Search

The main factor restricting lead isotope analysis of metals from museum collections is the requirement for physical material. Hence, there are major incentives for developing minimally invasive methods for lead isotope analysis that are accurate and precise enough to reveal historical information about artefacts and their origin. Portable laser ablation (pLA), collecting microscopic samples on Teflon filters, has four key benefits. It produces no visual impact to the artefacts, does not require transport of artefacts to laboratory facilities, there are no artefact size restrictions, and samples are processed under clean laboratory conditions allowing Pb purification prior to measurement by solution MC-ICPMS. To validate the efficacy of the pLA technique on silver, nine matrixed-matched commercial, in-house and archaeological reference materials were sampled and analysed multiple times (9-10). The pLA mean analyses (±2SD) were all consistent with inter-laboratory bulk analyses. The digestion of sample filters produces precisions that are consistently more than five-times better than in situ nsLA-MC-ICPMS and are the same order of magnitude expected for bulk samples processed in different laboratories. This journal is

A standardized source of light is essential for visual color assessments, which is why lighting booths were developed. For the best results in visual assessment, it is important to consider the right choice of light source, the right viewing conditions, and the variability of the viewer. To date, many light booth technologies have been introduced to meet user demands. Since most of the light sources on the market are characterized by the designer or manufacturer, the resulting variations from booth-to-booth remain. In this study, we compared the performance of two standard light booths to assess the color difference of eleven metameric pairs. In this study, we checked an earlier technology-based light booth that is still used in the textile industry and contains illuminant A (Tungsten lamp) with CCT 2700 K, TL84 (tri-band fluorescent tube) with CCT 4000 K, and simulator D65 (CCT 6500 K) with a different light booth whose original light sources have been replaced by currently available LED retro kits from equivalent CCTs. As an inexperienced customer or industrial user, our question was, how important is this replacement? The results revealed that two different standard lighting technologies with similar CCTs cannot reproduce the same estimates because the light sources produced different SPDs. It is illustrating that caution is necessary when comparing results obtained from two different light booths containing light sources with similar CCTs but different SPDs. This comparative study suggested that the variability of the light sources’ SPDs or the observer or the sample should be modeled considering light booth’s technology to estimate its contribution to the overall variability. The close relationship between perceived and CAM02-UCS suggests that if both booths are used after the light sources have been calibrated, a formula based on color appearance models must be used to predict color appearance. To obtain better agreement between perceived and calculated color difference, one must need to avoid light booths with nominally white light sources.

Background Multi-sample comparison is commonly used in cancer genomics studies. By using next-generation sequencing (NGS), a mutation's status in a specific sample can be measured by the number of reads supporting mutant or wildtype alleles. When no mutant reads are detected, it could represent either a true negative mutation status or a false negative due to an insufficient number of reads, so-called "coverage". To minimize the chance of false-negative, we should consider the mutation status as "unknown" instead of "negative" when the coverage is inadequately low. There is no established method for determining the coverage threshold between negative and unknown statuses. A common solution is to apply a universal minimum coverage (UMC). However, this method relies on an arbitrarily chosen threshold, and it does not take into account the mutations' relative abundances, which can vary dramatically by the type of mutations. The result could be misclassification between negative and unknown statuses. Methods We propose an adaptive mutation-specific negative (MSN) method to improve the discrimination between negative and unknown mutation statuses. For a specific mutation, a non-positive sample is compared with every known positive sample to test the null hypothesis that they may contain the same frequency of mutant reads. The non-positive sample can only be claimed as “negative” when this null hypothesis is rejected with all known positive samples; otherwise, the status would be “unknown”. Results We first compared the performance of MSN and UMC methods in a simulated dataset containing varying tumor cell fractions. Only the MSN methods appropriately assigned negative statuses for samples with both high- and low-tumor cell fractions. When evaluated on a real dual-platform single-cell sequencing dataset, the MSN method not only provided more accurate assessments of negative statuses but also yielded three times more available data after excluding the “unknown” statuses, compared with the UMC method. Conclusions We developed a new adaptive method for distinguishing unknown from negative statuses in multi-sample comparison NGS data. The method can provide more accurate negative statuses than the conventional UMC method and generate a remarkably higher amount of available data by reducing unnecessary “unknown” calls.

Objective To figure out the source of uncertainty in the determination of 14C activity concentration in urine samples, and to establish a complete expression of analysis results, in order to improve the accuracy of 14C monitoring method. Methods Four urine samples of normal people were collected, and wet oxidation method was used in the pretreatment of the samples, then the activity concentration of 14C was determined by liquid scintillation counting (LSC). After the mathematical model was established, the uncertainty components were determined, the standard uncertainty was combined, and the extended uncertainty was calculated. Results The relative uncertainty of 4 samples was 22.5%, 17.0%, 17.3% and 18.2%. The activity concentration of urine was (0.32 ​± ​0.14), (0.60 ​± ​0.20), (0.86 ​± ​0.30) and (0.74 ​± ​0.27) Bq/L, respectively. In the relative uncertainty of 22.5%, 17.7% was from sample counting, 13.6% from detection efficiency, 2.1% from recovery rate, 0.58% from sample volume, and 0.01% from sample weight. Conclusions The main factors affecting the uncertainty include the error or deviation of sample counting, detection efficiency and recovery rate. The error of volume and weight also contributes to the measurement uncertainty.

Abstract Cinnabar (α-HgS) is a common mineral used in various fields. The identification of cinnabar can be achieved by classic mineralogical methods and instrumental methods. X-ray diffraction (XRD) is the most reliable instrumental method for identifying material phases, but the sampling process and the immovable instrument limit its wider application in the cultural heritage field. The occurrence of Assing S. p. A. Surface Monitor, a portable system integrating X-ray fluorescence (XRF) and XRD, provides researchers with a new solution. Raw mineral, polished gemstone, pigment powder and Chinese ink stick claimed to be composed of cinnabar were measured by the system as well as laboratory-type XRD and micro-Raman techniques in this study. The qualitative XRF results were applied to determining the elements existing in the samples and thus defining the range of possible phases. Patterns obtained were compared carefully with the characteristic lines to determine the most likely phases, while the pattern appearances were compared in order to recognize the different states of cinnabar and generalize the experience for identifying cinnabar by the system. The Raman spectra obtained were compared and analyzed in order to learn the best parameters and determine the real composition of each sample. The results indicate that the XRF detector is sensitive enough to distinguish cinnabar from another red pigment, minium (Pb3O4), without destructive preparation provided that the desired phases occupy a major content in the sample, while the laser micro-Raman is even better in application range and measurement speed but correct analysis of the spectra is highly dependent on experience and literatures. The portable coupled XRF-XRD system and the micro-Raman provide researchers with convenient and efficient options to preliminarily identify minerals like cinnabar, which is significantly meaningful to several research fields including mineralogy, heritage science, material science, etc. Article highlights Two efficient and non-destructive methods for the preliminary identification of minerals like cinnabar were developed. The optimum instrument parameters for the effective measurement of different cinnabar samples were given in detail. The study provides useful data for various fields including analytical science, material science, heritage science, etc.

Background Artificial intelligence can assist in cardiac image interpretation. Here, we achieved a substantial reduction in time required to read a cardiovascular magnetic resonance (CMR) study to estimate left atrial volume without compromising accuracy or reliability. Rather than deploying a fully automatic black-box, we propose to incorporate the automated LA volumetry into a human-centric interactive image-analysis process. Methods and results Atri-U, an automated data analysis pipeline for long-axis cardiac cine images, computes the atrial volume by: (i) detecting the end-systolic frame, (ii) outlining the endocardial borders of the LA, (iii) localizing the mitral annular hinge points and constructing the longitudinal atrial diameters, equivalent to the usual workup done by clinicians. In every step human interaction is possible, such that the results provided by the algorithm can be accepted, corrected, or re-done from scratch. Atri-U was trained and evaluated retrospectively on a sample of 300 patients and then applied to a consecutive clinical sample of 150 patients with various heart conditions. The agreement of the indexed LA volume between Atri-U and two experts was similar to the inter-rater agreement between clinicians (average overestimation of 0.8 mL/m2 with upper and lower limits of agreement of − 7.5 and 5.8 mL/m2, respectively). An expert cardiologist blinded to the origin of the annotations rated the outputs produced by Atri-U as acceptable in 97% of cases for step (i), 94% for step (ii) and 95% for step (iii), which was slightly lower than the acceptance rate of the outputs produced by a human expert radiologist in the same cases (92%, 100% and 100%, respectively). The assistance of Atri-U lead to an expected reduction in reading time of 66%—from 105 to 34 s, in our in-house clinical setting. Conclusions Our proposal enables automated calculation of the maximum LA volume approaching human accuracy and precision. The optional user interaction is possible at each processing step. As such, the assisted process sped up the routine CMR workflow by providing accurate, precise, and validated measurement results.

