Search results for: nanoparticle physical characteristics

Authors: Timilehin Martins Oyinloye, Won Byong Yoon

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Simulation technology is being adopted in many industries, with research focusing on the development of new ways in which technology becomes embedded within production, services, and society in general. 3D printing (3DP) technology is fast developing in the food industry. However, the limited processability of high-performance material restricts the robustness of the process in some cases. Significantly, the printability of materials becomes the foundation for extrusion-based 3DP, with residual stress being a major challenge in the printing of complex geometry. In many situations, the trial-a-error method is being used to determine the optimum printing condition, which results in time and resource wastage. In this report, the analysis of 3 moisture levels for surimi paste was investigated for an optimum 3DP material and printing conditions by probing its rheology, flow characteristics in the nozzle, and post-deposition process using the finite element method (FEM) model. Rheological tests revealed that surimi pastes with 82% moisture are suitable for 3DP. According to the FEM model, decreasing the nozzle diameter from 1.2 mm to 0.6 mm, increased the die swell from 9.8% to 14.1%. The die swell ratio increased due to an increase in the pressure gradient (1.15107 Pa to 7.80107 Pa) at the nozzle exit. The nozzle diameter influenced the fluid properties, i.e., the shear rate, velocity, and pressure in the flow field, as well as the residual stress and the deformation of the printed sample, according to FEM simulation. The post-printing stability of the model was investigated using the additive layer manufacturing (ALM) model. The ALM simulation revealed that the residual stress and total deformation of the sample were dependent on the nozzle diameter. A small nozzle diameter (0.6 mm) resulted in a greater total deformation (0.023), particularly at the top part of the model, which eventually resulted in the sample collapsing. As the nozzle diameter increased, the accuracy of the model improved until the optimum nozzle size (1.0 mm). Validation with 3D-printed surimi products confirmed that the nozzle diameter was a key parameter affecting the geometry accuracy of 3DP of surimi paste.

Keywords: 3D printing, deformation analysis, die swell, numerical simulation, surimi paste

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Authors: Yanqun Li, Hong Geng

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The rapid urbanization process taking big cities as the main body leads to the unequal configuration of urban and rural areas in the aspects of land supply, industrial division of labor, service supply and space allocation, and induces the shrinking characterization of service energy, industrial system and population vitality in small towns. As an important spatial unit in the spectrum of urbanization that serves, connects and couples urban and rural areas, the shrinking phenomenon faced by small towns has an important influence on the healthy development of urbanization. Based on the census of small towns in Wuhan metropolitan area, we have found that the shrinking of small towns is a passive contraction of elastic tension under the squeeze in cities. Once affected by the external forces such as policy regulation, planning guidance, and population return, small towns will achieve expansion and growth. Based on the theory of complex adaptive systems, this paper comprehensively constructs the development index evaluation system of small towns from five aspects of population, economy, space, society and ecology, measures the shrinking level of small towns, further analyzes the shrinking characteristics of small towns, and identifies whether the shrinking is elastic or not. And then this paper measures the resilience ability index of small town contract from the above-mentioned five aspects. Finally, this paper proposes an adaptive mechanism of urban-rural interaction evolution under fine division of labor to response the passive shrinking in small towns of Wuhan. Based on the above, the paper creatively puts forward the planning response measures of the small towns on the aspects of spatial layout, function orientation and service support, which can provide reference for other regions.

Keywords: complex adaptive systems, resiliency shrinking, adaptation mechanism, planning response

Procedia PDF Downloads 113

Authors: Mehmet Uysal, Yavuz Arat, Uğur Tuztaşı

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As man constructed the spaces that he lived in he also designed spaces where their dead will stay according to their belief systems. These spaces are sometimes monumentalized by the means of a stone on the top of a mountain, sometimes signed by totems and sometimes became structures to protect graves and symbolize the person or make him unforgettable. Various grave monuments have been constructed from the earliest primitive societies to developed societies. Every belief system built structures for itself; Pyramids for pharaohs, grave monuments for kings and emperors, temples and tombs for important men of religion. These spaces are also architectural works like a school or a dwelling and have importance in history of architecture. After Turks embraced Islamism, examples of very beautiful tombs are built in Middle Asia during the Seljuk Period. By the time Seljuks came to Anatolia they built important tombs having peerless architectural characteristics firstly around Ahlat. After Anatolia Seljuks made Konya the capital city and Konya became administrative, cultural and scientific center, very important tombs were built in Konya. Different from the local tomb architecture, the architecture of tombs with half-open “eyvan/Iwan” is significant. Although iwan buildings is vastly used in Anatolian civil architecture and monumental buildings its best exmaples are observed in 13th century Medrese buildings. The iwan tomb tradition which was observed during the time period when this building typology was shaped and departed from the resident tradition in the form of iwan tombs are rarely represented. However, similar tombs were build in resemblance to this tradition. This study provides information on samples of iwan tombs (Gömeç Hatun Tomb, Emir Yavaştagel Tomb, and Beşparmak Tomb) and evaluates the departures from iwan building complexes in view of architectural language. This paper also gives information about iwan tombs among tombs having importance in Islamic Architectural Heritage.

