Search results for: consistent and concentrated mass matrices
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5473

Search results for: consistent and concentrated mass matrices

3433 The Strategy of Orbit Avoidance for Optical Remote Sensing Satellite

Authors: Dianxun Zheng, Wuxing Jing, Lin Hetong

Abstract:

Optical remote sensing satellite, always running on the Sun-synchronous orbit, equipped laser warning equipment to alert CCD camera from laser attack. There have three ways to protect the CCD camera, closing the camera cover satellite attitude maneuver and satellite orbit avoidance. In order to enhance the safety of optical remote sensing satellite in orbit, this paper explores the strategy of satellite avoidance. The avoidance strategy is expressed as the evasion of pre-determined target points in the orbital coordinates of virtual satellite. The so-called virtual satellite is a passive vehicle which superposes a satellite at the initial stage of avoidance. The target points share the consistent cycle time and the same semi-major axis with the virtual satellite, which ensures the properties of the Sun-synchronous orbit remain unchanged. Moreover, to further strengthen the avoidance capability of satellite, it can perform multi-object avoid maneuvers. On occasions of fulfilling the orbit tasks of the satellite, the orbit can be restored back to virtual satellite through orbit maneuvers. There into, the avoid maneuvers adopts pulse guidance. and the fuel consumption is also optimized. The avoidance strategy discussed in this article is applicable to avoidance for optical remote sensing satellite when encounter the laser hostile attacks.

Keywords: optical remote sensing satellite, always running on the sun-synchronous

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3432 Optimal Rest Interval between Sets in Robot-Based Upper-Arm Rehabilitation

Authors: Virgil Miranda, Gissele Mosqueda, Pablo Delgado, Yimesker Yihun

Abstract:

Muscular fatigue affects the muscle activation that is needed for producing the desired clinical outcome. Integrating optimal muscle relaxation periods into a variety of health care rehabilitation protocols is important to maximize the efficiency of the therapy. In this study, four muscle relaxation periods (30, 60, 90, and 120 seconds) and their effectiveness in producing consistent muscle activation of the muscle biceps brachii between sets of elbow flexion and extension task was investigated among a sample of 10 subjects with no disabilities. The same resting periods were then utilized in a controlled exoskeleton-based exercise for a sample size of 5 subjects and have shown similar results. On average, the muscle activity of the biceps brachii decreased by 0.3% when rested for 30 seconds, and it increased by 1.25%, 0.76%, and 0.82% when using muscle relaxation periods of 60, 90, and 120 seconds, respectively. The preliminary results suggest that a muscle relaxation period of about 60 seconds is needed for optimal continuous muscle activation within rehabilitation regimens. Robot-based rehabilitation is good to produce repetitive tasks with the right intensity, and knowing the optimal resting period will make the automation more effective.

Keywords: rest intervals, muscle biceps brachii, robot rehabilitation, muscle fatigue

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3431 Synthesis and Pharmacological Activity of Some Oxyindole Derivatives

Authors: Vivek Singh Bhadauria, Abhishek Pandey

Abstract:

Indole-2,3-diones are known for their various biological activities. By suitable control of a substituent, different novel indole-2,3-diones were synthesized. In this present study, various Schiff and Mannich bases were synthesized and characterized, and evaluated their for different pharmacological activities. The compounds were prepared by reacting indole-2,3-dione with benzyl chloride and 4-substituted thiosemicarbazides. All the synthesized compounds were characterized by the TLC, MP, Elemental analysis, FTIR, 1H-NMR and Mass spectroscopy. The compounds have been evaluated for their anticancer, antituberculosis, anticonvulsant, antiinflammatory as well as anti-SARS activity and the results are presented. Some of compounds possessed different pharmacological activity at a concentration of 200 mg/kg body weight and even at lower concentration.

Keywords: indoles, isatin, NMR, biological activities

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3430 Study of the Phenomenon Nature of Order and Disorder in BaMn(Fe/V)F7 Fluoride Glass by the Hybrid Reverse Monte Carlo Method

Authors: Sidi Mohamed Mesli, Mohamed Habchi, Mohamed Kotbi, Rafik Benallal, Abdelali Derouiche

Abstract:

Fluoride glasses with a nominal composition of BaMnMF7 (M = FeV assuming isomorphous replacement) have been structurally modelled through the simultaneous simulation of their neutron diffraction patterns by a reverse Monte Carlo (RMC) model and by a Rietveld for disordered materials (RDM) method. Model is consistent with an expected network of interconnected [MF6] polyhedra. The RMC results are accompanied by artificial satellite peaks. To remedy this problem, we use an extension of the RMC algorithm, which introduces an energy penalty term in acceptance criteria. This method is called the Hybrid Reverse Monte Carlo (HRMC) method. The idea of this paper is to apply the (HRMC) method to the title glasses, in order to make a study of the phenomenon nature of order and disorder by displaying and discussing the partial pair distribution functions (PDFs) g(r). We suggest that this method can be used to describe average correlations between components of fluoride glass or similar system.

