Search results for: active%20slat

Authors: Hayani Anastasia, Junus Widjaja, Anis Nur Widayati

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In Indonesia, schistosomiasis is caused by Schistosoma japonicum with Oncomelania hupensis lindoensis as the intermediate host. Schistosomiasis can infect humans and all species of mammals. In order to achieve schistosomiasis elimination by 2020, schistosomiasis control, including environmental management, has been carried out by multi-sector. A cross-sectional study was conducted in 2018 to evaluate the multi-sectoral schistosomiasis control program. Data were collected by depth interviews of stakeholders, stool surveys, snail surveys, observation, and document reviews. About 53.6% of control programs in the schistosomiasis control roadmap were not achieved. The number of foci area found in 2018 are not significantly different compared to before the control programs. Moreover, the prevalence of schistosomiasis in the human was 0-5.1% and in mammals was the range from 0 to 10%. In order to overcome the problems, a policy about schistosomiasis as a priority program in ministries and agencies other than the Ministry of Health is needed. Innovative health promotion with interactive media also needs to be applied. Also, the schistosomiasis work team needs to be more active with the Agency of Regional Development as the leading sector.

Keywords: evaluation, Indonesia, multi-sector, schistosomiasis

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Authors: Bouzidi Abdelouahab, Ghadjati Nadhra, Bettihi Sara, Mahdeb Nadia, Daamouche Z. El Youm

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The effects of acute administration of TOTAL alkaloids, the main active principle of Datura stramonium, with toxic properties, were studied in female Albino-Wistar rats. After acute intraperitoneal administration of dose 120 mg kg-1 (≈1/3 DL50) of total alkaloids to the seeds of D. stramonium, there were no remarkable changes in general appearance and no deaths occurred in any experimental group. After 5 days a significant reduction was observed in total alkaloids of seeds. The Red Blood Cells (RBC), Hematocrit (HCT) and Hemoglobin (HGB) show significant changes in the treated groups. There were no statistical differences in Glutamic-pyruvic Transaminase (GPT), Alkaline Phosphatase (ALP), urea, glucose and total protein observed between groups. After 24 h Glutamic-Oxaloacetic Transaminase (GOT) and creatinine were significantly higher in the treated male rats than the control group histological examination of liver showed no histopathological changes.

Keywords: datura stramonium, rat, liver, kidney, alkaloids, toxicity

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Authors: Pairah Bte Satariman

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This study is carried out to evaluate Malay Language Curriculum for secondary schools in Singapore. The evaluation focuses on the implementation of Spoken Interaction Skill which was recommended by the Curriculum Review Committee in 2010. The study found that the students face difficulty in communicating interactively with others in their daily activities. The purpose of the study is to evaluate the results (products) on the implementation of this skill since 2011. The research used a qualitative method which includes oral test and interview with students and teachers teaching the subject. Preliminary findings show that generally, the students are not able to communicate interactively and fluently in the oral test unless they are given enough prompts. The teachers feel that the implementation of the skill is timely as students are more keen to use English in their daily communication even in Malay Language Classes. Teachers also mentioned the challenges in the implementation such as insufficient curriculum time and teaching materials.

Keywords: evaluation, Malay language curriculum, spoken interaction skills, communication, implementation

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Authors: Alisa Sheppental

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The focus of this paper is the impact of coronavirus-related restrictions on the legitimacy and efficacy of subaltern counter publics and political resistance. Both difficulties and alterations of strategies needed to be considered by modern political movements within the counter-public sphere will be illustrated based on recent examples of protests in Hong Kong, Thailand, Belarus, Poland, and France. The dynamics of the modern globalized world have previously required a high level of adaptability, which resulted in a number of new features of modern political resistance in contrast with previous decades, including digitalization of protests and higher involvement of previously fewer active citizens (women, elderly, people with disabilities, etc.) However, a global pandemic situation, along with massive restrictions of daily lives, provide new input for both theoretical and empirical analysis. The following paper represents an attempt to summarize coping and adapting strategies of subaltern counter publics and activist groups under coronavirus-related restrictions.

Keywords: citizenship, political activism, subaltern counterpublics, discourse ethics

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Authors: K. N. Kipreou, E. Efthmiadou, G. Kordas

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Biofouling represents one of the most crucial problems in the present maritime industries when its control still challenges the researchers all over the world. The present work is referred to the synthesis and characterization CeMo and Cu2O nanocontainers by using a wide range of techniques including scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) for marine applications. The above nanosystems will be loaded with active monomers and corrosion rendering healing ability to marine paints. The objective of this project is their ability for self-healing, self-polishing and finally for anti-corrosion activity. One of the driving forces for the exploration of CeMo, is the unique anticorrosive behavior, which will be confirmed by the electrochemistry methodology. It has be highlighted that the nanocontainers of Cu2O with the appropriate antibacterial inhibitor will improve the hydrophobicity and the morphology of the coating surfaces reducing the water friction. In summary, both novel nanoc will increase the lifetime of the paints releasing the antifouling agent in a control manner.