Keywords: Seljuk Building Complex, Eyvan/Iwan, Anatolia, Islamic Architectural Heritage, tomb

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Authors: M. Reyes, R. Sastre, P. Gabana, F. V. Tinaut

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In this work, an optical characterization of the ethanol-air laminar combustion is presented in order to investigate the origin of the instabilities developed during the combustion, the onset of the cellular structure and the laminar burning velocity. Experimental tests of ethanol-air have been developed in an optical cylindrical constant volume combustion bomb equipped with a Schlieren technique to record the flame development and the flame front surface wrinkling. With this procedure, it is possible to obtain the flame radius and characterize the time when the instabilities are visible through the cell's apparition and the cellular structure development. Ethanol is an aliphatic alcohol with interesting characteristics to be used as a fuel in Internal Combustion Engines and can be biologically synthesized from biomass. Laminar burning velocity is an important parameter used in simulations to obtain the turbulent flame speed, whereas the flame front structure and the instabilities developed during the combustion are important to understand the transition to turbulent combustion and characterize the increment in the flame propagation speed in premixed flames. The cellular structure is spontaneously generated by volume forces, diffusional-thermal and hydrodynamic instabilities. Many authors have studied the combustion of ethanol air and mixtures of ethanol with other fuels. However, there is a lack of works that investigate the instabilities and the development of a cellular structure in ethanol flames, a few works as characterized the ethanol-air combustion instabilities in spherical flames. In the present work, a parametrical study is made by varying the fuel/air equivalence ratio (0.8-1.4), initial pressure (0.15-0.3 MPa) and initial temperature (343-373K), using a design of experiments type I-optimal. In reach mixtures, it is possible to distinguish the cellular structure formed by the hydrodynamic effect and by from the thermo-diffusive. Results show that ethanol-air flames tend to stabilize as the equivalence ratio decreases in lean mixtures and develop a cellular structure with the increment of initial pressure and temperature.

Keywords: ethanol, instabilities, premixed combustion, schlieren technique, cellularity

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Authors: Rotem Mashkov, Noam Shoval

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In an age when a tourist’s gaze is more focused on the daily lives of locals, it is evident that local food markets are being rediscovered. Traditional urban markets succeed in reinventing themselves as a space for consumption, recreation, and culture, enabling authentic experiences and interpersonal interactions with the local culture. Alongside this, the pressure of tourism development may result in commercialization and retail gentrification to the point of losing the sense of local identity. The issue of finding a balance between tourism development and the preservation of unique local features is at the heart of this study and is being tested using the case of the Mahane Yehuda market in Jerusalem. The research question—how merchants respond to tourism development in the Mahane Yehuda food market— focuses on local traders, a group of players who are usually absent from the research arenas, although they influence tourism development as well as influenced by it. Three main research methods were integrated into this study. The first two methods, a survey of articles survey and comparative mapping of the business mix, were used to characterize the changes in the Mahane Yehuda market both consciously and physically. The third research method, involving in-depth interviews with merchants, was used to examine the traders' attitudes and responses to tourism development. The findings indicate that there has been a turnaround in the market image over the past decade and a half. Additionally, there has been a significant physical change in the business mix, reflected by a decline of 15% in the number of stalls selling food products and delicacies. The data from the interviews on the traders’ attitudes towards tourism development were inconclusive; there were disagreements among the traders about the economic contribution of tourism development in relation to their dependence on the tourism industry. However, there was a consensus on the need for authentic elements in the marketplace. The findings of the study also indicate a strong link between the merchants’ response to tourism development and their stall ownership status as the merchant could exercise their position in various ways depending on the possession type.

Keywords: business mix, Jerusalem, local food markets, Mahane Yehuda market, merchants’ attitude, ownership status, retail gentrification, tourism development, traditional urban markets

Procedia PDF Downloads 133

Authors: Sara Alzahrani, Samia Bokari, Patan Khan, Muneera Alshareef, Rania Safwat, Mohammed Galal, Hamdi Alqadi, Ameerah Alzahrani, Rehab Alboraie

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Introduction & Background: Diabetes in COVID-19 patients is individual risk factor and documented in worldwide studies to contribute to disease severity, increased length of stay and higher mortality. Aggressive management of blood sugars and acute diabetic complications reduce the length of stay and mortality. Methods: Randomly selected 200 patients admitted with diabetes and COVID-19 studied. The unified treatment protocol applied for all patients and blood sugars monitored closely and optimized .Data collected on bimonthly basis and analyzed. Patients’ characteristics taken from data extraction tool (Oasis) of hospital. Median values for length of stay and post discharge FBS and RBS were calculated via Microsoft Excel tool. Mortality rates were calculated by percentages. The results monitored in the post discharge clinic was 130 mg/dl and 170 mg/dl respectively. The results compared with the standard international studies. Discussion: Diabetes in COVID-19 patients posed great challenge as increased severity and mortalities reported compared to non-diabetic. Taking a pre-emptive strategy to combat this problem by aggressively manage diabetes help in reducing length of stay and morbidity. The length of stay in studded population was 3 days as compared to 13 days in a major international study. Financial saving come from rapid turnover of beds. The mortality was 2.5 % compared to reported 7.3% in a major study, reflecting the implications of aggressive management of diabetes. Regular follow-up and support by running post-discharge clinic definitely help reducing readmissions and acute complications of uncontrolled diabetes. Conclusion: Aggressive management of diabetes in COVID-19 patients by tailored treatment protocols and dedicated teams will help to decrease the morbidity and mortality.

