Search results for: functional principal component analysis

Authors: Jamaludin Jamaludin, Suparji Suparji, Lilik Anifah, I. Gusti Putu Asto Buditjahjanto, Eppy Yundra

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Learning media is an important and main component in the learning process. By using currently available media, cadets still have difficulty understanding how the piston engine works, so they are not able to apply these concepts appropriately. This study aims to examine the development of interactive media for piston engine courses in order to improve student learning outcomes. The research method used is a literature study of several articles, journals and proceedings of interactive media development results from 2010-2020. The results showed that the development of interactive media is needed to support the learning process and influence the cognitive abilities of students. With this interactive media, learning outcomes can be improved and the learning process can be effective.

Keywords: interactive media, learning outcomes, learning process, literature study

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Authors: Shrikaant Kulkarni, Akshata Naik Nimbalkar

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In this worki a method protocol has been developed for the synthesis of innovative Co3O4 material by using a method of chemical synthesis followed by calcination. The effect of calcination temperature on the morphology, structure and catalytic performance on material in question is investigated by using characterization tools like scanning electron microscopy (SEM), X-ray diffraction (XRD) spectroscopy and electrochemical techniques. The SEM images reveal that the morphology of the Co3O4 material undergoes a change from the rod to a beadlike shape on calcination at temperature of 700 °C. The XRD image shows that although the morphology of synthesized Co3O4 material exhibits a cubic phase but it differs in crystallinity depending upon morphology. Similarly spherical beadlike Co3O4 material has exhibited better activity than its rodlike counterpart which is reflected from electrochemical findings. Further, its performance in terms of bifunctional nature and hlods a lot much of promise as a excellent electrode material in the next generation batteries and fuel cells.

Keywords: bifunctional, next generation material, Co3O4, XRD

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Authors: Raziyeh Mohammadi

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At present, nanoparticles are used for various biomedical applications where they facilitate laboratory diagnostics and therapeutics. The performance of nanoparticles for biomedical applications is often assessed by their narrow size distribution, suitable magnetic saturation, and low toxicity effects. Superparamagnetic iron oxide nanoparticles have received great attention due to their applications as contrast agents for magnetic resonance imaging (MRI. (Processes in the tissue where the blood brain barrier is intact in this way shielded from the contact to this conventional contrast agent and will only reveal changes in the tissue if it involves an alteration in the vasculature. This technique is very useful for detecting tumors and can even be used for detecting metabolic functional alterations in the brain, such as epileptic activity.SPIONs have found application in Magnetic Resonance Imaging (MRI) and magnetic hyperthermia. Unlike bulk iron, SPIONs do not have remnant magnetization in the absence of the external magnetic field; therefore, a precise remote control over their action is possible.

Keywords: nanoparticles, MRI, biomedical, iron oxide, spions

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Authors: Kadda Amara, Mohammed Elkeurti, Mostefa Zemouli, Yassine Benallou

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In this work, we present a study of the structural, elastic and electronic properties of the cubic antiperovskites XNMg3 (X=P, As, Sb and Bi) using the full-potential augmented plane wave plus local orbital (FP-LAPW+lo) within the Generalized Gradient Approximation based on PBEsol, Perdew 2008 functional. We determined the lattice parameters, the bulk modulus B and their pressure derivative B'. In addition, the elastic properties such as elastic constants (C11, C12 and C44), the shear modulus G, the Young modulus E, the Poisson's ratio ν and the B/G ratio are also given. For the band structure, density of states and charge density the exchange and correlation effects were treated by the Tran-Blaha modified Becke-Johnson potential to prevent the shortcoming of the underestimation of the energy gaps in both LDA and GGA approximations. The obtained results are compared to available experimental data and to other theoretical calculations.

Keywords: XNMg3 compounds, GGA-PBEsol, TB-mBJ, elastic properties, electronic properties

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Authors: Ricardo Paiva, Rui Soares, Felix Harnau, Bruno Fragoso

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Nickel-based alloys are materials well suited for service in extreme environments subjected to pressure and heat. Some industrial applications for Nickel-based alloys are aerospace and jet engines, oil and gas extraction, pollution control and waste processing, automotive and marine industry. It is generally recognized that grain refinement is an effective methodology to improve the quality of casted parts. Conventional grain refinement techniques involve the addition of inoculation substances, the control of solidification conditions, or thermomechanical treatment with recrystallization. However, such methods often lead to non-uniform grain size distribution and the formation of hard phases, which are detrimental to both wear performance and biocompatibility. Stirring of the melt by electromagnetic fields has been widely used in continuous castings with success for grain refinement, solute redistribution, and surface quality improvement. Despite the advantages, much attention has not been paid yet to the use of this approach on functional castings such as investment casting. Furthermore, the effect of electromagnetic stirring (EMS) fields on Nickel-based alloys is not known. In line with the gaps/needs of the state-of-art, the present research work targets to promote new advances in controlling grain size and morphology of investment cast Nickel based alloys. For such a purpose, a set of experimental tests was conducted. A high-frequency induction furnace with vacuum and controlled atmosphere was used to cast the Inconel 718 alloy in ceramic shells. A coil surrounded the casting chamber in order to induce electromagnetic stirring during solidification. Aiming to assess the effect of the electromagnetic stirring on Ni alloys, the samples were subjected to microstructural analysis and mechanical tests. The results show that electromagnetic stirring can be an effective methodology to modify the grain size and mechanical properties of investment-cast parts.