All banknotes have security features which are intended to help determine whether they are false or genuine. Typically, however, the general public has limited knowledge of where on a banknote these security features can be found. Here, we tested whether counterfeit detection can be improved with the help of salient elements, designed to guide bottom-up visuospatial attention. We also tested the influence of the participant’s a priori level of trust in the authenticity of the banknote. In an online study (N = 422), a demographically diverse panel of Dutch participants distinguished genuine banknotes from banknotes with one (left- or right-sided) counterfeited security feature. Either normal banknotes (without novel design elements) or banknotes that contained a salient element (a pink rectangular frame) were presented for 1 s. To manipulate the participant’s level of trust, trials were administered in three blocks, whereby at the start of each block, participants were instructed that either one third, one half, or two thirds of the upcoming banknotes were counterfeit (though the true ratio was always 1:1). We hypothesized (i) that in the presence of a salient element, counterfeits would be better detected when the location of the salient element aligned with the location of the counterfeited security feature—i.e. that it would act as an attentional cue; and (ii) that this effect would be stronger with lower trust. Our hypotheses were partly confirmed: counterfeit detection improved with ‘valid cues’ and decreasing trust, but the level of trust did not modulate the cueing effect. As the overall detection performance was rather poor, we replicated the study with a sample of university students (N = 66), this time presenting stimuli until response. While indeed observing better overall performance, all other patterns were replicated. Our results provide evidence that attention can be guided to enhance banknote authentication.

Water consumed is stored in several water bodies in and around us, out of which dams accommodate a major portion of water. The quantity and quality monitoring of water in dams is troublesome due to their large surface area and high depths. Although groundwater resources are the primary water source in India, dams plays a vital role in water distribution and storage network. The Central Water Commission in India has identified more than 5,000 dams of which a major portion is persistently consumed by the rural and urban populations for drinking and irrigation. The water quality of these reservoirs is of serious concern as it would not only affect the socio-economic status of the nation but the aquatic systems as well. Water quality control and management are vital for a delivering clean water supply to the general society. Because of their size, collecting, assessing, and managing a vast volume of water quality data are critical. Water quality data are primarily obtained through manual field sampling; however, real-time sensor monitoring is increasingly being used for more efficient data collection. The literature depicts that the methods involving remote sensing and image processing of water quality analysis consume time, and require sample collection at various depths, analysis of collected samples, and manual interpretations. The objective of this study was to propose a novel cost-effective method to monitor water quality devoid of considerable human intervention. Sensor-based online monitoring aids in assessing the sample with limited technology, at various depths of water in the dam to analyze turbidity which gives the major indication of pure water. The quality analysis of the dam water is suitable if the water is assessed at the distribution end before consumption. Hence, to enhance the water management system, other quality parameters like pH, conductivity, temperature are sensed and monitored in the distribution pipeline. An unstable pH can alter the chemical and microbiological aspects of water, resulting in a variation of other water quality parameters. Temperature variations affect the amount of dissolved oxygen in the water bodies and results in unstable quality parameters. The change in dissolved solvents and the ionic concentration alters the electrical conductivity of the water and the increased concentration of salts also results in turbidity. The data from all the sensors are processed by the microcontroller, transmitted, and displayed in a mobile application comprehensible to the layman. HIGHLIGHTS The quantity and quality monitoring of water in dams is troublesome due to their large surface area and high depths.; An effective quality analysis is the demand of the hour and the problem statement is identified in developing a system to check water quality at various depths in a dam.; An efficient pipeline with various sensors which monitor turbidity, pH, and conductivity is developed as a prototype low cost device.

Background The Quality of Life Impact Refractive Correction (QIRC) questionnaire is a Rasch-validated instrument to assess the quality of life of ametropes with refractive correction. The original QIRC was validated in the United Kingdom. This study aimed to validate the Malay version of the QIRC among refractive correction wearers in Malaysia using Rasch analysis. Methods The original 20-item QIRC was forward-backward translated into Malay in preparation for the Pilot Malay QIRC. The pilot version was pre-tested on 105 spectacle/contact lens-corrected myopes, and the results were reviewed and cross-culturally adapted to produce the Final Malay QIRC. The final version was self-administered to a new sample of 304 participants. A Rasch analysis was conducted to evaluate the items and response categories of the Pilot and the Final Malay QIRC. Test-retest reliability was also analysed on the Final Malay QIRC. Results Based on the pre-test findings, Rasch analysis revealed a multidimensional scale (functional scale [Items 1 to 13] and emotional scale [Items 14 to 20], which were separated in subsequent analysis), unordered response categories for the functional scale (Category 3 was collapsed into Category 2), one misfit item (Item 3 was removed) and six items required modification (Items 4, 6 to 9, and 12 were reworded and cross-culturally adapted). In the Final Malay QIRC, both the functional and emotional scales had ordered response categories, good person reliability (functional, 0.80; emotional, 0.81) and separation index (functional, 2.01; emotional, 2.06), well-targeted items (targeting precision: functional, 0.28 logits; emotional, 0.08 logits), and satisfactory fit statistics (infit and outfit mean square were less than 1.50 for all items). A noticeable differential item functioning (DIF) between genders was found in Item 18 (DIF contrast, 0.40 logits; p = 0.04). Test-retest reliability analysis demonstrated a high intraclass correlation coefficient (0.94) and Cronbach’s alpha (0.97) with a coefficient of repeatability of ±8.14 units. Conclusions The Malay-translated version of the QIRC has good psychometric characteristics for assessing the quality of life of refractive correction wearers in Malaysia. This translated and cross-culturally adapted Malay QIRC is a valid and reliable instrument that can be used in routine clinical practice.

Efforts have been devoted to screening various prevalent diseases, such as severe acute respiratory syndrome (SARS) and coronavirus disease 2019 (COVID-19). Real-time polymerase chain reaction (RT-PCR), which is currently the most widely used, has high accuracy, but it requires several facilities and takes a relatively long time to check; so, new testing technology is necessary for a higher test efficiency. A chemiluminescence (CL) sensor is a relatively simple device and suitable as an alternative because it can detect very precise specimens. However, in measurements via CL, the quantitative formulation of reagents that cause color development is important. In the case of mixing using micropipettes, precise analysis is possible, but this technique is limited by uncontrollable errors or deviations in detection amounts. In addition, in using a microfluidic chip to increase field applicability, a syringe pump or other quantification injection tools are required, so problems must be overcome for practical use. Therefore, in this study, a microchip was designed and manufactured to supply a sample of a certain volume by simply blowing air and injecting a sample into the chamber. By utilizing the luminescence reaction of luminol, CuSO4 and H2O2 the performance of the prepared chip was confirmed, and the desired amount of the sample could be injected with a simple device with an error rate of 2% or less. For feasible applications, an experiment was performed to quantitatively analyze thrombin, a biomarker of heart disease. Results demonstrated that biomarkers could be more precisely detected using the proposed microchips than using micropipettes.

Background The detection of SARS-CoV-2 using qRT-PCR with the pooling of samples can reduce workload and costs especially when the prevalence rate of COVID-19 in a population is low. To analyse the effect of pooling samples on the sensitivity of RT-qPCR for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection, we compared the cycle threshold (Ct) values of pools of 5 and 10 that tested positive with Ct values of individual samples that tested positive in that pool. Twenty positive nasopharyngeal (NP) specimens with low to high viral load were selected and pooled individually with four and nine negative NP. Results In NP specimens, the sensitivity of pools of 5 and 10 were 90 and 85%, compared to individual sample testing, respectively. The RT-qPCR sensitivity of pools of 5 and 10 against individual testing were not significantly different (p > 0.05). Detection of positive samples with low Ct values ( 36) were pooled and tested. The mean Ct values obtained with the 5-sample pooled testing exceeded individual sample testing by 1.85 ± 1.09 cycles, while Ct values obtained with the 10-sample pooling exceeded individual sample testing by 3.4 ± 1.65 cycles. Conclusions In a low prevalence setting, testing capacity can be increased by pooling 5 or 10 samples, but the risk of additional false negatives needs to be considered

BackgroundInsecticide-treated nets (ITNs) undergo a series of tests to obtain listing by World Health Organization (WHO) Prequalification. These tests characterize the bioefficacy, physical and chemical properties of the ITN. ITN procurers assume that product specifications relate to product performance. Here, ITN test methods and their underlying assumptions are discussed from the perspective of the ITN manufacturing process and product characteristics.MethodsData were extracted from WHO Pesticide Evaluation Scheme (WHOPES) meeting reports from 2003 to 2017, supplemented with additional chemical analysis to critically evaluate ITNs bioassays with a focus on sampling, washing and wash resistance, and bioefficacy testing. Production methods for ITNs and their impact on testing outcomes are described.Results and recommendationsITNs are not homogenous products. They vary within panels and between the sides and the roof. Running tests of wash resistance using a before/after tests on the same sample or band within a net reduces test variability. As mosquitoes frequently interact with ITN roofs, additional sampling of the roof when evaluating ITNs is advisable because in nets where roof and sides are of the same material, the contribution of roof sample (20–25%) to the average is less than the tolerance for the specification (25%). Mosquito mortality data cannot be reliably used to evaluate net surface concentration to determine regeneration time (RT) and resistance to washing as nets may regenerate beyond the insecticide concentrations needed to kill 100% of susceptible mosquitoes. Chemical assays to quantify surface concentration are needed. The Wash Resistance Index (WRI) averaged over the first four washes is only informative if the product has a log linear loss rate of insecticide. Using a WRI that excludes the first wash off gives more reliable results. Storage conditions used for product specifications are lower than those encountered under product shipping and storage that may exceed 50 °C, and should be reconsidered. Operational monitoring of new ITNs and linking observed product performance, such as bioefficacy after 2 or 3 years of use, with product characteristics, such as WRI, will aid the development of more robust test methods and product specifications for new products coming to market.