Keywords: diabetes, covid-19, management, mortality

Procedia PDF Downloads 175

Authors: Ilse Gonzalez-Rivera, Rolando Diaz-Loving

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Family, and parents in particular, are the main agents of socialization of children since they transmit values, beliefs, and cultural norms based on their own guidelines, so that children acquire the knowledge on how to interact with others in terms of the interaction with their parents. One way to measure socialization parenting is through parenting styles. Parenting styles are the set of parental behaviors that have a direct effect on the development of specific behaviors of children. The ideal parenting style depends on the cultural characteristics where people develop. In Mexico, the hierarchical structure of the family is built on a model in which men are dominant over women and their power is legitimized. This research explores the effect of parenting styles and the culture of the ambivalent sexism in the Mexican population. 150 men and 150 women participated. The instrument of individualism-collectivism was used to measure culture; participants also answered the instrument of ambivalent sexism and the parenting styles questionnaire. Regression analyses were done using sexism as the dependent variable and individualism-collectivism and parenting styles as independent variables. In addition, an analysis of variance between parental styles and gender of the participants was performed. The results indicate that the permissive style and authoritarian style are predictors of ambivalent sexism and higher levels of collectivism predict higher levels of sexism in both men and women. It is also found that parents tend to use authoritarian parenting style with women and permissive style with males. These results confirm the findings of other studies that indicate that parenting is an important variable that influences the interaction of adults. On the other hand, the effect of collectivism on sexism may be related to the fact that gender Mexican rules are rigid and for people with higher levels of collectivism, the social rules are more important than individual interests. In conclusion, these results indicate that both culture and parenting styles contribute to the maintenance of the status quo and prejudice towards women. Therefore, it is necessary to create proposals that break with this cultural paradigm and to further develop democratic styles of parenting with the aim of reducing prejudice and the legitimization of gender roles.

Keywords: culture, gender, parenting style, sexism

Procedia PDF Downloads 258

Authors: Dorsa Moayedi

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‘The Cities’ and Cinema have a history going as far back as silent films; however, the standards of picturing a city in a film are somewhat vague. ‘Genius Loci’ of a city can be easily described with parameters that architects have detected; nevertheless, the genius loci of an ‘urban movie’ is untouched. Cities have been among the provocative matters that pushed filmmakers to ponder upon them and to picture them along with their urban identity thoroughly in their artworks, though the impacts of the urban life on the plot and characters is neglected, and so a city in a movie is usually restricted to ‘the place where the story happens’. Cities and urban life are among those that are in constant change and ongoing expansion; therefore, they are always fresh and ready to challenge people with their existence. Thus, the relationship between the city and cinema is metamorphic, though it could be defined and explored. The dominant research on the idea of urbanism has been conducted by outstanding scholars of architecture, like Christian Norberg-Schulz, and the studies on Cinema have been done by theorists of cinema, like Christian Metz, who have mastered defining their own realm; still, the idea to mingle the domains to reach a unified theory which could be applied to ‘urban movies’ is barely worked on. In this research, we have sought mutual grounds to discuss ‘urbanism in cinema,’ the grounds that cinema could benefit from and get to a more accurate audio-visual representation of a city, in accordance with the ideas of Christopher Alexander and the term he coined ‘The Timeless Way of Building.’ We concentrate on movies that are dependent on urban life, mainly those that possess the names of cities, like ‘Nashville (1975), Manhattan (1979), Fargo (1996), Midnight in Paris (2011) or Roma (2018), according to the ideas of urban design and narratives of cinema. Contrary to what has often been assumed, cinema and architecture could be defined in line with similar parameters, and architectural terms could be applied to the research done on movies. Our findings indicate that the theories of Christopher Alexander can best fit the paradigm to study an ‘Urban Movie’, definitions of a timeless building, elaborate on the characteristics of a design that could be applied to definitions of an urban movie, and set a prototype for further filmmaking regarding the urban life.

Keywords: city, urbanism, urban movies, identity, representation

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Authors: Faisal Mahroogi, Mahmoud Bady, Yaser H. Alahmadi, Ahmed Alsisi, Sunny Narayan, Muhammad Usman Kaisan

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The Kingdom of Saudi Arabia established Saudi Vision 2030, an initiative of the government with the goal of promoting more socioeconomic as well as cultural diversity. The kingdom, which is dedicated to sustainable development and clean energy, uses cutting-edge approaches to address energy-related issues, including the circular carbon economy (CCE) and a more varied energy mix. In order for Saudi Arabia to achieve its Vision 2030 goal of having a net zero future by 2060, sustainability is essential. By addressing the energy and climate issues of the modern world with responsibility and innovation, Vision 2030 is turning into a global role model for the transition to a sustainable future. As per the Ambitions of the National Environment Strategy of the Saudi Ministry of Environment, Agriculture, and Water (MEWA), raising environmental compliance across all sectors and reducing pollution and adverse environmental impacts are critical focus areas. As a result, the current study presents an experimental analysis of the performance and exhaust emissions of a diesel engine running mostly on waste cooking oil (WCO). A one-cylinder direct-injection diesel engine with constant speed and natural aspiration is the engine type utilized. Research was done on how the engine performed and emission parameters when fueled with a mixture of 10% butanol, 10% diesel, 10% WCO, and 10% diethyl ether (D70B10W10DD10). The study's findings demonstrated that engine emissions of nitrogen oxides (NOX) and carbon monoxide (CO) varied significantly depending on the load being applied. The brake thermal efficiency, cylinder pressure, and the brake power of the engine were all impacted by load change.

