Search results for: climate change.

Authors: A. Sadowska, R. Polaniak, P. Boczarski, E. Grochowska-Niedworok

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Working in a shopping center 12 hours a day as a shop assistant is a very demanding and stressful job, which is still underestimated. Proper eating habits, including recommended fruits, vegetables, products rich in fiber, omega-3 fatty acids, and proper hydration, can contribute to improvement in health and make shop assistants more resistant to stress. The aim of this study was to analyze the eating habits of shop assistants working in shopping centers 12 hours a day. Participant 101 sellers from Poland filled out authorial surveys. Nearly 50% of participants consumed the recommended number of 4 to 5 meals per day. There was a slight dependence between the number of meals consumed per day and the time that employers allowed for employee mealtimes. Respondents declared that they engaged in snacking, and they generally chose fruit, chocolates, and other sweets. Survey results indicated a low liquid intake, which was about 1,05 liters daily. Mineral water was chosen most often (63%) by participants. Participant fish consumption was very low in comparison with the norms, which can pose a risk of developing omega-3 fatty acids deficiency. Shop assistants stated that a change in their eating habits was necessary. Study findings suggest a moderate dependence between being on a diet and counting calories and macronutrients contained in meals. The number of meals eaten per day is correlated with the number of meals eaten at the worksite. The percentage of snacking by shop assistants was so high that it suggested a need for more nutrition education. The topic of eating habits among shop assistants should be examined using a larger group of participants. It is necessary to note a connection between nutrition and health problems.

Keywords: eating habits, work during 12 hours a day, shopping center, nutrition

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Authors: Getnet Gedefaw, Fentanesh Endalew, Bitewush Azmeraw, Bethelhem Walelign, Eyob Shitie

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Introduction: The issue of menstrual hygiene is often overlooked and has not been sufficiently addressed in the fields of reproductive health in low and middle-income countries. Inadequate menstrual hygiene practices can increase the risk of various infectious and chronic obstetric and gynaecological complications for girls and adolescents. Hence, this study seeks to investigate the knowledge, attitudes, and practices related to menstrual hygiene, along with the factors influencing them, among high school students. Methods: A facility based cross-sectional study was conducted involving a total of 423 study subjects. A systematic random sampling technique was utilized. Data was entered and analyzed through Epi data 3.1 and SPSS 22, respectively. Both univariable and multivariable logistic regression models were employed. A p-value of less than 0.05 was considered statistically significant. Results: This study revealed that 365(89.2%), 200(48.9%) and 196(47.9%) of the study participants have good knowledge, good practice, and good attitudes about menstrual hygiene, respectively. Being higher grade students (grade 10) [AOR=3.96, 95% CI =2.0-7.8] and having good practice of menstrual hygiene (AOR=2.52, 95% CI= 1.26-5) had a positive association with menstrual hygiene knowledge. Whereas maternal education level (AOR=1.86, 95% CI=1.18-2.9) and being a grade 10 student (AOR=2.3, 95% CI=1.48-3.56) were associated factors for practising menstrual hygiene. Additionally, being higher grade students (AOR=1.9, 95% CI=1.2-2.8), age ≥18 years (AOR=1.67, 95% CI=1.09-2.55) were statistically and positively associated with the attitude of menstrual hygiene. Conclusion: The study findings indicated that the knowledge of the study participants regarding menstrual hygiene was high, while their attitudes and practices towards menstrual hygiene were low. It is suggested that raising awareness among reproductive health groups and educating their families and parents could potentially lead to a positive change in their poor practices and attitudes towards menstrual hygiene.

Keywords: menstrual hygiene, menstruation, students, reproductive health

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Authors: Pearl K. Atuhaire, Sylvia Kaye

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While the need for equal access to civil, political as well as economic, social and cultural rights is clear under the international law, the adoption of the Convention on the Elimination of all forms of Discrimination against women in 1979 made this even clearer. Despite this positive progress, the abuse of refugee women's rights is one of the basic underlying root causes of their marginalisation and violence in their countries of asylum. This paper presents a critical review on the development of refugee women's rights at the international levels and national levels. It provides an array of scholarly literature on this issue and examines the measures taken by the international community to curb the problem of violence against women in their various provisions through the instruments set. It is cognizant of the fact that even if conflict affects both refugee women and men, the effects on women refugees are deep-reaching, due to the cultural strongholds they face. An important aspect of this paper is that it is conceptualised against the fact that refugee women face the problem of sexual and gender based first as refugees and second as women, yet, their rights are stumbled upon. Often times they have been rendered "worthless victims" who are only in need of humanitarian assistance than active participants committed to change their plight through their participation in political, economic and social participation in their societies. Scholars have taken notice of the fact that women's rights in refugee settings have been marginalized and call for a need to incorporate their perspectives in the planning and management of refugee settings in which they live. Underpinning this discussion is feminism theory which gives a clear understanding of the root cause of refugee women's problems. Finally, this paper suggests that these policies should be translated into action at local, national international and regional levels to ensure sustainable peace.

Keywords: feminism theory, human rights, refugee women, sexual and gender based violence

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Authors: Md. Zahirul Islam, Chad A. Ulven

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Fiber-reinforced polymer matrix composites have a wide range of applications in the sectors of automotive, aerospace, sports utilities, among others, due to their high specific strength, stiffness as well as reduced weight. In addition to those favorable properties, composites composed of natural fibers and bio-based resins (i.e., biocomposites) have eco-friendliness and biodegradability. However, the applications of biocomposites are limited due to the lack of knowledge about their long-term reliability under fluctuating loads. In order to explore the long-term reliability of flax fiber reinforced composites under fluctuating loads through high cycle fatigue strength (HCFS), fatigue test were conducted on unidirectional flax fiber reinforced thermoset composites at different percentage loads of ultimate tensile strength (UTS) with a loading frequency of 5 Hz. Change of temperature of the sample during cyclic loading was captured using an IR camera. Initially, the temperature increased rapidly, but after a certain time, it stabilized. A mathematical model was developed to predict the fatigue life from the data of stabilized temperature. Stabilized temperature and dissipated energy per cycle were compared with applied stress. Both showed bilinear behavior and the intersection of those curves were used to determine HCFS. HCFS for unidirectional flax fiber reinforced composites is around 45% of UTS for a loading frequency of 5Hz. Unlike fatigue life, stabilized temperature and dissipated energy-based models are convenient to define HCFS as they have little variation from sample to sample.

