Search results for: single and divided core perforated

Authors: Haseen Siddiqui, Sanjay M. Mahajani

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Various important reactions in chemical and metallurgical industries fall in the category of gas-solid reactions. These reactions can be categorized as catalytic and non-catalytic gas-solid reactions. In gas-solid reaction systems, heat and mass transfer limitations put an appreciable influence on the rate of the reaction. The consequences can be unavoidable for overlooking such effects while collecting the reaction rate data for the design of the reactor. Pyrolysis reaction comes in this category that involves the production of gases due to the interaction of heat and solid substance. Pyrolysis is also an important step in the gasification process and therefore, the gasification reactivity majorly influenced by the pyrolysis process that produces the char, as a feed for the gasification process. Therefore, in the present study, a non-isothermal transient 1-D model is developed for a single biomass pellet to investigate the effect of heat and mass transfer limitations on the rate of pyrolysis reaction. The obtained set of partial differential equations are firstly discretized using the concept of ‘method of lines’ to obtain a set of ordinary differential equation with respect to time. These equations are solved, then, using MATLAB ode solver ode15s. The model is capable of incorporating structural changes, porosity variation, variation in various thermal properties and various pellet shapes. The model is used to analyze the effectiveness factor for different values of Lewis number and heat of reaction (G factor). Lewis number includes the effect of thermal conductivity of the solid pellet. Higher the Lewis number, the higher will be the thermal conductivity of the solid. The effectiveness factor was found to be decreasing with decreasing Lewis number due to the fact that smaller Lewis numbers retard the rate of heat transfer inside the pellet owing to a lower rate of pyrolysis reaction. G factor includes the effect of the heat of reaction. Since the pyrolysis reaction is endothermic in nature, the G factor takes negative values. The more the negative value higher will be endothermic nature of the pyrolysis reaction. The effectiveness factor was found to be decreasing with more negative values of the G factor. This behavior can be attributed to the fact that more negative value of G factor would result in more energy consumption by the reaction owing to a larger temperature gradient inside the pellet. Further, the analytical expressions are also derived for gas and solid concentrations and effectiveness factor for two limiting cases of the general model developed. The two limiting cases of the model are categorized as the homogeneous model and unreacted shrinking core model.

Keywords: effectiveness factor, G-factor, homogeneous model, lewis number, non-catalytic, shrinking core model

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Authors: Robyn White, Juan Bornman, Ensa Johnson

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People with disabilities are at a high risk of becoming victims of crime. Individuals with little or no functional speech (LNFS) face an even higher risk. One way of reducing the risk of remaining a victim of crime is to face the alleged perpetrator in court as a witness – therefore it is important for a person with LNFS who has been a victim of crime to have the required vocabulary to testify in court. The aim of this study was to identify and describe the core and fringe legal vocabulary required by illiterate victims of crime, who have little or no functional speech, to testify in court as witnesses. A mixed-method, the exploratory sequential design consisting of two distinct phases was used to address the aim of the research. The first phase was of a qualitative nature and included two different data sources, namely in-depth semi-structured interviews and focus group discussions. The overall aim of this phase was to identify and describe core and fringe legal vocabulary and to develop a measurement instrument based on these results. Results from Phase 1 were used in Phase 2, the quantitative phase, during which the measurement instrument (a custom-designed questionnaire) was socially validated. The results produced six distinct vocabulary categories that represent the legal core vocabulary and 99 words that represent the legal fringe vocabulary. The findings suggested that communication boards should be individualised to the individual and the specific crime. It is believed that the vocabulary lists developed in this study act as a valid and reliable springboard from which communication boards can be developed. Recommendations were therefore made to develop an Alternative and Augmentative Communication Resource Tool Kit to assist the legal justice system.

Keywords: augmentative and alternative communication, person with little or no functional speech, sexual crimes, testifying in court, victim of crime, witness competency

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Authors: Haleh Dadgostar, Faramarz Akbari, Hosien Vahid Tari, Masoud Solaymani-Dodaran, Mohammad Razi

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Introduction: There are a number of exercises-protocols have been applied to improve low back pain. We compared the effect of supervised exercise therapy and home-based exercise therapy among patients with nonspecific chronic low back pain. Methods: 70 patients with nonspecific chronic low back pain were randomly (using a random number generator, excel) divided into two groups to compare the effects of two types of exercise therapy. After a common educational session to learn how to live with low back pain as well as to use core training protocols to strengthen the muscles, the subjects were randomly assigned to follow supervised exercise therapy (n = 31) or home-based exercise therapy (n = 34) for 20 weeks. Results: Although both types of exercise programs resulted in reduced pain, this factor decreased more significantly in supervised exercise program. All scores of fitness improved significantly in supervised exercise group. But only knee extensor strength score was increased in the home base exercise group. Conclusion: Comparing between two types of exercise, supervised group exercise showed more effective than the other one. Reduction in low back pain severity and improvement in muscle flexibility and strength can be more achieved by using a 20-week supervised exercise program compared to the home-based exercise program in patients with nonspecific chronic low back pain.

