LEICA DMC III CALIBRATION AND GEOMETRIC SENSOR ACCURACY

Quality Assurance and Quality Control (QA/QC) is a critical component of all pXRF geochemistry processes. A properly constructed pXRF QA/QC programme identifies possible instrumental errors and provides a means of securing fit for purpose data from the pXRF programme. pXRF QA/QC programmes involve daily contamination, precision, and accuracy checks to ensure the generation of fit for purpose data. In the exploration field or mine-site, pXRF is capable of producing extremely valuable data that is fit for purpose if calibrated properly. However, it should not be used as a replacement for acquiring data from an accredited laboratory using established analytical techniques that produce high quality data. Contamination is the checking of the cleanliness of the analyser window or the presence of dust in the measuring environment. At Polymetals, using Olympus Vanta C-Series pXRF analyser with silver anode, contamination is assessed by measuring an instrumental blank (SiO2), to identify any foreign matter on the analyser window. Assuming that the window film is new, and the fused silica disc is dust free, only Si should be detected. If any other significant element is detected, the film is replaced, and the test is re-run. Accuracy is a measure of how close the measured value is to the true value and is assessed by measuring the abundance of selected elements contained within a Certified Reference Material (CRM) or the NIST check standard sample supplied with the pXRF analyser. Elements of interest must report within ±20% of the standard value. Precision is a measure of how close repeat measurements are to one another and is assessed by taking multiple readings on a particular sample to determine the stability of the analyser. The Relative Standard Deviation (RSD) of the replicate measurements is then calculated. The RSD values should be less than 20% for most analytes, except chromium, for which the value should be less than 30%. Once contamination, accuracy and precision are within accepted limits, the batch/daily measurements are considered to have passed the QA/QC protocol. The data is thus fit for purpose and transferred to the data file. Any batch/daily measurement reported to have failed due to instrumental errors is re-analysed. QA/QC protocols should be applied to each project. The QQ/QC protocols instituted after the pXRF samples meeting the quality sample conditions thus pulverised dry samples in pXRF sample cup covered with thin pXRF films, are used to generate fit for purpose data from soils samples at Mansala which is used to generate pathfinder element(s) to delineate anomalous pathfinder trends for further exploration works.

Developing a quality assurance and quality control (QA/QC) plan is an important element of any surveillance logging program. A QA/QC plan is used to document how quality assurance (QA) and quality control (QC) activities will be implemented during a program, project, or task1. A QA/QC Plan for a surveillance logging program can provide adequate and accurate information in assessing the level of pipe defects reported from casing inspection logs and can be used to record possible trends regarding the individual casing inspection tools. It may also analyze data to characterize errors in measuring tubular thickness as well as monitor tool accuracy and data interpretation.

Wastewater surveillance for pathogens using reverse transcription-polymerase chain reaction (RT-PCR) is an effective and resource-efficient tool for gathering community-level public health information, including the incidence of coronavirus disease-19 (COVID-19). Surveillance of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) in wastewater can potentially provide an early warning signal of COVID-19 infections in a community. The capacity of the world's environmental microbiology and virology laboratories for SARS-CoV-2 RNA characterization in wastewater is increasing rapidly. However, there are no standardized protocols or harmonized quality assurance and quality control (QA/QC) procedures for SARS-CoV-2 wastewater surveillance. This paper is a technical review of factors that can cause false-positive and false-negative errors in the surveillance of SARS-CoV-2 RNA in wastewater, culminating in recommended strategies that can be implemented to identify and mitigate some of these errors. Recommendations include stringent QA/QC measures, representative sampling approaches, effective virus concentration and efficient RNA extraction, PCR inhibition assessment, inclusion of sample processing controls, and considerations for RT-PCR assay selection and data interpretation. Clear data interpretation guidelines (e.g., determination of positive and negative samples) are critical, particularly when the incidence of SARS-CoV-2 in wastewater is low. Corrective and confirmatory actions must be in place for inconclusive results or results diverging from current trends (e.g., initial onset or reemergence of COVID-19 in a community). It is also prudent to perform interlaboratory comparisons to ensure results' reliability and interpretability for prospective and retrospective analyses. The strategies that are recommended in this review aim to improve SARS-CoV-2 characterization and detection for wastewater surveillance applications. A silver lining of the COVID-19 pandemic is that the efficacy of wastewater surveillance continues to be demonstrated during this global crisis. In the future, wastewater should also play an important role in the surveillance of a range of other communicable diseases.

