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A metrological technical specification for the purity assessment of organic pure substance certified reference materials (CRMs) in China was formulated based on the practical experience from CRM developers, comments from experts, the “IUPAC Organic Purity Technical Report—Methods for the SI Value Assignment of the Purity of Organic Compounds”, and other references. After review by the national metrological technical committee for reference material and other experts in China, the specification was issued as JJF 1855–2020 in 2020. The specification describes the principles, requirements and practical guidelines for the purity assessment of organic pure substance CRMs, such as mass balance, quantitative nuclear magnetic resonance, differential scanning calorimetry, coulometry, titrimetry and external standard calibration. It also describes the combination for results and uncertainties for different methods. In which, the classification of mass balance method into three types and the combination approach of value and uncertainty, especially suitable for the purity assessment are firstly introduced. The introduction of the consideration during formulation for each important section in the specification is inspirational and instructive to developers of organic pure substance CRMs around the world.

Certified reference materials are an essential tool for calibration of testing equipment, validation of analytical methods and ensuring quality of test results. Due to lack of national low temperature reference materials, Decahydronaphthalene reference material for flash point measurements according to ISO 13736has been developed by the National Metrology Institute of Egypt (NIS). This article describes production steps of the reference material. Certification of the material was carried out by interlaboratory comparisons, where between bottles homogeneity and stability studies were conducted in explosion protection department at PTB, Germany. The interlaboratory results were statistically analyzed, and robust mean was calculated as assigned value. The certified value and expanded measurement uncertainty (k = 2) was found 55.7 °C ± 1.2 °C, respectively.

Oxytocin (OXT) is an important peptide that is mainly used as a therapeutic drug to induce labor or strengthen uterine contractions, or to control bleeding after childbirth. OXT has also been reported as a biomarker linked to emotion, and as a potential biomarker for cancer diagnosis. The accurate purity characterization of OXT calibrators is critical for quality control of pharmaceuticals and the development of reference measurement systems for this analyte in laboratory medicine. OXT possesses the particular analytical measurement challenge of a disulfide bond. Accurate value assignment of the purity of oxytocin calibrators can be carried out by applying the mass balance approach or alternative approaches such as amino acid analysis, quantitative nuclear magnetic resonance spectrometry, and nitrogen determination. In order to avoid biases, all these approaches require a correction for structurally related peptide impurities. Structurally related peptide impurities present in a synthetic OXT material have been identified and quantified by a newly developed and in-house-validated liquid chromatography–high-resolution mass spectrometry (LC-hrMS) method. This method was adopted for the measurement of the study material used for an international comparison evaluating the competencies of laboratories to perform peptide characterization. Eighteen structurally related impurities were identified, confirmed, and accurately quantified in the OXT study material by using LC-hrMS. The study material contained a total mass fraction of 31.1 mg/g structurally related OXT impurities with an associated expanded uncertainty of 1.7 mg/g.

Certified reference materials (CRM) are essential tools for calibration of measuring instruments, validation of analytical methods and assuring quality of measurement results. However, in the case of the mass fractions protein and moisture in wheat flour, which is used to determine the quality and the market ability of flour, there is a lack of matrix reference materials. CRM for protein and moisture in wheat flour has been measured by the National Institute of Standards, Egypt. This article describes the value assignment of the mass fractions nitrogen and moisture in wheat flour by using Kjeldahl and dry oven; then, measuring the samples by inframatic analyzer system, the results were statistically analyzed and weighted mean; the results were found to be 10.33 % ± 0.36 % (k = 2) for protein and 16.98 % ± 0.30 % (k = 2) for moisture (as mass fractions). Finally, with performance test program for the samples used from wheat flour our lab reported satisfactory results.

Since 1 January 2019 a maximum content of 0.6 mg kg−1 cadmium (Cd) in cocoa powder sold to the final consumer or as an ingredient in sweetened cocoa powder sold to the final consumer (drinking chocolate) is set by the Commission Regulation (EU) No. 488/2014. Monitoring compliance with the specified limit value requires analytical measuring methods and reference materials for quality control. However, suitable certified reference materials intended for quality assurance and quality control purposes are still lacking. Therefore, three cocoa reference materials (ERM®-BD513, ERM®-514 and ERM®-515) were developed according to the requirements of ISO 17034 and the recommendations of ISO Guide 35. The whole process of reference material development, including material preparation, assessment of homogeneity and stability, characterisation and value assignment is presented. The assignment of the certified mass fractions was based upon an interlaboratory comparison study involving 19 expert laboratories for Cd and 12 laboratories for acrylamide. The certified mass fractions and expanded uncertainties (k = 2) of the reference materials were (0.181 ± 0.009) mg kg−1 Cd (ERM®-BD513), (0.541 ± 0.024) mg kg−1 Cd (ERM®-BD514) and (0.690 ± 0.029) mg kg−1 Cd (ERM®-BD515). Acrylamide contents are given for information.

