Effect of Spectral Shifts on the Resolution of trans-1-(2-Naphthyl)-2-phenylethene Conformer UV Spectra Based on Principal Component Analysis with Self-Modeling

1994 ◽  
Vol 98 (50) ◽  
pp. 13162-13170 ◽  
Author(s):  
Jack Saltiel ◽  
Jong-Oh Choi ◽  
Donald F. Sears ◽  
David W. Eaker ◽  
Frank B. Mallory ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Principal Component ◽  
Component Analysis ◽  
Uv Spectra ◽  
Spectral Shifts

scholarly journals A principal component analysis of quasar UV spectra atz ~  3

2011 ◽  
Vol 530 ◽  
pp. A50 ◽  
Author(s):  
I. Pâris ◽  
P. Petitjean ◽  
E. Rollinde ◽  
E. Aubourg ◽  
N. Busca ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Principal Component ◽  
Component Analysis ◽  
Uv Spectra

scholarly journals Principal Component Analysis of Phenolic Acid Spectra

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Ronald A. Holser
Keyword(s):  
Principal Component Analysis ◽  
Ir Spectra ◽  
Phenolic Acids ◽  
Phenolic Acid ◽  
Principal Component ◽  
Component Analysis ◽  
Uv Spectra ◽  
Classification Model ◽  
Plant Metabolites ◽  
Spectral Models

Phenolic acids are common plant metabolites that exhibit bioactive properties and have applications in functional food and animal feed formulations. The ultraviolet (UV) and infrared (IR) spectra of four closely related phenolic acid structures were evaluated by principal component analysis (PCA) to develop spectral models for their rapid detection. Results demonstrated that UV and IR spectra could discriminate between each of the phenolic acids in overall models. Calculation of model scores and loadings showed that derivative UV spectra accounted for 99% variation with 2 principal components (PC) while derivative IR spectra required 3 PCs. Individual PCA models were developed for ferulic acid and p-coumaric acid using derivative UV spectra for detection and classification by soft independent modeling of class analogy (SIMCA). The application of this spectral technique as a classification model is expected to promote the use of agricultural residues as a source of these phenolic compounds.

scholarly journals Chemical Fingerprinting by RP-RRLC-DAD and Principal Component Analysis of Ziziphora clinopodioides from Different Locations

2012 ◽  
Vol 7 (9) ◽  
pp. 1934578X1200700
Author(s):  
Shuge Tian ◽  
Qian Yu ◽  
Lude Xin ◽  
Zhaohui Sunny Zhou ◽  
Halmuart· Upur
Keyword(s):  
Principal Component Analysis ◽  
Principal Component ◽  
Component Analysis ◽  
Reversed Phase ◽  
Uv Spectra ◽  
Active Components ◽  
Photodiode Array Detection ◽  
Chemical Fingerprinting ◽  
Photodiode Array ◽  
Array Detection

An efficient and accurate fingerprinting method using reversed-phase rapid-resolution liquid-chromatography coupled with photodiode array detection has been developed and optimized to examine the variance in active compounds among Ziziphora clinopodioides Lam from different locations. Three active components, diosmin, linarin and pulegone, were identified by matching their retention times and UV spectra with the corresponding reference compounds. Our results indicated that chromatographic fingerprints, in combination with principal component analysis (PCA) and hierarchical clustering analysis (HCA), could efficiently identify and distinguish Z. clinopodioides from different sources. Our fingerprinting methods and data will be useful for quality control, and thus, more effective dosing in clinical application of Z. clinopodioides.

A German version of the Intermittent Claudication Questionnaire (ICQ): cultural adaptation and validation

VASA ◽  
2012 ◽  
Vol 41 (5) ◽  
pp. 333-342 ◽  
Author(s):  
Kirchberger ◽  
Finger ◽  
Müller-Bühl
Keyword(s):  
Principal Component Analysis ◽  
Intermittent Claudication ◽  
Completion Time ◽  
Short Form ◽  
Principal Component ◽  
Component Analysis ◽  
German Version ◽  
Average Completion Time ◽  
Sf 36 ◽  
Related Quality

Background: The Intermittent Claudication Questionnaire (ICQ) is a short questionnaire for the assessment of health-related quality of life (HRQOL) in patients with intermittent claudication (IC). The objective of this study was to translate the ICQ into German and to investigate the psychometric properties of the German ICQ version in patients with IC. Patients and methods: The original English version was translated using a forward-backward method. The resulting German version was reviewed by the author of the original version and an experienced clinician. Finally, it was tested for clarity with 5 German patients with IC. A sample of 81 patients were administered the German ICQ. The sample consisted of 58.0 % male patients with a median age of 71 years and a median IC duration of 36 months. Test of feasibility included completeness of questionnaires, completion time, and ratings of clarity, length and relevance. Reliability was assessed through a retest in 13 patients at 14 days, and analysis of Cronbach’s alpha for internal consistency. Construct validity was investigated using principal component analysis. Concurrent validity was assessed by correlating the ICQ scores with the Short Form 36 Health Survey (SF-36) as well as clinical measures. Results: The ICQ was completely filled in by 73 subjects (90.1 %) with an average completion time of 6.3 minutes. Cronbach’s alpha coefficient reached 0.75. Intra-class correlation for test-retest reliability was r = 0.88. Principal component analysis resulted in a 3 factor solution. The first factor explained 51.5 of the total variation and all items had loadings of at least 0.65 on it. The ICQ was significantly associated with the SF-36 and treadmill-walking distances whereas no association was found for resting ABPI. Conclusions: The German version of the ICQ demonstrated good feasibility, satisfactory reliability and good validity. Responsiveness should be investigated in further validation studies.

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