Chemical Composition Information Research Articles

Statistical Methods for Rapid Quantification of Proteins, Lipids, and Carbohydrates in Nordic Microalgal Species Using ATR-FTIR Spectroscopy.

Attenuated total reflection–Fourier transform infrared (ATR–FTIR) spectroscopy is a simple, cheap, and fast method to collect chemical compositional information from microalgae. However, (semi)quantitative evaluation of the collected data can be daunting. In this work, ATR–FTIR spectroscopy was used to monitor changes of protein, lipid, and carbohydrate content in seven green microalgae grown under nitrogen starvation. Three statistical methods—univariate linear regression analysis (ULRA), orthogonal partial least squares (OPLS), and multivariate curve resolution-alternating least squares (MCR–ALS)—were compared in their ability to model and predict the concentration of these compounds in the biomass. OPLS was found superior, since it i) included all three compounds simultaneously; ii) explained variations in the data very well; iii) had excellent prediction accuracy for proteins and lipids, and acceptable for carbohydrates; and iv) was able to discriminate samples based on cultivation stage and type of storage compounds accumulated in the cells. ULRA models worked well for the determination of proteins and lipids, but carbohydrates could only be estimated if already determined protein contents were used for scaling. Results obtained by MCR–ALS were similar to ULRA, however, this method is considerably easier to perform and interpret than the more abstract statistical/chemometric methods. FTIR-spectroscopy-based models allow high-throughput, cost-effective, and rapid estimation of biomass composition of green microalgae.

1D/2D MnWO4 nanorods anchored on g-C3N4 nanosheets for enhanced photocatalytic degradation ofloxacin under visible light irradiation

Herein, MnWO4 nanorods coupled with g-C3N4 nanosheets were fabricated by a simple hydrothermal method, followed by an ultrasonication method. Morphological features, chemical composition, optical properties and crystallographic information of the prepared materials were obtained using SEM-EDX, TEM, XRD, XPS, FT-IR, UV–vis DRS, and PL techniques. The synthesized MnWO4@g-C3N4 nanocomposite displayed excellent photocatalytic activity towards ofloxacin (OFX) under visible light irradiation. Moreover, the influence of reaction parameters such as the catalyst dosage, pollutant concentration and presence of inorganic anions (Cl−, CO32− and SO42−), was investigated during the photocatalytic process. Notably, among the inorganic anions, SO42− and CO32− significantly hampered OFX degradation, while Cl− ions showed minimal effect on the degradation process. The apparent rate constant for MnWO4@g-C3N4 from first order kinetics was 3.5 and 4.8 times higher than that of pure g-C3N4 and MnWO4, respectively. Based on the obtained results, the possible charge transfer mechanism was proposed. The enhanced photocatalytic performance of the binary nanocomposite could be ascribed to the synergistic effect between MnWO4 nanorods and g-C3N4 nanosheets resulting in efficient visible light utilization and inhibition of the charge carrier recombination. This work demonstrates the potential application of MnWO4@g-C3N4 nanostructures in the photocatalytic removal of emerging pollutants in water.

Chemical Composition and Nutritional Information of Fats Used in Fillings of Sandwich Cookies

AbstractThe aim of this work was to evaluate the characteristics of fillings used in cookies commercialized in Brazil and in USA according to their chemical composition, labels, nutritional information, ingredients list, and price. Fillings had approximately 25–32% of fat. In general, the composition of these fats consisted of approximately 50% of saturated fatty acids (SFA), mainly palmitic acid, and 50% of unsaturated fatty acids, mainly oleic acid. Brazilian samples had trans‐fatty acids (TFA) in the range of 1–15% although in many cases their presence was not reported in the labels. USA product labels did not present a fixed portion weight but they showed detailed information about the types of fats used such as source and the process used for their production. In 70% of Brazilian product labels, the information shown in the ingredient list was limited to “vegetable fat,” which does not give enough information to consumers about the type of fat used. In addition, our results showed that low‐trans‐products or zero‐trans‐products, in which TFA were replaced by SFA, presented the highest prices. This research suggests that further legislation should be developed in Brazil to decrease the amount of TFA in foods and improve their nutritional properties.