Keywords: fluoride glasses, RMC simulation, neutron scattering, hybrid RMC simulation, Lennard-Jones potential, partial pair distribution functions

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3429 Sensitivity Assessment of Spectral Salinity Indices over Desert Sabkha of Western UAE

Authors: Rubab Ammad, Abdelgadir Abuelgasim

Abstract:

UAE typically lies in one of the aridest regions of the world and is thus home to geologic features common to such climatic conditions including vast open deserts, sand dunes, saline soils, inland Sabkha and coastal Sabkha. Sabkha are characteristic salt flats formed in arid environment due to deposition and precipitation of salt and silt over sand surface because of low laying water table and rates of evaporation exceeding rates of precipitation. The study area, which comprises of western UAE, is heavily concentrated with inland Sabkha. Remote sensing is conventionally used to study the soil salinity of agriculturally degraded lands but not so broadly for Sabkha. The focus of this study was to identify these highly saline Sabkha areas on remotely sensed data, using salinity indices. The existing salinity indices in the literature have been designed for agricultural soils and they have not frequently used the spectral response of short-wave infra-red (SWIR1 and SWIR2) parts of electromagnetic spectrum. Using Landsat 8 OLI data and field ground truthing, this study formulated indices utilizing NIR-SWIR parts of spectrum and compared the results with existing salinity indices. Most indices depict reasonably good relationship between salinity and spectral index up until a certain value of salinity after which the reflectance reaches a saturation point. This saturation point varies with index. However, the study findings suggest a role of incorporating near infra-red and short-wave infra-red in salinity index with a potential of showing a positive relationship between salinity and reflectance up to a higher salinity value, compared to rest.

Keywords: Sabkha, salinity index, saline soils, Landsat 8, SWIR1, SWIR2, UAE desert

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3428 Essential Oils of Polygonum L. Plants Growing in Kazakhstan and Their Antibacterial and Antifungal Activity

Authors: Dmitry Yu. Korulkin, Raissa A. Muzychkina

Abstract:

Bioactive substances of plant origin can be one of the advanced means of solution to the issue of combined therapy to inflammation. The main advantages of medical plants are softness and width of their therapeutic effect on an organism, the absence of side effects and complications even if the used continuously, high tolerability by patients. Moreover, medial plants are often the only and (or) cost-effective sources of natural biologically active substances and medicines. Along with other biologically active groups of chemical compounds, essential oils with wide range of pharmacological effects became very ingrained in medical practice. Essential oil was obtained by the method hydrodistillation air-dry aerial part of Polygonum L. plants using Clevenger apparatus. Qualitative composition of essential oils was analyzed by chromatography-mass-spectrometry method using Agilent 6890N apparatus. The qualitative analysis is based on the comparison of retention time and full mass-spectra with respective data on components of reference oils and pure compounds, if there were any, and with the data of libraries of mass-spectra Wiley 7th edition and NIST 02. The main components of essential oil are for: Polygonum amphibium L. - γ-terpinene, borneol, piperitol, 1,8-cyneole, α-pinene, linalool, terpinolene and sabinene; Polygonum minus Huds. Fl. Angl. – linalool, terpinolene, camphene, borneol, 1,8-cyneole, α-pinene, 4-terpineol and 1-octen-3-ol; Polygonum alpinum All. – camphene, sabinene, 1-octen-3-ol, 4-carene, p- and o-cymol, γ-terpinene, borneol, -terpineol; Polygonum persicaria L. - α-pinene, sabinene, -terpinene, 4-carene, 1,8-cyneole, borneol, 4-terpineol. Antibacterial activity was researched relating to strains of gram-positive bacteria Staphylococcus aureus, Bacillus subtilis, Streptococcus agalacticae, relating to gram-negative strain Escherichia coli and to yeast fungus Сandida albicans using agar diffusion method. The medicines of comparison were gentamicin for bacteria and nystatin for yeast fungus Сandida albicans. It has been shown that Polygonum L. essential oils has moderate antibacterial effect to gram-positive microorganisms and weak antifungal activity to Candida albicans yeast fungus. At the second stage of our researches wound healing properties of ointment form of 3% essential oil was researched on the model of flat dermal wounds. To assess the influence of essential oil on healing processes the model of flat dermal wound. The speed of wound healing on rats of different groups was judged based on assessment the area of a wound from time to time. During research of wound healing properties disturbance of integral in neither group: general condition and behavior of animals, food intake, and excretion. Wound healing action of 3% ointment on base of Polygonum L. essential oil and polyethyleneglycol is comparable with the action of reference substances. As more favorable healing dynamics was observed in the experimental group than in control group, the tested ointment can be deemed more promising for further detailed study as wound healing means.

Keywords: antibacterial, antifungal, bioactive substances, essential oils, isolation, Polygonum L.

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3427 Antioxidant Activity Studies of Novel Schiff and Mannich Bases

Authors: D. J. Madhu Kumar, D. Jagadeesh Prasad, Sana Sheik, E. P. Rejeesh

Abstract:

A series of Mannich bases derived from 1,2,4-triazole(3a-k and 4a-k) are synthesized by treating a Schiff base with various substituted primary/secondary amines and formaldehyde. The Schiff base is prepared by treating 3-methyl-4-amino-5-mercapto-1,2,4-triazole with 3,4-dimethoxybenzaldehyde in the presence of acid catalyst. The triazole is prepared by treating acetic acid with thiocarbohydrazide at reflux temperature. All the synthesized samples are characterised by FT-IR, 1H-NMR, and LC-MASS spectral studies and screened for their anti-oxidant activity.

