Laboratory Applications Research Articles

Perspective of perovskite-based X-ray hybrid pixel array detectors

Compound semiconductors are playing a major role in the production of X-ray pixel detectors for the application in laboratories and beamlines at photon sources. The performance of these detectors has constantly been improved for the last decades but experiments are still limited by the properties of the detector material, especially under high flux illumination. The fast development of perovskite crystals opens the possibility for new materials to be used as highly efficient X-ray pixel detectors. The published data until now, of the transport properties, demonstrate the large potential of perovskite semiconductors. The achieved values are comparable with the ones of CdTe-based detectors. This paper presents potential perovskite-based detector materials and compares their performance with the state-of-the-art CdTe-based detectors. The perspectives of perovskite semiconductors are promising for the production of large area X-ray detectors but still some challenges remain.

Characterization of nuvita biosearch center (NBC) isolated lactic acid bacteria strains from human origin and determination of growth kinetic profiles of selected cultures under bioreactor

BackgorundIn recent years, there has been an increasing interest in the field of research into the isolation and characterization of probiotics in the prevention of diseases and the need to maintain the continuity of healthy microbiota. Therefore, the aim of this study is to isolate and identify bacteria found in maternal colostrum, breast milk, adult and infant feces, analyze possible probiotic potential, and reveal the developmental kinetics of selected strains.ResultsWe isolated 40 bacterial species from 4 different sources and identified 19 bacteria in the form of bacilli through molecular biology and carried out studies with 11 of them. Five of the selected strains showed the better results considering bile salt resistance and ability to survive at different pH and antimicrobial effect. When the adhesion capacity in cell culture is examined, the better 2 strains are; Lactobacillus pontis ZZ6780 and Lactobacillus reuteri NBC2680 were selected and the growth kinetics of these strains were demonstrated at the 3 L bioreactor scale. Finally, the growth kinetics of selected strains were determined and the maximum specific growth rate of selected Lactobacillus pontis ZZ6780 and Lactobacillus reuteri NBC2680 was calculated as 0.412 h− 1 and 0.481 h− 1, respectively. In addition, the dry cell matter amounts were found to be and 4.45 g/L and 5.23 g/L, respectively.ConclusionThis study established the groundwork for the selection of safety probiotics for the development and application of LAB. It is thought that the two strains obtained as a result of this study can be considered as potential probiotic strains in the food, pharmaceutical and cosmetic industries.

Characterization of maltose-binding protein-fused heparinases with enhanced thermostability by application of rigid and flexible linkers.

Heparinases, including heparinases I-III (HepI, HepII, and HepIII, respectively), are important tools for producing low-molecular-weight heparin, an improved anticoagulant. The poor thermostability of heparinases significantly hinders their industrial and laboratory applications. To improve the thermostability of heparinases, we applied a rigid linker (EAAAK)5 (R) and a flexible linker (GGGGS)5 (F) to fuse maltose-binding protein (MBP) and HepI, HepII, and HepIII from Pedobacter heparinus, replacing the original linker from the plasmid pMAL-c2X. Compared with their parental fusion protein, MBP-fused HepIs, HepIIs, and HepIIIs with linkers (EAAAK)5 or (GGGGS)5 all displayed enhanced thermostability (half-lives at 30°C: 242%-464%). MBP-fused HepIs and HepIIs exhibited higher specific activity (127%-324%), whereas MBP-fused HepIIIs displayed activity similar to that of their parental fusion protein. Kinetics analysis revealed that MBP-fused HepIIs showed a significantly decreased affinity toward heparin with increased Km values (397%-480%) after the linker replacement, whereas the substrate affinity did not change significantly for MBP-fused HepIs and HepIIIs. Furthermore, it preliminarily appeared that the depolymerization mechanism of these fusion proteins may not change after linker replacement. These findings suggest the superior enzymatic properties of MBP-fused heparinases with suitable linker designs and their potential for the bioproduction of low-molecular-weight heparin.