Keywords: low back pain, anthropometric parameters, supervised exercise therapy, home-based exercise therapy

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Authors: Ahmed Shariful Alam, Abu Hena M. Mustafa Kamal, M. Abdul Rahman, M. Nasmus Sakib Khan Shabbir, Atiqul Islam

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According to the rules of quantum mechanics there is a non-vanishing probability of for an electron to tunnel through a thin insulating barrier or a thin capacitor which is not possible according to the laws of classical physics. Tunneling of electron through a thin insulating barrier or tunnel junction is a random event and the magnitude of current flowing due to the tunneling of electron is very low. As the current flowing through a Single Electron Transistor (SET) is the result of electron tunneling through tunnel junctions of its source and drain the supply voltage requirement is also very low. As a result, the power consumption across a Single Electron Transistor is ultra-low in comparison to that of a MOSFET. In this paper simulations have been done with PSPICE for an inverter built with both SETs and MOSFETs. 35mV supply voltage was used for a SET built inverter circuit and the supply voltage used for a CMOS inverter was 3.5V.

Keywords: ITRS, enhancement type MOSFET, island, DC analysis, transient analysis, power consumption, background charge co-tunneling

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Authors: Alireza Pouladkhan, Mohammad Yavari Foroushani, Ali Mortazavi

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This paper presents a finite element model for a sandwich plate containing a piezoelectric core. A sandwich plate with a piezoelectric core is constructed using the shear mode of piezoelectric materials. The orientation of poling vector has a significant effect on deflection and stress induced in the piezo-actuated adaptive sandwich plate. In the present study, the influence of this factor for a clamped-clamped-free-free and simple-simple-free-free square sandwich plate is investigated using Finite Element Method. The study uses ABAQUS (v.6.7) software to derive the finite element model of the sandwich plate. By using this model, the study gives the influences of the poling vector angle on the response of the smart structure and determines the maximum transverse displacement and maximum stress induced.

Keywords: finite element method, sandwich plate, poling vector, piezoelectric materials, smart structure, electric enthalpy

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Authors: Francis Wargirai

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Since gaining independence in 1975, Papua New Guinea`s core challenge has been the consolidation of democracy against a backdrop of enormous social, political and territorial diversity. Consequently, the government has implemented several political reforms including decentralization. Constitutional planners believed that national unity, would be better achieved by sharing state power over centralization. They anticipated that this would institutionalize a democratic civic culture by providing opportunities to groups and individuals to make political decisions within their jurisdiction. This would then eventually lead to confidence and participation in the larger entity of the state. In retrospect, civil society and community based groups are largely underrated and have had minimal influence on decisions at the local level, consequently contributing to nepotism, patronism and cynicism. By applying an elitist approach to analyze how national political leaders exert their influence and power within the local government system and local communities, this paper argues that decentralization has fragmented local communities. With an absence of political party roots and deeply divided ethnic groups, national political leaders have used divide and rule tactics resulting in mistrust among citizens. Through their influence and power within local governments to dictate projects and services to certain areas, this has resulted in skepticism and divisions among civil society along different cultural cleavages. This has been a contributing factor to anomalies in democratic consolidation and democratic political culture in Papua New Guinea.

Keywords: civic culture, cultural cleavages, decentralization, democratic consolidation

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Authors: Ali A. Al-Jazaairry, Tahsin T. Sabbagh

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The stability of a single model pile located adjacent to a continuous cavity was studied. This paper is an attempt to understand the behaviour of axially loaded single pile embedded in clayey soil with the presences of cavities. The performance of piles located in such soils was studied analytically. A verification analysis was carried out on available studies to assess the ability of analytical model to correctly interpret the system behaviour. The study was adopted by finite element program (PLAXIS). The study included many cases; in each case, there is a critical value in which the presence of cavities has shown minimum effect on the pile performance. Figures including the load carrying capacity of pile with the affecting factors are presented. These figures provide beneficial information for pile design constructed close to underground cavities. It was concluded that the load carrying capacity of the pile is reduced by the presence of the cavity within the soil mass. This reduction varies according to the size and location of cavity.

Keywords: axial load, cavity, clay, pile, ultimate capacity

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Authors: Kishor C. Poria, Deepak Adroja, Arvind Bajaj

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During the last few decades, the growth of single crystals has attained enormous importance for both academic research and technology. Single crystals are pillars of modern technology. In recent emerging trends of photonics and optoelectronics technology, there has been increased need for organic and semi organic materials for Non-Linear Optical (NLO) applications. The paper dealt with the initiation of good single crystals of thiourea and metal doped thiourea. The authors have successfully grown thiourea (pure) and metal doped thiourea crystals using relatively simple and inexpensive slow evaporation of aqueous solution technique. Pure thiourea crystals were grown with different light intensities and frequencies as there growth conditions. Metals (Cu, Co, Ni, Fe) doped crystals were grown using a simple evaporation technique. The paper explains growth methods and associated grown parameters in detail. The average size of the crystal is varied in size from 40 mm x 1mm to 1.5 mm x 1.5 mm to 0.5 mm. Crystals obtained are hexagonal, tetragonal, and rectangular in shape with different optical qualities. All grown crystals are characterized using X-Ray Diffraction Analysis (XRD), Ultra Violet Visible analysis, and Fourier Transform Infrared Spectrometry. Their non-linear optical characteristics were determined by Second Harmonic Generation (SHG) and their Laser Dispersive analysis. The grown crystals are characterized using Nd:YAG laser and the highest conversion efficiency of the signal pass light are calculated. It shows 58 % of standard values for KDP crystals. All results are summarized in this work.