Keywords: energy method, fatigue, flax fiber reinforced composite, HCFS, thermographic approach

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Authors: Andres Mejia-Ortiz, Catalina Lozada, German R. Santos, Rafael Angulo-Jaramillo, Bernardo Caicedo

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The interaction between atmospheric variables and soil properties is a determining factor when evaluating the flow of water through the soil. This interaction situation directly determines the behavior of the soil and greatly influences the changes that occur in it. The atmospheric variations such as changes in the relative humidity, air temperature, wind velocity and precipitation, are the external variables that reflect a greater incidence in the changes that are generated in the subsoil, as a consequence of the water flow in descending and ascending conditions. These environmental variations have a major importance in the study of the soil because the conditions of humidity and temperature in the soil surface depend on them. In addition, these variations control the thickness of the unsaturated zone and the position of the water table with respect to the surface. However, understanding the relationship between the atmosphere and the soil is a somewhat complex aspect. This is mainly due to the difficulty involved in estimating the changes that occur in the soil from climate changes; since this is a coupled process where act processes of mass transfer and heat. In this research, an experimental field was implemented to study in-situ the interaction between the atmosphere and the soft soils of the city of Bogota, Colombia. The soil under study consists of a 60 cm layer composed of two silts of similar characteristics at the surface and a deep soft clay deposit located under the silky material. It should be noted that the vegetal layer and organic matter were removed to avoid the evapotranspiration phenomenon. Instrumentation was carried on in situ through a field disposal of many measuring devices such as soil moisture sensors, thermocouples, relative humidity sensors, wind velocity sensor, among others; which allow registering the variations of both the atmospheric variables and the properties of the soil. With the information collected through field monitoring, the water balances were made using the Hydrus-1D software to determine the flow conditions that developed in the soil during the study. Also, the moisture profile for different periods and time intervals was determined by the balance supplied by Hydrus 1D; this profile was validated by experimental measurements. As a boundary condition, the actual evaporation rate was included using the semi-empirical equations proposed by different authors. In this study, it was obtained for the rainy periods a descending flow that was governed by the infiltration capacity of the soil. On the other hand, during dry periods. An increase in the actual evaporation of the soil induces an upward flow of water, increasing suction due to the decrease in moisture content. Also, cracks were developed accelerating the evaporation process. This work concerns to the study of soil-atmosphere interaction through the experimental field and it is a very useful tool since it allows considering all the factors and parameters of the soil in its natural state and real values of the different environmental conditions.

Keywords: field monitoring, soil-atmosphere, soft soils, soil-water balance

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Authors: Rostam Abdi, Ahmad Abdi, Zahra Vahedi Langrodi

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The aim of this study is to investigate four-week resistance exercise and milk supplement on NT-proBNP and plasma troponin I of male students. Concerning the methodology of the study, 21 senior high school students of Ardebil city were selected. The selected subjects were randomly shared in three groups of control, exercise- water and exercise- milk. The exercise program includes resistance exercise for a big muscle group. The subjects of control group rested during the study and did not participate in any training. The subjects of exercise- water experimental group immediately received 400 cc water after exercise and exercise- milk group immediately received 400 cc low fat milk. Control-water groups consumed the same amount of water. 48 hours before and after the last exercise session, the blood sample of the subjects were taken for measuring the variables. NT-proBNP and Troponin I concentrations were measured by ELISA. For data analysis, one-way variance analysis test, correlated t-test and Bonferroni post hoc test were used. The significant difference of p ≤ 0.05 was accepted. Resistance training along with milk consumption leads to increase of plasma NT-proBNP, however; this increase has not reached the significant level. Furthermore, meaningful increase was observed in plasma NT–proBNP in exercise group between pretest and posttest values. Furthermore, no meaningful difference was observed between groups in terms of Troponin I after milk consumption. It seems that endurance exercises lead to change in the structure of heart muscle and is along with an increase of NT-proBNP. Furthermore, there is the possibility that milk consumption can lead to release of heart troponin I. The mechanism through which protein supplements have been put on heart troponin I is unknown and requires more research.

Keywords: resistance exercise, milk, NT-proBNP, Troponin I

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Authors: Tarek Hassan, Sanaa Abouras

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Some factors such as interaction of migration process, cultural identity have an impact in a way that may lead to cultural disinheritance. Even if migrants' culture would not be lost, it may be affected by the new society culture. Therefore, it is anticipated that migration of an ethnic group would impact the culture of that group. Nubians; an ethnic group originated in South Egypt, have experienced migration that took place in the sixties of the past century. Nubians were forced to leave their origin land and relocate to Kom Ombo; an Egyptian town to the north of Aswan. The effect of migration on national culture, social homogeneity or the interest of social contact influences the attitudes of natives towards migration. Hence, it is very important for societies to help migrants to adapt to the new culture and at the same time not to impede migrants' effort to maintain their own culture. This study aims to investigate the effect of internal migration on the culture of Egyptian Nubians in order to predict if Nubian can maintain their own culture after the migration. Research question: what is the cultural influence of Nubians' migration from Egyptian Nubia to their new destinations? The researchers' hypothesis: there is mutual influence between the two cultures of Nubians and non-Nubians in Egypt. Results supported researchers' hypothesis as they observed that the Nubians managed to reserve balance between the maintenance of their own culture and the adoption of some cultural features of the community of their new destination(s). Also, the study examined why Nubians adhere to their culture although they left their land forever. Questionnaire and interviews were used to collect data from 80 informants; 40 Nubians and 40 non-Nubians in Kom-Ombo and the two cities of Cairo and Alexandria. Results suggested that there is obvious mutual cultural impact between Nubians and non-Nubians. The findings of this study would trigger the researchers to conduct further research on minorities for the deeper understanding of the impact of/on the culture of minorities.