Keywords: mannich bases, anti-oxidant activity, schiff base, triazole

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3426 Wet Spun Graphene Fibers With Silver Nanoparticles For Flexible Electronic Applications

Authors: Syed W. Hasan, Zhiqun Tian

Abstract:

Wet spinning provides a facile and economic route to fabricate graphene nanofibers (GFs) on mass scale. Nevertheless, the pristine GFs exhibit significantly low electrical and mechanical properties owing to stacked graphene sheets and weak inter-atomic bonding. In this report, we present highly conductive Ag-decorated-GFs (Ag/GFs). The SEM micrographs show Ag nanoparticles (NPs) (dia ~10 nm) are homogeneously distributed throughout the cross-section of the fiber. The Ag NPs provide a conductive network for the electrons flow raising the conductivity to 1.8(10^4) S/m which is 4 times higher than the pristine GFs. Our results surpass the conductivities of graphene fibers doped with CNTs, Nanocarbon, fullerene, and Cu. The chemical and structural attributes of Ag/GFs are further elucidated through XPS, AFM and Raman spectroscopy.

Keywords: Ag nanoparticles, Conductive fibers, Graphene, Wet spinning

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3425 Multi-Particle Finite Element Modelling Simulation Based on Cohesive Zone Method of Cold Compaction Behavior of Laminar Al and NaCl Composite Powders

Authors: Yanbing Feng, Deqing Mei, Yancheng Wang, Zichen Chen

Abstract:

With the advantage of low volume density, high specific surface area, light weight and good permeability, porous aluminum material has the potential to be used in automotive, railway, chemistry and construction industries, etc. A layered powder sintering and dissolution method were developed to fabricate the porous surface Al structure with high efficiency. However, the densification mechanism during the cold compaction of laminar composite powders is still unclear. In this study, multi particle finite element modelling (MPFEM) based on the cohesive zone method (CZM) is used to simulate the cold compaction behavior of laminar Al and NaCl composite powders. To obtain its densification mechanism, the macro and micro properties of final compacts are characterized and analyzed. The robustness and accuracy of the numerical model is firstly verified by experimental results and data fitting. The results indicate that the CZM-based multi particle FEM is an effective way to simulate the compaction of the laminar powders and the fracture process of the NaCl powders. In the compaction of the laminar powders, the void is mainly filled by the particle rearrangement, plastic deformation of Al powders and brittle fracture of NaCl powders. Large stress is mainly concentrated within the NaCl powers and the contact force network is formed. The Al powder near the NaCl powder or the mold has larger stress distribution on its contact surface. Therefore, the densification process of cold compaction of laminar Al and NaCl composite powders is successfully analyzed by the CZM-based multi particle FEM.

Keywords: cold compaction, cohesive zone, multi-particle FEM, numerical modeling, powder forming

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3424 The Potential Role of Industrialized Building Systems in Malaysian Sustainable Construction: Awareness and Barriers

Authors: Aawag Mohsen Al-Awag, Wesam Salah Alaloul, M. S. Liew

Abstract:

Industrialized building system (IBS) is a method of construction with concentrated practices consisting of techniques, products, and a set of linked elements which operate collectively to accomplish objectives. The Industrialised Building System (IBS) has been recognised as a viable method for improving overall construction performance in terms of quality, cost, safety and health, waste reduction, and productivity. The Malaysian construction industry is considered one of the contributors to the development of the country. The acceptance level of IBS is still below government expectations. Thus, the Malaysian government has been continuously encouraging the industry to use and implement IBS. Conventional systems have several drawbacks, including project delays, low economic efficiency, excess inventory, and poor product quality. When it comes to implementing IBS, construction companies still face several obstacles and problems, notably in terms of contractual and procurement concerns, which leads to the low adoption of IBS in Malaysia. There are barriers to the acceptance of IBS technology, focused on awareness of historical failure and risks connected to IBS practices to provide enhanced performance. Therefore, the transformation from the existing conventional building systems to the industrialized building systems (IBS) is needed more than ever. The flexibility of IBS in Malaysia’s construction industry is very low due to numerous shortcomings and obstacles. Due to its environmental, economic, and social benefits, IBS could play a significant role in the Malaysian construction industry in the future. This paper concentrates on the potential role of IBS in sustainable construction practices in Malaysia. It also highlights the awareness, barriers, advantages, and disadvantages of IBS in the construction sector. The study concludes with recommendations for Malaysian construction stakeholders to encourage and increase the utilization of industrialised building systems.

Keywords: construction industry, industrialized building system, barriers, advantages and disadvantages, construction, sustainability, Malaysia

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3423 Impact of Diabetes Mellitus Type 2 on Clinical In-Stent Restenosis in First Elective Percutaneous Coronary Intervention Patients

Authors: Leonard Simoni, Ilir Alimehmeti, Ervina Shirka, Endri Hasimi, Ndricim Kallashi, Verona Beka, Suerta Kabili, Artan Goda

Abstract:

Background: Diabetes Mellitus type 2, small vessel calibre, stented length of vessel, complex lesion morphology, and prior bypass surgery have resulted risk factors for In-Stent Restenosis (ISR). However, there are some contradictory results about body mass index (BMI) as a risk factor for ISR. Purpose: We want to identify clinical, lesional and procedural factors that can predict clinical ISR in our patients. Methods: Were enrolled 759 patients who underwent first-time elective PCI with Bare Metal Stents (BMS) from September 2011 to December 2013 in our Department of Cardiology and followed them for at least 1.5 years with a median of 862 days (2 years and 4 months). Only the patients re-admitted with ischemic heart disease underwent control coronary angiography but no routine angiographic control was performed. Patients were categorized in ISR and non-ISR groups and compared between them. Multivariate analysis - Binary Logistic Regression: Forward Conditional Method was used to identify independent predictive risk factors. P was considered statistically significant when <0.05. Results: ISR compared to non-ISR individuals had a significantly lower BMI (25.7±3.3 vs. 26.9±3.7, p=0.004), higher risk anatomy (LM + 3-vessel CAD) (23% vs. 14%, p=0.03), higher number of stents/person used (2.1±1.1 vs. 1.75±0.96, p=0.004), greater length of stents/person used (39.3±21.6 vs. 33.3±18.5, p=0.01), and a lower use of clopidogrel and ASA (together) (95% vs. 99%, p=0.012). They also had a higher, although not statistically significant, prevalence of Diabetes Mellitus (42% vs. 32%, p=0.072) and a greater number of treated vessels (1.36±0.5 vs. 1.26±0.5, p=0.08). In the multivariate analysis, Diabetes Mellitus type 2 and multiple stents used were independent predictors risk factors for In-Stent Restenosis, OR 1.66 [1.03-2.68], p=0.039, and OR 1.44 [1.16-1.78,] p=0.001, respectively. On the other side higher BMI and use of clopidogrel and ASA together resulted protective factors OR 0.88 [0.81-0.95], p=0.001 and OR 0.2 [0.06-0.72] p=0.013, respectively. Conclusion: Diabetes Mellitus and multiple stents are strong predictive risk factors, whereas the use of clopidogrel and ASA together are protective factors for clinical In-Stent Restenosis. Paradoxically High BMI is a protective factor for In-stent Restenosis, probably related to a larger diameter of vessels and consequently a larger diameter of stents implanted in these patients. Further studies are needed to clarify this finding.

Keywords: body mass index, diabetes mellitus, in-stent restenosis, percutaneous coronary intervention

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3422 Assessment of Dimensions and Gully Recovery With GPS Receiver and RPA (Drone)

Authors: Mariana Roberta Ribeiro, Isabela de Cássia Caramello, Roberto Saverio Souza Costa

Abstract:

Currently, one of the most important environmental problems is soil degradation. This wear is the result of inadequate agricultural practices, with water erosion as the main agent. As the runoff water is concentrated in certain points, it can reach a more advanced stage, which are the gullies. In view of this, the objective of this work was to evaluate which methodology is most suitable for the purpose of elaborating a project for the recovery of a gully, relating work time, data reliability, and the final cost. The work was carried out on a rural road in Monte Alto - SP, where there is 0.30 hectares of area under the influence of a gully. For the evaluation, an aerophotogrammetric survey was used with RPA, with georeferenced points, and with a GNSS L1/L2 receiver. To assess the importance of georeferenced points, there was a comparison of altimetric data using the support points with altimetric data using only the aircraft's internal GPS. Another method used was the survey by conventional topography, where coordinates were collected by total station and L1/L2 Geodetic GPS receiver. Statistical analysis was performed using analysis of variance (ANOVA) using the F test (p<0.05), and the means between treatments were compared using the Tukey test (p<0.05). The results showed that the surveys carried out by aerial photogrammetry and by conventional topography showed no significant difference for the analyzed parameters. Considering the data presented, it is possible to conclude that, when comparing the parameters of accuracy, the final volume of the gully, and cost, for the purpose of elaborating a project for the recovery of a gully, the methodologies of aerial photogrammetric survey and conventional topography do not differ significantly. However, when working time, use of labor, and project detail are compared, the aerial photogrammetric survey proves to be more viable.

Keywords: drones, erosion, soil conservation, technology in agriculture

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3421 Bubble Growth in a Two Phase Upward Flow in a Miniature Tube

Authors: R. S. Hassani, S. Chikh, L. Tadrist, S. Radev

Abstract:

A bubbly flow in a vertical miniature tube is analyzed theoretically. The liquid and gas phase are co-current flowing upward. The gas phase is injected via a nozzle whose inner diameter is 0.11mm and it is placed on the axis of the tube. A force balance is applied on the bubble at its detachment. The set of governing equations are solved by use of Mathematica software. The bubble diameter and the bubble generation frequency are determined for various inlet phase velocities represented by the inlet mass quality. The results show different behavior of bubble growth and detachment depending on the tube size.

Keywords: two phase flow, bubble growth, mini-channel, generation frequency

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3420 Chemical Composition and Antioxidant Properties of Daucus Gracilis Extracts

Authors: El Kolli Meriem, Laouer Hocine, Sahli Farida, Akkal Salah, El Kolli Hayet

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The aerial parts of Daucus gracilis (Apiaceae) were subjected to hydrodistillation by a Clevenger apparatus to obtain the essential oil (EO) which has been analyzed by Gas Chromatography (GC) and GC coupled with mass spectrometry. The antioxidant properties of this EO and D. gracilis methanolic extract were studied by both of the free diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and the reducing power techniques. The dominant constituents of the EO were the elemicin (35.3 %) and the geranyl acetate (26.8 %). Both of EO and methanolic extract showed important antioxidant properties with respectively IC50 of 0,002 mg/ml and 0.06 mg/ml. They showed also a reducing power dose-dependent.

Keywords: daucus gracilis, apiaceae, essential oil, antioxidant activity

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3419 Aberrant Consumer Behavior in Seller’s and Consumer’s Eyes: Newly Developed Classification

Authors: Amal Abdelhadi

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Consumer misbehavior evaluation can be markedly different based on a number of variables and different from one environment to another. Using three aberrant consumer behavior (ACB) scenarios (shoplifting, stealing from hotel rooms and software piracy) this study aimed to explore Libyan seller and consumers of ACB. Materials were collected by using a multi-method approach was employed (qualitative and quantitative approaches) in two fieldwork phases. In the phase stage, a qualitative data were collected from 26 Libyan sellers’ by face-to-face interviews. In the second stage, a consumer survey was used to collect quantitative data from 679 Libyan consumers. This study found that the consumer’s and seller’s evaluation of ACB are not always consistent. Further, ACB evaluations differed based on the form of ACB. Furthermore, the study found that not all consumer behaviors that were considered as bad behavior in other countries have the same evaluation in Libya; for example, software piracy. Therefore this study suggested a newly developed classification of ACB based on marketers’ and consumers’ views. This classification provides 9 ACB types within two dimensions (marketers’ and consumers’ views) and three degrees of behavior evaluation (good, acceptable and misbehavior).

