scholarly journals Subsampling of Regional-Scale Database for improving Multivariate Analysis Interpretation of Groundwater Chemical Evolution and Ion Sources

Geosciences ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 139
Author(s):  
Julien Walter ◽  
Romain Chesnaux ◽  
Damien Gaboury ◽  
Vincent Cloutier
Keyword(s):  
Chemical Evolution ◽  
Flow Line ◽  
Regional Scale ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Point Of View ◽  
Statistical Point ◽  
Critical Elements ◽  
Chemical Background ◽  
Statistical Representativeness

: Multivariate statistics are widely and routinely used in the field of hydrogeochemistry. Trace elements, for which numerous samples show concentrations below the detection limit (censored data from a truncated dataset), are removed from the dataset in the multivariate treatment. This study now proposes an approach that consists of avoiding the truncation of the dataset of some critical elements, such as those recognized as sensitive elements regarding human health (fluoride, iron, and manganese). The method aims to reduce the dataset to increase the statistical representativeness of critical elements. This method allows a robust statistical comparison between a regional comprehensive dataset and a subset of this regional database. The results from hierarchical Cluster analysis (HCA) and principal component analysis (PCA) were generated and compared with results from the whole dataset. The proposed approach allowed for improvement in the understanding of the chemical evolution pathways of groundwater. Samples from the subset belong to the same flow line from a statistical point of view, and other samples from the database can then be compared with the samples of the subset and discussed according to their stage of evolution. The results obtained after the introduction of fluoride in the multivariate treatment suggest that dissolved fluoride can be gained either from the interaction of groundwater with marine clays or from the interaction of groundwater with Precambrian bedrock aquifers. The results partly explain why the groundwater chemical background of the region is relatively high in fluoride contents, resulting in frequent excess in regards to drinking water standards.

scholarly journals Influence of Pasteurization on Total Phenols Content and Antioxidant Capacity of Prunus persica L. Juices

2017 ◽  
Vol 45 (2) ◽  
pp. 553-560 ◽  
Author(s):  
Vasile LASLO ◽  
Alin C. TEUSDEA ◽  
Sonia A. SOCACI ◽  
Daniel MIERLITA ◽  
Simona I. VICAS
Keyword(s):  
Antioxidant Capacity ◽  
Prunus Persica ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Quality Parameters ◽  
Point Of View ◽  
Total Phenolic ◽  
Total Phenols ◽  
The European Union ◽  
Important Place

Peach and nectarine (Prunus persica ) production has an important place in the world, being the most important fruit after apple crops in the European Union. Because the fruits are perishable, it is desirable to valorize them as juice. Seven peaches and three nectarines cultivars grown in the N-W part of Romania were investigated for quality parameters, volatile profile, total phenols content and antioxidant capacity. The volatile composition of peach and nectarine cultivars was determined via the ITEX/GC-MS technique, the main volatile compounds belonging to alcohols and aldehydes. Another objective was to obtain the pasteurised juices from these fruits and to investigate the best time of pasteurisation in order to identify the most valuable cultivar from the perspective of total phenols content and its antioxidant capacity. For a better interpretation of results and a proper discrimination between cultivars, according to the total phenols content and antioxidant capacity, the multivariate analysis, Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were applied. The peach cultivars showed the highest content in total phenols compared with nectarine. From peach cultivars, the highest concentration was recorded in ‘Southland’ (47.49 ± 0.14 mg GAE 100 g-1 FW) and from nectarine cultivars in ‘Romamer’ (16.28 ± 0.83 mg GAE 100 g-1 FW). The highest antioxidant capacities were recorded in ‘Southland’ peach in the case of both methods (DPPH and FRAP). The results showed that ‘Southland’ peach and ‘Romamer’ nectarine pasteurised juices are the best from the point of view of total phenolic compounds content with high antioxidant capacity.

scholarly journals Analysis of Regional Disparities in Agriculture Focusing on Economically Weak Regions of the Czech Republic

