Experimental Samples Research Articles

Performance of heat transfer in Al2O3/MWCNT hybrid nanofluid flow using machine learning models

Abstract This investigation diverges from traditional studies concentrating on single-component nanofluids, instead examining the thermophysical benefits of hybrid nanofluids, like Al₂O₃/MWCNT, aimed at improving thermal conductivity and heat transfer efficiency in passive systems. Machine learning is a promising solution for designing efficient heat exchangers by understanding intricate relationships and utilizing suitable modelling techniques. Numerical simulations were conducted to validate the benchmark results; later, passive techniques were incorporated into the numerical model to predict the heat transfer characteristics. The dataset derived from numerical simulation results is employed to train contemporary machine learning methodologies, including support vector regression (SVR), decision tree (DT), and random forest (RF). Data from experiments and CFD analysis were gathered for preprocessing and machine learning (ML) analysis. The preprocessing phase involved the application of a standard scaler operation to enhance accuracy levels. The models underwent validation using ten experimental data samples to assess their performance against statistical tool metrics. A higher thermal performance factor (ThPF) is observed with the divergent nozzle insert in the plain tube at 0.028 vol% of MWCNT/Al2O3 (HNF3) at Reynolds number 3093. R2 values of SVR, DT and RF are predicted as 0.95, 0.98 and 0.99, respectively, for the case of HNF3 fluid flowing through the divergent nozzle insert. The investigation broadens its conclusions to include improvements in passive heat transfer, encompassing extended surfaces and geometric alterations, offering practical guidance for developing advanced heat exchanger designs.

فاعليَّة برنامج تدريبيّ مقدَّم على منصَّة رقميَّة إلكترونيَة لتنمية مهارة التَّصميم التَّسويقي الرَّقميِّ لدى متدرِّبي المعهد الصِّناعيِّ الثَّانويِّ في جدَّة

This study aimed to investigate the effectiveness of a training program delivered on an electronic platform(coursera) to enhance digital marketing design skills among trainees at the Secondary Industrial In the city of Jeddah, in the Kingdom of Saudi Arabia. By applying action research on a purposefully selected experimental sample, the research sample included (20) second-year secondary school trainees from the computer science track at the Secondary Industrial Institute in Jeddah. A pre- and post-assessment test was developed specifically for the instructional design in this study. The research tool consisted of two main axes: the first axis focused on designing the digital marketing product, and the second axis on writing digital marketing content. The study results revealed statistically significant differences between the pre-test and post-test scores, favoring the post-test application across all skills represented by the scale. The study also recommended training small business owners affiliated with technical and vocational training and graduates of the Secondary Industrial Institute to develop digital marketing design skills in their marketing campaigns.

Modeling and thermal property of multi-layer warp knitted spacer fabrics

With its unique three-dimensional structure, high porosity, and lightweight, warp-knitted spacer fabric (WKSF) is an excellent insulation material. Multilayer fabric is an effective solution for better heat control, meeting the different requirements of a wide range of applications in the field of temperature control. To know the relationship between structural parameters and heat conductivity, this study highlighted the heat transfer mechanism of multilayer WKSFs. Experimental WKSF samples were fabricated in a double needle bar warp knitting machine and had mesh and plain side layers, different thicknesses of 3 mm, 4 mm, and 4.7 mm. These samples were grouped into multilayer systems by changing thickness and contacting modes between two samples. Experimental results show that the number of layers and the type of contact between the layers affects the internal thermal convection of the multilayer system and thus has a significant effect on its thermal resistance. Also, the WKSF thickness plays a role in the thermal resistance of the multilayer system. To further clarify the heat conducting behavior from a microscopic perspective, a geometry model of multilayer WKSFs and transfer of heat physical field was constructed to perform finite element simulation by ANSYS. By comparing the simulation results with the test results, the established simulation model was practical and it was found that the heat transfer paths of multilayer WKSFs were affected by the distribution of media with different thermal conductivities. The research provides a theoretical reference for studies on thermal insulation materials.