VITA-1 and VITB-1 are low- and elevated level CRMs, respectively, which were certified for minerals and vitamin contents by National Research Council Canada. The proportions of key ingredients are the same in each formula, and they were prepared in such a way that VITB-1 has twice the amount of minerals and vitamins as VITA-1. The availability of these two matrix-matched CRMs, with different concentrations for all analytes, will not only assist in the validation of procedures and the development of methods for the determination of respective analytes in multivitamins or samples of a similar matrices, but also will be useful for calibration purposes (for the values that are certified). Tablets were individually packaged in trilaminate foil pouches and values presented in the certificate of analysis are expressed on a “as is” basis, with no need for the determination of moisture content on a separate test portion. In addition, certified/reference values are provided per single tablet (mass fraction expressed as both mg/kg and µg/tablet), eliminating the need of a homogenization step prior to analysis. Homogeneity and stability were assessed and included in the final expanded uncertainties of the certified values. Quantity value assignment for both VITA-1 and VITB-1 was based on the use of at least two independent methods, using data generated at NRC and data from external collaborators for confirmation purposes. As a result of this campaign, value assignment was possible for a total of 39 analytes: 24 trace elements and 15 vitamins.

In this study, the proposed Optimum Gamma Value Assignment (OGVA) method is intended to dynamically optimize the image intensity level in non-desired images due to undesired light levels. For this purpose, it is aimed to make the dark images which cannot be seen due to lack of light, while bright images are dynamically dimmed by using the optimum gamma correction value applied on the image momentarily. It has been shown that this novel method, which will only be implemented as software, without requiring any additional hardware, yields satisfying results even at different light levels.

Matrix certified reference materials (CRMs) are an indispensable part of method validation and have played an important role in ensuring reliable analytical results. To retain similarity to real samples, a new matrix CRM for the mass fraction of ciprofloxacin in whole liquid egg was developed by use of incurred materials with a target value corresponding to residue levels in real sample. The source materials were collected from laying hens following oral administration of ciprofloxacin. An optimized homogenization method and a strict bottling process were applied to bulk whole egg materials to prepare the CRM candidate. The mass fraction of ciprofloxacin in whole liquid egg was certified by a collaborative characterization program with eight accredited participating laboratories. Liquid chromatography coupled with isotope dilution mass spectrometry was studied as a reliable reference method for value assignment and was used by all participating laboratories. The certified value and expanded uncertainty (k = 2, at a confidence level of 95%) was 39.7 ± 5.2 μg/kg for ciprofloxacin in whole liquid egg. Homogeneity, long-term stability at -70 °C for 12 months, and short-term stability at -18 °C, 4 °C, and room temperature were assessed for 9 days. Additionally, uncertainties arising from inhomogeneity, instability, and characterization were analyzed in detail and fully estimated. This CRM would be a useful tool for validation of analytical methods and proficiency testing in ciprofloxacin residue analysis of egg. Graphical Abstract.

Highlights • LC-MS/MS-based candidate reference method for the quantification of androstenedione. • Certified reference material from NMIA with additional qNMR characterization. • Uncertainty evaluation according to the GUM 1995. • Inter laboratory comparison study and comparison to a routine LC-MS/MS assay., The accurate measurement of androstenedione in human serum and plasma is required for steroid profiling to assure the appropriate diagnosis and differential diagnosis of hyperandrogenism. In this work, we introduce an isotope dilution liquid chromatography–tandem mass spectrometry (LC–MS/MS) candidate reference measurement procedure for the quantification of androstenedione in human serum and plasma. The performance of the procedure enables its use in the evaluation and standardization of routine assays and for the evaluation of patient samples to ensure the traceability of individual patient results. As the primary standard, a certified reference material from NMIA (National Measurement Institute, Australia) was used. Additionally, a quantitative nuclear magnetic resonance (qNMR) method was developed for the value assignment of the primary reference material, which ensures the direct traceability to SI units, as well as the independence from the availability of reference materials. 13C3-labeled androstenedione was used as the internal standard. The introduced method allows the measurement of androstenedione in the range of 0.05–12 ng/mL, and the assay imprecision was found to be

