Search results for: solid state synthesis
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10786

Search results for: solid state synthesis

6166 Resting-State Functional Connectivity Analysis Using an Independent Component Approach

Authors: Eric Jacob Bacon, Chaoyang Jin, Dianning He, Shuaishuai Hu, Lanbo Wang, Han Li, Shouliang Qi

Abstract:

Objective: Refractory epilepsy is a complicated type of epilepsy that can be difficult to diagnose. Recent technological advancements have made resting-state functional magnetic resonance (rsfMRI) a vital technique for studying brain activity. However, there is still much to learn about rsfMRI. Investigating rsfMRI connectivity may aid in the detection of abnormal activities. In this paper, we propose studying the functional connectivity of rsfMRI candidates to diagnose epilepsy. Methods: 45 rsfMRI candidates, comprising 26 with refractory epilepsy and 19 healthy controls, were enrolled in this study. A data-driven approach known as independent component analysis (ICA) was used to achieve our goal. First, rsfMRI data from both patients and healthy controls were analyzed using group ICA. The components that were obtained were then spatially sorted to find and select meaningful ones. A two-sample t-test was also used to identify abnormal networks in patients and healthy controls. Finally, based on the fractional amplitude of low-frequency fluctuations (fALFF), a chi-square statistic test was used to distinguish the network properties of the patient and healthy control groups. Results: The two-sample t-test analysis yielded abnormal in the default mode network, including the left superior temporal lobe and the left supramarginal. The right precuneus was found to be abnormal in the dorsal attention network. In addition, the frontal cortex showed an abnormal cluster in the medial temporal gyrus. In contrast, the temporal cortex showed an abnormal cluster in the right middle temporal gyrus and the right fronto-operculum gyrus. Finally, the chi-square statistic test was significant, producing a p-value of 0.001 for the analysis. Conclusion: This study offers evidence that investigating rsfMRI connectivity provides an excellent diagnosis option for refractory epilepsy.

Keywords: ICA, RSN, refractory epilepsy, rsfMRI

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6165 Biomass Availability Matrix: Methodology to Define High Level Biomass Availability for Bioenergy Purposes, a Quebec Case Study

Authors: Camilo Perez Lee, Mark Lefsrud, Edris Madadian, Yves Roy

Abstract:

Biomass availability is one of the most important aspects to consider when determining the proper location of potential bioenergy plants. Since this aspect has a direct impact on biomass transportation and storage, biomass availability greatly influences the operational cost. Biomass availability is more than the quantity available on a specific region; other elements such as biomass accessibility and potential play an important role. Accessibility establishes if the biomass could be extracted and conveyed easily considering factors such as biomass availability, infrastructure condition and other operational issues. On the other hand, biomass potential is defined as the capacity of a specific region to scale the usage of biomass as an energy source, move from another energy source or to switch the type of biomass to increase their biomass availability in the future. This paper defines methodologies and parameters in order to determine the biomass availability within the administrative regions of the province of Quebec; firstly by defining the forestry, agricultural, municipal solid waste and energy crop biomass availability per administrative region, next its infrastructure accessibility and lastly defining the region potential. Thus, these data are processed to create a biomass availability matrix allowing to define the overall biomass availability per region and to determine the most optional candidates for bioenergy plant location.

Keywords: biomass, availability, bioenergy, accessibility, biomass potential

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6164 Development of Non-Point Pollutants Removal Equipments Using Media with Bacillus sp.

Authors: Han-Seul Lee, Min-Koo Kang, Sang-Ill Lee

Abstract:

This study was conducted to reduce runoff by rainwater infiltration facility using attached growth with Bacillus sp., which are reported to remove nitrogen and phosphorus, as well as organic matter effectively. This study was investigated non-point pollutants removal efficiency of organic, nitrogen, and phosphorus in column using the media attached growth with Bacillus sp. To compare attached growth with bacillus sp. and detached media, two columns filled with perlite, zeolite, vermiculite, pumice, peat-moss was installed. In A column (attached growth with bacillus sp.), in case of infiltration velocity 30 mm/hr in high concentration of influent, it showed the removal efficiency (after aging term) is SS (suspended solid) 85.8±1.2 %, T-P (total phosphorus) 67.0±8.1 %, T-N (total nitrogen) 66.0±4.9 %, COD (chemical oxygen demand) 73.6±2.9 %, NH4+-N 72.7±3.0 %. In B column (detached media), in case of infiltration velocity 30 mm/hr in high concentration of influent, it showed the removal efficiency (after aging term) is SS 86.0±2.2 %, T-P 62.5±11.3 %, T-N 53.3±3.9 %, COD 34.6±3.7 %, NH4+-N 61.5±2.8 %. Removal efficiency of A column is better than B column. As the result from this study, using media with Bacillus sp. can improve an effective removal of non-point source pollutants.

Keywords: non-point source pollutants, Bacillus sp., rainwater, infiltration facility

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6163 Isolation and Screening of Fungal Strains for β-Galactosidase Production

Authors: Parmjit S. Panesar, Rupinder Kaur, Ram S. Singh

Abstract:

Enzymes are the biocatalysts which catalyze the biochemical processes and thus have a wide variety of applications in the industrial sector. β-Galactosidase (E.C. 3.2.1.23) also known as lactase, is one of the prime enzymes, which has significant potential in the dairy and food processing industries. It has the capability to catalyze both the hydrolytic reaction for the production of lactose hydrolyzed milk and transgalactosylation reaction for the synthesis of prebiotics such as lactulose and galactooligosaccharides. These prebiotics have various nutritional and technological benefits. Although, the enzyme is naturally present in almonds, peaches, apricots and other variety of fruits and animals, the extraction of enzyme from these sources increases the cost of enzyme. Therefore, focus has been shifted towards the production of low cost enzyme from the microorganisms such as bacteria, yeast and fungi. As compared to yeast and bacteria, fungal β-galactosidase is generally preferred as being extracellular and thermostable in nature. Keeping the above in view, the present study was carried out for the isolation of the β-galactosidase producing fungal strain from the food as well as the agricultural wastes. A total of more than 100 fungal cultures were examined for their potential in enzyme production. All the fungal strains were screened using X-gal and IPTG as inducers in the modified Czapek Dox Agar medium. Among the various isolated fungal strains, the strain exhibiting the highest enzyme activity was chosen for further phenotypic and genotypic characterization. The strain was identified as Rhizomucor pusillus on the basis of 5.8s RNA gene sequencing data.