Stability comparison of prasugrel tablets unit‐dose packaged versus maintained in the manufacturer container over 90 days

AbstractBackgroundUnit‐dosing medications can improve time to drug administration and patient safety in inpatient settings. No available information supports the practice of unit‐dosing for prasugrel.AimThe stability of unit‐dosed prasugrel tablets was evaluated against tablets maintained in the manufacturer container.MethodThree lots of 10 mg prasugrel tablets were packaged as individual unit‐doses and stored at room temperature. Tablets were analysed for prasugrel concentration over a 90‐day period and compared against control tablets retained in the manufacturer's container. Prasugrel was quantified using a previously validated stability‐indicating high‐performance liquid chromatography method with ultraviolet detection. Experimental lots were monitored for >10% loss of potency. A non‐linear one‐phase decay curve was used to describe drug potency changes in experimental versus control tablets. Ethics approval was not required for this research article as it was a stability study and did not involve human subjects.ResultsAverage potency in all groups remained above 90% for the duration of the study; however, some individual experimental samples dropped below 90% at 7 days. Control tablets did not show a statistically significant potency change until 90 days. Modelling data indicated the ending average potencies in the experimental versus control tablets were 9.083 mg and 9.736 mg, respectively.ConclusionUnit‐dosing 10 mg prasugrel tablets has a negative effect on potency, which was most pronounced by day 7. The average potency remained above 9.00 mg over the 90‐day period. Conservative interpretation of these data may allow institutions to unit‐dose prasugrel tablets and discard after 72 h, when individual data points showed <90% potency. The decision to unit‐dose prasugrel must consider several factors surrounding patient care and individual institutional standards.

Glassy Dynamics and Local Crystalline Order in Two-Dimensional Amorphous Silica.

We reassess the modeling of amorphous silica bilayers as a 2D classical system whose particles interact with an effective pairwise potential. We show that it is possible to reparametrize the potential developed by Roy, Heyde, and Heuer to quantitatively match the structural details of the experimental samples. We then study the glassy dynamics of the reparametrized model at low temperatures. Using appropriate cage-relative correlation functions, which suppress the effect of Mermin-Wagner fluctuations, we highlight the presence of two well-defined Arrhenius regimes separated by a narrow crossover region, which we connect to the thermodynamic anomalies and changes in the local structure. We find that the bond-orientational order grows steadily below the crossover temperature and is associated with transient crystalline domains of nanometric size. These findings raise fundamental questions about the nature of the glass structure in two dimensions and provide guidelines to interpret the experimental data.

Dependency of mechanical properties in Ti-7Mo-3Al-3Cr-3Nb alloy on the β phase stability: Regulating primary α phase

In this study, the modification of the β-phase stability of Ti-7Mo-3Al-3Cr-3Nb alloy has been achieved by heat treatment at different temperatures. The synergy effects of primary α-phase and β-phase stability on the deformation behavior and mechanical properties were systematically studied based on these samples, combining the electron backscattering diffraction and transmission electron microscopy techniques. The content of the primary α-phase and stability of the β-phase increase when the heat treatment temperature is lowered from 860°C to 770°C, which increases the yield strength of the alloys. When the content of primary α-phase is less than 9%, high strength and ultra-high work-hardening rates can be simultaneously achieved, with maximum work-hardening reaching 12.75GPa and the ultimate tensile strengths reaching 846MPa. Stress-induced α′′ martensitic (SIM α′′) transformation is observed in all experimental samples during tensile deformation, and the trigger stress of martensitic transformation decreases with the decrease of β-phase stability. When the stability of the β-phase decreases, the quantity of SIM α′′ increases, while martensitic variants and twinned martensite increase to coordinate local strains. Meanwhile, as the strain increases, the martensite laths grow into martensite domains, which trigger martensite twins during deformation, and the interaction of the primary α-phase and β-phase deformation products will achieve different work-hardening rates. This study provides a possible strategy for the design and modification of new high-strength and 、work-hardening rate titanium alloys.

