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2022 ◽  
Vol 14 (2) ◽  
pp. 319
Author(s):  
Tanzeel U. Rehman ◽  
Libo Zhang ◽  
Dongdong Ma ◽  
Jian Jin

Hyperspectral imaging has increasingly been used in high-throughput plant phenotyping systems. Rapid advancement in the field of phenotyping has resulted in a wide array of hyperspectral imaging systems. However, sharing the plant feature prediction models between different phenotyping facilities becomes challenging due to the differences in imaging environments and imaging sensors. Calibration transfer between imaging facilities is crucially important to cope with such changes. Spectral space adjustment methods including direct standardization (DS), its variants (PDS, DPDS) and spectral scale transformation (SST) require the standard samples to be imaged in different facilities. However, in real-world scenarios, imaging the standard samples is practically unattractive. Therefore, in this study, we presented three methods (TCA, c-PCA, and di-PLSR) to transfer the calibration models without requiring the standard samples. In order to compare the performance of proposed approaches, maize plants were imaged in two greenhouse-based HTPP systems using two pushbroom-style hyperspectral cameras covering the visible near-infrared range. We tested the proposed methods to transfer nitrogen content (N) and relative water content (RWC) calibration models. The results showed that prediction R2 increased by up to 14.50% and 42.20%, while the reduction in RMSEv was up to 74.49% and 76.72% for RWC and N, respectively. The di-PLSR achieved the best results for almost all the datasets included in this study, with TCA being second. The performance of c-PCA was not at par with the di-PLSR and TCA. Our results showed that the di-PLSR helped to recover the performance of RWC, and N models plummeted due to the differences originating from new imaging systems (sensor type, spectrograph, lens system, spatial resolution, spectral resolution, field of view, bit-depth, frame rate, and exposure time) or lighting conditions. The proposed approaches can alleviate the requirement of developing a new calibration model for a new phenotyping facility or to resort to the spectral space adjustment using the standard samples.


2021 ◽  
Vol 23 (6) ◽  
pp. 439-444
Author(s):  
Manar Nesser ◽  
Olivier Maloberti ◽  
Elias Salloum ◽  
Julien Dupuy ◽  
Jérôme Fortin

Improving the performance of electrical steels within the magnetic circuits is essential to save energy. The domain refinement through local surface treatment by laser is an effective technique to reduce the iron losses in grain-oriented iron silicon steels. To interpret the mechanism of this technique, we have quantitatively studied the impact of nanosecond pulse laser treatment on the magnetic properties of grain-oriented Fe(3%wt)Si sheets. We measured the total power loss and apparent permeability of the samples using a Single-Sheet Tester (SST). The laser treatment resulted in a loss reduction of up to 24% compared to the average power loss of standard samples at 50 Hz. At mid-induction levels, the reduction was also accompanied by an improvement in apparent permeability. A dynamic magnetic behavior law was used to identify a dynamic property Λ including information on density, surface area and wall mobility and another internal permeability property µ representative of static field and magnetization characteristics. Lastly, we presented the behavior of these properties under different laser treatment.


Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 138
Author(s):  
Celia Dolçà ◽  
Eduardo Fages ◽  
Eloi Gonga ◽  
David Garcia-Sanoguera ◽  
Rafael Balart ◽  
...  

Biobased HDPE (bioHDPE) was melt-compounded with different percentages (2.5 to 40.0 wt.%) of short hemp fibers (HF) as a natural reinforcement to obtain environmentally friendly wood plastic composites (WPC). These WPC were melt-compounded using a twin-screw extrusion and shaped into standard samples by injection molding. To improve the poor compatibility between the high non-polar BioHDPE matrix and the highly hydrophilic lignocellulosic fibers, a malleated copolymer, namely, polyethylene-graft-maleic anhydride (PE-g-MA), was used. The addition of short hemp fibers provided a remarkable increase in the stiffness that, in combination with PE-g-MA, led to good mechanical performance. In particular, 40 wt.% HF drastically increased the Young’s modulus and impact strength of BioHDPE, reaching values of 5275 MPa and 3.6 kJ/m2, respectively, which are very interesting values compared to neat bioHDPE of 826 MPa and 2.0 kJ/m2. These results were corroborated by dynamic mechanical thermal analysis (DMTA) results, which revealed a clear increasing tendency on stiffness with increasing the fiber loading over the whole temperature range. The crystal structure was not altered by the introduction of the natural fibers as could be seen in the XRD patterns in which mainly the heights of the main peaks changed, and only small peaks associated with the presence of the fiber appeared. Analysis of the thermal properties of the composites showed that no differences in melting temperature occurred and the non-isothermal crystallization process was satisfactorily described from the combined Avrami and Ozawa model. As for the thermal degradation, the introduction of HF resulted in the polymer degradation taking place at a higher temperature. As for the change in color of the injected samples, it was observed that the increase in fiber generated a clear modification in the final shades of the pieces, reaching colors very similar to dark woods for percentages higher than 20% HF. Finally, the incorporation of an increasing percentage of fibers also increased water absorption due to its lignocellulosic nature in a linear way, which drastically improved the polarity of the composite


