Integrated Principal Component Analysis ofMicrocystis aeruginosaDissolved Organic Matter and Assessment of UV-C Pre-Treatment on Cyanobacteria-Containing Water

2013 ◽  
Vol 42 (4) ◽  
pp. 442-448 ◽  
Author(s):  
Hua-Se Ou ◽  
Chao-Hai Wei ◽  
Yang Deng ◽  
Nai-Yun Gao
Keyword(s):  
Principal Component Analysis ◽  
Organic Matter ◽  
Principal Component ◽  
Component Analysis ◽  
Pre Treatment ◽  
Uv C

scholarly journals Characterization of soil chemical properties of strawberry fields using principal component analysis

2013 ◽  
Vol 37 (1) ◽  
pp. 168-176 ◽  
Author(s):  
Gláucia Oliveira Islabão ◽  
Marília Alves Brito Pinto ◽  
Lisiane Priscila Roldão Selau ◽  
Ledemar Carlos Vahl ◽  
Luís Carlos Timm
Keyword(s):  
Principal Component Analysis ◽  
Organic Matter ◽  
Soil Fertility ◽  
Organic Matter Content ◽  
Chemical Properties ◽  
Principal Component ◽  
Component Analysis ◽  
Soil Chemical Properties ◽  
Available Phosphorus ◽  
Very High

One of the largest strawberry-producing municipalities of Rio Grande do Sul (RS) is Turuçu, in the South of the State. The strawberry production system adopted by farmers is similar to that used in other regions in Brazil and in the world. The main difference is related to the soil management, which can change the soil chemical properties during the strawberry cycle. This study had the objective of assessing the spatial and temporal distribution of soil fertility parameters using principal component analysis (PCA). Soil sampling was based on topography, dividing the field in three thirds: upper, middle and lower. From each of these thirds, five soil samples were randomly collected in the 0-0.20 m layer, to form a composite sample for each third. Four samples were taken during the strawberry cycle and the following properties were determined: soil organic matter (OM), soil total nitrogen (N), available phosphorus (P) and potassium (K), exchangeable calcium (Ca) and magnesium (Mg), soil pH (pH), cation exchange capacity (CEC) at pH 7.0, soil base (V%) and soil aluminum saturation(m%). No spatial variation was observed for any of the studied soil fertility parameters in the strawberry fields and temporal variation was only detected for available K. Phosphorus and K contents were always high or very high from the beginning of the strawberry cycle, while pH values ranged from very low to very high. Principal component analysis allowed the clustering of all strawberry fields based on variables related to soil acidity and organic matter content.

Principal component analysis to assess the efficiency and mechanism for ultraviolet-C/polyaluminum chloride enhanced coagulation of algae-laden water

2013 ◽  
Vol 14 (3) ◽  
pp. 493-503
Author(s):  
Hua-Se Ou ◽  
Chao-Hai Wei ◽  
Yang Deng ◽  
Nai-Yun Gao
Keyword(s):  
Principal Component Analysis ◽  
Lake Taihu ◽  
Principal Component ◽  
Component Analysis ◽  
Polyaluminum Chloride ◽  
Algae Biomass ◽  
Principal Factors ◽  
P Factor ◽  
Uv C

Polyaluminum chloride (PAC) coagulation, short wavelength ultraviolet (UV-C at 254 nm) treatment and UV-C/PAC treatment of algae-laden water from Meiliang Gulf (Lake Taihu) were conducted. The intrinsic characteristics and correlations of chromophoric dissolved organic matter (CDOM), algae biomass and other contaminants were investigated. Parallel factor analysis determined four CDOM components, and principal component analysis (PCA) identified three integrated principal factors. PCA Factor 1 had correlations with dissolved organic carbon (DOC) (r = 0.798), UV254 (0.645), humic-like CDOM component C3 (0.892) and C4 (0.876), and Factor 2 correlated with in vivo chlorophyll-a (0.768), microcystin-LR (0.713), protein-like C1 (0.782) and C2 (0.759). Factor 3 had correlations with NH3-N (0.851) and total phosphorus (T-P) (0.716). The variation in PCA factor scores revealed that single PAC coagulation preferentially removed algal cells (Factor 2) but had little effect on NH3-N and T-P (Factor 3). Single UV-C treatment induced degradation of protein-like CDOM and decrease of algal biomass (Factor 2), followed by humic-like CDOM increase from ruptured cells (Factors 1 and 3). Compared with single PAC coagulation (20 mg L−1), the combined UV-C/PAC treatment (700 mJ cm−2 + 20 mg L−1) enhanced the removal of PCA Factors 1, 2 and 3 (15%, 32% and 10%).

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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