2019 ◽  
Vol 50 (2) ◽  
pp. 141-153
Author(s):  
J. Sirohi ◽  
G. Kukalová ◽  
L. Moravec
Keyword(s):  
Cluster Analysis ◽  
Czech Republic ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Point Of View ◽  
The Czech Republic ◽  
Border Regions ◽  
Agriculture Industry ◽  
Bartlett’S Test ◽  
Input Variables

Abstract The objective of this study is to identify the regions of the Czech Republic with the economically non-effective agriculture industry. The methodology is based on an orginal approach as the economically weak regions are identified on the LAU 1 level, comparing to the existing studies using only NUTS III level. The input data describe the economic results of 6,031 agricultural entities from 75 different regions LAU 1. The data covering the period between 2006 and 2014 were gained from the database Amadeus. The study deploys the methods of Principal Component Analysis, Kaiser-Meier-Olkin test, Bartlett’s test and hierarchical cluster analysis. The study determinates two key components: the Company Size and the Company Profit. These key components are used as the input variables for the cluster analysis. The cluster analysis identifies four clusters of regions from the agricultural entities economical results point of view. Subsequently the Standardized Variable Method is used to determinate the mutual order of the regions. The results of LAU 1 regions analyses show that the agrucultural entities, located in the border regions, reach economical results below average of the Czech Republic regions.

Sizing & Allocation in Labour Market: business strategies and multivariate analysis

2021 ◽  
pp. 121-124
Author(s):  
Andrea Marletta
Keyword(s):  
Multivariate Analysis ◽  
Labour Market ◽  
Qualitative Interviews ◽  
Principal Component ◽  
Business Environment ◽  
Point Of View ◽  
Accurate Analysis ◽  
Statistical Point ◽  
Business Context ◽  
Potential Index

In Labour Market, the issue of Sizing and Allocation is a discussed problem. In this study, this topic has been considered from a statistical point of view. Indeed, the choice to change the number of your team of employees in a business context needs a very accurate analysis. If for example a firm decides to launch a new product on the market, it could be necessary to recruit new resources. The proposed statistical approach aims to give some hints about the total number of employees analysing the features of the existing market and the territorial geography. From a statistical point of two techniques of multivariate analysis have been presented as exploratory tools. In the application, a Principal Component Analysis has been used to investigate the business environment after some qualitative interviews to the board of the company. In a second step, some different scenarios have been proposed to determine the exact number of new resources using a data hybridization technique including internal and external sources. Finally, the allocation of the new hired of the scenarios on the Italian territory has been achieved thanks to the construction of a territorial potential index.

A Comparative Evaluation of Serum and Salivary Total Proteins and Immunoglobulins in Patients with Hepatitis A and Healthy Subjects

2018 ◽  
Vol 69 (5) ◽  
pp. 1125-1128
Author(s):  
Daniela G. Balan ◽  
Dan Piperea Sianu ◽  
Iulia I. Stanescu ◽  
Dorin Ionescu ◽  
Andra Elena Stroescu Balcangiu ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Comparative Evaluation ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Point Of View ◽  
Healthy Individuals ◽  
Total Proteins ◽  
Statistical Point ◽  
Immunological Tests ◽  
Acute Hepatitis A

Assessment of changes in total proteins level, serum and saliva IgG and IgA levels, serum IgM level, serum and saliva IgA/IgG ratio. The study was conducted on a group of 40 subjects, divided into 2 lots: the first lot consisting of 20 healthy individuals and the second consisting of 20 patients with hepatitis with hepatitis A virus (HAV). The levels of total proteins, serum and saliva IgG and IgA, serum IgM and serum and saliva IgA/IgG ratio have higher values in patients with hepatitis A, in comparison to healthy subjects, without necessarily exceeding the maximum admitted value. The results are significant from a statistical point of view. Due to the sensitivity and specificity of salivary anti-HAV IgM and IgG in patients with acute hepatitis A, compared with healthy subjects, there is a possibility of using salivary immunological tests instead of serum tests for the diagnosis and epidemiological study of HAV infection.