A candidate digital PCR (dPCR)-based reference measurement procedure for quantification of human cytomegalovirus (hCMV) was evaluated in 10 viral load comparison schemes (seven external quality assessment (EQA) and three additional training schemes) organized by INSTAND e.V. over four years (between September 2014 and March 2018). Four metrology institutes participated in these schemes using the same extraction method and dPCR measurement procedure for the hCMV specific target sequence of UL54 gene. The calibration independent reference measurement procedure results from the metrology institutes were compared to the results of the clinical diagnostic laboratories applying hCMV qPCR measurement procedures calibrated to reference materials. While the criteria for the acceptable deviation from the target value interval for INSTAND's EQA schemes is from-0.8 log10 to +0.8 log(10), the majority of dPCR results were between-0.2 log10 to +0.2 log(10). Only 4 out of 45 results exceeded this interval with the maximum deviation of-0.542 log(10). In the training schemes containing samples with lower hCMV concentrations, more than half of the results deviated less than +/- 0.2 log(10) from the target value, while more than 95% deviated less than +/- 0.4 log(10) from the target value. Evaluation of intra-and inter-laboratory variation of dPCR results confirmed high reproducibility and trueness of the method. This work demonstrates that dPCR has the potential to act as a calibration independent reference measurement procedure for the value assignment of hCMV calibration and reference materials to support qPCR calibration as well as ultimately for routine hCMV load testing. This study was financially supported by the INFECTMET project (the EMRP project; jointly funded by the EMRP participating countries within EURAMET and the European Union, project no. HLT08); AntiMicroResist project (which has received funding from the EMPIR program co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation program, project no. 15HLT07); the Slovenian Research Agency (contract no. P4-0165 and 1000-13-0105); Ministry of Education, Science and Sport of republic of Slovenia (contract no. 3330-14-500133) and supported by the UK National Measurement System. The dPCR equipment used at NIB in this study was financed by the Metrology Institute of the Republic of Slovenia (MIRS), with financial support from the European Regional Development Fund. The funding source(s) had no involvement in study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the article for publication. This publication reflects only the authors’ s views and EURAMET is not responsible for any use that may be made of the information it contains.

Background: Matrix-matched reference materials (RMs) are critical for adequate quality assurance of extraction, digestion, separation, and/or detection processes for analytes of interest in foods and dietary supplements. The accurate determination of mycotoxins in foods is an international concern. While RMs for mycotoxins are available from a variety of RM producers, these mainly address a single mycotoxin or group of mycotoxins and therefore require the use of multiple RMs for multitarget methods. Objective: To address the increasing needs of laboratories moving toward LC-MS-based multimycotoxin analysis, the U.S. National Institute of Standards and Technology (NIST) collaborated with the U.S. Food and Drug Administration (FDA) to produce a naturally incurred RM for multiple mycotoxins in corn. Methods: Homogeneity of the RM has been assessed using a stratified random sampling of the final product based on mycotoxin mass fractions measured by the FDA and NIST. Multiple sample sizes were evaluated to maximize homogeneity in the obtained results. The mycotoxin levels in the final materials have been evaluated via interlaboratory comparison and isotope dilution LC–tandem MS measurements made at the FDA and NIST. The final value assignment combined results from these data sets. Conclusions: The study successfully developed a certified RM, SRM 1565 Mycotoxins in Corn, and a workflow for the future development of multimycotoxin RMs in different matrices.

Polycyclic aromatic hydrocarbons (PAHs) are a large group of priority organic pollutants, which contaminate environmental compartments, food, and consumer products as well. Due to their frequent occurrence associated with elevated levels of PAHs, plastic and rubber parts of consumer products and toys are particular sources of exposure. Although European maximum levels exist for eight carcinogenic PAHs in consumer products and toys according to REACH Regulation (EC) No. 1907/2006, certified reference materials (CRM) are still not available. To overcome this lack, the first CRM for the determination of PAHs in rubber toys (BAM-B001) was developed according to the requirements of ISO Guide 35. The whole process of CRM development including preparation, homogeneity and stability studies, and value assignment is presented. The assignment of the certified mass fractions was based upon in-house study at BAM using stable isotope dilution analysis (SIDA) gas chromatography mass spectrometry (GC–MS). The obtained values were confirmed by the results of two interlaboratory comparison (ILC) studies with more than 50 expert laboratories from Germany and China. The mass fractions of 14 PAHs including all REACH and GS mark regulated compounds were certified ranging between 0.2 and 15.4 mg/kg accompanied by expanded uncertainties (coverage factor k = 2). In addition, informative values were determined for 4 PAHs, mainly due to higher uncertainties and/or lack of ILC data for confirmation. BAM-B001 is intended for analytical quality control particularly based on the AfPS GS 2019:01 PAK method and contributes to improve the chemical safety of consumer products including toys. Graphical abstract

