Low Plate Research Articles

Lap Joint on St.37 Steel Plate with Friction Welding Clamping Method

Friction stir (FW) welding is a relatively fresh method that was created and has been continually refined and adapted to industrial applications due to its benefits. This approach for solid-state joining entails connecting the components at a temperature below their melting point and then heating them up. Clamp joint applications are widely used using external heating and hitting with high strength, but the clamped joints with the FW method are rarely done. The research studied the characteristic of clamped joints at various plate thicknesses using the FW method. In this study, 30 specimens were used in the form of a St.37 low carbon steel plate with a size of 50 mm x 100 mm and a thickness of 3 mm, 5 mm, and 9 mm, and several holes were made with a diameter of 5 mm. The plate was connected by 2 clamps, and 4 clamps then the FW method was conducted in a milling machine. The results indicate that the plates were connected well. The highest hardness value was 256.4 VHN on the FW of 9 mm plate. The microstructure is dominated by ferrite and a little pearlite phase. The largest shear force is 66.54 kN obtained at 4 clamps with a plate thickness of 9 mm, and the lowest is 13.46 kN, obtained at 2 clamps with a plate thickness of 3 mm.

Study on the interaction and motion patterns of squirmers swimming in a shear flow

In order to study the dynamic characteristics of micro-organisms or engineered swimmers, the simulations of the motion and interaction of a pair of squirmers in a shear flow are conducted using the lattice Boltzmann method (LBM) in the range of squirmer-type factor −5 ≤ β ≤ 5, self-propulsion strength 0.1 ≤ α ≤ 0.8, initial spacing between two squirmers 0.5d ≤ d′ ≤ 3d (d is the diameter of the squirmers). The interactions and motion mechanisms of squirmers in puller–puller, pusher–pusher, puller–pusher, and pusher–puller configurations are analyzed. The results show that there are three typical motion patterns in the puller–puller configuration, i.e., steady tilting motion (STM), large-amplitude oscillation motion (LAO), and small-amplitude oscillation motion (SAO). The motion of pullers has a large vertical range, and the swimming angle continues to increase in the LAO, while the pullers oscillate near the plate and have a small range of changes in swimming angles in the SAO. The situation is more complex in the pusher–pusher configuration, and there are five motion patterns, i.e., STM, LAO, SAO, limit cycle motion (LCM), and open limit cycle motion (OLCM). Three different STMs are found according to the pressure distribution around the pushers. d′ is an important parameter affecting the interaction of squirmers. In the puller–puller configuration, the backflow area on the right side of puller 1 is completely suppressed when d′ = 0.5d, but this suppression gradually weakens as d′ increases. Changes in d′ result in the differences in the final motion patterns of pullers on the upper and low plates. In the pusher–pusher configuration, changes in d′ result in transitions between different motion patterns. There exist a critical swimming angle θc when d′ changes, and the pattern changes from the STM to the LCM when θ > θc. At d′ = 0.5d, in the puller–pusher configuration, there exists a stable structure formed by the mutual repulsion caused by the high pressure area between the puller and pusher. In the pusher–puller configuration, there is a low-pressure area on one side of the pusher, which attracts the low-pressure area on the head of the puller and affects their subsequent motion patterns.

A low cost IoT-based Arabic license plate recognition model for smart parking systems

License Plate Recognition is one of the significant enablers that can be utilized in wide range of applications in ITS and smart cities. The proposed design relies on three image processing stages to achieve license plate identification with high accuracy which are pre-processing, segmentation, and character recognition. The canny edge detection method with various thresholds, contour detection, and masking techniques are used to locate the car edges and license plate. In the experiment presented in this paper, 200 images were used to identify Egyptian car plates. The model successfully identified Arabic license plates with 93% accuracy. A prototype is implemented using ESP32 Cameras and Raspberry-Pi to test the system's performance. Moreover, a database and a website are hosted on the RPi to allow users to search for their car location in the parking lot using the car's full or partial license plate which was saved in database upon detection.