The Importance of Rainfall Distribution in Urban Drainage Operation

1992 ◽  
Vol 23 (2) ◽  
pp. 121-136 ◽  
Author(s):  
Fons Nelen ◽  
Annemarieke Mooijman ◽  
Per Jacobsen
Keyword(s):  
Real Time ◽  
Treatment Plant ◽  
Rain Gauge ◽  
Point Of View ◽  
Rain Event ◽  
Real Time Control ◽  
Rainfall Distribution ◽  
Statistical Point ◽  
Time Control ◽  
Spatially Distributed

A control simulation model, called LOCUS, is used to investigate the effects of spatially distributed rain and the possibilities to benefit from this phenomenon by means of real time control. The study is undertaken for a catchment in Copenhagen, where rainfall is measured with a network of 8 rain gauges. Simulation of a single rain event, which is assumed to be homogeneous, i.e. using one rain gauge for the whole catchment, leads to large over- and underestimates of the systems output variables. Therefore, when analyzing a single event the highest possible degree of rainfall information may be desired. Time-series simulations are performed for both an uncontrolled and a controlled system. It is shown that from a statistical point of view, rainfall distribution is NOT significant concerning the probability of occurrence of an overflow. The main contributing factor to the potential of real time control, concerning minimizing overflows, is to be found in the system itself, i.e. the distribution of available storage and discharge capacity. When other operational objectives are involved, e.g., to minimize peak flows to the treatment plant, rainfall distribution may be an important factor.

Quality evaluation of tugaksheeree samples by ATR-FTIR spectroscopy using multicomponent analysis

2020 ◽  
Vol 10 ◽  
Author(s):  
Nikunj D. Patel ◽  
Niranjan S. Kanaki
Keyword(s):  
Principal Component Analysis ◽  
Cluster Analysis ◽  
Quality Evaluation ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Attenuated Total Reflectance ◽  
Chemometric Methods ◽  
Total Reflectance ◽  
Fingerprint Region ◽  
Ftir Technique

Background: Numerous Ayurvedic formulations contains tugaksheeree as key ingredient. Tugaksheereeis the starch gained from the rhizomes of two plants, Curcuma angustifoliaRoxb. (Zingiberaceae) and Marantaarundinacea (MA) Linn. (Marantaceae). Objective: The primary concerns in quality assessment of Tugaksheeree occur due to adulteration or substitution. Method: In current study, Fourier transform infrared (FTIR) technique with attenuated total reflectance (ATR) facility was used to evaluate tugaksheeree samples. Total 10 different samples were studied and transmittance mode was kept to record the spectra devoid of pellets of KBR. Further treatment was given with multi component tools by considering fingerprint region of the spectra. Multivariate analysis was performed by various chemometric methods. Result: Multi component methods like Principal Component Analysis (PCA), and Hierarchical Cluster Analysis (HCA)were used to discriminate the tugaksheeree samples using Minitab software. Conclusion: This method can be used as a tool to differentiate samples of tugaksheeree from its adulterants and substitutes.

scholarly journals Multivariate Statistical Approach for Nephrines in Women with Obesity

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1393
Author(s):  
Ralitsa Robeva ◽  
Miroslava Nedyalkova ◽  
Georgi Kirilov ◽  
Atanaska Elenkova ◽  
Sabina Zacharieva ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Metabolic Syndrome ◽  
Data Analysis ◽  
Stress Response ◽  
Exploratory Data Analysis ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Obese Women ◽  
Exploratory Data

Catecholamines are physiological regulators of carbohydrate and lipid metabolism during stress, but their chronic influence on metabolic changes in obese patients is still not clarified. The present study aimed to establish the associations between the catecholamine metabolites and metabolic syndrome (MS) components in obese women as well as to reveal the possible hidden subgroups of patients through hierarchical cluster analysis and principal component analysis. The 24-h urine excretion of metanephrine and normetanephrine was investigated in 150 obese women (54 non diabetic without MS, 70 non-diabetic with MS and 26 with type 2 diabetes). The interrelations between carbohydrate disturbances, metabolic syndrome components and stress response hormones were studied. Exploratory data analysis was used to determine different patterns of similarities among the patients. Normetanephrine concentrations were significantly increased in postmenopausal patients and in women with morbid obesity, type 2 diabetes, and hypertension but not with prediabetes. Both metanephrine and normetanephrine levels were positively associated with glucose concentrations one hour after glucose load irrespectively of the insulin levels. The exploratory data analysis showed different risk subgroups among the investigated obese women. The development of predictive tools that include not only traditional metabolic risk factors, but also markers of stress response systems might help for specific risk estimation in obesity patients.