Keywords: beta-galactosidase, enzyme, fungal, isolation

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6162 Development of Mg-Containing Hydroxyapatite-Based Bioceramics From Phosphate Rock for Bone Applications

Authors: Sara Mercedes Barroso Pinzón, Álvaro Jesús Caicedo Castro, Antonio Javer Sánchez Herencia

Abstract:

In recent years there has been increased academic and industrial research into the development of orthopaedic implants with structural properties and functionality similar to mechanical strength, osseointegration, thermal stability and antibacterial capacity similar to bone structure. Hydroxyapatite has been considered for decades as an ideal biomaterial for bone regeneration due to its chemical and crystallographic similarity to the mineral structure bioapatites. However, the lack of trace elements in the hydroxyapatite structure confers very low mechanical and biological properties. Under this scenario, the objective of the research is the synthesis of hydroxyapatite with Mg from the francolite mineral present in phosphate rock from the central-eastern region of Colombia, taking advantage of the extraction of mineral species as natural precursors of Ca, P and Mg. The minerals present were studied, fluorapatite as the mineral of interest associated with magnesium carbonates and quartz. The chemical and mineralogical composition was determined by X-ray fluorescence (XRF) and X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX); the optimum conditions were established using the acid leaching mechanism in the wet concentration process. From the products obtained and characterised by XRD, XRF, SEM, FTIR, RAMAN, HAp-Mg biocomposite scaffolds are fabricated and the influence of Mg on morphometric parameters, mechanical and biological properties in the formed materials is evaluated.

Keywords: phosphate rock, hydroxyapatite, magnesium, biomaterials

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6161 The Virtues and Vices of Leader Empathy: A Review of a Misunderstood Construct

Authors: John G. Vongas, Raghid Al Hajj

Abstract:

In recent years, there has been a surge in research on empathy across disciplines ranging from management and psychology to philosophy and neuroscience. In organizational behavior, in particular, scholars have become interested in leader empathy given the rise of workplace diversity and the growing perception of leaders as managers of group emotions. It would appear that the current zeitgeist in behavioral and philosophical science is that empathy is a cornerstone of morality and that our world would be better off if only more people – and by extension, more leaders – were empathic. In spite of these claims, however, researchers have used different terminologies to explore empathy, confusing it at times with other related constructs such as emotional intelligence and compassion. Second, extant research that specifies what empathic leaders do and how their behavior affects organizational stakeholders, including themselves, does not devolve from a unifying theoretical framework. These problems plague knowledge development in this important research domain. Therefore, to the authors' best knowledge, this paper provides the first comprehensive review and synthesis of the literature on leader empathy by drawing on disparate yet complementary fields of inquiry. It clarifies empathy from other constructs and presents a theoretical model that elucidates the mechanisms by which a leader’s empathy translates into behaviors that could be either beneficial or harmful to the leaders themselves, as well as to their followers and groups. And third, it specifies the boundary conditions under which a leader’s empathy will become manifest. Finally, it suggests ways in which training could be implemented to improve empathy in practice while also remaining skeptical of its conceptualization as a moral or even effective guide in human affairs.

Keywords: compassion, empathy, leadership, group outcomes

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6160 A Review: Role of Chromium in Broiler

Authors: Naveed Zahra, Zahid Kamran, Shakeel Ahmad

Abstract:

Heat stress is one of the most important environmental stressors challenging poultry production worldwide. The detrimental effect of heat stress results in reduction in the productive performance of poultry with high incidences of mortality. Researchers have made efforts to prevent such damage to poultry production through dietary manipulation. Supplementation with Chromium (Cr) might have some positive effects on some aspect of blood parameters and broilers performance. Chromium (Cr) the element whose trivalent Cr (III) organic state is present in trace amounts in animal feed and water is found to be a key element in evading heat stress and thus cutting down the heavy expenditure on air conditioning in broiler sheds. Chromium, along with other essential minerals is lost due to increased excretion during heat stress and thus its inclusion in broiler diet is kind of mandatory in areas of hot climate. Chromium picolinate in broiler diet has shown a hike in growth rate including muscle gain with body fat reduction under environmental stress. Fat reduction is probably linked to the ability of chromium to increase the sensitivity of the insulin receptors on tissues and thus the uptake of sugar from blood increases which decreases the amount of glucose to be converted to amino acids and stored in adipose tissue as triglycerides. Organic chromium has also shown to increase lymphocyte proliferation rate and antioxidant levels. So, the immune competency, muscle gain and fat reduction along with evasion of heat stress are good enough signs that indicate the fruitful inclusion of dietary chromium for broiler. This promising element may bring the much needed break in the local poultry industry. The task is now to set the exact dose of the element in the diet that would be useful enough and still not toxic to broiler. In conclusion there is a growing body of evidence which suggest that chromium may be an essential trace element for livestock and poultry. The nutritional requirement for chromium may vary with different species and physiological state within a species.

Keywords: broiler, chromium, heat stress, performance

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6159 Synthesis of Tricalcium Phosphate Substituted with Magnesium Ions for Bone Regeneration

Authors: Andreia Cucuruz, Cristina Daniela Ghitulica, Georgeta Voicu, Cristina Busuioc

Abstract:

Ceramics based on calcium phosphates have lately increased attention for tissue engineering because they can be used as substitute bones or for bone regeneration since they mimic very well the nanostructure of tough bone tissue, but also because of other advantages such as a very good biocompatibility and osseointegration. This study aims the preparation and characterization of ceramic materials on the basis of TCP (Ca₃(PO₄)₂), within which calcium ions are substituted by magnesium ions (Mg²⁺) in order to improve the regenerative properties of these materials. TCP-Mg material was synthesized by chemical precipitation method using calcium oxide (CaO) and phosphoric acid (H₃PO₄) as precursors. The objective was to obtain powders with different concentrations of Mg in order to analyze the effect of magnesium ions on the physicochemical properties of phosphate ceramics and in vitro degradation in simulated biological fluid (SBF). Ceramic powders were characterized in vitro but also from the compositional and microstructural point of view. TCP_Mg powders were prepared through wet chemical method from calcium oxide (CaO), magnesium oxide nanopowder (MgO < 50 nm particle size (BET) Sigma Aldrich), phosphoric acid (H₃PO₄ - 85 wt.% in H₂O, 99.99% trace metals basis - Sigma Aldrich). In order to determine the quantities of raw materials, calculations were performed to obtain HAp with Ca/P ratio of 1.5.

