Insights into leaded gasoline registered in mud depocenters derived from multivariate statistical tool: southeastern Brazilian coast

2020 ◽  
Author(s):  
Bianca Sung Mi Kim ◽  
Rubens Cesar Lopes Figueira ◽  
José Lourenço Friedmann Angeli ◽  
Paulo Alves Lima Ferreira ◽  
Michel Michaelovich de Mahiques ◽  
...  
Keyword(s):  
Brazilian Coast ◽  
Multivariate Statistical ◽  
Statistical Tool ◽  
Leaded Gasoline

scholarly journals STATISTICAL MULTIVARIATE ANALYSIS APPLIED TO ENVIRONMENTAL CHARACTERIZATION OF SOIL IN SEMIARID REGION1

2019 ◽  
Vol 32 (1) ◽  
pp. 200-210
Author(s):  
Antônio Italcy de Oliveira Júnior ◽  
Luiz Alberto Ribeiro Mendonça ◽  
Sávio de Brito Fontenele ◽  
Adriana Oliveira Araújo ◽  
Maria Gorethe de Sousa Lima Brito
Keyword(s):  
Organic Matter Content ◽  
Principal Component ◽  
Matter Content ◽  
Multivariate Statistical ◽  
Statistical Tool ◽  
Environmental Characterization ◽  
Hierarchical Grouping ◽  
Two Factors ◽  
Total Data

ABSTRACT Soil is a dynamic and complex system that requires a considerable number of samples for analysis and research purposes. Using multivariate statistical methods, favorable conditions can be created by analyzing the samples, i.e., structural reduction and simplification of the data. The objective of this study was to use multivariate statistical analysis, including factorial analysis (FA) and hierarchical groupings, for the environmental characterization of soils in semiarid regions, considering anthropic (land use and occupation) and topographic aspects (altitude, moisture, granulometry, PR, and organic-matter content). As a case study, the São José Hydrographic Microbasin, which is located in the Cariri region of Ceará, was considered. An FA was performed using the principal component method, with normalized varimax rotation. In hierarchical grouping analysis, the “farthest neighbor” method was used as the hierarchical criterion for grouping, with the measure of dissimilarity given by the “square Euclidean distance.” The FA indicated that two factors explain 75.76% of the total data variance. In the analysis of hierarchical groupings, the samples were agglomerated in three groups with similar characteristics: one with samples collected in an area of the preserved forest and two with samples collected in areas with more anthropized soils. This indicates that the statistical tool used showed sensitivity to distinguish the most conserved soils and soils with different levels of anthropization.

scholarly journals Heavy Metals Analysis in Human Body (Toenail, Fingernail and Hair Samples) and Drinking Waters of Santa Fe Region, Argentina

2018 ◽  
pp. 1-14 ◽  
Author(s):  
J. I. Bungudu ◽  
L. Shuaibu ◽  
U. F. Mohammed ◽  
M. Alkali
Keyword(s):  
Heavy Metals ◽  
Drinking Water ◽  
Iron Concentration ◽  
Well Water ◽  
Santa Fe ◽  
Multivariate Statistical ◽  
Statistical Tool ◽  
Drinking Waters ◽  
Hair Samples ◽  
Arsenic Copper

This study provides an insight into a province of Santa Fe region of a developing country, namely San Cristobal and Huanqueros, Argentina and a possible link between arsenic, copper and iron concentration in toenail, fingernail and hair in the population. A multivariate statistical tool, known as Principal Component Analysis (PCA) was applied to explain the behaviour of the elements in toenails, fingernails, drinking waters and hair using multi- base 2013 excel add- ins. Correlation test, error bars, and a 2-factor ANOVA test were employed. Results from one hundred and twenty- nine (n=129) samples of tap well water (n=23), rainwater (n=20), bottled water (n=6) and treated well water (n=80) and each of toenail, fingernail and hair (n=129) samples from the subjects were determined and the results compared with the previous works. Mean, standard deviation, covariance and maximum and minimum for each variable were reported. The hypothesis is to understand if there is a correlation between fingernail and toenail metals levels and make a comparison with previous researches. Results show that a positive correlation exists between fingernail and toenail metals concentrations. Also, the study reveals higher concentrations of arsenic, copper and iron in the samples tissues compared with the values available in the previous works. The elevated levels of these metals may be attributed to the drinking water sources. Since this study highlighted elevated levels of these metals, consumptions of contaminated drinking water should be constantly monitored. Finally, the application of multivariate statistical techniques can provide powerful information on heavy metals bioaccumulation analysis in human and environment.