Keywords: aberrant consumer behavior, Libya, multi-method approach, planned behavior theory

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3418 A Study on the Role of Human Rights in the Aid Allocations of China and the United States

Authors: Shazmeen Maroof

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The study is motivated by a desire to investigate whether there is substance to claims that, relative to traditional donors, China disregards human rights considerations when allocating overseas aid. While the stated policy of the U.S. is that consideration of potential aid recipients’ respect for human rights is mandatory, some quantitative studies have cast doubt on whether this is reflected in actual allocations. There is a lack of academic literature that formally assesses the extent to which the two countries' aid allocations differ; which is essential to test whether the criticisms of China's aid policy in comparison to that of the U.S. are justified. Using data on two standard human rights measures, 'Political Terror Scale' and 'Civil Liberties', the study analyse the two donors’ aid allocations among 125 countries over the period 2000 to 2014. The bivariate analysis demonstrated that a significant share of China’s aid flow to countries with poor human rights record. At the same time, the U.S. seems little different in providing aid to these countries. The empirical results obtained from the Fractional Logit model also provided some support to the general pessimism regarding China’s provision of aid to countries with poor human rights record, yet challenge the optimists expecting better targeted aid from the U.S. These findings are consistent with the split between humanitarian and non-humanitarian aid and in the sample of countries whose human rights record is below some threshold level.

Keywords: China's aid policy, foreign aid allocation, human rights, United States Foreign Assistance Act

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3417 Computational Determination of the Magneto Electronic Properties of Ce₁₋ₓCuₓO₂ (x=12.5%): Emerging Material for Spintronic Devices

Authors: Aicha Bouhlala, Sabah Chettibi

Abstract:

Doping CeO₂ with transition metals is an effective way of tuning its properties. In the present work, we have performed self-consistent ab-initio calculation using the full-potential linearized augmented plane-wave method (FP-LAPW), based on the density functional theory (DFT) as implemented in the Wien2k simulation code to study the structural, electronic, and magnetic properties of the compound Ce₁₋ₓCuₓO₂ (x=12.5%) fluorite type oxide and to explore the effects of dopant Cu in ceria. The exchange correlation potential has been treated using the Perdew-Burke-Eenzerhof revised of solid (PBEsol). In structural properties, the equilibrium lattice constant is observed for the compound, which exists within the value of 5.382 A°. In electronic properties, the spin-polarized electronic bandstructure elucidates the semiconductor nature of the material in both spin channels, with the compound was observed to have a narrow bandgap on the spin-down configuration (0.162 EV) and bandgap on the spin-up (2.067 EV). Hence, the doped atom Cu plays a vital role in increasing the magnetic moments of the supercell, and the value of the total magnetic moment is found to be 2.99438 μB. Therefore, the compound Cu-doped CeO₂ shows a strong ferromagnetic behavior. The predicted results propose the compound could be a good candidate for spintronics applications.

Keywords: Cu-doped CeO₂, DFT, Wien2k, properties

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3416 Experiences of Online Opportunities and Risks: Examining Internet Use and Digital Literacy of Young People in Nigeria

Authors: Isah Yahaya Aliyu

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Research on Internet use has often approached beneficial uses (online opportunities) of the Internet as separate from the risky encounters (online risks) of young people online. However, empirical evidence from diverse contexts appears to increasingly support the fusion of the two sets of online activities. Hence, the current research investigates the correlation between Internet use (IU) and digital literacy (DL) with online opportunities (OP) and risks (OR), using data from a Nigerian context, where there appears a paucity of research and literature on integrating opportunities and risks in the same study. A web-based data collection method was used to administer a survey to 335 undergraduate students in Northeastern Nigeria. Underpinned to Livingstone and Helsper model, findings are largely consistent with existing literature; IU and DL influence OP (R2 = 0.791, SE = 0.265, F-Stats = 626.566, P-value <.001), equally IU and DL influence OR as well (R2 = 0.343, SE = 0.465, F-Stats = 86.671, P-value <.001). OP and OR were found to strongly correlate positively (r = .667, n = 335, p < 0.01). This study has provided buttressing evidence from a Nigerian context of the fusion of benefits and risks of the Internet among young people. It has also upheld the argument for improved literacy as strategy for minimizing risks/harm rather than restricting use. Other theoretical and policy implications of the findings have been discussed in line with local and global debates about the Internet and its attendant effects.

