Articles in This Issue
Abstract
The mixing technique was applied in this study to enhance the strength performance of the cement. The addition of 3% by weight of hydroxyapatite (HA) nanoparticles were mixed with 97% polymethyl methacrylate (PMMA) acrylic polymer, which has a nano size to serve as the matrix material. The surface roughness and continuous porosity of the bone cement were found to be slightly increased by the incorporation of nanoparticles, which enhanced bone-implant osseointegration and ingrowth. Atomic force microscopy (AFM) analysis revealed that the addition of hydroxyapatite (HAp) nanoparticles resulted in a surface roughness value (Sa) of 16.25 nm, which is similar to that of natural bone. The energy-dispersive X-ray spectroscopy (EDS) mapping results discover precentor material and uniform distribution. The Sample exhibited promising results in the antibacterial test, showing efficacy against bacteria both with and without sterilization, confirming its antibacterial properties. The mechanical tests conducted on the sample, including tensile, compression, bending and Vickers hardness tests, yielded favorable results and indicated that the sample is suitable for its intended application. In the theoretical works the design of the bone, screw, and bone plate was conducted using SolidWorks, followed by an analysis using ANSYS under both axial and bending load conditions. The theoretical analysis revealed that the safety factor was less than 1 when an axial load of 13 N was applied and a bending load of 2 N was applied, indicating that the structure may not be able to withstand these loads safely. Under both ambient and physiologically relevant conditions in the human body, HA and PMMA have demonstrated to be excellent choices for enhancing the clinical performance of bone cement. This, in turn, can lead to increased longevity of implants, decreased patient risk, and lower healthcare costs
Abstract
High-performance polymer nanocomposites utilizing different-sized nanofillers had a lot of interest recently. Due to their distinct structural, and thermal characteristics. Multi-wall carbon nanotubes (MWCNT) and nanoclay (NC) have the most interest among the numerous types of reinforcing as filler elements for a polymer. The formation of hybrid from MWCNT and NC at various loadings (0.5%, 1%, and 2wt%) on the characteristics of epoxy polymer have been assessed in this work. The specimens have been created using solution blending procedures with the addition of solvent ethanol at a ratio of 1:1 for dispersed nanofillers, and then they have been re-mixed with epoxy. Tests like X-Ray diffraction (XRD), and thermal conductivity were used to identify properties of epoxy. According to the test results, the thermal conductivity rise as the filler content rises at 1wt%, then start to decrease after 1wt%. The sample with the hybrid filler loading of 1 wt% produced the best performance. Since hybrid epoxy exhibits the best result of the thermal conductivity 135% over MWNT and NC nanocomposites of 1 wt.% reached 0.3568 W/m.K in the increased thermal conductivity property. By examining the EP nanocomposites XRD pattern. The hybrid of epoxy nanocomposites exhibits all of the NC and MWCNT characteristic peaks. Since interactions between the filler and the epoxy cause a shift in the peak location of 1wt%. Due to the homogeneity of the nanofillers entire epoxy matrix, there may be changes in the intensity or location of the peaks at 1% for 2θ= 20.13°, which corresponds to an interlayer distance of d=0.461nm.
Abstract
Biodegradable polymers are very useful polymers in biomedical applications. In this research, several hydrogels were fabricated by using two polymers, Polyvinyl alcohol (PVA) and Chitosan (Chs) by the solvent casting method in order to use them for skin applications. Several tests were carried out on these membranes such as Agar diffusion method to examine their antimicrobial activities, Fourier transform infrared microscopy (FTIR) test to study the differences in their chemical structures. Uniaxial tensile test was performed to examine the mechanical characteristics of these membranes. In addition, the wettability test was used to investigate the hydrophobicity or hydrophilicity of the surfaces. The results showed that all membranes are hydrophilic, of which the contact angles are less than 90°. The membrane manufactured from 75:25 Chs-PVA is more hydrophobic (contact angle is 74°) than other membranes made of 50:50 Chs-PVA and 25:75 Chs-PVA as the contact angles were 59° and 61°, respectively. The tensile test results indicate that the membrane fabricated of the PVA and the membrane that was fabricated by 75% Chs and 25% PVA has the highest tensile strength of 17.9 MPa, 16.2 MPa and Young^’ s Modulus of 181.2 MPa and 7.18 MPa, respectively. The highest strain at break was observed by the membrane of 25:75 Chs-PVA which equals to 24.67%. Chitosan membranes showed inhibition zones of about 2.99 cm and 2.75 cm in length, and 75:25 Chs-PVA membranes showed 5.1 and 5.91 cm in length for E.coli. To sum up, this copolymer is considered as promising hydrogel for skin applications such as wound dressing.