2019 the outbreak of New Coronavirus pneumonia COVID-19 in Wuhan is characterized by high infectivity, long incubation period and high mortality rate. It seriously interferes with the normal production activities during the outbreak. Therefore, it is of great significance to study its transmission mechanism and the future development trend. In this paper, the SEIR model of new coronavirus was established, and the value assignment method and least square method were used to solve the model. The fitting results and the real value had a good match, indicating that the model was more reasonable. The epidemic data of Wuhan, Guangdong and Brazil were analyzed and predicted respectively. The analysis found that the epidemic situation in Wuhan was basically stable; the epidemic situation in Guangdong was relatively late, and the control was relatively timely. The epidemic situation in Brazil started in the middle of March, so the mortality rate continued to rise from March to April, but the cure rate remained low. The epidemic prevention and control suggestions were put forward to Wuhan, Guangdong and Brazil respectively. The theoretical analysis of the model shows that prevention and control isolation and medical tracking isolation play an important role in inhibiting the large-scale spread of the epidemic. In addition, individuals improve their awareness of prevention and take strict self-protection measures to curb the increase in the number of infected people. The SEIR epidemic model of the new coronavirus established in this paper can be used for covid-19 The purpose of this study is to provide theoretical support for making future intervention decisions

Microgrids interfaced with distributed generators facilitate decentralization of electric power. Bi-directional power flow due to multiple sources and dynamic behaviour of microgrids possess challenges to protection engineers. In this paper, an adaptive protection scheme for a central protection centre (CPC) in a microgrid is proposed. The key functions of the CPC are monitoring the microgrid, identification of fault if any, shortest path identification from a fault to the nearest operating source using Boruvka–Dijkstra graph theory algorithm. It also assigns adaptively the optimized values of time multiplier setting of relays in that path using genetic algorithm, which in turn aids in quick fault clearance. A hardware prototype is developed, tested and validated for a 7-bus microgrid network using Arduino ATmega 1280 for shortest path identification and optimized TMS value assignment for relays in that path using Raspberry Pi Model B+.

The production of reference materials (RMs) is a key activity for the improvement and maintenance of a worldwide coherent measurement system. General requirements for the production of all types of RMs are set out in ISO 17034:2016. These general requirements include a characterisation strategy with a note that references the list of approaches that are discussed in more detail in the new ISO Guide 35:2017. This paper provides an overview of the characterisation approaches explained in technical detail in the new ISO Guide 35:2017, with particular attention being paid to changes from the 2006 edition. Important changes include a clear distinction between the use of a single method in a single-laboratory approach when the method can be validated with a certified reference material (CRM) of the same kind as the candidate reference material compared to when a similar CRM is not available. For the approach where more than one method is used in one or more laboratories, the concept of the importance of the number of independent data sets is explained in more detail. A lot more technical detail is also provided for the use of an interlaboratory comparison for the certification study.

Background Poor comparability between laboratories is often observed in the measurement of HbA2. A measurement procedure of higher metrological order is needed for value assignment to a reference material that shall be used as primary calibrator. Method A reference measurement procedure has been developed based on isotope dilution mass spectrometry (IDMS). The α- and δ- subunits are quantified by signature peptides released by tryptic digestion of a 25 μL-blood sample. Full length U-15N-labeled HbA0 and HbA2 are used as internal standards and added to the sample at concentrations closely matching the levels of the natural forms in blood. By this, an improvement in precision could be achieved with respect to previous mass-spectrometry based methods. Results Recovery of HbA2 added to a blood sample was within 102.6–105.2%. Repeatability and within-laboratory imprecision was Conclusion IDMS holds a promise to be suitable as a reference measurement procedure for standardization of HbA2-measurements in laboratory medicine.