Keywords: culture change, culture influence, culture maintenance, minority migration

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Authors: Adhi Susilo

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This paper addresses the roles of distance education in the agricultural extension workers’ education. Agriculture plays an important role in both poverty reduction and economic growth. The technology of agriculture in the developing world should change continuously to keep pace with rising populations and rapidly changing social, economic, and environmental conditions. Therefore, agricultural extension workers should have several competencies in order to carry out their duties properly. One of the essential competencies that they must possess is the professional competency that is directly related to their duties in carrying out extension activities. Such competency can be acquired through studying at Universitas Terbuka (UT). With its distance learning system, agricultural extension workers can study at UT without leaving their duties. This paper presenting sociological analysis and lessons learnt from the specific context of Indonesia. Diversities in geographic, demographic, social cultural and economic conditions of the country provide specific challenges for its distance education practice and the process of social transformation to which distance education can contribute. Extension officers used distance education for personal benefits and increased professional productivity. An increase in awareness is important for the further adoption of distance learning for extension purposes. Organizations in both the public and private sector must work to increase knowledge of ICTs for the benefit of stakeholders. The use of ICTs can increase productivity for extensions officers and expand educational opportunities for learners. The use of distance education by extension to disseminate educational materials around the world is widespread. Increasing awareness and use of distance learning can lead to more productive relationships between extension officers and agricultural stakeholders.

Keywords: agricultural extension, demographic and geographic condition, distance education, ICTs

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Authors: A.Boularouk, F. Chouikh, M. Lamri, H. Moualkia, Y. Bouznit

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The principal aim of this study is to considerably reduce the resistivity of the SnO2 thin layers. In this order, we have doped tin oxide with aluminum and antimony incorporation with different atomic percentages (0 and 4%). All the pure and doped SnO2 films were grown by simple, flexible and cost-effective Automatic Spray Pyrolysis Method (ASPM) on glass substrates at a temperature of 350 °C. The microstructural, optical, morphological and electrical properties of the films have been studied. The XRD results demonstrate that all films have polycrystalline nature with a tetragonal rutile structure and exhibit the (200) preferential orientation. It has been observed that all the dopants are soluble in the SnO2 matrix without forming secondary phases. However, dopant introduction does not modify the film growth orientation. The crystallite size of the pure SnO2 film is about 36 nm. The films are highly transparent in the visible region with an average transmittance reaching up to 80% and it slightly reduces with increasing doping concentration (Al and Sb). The optical band gap value was evaluated between 3.60 eV and 3.75 eV as a function of doping. The SEM image reveals that all films are nanostructured, densely continuous, with good adhesion to the substrate. We note again that the surface morphology change with the type and concentration dopant. The minimum resistivity is 0.689*10-4, which is observed for SnO2 film doped 4% Al. This film shows better properties and is considered the best among all films. Finally, we concluded that the physical properties of the pure and doped SnO2 films grown on a glass substrate by ASPM strongly depend on the type and concentration dopant (Al and Sb) and have highly desirable optical and electrical properties and are promising materials for several applications.

Keywords: tin oxide, automatic spray, Al and Sb doped, transmittance, MEB, XRD and UV-VIS

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Authors: Eldar Mammadov, Konul Mammadova, Aytaj Ilyaszada

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Background: According to many studies, it is known that H. pylori transform into the coccoid form, which cannot be cultured and has poor metabolic activity.In this study, we succeeded in preserving the spiral shape of H.pylori for a long time by preparing a biphase transport medium with a hard bottom (Muller Hinton with 7% HRBC (horse red blood cells) agar 5ml) and liquid top part (BH (brain heart) broth + HS (horse serum)+7% HRBC+antibiotics (Vancomycin 5 mg, Trimethoprim lactate 25 mg, Polymyxin B 1250 I.U.)) in cell culture flasks with filter caps. For comparison, we also used a BH broth medium with 7% HRBC used for the transport of H.pylori. Methods: Rapid urease test positive 7 biopsy specimens were also inoculated into biphasic and BH broth medium with 7% HRBC, then put in CO2 Gaspak packages and sent to the laboratory. Then both mediums were kept in the thermostat at 37 °C for 1 day. After microscopic, PCR and urease test diagnosis, they were transferred to Columbia Agar with 7% HRBC. Incubated at 37°C for 5-7 days, cultures were examined for colony characteristics and bacterial morphology. E-test antimicrobial susceptibility test was performed. Results: There were 3 growths from biphasic transport medium passed to Columbia agar with 7% HRBC and only 1 growth from BH broth medium with 7% HRBC. It was also observed that after the first 3 days in BH broth medium with 7%, H.pylori passed into coccoid form and its biochemical activity weakened, while its spiral shape did not change for 2-3 weeks in the biphase transport medium. Conclusions: By using the biphase transport medium we have prepared; we can culture the bacterium by preventing H.pylori from spiraling into the coccoid form. In our opinion, this may result in the wide use of culture method for diagnosis of H.pylori, study of antibiotic susceptibility and molecular genetic analysis.

Keywords: clinical trial, H.pylori, coccoid form, transport medium

Procedia PDF Downloads 73

Authors: M. A. Mamun, M. I. Khan, M. H. Sarker, K. A. Khan, M. Shajahan

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The study was carried out to investigate on an innovative invention, Pathor Kuchi Leaf (PKL) cell, which is fueled with PKL sap of widely available plant called Bryophyllum pinnatum as an energy source for use in PKL battery to generate electricity. This battery, a primary source of electricity, has several order of magnitude longer shelf-lives than the traditional Galvanic cell battery, is still under investigation. In this regard, we have conducted some experiments using various instruments including Atomic Absorption Spectrophotometer (AAS), Ultra-Violet Visible spectrophotometer (UV-Vis), pH meter, Ampere-Volt-Ohm Meter (AVO Meter), etc. The AAS, UV-Vis, and pH-metric analysis data provided that the potential and current were produced as the Zn electrode itself acts as reductant while Cu2+ and H+ ions are behaving as the oxidant. The significant influence of secondary salt on current and potential leads to the dissociation of weak organic acids in PKL juice, and subsequent enrichment to the reactant ions by the secondary salt effects. However, the liquid junction potential was not as great as minimized with the opposite transference of organic acid anions and H+ ions as their dissimilar ionic mobilities. Moreover, the large value of the equilibrium constant (K) implies the big change in Gibbs free energy (∆G), the more electromotive force works in electron transfer during the forward electrochemical reaction which coincides with the fast reduction of the weight of zinc plate, revealed the additional electrical work in the presence of PKL sap. This easily fabricated high-performance PKL battery can show an excellent promise during the off-peak across the countryside.