scholarly journals Evaluation of a multiple and global analytical indicator of batch consistency: traditional Chinese medicine injection as a case study

RSC Advances ◽  
2020 ◽  
Vol 10 (17) ◽  
pp. 10338-10351 ◽  
Author(s):  
Libing Chen ◽  
Fang Zhao ◽  
Wenzhu Li ◽  
Zeqi Chen ◽  
Jianyang Pan ◽  
...  
Keyword(s):  
Chinese Medicine ◽  
Traditional Chinese Medicine ◽  
Multivariate Statistical ◽  
Statistical Tool

Evaluation of a multiple and global analytical indicator of batch consistency was employed in TCMIs with a multivariate statistical tool.

Vocational Rehabilitation Closure Statuses in the United States: Generalizing to the Hispanic/Latino Ethnicity

2005 ◽  
Vol 36 (2) ◽  
pp. 4-11 ◽  
Author(s):  
Keith B. Wilson
Keyword(s):  
United States ◽  
African American ◽  
Vocational Rehabilitation ◽  
The United States ◽  
Test Statistic ◽  
Multivariate Statistical ◽  
Statistical Tool ◽  
Black African ◽  
Significant Difference ◽  
Race Ethnicity

Vocational Rehabilitation (VR) research focusing on race, ethnicity and other demographic variables has continued to gain needed attention in the VR literature over the past ten years. In the study described here, the Chi-squared Automatic Interaction Detector (CHAID), an exploratory multivariate statistical tool from Answer Tree (SPSS, 2001), was used to investigate closure codes (statuses) with Race, Ethnicity, Age, and Gender. The test statistic revealed a statistically significant difference with the Hispanic ethnicity, age, and types of closures with the race (i.e., African American and White American) of customers in the United States VR system. Particularly, customers who are non-Hispanic (African Americans) between the ages of 51-60 are more likely not to be accepted for VR services (Status 08 from 02) and once accepted for VR services, close not rehabilitated (Statuses 28,30, & closed from pre-service, Status 38 from Status 04). Results further indicated that Black (African American) and White (European American) Hispanics in the United States VR system tend to have different experiences. Suggestions for VR counselors are discussed.

scholarly journals Spatial and seasonal variability in the water chemistry of Kabar Tal wetland (Ramsar site), Bihar, India: multivariate statistical techniques and GIS approach

2021 ◽  
Author(s):  
Deepak Gupta ◽  
Rajesh Kumar Ranjan ◽  
Purushothaman Parthasarathy ◽  
Afroz Ansari
Keyword(s):  
Electrical Conductivity ◽  
Major Ions ◽  
Chemical Species ◽  
Temporal Distribution ◽  
Ramsar Site ◽  
Multivariate Statistical ◽  
Statistical Tool ◽  
Major Cations ◽  
Different Seasons ◽  
Major Anions

Abstract This study was performed to evaluate the spatial and temporal distribution of major ions in water samples of a newly designated Ramsar site, namely Kabar Tal (KT) wetland of Bihar. Samples were collected during summer, monsoon, and winter seasons. The analytical and GIS results show that concentration of electrical conductivity, chloride, and nitrate are higher in summer than monsoon and winter. However, the concentration of major cations such as sodium, potassium, calcium, and magnesium are higher in winter than monsoon and summer. In addition, major anions like sulphate and phosphate concentration is higher during monsoon than summer and winter. Multivariate statistical tool (Discriminant Analysis) results suggest that temperature, pH, electrical conductivity, sulphate, and potassium are the major parameters distinguishing the water quality in different seasons. The study confirms that seasonal variations are playing a major role in the hydrochemistry of KT wetland. Overall, this work outlines the approach towards proper conservation and utilization of wetlands and to assess the quality of surface water for determining its suitability for agricultural purposes. Overall, this work highlights the approach towards estimating the seasonal dynamics of chemical species in KT wetland and its suitability for irrigation purposes.