Keywords: marinepaints, nanocontainer, antifouling, anticorrosion, copper, electrochemistry, coating, biofouling, inhibitors, copper oxide, coating, SEM

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Authors: Sang Hun Park, Moung Young Lee, Su Min Yu, Hyun Sang Jo, Ji Hyeon Kim, Chul Gyu Song

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A near-infrared light source used as a light source in the fluorescence imaging system is suitable for use in real-time during the operation since it has no interference in surgical vision. However, fluorescence images do not have depth information. In this paper, we configured the device with the research on molecular imaging systems for monitoring thrombus imaging using fluorescence and photoacoustic. Fluorescence imaging was performed using a phantom experiment in order to search the exact location, and the Photoacoustic image was in order to detect the depth. Fluorescence image obtained when evaluated through current phantom experiments when the concentration of the contrast agent is 25μg / ml, it was confirmed that it looked sharper. The phantom experiment is has shown the possibility with the fluorescence image and photoacoustic image using an indocyanine green contrast agent. For early diagnosis of cardiovascular diseases, more active research with the fusion of different molecular imaging devices is required.

Keywords: fluorescence, photoacoustic, indocyanine green, carotid artery

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Authors: Marylene S. Eder, Dorothy M. Jao, Paolo Marc Nicolas S. Laspiñas, Pukilan A. Malim, Sarah Jean D. Raterta

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Trash Dash is an android game application developed to serve as an alternative tool to practice proper waste segregation for children ages 3 years old and above. The researchers designed the application using Unity 3D and developed the text file that served as the database of the game application. An observation of a pre-school teacher shows that children know how to throw their garbage but they do not know yet how to segregate wastes. After launching the mobile application to K-2 pupils 4 – 5 years of age, the researchers have noticed that children within this age are active and motivated to learn the difference between biodegradable and non-biodegradable. Based on the result of usability test conducted, it was concluded that the game is easy to use and children will most likely use this application frequently. Furthermore, the children may need assistance from their parents and teachers when playing the game. An actual testing of the application has been conducted to different devices as well as functionality test by Thwack Application and it can be concluded that the mobile application can be launched and installed on a device with a minimum API requirement of Gingerbread (2.3.1).

Keywords: waste segregation, android application, biodegradable, non-biodegradable

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Authors: Navonil Hazra

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The paper discusses how and why aphasia can be understood as the language of nonverbal communication in musical performance and also looks for the elements that are required to classify it as a nonverbal language. Since music is regarded as a nonverbal medium that cannot be engaged in any language, it is concerned about how aphasia might be called the language of nonverbalization. The paper also talks about how it portrays the magnificence of a performance, and how it expresses its likings or dislikes. Regarding the reasons for aphasia, the paper talks about the seizure factor and elucidates on seizure subjects as well. Furthermore, it discusses collective seizures and individual seizures. It also tries to consider aphasia as a-posteriori rather than a-priori looking at it from the lens of ‘Pure Reason’. Along with aphasia, the paper tries to make a critique of silence and the possibilities of looking at silence differently, also looking at the ontology of silence and sound. This paper also critically examines silence and the significance of gestures in performance. It also investigates whether gestures are accompanied by silence, establishing the notion of agential silence. This paper also talks about the place and role of memory in the formulation and analysis of a performance, as well as the plaguing and reclamation of memory, how memory alters the linear course of time and taunts us to look for alternative models of temporalities. This paper discusses the concept of 'auditory labour', with active and passive listening.

Keywords: aphasia, gestures, memory, silence

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Authors: Pankaj Negi

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Nowadays the demand for receiving the high quality electrical energy is being increasing as consumer wants not only reliable but also quality power. Custom power instruments are of the most well-known compensators of power quality in distributed network. This paper present a comprehensive review of compensating custom power devices mainly DSTATCOM (distribution static compensator),DVR (dynamic voltage restorer), and UPQC (unified power quality compensator) and also deals with sliding mode control and its applications to custom power devices. The sliding mode control strategy provides robustness to custom power device and enhances the dynamic response for compensating voltage sag, swell, voltage flicker, and voltage harmonics. The aim of this paper is to provide a broad perspective on the status of compensating devices in electric power distribution system and sliding mode control strategies to researchers and application engineers who are dealing with power quality and stability issues.