Keywords: Atomic Absorption Spectrophotometer (AAS), Bryophylum Pinnatum Leaf (BPL), electricity, electrochemistry, organic acids

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Authors: Harish Bisht, Bahadur Singh Kotlia, Kireet Kumar

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In order to reconstruct past retreating rates, total area loss, volume change and shift in snout position were measured through multi-temporal satellite data from 1989 to 2016 and kinematic GPS survey from 2015 to 2016. The results obtained from satellite data indicate that in the last 27 years, Chaturangi glacier snout has retreated 1172.57 ± 38.3 m (average 45.07 ± 4.31 m/year) with a total area and volume loss of 0.626 ± 0.001 sq. Km and 0.139 Km³, respectively. The field measurements through differential global positioning system survey revealed that the annual retreating rate was 22.84 ± 0.05 m/year. The large variations in results derived from both the methods are probably because of higher difference in their accuracy. Snout monitoring of the Gangotri glacier during the ablation season (May to September) in the years 2005 and 2015 reveals that the retreating rate has been comparatively more declined than that shown by the earlier studies. The GPS dataset shows that the average recession rate is 10.26 ± 0.05 m/year. In order to determine the possible causes of decreased retreating rate, a relationship between debris thickness and melt rate was also established by using ablation stakes. The present study concludes that remote sensing method is suitable for large area and long term study, while kinematic GPS is more appropriate for the annual monitoring of retreating rate of glacier snout. The present study also emphasizes on mapping of all the tributary glaciers in order to assess the overall changes in the main glacier system and its health.

Keywords: Chaturangi glacier, Gangotri glacier, glacier snout, kinematic global positioning system, retreat rate

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Authors: Choo Hong Ang

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The most popular approach to save energy for large commercial buildings in Malaysia is to replace the existing chiller plant of high kW/ton to one of lower kW/ton. This approach, however, entails large capital outlay with a long payment period of up to 7 years. This paper shows that by using multiple approaches, other than replacing the existing chiller plant, an energy saving of up to 20 %, is possible. The main methodology adopted was to identify and then plugged all heat ingress paths into a building, including putting up glass structures to prevent mixing of internal air-conditioned air with the ambient environment, and replacing air curtains with glass doors. This methodology could save up to 10 % energy bill. Another methodology was to change fixed speed motors of air handling units (AHU) to variable speed drive (VSD) and changing escalators to motion-sensor type. Other methodologies included reducing heat load by blocking air supply to non-occupied parcels, rescheduling chiller plant operation, changing of fluorescent lights to LED lights, and conversion from tariff B to C1. A case example of Komtar, the tallest building in Penang, is given here. The total energy bill for Komtar was USD2,303,341 in 2016 but was reduced to USD 1,842,927.39 in 2018, a significant saving of USD460,413.86 or 20 %. In terms of kWh, there was a reduction from 18, 302,204.00 kWh in 2016 to 14,877,105.00 kWh in 2018, a reduction of 3,425,099.00 kWh or 18.71 %. These methodologies used were relatively low cost and the payback period was merely 24 months. With this achievement, the Komtar building was awarded champion of the Malaysian National Energy Award 2019 and second runner up of the Asean Energy Award. This experience shows that a strong commitment to energy saving is the key to effective energy saving.

Keywords: chiller plant, energy saving measures, heat ingress, large building

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Authors: Raviteja Chintala

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Water shortage in many areas of the world have predominantly increased the demand for efficient methods involved in the production of drinking water, So purification of water invoking cost effective and efficient methods is a challenging field of research. In this regard, Reverse osmosis membrane desalination of both seawater and inland brackish water is currently being deployed in various locations around the world. In the present work an attempt is made to integrate these existing technologies with novel method, Wherein carbon nanotubes at the lab scale are prepared which further replace activated carbon tubes being used traditionally. This has proven to enhance the efficiency of the water filter, Effectively neutralising most of the organic impurities. Furthermore, This ensures the reduction in TDS. Carbon nanotubes have wide range in scope of applications such as composite reinforcements, Field emitters, Sensors, Energy storage and energy conversion devices and catalysts support phases, Because of their unusual mechanical, Electrical, Thermal and structural properties. In particular, The large specific surface area, as well as the high chemical and thermal stability, Makes carbon nanotube an attractive adsorbent in waste water treatment. Carbon nanotubes are effective in eliminating these harmful media from water as an adsorbent. In this work, Candle soot method has been incorporated for the preparation of carbon nanotubes and mixed with activated charcoal in different compositions. The effect of composition change is monitored by using TDS measuring meter. As the composition of Nano carbon increases, The TDS of the water gradually decreases. In order to enhance the life time for carbon filter, Nano tubes are provided with larger surface area.

Keywords: TDS (Total Dissolved Solids), carbon nanotubes, water, candle soot

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Authors: Z. Dedovets, M. Rodionov

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The goal of the modern education system is to prepare students to be able to adapt to ever-changing life situations. They must be able to acquire required knowledge independently; apply such knowledge in practice to solve various problems by using modern technologies; think critically and creatively; competently use information; be communicative, work in a team; and develop their own moral values, intellect and cultural awareness. As a result, the status of education significantly increases; new requirements to its quality have been formed. In recent years, the competency-based approach in education has become of significant interest. This approach is a strengthening of applied and practical characteristics of a school education and leads to the forming of the key students’ competencies which define their success in future life. In this article, the authors’ attention focuses on a range of key competencies, educational, informational and communicative and on the possibility to develop such competencies via STEM education. This research shows the change in students’ attitude towards scientific disciplines such as mathematics, general science, technology and engineering as a result of STEM education. Two-staged analyzes questionnaires completed by students of forms II to IV in the republic of Trinidad and Tobago allowed the authors to categorize students between two levels that represent students’ attitude to various disciplines. The significance of differences between selected levels was confirmed with the use of Pearsons’ chi-squared test. In summary, the analysis of obtained data makes it possible to conclude that STEM education has a great potential for development of core students’ competencies and encourages the development of positive student attitude towards the above mentioned above scientific disciplines.