Characterization of ultrafine grain tungsten carbide tool and its wear investigation in friction stir welding of HSLA steel

In this work, cemented carbides with different cobalt content were developed by using medium and ultrafine tungsten carbide grains. The GGI, (Cr3C2), was added in small amount (0.5 wt. %) to restrict the grain growth. The effect of particle size, reinforcement content and sintering temperature on metallography, densification and mechanical properties is investigated. At 1680 ºC, Co phase was uniformly distributed at WC interface by particle rearrangement and resulted in fully dense microstructure. The fine particle enhanced the sintering rate due to large specific surface area and surface energy. The developed tool was used to join 4 mm thick high strength low alloy steel plates without severe wear and degradation of the tool. Tool oxidation and interface degradation associated to extreme tribological welding condition is observed.

Abstract 1749: The synergic effect of cisplatin and a chemokine receptor antagonist sensitizes drug resistant gastric cancer cells and inhibits tumoroid formation

Abstract Introduction: Gastric cancer (GC) is an important cause of death worldwide. Cisplatin (CDDP) is the most used drug in the chemotherapy of advanced GC. However, CDDP resistance reduces GC survival. The CCR5/CCL5 axis has been associated with GC development, but its role in CDDP resistance in GC has not been elucidated. The aim of this study was to determine the effects of CCR5/CCL5 axis blockade by a chemokine receptor antagonist (CRA), alone and in combination with CDDP, on in vitro and 3D tumorid models from AGS R-CDDP cells. Methodology: AGS R-CDDP cells (CDDP-resistant human gastric adenocarcinoma cells) were previously established using a stepwise drug dosing protocol and characterized. CCL5 was selected through transcriptomic analysis and its expression level was validated by qRT-PCR. Cytotoxicity assays were determined by using MTT. Apoptosis and cell cycle assays were evaluated by flow cytometry. Tumoroid formation was performed from AGS R-CDDP cells in low adhesion plates (NunclonTMSpheraTM). After 10 days in culture, tumoroid >150 µm in diameter were scored and pharmacological stimuli were added on days 14, 17 and 20. CRA was used alone and in combination with CDDP in all assays. Results: CRA/CDDP combination triggered a re-sensitized phenotype in AGS R-CDDP cells, decreasing cell viability but not increasing apoptosis compared to independent treatments. AGS R-CDDP cells treated with CRA/CDDP were mainly arrested in S phase. CCL5 showed a decrease in mRNA levels after the CRA/CDDP combination compared to separate treatments. AGS R-CDDP cells showed a higher potential in the ability to form tumoroids compared to AGS WT cells. Finally, CRA/CDDP combination inhibited tumoroid formation compared to independent treatments. Discussion and Conclusion: CCL5 showed a decrease in mRNA levels after the CRA/CDDP combination, possibly correlating with allosteric inhibition of the CCR5 receptor. CRA/CDDP combination has a synergic effect that sensitizes AGS R-CDDP cells and inhibits tumoroid formation. This combination could be used as a potential coadjuvant in GC therapy allowing to reduce the doses of CDDP and therefore to reduce side effects. Citation Format: Bárbara Mora-Lagos, María Elena Reyes, Lorena Lobos-Gonzalez, Matías del Campo, Carmen Gloria Ili, Kurt Buchegger, Yuselin Mora, Louise Zanella, Ismael Riquelme, Priscilla Brebi. The synergic effect of cisplatin and a chemokine receptor antagonist sensitizes drug resistant gastric cancer cells and inhibits tumoroid formation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1749.