Graphical abstract In spite of a rapid growth of data processing software, that has allowed for a huge advancement in many fields of chemistry, some research issues still remain problematic. A standard example of a troublesome challenge is the analysis of multi-component mixtures. The classical approach to such a problem consists of separating each component from a sample and performing individual measurements. The advent of computers, however, gave rise to a relatively new domain of data processing – chemometry – focused on decomposing signal recorded for the sample rather than the sample itself. Regrettably, still a very few chemometric methods are practically used in everyday laboratory routines. The Authors believe that a brief ‘user-friendly’ guide-like article on several ‘flagship’ algorithms of chemometrics may, at least partly, stimulate an increased interest in the use of these techniques among researchers specializing in many fields of chemistry. In the paper, five different techniques of factor analysis are used for the analysis of a three-component system of fluorophores. These algorithms, applied on the excitation-emission spectra, recorded for the ‘unknown’ mixture, allowed to unambiguously determine its composition without the need for physical separation of the components. An example of using chemometric methods for physical chemistry research is also provided. For each presented technique of the data analysis, a short description of its theoretical background followed by an example of its practical performance is given. In addition, the Reader is supplemented with a basic information on matrix algebra, detailed experimental ‘recipes’, reference specialist literature and ready-to-use MATLAB codes. Supplementary Information The online version contains supplementary material available at 10.1007/s10895-021-02753-w.

As continues increasing the COVID-19 infections, there is an urgent need for developing fast, simple, selective, and accurate COVID-19 biosensors. A highly uniform gold (Au) microcuboid pattern was used as a microelectrode that allowed monitoring a small analyte. The electrochemical biosensor was used to monitor the COVID-19 S protein within a concentration range from 100 to 5 pmol L-1; it showed a lower detection limit of 276 fmol L-1. Finally, the developed COVID-19 sensor was used to detect a positive sample from a human patient obtained through a nasal swab; the results were confirmed using the PCR technique. The results showed that the SWV technique showed high sensitivity towards detecting COVID-19 and good efficiency for detecting COVID-19 in a positive human sample.

This study aims to determine the quality of the mathematics test items at SMKN 3 Kuningan in terms of validity, reliability, differentiation, difficulty level and distractor effectiveness. This research is an evaluation type research with a quantitative approach. The population in this study were all the items contained in the mathematics module book for class XI SMKN 3 Kuningan, while the sample was 30 multiple choice questions taken in each chapter. The results showed that the majority (96.67%) of the items were declared valid in content by the experts. The test has very high reliability (0.90). The items have the ideal difficulty level. Most of the questions (70%) had medium difficulty, a few questions (6.67%) were very easy and a few questions (20%) were difficult and (3.3%) were very difficult. Most of the items (83.33%) had good distinguishing power and only a few questions (16.67%) had poor distinguishing power. Most (90%) of the questions had a well-functioning answer choice and only a few questions (10%) had the answer choice not functioning properly. Overall, this study can be concluded that the Mathematics Test Questions at SMKN 3 Kuningan are of good quality.

Recent global events have distinctly demonstrated the need for fast diagnostic analysis of targets in a liquid sample. However, microfluidic lab-on-a-chip devices for point-of-care diagnostics can suffer from slow analysis due to poor mixing. Here, we experimentally explore the mixing effect within a microfluidic chamber, as obtained from superparamagnetic beads exposed to an out-of-plane (vertical) rotating magnetic field. Various magnetic protocols are explored, and the level of sample homogeneity is measured by determining the mixing efficiency index. In particular, we introduce a method to induce effective mixing in a microfluidic chamber by the actuation of the same beads to perform global swarming behavior, a collective motion of a large number of individual entities often seen in nature. The microparticle swarming induces high fluid velocities in initially stagnant fluids, and it can be externally controlled. The method is pilot-tested using a point-of-care test featuring a bioluminescent assay for the detection of antibodies. The mixing by the magnetic beads leads to increased assay kinetics, which indeed reduces the time to sensor readout substantially. Magnetic microparticle swarming is expected to be beneficial for a wide variety of point-of-care devices, where fast homogeneity of reagents does play a role.

Background: Determine the exact slot dimension of a sample of a MBT prescription stainless steel conventional brackets from different manufacturers to compare the actual values with the nominal ones declared by the manufacturers and to verify the compliance with tolerance limits given by the ISO 27020:2019. Different batches from each manufacturer were evaluated to determine whether or not they are different in size. In addition, the geometry of the slot walls was assessed. Methods: 360 stainless steel preadjusted orthodontic brackets of 12 different manufacturers were assessed. All brackets had a nominal slot size of 0.022 by 0.028 inches, belonged to the right upper central incisor, and were fabricated with the metal injection molding technique (MIM). For each manufacturer, three different manufacturing batches were evaluated. Brackets were coded using a single-blind design. Results: All bracket systems in the study group except one displayed a statistically significant difference with the nominal declared value, although only four of the systems did not comply with the tolerance limits established by the ISO 27020:2019. In most of the systems, the slot height was oversized when compared to the nominal one. A significant interbatch variability was found in most of the evaluated systems. Most of the brackets walls were divergent. Conclusions: The dimensional accuracy of commercially available metal brackets is not guaranteed. The respect for the norm should be enforced as well as the quality controls along the manufacturing process since orthodontic brackets are a precision medical device. Objetivos: Determinar la dimensión exacta del slot de una muestra de brackets convencionales de acero inoxidable recetados MBT de diferentes fabricantes para comparar los valores reales con los nominales declarados por los fabricantes y verificar el cumplimiento de los límites de tolerancia dados por la norma ISO 27020:2019. Se evaluaron diferentes lotes de cada fabricante para determinar si eran o no de tamaño diferente. Además, se evaluó la geometría de las paredes de las ranuras. Métodos: Se evaluaron 360 brackets de ortodoncia preajustados de acero inoxidable de 12 fabricantes diferentes. Todos los brackets tenían un tamaño de ranura nominal de 0.022 por 0.028 pulgadas, pertenecían al incisivo central superior derecho y fueron fabricados con la técnica de moldeo por inyección de metal (MIM). Para cada fabricante se evaluaron tres lotes de fabricación diferentes. Los corchetes se codificaron utilizando un diseño simple ciego. Resultados: Todos los sistemas de brackets del grupo de estudio excepto uno presentaron una diferencia estadísticamente significativa con el valor nominal declarado, aunque solo cuatro de los sistemas no cumplieron con los límites de tolerancia establecidos por la norma ISO 27020:2019. En la mayoría de los sistemas, la altura de la ranura estaba sobredimensionada en comparación con la nominal. Se encontró una importante variabilidad entre lotes en la mayoría de los sistemas evaluados. La mayoría de las paredes de los soportes eran divergentes. Conclusiones: No se garantiza la precisión dimensional de los brackets metálicos disponibles en comercio. Se debe hacer cumplir el respeto a la norma y los controles de calidad a lo largo del proceso de fabricación ya que los brackets de ortodoncia son un dispositivo médico de precisión. Sin financiación 2.151 JCR (2020) Q3, 58/92, Dentistry, Oral Surgery & Medicine 0.620 SJR (2020) Q2, 47/141 Dentistry (miscellaneous) No data IDR (2020) UEV

Rising temperature will cause the changes of pore characteristics and strength property in rock. This research takes the limestone produced in Taihang Mountains as the research object, and performs high-temperature treatment within 25–1000 °C. The high-resolution X-ray computed tomography (CT) scanning test method is used to visually reconstruct the three-dimensional image of the sample, and obtain the spatial distribution status of the mesoscopic parameters of the bones, pores/cracks, etc. The results show that when the temperature exceeded 700 °C, the samples appeared milky white in appearance and as the temperature increased, the color gradually turned white, macroscopic cracks began to appear on the surface, while the meso-pores connected rapidly, reflecting a typical progressive destruction process from inside to outside. The change law of volume porosity with temperature has a consistent trend with that of the apparent morphology of the sample. Similarly, the mechanical test results suggest that 700 °C is also the turning temperature for strength deterioration and brittle-plastic transformation of sample. Based on the results of high-temperature test, CT test and mechanical test, there are enough evidences to show that, for the limestone sample, 700 °C is probably to be the mutation temperature of physical–mechanical behavior.

