Search results for: Computational techniques
12 Effect of the Polymer Modification on the Cytocompatibility of Human and Rat Cells
Authors: N. Slepickova Kasalkova, P. Slepicka, L. Bacakova, V. Svorcik
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Tissue engineering includes combination of materials and techniques used for the improvement, repair or replacement of the tissue. Scaffolds, permanent or temporally material, are used as support for the creation of the "new cell structures". For this important component (scaffold), a variety of materials can be used. The advantage of some polymeric materials is their cytocompatibility and possibility of biodegradation. Poly(L-lactic acid) (PLLA) is a biodegradable, semi-crystalline thermoplastic polymer. PLLA can be fully degraded into H2O and CO2. In this experiment, the effect of the surface modification of biodegradable polymer (performed by plasma treatment) on the various cell types was studied. The surface parameters and changes of the physicochemical properties of modified PLLA substrates were studied by different methods. Surface wettability was determined by goniometry, surface morphology and roughness study were performed with atomic force microscopy and chemical composition was determined using photoelectron spectroscopy. The physicochemical properties were studied in relation to cytocompatibility of human osteoblast (MG 63 cells), rat vascular smooth muscle cells (VSMC), and human stem cells (ASC) of the adipose tissue in vitro. A fluorescence microscopy was chosen to study and compare cell-material interaction. Important parameters of the cytocompatibility like adhesion, proliferation, viability, shape, spreading of the cells were evaluated. It was found that the modification leads to the change of the surface wettability depending on the time of modification. Short time of exposition (10-120 s) can reduce the wettability of the aged samples, exposition longer than 150 s causes to increase of contact angle of the aged PLLA. The surface morphology is significantly influenced by duration of modification, too. The plasma treatment involves the formation of the crystallites, whose number increases with increasing time of modification. On the basis of physicochemical properties evaluation, the cells were cultivated on the selected samples. Cell-material interactions are strongly affected by material chemical structure and surface morphology. It was proved that the plasma treatment of PLLA has a positive effect on the adhesion, spreading, homogeneity of distribution and viability of all cultivated cells. This effect was even more apparent for the VSMCs and ASCs which homogeneously covered almost the whole surface of the substrate after 7 days of cultivation. The viability of these cells was high (more than 98% for VSMCs, 89-96% for ASCs). This experiment is one part of the basic research, which aims to easily create scaffolds for tissue engineering with subsequent use of stem cells and their subsequent "reorientation" towards the bone cells or smooth muscle cells.
Keywords: Poly(L-lactic acid), plasma treatment, surface characterization, cytocompatibility, human osteoblasts, rat vascular smooth muscle cells, human stem cells.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 98611 Effect of Different Contaminants on Mineral Insulating Oil Characteristics
Authors: H. M. Wilhelm, P. O. Fernandes, L. P. Dill, C. Steffens, K. G. Moscon, S. M. Peres, V. Bender, T. Marchesan, J. B. Ferreira Neto
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Deterioration of insulating oil is a natural process that occurs during transformers operation. However, this process can be accelerated by some factors, such as oxygen, high temperatures, metals and, moisture, which rapidly reduce oil insulating capacity and favor transformer faults. Parts of building materials of a transformer can be degraded and yield soluble compounds and insoluble particles that shorten the equipment life. Physicochemical tests, dissolved gas analysis (including propane, propylene and, butane), volatile and furanic compounds determination, besides quantitative and morphological analyses of particulate are proposed in this study in order to correlate transformers building materials degradation with insulating oil characteristics. The present investigation involves tests of medium temperature overheating simulation by means of an electric resistance wrapped with the following materials immersed in mineral insulating oil: test I) copper, tin, lead and, paper (heated at 350-400 °C for 8 h); test II) only copper (at 250 °C for 11 h); and test III) only paper (at 250 °C for 8 h and at 350 °C for 8 h). A different experiment is the simulation of electric arc involving copper, using an electric welding machine at two distinct energy sets (low and high). Analysis results showed that dielectric loss was higher in the sample of test I, higher neutralization index and higher values of hydrogen and hydrocarbons, including propane and butane, were also observed. Test III oil presented higher particle count, in addition, ferrographic analysis revealed contamination with fibers and carbonized paper. However, these particles had little influence on the oil physicochemical parameters (dielectric loss and neutralization index) and on the gas production, which was very low. Test II oil showed high levels of methane, ethane, and propylene, indicating the effect of metal on oil degradation. CO2 and CO gases were formed in the highest concentration in test III, as expected. Regarding volatile compounds, in test I acetone, benzene and toluene were detected, which are oil oxidation products. Regarding test III, methanol was identified due to cellulose degradation, as expected. Electric arc simulation test showed the highest oil oxidation in presence of copper and at high temperature, since these samples had huge concentration of hydrogen, ethylene, and acetylene. Particle count was also very high, showing the highest release of copper in such conditions. When comparing high and low energy, the first presented more hydrogen, ethylene, and acetylene. This sample had more similar results to test I, pointing out that the generation of different particles can be the cause for faults such as electric arc. Ferrography showed more evident copper and exfoliation particles than in other samples. Therefore, in this study, by using different combined analytical techniques, it was possible to correlate insulating oil characteristics with possible contaminants, which can lead to transformers failure.