Keywords: STEM, science, technology, engineering, mathematics, students’ competency, Pearson's chi-squared test

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Authors: Haykal. Kay-Anne

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The health and well-being of students is a priority for the Faculty of Medicine at the University of Ottawa. The demands of medical studies are extreme, and many studies confirm that the prevalence of psychological distress is very high among medical students and that it is higher than that of the general population of the same age. The main goal is to identify risk factors for mental health among medical students at the University of Ottawa. The secondary objectives are to determine the variation of these risk factors according to demographic variables, as well as to determine if there is a change in the mental health of students during the 1st and 3rd years of their study. Medical students have a mandatory first and third-year wellness check meeting. This assessment includes a questionnaire on demographic information, mental health, and risk factors such as physical health, sleep, social support, financial stress, education and career, stress and drug use and/or alcohol. Student responses were converted to numerical values and analyzed statistically. The results show that 61% of the variation in the mean of the mental health score is explained by the following risk factors (R2 = 0.61, F (9.396) = 67.197, p < 0.01): lack of sleep and fatigue (β = 0.281, p < 0.001), lack of social support (β = 0.217, p <0.001), poor study or career development (β = 0.195, p < 0.001) and an increase stress and drug and alcohol use (β = -0.239, p < 0.001). No demographic variable has a significant effect on the presence of risk factors. In addition, fixed-effects regression demonstrated significantly lower mental health (p < 0.1) among first-year students (M = 0.587, SD = 0.072) than among third-year students (M = 0.719, SD = 0.071). This preliminary study indicates the need to continue data collection and analysis to increase the significance of the study results. As risk factors are present at the beginning of medical studies, it is important to offer resources to students very early in their medical studies and to have close monitoring and supervision.

Keywords: assessment of mental health, medical students, risk factors for mental health, wellness assessment

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Authors: B. Ratchaneepun, N.S. Bardell

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It is recognized that people are the main drivers in almost all the processes that affect airworthiness assurance. This is especially true in the area of aircraft maintenance, which is an essential part of continuing airworthiness. This work investigates what impact English language proficiency, the intersection of the military and Thai cultures, and the lack of initial and continuing human factors training have on the work performance of maintenance personnel in the Royal Thai Air Force (RTAF). A quantitative research method based on a cross-sectional survey was used to gather data about these three key aspects of “people” in a military airworthiness environment. 30 questions were developed addressing the crucial topics of English language proficiency, impact of culture, and human factors training. The officers and the non-commissioned officers (NCOs) who work for the Aeronautical Engineering Divisions in the RTAF comprised the survey participants. The survey data were analysed to support various hypotheses by using a t-test method. English competency in the RTAF is very important since all of the service manuals for Thai military aircraft are written in English. Without such competency, it is difficult for maintenance staff to perform tasks and correctly interpret the relevant maintenance manual instructions; any misunderstandings could lead to potential accidents. The survey results showed that the officers appreciated the importance of this more than the NCOs, who are the people actually doing the hands-on maintenance work. Military culture focuses on the success of a given mission, and leverages the power distance between the lower and higher ranks. In Thai society, a power distance also exists between younger and older citizens. In the RTAF, such a combination tends to inhibit a just reporting culture and hence hinders safety. The survey results confirmed this, showing that the older people and higher ranks involved with RTAF aircraft maintenance believe that the workplace has a positive safety culture and climate, whereas the younger people and lower ranks think the opposite. The final area of consideration concerned human factors training and non-technical skills training. The survey revealed that those participants who had previously attended such courses appreciated its value and were aware of its benefits in daily life. However, currently there is no regulation in the RTAF to mandate recurrent training to maintain such knowledge and skills. The findings from this work suggest that the people involved in assuring the continuing airworthiness of the RTAF would benefit from: (i) more rigorous requirements and standards in the recruitment, initial training and continuation training regarding English competence; (ii) the development of a strong safety culture that exploits the uniqueness of both the military culture and the Thai culture; and (iii) providing more initial and recurrent training in human factors and non-technical skills.

Keywords: aircraft maintenance, continuing airworthiness, military culture, people, Royal Thai Air Force

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Authors: Skander Ben Mami

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Despite its particular patterns and historical importance, the remote region of the Pamir Hindu Kush still lacks public recognition, as well as scientific substance, because of the abundance of classical state-centred geopolitical studies, the resilience of (inter)national narratives, and the political utility of the concepts of 'Central Asia' and 'South Asia'. However, this specific region of about 100 million inhabitants and located at the criss-cross of four geopolitical areas (Indian, Iranian, Chinese and Russian) over a territory of half a million square kilometres features a string of patterns that set it apart from the neighbouring areas of the Fergana, the Gansu and Punjab. Moreover, the Pamir Hindu Kush undergoes a series of parallel social and economic transformations that deserve scrutiny for their strong effect on the people’s lifestyle, particularly in three major urban centres (Aksu in China, Bukhara in Uzbekistan and Islamabad in Pakistan) and their immediate rural surroundings. While the involvement of various public and private stakeholders (States, NGOs, civil movements, private firms…) has undeniably resulted in positive elements (economic growth, connectivity, higher school attendance), it has in the same time generated a collection of negative effects (radicalizing, inequalities, pollution, territorial divide) that need to be addressed to strengthen regional and international security. This paper underscores the region’s strategical importance as the major hotbed and engine of insecurity and violence in Asia, notably in the context of Afghanistan’s enduring violence. It introduces the inner structures of the region, the different sources of violence as well as the governments’ responses to address it.

Keywords: geography, security, terrorism, urbanisation

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Authors: Cheng Yang Kwa, Yoke Rung Wong

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Laminated composite materials are widely employed in automotive, aerospace, and other industries. These materials provide distinct benefits due to their high specific strength, high specific modulus, and ability to be customized for a specific function. However, delamination of laminated composite materials is one of the main defects which can occur during manufacturing, regular operations, or maintenance. Delamination can bring about considerable internal damage, unobservable by visual check, that causes significant loss in strength and stability, leading to composite structure catastrophic failure. Structural health monitoring (SHM) is known to be the automated method for monitoring and evaluating the condition of a monitored object. There are several ways to conduct SHM in aerospace. One of the effective methods is to monitor the natural frequency shift of structure due to the presence of defect. This study investigated the mechanical resonance frequency shift of a multi-layer composite cantilever beam due to interlaminar delamination. ANSYS Workbench® was used to create a 4-plies laminated composite cantilever finite element model with [90/0]s fiber setting. Epoxy Carbon UD (230GPA) Prepreg was chosen, and the thickness was 2.5mm for each ply. The natural frequencies of the finite element model with various degree of delamination were simulated based on modal analysis and then validated by using literature. It was shown that the model without delamination had natural frequency of 40.412 Hz, which was 1.55% different from the calculated result (41.050 Hz). Thereafter, the various degree of delamination was mimicked by changing the frictional conditions at the middle ply-to-ply interface. The results suggested that delamination in the laminated composite cantilever induced a change in its stiffness which alters its mechanical resonance frequency.