Quality laboratory services are a requisite to guide rational case management of malaria. Using a pre-tested, standardized assessment tool, we assessed laboratory diagnostic capacity in 69 primary, secondary and tertiary health facilities as well as specialized laboratories in five administrative zones in Oromia Regional State, Ethiopia, during February and March 2009. There was marked variability in laboratory diagnostic capacity among the facilities assessed. Of 69 facilities surveyed, 53 provided both comprehensive malaria laboratory diagnosis and outpatient treatment services, five provided malaria microscopy services (referring elsewhere for treatment), and 11 primary care health posts provided rapid diagnostic testing and outpatient malaria treatment. The facilities' median catchment population was 39, 562 and 3581 people for secondary/tertiary and primary health facilities, respectively. Depending on facility type, facilities provided services 24 hrs a day, had inpatient capacity, and access to water and electricity. Facilities were staffed by general practitioners, health officers, nurses or health extension workers. Of the 58 facilities providing laboratory services, 24% of the 159 laboratory staff had received malaria microscopy training in the year prior to this survey, and 72% of the facilities had at least one functional electric binocular microscope. Facilities had variable levels of equipment, materials and biosafety procedures necessary for laboratory diagnosis of malaria. The mean monthly number of malaria blood films processed at secondary/tertiary facilities was 225, with a mean monthly 56 confirmed parasitologically. In primary facilities, the mean monthly number of clinical malaria cases seen was 75, of which 57 were tested by rapid diagnostic test (RDTs). None of the surveyed laboratory facilities had formal quality assurance/quality control protocols for either microscopy or RDTs. This is the first published report on malaria diagnostic capacity in Ethiopia. While our assessment indicated that malaria laboratory diagnosis was available in most facilities surveyed, we observed significant gaps in laboratory services which could significantly impact quality and accessibility of malaria diagnosis, including laboratory infrastructure, equipment, laboratory supplies and human resources.

This report presents the geochemical data, quality assurance and quality control (QA/QC) results of the re-analysis of lake sediment samples collected from north-central Saskatchewan (NTS 074-A, B, G and H). The original lake survey was conducted in 1986 and the re-analysis in 2021. Original survey results are presented in OF1359. A total of 1,290 lake sediment samples were re-analyzed, covering an area of 17,000 km2, averaging a density of 1 sample per 13 km2. Samples were measured for 65 elements via modified aqua-regia - ICP-MS and 35 elements via INA analysis. To ensure high quality data, the geochemical data was evaluated for contamination, accuracy, precision and fitness-for-purpose. QA/QC results have identified a number of elements to be monitored carefully for future analyses. Overall, the data are of good quality.

Treatments for skin injuries have recently advanced tremendously. Such treatments include allogeneic and xenogeneic transplants and skin substitutes such as tissue-engineered skin, cultured cells, and stem cells. The aim of this paper is to discuss the general overview of the quality assurance and quality control implemented in the manufacturing of cell and tissue product, with emphasis on our experience in the manufacturing of MyDerm®, an autologous bilayered human skin substitute. Manufacturing MyDerm® requires multiple high-risk open manipulation steps, such as tissue processing, cell culture expansion, and skin construct formation. To ensure the safety and efficacy of this product, the good manufacturing practice (GMP) facility should establish a well-designed quality assurance and quality control (QA/QC) programme. Standard operating procedures (SOP) should be implemented to ensure that the manufacturing process is consistent and performed in a controlled manner. All starting materials, including tissue samples, culture media, reagents, and consumables must be verified and tested to confirm their safety, potency, and sterility. The final products should also undergo a QC testing series to guarantee product safety, efficacy, and overall quality. The aseptic techniques of cleanroom operators and the environmental conditions of the facility are also important, as they directly influence the manufacturing of good-quality products. Hence, personnel training and environmental monitoring are necessary to maintain GMP compliance. Furthermore, risk management implementation is another important aspect of QA/QC, as it is used to identify and determine the risk level and to perform risk assessments when necessary. Moreover, procedures for non-conformance reporting should be established to identify, investigate, and correct deviations that occur during manufacturing. This paper provides insight and an overview of the QA/QC aspect during MyDerm® manufacturing in a GMP-compliant facility in the Centre for Tissue Engineering and Regenerative Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia.