Chemical reprogramming of human embryonic fibroblasts into neural progenitor cells in vitro

To establish a protocol for reprogramming human embryonic fibroblasts (HEFs) into chemically induced neural progenitor cells (ciNPCs). In the two-staged reprogramming of HEFs, the intermediate compact cell colonies were first chemically induced in KSR medium containing small-molecule compounds (VCR) for 15 days in normoxia, followed by the lineage-specific induction stage, in which the compact cell colonies were digested with 0.25% trypsin and the cells were cultured in low adhesion plates. After formation of a large number of free-floating neurospheres 2 days later, the ciNPCs were labeled with CM-DiI and transplanted into rat models of Parkinson's disease (PD)to observe the survival, migration and differentiation of the cells in PD brain. After induction with VCR for 10 days under normoxic condition, compact cell colonies occurred in HEF cultures (approximately 40 colonies in each well containing 1×105 HEFs), and most of the colonies expressed high levels of alkaline phosphatase. A large number of free-floating neurospheres formed 2 days after passage and were defined as P1 ciNPCs. These ciNPCs exhibited typical neurosphere-like structures and expressed NPC-specific markers (nestin, Sox2, and Pax6). Under neuronal or glial differentiation condition, the ciNPCs expressed the neuron-specific marker Tuj1 and the astrocyte-specific marker GFAP. These ciNPCs could differentiate into Tuj1+, GFAP+, TH+ and GABA+ cells 4 weeks after transplantation into the brain of PD rats. HEFs can be directly reprogrammed into ciNPCs using smallmolecule compounds without the need of introducing exogenous genes. This success may provide a solution to the shortage of donor materials for neuroscience research and treatment of neurodegenerative diseases.

Milk from Halari Donkey Breed: Nutritional Analysis, Vitamins, Minerals, and Amino Acids Profiling

This current research set out to characterize Halari donkey milk by investigating its nutritional constituents, including its proximate analysis, water activity, titratable acidity, energy, and microbiological analysis. A comprehensive profiling of vitamins, minerals, and amino acids was also carried out. It was found that the composition of Halari donkey milk was consistent with previously published donkey milk literature and was comparable to that of human milk. Halari donkey milk has low 0.86 ± 0.04% fat content, 2.03 ± 0.03% protein content, 0.51 ± 0.05% ash content, and high 5.75 ± 0.15% lactose content making it sweet and palatable. The energy content of Halari donkey milk was 40.39 ± 0.31 kcal/100 g, and the water activity ranged from 0.973 to 0.975. Titratable acidity was 0.03 ± 0.01%. Halari donkey milk can be considered acceptable and microbiologically safe, having low total plate count and yeast and mould counts. Mineral testing revealed that Halari donkey milk included significant amounts of magnesium, sodium, calcium, potassium, phosphorus, and zinc. The concentration of different vitamins and amino acids such as isoleucine and valine also contribute to the nutritional value of Halari donkey milk.

Three-Dimensional (3D) in vitro cell culture protocols to enhance glioblastoma research.

Three-dimensional (3D) cell culture models can help bridge the gap between in vitro cell cultures and in vivo responses by more accurately simulating the natural in vivo environment, shape, tissue stiffness, stressors, gradients and cellular response while avoiding the costs and ethical concerns associated with animal models. The inclusion of the third dimension in 3D cell culture influences the spatial organization of cell surface receptors that interact with other cells and imposes physical restrictions on cells in compared to Two-dimensional (2D) cell cultures. Spheroids' distinctive cyto-architecture mimics in vivo cellular structure, gene expression, metabolism, proliferation, oxygenation, nutrition absorption, waste excretion, and drug uptake while preserving cell-extracellular matrix (ECM) connections and communication, hence influencing molecular processes and cellular phenotypes. This protocol describes the in vitro generation of tumourspheroids using the low attachment plate, hanging drop plate, and cellusponge natural scaffold based methods. The expected results from these protocols confirmed the ability of all these methods to create uniform tumourspheres.

Microstructure and Hardness Properties of Hardfacing Overlays Deposited by Shielded Metal Arc Welding on Low Carbon Steel Plate

The aim of this study is to investigate the effect of applying various welding current parameters of shielded metal arc welding (SMAW) on microstructure and the hardness of the hardfacing overlays. The investigation was performed on a 12mm thick ASTM A36 steel plate weld overlaid by hardfacing electrode HV-450 of 3.2 mm diameter at various welding currents, 90, 110, and 130 amperes, respectively. The investigation was conducted by using optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and hardness test on the hardfacing overlay. The results showed the hardness of the hardfacing overlay is higher than the base metal, indicating higher strength of the weld overlay. From the three welding currents applied, the highest hardness in the weld overlay is obtained at the lowest current.