An MeV Proton Irradiation Facility: DICE.

Materials applied in nuclear environments such as fission or fusion power-plants face severe conditions. The irradiation by neutrons induces thermal loads and irradiation damage. Furthermore, coolants in contact with the materials induce corrosion, which is particularly challenging for liquid salts intended for the next generation of fission reactors. A new device (DICE) is installed at the 3.5 MV accelerator at DIFFER for the accelerated testing of such materials under combined irradiation and corrosion conditions. The DICE enables irradiation of samples at temperatures of up to 1050 K and in contact with liquid salts. An integrated shielding and a low power temperature control concept based on radiation cooling enables high-duty cycle application in a standard accelerator laboratory. Ion currents of up to 30 µA are possible with continuous irradiation. This work outlines the technical concept of the device and presents the first data.

Review of the potential benefits and challenges of artificial intelligence in clinical laboratory

Over the past few years, medical artificial intelligence (AI) has been extensively utilized within the healthcare industry. However, the deployment of AI raises complicated social and ethical issues related to security, privacy, and human rights. While the use of artificial intelligence (AI) has the potential to improve healthcare outcomes and operational efficiency, this article gives a detailed assessment of current cutting-edge AI breakthroughs in clinical laboratories. It focuses on the potential benefits of AI and its application in clinical laboratory. The use of AI in clinical laboratory is rapidly growing, with the potential to alter patient care in the near future. Furthermore, it has the potential to democratize modern laboratory services, making them available to people all around the world.

Improving the triphenylphosphine/triphenylphosphine oxide (TPP/TPPO)‐based method for the absolute and accurate quantification by FTIR‐ATR of hydroperoxides in oils or lipid extracts

AbstractResearch on natural sources of polyunsaturated fatty acids (PUFAs) for both food and nutraceutical prospects has significantly grown in recent years. Some plant oils and lipid extracts contain carotenoids, xanthophylls, sterols, and/or phenolic compounds that can provoke a lipid hydroperoxides (LOOHs) overestimation when quantifying them using nonselective colorimetric assays. Herein, we have optimized a mid‐infrared method using Fourier‐transform infrared spectroscopy coupled with attenuated total reflectance (ATR) to quantify LOOHs in oils or lipid extracts. This method is based on the conversion of triphenylphosphine (TPP) to triphenylphosphine oxide (TPPO) in the presence of hydroperoxides, with a direct assessment of TPPO levels following the formation of an oil film on the ATR crystal's surface, allowing for a low detection limit of 0.5 mmol of LOOH kg−1. The concentration of oil and TPP, as well as the reaction time, were optimized. It was demonstrated that the presence of pigments, unsaponifiable compounds, phenolics, and/or PUFAs on oils, do not disrupt the analysis. Furthermore, the stoichiometry of the TPP/LOOH reaction was examined, confirming the reliability of the method in detecting various forms of hydroperoxides. An accelerated oxidation study was carried out and the hydroperoxide contents measured using TPP/TPPO were found to be comparable to those obtained using the ferric thiocyanate method. Our method offers a fast, simple, robust, and sensitive approach to accurately quantify hydroperoxides, regardless of the chemical composition of oil or lipid extracts.Practical Application: The hydroperoxide assay method outlined in this study allows for the rapid and straightforward detection of hydroperoxides in pure oil matrices. The method's elevated sensitivity facilitates the early identification of oxidation indicators in oils, especially those with significant carotenoid or xanthophyll contents since these compounds may affect the results when using methods based on colorimetric quantification of hydroperoxides. This accurate, precise, and reproducible approach requires only small quantities of test samples and chemical products, making it well suited to routine application in laboratories and industrial environments.