Keywords: crystal, metal-doped thiourea, non-linear optical, NLO, thiourea

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Authors: Li Yuan

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Objective: The combination of group psychology and Sertraline was used to explore the impact on the mental health status of adolescent patients with first-episode depression. Methods: A total of 118 adolescent depressed patients admitted to Yan'an University Hospital from October 2023 to August 2024 were divided into control group and observation group by random single blind method with 59 patients in each group. The two groups were treated with Sertraline, the control group received usual care, and the observation group used the usual care. The scores of mental health status and sleep quality index were compared between the two groups. Results: In intra-group comparison, the mental health status and sleep quality of the observation and control groups were better than the pre-intervention scores, and the difference was statistically significant (P <0.05). Post-intervention comparison: HAMA and HAMD scores were (12.36 ± 2.13) and (11.78 ± 2.02), significantly lower than (16.52 ± 2.09) and (15.79 ± 2.46), respectively (all P <0.05); PSQI score was (7.66 ± 1.05) and significantly lower (9.88 ± 3.01), with statistically significant difference (P <0.05). Conclusion: Self-regulation can improve their mental health and sleep quality.

Keywords: group psychotherapy, Sertraline, adolescent, depression, mental health status

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Authors: Noushin Shokouhinejad, Hasan Razmi, Reza Fekrazad, Saeed Asgary, Ammar Neshati, Hadi Assadian, Sanam Kheirieh

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This study compared the push-out bond strength of mineral trioxide aggregate (MTA) and a new endodontic cement (NEC) as root-end filling materials in root-end cavities prepared by ultrasonic technique (US) or Er,Cr:YSGG laser (L). Eighty single-rooted extracted human teeth were endodontically treated, apicectomised and randomly divided into four following groups (n = 20): US/MTA, US/NEC, L/MTA and L/NEC. In US/MTA and US/NEC groups, rooted cavities were prepared with ultrasonic retrotip and filled with MTA and NEC, respectively. In L/MTA and L/NEC groups, root-end cavities were prepared using Er, Cr:YSGG laser and filled with MTA and NEC, respectively. Each root was cut apically to create a 2 mm-thick root slice for measurement of bond strength using a universal testing machine. Then, all slices were examined to determine the mode of bond failure. Data were analysed using two-way ANOVA. Root-end filling materials showed significantly higher bond strength in root-end cavities prepared using the ultrasonic technique (US/MTA and US/NEC) (P < 0.001). The bond strengths of MTA and NEC did not differ significantly. The failure modes were mainly adhesive for MTA, but cohesive for NEC. In conclusion, bond strengths of MTA and NEC to root-end cavities were comparable and higher in ultrasonically prepared cavities.

Keywords: bond strength, Er, Cr:YSGG laser, MTA, NEC, root-end cavity

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Authors: S. Yousefi Oderji, B. Chen

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According to the ASTM C1018 toughness index method, the single and combined toughness effects of copper coated steel fiber and polypropylene (pp) fiber on reactive powder concrete (RPC) were investigated. Through flexural toughness test of RPC with different fiber volume dosages, the corresponding load-deflection curves were also drawn. Test results indicate that the binary combination of fibers provide the best flexural toughness, and improve the post-peak load-deflection characteristics of RPC. However, the single effect of pp fibers was not pronounced on improving the flexural toughness of RPC.

Keywords: RPC, PP, flexural toughness, toughness index

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Authors: Hamzeh Mazaherylaghab, Mehrangiz Vahabian, Seyyedeh Zahra Asghari

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The present study initially focused on the frequency of phrasal verbs used by Iranian learners of English. The results then needed to be compared to the findings from native speaker corpora. After the extraction of phrasal verbs from learner and native-speaker corpora the findings were analysed. The results showed that Iranian learners avoided using phrasal verbs in many cases. Some of the findings proved to be significant. It was also found that the learners used the single-word counterparts of the avoided phrasal verbs to compensate for their lack of knowledge in many cases. Semantic complexity and Lack of L1 counterpart may have been the main reasons for avoidance, but despite the avoidance phenomenon, the learners displayed a tendency to use many other phrasal verbs which may have been due to the increase in the number of multi-word verbs in Persian. The overall scores confirmed the fact that the language produced by the learners illustrates signs of more formal style in comparison with the native speakers of English by using less phrasal verbs and more formal single word verbs instead.

Keywords: corpus, corpora, LOCNESS, phrasal verbs, single-word verb

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Authors: Elaheh Hosseini, Otmar Bock, Monika Thomas

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The purpose of the present study was to determine the effect of climbing therapy on the components of attention of children with attention-deficit hyperactivity disorder (ADHD). Forty children with ADHD were assigned to either an intervention group or a control group. The exercise group participated in a climbing therapy program for ten weeks, whereas no intervention was administered to the control group. All two groups were then assessed with the same battery of attention tests used in our earlier study. We found that compared to the ‘intervention’ group, performance was higher in the ‘control’ group on tests of sustained, divided and distributed attention, on all four tests. The intervention group showed a significant improvement in components of attention after ten weeks. From this we conclude that climbing therapy can improve the attention of children with ADHD and can be considered as a promising intervention and a standalone treatment for children with ADHD.

