Samples Of Different Origin Research Articles

Identifying the underlying causes of biological instability in a full-scale drinking water supply system

Changes in bacterial concentration and composition in drinking water during distribution are often attributed to biological (in)stability. Here we assessed temporal biological stability in a full-scale distribution network (DN) supplied with different types of source water: treated and chlorinated surface water and chlorinated groundwater produced at three water treatment plants (WTP). Monitoring was performed weekly during 12 months in two locations in the DN. Flow cytometric total and intact cell concentration (ICC) measurements showed considerable seasonal fluctuations, which were different for two locations. ICC varied between 0.1–3.75 × 105 cells mL−1 and 0.69–4.37 × 105 cells mL−1 at two locations respectively, with ICC increases attributed to temperature-dependent bacterial growth during distribution. Chlorinated water from the different WTP was further analysed with a modified growth potential method, identifying primary and secondary growth limiting compounds. It was observed that bacterial growth in the surface water sample after chlorination was primarily inhibited by phosphorus limitation and secondly by organic carbon limitation, while carbon was limiting in the chlorinated groundwater samples. However, the ratio of available nutrients changed during distribution, and together with disinfection residual decay, this resulted in higher bacterial growth potential detected in the DN than at the WTP. In this study, bacterial growth was found to be higher (i) at higher water temperatures, (ii) in samples with lower chlorine residuals and (iii) in samples with less nutrient (carbon, phosphorus, nitrogen, iron) limitation, while this was significantly different between the samples of different origin. Thus drinking water microbiological quality and biological stability could change during different seasons, and the extent of these changes depends on water temperature, the water source and treatment. Furthermore, differences in primary growth limiting nutrients in different water sources could contribute to biological instability in the network, where mixing occurs.

Propagation and Titration of Influenza Viruses.

Influenza viruses are constantly circulating among humans, in which they cause seasonal epidemics of severe respiratory disease. Additionally, these zoonotic viruses infect different mammals and birds, from which new antigenic variants are occasionally transmitted to humans leading to devastating global pandemics. Surveillance programs, in which viruses from the main reservoir (waterfowl), intermediate hosts (like pigs and other farm animals), and other affected species are isolated and characterized, are crucial for the global influenza prevention strategy. This chapter gives an overview of the most commonly used methods for the propagation and titration of influenza viruses, which are key steps in surveillance procedures, as well as in vaccine development and basic research. Depending on the host and the viral strain, primary isolates are obtained from biological samples of different origin and subsequently amplified in embryonated chicken eggs or cell cultures. These propagation procedures are the focus of the first part of this chapter. Once the initial isolates have been amplified, virus titration methods based on particular characteristics of influenza viruses, such as their ability to agglutinate red blood cells (RBCs) or to induce cytopathic effects (CPE) in cell monolayers, are used to estimate the amount of viral particles. Such approaches, like the hemagglutination assay (HA assay), 50% tissue culture infectious dose (TCID50), or plaque assay, are included in the second part of this chapter. Although they are simple and cost-effective, some of these techniques have been partially replaced by faster and more sensitive methods based on the quantification of viral genomes, such as the quantitative real-time reverse transcription PCR (RT-qPCR), which is presented at the end of this section. The different protocols are explained in detail in order to facilitate the preparation and quantification of infectious virus stocks.

Radioactivity of Rock Samples of Different Origin (The Central Region of the Main Caucasian Range, Georgia)

Radioactivity of Rock Samples of Different Origin (The Central Region of the Main Caucasian Range, Georgia)

Trace Element Compositions and Defect Structures of High-Purity Quartz from the Southern Ural Region, Russia

Quartz samples of different origin from 10 localities in the Southern Ural region, Russia have been investigated to characterize their trace element compositions and defect structures. The analytical combination of cathodoluminescence (CL) microscopy and spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, and trace-element analysis by inductively coupled plasma mass spectrometry (ICP-MS) revealed that almost all investigated quartz samples showed very low concentrations of trace elements (cumulative concentrations of <50 ppm with <30 ppm Al and <10 ppm Ti) and low abundances of paramagnetic defects, defining them economically as “high-purity” quartz (HPQ) suitable for high-tech applications. EPR and CL data confirmed the low abundances of substitutional Ti and Fe, and showed Al to be the only significant trace element structurally bound in the investigated quartz samples. CL microscopy revealed a heterogeneous distribution of luminescence centres (i.e., luminescence active trace elements such as Al) as well as features of deformation and recrystallization. It is suggested that healing of defects due to deformation-related recrystallization and reorganization processes of the quartz lattice during retrograde metamorphism resulted in low concentrations of CL activator and other trace elements or vacancies, and thus are the main driving processes for the formation of HPQ deposits in the investigated area.