New genus and species of the family Aeduellidae (Actinopterygii) from the Lower Goldlauter Formation (Asselian, Lower Permian) of the Thuringian

A new aeduellid actinopterygian Amelangia ornata gen. et sp. nov. is described from the Lower Goldlauter Formation of the Thuringian Forest (Lower Permian, Germany). Distinguishing characters of the newly described taxon are a large dermosphenotic, an unusually large number of suborbital bones, a maxilla with a low maxillary plate, a distinct sculpture consisting of tubercles on the operculum and suboperculum, the presence of a single branchiostegal ray, and a pectoral fin with a scaly basal lobe. The preserved characters place the new genus close to the genera Aeduella and Bourbonnella. The newly described genus and species is similar to an isolated operculum and suboperculum recovered from the Lower Permian of the Krkonoše Piedmont Basin in the Bohemian Massif.

Effect of submerged arc welding process on hardness and impact properties of fabricated SAE 1020 low carbon steel plates

Effect of submerged arc welding process on hardness and impact properties of fabricated SAE 1020 low carbon steel plates

Formation mechanism of surface upwarping and black line defects on low carbon hot rolled plate

To improve the surface quality of low-carbon hot-rolled steel plates, the upwarping and black line defects were investigated by means of XRF (X-ray diffractometer), OM (optical microscopy), SEM (scanning electron microscopy) and EBSD (electron back scatter diffraction). The results showed that the micro area compositions under surface upwarping and black line defects were mainly made of secondary oxide particles, steelmaking slag and mould flux respectively. According to the metallographic structure, inclusion compositions and grains texture analysis, it could be concluded that surface defects on hot rolled plates were attributed to the entrapment of ladle slag or mould flux, gas bubbles, micro-cracks of casting slab in the steelmaking process, rolled-in scale and unreasonable sizing press rolling parameters during the rolling process, and the position and formation process of typical surface defects on hot rolled plates were discussed in detail. Finally, it concluded that the slag entrapment and solidification hook should be controlled during continuous casting.

Stemness maintenance of stem cells derived from human exfoliated deciduous teeth (SHED) in 3D spheroid formation through the TGF-β/Smad signaling pathway.

Mesenchymal stem cells (MSCs) have shown great potential as important therapeutic tools for dental pulp tissue engineering, with the maintenance and enhancement of their stemness being crucial for successful therapeutic application in vivo and three-dimensional (3D) spheroid formation considered a reliable technique for enhancing their pluripotency. Human exfoliated deciduous tooth stem cells (SHED) were cultured in a low attachment plate to form aggregates for five days. Then, the resulting spheroids were analyzed for pluripotent marker expression, paracrine secretory function, proliferation, signaling pathways involved, and distribution of key proteins within the spheroids. The results indicated that 3D spheroid formation significantly increased the activation of the transforming growth factor beta (TGF-β)/Smad signaling pathway and upregulated the secretion and mRNA expression levels of TGF-β, which in turn enhanced the expression of pluripotency markers in SHED spheroids. The activation of the TGF-β/Smad signaling pathway through 3D spheroid formation was found to preserve the stemness properties of SHED. Thus, understanding the mechanisms behind pluripotency maintenance of SHED culture through 3D spheroid formation could have implications for the therapeutic application of MSCs in regenerative medicine and tissue engineering.