Purpose To investigate the potential of an atlas‐based approach in generation of synthetic CT for pelvis anatomy. Methods Twenty‐three matched pairs of computed tomography (CT) and magnetic resonance imaging (MRI) scans were selected from a pool of prostate cancer patients. All MR scans were preprocessed to reduce scanner‐ and patient‐induced intensity inhomogeneities and to standardize their intensity histograms. Ten (training dataset) of 23 pairs were then utilized to construct the coregistered CT‐MR atlas. The synthetic CT for a new patient is generated by appropriately weighting the deformed atlas of CT‐MR onto the new patient MRI. The training dataset was used as an atlas to generate the synthetic CT for the rest of the patients (test dataset). The mean absolute error (MAE) between the deformed planning CT and synthetic CT was computed over the entire CT image, bone, fat, and muscle tissues. The original treatment plans were also recomputed on the new synthetic CTs and dose–volume histogram metrics were compared. The results were compared with a commercially available synthetic CT Software (MRCAT) that is routinely used in our clinic. Results MAE errors (±SD) between the deformed planning CT and our proposed synthetic CTs in the test dataset were 47 ± 5, 116 ± 12, 36 ± 6, and 47 ± 5 HU for the entire image, bone, fat, and muscle tissues respectively. The MAEs were 65 ± 5, 172 ± 9, 43 ± 7, and 42 ± 4 HU for the corresponding tissues in MRCAT CT. The dosimetric comparison showed consistent results for all plans using our synthetic CT, deformed planning CT and MRCAT CT. Conclusion We investigated the potential of a multiatlas approach to generate synthetic CT images for the pelvis. Our results demonstrate excellent results in terms of HU value assignment compared to the original CT and dosimetric consistency.

RATIONALE LSVEC, the second anchor Reference Material (RM) for the VPDB δ13 C scale realisation, was introduced in 2006. In 2015, its δ13 C value was found to be drifting and, in 2017, its use as an RM for δ13 C was officially discontinued by IUPAC. New RMs of low uncertainty are needed. This paper describes the preparation and characterisation of IAEA-610, IAEA-611 and IAEA-612 (calcium carbonate, of chemical origin) which shall serve as a set of RMs aimed at anchoring the VPDB scale at negative δ13 C values. METHODS The preparation and characterisation of IAEA-610, IAEA-611 and IAEA-612 were performed by addressing the contemporary technical requirements for RM production and characterisation (ISO Guide 35:2017). The three RMs were produced in large quantities, and the first batch was sealed into ampoules (0.5 g) to ensure the integrity of the RM during storage; additional batches were sealed for long-term storage. The most accurate method of CO2 preparation and stable isotope measurements was used, namely carbonate-H3 PO4 reaction under well-controlled conditions combined with well-tested stable isotope ratio mass spectrometry. RESULTS The assigned values of δ13 C and associated uncertainties are based on a large number of analyses (~10 mg aliquots) performed at IAEA and address all the known uncertainty components. For aliquots down to ~100 μg, the δ13 C uncertainty is increased. The uncertainty components considered are as follows: (i) material homogeneity, (ii) value assignment against IAEA-603, (iii) potential storage effects, (iv) effect of the 17 O correction, and (v) mass spectrometer linearity and cross-contamination memory in the ion source. CONCLUSIONS The new RMs IAEA-610, IAEA-611 and IAEA-612 have been characterised on the VPDB δ13 C scale in a mutually consistent way. The use of three RMs will allow a consistent realisation of the VPDB δ13 C scale with small uncertainty to be established, and to reach metrological compatibility of measurement results over several decades.

This study aims to propose the concept of intuitionistic fuzzy parameterized intuitionistic fuzzy soft matrices (ifpifs-matrices) and to present several of its basic properties. Therefore, it would be possible to improve the problem-modelling capabilities of the available intuitionistic fuzzy parameterized intuitionistic fuzzy soft sets in the occurrence of a large number of data. Moreover, by using ifpifs-matrices, we suggest a new soft decision-making method, denoted by EA20, and apply it to a multi-criteria group decision-making (MCGDM) problem. We then compare the ranking performance of EA20 for five noise-removal filters with those of ten state-of-the-art soft decision-making methods. The results show that EA20 successfully models performance-based value assignment problems. Finally, we discuss ifpifs-matrices and EA20 for further research.

Measurement of Thrombin-activatable fibrinolysis inhibitor (TAFI) in human plasma is dependent on reproducible assays. To date, standards for measuring TAFI are frequently calibrated relative to pooled normal human plasma and arbitrarily assigned a potency of 100% TAFI, despite variation in TAFI concentrations between plasma pools. Alternatively, TAFI calibrators can be assigned a value in SI units but the approach used for value assignment is not consistent and furthermore, if purified TAFI is used to determine TAFI concentration in plasma, may be adversely affected by matrix effects. A TAFI plasma standard in mass units with traceability to the SI unit of mass is desirable. We report here the establishment of a quantitative mass spectrometry method for TAFI in plasma. Traceability is obtained by reference to calibrators that consist of blank plasma spiked with a defined amount of purified TAFI, value assigned by amino acid analysis. The calibrators are run alongside the samples, using the same preparation steps and conditions; an acetonitrile assisted tryptic digestion and multi-dimensional liquid chromatography (LC) separation followed by SRM-MS analysis. We measured the TAFI quantitatively in human plasma with reproducibility, reliability and precision, and demonstrated the applicability of this approach for value assigning a common reference standard.