Keywords: structural health monitoring, NDT, cantilever, laminate

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Authors: Stefano Pelaggi

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The research is focused on youth labor and mobility in Berlin. Mobility has become a common denominator in our daily lives but it does not primarily move according to monetary incentives. Labor, knowledge and leisure overlap on this point as cities are trying to attract people who could participate in production of the innovations while the new migrants are experiencing the lifestyle of the host cities. The research will present the project of empirical study focused on Italian workers in the digital industry in Berlin, trying to underline the connection between pleasure, leisure with the choice of life abroad. Berlin has become the epicenter of the European Internet start-up scene, but people suitable to work for digital industries are not moving in Berlin to make a career, most of them are attracted to the city for different reasons. This point makes a clear exception to traditional migration flows, which are always originated from a specific search of employment opportunities or strong ties, usually families, in a place that could guarantee success in finding a job. Even the skilled migration has always been originated from a specific need, finding the right path for a successful professional life. In a society where the lack of free time in our calendar seems to be something to be ashamed, the actors of youth mobility incorporate some categories of experiential tourism within their own life path. Professional aspirations, lifestyle choices of the protagonists of youth mobility are geared towards meeting the desires and aspirations that define leisure. While most of creative work places, in particular digital industries, uses the category of fun as a primary element of corporate policy, virtually extending the time to work for the whole day; more and more people around the world are deciding their path in life, career choices on the basis of indicators linked to the realization of the self, which may include factors like a warm climate, cultural environment. All indicators that are usually eradicated from the hegemonic approach to labor. The interpretative framework commonly used seems to be mostly focused on a dualism between Florida's theories and those who highlight the absence of conflict in his studies. While the flexibility of the new creative industries is minimizing leisure, incorporating elements of leisure itself in work activities, more people choose their own path of life by placing great importance to basic needs, through a gaze on pleasure that is only partially driven by consumption. The multi localism is the co-existence of different identities and cultures that do not conflict because they reject the bind on territory. Local loses its strength of opposition to global, with an attenuation of the whole concept of citizenship, territory and even integration. A similar perspective could be useful to search a new approach to all the studies dedicated to the gentrification process, while studying the new migrations flow.

Keywords: brain drain, digital industry, leisure and gentrification, multi localism

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Authors: Kin Yan Ho

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Negative brand news (such as Volkswagen’s faulty carbon emission reports, China’s Luckin Coffee scandal, and bribery in reputable US universities) influence how people perceive a company. Germany’s citizens claimed Volkswagen’s scandal as a national embarrassment and cannot recover their psychological damages through monetary and non-monetary compensation. The main research question is to examine how consumers evaluate and respond to embarrassing brand publicity. The cognitive appraisal theory is used as a theoretical foundation. This study describes the use of scenario-based experiment. The findings suggest that consumers with different levels of embarrassment evaluate brand remedial offers from emotion-focused and task-focused restorative justice perspectives (newly derived from the well-established scales of perceived justice). When consumers face both negative and positive brand information (i.e., negative publicity news and a remedial offer), they change their appraisal criterion. The social situation in the cognitive reappraisal process influences the quality of the customer-brand relationship and the customer’s recovery from brand embarrassment. The results also depict that the components of recovery compensation cause differences in emotion recovery, relationship quality, and repurchase intentions. This study extends embarrassment literature in an embarrassing brand publicity context. The emotional components of brand remedial tactics provide insights to brand managers on how to handle different consumers’ emotions, consumer satisfaction, and foster positive future behavior.

Keywords: brand relationship quality, cognitive appraisal, crisis communications, emotion, justice, social presence

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Authors: Euan Donley

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Emergency Departments (EDs) are heavily burdened as presentation rates continue to rise. To improve patient flow National Emergency Access Targets (NEAT) were introduced. NEAT implements timelines for ED presentations, such as discharging patients within four hours of arrival. Mental health patients use EDs more than the general population and are generally more complex in their presentations. The aim of this study is to examine the impact of NEAT on psychiatric risk assessment of mental health patients in the ED. Seventy-eight mental health clinicians from 7 Victoria, Australia, hospital EDs participated in a mixed method analysis via anonymous online survey. NEAT was considered helpful as mental health patients were seen quicker, were less likely to abscond, could improve teamwork amongst ED staff, and in some cases administrative processes were better streamlined. However, clinicians felt that NEAT was also responsible for less time with patients and relatives’, resulted in rushed assessments, placed undue pressure on mental health clinicians, was not conducive to training, and the emphasis on time was the wrong focus for patient treatment. The profile of a patient typically likely to be treated within NEAT timelines showed a perfect storm of luck and compliance. If a patient was sober, medically stable, referred early, did not require much collateral information and did not have distressed relatives, NEAT was more likely to be met. Organisationally participants reported no organisational change or training to meet NEAT. Poor mental health staffing, multiple ED presentations and a shortage of mental health beds also hamper meeting NEAT. Findings suggest participants were supportive of NEAT in principle, but a demanding workload and organisational barriers meant NEAT had an overall negative effect on psychiatric risk assessment of mental health patients in ED.

Keywords: assessment, emergency, risk, psychiatric

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Authors: Eunsong Lee, Gae Baik Kim, Young Pil Kim

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Bisphenol A (BPA) is one of the endocrine disruptors (EDCs), which have been suspected to be associated with reproductive dysfunction and physiological abnormality in human. Since the BPA has been widely used to make plastics and epoxy resins, the leach of BPA from the lining of plastic products has been of major concern, due to its environmental or human exposure issues. The simple detection of BPA based on the self-assembly of aptamer-mediated gold nanoparticles (AuNPs) has been reported elsewhere, yet the detection sensitivity still remains challenging. Here we demonstrate an improved AuNP-based sensor of BPA by using fluorescence-combined AuNP colorimetry in order to overcome the drawback of traditional AuNP sensors. While the anti-BPA aptamer (full length or truncated ssDNA) triggered the self-assembly of unmodified AuNP (citrate-stabilized AuNP) in the presence of BPA at high salt concentrations, no fluorescence signal was observed by the subsequent addition of SYBR Green, due to a small amount of free anti-BPA aptamer. In contrast, the absence of BPA did not cause the self-assembly of AuNPs (no color change by salt-bridged surface stabilization) and high fluorescence signal by SYBP Green, which was due to a large amount of free anti-BPA aptamer. As a result, the quantitative analysis of BPA was achieved using the combination of absorption of AuNP with fluorescence intensity of SYBR green as a function of BPA concentration, which represented more improved detection sensitivity (as low as 1 ppb) than did in the AuNP colorimetric analysis. This method also enabled to detect high BPA in water-soluble extracts from thermal papers with high specificity against BPS and BPF. We suggest that this approach will be alternative for traditional AuNP colorimetric assays in the field of aptamer-based molecular diagnosis.