Background Central venous access devices (CVAD) are an essential part of safe practices in critical care, which enable effective venous access and help in avoiding repeated venipuncture. Discard method is widely practiced for blood sampling. A single occasion of blood sampling may cause minimal blood loss; however, the cumulative volume sequential sampling may become clinically significant. The study aims to reduce diagnostic blood loss, ensuring that the subsequent blood sample is not diluted or contaminated by residual intraluminal fluid. Patients and Methods Within-subjects comparative design was adopted for 64 adult patients in the medical intensive care unit of a tertiary hospital. Two blood samples, using 3 mL and 5 mL discarded volume methods, were collected from each patient. Six serum parameters were measured on each of the paired samples and compared. Statistical Analysis Used Paired t-test and Wilcoxon signed rank test were used for comparing the two methods. Bland–Altman plot analysis and intraclass correlation were used for clinically meaningful analysis. Results When tested for fixed bias, there is no statistically significant difference between the methods. Potassium and creatinine levels showed significant proportional bias. The agreement limits of sodium, potassium, creatinine, and direct bilirubin were outside the clinically accepted interval, but the proportion of samples outside these intervals was less than 10%. All serum parameters showed excellent reliability, except for sodium which demonstrated good reliability. Conclusions The practice of discarding 3 mL of blood for discard method is suggested, instead of the standard 5 mL to reduce iatrogenic blood loss. Thus, nurses in critical care are uniquely positioned to limit the diagnostic blood loss while obtaining blood samples.

Currently, emphasis is placed on the efficiency of process technology in the production of energy. Large energy corporations are forced to develop new and optimize existing technologies to reduce emission limits. In coal and biomass combustion technologies, it is important to continually monitor and evaluate the quality of input material. A sampling device is used to obtain a representative sample of the fuel from the continuous conveying process. In this research work, the effect of setting the operating conditions of the rotating sampling device for coal, which is intended for combustion, is investigated. From the operating tests, we found that the different settings of the sampling device (velocity, dimensional parameters) influence the quality and quantity of a representative sample of coal taken from the belt conveyor of the technological line. Keywords: Coal; Sample; Sampling device.

Summary Coronavirus disease (COVID‐19) has spread all across the world. Low‐ and medium‐income countries are more affected economically and socially compared to developed countries due to the lack of a rapid, robust, and affordable testing infrastructure. Furthermore, the high cost of real‐time polymerase chain reaction (PCR) system, sophisticated user‐handling procedure, and high expense of the conventional clinical tests are the root causes of the less accessibility of the testing systems to the users. In this study, a COVID‐19 Point‐of‐Care (POC) ecosystem model is proposed for the low‐ and medium‐income countries (or energy deprived countries) that will facilitate the technological development with locally available fabrication components. In addition, the nontechnological development phases have also been discussed, which encompasses the collaboration among academia, local as well as government bodies, and entrepreneurial ventures. In addition, a hypothetical design of a microfluidic paper‐based analytical (μPADs) POC platform is proposed to detect COVID‐19 analyte using unprocessed patient‐derived saliva, which is a miniaturized form‐factor of conventional real‐time polymerase chain reaction (PCR) technique. The device contains four major reaction zones, which are sample zone, buffer zone, loop‐mediated isothermal amplification (LAMP) Master Mix zone, Ethylenediamine tetraacetic acid (EDTA) zone, and sensor zone. To obtain quicker test results and easier operation, a handheld image acquisition technique is introduced in this study. It is hypothesized that in a remote setting, the proposed design could be used as an initial guideline to develop a POC COVID‐19 testing system, which may be simple, easy‐to‐use, and cost‐effective., A COVID‐19 Point‐of‐Care (POC) model is proposed that will facilitate the technological development with locally available fabrication components. To obtain quicker test results and easier operation, a handheld image acquisition technique is introduced. The proposed design could be used as an initial guideline to develop a POC COVID‐19 system, which may be simple, easy‐to‐use, and cost‐effective.

Objectives In the absence of sample validity testing, a healthcare provider may fail to identify a patient’s adulteration of their urine sample. This study compared different methods for specific gravity (SG), pH, TECO™ Drug Adulteration Test Strip (dipstick) and oxidant assay to explain the differences and also make an informative decision on method selection. Methods Creatinine, SG and pH measurements are essential in sample validity testing. SG and pH automated chemical methods are compared against pH meter method, SG refractometer and dipstick method. Also, oxidant assay was compared against dipstick method. Results SG chemical method agreement with refractometer is 81.9% and with dipstick method is 64.7%. The refractometer method agreement with dipstick method is 66.1%. pH chemical method agreement with pH Meter method is 74.3% and with dipstick method is 81.4%. pH meter method agreement is 85.7% with dipstick method. Results were analysed using Deming regression analysis and F-test. SG chemical method correlated better with refractometer than the dipstick method. Oxidant assay correlated well with dipstick method in detecting adulterants such as pyridinium chlorochromate, nitrite and bleach. Conclusions Varying degrees of differences were seen in the SG and pH measurements. These differences were both method and instrument dependent. The automated chemical methods are recommended alongside oxidant assay for consistency, accuracy and faster turn-around time as part of sample validity testing for drugs of abuse.

Background: effective control of cardiovascular risk factors remains low in most countries and also in Germany. We investigate whether socio-economic status has an impact on the level of medical treatment and control (normalized values) of total cholesterol.Methods: data on blood lipids from 4 892 participants in the last German Health Survey of 1998 are analysed, adjusting for key determinants in logistic regression analyses. Socio-economic status is not determined by educational achievement alone but also including occupation and household income.Results: the actual prevalence of total cholesterol of ≥240 mg/dl was 53.4%. Only 3.6% of prevalent cases are under effective treatment. Less favourable values of total cholesterol and HDL are displayed by males and in lower social groups, while the middle groups are in an intermediate position. Chances to be treated for hypercholesterolemia are significantly less favourable for females (odds ratio (OR) estimate: 0.70) and better for the age bands ≥50 (OR 2.37) and ≥60 (OR 3.57), if a general practitioner is visited (OR 1.77), and if living in Eastern Germany (OR 1.89). However, chances are not significantly different according to social status.Conclusions: statistically significant social group differences cannot be detected at the present low level of effective treatment. This may be different if higher levels of control are achieved.

Isobaric labeling via tandem mass tag (TMT) reagents enables sample multiplexing prior to LC-MS/MS, facilitating high-throughput large-scale quantitative proteomics. Consistent and efficient labeling reactions are essential to achieve robust quantification; therefore, embedded in our clinical proteomic protocol is a quality control (QC) sample that contains a small aliquot from each sample within a TMT set, referred to as "Mixing QC." This Mixing QC enables the detection of TMT labeling issues by LC-MS/MS before combining the full samples to allow for salvaging of poor TMT labeling reactions. While TMT labeling is a valuable tool, factors leading to poor reactions are not fully studied. We observed that relabeling does not necessarily rescue TMT reactions and that peptide samples sometimes remained acidic after resuspending in 50 mM HEPES buffer (pH 8.5), which coincided with low labeling efficiency (LE) and relatively low median reporter ion intensities (MRIIs). To obtain a more resilient TMT labeling procedure, we investigated LE, reporter ion missingness, the ratio of mean TMT set MRII to individual channel MRII, and the distribution of log 2 reporter ion ratios of Mixing QC samples. We discovered that sample pH is a critical factor in LE, and increasing the buffer concentration in poorly labeled samples before relabeling resulted in the successful rescue of TMT labeling reactions. Moreover, resuspending peptides in 500 mM HEPES buffer for TMT labeling resulted in consistently higher LE and lower missing data. By better controlling the sample pH for labeling and implementing multiple methods for assessing labeling quality before combining samples, we demonstrate that robust TMT labeling for large-scale quantitative studies is achievable.

Background The analysis of hair samples for the detection of drugs has become one of the convincing strategies in the field of forensic toxicology. A large number of cases concerning heroin abuse or its byproducts have been documented under the Control of Narcotic Substances Act, 1997, over the past decade. The present study was carried out with an aim to evaluate the primary metabolite of heroin, i.e., 6-monoacetylemorphine (6-MAM), in hair samples of addicts and subjects undergoing rehabilitation, thereafter accessing the success rate of the rehabilitation program at the de-addiction center. Results Hair samples were randomly collected from 20 regular heroin addicts and 20 heroin addicts from their past, from the rehabilitation center, of different age groups. Samples were cleaned, digested, and extracted using an alkaline digestion mediator methyl tertiary butyl ether, followed by quantification of 6-MAM via gas chromatography–mass spectrometry (GC–MS). The mean concentration of 6-MAM in regular heroin addicts detected was 7.80 ng/mg and 2.34 ng/mg in samples of subjects undergoing rehabilitation at the de-addiction center, respectively. Conclusion Traces of 6-MAM in the hair sample of heroin addicts can be efficiently detected days after the last intake of heroin. In addition to that, our findings also give an idea for future evaluating the approximate timeframe for detection of 6-MAM and/or other metabolites of heroin in the hair sample. However, in the future, by carefully analyzing the hair samples that can be taken from rehabilitation centers from target subjects at different time intervals, the exact duration of traceable quantity of 6-MAM can be determined in the hair sample. Finally, it can be concluded that there is a significant success rate of the rehabilitation program at de-addiction centers in connection with dragging the 6-MAM level from the body.