Keywords: active power filters(APF), custom power device(CPD), DSTATCOM, DVR, UPQC, sliding mode control (SMC), power quality

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Authors: B. Benalioua, I. Benyamina, A. Bentouami, B. Boury

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The objective of this study is based on the synthesis of a new photocatalyst based on TiO2 and its application in the photo-degradation of an acid dye under the visible light. The material obtained was characterized by different techniques like diffuse reflectance UV–Vis spectroscopy (DRS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The photocatalytic efficiency of the Bi, N co-doped TiO2 treated at 600°C for 1 h was tested on the Indigo Carmine under the irradiation of visible light and compared with that of the commercial titanium oxide TiO2-P25 (Degussa). The XRD characterization of the material Bi -N- TiO2 (600°C) revealed the presence of the anatase phase and the absence of the rutile phase in comparison of the TiO2 P25 diffractogram. Characterization by UV- visible diffuse reflection (DRS) material showed that the Bi-N-TiO2 exhibits redshift (move visible) relative to commercial titanium oxide TiO2-P25, this property promises a photocatalytic activity of Bi-N-TiO2 under visible light. Indeed, the efficiency of photocatalytic Bi-N-TiO2 as a visible light is shown by a complete discoloration of indigo carmine solution of 16 mg/L after 40 minutes, whereas with the P25-TiO2 discoloration is achieved after 90 minutes.

Keywords: POA, heterogeneous photocatalysis, TiO2, co-doping

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Authors: Emmanuel Carlos De Mata Castrejón

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Music education has shown to be connected to many areas of sciences and arts, it has also been associated with several facets of human life. The many aspects around the study of music and education, make very difficult for the music educator to find a way through, even though there are lots of methods of teaching music to young children, they are different between one another and so are the students. For the music to help improve children’s development, it is necessary for the children to explore their musicality as they explore their creativity; it must be a challenging, playful, and enjoyable activity. The purpose of this investigation is to focus the music education not in the music, nor the teaching, but the children to be guided through their own musicality. The first approach to this kind of music education comes from the Active learning methods during the nineteenth century, most of which are still used around the world, sometimes with modifications to fit a certain place or type of students. This approach on children’s musicality requires some knowledge of music, pedagogy, and developmental psychology at least, but more important than the theory or the method used for music education, the focus should be on developing the student’s musicality, considering the complexity of this concept. To get this, it is needed, indeed, far more research in the topic, so this is a call for collaborative research and for interdisciplinary teams to emerge. This is a review of authors and methods in music education trying to trace a line pointing to transdisciplinary work and pursuing the development of children’s musicality.

Keywords: children, methods, music education, musicality

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Authors: Ashiraliyev SHavkat

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Relevance of the topic: Diabetes mellitus in overweight people development and absence of treatment measures. Objective: to give patients the correct instructions on proper nutrition, to organize a network of preventive and therapeutic measures. Materials and methods: Multidisciplinary Tashkent Medical Academy. As a result of objective observations in patients who applied to the clinic, 28 11 overweight patients had to type 2 diabetes. Diabetesmellituswasdiagnosed. Results: 11.5 mmol / L on an empty stomach in the morning. EDT yes. Pathogenesis: fat content in the diet of patients with diabetes mellitus. Carbohydrate foods make up 60%. Eating disorders and physical inactivity As a result, the accumulation of glucose in the form of fat increases, and this is constantly in the blood, which led to an increase in the number of fatty acids. Clinic: Frequent fasting in 11 patients (hypothalamus). Associated with glucose deficiency), drinking 8-9 liters of water per day of blood in 7 people Systolic pressure 150 diastolic pressures 100. Sensation of ants in 3 people and poor eyesight in 5 people. Conclusion: Explain to patients that nutritional guidelines should be followed. Assign active movement in accordance with the energy entering the body.

Keywords: mellitus, diabetes, pathogenesis, clinic

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Authors: Timothee Gidenne, Xia Pinqi

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In this paper, an investigation of the use of carbon nanotubes (CNTs) reinforced polymer as an actuator for an active flutter suppression to counter the flutter phenomena is conducted. The goal of this analysis is to establish a link between the behavior of the control surface and the actuators to demonstrate the veracity of using such a suppression system for the aeronautical field. A preliminary binary flutter model using simplified unsteady aerodynamics is developed to study the behavior of the wing while reaching the flutter speed and when the control system suppresses the flutter phenomena. The Timoshenko beam theory for bilayer materials is used to match the response of the control surface with the CNTs reinforced polymer (CNRP) actuators. According to Timoshenko theory, results show a good and realistic response for such a purpose. Even if the results are still preliminary, they show evidence of the potential use of CNRP for control surface actuation for the small-scale and lightweight system.

Keywords: actuators, aeroelastic, aeroservoelasticity, carbon nanotubes, flutter, flutter suppression

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Authors: Nabi Ullah

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The energy crisis of the current society has attracted research attention for alternative energy sources. Methanol oxidation is the source of energy but needs efficient electrocatalysts like Pt. However, their practical ability is hindered due to cost and poisoning effects. In this regard, an efficient catalyst is required for methanol oxidation. Herein, high temperature, pressure, and diethylenetryamine (DETA) as reaction medium/structure directing agent during the solvothermal method are used for nanobelt Cu₃Se₂/Cu₁.₈Se (mostly hexagonal appearance) formation. The electrocatalyst shows optimized methanol electrooxidation reaction (MOR) response in 1 M KOH and 0.5 M methanol at a scan rate of 50 mV/s and delivers a current density of 7.12 mA/mg at a potential of 0.65 V (vs Ag/AgCl). The catalyst exhibits high electrochemical active surface area (ECSA) (0.088 mF/cm²) and low Rct with good stability for 3600 s, which favors its high MOR performance. This high response is due to its 2D hexagonal nanobelt morphology, which provides a large surface area for reaction. The space among nanobelts reduces diffusion kinetics, and the rough/irregular edge increases the reaction site to improve the methanol oxidation reaction overall.