Keywords: ADHD, climbing therapy, distributed attention, divided attention, selective attention, sustained attention

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Authors: Hossein Shokouhmand, Seyyed Mostafa Saadat

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In this paper, the effect of thermal dispersion on the performance of plate heat exchangers (PHEs) with sinusoidal plates is investigated. In this regard, the PHE is considered as a porous medium. The important property of a porous medium is porosity that is defined as the total fluid volume divided by the total volume occupied by the solid and fluid. A 2D array of parallel sinusoidal plates with laminar periodically developed forced convection and single-phase constant property flows and conduction in a homogenous solid phase in two directions is considered. The array of flows is counter and the flows heat capacities are equal. Numerical study of conjugate heat transfer and axial conduction in the solid phase with different plate thicknesses showed that there is an optimal porosity in which the efficiency of heat transfer is up to 4% more than the time when the porosity is near one. It is shown that the optimal porosity at zero angle of inclination depends both on Reynolds number and the aspect ratio. The optimal porosity increased while either the Reynolds number or waviness of plates increased.

Keywords: plate heat exchanger, optimal porosity, efficiency, aspect ratio

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Authors: Somaya A. Abd El Mottaleb, Ahmed Abd El Aziz, Heba A. Fayed, Moustafa H. Aly

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In this paper, we present the performance of spectral amplitude coding optical code division multiple access using different detectors at different transmission distances using single photodiode detection technique. Modified double weight codes are used as signature codes. Simulation results show that the system using avalanche photo detector can move distance longer than that using positive intrinsic negative photo detector.

Keywords: avalanche photodiode, modified double weight, multiple access technique, single photodiode.

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Authors: Hamza Javar Magnier, Robin Curtis

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There have been rapid advances in the upstream processing of protein therapeutics, which has shifted the bottleneck to downstream purification and formulation. Finding liquid formulations with shelf lives of up to two years is increasingly difficult for some of the newer therapeutics, which have been engineered for activity, but their formulations are often viscous, can phase separate, and have a high propensity for irreversible aggregation1. We explore means to develop improved predictive ability from a better understanding of how protein-protein interactions on formulation conditions (pH, ionic strength, buffer type, presence of excipients) and how these impact upon the initial steps in protein self-association and aggregation. In this work, we study the initial steps in the aggregation pathways using a minimal protein model based on square-well potentials and discontinuous molecular dynamics. The effect of model parameters, including range of interaction, stiffness, chain length, and chain sequence, implies that protein models fold according to various pathways. By reducing the range of interactions, the folding- and collapse- transition come together, and follow a single-step folding pathway from the denatured to the native state2. After parameterizing the model interaction-parameters, we developed an understanding of low-temperature conformational properties and fluctuations, and the correlation to the folding transition of proteins in isolation. The model fluctuations increase with temperature. We observe a low-temperature point, below which large fluctuations are frozen out. This implies that fluctuations at low-temperature can be correlated to the folding transition at the melting temperature. Because proteins “breath” at low temperatures, defining a native-state as a single structure with conserved contacts and a fixed three-dimensional structure is misleading. Rather, we introduce a new definition of a native-state ensemble based on our understanding of the core conservation, which takes into account the native fluctuations at low temperatures. This approach permits the study of a large range of length and time scales needed to link the molecular interactions to the macroscopically observed behaviour. In addition, these models studied are parameterized by fitting to experimentally observed protein-protein interactions characterized in terms of osmotic second virial coefficients.

Keywords: protein folding, native-ensemble, conformational fluctuation, aggregation

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Authors: G. Blanco-Lizana, C. García-Fernández, J. A. Sánchez

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Growth is a productive trait regulated by a large and complex gene network with very different effect. Some of they (candidate genes) have a higher effect and are excellent resources to search in them polymorphisms correlated with differences in growth rates. This study was focused on the identification of single nucleotide polymorphism (SNP) in MyoD-1 and MyoD-2 genes, members of the family of myogenic regulatory genes with a key role in the differentiation and development of muscular tissue.(MFRs), and its evaluation as potential markers in genetic selection programs for growth in gilthead sea bream (Sparus aurata). Through a sequencing in 30 seabream (classified as unrelated by microsatellite markers) of 1.968bp in MyoD-1 gene [AF478568 .1] and 1.963bp in MyoD-2 gene [AF478569.1], three SNPs were identified in each gene (SaMyoD-1 D2100A (D indicate a deletion) SaMyoD-1 A2143G and SaMyoD-1 A2404G and SaMyoD-2_A785C, SaMyoD-2_C1982T and SaMyoD-2_A2031T). The relationships between SNPs and body weight were evaluated by SNP genotyping of 53 breeders from two broodstocks (A:18♀-9♂; B:16♀-10♂) and 389 offspring divided into two groups (slow- and fast-growth) with significant differences in growth at 18 months of development (A18Slow: N=107, A18Fast: N=103, B18Slow: N=92 and B18Fast: N=87) (Borrell et al., 2011). Haplotype and diplotype were reconstructed from genotype data by Phase 2.1 software. Differences among means of different diplotypes were calculated by one-way ANOVA followed by post-hoc Tukey test. Association analysis indicated that single SNP did not show significant effect on body weight. However, when the analysis is carried out considering haplotype data it was observed that the DGG haplotipe of MyoD-1 gen and CCA haplotipe of MyoD- 2gen were associated to with lower body weight. This haplotype combination always showed the lowest mean body weight (P<0.05) in three (A18Slow, A18Fast & B18Slow) of the four groups tested. Individuals with DGG haplotipe of MyoD-1 gen have a 25,5% and those with CCA haplotipe of MyoD- 2gen showed 14-18% less on mean body weight. Although further studies are need to validate the role of these 3 SNPs as marker for body weight, the polymorphism-trait association established in this work create promising expectations on the use of these variants as genetic tool for future giltead seabream breeding programs.