Keywords: bisphenol A, colorimetric, fluoroscence, gold-aptamer nanobiosensor

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Authors: Juan de Ona, Esperanza Estevez, Rocío de Ona

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Urban traffic levels can be reduced by drawing travelers away from private vehicles over to using public transport. This modal change can be achieved by either introducing restrictions on private vehicles or by introducing measures which increase people’s satisfaction with public transport. For public transport users, quality of service affects customer satisfaction, which, in turn, influences the behavioral intentions towards the service. This paper intends to identify the main attributes which influence the perception private vehicle users have about the public transport services provided in five European cities: Berlin, Lisbon, London, Madrid and Rome. Ordinal logit models have been applied to an online panel survey with a sample size of 2,500 regular private vehicle users (approximately 500 inhabitants per city). To achieve a comprehensive analysis and to deal with heterogeneity in perceptions, 15 models have been developed for the entire sample and 14 user segments. The results show differences between the cities and among the segments. Madrid was taken as reference city and results indicate that the inhabitants are satisfied with public transport in Madrid and that the most important public transport service attributes for private vehicle users are frequency, speed and intermodality. Frequency is an important attribute for all the segments, while speed and intermodality are important for most of the segments. An analysis by segments has identified attributes which, although not important in most cases, are relevant for specific segments. This study also points out important differences between the five cities. Findings from this study can be used to develop policies and recommendations for persuading.

Keywords: service quality, satisfaction, public transportation, private vehicle users, car users, segmentation, ordered logit

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Authors: Akudo Ejelonu, Sarah Willig, J. Anthony Sauder, Heather Murphy, Frances Shofer

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Background: The high prevalence of diarrheal diseases in the village of Tzununá, Guatemala is linked to lack of sanitation facilities and handwashing practices. Diarrheal diseases are preventable and improved access to latrines, hygiene education and clean water may improve sanitation by reducing the spread of disease. Objective: Between May 2015-January 2017, the University of Pennsylvania Chapter of Engineers Without Border (PennEWB) and local partners designed an intervention to reduce diarrheal disease by building pour flush latrines in 50 individual households and providing education on the importance of handwashing practice. Design/Methods: Through convenient sampling, we surveyed 45 households to evaluate the community’s knowledge of diarrheal disease, handwashing practices, and maintenance of the latrines. Results: 92% of the study participants experienced decrease of new cases of diarrheal disease after receiving a latrine. Only 11% washed their hands after defecating in the latrine. There was gap in understanding the health outcome of latrine sanitation and handwashing education. The respondents did not connect the reduction of diarrheal disease with latrine use and maintenance. Instead, they associated their motivation for latrine use with aesthetics, proximity to their home, ease and comfort, and reduction of shame. We recommend that PennEWB adopt UNICEF or WHO education on hand washing practice. Conclusion: Social interaction and social pressure drove the household use of latrines. The latrines are being valued and cleaned. The education that the residents received did not target norms and behaviors. Latrines could be used to create a new social norm that supports behavioral change.

Keywords: diarrheal disease, latrine, open defecation, water, sanitation and hygiene

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Authors: Soufiane Fal, Abderahim Aasfar, Ali Ouhssain, Hasnae Choukri, Abelaziz Smouni, Hicham El Arroussi

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Heavy metals contamination is a major environmental concern around the world. It has a harmful impact on plant productivity and poses a serious risk to humans and animals health. In the present study, the effect of Microalgae Crude Extract (MCE) on tomato growth and nutrients uptake exposed to 2 mM Pb2+ and Cd2+ was investigated. In results, 2 mM Pb2+ and Cd2+ showed a significant reduction of tomatobiomass and perturbation in nutrients absorption. Moreover, MCE application in tomato plant exposed to Pb2+ and Cd2+ showed a significant enhancement of biomass compared to tomato plants under Pb2+ and Cd2+. On the other hand, MCE application favoured heavy metals accumulation in root and inhibited their translocation to shoot as phytostabilisation mechanism. Tomato plants showed biochemical responses to Pb2+ and Cd2+ stress with elevation of scavenging enzymes and molecules such as POD, CAT, SOD, Proline, and polyphenols, etc. In addition, the treatment by MCE showed a significant reduction level of the majority of these parameters. Furthermore, the metabolomic analysis revealed a significant change in important metabolites. Pb2+ and Cd2+ showed decrease in SFA and increase of UFA, VLFA, alkanes, alkenes, sterols, which known accumulated as tolerance and resistance mechanism to heavy metal (H.M) stress. However, MCE treatment showed the inverse of these response to return tomato plants to normal state and enhanced tolerance and resistance to heavy metal stress. In the present study, we emphasized that MCE can alleviate H.M stress, enhance tomato plant growth nutrients absorption and improve biochemical responses.

Keywords: microalgae crude extract, heavy metal stress, nutrient uptake, metabolomic analysis, solanum lycopersicum (Tomato), phytostabilisation

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Authors: Amel M. A. Osman, Roy Mahony, Lisa Dann, McKenna S.

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Background: Computed Tomography (CT) is a significant source of radiation in the pediatric population. A new head injury (HI) pathway was introduced in 2021, which altered the previous process of HI being jointly admitted with general pediatrics and surgery to admit these patients under the Emergency Medicine Team. Admitted patients included those with positive CT findings not requiring immediate neurosurgical intervention and those who did not meet current criteria for urgent CT brain as per NICE guidelines but were still symptomatic for prolonged observations. This approach aims to decrease the number of CT scans performed. The main aim is to assess the variation in CT scanning rates since the change in the admitting process. A retrospective review of patients presenting to CHI PECU with HI over 6-month period (01/01/19-31/05/19) compared to a 6-month period post introduction of the new pathway (01/06/2022-31/12/2022). Data was collected from the electronic record databases, symphony, and PACS. Results: In 2019, there were 869 presentations of HI, among which 32 (3.68%) had CT scans performed. 2 (6.25%) of those scanned had positive findings. In 2022, there were 1122 HI presentations, with 47 (4.19%) CT scans performed and positive findings in 5 (10.6%) cases. 57 patients were admitted under the new pathway for observation, with 1 having a CT scan following admission. Conclusion: Quantitative lifetime radiation risks for children are not negligible. While there was no statistically significant reduction in CTs performed amongst HIs presenting to our department, a significant group met the criteria for admission under the PECU consultant for prolonged monitoring. There was also a greater proportion of abnormalities on CT scans performed in 2022, demonstrating improved patient selection for imaging. Further data analysis is ongoing to determine if those who were admitted would have previously been scanned under the old pathway.