Keywords: energy application, electrocatalysis, MOR, nanobelt

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Authors: Abdur Rahim, Lauro Tatsuo Kubota, Yoshitaka Gushikem

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Carbon ceramic mesoporous SiO2/50wt%C (SBET= 170 m2g-1), where C is graphite, was prepared by the sol gel method. Scanning electron microscopy images and the respective element mapping showed that, within the magnification used, no phase segregation was detectable. It presented the electric conductivities of 0.49 S cm-1. This material was used to support cobalt phthalocyanine, prepared in situ, to assure a homogeneous dispersion of the electro active complex in the pores of the matrix. The surface density of cobalt phthalocyanine, on the matrix surfaces was 0.015 mol cm-2. Pressed disk, made with SiO2/50wt%C/CoPc, was used to fabricate an electrode and tested as sensors for nitrite determination by electro chemical technique. A linear response range between 0.039 and 0.42 mmol l−1,and correlation coefficient r=0.9996 was obtained. The electrode was chemically very stable and presented very high sensitivity for this analyte, with a limit of detection, LOD = 1.087 x 10-6 mol L-1.

Keywords: SiO2/C/CoPc, sol-gel method, electrochemical sensor, nitrite oxidation, carbon ceramic material, cobalt phthalocyanine

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Authors: Abigail Qian Zhou

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In recent years, the prosperity of mass tourism in China has accelerated the breadth and depth of direct communication between countries, and the national image has been placed in a new communication context. Outbound tourists are not only directly involved in the formation of the national image, but are also the most direct medium and the most active symbol representing the national image. This study uses Chinese middle-class tourists visiting Japan as a case study, and analyzes, through participant observation and semi-structured interviews, the communication function of the national image transmitted by 'human medium' in tourism activities. It also explores the 'human medium' in the era of mass tourism. This study hopes to build a bridge for tourism research and national image and media studies. It will provide a theoretical basis and practical guidance for promoting the national image, strengthening exchanges between tourists and local populations, and expanding the tourism market in the future.

Keywords: human medium, national image, communication, Chinese middle class, outbound tourists

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Authors: Jenifer Alam, Rima Chatterjee

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Upper Assam sedimentary basin is one of the oldest commercially producing basins of India. Being in a tectonically active zone, estimation of tectonic strain and stress magnitudes has vast application in hydrocarbon exploration and exploitation. This East North East –West South West trending shelf-slope basin encompasses the Bramhaputra valley extending from Mikir Hills in the southwest to the Naga foothills in the northeast. Assam Shelf lying between the Main Boundary Thrust (MBT) and Naga Thrust area is comparatively free from thrust tectonics and depicts normal faulting mechanism. The study area is bounded by the MBT and Main Central Thrust in the northwest. The Belt of Schuppen in the southeast, is bordered by Naga and Disang thrust marking the lower limit of the study area. The entire Assam basin shows low-level seismicity compared to other regions of northeast India. Pore pressure (PP), vertical stress magnitude (SV) and horizontal stress magnitudes have been estimated from two wells - N1 and T1 located in Upper Assam. N1 is located in the Assam gap below the Bramhaputra river while T1, lies in the Belt of Schuppen. N1 penetrates geological formations from top Alluvial through Dhekiajuli, Girujan, Tipam, Barail, Kopili, Sylhet and Langpur to the granitic basement while T1 in trusted zone crosses through Girujan Suprathrust, Tipam Suprathrust, Barail Suprathrust to reach Naga Thrust. Normal compaction trend is drawn through shale points through both wells for estimation of PP using the conventional Eaton sonic equation with an exponent of 1.0 which is validated with Modular Dynamic Tester and mud weight. Observed pore pressure gradient ranges from 10.3 MPa/km to 11.1 MPa/km. The SV has a gradient from 22.20 to 23.80 MPa/km. Minimum and maximum horizontal principal stress (Sh and SH) magnitudes under isotropic conditions are determined using poroelastic model. This approach determines biaxial tectonic strain utilizing static Young’s Modulus, Poisson’s Ratio, SV, PP, leak off test (LOT) and SH derived from breakouts using prior information on unconfined compressive strength. Breakout derived SH information is used for obtaining tectonic strain due to lack of measured SH data from minifrac or hydrofracturing. Tectonic strain varies from 0.00055 to 0.00096 along x direction and from -0.0010 to 0.00042 along y direction. After obtaining tectonic strains at each well, the principal horizontal stress magnitudes are calculated from linear poroelastic model. The magnitude of Sh and SH gradient in normal faulting region are 12.5 and 16.0 MPa/km while in thrust faulted region the gradients are 17.4 and 20.2 MPa/km respectively. Model predicted Sh and SH matches well with the LOT data and breakout derived SH data in both wells. It is observed from this study that the stresses SV>SH>Sh prevailing in the shelf region while near the Naga foothills the regime changes to SH≈SV>Sh area corresponds to normal faulting regime. Hence this model is a reliable tool for predicting stress magnitudes from well logs under active tectonic regime in Upper Assam Basin.

