Development Of Test Methods Research Articles

Development of a method for the impact performance characterization of commonly worn helmets in rodeo bull-riding

As the rodeo sport of bull-riding increases in popularity, dangers to bull-rider athlete safety continue to pose serious health risks. Despite frequent occurrences of head trauma in the sport, current test methods for evaluating helmets commonly worn in bull-riding fail to consider rotational head acceleration, which is correlated to concussive events in impact sports. Additionally, the second most prevalent mechanism contributing to head trauma in bull-riding is bull kick impacts, which have yet to be accurately modeled in a test method. Researchers aim to enhance bull-rider athlete protection through the development of a helmet test method that simulates bull kicks with a pneumatic linear impactor. The proposed test method considers impacts at two impact velocities and six impact locations using a flat and Equestrian Hazard Anvil. Two commonly worn helmets in bull-riding are evaluated in this study, and an adequate sample size is determined from analyzing variation between repeated impacts. The proposed test method is statistically validated, and researchers show that impacts at higher kicking velocities and impacts with the flat anvil result in increased rotational head accelerations. Ultimately, this study emphasizes the need for helmets designed specifically for the unique impacts of bull-riding by simulating bull kicks through pneumatic linear impactor testing to reduce rotational head kinematics and hoof penetration.

Review of the Hazards and Contraindications of Etomidate.

Etomidate, an ultrashort-acting non-barbiturate sedative derived from imidazole, exerts potent inhibitory effects on the central nervous system. It is commonly employed for the induction of intravenous general anaesthesia or assisted anaesthesia. Recently, etomidate has emerged as an alternative to narcotics and novel psychoactive substances, leading to an increasing trend of abuse. Chronic overdose of etomidate can result in irreversible brain damage and various mental disorders. Severe cases may manifest as mental disturbances, behavioural disorders, self-mutilation and even death. The toxicological mechanisms of etomidate remain poorly understood. Additionally, there is limited information on the clinical symptoms and histopathological changes associated with etomidate poisoning and standardized detection methods for etomidate in blood, urine and hair are lacking. Consequently, further research on toxicological pathology and the development of reliable testing methods is crucial. This study reviews the metabolism, distribution, adverse reactions, poisoning manifestations, toxicology mechanisms and testing methods of etomidate.

Application of Artificial Intelligence Technology for Prompt Diagnosis of Cast Iron Mechanical Properties

Kinetic indentation is widely used to measure physical and mechanical properties of materials as one of the most universal methods for non-destructive testing. This paper uses the latest advances in artificial intelligence and capabilities of the Python programming language libraries allowing to carry out accurate measurements of cast iron hardness based on the data of the material’s micro-impact loading diagram. It has been shown that use of machine learning allows eliminating gross errors and reducing the error of indirect hardness evaluation in several times – down to 10 units according to Brinell HB. It has also been established that formation of additional features for training models (based on traditionally used characteristics: penetration depths, indenter movement speed and contact forces at certain points in time) has a positive effect on the accuracy of measurements, but amount of measurements should also be optimized. Feasibility of effective use of machine learning to evaluate hardness has been demonstrated by comparing of calculated hardness values with data obtained with standard testing methods. Advantage of the developed testing method is the fact that the developed algorithms can be used for prompt diagnostics of cast iron hardness using existing equipment. It is appropriate to extend the proposed approach for determination of other mechanical properties of cast iron: yield strength, strain hardening index, creep, relaxation, determined by indentation methods.

Development and Application of a TaqMan RT-qPCR for the Detection of Foot-and-Mouth Disease Virus in Pigs

The global livestock industry is facing a serious threat from a widespread foot-and-mouth disease virus (FMDV) epidemic. The timely detection of FMDV can significantly mitigate its harmful effects. This study aimed to establish and evaluate a TaqMan fluorescence quantitative PCR assay to assess its sensitivity, specificity, reproducibility, and stability. The standard curve equation range is 6.43 × 109–6.43 × 101 copies/µL, with an R2 value of 0.996 and a standard curve equation of y = −3.586x + 36.245. The method successfully detected 64.3 copies/µL of the target gene for FMDV and exhibited high specificity for FMDV. Repeatability tests demonstrated low coefficients of variation within and between groups (<2%), indicating good reproducibility. The clinical samples analyzed using this method showed results consistent with those of the SYBR Green I RT-qPCR assay, confirming the reliability of the method. Overall, the developed test method displayed high sensitivity, specificity, reproducibility, and stability, making it suitable for the rapid diagnosis of foot-and-mouth disease in clinical settings.