Keywords: head injury, CT, admission, guidline

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Authors: Nongyao Intasaso, Atchara Rattanama, Navarat Pewnual

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This research is survey research purposed to study the factor affected to knowledge management efficiency of personnel in Rajamangala University of Technology Srivijaya, and study the problem of knowledge management affected to knowledge development of personnel in the university. The tool used in this study is structures questioner standardize rating scale in 5 levels. The sample selected by purposive sampling and there are 137 participation calculated in 25% of population. The result found that factor affected to knowledge management efficiency in the university included (1) result from the organization factor found that the university provided project or activity that according to strategy and mission of knowledge management affected to knowledge management efficiency in highest level (x̅ = 4.30) (2) result from personnel factor found that the personnel are eager for knowledge and active to learning to develop themselves and work (Personal Mastery) affected to knowledge management efficiency in high level (x̅ = 3.75) (3) result from technological factor found that the organization brought multimedia learning aid to facilitate learning process affected to knowledge management efficiency in high level (x̅ = 3.70) and (4) the result from learning factor found that the personnel communicated and sharing knowledge and opinion based on acceptance to each other affected to knowledge management efficiency in high level (x̅ = 3.78). The problem of knowledge management in the university included the personnel do not change their work behavior, insufficient of collaboration, lack of acceptance in knowledge and experience to each other, and limited budget. The solutions to solve these problems are the university should be support sufficient budget, the university should follow up and evaluate organization development based on knowledge using, the university should provide the activity emphasize to personnel development and assign the committee to process and report knowledge management procedure.

Keywords: knowledge management, efficiency, personnel, learning process

Procedia PDF Downloads 301

Authors: Natalia Politaeva, Iuliia Smiatskaia, Iuliia Bazarnova, Iryna Atamaniuk, Kerstin Kuchta

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Nowadays, the progressive decrease of primary natural resources and ongoing upward trend in terms of energy demand, have resulted in development of new generation technological processes which are focused on step-wise production and residues utilization. Thus, microalgae-based 3^rd generation bioeconomy is considered one of the most promising approaches that allow production of value-added products and sophisticated utilization of residues biomass. In comparison to conventional biomass, microalgae can be cultivated in wide range of conditions without compromising food and feed production, and thus, addressing issues associated with negative social and environmental impacts. However, one of the most challenging tasks is to undergo seasonal variations and to achieve optimal growing conditions for indoor closed systems that can cover further demand for material and energetic utilization of microalgae. For instance, outdoor cultivation in St. Petersburg (Russia) is only suitable within rather narrow time frame (from mid-May to mid-September). At earlier and later periods, insufficient sunlight and heat for the growth of microalgae were detected. On the other hand, without additional physical effects, the biomass increment in summer is 3-5 times per week, depending on the solar radiation and the ambient temperature. In order to increase biomass production, scientists from all over the world have proposed various technical solutions for cultivators and have been studying the influence of various physical factors affecting biomass growth namely: magnetic field, radiation impact, and electric field, etc. In this paper, the influence of infrared radiation (IR) and fluorescent light on the growth rate of microalgae Chlorella sorokiniana has been studied. The cultivation of Chlorella sorokiniana was carried out in 500 ml cylindrical glass vessels, which were constantly aerated. To accelerate the cultivation process, the mixture was stirred for 15 minutes at 500 rpm following 120 minutes of rest time. At the same time, the metabolic needs in nutrients were provided by the addition of micro- and macro-nutrients in the microalgae growing medium. Lighting was provided by fluorescent lamps with the intensity of 2500 ± 300 lx. The influence of IR was determined using IR lamps with a voltage of 220 V, power of 250 W, in order to achieve the intensity of 13 600 ± 500 lx. The obtained results show that under the influence of fluorescent lamps along with the combined effect of active aeration and variable mixing, the biomass increment on the 2^nd day was three times, and on the 7^th day, it was eight-fold. The growth rate of microalgae under the influence of IR radiation was lower and has reached 22.6·10⁶ cells·mL^-1. However, application of IR lamps for the biomass growth allows maintaining the optimal temperature of microalgae suspension at approximately 25-28°C, which might especially be beneficial during the cold season in extreme climate zones.

Keywords: biomass, fluorescent lamp, infrared radiation, microalgae

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Authors: Krishna Prasad Maity, Narendra Tanty, Ananya Patra, V. Prasad

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Carbon nanotube (CNT) is a well-known material for very good electrical, thermal conductivity and high tensile strength. Because of that, it’s widely used in many fields like nanotechnology, electronics, optics, etc. In last two decades, polyaniline (PANI) with CNT and functionalized CNT (fCNT) have been promising materials in application of gas sensing, electromagnetic shielding, electrode of capacitor etc. So, the study of electrical conductivity of PANI/CNT and PANI/fCNT is important to understand the charge transport and interaction between PANI and CNT in the composite. It is observed that a transition in magnetoresistance (MR) with lowering temperature, increasing magnetic field and decreasing CNT percentage in CNT/PANI composite. Functionalization of CNT prevent the nanotube aggregation, improves interfacial interaction, dispersion and stabilized in polymer matrix. However, it shortens the length, breaks C-C sp² bonds and enhances the disorder creating defects on the side walls. We have studied electrical resistivity and MR in PANI with CNT and fCNT composites for different weight percentages down to the temperature 4.2K and up to magnetic field 5T. Resistivity increases significantly in composite at low temperature due to functionalization of CNT compared to only CNT. Interestingly a transition from negative to positive magnetoresistance has been observed when the filler is changed from pure CNT to functionalized CNT after a certain percentage (10wt%) as the effect of more disorder in fCNT/PANI composite. The transition of MR has been explained on the basis of polaron-bipolaron model. The long-range Coulomb interaction between two polarons screened by disorder in the composite of fCNT/PANI, increases the effective on-site Coulomb repulsion energy to form bipolaron which leads to change the sign of MR from negative to positive.

Keywords: coulomb interaction, magnetoresistance transition, polyaniline composite, polaron-bipolaron

Procedia PDF Downloads 172