Search results for: seeding effect
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14809

Search results for: seeding effect

8719 Pharmacological Mechanisms of an Indolic Compound in Chemoprevention of Colonic Acf Formation in Azoxymethane-Induced Colon Cancer Rat Model and Cell Lines

Authors: Nima Samie, Sekaran Muniandy, Zahurin Mohamed, M. S. Kanthimathi

Abstract:

Although number of indole containing compounds have been reported to have anticancer properties in vitro but only a few of them show potential as anticancer compounds in vivo. The current study was to evaluate the mechanism of cytotoxicity of selected indolic compound in vivo and in vitro. In this context, we determined the potency of the compound in the induction of apoptosis, cell cycle arrest, and cytoskeleton rearrangement. HT-29, WiDr, CCD-18Co, human monocyte/macrophage CRL-9855, and B lymphocyte CCL-156 cell lines were used to determine the IC50 of the compound using the MTT assay. Analysis of apoptosis was carried out using immunofluorescence, acridine orange/ propidium iodide double staining, Annexin-V-FITC assay, evaluation of the translocation of NF-kB, oxygen radical antioxidant capacity, quenching of reactive oxygen species content, measurement of LDH release, caspase-3/-7, -8 and -9 assays and western blotting. The cell cycle arrest was examined using flowcytometry and gene expression was assessed using qPCR array. Results displayed a potent suppressive effect on HT-29 and WiDr after 24 h of treatment with IC50 value of 2.52±0.34 µg/ml and 2.13±0.65 µg/ml respectively. This cytotoxic effect on normal, monocyte/macrophage and B-cells was insignificant. Dipping in the mitochondrial membrane potential and increased release of cytochrome c from the mitochondria indicated induction of the intrinsic apoptosis pathway by the compound. Activation of this pathway was further evidenced by significant activation of caspase-9 and 3/7. The compound was also shown to activate the extrinsic pathways of apoptosis via activation of caspase-8 which is linked to the suppression of NF-kB translocation to the nucleus. Cell cycle arrest in the G1 phase and up-regulation of glutathione reductase, based on excessive ROS production were also observed. These findings were further investigated for inhibitory efficiency of the compound on colonic aberrant crypt foci in male rats. Rats were divided in to 5 groups: vehicle, cancer control, positive control groups and the groups treated with 25 and 50 mg/kg of compounds for 10 weeks. Administration of compound suppressed total colonic ACF formation up to 73.4%. The results also showed that treatment with the compound significantly reduced the level of malondialdehyde while increasing superoxide dismutase and catalase activities. Furthermore, the down-regulation of PCNA and Bcl2 and the up-regulation of Bax was confirmed by immunohistochemical staining. The outcome of this study suggest sthat the indolic compound is a potent anti-cancer agent against colon cancer and can be further evaluated by animal trial.

Keywords: indolic compound, chemoprevention, crypt, azoxymethane, colon cancer

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8718 Effect of Particle Size Variations on the Tribological Properties of Porcelain Waste Added Epoxy Composites

Authors: B. Yaman, G. Acikbas, N. Calis Acikbas

Abstract:

Epoxy based materials have advantages in tribological applications due to their unique properties such as light weight, self-lubrication capacity and wear resistance. On the other hand, their usage is often limited by their low load bearing capacity and low thermal conductivity values. In this study, it is aimed to improve tribological and also mechanical properties of epoxy by reinforcing with ceramic based porcelain waste. It is well-known that the reuse or recycling of waste materials leads to reduction in production costs, ease of manufacturing, saving energy, etc. From this perspective, epoxy and epoxy matrix composites containing 60wt% porcelain waste with different particle size in the range of below 90µm and 150-250µm were fabricated, and the effect of filler particle size on the mechanical and tribological properties was investigated. The microstructural characterization was carried out by scanning electron microscopy (SEM), and phase analysis was determined by X-ray diffraction (XRD). The Archimedes principle was used to measure the density and porosity of the samples. The hardness values were measured using Shore-D hardness, and bending tests were performed. Microstructural investigations indicated that porcelain particles were homogeneously distributed and no agglomerations were encountered in the epoxy resin. Mechanical test results showed that the hardness and bending strength were increased with increasing particle size related to low porosity content and well embedding to the matrix. Tribological behavior of these composites was evaluated in terms of friction, wear rates and wear mechanisms by ball-on-disk contact with dry and rotational sliding at room temperature against WC ball with a diameter of 3mm. Wear tests were carried out at room temperature (23–25°C) with a humidity of 40 ± 5% under dry-sliding conditions. The contact radius of cycles was set to 5 mm at linear speed of 30 cm/s for the geometry used in this study. In all the experiments, 3N of constant test load was applied at a frequency of 8 Hz and prolonged to 400m wear distance. The friction coefficient of samples was recorded online by the variation in the tangential force. The steady-state CoFs were changed in between 0,29-0,32. The dimensions of the wear tracks (depth and width) were measured as two-dimensional profiles by a stylus profilometer. The wear volumes were calculated by integrating these 2D surface areas over the diameter. Specific wear rates were computed by dividing the wear volume by the applied load and sliding distance. According to the experimental results, the use of porcelain waste in the fabrication of epoxy resin composites can be suggested to be potential materials due to allowing improved mechanical and tribological properties and also providing reduction in production cost.

