Search results for: single animal fibre fractionation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6018

Search results for: single animal fibre fractionation

5118 Mammographic Multi-View Cancer Identification Using Siamese Neural Networks

Authors: Alisher Ibragimov, Sofya Senotrusova, Aleksandra Beliaeva, Egor Ushakov, Yuri Markin

Abstract:

Mammography plays a critical role in screening for breast cancer in women, and artificial intelligence has enabled the automatic detection of diseases in medical images. Many of the current techniques used for mammogram analysis focus on a single view (mediolateral or craniocaudal view), while in clinical practice, radiologists consider multiple views of mammograms from both breasts to make a correct decision. Consequently, computer-aided diagnosis (CAD) systems could benefit from incorporating information gathered from multiple views. In this study, the introduce a method based on a Siamese neural network (SNN) model that simultaneously analyzes mammographic images from tri-view: bilateral and ipsilateral. In this way, when a decision is made on a single image of one breast, attention is also paid to two other images – a view of the same breast in a different projection and an image of the other breast as well. Consequently, the algorithm closely mimics the radiologist's practice of paying attention to the entire examination of a patient rather than to a single image. Additionally, to the best of our knowledge, this research represents the first experiments conducted using the recently released Vietnamese dataset of digital mammography (VinDr-Mammo). On an independent test set of images from this dataset, the best model achieved an AUC of 0.87 per image. Therefore, this suggests that there is a valuable automated second opinion in the interpretation of mammograms and breast cancer diagnosis, which in the future may help to alleviate the burden on radiologists and serve as an additional layer of verification.

Keywords: breast cancer, computer-aided diagnosis, deep learning, multi-view mammogram, siamese neural network

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5117 Thin-Film Nanocomposite Membrane with Single-Walled Carbon Nanotubes Axial Positioning in Support Layer for Desalination of Water

Authors: Ahmed A. Alghamdi

Abstract:

Single-walled carbon nanotubes (SWCNTs) are an outstanding material for applications in thermoelectric power generation, nanoelectronics, electrochemical energy storage, photovoltaics, and light emission. They are ultra-lightweight and possess electrical as well as thermal conductivity, flexibility, and mechanical strength. SWCNT is applicable in water treatment, brine desalination, removal of heavy metal ions associated with pollutants, and oil-water separation. Carbon nanotube (CNT) is believed to tackle the trade-off issue between permeability, selectivity, and fouling issues in membrane filtration applications. Studying these CNT structures, as well as their interconnection in nanotechnology, assists in finding the precise position to be placed for water desalination. Reverse osmosis (RO) has been used globally for desalination, resulting in purified water. Thin film composite (TFC) membranes were utilized in the RO process for desalination. The sheet thickness increases the salt rejection and decreases the water flux when CNT is utilized as a support layer to this membrane. Thus, through a temperature-induced phase separation technique (TIPS), axially aligned SWCNT (AASWCNT) is fabricated, and its use enhances the salt rejection and water flux at short reaction times with a modified procedure. An evaluation was conducted and analogized with prior works in the literature, which exhibited that the prepared TFC membrane showed a better outcome.

Keywords: single-walled carbon nanotubes, thin film composite, axially aligned swcnt, temperature induced phase separation technique, reverse osmosis

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5116 Multi-Sensor Target Tracking Using Ensemble Learning

Authors: Bhekisipho Twala, Mantepu Masetshaba, Ramapulana Nkoana

Abstract:

Multiple classifier systems combine several individual classifiers to deliver a final classification decision. However, an increasingly controversial question is whether such systems can outperform the single best classifier, and if so, what form of multiple classifiers system yields the most significant benefit. Also, multi-target tracking detection using multiple sensors is an important research field in mobile techniques and military applications. In this paper, several multiple classifiers systems are evaluated in terms of their ability to predict a system’s failure or success for multi-sensor target tracking tasks. The Bristol Eden project dataset is utilised for this task. Experimental and simulation results show that the human activity identification system can fulfill requirements of target tracking due to improved sensors classification performances with multiple classifier systems constructed using boosting achieving higher accuracy rates.

Keywords: single classifier, ensemble learning, multi-target tracking, multiple classifiers

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5115 Numerical Investigation on Load Bearing Capacity of Pervious Concrete Piles as an Alternative to Granular Columns

Authors: Ashkan Shafee, Masoud Ghodrati, Ahmad Fahimifar

Abstract:

Pervious concrete combines considerable permeability with adequate strength, which makes it very beneficial in pavement construction and also in ground improvement projects. In this paper, a single pervious concrete pile subjected to vertical and lateral loading is analysed using a verified three dimensional finite element code. A parametric study was carried out in order to investigate load bearing capacity of a single unreinforced pervious concrete pile in saturated soft soil and also gain insight into the failure mechanism of this rather new soil improvement technique. The results show that concrete damaged plasticity constitutive model can perfectly simulate the highly brittle nature of the pervious concrete material and considering the computed vertical and horizontal load bearing capacities, some suggestions have been made for ground improvement projects.

Keywords: concrete damaged plasticity, ground improvement, load-bearing capacity, pervious concrete pile

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5114 The Effect of Backing Layer on Adhesion Properties of Single Layer Ketoprofen Transdermal Drug Delivery System

Authors: Maryam Hamedanlou, Shahla Hajializadeh

Abstract:

The transdermal drug delivery system is one of the types of novel drug delivery system that the drug is absorbed into the skin. The major considerations for designing and producing transdermal patch are small size, suitable drug release and good adhering. In this study, drug-in-adhesive transdermal patch contained non-steroidal anti-inflammatory ketoprofen is prepared. Also, the effect of non-woven fabric and plastic backing layers on adhesion properties is assessed. The results of the test, demonstrated the use of plastic backing layer increases tack and peel rather than non-woven fabric type. The balance tack with plastic backing layer patch is 6.7 (N/mm2), and the fabric one is 3.8 (N/mm2), and their peel is 9.2 (N/25mm) and 8.3 (N/25mm) by arrangement.

