices that mix BFR-containing waste plastics with "virgin" materials. In this study Br was quantified in toy and food contact samples on the assumption that its concentration can be used as a metric for BFR contamination. Subsequently, compound specific determination of BFRs was performed to evaluate the validity of the aforementioned assumption, crucial to render rapid, inexpensive, in situ Br determination in non-laboratory environments (such as waste handling facilities) a viable option for sorting wastes according to their BFR content...
June 21, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28635552/temporal-variation-of-fine-and-coarse-particulate-matter-sources-in-jeddah-saudi-arabia
#7
Chris C Lim, George D Thurston, Magdy Shamy, Mansour Alghamdi, Mamdouh Khoder, Abdullah M Mohorjy, Abdulrahman K Alkhalaf, Jason Brocato, Lung Chi Chen, Max Costa
This study provides the first comprehensive analysis of the seasonal variations and weekday/weekend differences in fine (PM2.5) and coarse (PM2.5-10) particulate matter mass concentrations, elemental constituents, and potential source origins in Jeddah, Saudi Arabia. Air quality samples were collected over one year, from June 2011 to May 2012 at a frequency of three times per week, and analyzed. The average mass concentrations of PM2.5 (21.9 μg/m(3)) and PM10 (107.8 μg/m(3)) during the sampling period exceeded the recommended annual average levels by the World Health Organization (WHO) for PM2...
June 21, 2017: Journal of the Air & Waste Management Association
https://www.readbyqxmd.com/read/28635499/hearing-aid-fine-tuning-based-on-dutch-descriptions
#8
Thijs Thielemans, Donné Pans, Michelene Chenault, Lucien Anteunis
OBJECTIVE: The aim of this study was to derive an independent fitting assistant based on expert consensus. Two questions were asked: (1) what (Dutch) terms do hearing impaired listeners use nowadays to describe their specific hearing aid fitting problems? (2) What is the expert consensus on how to resolve these complaints by adjusting hearing aid parameters? DESIGN: Hearing aid dispensers provided descriptors that impaired listeners use to describe their reactions to specific hearing aid fitting problems...
February 20, 2017: International Journal of Audiology
https://www.readbyqxmd.com/read/28635416/arsenic-and-fluoride-co-contamination-in-shallow-aquifers-from-agricultural-suburbs-and-an-industrial-area-of-punjab-pakistan-spatial-trends-sources-and-human-health-implications
#9
Abida Farooqi, Jawairia Sultana, Noshin Masood
Release of arsenic (As) and fluoride (F(-)) species into groundwater is a serious health concern around the world. The present study was the first systematic baseline study conducted in Rahim Yar Khan district, Punjab, focusing on As and F(-) contamination in groundwater. A total of 51 representative groundwater samples comprising of 44 samples from agricultural suburbs and 7 from an industrial base were analysed. Statistical parameters, principal component analysis-multiple linear regression (PCA-MLR) and health risk assessment model were used to investigate the hydro geochemistry, spatial patterns, interrelation, source contribution and associated health risks of high As and F(-) in groundwater of the study area...
January 1, 2017: Toxicology and Industrial Health
https://www.readbyqxmd.com/read/28635163/early-pregnancy-body-mass-index-modifies-the-association-of-pre-pregnancy-dietary-patterns-with-serum-polyunsaturated-fatty-acid-concentrations-throughout-pregnancy-in-brazilian-women
#10
Camila Benaim, Ana Amélia Freitas-Vilela, Thatiana de Jesus Pereira Pinto, Jaqueline Lepsch, Dayana Rodrigues Farias, Juliana Dos Santos Vaz, Tatiana El-Bacha, Gilberto Kac
Dietary patterns (DPs) have been described as an important factor that may influence polyunsaturated fatty acid (PUFA) concentrations and body mass index (BMI) during pregnancy. We aim to evaluate the association between pre-pregnancy DPs and serum PUFA percentages throughout pregnancy considering early pregnancy BMI as a possible effect modifier. A prospective cohort of 154 pregnant women was followed (5th-13th, 20th-26th, and 30th-36th gestational weeks). Serum PUFA concentrations (total n-3 and total n-6, eicosapentaenoic + docosahexaenoic acids) were measured in each trimester and expressed as percentages...