Keywords: digital, internet, literacy, opportunities, risks

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3415 Food Insecurity Assessment, Consumption Pattern and Implications of Integrated Food Security Phase Classification: Evidence from Sudan

Authors: Ahmed A. A. Fadol, Guangji Tong, Wlaa Mohamed

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This paper provides a comprehensive analysis of food insecurity in Sudan, focusing on consumption patterns and their implications, employing the Integrated Food Security Phase Classification (IPC) assessment framework. Years of conflict and economic instability have driven large segments of the population in Sudan into crisis levels of acute food insecurity according to the (IPC). A substantial number of people are estimated to currently face emergency conditions, with an additional sizeable portion categorized under less severe but still extreme hunger levels. In this study, we explore the multifaceted nature of food insecurity in Sudan, considering its historical, political, economic, and social dimensions. An analysis of consumption patterns and trends was conducted, taking into account cultural influences, dietary shifts, and demographic changes. Furthermore, we employ logistic regression and random forest analysis to identify significant independent variables influencing food security status in Sudan. Random forest clearly outperforms logistic regression in terms of area under curve (AUC), accuracy, precision and recall. Forward projections of the IPC for Sudan estimate that 15 million individuals are anticipated to face Crisis level (IPC Phase 3) or worse acute food insecurity conditions between October 2023 and February 2024. Of this, 60% are concentrated in Greater Darfur, Greater Kordofan, and Khartoum State, with Greater Darfur alone representing 29% of this total. These findings emphasize the urgent need for both short-term humanitarian aid and long-term strategies to address Sudan's deepening food insecurity crisis.

Keywords: food insecurity, consumption patterns, logistic regression, random forest analysis

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3414 Comparisons of Co-Seismic Gravity Changes between GRACE Observations and the Predictions from the Finite-Fault Models for the 2012 Mw = 8.6 Indian Ocean Earthquake Off-Sumatra

Authors: Armin Rahimi

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The Gravity Recovery and Climate Experiment (GRACE) has been a very successful project in determining math redistribution within the Earth system. Large deformations caused by earthquakes are in the high frequency band. Unfortunately, GRACE is only capable to provide reliable estimate at the low-to-medium frequency band for the gravitational changes. In this study, we computed the gravity changes after the 2012 Mw8.6 Indian Ocean earthquake off-Sumatra using the GRACE Level-2 monthly spherical harmonic (SH) solutions released by the University of Texas Center for Space Research (UTCSR). Moreover, we calculated gravity changes using different fault models derived from teleseismic data. The model predictions showed non-negligible discrepancies in gravity changes. However, after removing high-frequency signals, using Gaussian filtering 350 km commensurable GRACE spatial resolution, the discrepancies vanished, and the spatial patterns of total gravity changes predicted from all slip models became similar at the spatial resolution attainable by GRACE observations, and predicted-gravity changes were consistent with the GRACE-detected gravity changes. Nevertheless, the fault models, in which give different slip amplitudes, proportionally lead to different amplitude in the predicted gravity changes.

Keywords: undersea earthquake, GRACE observation, gravity change, dislocation model, slip distribution

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3413 N-Glycosylation in the Green Microalgae Chlamydomonas reinhardtii

Authors: Pierre-Louis Lucas, Corinne Loutelier-Bourhis, Narimane Mati-Baouche, Philippe Chan Tchi-Song, Patrice Lerouge, Elodie Mathieu-Rivet, Muriel Bardor

Abstract:

N-glycosylation is a post-translational modification taking place in the Endoplasmic Reticulum and the Golgi apparatus where defined glycan features are added on protein in a very specific sequence Asn-X-Thr/Ser/Cys were X can be any amino acid except proline. Because it is well-established that those N-glycans play a critical role in protein biological activity, protein half-life and that a different N-glycan structure may induce an immune response, they are very important in Biopharmaceuticals which are mainly glycoproteins bearing N-glycans. From now, most of the biopharmaceuticals are produced by mammalian cells like Chinese Hamster Ovary cells (CHO) for their N-glycosylation similar to the human, but due to the high production costs, several other species are investigated as the possible alternative system. In this purpose, the green microalgae Chlamydomonas reinhardtii was investigated as the potential production system for Biopharmaceuticals. This choice was influenced by the facts that C. reinhardtii is a well-study microalgae which is growing fast with a lot of molecular biology tools available. This organism is also producing N-glycan on its endogenous proteins. However, the analysis of the N-glycan structure of this microalgae has revealed some differences as compared to the human. Rather than in Human where the glycans are processed by key enzymes called N-acetylglucosaminyltransferase I and II (GnTI and GnTII) adding GlcNAc residue to form a GlcNAc₂Man₃GlcNAc₂ core N-glycan, C. reinhardtii lacks those two enzymes and possess a GnTI independent glycosylation pathway. Moreover, some enzymes like xylosyltransferases and methyltransferases not present in human are supposed to act on the glycans of C. reinhardtii. Furthermore, the recent structural study by mass spectrometry shows that the N-glycosylation precursor supposed to be conserved in almost all eukaryotic cells results in a linear Man₅GlcNAc₂ rather than a branched one in C. reinhardtii. In this work, we will discuss the new released MS information upon C. reinhardtii N-glycan structure and their impact on our attempt to modify the glycan in a Human manner. Two strategies will be discussed. The first one consisted in the study of Xylosyltransferase insertional mutants from the CLIP library in order to remove xyloses from the N-glycans. The second will go further in the humanization by transforming the microalgae with the exogenous gene from Toxoplasma gondii having an activity similar to GnTI and GnTII with the aim to synthesize GlcNAc₂Man₃GlcNAc₂ in C. reinhardtii.