Keywords: transdermal drug delivery system, single layer patch of ketoprofen, plastic layer, fabric backing layer

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5113 Mechanical Testing of Composite Materials for Monocoque Design in Formula Student Car

Authors: Erik Vassøy Olsen, Hirpa G. Lemu

Abstract:

Inspired by the Formula-1 competition, IMechE (Institute of Mechanical Engineers) and Formula SAE (Society of Mechanical Engineers) organize annual competitions for University and College students worldwide to compete with a single-seat race car they have designed and built. The design of the chassis or the frame is a key component of the competition because the weight and stiffness properties are directly related with the performance of the car and the safety of the driver. In addition, a reduced weight of the chassis has a direct influence on the design of other components in the car. Among others, it improves the power to weight ratio and the aerodynamic performance. As the power output of the engine or the battery installed in the car is limited to 80 kW, increasing the power to weight ratio demands reduction of the weight of the chassis, which represents the major part of the weight of the car. In order to reduce the weight of the car, ION Racing team from the University of Stavanger, Norway, opted for a monocoque design. To ensure fulfilment of the above-mentioned requirements of the chassis, the monocoque design should provide sufficient torsional stiffness and absorb the impact energy in case of a possible collision. The study reported in this article is based on the requirements for Formula Student competition. As part of this study, diverse mechanical tests were conducted to determine the mechanical properties and performances of the monocoque design. Upon a comprehensive theoretical study of the mechanical properties of sandwich composite materials and the requirements of monocoque design in the competition rules, diverse tests were conducted including 3-point bending test, perimeter shear test and test for absorbed energy. The test panels were homemade and prepared with an equivalent size of the side impact zone of the monocoque, i.e. 275 mm x 500 mm so that the obtained results from the tests can be representative. Different layups of the test panels with identical core material and the same number of layers of carbon fibre were tested and compared. Influence of the core material thickness was also studied. Furthermore, analytical calculations and numerical analysis were conducted to check compliance to the stated rules for Structural Equivalency with steel grade SAE/AISI 1010. The test results were also compared with calculated results with respect to bending and torsional stiffness, energy absorption, buckling, etc. The obtained results demonstrate that the material composition and strength of the composite material selected for the monocoque design has equivalent structural properties as a welded frame and thus comply with the competition requirements. The developed analytical calculation algorithms and relations will be useful for future monocoque designs with different lay-ups and compositions.

Keywords: composite material, Formula student, ION racing, monocoque design, structural equivalence

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5112 Durability of Lime Treated Soil Reinforced by Natural Fibre under Bending Force

Authors: Vivi Anggraini, Afshin Asadi, Bujang B. K. Huat

Abstract:

Earth structures constructed of marine clay soils have tendency to crack. In order to improve the flexural strength and brittleness, a technique of mixing short fibers is introduced to the soil lime mixture. Coir fiber was used in this study as reinforcing elements. An experimental investigation consisting primarily of flexural tensile tests was conducted to examine the influence of coir fibers on the flexural behaviour of the reinforced soils. The test results demonstrated that the coir fibers were effective in improving the flexural strength and young’s modulus of all soils were examined and ductility after peak strength for reinforced marine clay soil was treated by lime. 5% lime treated soil and 1% coir fiber reinforced soil specimen’s demonstrated good strength and durability when submerged in water and retained 45% of their air-cured strengths.

Keywords: flexural strength, durabilty, lime, coir fibers, bending force, ductility

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5111 Permanent Magnet Synchronous Generator: Unsymmetrical Point Operation

Authors: P. Pistelok

Abstract:

The article presents the concept of an electromagnetic circuit generator with permanent magnets mounted on the surface rotor core designed for single phase work. Computation field-circuit model was shown. The spectrum of time course of voltages in the idle work was presented. The cross section with graphically presentation of magnetic induction in particular parts of electromagnetic circuits was presented. Distribution of magnetic induction at the rated load point for each phase were shown. The time course of voltages and currents for each phases for rated power were displayed. An analysis of laboratory results and measurement of load characteristics of the generator was discussed. The work deals with three electromagnetic circuits of generators with permanent magnet where output voltage characteristics versus rated power were expressed.

Keywords: permanent magnet generator, permanent magnets, vibration, course of torque, single phase work, asymmetrical three phase work

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5110 The Short-Term Stress Indicators in Home and Experimental Dogs

Authors: Madara Nikolajenko, Jevgenija Kondratjeva

Abstract:

Stress is a response of the body to physical or psychological environmental stressors. Cortisol level in blood serum is determined as the main indicator of stress, but the blood collection, the animal preparation and other activities can cause unpleasant conditions and induce increase of these hormones. Therefore, less invasive methods are searched to determine stress hormone levels, for example, by measuring the cortisol level saliva. The aim of the study is to find out the changes of stress hormones in blood and saliva in home and experimental dogs in simulated short-term stress conditions. The study included clinically healthy experimental beagle dogs (n=6) and clinically healthy home American Staffordshire terriers (n=6). The animals were let into a fenced area to adapt. Loud drum sounds (in cooperation with 'Andžeja Grauda drum school') were used as a stressor. Blood serum samples were taken for sodium, potassium, glucose and cortisol level determination and saliva samples for cortisol determination only. Control parameters were taken immediately before the start of the stressor, and next samples were taken immediately after the stress. The last measurements were taken two hours after the stress. Electrolyte levels in blood serum were determined using direction selective electrode method (ILab Aries analyzer) and cortisol in blood serum and saliva using electrochemical luminescence method (Roche Diagnostics). Blood glucose level was measured with glucometer (ACCU-CHECK Active test strips). Cortisol level in the blood increased immediately after the stress in all home dogs (P < 0,05), but only in 33% (P < 0,05) of the experimental dogs. After two hours the measurement decreased in 83% (P < 0,05) of home dogs (in 50% returning to the control point) and in 83% (P < 0,05) of the experimental dogs. Cortisol in saliva immediately after the stress increased in 50% (P > 0,05) of home dogs and in 33% (P > 0,05) of the experimental dogs. After two hours in 83% (P > 0,05) of the home animals, the measurements decreased, only in 17% of the experimental dogs it decreased as well, while in 49% measurement was undetectable due to the lack of material. Blood sodium, potassium, and glucose measurements did not show any significant changes. The combination of short-term stress indicators, when, after the stressor, all indicators should immediately increase and decrease after two hours, confirmed in none of the animals. Therefore the authors can conclude that each animal responds to a stressful situation with different physiological mechanisms and hormonal activity. Cortisol level in saliva and blood is released with the different speed and is not an objective indicator of acute stress.

Keywords: animal behaivor, cortisol, short-term stress, stress indicators

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5109 Identification and Characterisation of Oil Sludge Degrading Bacteria Isolated from Compost

Authors: O. Ubani, H. I. Atagana, M. S. Thantsha, R. Adeleke

Abstract:

The oil sludge components (polycyclic aromatic hydrocarbons, PAHs) have been found to be cytotoxic, mutagenic and potentially carcinogenic and microorganisms such as bacteria and fungi can degrade the oil sludge to less toxic compounds such as carbon dioxide, water and salts. In the present study, we isolated different bacteria with PAH-degrading potentials from the co-composting of oil sludge and different animal manure. These bacteria were isolated on the mineral base medium and mineral salt agar plates as a growth control. A total of 31 morphologically distinct isolates were carefully selected from 5 different compost treatments for identification using polymerase chain reaction (PCR) of the 16S rDNA gene with specific primers (16S-P1 PCR and 16S-P2 PCR). The amplicons were sequenced and sequences were compared with the known nucleotides from the gene bank database. The phylogenetical analyses of the isolates showed that they belong to 3 different clades namely Firmicutes, Proteobacteria and Actinobacteria. These bacteria identified were closely related to genera Bacillus, Arthrobacter, Staphylococcus, Brevibacterium, Variovorax, Paenibacillus, Ralstonia and Geobacillus species. The results showed that Bacillus species were more dominant in all treated compost piles. Based on their characteristics these bacterial isolates have high potential to utilise PAHs of different molecular weights as carbon and energy sources. These identified bacteria are of special significance in their capacity to emulsify the PAHs and their ability to utilize them. Thus, they could be potentially useful for bioremediation of oil sludge and composting processes.

Keywords: bioaugmentation, biodegradation, bioremediation, composting, oil sludge, PAHs, animal manures

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5108 Critical Buckling Load of Carbon Nanotube with Non-Local Timoshenko Beam Using the Differential Transform Method

Authors: Tayeb Bensattalah, Mohamed Zidour, Mohamed Ait Amar Meziane, Tahar Hassaine Daouadji, Abdelouahed Tounsi

Abstract:

In this paper, the Differential Transform Method (DTM) is employed to predict and to analysis the non-local critical buckling loads of carbon nanotubes with various end conditions and the non-local Timoshenko beam described by single differential equation. The equation differential of buckling of the nanobeams is derived via a non-local theory and the solution for non-local critical buckling loads is finding by the DTM. The DTM is introduced briefly. It can easily be applied to linear or nonlinear problems and it reduces the size of computational work. Influence of boundary conditions, the chirality of carbon nanotube and aspect ratio on non-local critical buckling loads are studied and discussed. Effects of nonlocal parameter, ratios L/d, the chirality of single-walled carbon nanotube, as well as the boundary conditions on buckling of CNT are investigated.

Keywords: boundary conditions, buckling, non-local, differential transform method

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5107 Beneficiation of Pulp and Paper Mill Sludge for the Generation of Single Cell Protein for Fish Farming

Authors: Lucretia Ramnath

Abstract:

Fishmeal is extensively used for fish farming but is an expensive fish feed ingredient. A cheaper alternate to fishmeal is single cell protein (SCP) which can be cultivated on fermentable sugars recovered from organic waste streams such as pulp and paper mill sludge (PPMS). PPMS has a high cellulose content, thus is suitable for glucose recovery through enzymatic hydrolysis but is hampered by lignin and ash. To render PPMS amenable for enzymatic hydrolysis, the PPMS waspre-treated to produce a glucose-rich hydrolysate which served as a feed stock for the production of fungal SCP. The PPMS used in this study had the following composition: 72.77% carbohydrates, 8.6% lignin, and 18.63% ash. The pre-treatments had no significant effect on lignin composition but had a substantial effect on carbohydrate and ash content. Enzymatic hydrolysis of screened PPMS was previously optimized through response surface methodology (RSM) and 2-factorial design. The optimized protocol resulted in a hydrolysate containing 46.1 g/L of glucose, of which 86% was recovered after downstream processing by passing through a 100-mesh sieve (38 µm pore size). Vogel’s medium supplemented with 10 g/L hydrolysate successfully supported the growth of Fusarium venenatum, conducted using standard growth conditions; pH 6, 200 rpm, 2.88 g/L ammonium phosphate, 25°C. A maximum F. venenatum biomass of 45 g/L was produced with a yield coefficient of 4.67. Pulp and paper mill sludge hydrolysate contained approximately five times more glucose than what was needed for SCP production and served as a suitable carbon source. We have shown that PPMS can be successfully beneficiated for SCP production.