Background New developments in next-generation sequencing technologies and massive data received from this approach open wide prospects for personalised medicine and nutrition studies. Metagenomic analysis of the gut microbiota is paramount for the characterization of human health and wellbeing. Despite the intensive research, there is a huge gap and inconsistency between different studies due to the non-standardised and biased pipeline. Methodical and systemic understanding of every stage in the process is necessary to overcome all bottlenecks and grey zones of gut microbiota studies, where all details and interactions between processes are important. Results Here we show that an inexpensive, but reliable iSeq 100 platform is an excellent tool to perform the analysis of the human gut microbiota by amplicon sequencing of the 16 S rRNA gene. Two commercial DNA extraction kits and different starting materials performed similarly regarding the taxonomic distribution of identified bacteria. DNA/RNA Shield reagent proved to be a reliable solution for stool samples collection, preservation, and storage, as the storage of faecal material in DNA/RNA Shield for three weeks at different temperatures and thawing cycles had a low impact on the bacterial distribution. Conclusions Altogether, a thoroughly elaborated pipeline with close attention to details ensures high reproducibility with significant biological but not technical variations.

Comparing the diagnostic utility of salivary specimen samples with conventional nasopharynx-oropharynx (NP-OP) specimen samples to identify COVID-19 cases by reverse transcription-polymerase chain reaction (RT-PCR). Eighty COVID-19 suspects enrolled for the paired sampling. In addition to conventional sampling, suspects were asked to follow stepwise pictorial instructions for self salivary sampling. Separate nylon swab stick was used for taking the samples from NP-OP and the floor of the oral cavity. The data were analyzed for sensitivity, specificity, concordance of COVID-19 status, and limits of agreement for cycle threshold (ct) values by either method. Forty-nine suspects (61.3%) were males, the mean age was 36.4 years. To determine the diagnostic test performance of the saliva, RT-PCR results of the NP-OP samples were used as the reference standard. Out of 80 suspects, 41 showed positivity by NP-OP swabs and 12 by salivary samples. The salivary samples showed significantly lesser positivity rate. The sensitivity and specificity of salivary samples against conventional reference standards are 24.4%, 94.9% respectively. Concordance of these two types of samples in terms of agreement kappa statistics is estimated as K = 0.252 (0.09–0.42). Median ct values of both the E and ORF1ab gene for the salivary samples were higher compared to the corresponding NP-OP sample. This study showed lesser sensitivity with salivary swab samples as compared to conventional NP-OP sampling for RT-PCR, COVID-19 detection. Hence, we are of opinion that more studies are required to establish the utility of salivary sampling in COVID-19 diagnostics.

In order to preserve the environment from plastic waste, various ways can be done, one solution is to make a brick made from plastic that is the secret fire and use glass as its mixture. Fire-friendly here using the distillation tool is done so that the oil content of the plastic is separate and the plastics produced are more friendly to the flame. The experimental design by using RAL was used to determine the composition of brick making. In determining the composition is fitting done with a test object, a cube-shaped test object with a size of 5x5x5 cm. Maximum of absorbent brick power is 20%, from the processing result then in the sample can be 4th with water absorption of 0.74%. Based on data processing, the total plastic weight for plastic bricks is 12.77%. Then based on the observations that have been made known at a time 5 minutes 23 seconds. The bricks are not distilled, then the brick that has been distilled melted at a time of 17 minutes 40 seconds. Then based on the calculation result can be cost of raw materials amounting to Rp 51,000, labor cost of Rp 38,461, and the overhead variable fee is Rp 25,000. So the total cost per day of Rp 114,461. Then based on 5% margin, brick sale price of Rp 3,000/seed and breakeven point determination or break event point plastic brick 43 seed, and the point of the scan is Rp 99,350.6493.

3D recording of shipwrecks completely buried in seafloor sediments has great potential as an important aspect of maritime archaeological surveys and management. Buried shipwrecks have been recorded directly with seismic 3D Chirp sub-bottom profilers on an experimental basis. This method is, however, expensive, time-consuming and complicated. This article outlines the application of a faster, cheaper, and less complicated method of synthetic 3D recording, which is also less sensitive to weather conditions. It involves the acquisition of a larger number of seismic 2D high-resolution sub-bottom profiles in a dense grid that does not need to be regular. The method is based on the results of survey work conducted in the Akko Harbour area, on the Carmel coast of Israel, which shows that the shape of the hull of a shipwreck can be precisely determined, and that the sedimentary units bounding it can be outlined and interpreted. Based on an interpretation of the shape of the hull, the depth of the structure was measured, and a 3D image of the shipwreck was subsequently generated. Samples of the sub-seafloor were obtained across the area, and the sample located within the area of the mapped shipwreck was found to contain wood fragments and a piece of rope. This article demonstrates that 2D surveying is a viable and cost-effective alternative to 3D surveying that is able to produce good results.

Efforts to contain the spread of SARS-CoV-2 have spurred the need for reliable, rapid, and cost-effective diagnostic methods which can be applied to large numbers of people. However, current standard protocols for the detection of viral nucleic acids while sensitive, require a high level of automation and sophisticated laboratory equipment to achieve throughputs that allow whole communities to be tested on a regular basis. Here we present Cap-iLAMP (capture and improved loop-mediated isothermal amplification) which combines a hybridization capture-based RNA extraction of gargle lavage samples with an improved colorimetric RT-LAMP assay and smartphone-based color scoring. Cap-iLAMP is compatible with point-of-care testing and enables the detection of SARS-CoV-2 positive samples in less than one hour. In contrast to direct addition of the sample to improved LAMP (iLAMP), Cap-iLAMP prevents false positives and allows single positive samples to be detected in pools of 25 negative samples, reducing the reagent cost per test to ~1 Euro per individual., Current SARS-CoV-2 diagnostic methods are sensitive yet poorly suited to testing whole communities on a regular basis. Here the authors present Cap-iLAMP that tests gargle lavage samples with an improved colorimetric RT-LAMP.

BackgroundThe analysis of the quality of food is important to protect humans from food-borne or food-based illnesses caused by pathogens, such as bacteria, fungi, viruses, and protozoa. Rapid identification of these pathogens is critical to ensure food safety. Various detection and identification strategies exist; however, they are laborious and time consuming and hence the detection takes longer time. The aim of this study was to develop the specific and fast method for the detection of contaminants in milk.ResultsIn this study, we have developed a simple paper-based PCR method with minimum sample preparation process. The 16S rDNA universal primers were used for the detection of bacterial contaminants. LacZ primers were used for coliform detection which causes serious illness and hence their detection is crucial. ITS region primers were used for fungal detection. The most unique thing about this study is use of Whatman paper no. 1 as sample carrier material. We developed and validated the paper-based PCR method and used it for the detection of microbes and coliforms using milk as a representative sample.ConclusionWe evaluated this method for its suitability in the detection of contaminant microbes using different milk samples. The paper-based method could successfully detect contaminants in the milk samples and the results were comparable to the traditional microbial detection method. The traditional microbiological method takes at least 18–20 h for detecting the presence of microbes in any sample but the developed paper-based PCR method can confirm the microbial presence in 2–3 h. This is very promising especially in the testing where sample sterility is crucial.

In pathology protocols, a tissue block, such as one containing a mouse brain or a biopsy sample from a patient, can produce several hundred thin sections. Substantial time may be required to analyse all sections. In cases of uncertainty regarding which sections to focus on, noninvasive scout imaging of intact blocks can help in guiding the pathology procedure. The scouting step is ideally done in a time window of minutes without special sample preparation that may interfere with the pathology procedures. The challenge is to obtain some visibility of unstained tissue structures at sub-10 µm resolution. We explored a novel x-ray tomosynthesis method as a way to maximise contrast-to-noise ratio, a determinant of tissue visibility. It provided a z-stack of thousands of images at 7.3 μm resolution (10% contrast, half-period of 68.5 line pairs/mm), in scans of 5-15 minutes. When compared with micro-CT scans, the straight-line tomosynthesis scan did not need to rotate the sample, which allowed flat samples, such as paraffin blocks, to be kept as close as possible to the x-ray source. Thus, given the same hardware, scan time and resolution, this mode maximised the photon flux density through the sample, which helped in maximising the contrast-to-noise ratio. The tradeoff of tomosynthesis is incomplete 3D information. The microtomosynthesis scanner has scanned 110 unstained human and animal tissue samples as part of their respective pathology protocols. In all cases, the z-stack of images showed tissue structures that guided sectioning or provided correlative structural information. We describe six examples that presented different levels of visibility of soft tissue structures. Additionally, in a set of coronary artery samples from an HIV patient donor, microtomosynthesis made a new discovery of isolated focal calcification in the internal elastic lamina of coronary wall, which was the onset of medial calcific sclerosis in the arteries.A microscopy version of the imaging method for 3D luggage screening has been adapted to image unstained pathology samples. Pathology tests of tissue samples are used for clinical diagnosis and for biomedical research. The tissue samples are often embedded in paraffin blocks and sectioned into many thin slices, which are then stained with the appropriate agents for light microscopy. Since each tissue block can produce several hundred thin sections, much time and labour is required to analyse all sections. Noninvasive scout imaging of intact blocks can help in guiding the pathology procedure. The scouting step is ideally done in a time window of minutes without special sample preparation that may interfere with the pathology procedures. The challenge is to obtain some visibility of unstained tissue structures at sufficient resolution. X-ray imaging is a promising tool to meet the challenge since x-rays can penetrate thick samples that are opaque to visible light. With x-ray imaging, a determinant of tissue visibility is the flux density of photons that illuminate the sample. We explored a novel x-ray tomosynthesis method as a way to maximise this factor. It provided a stack of thousands of cross-sectional images at 7.3 μm resolution (half-period of 68.5 line pairs/mm) in scans of 5-15 minutes. When compared with micro-CT scans (a widely used laboratory technology), this method did not need to rotate the sample, which allowed flat samples such as paraffin blocks to be kept as close as possible to the x-ray source. Thus, given the same hardware, scan time and resolution, this method maximised the photon flux density through the sample, which helped in improving the visibility of unstained tissue under x-ray. The tradeoff of the method is incomplete 3D information. Over 100 unstained human and animal tissue samples have been scanned with this method as part of their respective pathology protocols. In all cases, the stack of cross-sectional images showed tissue structures that guided pathology analysis or provided correlative structural information. We describe six examples that presented different levels of tissue visibility. Additionally, in a set of coronary artery samples from an HIV patient donor, microtomosynthesis made a new discovery of isolated focal calcification in the internal elastic lamina of coronary wall, which was the onset of medial calcific sclerosis in the arteries.