Keywords: Ferrography, gas analysis, insulating mineral oil, particle contamination, transformer failures.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 45610 Child Sexual Abuse Prevention: Evaluation of the Program “Sharing Mouth to Mouth: My Body, Nobody Can Touch It”
Authors: Faride Peña, Teresita Castillo, Concepción Campo
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Sexual violence, and particularly child sexual abuse, is a serious problem all over the world, México included. Given its importance, there are several preventive and care programs done by the government and the civil society all over the country but most of them are developed in urban areas even though these problems are especially serious in rural areas. Yucatán, a state in southern México, occupies one of the first places in child sexual abuse. Considering the above, the University Unit of Clinical Research and Victimological Attention (UNIVICT) of the Autonomous University of Yucatan, designed, implemented and is currently evaluating the program named “Sharing Mouth to Mouth: My Body, Nobody Can Touch It”, a program to prevent child sexual abuse in rural communities of Yucatán, México. Its aim was to develop skills for the detection of risk situations, providing protection strategies and mechanisms for prevention through culturally relevant psycho-educative strategies to increase personal resources in children, in collaboration with parents, teachers, police and municipal authorities. The diagnosis identified that a particularly vulnerable population were children between 4 and 10 years. The program run during 2015 in primary schools in the municipality whose inhabitants are mostly Mayan. The aim of this paper is to present its evaluation in terms of its effectiveness and efficiency. This evaluation included documental analysis of the work done in the field, psycho-educational and recreational activities with children, evaluation of knowledge by participating children and interviews with parents and teachers. The results show high efficiency in fulfilling the tasks and achieving primary objectives. The efficiency shows satisfactory results but also opportunity areas that can be resolved with minor adjustments to the program. The results also show the importance of including culturally relevant strategies and activities otherwise it minimizes possible achievements. Another highlight is the importance of participatory action research in preventive approaches to child sexual abuse since by becoming aware of the importance of the subject people participate more actively; in addition to design culturally appropriate strategies and measures so that the proposal may not be distant to the people. Discussion emphasizes the methodological implications of prevention programs (convenience of using participatory action research (PAR), importance of monitoring and mediation during implementation, developing detection skills tools in creative ways using psycho-educational interactive techniques and working assessment issued by the participants themselves). As well, it is important to consider the holistic character this type of program should have, in terms of incorporating social and culturally relevant characteristics, according to the community individuality and uniqueness, consider type of communication to be used and children’ language skills considering that there should be variations strongly linked to a specific cultural context.