Keywords: bone regeneration, magnesium substitution, tricalcium phosphate, tissue engineering

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6158 Assessment of Pull Mechanism at Enhancing Maize Farmers’ Utilisation of Aflasafe Bio-Control Measures in Oyo State, Nigeria

Authors: Jonathan A. Akinwale, Ibukun J. Agotola

Abstract:

There is a need to rethink how technology is being disseminated to end users in order to ensure wide adoption and utilisation. Aflasafe bio-control was developed to combat aflatoxin in maize to ensure food safety for the end users. This study was designed to assess how the pull mechanism is enhancing the utilisation of this proven technology among maize farmers in Oyo State, Nigeria. The study determines the awareness of farmers on Aflasafe, sources of purchase of Aflasafe, incentives towards the usage of Aflasafe, constraints to farmers’ utilisation and factors influencing farmers’ utilisation of Aflasafe bio-control measures. Respondents were selected using a multi-stage sampling procedure. Data were collected from respondents through interview schedule and analyzed using descriptive statistics (means, frequencies, and percentages) and inferential statistics (Pearson Product Moment Correlation and regression analysis). The result showed that 89% of the farmers indicated implementers as the outlet for the purchase of Aflasafe. Also, premium payment and provision of technical assistance were the highly ranked incentives to the utilisation of Aflasafe among the farmers. The study also revealed that the major constraints face by respondents were low access to credit facility, inadequate sources of purchase, and lack of storage facilities. A little above half (54%) of the farmers were found to have fully utilized Aflasafe in maize production. Pearson Product Moment Correlation (PPMC) analysis revealed that there was a significant correlation between incentives and utilisation of Aflasafe (r-value=0.274; p ≤ 0.01). The result of the regression analysis indicated maize production experience (β=0.572), output (β=0.531), years of formal education (β=0.404) and household size (β=0.391) as the leading factors influencing farmers utilisation of Aflasafe bio-control in maize production. The study, therefore, recommends that governments and non-governmental organisations should be interested in making Aflasafe available to the maize farmers either through loan provision or price subsidy.

Keywords: Aflasafe bio-control, maize production, production incentives, pull mechanism, utilisation

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6157 A Nonlinear Visco-Hyper Elastic Constitutive Model for Modelling Behavior of Polyurea at Large Deformations

Authors: Shank Kulkarni, Alireza Tabarraei

Abstract:

The fantastic properties of polyurea such as flexibility, durability, and chemical resistance have brought it a wide range of application in various industries. Effective prediction of the response of polyurea under different loading and environmental conditions necessitates the development of an accurate constitutive model. Similar to most polymers, the behavior of polyurea depends on both strain and strain rate. Therefore, the constitutive model should be able to capture both these effects on the response of polyurea. To achieve this objective, in this paper, a nonlinear hyper-viscoelastic constitutive model is developed by the superposition of a hyperelastic and a viscoelastic model. The proposed constitutive model can capture the behavior of polyurea under compressive loading conditions at various strain rates. Four parameter Ogden model and Mooney Rivlin model are used to modeling the hyperelastic behavior of polyurea. The viscoelastic behavior is modeled using both a three-parameter standard linear solid (SLS) model and a K-BKZ model. Comparison of the modeling results with experiments shows that Odgen and SLS model can more accurately predict the behavior of polyurea. The material parameters of the model are found by curve fitting of the proposed model to the uniaxial compression test data. The proposed model can closely reproduce the stress-strain behavior of polyurea for strain rates up to 6500 /s.

Keywords: constitutive modelling, ogden model, polyurea, SLS model, uniaxial compression test

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6156 An Electrode Material for Ultracapacitors: Hydrothermal Synthesis of Neodymium Oxide/Manganese Oxide/Nitrogen Doped Reduced Graphene Oxide Ternary Nanocomposites

Authors: K. Saravanan, K. A.Rameshkumar, P. Maadeswaran

Abstract:

The depletion of fossil resources and the rise in global temperatures are two of the most important concerns we confront today. There are numerous renewable energy sources like solar power, tidal power, wind energy, radiant energy, hydroelectricity, geothermal energy, and biomass available to generate the needed energy demand. Engineers and scientists around the world are facing a massive barrier in the development of storage technologies for the energy developed from renewable energy sources. The development of electrochemical capacitors as a future energy storage technology is at the forefront of current research and development. This is due to the fact that the electrochemical capacitors have a significantly higher energy density, a faster charging-discharging rate, and a longer life span than capacitors, and they also have a higher power density than batteries, making them superior to both. In this research, electrochemical capacitors using the Nd2O3/Mn3O4/ N-rGO electrode material is chosen since the of hexagonal and tetragonal crystal structures of Nd2O3 and Mn3O4 and also has cycling stability of 68% over a long time at 50mVs-1 and a high coulombic efficiency of 99.64% at 5 Ag-1. This approach may also be used to create novel electrode materials with improved electrochemical and cyclic stability for high-performance supercapacitors.

Keywords: Nd2O3/Mn3O4/N-rGO, nanocomposites, hydrothermal method, electrode material, specific capacitance, use of supercapacitors

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6155 Dynamics of Agricultural Information and Effect on Income of Melon Farmers in Enugu Ezike Agricultural Zone of Enugu State, Nigeria

Authors: Iwuchukwu J. C., Ekeh G. Madukwe, M. C., Asadu A. N.

Abstract:

Melon has significant importance of easy to plant, early maturing, low nutrient requirement and high yielding. Yet many melon farmers in the study area are either diversifying or abandoning this enterprise probably because of lack of agricultural knowledge/information and consequent reduction in output and income. The study was therefore carried out to asses effects of agricultural information on income of melon farmers in Enugu-Ezike Agricultural zone of Enugu state, Nigeria. Three blocks, nine circles and ninety melon farmers who were purposively selected constituted the sample for the study..Data were collected with interview schedule. Percentage and chart were used to present some of the data while some were analysed with mean score and correlation. The findings reveal that. average annual income of these respondents from melon was about seven thousand and five hundred Naira (approximately forty five Dollars). while their total average monthly income (income from melon and other sources) was about one thousand and two hundred Naira (approximately seven Dollars). About 42.% and 62% of the respondents in their respective order did not receive information on agricultural matters and melon production. Among the minority that received information on melon production, most of them sourced it from neighbours/friends/relatives. Majority of the respondents needed information on how to plant melon through interpersonal contact (face to face) using Igbo language as medium of communication and extension agent as teacher or resource person. The study also reveal a significant and positive relationship between number of times respondents received information on agriculture and their total monthly income. There was also a strong, positive and significant relationship between number of times respondents received information on melon and their annual income on melon production. The study therefore recommends that governmental and non-governmental organizations/ institutions should strengthen these farmers access to information on agriculture and melon specifically so as to boost their output and income.