Long-term monitoring of regulated organic chemicals, such as legacy persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs), in ambient air provides valuable information about the compounds' environmental fate as well as temporal and spatial trends. This is the foundation to evaluate the effectiveness of national and international regulations for priority pollutants. Extracts of high-volume air samples, collected on glass fibre filters (GFF for particle phase) and polyurethane foam plugs (PUF for gaseous phase), for targeted analyses of legacy POPs are commonly cleaned by treatment with concentrated sulfuric acid, resulting in extracts clean from most interfering compounds and matrices that are suitable for multi-quantitative trace analysis. Such standardised methods, however, severely restrict the number of analytes for quantification and are not applicable when targeting new and emerging compounds as some may be less stable under acid treatment. Recently developed suspect and non-target screening analytical strategies (SUS and NTS, respectively) are shown to be effective evaluation tools aimed at identifying a high number of compounds of emerging concern. These strategies, combining highly sophisticated analytical technology with extensive data interpretation and statistics, are already widely accepted in environmental sciences for investigations of various environmental matrices, but their application to air samples is still very limited. In order to apply SUS and NTS for the identification of organic contaminants in air samples, an adapted and more wide-scope sample clean-up method is needed compared to the traditional method, which uses concentrated sulfuric acid. Analysis of raw air sample extracts without clean-up would generate extensive contamination of the analytical system, especially with PUF matrix-based compounds, and thus highly interfered mass spectra and detection limits which are unacceptable high for trace analysis in air samples. In this study, a novel wide-scope sample clean-up method for high-volume air samples has been developed and applied to real high-volume air samples, which facilitates simultaneous target, suspect and non-target analyses. The scope and efficiency of the method were quantitatively evaluated with organic compounds covering a wide range of polarities (logP 2–11), including legacy POPs, brominated flame retardants (BFRs), chlorinated pesticides and currently used pesticides (CUPs). In addition, data reduction and selection strategies for SUS and NTS were developed for comprehensive two-dimensional gas chromatography separation with low-resolution time-of-flight mass spectrometric detection (GC × GC-LRMS) data and applied to real high-volume air samples. Combination of the newly developed clean-up procedure and data treatment strategy enabled the prioritisation of over 600 compounds of interest in the particle phase (on GFF) and over 850 compounds in the gas phase (on PUF) out of over 25 000 chemical features detected in the raw dataset. Of these, 50 individual compounds were identified and confirmed with reference standards, 80 compounds were identified with a probable structure, and 774 compounds were assigned to various compound classes. In the dataset available here, 11 hitherto unknown halogenated compounds were detected. These unknown compounds were not yet listed in the available mass spectral libraries.

Urine analysis via a toilet-based device can enable continuous health monitoring, a transformation away from hospital-based care towards more proactive medicine. To enable reliable sample collection for a toilet-attached analyzer, here a novel sample collector is proposed. The applicability of the proposed sample collector is validated for long-term use. Geometric parameters of the 3D-printed sample collector are optimized. The collected and leftover volumes are quantified for a range of urination speeds and design parameters. For long-term cyclic use, the protein concentrations of samples are quantified and the effectiveness of washing the sample collector is assessed., NA

As a result of the activities carried out by people to maintain their daily lives in different places such as homes, hospitals, hotels or workplaces, waste consisting of furniture, paint, batteries, food waste, sachets, bottles, fabrics, and fibers with the heterogeneous structure is called Municipal Solid Waste (MSW). Secondary fuels with higher heating value, which are generated by recycling of non-recyclable and reusable wastes in municipal solid wastes, are called as Refuse Derived Fuel (RDF). In this study, Refuse Derived Fuel1 (RDF1 : taken in December, winter season) and Refuse Derived Fuel2 (RDF2 : taken in June, summer season) samples obtained from different dates were used. The ultimate, proximate, calorific value, X-Ray fluorescence (XRF), Thermogravimetric analysis (TGA), and Differential scanning calorimetry (DSC) analysis were performed for these samples. Combustion characterization from Refuse Derived Fuel samples was investigated in the applied analyzes. The results of the content analysis made were examined separately and compared with the Thermogravimetric analysis and Differential Thermal Analysis combustion graph curves. It was revealed that the Refuse Derived Fuel1 sample had a better combustion compared to the Refuse Derived Fuel2 sample, as the ash amount and content obtained as a result of the combustion also supported other data. In addition, the results of the analysis show how different the Refuse Derived Fuel samples taken from the same region in two different months are different from each other.

High-throughput sequencing (HTS) studies on invertebrates commonly use ethanol as the main sample fixative (upon collection) and preservative (for storage and curation). However, alternative agents exists, which should not be automatically neglected when studies are newly designed. This review provides an overview of the application of propylene glycol (PG) in DNA-based studies of invertebrates, thus to stimulate an evidence-based discussion. The use of PG in DNA-based studies of invertebrates is still limited (n = 79), but a steady increase has been visible since 2011. Most studies used PG as a fixative for passive trapping (73%) and performed Sanger sequencing (66%; e.g. DNA barcoding). More recently, HTS setups joined the field (11%). Terrestrial Coleoptera (30%) and Diptera (20%) were the most studied groups. Very often, information on the grade of PG used (75%) or storage conditions (duration, temperature) were lacking. This rendered direct comparisons of study results difficult, and highlight the need for further systematic studies on these subjects. When compared to absolute ethanol, PG can be more widely and cheaply acquired (e.g. as an antifreeze, 13% of studies). It also enables longer trapping intervals, being especially relevant at remote or hard-to-reach places. Shipping of PG-conserved samples is regarded as risk-free and is authorised, pinpointing its potential for larger trapping programs or citizen science projects. Its property to retain flexibility of morphological characters as well as to lead to a reduced shrinkage effect was especially appraised by integrative study designs. Finally, the so far limited application of PG in the context of HTS showed promising results for short read amplicon sequencing and reduced representation methods. Knowledge of the influence of PG fixation and storage for long(er) read HTS setups is currently unavailable. Given our review results and taking difficulties of direct methodological comparisons into account, future DNA-based studies of invertebrates should on a case-by-case basis critically scrutinise if the application of PG in their anticipated study design can be of benefit.

The objects of research were 5lactose-free and 5ordinary (lactose) yoghurts presented on the market in Kharkiv (Ukraine). When carrying out research work, a complex of generally accepted chemical, physicochemical, mathematical methods was used, corrected for the merchandising evaluation of yoghurts. The first stage of the study was to conduct a comparative organoleptic assessment of selected samples, paying attention to the uniformity of consistency, the presence of inclusions, the presence of foreign odors and flavors, as well as the uniformity of color. According to the results of a comparative organoleptic quality assessment, it was found that all the studied samples of yoghurts had the same pure, sour milk taste, without extraneous odors unusual for the product, with a well-expressed sour taste. The results of the consistency assessment indicate that on the surface of sample No.3 there was a separation of whey and a curd, with an undisturbed clot, which occurred due to the fact that lactose-free yoghurt was produced by the thermostatic method. The second stage of the comparative merchandising assessment of selected yoghurt samples was to determine their main physical and chemical parameters in accordance with the requirements of DSTU4343:2004 «Yoghurts. General technical requirements». The analysis of the physicochemical indicators of the studied samples showed that only sample 1 had deviations from the requirements of the normative and technical documentation, namely, the content of the mass fraction of dry substances was lower by 0.3%, which indicates non-compliance with the product manufacturing technology. The content of the mass fraction of dry substances of other samples was within acceptable limits. When determining the content of titratable and active acidity, the mass fraction of fat in yoghurts, it was found that all the samples under study did not deviate from the requirements of the regulatory and technical documentation. It was found that carrying out a commodity assessment (determination of organoleptic and physicochemical indicators) makes it possible to obtain a set of results on the freshness of the studied samples of lactose-free and ordinary (lactose) yoghurts.