scholarly journals Spectroscopy as a useful tool for the identification of changes with time in post-mortem vitreous humor for forensic toxicology purposes

2021 ◽  
Author(s):  
Anna Wójtowicz ◽  
Agata Mitura ◽  
Renata Wietecha-Posłuszny ◽  
Rafał Kurczab ◽  
Marcin Zawadzki
Keyword(s):  
Ir Spectra ◽  
Forensic Toxicology ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Vitreous Humor ◽  
Attenuated Total Reflection ◽  
Glass Slides ◽  
Added Benefit ◽  
Ft Ir ◽  
Non Destructive

AbstractVitreous humor (VH) is an alternative biological matrix with a great advantage of longer availability for analysis due to the lack of many enzymes. The use of VH in forensic toxicology may have an added benefit, however, this application requires rapid, simple, non-destructive, and relatively portable analytical analysis methods. These requirements may be met by Fourier transform infrared spectroscopy technique (FT-IR) equipped with attenuated total reflection accessory (ATR). FT-IR spectra of vitreous humor samples, deposited on glass slides, were collected and subsequent chemometric data analysis by means of Hierarchical Cluster Analysis and Principal Component Analysis was conducted. Differences between animal and human VH samples and human VH samples stored for diverse periods of time were detected. A kinetic study of changes in the VH composition up to 2 weeks showed the distinction of FT-IR spectra collected on the 1st and 14th day of storage. In addition, data obtained for the most recent human vitreous humor samples—collected 3 and 2 years before the study, presented successful discrimination of all time points studied. The method introduced was unable to detect mephedrone addition to VH in the concentration of 10 µg/cm3. Graphic abstract

scholarly journals A Methodology Based on FT-IR Data Combined with Random Forest Model to Generate Spectralprints for the Characterization of High-Quality Vinegars

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1411
Author(s):  
José Luis P. Calle ◽  
Marta Ferreiro-González ◽  
Ana Ruiz-Rodríguez ◽  
Gerardo F. Barbero ◽  
José Á. Álvarez ◽  
...  
Keyword(s):  
Random Forest ◽  
Raw Materials ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Raw Material ◽  
Support Vector ◽  
Protected Designation Of Origin ◽  
Ft Ir

Sherry wine vinegar is a Spanish gourmet product under Protected Designation of Origin (PDO). Before a vinegar can be labeled as Sherry vinegar, the product must meet certain requirements as established by its PDO, which, in this case, means that it has been produced following the traditional solera and criadera ageing system. The quality of the vinegar is determined by many factors such as the raw material, the acetification process or the aging system. For this reason, mainly producers, but also consumers, would benefit from the employment of effective analytical tools that allow precisely determining the origin and quality of vinegar. In the present study, a total of 48 Sherry vinegar samples manufactured from three different starting wines (Palomino Fino, Moscatel, and Pedro Ximénez wine) were analyzed by Fourier-transform infrared (FT-IR) spectroscopy. The spectroscopic data were combined with unsupervised exploratory techniques such as hierarchical cluster analysis (HCA) and principal component analysis (PCA), as well as other nonparametric supervised techniques, namely, support vector machine (SVM) and random forest (RF), for the characterization of the samples. The HCA and PCA results present a clear grouping trend of the vinegar samples according to their raw materials. SVM in combination with leave-one-out cross-validation (LOOCV) successfully classified 100% of the samples, according to the type of wine used for their production. The RF method allowed selecting the most important variables to develop the characteristic fingerprint (“spectralprint”) of the vinegar samples according to their starting wine. Furthermore, the RF model reached 100% accuracy for both LOOCV and out-of-bag (OOB) sets.

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