Keywords: farmers, income, information, melon

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6154 Caecotrophy Behaviour of the Rabbits (Oryctolagus cuniculus)

Authors: Awadhesh Kishore

Abstract:

One of the most unique characteristics of rabbit feeding behaviour is caecotrophy, which involves the excretion and immediate consumption of specific faeces known as soft faeces. Caecotrophy in rabbits is the instinctual behaviour of eating soft faeces; reduced caecotrophy decreases rabbit growth and lipid synthesis in the liver. Caecotroph ingestion is highest when rabbits are fed a diet high in indigestible fibre. The colon produces two types of waste: hard and soft pellets. The hard pellets are expelled, but the soft pellets are re-ingested by the rabbit directly upon being expelled from the anus by twisting itself around and sucking in those pellets as they emerge from the anus. The type of alfalfa hay in the feed of the rabbits does not affect volatile fatty acid concentration, the pattern of fermentation, or pH in the faeces. The cecal content and the soft faeces contain significant amounts of retinoids and carotenoids, while in the tissues (blood, liver, and kidney), these pigments do not occur in substantial amounts. Preventing caecotrophy reduced growth and altered lipid metabolism, depressing the development of new approaches for rabbit feeding and production. Relative abundance is depressed for genes related to metabolic pathways such as vitamin C and sugar metabolism, vitamin B2 metabolism, and bile secretion. The key microorganisms that regulate the rapid growth performance of rabbits may provide useful references for future research and the development of microecological preparations.

Keywords: caecocolonic microorganisms, caecotrophy, fasting caecotrophy, rabbits, soft pellets

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6153 A Review of Hypnosis Uses for Anxiety and Phobias Treatment

Authors: Fleura Shkëmbi, Sevim Mustafa, Naim Fanaj

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Hypnosis, often known as cognitive therapy, is a sort of mind-body psychotherapy. A professional and certified hypnotist or hypnotherapist guides the patient into this extreme level of focus and relaxation during the session by utilizing verbal cues, repetition, and imagery. In recent years, hypnotherapy has gained popularity in the treatment of a variety of disorders, including anxiety and particular phobias. The term "phobia" is commonly used to define fear of a certain trigger. When faced with potentially hazardous situations, the brain naturally experiences dread. While a little dread here and there may keep us safe, phobias can drastically reduce our quality of life. In summary, persons who suffer from anxiety are considered to see particular environmental situations as dangerous, but those who do not suffer from anxiety do not. Hypnosis is essential in the treatment of anxiety disorders. Hypnosis can help patients minimize their anxiety symptoms. This broad concept has aided in the development of models and therapies for anxiety disorders such as generalized anxiety disorder, panic attacks, hypochondria, and obsessional disorders. Hypnosis techniques are supposed to be attentive and mental pictures, which is conceivable; this is why they're associated with improved working memory and visuospatial abilities. In this sense, the purpose of this study is to determine how effectively specific therapeutic methods perform in treating persons with anxiety and phobias. In addition to cognitive-behavioral therapy and other therapies, the approaches emphasized the use of therapeutic hypnosis. This study looks at the use of hypnosis and related psychotherapy procedures in the treatment of anxiety disorders. Following a discussion of the evolution of hypnosis as a therapeutic tool, neurobiological research is used to demonstrate the influence of hypnosis on the change of perception in the brain. The use of hypnosis in the treatment of phobias, stressful situations, and posttraumatic stress disorder is examined, as well as similarities between the hypnotic state and dissociative reactions to trauma. Through an extensive literature evaluation, this study will introduce hypnotherapy procedures that result in more successful anxiety and phobia treatment.

Keywords: anxiety, hypnosis, hypnotherapy, phobia, technique, state

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6152 Provision of Slope Stability with Barette Piles: A Case Analysis

Authors: Leyla Yesilbas, M. Sukru Ozcoban, M. Ergenekon Selcuk

Abstract:

From past to present, there is a constant need for engineering structures such as high-rise buildings, wide-span bridges, airports and stadiums, business towers due to technological developments and increasing population. Because of the large loads transferred from the superstructure to the ground layers in these types of structures, the bearing strength and seating problems usually occur on the floors. In order to solve these problems, piled foundations are used by passing the weak soil layers and transferring the loads from the superstructure to the solid soil layers. Considering the factors such as the characteristics of the building to be constructed, the purpose and location of the building, the basic cost of the pile should be at normal levels. When these requirements are taken into consideration, a new basic system called 'Barette Foundation' has been developed. In this thesis, an application made to provide slope stability with 'Baret Piles' was investigated. In addition, the ground parameters obtained from the field and laboratory experiments were numerically modeled using a PLAXİS 2D finite element software and barette piles. The effects of barette piles on slope stability were investigated by numerical analysis, and the results of inclinometer measurements in the field were compared with numerical analysis results.