Biomimetic Effect of Saliva on Human Tooth Enamel: A Scanning Electron Microscopic Study.

Introduction: Due to the presence of ion reservoir, saliva may facilitate enamel remineralization and neutralize pH of acidic beverage leads to prevent enamel demineralization. Saliva substitute/artificial saliva has been developed in subsequent years and may differ in physical properties, function, or pH level from 5.0 to 7.3. Objectives: To evaluate the biomimetic effect of saliva (neutralization) on tooth enamel exposed to carbonated beverage (pH 2.44) and to observe therapeutic capability (remineralization) of artificial saliva over previously eroded (grade 3 and grade 5) enamel surface. Methods: After scanning with electron microscope (SEM-EDX), nondemineralized crown samples (n = 40) were randomly grouped into two. Samples (50%) were flushed all around to carbonated beverage with collected natural saliva bathing simultaneously (experimental group, n = 20), and the rest flushed to beverage only without saliva bathing simultaneously (control group, n = 20). Flushing action was performed for 3 min by a customized digital automatic flusher for 30 times for each sample. Samples (n = 40) were further scanned under SEM-EDX to evaluate the demineralization grade and concentration of Ca, P, O, and C elements of crown samples to find out the neutralization effect of saliva. In the second phase, already demineralized crown samples (n = 30) were randomly treated with artificial saliva having two different pH (7 or 6.8, experimental groups) and distilled water (control group) for 15 min 3 times daily for 30 days. The remineralization score of experimental samples was graded, and therapeutic capability was established. Results: Samples, when exposed to a carbonated beverage with saliva bathing simultaneously, showed low level of demineralization (mean 2.9 ± 0.3) than the control (without saliva) (mean 4.8 ± 0.3) (p = 0.01) which indicated neutralization (bioimimetic) effect of natural saliva. All (100%) of demineralized samples treated with both artificial saliva (pH 7 or pH 6.8) showed significant remineralization (p = 0.01), thus revealed biomimetic capacity. SEM-EDX analysis showed initial (before beverage exposure) concentrations of calcium, phosphorus, oxygen, and carbon elements of crown samples were 32.48%, 31.5%, 28.3%, and 5.5%, respectively. The calcium (Ca) (9.7%) and phosphorous (P) (18.5%) values were more decreased after beverage exposure without saliva bathing simultaneously compared to after beverage exposure with saliva bathing simultaneously. The concentration of oxygen (54.4%) and carbon (15.5%) were more increased after beverage exposure without saliva bathing simultaneously compared to after beverage exposure with saliva bathing simultaneously. Though the concentration of calcium (38.5%) of the crown sample was increased after treatment with artificial saliva (pH 7), but the phosphorus (18.5%) concentration of the crown sample was not increased. Conclusion: Within the context of the present study, both natural and artificial saliva showed significant biomimetic effects with respect to neutralization and remineralization.

Multifidelity co-kriging metamodeling based on multivariate data fusion for dynamic fit improvement of injection mechanism in squeeze casting

To improve the dynamic fit the injection mechanism in a squeeze casting machine, this paper proposes a novel multifidelity co-kriging (MFCK) metamodeling method, which fuses high-fidelity measured data with low-fidelity simulated data and considers data uncertainty and multivariate correlation influence to accurately predict response values when experimental sample data are insufficient. An MFCK model was established to predict the deformation and dynamic fit clearance, by selecting experimental and simulated values of deformation and temperature as the principal and covariates for correlation testing. The results indicate that the proposed MFCK model significantly improved the prediction accuracy by 34.18 %, 73.53 %, 41.57 % and 37.93 %, respectively, compared with the ordinary kriging model and finite element method. This method was applied to the multicycle injection process of a 2,500-kN squeeze casting machine, revealing the variation law of the fit clearance. The MFCK model improved the prediction accuracy of the fit clearance by 72.7 %, which is beneficial for process control. The accuracy and industrial applicability of the proposed MFCK method was thus verified.

