American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS)
Not a member yet
2107 research outputs found
Sort by
Pathological Mechanism of Atherosclerosis
Get PDFAtherosclerosis is a multifactorial, smoldering, focal (intima of bifurcated blood arteries), chronic, progressive asymptotically, immune-inflammatory, disorder driven by lipid imbalance, in the large to medium sized (upto3mm external diameter) arteries with many cardiovascular clinical manifestations. Atherosclerosis developmentinvolves many cells, organs and even disturbed blood flow. The progression of atherosclerotic disease depends on the presence, degree, and persistence of risk factors like high-fat diet, smoking, hypertension, history of heart diseases, or diabetes. Endothelial dysfunction, ROS, accumulation of LDL, recruitment of Monocytes and T cells, differentiation of monocytes into macrophages and foam cells, formation of plaque and rupturing of plaque are key steps behind the clinical manifestation of atherosclerosis in cardiovascular diseases. This article describes the pathogenesis of atherosclerosis, possibility of therapeutically targeting mechanism and interventions which can be helpful to reverse or slower the atherosclerosis.
Operation and Maintenance of Small-Scale Biogas Digesters: Scoping Review and Bibliometric Analysis of Literature
Get PDFBiogas technology has matured over the years and is gaining acceptance; however, challenges with optimum operation and maintenance of digesters are a massive hurdle for developing countries that threaten the successful adoption of the technology. The failures of biogas digesters leading to the low diffusion of the technology in developing countries have been attributed to several factors spanning from social to technical. This study employed a scoping review and bibliometric analysis to synthesize literature in the Scopus database to map and discuss scientific knowledge. The synthesized data suggest the need for real-time monitoring systems for the optimal operations and maintenance of small-scale biogas digesters. A bibliometric analysis with the VOSviewer software of the study suggested that there is limited research output from developing countries such as Ghana. It, therefore, necessitates the need for conscious commitments from stakeholders to invest resources to advance research to address the challenge.
Fighting Cybercrime with Zero Trust
Get PDFZero Trust Architecture focuses on securing critical data and access paths by eliminating trust as much as possible by “assuming breach.” It establishes trust every time a user tries to access an asset in the system by questioning the premise that users, devices, and network components should be implicitly trusted based on their location within the network. We have chosen Zero Trust to help reduce the impact of cybercrime and establish baseline security practices. It is a dramatic paradigm shift in the philosophy of securing our infrastructure, networks, and data, from verifying once at the perimeter to continually verifying each user, device, application, and transaction. Trust in humans is essential to forming connections; however, trust in network connections can create dangers and potential security gaps in the digital world. In a hyper-connected world, anyone can launch an attack virtually and participate in cybercrime by violating the trust of systems or networks. The cost of not implementing good security practices is evident in the growing number of data breaches and ransomware attacks that erode consumers\u27 trust in tech and online space. Considering Zero Trust and Zero Trust Architecture developed by the National Institute of Standards and Technology (NIST) should help reduce the impact of cybercrime and protect the crown jewels in cyberspace from a malicious insider or an external attacker
Possibility of Using Floating Solar Photovoltaics in the Hybrid Energy Systems in the Islands of El Hierro, Spain and Crete, Greece
Get PDFUse of floating solar photovoltaics in man-made water dams is an emerging sustainable energy technology worldwide. Floating solar photovoltaics reduce the land area required for their installation, reduce water evaporation from water bodies while they have higher electricity yields. Aim of the current work is the investigation of the possibility of using floating solar photovoltaics in the hybrid energy systems in the islands of El Hierro, Canary islands, Spain and in Crete, Greece. The characteristics of the existed pumped-hydro-storage system in El Hierro and the planned pumped-hydro-storage system in Crete are used for the necessary estimations. Our results indicate that the annual electricity generation from the installation of floating solar photovoltaics in the existing pumped-hydro storage system in El Hierro, with 30% coverage ratio, corresponds at 6.09% of the annual electricity generation by the hybrid energy plant and at 4.6% of the total annual electricity consumption in the island. The annual electricity generation from the installation of floating solar photovoltaics in the planned pumped-hydro storage system in Crete, with 30% coverage ratio, correspond at 296.91% of the estimated electricity generation by the hybrid energy plant and at 22.14 % of the annual electricity consumption in the island in 2018. It is concluded that installation of floating solar photovoltaics in water dams in the abovementioned hybrid energy plants in these two islands could generate significant amounts of solar electricity complementing the generated wind and hydro power. Use of floating solar photovoltaics in these two islands transform the co-generation energy plants to tri-generation plants producing hydro, wind and solar electricity
Design and Fabrication of an Electromechanical Tester to Perform Two-dimensional Tensile Testing for Flexible Materials
Get PDFThere are many diseases that affect the arteries, especially those related to their elasticity and stiffness, and they can be guessed by estimating and calculating the modulus of elasticity. Hence, the accurate calculation of the elastic modulus leads to an accurate assessment of these diseases, especially in their early stages, which can contribute to the treatment of these diseases early. Most of the calculations used the one-dimensional (1D) modulus of elasticity. From a mechanical point of view, the stresses to which the artery is subjected are not one-dimensional, but three-dimensional. Therefore, estimating at least a two-dimensional (2D) modulus of elasticity will necessarily be more accurate. To the knowledge of researchers, there is a lack of published research on this subject, as well as a paucity of research that designed and implemented a 2D tensile testing device (2DTTD). However, there is no inspection of arterial flexibility and elasticity using the 2DTTD adequately studied before. Therefore, the aim of this work is to design and implement the 2DTTD to scrutinize if there is a difference between the 1D and 2D tensile examination. Different sized rectangular silicone specimens were manually fabricated; they were tested individually using the fabricated 2DTTD, which mainly comprises four actuators synchronously working with the same velocity and axial load force, two at each axis. As expected using the 2DTTD, the dimensions of the specimen remarkably influence the tensile testing results; the strain and stress rates and the modulus of elasticity were influenced. To validate the acquired 2D tensile testing results, the 1D tensile testing was performed using the same fabricated 2DTTD and compared to results gained using another tensile testing apparatus. During the verification process, the input data for models calibration were sufficiently and accurately provided. The results showed reasonable precision and reliability in calculations of the 2D stress and strain rates during the whole deformation process. Each mechanical device that has been used has the possibility to stretch and squeeze the sample and log the change in the specimen elongation.