Keywords: ICE, waste cooking oil, fuel additives, butanol, combustion, emission characteristics

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Authors: Bojana Horvat, Barbara Karleusa, Goran Volf, Nevenka Ozanic, Ivica Kisic

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Forest fire is a major threat in many regions in Croatia, especially in coastal areas. Although they are often caused by natural processes, the most common cause is the human factor, intentional or unintentional. Forest fires drastically transform landscapes and influence natural processes. The main goal of the presented research is to analyse and quantify the impact of the forest fire on hydrological processes and propose the model that best describes changes in hydrological patterns in the analysed catchments. Keeping in mind the spatial component of the processes, geospatial analysis is performed to gain better insight into the spatial variability of the hydrological response to disastrous events. In that respect, two catchments that experienced severe forest fire were delineated, and various hydrological and meteorological data were collected both attribute and spatial. The major drawback is certainly the lack of hydrological data, common in small torrential karstic streams; hence modelling results should be validated with the data collected in the catchment that has similar characteristics and established hydrological monitoring. The event chosen for the modelling is the forest fire that occurred in July 2019 and burned nearly 10% of the analysed area. Surface (land use/land cover) conditions before and after the event were derived from the two Sentinel-2 images. The mapping of the burnt area is based on a comparison of the Normalized Burn Index (NBR) computed from both images. To estimate and compare hydrological behaviour before and after the event, curve number (CN) values are assigned to the land use/land cover classes derived from the satellite images. Hydrological modelling resulted in surface runoff generation and hence prediction of hydrological responses in the catchments to a forest fire event. The research was supported by the Croatian Science Foundation through the project 'Influence of Open Fires on Water and Soil Quality' (IP-2018-01-1645).

Keywords: Croatia, forest fire, geospatial analysis, hydrological response

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Authors: Kamila Troper, Pedro Mestre, Maria Lurdes Menano, Joana Mendonça, Maria João Costa, Sandra Demel

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Introduction: Visual impairment is a problem that has an influence on hundreds of thousands of people all over the world. Although it is possible for a Visually Impaired person to do most jobs, the right training, technological assistance, and emotional support are essential. Ergonomics be able to solve many of the problems/issues with the relative ease of positioning, lighting and design of the workplace. A little forethought can make a tremendous difference to the ease with which a person with an impairment function. Objectives: Review the main ergonomic adaptation measures reported in the literature in order to promote better working conditions and safety measures for the visually impaired. Methodology: This was an exploratory-descriptive, qualitative literature systematic review study. The main databases used were: PubMed, BIREME, LILACS, with articles and studies published between 2000 and 2021. Results: Based on the principles of the theoretical references of ergonomic analysis of work, the main restructuring of the physical space of the workstations were: Accessibility facilities and assistive technologies; A screen reader that captures information from a computer and sends it in real-time to a speech synthesizer or Braille terminal; Installations of software with voice recognition, Monitors with enlarged screens; Magnification software; Adequate lighting, magnifying lenses in addition to recommendations regarding signage and clearance of the places where the visually impaired pass through. Conclusions: Employability rates for people with visual impairments(both those who are blind and those who have low vision)are low and continue to be a concern to the world and for researchers as a topic of international interest. Although numerous authors have identified barriers to employment and proposed strategies to remediate or circumvent those barriers, people with visual impairments continue to experience high rates of unemployment.

Keywords: ergonomic adaptations, visual impairments, ergonomic analysis of work, systematic review

Procedia PDF Downloads 178

Authors: Yung C. Lin, Kung D. Wu, Wei C. Shih, Jui P. Hung

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High speed and high precision machining have become the most important technology in manufacturing industry. The surface roughness of high precision components is regarded as the important characteristics of the product quality. However, machining chatter could damage the machined surface and restricts the process efficiency. Therefore, selection of the appropriate cutting conditions is of importance to prevent the occurrence of chatter. In addition, vibration of the spindle tool also affects the surface quality, which implies the surface precision can be controlled by monitoring the vibration of the spindle tool. Based on this concept, this study was aimed to investigate the influence of the machining conditions on the surface roughness and the vibration of the spindle tool. To this end, a series of machining tests were conducted on aluminum alloy. In tests, the vibration of the spindle tool was measured by using the acceleration sensors. The surface roughness of the machined parts was examined using white light interferometer. The response surface methodology (RSM) was employed to establish the mathematical models for predicting surface finish and tool vibration, respectively. The correlation between the surface roughness and spindle tool vibration was also analyzed by ANOVA analysis. According to the machining tests, machined surface with or without chattering was marked on the lobes diagram as the verification of the machining conditions. Using multivariable regression analysis, the mathematical models for predicting the surface roughness and tool vibrations were developed based on the machining parameters, cutting depth (a), feed rate (f) and spindle speed (s). The predicted roughness is shown to agree well with the measured roughness, an average percentage of errors of 10%. The average percentage of errors of the tool vibrations between the measurements and the predictions of mathematical model is about 7.39%. In addition, the tool vibration under various machining conditions has been found to have a positive influence on the surface roughness (r=0.78). As a conclusion from current results, the mathematical models were successfully developed for the predictions of the surface roughness and vibration level of the spindle tool under different cutting condition, which can help to select appropriate cutting parameters and to monitor the machining conditions to achieve high surface quality in milling operation.

Keywords: machining parameters, machining stability, regression analysis, surface roughness

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Authors: Gudakesh Yadav

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Utter Pradesh, which is one of the largest states of India with unequal distribution of resources and different socioeconomic and cultural characteristics, level of different new born health care indicators varies a lot from one district to another district. State shared more than 21 percent of total live births of India; whereas, it accounts for 28 percent of total infant deaths of the country, with the 53 per thousand infant mortality rate. The present paper attempts to examine tempo-spatial changes in new born care practices during NFHS-1 to NFHS-3 and DLHS-2 to DLHS-3 in Uttar Pradesh and different regions. Descriptive statistics, rate-ratios, concentration index, multivariate and decomposition analysis has been used for the study. Findings of the study reveal that new born care practices have improved over the time in the state and across all the regions because of giving more emphasis on venerable groups like poor, rural, less educated mothers and scheduled caste & tribes but still it did not achieve the desired successes. Regional analysis of third rounds of DLHS shows that, coverage of intuitional delivery was the lowest in the central region. Performance of the southern region was the lowest in terms of initiation of breastfeeding, keeping baby warm and dry after the birth. The study calls for proper follow up of new born children to accelerate new born and child health care service and prioritises increasing antenatal check-ups and institutional delivery, which helps to improve level of other new born care services. At the policy level there is need to reach venerable groups like scheduled caste and tribes, poor and uneducated, and new mother especially in rural areas. High focused district should be allocated for better implementation of new born care promotion programme in low performing districts. Partnership with the private sector health professional is necessary to reach the every part of population.