Keywords: pulp and paper waste, fungi, single cell protein, hydrolysate

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5106 Dynamic Measurement System Modeling with Machine Learning Algorithms

Authors: Changqiao Wu, Guoqing Ding, Xin Chen

Abstract:

In this paper, ways of modeling dynamic measurement systems are discussed. Specially, for linear system with single-input single-output, it could be modeled with shallow neural network. Then, gradient based optimization algorithms are used for searching the proper coefficients. Besides, method with normal equation and second order gradient descent are proposed to accelerate the modeling process, and ways of better gradient estimation are discussed. It shows that the mathematical essence of the learning objective is maximum likelihood with noises under Gaussian distribution. For conventional gradient descent, the mini-batch learning and gradient with momentum contribute to faster convergence and enhance model ability. Lastly, experimental results proved the effectiveness of second order gradient descent algorithm, and indicated that optimization with normal equation was the most suitable for linear dynamic models.

Keywords: dynamic system modeling, neural network, normal equation, second order gradient descent

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5105 Influence of ABCB1 2677G > T Single Nucleotide Polymorphism on Warfarin Maintenance Therapy among Patients with Prosthetic Heart Valve

Authors: M. G. Gopisankar, A. Surendiran, M. Hemachandren

Abstract:

The dose requirement of warfarin to achieve target INR range varies in patients with prosthetic heart valve. This variation in is affected by both genetic and non-genetic factors. Earlier studies have identified role of CYP2C9 and VKORC1 genetic polymorphisms on warfarin dose requirement. Warfarin being a substrate for drug transporter, P-glycoprotein coded by ABCB1 gene, may also be influenced by its genetic polymorphisms. This study was aimed to study the effect of single nucleotide polymorphism (SNP), ABCB1 2677G > T on warfarin maintenance dose requirement in patients with steady-state International Normalized Ratio (INR). The median dose requirement was significantly different between the genotype groups GG vs. GT (35 ± 20; 42.5 ± 18, p < 0.05), GG vs. TT (35 ± 20; 41.25 ± 25, p<0.05). There was no significant difference between GT vs. TT. In conclusion, patients with variant allele require a higher weekly maintenance dose of warfarin compared to patients without variant allele.

Keywords: warfarin pharamcogenetics, pharmacogenomics of warfarin, ABCB1 and warfarin, pglycoprotein and warfarin

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5104 Settlement Performance of Soft Clay Reinforced with Granular Columns

Authors: Muneerah Jeludin, V. Sivakumar

Abstract:

Numerous laboratory-based research studies on the behavior of ground improved with granular columns with respect to bearing capacity have been well-documented. However, information on its settlement performance is still scarce. Laboratory model study on the settlement behavior of soft clay reinforced with granular columns was conducted and results are presented. The investigation uses a soft kaolin clay sample of 300 mm in diameter and 400 mm in length. The clay samples were reinforced with single and multiple granular columns of various lengths using the displacement and replacement installation method. The results indicated that that no settlement reduction was achieved for a short single floating column. The settlement reduction factors reported for L/d ratios of 5.0, 7.5 and 10.0 are in the range of 1 to 2. The findings obtained in this research showed that the reduction factors are considerably less and that load-sharing mechanism between columns and surrounding clay is complex, particularly for column groups and is affected by other factors such as negative skin friction.

Keywords: ground improvement, model test, reinforced soil, settlement

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5103 Comparison Between Two Techniques (Extended Source to Surface Distance & Field Alignment) Of Craniospinal Irradiation (CSI) In the Eclipse Treatment Planning System

Authors: Naima Jannat, Ariful Islam, Sharafat Hossain

Abstract:

Due to the involvement of the large target volume, Craniospinal Irradiation makes it challenging to achieve a uniform dose, and it requires different isocenters. This isocentric junction needs to shift after every five fractions to overcome the possibility of hot and cold spots. This study aims to evaluate the Planning Target Volume coverage & sparing Organ at Risk between two techniques and shows that the Field Alignment Technique does not need replanning and resetting. Planning method for Craniospinal Irradiation by Eclipse treatment planning system Field Alignment and Extended Source to Surface Distance technique was developed where 36 Gy in 20 Fraction at the rate of 1.8 Gy was prescribed. The patient was immobilized in the prone position. In the Field Alignment technique, the plan consists of half beam blocked parallel opposed cranium and a single posterior cervicospine field was developed by sharing the same isocenter, which obviates divergence matching. Further, a single field was created to treat the remaining lumbosacral spine. Matching between the inferior diverging edge of the cervicospine field and the superior diverging edge of a lumbosacral field, the field alignment option was used, which automatically matches the field edge divergence as per the field alignment rule in Eclipse Treatment Planning System where the couch was set to 2700. In the Extended Source to Surface Distance technique, two parallel opposed fields were created for the cranium, and a single posterior cervicospine field was created where the Source to Surface Distance was from 120-140 cm. Dose Volume Histograms were obtained for each organ contoured and for each technique used. In all, the patient’s maximum dose to Planning Target Volume is higher for the Extended Source to Surface Distance technique to Field Alignment technique. The dose to all surrounding structures was increased with the use of a single Extended Source to Surface Distance when compared to the Field Alignment technique. The average mean dose to Eye, Brain Steam, Kidney, Oesophagus, Heart, Liver, Lung, and Ovaries were respectively (58% & 60 %), (103% & 98%), (13% & 15%), (10% & 63%), (12% & 16%), (33% & 30%), (14% & 18%), (69% & 61%) for Field Alignment and Extended Source to Surface Distance technique. However, the clinical target volume at the spine junction site received a less homogeneous dose with the Field Alignment technique as compared to Extended Source to Surface Distance. We conclude that, although the use of a single field Extended Source to Surface Distance delivered a more homogenous, but its maximum dose is higher than the Field Alignment technique. Also, a huge advantage of the Field Alignment technique for Craniospinal Irradiation is that it doesn’t need replanning and resetting up of patients after every five fractions and 95% prescribed dose was received by more than 95% of the Planning Target Volume in all the plane with the acceptable hot spot.