Keywords: barette pile, PLAXİS 2D, slope, soil

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6151 Geomorphometric Analysis of the Hydrologic and Topographic Parameters of the Katsina-Ala Drainage Basin, Benue State, Nigeria

Authors: Oyatayo Kehinde Taofik, Ndabula Christopher

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Drainage basins are a central theme in the green economy. The rising challenges in flooding, erosion or sediment transport and sedimentation threaten the green economy. This has led to increasing emphasis on quantitative analysis of drainage basin parameters for better understanding, estimation and prediction of fluvial responses and, thus associated hazards or disasters. This can be achieved through direct measurement, characterization, parameterization, or modeling. This study applied the Remote Sensing and Geographic Information System approach of parameterization and characterization of the morphometric variables of Katsina – Ala basin using a 30 m resolution Shuttle Radar Topographic Mission (SRTM) Digital Elevation Model (DEM). This was complemented with topographic and hydrological maps of Katsina-Ala on a scale of 1:50,000. Linear, areal and relief parameters were characterized. The result of the study shows that Ala and Udene sub-watersheds are 4th and 5th order basins, respectively. The stream network shows a dendritic pattern, indicating homogeneity in texture and a lack of structural control in the study area. Ala and Udene sub-watersheds have the following values for elongation ratio, circularity ratio, form factor and relief ratio: 0.48 / 0.39 / 0.35/ 9.97 and 0.40 / 0.35 / 0.32 / 6.0. They also have the following values for drainage texture and ruggedness index of 0.86 / 0.011 and 1.57 / 0.016. The study concludes that the two sub-watersheds are elongated, suggesting that they are susceptible to erosion and, thus higher sediment load in the river channels, which will dispose the watersheds to higher flood peaks. The study also concludes that the sub-watersheds have a very coarse texture, with good permeability of subsurface materials and infiltration capacity, which significantly recharge the groundwater. The study recommends that efforts should be put in place by the Local and State Governments to reduce the size of paved surfaces in these sub-watersheds by implementing a robust agroforestry program at the grass root level.

Keywords: erosion, flood, mitigation, morphometry, watershed

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6150 Investigating the Nature of Transactions Behind Violations Along Bangalore’s Lakes

Authors: Sakshi Saxena

Abstract:

Bangalore is an IT industry-based metropolitan city in the state of Karnataka in India. It has experienced tremendous urbanization at the expense of the environment. The reasons behind development over and near ecologically sensitive areas have been raised by several instances of disappearing lakes. Lakes in Bangalore can be considered commons on both a local and a regional scale and these water bodies are becoming less interconnected because of encroachment in the catchment area. Other sociocultural environmental risks that have led to social issues are now a source of concern. They serve as an example of the transformations in commons, a dilemma that as is transformed from rural to urban areas, as well as the complicated institutional issues associated with governance. According to some scholarly work and ecologists, a nexus of public and commercial institutions is primarily responsible for the depletion of water tanks and the inefficiency of the planning process. It is said that Bangalore's growth as an urban centre, together with the demands it created, particularly on land and water, resulted in the emergence of a middle and upper class that was demanding and self-assured. For the report in focus, it is evident to understand the issues and problems which led to these encroachments and captured violations if any around these lakes and tanks which arose during these decades. To claim watersheds and lake edges as properties, institutional arrangements (organizations, laws, and policies) intersect with planning authorities. Because of unregulated or indiscriminate forms of urbanization, it is claimed that the engagement of actors and negotiations of the process, including government ignorance, are allowing this problem to flourish. In general, the governance of natural resources in India is largely state-based. This is due to the constitutional scheme, which since the Government of India Act, of 1935 has in principle given the power to the states to legislate in this area. Thus, states have the exclusive power to regulate water supplies, irrigation and canals, drainage and embankments, water storage, hydropower, and fisheries. Thus, The main aim is to understand institutional arrangements and the master planning processes behind these arrangements. To understand the ambiguity through an example, it is noted that, Custodianship alone is a role divided between two state and two city-level bodies. This creates regulatory ambiguity and the effects on the environment are such as changes in city temperature, urban flooding, etc. As established, the main kinds of issues around lakes/tanks in Bangalore are encroachment and depletion. This study will further be enhanced by doing a physical survey of three of these lakes focusing on the Bellandur site and the stakeholders involved. According to the study's findings thus far, corrupt politicians and dubious land transaction tools are involved in the real estate industry. It appears that some destruction could have been stopped or at least mitigated in this case if there had been a robust system of urban planning processes involved along with strong institutional arrangements to protect lakes.

Keywords: wetlands, lakes, urbanization, bangalore, politics, reservoirs, municipal jurisdiction, lake connections, institutions

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6149 Fabrication and Characterization of PPy/rGO|PPy/ZnO Composite with Varying Zno Concentration as Anode for Fuel Cell Applications

Authors: Bryan D. Llenarizas, Maria Carla F. Manzano

Abstract:

The rapid growth of electricity demand has led to a pursuit of alternative energy sources with high power output and not harmful to the environment. The fuel cell is a device that generates electricity via chemical reactions between the fuel and oxidant. Fuel cells have been known for decades, but the development of high-power output and durability was still one of the drawbacks of this energy source. This study investigates the potential of layer-by-layer composite for fuel cell applications. A two-electrode electrochemical cell was used for the galvanostatic electrochemical deposition method to fabricate a Polypyrrole/rGO|Polypyrrole/ZnO layer-by-layer composite material for fuel cell applications. In the synthesis, the first layer comprised 0.1M pyrrole monomer and 1mg of rGO, while the second layer had 0.1M pyrrole monomer and variations of ZnO concentration ranging from 0.08M up to 0.12M. A constant current density of 8mA/cm² was applied for 1 hour in fabricating each layer. Scanning electron microscopy (SEM) for the fabricated LBL material shows a globular surface with white spots. These white spots are the ZnO particles confirmed by energy-dispersive X-ray spectroscopy, indicating a successful deposition of the second layer onto the first layer. The observed surface morphology was consistent for each variation of ZnO concentrations. AC measurements were conducted to obtain the AC resistance of the fabricated film. Results show a decrease in AC resistance as the concentration of ZnO increases.

Keywords: anode, composite material, electropolymerization, fuel cell, galvanostatic, polypyrrole

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6148 The Arabic Literary Text, between Proficiency and Pedagogy

Authors: Abdul Rahman M. Chamseddine, Mahmoud El-ashiri

Abstract:

In the field of language teaching, communication skills are essential for the learner to achieve, however, these skills, in general, might not support the comprehension of some texts of literary or artistic nature like poetry. Understanding sentences and expressions is not enough to understand a poem; other skills are needed in order to understand the special structure of a text which literary meaning is inapprehensible even when the lingual meaning is well comprehended. And then there is the need for many other components that surpass one text to other similar texts that can be understood through solid traditions, which do not form an obstacle in the face of change and progress. This is not exclusive to texts that are classified as a literary but it is also the same with some daily short phrases and indicatively charged expressions that can be classified as literary or bear a taste of literary nature.. it can be found in Newpapers’ titles, TV news reports, and maybe football commentaries… the need to understand this special lingual use – described as literary – is highly important to understand this discourse that can be generally classified as very far from literature. This work will try to explore the role of the literary text in the language class and the way it is being covered or dealt with throughout all levels of acquiring proficiency. It will also attempt to survery the position of the literary text in some of the most important books for teaching Arabic around the world. The same way grammar is needed to understand the language, another (literary) grammar is also needed for understanding literature.