Author(s):  
Hang Nguyen Thi ◽  
Phuong Thao Le Thi ◽  
Huu Cuong Dang ◽  
Huyen Trang Luu Thi ◽  
Hong Hao Le Thi ◽  
...  

Vitamins are essential nutrients commonly found in food products in general and health supplements in particular. In order to accurately evaluate product quality, laboratories need to use reference material in analysis, proficiency assessment, method validation and ensure the validity of the results. The use of reference materials plays an important role in the quality control of test results and is a mandatory requirement for laboratories wishing to demonstrate appropriate competence as required by ISO/IEC 17025:2017. The need to provide reference materials for laboratories is huge. However, at present, there are very few domestic organizations that can produce reference materials, while the cost of buying reference materials from reputable firms in the world is expensive. In this study, we introduced the procedure and production reference materials for the analysis of B-group vitamins (B1, B2, B6). These reference materials were evaluated for homogeneity and stability in 322 days. The certified values are consistent with the concentrations of substances present in normal samples in practice. The measurement uncertainty ranges from 14.5 - 23.3 %. The reference materials can be used for internal quality control for domestic laboratories and is also a premise for further research on standard samples with different matrix and analytical criteria.


Author(s):  
L. K. Baybolova ◽  
A. K. Khaimuldinova ◽  
Zh. B. Asirzhanova

This article provides insights into qualification testing, interlaboratory comparative testing, and qualification testing programs in testing laboratories that analyze the safety of meat and meat products. Samples with codes OK-MB- 21 were used as a model for interlaboratory comparisons. The uniformity and stability of the CC code was assessed in accordance with GOST R 50779.60-2017 “Statistical methods. Application in proficiency testing through interlaboratory testing ”. Seven laboratories participated in the proficiency testing program. The test preparation procedure was described and the test results determined whether each sample tested was satisfactory or questionable. Participants with unsatisfactory results are encouraged to identify the causes of the alarms, take corrective actions and document them, and identify and eliminate the causes of the unsatisfactory results.


2021 ◽  
Author(s):  
Manikanta P ◽  
Hari Prasad B R ◽  
Sanjay B P ◽  
Sandeep S ◽  
Santhosh A S ◽  
...  

Abstract The work demonstrates the development of an electrochemical sensor for quantification of Chloramphenicol (CA) using pencil graphite electrode (PGE) modified with Gadolinium tungstate nano flakes and carbon nano fibers composite (PGE/GWNfs/CNFs). The composite was further characterized and confirmed by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), Transmission electron microscopy (TEM) analysis. The prepared GWNfs/CNFs nano composite was fabricated by drop casting method to get PGE/GWNfs/CNFs working electrode. The modified electrode is then analyzed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) methods for its electrochemical and electrocatalytic property. The electrochemical investigation of developed sensor shows enhanced activity towards electro-oxidation of CA. The DPV studies revealed high efficacy characteristics such as sensitivity in the range 0.03984 µA µM-1cm-2, selectivity, good linear range (5-50 μM), and low detection limit (0.4 μM). The study benchmarks the use of GWNfs/CNFs as an excellent transducer material in electrochemical sensing of CA in standard samples thus, it finds an efficient potential application in the analysis of CA in environment sample analysis.