Keywords: investment casting, grain refinement, electromagnetic stirring, nickel alloys

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Authors: Ross Guest, Bjarne Jensen

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This paper analyses a potentially new consumption dividend from lower fertility arising from imperfect labour substitution by age. A smaller proportion of young workers relative to older workers raises relative youth wages given imperfect labour substitution by age. Discounted lifetime labour income rises which provides a consumption dividend. Simulation results are reported for the four Scandinavian countries, adopting a simple overlapping generations model. Imperfect labour substitution is modelled using a CRESH functional form of an aggregate labour index. The magnitudes of this new consumption dividend from a Low fertility projection compared with a high fertility projection are found to be approximately 4 percent annually, on average over the Scandinavian countries in the very long run, but somewhat lower in the short term. There is some sensitivity to the interest rate and the degree of consumption smoothing.

Keywords: fertility, consumption, productivity, labour substitution

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Authors: Vinod Kumar Gupta, Narendrakumar M. Chaudhari, Suchismitha Iskepalli, Chitra Dutta

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Background-The community composition of the human microbiome is known to vary at distinct anatomical niches. But little is known about the nature of variations if any, at the genome/sub-genome levels of a specific microbial community across different niches. The present report aims to explore, as a case study, the variations in gene repertoire of 28 Prevotella reference draft genomes derived from different body-sites of human, as reported earlier by the Human Microbiome Consortium. Results-The analysis reveals the exclusive presence of 11798, 3673, 3348 and 934 gene families and exclusive absence of 17, 221, 115 and 645 gene families in Prevotella genomes derived from the human oral cavity, gastro-intestinal tracts (GIT), urogenital tract (UGT) and skin, respectively. The pan-genome for Prevotella remains “open”. Distribution of various functional COG categories differs appreciably among the habitat-specific genes, within Prevotella pan-genome and between the GIT-derived Bacteroides and Prevotella. The skin and GIT isolates of Prevotella are enriched in singletons involved in Signal transduction mechanisms, while the UGT and oral isolates show higher representation of the Defense mechanisms category. No niche-specific variations could be observed in the distribution of KEGG pathways. Conclusion-Prevotella may have developed distinct genetic strategies for adaptation to different anatomical habitats through selective, niche-specific acquisition and elimination of suitable gene-families. In addition, individual microorganisms tend to develop their own distinctive adaptive stratagems through large repertoires of singletons. Such in situ, habitat-driven refurbishment of the genetic makeup can impart substantial intra-lineage genome diversity within the microbes without perturbing their general taxonomic heritage.

Keywords: body niche adaptation, human microbiome, pangenome, Prevotella

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Authors: Seung Cho Yang, Jae Sung Lee, Se Hee Park

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This study suggests the analysis method to predict the damages of tunnel concrete caused by fires. The result obtained from the analyses of concrete temperatures at a fire in a tunnel using ABAQUS was compared with the test result. After the reliability of the analysis method was verified, the temperatures of a tunnel at a real fire and those of concrete during the fire were estimated to predict fire damages. The temperatures inside the tunnel were estimated by FDS, a CFD model. It was deduced that the fire performance of tunnel lining and the fire damages of the structure at an actual fire could be estimated by the analysis method.

Keywords: fire resistance, heat transfer, numerical analysis, tunnel fire

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Authors: Ji Sun Kim, Jae Ho Baek, Kyeong Ho Kim, Ji Hae Ha, Seong Soo Hong, Jung-Wook Park, Man Sig Lee

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Carbon supported palladium catalysts have been used in many industrial reactions, especially for hydrogenation in the fine chemical industry. Porous carbons had been widely used as catalyst supports due to its higher surface area and larger pore volume. The specific surface area, pore structure and surface chemical functional groups of porous carbon affects metal dispersion and particle size. In this paper, we confirm the effect of support texture on the dispersion of Pd. Pd catalyst supported on activated carbon having various specific surface area were characterized by BET, XRD and FE-TEM. Catalyst activity and dispersion of prepared catalyst were evaluated on the basis of the CO adsorption capacity by CO-chemisorption. As concluding remark to this part of our study, let us note that specific area of carbon play important role on the synthesis of Pd/C catalyst/.