Correction: Jones et al. The Development of a Novel Thin Film Test Method to Evaluate the Rain Erosion Resistance of Polyaspartate-Based Leading Edge Protection Coatings. Coatings 2023, 13, 1849

In the original publication [...]

Anaphylaxis and prolonged allergic reactions caused by intra-articular injection of diclofenac etalhyaluronate in knee osteoarthritis: A case report.

Osteoarthritis (OA) is a common condition. The treatment of knee OA aims to improve the quality of life and clinical symptoms, mainly knee pain. To develop a new treatment option, diclofenac etalhyaluronate (DF-HA;ONO-5704/SI-613; trade name: JOYCLU) was developed. Its anti-inflammatory and pain-relieving effects have been demonstrated. Conversely, adverse events have also been reported. Here, we report the case of a 71-year-old female who presented with anaphylaxis and prolonged allergic reactions after an intra-articular injection of JOYCLU. A basophil activation test (BAT) was performed to determine the cause of the anaphylaxis. BAT showed no positive findings. As the incidence of knee OA increases, the number of cases of JOYCLU use is expected to grow; therefore, careful administration is required. In this case, the cause was unknown by BAT. Thus, further development of appropriate testing methods is necessary. Intra-articular allergic reactions in knee OA may be modified and worsened besides normal allergic reactions; therefore, caution is required.

Development of the small punch fatigue test method based on the finite element method

The Small Punch Test (SPT) is a method of evaluating the mechanical properties of metallic materials that overcomes the limitations of the Uniaxial Test (UT), a traditional method of testing. Unlike UT, which provides strain data for each stress, SPT provides displacement data for each load. Therefore, SPT must be converted to UT to evaluate the mechanical properties of materials. However, SPT and UT employ disparate loading mechanisms. The difficulty in converting SPT to UT, which stems from the disparate loading mechanisms, has thus far limited SPT to mechanical property evaluation areas such as tensile and creep. This paper, therefore, aims to extend SPT to the fatigue domain, which is currently limited to the tensile and creep domains. The fatigue properties of metallic materials were evaluated based on the Finite Element Method (FEM) for the Small Punch Fatigue Test (SPFT). Moreover, the fatigue properties derived from the FEM for SPFT were converted to Uniaxial Fatigue Test (UFT) by employing the equivalent equation. Finally, an S-N curve was constructed based on SPFT and was validated by comparison with the same curve constructed based on UFT.

Testing Time Optimization Method for IEEE 802.15.4z Ultra-wideband Integrated Circuits

IEEE 802.15.4z-compliant ultra-wideband (UWB) devices are becoming ever more popular in contemporary radio engineering systems. Such systems are capable of precisely measuring distances (with their accuracy expressed in centimeters), are immune to interference, offer low latency and transmit data in an energy-efficient manner. Widespread adoption of UWB technology has triggered significant demand for testing integrated circuits these systems rely on, prompting the development of new testing methods to meet the ever increasing requirements in terms of testing speed and reliability. The same applies to sensitivity tests, in the course of which up to 2000 different packets may be received. The process of generating and analyzing such a large number of packets is time consuming. Furthermore, if multiple devices need to be tested simultaneously, the duration of the test will be multiplied accordingly. In such a context, the article investigates the lead time required to generate 2000 UWB packets using conventional methods and proposes a novel approach to significantly reduce packet generation time and improve testing efficiency.