Характеристики низьколегованого чавуну для формокомплектів у склотарній галузі

The growth of national production of glass packaging products requires the use of new materials and technologies to create conversion conditions for the production of moulds and their introduction into production to replace similar imported products. The main problem faced by glass packaging manufacturers when operating moulding systems is their low service life and failure due to cyclic exposure to high temperatures. The operating environment of a moulding set is caused by the aggressive action of glass material with high adhesive properties, which, in long-term contact, causes defects on the surface of the moulds in the form of oxidised areas and cracks The high moulding speed and temperature of the aggressive working environment prompts the correction of mould properties, specifically the selection of a chemical composition of a material with a low content of alloying elements, which will improve the performance characteristics of moulds and economic indicators of production. The paper presents the preparation of the chemical composition of low-alloy cast iron, determines its critical points of phase transformation, establishes its heat resistance characteristics, and recommends it for use as a moulding material. The results of the differential thermal analysis show that the onset of phase transformations in the experimental cast iron is 17.7 °C higher than the critical point of the sample from the disused mould. The change in the specific mass of the samples after 50 hours of scale resistance tests was determined, which is at a high level and amounts to 0.164 g/(cm2·h). It has been identified that the growth resistance of cast iron has linear dependencies with increasing influence of cycles, which indicates the absence of sharp phase transformations and, as a result, the absence of dynamic changes in the material during operation. It was identified that the destruction of the experimental cast iron samples occurs at the 60th cycle of high test conditions, which demonstrates positive crack resistance and the presence of a stable structure of the experimental cast iron.

THERMODYNAMIC AND EXPERIMENTAL STUDIES ON THE INFLUENCE OF HIGH-ASH COAL IN THE PRODUCTION OF HIGH-CARBON FERROCHROME

This paper presents the results of scientific research that served as the foundation for developing a technology for producing high-carbon ferrochrome using a new reducing agent in the charge-high-ash coal from the "Saryadyr" deposit. To analyze the carbothermic reduction of chromium, a method of complete thermodynamic modeling (CTM) of metallurgical processes was employed, implemented using the HSC Chemistry 10.0 software package over a temperature range of 600-2800 K. The thermodynamic analysis demonstrated that the production of carbon ferrochrome using high-ash coal does not lead to sharp technological deviations: the process proceeds stably, ensuring complete reduction of chromium and iron. An analysis of the silica and alumina content in the coal ash indicated that it can replace quartzite in the charge mixture. Based on the thermodynamic data, experimental studies of the high-carbon ferrochrome production process using Saryadyr high-ash coal were conducted in a high-temperature Tammann laboratory furnace. The Tammann resistance furnace is a research facility designed to model metallurgical processes at high temperatures. During the laboratory tests, experimental samples of high-carbon ferrochrome corresponding to grade FeCr800 were obtained.

Application of aluminum nanoparticles in reagents for oil viscosity reduction

The problem of extracting hard-to-recover reserves, which belong to the category of heavy and highly bound oil, is one of the most pressing oil industries. Many mining companies actively use physical and chemical methods to solve this problem. The use of nanotechnology in physical and chemical methods for increasing oil production is a relatively new area. Nanoparticles easily enter the regime, their size allows them to spread more easily in porous media without reducing permeability. The main goal of the research was to reduce oil viscosity and achieve increased production. In order to increase oil recovery, the proposed method for reducing oil viscosity in reservoir conditions based on treating the bottomhole zone of production wells with a solution of caustic soda and nanoparticles affects the dimension of 40-60 nm (concentrations of 1, 0.1 and 0.01 %). The nanoparticles were obtained using an electrical conductor method and studied by transmission electron microscopy. Determination of surface tension using a DSA30 device (Kruss, Germany) using the pendant drop (PD) method. The samples for testing were oil samples, visible wells No. 222761 Binagadi-North, No. 220051 Fatmai area and No. 221937 Kirmaki area, trading company "Binagadi Oil". Based on experimental data, it was found that the proposed composition reduces the viscosity of oil by several times in all three experimental samples, nanoparticles have a positive effect on reducing viscosity, the greatest effect was noted with 0.01% nanoparticles, this composition can be used to increase the production of high-viscosity oils. Keywords: nanotechnology; metal nanoparticles; enhanced oil recovery; reduce oil viscosity.