Keywords: Eaton, strain, stress, poroelastic model

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Authors: Mohd Adil, Rosina Khan, Asad U. Khan, Vasantha Rupasinghe HP

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The study examined the effects of Syzygium aromaticum extracts on the virulence properties of Streptococcus mutans. The activity of glucosyltransferases in the presence of crude and diethylether fraction was reduced to 80% at concentration 78.12μg/ml and 39.06μg/ml respectively. The glycolytic pH drop by S. mutans cells was also disrupted by these extracts without affecting the bacterial viability. Microscopic analysis revealed morphological changes of the S. mutans biofilms, indicating that these plant extracts at sub-MICs could significantly affect the ability of S. mutans to form biofilm with distorted extracellular matrix. Furthermore, with the help of quantitative RT-PCR, the expression of different genes involved in adherence, quorum sensing, in the presence of these extracts were down regulated. The crude and active fractions were found effective in preventing caries development in rats. The data showed that S. aromaticum holds promise as a naturally occurring source of compounds that may prevent biofilm-related oral diseases.

Keywords: biofilm, quorum sensing, Streptococcus mutans, Syzygium aromaticum extract

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Authors: Tarela J. Ike

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Over the years, the hemorrhagic acts of Boko Haram have led to the adoption of counter-terrorism measures which mostly takes the form of military repressive measures. These measures have wrought flagrant violation of human rights worthy of concern. Hence, the need to examine the efficacy of the counter-terrorism measures adopted by the Nigeria government in combatting terrorism. This article addresses this issue by relying on a systematic literature review which examines the impact of Nigeria counter-terrorism measures from 2009 to 2016 in combating terrorism. The review of literature includes 42 article. Of the 42 articles, 14 met the peer-reviewed requirement which finds that most of Nigeria’s counter-terrorism policies are geared toward the use of state repressive military approach which violates the human right. Thus, the study concludes that to effectively address the terrorist uprising; Nigeria should adopt a non-aggressive counter-terrorism approach which incorporates religious clerics, and community active engagement strategy in combatting terrorism as opposed to military retaliation which violates human right and so far proved ineffective.

Keywords: Boko Haram, counter-terrorism, human rights, military retaliation

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Authors: Pauline Ribert, Gaelle Roudaut, Sebastien Dupont, Laurent Beney

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Yeasts, anhydrobiotic organisms, can survive extreme water disturbances, thanks to the prolonged and reversible suspension of their cellular activity as well as the establishment of a defense arsenal. This property is exploited by many industrialists. One of the protection systems implemented by yeast is the vitrification of its cytoplasm by trehalose. The thermal resistance of dry yeasts is a crucial parameter for their use. However, studies on the thermal resistance of dry yeasts are often based on yeasts produced in laboratory conditions with non-optimal drying processes. We, therefore, propose a study on the thermal resistance of industrial dry yeasts in relation to their thermophysical properties. Heat stress was applied at three temperatures (50, 75, and 100°C) for 10, 30, or 60-minute treatments. The survival of yeasts to these treatments was estimated, and their thermophysical properties were studied by differential scanning calorimetry. The industrial dry yeasts resisted 60 minutes at 50°C and 75°C and 10 minutes at a temperature close to 100°C. At 100°C, yeast was above their glass transition temperature. Industrial dry yeasts are therefore capable of withstanding high thermal stress if maintained in a specific thermophysical state.

Keywords: dry yeast, glass transition, thermal resistance, vitrification

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Authors: Benjamin Kaufmann, Michael Hofstätter, Nadine Raidl, Peter Supancic