To inform mitigation strategies and understand how microplastics affect wildlife, research is focused on understanding the sources, pathways, and occurrence of microplastics in the environment and in wildlife. Microplastics research entails counting and characterizing microplastics in nature, which is a labor-intensive process, particularly given the range of particle sizes and morphologies present within this diverse class of contaminants. Thus, it is crucial to determine appropriate sampling methods that best capture the types and quantities of microplastics relevant to inform the questions and objectives at hand. It is also critical to follow protocols with strict quality assurance and quality control (QA/QC) measures so that results reflect accurate estimates of microplastic contamination. Here, we assess different sampling procedures and QA/QC strategies to inform best practices for future environmental monitoring and assessments of exposure. We compare microplastic abundance and characteristics in surface-water samples collected using different methods (i.e., manta and bulk water) at the same sites, as well as duplicate samples for each method taken at the same site and approximate time. Samples were collected from 9 sampling sites within San Francisco Bay, California, USA, using 3 different sampling methods: 1) manta trawl (manta), 2) 1-L grab (grab), and 3) 10-L bulk water filtered in situ (pump). Bulk water sampling methods (both grab and pump) captured more microplastics within the smaller size range (<335 µm), most of which were fibers. Manta samples captured a greater diversity of morphologies but underestimated smaller-sized particles. Inspection of pump samples revealed high numbers of particles from procedural contamination, stressing the need for robust QA/QC, including sampling and analyzing laboratory blanks, field blanks, and duplicates. Choosing the appropriate sampling method, combined with rigorous, standardized QA/QC practices, is essential for the future of microplastics research in marine and freshwater ecosystems. Integr Environ Assess Manag 2021;17:282-291. © 2020 SETAC.

Simple SummaryStandardization of flow-cytometric assessment of minimal residual disease in acute lymphoid leukemia (ALL) is necessary to allow concordant multicentric application of the methodology. This is a prerequisite for internationally collaborative trials, such as the AIEOP-BFM-ALL and the ALL IC-BFM trial. We developed and applied a comprehensive training and quality control program involving a large number of international laboratories within the I-BFM consortium to complement standardization of the methodology with an educational component as well as with persistent quality control measures to allow large ALL treatment trials which use multi-laboratory FCM-MRD assessments for risk stratification of pediatric patients with ALL.Monitoring of minimal residual disease (MRD) by flow cytometry (FCM) is a powerful prognostic tool for predicting outcomes in acute lymphoblastic leukemia (ALL). To apply FCM-MRD in large, collaborative trials, dedicated laboratory staff must be educated to concordantly high levels of expertise and their performance quality should be continuously monitored. We sought to install a unique and comprehensive training and quality control (QC) program involving a large number of reference laboratories within the international Berlin-Frankfurt-Münster (I-BFM) consortium, in order to complement the standardization of the methodology with an educational component and persistent quality control measures. Our QC and quality assurance (QA) program is based on four major cornerstones: (i) a twinning maturation program, (ii) obligatory participation in external QA programs (spiked sample send around, United Kingdom National External Quality Assessment Service (UK NEQAS)), (iii) regular participation in list-mode-data (LMD) file ring trials (FCM data file send arounds), and (iv) surveys of independent data derived from trial results. We demonstrate that the training of laboratories using experienced twinning partners, along with continuous educational feedback significantly improves the performance of laboratories in detecting and quantifying MRD in pediatric ALL patients. Overall, our extensive education and quality control program improved inter-laboratory concordance rates of FCM-MRD assessments and ultimately led to a very high conformity of risk estimates in independent patient cohorts.

Quality assurance and quality control (QA/QC) procedures for mineralogy, porosity, and texture analyses of fine-grained carbonate rocks using automated quantitative mineralogy combined with scanning electron microscopy (AQM-SEM)

The sound absorption of a road pavement depends not only on geometric and volumetric factors but also on pore shape factors. In turn, pore shape factors mainly refer to thermal and viscous factors (i.e., thermal and viscous effects that usually occur inside porous materials). Despite the presence of a number of studies and researches, there is a lack of information about how to predict or estimate pore shape factors. This greatly affects mixture design, where a physical-based or correlation-based link between volumetrics and acoustics is vital and plays an important role also during quality assurance and quality control (QA/QC) procedures. Based on the above, the objective of this study is to link mixture volumetrics and pore shape factors. In particular, 10 samples of a porous asphalt concrete were tested in order to estimate their thickness, air voids content (vacuum-sealing method, ASTM D6857/D6857M), sound absorption coefficient (Kundt’s tube, ISO 10354-2), airflow resistivity (ISO 9053-2), and permeability (ASTM PS 129). Subsequently, two models (herein called STIN and JCAL) were used to derive both volumetrics and pore shape factors from the estimated parameters listed above, and statistical analysis was carried out to define correlations among the parameters and models performance. Results confirm the complexity of the tasks and point out that estimates of the pore shape factors can be derived based on mixture volumetrics. Results can benefit researchers (in acoustic and pavement mixtures) and practitioners involved in mix design and pavement acceptance processes.