The Influence of the Make A Match Type Cooperative Learning Model on the Collaboration Ability and Learning Outcomes of Class V Students of UPT SPF SDN Mangkura I Makassar City

The objectives of this research are as follows: (1) to explain the learning process for science subjects using the Make A Match type cooperative learning model for class V UPT SPF SDN Mangkura 1 students, (2) to show how to use the Make A Match type cooperative learning model in The science and science subject has an impact on the ability to work together in class V students of UPT SPF SDN Mangkura 1, and (3) shows how the use of the Make A Match type cooperative learning model in the science and science subject has an impact on this research. This research uses quantitative methods. The type of research used is experiments with original experimental designs and control-only experiments using experimental and control classes. In this research, the experimental sample was class V A students, and the control group was class V B students. Data collection techniques used observation, tests and documentation. Analysis of learning abilities, analysis of learning outcomes, and hypothesis testing are used to analyze the data that has been collected further (t test). The results of the research show that the make a match cooperative learning model can influence students' ability to learn to work together in class V science subjects at UPT SPF SDN Mangkura. This can be seen from students who are very involved in the problem solving and learning process. Learning outcomes in class V science subjects at UPT SPF SDN Mangkura can be influenced by the make a match cooperative learning model. This can be seen from the students' seriousness during the learning process by listening to the lesson material presented by the teacher, which helps students understand the material and improve their learning outcomes.

Development of technology for obtaining tablets by double granulation method with Pipsissewa (Chimaphila Umbellata) extract

The use of the therapeutic potential of medicinal plants is currently considered a physiological method of prevention and treatment, which affects the normalization of metabolic processes and the restoration of the body's functional capabilities. Medicinal products created based on plants can be used for a longer period, including in the treatment of chronic diseases. The aim of the work is to select a technology to produce tablets containing wintergreen umbrella herb liquid extract, considering the pharmaco-technological properties of the resulting dosage form. Materials and methods. The objects of the study were pipsissewa herb liquid extract and experimental model samples of mixtures of this plant substance with excipients permitted for medical use. The research on the analysis of the liquid extract and pharmaco-technological indicators of test samples of tablet mass and tablets was carried out according to the methods of the State Pharmacopoeia of Ukraine (SPhU). Determination of the optimal technology for obtaining and quantitative composition of excipients of tablets from pipsissewa herb liquid extract was carried out using mathematical design of experiments (MDE) by the method of a four-factor experiment based on the Greco-Latin square. Results. The analysis of the liquid extract of pipsissewa showed the presence of 47.0±1.0 % of extractive (dry residue) substances. It was determined that the use of Liquid-Solid technology in the technology of obtaining tablets with plant extract based on the amorphous form of magnesium aluminometasilicate (Neusilin US2) requires the use of a combined approach that will ensure the quality of the finished product. During experimental studies, the use of three interrelated production strategies was proposed. In the process of applying the proposed strategy, it was determined that microcrystalline cellulose effectively performs the function of an adsorbent and filler; the consistency of the mixtures significantly depends on the ratio of MCC 101:extract. It was investigated that the use of double granulation will allow for the increase of the amount of active ingredient in the granulate without changing the volume of MCC 101, which will allow for the achievement of a higher extract content in the finished tablets. The use of double granulation technology can also ensure uniform distribution of the active ingredient and maintain the necessary flowability of the mixture for subsequent tabletting. The use of mathematical, experimental planning in the development of double granulation (drying) technology and the composition of excipients based on studies of the fluidity of the tabletting mass; attrition, disintegration, resistance of tablets to crushing, and organoleptic indicators became the basis for the development of the composition of the medicinal product in the form of tablets containing pipsissewa liquid extract. Conclusions. The adsorption property and its influence on the tabletting process of the synthetic amorphous form of magnesium aluminometasilicate (Neusilin US2) and microcrystalline cellulose 101 (MCC 101) were determined when using these substances as a carrier for pipsissewa grass liquid extract. The possibility of conducting a double granulation process using microcrystalline cellulose 101 (MCC 101) according to a given amount of liquid extract was proven. Using mathematical planning of the experiment, the drying conditions of the granulate and the quantitative composition of excipients were selected