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ZnO varistors are the leading overvoltage protection elements in today’s electronic industry. Their highly non-linear current-voltage characteristics, very fast response times, good reliability and attractive cost of production are unique in this field. There are challenges and questions unsolved. Especially, the urge to create even smaller, versatile and reliable parts, that fit industry’s demands, brings manufacturers to the limits of their abilities. Although, the varistor effect of sintered ZnO is known since the 1960’s, and a lot of work was done on this field to explain the sudden exponential increase of conductivity, the strict dependency on sinter parameters, as well as the influence of the complex microstructure, is not sufficiently understood. For further enhancement and down-scaling of varistors, a better understanding of the microscopic processes is needed. This work attempts a microscopic approach to investigate ZnO varistor performance. In order to cope with the polycrystalline varistor ceramic and in order to account for all possible current paths through the material, a preferably realistic model of the microstructure was set up in the form of three-dimensional networks where every grain has a constant electric potential, and voltage drop occurs only at the grain boundaries. The electro-thermal workload, depending on different grain size distributions, was investigated as well as the influence of the metal-semiconductor contact between the electrodes and the ZnO grains. A number of experimental methods are used, firstly, to feed the simulations with realistic parameters and, secondly, to verify the obtained results. These methods are: a micro 4-point probes method system (M4PPS) to investigate the current-voltage characteristics between single ZnO grains and between ZnO grains and the metal electrode inside the varistor, micro lock-in infrared thermography (MLIRT) to detect current paths, electron back scattering diffraction and piezoresponse force microscopy to determine grain orientations, atom probe to determine atomic substituents, Kelvin probe force microscopy for investigating grain surface potentials. The simulations showed that, within a critical voltage range, the current flow is localized along paths which represent only a tiny part of the available volume. This effect could be observed via MLIRT. Furthermore, the simulations exhibit that the electric power density, which is inversely proportional to the number of active current paths, since this number determines the electrical active volume, is dependent on the grain size distribution. M4PPS measurements showed that the electrode-grain contacts behave like Schottky diodes and are crucial for asymmetric current path development. Furthermore, evaluation of actual data suggests that current flow is influenced by grain orientations. The present results deepen the knowledge of influencing microscopic factors on ZnO varistor performance and can give some recommendations on fabrication for obtaining more reliable ZnO varistors.

Keywords: metal-semiconductor contact, Schottky diode, varistor, zinc oxide

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Authors: Jorge Sandoval Lezama, Arturo Ivan Sandoval Rodriguez, Jose Arturo Correa Arredondo

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This work aims to share innovative educational experiences at IPN Mexico, that involve collaborative learning at institutional and global level through course competition and global collaboration projects. Students from universities in China, USA, South Korea, Canada and Mexico collaborate to design electric vehicles to solve global urban mobility problems. The participation of IPN students in the 2015-2016 global competition (São Paolo, Brazil and Cincinnati, USA) Reconfigurable Shared-Use Mobility Systems allowed to apply pedagogical strategies of groups of collaboration and of learning based on projects where they shared activities, commitments and goals, demonstrating that students were motivated to develop / self-generate their knowledge with greater meaning and understanding. One of the most evident achievements is that the students are self-managed, so the most advanced students train the students who join the project with CAD, CAE, CAM tools. Likewise, the motivation achieved is evident since in 2014 there were 12 students involved in the project, and there are currently more than 70 students.

Keywords: collaboration projects, global competency, course competition, active learning

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Authors: Salwa Mowafi, Mohamed Rehan, Hany Kafafy

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In this study, three different systems including room temperature, conventional water bath heating and microwave irradiation technique will be employed in the fabrication of silver nanoparticle-wool fibers. The silver nanoparticles will be synthesized in-situ incorporated into wool fibers under redox active bio-template of wool protein which facilitates the reduction of Ag+ to nanoparticulate Ag0. Silver NPs incorporated wool fiber will be characterized by scanning electron microscopy, energy dispersive X-ray, FTIR, TGA, silver content and X-ray photoelectron spectroscopy. The mechanism of binding Ag NPs in-situ incorporated wool fibers matrix will be discussed. The effect of silver nanoparticles on the coloration, antimicrobial, UV-protection and catalytic properties of the wool fibers will be evaluated. The overall results of this study indicate that the Ag NPs in-situ incorporated wool fibers will be applied as colorants for wool fibers with improving in its multi-functionality properties. So, this study provides a simple approach for innovative protein fibers design by applying the optical properties of Plasmonic noble metal nanoparticles.

Keywords: microwave irradiation technique, multi-functionality properties, silver nanoparticles, wool fibers

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Authors: Lalit Ahuja, Nancy Das, Yashas Shetty