Performance evaluation of bio-oil and rubber compound modified asphalt mixture: Lower mixing temperature and carbon emission

Due to the high viscosity of high-content rubber modified asphalt, maintaining a high temperature for a long time is required when preparing rubber modified asphalt mixtures. This problem limits the attainment of ideal conditions in experimental research. Using the bio-oil could reduce the viscosity of rubber modified asphalt and thus reduced the mixing temperature of its mixtures. The objective of the manuscript is to propose production protocol of bio-oil rubber modified asphalt mixture (BRMAM) and evaluate its performance. The rubber (20 % mass ratio of modified asphalt) and bio-oil (5 % and 10 % mass ratio of modified asphalt) were used to prepare two types of the BRMAM under lower mixing temperature. The high-temperature stability, low-temperature anti-cracking, water stability and other mechanical performance were appraised. Based on the test results, the total deformation of the BRMAM decreased by 39.4 %, the Marshall modulus increased by 45.5 % compared to the neat asphalt mixture, and their fracture energy increased by 36.27 %. Under the condition of high stress ratio, the fatigue life of modified asphalt mixture rose by 32.4 %. The addition of crumb rubber could enhance the elastic recovery of BRMAM. The synergism of the bio-oil and crumb rubber could lower the mixing temperature without sacrificing the performance. This study provides a basis for BRMAM in the laboratory and field applications or similar scenarios. The study could contribute to the recycling of renewable resources and the reduction of carbon emission.

Assessing the setting behavior of ultra-high performance concrete

The setting behavior of ultra-high performance concrete (UHPC) is demonstrably different from that of conventional concrete; thus, tools and guidance extending beyond common test methods such as Vicat and penetration are needed. While UHPC is known for its enhanced mechanical and durability properties, due to the low water and high cementitious contents, UHPC-class materials are prone to early-age autogenous shrinkage. Recognizing that UHPCs are commonly supplied to construction sites as prebagged, proprietary mixes with unknown constituents, and that accurate determination of setting time is crucial in determining the early-age autogenous shrinkage of UHPC-class materials as well as for scheduling construction operations and quality control actions, this study explores alternate test methods such as isothermal calorimetry (ASTM C1679), semi-adiabatic calorimetry (ASTM C1753), autogenous shrinkage (ASTM C1698), chemical shrinkage (ASTM C1608), and dual ring test (American Association of State Highway and Transportation Officials (AASHTO T 363) to evaluate the setting behavior of UHPCs. Setting times obtained using the alternate test methods aligned well with each other and were found to be different than the setting times indicated through standard test methods. Discussion and guidance on the applicability and the use of alternate test methods to determine the setting time of UHPCs for various laboratory and field applications are provided.

The Effect of STEM Education Practices on the Awareness towards STEM Education and Opinions of Preservice Science Teachers

This study aims to examine the effects of STEM education practices on preservice science teachers' (PSTs) awareness of STEM and STEM education and their views on the implementation process. The study was designed as a one-group pretest/posttest weak-experimental design including a case study. The participants were 30 PSTs enrolling in the Science Teaching Laboratory Applications I course in the 2018-2019 academic year and were determined by convenience sampling. In the study that lasted nine weeks, five STEM activities were practiced. STEM awareness open-ended questionnaire (STEM-A) was administered as pre and posttest, and the obtained data was evaluated with the thematic analysis. At the end of the instructional practices, semi-structured interviews were conducted with ten volunteer participants and the data were analyzed with the content analysis method. According to the findings, it can be stated that the participants' awareness developed positively and they grasped the importance of interdisciplinary relationship and integrated structure of the STEM approach.

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.