Keywords: epoxy composites, mechanical properties, porcelain waste, tribological properties

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8717 Piracy Killed the Radio Star: A System Archetype Analysis of Digital Music Theft

Authors: Marton Gergely

Abstract:

Digital experience goods, such as music and video, are readily available and easily accessible through a sundry of illegal mediums. Furthermore, the rate of music theft has been increasing at a seemingly unstoppable rate. Instead of studying the effect of copyright infringement on affected shareholders, this paper aims to examine the overall impact that digital music piracy has on society as a whole. Through a systems dynamics approach, an archetype is built to model the behavior of both legal and illegal music users. Additionally, the effects over time are considered. The conceptual model suggests that if piracy continues to grow at the current pace, industry shareholders will eventually lose the motivation to supply new music. In turn, this tragedy would affect not only the illegal players, but legal consumers as well, by means of a decrease in overall quality of life.

Keywords: music piracy, illegal downloading, tragedy of the commons, system archetypes

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8716 Adsorption of Toluene from Aqueous Solutions by Porous Clay Hetero-Structures

Authors: F. Asadi, M. M. Zerafat, S. Sabbaghi

Abstract:

Among water pollutants, volatile organic compounds can cause severe long lasting effects not only on biotic organism but also on human health. As a result, this material group has attracted more attention in recent years. Adsorption is one of the common processes for remediation of aromatic compounds. In this study, porous clay hetrostructers (PCHs) are synthesized through gallery template approach and cetyltrimethylammonium bromide and dodecylamine used as template and co-template, respectively. Porous clay is characterized by XRD and FTIR. Batch adsorption experiments were carried out to investigate the effect of various adsorption parameters like adsorbent dosage, pH, initial concentration and contact time. It was found that by increasing adsorbent dosage from 0.5gr/lit to 4gr/lit, toluene removal is increased from 34% to 88.1%. Increasing contact time and decreasing the pH of aqueous solution increases toluene removal efficiency.

Keywords: adsorption, clay, nano-porous, toluene

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8715 Low Cost Inertial Sensors Modeling Using Allan Variance

Authors: A. A. Hussen, I. N. Jleta

Abstract:

Micro-electromechanical system (MEMS) accelerometers and gyroscopes are suitable for the inertial navigation system (INS) of many applications due to the low price, small dimensions and light weight. The main disadvantage in a comparison with classic sensors is a worse long term stability. The estimation accuracy is mostly affected by the time-dependent growth of inertial sensor errors, especially the stochastic errors. In order to eliminate negative effect of these random errors, they must be accurately modeled. Where the key is the successful implementation that depends on how well the noise statistics of the inertial sensors is selected. In this paper, the Allan variance technique will be used in modeling the stochastic errors of the inertial sensors. By performing a simple operation on the entire length of data, a characteristic curve is obtained whose inspection provides a systematic characterization of various random errors contained in the inertial-sensor output data.

Keywords: Allan variance, accelerometer, gyroscope, stochastic errors

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8714 The Intention to Use E-Money Transaction: The Moderating Effect of Security in Conceptual Frammework

Authors: Husnil Khatimah, Fairol Halim

Abstract:

This research examines the moderating impact of security on intention to use e-money that adapted from some variables of the TAM (Technology Acceptance Model) and TPB (Theory of Planned Behavior). This study will use security as moderating variable and finds these relationship depends on customer intention to use e-money as payment tools. The conceptual framework of e-money transactions was reviewed to understand behavioral intention of consumers from perceived usefulness, perceived ease of use, perceived behavioral control and security. Quantitative method will be utilized as sources of data collection. A total of one thousand respondents will be selected using quota sampling method in Medan, Indonesia. Descriptive analysis and Multiple Regression analysis will be conducted to analyze the data. The article ended with suggestion for future studies.

Keywords: e-money transaction, TAM & TPB, moderating variable, behavioral intention, conceptual paper

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8713 Biodiesel Production from Palm Oil Using an Oscillatory Baffled Reactor

Authors: Malee Santikunaporn, Tattep Techopittayakul, Channarong Asavatesanupap

Abstract:

Biofuel production especially that of biodiesel has gained tremendous attention during the last decade due to environmental concerns and shortage in petroleum oil reservoir. This research aims to investigate the influences of operating parameters, such as the alcohol-to-oil molar ratio (4:1, 6:1, and 9:1) and the amount of catalyst (1, 1.5, and 2 wt.%) on the trans esterification of refined palm oil (RPO) in a medium-scale oscillatory baffle reactor.  It has been shown that an increase in the methanol-to-oil ratio resulted in an increase in fatty acid methyl esters (FAMEs) content. The amount of catalyst has an insignificant effect on the FAMEs content. Engine testing was performed on B0 (100 v/v% diesel) and blended fuel or B50 (50 v/v% diesel). Combustion of B50 was found to give lower torque compared to pure diesel. Exhaust gas from B50 was found to contain lower concentration of CO and CO2.