Amorphous Carbon Films In Situ Formed From PTFE Transfer Layer in Solid Lubricated Cryogenic Turbopump Bearings

In order to fully evaluate the service reliability of cryogenic turbopump bearings, a newly developed solid lubricated bearing was tested using a custom ground bearing test system cooled by water. Stains with different color intensity were occasionally exhibited on the surfaces of the bearing balls after ground tests. This may pose a risk for the reliable service of the related bearings in real flight missions. Then the chemical composition and structural information of the stain layers were systematically analyzed by x-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and high-resolution transmission electron microscope (HRTEM). The results manifested that the stain layer had the characteristic of α-C film. The color intensity of stains was not caused by the structural changes, but was due to the difference of stain layers’ thickness. The α-C films in situ formed during bearings operation should result from the defluorination of polytetrafluoroethylene (PTFE) layers, which transferred from retainer to balls in the previous step. Correspondingly, FeF2 was produced on the surfaces of the tested bearing rings as a by-product. Although the tested bearings with α-C films formed on the surfaces of balls did not reach the state of final failure, the affected balls showed high surface roughness, which could be an indicator of an imminent bearing failure.

Insights into the O : C-dependent mechanisms controlling the evaporation of α-pinene secondary organic aerosol particles

Abstract. The volatility of oxidation products of volatile organic compounds (VOCs) in the atmosphere is a key factor to determine if they partition into the particle phase contributing to secondary organic aerosol (SOA) mass. Thus, linking volatility and measured particle composition will provide insights into SOA formation and its fate in the atmosphere. We produced α-pinene SOA with three different oxidation levels (characterized by average oxygen-to-carbon ratio; O:C‾=0.53, 0.69, and 0.96) in an oxidation flow reactor. We investigated the particle volatility by isothermal evaporation in clean air as a function of relative humidity (RH <2 %, 40 %, and 80 %) and used a filter-based thermal desorption method to gain volatility and chemical composition information. We observed reduced particle evaporation for particles with increasing O:C‾ ratio, indicating that particles become more resilient to evaporation with oxidative aging. Particle evaporation was increased in the presence of water vapour and presumably particulate water; at the same time the resistance of the residual particles to thermal desorption was increased as well. For SOA with O:C‾=0.96, the unexpectedly large increase in mean thermal desorption temperature and changes in the thermogram shapes under wet conditions (80 % RH) were an indication of aqueous phase chemistry. For the lower O:C‾ cases, some water-induced composition changes were observed. However, the enhanced evaporation under wet conditions could be explained by the reduction in particle viscosity from the semi-solid to liquid-like range, and the observed higher desorption temperature of the residual particles is a direct consequence of the increased removal of high-volatility and the continued presence of low-volatility compounds.

Assessing the effect of ingredients variability on the composition of the final complete feed for swine

To characterize the variability of 11 feed ingredients and their impact on the final feed, 728 ingredient samples were collected during 5 months in a feed-plant and were analyzed by near-infrared spectrophotometry (NIRS). Six diets for fattening pigs and gestating sows were formulated using regional information of ingredient chemical composition (reference): LIM, limited; EU, common European; and MULT, multi-ingredient; respectively, including 5, 7, and 10 ingredients. The formulas were replicated 15 times using actual chemical composition (NIRS) from three samples per ingredient and month. This theoretical procedure was validated through small-scale manufacturing 30 LIM-diets, which samples were proximal (PA) and NIRS analyzed for dry matter and crude protein (CP) contents. Those mixtures were also PA analyzed. The ingredients showed coefficient of variation (CV %) higher for crude fiber (CF) (2.6%–18.3%) than CP (2.0%–9.3%). Comparing all diets for all chemical components, variability was reduced when including more ingredients from 0.5%–5.5% to 0.3%–2.6% CV. In most cases, the actual chemical composition of the diets underestimated their reference formula (1.3%–10.8%, CP and CF). A deviation from the targeted diet occurs if variability is not regarded. Therefore, a proper method to predict ingredient composition and nutritional value before use may increase the accuracy of diet formulation between 2% and 10%.