Keywords: growth, MyoD-1 and MyoD-2 genes, selective breeding, SNP-haplotype

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Authors: Mina Malak Zakaria Henin

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The finite detail evaluation of magnetic fields in electromagnetic devices shows that the machine cores revel in extraordinary flux patterns consisting of alternating and rotating fields. The rotating fields are generated in different configurations variety, among circular and elliptical, with distinctive ratios between the fundamental and minor axes of the flux locus. Experimental measurements on electrical metal uncovered one-of-a-kind flux patterns that divulge distinctive magnetic losses in the samples below the test. Therefore, electric machines require unique interest throughout the core loss calculation technique to bear in mind the flux styles. In this look, a circular rotational unmarried sheet tester is employed to measure the middle losses in the electric-powered metallic pattern of M36G29. The sample becomes exposed to alternating fields, circular areas, and elliptical fields with axis ratios of zero.2, zero. Four, 0.6 and 0.8. The measured statistics changed into applied on 6-4 switched reluctance motors at 3 distinctive frequencies of interest to the industry 60 Hz, 400 Hz, and 1 kHz. The effects reveal an excessive margin of error, which can arise at some point in the loss calculations if the flux pattern difficulty is overlooked. The mistake in exceptional components of the gadget associated with considering the flux styles may be around 50%, 10%, and a couple of at 60Hz, 400Hz, and 1 kHz, respectively. The future paintings will focus on the optimization of gadget geometrical shape, which has a primary effect on the flux sample on the way to decrease the magnetic losses in system cores.

Keywords: converters, electric machines, MEA (more electric aircraft), PES (power electronics systems) synchronous machine, vector control Multi-machine/ Multi-inverter, matrix inverter, Railway tractionalternating core losses, finite element analysis, rotational core losses

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Authors: Prabhavathi Sundaram, Heidi Abrahamse

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In recent years, nanotechnology coupled with photodynamic therapy (PDT) has received considerable attention in terms of improving the effectiveness of drug delivery in cancer therapeutics. The development of functionalized single-walled carbon nanotubes (SWCNTs) has become revolutionary in targeted photosensitizers delivery since it improves the therapeutic index of drugs. The objective of this study was to prepare, characterize and evaluate the potential of functionalized SWCNTs using hyaluronic acid and loading it with photosensitizer and to effectively target colon cancer cells. The single-walled carbon nanotubes were covalently functionalized with hyaluronic acid and the loaded photosensitizer by non-covalent interaction. The photodynamic effect of SWCNTs is detected under laser irradiation in vitro. The hyaluronic acid-functionalized nanocomposites had a good affinity with CD44 receptors, and it avidly binds on to the surface of CACO-2 cells. The cellular uptake of nanocomposites was studied using fluorescence microscopy using lyso tracker. The anticancer activity of nanocomposites was analyzed in CACO-2 cells using different studies such as cell morphology, cell apoptosis, and nuclear morphology. The combined effect of nanocomposites and PDT improved the therapeutic effect of cancer treatment. The study suggested that the nanocomposites and PDT have great potential in the treatment of colon cancer.

Keywords: colon cancer, hyaluronic acid, single walled carbon nanotubes, photosensitizers, photodynamic therapy

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Authors: Zekun Lin, Xun Li

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Silicon photonics has gained much interest and extensive research for a promising aspect for fabricating compact, high-speed and low-cost photonic devices compatible with complementary metal-oxide-semiconductor (CMOS) process. Despite the remarkable progress made on the development of silicon photonics, high-performance, cost-effective, and reliable silicon laser sources are still missing. In this work, we present a 1550 nm III-V/silicon laser design with stable single-mode lasing property and robust and high-efficiency vertical coupling. The InP cavity consists of two uniform Bragg grating sections at sides for mode selection and feedback, as well as a central second-order grating for surface emission. A grating coupler is etched on the SOI waveguide by which the light coupling between the parallel III-V and SOI is reached vertically rather than by evanescent wave coupling. Laser characteristic is simulated and optimized by the traveling-wave model (TWM) and a Green’s function analysis as well as a 2D finite difference time domain (FDTD) method for the coupling process. The simulation results show that single-mode lasing with SMSR better than 48dB is achievable, and the threshold current is less than 15mA with a slope efficiency of around 0.13W/A. The coupling efficiency is larger than 42% and possesses a high tolerance with less than 10% reduction for 10 um horizontal or 15 um vertical dislocation. The design can be realized by standard flip-chip bonding techniques without co-fabrication of III-V and silicon or precise alignment.