June 21, 2017: Maternal & Child Nutrition
https://www.readbyqxmd.com/read/28634797/distribution-transfer-and-health-risks-of-polycyclic-aromatic-hydrocarbons-pahs-in-soil-wheat-systems-of-henan-province-a-typical-agriculture-province-of-china
#11
Jinglan Feng, Xiaoying Li, Jiahui Zhao, Jianhui Sun
In order to investigate the distribution, transfer, and human health risks of polycyclic aromatic hydrocarbons (PAHs) in the soil-wheat systems, soil samples from 20 farmlands and corresponding wheat tissues were collected from selected regions of Henan Province in June 2013 and were analyzed to estimate the concentration of PAHs. The total concentrations of 15 PAHs (∑15 PAHs) in soils from Henan Province varied from 6.91 to 72.4 ng/g. Moreover, two-ring to three-ring PAHs (1.59-29.1 ng/g) were the major species in soils, occupying 56...
June 20, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28633707/qualitative-analysis-of-biological-tuberculosis-samples-by-an-electronic-nose-based-artificial-neural-network
#12
E I Mohamed, M A Mohamed, M H Moustafa, S M Abdel-Mageed, A M Moro, A I Baess, S M El-Kholy
OBJECTIVE: To apply an e-nose system for monitoring headspace volatiles in biological samples from Egyptian patients with active pulmonary tuberculosis (TB) and healthy controls (HCs) and compare them with standard sputum analysis. DESIGN: The study population comprised 260 (140 males, 120 females) newly diagnosed TB patients and 240 (120 males, 120 females) HCs matched by age and socio-economic level admitted to hospitals specialising in chest diseases in Alexandria, Behera, Giza and Damietta Governorates, Egypt...
July 1, 2017: International Journal of Tuberculosis and Lung Disease
https://www.readbyqxmd.com/read/28633602/functional-principal-component-analysis-of-glomerular-filtration-rate-curves-after-kidney-transplant
#13
Jianghu J Dong, Liangliang Wang, Jagbir Gill, Jiguo Cao
This article is motivated by some longitudinal clinical data of kidney transplant recipients, where kidney function progression is recorded as the estimated glomerular filtration rates at multiple time points post kidney transplantation. We propose to use the functional principal component analysis method to explore the major source of variations of glomerular filtration rate curves. We find that the estimated functional principal component scores can be used to cluster glomerular filtration rate curves. Ordering functional principal component scores can detect abnormal glomerular filtration rate curves...
January 1, 2017: Statistical Methods in Medical Research
https://www.readbyqxmd.com/read/28633391/kmerpyramid-an-interactive-visualization-tool-for-nucleobase-and-k-mer-frequencies
#14
Jochen Kruppa, Erhard van der Vries, Wendy K Jo, Alexander Postel, Paul Becher, Albert Osterhaus, Klaus Jung
Summary: Bioinformatics methods often incorporate the frequency distribution of nulecobases or k -mers in DNA or RNA sequences, for example as part of metagenomic or phylogenetic analysis. Because the frequency matrix with sequences in the rows and nucleobases in the columns is multi-dimensional it is hard to visualize. We present the R-package 'kmerPyramid' that allows to display each sequence, based on its nucleobase or k -mer distribution projected to the space of principal components, as a point within a 3-dimensional, interactive pyramid...
June 15, 2017: Bioinformatics
https://www.readbyqxmd.com/read/28633306/multivariate-phylogenetic-comparative-methods-evaluations-comparisons-and-recommendations
#15
Dean C Adams, Michael L Collyer
Recent years have seen increased interest in phylogenetic comparative analyses of multivariate datasets, but to date the varied proposed approaches have not been extensively examined. Here we review the mathematical properties required of any multivariate method, and specifically evaluate existing multivariate phylogenetic comparative methods in this context. Phylogenetic comparative methods based on the full multivariate likelihood are robust to levels of covariation among trait dimensions and are insensitive to the orientation of the dataset, but display increasing model misspecification as the number of trait dimensions increases...