How to integrate wet lab and bioinformatics procedures for wine DNA admixture analysis and compositional profiling: Case studies and perspectives.

The varietal authentication of wines is fundamental for assessing wine quality, and it is part of its compositional profiling. The availability of historical, cultural and chemical composition information is extremely important for quality evaluation. DNA-based techniques are a powerful tool for proving the varietal composition of a wine. SSR-amplification of genomic residual Vitis vinifera DNA, namely Wine DNA Fingerprinting (WDF) is able to produce strong, analytical evidence concerning the monovarietal nature of a wine, and for blended wines by generating the probability of the presence/absence of a certain variety, all in association with a dedicated bioinformatics elaboration of genotypes associated with possible varietal candidates. Together with WDF we could exploit Bioinformatics techniques, due to the number of grape genomes grown. In this paper, the use of WDF and the development of a bioinformatics tool for allelic data validation, retrieved from the amplification of 7 to 10 SSRs markers in the Vitis vinifera genome, are reported. The wines were chosen based on increasing complexity; from monovarietal, experimental ones, to commercial monovarietals, to blended commercial wines. The results demonstrate that WDF, after calculation of different distance matrices and Neighbor-Joining input data, followed by Principal Component Analysis (PCA) can effectively describe the varietal nature of wines. In the unknown blended wines the WDF profiles were compared to possible varietal candidates (Merlot, Pinot Noir, Cabernet Sauvignon and Zinfandel), and the output graphs show the most probable varieties used in the blend as closeness to the tested wine. This pioneering work should be meant as to favor in perspective the multidisciplinary building-up of on-line databanks and bioinformatics toolkits on wine. The paper concludes with a discussion on an integrated decision support system based on bioinformatics, chemistry and cultural data to assess wine quality.

Online coupling of thermal field-flow fractionation and Fourier transform infrared spectroscopy as a powerful tool for polymer characterization

The rapid growth and increasing importance of complex polymers has accelerated the need for advancement in characterization techniques. The analysis of such materials is challenging and the determination of different molecular parameters requires the combination of different advanced analytical techniques. Preferably, coupled and hyphenated techniques are used that provide different molecular parameters simultaneously in one experiment.Complementary to column-based fractionation techniques, channel-based methods such as thermal field-flow fractionation (ThFFF) are attractive as they can address different molecular parameters for a variety of analytes ranging from single macromolecules to macromolecular assemblies and nanoparticles. In the past, ThFFF has been coupled to a variety of size (molar mass) sensitive detectors such as multiangle laser light scattering and dynamic light scattering. Now, for the first time, the online coupling of ThFFF to Fourier transform infrared (FTIR) spectroscopy is presented. Different from standard single- or dual-wavelength IR detectors, this detector provides full spectra over the complete mid infrared range that can be used for concentration detection as well as chemical composition information. The applicability of online multidetector ThFFF-FTIR is demonstrated for selected polymer blends and copolymers comprising styrene and methyl methacrylate.

Metabolism and spatial distribution of metalaxyl in tomato plants grown under hydroponic conditions