Keywords: carbon, dispersion, Pd/C, specific are, support

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Authors: Olga Kononova, Sergey Lyapin

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Global information society requirements are transparency and reliability of data, as well as ability to manage information resources independently; particularly to search, to analyze, to evaluate information, thereby obtaining new expertise. Moreover, it is satisfying the society information needs that increases the efficiency of the enterprise management and public administration. The study of structurally organized thematic and semantic contexts of different types, automatically extracted from unstructured data, is one of the important tasks for the application of information technologies in education, science, culture, governance and business. The objectives of this study are the contextual knowledge typologization, selection or creation of effective tools for extracting and analyzing contextual knowledge. Explication of various kinds and forms of the contextual knowledge involves the development and use full-text search information systems. For the implementation purposes, the authors use an e-library 'Humanitariana' services such as the contextual search, different types of queries (paragraph-oriented query, frequency-ranked query), automatic extraction of knowledge from the scientific texts. The multifunctional e-library «Humanitariana» is realized in the Internet-architecture in WWS-configuration (Web-browser / Web-server / SQL-server). Advantage of use 'Humanitariana' is in the possibility of combining the resources of several organizations. Scholars and research groups may work in a local network mode and in distributed IT environments with ability to appeal to resources of any participating organizations servers. Paper discusses some specific cases of the contextual knowledge explication with the use of the e-library services and focuses on possibilities of new types of the contextual knowledge. Experimental research base are science texts about 'e-government' and 'computer games'. An analysis of the subject-themed texts trends allowed to propose the content analysis methodology, that combines a full-text search with automatic construction of 'terminogramma' and expert analysis of the selected contexts. 'Terminogramma' is made out as a table that contains a column with a frequency-ranked list of words (nouns), as well as columns with an indication of the absolute frequency (number) and the relative frequency of occurrence of the word (in %% ppm). The analysis of 'e-government' materials showed, that the state takes a dominant position in the processes of the electronic interaction between the authorities and society in modern Russia. The media credited the main role in these processes to the government, which provided public services through specialized portals. Factor analysis revealed two factors statistically describing the used terms: human interaction (the user) and the state (government, processes organizer); interaction management (public officer, processes performer) and technology (infrastructure). Isolation of these factors will lead to changes in the model of electronic interaction between government and society. In this study, the dominant social problems and the prevalence of different categories of subjects of computer gaming in science papers from 2005 to 2015 were identified. Therefore, there is an evident identification of several types of contextual knowledge: micro context; macro context; dynamic context; thematic collection of queries (interactive contextual knowledge expanding a composition of e-library information resources); multimodal context (functional integration of iconographic and full-text resources through hybrid quasi-semantic algorithm of search). Further studies can be pursued both in terms of expanding the resource base on which they are held, and in terms of the development of appropriate tools.

Keywords: contextual knowledge, contextual search, e-library services, frequency-ranked query, paragraph-oriented query, technologies of the contextual knowledge extraction

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Authors: Karolína Vozková, Matěj Kuc

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This paper analyzes recent trends in cost efficiency of European cooperative banks using efficient frontier analysis. Our methodology is based on stochastic frontier analysis which is run on a set of 649 European cooperative banks using data between 2006 and 2015. Our results show that average inefficiency of European cooperative banks is increasing since 2008, smaller cooperative banks are significantly more efficient than the bigger ones over the whole time period and that share of net fee and commission income to total income surprisingly seems to have no impact on bank cost efficiency.

Keywords: cooperative banks, cost efficiency, efficient frontier analysis, stochastic frontier analysis, net fee and commission income

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Authors: Yasam Palguna, Rajesh Korla

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The efficiency of thermally operated systems can be improved by increasing the operating temperature, thereby decreasing the fuel consumption and carbon footprint. Hence, there is a continuous need for replacing the existing materials with new alloys with higher temperature working capabilities. During the last decade, multi principal element alloys, commonly known as high entropy alloys are getting more attention because of their superior high temperature strength along with good high temperature corrosion and oxidation resistance, The present work focused on the microstructure and high temperature tensile behavior of Al0.2CoCrFeNiMo0.5 high entropy alloy (HEA). Wrought Al0.2CoCrFeNiMo0.5 high entropy alloy, produced by vacuum induction melting followed by thermomechanical processing, is tested in the temperature range of 200 to 900oC. It is exhibiting very good resistance to softening with increasing temperature up to 700oC, and thereafter there is a rapid decrease in the strength, especially beyond 800oC, which may be due to simultaneous occurrence of recrystallization and precipitate coarsening. Further, it is exhibiting superplastic kind of behavior with a uniform elongation of ~ 275 % at 900 oC temperature and 1 x 10-3 s-1 strain rate, which may be due to the presence of fine stable equi-axed grains. Strain rate sensitivity of 0.3 was observed, suggesting that solute drag dislocation glide might be the active mechanism during superplastic kind of deformation. Post deformation microstructure suggesting that cavitation at the sigma phase-matrix interface is the failure mechanism during high temperature deformation. Finally, high temperature properties of the present alloy will be compared with the contemporary high temperature materials such as ferritic, austenitic steels, and superalloys.