Keywords: Child sexual abuse, evaluation, PAR, prevention.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12469 Empirical Study on Causes of Project Delays
Authors: Khan Farhan Rafat, Riaz Ahmed
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Renowned offshore organizations are drifting towards collaborative exertion to win and implement international projects for business gains. However, devoid of financial constraints, with the availability of skilled professionals, and despite improved project management practices through state-of-the-art tools and techniques, project delays have become a norm these days. This situation calls for exploring the factor(s) affecting the bonding between project management performance and project success. In the context of the well-known 3M’s of project management (that is, manpower, machinery, and materials), machinery and materials are dependent upon manpower. Because the body of knowledge inveterate on the influence of national culture on men, hence, the realization of the impact on the link between project management performance and project success need to be investigated in detail to arrive at the possible cause(s) of project delays. This research initiative was, therefore, undertaken to fill the research gap. The unit of analysis for the proposed research excretion was the individuals who had worked on skyscraper construction projects. In reverent studies, project management is best described using construction examples. It is due to this reason that the project oriented city of Dubai was chosen to reconnoiter on causes of project delays. A structured questionnaire survey was disseminated online with the courtesy of the Project Management Institute local chapter to carry out the cross-sectional study. The Construction Industry Institute, Austin, of the United States of America along with 23 high-rise builders in Dubai were also contacted by email requesting for their contribution to the study and providing them with the online link to the survey questionnaire. The reliability of the instrument was warranted using Cronbach’s alpha coefficient of 0.70. The appropriateness of sampling adequacy and homogeneity in variance was ensured by keeping Kaiser–Meyer–Olkin (KMO) and Bartlett’s test of sphericity in the range ≥ 0.60 and < 0.05, respectively. Factor analysis was used to verify construct validity. During exploratory factor analysis, all items were loaded using a threshold of 0.4. Four hundred and seventeen respondents, including members from top management, project managers, and project staff, contributed to the study. The link between project management performance and project success was significant at 0.01 level (2-tailed), and 0.05 level (2-tailed) for Pearson’s correlation. Before initiating the moderator analysis test for linearity, multicollinearity, outliers, leverage points and influential cases, test for homoscedasticity and normality were carried out which are prerequisites for conducting moderator review. The moderator analysis, using a macro named PROCESS, was performed to verify the hypothesis that national culture has an influence on the said link. The empirical findings, when compared with Hofstede's results, showed high power distance as the cause of construction project delays in Dubai. The research outcome calls for the project sponsors and top management to reshape their project management strategy and allow for low power distance between management and project personnel for timely completion of projects.Keywords: Causes of construction project delays, construction industry, construction management, power distance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31208 Malaria Prone Zones of West Bengal: A Spatio-Temporal Scenario
Authors: Meghna Maiti, Utpal Roy
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In India, till today, malaria is considered to be one of the significant infectious diseases. Most of the cases regional geographical factors are the principal elements to let the places a unique identity. The incidence and intensity of infectious diseases are quite common and affect different places differently across the nation. The present study aims to identify spatial clusters of hot spots and cold spots of malaria incidence and their seasonal variation during the three periods of 2012-2014, 2015-2017 and 2018-20 in the state of West Bengal in India. As malaria is a vector-borne disease, numbers of positive test results are to be reported by the laboratories to the Department of Health, West Bengal (through the National Vector Borne Disease Control Programme). Data on block-wise monthly malaria positive cases are collected from Health Management Information System (HMIS), Ministry of Health and Family Welfare, Government of India. Moran’s I statistic is performed to assess the spatial autocorrelation of malaria incidence. The spatial statistical analysis mainly Local Indicators of Spatial Autocorrelation (LISA) cluster and Local Geary Cluster are applied to find the spatial clusters of hot spots and cold spots and seasonal variability of malaria incidence over the three periods. The result indicates that the spatial distribution of malaria is clustered during each of the three periods of 2012-2014, 2015-2017 and 2018-20. The analysis shows that in all the cases, high-high clusters are primarily concentrated in the western (Purulia, Paschim Medinipur districts), central (Maldah, Murshidabad districts) and the northern parts (Jalpaiguri, Kochbihar districts) and low-low clusters are found in the lower Gangetic plain (central-south) mainly and northern parts of West Bengal during the stipulated period. Apart from this seasonal variability inter-year variation is also visible. The results from different methods of this study indicate significant variation in the spatial distribution of malaria incidence in West Bengal and high incidence clusters are primarily persistently concentrated over the western part during 2012-2020 along with a strong seasonal pattern with a peak in rainy and autumn. By applying the different techniques in identifying the different degrees of incidence zones of malaria across West Bengal, some specific pockets or malaria hotspots are marked and identified where the incidence rates are quite harmonious over the different periods. From this analysis, it is clear that malaria is not a disease that is distributed uniformly across the state; some specific pockets are more prone to be affected in particular seasons of each year. Disease ecology and spatial patterns must be the factors in explaining the real factors for the higher incidence of this issue within those affected districts. The further study mainly by applying empirical approach is needed for discerning the strong relationship between communicable disease and other associated affecting factors.