Knowledge about translocation of plant protection products (PPP's) in plants is important to understand the uptake via the root system. Here we report the combination of analysis of tissue extracts by LC-HRMSn, autoradiography of 14C-labeled compounds and MALDI-MSI, which combine qualitative and quantitative information of chemical composition and the spatial distribution of PPP's and their metabolites in situ. Therefore, the uptake of the phenylamide fungicide metalaxyl was studied in tomato plants (Solanum lycopersicum) using a hydroponic system. The plants have been cultivated in perlite until the two-leaf stage and were transferred into the hydroponic test system afterwards. The radioactive labeled fungicide was readily taken up by the roots during the normal water consumption and radioactivity was translocated uniformly to the aboveground part of the tomato plants, while only small proportion of the applied radioactivity were observed in the roots. The distribution of metalaxyl after the plant uptake experiment in the primary roots where analyzed by a transversal tissue section in the zone of maturation. Metalaxyl is mainly localized in root xylem and in cortex located at the epidermis. With LC-HRMSn and radiochemical analyses of stem and leaf, no parent compound was detectable. Four polar metabolites were the main identified components of the residue and could be visualized by MALDI-imaging mass spectrometry. With these results we could show, that the fungicide metalaxyl is taken up by the plant via the roots during the regular water consumption and transported to xylem.

Self-Powered All-in-One Fluid Sensor Textile with Enhanced Triboelectric Effect on All-Immersed Dendritic Liquid-Solid Interface.

Enormous interests have been attracted on exploiting interfacial triboelectric effects for sensor and energy applications but immensely limited by the inefficient liquid-solid electrification in terms of immersed applications in fluid. Here, we have presented a flexible self-powered all-in-one fluid sensor textile, for simultaneously monitoring the velocity, acceleration, and chemical composition based on an enhanced liquid-solid triboelectric effect. The textile was woven from flexible dendritic cable electrodes surrounded by arrays of micrometal dendrites, which could be further coated with a layer of polytetrafluoroethylene nanofibers. Even when completely immersed in the fluid, the textile can efficiently output a combined electric signal for parsing the velocity, acceleration, and chemical composition information. Furthermore, a textile of 6 cm2 can charge a commercialized capacitor to 1 V within 80 s by harvesting flow energy on the liquid/solid interface, showing a potential use as the power supply of a signal-processing circuit. It has proposed a promising fluid sensor without extra power cables, for alerting possible leakage or blockage inside chemical and petroleum pipelines.

Impact of urban aerosol properties on cloud condensation nuclei (CCN) activity during the KORUS-AQ field campaign

Ground measurements of physical, chemical and hygroscopic properties of aerosols were made at the Olympic Park, Seoul, as part of the KORea-United States Air Quality study (KORUS-AQ) campaign in May–June 2016. The average number concentrations of aerosols larger than 10 nm in diameter and cloud condensation nuclei (CCN) at 0.6% supersaturation (S) were 10800 cm−3 and 3400 cm−3, respectively. The average geometric mean diameter (Dg) was 44 nm, and size-resolved aerosol hygroscopicity (κ) from HTDMA ranged from 0.11 to 0.24 for particle diameters in the range of 30–150 nm. Aerosols were classified into three types based on mixing state and hygroscopic growth factor (GF): Type 1 (externally mixed aerosol), Type 2 (Internally mixed and growth aerosol) and Type 3 (internally mixed and non-growth aerosol). These three aerosol types showed distinct diurnal patterns. The difference in physical and chemical properties of aerosols for different air mass sources crucially impacted aerosol hygroscopicity. Using the external mixture assumption with measured hygroscopicity data improved the results of CCN prediction compared to those from the simple internal mixture assumption because externally mixed aerosols comprised a significant portion of aerosols in this urban area. Moreover, the simple assumption of aerosol size distribution with a fixed chemical composition sufficiently explained more than 50 percent of the variation of CCN number concentrations, although the information of chemical composition was still meaningful. Overall, the measured data showed consistency with Megacity Air Pollution Studies (MAPS-Seoul) campaign held during May–June 2015, implying that these results may represent urban aerosols in spring/summer in the Korean Peninsula.