Rationale NBS19 carbonate, a primary reference material (RM) for the Vienna Pee Dee Belemnite (VPDB) scale realisation introduced in 1987, was exhausted in 2009, and no primary RM was available for several years. This study describes the preparation and characterisation of a new RM, IAEA-603 (Ca-carbonate, calcite of marble origin), which shall serve as a new primary RM (replacement for NBS19) or primary calibrator aimed at the highest realisation of the VPDB scale for δ13 C and δ18 O values, including the VPDB-CO2 δ18 O scale. Methods IAEA-603 preparation and characterisation (value transfer) against NBS19 were performed by addressing the major modern technical requirements for the production and characterisation of RMs (ISO Guide 35). IAEA-603 was produced in a large quantity, and the first batch was sealed into ampoules (0.5 g) to ensure RM integrity during storage; four other batches were sealed for long-term storage. The most accurate method of CO2 preparation for isotope mass spectrometry was used, namely carbonate-H3 PO4 reaction under controlled conditions. Results The assigned values of δ13 C = +2.460 ± 0.010‰ and δ18 O = -2.370 ± 0.040‰ (k = 1) are based on a large number of analyses (~10 mg aliquots) performed at IAEA and address all the known uncertainty components. For aliquots down to 120 μg, the δ18 O uncertainty remains unchanged but shall be doubled for δ13 C. The uncertainty components considered are as follows: (a) material homogeneity (within and between the 5200 ampoules produced), (b) value assignment against NBS19, (c) storage effects and (d) effect of the 17 O correction. Conclusions The new primary RM IAEA-603 replaces NBS19 in its use as the highest calibrator for the VPDB δ13 C and δ18 O scale, including the VPDB-CO2 δ18 O scale. The use of IAEA-603 will allow laboratories worldwide to establish consistent realisation of the scales for δ13 C and δ18 O values and metrological comparability of measurement results for decades. The VPDB scale definition based on NBS19 stays valid.

Hydrogen permeation techniques have been widely utilized to extract hydrogen effective diffusivity, as well as hydrogen trapping site characteristics in steels. Several methods have been proposed to examine reversible and irreversible trapping site characteristics. However, the inappropriate utilization of these simplified models, as well as incorrect value assignment to the key parameters, can result in several orders of magnitude difference in hydrogen trapping site density. Therefore, in order to evaluate these models and verify their application prerequisites, a serial of hydrogen permeation tests were numerically simulated and examined, separately considering reversible and irreversible hydrogen trapping sites. In the meantime, suggestions were given to conduct hydrogen permeation test more effectively, and evaluate hydrogen trapping site characteristics more precisely.

In this paper, we develop, implement, test, and analyze a novel technique that allows to improve the security and safety of intersections crossing by the group of autonomous vehicles. The proposed approach is based on augmenting the trust and reputation models with data quality evaluation and using it for initial trust value assignment. This technique allows increasing accuracy and recall rates in detecting agents that might supply incorrect data and facilitating their removal from the agent group consideration. To evaluate the proposed method, we performed the simulation study of the autonomous vehicle traffic control through an intersection. The conducted experiments showed that the employment of data quality metrics improves detecting autonomous vehicles and other agents that might transmit incorrect data.

Introduction:. Comprehensive mRNA sequencing is a powerful tool for conducting unbiased, quantitative differential gene expression analysis. However, the reliability of these data is contingent on the extraction of high-quality RNA from samples. Preserving RNA integrity during extraction can be problematic, especially in tissues such as skin with dense, connective matrices and elevated ribonuclease expression. This is a major barrier to understanding the influences of altered gene expression in many preclinical pain models and clinical pain disorders where skin is the site of tissue injury. Objective:. This study developed and evaluated extraction protocols for skin and other tissues to maximize recovery of high-integrity RNA needed for quantitative mRNA sequencing. Methods:. Rodent and human tissue samples underwent one of the several different protocols that combined either RNA-stabilizing solution or snap-freezing with bead milling or cryosectioning. Indices of RNA integrity and purity were assessed for all samples. Results:. Extraction of high-integrity RNA is highly dependent on the methods used. Bead-milling skin collected in RNA-stabilizing solution resulted in extensive RNA degradation. Snap-freezing in liquid nitrogen was required for skin and highly preferable for other tissues. Skin also required cryosectioning to achieve effective penetration of RNA-stabilizing solution to preserve RNA integrity, whereas bead milling could be used instead with other tissues. Each method was reproducible across multiple experimenters. Electrophoretic anomalies that skewed RNA integrity value assignment required manual correction and often resulted in score reduction. Conclusion:. To achieve the potential of quantitative differential gene expression analysis requires verification of tissue-dependent extraction methods that yield high-integrity RNA.