Keywords: Malaria, infectious diseases, spatial statistics, spatial autocorrelation, LISA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5327 Effects of Pterocarpus mildbraedii Leaf Extract and Its Fractions on Cadmium and Lead Chloride-Induced Testicular Damage in Male Albino Rats
Authors: R. U. Hamzah, H. L. Muhammad, A. Sayyadi, M. B Busari, R. Garba, M. B. Umar, A. N Abubakar
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Lead (Pb) and Cadmium (Cd) are toxic, non-essential transition metals that pose many health risks for both humans and animals. They are environmental toxicants which contribute to testicular damage resulting to infertility problem among male populace worldwide. Chelating agents used for lead and cadmium toxicity are not readily available, toxic, expensive and unable to mop up most of the toxic metals accumulated in various organs. In this study, the effect of crude extract (CE), ethyl acetate fraction (EF) and acetone fraction (AF) of Pterocarpus mildbraedii leaf extract was assessed on cadmium-lead chloride induced testicular damaged in male albino Wistar rats. CE of the leaf was obtained by extracting in absolute methanol which was further subjected to solvent partitioning via vacuum liquid chromatographic (VLC) techniques using ethyl acetate, acetone and 70% methanol. A preliminary phytochemical screening and in vitro antioxidants guided activities on the CE and fractions were determined using standard methods. EF, AF and CE which exhibited significant in vitro activity were subjected to an in vivo study using Wistar rats. In vivo antioxidant markers, male reproductive hormones, testicular enzymes and DNA damage markers were analyzed on the rats’ testes supernatant. AF had the highest quantities of phenols (319.00 mg/g), flavonoids (8.87 mg/g) and tannins (8.87 mg/g) while methanol and EFs were richer in saponins (135.32 µg/g) and alkaloids (38.34 µg/g) respectively. A dose dependent 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP) and lipid peroxidation were observed in all the extract with high antioxidants power in CE and AF. Administration of lead-cadmium chloride solution significantly (p > 0.05) decreases the testicular superoxide dismutase (SOD) activity to 6.82 unit/mg protein, Catalase (CAT) activity to 8.07 of H2O2 consumed/unit/mg protein and Glutathione (GSH) concentration to 31.30 ug/mg protein. There was a concomitant increase in the level of Malondialdehyde (MDA) to a value of 23.70 mmol/mg protein. In addition, lead-cadmium chloride solution significantly (p > 0.05) increases the testicular marker enzymes (Alkaline phosphatase (119.57 u/L), lactate dehydrogenase (357.05 u/L), Acid phosphatase (98.65 u/L)) and DNA damage markers (conjugated dienes (93.39 nmol/mg protein), carbonyl protein (35.39 nmol/mg protein), DNA fragmentation percentage (32.12%)) with lowered testicular hormones (Testosterone (3.1 ng/mL), Follicle stimulating (0.35 IU/mL) and Luteinizing hormones (0.15 IU/mL)) of the animals in negative control group when compared with other treated groups. Treatment with Pterocarpus mildbraedii leaf extract reverts the observed changes with the best activities found in the CE and AFs in a dose dependent manner. Pterocarpus mildbraedii leaf extract ameliorated the lead/cadmium induced testicular damage in male albino rats. The restoration of the aforementioned parameters by some of the extract dosages were comparable to the standard drug with higher activities in the crude and AF. Therefore, Pterocarpus mildbraedii leaf extract can be explored further for the management of lead/cadmium induced toxicity.