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LED lighting has been increasingly adopted for vehicles in both domestic and foreign automotive markets. Although this miniaturized technology gives the best light output, low energy consumption, and cost-efficient solutions for driving, the same is the need of the hour. In this paper, we present a methodology for driving the highest class two-wheeler headlamp with regulator and rectifier (RR) output. Unlike usual LED headlamps, which are driven by a battery, regulator, and rectifier (RR) driven, a low-cost and highly efficient LED Driver Module (LDM) is proposed. The positive half of magneto output is regulated and used to charge batteries used for various peripherals. While conventionally, the negative half was used for operating bulb-based exterior lamps. But with advancements in LED-based headlamps, which are driven by a battery, this negative half pulse remained unused in most of the vehicles. Our system uses negative half-wave rectified DC output from RR to provide constant light output at all RPMs of the vehicle. With the negative rectified DC output of RR, we have the advantage of pulsating DC input which periodically goes to zero, thus helping us to generate a constant DC output equivalent to the required LED load, and with a change in RPM, additional active thermal bypass circuit help us to maintain the efficiency and thermal rise. The methodology uses the negative half wave output of the RR along with a linear constant current driver with significantly higher efficiency. Although RR output has varied frequency and duty cycles at different engine RPMs, the driver is designed such that it provides constant current to LEDs with minimal ripple. In LED Headlamps, a DC-DC switching regulator is usually used, which is usually bulky. But with linear regulators, we’re eliminating bulky components and improving the form factor. Hence, this is both cost-efficient and compact. Presently, output ripple-free amplitude drivers with fewer components and less complexity are limited to lower-power LED Lamps. The focus of current high-efficiency research is often on high LED power applications. This paper presents a method of driving LED load at both High Beam and Low Beam using the negative half wave rectified pulsating DC from RR with minimum components, maintaining high efficiency within the thermal limitations. Linear regulators are significantly inefficient, with efficiencies typically about 40% and reaching as low as 14%. This leads to poor thermal performance. Although they don’t require complex and bulky circuitry, powering high-power devices is difficult to realise with the same. But with the input being negative half wave rectified pulsating DC, this efficiency can be improved as this helps us to generate constant DC output equivalent to LED load minimising the voltage drop on the linear regulator. Hence, losses are significantly reduced, and efficiency as high as 75% is achieved. With a change in RPM, DC voltage increases, which can be managed by active thermal bypass circuitry, thus resulting in better thermal performance. Hence, the use of bulky and expensive heat sinks can be avoided. Hence, the methodology to utilize the unused negative pulsating DC output of RR to optimize the utilization of RR output power and provide a cost-efficient solution as compared to costly DC-DC drivers.

Keywords: class D LED headlamp, regulator and rectifier, pulsating DC, low cost and highly efficient, LED driver module

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Authors: Do Jaesoo, Kim Kyoung Seok

Abstract:

Under the recent difficult economic conditions, a number of people are increasingly expecting fostering ventures as the breakthrough in economic recovery and thus more attention is socially paid to an entrepreneur spirit. However, even though the role of managers is very important for the success of a venture company, programs to cultivate their qualities and skills are quite insufficient. In recent years, programs to foster entrepreneurs and business men have proliferated, which are led mainly by national agencies, research institutions, and large corporations. However, these programs still remain at a tottering stage, since there is no accumulated knowledge in many aspects, including systemic know-how and education. Therefore, this study attempted to introduce the definition of the entrepreneur (founder’s) spirit and furthermore identify the characteristics required for entrepreneurs as the subject of management. It thus tried to examine how those characteristics have an influence on entrepreneurs as their successful conditions, and presented foreign cases after analyzing the entrepreneur spirit through case studies. The entrepreneur spirit and the venture management emerge as a new field in business administration and scholars have reported various theories. Further research activities and efforts for active exchanges are also needed thereof.

Keywords: venture, entrepreneur, entrepreneur (founder’s) spirit, characteristics of entrepreneur spirit

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Authors: Hamidreza Heidari, Abdollah Malmir Nasab

Abstract:

In this paper, the energy equations of a two-link flexible manipulator were extracted using the Euler-Bernoulli beam hypotheses. Applying Assumed mode and considering some finite degrees of freedom, we could obtain dynamic motions of each manipulator using Euler-Lagrange equations. Using its claws, the robots can carry a certain load with the ached control of vibrations for robot flexible links during the travelling path using the piezoceramics transducer; dynamic load carrying capacity increase. The traveling path of flexible robot claw has been taken from that of equivalent rigid manipulator and coupled; therefore to avoid the role of Euler-Bernoulli beam assumptions and linear strains, material and physical characteristics selection of robot cause deflection of link ends not exceed 5% of link length. To do so, the maximum load carrying capacity of robot is calculated at the horizontal plan. The increasing of robot load carrying capacity with vibration control is 53%.

Keywords: flexible link, DLCC, active control vibration, assumed mode method

Procedia PDF Downloads 379

Authors: Francisco Ben, Tracey Price, Chad Morrison, Victoria Warren, Willy Gollan, Robyn Dunbar, Frank Davies, Mark Sorrell

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This paper focuses particularly on the educational aspects that contribute to the overall educational satisfaction rated by Tabor School of Education students who participated in the Australasian Survey of Student Engagement (AUSSE) conducted by the Australian Council for Educational Research (ACER) in 2010, 2012 and 2013. In all three years of participation, Tabor ranked first especially in the area of overall student satisfaction. By using a single level path analysis in relation to the AUSSE datasets collected using the Student Engagement Questionnaire (SEQ) for Tabor School of Education, seven aspects that contribute to overall student satisfaction have been identified. There appears to be a direct causal link between aspects of the Supportive Learning Environment, Work Integrated Learning, Career Readiness, Academic Challenge, and overall educational satisfaction levels. A further three aspects, being Student and Staff Interactions, Active Learning, and Enriching Educational Experiences, indirectly influence overall educational satisfaction levels.