The Application of Virtual Simulation Laboratory in University Physics Teaching

The Application of Virtual Simulation Laboratory in University Physics Teaching

Application of Turbiscan Lab® to study the mechanism of fining in red wine using a specific yeast protein extract: A comparison with gelatine

Fining of wines using proteins is a standard practice in the winemaking process. Gelatine is a common fining agent used for red wines. However, the consumer demand for wines that are free of animal-derived products has reinforced the search for alternative protein sources such as yeast origin as the latter is originally present in wine. In 2012, the International Organization of Vine and Wine (OIV) authorized yeast protein extract (YPE) as a processing aid for the fining of musts and wines (OIV-Eno 452–2012). The present work aimed at better understanding the fining mechanisms of a specific YPE, to evaluate the part played by interactions in solution with polyphenols, but also at the interfaces with suspended particles. Polyphenols from the soluble phase of red wine were separated from the suspended particles by centrifugation, and these particles were resuspended in a wine model solution. Interactions with YPE were studied with each fraction separately through static multiple light scattering (SMLS) using the Turbiscan Lab® apparatus and optical microscopy. The impact on wine color and astringency was assessed by UV–visible spectrophotometry and BSA assay test. Faster aggregation and sedimentation kinetics were observed with gelatine than with YPE, but the levels of clarification and lees were similar for both fining agents after a couple of hours (4 h maximum). Gelatine resulted in higher tannin and pigment removal, likely to decrease astringency but also derived pigments involved in red wine color stability. Meanwhile, the impact of the YPE was moderate, likely to modulate astringency while preserving wine color and structure. In addition to interacting directly with polyphenols in solutions such as gelatine, YPE exhibited the additional ability to trap particles and promote their sedimentation in the absence of tannins. This double performance of the YPE used in this work, is likely to guarantee an effective fining of red wines as well as for low tannin content matrices such as rosé and white wines.

Bacteriophage Removal from Infected Salmonella Cultures.

Bacteriophages, or simply phages, play a vital role in microbial environments, impacting bacterial populations and shaping their evolution and interactions. These organisms are viruses that infect and replicate within bacterial hosts. Phages are ubiquitous on Earth, highly diverse, and very abundant. While bacteriophages have valuable roles in different environments and are a key area of research in microbiology and ecology, their presence can be undesirable in certain industrial processes or products. Considering the abundance and ubiquity of bacteriophages on Earth, the design of procedures for the removal of bacteriophages from bacterial cultures is crucial in diverse laboratory and industrial applications to preserve the integrity of the cultures and ensure accurate experimental results or product quality. Here, we have fine-tuned a protocol to eliminate the bacteriophages from infected Salmonella enterica cultures, using a strategy based on the use of lipopolysaccharides (LPS) located in the outer membrane of Gram-negative bacteria. Bacterial LPS plays an important role in host recognition by phages, and we make use of this property to design an effective procedure for the removal of phages, which use LPS as a receptor, in Salmonella bacterial cultures.

The Impact of the Covid-19 Pandemic Process on Classroom Teacher Candidates' Self-Efficacy Beliefs in the Science Laboratory Applications Course

Face-to-face instruction was discontinued due to the Covid-19 pandemic, and problems emerged with the implementation of the three-semester online and two-semester hybrid educational models, particularly in the courses that required laboratory studies. The science laboratory applications course, which the students of the classroom teaching program are responsible for, was one of the courses in which these difficulties were encountered. Within the scope of this course, pre-service teachers must conduct one-on-one experiments and present them to their peers. In this study, which attempted to determine the impacts of the practices that were not conducted during the pandemic process on the self-efficacy beliefs of teacher candidates for this course, first of all, the "Self-Efficacy Scale for the use of science laboratory" developed by Kızkapan and Saylan-Kırmizigul (2021) was used. The candidates' views regarding the various methods of conducting this course were then taken in writing. The analysis revealed that the candidates who took the course online and, in a hybrid learning environment had lower self-efficacy beliefs than the candidates who took the course face-to-face. Also, it was found that almost all of the pre-service teachers preferred to take the course face to face.