Keywords: III-V/silicon integration, silicon photonics, single mode laser, vertical coupling

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Authors: Sima Parvizi Omran, Rezvan Tavakoli, Mahnaz Safari, Mohammadreza Aghasadeghi, Abolfazl Fateh, Pooneh Rahimi

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Background: SARS-CoV-2, a single-stranded RNA betacoronavirus causes the global outbreak of coronavirus disease 2019 (COVID-19). Several clinical and scientific concerns are raised by this pandemic. Genetic factors can contribute to pathogenesis and disease susceptibility. There are single nucleotide polymorphisms (SNPs) in many of the genes in the immune system that affect the expression of specific genes or functions of some proteins related to immune responses against viral infections. In this study, we analyzed the impact of polymorphism in the interferon alpha and beta receptor subunit 2 (IFNAR2) and dipeptidyl peptidase 9 (Dpp9) genes and clinical parameters on the susceptibility and resistance to Coronavirus disease (COVID-19). Methods: A total of 330- SARS-CoV-2 positive patients (188 survivors and 142 nonsurvivors) were included in this study. All single-nucleotide polymorphisms (SNPs) on IFNAR2 (rs2236757) and Dpp9 (rs2109069) were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results: In survivor patients, the frequency of the favourable genotypes of IFNAR2 SNP (rs2236757 GC) was significantly higher than in nonsurvivor patients, and also Dpp9 (rs2109069 AT) genotypes were associated with the severity of COVID-19 infection. Conclusions: This study demonstrated that the severity of COVID- 19 patients was strongly associated with clinical parameters and unfavourable IFNAR2, Dpp9 SNP genotypes. In order to establish the relationship between host genetic factors and the severity of COVID-19 infection, further studies are needed in multiple parts of the world.

Keywords: SARS-CoV-2, COVID-19, interferon alpha and beta receptor subunit 2, dipeptidyl peptidase 9, single-nucleotide polymorphisms

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Authors: Frederic Jumelle, Kelvin So, Didan Deng

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In this paper, we are introducing a model of artificial general intelligence (AGI), the functional neural network (FNN), for modeling human decision-making processes. The FNN is composed of multiple artificial mirror neurons (AMN) racing in the network. Each AMN has a similar structure programmed independently by the users and composed of an intention wheel, a motor core, and a sensory core racing at a specific velocity. The mathematics of the node’s formulation and the racing mechanism of multiple nodes in the network will be discussed, and the group decision process with fuzzy logic and the transformation of these conceptual methods into practical methods of simulation and in operations will be developed. Eventually, we will describe some possible future research directions in the fields of finance, education, and medicine, including the opportunity to design an intelligent learning agent with application in AGI. We believe that FNN has a promising potential to transform the way we can compute decision-making and lead to a new generation of AI chips for seamless human-machine interactions (HMI).

Keywords: neural computing, human machine interation, artificial general intelligence, decision processing

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Authors: Abdorrasoul Malekpour, Mohammad Ghorbani Mojtaba Mortazavi, Mohammadreza Fattahi, Mohammad Hassan Meshkibaf, Ali Fakhrzad, Saeid Salehi, Saeideh Zahedi, Amir Ahmadimoghaddam, Parviz Farzadnia Dr., Mohammadreza Hajyani Asl Bs

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Hepatitis B as an infectious disease has eight main genotypes (A–H). The aim of this study is to Bioinformatically identify Rare Codon Clusters (RCC) in proteins structure of HBV. For detection of protein family accession numbers (Pfam) of HBV proteins; used of uni-prot database and Pfam search tool were used. Obtained Pfam IDs were analyzed in Sherlocc program and RCCs in HBV proteins were detected. In further, the structures of TrEMBL entries proteins studied in PDB database and 3D structures of the HBV proteins and locations of RCCs were visualized and studied using Swiss PDB Viewer software. Pfam search tool have found nine significant hits and 0 insignificant hits in 3 frames. Results of Pfams studied in the Sherlocc program show this program not identified RCCs in the external core antigen (PF08290) and truncated HBeAg protein (PF08290). By contrast the RCCs become identified in Hepatitis core antigen (PF00906) Large envelope protein S (PF00695), X protein (PF00739), DNA polymerase (viral) N-terminal domain (PF00242) and Protein P (Pf00336). In HBV genome, seven RCC identified that found in hepatitis core antigen, large envelope protein S and DNA polymerase proteins and proteins structures of TrEMBL entries sequences that reported in Sherlocc program outputs are not complete. Based on situation of RCC in structure of HBV proteins, it suggested those RCCs are important in HBV life cycle. We hoped that this study provide a new and deep perspective in protein research and drug design for treatment of HBV.

Keywords: rare codon clusters, hepatitis B virus, bioinformatic study, infectious disease

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Authors: J. Y. Sun, H. Z. Shen

Abstract:

We study the photon blockade at exceptional points for a non-Hermitian optomechanical system coupled to the driven whispering-gallery-mode microresonator with two nanoparticles under the weak optomechanical coupling approximation, where exceptional points emerge periodically by controlling the relative angle of the nanoparticles. We find that conventional photon blockade occurs at exceptional points for the eigenenergy resonance of the single-excitation subspace driven by a laser field and discuss the physical origin of conventional photon blockade. Under the weak driving condition, we analyze the influences of the different parameters on conventional photon blockade. We investigate conventional photon blockade at nonexceptional points, which exists at two optimal detunings due to the eigenstates in the single-excitation subspace splitting from one (coalescence) at exceptional points to two at nonexceptional points. Unconventional photon blockade can occur at nonexceptional points, while it does not exist at exceptional points since the destructive quantum interference cannot occur due to the two different quantum pathways to the two-photon state not being formed. The realization of photon blockade in our proposal provides a viable and flexible way for the preparation of single-photon sources in the non-Hermitian optomechanical system.