Abstract
In this work, environmentally friendly zinc oxide nanoparticles was produced using sustainable green technology. With several loading amounts, such as 5%, 10%, 50%, and 100%, the banana peel extract was utilized as a capping agent. This was followed by calcinations at 400 ºC for 3 h in a muffle furnace. To evaluate the physical and chemical change of the synthesized nanoparticles, XRD, FTIR, UV-VIS and SEM/EDAX was used. The characterization results reveald that the all the green synthesized ZnO NPs samples strongly supports the well-crystallinity with high phase purity. The average crystallite size of the prepared samples was calculated using Debye-Scherer's formula and the results shows that with an increase in extract amount, the average crystallite size was shrinking. The FTIR result verified the successful chemical reaction between zinc salt and banana peel extract. The UV-VIS results showed the effect of size quantisization phenomena at 100% extract adding. Finally, the SEM images for all the prepared samples confirm the spherical shape.
Abstract
The main objective of this study is to design the asphalt pavement structure for the Alkut-Mayssan highway in Iraq as a case study by using PCASE application to determine the necessary thickness of CR-modified asphaltic layers. Additionally, Marshall tests were used to investigate the effect of the dry process crumb rubber modifier on the thickness of the binder coarse layer based on various variables, such as the crumb rubber modifier with different content (1, 2, 3, 4, 5)% and sizes (0.3mm, 2.36mm , 4.75mm, and mix gradation). The test results show that while pavement thickness reduced as crumb rubber gradation increases, MR values increase. Additionally, as compared to the control mixture, the addition of 1% of CR in various gradations could decrease the thickness of the asphalt binder layer.
Abstract
Optical coherence tomography (OCT) allows for direct and immediate imaging of the morphology of retinal tissue. It has become a crucial imaging modality for diagnosing eye problems in ophthalmology. One of the most significant morphological characteristics of the retina is the structure of the retinal layers, which provides important evidence for diagnostic purposes and is related to a variety of retinal diseases. In this paper, a convolutional neural network (CNN) model is proposed that can identify the difference between a normal retina and three common macular diseases: Diabetic macular edema (DME), Drusen, and Choroidal neovascularization (CNV). This proposed model was trained and tested on an open source dataset of OCT images also with professional disease classifications such as DME, CNV, Drusen, and Normal. The suggested model has achieved 98.3% overall classification accuracy, with only 7 wrong classifications out of 368 test samples. The suggested model significantly outperforms other models that made use of the identical dataset. The final results show that the suggested model is particularly adapted to the detection of retinal disorders in ophthalmology centers.
Abstract
The presence of heavy metal pollutants in refinery effluent significantly impacts the corrosion rate of carbon steel. The focus of this research is to analyze the impact of various inorganic pollutants, including copper, vanadium, nickel, and chromium ions, on the corrosion of carbon steel across different solutions. After conducting a thorough examination of various operating conditions, including pollutant concentration (ranging from 300-3000 ppm), temperature (30-60? C), and flow velocity (0-800 rpm). Our research shows that copper ions have the highest corrosion rate, with vanadium ions being a close second. Conversely, nickel and chromium had the most negligible impact on corrosion rate and, in some instances, even exhibited corrosion inhibition effects. It was also observed that an increase in flow velocity and temperature significantly amplified the corrosion rate of the metal ions investigated.
Abstract
The assessment of prosthetic aortic valves through echocardiography, a pivotal noninvasive tool, encounters challenges, with discordant findings compared to invasive measurements, particularly in transvalvular gradients. To address these complexities, this comprehensive review article explores diverse methodologies and modalities for assessing prosthetic aortic valve performance. As these life-saving devices advance in complexity, the demand for precise and innovative assessment techniques intensifies. This journey through established and emerging modalities aims to inform clinical practice, foster experimental innovation, and enhance patient care in the realm of aortic valve prosthetic assessment. Ultimately, a profound understanding of the hemodynamic milieu engendered by aortic prosthetic valves serves as the cornerstone for optimizing valve design and clinical utility. The primary objective of this comprehensive review is to elucidate, with utmost precision, the multifaceted methodologies employed in the investigation and evaluation of mechanical prosthetic aortic valve.