A Novel Multi-epitope Vaccine Based on Virulence Stimulating Two-component Protein EsrA Against Fish Pathogenic Edwardsiella tarda – An Immunoinformatic Approach

Edwardsiellosis, caused by the gram-negative pathogen Edwardsiella tarda, is a major global aquaculture threat. Despite vaccination being a potential strategy, development of effective vaccines remains a challenge. The study aimed to develop a multi-epitope vaccine (EsrAmev) against virulent EsrA antigen in fish pathogenic E. tarda using an immunoinformatic approach. The study identified antigenic, non-allergenic, and nontoxic epitopes for cytotoxic T lymphocytes, helper T-lymphocytes, and linear Blymphocytes. They were combined to create the EsrAmev construct, with TLR4 agonist added for the immunogenicity. The physiochemical analysis of EsrAmev by ProtParam server showed a molecular weight of 29 kDa, an antigenicity score of 0.5966, and a solubility of 0.823563 with immunogenic, non-allergenic and non-toxic properties. Robetta, Mod, and Galaxy refiner servers refined the EsrAmev 3D structure, achieving 97.4% RAMA-favoured region, stable interactions, binding stability, and structural stiffness with TLR4 receptor. The EsrAmev construct, optimized for high immune responses in Escherichia coli K12 model, was successfully cloned into the pET28a (+) vector in silico for future wet lab applications. These findings suggests that the EsrAmev multi-epitope vaccine might have potential for the prophylaxis of E.tardacausing Fish Edwardsiellosis.

Bacteriocinogenic anti-listerial properties and safety assessment of Enterococcus faecium and Lactococcus garvieae strains isolated from Brazilian artisanal cheesemaking environment.

This study aimed to prospect and isolate lactic acid bacteria (LAB) from an artisanal cheese production environment, to assess their safety, and to explore their bacteriocinogenic potential against Listeria monocytogenes. Samples were collected from surfaces of an artisanal-cheese production facility and after rep-PCR and 16S rRNA sequencing analysis, selected strains were identified as to be belonging to Lactococcus garvieae (1 strain) and Enterococcus faecium (14 isolates, grouped into three clusters) associated with different environments (worktables, cheese mold, ripening wooden shelves). All of them presented bacteriocinogenic potential against L. monocytogenes ATCC 7644 and were confirmed as safe (γ-hemolytic, not presenting antibiotic resistance, no mucus degradation properties, and no proteolytic or gelatinase enzyme activity). Additionally, cell growth, acidification and bacteriocins production kinetics, bacteriocin stability in relation to different temperatures, pH, and chemicals were evaluated. According to performed PCR analysis all studied strains generated positive evidence for the presence of entA and entP genes (for production of enterocins A and enterocins P, respectively). However, pediocin PA-1 associated gene was recorded only in DNA obtained from E. faecium ST02JL and Lc. garvieae ST04JL. It is worth considering the application of these safe LAB or their bacteriocins in situ as an alternative means of controlling L. monocytogenes in cheese production environments, either alone or in combination with other antimicrobials.

Estimation of Effective Fracture Aperture in Glacial Tills by Analysis of Dye Tracer Penetration.

This study advances a methodology to estimate effective apertures of fractures in glacial tills based on dye tracer infiltration tests and numerical simulations. The approach uses the visible penetration depth of the dye tracer along fracture flow paths as primary information to calculate effective fracture apertures. Further data used in the calculation are the dye tracer input concentration and retardation, the duration of the tracer injection, and the hydraulic gradient applied to control the infiltrating water fluxes. The method does not require measurement of hydraulic conductivity for the fractured till and enables direct observation of flow and transport patterns within the fractures (e.g., uniform flow and dye tracer distribution, channeling due to aperture variability, and presence of biogenic macropores in fractures). The approach was successfully verified by using the estimated effective fracture aperture values in Large Undisturbed Columns (LUCs) to consistently simulate both the observed LUC effluent breakthrough of a conservative bromide tracer and the water fluxes with the hydraulic gradient applied in the experiments. Sensitivity analyses revealed that estimation of small effective fracture apertures (<10 μm) required accurate determination of the dye tracer retardation factor. By contrast, in the case of larger effective apertures (>20 μm), the sensitivity of the estimated effective fracture aperture to variations in the porous material and solute transport parameters was low compared to the dominant sensitivity to the water flow through the fractures (cubic relation between flow and aperture). The proposed approach may be extended beyond laboratory applications and assist in characterizing field-scale fracture networks.