Keywords: decomposition, inequality, initiation of breastfeeding, institutional delivery

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Authors: Islam Abouelhamd

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Rives have long been recognized as one of the most important natural resources, They are important to ensure human health, civilization, and sustainable development, and the importance of rivers as the focal point of cities was established from the early times of civilization and will remain so. Urban design of Riverfront has been an issue of wide concern and extensive discussion since the 1970s, however, Cities seek a riverfront that is a place of public enjoyment, They want a Riverfront where there is ample visual and physical public access to both the water and the land, they want a place that contributes to the quality of life in all of its aspects; economic, social, and cultural, on another hand, Successful urban design of Riverfront requires an understanding of development processes, dimensions of urban design and an appreciation of the distinctiveness of Riverfront locations. A close association between cities and river is inherently over the history of civilization, and in fact, many urban cities in Egypt are located close to Nile River areas. Always trying to use the land closer to the river to take advantage of the benefits it provides, And in spite of the significant role played by the littoral fronts in the life of the city, the riverfronts have remained generally in Egypt and especially in Asyut city neglected. According to the knowledge gained from the literature review, review of case studies and the historical researches of Asyut Riverfront, this research aims to identify the urban transformations of Asyut riverfront and expect the Opportunities and Challenges which will play an important part of the future urban design issues and researches will prepare, especially in the case study area (northern areas of Asyut riverfront). After that, the case study data, historical framework and International experiences were collected and analyzed to Produce Primary indicators of the expectations of the riverfront urban design process inside the case study area, In addition to preparing the conclusions of the theoretical framework and recommendations for the paper.

Keywords: civilization, sustainable development, riverfront, urban transformations

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Authors: Na Zhou, Chun-Lai Zhang, Qing Li, Bingqi Zhu, Xun-Ming Wang

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The understanding of the dynamics of aeolian sand in the Yarlung Zangbo River Valley (YLZBV), southern Qinghai-Tibetan Plateau, including its origins, transportation,and deposition, remains preliminary. In this study, we investigated the extensive origin of aeolian sediments in the YLZBV by analyzing the distribution and composition of sediment’s grain size and geochemical composition in dune sediments collected from the wide river terraces. The major purpose is to characterize the sedimentological and geochemical compositions of these aeolian sediments, trace back to their sources, and understand their influencing factors. As a result, the grain size and geochemistry variations, which showed a significant correlation between grain sizes distribution and element abundances, give a strong evidence that the important part of the aeolian sediments in the downstream areas was firstly derived from the upper reaches by intense fluvial processes. However, the sediments experienced significant mixing process with local inputs and reconstructed by regional wind transportation. The diverse compositions and tight associations in the major and trace element geochemistry between the up- and down-stream aeolian sediments and the local detrital rocks, which were collected from the surrounding mountains, suggest that the upstream aeolian sediments had originated from the various close-range rock types, and experienced intensive mixing processes via aeolian- fluvial dynamics. Sand mass transported by water and wind was roughly estimated to qualify the interplay between the aeolian and fluvial processes controlling the sediment transport, yield, and ultimately shaping the aeolian landforms in the mainstream of the YLZBV.

Keywords: grain size distribution, geochemistry, wind and water load, sand source, Yarlung Zangbo River Valley

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Authors: Dalila Lino, Maria Joao Hortas, Carla Rocha, Clarisse Nunes, Natalia Vieira, Marina Fuertes, Kátia Sa

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The value of play is recognized worldwide and is considered a fundamental right of all children, as defined in Article 31 of the United Nations Children’s Rights. It is consensual among the scientific community that play, and toys are of vital importance for children’s learning and development. Play promotes the acquisition of language, enhances creativity and improves social, affective, emotional, cognitive and motor development of young children. Young children ages 0 to 6 who have had many opportunities to get involved in play show greater competence to adapt to new and unexpected situations and more easily overcome the pain and suffering caused by traumatic situations. The PlayTrain Project aims to understand the places/spaces of play in the education of children from 0 to 6 years and promoting the training of preschool teachers to become capable of developing practices that enhance children’s agency, experimentation in the physical and social world and the development of imagination and creativity. This project follows the Design-Based-Research (DBR) and has two dimensions: research and intervention. The participants are 120 students from the Master in Pre-school Education of the Higher School of Education, Polytechnic Institute of Lisbon enrolled in the academic year 2018/2019. The development of workshops focused on the role of play and toys for young children’s learning promotes the participants reflection and the development of skills and knowledge to construct developmentally appropriated practices in early childhood education. Data was collected through an online questionnaire and focal groups. Results show that the PlayTrain Project contribute to the development of a body of knowledge about the role of play for early childhood education. It was possible to identify the needs of preschool teacher education and to enhance the discussion among the scientific and academic community about the importance of deepening the role of play and toys in the study plans of the masters in pre-school education.