Keywords: craniospinalirradiation, cranium, cervicospine, immobilize, lumbosacral spine

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5102 Mapping of Textile Waste Generation across the Value Chains Operating in the Textile Industry

Authors: Veena Nair, Srikanth Prakash, Mayuri Wijayasundara

Abstract:

Globally, the textile industry is a key contributor to the generation of solid waste which gets landfilled. Textile waste generation generally occurs in three stages, namely: producer waste, pre-consumer waste, and post-consumer waste. However, the different processes adopted in textile material extraction, manufacturing, and use have their respective impact in terms of the quantity of waste being diverted to landfills. The study is focused on assessing the value chains of the two most common textile fibres: cotton and polyester, catering to a broad categories of apparel products. This study attempts to identify and evaluate the key processes adopted by the textile industry at each of the stages in their value chain in terms of waste generation. The different processes identified in each of the stages in the textile value chains are mapped to their respective contribution in generating fibre waste which eventually gets diverted to landfill. The results of the study are beneficial for the overall industry in terms of improving the traceability of waste in the value chains and the selection of processes and behaviours facilitating the reduction of environmental impacts associated with landfills.

Keywords: textile waste, textile value chains, landfill waste, waste mapping

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5101 Single-Inductor Multi-Output Converters with Four-Level Output Voltages

Authors: Yasunori Kobori, Murong Li, Feng Zhao, Shu Wu, Nobukazu Takai, Haruo Kobayashi

Abstract:

This paper proposes an electrolytic capacitor-less transformer-less AC-DC LED driver with a current ripple canceller. The proposed LED driver includes a diode bridge, a buck-boost converter, a negative feedback controller and a current ripple cancellation circuit. The current ripple canceller works as a bi-directional current converter using a sub-inductor, a sub-capacitor and two switches for controlling current flow. LED voltage is controlled in order to regulate LED current by the negative feedback controller using a current sense resistor. There are two capacitors with capacitance of 5 uF. We describe circuit topologies, operation principles and simulation results for our proposed circuit. In addition, we show the line regulation for input voltage variation from 85V to 130V. The output voltage ripple is 2V and the LED current ripple is 65 mA which is less than 20% of the average of LED current of 350 mA.

Keywords: DC-DC buck converter, four-level output voltage, single inductor multi output (SIMO), switching converter

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5100 Acoustic and Thermal Insulating Materials Based on Natural Fibres Used in Floor Construction

Authors: Jitka Hroudova, Jiri Zach

Abstract:

The majority of contemporary insulation materials commonly used in the building industry is made from non-renewable raw materials; furthermore, their production often brings high energy costs. A long-term trend as far as sustainable development is concerned has been the reduction of energy and material demands of building material production. One of the solutions is the possibility of using easily renewable natural raw material sources which are considerably more ecological and their production is mostly less energy-consuming compared to the production of normal insulations (mineral wool, polystyrene). The paper describes the results of research focused on the development of thermal and acoustic insulation materials based on natural fibres intended for floor constructions. Given the characteristic open porosity of natural fibre materials, the hygrothermal behaviour of the developed materials was studied. Especially the influence of relative humidity and temperature on thermal insulation properties was observed.

Keywords: Green thermal and acoustic insulating materials, natural fibres, technical hemp, flax, floor construction

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5099 The Effectiveness of Video Modeling Procedures on Request an Item Behavior Children with Autism Spectrum Disorders

Authors: Melih Cattik

Abstract:

The present study investigate effectiveness of video modeling procedures on request an item behavior of children with ASD. Two male and a female children with ASD participated in the study. A multiple baseline across participant single-subject design was used to evaluate the effects of the video modeling procedures on request an item behavior. During baseline, no prompts were presented to participants. In the intervention phase, the teacher gave video model to the participant and than created opportunity for request an item to him/her. When the first participant reached to criterion, the second participant began intervention. This procedure continued till all participants completed intervention. Finally, all three participants learned to request an item behavior. Based upon findings of this study, it will make suggestions to future researches.

Keywords: autism spectrum disorders, video modeling procedures, request an item behavior, single subject design

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5098 Agricultural Mechanization for Transformation

Authors: Lawrence Gumbe

Abstract:

Kenya Vision 2030 is the country's programme for transformation covering the period 2008 to 2030. Its objective is to help transform Kenya into a newly industrializing, middle-income, exceeding US$10000, country providing a high quality of life to all its citizens by 2030, in a clean and secure environment. Increased agricultural and production and productivity is crucial for the realization of Vision 2030. Mechanization of agriculture in order to achieve greater yields is the only way to achieve these objectives. There are contending groups and views on the strategy for agricultural mechanization. The first group are those who oppose the widespread adoption of advanced technologies (mostly internal combustion engines and tractors) in agricultural mechanization as entirely inappropriate in most situations in developing countries. This group argues that mechanically powered -agricultural mechanization often leads to displacement of labour and hence increased unemployment, and this results in a host of other socio-economic problems, amongst them, rural-urban migration, inequitable distribution of wealth and in many cases an increase in absolute poverty, balance of payments due to the need to import machinery, fuel and sometimes technical assistance to manage them. The second group comprises of those who view the use of the improved hand tools and animal powered technology as transitional step between the most rudimentary step in technological development (characterized by entire reliance on human muscle power) and the advanced technologies (characterized 'by reliance on tractors and other machinery). The third group comprises those who regard these intermediate technologies (ie. improved hand tools and draught animal technology in agriculture) as a ‘delaying’ tactic and they advocate the use of mechanical technologies as-the most appropriate. This group argues that alternatives to the mechanical technologies do not just exist as a practical matter, or, if they are available, they are inefficient and they cannot be compared to the mechanical technologies in terms of economics and productivity. The fourth group advocates a compromise between groups two and third above. This group views the improved hand tools and draught animal technology as more of an 18th century technology and the modem tractor and combine harvester as too advanced for developing countries. This group has been busy designing an ‘intermediate’, ‘appropriate’, ‘mini’, ‘micro’ tractor for use by farmers in developing countries. This paper analyses and concludes on the different agricultural mechanization strategies available to Kenya and other third world countries

Keywords: agriculture, mechanazation, transformation, industrialization

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5097 Air Pollution: The Journey from Single Particle Characterization to in vitro Fate

Authors: S. Potgieter-Vermaak, N. Bain, A. Brown, K. Shaw

Abstract:

It is well-known from public news media that air pollution is a health hazard and is responsible for early deaths. The quantification of the relationship between air quality and health is a probing question not easily answered. It is known that airborne particulate matter (APM) <2.5µm deposits in the tracheal and alveoli zones and our research probes the possibility of quantifying pulmonary injury by linking reactive oxygen species (ROS) in these particles to DNA damage. Currently, APM mass concentration is linked to early deaths and limited studies probe the influence of other properties on human health. To predict the full extent and type of impact, particles need to be characterised for chemical composition and structure. APMs are routinely analysed for their bulk composition, but of late analysis on a micro level probing single particle character, using micro-analytical techniques, are considered. The latter, single particle analysis (SPA), permits one to obtain detailed information on chemical character from nano- to micron-sized particles. This paper aims to provide a snapshot of studies using data obtained from chemical characterisation and its link with in-vitro studies to inform on personal health risks. For this purpose, two studies will be compared, namely, the bioaccessibility of the inhalable fraction of urban road dust versus total suspended solids (TSP) collected in the same urban environment. The significant influence of metals such as Cu and Fe in TSP on DNA damage is illustrated. The speciation of Hg (determined by SPA) in different urban environments proved to dictate its bioaccessibility in artificial lung fluids rather than its concentration.

Keywords: air pollution, human health, in-vitro studies, particulate matter

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5096 Intrathecal: Not Intravenous Administration of Evans Blue Reduces Pain Behavior in Neuropathic Rats

Authors: Kun Hua O., Dong Woon Kim, Won Hyung Lee

Abstract:

Introduction: Neuropathic pain induced by spinal or peripheral nerve injury is highly resistant to common painkillers, nerve blocks, and other pain management approaches. Recently, several new therapeutic drug candidates have been developed to control neuropathic pain. In this study, we used the spinal nerve L5 ligation (SNL) model to investigate the ability of intrathecal or intravenous Evans blue to decrease pain behavior and to study the relationship between Evans blue and the neural structure of pain transmission. Method: Neuropathic pain (allodynia) of the left hind paw was induced by unilateral SNL in Sprague-Dawley rats(n=10) in each group. Evans blue (5, 15, 50μg/10μl) or phosphate buffer saline(PBS,10μl) was injected intrathecally at 3days post-ligation or intravenously(1mg/200 μl) 3days and 5days post-ligation . Mechanical sensitivity was assessed using Von Frey filaments at 3 days post-ligation and at 2 hours, days 1, 2, 3, 5,7 after intrathecal Evans blue injection, and on days 2, 4, 7, and 11 at 14 days after intravenous injection. In the intrathecal group, microglia and glutaminergic neurons in the dorsal horn and VNUT(vesicular nucleotide transporter) in the dorsal root ganglia were tested to evaluate co-staining with Evans blue. The experimental procedures were performed in accordance with the animal care guideline of the Korean Academy of Medical Science(Animal ethic committee of Chungnam National University Hospital: CNUH-014-A0005-1). Results: Tight ligation of the L5 spinal nerve induced allodynia in the left hind paw 3 days post-ligation. Intrathecal Evans blue most significantly(P<0.001) alleviated allodynia at 2 days after intrathecal, but not an intravenous injection. Glutaminergic neurons in the dorsal horn and VNUT in the dorsal root ganglia were co-stained with Evans blue. On the other hand, microglia in the dorsal horn were partially co-stained with Evans blue. Conclusion: We confirmed that Evans blue might have an analgesic effect through the central nervous system, not another system in neuropathic pain of the SNL animal model. These results suggest Evans blue may be a potential new drug for the treatment of chronic pain. This research was supported by the National Research Foundation of Korea (NRF-2020R1A2C100757512), funded by the Ministry of Education.