Keywords: language teaching, Arabic, literature, pedagogy, language proficiency

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6147 Critical Analysis of the Caspian: The Role of Identity in Russia's Foreign Policy

Authors: Aidana Arynbek

Abstract:

This paper attempts to offer an alternative to the explanation of the politics of great powers in Caspian politics. Since many researchers have analysed the politics of great powers in the region with the focus on materialism, this paper attempts to bring a sociological inquiry into analysing inter-state behaviour. The constructivist concept of Alexander Wendt will be applied to analyse Russia’s relation with The United States, China and Iran; the main argument is emphasis on the power of ideational forces over material ones. Moreover, the innovative contribution of Wendt regarding the understanding of anarchy to the study of International Relations (IR) will be applied; in his words, ‘anarchy is what states make of it’. A neo-realist perspective implies that with the structure of international politics, Russia treats all great powers as rivals through engagement in power politics; however, Wendt’s approach is able to explain the reason behind the state’s behaviour towards power politics, and this is about not only international structure, but also identity. The understanding of identity answers the question of how Russia came about to follow different actions in relation to Iran and China in contrast to The United States. This paper will be divided into five chapters. The first chapter will explain the constructivism of Alexander Wendt; the second chapter will give a brief background to The Caspian Sea Region (CSR); the third chapter will explain the formation of Russia’s identity towards The United States, and this will be applied to analyse Russia’s relation to The U.S in The CSR. Similarly with China, the fourth chapter will explain Russia’s identity and its relations in The CSR, and finally, the fifth chapter will show Russia’s identity towards Iran and its relation to Iran in The CSR. It will be concluded that the analysis of the politics between great powers in seeking to access one of the richest regions, The Caspian Basin, will show that international politics is not fixed, but constructed by human action and cognition. Reality in the politics of great powers in The Caspian Sea Region is socially constructed. This paper is not interested in how things are, but how they became what they are. That is to say, how Russia’s foreign policies towards great powers became what they are.

Keywords: Alexander Wendt, Caspian sea, identity, Russia, socially constructed

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6146 Long-Term Deformations of Concrete Structures

Authors: Abdelmalk Brahma

Abstract:

Drying is a phenomenon that accompanies the hardening of hydraulic materials. It can, if it is not prevented, lead to significant spontaneous dimensional variations, which the cracking is one of events. In this context, cracking promotes the transport of aggressive agents in the material, which can affect the durability of concrete structures. Drying shrinkage develops over a long period almost 30 years although most occurred during the first three years. Drying shrinkage stabilizes when the material is water balance with the external environment. The drying shrinkage of cementitious materials is due to the formation of capillary tensions in the pores of the material, which has the consequences of bringing the solid walls of each other. Knowledge of the shrinkage characteristics of concrete is a necessary starting point in the design of structures for crack control. Such knowledge will enable the designer to estimate the probable shrinkage movement in reinforced or prestressed concrete and the appropriate steps can be taken in design to accommodate this movement. This study is concerned the modelling of drying shrinkage of the hydraulic materials and the prediction of the rate of spontaneous deformations of hydraulic materials during hardening. The model developed takes in consideration the main factors affecting drying shrinkage. There was agreement between drying shrinkage predicted by the developed model and experimental results. In last we show that developed model describe the evolution of the drying shrinkage of high performances concretes correctly.

Keywords: drying, hydraulic concretes, shrinkage, modeling, prediction

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6145 Impact of Green Bonds Issuance on Stock Prices: An Event Study on Respective Indian Companies

Authors: S. L. Tulasi Devi, Shivam Azad

Abstract:

The primary objective of this study is to analyze the impact of green bond issuance on the stock prices of respective Indian companies. An event study methodology has been employed to study the effect of green bond issuance. For in-depth study and analysis, this paper used different window frames, including 15-15 days, 10-10 days, 7-7days, 6-6 days, and 5-5 days. Further, for better clarity, this paper also used an uneven window period of 7-5 days. The period of study covered all the companies which issued green bonds during the period of 2017-2022; Adani Green Energy, State Bank of India, Power Finance Corporation, Jain Irrigation, and Rural Electrification Corporation, except Indian Renewable Energy Development Agency and Indian Railway Finance Corporation, because of data unavailability. The paper used all three event study methods as discussed in earlier literature; 1) constant return model, 2) market-adjusted model, and 3) capital asset pricing model. For the fruitful comparison between results, the study considered cumulative average return (CAR) and buy and hold average return (BHAR) methodology. For checking the statistical significance, a two-tailed t-statistic has been used. All the statistical calculations have been performed in Microsoft Excel 2016. The study found that all other companies have shown positive returns on the event day except for the State Bank of India. The results demonstrated that constant return model outperformed compared to the market-adjusted model and CAPM. The p-value derived from all the methods has shown an almost insignificant impact of the issuance of green bonds on the stock prices of respective companies. The overall analysis states that there’s not much improvement in the market efficiency of the Indian Stock Markets.

Keywords: green bonds, event study methodology, constant return model, market-adjusted model, CAPM

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6144 Challenges and Prospects of Digital Economy Development in Georgia

Authors: Gulnaz Erkomaishvili

Abstract:

Introduction: There are some of the biggest technological shifts happening in the modern world. The introduction of digital technologies, information, and communication services has given rise to unprecedented global socio-political and economic changes. The role of digital technologies in increasing productivity and national competitiveness is increasing. Today, it is used in almost every area of the economy. E-commerce, organizational process in computerized management, and digital infrastructure's pace of growth is remarkably high and is a key instrument of economic development. Methodology: Different research methods are applied in the presented paper; statistical, analysis, synthesis, induction, deduction, comparison ones. Works by local and foreign scientists, Ministry of Economy and Sustainable Development, as well as various organizations' studies and reports were used as a theoretical basis for research and variety of laws, government decrees and orders, and the publications of the National Statistics Office of Georgia were used as an informational basis. Conclusions: The paper deals with the processes and challenges in Georgia in the digital economy. Access to current resources in Georgia and current processes are described. Digital technology for the development of the required environmental conditions is described, how the Internet and communications are available for the population in the regions of Georgia. The pros and cons of the digital economy development and its impact on the country's economy are analyzed. The main difficulties of implementation of the digital economy in Georgia, government involvement, and future action plans are presented.