Keywords: high entropy alloy, high temperature deformation, super plasticity, post-deformation microstructures

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Authors: M. Karzhauov, А. Mukhambetova, M. Sarsenova, E. Raimagambetov, V. Ogay

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Regeneration of injured articular cartilage remains one of the most difficult and unsolved problems in traumatology and orthopedics. Currently, for the treatment of cartilage defects surgical techniques for stimulation of the regeneration of cartilage in damaged joints such as multiple microperforation, mosaic chondroplasty, abrasion and microfractures is used. However, as shown by clinical practice, they can not provide a full and sustainable recovery of articular hyaline cartilage. In this regard, the current high hopes in the regeneration of cartilage defects reasonably are associated with the use of tissue engineering approaches to restore the structural and functional characteristics of damaged joints using stem cells, growth factors and biopolymers or scaffolds. The purpose of the present study was to investigate the effects of chondroinductive growth factors and synovium-derived mesenchymal stem cells (SD-MSCs) on the regeneration of cartilage defects in rabbits. SD-MSCs were isolated from the synovium membrane of Flemish giant rabbits, and expanded in complete culture medium α-MEM. Rabbit SD-MSCs were characterized by CFU-assay and by their ability to differentiate into osteoblasts, chondrocytes and adipocytes. The effects of growth factors (TGF-β1, BMP-2, BMP-4 and IGF-I) on MSC chondrogenesis were examined in micromass pellet cultures using histological and biochemical analysis. Articular cartilage defect (4mm in diameter) in the intercondylar groove of the patellofemoral joint was performed with a kit for the mosaic chondroplasty. The defect was made until subchondral bone plate. Delivery of SD-MSCs and growth factors was conducted in combination with hyaloronic acid (HA). SD-MSCs, growth factors and control groups were compared macroscopically and histologically at 10, 30, 60 and 90 days aftrer intra-articular injection. Our in vitro comparative study revealed that TGF-β1 and BMP-4 are key chondroinductive factors for both the growth and chondrogenesis of SD-MSCs. The highest effect on MSC chondrogenesis was observed with the synergistic interaction of TGF-β1 and BMP-4. In addition, biochemical analysis of the chondrogenic micromass pellets also revealed that the levels of glycosaminoglycans and DNA after combined treatment with TGF-β1 and BMP-4 was significantly higher in comparison to individual application of these factors. In vivo study showed that for complete regeneration of cartilage defects with intra-articular injection of SD-MSCs with HA takes time 90 days. However, single injection of SD-MSCs in combiantion with TGF-β1, BMP-4 and HA significantly promoted regeneration rate of the cartilage defects in rabbits. In this case, complete regeneration of cartilage defects was observed in 30 days after intra-articular injection. Thus, our in vitro and in vivo study demonstrated that combined application of rabbit SD-MSC with chondroinductive growth factors and HA results in strong synergistic effect on the chondrogenesis significantly enhancing regeneration of the damaged cartilage.

Keywords: Mesenchymal stem cells, synovium, chondroinductive factors, TGF-β1, BMP-2, BMP-4, IGF-I

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Authors: Daniel Fozer

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Limiting global warming to 1.5°C to the pre-industrial levels urges the application of efficient and sustainable carbon dioxide removal (CDR) technologies. Microalgae based biorefineries offer scalable solutions for the biofixation of CO2, where the produced biomass can be transformed into value added products by applying thermochemical processes. In this paper we report on the utilization of hydrochar as a blending component in hydrothermal gasification (HTG) process. The effects of blending ratio and hydrochar quality were investigated on the biogas yield and and composition. It is found that co-gasifying the hydrochar and the algae biomass can increase significantly the total gas yield and influence the biogas (H2, CH4, CO2, CO, C2H4, C2H6) composition. It is determined that the carbon conversion ratio, hydrogen and methane selectivity can be increased by influencing the fuel ratio of hydrochar via hydrothermal carbonization. In conclusion, it is found that increasing the synergy between hydrothermal technologies result in elevated conversion efficiency.

Keywords: biogas, CDR, Co-HTG, hydrochar, microalgae

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Authors: May Abdelghani

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The present work is devoted to the study of the microstructural anisotropy in mechanical cyclic behavior of the 2017AA aluminum alloy which is widely used in the aerospace industry. The main purpose of the study is to investigate the microstructural origins of this anisotropy already confirmed in our previous work in 2017AA aluminum alloy. To do this, we have used the microstructural analysis resources such as Scanning Electron Microscope (SEM) to see the differences between breaks from different directions of cyclic loading. Another resource of investigation was used in this study is that the EBSD method, which allows us to obtain a mapping of the crystallographic texture of our material. According to the obtained results in the microscopic analysis, we are able to identify the origins of the anisotropic behavior at the macroscopic scale.

