Low-cost Quality Control Research Articles

All-in-one 2LabsToGo system for analysis of ergot alkaloids in whole rye

Ergot alkaloids, naturally occurring mycotoxins of Claviceps fungi, pose health risks. This necessitates accurate analysis methods to ensure food safety. This study explored the open-source miniaturized all-in-one 2LabsToGo system to analyze ergot alkaloids in whole rye samples. It is suited for sustainable atline analysis as it combines all planar chromatography tasks, allowing low-cost quality control in milling plants. The LOD and LOQ of ergocristine were determined to be 0.4 and 1.2 ng/zone, respectively. Detectability of ergot alkaloids was proven to be below the current maximum limit of 500 µg/kg for rye milling products. The repeatability (%RSD) was 4.1 % and the coefficient of determination of the analytical response (R2) was 0.9918 for ergocristine. The mean recovery rate of ergot alkaloids in spiked whole rye grain was close to 100 %. Results of screening whole rye for ergot alkaloids were successfully verified by comparison with those obtained by conventional status quo HPTLC instrumentation.

Quality Testing in Aluminum Die-Casting – A Novel Approach using Acoustic Data in Neural Networks

In quality control of aluminum die casting various processes are used. For example, the density of the parts can be measured, X-ray images or images from the computed tomography are analyzed. All common processes lead to practically usable results. However, the problem arises that none of the processes is suitable for inline quality control due to their time duration and to their costs of hardware. Therefore, a concept for a fast and low-cost quality control process using sound samples is presented here. Sound samples of 240 aluminum castings are recorded and checked for their quality using X-ray images. All parts are divided into the categories "good" without defects, "medium" with air inclusions ("blowholes") and "poor" with cold flow marks. For the processing of the generated sound samples, a Convolutional Neuronal Network was developed. The training of the neural network was performed with both complete and segmented sound samples ("windowing"). The generated models have been evaluated with a test data set consisting of 120 sound samples. The results are very promising. Both models show an accuracy of 95% and 87% percent, respectively. The results show that a new process of acoustic quality control can be realized using a neural network. The model classifies most of the aluminum castings into the correct categories. Keywords: acoustic quality control, aluminum die casting, convolutional neural networks, sound data

Investigation of Spectroscopic Peculiarities of Ergot-Infected Winter Wheat Grains.

Wheat has played an important role in human agriculture since ancient times. Increasing rates of processed wheat product fabrication require more and more laboratory studies of product quality. This, in turn, requires the use, in production and in field conditions, of sufficiently accurate, fast and relatively low-cost quality control methods, including the detection of fungal diseases. One of the most widespread fungal diseases of wheat in the world is ergot caused by the fungi genus Claviceps. Optical methods are promising for this disease identification due to the relative ease of implementation and the possibility of performing fast analyses in large volumes. However, for application in practice, it is necessary to identify and substantiate characteristic spectral markers that make it possible to judge the sample contamination. In this regard, within the framework of this study, the methods of IR absorption spectroscopy in the MIR region and reflection spectroscopy in the UV-vis-NIR ranges, as well as luminescence spectroscopy, were used to study ergot-infected grains of winter wheat of the "Moskovskaya 56" cultivar. To justify the choice of the most specific spectral ranges, the methods of chemometric analysis with supervised classification, namely PCA-LDA and PCA-SVM, were applied. The possibility of separating infected grains according to the IR absorption, reflection spectra in the UV-vis-NIR ranges and visible luminescence spectra was tested.

Development of species diagnostic SNP markers for quality control genotyping in four rice (Oryza L.) species

Species misclassification (misidentification) and handling errors have been frequently reported in various plant species conserved at diverse gene banks, which could restrict use of germplasm for correct purpose. The objectives of the present study were to (i) determine the extent of genotyping error (reproducibility) on DArTseq-based single-nucleotide polymorphisms (SNPs); (ii) determine the proportion of misclassified accessions across 3134 samples representing three African rice species complex (Oryza glaberrima, O. barthii, and O. longistaminata) and an Asian rice (O. sativa), which are conserved at the AfricaRice gene bank; and (iii) develop species- and sub-species (ecotype)-specific diagnostic SNP markers for rapid and low-cost quality control (QC) analysis. Genotyping error estimated from 15 accessions, each replicated from 2 to 16 times, varied from 0.2 to 3.1%, with an overall average of 0.8%. Using a total of 3134 accessions genotyped with 31,739 SNPs, the proportion of misclassified samples was 3.1% (97 of the 3134 accessions). Excluding the 97 misclassified accessions, we identified a total of 332 diagnostic SNPs that clearly discriminated the three indigenous African species complex from Asian rice (156 SNPs), O. longistaminata accessions from both O. barthii and O. glaberrima (131 SNPs), and O. sativa spp. indica from O. sativa spp. japonica (45 SNPs). Using chromosomal position, minor allele frequency, and polymorphic information content as selection criteria, we recommended a subset of 24 to 36 of the 332 diagnostic SNPs for routine QC genotyping, which would be highly useful in determining the genetic identity of each species and correct human errors during routine gene bank operations.