Keywords: Cadmium, lead, Pterocarpus mildbraedii, testicular damage.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3846 Weaving Social Development: An Exploratory Study of Adapting Traditional Textiles Using Indigenous Organic Wool for the Modern Interior Textiles Market
Authors: Seema Singh, Puja Anand, Alok Bhasin
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The interior design profession aims to create aesthetically pleasing design solutions for human habitats but of late, growing awareness about depleting environmental resources, both tangible and intangible, and damages to the eco-system led to the quest for creating healthy and sustainable interior environments. The paper proposes adapting traditionally produced organic wool textiles for the mainstream interior design industry. This can create sustainable livelihoods whereby eco-friendly bridges can be built between Interior designers and consumers and pastoral communities. This study focuses on traditional textiles produced by two pastoral communities from India that use organic wool from indigenous sheep varieties. The Gaddi communities of Himachal Pradesh use wool from the Gaddi sheep breed to create Pattu (a multi-purpose textile). The Kurumas of Telangana weave a blanket called the Gongadi, using wool from the Black Deccani variety of sheep. These communities have traditionally reared indigenous sheep breeds for their wool and produce hand-spun and hand-woven textiles for their own consumption, using traditional processes that are chemical free. Based on data collected personally from field visits and documentation of traditional crafts of these pastoral communities, and using traditionally produced indigenous organic wool, the authors have developed innovative textile samples by including design interventions and exploring dyeing and weaving techniques. As part of the secondary research, the role of pastoralism in sustaining the eco-systems of Himachal Pradesh and Telangana was studied, and also the role of organic wool in creating healthy interior environments. The authors found that natural wool from indigenous sheep breeds can be used to create interior textiles that have the potential to be marketed to an urban audience, and this will help create earnings for pastoral communities. Literature studies have shown that organic & sustainable wool can reduce indoor pollution & toxicity levels in interiors and further help in creating healthier interior environments. Revival of indigenous breeds of sheep can further help in rejuvenating dying crafts, and promotion of these indigenous textiles can help in sustaining traditional eco-systems and the pastoral communities whose way of life is endangered today. Based on research and findings, the authors propose that adapting traditional textiles can have potential for application in Interiors, creating eco-friendly spaces. Interior textiles produced through such sustainable processes can help reduce indoor pollution, give livelihood opportunities to traditional economies, and leave almost zero carbon foot-print while being in sync with available natural resources, hence ultimately benefiting the society. The win-win situation for all the stakeholders in this eco-friendly model makes it pertinent to re-think how we design lifestyle textiles for interiors. This study illustrates a specific example from the two pastoral communities and can be used as a model that can work equally well in any community, regardless of geography.Keywords: Design Intervention, Eco-Friendly, Healthy Interiors, Indigenous, Organic Wool, Pastoralism, Sustainability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13925 Extremism among College and High School Students in Moscow: Diagnostics Features
Authors: Puzanova Zhanna Vasilyevna, Larina Tatiana Igorevna, Tertyshnikova Anastasia Gennadyevna
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In this day and age, extremism in various forms of its manifestation is a real threat to the world community, the national security of a state and its territorial integrity, as well as to the constitutional rights and freedoms of citizens. Extremism, as it is known, in general terms described as a commitment to extreme views and actions, radically denying the existing social norms and rules. Supporters of extremism in the ideological and political struggles often adopt methods and means of psychological warfare, appeal not to reason and logical arguments, but to emotions and instincts of the people, to prejudices, biases, and a variety of mythological designs. They are dissatisfied with the established order and aim at increasing this dissatisfaction among the masses. Youth extremism holds a specific place among the existing forms and types of extremism. In this context in 2015, we conducted a survey among Moscow college and high school students. The aim of this study was to determine how great or small is the difference in understanding and attitudes towards extremism manifestations, inclination and readiness to take part in extremist activities and what causes this predisposition, if it exists. We performed multivariate analysis and found the Russian college