Keywords: children's learning, early childhood education, play, teacher education, toys

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Authors: Karina Lõbus, Silver Muld, Kadri Kööp, Mare Tupits

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Aim: The aim of the research is to describe the experiences and needs of fathers’ of children with cancer in coping with the child's disease. Background: Today, about 80% of children diagnosed with malignancy in developed countries survive. Despite the positive statistics, recovery is not always certain, treatment is often very intensive and long-term. Cancer is affecting an increasing number of the population, which is increasing the demand for quality care, but the nature of expected care is currently unclear. This topic is important for the development of professional practice, as nurses complain that their knowledge to deal with the relatives of a patient with a difficult diagnosis is limited and would therefore like additional information to deal with the situation. Design: Qualitative, empirical, descriptive research. Method: The data were collected through semi-structured interviews and analysed by inductive content analysis method. Interviews were conducted during Autumn 2020. 4 subjects participated in the research. Results and Conclusions: The thesis revealed that fathers had different experiences and needs in dealing with the child's illness. Fathers' experiences of coping with child's diseases encompassed experiences with information, social relationships, healthcare, changes in personal health and experiences regarding the child. Regarding information, the respondents pointed out bad experiences with the availability of information and the ability to convey the necessary information. Experiences regarding social relationships included experiences with relatives and strangers. Regarding healthcare, fathers mentioned experiences related to the child's health and healthcare professionals. In regards to personal health, fathers pointed out negative changes in their mental and physical health. In relation to the child, the subjects revealed experiences regarding changed values, way of life and raising the child. According to the research, fathers’ needs in relation to dealing with child's cancer included material, social, and spiritual needs. In regard to material needs, fathers pointed out the need for state assistance and the needs related to the surrounding environment. The needs concerning social belonging involved needs for a driving force and involvement in the treatment process. Regarding spiritual needs, fathers expressed mixed feelings towards the need for outside and professional help.

Keywords: father, coping, cancer, child, experience, need

Procedia PDF Downloads 132

Authors: L. Guevara, Glória L. S., Corea E. E, A. Ramírez-Zamora M., Salinas-Martinez J. A., Angeles-Hernandez J. C.

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Mathematical models are useful for identifying the characteristics of sheep lactation curves to develop and implement improved strategies. However, the accuracy of these models is influenced by factors such as the recording regime, mainly the intervals between test day records (TDR). The current study aimed to evaluate the effect of different TDR intervals on the goodness of fit of the Wood model (WM) applied to dairy sheep lactations. A total of 4,494 weekly TDRs from 156 lactations of dairy crossbred sheep were analyzed. Three new databases were generated from the original weekly TDR data (7D), comprising intervals of 14(14D), 21(21D), and 28(28D) days. The parameters of WM were estimated using the “minpack.lm” package in the R software. The shape of the lactation curve (typical and atypical) was defined based on the WM parameters. The goodness of fit was evaluated using the mean square of prediction error (MSPE), Root of MSPE (RMSPE), Akaike´s Information Criterion (AIC), Bayesian´s Information Criterion (BIC), and the coefficient of correlation (r) between the actual and estimated total milk yield (TMY). WM showed an adequate estimate of TMY regardless of the TDR interval (P=0.21) and shape of the lactation curve (P=0.42). However, we found higher values of r for typical curves compared to atypical curves (0.9vs.0.74), with the highest values for the 28D interval (r=0.95). In the same way, we observed an overestimated peak yield (0.92vs.6.6 l) and underestimated time of peak yield (21.5vs.1.46) in atypical curves. The best values of RMSPE were observed for the 28D interval in both lactation curve shapes. The significant lowest values of AIC (P=0.001) and BIC (P=0.001) were shown by the 7D interval for typical and atypical curves. These results represent the first approach to define the adequate interval to record the regime of dairy sheep in Latin America and showed a better fitting for the Wood model using a 7D interval. However, it is possible to obtain good estimates of TMY using a 28D interval, which reduces the sampling frequency and would save additional costs to dairy sheep producers.

Keywords: gamma incomplete, ewes, shape curves, modeling

Procedia PDF Downloads 73

Authors: Hugo Espinosa-Andrews

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Introduction: Yogurt is widely accepted worldwide due to its high nutritional value, consistency, and texture. Their rheological properties play a significant role in consumer acceptance and are related to the manufacturing process and formulation. Typically, the viscoelastic characteristics of yogurts are studied using the small amplitude oscillatory shear test; however, the initial stages of flow and oral processing are described in the nonlinear zone, in which a large amplitude oscillatory stress test is applied. The objective of this work was to analyze the nonlinear viscoelastic behavior of commercial yogurts using Lissajous curves. Methods: Two commercial yogurts were purchased in a local store in Guadalajara Jalisco Mexico: a natural Greek-style yogurt and a low-fat traditional yogurt. Viscoelastic properties were evaluated using a large amplitude oscillatory stress procedure (LAOS). A crosshatch geometry of 40 mm and a truncation of 1000 µm were used. Stress sweeps were performed at 6.28 rad/s from 1 to 250 Pa at 5°C. The nonlinear viscoelastic properties were analyzed using the Lissajous curves. Results: The yogurts showed strain-viscoelastic behavior related to deformation-dependent materials. In the low-strain region, the elastic modulus predominated over the viscous modulus, showing gel-elastic properties. The sol-gel transitions were observed at approximately 66.5 Pa for the Greek yogurt, double that detected for traditional yogurt. The viscoelastic behavior of the yogurts was characteristic of weak excess deformation: behavior indicating a stable molecular structure at rest, and moderate structure at medium shear-forces. The normalized Lissajous curves characterized viscoelastic transitions of the yogurt as the stress increased. Greater viscoelasticity deformation was observed in Greek yogurt than in traditional yogurt, which is related to the presence of a protein network with a greater degree of crosslinking. Conclusions: The yogurt composition influences the viscoelastic properties of the material. Yogurt with the higher percentage of protein has greater viscoelastic and viscous properties, which describe a product of greater consistency and creaminess.