Keywords: optomechanical systems, photon blockade, non-hermitian, exceptional points

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Authors: Taylor Harris

Abstract:

Gustilo-anderson grade III tibial fractures are exquisitely difficult injuries to manage as they require extensive soft tissue repair in addition to fracture fixation. These injuries are best managed collaboratively by Orthopedic and Plastic surgeons. While utilizing an Orthoplastics approach has decreased the rates of adverse outcomes in these injuries, there is a large amount of variation in exactly how an Orthoplastics team approaches complex cases such as these. It is sometimes recommended that definitive bone fixation and soft tissue coverage be completed simultaneously in a single-stage manner, but there is a paucity of large scale studies to provide evidence to support this recommendation. It is the aim of this study to report the outcomes of a single-stage "fix-and-flap" approach through a systematic review of the available literature. Hopefully, this better informs an evidence-based Orthoplastics approach to managing open tibial fractures. Systematic review of the literature was performed. Medline and Google Scholar were used and all studies published since 2000, in English were included. 103 studies were initially evaluated for inclusion. Reference lists of all included studies were also examined for potentially eligible studies. Gustilo grade III tibial shaft fractures in adults that were managed with a single-stage Orthoplastics approach were identified and evaluated with regard to outcomes of interest. Exclusion criteria included studies with patients <16 years old, case studies, systemic reviews, meta-analyses. Primary outcomes of interest were the rates of deep infections and rates of limb salvage. Secondary outcomes of interest included time to bone union, rates of non-union, and rates of re-operation. 15 studies were eligible. 11 of these studies reported rates of deep infection as an outcome, with rates ranging from 0.98%-20%. The pooled rate between studies was 7.34%. 7 studies reported rates of limb salvage with a range of 96.25%-100%. The pooled rate of the associated studies was 97.8%. 6 reported rates of non-union with a range of 0%-14%, a pooled rate of 6.6%. 6 reported time to bone union with a range of 24 to 40.3 weeks and a pooled average time of 34.2 weeks, and 4 reported rates of reoperation ranging from 7%-55%, with a pooled rate of 31.1%. A few studies that compared a single stage to a multi stage approach side-by-side unanimously favored the single stage approach. Outcomes of Gustilo grade III open tibial fractures utilizing an Orthoplastics approach that is specifically done in a single-stage produce low rates of adverse outcomes. Large scale studies of Orthoplastic collaboration that were not completed in strictly a single stage, or were completed in multiple stages, have not reported as favorable outcomes. We recommend that not only should Orthopedic surgeons and Plastic surgeons collaborate in the management of severe open tibial fracture, but they should plan to undergo definitive fixation and coverage in a single-stage for improved outcomes.

Keywords: orthoplastic, gustilo grade iii, single-stage, trauma, systematic review

Procedia PDF Downloads 86

Authors: Pongsiri Kingkan

Abstract:

This research aims to study the Readiness of Thai Restaurant in Bangkok in Applying for Certification of Halal Food Services Standard for Tourism. This research was conduct by using mix methodology; both quantitative and qualitative data were used. 420 questionnaires were used as tools to collected data from the samples, the restaurant employees. The results were divided into two parts, the demographic data and the Readiness of Thai Restaurant in Bangkok in Applying for Certification of Halal Food Services Standard for Tourism. The majority of samples are single female age between 18–30 years old, who earn about 282.40 US dollars a month. The result of Thai restaurant readiness study demonstrated that readiness in foods and restaurant operating processes were scored at the lowest level. Readiness in social responsibility, food contact persons and food materials were rated at the low level. The readiness of utensils and kitchen tools, waste management, environmental management, and the availability of space to implement the establishment of halal food were scored at the average level. Location readiness, foods service safety and the relationship with the local community were rated at high level. But interestingly there is none of them rated at the highest level.

Keywords: availability, Bangkok, halal, Thai restaurant, readiness

Procedia PDF Downloads 316

Authors: Arunas Stirke, Neringa Bakute, Gatis Mozolevskis

Abstract:

A technology of microfluidics is an emerging tool in the field of biology, medicine and chemistry. Microfluidic device is also known as ‘lab-on-a-chip’ technology [1]. In moving from macro- to microscale, there is unprecedented control over spatial and temporal gradients and patterns that cannot be captured in conventional Petri dishes and well plates [2]. However, there is not a single standard microfluidic chip designated for all purposes – every different field of studies needs a specific microchip with certain geometries, inlet/outlet, channel depth and other parameters to precisely regulate the required function. Since our group is studying an effect of pulsed electric field (PEF) to the cells, we have manufactured a microfluidic chip designated for high-throughput electroporation of cells. In our microchip, a cell culture chamber is divided into two parallel channels by a membrane, meanwhile electrodes for electroporation are attached to the wall of the channels. Both microchannels have their own inlet and outlet, enabling injection of transfection material separately. Our perspective is to perform electroporation of mammalian cells in two different ways: (1) plasmid and cells are injected in the same microchannel and (2) injected into separate microchannels. Moreover, oxygen and pH sensors are integrated on order to analyse cell viability parameters after PEF treatment.