Meat Quality of Rainbow Trout (Oncorhynchus Mykiss) from the Bistrișorii Valley Trout Farm, Alba County

Fish meat represents a great energy source in human nutrition, due to its content in high biological value protein, lipids which contain omega acids and minerals. The chemical composition of fish meat can be influenced by several factors such as: species, administered feed, environment, age and spawning period. The aim of this research was to analyse the chemical composition of the rainbow trout meat reared in the fishery Valea Bistrişorii, in a classical system. The determination of water (W %), minerals (M %) and dry matter (DM %) content was performed by calcination. The crude fat (CF %) was determined by Soxhlet method and crude protein (CP %) by the Kjeldahl method. Analysing the chemical composition of the rainbow trout meat, the following values were obtained: W = 73.60 ± 0.23%; DM = 26.40 ± 0.14%; CP = 18.21 ± 0.14%; CF = 6.87%; M = 1.32%.The obtained data offers useful information of meat chemical composition for selection of future breeders and improving the rainbow troutraised in the Bistrişorii Valley.

(Invited) One Step Synthesis of Li-Alkyl Carbonates and Their Applications As Coatings on Li Anode

Lithium metal is being extensively studied as an anode to replace graphite due to its high capacity and the lowest negative electrochemical potential.1 Current research focus is to mitigate lithium dendrite growth and to increase coulomb efficiency during electrochemical cycling by using various surface coatings or electrolyte additives. Due to the complex reduction reactions of electrolyte components on lithium metal surface, it is highly desirable to develop coating materials with high electrochemical stability. In this work, we report the synthesis of several Li-alkyl carbonates via a simple one step reaction. These carbonates are known components of solid electrolyte interface (SEI) layers on lithium and graphite anode surfaces. The chemical composition and structural information of these synthetic Li-alkyl carbonates are identified by X-ray diffraction and Infrared Spectroscopy. In one implementation of the reaction, a single-component coating is formed on Li metal in a LiI/organic carbonates (dimethyl carbonate (DMC) and ethylene carbonate (EC)) electrolyte. LiI chemically reacts with dimethyl carbonate to form lithium methyl carbonate, which precipitates and forms a chemically homogeneous coating layer on Li surface. This coating layer is shown to enable dendrite free Li cycling in a symmetric Li||Li cell even at a current density of 3 mA cm-2. Adding EC to DMC modulates the formation of the lithium methyl carbonate, resulting in a stable coating layer which is essential for long term Li cycling stability. Fig.1 shows the morphology of deposited Li using LiI-EC/DMC electrolytes.2 Furthermore, the coating can enable dendrite free, high coulomb efficiency cycling after being transferred to common LiPF6/carbonates electrolytes which are compatible with metal oxide cathodes. We will show that LiI reacts with a broad range of organic carbonates and ethers to form lithium compounds relevant to high efficiency operations of battery anodes. Acknowledgements This work was supported by the Office of Vehicle Technologies of the U.S. Department of Energy through the Advanced Battery Materials Research Program (Battery 500 Consortium) under Contract DE-EE0007764. Reference W. Xu, J. L. Wang, F. Ding, X. L. Chen, E. Nasybutin, Y. H. Zhang and J. G. Zhang, Energ Environ Sci, 2014, 7, 513-537.H. D. Liu, H. Y. Zhou, B. S. Lee, X. Xing, M. Gonzalez and P. Liu, ACS Appl Mater Inter, 2017, 9, 30635-30642. Figure 1

Impact of Sampling and Cellular Separation on Amino Acid Determinations in Drosophila Hemolymph.

The fruit fly is a frequently used model system with a high degree of human disease-related genetic homology. The quantitative chemical analysis of fruit fly tissues and hemolymph uniquely brings chemical signaling and compositional information to fly experimentation. The work here explores the impact of measured chemical content of hemolymph with three aspects of sample collection and preparation. Cellular content of hemolymph was quantitated and removed to determine hemolymph composition changes for seven primary amine analytes. Hemolymph sampling methods were adapted to determine differences in primary amine composition of hemolymph collected from the head, antenna, and abdomen. Also, three types of anesthesia were employed with hemolymph collection to quantitate effects on measured amino acid content. Cell content was found to be 45.4 ± 22.1 cells/nL of hemolymph collected from both adult and larvae flies. Cell-concentrated fractions of adult, but not larvae, hemolymph were found to have higher and more variable amine content. There were amino acid content differences found between all three areas indicating a robust method to characterize chemical markers from specific regions of a fly, and these appear related to physiological activity. Methods of anesthesia have an impact on hemolymph amino acid composition related to overall physiological impact to fly including higher amino acid content variability and oxygen deprivation effects. Together, these analyses identify potential complications with Drosophila hemolymph analysis and opportunities for future studies to relate hemolymph content with model physiological activity.