Keywords: biodiesel, palm oil, transesterification, oscillatory baffled reactor

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8712 Development of Model for Effective Sub- District Municipality Wastewater Management

Authors: Vitool Suksankavanich

Abstract:

This preliminary research aimed to explore the development of wastewater management of Bang Pu Sub- District Municipality, Samutprakan Province, in order to establish appropriate model for effective wastewater management that fit to the context of the area. The research posed three questions: [i] to what extent the promotion of social responsibility awareness built among the local community resulted in effectiveness of the local wastewater management; [ii] did the waste disposal management of Bang Pu Industrial Estate contribute to the overall environmental quality of Bang Pu Sub- District Municipality; and [iii] did the relationship between the community and the industrial factories have any effect on the wastewater management. The in- depth interview revealed main obstacles occurred in the process of wastewater management in the area. The fieldwork also contributed to a product of an appropriate model of effective wastewater management.

Keywords: legitimacy theory, stakeholder theory, social responsibility, wastewater management

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8711 Impact of Normative Institutional Factors on Sustainability Reporting

Authors: Lina Dagilienė

Abstract:

The article explores the impact of normative institutional factors on the development of sustainability reporting. The vast majority of research in the scientific literature focuses on mandatory institutional factors, i.e. how public institutions and market regulators affect sustainability reporting. Meanwhile, there is lack of empirical data for the impact of normative institutional factors. The effect of normative factors in this paper is based on the role of non-governmental organizations (NGO) and institutional theory. The case of Global Compact Local Network in the developing country was examined. The research results revealed that in the absence of regulated factors, companies were not active with regard to social disclosures; they presented non-systemized social information of a descriptive nature. Only 10% of sustainability reports were prepared using the GRI methodology. None of the reports were assured by third parties.

Keywords: institutional theory, normative, sustainability reporting, Global Compact Local Network

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8710 Productive Efficiency in Asean Banking

Authors: Suhartono Suhartono

Abstract:

Issue of cost efficiency is then becoming pivotal point because public expect cost of banking operation reducing and benefited of consumers. This study examines the determinants of cost efficiency of banks operating in 8 member countries of the Association of Southeast Asian Nations (ASEAN). This study uses economics theory approach to examine the existence of economies of scale in the ASEAN Banking market especially on its impact on cost efficiency. We apply concept of average cost (AC) as a proxy for the cost efficiency. We find that economies of scale is existing in the banking market indicating scale and scope economies should be considered in the industrial policy. The stronger capital position is also positive to efficiency means stronger capitalized banks are more efficient. Bank that remunerates better tend to be more efficient as result economic capital effect.

Keywords: cost efficiency, ASEAN, economies of scale, issue of cost

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8709 Excitonic Refractive Index Change in High Purity GaAs Modulator at Room Temperature for Optical Fiber Communication Network

Authors: Durga Prasad Sapkota, Madhu Sudan Kayastha, Koichi Wakita

Abstract:

In this paper, we have compared and analyzed the electron absorption properties between with and without excitonic effect bulk in high purity GaAs spatial light modulator for an optical fiber communication network. The electroabsorption properties such as absorption spectra, change in absorption spectra, change in refractive index and extinction ratio have been calculated. We have also compared the result of absorption spectra and change in absorption spectra with the experimental results and found close agreement with experimental results.

Keywords: exciton, refractive index change, extinction ratio, GaAs

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8708 Improvement in Ni (II) Adsorption Capacity by Using Fe-Nano Zeolite

Authors: Pham-Thi Huong, Byeong-Kyu Lee, Jitae Kim, Chi-Hyeon Lee

Abstract:

Fe-nano zeolite adsorbent was used for removal of Ni (II) ions from aqueous solution. The adsorbent was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and the surface area Brunauer–Emmett–Teller (BET) using for analysis of functional groups, morphology and surface area. Bath adsorption experiments were analyzed on the effect of pH, time, adsorbent doses and initial Ni (II) concentration. The optimum pH for Ni (II) removal using Fe-nano zeolite was found at 5.0 and 90 min of reaction time. The maximum adsorption capacity of Ni (II) was 231.68 mg/g based on the Langmuir isotherm. The kinetics data for the adsorption process was fitted with the pseudo-second-order model. The desorption of Ni (II) from Ni-loaded Fe-nano zeolite was analyzed and even after 10 cycles 72 % desorption was achieved. These finding supported that Fe-nano zeolite with high adsorption capacity, high reuse ability would be utilized for Ni (II) removal from water.

Keywords: Fe-nano zeolite, adsorption, Ni (II) removal, regeneration

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8707 Creating a Virtual Perception for Upper Limb Rehabilitation

Authors: Nina Robson, Kenneth John Faller II, Vishalkumar Ahir, Arthur Ricardo Deps Miguel Ferreira, John Buchanan, Amarnath Banerjee

Abstract:

This paper describes the development of a virtual-reality system ARWED, which will be used in physical rehabilitation of patients with reduced upper extremity mobility to increase limb Active Range of Motion (AROM). The ARWED system performs a symmetric reflection and real-time mapping of the patient’s healthy limb on to their most affected limb, tapping into the mirror neuron system and facilitating the initial learning phase. Using the ARWED, future experiments will test the extension of the action-observation priming effect linked to the mirror-neuron system on healthy subjects and then stroke patients.