Keywords: Chlamydomonas reinhardtii, N-glycosylation, glycosyltransferase, mass spectrometry, humanization

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3412 Comparison of Rumen Microbial Analysis Pipelines Based on 16s rRNA Gene Sequencing

Authors: Xiaoxing Ye

Abstract:

To investigate complex rumen microbial communities, 16S ribosomal RNA (rRNA) sequencing is widely used. Here, we evaluated the impact of bioinformatics pipelines on the observation of OTUs and taxonomic classification of 750 cattle rumen microbial samples by comparing three commonly used pipelines (LotuS, UPARSE, and QIIME) with Usearch. In LotuS-based analyses, 189 archaeal and 3894 bacterial OTUs were observed. The observed OTUs for the Usearch analysis were significantly larger than the LotuS results. We discovered 1495 OTUs for archaea and 92665 OTUs for bacteria using Usearch analysis. In addition, taxonomic assignments were made for the rumen microbial samples. All pipelines had consistent taxonomic annotations from the phylum to the genus level. A difference in relative abundance was calculated for all microbial levels, including Bacteroidetes (QIIME: 72.2%, Usearch: 74.09%), Firmicutes (QIIME: 18.3%, Usearch: 20.20%) for the bacterial phylum, Methanobacteriales (QIIME: 64.2%, Usearch: 45.7%) for the archaeal class, Methanobacteriaceae (QIIME: 35%, Usearch: 45.7%) and Methanomassiliicoccaceae (QIIME: 35%, Usearch: 31.13%) for archaeal family. However, the most prevalent archaeal class varied between these two annotation pipelines. The Thermoplasmata was the top class according to the QIIME annotation, whereas Methanobacteria was the top class according to Usearch.

Keywords: cattle rumen, rumen microbial, 16S rRNA gene sequencing, bioinformatics pipeline

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3411 Gender Inequalities in Depression among Palestinian Citizens in Israel

Authors: Nihaya Daoud, Adi Finkelstein

Abstract:

Depression is a major public health concern and it is estimated to be the second leading cause of morbidity in 2020. One of the most consistent findings in mental health in the Western societies is inequalities in depression between men and women. Studies on differences in depression between Arab men and women are scarce. In this paper, we use data of a countrywide study on the Arab minority in Israel to compare the prevalence of depressive symptoms between men and women and examine factors that contribute to this gender inequality in the context of Arab society. The study was conducted in 2005-2006. It included a sample of Palestinian citizens of Israel, aged 30–70. The final sample included 902 respondents (381 women and 521 men) who were interviewed face-to-face using a structured questionnaire in Arabic, before which they each signed an informed consent form. The study was approved by the Institutional Review Board at Hadassah – Hebrew University Medical Center. Results show that women had significantly higher depressive symptoms (DS) than men. In addition, while Arab women had steady rates of depressive symptoms between the ages of 40-54 and a peak at the age group of 55-59, among Arab men there was a peak almost every 10 years (more results will show in the full presentation). We assume that our findings might be attributed to the specific structural changes in the Arab society in Israel in the last decades.

Keywords: Arab men, Arab women, depression, gender inequality

Procedia PDF Downloads 232
3410 Impact of Fire on Bird Diversity in Oil Palm Plantation: Case Study in South Sumatra Province

Authors: Yanto Santosa, Windi Sugiharti

Abstract:

Fires occur annually in oil palm plantations. The objective of the study was to identify the impact of fire on bird diversity in oil palm plantations. Data of bird diversity were collected using the line transect method. Data were collected from February to March 2017. To estimate species richness, we used the Margalef index, to determine the evenness of species richness between site, we used an Evenness index, and to estimate the similarity of bird communities between different habitat, we used the Sørensen index. The result showed that the number of bird species and species richness in the post burned area was higher than those in unburned area. Different results were found for the Evenness Index, where the value was higher in unburned area that was in post burned area. These results indicate that fires did not decrease bird diversity as alleged by many parties whom stated that fires caused species extinction. Fire trigger the emerging of belowground plant and population of insects as a sources of food for the bird community. This result is consistent with several research findings in the United States and Australia that used controlled fires as one of regional management tools.

Keywords: bird, fire, index of similarity, oil palm, species diversity

Procedia PDF Downloads 232
3409 E-Bike FE Model Analysis: Connection Stiffness of Elements with Different DOFs

Authors: Lele Zhang, Hui Leng Choo, Alexander Konyukhov, Shuguang Li

Abstract:

Finite Element (FE) model of simplified e-bike structure was generated by main frame with two tiers, which consisted of pipe, mass, beam, and shell elements (pipe 289, beam188, shell 181, shell 281, combin14, link11, mass21). These elements would be introduced and demonstrated using mathematical formulas. Based on coupling theory, constrain equations was proposed. Exporting all the parameters obtained from theory part, the connection stiffness matrix of the whole e-bike structure between each of these elements was detected.

Keywords: coupling theory, stiffness matrix, e-bike, finite element model

Procedia PDF Downloads 367
3408 Coexisting Pathology of Unruptured Ectopic Pregnancy With Concurrent Ipsilateral Dermoid Cyst: A Rare Occurrence

Authors: Anne Nicole Fuentes

Abstract:

A 29 year old Gravida 1 Para 0 who presented at the hospital with a 5-week history of amenorrhea, abdominal pain and vaginal bleeding. Transvaginal ultrasound revealed 3 pathologic findings : Tuboovarian complex on the right adnexa, a complex mass indicative of an unruptured ectopic pregnancy and right ovarian new growth probably endometrioma. Pelvic laparotomy was done and histopathologic finding revealed tubal pregnancy, right and mature cystic teratoma of the right ovary. This case report demonstrates the importance of considering the coexistence of different gynecologic pathologies in the same patient and clinical importance of an accurate diagnostic evaluation.