Physically corrected forward operators for induced emission tomography: a simulation study

X-ray emission tomography techniques over non-radioactive materials allow one to investigate different and important aspects of the matter that are usually not addressable with the standard x-ray transmission tomography, such as density, chemical composition and crystallographic information. However, the quantitative reconstruction of these investigated properties is hindered by additional problems, including the self-attenuation of the emitted radiation.Work has been done in the past, especially concerning x-ray fluorescence tomography, but this has always focused on solving very specific problems. The novelty of this work resides in addressing the problem of induced emission tomography from a much wider perspective, introducing a unified discrete representation that can be used to modify existing algorithms to reconstruct the data of the different types of experiments.The direct outcome is a clear and easy mathematical description of the implementation details of such algorithms, despite small differences in geometry and other practical aspects, but also the possibility to express the reconstruction as a minimization problem, allowing the use of variational methods, and a more flexible modeling of the noise involved in the detection process.In addition, we look at the results of a few selected simulated data reconstructions that describe the effect of physical corrections like the self-attenuation, and the response to noise of the adapted reconstruction algorithms.

Discrimination of Radix Polygoni Multiflori from different geographical areas by UPLC-QTOF/MS combined with chemometrics

BackgroundNowadays, Radix Polygoni Multiflori (RPM, Heshouwu in Chinese) from different geographical origins were used in clinic. In order to characterize the chemical profiles of different geographical origins of RPM samples, ultra-high performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-QTOF/MS) combined with chemometrics (partial least squared discriminant analysis, PLS‑DA) method was applied in the present study.MethodsThe chromatography, chemical composition and MS information of RPM samples from 18 geographical origins were acquired and profiled by UPLC-QTOF/MS. The chemical markers contributing the differentiation of RPM samples were observed and characterized by supervised PLS‑DA method of chemometrics.ResultsThe chemical composition differences of RPM samples derived from 18 different geographical origins were observed. Nine chemical markers were tentatively identified which could be used as specific chemical markers for the differentiation of geographical RPM samples.ConclusionsUPLC-QTOF/MS method coupled with chemometrics analysis has potential to be used for discriminating different geographical TCMs. Results will help to develop strategies for conservation and utilization of RPM samples.

Grouping concept for metal and metal oxide nanomaterials with regard to their ecotoxicological effects on algae, daphnids and fish embryos

Manufactured nanomaterials (NMs) are being developed in many different variations such as size, shape, crystalline structure and surface modifications. To avoid the testing of each single nanomaterial variation, grouping and read-across strategies for nanomaterials similar to classical chemicals are discussed. Grouping and read-across aim to identify NM groups with analogous sets of properties or properties that enable reasonable predictions of a NM hazard without additional testing. This will contribute to save costs and time in the risk assessment. So far the knowledge is still limited how modifications of NMs and their properties affect ecotoxicity.This study was initiated to support the discussions on grouping regarding aquatic ecotoxicological effects and for the identification of relevant properties as well as the development of a grouping concept addressing aquatic ecotoxicity. A comprehensive and homogenous data set based on fourteen nanomaterials was established. The selected NMs were modifications of five chemical species (Ag, ZnO, TiO2, CeO2, Cu). As the focus was on the applicability for regulatory purposes, for ecotoxicity the OECD test guidelines 201 (algae), 202 (daphnids) and 236 (fish embryo) were considered. The physico-chemical properties of the chosen NMs were determined in deionized water and the test media applied for the ecotoxicological tests. Reactivity, ion release, morphology and ecotoxicity of the chemical composition (information from the bulk material) were identified as the most relevant grouping properties regarding nanomaterial's ecotoxicity. A grouping scheme and procedure was proposed considering these properties. The scheme was validated with a set of additional nanomaterials (TiO2, SiO2, Fe2O3).A rough, but reliable grouping of NMs with different chemical composition was possible. The separation of NMs with the same chemical composition, into different groups was only feasible, if the NMs show major differences in one of the relevant properties (e.g. different shape). Based on the available data set it is unknown whether either further physico-chemical properties have to be considered or whether the impact of the selected variations on ecotoxicity is too minor to result in significant ecotoxicological differences. In order to further advance the grouping concept for regulatory testing, future developments should include the specification of threshold values with regard to the properties solubility and reactivity as well as for the characterization of the morphology. Additionally, test methods addressing the sorption tendency of NMs to algae could contribute to an improvement of the ecotox-scheme with regard to the consideration of physical effects by shading resulting in limited growth.