Keywords: physical rehabilitation, mirror neuron, virtual reality, stroke therapy

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8706 Analysis of Reflection of Elastic Waves in Three Dimensional Model Comprised with Viscoelastic Anisotropic Medium

Authors: Amares Chattopadhyay, Akanksha Srivastava

Abstract:

A unified approach to study the reflection of a plane wave in three-dimensional model comprised of the triclinic viscoelastic medium. The phase velocities of reflected qP, qSV and qSH wave have been calculated for the concerned medium by using the eigenvalue approach. The generalized method has been implemented to compute the complex form of amplitude ratios. Further, we discussed the nature of reflection coefficients of qP, qSV and qSH wave. The viscoelastic parameter, polar angle and azimuthal angle are found to be strongly influenced by amplitude ratios. The research article is particularly focused to study the effect of viscoelasticity associated with highly anisotropic media which exhibits the notable information about the reflection coefficients of qP, qSV, and qSH wave. The outcomes may further useful to the better exploration of all types of hydrocarbon reservoir and advancement in the field of reflection seismology.

Keywords: amplitude ratios, three dimensional, triclinic, viscoelastic

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8705 Enhancement and Characterization of Titanium Surfaces with Sandblasting and Acid Etching for Dental Implants

Authors: Busra Balli, Tuncay Dikici, Mustafa Toparli

Abstract:

Titanium and its alloys have been used extensively over the past 25 years as biomedical materials in orthopedic and dental applications because of their good mechanical properties, corrosion resistance, and biocompatibility. It is known that the surface properties of titanium implants can enhance the cellular response and play an important role in Osseo integration. The rate and quality of Osseo integration in titanium implants are related to their surface properties. The purpose of this investigation was to evaluate the effect of sandblasting and acid etching on surface morphology, roughness, the wettability of titanium. The surface properties will be characterized by scanning electron microscopy and contact angle and roughness measurements. The results show that surface morphology, roughness, and wettability were changed and enhanced by these treatments.

Keywords: dental implant, etching, surface modifications, surface morphology, surface roughness

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8704 Effect of Using Crumb Rubber with Warm-Mix-Asphalt Additive in Laboratory and Field Aging

Authors: Mustafa Akpolat, Baha Vural Kök

Abstract:

Using a waste material such as crumb rubber (CR) obtained by waste tires has become an important issue in respect to sustainability. However, the CR modified mixture also requires high manufacture temperature as a polymer modified mixture. For this reason in this study, it is intended to produce a CR modified mixture with warm mix asphalt additives in the same mixture. Asphalt mixtures produced by pure, 10%CR, 10%CR+3% Sasobit and 10%CR+0.7% Evotherm were subjected to aging procedure in the laboratory and the field. The indirect tensile repeated tests were applied to aged and original specimens. It was concluded that the fatigue life of the mixtures increased significantly with the increase of aging time. CR+Sasobit modified mixture aged at the both field and laboratory gave the highest load cycle among the mixtures.

Keywords: crumb rubber, warm mix asphalt, aging, fatigue

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8703 Determination of 1-Deoxynojirimycin and Phytochemical Profile from Mulberry Leaves Cultivated in Indonesia

Authors: Yasinta Ratna Esti Wulandari, Vivitri Dewi Prasasty, Adrianus Rio, Cindy Geniola

Abstract:

Mulberry is a plant that widely cultivated around the world, mostly for silk industry. In recent years, the study showed that the mulberry leaves have an anti-diabetic effect which mostly comes from the compound known as 1-deoxynojirimycin (DNJ). DNJ is a very potent α-glucosidase inhibitor. It will decrease the degradation rate of carbohydrates in digestive tract, leading to slower glucose absorption and reducing the post-prandial glucose level significantly. The mulberry leaves also known as the best source of DNJ. Since then, the DNJ in mulberry leaves had received a considerable attention, because of the increased number of diabetic patients and the raise of people awareness to find a more natural cure for diabetic. The DNJ content in mulberry leaves varied depend on the mulberry species, leaf’s age, and the plant’s growth environment. Few of the mulberry varieties that were cultivated in Indonesiaare Morus alba var. kanva-2, M. alba var. multicaulis, M. bombycis var. lembang, and M. cathayana. The lack of data concerning phytochemicals contained in the Indonesian mulberry leaves are restraining their use in the medicinal field. The aim of this study is to fully utilize the use of mulberry leaves cultivated in Indonesia as a medicinal herb in local, national, or global community, by determining the DNJ and other phytochemical contents in them. This study used eight leaf samples which are the young leaves and mature leaves of both Morus alba var. kanva-2, M. alba var. multicaulis, M. bombycis var. lembang, and M. cathayana. The DNJ content was analyzed using reverse phase high performance liquid chromatography (HPLC). The stationary phase was silica C18 column and the mobile phase was acetonitrile:acetic acid 0.1% 1:1 with elution rate 1 mL/min. Prior to HPLC analysis the samples were derivatized with FMOC to ensure the DNJ detectable by VWD detector at 254 nm. Results showed that the DNJ content in samples are ranging from 2.90-0.07 mg DNJ/ g leaves, with the highest content found in M. cathayana mature leaves (2.90 ± 0.57 mg DNJ/g leaves). All of the mature leaf samples also found to contain higher amount of DNJ from their respective young leaf samples. The phytochemicals in leaf samples was tested using qualitative test. Result showed that all of the eight leaf samples contain alkaloids, phenolics, flavonoids, tannins, and terpenes. The presence of this phytochemicals contribute to the therapeutic effect of mulberry leaves. The pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) analysis was also performed to the eight samples to quantitatively determine their phytochemicals content. The pyrolysis temperature was set at 400 °C, with capillary column Phase Rtx-5MS 60 × 0.25 mm ID stationary phase and helium gas mobile phase. Few of the terpenes found are known to have anticancer and antimicrobial properties. From all the results, all of four samples of mulberry leaves which are cultivated in Indonesia contain DNJ and various phytochemicals like alkaloids, phenolics, flavonoids, tannins, and terpenes which are beneficial to our health.