Keywords: attrition, retention, educational experience, pre-service teacher education, student satisfaction

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Authors: Yiding Qu, Svetlana V. Komarova

Abstract:

Chemokines acting through their cognate chemokine receptors guide the directional migration of the cell along the chemokine gradient. Several chemokine receptors were recently identified as non-signaling (decoy), based on their ability to bind the chemokine but produce no measurable signal in the cell. The function of these decoy receptors is not well understood. We examined the expression of a decoy receptor CCRL1 and a signaling receptor that binds to the same ligands, CCR7, in prostate cancer using publically available microarray data (www.oncomine.org). The expression of both CCRL1 and CCR7 increased in an approximately half of prostate carcinoma samples and the majority of metastatic cancer samples compared to normal prostate. Moreover, the expression of CCRL1 positively correlated with the expression of CCR7. These data suggest that CCR7 and CCRL1 can be used as clinical markers for the early detection of transformation from carcinoma to metastatic cancer. In addition, these data support our hypothesis that the non-signaling chemokine receptors actively stimulate cell migration.

Keywords: bioinformatics, cell migration, decoy receptor, meta-analysis, prostate cancer

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Authors: Mehmet Salih Bayraktutan, Emre Tokmak

Abstract:

Great Ararat Volcano is the highest peak in South Caucasus Volcanic Plateau. Uplifted by Quaternary basaltic pyroclastic and lava flows. Numerous volcanic cones formed along with the tensional fractures under N-S compressional geodynamic framework. Basaltic flows have fresh surface morphology give ages of 650-680 K years. Hyperstene andesites constitute a major mass of Greater Ararat gives ages of 450-490 K years. During the early eruption period, predominately pyroclastics, cinder, lapilly-ash volcanic bombs were extruded. Third-period eruptions dominantly basaltic lava flows. Andesitic domes aligned along with the NW-SE striking fractures. Hyalo basalt and hornblende basaltic lavas are the latest lava eruptions. Hyalo-basaltic eruptions occurred via parasitic cones distributed far from the center. Parasitic cones are most common at the foot of Mount covered by recent NW flowing basaltic lava. Some of the cones are distributed on a circular pattern. One of the most hazardous disasters recorded in Eastern Turkey was July 1840 Cehennem Canyon Flood. Volcanic activities seismically triggered resulted in melting of glacier cap, mixed with ash and pyroclastics, flowed down along the Valley. Mud rich Slush urged catastrophically northwards, crossed Ars River and damned Surmeli Basin, forming reservoir behind. Ararat volcanoes are located on NW-SE striking Agri Fault Zone. Right lateral extensional faults, along which a series of andesitic domes formed. Great Ararat, in general strato-type volcano. This huge structure, developed in two main parts with different topographic and morphological features. The large lower base covers a widespread area composed of predominantly pyroclastics, ignimbrites, aglomerates, thick pumice, perlite deposits. Approximately 1/3 of the Crest by height formed of this basement. And 2/3 of the upper part with a conic- shape composed of basaltic lava flows. The active tectonic structure consists of three different patterns. The first network is radially distributed fractures formed during the last stage of lava eruptions. The second group of active faults striking in NW direction, and continue in N30W strike, formes Igdir Fault Zone. The third set of faults, dipping in the northwest with 75-80 degrees, strikes NE- SW across the whole Mount, slicing Great Ararat into four segments. In the upper stage of Cehennem Canyon, this set cutting volcanic layers caused numerous Waterfalls, Rock Avalanches, Mud Flows along the canyon, threatens the Village of Yanidogan, at the apex of flood deposits. Great Ararat Region has high seismo-tectonic risk and by occurrence frequency and magnitude, which caused in history caused heavy disasters, at villages surrounding the Ararat Basement.

Keywords: Eastern Turkey, geohazard, great ararat volcano, seismo-tectonic features

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Authors: N. Marzban, J. K. Heydarzadeh M. Pourmohammadbagher, M. H. Hatami, A. Samia

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A nano-alumina-zirconia composite catalyst was synthesized by a simple aqueous sol-gel method using AlCl₃.6H₂O and ZrCl₄ as precursors. Thermal decomposition of the precursor and subsequent formation of γ-Al₂O₃ and t-Zr were investigated by thermal analysis. XRD analysis showed that γ-Al₂O₃ and t-ZrO₂ phases were formed at 700 °C. FT-IR analysis also indicated that the phase transition to γ-Al₂O₃ occurred in corroboration with X-ray studies. TEM analysis of the calcined powder revealed that spherical particles were in the range of 8-12 nm. The nano-alumina-zirconia composite particles were mesoporous and uniformly distributed in their crystalline phase. In order to measure the catalytic activity, esterification reaction was carried out. Biodiesel, as a renewable fuel, was formed in a continuous packed column reactor. Free fatty acid (FFA) was esterified with ethanol in a heterogeneous catalytic reactor. It was found that the synthesized γ-Al₂O₃/ZrO₂ composite had the potential to be used as a heterogeneous base catalyst for biodiesel production processes.

Keywords: nano alumina-zirconia, composite catalyst, thin film, biodiesel

Procedia PDF Downloads 214