Variable Selection Applied to the Development of a Robust Method for the Quantification of Coffee Blends Using Mid Infrared Spectroscopy

This paper combined attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), multivariate calibration with partial least squares (PLS), and different variable selection methods for the development of models to determine Robusta-Arabica coffee blends in the analytical range from 0.0 to 33.0% w/w. Ground samples of different origins were roasted at three different levels: light, medium, and dark. Specific models were built for each roasting level, and a robust model was also obtained including all the samples. Mid infrared spectra were recorded in the wavenumber range between 4000 and 800 cm−1 for the 120 samples used in the models. Four variable selection methods were tested: genetic algorithm (GA), ordered predictors selection (OPS), successive projections algorithm (SPA), and interval PLS (iPLS). The best results were obtained using GA and OPS, decreasing root mean square errors of prediction (RMSEP) in 44–68% as compared to full spectra models. The best robust model was obtained with OPS, providing RMSEP of 1.8% w/w. The number of selected variable in the optimized models varied from 6.5 to 17.0% of the total number of original variables. This demonstrated the importance of selecting a limited number of wavenumbers richer in information specifically related to the analytes. All the methods were validated by estimating appropriate figures of merit and considered accurate, linear, sensitive, and unbiased.

Determination of chlorogenic acids and caffeine in homemade brewed coffee prepared under various conditions.

Coffee, a complex mixture of more than 800 volatile compounds, is one of the most valuable commodity in the world, whereas caffeine and chlorogenic acids (CGAs) are the most common compounds. CGAs are mainly composed of caffeoylquinic acids (CQAs), dicaffeoylquinic acids (diCQAs), and feruloylquinic acids (FQAs). The major CGAs in coffee are neochlorogenic acid (3-CQA), cryptochlorogenic acid (4-CQA), and chlorogenic acid (5-CQA). Many studies have shown that it is possible to separate the isomers of FQAs by high-performance liquid chromatography (HPLC). However, some authors have shown that it is not possible to separate 4-feruloylquinic acid (4-FQA) and 5-feruloylquinic acid (5-FQA) by HPLC. Therefore, the present study was designated to investigate the chromatographic problems in the determination of CGAs (seven isomers) and caffeine using HPLC-DAD. The values of determination coefficient (R2) calculated from external-standard calibration curves were >0.998. The recovery rates conducted at 3 spiking levels ranged from 99.4% to 106.5% for the CGAs and from 98.8% to 107.1% for the caffeine. The precision values (expressed as relative standard deviations (RSDs)) were <7% and <3% for intra and interday variability, respectively. The tested procedure proved to be robust. The seven CGAs isomers except 4-FQA and 5-FQA were well distinguished and all gave good peak shapes. We have found that 4-FQA and 5-FQA could not be separated using HPLC. The method was extended to investigate the effects of different brewing conditions such as the roasting degree of green coffee bean, coffee-ground size, and numbers of boiling-water pours, on the concentration of CGAs and caffeine in homemade brewed coffee, using nine green coffee bean samples of different origins. It was reported that medium-roasted, fine-ground coffees brewed using three pours of boiling water were the healthiest coffee with fluent CGAs.

Color and alcohol removal for the simultaneous detection of amino acids and sugars in wine by two-dimensional ion chromatography.

An effective pretreatment method for wine color removal by a PS-DVB SPE cartridge and online alcohol elimination by valve switching was presented. The optimum parameters for color removal were investigated: 40-μm and 100Å poly (styrene)-divinylbenzene (PS-DVB) (0.4g) was selected as the color removal material and 5mL of ethanol (10%) as the elution solvent for sample pretreatment under given condition. Moreover, an accurate and automated two-dimensional ion chromatography method for the simultaneous detection of amino acids and sugars was achieved with two valves after injection without alcohol interference. The method had a mean correlation coefficient of >0.99 and a repeatability of 0.92%-4.30% for eight replicates. The mean recovery of six red wine samples were 97.6%, 96.6%, 96.1%, 95.9%, 97.3% and 96.4% respectively. And this method successfully analyzed the amino acid and sugar contents of six wine samples of different origins.