Explore the viability of utilizing jackfruit leaves (Artocarpus heterophyllus) as a sustainable resource for the production of particleboard for interior applications

This research investigates the potential of utilizing jackfruit leaves as a sustainable material for particle boards in interior applications. With the increasing concern for environmental sustainability and the need for alternative materials in the design industry, exploring natural resources like jackfruit leaves offers a promising avenue.The study begins with a comprehensive literature review, examining the availability, properties, and environmental impact of jackfruit leaves, as well as the standards of a particle board. The research methodology involves experimental sampling, data collection, and analysis, supplemented by a survey to assess viability and preferences. Key findings include the identification of optimal ratios of jackfruit leaves, water, and adhesive for particle board formation, along with physical and mechanical properties testing to evaluate suitability. Additionally, the research examines the aesthetic appeal and practicality of jackfruit leaf particle boards in interior design contexts.The results demonstrate that jackfruit leaves can indeed be utilized effectively, yielding particle boards with comparable properties to traditional materials. This study contributes to the growing body of research on sustainable materials and offers practical insights for the utilization of agricultural waste in manufacturing processes.

Immunohistochemical Localization of Epidermal Growth Factor Receptor in Rat Buccal Mucosa Treated with Fenugreek Leaf Oil

The lack of effective treatment for oral mucosal ulcers has motivated clinicians to search for other therapeutic techniques to improve oral ulcer healing. Applying fenugreek to an ulcer triggers the release of its anti-inflammatory components, that might reduce any superfluous inflammatory processes and accelerate wound healing. The aim of this study was to investigate the effect of fenugreek leaf oil on the ulcer associated with the expression of epidermal growth factor receptor (EGFR). A total of 24 adult male rats weighing between 350 and 450 grams and 4-6 months of age were used in this study. The experimental design included: the normal group (no ulcer), the control group (12 ulcers left without treatment to the right), and the study group (12 ulcers on the left side were healed using fenugreek oil). All rats were sacrificed on the 3rd and 7th days of the experimental study, healing durations, and biological samples were prepared for histological and immunohistochemistry analysis of EGFR. The current study exhibited that the EGFR expression increased in ulcer sites treated with fenugreek after 3 days of ulceration with significant differences in comparison with other groups. In conclusion, fenugreek oil was efficient in promoting ulcer healing by enhancing epithelization. Moreover, the positive localization of EGFR increased in the study groups treated with fenugreek oil indicating its potential activity in accelerating the healing process‎‎‎.

Research of the method of selective laser sintering for strengthening soil tillage working organs