Keywords: fatigue damage, cyclic behavior, anisotropy, microstructural analysis

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Authors: Surbhi Kaura, Sachin Kandhari, Shahiduz Zafar

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Chronic stroke, characterized by persistent motor deficits, often necessitates comprehensive rehabilitation interventions to improve functional outcomes and mitigate long-term dependency. Luna neurorobotic devices, integrated with EMG feedback systems, provide an innovative platform for facilitating neuroplasticity and functional improvement in stroke survivors. This retrospective study aims to investigate the impact of EMG-based Luna neurorobotic interventions on the strengthening of the affected side in chronic stroke patients. In rehabilitation, active patient participation significantly activates the sensorimotor network during motor control, unlike passive movement. Stroke is a debilitating condition that, when not effectively treated, can result in significant deficits and lifelong dependency. Common issues like neglecting the use of limbs can lead to weakness in chronic stroke cases. In rehabilitation, active patient participation significantly activates the sensorimotor network during motor control, unlike passive movement. This study aims to assess how electromyographic triggering (EMG-triggered) robotic treatments affect walking, ankle muscle force after an ischemic stroke, and the coactivation of agonist and antagonist muscles, which contributes to neuroplasticity with the assistance of biofeedback using robotics. Methods: The study utilized robotic techniques based on electromyography (EMG) for daily rehabilitation in long-term stroke patients, offering feedback and monitoring progress. Each patient received one session per day for two weeks, with the intervention group undergoing 45 minutes of robot-assisted training and exercise at the hospital, while the control group performed exercises at home. Eight participants with impaired motor function and gait after stroke were involved in the study. EMG-based biofeedback exercises were administered through the LUNA neuro-robotic machine, progressing from trigger and release mode to trigger and hold, and later transitioning to dynamic mode. Assessments were conducted at baseline and after two weeks, including the Timed Up and Go (TUG) test, a 10-meter walk test (10m), Berg Balance Scale (BBG), and gait parameters like cadence, step length, upper limb strength measured by EMG threshold in microvolts, and force in Newton meters. Results: The study utilized a scale to assess motor strength and balance, illustrating the benefits of EMG-biofeedback following LUNA robotic therapy. In the analysis of the left hemiparetic group, an increase in strength post-rehabilitation was observed. The pre-TUG mean value was 72.4, which decreased to 42.4 ± 0.03880133 seconds post-rehabilitation, with a significant difference indicated by a p-value below 0.05, reflecting a reduced task completion time. Similarly, in the force-based task, the pre-knee dynamic force in Newton meters was 18.2NM, which increased to 31.26NM during knee extension post-rehabilitation. The post-student t-test showed a p-value of 0.026, signifying a significant difference. This indicated an increase in the strength of knee extensor muscles after LUNA robotic rehabilitation. Lastly, at baseline, the EMG value for ankle dorsiflexion was 5.11 (µV), which increased to 43.4 ± 0.06 µV post-rehabilitation, signifying an increase in the threshold and the patient's ability to generate more motor units during left ankle dorsiflexion. Conclusion: This study aimed to evaluate the impact of EMG and dynamic force-based rehabilitation devices on walking and strength of the affected side in chronic stroke patients without nominal data comparisons among stroke patients. Additionally, it provides insights into the inclusion of EMG-triggered neurorehabilitation robots in the daily rehabilitation of patients.

Keywords: neurorehabilitation, robotic therapy, stroke, strength, paralysis

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Authors: Lingfeng Wang, Zhipeng Chen, Shuang Qiu, Shijian Ge

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The effects of wastewater, with four different nutrient loadings, from synthetic centrate on biomass production of Chlorella vulgaris, nutrient removal, microalgal settling, and lipid production were investigated in photobioreactors under both batches and, subsequently, semi-continuous operations. At higher centrate concentration factors (17.2% and 36.2%), hydraulic retention time and pH adjustments could be employed to sustain acceptable microalgal growth rates and wastewater treatment. Similar nutrient removals efficiencies (>95%) and biomass production (0.42-0.51 g/L) were observed for the four centrate concentrations. Both the lipid productivity and lipid content decreased with increasing nutrient loading in the wastewater. The results also demonstrated that the mass ratio of carbohydrate to protein could provide a good indication of microalgal settling performance, rather than sole component composition or total extracellular polymeric substances.

Keywords: lipid production, microalgae, nutrient removal, wastewater

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Authors: Nasser A. Al-Azri

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The effectiveness of passive cooling techniques is assessed based on bioclimatic charts that require the typical meteorological year (TMY) for a specified location for their development. However, TMYs are not always available; mainly due to the scarcity of records of solar radiation which is an essential component used in developing common TMYs intended for general uses. Since solar radiation is not required in the development of the bioclimatic chart, this work suggests developing TMYs based solely on the relevant parameters. This approach improves the accuracy of the developed TMY since only the relevant parameters are considered and it also makes the development of the TMY more accessible since solar radiation data are not used. The presented paper will also discuss the development of the TMY from the raw data available at the NOAA-NCDC archive of world weather data and the construction of the bioclimatic charts for some randomly selected locations around the world.

Keywords: bioclimatic charts, passive cooling, TMY, weather data

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Authors: Wei Jin

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Efficient and selective metal recovery from emerging solid waste, such as spent lithium batteries, electronic waste and SCR catalysts, is of great importance from both environmental and resource considerations. In order to overcome the bottlenecks of long flow-sheet and severe secondary pollution in conventional processes, the rational design of 2-electron oxygen reduction reaction (ORR) and capacitive deionization (CDI) nanomaterials were developed for the precise electrochemical metal recovery. It has been demonstrated that the modified carbon nanomaterials can be employed as 2e ORR to produce H2O2 in aqueous solution, in which the metal can be leached out from the solid waste as ions. Moreover, the multi-component metallic solution can be electrochemically extracted with good efficiency and selectivity with the nanoporous aerogel. Each system presents stable performance for long-term operation and can be used in industrial solid waste treatment. This study provides a materials-oriented, cleaner metal recovery approach for strategic metal resources sustainability.