Lack of evidence for microplastic contamination in honey

ABSTRACTHoney samples from Switzerland were investigated with regard to their microplastic particle burden. Five representative honey samples of different origin were processed following a standardized protocol to separate plastic-based microparticles from particles of natural origin, such as pollen, propolis, wax, and bee-related debris. The procedure was optimized to minimize post-sampling microplastic cross-contamination in the laboratory. The isolated microplastic particles were characterized and grouped by means of light microscopy as well as chemically characterized by microscopically coupled Raman and Fourier transform infrared spectroscopy. Five particle classes with an abundance significantly above blank levels were identified: black particles (particle count between 1760/kg and 8680/kg), white transparent fibres (particle count between 132/kg and 728/kg), white transparent particles (particle count between 60/kg and 172/kg), coloured fibres (particle count between 32/kg and 108/kg), and coloured particles (particle count between 8/kg and 64/kg). The black particles, which represented the majority of particles, were identified as char or soot and most probably originated from the use of smokers, a widespread practice in beekeeping. The majority of fibres were identified as cellulose or polyethylene terephthalate and were most likely of textile origin. In addition to these particle and fibre groups lower numbers of fragments were detected that were related to glass, polysaccharides or chitin, and few bluish particles contained copper phthalocyanine pigment. We found no indications that the honey samples were significantly contaminated with microplastic particles.

Untargeted screening of sulfonamides and their metabolites in salmon using liquid chromatography coupled to quadrupole Orbitrap mass spectrometry

An analytical method for the non-target screening of sulfonamides and metabolites in salmon was developed, using automated on-line extraction procedure followed by ultra-high performance liquid chromatography coupled to electrospray ionization quadrupole Orbitrap high-resolution mass spectrometry (UHPLC Q-Orbitrap), including three systematic workflows (i) fully non-targeted data acquisition with fragmentation, (ii) suspect library spectra searching followed by characteristic structural fragments filtering and (iii) confirmation of non-target analytes and structural characterization of unknown analytes based on the availability of reference standards. The estimated performance characteristics were satisfactory complying with the requirements of the guidelines specified in European Commission Decision 2002/657/EC. Four untargeted compounds were identified and confirmed from salmon samples of different origin taken from monitoring control program.

Effect of overdischarge (overlithiation) on electrochemical properties of LiMn2O4 samples of different origin

Overreaching certain minimum allowable voltage upon discharging a lithium-ion battery (overdischarge) leads to the insertion of an overstoichiometric amount of lithium into a cathode material and causes its degradation. Here we establish overdischarge tolerance margins for two samples of LiNi0.5Mn1.5O4, A commercial coarse-grained material by NEI reversibly inserts/releases ~ 0.37 gram equivalent of extra lithium ions in the 2.25–3.5 V region and ~ 0.75 gram equivalent of extra lithium ions in the 1.885–3.5 V region. It perfectly behaves in life tests (225 cycles) restoring its performance upon switching from a “non-standard” (2.25–5.0 V) to a “standard” (3.5–5.0 V) charge/discharge regime, in spite of a fast capacity fade within the widened voltage limit. A homemade fine-grained material does not tolerate even slightest overdischarge. It inserts/releases ~ 0.75 gram equivalent of extra lithium ions just in the 2.25–3.5 V region and quickly degrades either upon extending the voltage region to 1.885 V or in long-term cycling with switching from a “standard” to “non-standard” charge/discharge regime. Formation of Li1.375Ni0.5Mn1.5O4 and Li1.75Ni0.5Mn1.5O4 compounds upon overlithiation is explained by the transformation of the mother cubic $$ Fd\overline{3}m $$ structure to the rhombohedral $$ R\overline{3}m $$ structure with empty sites of proper multiplicity, which are able to accommodate 0.375 and 0.75 gram equivalents of extra Li+.