One of the technologies for increasing the service life of working bodies is applying a hardening layer with a material that is more resistant to wear. The study was conducted to evaluate the efficiency of the selective laser sintering (SLS) method for hardening soil-cultivating working bodies. The plasma-powder surfacing method was considered as a comparison option. The studies were conducted on a circular soil test bench, which was a rotor with racks rotating in a cylinder filled with an abrasive medium for rapid surface wear, on which samples were attached. Four experimental samples made of 30KhGSA steel were studied. The dimensions of the hardening layer were determined by calculation. After that, it was applied with P6M5 metal powder using the SLS method to 2 samples, one was hardened before heat treatment, the second after. Similarly, but using FBH-6-2 powder, 2 samples were made using plasma-powder surfacing. The bench test duration was 152 h. The linear wear of the samples when hardened by the SLS method before heat treatment was 1.3 mm, after heat treatment – 0.83 mm, by the plasma method – 1.1 mm and 1.2 mm, respectively. The hardness values that stand out from the others, with the SLS method are observed in the hardening layer zone: the sample before heat treatment is 65 HRC, after it – 73 HRC. With the plasma method, the difference in hardness is observed in the zone near the hardening layer: before heat treatment – 45 HRC, after – 35 HRC. The use of the selective laser sintering method for hardening the blade part of the experimental samples ensured a decrease in the consumption of metal powder, in comparison with the plasma method, by 32 %, an increase in wear resistance of the samples according to the calculated data – by 26 %, on the circular soil stand – by 24 %.

Quantitative Analysis of Dietary Vitamin A Metabolites in Murine Ocular and Non-Ocular Tissues Using High-Performance Liquid Chromatography.

G protein-coupled receptors (GPCRs) are a superfamily of transmembrane proteins that initiate signaling cascades through activation of its G protein upon association with its ligand. In all mammalian vision, rhodopsin is the GPCR responsible for the initiation of the phototransduction cascade. Within photoreceptors, rhodopsin is bound to its chromophore 11-cis-retinal and is activated through the light-sensitive isomerization of 11-cis-retinal to all-trans-retinal, which activates the transducin G protein, resulting in the phototransduction cascade. While phototransduction is well understood, the processes that are involved in the supply of dietary vitamin A precursors for 11-cis-retinal generation in the eye, as well as diseases resulting in disruption of this supply, are not yet fully understood. Once vitamin A precursors are absorbed into the intestine, they are stored in the liver as retinyl esters and released into the bloodstream as all-trans-retinol bound to retinol-binding protein 4 (RBP4). This circulatory RBP4-retinol will be absorbed by systemic organs, such as the liver, lungs, kidney, and eye. Hence, a method for the quantification of the various metabolites of dietary vitamin A in the eye and systemic organs is critical to the study of proper rhodopsin GPCR function. In this method, we present a comprehensive extraction and analytical method for vitamin A analysis in murine tissue. Through normal-phase, high-performance liquid chromatography analysis, all relevant isomers of retinaldehydes, retinols, and retinyl esters can be detected simultaneously through a single run, which allows for the efficient use of experimental samples and increases internal reliability across different vitamin A metabolites within the same sample. With this comprehensive method, investigators will be able to better assess systemic vitamin A supply in rhodopsin GPCR function.

Biomechanical study of two different fixation methods for the treatment of Neer III proximal humerus fractures

BackgroundThe lateral locking plate for the proximal humerus is currently the most commonly used surgical procedure for the treatment of elderly proximal humeral comminuted fractures. Previous studies have found that the rate of postoperative complications in patients of proximal humerus fractures with medial column involvement is relatively high. Through biomechanical methods, this study aims to investigate the effectiveness of the conventional lateral locking plate fixation along with the addition of the metacarpal supporting plate on the medial column in the treatment for proximal humeral fractures involving the medial column. The goal is to reduce the rate of postoperative internal fixation failure in patients with medial column injury.MethodsThirty artificial synthetic humerus models are used as experimental samples. A proximal humerus fracture model with medial column injury was created, and then divided into two groups. Group A was fixed with a proximal humerus lateral locking plate (single-plate group). Group B was fixed with a proximal humerus lateral locking plate and a metacarpal supporting plate on the medial column (double-plate group). The failure displacement, stiffness, and strength of the repaired proximal humerus fractures with two different methods were tested under compression at posterior extension of 15°, forward flexion of 15°, and vertical direction.ResultsThere was no statistical significance in the comparison of the failure displacement of repaired proximal humeral fractures between the two groups under compression at posterior extension of 15° and forward flexion of 15° (P > 0.05). However, the failure displacement of the fracture was longer in single-plate group than in double-plate group under compression at vertical direction (P < 0.05). The double-plate group was better in terms of biomechanical stiffness and strength compared to the single-plate group at all three testing angles (P < 0.05).ConclusionsFor patients whose proximal humeral fractures involve the medial column, the addition of a support plate on the medial side of the humerus is recommended along with the lateral locking plate. The double-plate strategy can increase the stability of the medial column of the proximal humerus, and enhance the overall biomechanical property of the repaired proximal humerus.