Keywords: Morus, 1-deoxynojirimycin, HPLC, Py-GC-MS

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8702 Mercury and Selenium Levels in Swordfish (Xiphias gladius) Fished in the Exclusive Economic Zone of the Republic of Seychelles

Authors: Stephanie Hollanda, Nathalie Bodin, Carine Churlaud, Paco Bustamante

Abstract:

Total mercury (Hg), selenium (Se) and Hg-Se ratios were analyzed in the white muscle, liver and gonads of swordfish, in order to compare concentration between the different tissues and sex, and also the effect of size (fork length). The results show significant difference between tissue types, with the liver having the highest concentration of both Hg and Se. Positive significant correlations between moles of Hg and Se were obtained in the liver and white muscle, but no relationship was obtained in the gonads. No difference in the concentration of Hg and Se was obtained between the sexes in the tissue types, except for Hg in the gonads, which were found to be higher in males. Significant negative relationships were obtained when the Hg-Se ratio was plotted against fork length in all three tissue types.

Keywords: bioaccumulation, large pelagic fish, mercury, selenium, western Indian Ocean

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8701 Industrial Process Mining Based on Data Pattern Modeling and Nonlinear Analysis

Authors: Hyun-Woo Cho

Abstract:

Unexpected events may occur with serious impacts on industrial process. This work utilizes a data representation technique to model and to analyze process data pattern for the purpose of diagnosis. In this work, the use of triangular representation of process data is evaluated using simulation process. Furthermore, the effect of using different pre-treatment techniques based on such as linear or nonlinear reduced spaces was compared. This work extracted the fault pattern in the reduced space, not in the original data space. The results have shown that the non-linear technique based diagnosis method produced more reliable results and outperforms linear method.

Keywords: process monitoring, data analysis, pattern modeling, fault, nonlinear techniques

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8700 Towards the Inhibition Mechanism of Lysozyme Fibrillation by Hydrogen Sulfide

Authors: Indra Gonzalez Ojeda, Tatiana Quinones, Manuel Rosario, Igor Lednev, Juan Lopez Garriga

Abstract:

Amyloid fibrils are stable aggregates of misfolded protein associated with many neurodegenerative disorders. It has been shown that hydrogen sulfide (H2S), inhibits the fibrillation of lysozyme through the formation of trisulfide (S-S-S) bonds. However, the overall mechanism remains elusive. Here, the concentration dependence of H2S effect was investigated using Atomic force microscopy (AFM), non-resonance Raman spectroscopy, Deep-UV Raman spectroscopy and circular dichroism (CD). It was found that small spherical aggregates with trisulfide bonds and a unique secondary structure were formed instead of amyloid fibrils when adding concentrations of 25 mM and 50 mM of H2S. This could indicate that H2S might serve as a protecting agent for the protein. However, further characterization of these aggregates and their trisulfide bonds is needed to fully unravel the function H2S has on protein fibrillation.

Keywords: amyloid fibrils, hydrogen sulfide, protein folding, raman spectroscopy

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8699 Investigating the Urban Heat Island Phenomenon in A Desert City Aiming at Sustainable Buildings

Authors: Afifa Mohammed, Gloria Pignatta, Mattheos Santamouris, Evangelia Topriska

Abstract:

Climate change is one of the global challenges that is exacerbated by the rapid growth of urbanizations. Urban Heat Island (UHI) phenomenon can be considered as an effect of the urbanization and it is responsible together with the Climate change of the overheating of urban cities and downtowns. The purpose of this paper is to quantify and perform analysis of UHI Intensity in Dubai, United Arab Emirates (UAE), through checking the relationship between the UHI and different meteorological parameters (e.g., temperature, winds speed, winds direction). Climate data were collected from three meteorological stations in Dubai (e.g., Dubai Airport - Station 1, Al-Maktoum Airport - Station 2 and Saih Al-Salem - Station 3) for a period of five years (e.g., 2014 – 2018) based upon hourly rates, and following clustering technique as one of the methodology tools of measurements. The collected data of each station were divided into six clusters upon the winds directions, either from the seaside or from the desert side, or from the coastal side which is in between both aforementioned winds sources, to investigate the relationship between temperature degrees and winds speed values through UHI measurements for Dubai Airport - Station 1 compared with the same of Al-Maktoum Airport - Station 2. In this case, the UHI value is determined by the temperature difference of both stations, where Station 1 is considered as located in an urban area and Station 2 is considered as located in a suburban area. The same UHI calculations has been applied for Al-Maktoum Airport - Station 2 and Saih Salem - Station 3 where Station 2 is considered as located in an urban area and Station 3 is considered as located in a suburban area. The performed analysis aims to investigate the relation between the two environmental parameters (e.g., Temperature and Winds Speed) and the Urban Heat Island (UHI) intensity when the wind comes from the seaside, from the desert, and the remaining directions. The analysis shows that the correlation between the temperatures with both UHI intensity (e.g., temperature difference between Dubai Airport - Station 1 and Saih Al-Salem - Station 3 and between Al-Maktoum Airport - Station 2 and Saih Al-Salem - Station 3 (through station 1 & 2) is strong and has a negative relationship when the wind is coming from the seaside comparing between the two stations 1 and 2, while the relationship is almost zero (no relation) when the wind is coming from the desert side. The relation is independent between the two parameters, e.g., temperature and UHI, on Station 2, during the same procedures, the correlation between the urban heat island UHI phenomenon and wind speed is weak for both stations when wind direction is coming from the seaside comparing the station 1 and 2, while it was found that there’s no relationship between urban heat island phenomenon and wind speed when wind direction is coming from desert side. The conclusion could be summarized saying that the wind coming from the seaside or from the desert side have a different effect on UHI, which is strongly affected by meteorological parameters. The output of this study will enable more determination of UHI phenomenon under desert climate, which will help to inform about the UHI phenomenon and intensity and extract recommendations in two main categories such as planning of new cities and designing of buildings.

Keywords: meteorological data, subtropical desert climate, urban climate, urban heat island (UHI)

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8698 Effect of Storage Time on the Properties of Seeds, Oil and Biodiesel from Reutealis trisperma

Authors: Muhammad Yusuf Abduh, Syaripudin, Laksmitha Dyanie, Robert Manurung

Abstract:

The time profile of moisture content for different fractions (PT-3, PT-7, PT-14, NPT-21) of trisperma seeds (Reutealis trisperma) was determined at a relative humidity of 67% and 27°C for a four months period. The diffusion coefficient of water in the trisperma seeds was determined using an analytical solution of instationary diffusion equation and used to model the moisture content in the seeds. The total oil content of the seeds and the acid value of the extracted oil from the stored seeds were periodically measured for four months. The acid value of the extracted oil from the stored seeds increased for all conditions (1.1 to 2.8 mg KOH/g for PT-3, 1.9 to 9.9 mg KOH/g for PT-7, 3.4 to 11.6 mg KOH/g for PT-14 and 4.7 to 25.4 mg KOH/g for NPT-21). The acid value of trisperma oil and biodiesel that has been stored for four months (27°C, closed container) was also determined. Upon storage, the acid value of trisperma oil and biodiesel only slightly increased from 1.1 to 1.3 mg KOH/g and 0.4 to 0.43 mg KOH/g, respectively.

Keywords: acid value, biodiesel, moisture content, Reutealis trisperma, storage

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8697 Haematological Indices of West African Dwarf Goats Fed Diets Containing Varying Levels of Sodium Humate

Authors: Ubu Isaiah, Gambo D.

Abstract:

Haematological studies are an important diagnosis of nutritional studies. The study investigated the haematological parameters of West African Dwarf (WAD) goats fed a diet containing different levels of sodium humate. Twenty (20) WAD bucks weighing between 8.154 ± 0.340 kg were used for this study. The bucks were randomly allotted to four dietary treatments containing 0, 5, 10, and 15 g/kg diet of sodium humate laid out as a completely randomized design. Data on haematological parameters were obtained and statistically analysed using the generalized linear model (GLM) of the Statistical Package for Social Sciences (SPSS) (version 23). Results showed that sodium humate supplementation (p <0.05) has no significant effect on Neutrophils, Eosinophil, Basophils, and Monocytes, respectively. It was recommended up to 15 g/kg diet supplementation of sodium humate sufficiently enhance the performance of WAD goats as well the improving their haematological indices.

Keywords: haematological indices, goat, sodium humate

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8696 The Effect of Improvement Programs in the Mean Time to Repair and in the Mean Time between Failures on Overall Lead Time: A Simulation Using the System Dynamics-Factory Physics Model

Authors: Marcel Heimar Ribeiro Utiyama, Fernanda Caveiro Correia, Dario Henrique Alliprandini

Abstract:

The importance of the correct allocation of improvement programs is of growing interest in recent years. Due to their limited resources, companies must ensure that their financial resources are directed to the correct workstations in order to be the most effective and survive facing the strong competition. However, to our best knowledge, the literature about allocation of improvement programs does not analyze in depth this problem when the flow shop process has two capacity constrained resources. This is a research gap which is deeply studied in this work. The purpose of this work is to identify the best strategy to allocate improvement programs in a flow shop with two capacity constrained resources. Data were collected from a flow shop process with seven workstations in an industrial control and automation company, which process 13.690 units on average per month. The data were used to conduct a simulation with the System Dynamics-Factory Physics model. The main variables considered, due to their importance on lead time reduction, were the mean time between failures and the mean time to repair. The lead time reduction was the output measure of the simulations. Ten different strategies were created: (i) focused time to repair improvement, (ii) focused time between failures improvement, (iii) distributed time to repair improvement, (iv) distributed time between failures improvement, (v) focused time to repair and time between failures improvement, (vi) distributed time to repair and between failures improvement, (vii) hybrid time to repair improvement, (viii) hybrid time between failures improvements, (ix) time to repair improvement strategy towards the two capacity constrained resources, (x) time between failures improvement strategy towards the two capacity constrained resources. The ten strategies tested are variations of the three main strategies for improvement programs named focused, distributed and hybrid. Several comparisons among the effect of the ten strategies in lead time reduction were performed. The results indicated that for the flow shop analyzed, the focused strategies delivered the best results. When it is not possible to perform a large investment on the capacity constrained resources, companies should use hybrid approaches. An important contribution to the academy is the hybrid approach, which proposes a new way to direct the efforts of improvements. In addition, the study in a flow shop with two strong capacity constrained resources (more than 95% of utilization) is an important contribution to the literature. Another important contribution is the problem of allocation with two CCRs and the possibility of having floating capacity constrained resources. The results provided the best improvement strategies considering the different strategies of allocation of improvement programs and different positions of the capacity constrained resources. Finally, it is possible to state that both strategies, hybrid time to repair improvement and hybrid time between failures improvement, delivered best results compared to the respective distributed strategies. The main limitations of this study are mainly regarding the flow shop analyzed. Future work can further investigate different flow shop configurations like a varying number of workstations, different number of products or even different positions of the two capacity constrained resources.

Keywords: allocation of improvement programs, capacity constrained resource, hybrid strategy, lead time, mean time to repair, mean time between failures

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8695 Working Effectively with Muslim Communities in the West

Authors: Lisa Tribuzio

Abstract:

This paper explores the complexity of working with Muslim communities in Australia. It will draw upon the notions of belonging, social inclusion and effective community programming to engage Muslim communities in Western environments given the current global political climate. Factors taken into consideration for effective engagement include: family engagement, considering key practices such as Ramadan, fasting and prayer and food requirements, gender relations, core values around faith and spirituality, considering attitudes towards self disclosure in a counseling setting and the notion of Us and Them in the media and systems and its effect on minority communities. It will explore recent research in the field from Australian researchers as well as recommendations from United Nations in working with Muslim communities. It will also explore current practice models applied in Australia in engaging effectively with diverse communities and addressing racism and discrimination in innovative ways.

Keywords: Muslim, cultural diversity, social inclusion, racism

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8694 Joint Space Hybrid Force/Position Control of 6-DoF Robot Manipulator Using Neural Network

Authors: Habtemariam Alemu

Abstract:

It has been known that the performance of position and force control is highly affected by both robot dynamic and environment stiffness uncertainties. In this paper, joint space hybrid force and position control strategy with self-selecting matrix using artificial neural network compensator is proposed. The objective of the work is to improve controller robustness by applying a neural network technique in order to compensate the effect of uncertainties in the robot model. Simulation results for a 6 degree of freedom (6-DoF) manipulator and different types of environments showed the effectiveness of the suggested approach. 6-DoF Puma 560 family robot manipulator is chosen as industrial robot and its efficient dynamic model is designed using Matlab/SimMechanics library.

Keywords: robot manipulator, force/position control, artificial neural network, Matlab/Simulink

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8693 The Impact of Three Different Insecticides Against Fall Armyworms on Maize Productivity, in Somalia

Authors: Ahmed Ali Hassan

Abstract:

The fall armyworm (FAW) was first identified in 2016 in Africa. FAW is widely distributed in Somalia and severely damages the maize crop. The effect of three different pesticides used to control the autumn armyworm, Spodoptera frugiperda (Noctuidae: Lepidoptera), on maize productivity was investigated in this study. During the 2020–2021 growing season, three insecticides (Malathion 57 EC, Ampligo150 ZC, and Carbryle 85 WP) were evaluated at field demonstration plots. Our result showed that significant mortality of S. frugiperda was observed on the treatment plot treated with Amplico. After spraying, Ampligo resulted in (92.200%) larval death. Compared to Carbaryl, which was less active and only caused 36.367% mortality after application, Malathion had a moderate mortality rate of 53.733%. Consequently, our current finding shows that the three selected insecticides reduced the damage and infestation level of S. frugiperda in the maize field conditions, and the most effective treatment was Amplico.

Keywords: maize, fall armyworm, insecticides, mortality

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8692 Effect of Varied Climate, Landuse and Human Activities on the Termite (Isoptera: Insecta) Diversity in Three Different Habitats of Shivamogga District, Karnataka, India

Authors: C. M. Kalleshwaraswamy, G. S. Sathisha, A. S. Vidyashree, H. B. Pavithra

Abstract:

Isoptera are an interesting group of social insects with different castes and division of labour. They are primarily wood-feeders, but also feed on a variety of other organic substrates, such as living trees, leaf litter, soil, lichens and animal faeces. The number of species and their biomass are especially large in tropics. In natural ecosystems, they perform a beneficial role in nutrient cycles by accelerating decomposition. The magnitude and dimension of ecological role played by termites is a function of their diversity, population density, and biomass. Termite assemblage composition has a strong response to habitat disturbance and may be indicative of quantitative changes in the decomposition process. Many previous studies in Western Ghat region of India suggest increased anthropogenic activities that adversely affect the soil macrofauna and diversity. Shivamogga district provides a good opportunity to study the effect of topography, cropping pattern, human disturbance on the termite fauna, thereby acquiring accurate baseline information for conservation decision making. The district has 3 distinct agro-ecological areas such as maidan area, semi-malnad and Western Ghat region. Thus, the district provides a unique opportunity to study the effect of varied climate and anthropogenic disturbance on the termite diversity. The standard protocol of belt transects method developed by Eggleton et al. (1997) was used for sampling termites. Sampling was done at monthly interval from September-2014 to August-2015 in Western Ghats, semi-malnad and maidan habitats. The transect was 100m long and 2m wide and divided into 20 contiguous sections, each 5 x 2m in each habitat. Within each section, all the probable microhabitats of termites were searched, which include dead logs, fallen tree, branch, sticks, leaf litter, vegetation etc.,. All the castes collected were labelled, preserved in 80% alcohol, counted and identified to species level. The number of encounters of a species in the transect was used as an indicator of relative abundance of species. The species diversity, species richness, density were compared in three different habitats such as Western Ghats, semi-malnad and maidan region. The study indicated differences in the species composition in the three different habitats. A total of 15 species were recorded which belonging to four sub family and five genera in three habitats. Eleven species viz., Odontotermes obesus, O. feae, O. anamallensis, O. bellahunisensis, O. adampurensis, O. boveni, Microcerotermes fletcheri, M. pakistanicus, Nasutitermes anamalaiensis, N. indicola, N. krishna were recorded in Western Ghat region. Similarly, 11 species viz., Odontotermes obesus, O. feae, O. anamallensis, O. bellahunisensis, O. hornii, O. bhagwathi, Microtermes obesi, Microcerotermes fletcheri, M. pakistanicus, Nasutitermes indicola and Pericapritermes sp. were recorded in semi-malnad habitat. However, only four species viz., O. obesus, O. feae, Microtemes obesi and Pericapritermes sp. species were recorded in maidan area. Shannon’s wiener diversity index (H) showed that Western Ghats had more species dominance (1.56) followed by semi- malnad (1.36) and lowest in maidan (0.89) habitats. Highest value of simpson’s index (D) was observed in Western Ghats habitat (0.70) with more diverse species followed by semi-malnad (0.58) and lowest in maidan (0.53). Similarly, evenness was highest (0.65) in Western Ghats followed by maidan (0.64) and least in semi-malnad habitat (0.54). Menhinick’s index (Dmn) value was ranging from 0.03 to 0.06 in different habitats in the study area. Highest index was observed in Western Ghats (0.06) followed by semi-malnad (0.05) and lowest in maidan (0.03). The study conclusively demonstrated that Western Ghat had highest species diversity compared to semi-malnad and maidan habitat indicating these two habitats are continuously subjected to anthropogenic disturbances. Efforts are needed to conserve the uncommon species which otherwise may become extinct due to human activities.

Keywords: anthropogenic disturbance, isoptera, termite species diversity, Western ghats

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8691 Chelator-assisted Phytoextraction of Nickel from Nickeliferous Lateritic Soil by Phyllanthus sp. nov.

Authors: Grecco M. Ante, Princess Rochelle O. Gan

Abstract:

Plants that can absorb greater than 10,000 µg Ni/g dry mass in their stems and leaves are termed as ‘hypernickelophores’. Chelators are chemicals that make the metals in the soil more soluble, making them a potential enhancer for phytoextraction. This study aims to observe the effect of different concentrations of the chelating agent ethylene diamine tetraacetate (EDTA) on the metal uptake (or rate of phytoextraction) of Nickel by Phyllanthus sp. nov. The plant is found to be a hyperickelophore in normal conditions. The addition of EDTA increased the metal uptake of the plant. The increasing amount of the chelating agent causes a decrease in the phytoextraction of the plant but moves the onset of its peak of maximum nickel content in its tissue to an earlier time. The chelator-assisted phytoextraction of nickel by Phyllanthus sp. nov. is proven to be an efficient auxiliary mining operation for nickel laterite mines.

Keywords: phytomining, Phyllanthus sp. nov., EDTA, nickel, laterite

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8690 Assessment of High Frequency Solidly Mounted Resonator as Viscosity Sensor

Authors: Vinita Choudhary

Abstract:

Solidly Acoustic Resonators (SMR) based on ZnO piezoelectric material operating at a frequency of 3.96 GHz and 6.49% coupling factor are used to characterize liquids with different viscosities. This behavior of the sensor is analyzed using Finite Element Modeling. Device architectures encapsulate bulk acoustic wave resonators with MO/SiO₂ Bragg mirror reflector and the silicon substrate. The proposed SMR is based on the mass loading effect response of the sensor to the change in the resonant frequency of the resonator that is caused by the increased density due to the absorption of liquids (water, acetone, olive oil) used in theoretical calculation. The sensitivity of sensors ranges from 0.238 MHz/mPa.s to 83.33 MHz/mPa.s, supported by the Kanazawa model. Obtained results are also compared with previous works on BAW viscosity sensors.

Keywords: solidly mounted resonator, bragg mirror, kanazawa model, finite element model

Procedia PDF Downloads 82