Keywords: electrochemistry, metal recovery, waste steams, nanomaterials

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Authors: M. Sarai Atab, A. Smallbone, A. P. Roskilly

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A thermodynamic study is performed on the Reverse Osmosis (RO) desalination process for brackish water. The detailed RO model of thermodynamics properties with and without an energy recovery device was built in Simulink/MATLAB and validated against reported measurement data. The efficiency of desalination plants can be estimated by both the first and second laws of thermodynamics. While the first law focuses on the quantity of energy, the second law analysis (i.e. exergy analysis) introduces quality. This paper used the Main Outfall Drain in Iraq as a case study to conduct energy and exergy analysis of RO process. The result shows that it is feasible to use energy recovery method for reverse osmosis with salinity less than 15000 ppm as the exergy efficiency increases twice. Moreover, this analysis shows that the highest exergy destruction occurs in the rejected water and lowest occurs in the permeate flow rate accounting 37% for 4.3% respectively.

Keywords: brackish water, exergy, irrigation, reverse osmosis (RO)

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Authors: Dan Xie

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The use of discourse markers (DMs) can play a crucial role in representing discourse interaction and pragmatic competence. Learners’ use of DMs and differences between native speakers (NSs) and non-native speakers (NNSs) in the use of various DMs have been the focus of considerable research attention. However, some commonly used DMs, such as you know, have not received as much attention in comparative studies, especially in the Chinese context. This study analyses data in two corpora (COLSEC and Spoken BNC 2014 (14-25)) to investigate how Chinese learners differ from NNSs in their use of the DM you know and its functions in speech. The results show that there is a significant difference between the two corpora in terms of the frequency of use of you know. In terms of the functions of you know, the study shows that six functions can all be present in both corpora, although there are significant differences between the five functional dimensions, especially in introducing a claim linked to the prior discourse and highlighting particular points in the discourse. It is hoped to show empirically how Chinese learners and NSs use DMs differently.

Keywords: you know, discourse marker, native speaker, Chinese learner

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Authors: Anna Rhodora A. Solar, Jan Emil N. Langomez

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Social Media plays a crucial role in influencing Philippine public opinion with regard to a variety of socio-political issues. This became evident in the massacre of 44 members of the Special Action Force (SAF 44) tasked by the Philippine government to capture one of the US Federal Bureau of Investigation’s most wanted terrorists. The incident was said to be perpetrated by members of the Moro Islamic Liberation Front and the Bangsamoro Islamic Freedom Fighters. Part of the online discourse within Philippine cyberspace sparked intense debates on Filipino Muslim identity, with several Facebook viral posts linking Islam as a factor to the tragic event. Facebook is considered to be the most popular social media platform in the Philippines. As such, this begs the question of the extent to which social media, specifically Facebook, shape the perceptions of Filipinos on Filipino Muslims. This study utilizes Habermas’ theory of communicative action as it offers an explanation on how public sphere such as social media could be a network for communicating information and points of view through free and open dialogue among equal citizens to come to an understanding or common perception. However, the paper argues that communicative action which is aimed at reaching understanding free from force, and strategic action which is aimed at convincing someone through argumentation may not necessarily be mutually exclusive since reaching an understanding can also be considered as a result of convincing someone through argumentation. Moreover, actors may clash one another in their ideas before reaching common understanding, hence the presence of force. Utilizing content analysis on the Facebook posts with Islamic component that went viral after the massacre of the SAF 44, this paper argues that framing the image of Filipino Muslims through Facebook reflects both communicative and strategic actions. Moreover, comment threads on viral posts manifest force albeit implicit.

Keywords: communication, Muslim, Philippines, social media

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Authors: Zhenqiu Liu

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Visualizing the heterogeneity within cell-populations for single-cell RNA-seq data is crucial for studying the functional diversity of a cell. However, because of the high level of noises, outlier, and dropouts, it is very challenging to measure the cell-to-cell similarity (distance), visualize and cluster the data in a low-dimension. Minimum volume embedding (MVE) projects the data into a lower-dimensional space and is a promising tool for data visualization. However, it is computationally inefficient to solve a semi-definite programming (SDP) when the sample size is large. Therefore, it is not applicable to single-cell RNA-seq data with thousands of samples. In this paper, we develop an efficient algorithm with an accelerated proximal gradient method and visualize the single-cell RNA-seq data efficiently. We demonstrate that the proposed approach separates known subpopulations more accurately in single-cell data sets than other existing dimension reduction methods.