Hygienic assessment of the protective properties of personal hand protection equipment during vibration testing

Introduction. In industrial environments, at the workplaces of hand tool operators, it is not always possible to completely eliminate increased levels of vibration exposure. The power and speed characteristics of modern hand-held machines are constantly increasing. The impact of local vibration on a person has a negative effect on his body. When working with hand tools, personal protective equipment is used. The purpose of personal hand protection against vibration is to reduce the vibration impact on a person. Materials and methods. Bench tests were carried out on hand protection products consisting of damping materials of various shapes and locations in the product. The vibration sensor was installed and fastened in places where the operator’s hands came into contact with vibration and on the forearm. The effectiveness of protection was determined by the difference in measurement levels. Results. During the tests, vibration levels were recorded on the handle of the vibration stand, the palmar surface, the fingers, and the operator’s forearm. In the low-frequency region of the spectrum, vibration attenuation is minimal, and as the frequency range increases, the attenuation increases. Across all areas of the spectrum, performance levels for mittens are higher than for gloves. In places where the fingers come into contact with vibration, the efficiency is less than when in contact with the hand, and in the low-frequency region of the spectrum a negative efficiency of up to 0.8 dB is noted. Vibration measurements on the operator’s forearm showed vibration levels in the forearm to be lower than in the hand. Limitations. The study was conducted over a period of one year, in laboratory conditions, and was limited to two thousand measurements. Conclusion. Hygienic assessment of the effectiveness of the protective properties of personal protective equipment for hands was carried out in accordance with developed laboratory test methods when installing and securing a vibration sensor on the handle, hand, and forearm of the operator. Determining the effectiveness of the entire product model should be considered when designing and manufacturing new hand protection against vibration.

Development of Test Methods in the Process of Electrically Conductive Concrete Production

Abstract Prevention of climate change, implementation of sustainable development principles in building industry, creation of Green buildings, Three-zero buildings (zero energy, zero emissions, zero waste), energy independent buildings maybe on the base of Smart Concrete. Electrically Conductive Concrete as type of Smart Concrete have the possibilities to create multifunctional hybrid structures for various purposes. The production of electrically conductive concrete is usually based on the introduction of carbon materials and carbon nanomaterials (CNMs) as electrically conductive fillers into its concrete composition. The theory of conductive percolation is used for design of electrically conductive concrete. To select electrically conductive carbon filler, it is necessary to summarize their electrically conductive characteristics. Today, there is no standard for determining the electrical conductivity of carbon fillers, nor is there a method for designing the composition of electrically conductive concrete; the development of both is imperative. Features of the preparation of electrically conductive concrete with hydrophobic carbon nanoparticles prone to aggregation are indicated. To obtain high quality electrically conductive products an operating system for quality control at the stages of the technological process of manufacturing must be proposed. Homogenization of the electrically conductive filler is very important. It is necessary to propose a method for assessing the stability of an aqueous suspension of a hydrophobic carbon material used for homogeneous distribution of a filler. Due to the lack of a standard, a method for determining the electrical conductivity of concrete is also needed.

Rearing conditions (isolated versus group rearing) affect rotenone-induced changes in the behavior of zebrafish (Danio rerio) embryos in the coiling assay

Under regulations such as REACH, testing of novel and established compounds for their (neuro)toxic potential is a legal requirement in many countries. These are largely based on animal-, cost-, and time-intensive in vivo models, not in line with the 3 Rs’ principle of animal experimentation. Thus, the development of alternative test methods has also received increasing attention in neurotoxicology. Such methods focus either on physiological alterations in brain development and neuronal pathways or on behavioral changes. An example of a behavioral developmental neurotoxicity (DNT) assay is the zebrafish (Danio rerio) embryo coiling assay, which quantifies effects of compounds on the development of spontaneous movement of zebrafish embryos. While the importance of embryo-to-embryo contact prior to hatching in response to environmental contaminants or natural threats has been documented for many other clutch-laying fish species, little is known about the relevance of intra-clutch contacts for zebrafish. Here, the model neurotoxin rotenone was used to assess the effect of grouped versus separate rearing of the embryos on the expression of the coiling behavior. Some group-reared embryos reacted with hyperactivity to the exposure, to an extent that could not be recorded effectively with the utilized software. Separately reared embryos showed reduced activity, compared with group-reared individuals when assessing. However, even the control group embryos of the separately reared cohort showed reduced activity, compared with group-reared controls. Rotenone could thus be confirmed to induce neurotoxic effects in zebrafish embryos, yet modifying one parameter in an otherwise well-established neurotoxicity assay such as the coiling assay may lead to changes in behavior influenced by the proximity between individual embryos. This indicates a complex dependence of the outcome of behavior assays on a multitude of environmental parameters.