A Review of Recent Improvements, Developments, Influential Parameters and Challenges in the Friction Stir Welding Process

Friction Stir Welding (FSW) is an innovative and reliable welding technique. Since this method is environmentally beneficial, it has received much attention and development over the past few decades. This study aims to revise the conceptual facts of FSW and evaluate the most recent improvements and developments in its applications. This review also assesses the influences of design parameters such as rotational and welding speeds on weld quality and joint efficiency. Existing challenges associated with applying FSW in various contexts, as well as the potential advantages that might lead to further study and broader FSW applications, are addressed. It has been concluded that FSW allows for optimising the rotating speed based on the preferred welding speed to achieve the greatest tensile strength in the welded materials. Despite FSW being established as effective in laboratory and small-scale applications, utilising FSW for large structures poses challenges. These challenges include maintaining consistent weld quality, controlling heat dissipation, and ensuring joint integrity during FSW. Consequently, further research is required to resolve these challenges and make FSW a promising welding method in contemporary production sectors.

A ratiometric fluorescent probe based on UiO-66-TCPP for selective and visual detection of quercetin in food

Quercetin (QCT) is a flavonoid with significant health benefits, necessitating sensitive detection methods for food safety and quality control. This study presents a novel UiO-66-TCPP ratiometric fluorescent probe for the quantitative and visual detection of QCT. Under optimal conditions, the fluorescence intensity of UiO-66-TCPP decreased linearly with increasing QCT concentration, with a detection limit of 26 nM. The probe demonstrated high specificity, showing no significant interference from various substances and QCT analogues. Practical applicability was confirmed by testing artificially contaminated juice samples, achieving recovery rates between 98.0% and 104.8%. Furthermore, a paper-based sensor was developed by incorporating UiO-66-TCPP onto Whatman#1 chromatography paper. This sensor exhibited stable fluorescence and a reliable, sensitive visual response to QCT concentrations, detectable via a smartphone-based color recognizer application. The UiO-66-TCPP ratiometric fluorescent probe provides a sensitive, specific, and practical method for detecting QCT in food matrices, offering significant potential for both laboratory and on-site applications.

Pes planus level affects counter movement jump performance: A study on amateur male and female volleyball players.

The aim of this study was to investigate the effect of pes planus level on counter movement jump (CMJ) performance parameters in amateur female and male volleyball players. In this context, amateur volleyball players aged between 18 and 23 years actively playing in the university school volleyball team were included in the study. Pes planus levels of the participants were analyzed using the navicular drop test (NDT). My Jump Lab application was used for CMJ measurement. Within the scope of CMJ, the participants' jump height, force, relative force, power, relative power, average speed, take-off speed, impulse, and flying time were analyzed. According to the linear regression results between NDT and CMJ parameters, force in males (t = 12.93, P = .049) and average speed in females (t = -3.52, P = .017) were significantly associated with NDT. NDT was similar in men and women (P > .05). However, all CMJ parameters were highly different between genders (P < .001). In the correlation analysis between sport age and physical characteristics and CMJ parameters; height (r = .386, P = .046), weight (r = .569, P = .002), leg length (r = .389, P = .045), foot length (r =. 558, P = .005), foot width (r = .478, P = .018), force (r = .407, P = .039), impulse (r = .460, P = .018) parameters, and sport age. The results suggest that the average speed in females and force in males both significantly influenced NDT, highlighting the significance of both factors in predicting NDT scores. Moreover, all CMJ measures showed significant variations between genders, although the NDT scores did not. Furthermore, the correlation analysis demonstrated a strong correlation between a number of physical attributes and CMJ parameters, highlighting the multifaceted nature of athletic performance and indicating the possible impact of these attributes on CMJ results.