Keywords: single-cell RNA-seq, minimum volume embedding, visualization, accelerated proximal gradient method

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Authors: Ben Nadler

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Cell adhesion plays a vital role in many cell activities. The motivation to model cell adhesion is to study important biological processes, such as cell spreading, cell aggregation, tissue formation, and cell adhesion, which are very challenging to study by experimental methods alone. This study provides important insight into cell adhesion, which can lead to improve regenerative medicine and tissue formation techniques. In this presentation the biological cells adhesion is mediated by receptors–ligands binding and the diffusivity of the receptor on the cell membrane surface. The ability of receptors to diffuse on the cell membrane surface yields a very unique and complicated adhesion mechanism, which is exclusive to cells. The phospholipid bilayer, which is the main component in the cell membrane, shows fluid-like behavior associated with the molecules’ diffusivity. The biological cell is modeled as a fluid-like membrane with negligible bending stiffness enclosing the cytoplasm fluid. The in-plane mechanical behavior of the cell membrane is assumed to depend only on the area change, which is motivated by the fluidity of the phospholipid bilayer. In addition, the presence of receptors influences on the local mechanical properties of the cell membrane is accounted for by including stress-free area change, which depends on the receptor density. Based on the physical properties of the receptors and ligands the attraction between the receptors and ligands is modeled as a charged-nonpolar which is a noncovalent interaction. Such interaction is a short-range type, which decays fast with distance. The mobility of the receptor on the cell membrane is modeled using the diffusion equation and Fick’s law is used to model the receptor–receptor interactions. The resultant interaction force, which includes receptor–ligand and receptor–receptor interaction, is decomposed into tangential part, which governs the receptor diffusion, and normal part, which governs the cell deformation and adhesion. The formulation of the governing equations and numerical simulations will be presented. Analysis of the adhesion characteristic and properties are discussed. The roles of various thermomechanical properties of the cell, receptors and ligands on the cell adhesion are investigated.

Keywords: cell adhesion, cell membrane, receptor-ligand interaction, receptor diffusion

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Authors: Shishen Xie, Yingda L. Xie

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Tuberculosis (TB) is a potentially serious infectious disease that remains a health concern. The Interferon Gamma Release Assay (IGRA) is a blood test to find out if an individual is tuberculous positive or negative. This study applies statistical analysis to the clinical data of interferon-gamma levels of seventy-three subjects who diagnosed pulmonary TB in an anti-tuberculous treatment. Data analysis is performed to determine if there is a significant decline in interferon-gamma levels for the subjects during a period of six months, and to infer if the anti-tuberculous treatment is effective.

Keywords: data analysis, interferon gamma release assay, statistical methods, tuberculosis infection

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Authors: Asmaa M. Hussein, Amr Wassal, Ahmed Farouk Al-Sadek, A. F. Abd El-Rahman

Abstract:

In this study, a multivariate analysis of potato spectroscopic data was presented to detect the presence of brown rot disease or not. Near-Infrared (NIR) spectroscopy (1,350-2,500 nm) combined with multivariate analysis was used as a rapid, non-destructive technique for the detection of brown rot disease in potatoes. Spectral measurements were performed in 565 samples, which were chosen randomly at the infection place in the potato slice. In this study, 254 infected and 311 uninfected (brown rot-free) samples were analyzed using different advanced statistical analysis techniques. The discrimination performance of different multivariate analysis techniques, including classification, pre-processing, and dimension reduction, were compared. Applying a random forest algorithm classifier with different pre-processing techniques to raw spectra had the best performance as the total classification accuracy of 98.7% was achieved in discriminating infected potatoes from control.

Keywords: Brown rot disease, NIR spectroscopy, potato, random forest

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Authors: Ram Bikram Thapa, Ganesh Lama

Abstract:

The Micro Hydro is one of the successful technology in Rural Nepal. Kavre is one of the pioneer district of sustainability of Micro Hydro Projects. A total of 30 Micro Hydro projects have been constructed with producing 700 KW of energy in northern side of the Kavre district. This study shows that 67% of projects have been affected by devastating earthquake in April and May, 2015. Out of them 23% are completely damaged. Most of the structures are failure like Penstock 71%, forebay 21%, powerhouse 7% have been completely damaged and 91% Canal & 44% Intake structures have been partially damaged by the earthquake. This paper empathizes that the engineering design is the vital component for sustainability of Micro Hydro Projects. This paper recommended that technicians should be considered the safety factor of earthquake and provision of disaster recovery fund during design of Micro Hydro Projects.

Keywords: micro hydro, earthquake, structural failure, sustainability

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Authors: Daniel Thompson, Muhammad Peerbux, Sophie Cerutti, Hansraj Bookun

Abstract:

Introduction: Dialysis access is a key component of the care of patients with end stage renal failure. In our institution, a combined service of vascular surgeons and nephrologists are responsible for the creation and maintenance of arteriovenous fisultas (AVF), tenckhoff cathethers and Hickman/permcath lines. This poster investigates the last 10 years of dialysis access surgery conducted at St. Vincent’s Hospital Melbourne. Method: A cross-sectional retrospective analysis was conducted of patients of St. Vincent’s Hospital Melbourne (Victoria, Australia) utilising data collection from the Australasian Vascular Audit (Australian and New Zealand Society for Vascular Surgery). Descriptive demographic analysis was carried out as well as operation type, length of hospital stays, postoperative deaths and need for reoperation. Results: 2085 patients with renal failure were operated on between the years of 2011 and 2020. 1315 were male (63.1%) and 770 were female (36.9%). The mean age was 58 (SD 13.8). 92% of patients scored three or greater on the American Society of Anesthiologiests classification system. Almost half had a history of ischaemic heart disease (48.4%), more than half had a history of diabetes (64%), and a majority had hypertension (88.4%). 1784 patients had a creatinine over 150mmol/L (85.6%), the rest were on dialysis (14.4%). The most common access procedure was AVF creation, with 474 autologous AVFs and 64 prosthetic AVFs. There were 263 Tenckhoff insertions. We performed 160 cadeveric renal transplants. The most common location for AVF formation was brachiocephalic (43.88%) followed by radiocephalic (36.7%) and brachiobasilic (16.67%). Fistulas that required re-intervention were most commonly angioplastied (n=163), followed by thrombectomy (n=136). There were 107 local fistula repairs. Average length of stay was 7.6 days, (SD 12). There were 106 unplanned returns to theatre, most commonly for fistula creation, insertion of tenckhoff or permacath removal (71.7%). There were 8 deaths in the immediately postoperative period. Discussion: Access to dialysis is vital for patients with end stage kidney disease, and requires a multidisciplinary approach from both nephrologists, vascular surgeons, and allied health practitioners. Our service provides a variety of dialysis access methods, predominately fistula creation and tenckhoff insertion. Patients with renal failure are heavily comorbid, and prolonged hospital admission following surgery is a source of significant healthcare expenditure. AVFs require careful monitoring and maintenance for ongoing utility, and our data reflects a multitude of operations required to maintain usable access. The requirement for dialysis is growing worldwide and our data demonstrates a local experience in access, with preferred methods, common complications and the associated surgical interventions.

Keywords: dialysis, fistula, nephrology, vascular surgery

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Authors: Eric Chabrol, Sidonia B.G. Eckle, Renate de Boer, James McCluskey, Jamie Rossjohn, Mirjam H.M. Heemskerk, Stephanie Gras

Abstract:

αβ and γδ T-cells are disparate T-cell lineages that, via their use of either αβ or γδ T-cell antigen receptors (TCRs) respectively, can respond to distinct antigens. Here we characterise a new population of human T-cells, term δβ T-cells, that express TCRs comprising a TCR-δ variable gene fused to a Joining-α/Constant-α domain, paired with an array of TCR-β chains. We characterised the cellular, functional, biophysical and structural characteristic feature of this new T-cells population that reveal some new insight into TCR diversity. We provide molecular bases of how δβ T-cells can recognise viral peptide presented by Human Leukocyte Antigen (HLA) molecule. Our findings highlight how components from αβ and γδTCR gene loci can recombine to confer antigen specificity thus expanding our understanding of T-cell biology and TCR diversity.

Keywords: new delta-beta TCR, HLA, viral peptide, structural immunology

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Authors: Faran Chaudhry, Anser Daud, Doris Braunstein, Oleg Safir, Allan Gross, Paul Kuzyk

Abstract:

Background: Acetabular reconstruction in the context of massive acetabular bone loss is challenging. In rare scenarios where the extent of bone loss precludes shell placement (cup-cage), reconstruction at our center consisted of a cage combined with highly porous metal augments. This study evaluates survivorship, complications, and functional outcomes using this technique. Methods: A total of 131 cup-cage implants (129 patients) were included in our retrospective review of revisions of total hip arthroplasty from January 2003 to January 2022. Among these cases, 100/131 (76.3%) were women, the mean age at surgery time was 68.7 years (range, 29.0 to 92.0; SD, 12.4), and the mean follow-up was 7.7 years (range, 0.02 to 20.3; SD, 5.1). Kaplan-Meier survivorship analysis was conducted with failure defined as revision surgery and/or failure of the cup-cage reconstruction. Results: A total of 30 implants (23%) reached the study endpoint involving all-cause revision. Overall survivorship was 74.8% at 10 years and 69.8% at 15 years. Reasons for revision included infection 12/131 (9.1%), dislocation 10/131 (7.6%), aseptic loosening of cup and/or cage 5/131 (3.8%), and aseptic loosening of the femoral stem 2/131 (1.5%). The mean LLD improved from 12.2 ± 15.9 mm to 3.9 ± 11.8 (p<0.05). The horizontal and vertical hip centres on plain film radiographs were significantly improved (p<0.05). Functionally, there was a decrease in the number of patients requiring the use of gait aids, with fewer patients (34, 25.9%) using a cane, walker, or wheelchair post-operatively compared to pre-operatively (58, 44%). There was a significant increase in the number of independent ambulators from 24 to 47 (36%). Conclusion: The cup-cage construct is a reliable treatment option for the treatment of various acetabular defects. There are favourable survivorship, clinical and radiographic outcomes, with a satisfactory complication rate.

Keywords: revision total hip arthroplasty, acetabular defect, pelvic discontinuity, trabecular metal augment, cup-cage

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