PERFORMANCE ANALYSIS OF A BIPOLAR PLATE IN A FUEL CELL USING COMPUTER FLUID DYNAMICS STUDIES

Over the past ten years, proton exchange membrane (PEM) fuel cells have gained popularity as a potential energy source. PEM fuel cells are a high efficiency, environmentally friendly power source that are not constrained by Carnot efficiency. Due to its characteristics of zero emissions, high power density, rapid start-up, and low operating temperature, they are seen as one of the attractive options to be utilized for electric cars. In this project work, a fuel cell uses that a low cost bipolar plate material with a high fuel cell performance are important for the establishment of PEM fuel cells into the competitive market world are taken in consideration. The analysis is carried out for the selected materials like Aluminium, Copper and Stainless steel on considering the design and operational parametric conditions of the PEM fuel cell. The aluminium bipolar plate exhibits improved uniformity in the dispersion of hydrogen, oxygen, and water vapour, which will improve the ionic conductivity in the membrane. After analysing the data, we found that the aluminium bipolar plate material had the best temperature distribution in the fuel cell and the lowest pressure loss when compared to the copper and stainless steel materials. Therefore, due to its light weight and reasonably low price of material, aluminium serpentine bipolar plate material may be thought of as the ideal bipolar plate material, especially for portable applications.

Spheroids as a 3D Model of the Hypoxic Tumor Microenvironment.

Spheroids enable the study of tumors and tumor hypoxia using a more representative model of the physiological environment compared to 2D cell culture. Spheroids can be grown in a cell suspension or when adhered to a solid scaffold. The spheroid formation method used is dependent on cell type. Here we describe the most common spheroid formation methods, including hanging drop, low adhesion plates, hydrogel, micropatterned plates, and microfluidics. After spheroids are formed, they can be used for drug treatment trials and analyzed using Western Blots, qPCR, and microscopy. Microscopy can then be used to measure the invasiveness of cells when a basement membrane is added to spheroids and for monitoring changes in the proliferation, quiescent, and necrotic zones of spheroids.

Surface Properties of the Polyethylene Terephthalate (PET) Substrate Modified with the Phospholipid-Polypeptide-Antioxidant Films: Design of Functional Biocoatings.

Surface properties of polyethylene terephthalate (PET) coated with the ternary monolayers of the phospholipid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), the immunosuppressant cyclosporine A (CsA), and the antioxidant lauryl gallate (LG) were examined. The films were deposited, by means of the Langmuir-Blodgett (LB) technique, on activated by air low temperature plasma PET plates (PETair). Their topography and surface chemistry were determined with the help of atomic force microscopy (AFM) and time-of-flight secondary ion mass spectrometry (TOF-SIMS), respectively, while wettability was evaluated by the contact angle measurements. Then, the surface free energy and its components were calculated from the Lifshitz-van der Waals/Acid-Base (LWAB) approach. The AFM imaging showed that the Langmuir monolayers were transferred effectively and yielded smoothing of the PETair surface. Mass spectrometry confirmed compatibility of the quantitative and qualitative compositions of the monolayers before and after the transfer onto the substrate. Moreover, the molecular arrangement in the LB films and possible mechanisms of DOPC-CsA-LG interactions were determined. The wettability studies provided information on the type and magnitude of the interactions that can occur between the biocoatings and the liquids imitating different environments. It was found that the changes from open to closed conformation of CsA molecules are driven by the hydrophobic environment ensured by the surrounding DOPC and LG molecules. This process is of significance to drug delivery where the CsA molecules can be released directly from the biomaterial surface by passive diffusion. The obtained results showed that the chosen techniques are complementary for the characterization of the molecular organization of multicomponent LB films at the polymer substrate as well as for designing biocompatible coatings with precisely defined wettability.