The authors thought that the present experimental methodology was applied to the linear mechanical device successfully, where the encoder that is attached to tested samples was in the principal direction. The present method is used to measure the deformation in a manner that differs from the traditional digital image correlation method, which required a toolset that is more expensive, where it incorporates high-accuracy optical equipment
Access Instruction to Digital Edge (AIDE): Technology Resources and Keying its Adoption to Teaching
Get PDFInstitution of learning encompassing pool of individuals, who are considered as spring of knowledge-the teachers; and knowledge catching vessel-the students, were the main respondents of the study. Frequencies, percentages, ranks and weighted means were used for the descriptive data, while the Pearson Product Moment Correlation was used to determine the significant relationship between the level of technology adoption of faculty and their profile variables and attitudes towards technology use in teaching. A total of two hundred sixty-six (266) faculty and three hundred ninety-five (395) students were involved. Findings revealed that the university invested huge amount for educational technology use, but there’s little of evidence in ICT adoption and use in instruction. ICT characteristics of faculty presented that there’s a need for them to be aware of their attitude toward ICT integration in their teaching because it is fundamental for it can make education logical, efficient, effective and interesting. Also, training on designing instructional material should be extended to them specifically workshops on word processing for their syllabi, assessment paper, reports, spreadsheet application, presentation design which is necessary during their research presentation, desktop publishing, internet technology, adobe photoshop and trouble shooting. For an avenue to effectively use technology in instruction daily activity of faculty, the university extension department in collaboration with the knowledge technology management should design then, a program that would assess the technology training needs of faculty to give way for the development of a regular training activity to non-IT faculty
Scope of Social Cognitive Theory and Research Designs in Student Motivation over the Past Twenty Years in Saudi Arabia: A Synthetic Literature Review
Get PDFA substantial body of research has raised concern over students’ lack of motivation in educational settings in the Middle East in general and more particularly in Saudi Arabia. This review utilized synthetic techniques to gather a methodical collection of existing research and emphasized two research questions: to what extent has Saudi students’ learning-related motivation been investigated? What factors affect learners’ motivation? To answer the questions, the included articles were classified based on fields of study, research methodologies, designs, and sample sizes. The included articles were then divided into categories dealing with motivation-related variables such learners’ self-efficacy beliefs, self-regulation, motivation, group work, and technologies. The findings suggest that despite the limited number of investigations, most motivation-related studies were conducted in the area of English as a second language and not in subjects such as sciences and technologies. Based on the types of data collection, generalizations of the findings from the published articles are deemed questionable. Furthermore, predictors of learners’ motivations were revealed, and limitations were discussed regarding the scope of research publications, methods, designs, and data collections. Directions for further investigations are presented
A New Variant of the ICP Algorithm for Pairwise 3D Point Cloud Registration
Get PDFPairwise 3D point cloud registration derived from Terrestrial Laser Scanner (TLS) in static mode is an essential task to produce locally consistent 3D point clouds. In this work, the contributions are twofold. First, a non-iterative scheme by merging the SIFT (Scale Invariant Feature Transform) 3D algorithm and the PFH (Point Feature Histograms) algorithm to find initial approximation of the transformation parameters is proposed. Then, a correspondence model based on a new variant of the ICP (Iterative Closest Point) algorithm to refine the transformation parameters is also proposed. To evaluate the local consistency of the pairwise 3D point cloud registration is used a point-to-distance approach. Experiments were performed using seven pairs of 3D point clouds into an urban area. The results obtained showed that the method achieves point-to-plane RMSE (Root of the Mean Square Error) mean values in the order of 2 centimeters
The Progress of Photothermal Effect Enhanced Electrocatalytic Oxygen Evolution Reaction
Get PDFHarnessing light energy is an important means to alleviate the energy crisis and reduce environmental pollution. Light irradiation nanostructures can produce electromagnetic field enhancement, generate hot carriers, induce resonant energy transfer and photothermal effects. For oxygen evolution reaction from water splitting, the photothermal effect can serve to promote electrocatalytic activity and also adjust the reaction pathway, thus improving performance
Eliminate Neck Spasm for Good, the Relationship between Neck Spasms Resulting from Daily Activities and the Exercises to Improve Neck Pain
Get PDFOur spine is like a bridge between our head and legs and they bear two thirds of our body weight. Our spine consists of 33 bones, called vertebras, including 23 moving vertebrae. Connective tissues, joints and discs connect these bones to each other. We also have strong muscles around the spine that enable movements and attach to each vertebra. A spasm is an involuntary tightening of muscle in your body. It often causes intense pain. This pain can last for minutes, hours, or days after the muscle relaxes and the spasm subsides. Spasms can happen in any part of your body where there’s muscle, including your neck. The ways for improving neck spasms are self-care treatments, alternative treatments and procedures, and Surgery.