Keywords: mature cystic teratoma, ectopic pregnancy, Tuboovarian abscess, bHCG

Procedia PDF Downloads 127
3407 Augmented Reality Using Cuboid Tracking as a Support for Early Stages of Architectural Design

Authors: Larissa Negris de Souza, Ana Regina Mizrahy Cuperschmid, Daniel de Carvalho Moreira

Abstract:

Augmented Reality (AR) alters the elaboration of the architectural project, which relates to project cognition: representation, visualization, and perception of information. Understanding these features from the earliest stages of the design can facilitate the study of relationships, zoning, and overall dimensions of the forms. This paper’s goal was to explore a new approach for information visualization during the early stages of architectural design using Augmented Reality (AR). A three-dimensional marker inspired by the Rubik’s Cube was developed, and its performance, evaluated. This investigation interwovens the acquired knowledge of traditional briefing methods and contemporary technology. We considered the concept of patterns (Alexander et al. 1977) to outline geometric forms and associations using visual programming. The Design Science Research was applied to develop the study. An SDK was used in a game engine to generate the AR app. The tool's functionality was assessed by verifying the readability and precision of the reconfigurable 3D marker. The results indicated an inconsistent response. To use AR in the early stages of architectural design the system must provide consistent information and appropriate feedback. Nevertheless, we conclude that our framework sets the ground for looking deep into AR tools for briefing design.

Keywords: augmented reality, cuboid marker, early design stages, graphic representation, patterns

Procedia PDF Downloads 87
3406 Investigation of Knitted Fabric Properties Effect on Evaporation Rate

Authors: N. S. Achour, M. Hamdaoui, S. Ben Nasrallah

Abstract:

Evaporation kinetics of water from porous knitted fabrics are studied: An experimental study of determining evaporated water mass (g) versus time (s) from different knitted fabrics was gravimetrically investigated in various atmospheric conditions. Then evaporation rates are calculated. The goal is to determine the effect of fabric composition, knit structure and yarns properties on evaporation rate. The results show that fabrics geometrical properties, such as porosity and thickness, have a significant influence on evaporated water quantities.

Keywords: evaporation rate, experimental study, geometrical properties, porous knitted fabrics

Procedia PDF Downloads 494
3405 A Review of Critical Framework Assessment Matrices for Data Analysis on Overheating in Buildings Impact

Authors: Martin Adlington, Boris Ceranic, Sally Shazhad

Abstract:

In an effort to reduce carbon emissions, changes in UK regulations, such as Part L Conservation of heat and power, dictates improved thermal insulation and enhanced air tightness. These changes were a direct response to the UK Government being fully committed to achieving its carbon targets under the Climate Change Act 2008. The goal is to reduce emissions by at least 80% by 2050. Factors such as climate change are likely to exacerbate the problem of overheating, as this phenomenon expects to increase the frequency of extreme heat events exemplified by stagnant air masses and successive high minimum overnight temperatures. However, climate change is not the only concern relevant to overheating, as research signifies, location, design, and occupation; construction type and layout can also play a part. Because of this growing problem, research shows the possibility of health effects on occupants of buildings could be an issue. Increases in temperature can perhaps have a direct impact on the human body’s ability to retain thermoregulation and therefore the effects of heat-related illnesses such as heat stroke, heat exhaustion, heat syncope and even death can be imminent. This review paper presents a comprehensive evaluation of the current literature on the causes and health effects of overheating in buildings and has examined the differing applied assessment approaches used to measure the concept. Firstly, an overview of the topic was presented followed by an examination of overheating research work from the last decade. These papers form the body of the article and are grouped into a framework matrix summarizing the source material identifying the differing methods of analysis of overheating. Cross case evaluation has identified systematic relationships between different variables within the matrix. Key areas focused on include, building types and country, occupants behavior, health effects, simulation tools, computational methods.

Keywords: overheating, climate change, thermal comfort, health

Procedia PDF Downloads 340
3404 Construction of Microbial Fuel Cells from Local Benthic Zones

Authors: Maria Luiza D. Ramiento, Maria Lissette D. Lucas

Abstract:

Electricity is said to serve as the backbone of modern technology. Considering this, electricity consumption has dynamically grown due to the continuous demand. An alternative producer of energy concerning electricity must therefore be given focus. Microbial fuel cell wholly characterizes a new method of renewable energy recovery: the direct conversion of organic matter to electricity using bacteria. Electricity is produced as fuel or new food is given to the bacteria. The study concentrated in determining the feasibility of electricity production from local benthic zones. Microbial fuel cells were constructed to harvest the possible electricity and to test the presence of electricity producing microorganisms. Soil samples were gathered from Calumpang River, Palawan Mangrove Forest, Rosario River and Batangas Port. Eleven modules were constructed for the different trials of the soil samples. These modules were made of cathode and anode chambers connected by a salt bridge. For 85 days, the harvested voltage was measured daily. No parameter is added for the first 24 days. For the next 61 days, acetic acid was included in the first and second trials of the modules. Each of the trials of the soil samples gave a positive result in electricity production.There were electricity producing microbes in local benthic zones. It is observed that the higher the organic content of the soil sample, the higher the electricity harvested from it. It is recommended to identify the specific species of the electricity-producing microorganism present in the local benthic zone. Complement experiments are encouraged like determining the kind of soil particles to test its effect on the amount electricity that can be harvested. To pursue the development of microbial fuel cells by building a closed circuit in it is also suggested.

Keywords: microbial fuel cell, benthic zone, electricity, reduction-oxidation reaction, bacteria

Procedia PDF Downloads 385