Keywords: neuropathic pain, Evas blue, intrathecal, intravenous

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5095 Comparative and Combined Toxicity of NiO and Mn₃O₄ Nanoparticles as Assessed in vitro and in vivo

Authors: Ilzira A. Minigalieva, Tatiana V. Bushueva, Eleonore Frohlich, Vladimir Panov, Ekaterina Shishkina, Boris A. Katsnelson

Abstract:

Background: The overwhelming majority of the experimental studies in the field of metal nanotoxicology have been performed on cultures of established cell lines, with very few researchers focusing on animal experiments, while a juxtaposition of conclusions inferred from these two types of research is blatantly lacking. The least studied aspect of this problem relates to characterizing and predicting the combined toxicity of metallic nanoparticles. Methods: Comparative and combined toxic effects of purposefully prepared spherical NiO and Mn₃O₄ nanoparticles (mean diameters 16.7 ± 8.2 nm and 18.4 ± 5.4 nm respectively) were estimated on cultures of human cell lines: MRC-5 fibroblasts, THP-1 monocytes, SY-SY5Y neuroblastoma cells, as well as on the latter two lines differentiated to macrophages and neurons, respectively. The combined cytotoxicity was mathematically modeled using the response surface methodology. Results: The comparative assessment of the studied NPs unspecific toxicity previously obtained in vivo was satisfactorily reproduced by the present in vitro tests. However, with respect to manganese-specific brain damage which had been demonstrated by us in animal experiment with the same NPs, the testing on neuronall cell culture showed only a certain enhancing effect of Mn₃O₄-NPs on the toxic action of NiO-NPs, while the role of the latter prevailed. Conclusion: From the point of view of the preventive toxicology, the experimental modeling of metallic NPs combined toxicity on cell cultures can give non-reliable predictions of the in vivo action’s effects.

Keywords: manganese oxide, nickel oxide, nanoparticles, in vitro toxicity

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5094 Effect of Citrulline on the Physical Performance of a Soccer-Specific Exercises in Adult Professional Soccer Players

Authors: Bezuglov Eduard, Ryland Morgans, Talibov Oleg, Kalinin Evgeny, Butovsky Mikhail, Savin Evgeny, Tzgoev Eduard, Artemii Lazarev, Bekzhan Pirmakhanov, Anthony C. Hackney

Abstract:

Currently, there is conflicting evidence regarding the efficacy of citrulline for physical performance and post-exercise recovery. Moreover, the vast majority of studies conducted used physically active volunteers from the general population and heterogeneous exercise protocols that are not specific to most sports. A single use of citrulline, regardless of the dose, will not have a significant effect on physical performance and post-exercise recovery in highly trained soccer players performing sport-specific exercises at maximum intensity. To evaluate the effectiveness of a single administration of citrulline at various doses in adult male professional soccer players performing sport-specific exercise at maximum intensity. A randomized, double-blind, placebo-controlled study analyzing eighteen soccer players from the top divisions of several European countries. The participants were randomized into three groups of six and performed a field-based soccer-specific test at 115% VO2max for 18-minutes. Comparative analysis of the cardiovascular system, physical activity, subjective perceived fatigue and post-exercise recovery was conducted. There were no statistically significant differences in more than one analyzed parameter. A single application of 3 to 6 grams of citrulline does not affect physical performance, subjective feeling of fatigue and post-exercise recovery in adult professional soccer players who have performed a sport-specific test. Currently, citrulline cannot be recommended for use as a supplement in adult professional soccer players

Keywords: citrulline, performance, recovery, soccer players

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5093 First Principle-Based Dft and Microkinetic Simulation of Co-Conversion of Carbon Dioxide and Methane on Single Iridium Atom Doped Hematite with Surface Oxygen Defect

Authors: Kefale W. Yizengaw, Delele Worku Ayele, Jyh-Chiang Jiang

Abstract:

The catalytic co-conversion of CO₂ and CH₄ to value-added compounds has become one of the promising approaches to addressing global climate change by having valuable fossil fuels. Thedirect co-conversion of CO₂ and CH₄ to value-added compounds is attractive but tremendously challenging because of both molecules' thermodynamic stability and kinetic inertness. In the present study, a single iridium atom doped and a single oxygen atom defect hematite (110)surface model catalyst, which can comprehend direct C–O coupling based on simultaneous activation of CO2 and CH4 was studied using density functional theory plus U (DFT + U)calculations. The presence of dual active sites on the Ir/Fe₂O₃(110)-OV surface catalyst enablesCO₂ activation on the Ir site and CH₄ activation at the defect site. The electron analysis for the theco-adsorption of CO₂ and CH₄ deals with the electron redistribution on the surface and clearly shows the synergistic effect for simultaneous CO₂ and CH₄ activation on Ir/α- Fe₂O₃(110)-OVsurface. The microkinetic analysis shows that the dissociation of CH4 to CH3 * and H* plays an excellent role in the C–O coupling. The coverage analysis for the intermediate products of the microkinetic simulation results indicates that C–O coupling is the reaction limiting step. Finally, after the CH₃O* intermediate product species is produced, the radical hydrogen species spontaneously diffuse to the CH3O* intermediate product to form methanol at around 490 [K]. The present work provides mechanistic and kinetic insights into the direct C–O coupling of CO₂and CH₄, which could help design more-efficient catalysts.

Keywords: co-conversion, C–O coupling, doping, oxygen vacancy, microkinetic

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5092 Gas Permeation Behavior of Single and Mixed Gas Components Using an Asymmetric Ceramic Membrane

Authors: Ngozi Claribelle Nwogu, Mohammed Nasir Kajama, Godson Osueke, Edward Gobina

Abstract:

A unique sol–gel dip-coating process to form an asymmetric silica membrane with improved membrane performance and reproducibility has been reported. First, we deposited repeatedly a silica solution on top of a commercial alumina membrane support to improve its structural make up. The coated membrane is further processed under clean room conditions to avoid dust impurity and subsequent drying in an oven for high thermal, chemical and physical stability. The resulting asymmetric membrane exhibits a gradual change in the membrane layer thickness. Compared to a single-layer process using only the membrane support, the dual-layer process improves both flux and selectivity. For the scientifically significant difficulties of natural gas purification, collective CO2, CH4 and H2 gas fluxes and separation factors obtained gave reasonably excellent values. In addition, the membrane selectively separated hydrogen as demonstrated by a high concentration of hydrogen recovery.