Keywords: digital economy, digital technologies, internet, communications, economic policy

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6143 Gentrification in Istanbul: The Twin Paradox

Authors: Tugce Caliskan

Abstract:

The gentrification literature in Turkey provided important insights regarding the analysis of the socio-spatial change in İstanbul mostly through the existing gentrification theories which were produced in Anglo-American literature. Yet early researches focused on the classical gentrification while failing to notice other place-specific forms of the phenomena. It was only after the mid-2000s that scholarly attention shifted to the recent discussions in the mainstream such as the neoliberal urban policies, government involvement, and resistance. Although these studies have considerable potential to contribute to the geography of gentrification, it seems that copying the linear timeline of Anglo-American conceptualization limited the space to introduce contextually nuanced way of process in Turkey. More specifically, the gentrification literature in Turkey acknowledged the linear timeline of the process drawing on the mainstream studies, and, made the spontaneous classical gentrification as the starting point in İstanbul at the expense of contextually specific forms of the phenomenon that took place in the same years. This paper is an attempt to understand place-specific forms of gentrification through the abandonment of the linear understanding of time. In this vein, this paper approaches the process as moving both linear and cyclical rather than the waves succeeded each other. Maintaining a dialectical relationship between the cyclical and the linear time, this paper investigates how the components of gentrification have been taken place in the cyclical timeline while becoming bolder in the linear timeline. This paper argues that taking the (re)investment in the secondary circuit of capital and class transformation as the core characteristics of gentrification, and accordingly, searching for these components beyond the linear timeline provide strategic value to decenter the perspectives, not merely for Turkish studies. In this vein, this strategy revealed that Western experience of gentrification did not travel, adopted or copied in Turkey but gentrification -as an abstract and general concept- has emerged as a product of different contextual, historical and temporal forces which must be considered within the framework of state-led urbanization as early as 1980 differing from the Global North trajectories.

Keywords: comparative urbanism, geography of gentrification, linear and cyclical timeline, state-led gentrification

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6142 Combating the Practice of Open Defecation through Appropriate Communication Strategies in Rural India

Authors: Santiagomani Alex Parimalam

Abstract:

Lack of awareness on the consequences of open defecation and myths and misconceptions related to use of toilets have led to the continued practice of open defecation in India. Government of India initiated a multi-pronged intensive communication campaign against the practice of open defecation in the last few years. The primary vision of this communication campaign was to provide increased demand for toilets and to ensure that all have access to safe sanitation. The campaign strategy included the use of mass media, group and folk media, and interpersonal communication to expedite achieving its objectives. The campaign included the use of various media such as posters, wall writings, slides in cinema theatres, kiosks, pamphlets, newsletters, flip charts and folk media to bring behavioural changes in the communities. The author did a concurrent monitoring and process documentation of the campaigns initiated by the state of Tamilnandu, India between 2013 and 2016 commissioned by UNICEF India. The study was carried out to assess the effectiveness of the communication campaigns in combating the practice of open defecation and promote construction of toilets in the state of Tamilnadu, India. Initial findings revealed the gap in understanding the audience and the use of appropriate media. The first phase of the communication campaign by name as Chi Chi Chollapa (bringing shame concept) also revealed that use of interpersonal communication, group and community media were the most effective strategy in reaching the rural masses. The failure of various other media used especially the print media (poster, handbills, newsletter, kiosks) provides insights as to where the government needs to invest its resources in bringing health-seeking behaviour in the community. The findings shared with the government enabled to strengthen the campaign resulting in improved response. Taking cues from the study, the government understood the potency of the women, school children, youth and community leaders as the effective carriers of the message. The government narrowed down its focus and invested on the voluntary workers (village poverty reduction committee workers VPRCs) in the community. The effectiveness of interpersonal communication and peer education by the credible community worker threw light on the need for localising the content and communicator. From this study, we could derive that only community and group media are preferred by the people in the rural community. Children, youth, women, and credible local leaders are proved to be ambassadors in behaviour change communication. This study discloses the lacunae involved in the communication campaign and points out that the state should have carried out a proper communication need analysis and piloting. The study used a survey method with random sampling. The study used both quantitative and qualitative tools such as interview schedules, in-depth interviews, and focus group discussions in rural areas of Tamilnadu in phases. The findings of the study would provide directions to future campaigns to any campaign concerning health and rural development.

Keywords: appropriate, communication, combating, open defecation

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6141 A New Realization of Multidimensional System for Grid Sensor Network

Authors: Yang Xiong, Hua Cheng

Abstract:

In this paper, for the basic problem of wireless sensor network topology control and deployment, the Roesser model in rectangular grid sensor networks is presented. In addition, a general constructive realization procedure will be proposed. The procedure enables a distributed implementation of linear systems on a sensor network. A non-trivial example is illustrated.

Keywords: grid sensor networks, Roesser model, state-space realization, multidimensional systems

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6140 Correlates of Income Generation of Small-Scale Fish Processors in Abeokuta Metropolis, Ogun State, Nigeria

Authors: Ayodeji Motunrayo Omoare

Abstract:

Economically fish provides an important source of food and income for both men and women especially many households in the developing world and fishing has an important social and cultural position in river-rine communities. However, fish is highly susceptible to deterioration. Consequently, this study was carried out to correlate income generation of small-scale women fish processors in Abeokuta metropolis, Ogun State, Nigeria. Eighty small-scale women fish processors were randomly selected from five communities as the sample size for this study. Collected data were analyzed using both descriptive and inferential statistics. The results showed that the mean age of the respondents was 31.75 years with average household size of 4 people while 47.5% of the respondents had primary education. Most (86.3%) of the respondents were married and had spent more than 11 years in fish processing. The respondents were predominantly Yoruba tribe (91.2%). Majority (71.3%) of the respondents used traditional kiln for processing their fish while 23.7% of the respondents used hot vegetable oil to fry their fish. Also, the result revealed that respondents sourced capital from Personal Savings (48.8%), Cooperatives (27.5%), Friends and Family (17.5%) and Microfinance Banks (6.2%) for fish processing activities. The respondents generated an average income of ₦7,000.00 from roasted fish, ₦3,500.00 from dried fish, and ₦5,200.00 from fried fish daily. However, inadequate processing equipment (95.0%), non-availability of credit facility from microfinance banks (85.0%), poor electricity supply (77.5%), inadequate extension service support (70.0%), and fuel scarcity (68.7%) were major constraints to fish processing in the study area. Results of chi-square analysis showed that there was a significant relationship between personal characteristics (χ2 = 36.83, df = 9), processing methods (χ2 = 15.88, df = 3) and income generated at p < 0.05 level of significance. It can be concluded that significant relationship existed between processing methods and income generated. The study, therefore, recommends that modern processing equipment should be made available to the respondents at a subsidized price by the agro-allied companies.