and high school students' opinion about the extremism and terrorism situation in our country and also their cognition on these topics. Among other things, we showed, that the level of aggressiveness of young people were not above the average for the whole population. The survey was conducted using the questionnaire method. The sample included college and high school students in Moscow (642 and 382, respectively) by method of random selection. The questionnaire was developed by specialists of RUDN University Sociological Laboratory and included both original questions (projective questions, the technique of incomplete sentences), and the standard test Dayhoff S. to determine the level of internal aggressiveness. It is also used as an experiment, the technique of study option using of FACS and SPAFF to determine the psychotypes and determination of non-verbal manifestations of emotions. The study confirmed the hypothesis that in respondents’ opinion, the level of aggression is higher today than a few years ago. Differences were found in the understanding of and respect for such social phenomena as extremism, terrorism, and their danger and appeal for the two age groups of young people. Theory of psychotypes, SPAFF (specific affect cording system) and FACS (facial action cording system) are considered as additional techniques for the diagnosis of a tendency to extreme views. Thus, it is established that diagnostics of acceptance of extreme views among young people is possible thanks to simultaneous use of knowledge from the different fields of socio-humanistic sciences. The results of the research can be used in a comparative context with other countries and as a starting point for further research in the field, taking into account its extreme relevance.Keywords: Extremism, youth extremism, diagnostics of extremist manifestations, forecast of behavior, Sociological polls, theory of psychotypes, FACS, SPAFF.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18184 Generative Syntaxes: Macro-Heterophony and the Form of ‘Synchrony’
Authors: Luminiţa Duţică, Gheorghe Duţică
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One of the most powerful language innovation in the twentieth century music was the heterophony–hypostasis of the vertical syntax entered into the sphere of interest of many composers, such as George Enescu, Pierre Boulez, Mauricio Kagel, György Ligeti and others. The heterophonic syntax has a history of its growth, which means a succession of different concepts and writing techniques. The trajectory of settling this phenomenon does not necessarily take into account the chronology: there are highly complex primary stages and advanced stages of returning to the simple forms of writing. In folklore, the plurimelodic simultaneities are free or random and originate from the (unintentional) differences/‘deviations’ from the state of unison, through a variety of ornaments, melismas, imitations, elongations and abbreviations, all in a flexible rhythmic and non-periodic/immeasurable framework, proper to the parlando-rubato rhythmics. Within the general framework of the multivocal organization, the heterophonic syntax in elaborate (academic) version has imposed itself relatively late compared with polyphony and homophony. Of course, the explanation is simple, if we consider the causal relationship between the sound vocabulary elements – in this case, the modalism – and the typologies of vertical organization appropriate for it. Therefore, adding up the ‘classic’ pathway of the writing typologies (monody – polyphony – homophony), heterophony - applied equally to the structures of modal, serial or synthesis vocabulary – reclaims necessarily an own macrotemporal form, in the sense of the analogies enshrined by the evolution of the musical styles and languages: polyphony→fugue, homophony→sonata. Concerned about the prospect of edifying a new musical ontology, the composer Ştefan Niculescu experienced – along with the mathematical organization of heterophony according to his own original methods – the possibility of extrapolation of this phenomenon in macrostructural plan, reaching this way to the unique form of ‘synchrony’. Founded on coincidentia oppositorum principle (involving the ‘one-multiple’ binom), the sound architecture imagined by Ştefan Niculescu consists in one (temporal) model / algorithm of articulation of two sound states: 1. monovocality state (principle of identity) and 2. multivocality state (principle of difference). In this context, the heterophony becomes an (auto)generative mechanism, with macrotemporal amplitude, strategy that will be grown by the composer, practically throughout his creation (see the works: Ison I, Ison II, Unisonos I, Unisonos II, Duplum, Triplum, Psalmus, Héterophonies pour Montreux (Homages to Enescu and Bartók etc.). For the present demonstration, we selected one of the most edifying works of Ştefan Niculescu – Simphony II, Opus dacicum – where the form of (heterophony-)synchrony acquires monumental-symphonic features, representing an emblematic case for the complexity level achieved by this type of vertical syntax in the twentieth century music.