Reveal the capacity loss of lithium metal batteries through analytical techniques

AbstractHigh energy density and stable long cycle are the basic requirements for an ideal battery. At present, lithium (Li) metal anode is regarded as one of the most promising anode materials, but it still faces major problems in terms of capacity fading and safe and stable long‐term cycle. The reason for the continuous fading of Li anode capacity is mainly due to the loss of active Li source, and the loss of Li source is mainly due to the continuous generation of dead Li. At the same time, the unstable interface and dendrite growth of Li anodes during the Li plating/delithiation process eventually lead to battery safety issues. In fact, recent studies have shown that the disordered expansion of dendrites is the main reason for the infinite generation of dead Li. Therefore, here we take different detection techniques as clues, review the exploration process of qualitative and quantitative research on the source and mechanism of Li capacity loss, and summarize the strategies to reduce dead Li generation and capacity fading by inhibiting dendrite formation. In particular, we give suggestions on the development of advanced testing methods on how to further study the problem of dead Li, and also give relevant strategy suggestions on how to completely solve the problem of capacity loss in the future, with the main goal of suppressing dendrites.

Authenticity Identification of F1 Hybrid Offspring and Analysis of Genetic Diversity in Pineapple

Breeding is an effective method for the varietal development of pineapple. However, due to open pollination, it is necessary to conduct authentic identification of the hybrid offspring. In this study, we identified the authenticity of offspring and analyzed the genetic diversity within the offspring F1 hybrids resulting from crosses between ‘Josapine’ and ‘MD2’ by single nucleotide polymorphism (SNP) markers. From the resequencing data, 26 homozygous loci that differentiate between the parents have been identified. Then, genotyping was performed on both the parents and 36 offspring to select SNP markers that are suitable for authentic identification. The genotyping results revealed that 2 sets of SNP primers, namely SNP4010 and SNP22550, successfully identified 395 authentic hybrids out of 451 hybrid offspring. We randomly selected two true hybrids and four pseudohybrids for sequencing validation, and the results have shown that two true hybrids had double peaks with A/G, while pseudohybrids had single peaks with base A or G. Further study showed that the identification based on SNP molecular markers remained consistent with the morphological identification results in the field, with a true hybridization rate of 87.58%. K-means clustering and UPGMA tree analysis revealed that the hybrid offspring could be categorized into two groups. Among them, 68.5% of offspring aggregated with MD2, while 31.95% were grouped with Josapine. The successful application of SNP marker to identify pineapple F1 hybrid populations provides a theoretical foundation and practical reference for the future development of rapid SNP marker-based methods for pineapple hybrid authenticity and purity testing.

Addressing chemically-induced obesogenic metabolic disruption: selection of chemicals for in vitro human PPARα, PPARγ transactivation, and adipogenesis test methods.