Fabric Phase Sorptive Extraction Explained

The theory and working principle of fabric phase sorptive extraction (FPSE) is presented. FPSE innovatively integrates the benefits of sol–gel coating technology and the rich surface chemistry of cellulose/polyester/fiberglass fabrics, resulting in a microextraction device with very high sorbent loading in the form of an ultra-thin coating. This porous sorbent coating and the permeable substrate synergistically facilitate fast extraction equilibrium. The flexibility of the FPSE device allows its direct insertion into original, unmodified samples of different origin. Strong chemical bonding between the sol–gel sorbent and the fabric substrate permits the exposure of FPSE devices to any organic solvent for analyte back-extraction/elution. As a representative sorbent, sol–gel poly(ethylene glycol) coating was generated on cellulose substrates. Five (cm2) segments of these coated fabrics were used as the FPSE devices for sample preparation using direct immersion mode. An important class of environmental pollutants—substituted phenols—was used as model compounds to evaluate the extraction performance of FPSE. The high primary contact surface area (PCSA) of the FPSE device and porous structure of the sol–gel coatings resulted in very high sample capacities and incredible extraction sensitivities in a relatively short period of time. Different extraction parameters were evaluated and optimized. The new extraction devices demonstrated part per trillion level detection limits for substitute phenols, a wide range of detection linearity, and good performance reproducibility.

Изучение генетического разнообразия сортообразцов тополя (populus l.) на основе ssr-маркеров

The object of the research were 28 plants with valuable breeding genotypes of the initial 40-year-old variety-testing cultures of white poplar (Populus alba L.), gray poplar (P. сanescens Sm.), presented by variety of samples of different origins. The purpose of the research was the selection of the most effective microsatellite primers for genetic identification of valuable breeding genotypes of poplar. The selection of high-polymorphic markers was conducted by testing a group of 12 SSR primers.

Direct measurement of nutrient concentrations in freshwaters with a miniaturized analytical probe: evaluation and validation

This work deals with the evaluation of the aqueous concentrations of dissolved reactive phosphorus (DRP), total phosphorus (TP), and ammonium nitrogen (N-NH4) in surface water by means of direct online instrumentation. A portable, submersible, and automated analyzer designed to measure dissolved and total nutrient concentrations characterized by miniaturization of the entire analytical process was tested against laboratory methods. A total number of 36 water samples of different origin (i.e., rain, river, lake, and sewage waters) were analyzed and used in the comparison of DRP, TP, and N-NH4 data. Raw data were distributed in a broad range of concentrations: 5-299μg P/L for DRP, 7-97μg P/L for TP, and 11-332μg N/L for N-NH4. Regression analysis underlined a high significant correlation between the measures of the probe and those of the laboratory (0.6<R 2<0.9; p<0.001) and pointed out the effectiveness of the new instrument in representing a broad range of nutrient concentrations.

Genetic Diversity and Antibiotic Resistance of Enterococcus faecalis Isolates from Traditional Korean Fermented Soybean Foods.

Eighty-five Enterococcus faecalis isolates collected from animals (40 isolates), meju (a Korean fermented soybean product; 27 isolates), humans (10 isolates), and various environmental samples (8 isolates) were subjected to multilocus sequence typing (MLST) to identify genetic differences between samples of different origins. MLST analysis resulted in 44 sequence types (STs), and the eBURST algorithm clustered the STs into 21 clonal complexes (CCs) and 17 singletons. The predominant STs, ST695 (21.1%, 18/85) and ST694 (9.4%, 8/85), were singletons, and only contained isolates originating from meju. None of the STs in the current study belonged to CC2 or CC9, which comprise clinical isolates with high levels of antibiotic resistance. The E. faecalis isolates showed the highest rates of resistance to tetracycline (32.9%), followed by erythromycin (9.4%) and vancomycin (2.4%). All isolates from meju were sensitive to these three antibiotics. Hence, MLST uncovered genetic diversity within E. faecalis, and clustering of the STs using eBURST revealed a correlation between the genotypes and origins of the isolates.