Environmental DNA (eDNA) is increasingly popular as a useful non-invasive method to monitor and study biodiversity and community structure in freshwater and marine environments. To effectively extract eDNA from the filter surface is a fundamental factor determining the representativeness of the samples. We improved the eDNA extraction efficiency of an established Sterivex method by 12- to 16-fold using a larger volume of lysis buffer mix coupled with backflushing the cartridges. The DNeasy extraction column could be overloaded when the environmental sample input is high, possibly due to a higher nonspecific binding present in environmental samples, thus resulting in a relatively lower quantity measured. Therefore, we included an internal control DNA in the extraction to monitor the extraction and purification efficiencies in field samples, which is crucial for quantification of original eDNA concentration. The use of Takara Probe qPCR Mix supplemented with protein-based additives improved the robustness of the real time PCR assay on inhibitor-rich environmental samples, but prior purification by Qiagen PowerClean Pro Cleanup kit could be essential for inhibitor-rich water samples, even though the recovery rate was unexpectedly low (average 33.0%). The improved extraction and quantification complement the qualitative analyses including metabarcoding and metagenomics in field application.

This paper is aimed to analyse font and colour as non-verbal and paralingual components which have the capacity to influence and manipulate recipients of a message. On the basis of an extensive body of illustrative material, it has been established that by the use of colour variation, a single text fragment may be interpreted in several different ways, and may also be perceived differently by men and by women. It is demonstrated that colour and font characteristics are not exclusively graphic shells whose function is merely to record an oral statement in writing. They are semantically significant and multifunctional. It has been determined that font and colour are form-creating elements, which make possible the graphic reproduction of objects in everyday use, objects relating to reality and actuality. Variation in font and colour enable us to hypothesize that the mass media communication space is now characterized by a type of linguistic play utilizing these traits so as to render possible the projection of multiple-reading promotional texts. They also permit an economy in terms of space because of the fact that font techniques can perform formative and content functions simultaneously. Based on an experiment involving 60 participants, 30 of whom were male and 30 female, it was found that the information encoded in colour and font graphics shells is not difficult to perceive and to decipher. However, the survey found that women are more likely to perceive that information, although the difference in perception is not striking. When asked whether a sample of illustrative material stirred an appetite by using stylized fonts consisting of foods to convey a food-related message, 74 % of men and 37% of women in both articles answered in the positive, which in our study confirms the claim that food advertising promotes appetite arousal. The study also showed that most women who read the information perceive it holistically–their attention is not attracted solely by verbal and nonverbal components. On the other hand, only half of the men surveyed saw it as a whole, and almost a third of them initially noticed the verbal components first. Most participants in the experiment claimed that it took them from 5 to 10 seconds to realize that a single message could be read in several different ways. The participants who took part confirm that a single text string can be interpreted in multiple ways due to the font and colour attributes that are utilized in forming them.

Sweat sensors that can continuously sample sweat are critical for determining the time-dependent physiological responses occurring in normal daily life. Here, a new device, termed fluidic patch, for collecting human sweat samples at defined time intervals is developed, and the proof-of-concept is demonstrated. The device comprises micropumps and a disposable microfluidic patch attached to the human skin. The fluidic patch continuously collects aliquots of freshly secreted sweat accumulated in the fluidic pathway at accurately defined time windows (typically 5 min). By measuring the weight of the collected samples, the local sweat rate is calculated. The sweat sample collected can be directly subjected to a wide range of chemical analyses. For the proof-of-concept, we compared the sweat rates during passive heating in human trials using the fluidic patch and the conventional ventilated sweat capsule system. Although the sweat rate obtained using the fluidic patch highly correlated with that of the ventilated sweat capsule (R2 = 0.96, y = 1.4x - 0.05), the fluidic patch overestimated the sweat rate compared with the ventilated capsule system when the sweat rate exceeded 0.5 mg/(cm2·min). The sampled sweat was analyzed for sodium, potassium, chloride, lactate, pyruvate, and cortisol. The device could obtain the time courses of the concentrations of the abovementioned three ions; the concentrations of sodium and chloride increased linearly with the sweat rate during passive heating (R2 = 0.76 and 0.66, respectively). The device can reliably measure the sweat rate and collect sweat samples for chemical analysis. It can be utilized for real-time physiological investigations toward wider applications.

Sperm preparation is critical to achieving a successful intrauterine insemination and requires the processing of a semen sample to remove white blood cells, wash away seminal plasma, and reduce sample volume. We present an automated instrument capable of performing a sperm preparation starting with a diluted semen sample. We compare our device against a density gradient centrifugation by processing 0.5 mL portions of patient samples through each treatment. In 5 min of operating time, the instrument recovers an average of 86% of all sperm and 82% of progressively motile sperm from the original sample while removing white blood cells, replacing the seminal plasma, and reducing the volume of the sample to the clinically required level. In 25 min of operating time, density gradient centrifugation recovers an average of 33% of all sperm and 41% of progressively motile sperm. The automated instrument could improve access to IUI as a treatment option by allowing satellite doctor’s offices to offer intrauterine insemination as an option for patients without the clinical support required by existing methods.

The detailed chemical composition of crude oil in subsurface reservoirs provides important information about reservoir connectivity and can potentially play a very important role for the understanding of recovery processes. Relying on studying produced oil samples alone to understand the rock-fluid and fluid-fluid interactions is insufficient as the heavier polar components may be retained by tight reservoirs and not produced. These heavy and polar compounds that constitute the resin and asphaltene fractions of crude oil are typically present in low concentrations and yet are determining for the physical-chemical properties of the oil because of their polarity. In order to obtain a fingerprint analysis of oils including polar compounds from different wells, the oil content of drill cores has been extracted and analyzed. Infrared spectroscopy has been used to perform chemical fingerprinting of the oil extracted from drill cores sampled in different geographical locations of the Danish North Sea. Statistical analysis has been employed to identify the chemical differences within the sample set and explore the link between chemical composition and geographic location of the sample. A principal component analysis, based on spectral peak fitting in the 1800-1400 cm-1 range, has allowed for statistical grouping of the samples and identified the primary chemical feature characteristic of these groups. Statistically significant differences in the quantities of polar oxygen- and nitrogen-containing compounds were found between the oil wells. The results of this analysis have been used as guidelines and reference to establish an express statistical approach based on the full-range infrared spectra for a further expansion of the sample set. The chemical information presented in this work is discussed in relation to oil fingerprinting and geochemical analysis.

Nowadays great deal of research is physiological field is conducted on experimental animals and there is a lot of criticism from the wide public on methods used. Therefore, recently there is a lot of effort focused on the welfare of the animals. Main aim of this study is to determine the effect of experimental sample collection method on the selected parameters of stress. In the experiment two sample collections of rabbit blood from marginal ear vein were realized – first using standard method with one person fixing the animal and other collecting the blood using gently fixating the animal. In the second groups experimental method of inserting the experimental animal into a sack and further collection in dark was realized. During the experiment the levels of cortisol – main stress indicator in organism and other health parameters of animals including mineral profile and haematological parameters were observed. Our results show no significant changes in levels of cortisol but also a decreasing tendency in the sample from the second (dark) collection. Haematological parameters were generally in the reference values and any significant changes except levels of lymphocytes and percent of lymphocytes which shown significant increase in the second collection period were found. Also the levels of mean corpuscular haemoglobin and percent of neutrophils unveiled a significant decrease in values. Values of mineral profile parameters have indicated no significant changes except the levels of phosphorus. Based on the result we can state that the experimental sample collection has no effect on blood parameters of the animals but we spectated a statistically insignificant decrease in the levels of cortisol which can suggest that the dark collection is possibly less stressful to the animals.

A remote collection of biofluid specimens such as blood and urine remains a great challenge due to the requirement of continuous refrigeration. Without proper temperature regulation, the rapid degradation of analytical targets in the specimen may compromise the accuracy and reliability of the testing results. In this study, we develop porous superabsorbent polymer (PSAP) beads for fast and self-driven "microfiltration" of biofluid samples. This treatment effectively separates small analytical targets (e.g., glucose, catalase, and bacteriophage) and large undesired components (e.g., bacteria and blood cells) in the biofluids by capturing the former inside and excluding the latter outside the PSAP beads. We have successfully demonstrated that this treatment can reduce sample volume, self-aliquot the liquid sample, avoid microbial contamination, separate plasma from blood cells, stabilize target species inside the beads, and enable long-term storage at room temperature. Potential practical applications of this technology can provide an alternative sample collection and storage approach for medically underserved areas.