Keywords: yogurt, viscoelastic properties, LAOS, elastic modulus

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Authors: Akram Farhadi, Mahshid Froughan, Farahnaz Mohammadi, Maryam Rassouli, Maryam Noroozian, Leila Sadeghmoghaddam

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Background: The caregivers’ assessment of their own caregiving is considered the most important concept in exploring their experiences and has a major role in care outcomes. The rising number of people with dementia and their need for care makes family caregiving really important matter to consider and evaluate. Objectives: This study was conducted with the aim to naturalize and validate the Persian version of the Revised Caregiving Appraisal Scale (RCAS) in family caregivers of older adults with dementia. Patients and Method: In this cross-sectional methodological study, the Revised Caregiving Appraisal Scale (RCAS) was translated using International Quality of Life Assessment (IQOLA) protocol, and then a panel of experts examined its face and content validities. To ensure construct validity, the translated Revised Caregiving Appraisal Scale (RCAS) was completed by 236 family caregivers, and factor construct of the scale was assessed with 5 initial factors using confirmatory factor analysis. Internal consistency was found using Cronbach's alpha, and test-retest using intraclass correlation coefficient. Confirmatory factor analysis was performed in LISREL-8.8 software in Windows®. Results: Participating caregivers' mean age was 53.5±13.13 years. Content and face validities of the scale were confirmed according to the views expressed by family caregivers and panel of experts. The confirmatory factor analysis (CFA) results showed appropriate values for all fitness indices (RMSEA=0.046, df/X2=2.428, CFI=0.98, AGFI=0.84, GFI=0.9), and the 5-factor model was confirmed with 27 items. Overall Cronbach's alpha was reported 0.894, and test retest showed overall ICC=0.94. Conclusion: The Persian version of RCAS is a valid and reliable tool for family caregivers' assessment of their caregiving of older adults with dementia, and can be useful in assessing family caregiving interventions.

Keywords: psychometric, family caregivers, reliability and validity, elderly, dementia, self-appraisal

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Authors: Ndagi Salihu

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Corporate governance mechanisms are the control measures for ensuring that all the interests groups are equally represented and management are working towards wealth creation in the interest of all. Therefore, there are many empirical studies during the last three decades on corporate governance and firm performance. However, little is known about the effects of family ownership on the relationship between corporate governance and firm performance, especially in the developing economy like Nigeria. This limit our understanding of the unique governance dynamics of family ownership with regards firm performance. This study examined the impact of family ownership on the relationship between governance mechanisms and financial performance of publicly listed companies in Nigeria. The study adopted quantitative research methodology using correlational ex-post factor design and secondary data from annual reports and accounts of a sample of 23 listed companies for a period of 5 years (2014-2018). The explanatory variables are the board size, board composition, board financial expertise, and board audit committee attributes. Financial performance is proxy by Return on Assets (ROA) and Return on Equity (ROE). Multiple panel regression technique of data analysis was employed in the analysis, and the study found that family ownership has a significant positive effect on the relationships between corporate governance mechanisms and financial performance of publicly listed firms in Nigeria. This finding is the same for both the ROA and ROE. However, the findings indicate that board size, board financial expertise, and board audit committee attributes have a significant positive impact on the ROA and ROE of the sample firms after the moderation. Moreover, board composition has significant positive effect on financial performance of the sample listed firms in terms of ROA and ROE. The study concludes that the use of family ownership in the control of firms in Nigeria could improve performance by reducing the opportunistic actions managers as well as agency problems. The study recommends that publicly listed companies in Nigeria should allow significant family ownership of equities and participation in management.

Keywords: profitability, board characteristics, agency theory, stakeholders

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Authors: Gwo-Hwa Wan, Tai-Ho Hung, Fen-Fang Chung, Wan-Ying Lee, Hui-Ching Yang

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Air pollutant exposure results in elevated concentrations of oxidative stress and inflammatory biomarkers in general populations. Increased concentrations of inflammatory biomarkers in pregnant women would be associated with preterm labor and low birth weight. To our best knowledge, the associations between air pollutants exposure and inflammation in pregnant women and fetuses are unknown, as well as their effects on fetal growth. This study aimed to evaluate the influences of outdoor air pollutants in northern Taiwan areas on the inflammatory biomarker (high sensitivity C-reactive protein, hs-CRP) concentration in the blood of healthy pregnant women and how the biomarker impacts fetal growth. In this study, 38 healthy pregnant women who are in their first trimester and live in northern Taiwan area were recruited from the Taipei Chang Gung Memorial Hospital. Personal characteristics and prenatal examination data (e.g., blood pressure) were obtained from recruited subjects. The concentrations of inflammatory mediators, hs-CRP, in the blood of healthy pregnant women were analyzed. Additionally, hourly data of air pollutants (PM10, SO2, NO2, O3, CO) concentrations were obtained from air quality monitoring stations in Taipei area, established by the Taiwan Environmental Protection Administration. The definition of lag 0 and lag 01 are the exposure to air pollutants on the day of blood withdrawal, and the average exposure to air pollutants one day before and on the day of blood withdrawal, respectively. The statistical analyses were conducted using SPSS software version 22.0 (SPSS, Inc., Chicago, IL, USA). This analytical result indicates that the healthy pregnant women aged between 28 and 42 years old. The body mass index before pregnancy averaged 21.51 (sd = 2.51) kg/m2. Around 90% of the pregnant women had never smoking habit, and 28.95% of them had allergic diseases. Approximately around 84% and 5.26% of the pregnant women worked at indoor and outdoor environments, respectively. The mean hematocrit level of the pregnant women was 37.10%, and the hemoglobin levels were ranged between 10.1 and 14.7 g/dL with 12.47 g/dL of mean value. The blood hs-CRP concentrations of healthy pregnant women in the first trimester ranged between 0.32 and 32.5 mg/L with 2.83 (sd = 5.69) mg/L of mean value. The blood hs-CRP concentrations were positively associated with ozone concentrations at lag 0-14 (r = 0.481, p = 0.017) in healthy pregnant women. Significant lag effects were identified in ozone at lag 0-14 with a positive excess concentration of blood hs-CRP.