Interactions between road users, motor vehicles, and environment affect to driver’s travel behavior; however, frailer of proper interaction may lead to ever-increasing road crashes, injuries and fatalities. The current study has generated the green driver concept to evaluate the incorporation of green driver to negative outcomes reduction of road transportation. The study aimed to identify the green driver’s behaviors affecting safe traveling by engaging two research phases. Phase one was to identify the safe driving behaviors using Systematic literature review and Content Analysis methods. Phase one identified twenty-four (24) sub-factors under reckless driving behaviors cluster, and nineteen (19) sub-factors under safe driving practice cluster. Second phase was to establish the actual weight value of the sub-factors using Grounded Group Decision Making (GGDM) and Value Assignment (VA) methods, in order to determine the value impact of each sub-factor to green driving. Phase two resulted that sub-factors Exceeding speed limits (DB f2.2.) and Driver’s cognitive and motor skills (SD f1.2.2.) have received highest actual values, 0.64 and 0.49, respectively; ranked as the High contributor grade. Contrary, the sub-factors Age cognitive decline (DB f1.2.) and Competitive attitude (DB f1.2.), and Avoid gear snatching (SD f1.1.4.) have the lowest actual values; and ranked in low-contribution grade. The rest of the sub-factors have ranked in medium-contribution grade. The research also found out drivers’ personalities (included, physical and psychological characteristics) remains unaccountable and non-measureable yet in driver travel behavior assessment models. The study outputs would be used in development of Green Driver Index Assessment Model.

In the paper, a value assignment for projection operators relating to a quantum system is equated with assignment of truth-values to the propositions associated with these operators. In consequence, the Kochen-Specker theorem (its localized variant, to be exact) can be treated as the statement that a logic of those projection operators does not obey the principle of bivalence. This implies that such a logic has a gappy (partial) semantics or many-valued semantics., This is a pre-print of an article published in Quantum Studies: Mathematics and Foundations. The final authenticated version is available online at: https://doi.org/10.1007/s40509-018-0173-y, Quantum Stud.: Math. Found. (2018)

A Bayesian statistical procedure is proposed for value assignment and uncertainty evaluation for the mass fraction of the elemental analytes in single-element solutions distributed as NIST standard ...

Accurate diagnosis, monitoring and treatment are cornerstones of a healthcare system and require reliable measurements. The traceability of measurement results to stated references, and the development of Reference Measurement Systems (RMS), provide mechanisms to achieve the required consistency of results. The primary standards within such an RMS are of pure substance certified reference materials. Developments in modern measurement and mass spectrometric techniques have opened up the possibility to characterize and quantify more complex large molecules such as peptides, enabling RMS to be developed for these analytes. The prohormone angiotensin I is a hypertension biomarker and was selected as a model peptide. The full mass balance approach, the peptide impurity corrected amino acid analysis, elemental analysis and quantitative nuclear magnetic resonance approaches have been investigated and optimized to compare the performance of these different methodologies for the purity mass fraction value assignment of an ANG I calibrator material.

A novel type of reference material has been prepared and characterized for smoke density chamber calibration in the flame condition by Fire Protection Laboratory, National Institute of Standards, Egypt. The new reference material was fabricated by mixing modified magnesium hydroxide nanoparticles (MH-NP-OP) with acrylonitrile–butadiene–styrene copolymer (ABS). The reference material was certified for the physical properties of maximum specific optical density (Dm) and corrected maximum specific optical density (Dm·corr) using the analysis of two different competent laboratories. Preparation, characterization, homogeneity testing and certified value assignment for the developed reference material have been studied. It was clearly demonstrated that the smoke measurement of the two laboratories are harmonic which is an obvious prerequisite for the confidence assessment of the reference material. A metrological approach was followed to detect the statistical biases between different laboratories data to achieve an appropriate accuracy in smoke measurements. The obtained measurement results were statistically analyzed and the certified values of Dm and Dm·corr for reference material were estimated as 510.35 and 472.95, respectively as well as their expanded relative uncertainties at confidence level 95% were recorded 2.78 and 2.7%, respectively. The developed reference material are expected to be used to assist in validating smoke measurements of different materials to realize their fire hazard when be used in building.