2021 ◽  
Author(s):  
Sebastian Porebski ◽  
Tomasz Stokowy

Accurate identification of genetic variants to a large extent is based on type of experimental technology, quality of the material and coverage of obtained sequencing data. Our motivation was to create a tool that will evaluate genome coverage and accelerate the introduction of long-read sequencing to medical diagnostics and clinical practice. Here we present eXNVerify: a tool for inspection of clinical data in the context of pathogenic variants. The tool calculates Clinical Depth Coverage – a measure of coverage which we introduce to evaluate loci with pathogenic germline and somatic variants reported in ClinVar. The tool additionally provides visualization options for user-defined genes of interest. Finally, we present an examples of BRCA1, TP53, CFTR application and results of a test conducted in the Extensive Sequence Dataset of Gold-Standard Samples for Benchmarking and Development.


Pharmacia ◽  
2021 ◽  
Vol 68 (4) ◽  
pp. 933-939
Author(s):  
Oksana Strus ◽  
Mariana Fedorovska ◽  
Serhii Holota ◽  
Natalia Polovko

Methodological bases and uniform standardization criteria of humic compounds as substances for drug products have not been developed yet. This is due to the structural complexity of humic compounds, the variety of ways to extract them from natural objects, the impossibility of using many classical methods of analytical chemistry to identify and quantify humic substances (HS), the lack of standard samples. The identification of humic acids (HA) in the aqueous sapropel extract (ASE) is identified after extracting from ASE by alkaline hydrolysis by the quantification method. After further precipitation with a concentrated sulfuric acid solution characteristic dark brown color is appeared. It was carried out the HA extraction from the sample of ASE, the precipitation of HA, the oxidation of HA and Mohr’s salt titration in accordance with the methodology developed on the basis of SSTU 7083:2009. It was determined that the total mass fraction of HA in the ASE sample was 83.8 mg/g± 0.12%. The methods of identification and quantification of the total mass of HA in ASE have been developed and validated. The ASE has been standardized.


Metrologiya ◽  
2021 ◽  
pp. 40-52
Author(s):  
T. A. Kompan ◽  
V. I. Kulagin ◽  
V. V. Vlasova

The article describes a new method for enthalpy calibration of differential scanning calorimeters. The method allows you to remove the limitation on the temperature range in which this metrological procedure can be carried out. The proposed method does not require the use of standard samples of heats of fusion, therefore, it is not limited by the thermophysical properties of the certified substances. The developed method solves the problem of increasing the accuracy of measurements of specific enthalpy and heats of phase transitions of various substances for all types of differential scanning calorimeters. The effectiveness of the method in solving this problem is confirmed and illustrated by the authors by comparing the results of measuring the heats of fusion of a number of metals. The results obtained on differential scanning calorimeters calibrated by the new method and on the same instruments, but calibrated in accordance with the generally accepted standardized method of the International Union of Theoretical and Applied Chemistry, were compared. The authors experimentally revealed the advantages of the new method in terms of saving time and money required for calibration. The article will be of interest to those specialists who use differential scanning calorimeters in the development of new materials, control of technological processes, production, input and output control, as well as to those specialists who develop methods for research and measurement of various materials on differential scanning calorimeters.


2021 ◽  
pp. 231-240
Author(s):  
Ol'ga Valer'yevna Trineeva ◽  
Margarita Aleksandrovna Rudaya

An important role in the metabolism of ripening plant fruits is assigned to such a group of biologically active substances (BAS) as organic acids. This group of compounds accumulates in the fruits of plant objects in significant quantities, and the nature of the accumulation is in close relationship with metabolic processes, and is also determined by the influence of environmental factors, species and varietal characteristics of the plant. One of the promising plant sources of this group of BAS is the fruits of sea buckthorn (Hippophae rhamnoides L.). On the example of the fruits of ten different varieties of this plant, a comparative study of the profile of free organic acids was carried out using a complex of different methods of analysis (capillary electrophoresis (CE), thin layer chromatography (TLC), titrimetry). The cultivars with the maximum and minimum accumulation of BAS were identified. It was found that the composition of organic acids for the representatives of the variety samples is not the same, the maximum separation of chromatographic zones is observed in the variety «Ryabinovaya», the minimum - in the varieties «Stolichnaya», «Galerit», «Botanicheskaya», «Botanicheskaya amateur». The studied fruits were found to contain oxalic, malic, succinic and tartaric acids, identified using reliable standard samples. In the course of the research, specific marker zones were established, which can characterize the belonging of the fruits to a particular variety. The most informative is the method of СE, as it allows for one analytical procedure to carry out the qualitative and quantitative determination of free organic acids in acid and salt forms. However, complete information on the composition and quantitative content of acids can be obtained only by combining TLC and CE methods.


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