June 13, 2017: Systematic Biology
https://www.readbyqxmd.com/read/28633303/cognitive-trajectories-in-prediabetes-and-diabetes-a-population-based-cohort-study
#16
Anna Marseglia, Anna K Dahl Aslan, Laura Fratiglioni, Giola Santoni, Nancy L Pedersen, Weili Xu
Background: Diabetes has been linked to dementia risk; however, the cognitive trajectories in older adults with diabetes remain unclear. We aimed to investigate the effect of prediabetes and diabetes on cognitive trajectories among cognitively intact older adults in a long-term follow-up study. Methods: Within the Swedish Adoption/Twin Study of Aging, 793 cognitively intact older adults aged ≥50 were identified at baseline and followed for up to 23 years. Based on standardized scores from 11 cognitive tests, administered at baseline and up to seven follow-ups, four cognitive domains (verbal abilities, spatial/fluid, memory, perceptual speed) were identified by principal-component analysis...
June 13, 2017: Journals of Gerontology. Series A, Biological Sciences and Medical Sciences
https://www.readbyqxmd.com/read/28633145/urinary-volatile-organic-compounds-as-potential-biomarkers-in-idiopathic-membranous-nephropathy
#17
Mingao Wang, Rujuan Xie, Xibei Jia, Ruichan Liu
OBJECTIVE: To detect urinary volatile organic compounds (VOCs) in patients with idiopathic membranous nephropathy (iMN) and normal controls, and whether or not the urinary VOCs can act as biomarkers for diagnosis of iMN independent of renal biopsy. MATERIALS AND METHODS: Gas chromatography/mass spectrometry (GC/MS) was used to assess the urine collected from 63 iMN patients and 15 normal controls. The statistical methods of principal component analysis (PCA) and partial least squares discriminant analysis (PLSDA) were performed to process the final data in CDF format which were converted from GC/MS data...
June 19, 2017: Medical Principles and Practice: International Journal of the Kuwait University, Health Science Centre
https://www.readbyqxmd.com/read/28632431/psychometric-testing-of-a-swedish-version-of-the-apathy-evaluation-scale
#18
Maurits Johansson, Per Johansson, Erik Stomrud, Peter Hagell, Oskar Hansson
BACKGROUND: Apathy, a prevalent and clinically relevant symptom in neurodegenerative disease, is often evaluated by the instrument Apathy Evaluation Scale (AES). However, this instrument has not been translated into Swedish, halting clinical and research efforts. Furthermore, previous studies lack analyses of some basic properties, such as the legitimacy of a total score, or have analysed dimensionality by questionable methods. AIM: To translate and psychometrically evaluate a Swedish version of the AES...
June 20, 2017: Nordic Journal of Psychiatry
https://www.readbyqxmd.com/read/28631205/chemical-tongues-and-noses-based-upon-conjugated-polymers
#19
REVIEW
Jan Freudenberg, Felix Hinkel, Daniel Jänsch, Uwe H F Bunz
We report the uses of conjugated polymers in multisensory applications and in chemical and optoelectronic tongues. We look at the potential of single polymers to discriminate multiple analytes and into small libraries of conjugated polymers that represent sensors. These small libraries combine several barely selective, promiscuous sensor elements and react with the analytes in a fairly non-selective fashion by change of color, emission wavelength, or emission intensity. In such optoelectronic noses and tongues, response of a single element is not specific or particularly useful at all, but the response pattern after the combination of several sensor elements is often specific for an analyte and allows discrimination and identification without any problem...
August 2017: Topics in Current Chemistry (Journal)
https://www.readbyqxmd.com/read/28630939/retrospective-surveillance-of-wastewater-to-examine-seasonal-dynamics-of-enterovirus-infections
#20
Nichole E Brinkman, G Shay Fout, Scott P Keely
Enteroviruses are RNA viruses that are responsible for both mild gastroenteritis and mild respiratory illnesses as well as debilitating diseases such as meningitis and myocarditis. The disease burden of enteroviruses in the United States is difficult to assess because most infections are not recorded. Since infected individuals shed enterovirus in feces and urine, surveillance of municipal wastewater can reveal the diversity of enteroviruses circulating in human populations. Therefore, monthly municipal wastewater samples were collected for 1 year and enteroviruses were quantified by reverse transcriptase quantitative PCR and identified by next-generation, high-throughput sequencing...
May 2017: MSphere
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