For graphene to achieve its full scientific and commercial potential, reliable mass production of the material on the multi‐tonne scale is essential. We have investigated five samples of graphene obtained from commercial sources that state they can supply the product on the tonne scale per annum. From electron microscopy at the micrometre to the nanometre scale, and neutron vibrational spectroscopy, we find that none of the materials examined were 100 % isolated graphene sheets. In all cases, there was a substantial content of graphite‐like material. The samples exhibited varying oxygen contents, this could be present as carboxylic acid (although other oxygenates, quinones, phenols may also be present) or water. We emphasise that INS spectroscopy is particularly useful for the investigation of inorganic materials that will be used commercially: it provides atomic scale information from macroscopic (10’s of g) amounts of sample, thus ensuring that the results are truly representative., Commercial graphenes from five different sources have been investigated. None of them are present as 100 % isolated sheets, rather they are present as stacks as shown by tilting experiments in the TEM: left, flat on the support, right, tilted 90°. Neutron vibrational spectroscopy of bulk quantities (10’s of g) shows that there are a variety of chemical functionalities and species present in the, nominally, graphene sheets.

There have been conducted probation studies of an improved uninterrupted pasteurization set “tube in tube” that allowed to provide modern market needs of consumers in getting high-quality food products that must undergo pasteurization stages at technological production. Heat delivery by FFREHRT is used in the set for providing heat flow distribution evenness. There has been established the optimal working space of processed raw materials by studying a temperature drop in the middle of the raw material flow and at the apparatus surface. At the width of the linear ring size of the working environment as 9.5mm and the flow speed as 0.4m/s there is provided the least temperature drop value as 0.7°С. At decreasing the air gap width, the temperature drop value increases and at 5.5mm is equal to 2°С that favors the effectiveness decrease of the pasteurization process. According to results of comparative indices of the main composition and obtained quality of pasteurized cow milk, just the experimental sample, obtained at the probation of the offered apparatus is advantageous, comparing with a traditional. It is explained by the decrease of milk temperature processing at the expanse of double pasteurization by FFREHRT, comparing with the traditional pasteurization method. The conducted studies prove the effectiveness of constructive-technological solutions for realization of pasteurization in the set “tube in tube”: the use of two-side heating by FFREHRT that due to its technical parameters is able to take any geometric form of the working chamber and at that provides the necessary evenness of heat flow distribution. We must also note the improvement of exploitation parameters of the offered set, namely facilitation of the automatic control of temperature regulation and the absence of the steam coat and correspondent armature as in the traditional apparatus that decreases metal consumption essentially. The obtained results are urgent for using the presented invention for pasteurization of different food raw materials (milk, juice, low-alcohol beverages and so on). The use of the improved pasteurizer allows to decrease resource consumption and to improve the quality of obtained products

All powered vehicles have a braking system adopted according to the type of vehicle and work for which they are designed. In Ecuador, there is a great variety of auto parts that are proposed as alternative replacement, varying in cost and quality. This research aims to quantitatively analyze the characteristics of the brake disc material between original and alternate auto parts. This research analyzes three brake disc samples (A, B, C) from different manufacturing sources, using the ASTM E415-08 spectrometry test and the metallography test under the ASTM A247-16A standard. The spectrometry detects 15 elements in each sample, the carbon equivalent of sample A is 18% and 20% higher in relation to sample B and C, which significantly influences the microstructure. The metallographic tests indicate a pearlitic matrix in each sample, however, there is a different distribution and size of the graphite flakes. According to the SAE J431 standard, each auto part meets the material conditions for the brake disc function., Todos los vehículos propulsados cuentan con un sistema de frenado adoptado según el tipo de vehículo y trabajo para el que están diseñados. En Ecuador existe una gran variedad de autopartes que se proponen como repuesto alternativo, que varían en costo y calidad. Este estudio tiene por objetivo analizar cuantitativamente las características del material de discos de freno entre autopartes originales y alternas. El estudio analiza tres muestras de disco de frenos (A, B, C), de diferente procedencia de fabricación, utilizando la prueba de espectrometría ASTM E415-08 y la prueba de metalografía, bajo la normativa ASTM A247-16A. La espectrometría detecta 15 elementos en cada muestra. El carbono equivalente de la muestra A es superior en un 18 % y 20 % en relación a la muestra B y C, lo cual influye significativamente en la microestructura. Los ensayos metalográficos, indican en cada muestra una matriz perlítica; sin embargo, existe una diferente distribución y tamaño de las hojuelas de grafito. Según la norma SAE J431, cada autoparte cumple con las condiciones de material para la función de disco de freno.

Motivation Single-cell RNA-sequencing has grown massively in scale since its inception, presenting substantial analytic and computational challenges. Even simple downstream analyses, such as dimensionality reduction and clustering, require days of runtime and hundreds of gigabytes of memory for today’s largest datasets. In addition, current methods often favor common cell types, and miss salient biological features captured by small cell populations. Results Here we present Hopper, a single-cell toolkit that both speeds up the analysis of single-cell datasets and highlights their transcriptional diversity by intelligent subsampling, or sketching. Hopper realizes the optimal polynomial-time approximation of the Hausdorff distance between the full and downsampled dataset, ensuring that each cell is well-represented by some cell in the sample. Unlike prior sketching methods, Hopper adds points iteratively and allows for additional sampling from regions of interest, enabling fast and targeted multi-resolution analyses. In a dataset of over 1.3 million mouse brain cells, Hopper detects a cluster of just 64 macrophages expressing inflammatory genes (0.004% of the full dataset) from a Hopper sketch containing just 5000 cells, and several other small but biologically interesting immune cell populations invisible to analysis of the full data. On an even larger dataset consisting of ∼2 million developing mouse organ cells, we show Hopper’s even representation of important cell types in small sketches, in contrast with prior sketching methods. We also introduce Treehopper, which uses spatial partitioning to speed up Hopper by orders of magnitude with minimal loss in performance. By condensing transcriptional information encoded in large datasets, Hopper and Treehopper grant the individual user with a laptop the analytic capabilities of a large consortium. Availability and implementation The code for Hopper is available at https://github.com/bendemeo/hopper. In addition, we have provided sketches of many of the largest single-cell datasets, available at http://hopper.csail.mit.edu.

With the advances of sequencing tools, the fields of environmental microbiology and soil ecology have been transformed. Today, the unculturable majority of soil microbes can be sequenced. Although these tools give us tremendous power and open many doors to answer important questions, we must understand how sample processing may impact our results and interpretations. Here, we test the impacts of four soil storage methods on downstream amplicon metabarcoding and qPCR analyses for fungi and bacteria. We further investigate the impact of thaw time on extracted DNA to determine a safe length of time during which this can occur with minimal impact on study results. Overall, we find that storage using standard cold packs with subsequent storage at −20°C is little different than immediate storage in liquid nitrogen, suggesting that the historical and current method is adequate. We further find evidence that storage at room temperature or with aid of RNAlater can lead to changes in community composition and in the case of RNAlater, lower gene copies. We therefore advise against these storage methods for metabarcoding analyses. Finally, we show that over 1 month, DNA extract thaw time does not impact diversity or qPCR metrics. We hope that this work will help researchers working with soil bacteria and fungi make informed decisions about soil storage and transport to ensure repeatability and accuracy of results and interpretations., Here, we test the impacts of four soil storage methods on downstream amplicon metabarcoding and qPCR analyses for fungi and bacteria and the impact of thaw time on extracted DNA to determine a safe length of time during which this can occur with minimal impact on study results. Overall, we find that storage using standard cold packs with subsequent storage at −20°C is little different than immediate storage in liquid nitrogen, suggesting that the historical and current method is adequate. We also show that over 1 month, DNA extract thaw time does not impact diversity or qPCR metrics.

Macroscopic materials are heterogeneous, multi-elementary, and complex. No material is homogeneous or isotropic at a certain small scale. Parts of the material that differ from one another can be termed “natural chips.” At different spots on the material, the composition, structure, and properties vary slightly, and the combination of these slight differences establishes the overall material performance. This article presents a state-of-the-art review of research and applications of high-throughput statistical spatial-mapping characterization technology based on the intrinsic heterogeneity within materials. High-throughput statistical spatial-mapping uses a series of rapid characterization techniques for analysis from the macroscopic to the microscopic scale. Datasets of composition, structure, and properties at each location are obtained rapidly for practical sample sizes. Accurate positional coordinate information and references to a point-to-point correspondence are used to set up a database that contains spatial-mapping lattices. Based on material research and development design requirements, dataset spatial-mapping within required target intervals is selected from the database. Statistical analysis can be used to select a suitable design that better meets the targeted requirements. After repeated verification, genetic units that reflect the material properties are determined. By optimizing process parameters, the assembly of these genetic unit(s) is verified at the mesoscale, and quantitative correlations are established between the microscale, mesoscale, macroscale, practical sample, across-the-scale span composition, structure, and properties. The high-throughput statistical spatial-mapping characterization technology has been applied to numerous material systems, such as steels, superalloys, galvanization, and ferrosilicon alloys. This approach has guided the composition and the process optimization of various materials.