To review a quality control and quality assurance (QC/QA) model established to ensure the validity and reliability of collection, storage and analysis of biological outcome data, and to promote good laboratory practices (GLPs) and sustained operational improvements in international clinical laboratories, we conducted a two-arm randomized community-level HIV behavioural intervention trial in five countries: China, India, Peru, Russia and Zimbabwe. The trial was based on diffusion theory utilizing a Community Popular Opinion Leaders (CPOLs) intervention model with behavioural and biological outcomes. The QC/QA model was established by the Biological Outcome Workgroup, which collaborated with the Data Coordinating Center and John Hopkins University Reference Laboratory. Five international laboratories conducted chlamydia/gonorrhoea polymerase chain reaction (PRC)-based assays, herpes simplex virus type 2 enzyme immunoassay (EIA), syphilis serology (rapid plasma regain and Treponema pallidum particle agglutination assay, HIV serology (EIA/Western blot) and Trichomonas vaginalis culture. Data were collected at baseline, 12 and 24 months. Laboratory performance and infrastructure improved throughout the trial. Recommendations for improvement were consistently followed. Quality laboratories in resource-poor settings can be established, operating standards can be improved and certification can be obtained with consistent training, monitoring and technical support. Building collaborative partnership relations can establish a sustainable network for clinical trials, and can lead to accreditation and international laboratory development.

Hot mix asphalt mat density data collected during the 1990–1993 implementation of a quality control and quality assurance (QC/QA) program for pavement construction by the Alabama Highway Department (AHD) were analyzed. The influence of different measuring agencies (buyer and seller), mix type, application rate, and overlay interface conditions on the variability of nuclear gage and core density measurements was studied. The data were also used to study the influence of the several measurement variables on the ability to achieve target density. Variability and the ability to achieve target density improved as the QC/QA program was implemented, but there remained a consistent inability to achieve the target compaction level. Analysis of the significance of differences between AHD and contractor measurements was inconclusive, but AHD density measurements were consistently lower. Thicker binder mix layers had lower variability than thinner surface mix layers, but the level of compaction achieved was greater for surface mixes. Milling of the surfaces of old pavements significantly reduced the variability of density in overlay mats.

Reference materials (RMs) are vital tools in the validation of methods used to detect environmental pollutants. Microplastics, a relatively new environmental pollutant, require a variety of complex approaches to address their presence in environmental samples. Both interlaboratory comparison (ILC) studies and RMs are essential to support the validation of methods used in microplastic analysis. Presented here are results of quality assurance and quality control (QA/QC) performed on two types of candidate microplastic RMs: dissolvable gelatin capsules and soda tablets. These RMs have been used to support numerous international ILC studies in recent years (2019–2022). Dissolvable capsules containing polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene (PE), and polystyrene (PS), in different size fractions from 50 to 1000 µm, were produced for one ILC study, obtaining relative standard deviation (RSD) from 0 to 24%. The larger size fraction allowed for manual addition of particles to the capsules, yielding 0% error and 100% recovery during QA/QC. Dissolvable capsules were replaced by soda tablets in subsequent ILC studies and recovery test exercises because they were found to be a more reliable carrier for microplastic RMs. Batches of soda tablets were produced containing different single and multiple polymer mixtures, i.e., PE, PET, PS, PVC, polypropylene (PP), and polycarbonate (PC), with RSD ranging from 8 to 21%. Lastly, soda tablets consisting of a mixture of PE, PVC, and PS (125–355 µm) were produced and used for recovery testing during pretreatment of environmental samples. These had an RSD of 9%. Results showed that soda tablets and capsules containing microplastics >50 µm could be produced with sufficient precision for internal recovery tests and external ILC studies. Further work is required to optimize this method for smaller microplastics (< 50 µm) because variation was found to be too large during QA/QC. Nevertheless, this approach represents a valuable solution addressing many of the challenges associated with validating microplastic analytical methods.

Background: Ensuring the validity of results from funded programs is a critical concern for agencies that sponsor biological research. In recent years, the open science movement has sought to promote reproducibility by encouraging sharing not only of finished manuscripts but also of data and code supporting their findings. While these innovations have lent support to third-party efforts to replicate calculations underlying key results in the scientific literature, fields of inquiry where privacy considerations or other sensitivities preclude the broad distribution of raw data or analysis may require a more targeted approach to promote the quality of research output. Methods: We describe efforts oriented toward this goal that were implemented in one human performance research program, Measuring Biological Aptitude, organized by the Defense Advanced Research Project Agency's Biological Technologies Office. Our team implemented a four-pronged independent verification and validation (IV&V) strategy including 1) a centralized data storage and exchange platform, 2) quality assurance and quality control (QA/QC) of data collection, 3) test and evaluation of performer models, and 4) an archival software and data repository. Results: Our IV&V plan was carried out with assistance from both the funding agency and participating teams of researchers. QA/QC of data acquisition aided in process improvement and the flagging of experimental errors. Holdout validation set tests provided an independent gauge of model performance. Conclusions: In circumstances that do not support a fully open approach to scientific criticism, standing up independent teams to cross-check and validate the results generated by primary investigators can be an important tool to promote reproducibility of results.

Microplastics: Human exposure assessment through air, water, and food