Enhanced EDX images by fusion of multimodal SEM images using pansharpening techniques.

The goal of this paper is to explore the potential interest of image fusion in the context of multimodal scanning electron microscope (SEM) imaging. In particular, we aim at merging the backscattered electron images that usually have a high spatial resolution but do not provide enough discriminative information to physically classify the nature of the sample, with energy-dispersive X-ray spectroscopy (EDX) images that have discriminative information but a lower spatial resolution. The produced images are named enhanced EDX. To achieve this goal, we have compared the results obtained with classical pansharpening techniques for image fusion with an original approach tailored for multimodal SEM fusion of information. Quantitative assessment is obtained by means of two SEM images and a simulated dataset produced by a software based on PENELOPE.

Application of TXRF and XRPD techniques for analysis of elemental and chemical composition of human kidney stones

Total reflection X‐ray fluorescence analysis and X‐ray powder diffraction were used for elemental and chemical composition analysis of 83 samples of human kidney stones. Samples came from patients after surgical removal of stones. Elements such as P, K, Ca, Fe, Zn, Ni, Br, Sr, and Pb were determined in all samples. Other elements Mg, S, Cl, Ti, V, Cr, Mn, Cu, Se, Rb, I, and Bi were found in some of the analyzed kidney stones (censoring effect). Descriptive statistics were calculated for all elements paying particular attention to the censored elements. From diffraction measurements, the following crystalline substances were determined in the stones: apatite, struvite, uric acid, weddellite, whewellite, magnesium phosphate, and calcium phosphate. Information of chemical composition was applied to classify the analyzed kidney stone into four groups. Statistical analysis of the results included multigroups comparison, testing of element concentration distribution, and elemental correlations in the dependence of kind of kidney stones. The presented studies are part of wider microbiological studies focusing on the correlation between different kinds of bacteria and fungi presented in the samples of kidney stones and their elemental as well as chemical composition. Information on stone composition can be helpful in understanding kidney stone formation and complemented by additional metabolic blood and urine tests. This, in turn, can lead to appropriate medical treatment together with the reduction of the risk as regards forming new stones.

Hyperspectral imaging detection of decayed honey peaches based on their chlorophyll content

Honey peach is a very common but highly perishable market fruit. When pathogens infect fruit, chlorophyll as one of the important components related to fruit quality, decreased significantly. Here, the feasibility of hyperspectral imaging to determine the chlorophyll content thus distinguishing diseased peaches was investigated. Three optimal wavelengths (617nm, 675nm, and 818nm) were selected according to chlorophyll content via successive projections algorithm. Partial least square regression models were established to determine chlorophyll content. Three band ratios were obtained using these optimal wavelengths, which improved spatial details, but also integrates the information of chemical composition from spectral characteristics. The band ratio values were suitable to classify the diseased peaches with 98.75% accuracy and clearly show the spatial distribution of diseased parts. This study provides a new perspective for the selection of optimal wavelengths of hyperspectral imaging via chlorophyll content, thus enabling the detection of fungal diseases in peaches.