Keywords: correlates, income, fish processors, women, small-scale

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6139 Projects and Limits of Memory Engineering: A Case of Lithuanian Partisan War

Authors: Mingaile Jurkute, Vilnius University

Abstract:

The memory of the Lithuanian partisan war (1944-1953) underwent extremely dramatic transformations. During this war, the image of the resistance and a partisan was one of the key elements of Lithuanian identity. Its importance is evidenced by the extremely large legacy of songs about partisans, no other topic has collected so much folklore in Lithuania. In the Soviet years, this resistance was practically forced to be forgotten. Terror and Soviet laws have forced people to stop talking about the events, even in the family circle. In addition, the Soviets created their own propaganda story, reinterpreting the Lithuanian partisan war, presenting partisans as bandits who brutally tortured and murdered locals. But even in the Soviet years, the memory could neither be completely suppressed, nor completely transformed into wishful shape. The analysis of fiction and cinema shows that the traumatic memory of real events rushed to the surface, thus transforming the very propagandistic narrative. After the restoration of the Republic of Lithuania in 1990, the Lithuanian partisan war was gradually returned to the central place of Lithuanian history. After 2014 the nationalist heroic narrative about Lithuanian partisans became the central narrative of modern Lithuanian history. Nevertheless, interviews I conducted in Lithuanian villages reveal that the memory of local communities and families preserves quite different experiences that do not fit into neither the Soviet narrative nor the heroic one. Such experiences include, for example, partisan violence against local families. This paper is about the efforts of two political ideologies (the Soviet and the Lithuanian patriotic) to use the history of the Lithuanian partisans for their own needs, and the attempts of small communities (mostly families) to resist these efforts. The research reveals that family memory, even when opposed to aggressive state memory policies, can preserve counter-narratives by exploiting unexpected objects beyond the control of the state, such as nature and wildlife. Basically, the paper analyses the limits of the instrumentalization of memory, even by extremely aggressive political regimes.

Keywords: collective memory, post-memory, violence, military conflict, family memory

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6138 The Effect of Common Daily Schedule on the Human Circadian Rhythms during the Polar Day on Svalbard: Field Study

Authors: Kamila Weissova, Jitka Skrabalova, Katerina Skalova, Jana Koprivova, Zdenka Bendova

Abstract:

Any Arctic visitor has to deal with extreme conditions, including constant light during the summer season or constant darkness during winter time. Light/dark cycle is the most powerful synchronizing signal for biological clock and the absence of daily dark period during the polar day can significantly alter the functional state of the internal clock. However, the inner clock can be synchronized by other zeitgebers such as physical activity, food intake or social interactions. Here, we investigated the effect of polar day on circadian clock of 10 researchers attending the polar base station in the Svalbard region during July. The data obtained on Svalbard were compared with the data obtained before the researchers left for the expedition (in the Czech Republic). To determine the state of circadian clock we used wrist actigraphy followed by sleep diaries, saliva, and buccal mucosa samples, both collected every 4 hours during 24h-interval to detect melatonin by radioimmunoassay and clock gene (PER1, BMAL1, NR1D1, DBP) mRNA levels by RT-qPCR. The clock gene expression was analyzed using cosinor analysis. From our results, it is apparent that the constant sunlight delayed melatonin onset and postponed the physical activity in the same order. Nevertheless, the clock gene expression displayed higher amplitude on Svalbard compared to the amplitude detected in the Czech Republic. These results have suggested that the common daily schedule at the Svalbard expedition can strengthen circadian rhythm in the environment that is lacking light/dark cycle. In conclusion, the constant sunlight delays melatonin onset, but it still maintains its rhythmic secretion. The effect of constant sunlight on circadian clock can be minimalized by common daily scheduled activity.

Keywords: actighraph, clock genes, human, melatonin, polar day

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6137 Single-Walled Carbon Nanotube Synthesis by Chemical Vapor Deposition Using Platinum-Group Metal Catalysts

Authors: T. Maruyama, T. Saida, S. Naritsuka, S. Iijima

Abstract:

Single-walled carbon nanotubes (SWCNTs) are generally synthesized by chemical vapor deposition (CVD) using Fe, Co, and Ni as catalysts. However, due to the Ostwald ripening of metal catalysts, the diameter distribution of the grown SWCNTs is considerably wide (>2 nm), which is not suitable for electronics applications. In addition, reduction in the growth temperature is desirable for fabricating SWCNT devices compatible with the LSI process. Herein, we performed SWCNT growth by alcohol catalytic CVD using platinum-group metal catalysts (Pt, Rh, and Pd) because these metals have high melting points, and the reduction in the Ostwald ripening of catalyst particles is expected. Our results revealed that web-like SWCNTs were obtained from Pt and Rh catalysts at growth temperature between 500 °C and 600 °C by optimizing the ethanol pressure. The SWCNT yield from Pd catalysts was considerably low. By decreasing the growth temperature, the diameter and chirality distribution of SWCNTs from Pt and Rh catalysts became small and narrow. In particular, the diameters of most SWCNTs grown using Pt catalysts were below 1 nm and their diameter distribution was considerably narrow. On the contrary, SWCNTs can grow from Rh catalysts even at 300 °C by optimizing the growth condition, which is the lowest temperature recorded for SWCNT growth. Our results demonstrated that platinum-group metals are useful for the growth of small-diameter SWCNTs and facilitate low-temperature growth.

Keywords: carbon nanotube, chemical vapor deposition, catalyst, platinum, rhodium, palladium

Procedia PDF Downloads 333