Keywords: Heterophony, modalism, serialism, synchrony, syntax.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7293 Assessment of Occupational Exposure and Individual Radio-Sensitivity in People Subjected to Ionizing Radiation
Authors: Oksana G. Cherednichenko, Anastasia L. Pilyugina, Sergey N.Lukashenko, Elena G. Gubitskaya
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The estimation of accumulated radiation doses in people professionally exposed to ionizing radiation was performed using methods of biological (chromosomal aberrations frequency in lymphocytes) and physical (radionuclides analysis in urine, whole-body radiation meter, individual thermoluminescent dosimeters) dosimetry. A group of 84 "A" category employees after their work in the territory of former Semipalatinsk test site (Kazakhstan) was investigated. The dose rate in some funnels exceeds 40 μSv/h. After radionuclides determination in urine using radiochemical and WBC methods, it was shown that the total effective dose of personnel internal exposure did not exceed 0.2 mSv/year, while an acceptable dose limit for staff is 20 mSv/year. The range of external radiation doses measured with individual thermo-luminescent dosimeters was 0.3-1.406 µSv. The cytogenetic examination showed that chromosomal aberrations frequency in staff was 4.27±0.22%, which is significantly higher than at the people from non-polluting settlement Tausugur (0.87±0.1%) (р ≤ 0.01) and citizens of Almaty (1.6±0.12%) (р≤ 0.01). Chromosomal type aberrations accounted for 2.32±0.16%, 0.27±0.06% of which were dicentrics and centric rings. The cytogenetic analysis of different types group radiosensitivity among «professionals» (age, sex, ethnic group, epidemiological data) revealed no significant differences between the compared values. Using various techniques by frequency of dicentrics and centric rings, the average cumulative radiation dose for group was calculated, and that was 0.084-0.143 Gy. To perform comparative individual dosimetry using physical and biological methods of dose assessment, calibration curves (including own ones) and regression equations based on general frequency of chromosomal aberrations obtained after irradiation of blood samples by gamma-radiation with the dose rate of 0,1 Gy/min were used. Herewith, on the assumption of individual variation of chromosomal aberrations frequency (1–10%), the accumulated dose of radiation varied 0-0.3 Gy. The main problem in the interpretation of individual dosimetry results is reduced to different reaction of the objects to irradiation - radiosensitivity, which dictates the need of quantitative definition of this individual reaction and its consideration in the calculation of the received radiation dose. The entire examined contingent was assigned to a group based on the received dose and detected cytogenetic aberrations. Radiosensitive individuals, at the lowest received dose in a year, showed the highest frequency of chromosomal aberrations (5.72%). In opposite, radioresistant individuals showed the lowest frequency of chromosomal aberrations (2.8%). The cohort correlation according to the criterion of radio-sensitivity in our research was distributed as follows: radio-sensitive (26.2%) — medium radio-sensitivity (57.1%), radioresistant (16.7%). Herewith, the dispersion for radioresistant individuals is 2.3; for the group with medium radio-sensitivity — 3.3; and for radio-sensitive group — 9. These data indicate the highest variation of characteristic (reactions to radiation effect) in the group of radio-sensitive individuals. People with medium radio-sensitivity show significant long-term correlation (0.66; n=48, β ≥ 0.999) between the values of doses defined according to the results of cytogenetic analysis and dose of external radiation obtained with the help of thermoluminescent dosimeters. Mathematical models based on the type of violation of the radiation dose according to the professionals radiosensitivity level were offered.
Keywords: Biodosimetry, chromosomal aberrations, ionizing radiation, radiosensitivity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9382 The Influence of Fashion Bloggers on the Pre-Purchase Decision for Online Fashion Products among Generation Y Female Malaysian Consumers
Authors: Mohd Zaimmudin Mohd Zain, Patsy Perry, Lee Quinn
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This study explores how fashion consumers are influenced by fashion bloggers towards pre-purchase decision for online fashion products in a non-Western context. Malaysians rank among the world’s most avid online shoppers, with apparel the third most popular purchase category. However, extant research on fashion blogging focuses on the developed Western market context. Numerous international fashion retailers have entered the Malaysian market from luxury to fast fashion segments of the market; however Malaysian fashion consumers must balance religious and social norms for modesty with their dress style and adoption of fashion trends. Consumers increasingly mix and match Islamic and Western elements of dress to create new styles enabling them to follow Western fashion trends whilst paying respect to social and religious norms. Social media have revolutionised the way that consumers can search for and find information about fashion products. For online fashion brands with no physical presence, social media provide a means of discovery for consumers. By allowing the creation and exchange of user-generated content (UGC) online, they provide a public forum that gives individual consumers their own voices, as well as access to product information that facilitates their purchase decisions. Social media empower consumers and brands have important roles in facilitating conversations among consumers and themselves, to help consumers connect with them and one another. Fashion blogs have become an important fashion information sources. By sharing their personal style and inspiring their followers with what they wear on popular social media platforms such