Whilst western diet and sedentary lifestyles heavily contribute to the global obesity epidemic, it is likely that chemical exposure may also contribute. A substantial body of literature implicates a variety of suspected environmental chemicals in metabolic disruption and obesogenic mechanisms. Chemically induced obesogenic metabolic disruption is not yet considered in regulatory testing paradigms or regulations, but this is an internationally recognised human health regulatory development need. An early step in the development of relevant regulatory test methods is to derive appropriate minimum chemical selection lists for the target endpoint and its key mechanisms, such that the test method can be suitably optimised and validated. Independently collated and reviewed reference and proficiency chemicals relevant for the regulatory chemical universe that they are intended to serve, assist regulatory test method development and validation, particularly in relation to the OECD Test Guidelines Programme. To address obesogenic mechanisms and modes of action for chemical hazard assessment, key initiating mechanisms include molecular-level Peroxisome Proliferator-Activated Receptor (PPAR) α and γ agonism and the tissue/organ-level key event of perturbation of the adipogenesis process that may lead to excess white adipose tissue. Here we present a critical literature review, analysis and evaluation of chemicals suitable for the development, optimisation and validation of human PPARα and PPARγ agonism and human white adipose tissue adipogenesis test methods. The chemical lists have been derived with consideration of essential criteria needed for understanding the strengths and limitations of the test methods. With a weight of evidence approach, this has been combined with practical and applied aspects required for the integration and combination of relevant candidate test methods into test batteries, as part of an Integrated Approach to Testing and Assessment for metabolic disruption. The proposed proficiency and reference chemical list includes a long list of negatives and positives (20 chemicals for PPARα, 21 for PPARγ, and 11 for adipogenesis) from which a (pre-)validation proficiency chemicals list has been derived.

Investigation on the biaxial tensile testing method for metal foil using cruciform specimen

The assessment of mechanical properties of metal foil under complicated stress states poses a considerable challenge, requiring the development of new testing methods and the optimization of new specimen geometry. In this research, the biaxial tensile method and specimen shape were designed and optimized by using simulation and experiment. It is determined that the strain measurement area can be suggested as the central area of 0.6 to 0.8 times the arm width. The influence of different parameters on the tensile results of cruciform specimens was comprehensively evaluated by finite element method and multi-factor analysis. The results indicate that the number of slits markedly impacts the stress–strain uniformity and shear stress in the central region, followed by the slit length. The effect of the arm width and the slit width is comparable, more influential than the corner radius. According to the analyzed results and application requirements, a four-axis independently driven biaxial tensile test machine for small scale samples was fabricated. During the biaxial tension, the center point offset of the specimen remains within ±0.01 mm. The displacement and load synchronization errors do not exceed 0.01 mm and 50 N, respectively, facilitating the precise control of four-axis synchronization. Conclusively, cruciform specimens featuring diverse geometric characteristics were designed for industrial pure titanium, 304 stainless steel, and Inconel 718 superalloy with thickness of less than 0.3 mm. The biaxial tensile tests were performed to delineate the yield loci, revealing notable anisotropy and size effect. The validation confirms the suitability of the testing method and optimized cruciform specimens for conducting biaxial tensile mechanical properties testing on metal foils characterized by diverse types and thicknesses.

Исследование сигнала внешнего магнитного поля асинхронного электродвигателя в режиме выбега

Currently, one of the important scientific tasks is the development and improvement of methods for non-destructive testing of asynchronous electric motors during operation. One of the promising areas of diagnostics is the use of an external magnetic field signal. However, its study in the run-down mode is not given due attention by the authors of scientific publications, despite a number of advantages of this signal. Therefore, the aim of this research is to confirm the possibility to record and study the signal of the radial component of the induction of the external magnetic field in the run-down mode of an asynchronous motor. So, the aim is relevant. The research is carried out using several test benches, real low-voltage and high-voltage asynchronous motors and a simulation model of an asynchronous electric motor designed in the Ansys software package. To process the signals, namely, to construct the frequency-time spectra of the external magnetic field in the run-down mode, the authors have used a program based on the Short Time Fourier Transform using the Flat-top window as a window function to more accurately determine the amplitudes of the harmonic components. During the research conducted on test benches, it has been found that the external magnetic field of the motor in the run-down mode will exist due to the phenomenon of residual magnetization. The possibility of modeling asynchronous motors considering residual magnetization has been proven and the reliability of the resulting model has been confirmed. The spectra of external magnetic field signals on real motors and simulation models in the run-down mode are presented. The external magnetic field signal in the run-down mode can be recorded both on simulation models and on real low-voltage and high-voltage asynchronous electric motors. During further research, it is planned to analyze the possibility of identifying faults in asynchronous motors using this signal.