Covalent immobilization of rabbit-antiaflatoxin-antibodies onto the poly-acrylamideacrylonitrile as well as hybrid material UREASIL and developing an optical immunosensor

Abstract The aim of this work is to describe a covalent immobilization of antibodies onto the poly- acrylamide-acrylonitrile or hybrid material UREASIL and creation of optical immunosensor for determination of aflatoxin Bl. For this purpose, mouse-anti-aflatoxin B1 antibodies with oxidized carbohydrate moieties were covalently immobilized on the membranes of polyacrylamide- polyacrylonitrile copolymer, as well as the hybrid material UREASIL. To determine the affinity&gt; binding of the immobilized antibody with afatoxin Bl was used "sandwich" method. Associated with the immobilized antibody sought ingredients interact with a surplus of secondary’ signal antibodies. The described method has been developed as a model system, which can easily be applied for the determination of aflatoxins in samples of different origin. To the best of our knowledge, this is the first study to show that in the establishment of biosensor was used hybrid material UREASIL.

Characterization of natural vanilla flavour in foodstuff by HS‐SPME and GC‐C‐IRMS

AbstractVanillin can be obtained by extraction from the pods of Vanilla (organic vanillin), by synthetic pathways using different precursors (mainly lignin and guaiacol), and by enzymatic bioconversion (biovanillin) from natural precursors, (mainly ferulic acid, eugenol and isoeugenol, and turmeric acid). Based on the origins its commercial value greatly changes. At the same time the European Regulation allows to label food discriminating between the sources of the ingredient indicating the term ‘natural’ even if the ingredient is obtained by biosynthetic pathways. However from literature it is apparent that the distinction between synthetic and biosynthetic vanillin is not always possible, while the natural one can be easily discriminated, although rarely used. The method here proposed is based on head‐space solid‐phase microextraction and gas chromatography coupled to isotope ratio mass spectrometry to determine the carbon isotope ratio (δ13C) of vanillin extracted from vanilla pods, commercial flavoured foodstuff and in vanillin samples of different origins. Isotope fractionation during SPME extraction has been determined based on sample's isotopic composition. The results confirm the literature ones and allow to reveal which biovanillin can be easily characterized and distinguished from the synthetic ones. In most cases it has been possible to evaluate the origin of vanillin used in the different food preparations. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Investigation of Usability as Aggregate of Different Originated Rocks

The general properties of aggregate can determine the performance and durability of the concrete. In this study, mineralogical, petrographic, mechanical, physical and chemical properties of the rock samples of different origin (limestone, recrystallized limestone, dolomite, sand and gravel, tephra-phonolite, trachybasalt) were determined. Samples were obtained from different origin rocks units and they have been classified in three different sizes of aggregate with crushing and screening method. Grading, classification of particle, loose bulk density, water absorption ratio, flakiness index, coefficient of Los Angeles, resistance to freeze-loosening and alkali-silica reaction of aggregates and organic matter determination has been determined. The rocks have been investigated in compliance with the relevant standards. Trachybasalt and dolomite have higher particle density than other rocks. In addition, strength and flexural strength of these rocks are higher than other rocks. Tephra-phonolite has the lowest water absorption rate. At the same time resistance to freeze loosening of Tephra- phonolite is lower than the other rocks. Resistance to fragmentation and the resistance to wear of all of rocks are quite high. Sand and gravel, tephra-phonolite and trachybasalt are evaluated in terms of alkali-silica reaction. Sand and gravel are more reactive than the other aggregates. Organic matter content of the aggregates is low for the quality of aggregate. Also high correlation between some properties of aggregates was observed. For example, high correlation between compressive strength and flexural strength, water absorption and porosity, resistance to fragmentation and the resistance to ware (Micro-Deval).

Simultaneous Quantification of Antioxidant Compounds in Phellinus igniarius Using Ultra Performance Liquid Chromatography-Photodiode Array Detection-Electrospray Ionization Tandem Mass Spectrometry.