Long-term variations in individual particle types in the aerosol of Phoenix, Arizona, as determined using automated electron microprobe analysis and multivariate statistical techniques

1993 ◽  
Vol 51 ◽  
pp. 742-743
Author(s):  
Karen A. Katrinak ◽  
James R. Anderson ◽  
Peter R. Buseck
Keyword(s):  
Electron Microprobe ◽  
Fine Fraction ◽  
Coarse Fraction ◽  
Motor Vehicles ◽  
Multivariate Statistical Methods ◽  
Multivariate Statistical ◽  
X Ray ◽  
Mineral Particles ◽  
Anthropogenic Air Pollutants

Aerosol samples were collected in Phoenix, Arizona on eleven dates between July 1989 and April 1990. Elemental compositions were determined for approximately 1000 particles per sample using an electron microprobe with an energy-dispersive x-ray spectrometer. Fine-fraction samples (particle cut size of 1 to 2 μm) were analyzed for each date; coarse-fraction samples were also analyzed for four of the dates.The data were reduced using multivariate statistical methods. Cluster analysis was first used to define 35 particle types. 81% of all fine-fraction particles and 84% of the coarse-fraction particles were assigned to these types, which include mineral, metal-rich, sulfur-rich, and salt categories. "Zero-count" particles, consisting entirely of elements lighter than Na, constitute an additional category and dominate the fine fraction, reflecting the importance of anthropogenic air pollutants such as those emitted by motor vehicles. Si- and Ca-rich mineral particles dominate the coarse fraction and are also numerous in the fine fraction.

Angular Calibration of Ribosomal Subuntts in Factor Space

1990 ◽  
Vol 48 (1) ◽  
pp. 462-463
Author(s):  
Minakhi Pujari ◽  
Joachim Frank
Keyword(s):  
Three Dimensional ◽  
Carbon Layer ◽  
Uranyl Acetate ◽  
Particle Analysis ◽  
Factor Space ◽  
Multivariate Statistical ◽  
Ribosomal Subunits ◽  
Layer Method ◽  
Dimensional Reconstruction ◽  
Number Of Particles

In single-particle analysis of macromolecule images with the electron microscope, variations of projections are often observed that can be attributed to the changes of the particle’s orientation on the specimen grid (“rocking”). In the multivariate statistical analysis (MSA) of such projections, a single factor is often found that expresses a large portion of these variations. Successful angle calibration of this “rocking factor” would mean that correct angles can be assigned to a large number of particles, thus facilitating three-dimensional reconstruction.In a study to explore angle calibration in factor space, we used 40S ribosomal subunits, which are known to rock around an axis approximately coincident with their long axis. We analyzed micrographs of a field of these particles, taken with 20° tilt and without tilt, using the standard methods of alignment and MSA. The specimen was prepared with the double carbon-layer method, using uranyl acetate for negative staining. In the MSA analysis, the untilted-particle projections were used as active, the tilted-particle projections as inactive objects. Upon tilting, those particles whose rocking axes are parallel to the tilt axis will change their appearance in the same way as under the influence of rocking. Therefore, each vector, in factor space, joining a tilted and untilted projection of the same particle can be regarded as a local 20-degree calibration bar.

Molecular Views of Ice-Embedded Lumbricus Terrestris Erythrocruorin Obtained By Invariant Classification

1990 ◽  
Vol 48 (1) ◽  
pp. 450-451
Author(s):  
Michael schatz ◽  
Joachim Jäger ◽  
Marin van Heel
Keyword(s):  
Image Interpretation ◽  
Lumbricus Terrestris ◽  
Reference Image ◽  
Large Set ◽  
Multivariate Statistical ◽  
Data Set ◽  
Low Contrast ◽  
Negative Stain ◽  
Reference Images ◽  
Statistical Resolution

Lumbricus terrestris erythrocruorin is a giant oxygen-transporting macromolecule in the blood of the common earth worm (worm "hemoglobin"). In our current study, we use specimens (kindly provided by Drs W.E. Royer and W.A. Hendrickson) embedded in vitreous ice (1) to avoid artefacts encountered with the negative stain preparation technigue used in previous studies (2-4).Although the molecular structure is well preserved in vitreous ice, the low contrast and high noise level in the micrographs represent a serious problem in image interpretation. Moreover, the molecules can exhibit many different orientations relative to the object plane of the microscope in this type of preparation. Existing techniques of analysis requiring alignment of the molecular views relative to one or more reference images often thus yield unsatisfactory results.We use a new method in which first rotation-, translation- and mirror invariant functions (5) are derived from the large set of input images, which functions are subsequently classified automatically using multivariate statistical techniques (6). The different molecular views in the data set can therewith be found unbiasedly (5). Within each class, all images are aligned relative to that member of the class which contributes least to the classes′ internal variance (6). This reference image is thus the most typical member of the class. Finally the aligned images from each class are averaged resulting in molecular views with enhanced statistical resolution.

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