Numerical and physical implementation of controlled stress wave excitation and waveform effect in SHPB system

The occurrence of stress waves with complex waveforms serves as a critical inducing factor and energy transmission carrier in various underground dynamic disasters. Therefore, the development of testing methods and equipment that excites complex stress waveforms, and application in laboratory and field tests, are crucial in advancing our understanding of rock dynamics. In this study, a split Hopkinson pressure bar (SHPB) impact testing system has been used as excitation equipment for complex stress waves and an effective excitation scheme to generate an arbitrary waveform is established. Large random data sets of striker outlines and the corresponding waveform data sets are generated using an efficient discrete bead-string model. In addition, a BPNN-RNN scheme is designed to train the inversion model from waveform set to striker outline set. The results of numerical and laboratory impact tests have shown that the training algorithm delivered excellent inversion accuracy for complex stress waveforms, and the turn-milled striker bars based on the inversion results excited the requisite waveforms in the SHPB system. Stress waves with equal energy and different waveforms result in significantly different impact failure patterns in sandstone samples.

A study of inter-fiber cohesion with quantitative measurement approach for staple fibers

Several qualities influence the processability of textile staple fibers: inter-fiber cohesion being one of the most important properties. Although various methods to measure this property have been explored, there is no consensus on the optimal technique, and existing methods often require specialized machinery. This article introduces and evaluates a straightforward method that utilizes only a carding machine and a tensile tester, both standard equipment in yarn laboratories. The proposed cohesion test method involves preparing carded webs, cutting them into nine rectangles, and then subjecting these samples to tensile testing. The method was initially assessed for repeatability and the normalization of results. Further experiments varied the fiber material (cotton and polyester), fiber organization, direction of fiber hooks, and finishing treatments. Force curves and their gradients were analyzed, alongside video footage, to study inter-fiber interactions during testing. The results demonstrated that the new test method could differentiate between fiber materials, fiber organizations, and quantify the effects from finishing treatments. The cohesion force (CF) of CO fibers was 30 % of that of PES fibers; carding had a greater impact on CO fibers compared to PES fibers, and treatment with lubricant reduced the CF by up to 35 %. However, the weight and dimensions of the samples must be controlled to ensure repeatability. In conclusion, the developed inter-fiber cohesion test method offers a promising and accessible approach to analyzing inter-fiber interactions in staple fibers.

Sedimentation field-flow fractionation for rapid phenotypic antimicrobial susceptibility testing: a pilot study.

The increase in antibiotic resistance is a major public health issue. The development of rapid antimicrobial susceptibility testing (AST) methods is becoming a priority to ensure early and appropriate antibiotic therapy. To evaluate sedimentation field-flow fractionation (SdFFF) as a method for performing AST in less than 3 h. SdFFF is based on the detection of early biophysical changes in bacteria, using a chromatographic-type technology. One hundred clinical Escherichia coli strains were studied. A calibrated bacterial suspension was incubated for 2 h at 37°C in the absence (untreated) or presence (treated) of five antibiotics used at EUCAST breakpoint concentrations. Bacterial suspensions were then injected into the SdFFF machine. For each E. coli isolate, retention times and elution profiles of antibiotic-treated bacteria were compared with retention times and elution profiles of untreated bacteria. Algorithms comparing retention times and elution profiles were used to determine if the strain was susceptible or resistant. Performance evaluation was done according to CLSI and the ISO standard 20776-2:2021 with broth microdilution used as the reference method. AST results from SdFFF were obtained in less than 3 h. SdFFF showed high categorical agreement (99.8%), sensitivity (99.5%) and specificity (100.0%) with broth microdilution. Results for each antimicrobial were also in agreement with the ISO 20776-2 recommendations, with sensitivity and specificity of ≥95.0%. This study showed that SdFFF can be used as a rapid, accurate and reliable phenotypic AST method with a turnaround time of less than 3 h.

Development of a non-animal testing method using genetically engineered biosensors for assessing skin sensitizers

Development of a non-animal testing method using genetically engineered biosensors for assessing skin sensitizers