The NISTmAb Reference Material (RM) 8671 is intended to be an industry standard monoclonal antibody for pre-competitive harmonization of best practices and designing next generation characterization technologies for identity, quality, and stability testing. It must therefore embody the quality and characteristics of a typical biopharmaceutical product and be available long-term in a stable format with consistent product quality attributes. A stratified sampling and analysis plan using a series of qualified analytical and biophysical methods is described that assures RM 8671 meets these criteria. Results for the first three lots of RM 8671 highlight the consistency of material attributes with respect to size, charge, and identity. RM 8671 was verified to be homogeneous both within and between vialing lots, demonstrating the robustness of the lifecycle management plan. It was analyzed in concert with the in-house primary sample 8670 (PS 8670) to provide a historical link to this seminal material. RM 8671 was verified to be fit for its intended purpose as a technology innovation tool, external system suitability control, and cross-industry harmonization platform. Graphical abstractThe NISTmAb Reference Material (RM) 8671 is intended to be an industry standard monoclonal antibody for pre-competitive harmonization of best practices and designing next generation characterization technologies for identity, quality, and stability testing. Electronic supplementary material The online version of this article (10.1007/s00216-017-0800-1) contains supplementary material, which is available to authorized users.

A new matrix certified reference material (CRM) of florfenicol in prawn meat powder [GBW(E)100638] was developed for validation of analytical method and assurance of measurement quality in the routine monitoring of prawn food safety. The incurred prawn materials were freeze-dried, ground, sieved, homogenized, bottled and gamma-irradiated to prepare the CRM candidates. For characterization of the CRM, isotope dilution coupled with liquid chromatography tandem mass spectrometry as a reliable and accurate method was studied and employed by all participants in co-laboratory value assignment program. The certified value with expanded uncertainty (k = 2, at a confidence of 95%) was 11.8 μg/kg ± 1.9 μg/kg for florfenicol in prawn meat powder. Homogeneity, long-term stability of fifteen months at −20℃ for storage, and short-term stability of nine days at 4℃, 20℃ and 40℃ for transportation and use were examined. In addition, uncertainties originating from characterization, inhomogeneity and instability were assessed.

espanolEn la actualidad, ha tomado fuerza e incrementado su importancia, el valor del capital intelectual en las empresas; se reconoce que debe formar parte de los estados financieros, ya que la riqueza es generada por personas asi como el negocio mismo. Se presenta el problema de como asignarle un valor, por lo que los estudios e investigadores de negocios se han dado a la tarea de buscar indicadores que muestren como las personas y las propias organizaciones generan valor creando una serie de modelos que son utilizados por diversas empresas sobre todo aquellas que son competitivas y que van a la vanguardia en el mundo de los negocios. Se presentan de manera breve algunos modelos que a traves del tiempo se han ido disenando, tratando de sustentar la asignacion de valor, coincidiendo algunos de ellos en los varios criterios que manifiestan que agregan valor a las empresas. Se analiza la normatividad contable vigente, en relacion a los activos intangibles y su tratamiento en cuanto a su valuacion y reflejo en la informacion financiera. El problema es como asignarle valor al capital intelectual de manera sustentada y razonable con el objetivo que desde el punto de vista contable se tangible y se puede reflejar en la informacion financiera. El trabajo es una revision analitica de la bibliografia existente llegando a la conclusion de que existen diversos criterios que ayudan a asignarle valor a traves de algunas manifestaciones y conceptos que estan presentes en los individuos y en las organizaciones pero de manera subjetiva. EnglishCurrently, it has gained strength and increased its importance, currently, the value of intellectual Business, has gained; it is recognized that it must be part of the financial statements, since wealth is generated by people as well as the business itself. The problem of how to assign a value to it, is presented, so studies and business researchers have been given to the task of looking for indicators that show how people and the organizations themselves generate value by creating a series of models that are used by diverse companies especially those that are competitive and that are at the forefront in the world of business. Some models are presented in a brief way Through time they have been designing, trying to sustain the value assignment, some of them coinciding of them in the various criteria that state that They add value to companies. The current accounting regulations are analyzed, in relation to intangible assets and their treatment in regarding its valuation and reflection in the financial information The problem is how to assign value to intellectual capital in a sustained and reasonable way with the goal that from the accounting point of view is tangible and can be reflected in the financial information The work is an analytical review of the existing bibliography reaching the conclusion that There are several criteria that help to assign value to you through some manifestations and concepts that are present in individuals and in organizations but in a subjective way.