Abstract
Recent research has focused on analysing megakaryocyte images to extract the information needed to track the progression of nervous system diseases. Segmentation is a fundamental step in describing and analysing the core contents of megakaryocytes, including the cytoplasm and nucleus. In this study, 45 megakaryocyte images were obtained. A new segmentation image technique was proposed, called the updating fuzzy c-means technique, through the intelligent selection of the centres of each cluster to separate cell components. The first step of this technique (fuzzification) was based on a knowledge analysis of the local parameters (entropy, contrast and standard deviation) that had a substantial influence on the grey-level distribution between the cytoplasm and nucleus. The second important step was the construction of fuzzy rules in terms of the variation in these local parameters to control the intelligent pick-out or update the centroid of each cluster and obtain a successful separation of the cytoplasm and nucleus. The final step was defuzzification to obtain the output images. The results revealed the superiority of the proposed method over recent technique. The accuracy of the segmented nucleus was greater than 7.46%; in the case of the cytoplasm, the accuracy was higher at 18%. These results indicated that this technique may be applied on other biomedical images.
Abstract
The improvement in solar chimneys' thermal performance and thermal behavior that can be achieved by adding metal foam has been tested in computational work. The flow and heat transfer governing equations for solar chimney models were solved using computational fluid dynamics (CFD). It was solved using the control volume numerical method in ANSYS FLUENT 14.5. It is used to construct a finite volume modeling technique for solving the governing equations and the radiation heat transfer equations. With standard flat absorber plates, the results showed that heat transmission was increased by the inclusion of metal foam (10 PPI), leading to an increase in air velocity at the solar chimney of around 13.3%. The highest average air velocity with 10 PPI drops by 54.4% as the height of the absorber plate changes from 5 cm to 25 cm respectively.
Abstract
Rigid pavement slabs are erected on a prepared subgrade or foundation layer, providing a hard and continuous surface. Transverse joints made of dowel bars connect them, and longitudinal joints made of tie bars join them longitudinally. This study is an investigation of the impact of soil strength and concrete parameters on the effectiveness of dowel bars in rigid pavements. Moreover, three parameters were examined; California Bearing Ratio (CBR), concrete compressive strength and slab thickness. The analysis was conducted using the Ever FE program and focused on several axle configurations applied to the joint. The results indicate inverse association between the pavement slab thickness and the concrete strength, under the assumption of consistent soil strength. Moreover, an assortment of reduced shear forces on the dowel bars is seen when the soil strength values increase. It indicates that soil strength has a greater impact on the shear load of dowel bars compared to the qualities of concrete. Additionally, the type of axles used and the magnitude of soil strength were shown to have a significant effect on the shear load.
Abstract
One of the health issues that many people encounter on a daily basis is bone fracture, which can happen for a number of reasons, such as arthritis, sprains, or external trauma . The patient experiences instability as a result of these issues . Internal fixation is a type of surgery used to support and mend a damaged bone Treatment options include ankle joint fixation, a surgical procedure employing pins, plates, rods, or screws. This study uses gait analysis methods to assess lower limb biomechanics . Gait analysis is vital for understanding walking patterns and intervention effectiveness. The impact of different shoe designs on ankle mechanics, using the finite element method and ANSYS, is investigated The results of the EMG and the GRF were discussed._x000D_ This research deepens our understanding of lower limb biomechanics and ankle joint health. By evaluating stress effects and designing custom shoes, it enhances ankle injury treatment and management strategies._x000D_ The patient, a 70-year-old woman with an internal fixation on her ankle joint, underwent a CT scan of her ankle. The patient underwent a number of experiments to evaluate her stability. EMG was used to determine the muscle stress for a brief period of time, and ground reaction force was then used to determine the pressure of walking. Both EMG and GRF have two walking speeds of1.5and 2 km/h while wearing four different types of shoes. The behavior of the EMG demonstrates that the stress on the muscle increases as walking speed increases, and the results varies depending on the shoe. The patient is afraid to apply pressure to the injured foot, so the health foot has better pressure over the entire foot_x000D_
Abstract
In recent years, nanoparticles have gained significant attention in the field of cancer treatment due to their extensive potential and wide range of uses. The research mostly focuses on the inorganic chemicals, with a specific emphasis on metals, in order to enhance the comprehension of functional nanoparticles synthesis. This undertaking is motivated by the distinctive characteristics exhibited by these materials, which provide significant advantages for both fundamental scientific inquiry and practical implementations, notably those focused on cancer. The objective of this review is to conduct a comprehensive analysis of the diverse applications of nanocomposites, with a specific focus on their utilization in medication delivery.