Integrative two-dimensional correlation spectroscopy (i2DCOS) for the intuitive identification of adulterated herbal materials

IR, Raman and other separation-free and label-free spectroscopic techniques have been the promising methods for the rapid and low-cost quality control of complex mixtures such as food and herb. However, as the overlapped signals from different ingredients usually make it difficult to extract useful information, chemometrics tools are often needed to find out spectral features of interest. With designed perturbations, two-dimensional correlation spectroscopy (2DCOS) is a powerful technique to resolve the overlapped spectral bands and enhance the apparent spectral resolution. In this research, the integrative two-dimensional correlation spectroscopy (i2DCOS) is defined for the first time overcome some disadvantages of synchronous and asynchronous correlation spectra for identification. The integrative 2D correlation spectra weight the asynchronous cross peaks by the corresponding synchronous cross peaks, which combines the signal-to-noise ratio advantage of synchronous correlation spectra and the spectral resolution advantage of asynchronous correlation spectra. The feasibility of the integrative 2D correlation spectra for the quality control of complex mixtures is examined by the identification of adulterated Fritillariae Bulbus powders. Compared with model-based pattern recognition and multivariate calibration methods, i2DCOS can provide intuitive identification results but not require the number of samples. The results show the potential of i2DCOS in the intuitive quality control of herbs and other complex mixtures, especially when the number of samples is not large.

Use of RGB digital video analysis to study electrochemical processes involving color changes

Color changes on an electrode surface during the course of electrochemical processes were monitored by in situ digital video recording. The evolution of standard red, green and blue (sRGB) intensity channels extracted from digital images showed a close relationship with the electrochemical processes taking place. In particular, the derivative of the sRGB mean intensity with respect to time (dI−/dt) gave useful insights into the electrochemical mechanism. The standard deviation (std) of the sRGB intensity provided information about the color homogeneity of the studied region on the electrode surface. We selected poly(o-toluidine) electrochromism on a transparent electrode and anodic copper dissolution on an opaque electrode as examples. Independently of electrode transparency and area, we were able to separate electrochromic processes, to monitor fast electrochromic changes and to evaluate the spatial distribution of metal dissolution on a composite electrode. These results show great promise for use in innovative investigations and for fast, low-cost quality control of electrochromic devices or modified electrodes.

The 2016 Joseph W. Richards Summer Research Fellowship — Summary Report: Single Drop Electroanalysis for Low Cost Quality Control Testing of Oxidative Pharmaceuticals

The 2016 Joseph W. Richards Summer Research Fellowship — Summary Report: Single Drop Electroanalysis for Low Cost Quality Control Testing of Oxidative Pharmaceuticals

중소규모 SW개발 프로젝트를 위한 시각화 기반의 Tool-Chain 품질관리 방법 제안

Since the concept of software engineering was first used in 1968 by NATO Science Committee, a lot of research work and improvements have been made on software development methodology and software quality control, but they still fall short of ensuring successful development of small and medium scale software systems. Under these circumstances, Center for Software Engineering (CSE) at National IT Industry Promotion Agency(NIPA) has been conducting studies on quality control methodologies of software visualization well-suited for small and medium scale software systems, and also working on the systemization and quantification of software quality control. In this paper, we attempt to scope on the software development management of domestic and foreign small and medium-sized enterprises that are lying in the blind spot, compared to large enterprises with well-organized software development systems. In particular, based on software visualization that CSE is pursuing for small and medium-sized developers, we propose a practical quality control methodology well-suited for small and medium scale projects, and a low-cost quality control management tool by combining open-source quality control tools. Our proposal is expected to induce developers` mind change in SI-specialized small and medium-sized software enterprises, increase their profits and improve customer satisfaction through project quality control.

A simple and rapid spectrofluorimetric method for the determination of testosterone in biological fluids

Testosterone is a representative natural steroid hormone with potent androgenic and anabolic properties and consequently used by youngsters and athletes to achieve bodies with lean muscle mass, improve skin elasticity as well as increase endurance and tolerance to strenuous exercise. The long-term use of marketed preparations containing testosterone can result in latent health risks to consumers. There are genuine demands for continuous development of highly sensitive and effective quantification methods for analytically monitoring the illegal use of testosterone. Previously existing methods like HPLC-UV, HPLC-MS and GC-MS are time consuming as well as tedious operation procedures limit their use. Hence a simple, precise, accurate, sensitive and reliable method for determination of low concentrations of testosterone in biological fluids viz., serum has been developed. The developed spectrofluorimetric method provides a faster and low cost quality control by simultaneous routine analysis of testosterone in biological fluids as well as marketed preparations containing testosterone.

Development of caprine liver quality control materials for trace element analysis of biological tissues

Certified reference materials (CRMs) are used in analytical chemistry for method validation studies in order to establish measurement accuracy, traceability, and long-term stability throughout repeated analyses. Quality control (QC) during routine analysis requires access to stable materials appropriate for the sample matrix being analyzed. However, it may be difficult to find representative, low-cost QC materials, especially for specific analytes in biological tissue matrices. Here, four caprine liver pools are prepared for use as internal QC materials for trace element measurements in biological tissue. Analytes of interest include essential and nonessential trace elements and the lanthanide series elements. The suitability of caprine liver to serve as a secondary reference material (RM), as well as for routine QC purposes, is demonstrated through homogeneity and stability measurements, and the acquisition of precision and uncertainty data. Traceability is established for selected analytes for which available CRMs can provide an unbroken chain of calibrations.

Fluorescence microscopy for quality control in nanoimprint lithography

Fluorescence microscopy is introduced as a low cost quality control process for nanoimprint lithography. To depict imprinted structures down to 1 μm lateral size and to detect residues down to 100 nm lateral size, the standard printable polymer mr-I8000 is labelled with less than 0.1 wt.% fluorescent dye. Three different types of stamps are used to determine the dependence of the shape and size of stamp features in a series of imprints. The quality of a stamp is given by the sticking polymer residues per unit area. Fluorescence light images as well as visible light images are analysed. Changes in the area of the stamp covered with polymer as a function of the number of imprints is summarised in a statistical process chart. Adhesion was artificially induced in order to observe self cleaning of virgin stamps. They were detected and monitored, suggesting that this method is a suitable technique for quality control and that it could be easily adapted to the nanoimprint process.