Study of the Influence of Modification and Heat Treatment of Cast Iron Grinding Balls on Their Operational Properties

The study addresses the enhancement of wear resistance and impact strength of cast iron grinding balls used under intensive abrasive wear and impact conditions at ore processing plants. The primary aim is to improve the operating properties of cast iron by optimizing its chemical composition and introducing advanced thermal and chemical-thermal treatment methods, including controlled cooling. To achieve this goal, two alloyed cast iron compositions with added chromium, molybdenum, and nickel were used, and the base composition was further modified with titanium and titanium carbonitride to increase the microhardness of the matrix phases. Experimental samples underwent various heat treatment regimes, including quenching and normalization, to evaluate the effect of these processes on the microstructure, hardness, and impact resistance of the grinding balls. Microstructural analysis revealed that additional alloying elements and modifiers contributed positively to forming a more homogeneous and fine-grained structure with an increased proportion of carbide phases. The key findings indicated that the optimized structure of the cast iron grinding balls achieved 10 units higher hardness and 2-4 units greater impact resistance than the base composition after heat treatment. Furthermore, titanium and titanium carbonitride modifications enhanced the performance characteristics of the balls by several additional units. Thus, the developed treatment regimes and modified cast iron composition significantly increase the wear resistance of grinding balls, contributing to reduced grinding costs in industrial applications.

Pomegranate Peel Extract Fortified Yogurt: Effect on Physicochemical, Microbiological and Sensory Quality of Functional Dairy Product

Background: The study aimed to evaluate the effect of incorporating Punica granatum (pomegranate) hydroethanolic extract as a functional ingredient in yogurt on the physicochemical, sensory quality and microbiological count of freshly prepared and refrigerated stored (4°C) yogurts. Methods: Pomegranate peels were dried, ground and extracted with 70% ethanol, then concentrated using a rotary evaporator and finally lyophilized to obtain pomegranate peel powder (PPP). Yogurts were prepared using pasteurized semi-skimmed cow’s milk, with phenolic extracts of pomegranate peels added at 10.0 mg, 20.0 mg and 30.0 mg per 100 mL of milk; a control product was simultaneously prepared without such pomegranate peel extract. The physicochemical analysis included pH, acidity, syneresis and viscosity measurements. Microbiological analysis was performed to determine the viability of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. Sensory scoring of the yogurt was carried out by 25 panelists using a 5-point scale. Result: Initial pH values of freshly prepared yogurt ranged between 4.48 and 4.64, decreasing to pH values of 4.3 and 4.15 at 21st day of refrigerated (4°C) storage. The titratable acidity of yogurt increased from initial value of 75°D for freshly prepared control product to 99°D as noted on 21st day of storage. Syneresis at the 21st of storage were 35.98%, 37.88%, 39.34%, 39.22% for yogurt samples control, experimental yogurt containing PPE of 10.0 mg, 20.0 mg and 30.0 mg respectively. The viscosity of yogurt utilizing 10.0 mg PPE peaked to value of 769.63 cP on 21st day of storage. Streptococcus thermophilus count peaked to 8.39 log CFU/g for experimental sample containing 10.0 mg of PPE as noted on 7th day of storage. Yogurt samples containing 20.0 mg and 30.0 mg of PPE received the superior overall acceptability scores over others. The extract improved yogurt’s physicochemical and sensory properties, enhancing its nutritional value and consumer acceptance.