Keywords: microfluidics, chip, fabrication, electroporation

Procedia PDF Downloads 83

Authors: Seyede Sanaz Seyedebrahimi, Shima Rahimi, Shohreh Fakhari, Ali Jalili

Abstract:

Background: CXCR4, as a chemokine receptor, plays well-known roles in various types of cancers. Several studies have been conducted to overcome CXCR4 axis acts in multiple myeloma (MM) pathogenesis and progression. Dexamethasone, a standard treatment for multiple myeloma, has been shown to increase CXCR4 levels in multiple myeloma cell lines. Herein, we focused on the effects of metformin and dexamethasone on CXCR4 at the cellular level and the migration rate of cell lines after exposure to a combination compared to single-agent models. Materials and Method: Multiple myeloma cell lines (U266 and RPMI8226) were cultured with different metformin and dexamethasone concentrations in single-agent and combination models. The simultaneous combination doses were calculated by CompuSyn software. Cell surface and mRNA expression of CXCR4 were determined using flow cytometry and the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay, respectively. The Transwell cell migration assay evaluated the migration ability. Results: In concurred with previous studies, our results showed a dexamethasone up-regulation effect on CXCR4 in a dose-dependent manner. Although, the metformin single-agent model could reduce CXCR4 expression of U266 and RPMI8226 in cell surface and mRNA expression level. Moreover, the administration of metformin and dexamethasone simultaneously exerted a higher suppression effect on CXCR4 expression than the metformin single-agent model. The migration rate through the combination model's matrigel membrane was remarkably lower than the metformin and dexamethasone single-agent model. Discussion: According to our findings, the combination of metformin and dexamethasone effectively inhibited dexamethasone-induced CXCR4 expression in multiple myeloma cell lines. As a result, metformin may be counted as an alternative medicine combined with other chemotherapies to combat multiple myeloma. However, more research is required.

Keywords: CXCR4, dexamethasone, metformin, migration, multiple myeloma

Procedia PDF Downloads 156

Authors: Aswan Aswan

Abstract:

Ichnofossils were examined based on two wells cores of Jurassic sediment from Bintuni Basin, West Papua, Indonesia. The cores are the Jurassic interval and known as the potential reservoir interval in this area. Representative of 18 ichnogenera was recorded including forms assigned to Arenicolites, Asterosoma, Bergaueria, Chondrites, cryptic bioturbation, Glossifungites, Lockeia, Ophiomorpha, Palaeophycus, Phycosiphon, Planolites, Rhizocorallium, Rosselia, root structure, Skolithos, Teichicnus, Thalassinoides, and Zoophycos. The two cores represent a depositional system that is dominated by tidal flat, shallow marine shelf continuum possibly crossed by estuaries or tidal shoals channels. From the first core identified two deepening cycles. The shallow one is a shallow marine with tidal influence while the deeper one attached to the shelf. Shallow interval usually indicates by appearances of Ophiomorpha and Glossifungites while the deeper shallow marine interval signs by the abundance of Phycosiphon. The second core reveals eight deepening cycles.

Keywords: ichnofossil, Jurassic, sediment, reservoir, Bintuni, Indonesia, West Papua

Procedia PDF Downloads 362

Authors: Priyanka Agrawal, Janou Koskamp, Amir Raoof, Mariette Wolthers

Abstract:

Calcite is the main mineral found in carbonate rocks, which form significant hydrocarbon reservoirs and subsurface repositories for CO2 sequestration. The injected CO2 mixes with the reservoir fluid and disturbs the geochemical equilibrium, triggering calcite dissolution. Different combinations of fluid chemistry and injection rate may therefore result in different evolution of porosity, permeability and dissolution patterns. To model the changes in porosity and permeability Kozeny-Carman equation K∝〖(∅)〗^n is used, where K is permeability and ∅ is porosity. The value of n is mostly based on experimental data or pore network models. In pore network models, this derivation is based on accuracy of relation used for conductivity and pore volume change. In fact, at a single pore scale, this relationship is the result of the pore shape development due to dissolution. We have prepared a new reactive transport model for a single pore which simulates the complex chemical reaction of carbonic-acid induced calcite dissolution and subsequent pore-geometry evolution at a single pore scale. We use COMSOL Multiphysics package 5.3 for the simulation. COMSOL utilizes the arbitary-Lagrangian Eulerian (ALE) method for the free-moving domain boundary. We examined the effect of flow rate on the evolution of single pore shape profiles due to calcite dissolution. We used three flow rates to cover diffusion dominated and advection-dominated transport regimes. The fluid in diffusion dominated flow (Pe number 0.037 and 0.37) becomes less reactive along the pore length and thus produced non-uniform pore shapes. However, for the advection-dominated flow (Pe number 3.75), the fast velocity of the fluid keeps the fluid relatively more reactive towards the end of the pore length, thus yielding uniform pore shape. Different pore shapes in terms of inlet opening vs overall pore opening will have an impact on the relation between changing volumes and conductivity. We have related the shape of pore with the Pe number which controls the transport regimes. For every Pe number, we have derived the relation between conductivity and porosity. These relations will be used in the pore network model to get the porosity and permeability variation.

Keywords: single pore, reactive transport, calcite system, moving boundary

Procedia PDF Downloads 374