Natural antioxidants are widely used in the life sciences. Phellinus igniarius is a historically used natural antioxidant containing a variety of active compounds. Phenols, particularly Inoscavin A and Hypholomine B, are found in the high concentrations. Better quantitative methods are needed to perform quality control in order to support further research of this mushroom. An ultra-performance liquid chromatography method coupled to photodiode-array detection and an electrospray ionization tandem mass spectrometry method (UPLC-PAD-MS) was developed to simultaneously quantify Inoscavin A and Hypholomine B levels in the medicinal fungus Phellinus igniarius. The two compounds were quantified using UPLC-PAD and UPLC-MS. The methods were accurate (mean accuracy for spiked matrix ranged from 101.5% to 105.8%), sensitive (limit of detection ranged from 0.28 to 1.14 mg L-1) and precise (the relative standard deviations ranged from 0.13 to 2.8%). Inoscavin A and Hypholomine B were purified using high-speed counter-current chromatography (HSCCC), structural evaluated to meet the request of standard substances. UPLC separation was performed on a reversed-phase C18 column using gradient elution with acetonitrile and 0.1% formic acid over 10 min. The developed method was successfully applied to determine Inoscavin A and Hypholomine B in twelve Phellinus igniarius samples of different origins and the results showed that it was suitable for the analysis of these active components in Phellinus igniarius samples.

Quantitative assessment of photo- and bio-reactivity of chromophoric and fluorescent dissolved organic matter from biomass and soil leachates and from surface waters in a subtropical wetland

Dissolved organic matter (DOM) reactivity plays a central role in ecosystem function and the global carbon cycle. In this study, a suite of biomass and soil leachates together with surface water samples from the Florida coastal Everglades (FCE) were investigated to quantitatively assess the photo- and bio-reactivity of DOM via dissolved organic carbon (DOC), ultraviolet–visible absorbance (UV–Vis) measurements, and excitation-emission matrix (EEM) fluorescence combined with parallel factor analysis (PARAFAC). The decomposition patterns observed were diverse, but dominated by first order decay for most of the samples studied. The reactivity rate constants obtained based on a first order multi-pool kinetic model, suggest that the DOM in the Everglades is largely refractory on time scales relevant to this ecosystem (2 months). The relative reactivity of different fluorescent DOM pools determined as labile, semi-labile and refractory were in the order of biomass leachate > soil leachate > surface water. Photo-reactivity was found to be a more important process in controlling the fate of FDOM in this system, while FDOM was mainly refractory to bio-degradation. Degradation patterns and rate constants for samples of different origin displayed vast differences for the same PARAFAC component, suggesting a complex and heterogeneous composition of fluorophores for each component, most likely the result of different structures, speciation and conformation, and molecular weight distribution. In addition, a terrestrial humic-like and two protein-like components were found to have the potential to serve as indicators of photo-degradable and bioavailable DOM.

Validation data for the determination of perchlorate in water using ion chromatography with suppressed conductivity detection.

BackgroundPerchlorate salts are relatively stable, soluble in water, and migrate into groundwater sources. Groundwater is an essential source for drinking water suppliers. Perchlorate bears health risks as it is identified to impair normal thyroid function by interfering with iodine uptake by the thyroid gland. The development of a sensitive analytical method for the determination of perchlorate is therefore of the highest interest or public health. Ion chromatography is a sensitive method suitable for perchlorate determinations. This manuscript describes the validation of an ion chromatographic method. Perchlorate is determined by ion chromatography (IC) with conductivity detection after suppression (CD) applying isocratic elution.ResultsIn this study, the suitability of IC-CD was tested for synthetic samples, selected environmental water, drinking water, and swimming pool water in order to evaluate potential matrix effects on the perchlorate signal even after sample preparation. A sample injection volume of 750 μL was applied to the selected 2-mm-IC column. In untreated samples, the perchlorate peak can be interfered by neighbouring signals from matrix ions like chloride, nitrate, carbonate, and sulphate. Depending on the concentration of the matrix ions, the perchlorate peak can show asymmetric shape in particular when the perchlorate concentration is low. Recovery is reduced with increasing matrix ion concentrations. Dedicated matrix elimination was applied to minimize such effects. A reporting limit of 1.5 μg/L perchlorate and an expanded measurement uncertainty of 13.2 % were achieved.ConclusionThe extended method validation proves the applicability of IC based on the EPA 314.0 method for the determination of trace amounts of perchlorate in water samples of different origin. The results support the development of a respective international standard pursued by ISO. The approach evidenced its working robustness and ease of use in terms of eluent preparation, chromatographic resolution, column life time and sample preparation. Due to the simplified analytical workflow of the analytical procedure the application’s integration into the collection of methods of interested laboratories should be facilitated.