Local corrosion morphology analysis and simplification of low carbon steel plates

This paper focuses on the surface morphology of low carbon steel plates with local corrosion. Copper-accelerated acetic acid salt spray tests were carried out on 24 steel plate specimens with different corrosion parameters, and then the 3D morphology of the steel plate surfaces after corrosion was observed, extracted and analyzed. According to the statistical analysis of the surface depth of the corrosion morphology, the local corrosion surface can be divided into the central flat corroded zone and edge corroded zone, and the width of the edge corroded zone almost keeps constant regardless of the corrosion area. The 3D morphology of the corroded specimens was imported into ABAQUS software to develop finite element models, and the numerical results were compared with the tensile test results of the corroded steel plates, showing good agreement. Finally, based on the finite element analysis, it is suggested that local corrosion of steel plates can be simplified into a region with uniform depth, whose depth is determined as the average corrosion depth of the locally corroded region. The maximum errors of prediction results of yield strength, ultimate strength and ultimate strain between the simplified model and the actual morphology model were 0.03%, 1.8% and 20%, respectively.

Comparison of Lugol’s solution and Fe3O4 nanoparticles as contrast agents for tumor spheroid imaging using microcomputed tomography

Abstract Background Lugol’s solution is well known for its unique contrasting properties to biological samples in in microcomputed tomography imaging. On the other hand, iron oxide nanoparticles (IONPs), which have much lower attenuation capabilities to X-ray radiation show decent cell penetration and accumulation properties, are increasingly being used as quantitative contrast agents in biology and medicine. In our research, they were used to stain 3D cell structures called spheroids. Aim In this study, the micro computed tomography (µCT) technique was used to visualize and compare the uptake and accumulation of two contrast agents, Lugol’s solution and iron (II, III ) oxid e nanoparticles (IONPs) in the in vitro human spheroid tumour model. Methods The metastatic human melanoma cell line WM266-4 was cultured, first under standard 2D conditions, and after reaching 90% confluence cells was seeded in a low adhesive plate, which allows spheroid formation. On the 7th day of growth, the spheroids were transferred to the tubes and stained with IONPs or Lugol’s solution and subjected to µCT imaging. Results Our research allows visualization of the regions of absorption at the level of single cells, with relatively short incubation times - 24h - for Lugol’s solution. IONPs proved to be useful only in high concentrations (1 mg/ml) and long incubation times (96h). Conclusions When comparing the reconstructed visualizations of the distribution of these stating agents, it is worth noting that Lugol’s solution spreads evenly throughout the spheroids, whereas IONPs (regardless of their size 5 and 30 nm) accumulate only in the outer layer of the spheroid structure.

Perancangan Alat Treker Piston Kaliper Rem Mobil Dengan Sistem Hidrolik

The hydraulic piston tracker is a tool used to press the car's caliper pistons when changing the disc pad. This study aims to design and design a piston caliper treker tool with a maximum strength of 50Kg and to determine the components and dimensions used in this tool. In this study, the main system is hydraulic which converts the pressure to be greater. The pressure produced by this tool is 50Kg or 490.5 N using only the force of the hand of 8.05 N. For the size of this tool it has an overall length of 27 cm, a retaining width of 11.5 cm, a lever length of 20 cm and a hydraulic tube diameter. 3 cm. main material for hydraulic cylinder chrome steel s30c 48 (Kg/mm2), low carbon steel plate (ST42) 36 (Kg/mm2), bolts, handles and levers Low carbon steel (ST42) 36 (Kg/mm2).Key words : Tool, Treker, design, hydraulic

Mechanical and Metallurgical Characteristics of Rotary Friction Welded Low Carbon Steel Plate/Rod Joints

This work aims to study the mechanical properties and microstructural characteristics of rotary friction welding of the unsymmetrical (plate/rod) joints of AISI 1018 low carbon steel plate and AISI 1020 low carbon steel rod. The mechanical properties (tensile properties and hardness) were studied. The fractured surface of the tensile specimen was examined by Scanning Electron Microscope (SEM). The tesnile properties (strength and elongation) are higher than the AISI 1018 plate but slightly lower than the AISI 1020 rod due to coarse ferrite grains in the HAZ region of the AISI 1018 plate. The hardness varied from the fully deformed zone (FDZ) to the base metal. The average value of the ultimate tensile strength of the friction welded joint is about 452 MPa. The average value of hardness at fully deformed zone is about 252 Hv, which 32% higher than the base metal.