as Instagram, fashion bloggers have become fashion opinion leaders. By creating UGC to spread useful information to their followers, they influence the pre-purchase decision. Hence, successful Western fashion bloggers such as Chiara Ferragni may earn millions of US dollars every year, and some have created their own fashion ranges and beauty products, become judges in fashion reality shows, won awards, and collaborated with high street and luxury brands. As fashion blogging has become more established worldwide, increasing numbers of fashion bloggers have emerged from non-Western backgrounds to promote Islamic fashion styles, such as Hassanah El-Yacoubi and Dian Pelangi. This study adopts a qualitative approach using netnographic content analysis of consumer comments on two famous Malaysian fashion bloggers’ Instagram accounts during January-March 2016 and qualitative interviews with 16 Malaysian Generation Y fashion consumers during September-October 2016. Netnography adapts ethnographic techniques to the study of online communities or computer-mediated communications. Template analysis of the data involved coding comments according to the theoretical framework, which was developed from the literature review. Initial data analysis shows the strong influence of Malaysian fashion bloggers on their followers in terms of lifestyle and morals as well as fashion style. Followers were guided towards the mix and match trend of dress with Western and Islamic elements, for example, showing how vivid colours or accessories could be worked into an outfit whilst still respecting social and religious norms. The blogger’s Instagram account is a form of online community where followers can communicate and gain guidance and support from other followers, as well as from the blogger.Keywords: Fashion bloggers, Malaysia, qualitative, social media.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24811 Leading, Teaching and Learning “in the Middle”: Experiences, Beliefs, and Values of Instructional Leaders, Teachers, and Students in Finland, Germany, and Canada
Authors: Brandy Yee, Dianne Yee
Abstract:
Through the exploration of the lived experiences, beliefs and values of instructional leaders, teachers and students in Finland, Germany and Canada, we investigated the factors which contribute to developmentally responsive, intellectually engaging middle-level learning environments for early adolescents. Student-centred leadership dimensions, effective instructional practices and student agency were examined through the lens of current policy and research on middle-level learning environments emerging from the Canadian province of Manitoba. Consideration of these three research perspectives in the context of early adolescent learning, placed against an international backdrop, provided a previously undocumented perspective on leading, teaching and learning in the middle years. Aligning with a social constructivist, qualitative research paradigm, the study incorporated collective case study methodology, along with constructivist grounded theory methods of data analysis. Data were collected through semi-structured individual and focus group interviews and document review, as well as direct and participant observation. Three case study narratives were developed to share the rich stories of study participants, who had been selected using maximum variation and intensity sampling techniques. Interview transcript data were coded using processes from constructivist grounded theory. A cross-case analysis yielded a conceptual framework highlighting key factors that were found to be significant in the establishment of developmentally responsive, intellectually engaging middle-level learning environments. Seven core categories emerged from the cross-case analysis as common to all three countries. Within the visual conceptual framework (which depicts the interconnected nature of leading, teaching and learning in middle-level learning environments), these seven core categories were grouped into Essential Factors (student agency, voice and choice), Contextual Factors (instructional practices; school culture; engaging families and the community), Synergistic Factors (instructional leadership) and Cornerstone Factors (education as a fundamental cultural value; preservice, in-service and ongoing teacher development). In addition, sub-factors emerged from recurring codes in the data and identified specific characteristics and actions found in developmentally responsive, intellectually engaging middle-level learning environments. Although this study focused on 12 schools in Finland, Germany and Canada, it informs the practice of educators working with early adolescent learners in middle-level learning environments internationally. The authentic voices of early adolescent learners are the most important resource educators have to gauge if they are creating effective learning environments for their students. Ongoing professional dialogue and learning is essential to ensure teachers are supported in their work and develop the pedagogical practices needed to meet the needs of early adolescent learners. It is critical to balance consistency, coherence and dependability in the school environment with the necessary flexibility in order to support the unique learning needs of early adolescents. Educators must intentionally create a school culture that unites teachers, students and their families in support of a common purpose, as well as nurture positive relationships between the school and its community. A large, urban school district in Canada has implemented a school cohort-based model to begin to bring developmentally responsive, intellectually engaging middle-level learning environments to scale.
Keywords: Developmentally responsive learning environments, early adolescents, middle-level learning, middle years, instructional leadership, instructional practices, intellectually engaging learning environments, leadership dimensions, student agency.
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