Keywords: gas permeation, silica membrane, separation factor, membrane layer thickness

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5091 Analytical Downlink Effective SINR Evaluation in LTE Networks

Authors: Marwane Ben Hcine, Ridha Bouallegue

Abstract:

The aim of this work is to provide an original analytical framework for downlink effective SINR evaluation in LTE networks. The classical single carrier SINR performance evaluation is extended to multi-carrier systems operating over frequency selective channels. Extension is achieved by expressing the link outage probability in terms of the statistics of the effective SINR. For effective SINR computation, the exponential effective SINR mapping (EESM) method is used on this work. Closed-form expression for the link outage probability is achieved assuming a log skew normal approximation for single carrier case. Then we rely on the lognormal approximation to express the exponential effective SINR distribution as a function of the mean and standard deviation of the SINR of a generic subcarrier. Achieved formulas is easily computable and can be obtained for a user equipment (UE) located at any distance from its serving eNodeB. Simulations show that the proposed framework provides results with accuracy within 0.5 dB.

Keywords: LTE, OFDMA, effective SINR, log skew normal approximation

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5090 The Use of Vasopressin in the Management of Severe Traumatic Brain Injury: A Narrative Review

Authors: Nicole Selvi Hill, Archchana Radhakrishnan

Abstract:

Introduction: Traumatic brain injury (TBI) is a leading cause of mortality among trauma patients. In the management of TBI, the main principle is avoiding cerebral ischemia, as this is a strong determiner of neurological outcomes. The use of vasoactive drugs, such as vasopressin, has an important role in maintaining cerebral perfusion pressure to prevent secondary brain injury. Current guidelines do not suggest a preferred vasoactive drug to administer in the management of TBI, and there is a paucity of information on the therapeutic potential of vasopressin following TBI. Vasopressin is also an endogenous anti-diuretic hormone (AVP), and pathways mediated by AVP play a large role in the underlying pathological processes of TBI. This creates an overlap of discussion regarding the therapeutic potential of vasopressin following TBI. Currently, its popularity lies in vasodilatory and cardiogenic shock in the intensive care setting, with increasing support for its use in haemorrhagic and septic shock. Methodology: This is a review article based on a literature review. An electronic search was conducted via PubMed, Cochrane, EMBASE, and Google Scholar. The aim was to identify clinical studies looking at the therapeutic administration of vasopressin in severe traumatic brain injury. The primary aim was to look at the neurological outcome of patients. The secondary aim was to look at surrogate markers of cerebral perfusion measurements, such as cerebral perfusion pressure, cerebral oxygenation, and cerebral blood flow. Results: Eight papers were included in the final number. Three were animal studies; five were human studies, comprised of three case reports, one retrospective review of data, and one randomised control trial. All animal studies demonstrated the benefits of vasopressors in TBI management. One animal study showed the superiority of vasopressin in reducing intracranial pressure and increasing cerebral oxygenation over a catecholaminergic vasopressor, phenylephrine. All three human case reports were supportive of vasopressin as a rescue therapy in catecholaminergic-resistant hypotension. The retrospective review found vasopressin did not increase cerebral oedema in TBI patients compared to catecholaminergic vasopressors; and demonstrated a significant reduction in the requirements of hyperosmolar therapy in patients that received vasopressin. The randomised control trial results showed no significant differences in primary and secondary outcomes between TBI patients receiving vasopressin versus those receiving catecholaminergic vasopressors. Apart from the randomised control trial, the studies included are of low-level evidence. Conclusion: Studies favour vasopressin within certain parameters of cerebral function compared to control groups. However, the neurological outcomes of patient groups are not known, and animal study results are difficult to extrapolate to humans. It cannot be said with certainty whether vasopressin’s benefits stand above usage of other vasoactive drugs due to the weaknesses of the evidence. Further randomised control trials, which are larger, standardised, and rigorous, are required to improve knowledge in this field.

Keywords: catecholamines, cerebral perfusion pressure, traumatic brain injury, vasopressin, vasopressors

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5089 Comparative Performance Analysis for Selected Behavioral Learning Systems versus Ant Colony System Performance: Neural Network Approach

Authors: Hassan M. H. Mustafa

Abstract:

This piece of research addresses an interesting comparative analytical study. Which considers two concepts of diverse algorithmic computational intelligence approaches related tightly with Neural and Non-Neural Systems. The first algorithmic intelligent approach concerned with observed obtained practical results after three neural animal systems’ activities. Namely, they are Pavlov’s, and Thorndike’s experimental work. Besides a mouse’s trial during its movement inside figure of eight (8) maze, to reach an optimal solution for reconstruction problem. Conversely, second algorithmic intelligent approach originated from observed activities’ results for Non-Neural Ant Colony System (ACS). These results obtained after reaching an optimal solution while solving Traveling Sales-man Problem (TSP). Interestingly, the effect of increasing number of agents (either neurons or ants) on learning performance shown to be similar for both introduced systems. Finally, performance of both intelligent learning paradigms shown to be in agreement with learning convergence process searching for least mean square error LMS algorithm. While its application for training some Artificial Neural Network (ANN) models. Accordingly, adopted ANN modeling is a relevant and realistic tool to investigate observations and analyze performance for both selected computational intelligence (biological behavioral learning) systems.

Keywords: artificial neural network modeling, animal learning, ant colony system, traveling salesman problem, computational biology

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