Keywords: air pollutant, hs-CRP, pregnant woman, ozone, first trimester

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Authors: Mike Chia-Yu Huang

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China’s port facility construction projects in the Indian Ocean (IO) region, Gwadar Port and Djibouti Port projects in particular, have led to a heated debate among both Chinese and Western strategists over whether the country has literally been carrying out its “string of pearls” strategy, an alleged Chinese plan to challenge America’s military predominance in South Asia. Even though the Chinese government repeatedly denied the existence of such a strategy and highlighted the civilian/commercial nature of its port projects, it has significantly enhanced its strategic cooperation with littoral countries in the IO region since the “One Belt One Road” initiative was introduced by Chinese President Xi Jinping in 2013. Whether China does have a plan to expand its sphere of military influence westward concerns the balance of power in the IO region. If the answer is positive, the security environment there will be changed drastically. This paper argues that rather than simply copying the U.S. model of developing overseas military bases along the IO periphery, Beijing has been deliberating a more sophisticated plan for its physical presence there: creating a new set of “overseas strategic pivots.” These “pivots,” semi-military and semi-commercial in nature, are designed to help Beijing sustain its anti-piracy operations in the Gulf of Aden and serve as forward stations for the transportation of China’s imported energy and merchandise. They can support the Chinese Navy’s operations overseas but are not supposed to undertake face-to-face combat missions. This upgraded Chinese scheme can be identified as “string of pearls” strategy 2.0. Moreover, it is expected to help China deepen its roots in the IO region, implying that Beijing has to a large extent scratched its old diplomatic philosophy which highlighted the merits of non-interference and nonalignment. While a full-scale maritime confrontation between China and the U.S.-India security alliance is unlikely to be witnessed in the near future, an ambitious Chinese plan to step into the global maritime domain has been evidently shown.

Keywords: Chinese navy, Djibouti, Gwadar, Indian Ocean, string of pearls strategy

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Authors: Shuaili Ji

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The correct use of verbs is an important element of high-quality research articles, and thus for Chinese EFL learners, it is significant to master characteristics of verbs and to precisely use verbs. However, some researches have shown that there are differences in using verbs between learners and native speakers and learners have difficulty in using English verbs. This corpus-based quantitative research can enhance learners’ knowledge of English verbs and promote the quality of research article abstracts even of the whole academic writing. The aim of this study is to find the differences between learners’ and native speakers’ use of verbs and to study the factors that contribute to those differences. To this end, the research question is as follows: What are the differences between most frequently used verbs by learners and those by native speakers? The research question is answered through a study that uses corpus-based data-driven approach to analyze the verbs used by learners in their abstract writings in terms of collocation, colligation and semantic prosody. The results show that: (1) EFL learners obviously overused ‘be, can, find, make’ and underused ‘investigate, examine, may’. As to modal verbs, learners obviously overused ‘can’ while underused ‘may’. (2) Learners obviously overused ‘we find + object clauses’ while underused ‘nouns (results, findings, data) + suggest/indicate/reveal + object clauses’ when expressing research results. (3) Learners tended to transfer the collocation, colligation and semantic prosody of shǐ and zuò to make. (4) Learners obviously overused ‘BE+V-ed’ and used BE as the main verb. They also obviously overused the basic forms of BE such as be, is, are, while obviously underused its inflections (was, were). These results manifested learners’ lack of accuracy and idiomatic property in verb usage. Due to the influence of the concept transfer of Chinese, the verbs in learners’ abstracts showed obvious transfer of mother language. In addition, learners have not fully mastered the use of verbs, avoiding using complex colligations to prevent errors. Based on these findings, the present study has implications for English teaching, seeking to have implications for English academic abstract writing in China. Further research could be undertaken to study the use of verbs in the whole dissertation to find out whether the characteristic of the verbs in abstracts can apply in the whole dissertation or not.

Keywords: academic writing abstracts, Chinese EFL learners, corpus-based, data-driven, verbs

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Authors: Maciej Sobczak, Julita Pietrzak, Tomasz Płoszaj, Agnieszka Robaszkiewicz

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Brg1, a member of SWI/SNF complex, plays a role in chromatin remodeling, therefore, regulates expression of many genes. Brg1 is an ATPase of SWI/SNF complex, thus its activity requires ATP. Through its bromodomain recognizes acetylated histone residues and evicts them, thus promoting transcriptionally active state of chromatin. One of the enzymes that is responsible for acetylation of histone residues is Ep300. It was previously shown in the literature that cooperation of Brg1 and Ep300 occurs at the promoter regions that have binding sites for E2F-family transcription factors as well as CpG islands. According to literature, approximately 20% of human cancer possess mutation in Brg1 or any other crucial SWI/SNF subunit. That phenomenon makes Brg1-Ep300 a very promising target for anti-cancer therapy. Therefore in our study, we investigated if physical interaction between Brg1 and Ep300 exists and what impact those two proteins have on key for breast cancer cells processes such as DNA damage repair and cell proliferation. Bioinformatical analysis pointed out, that genes involved in cell proliferation and DNA damage repair are overexpressed in MCF7 and MDA-MB-231 cells. Moreover, promoter regions of these genes are highly acetylated, which suggests high transcriptional activity of those sites. Notably, many of those gene possess within their promoters an E2F, Brg1 motives, as well as CpG islands and acetylated histones. Our data show that Brg1 physically interacts with Ep300, and together they regulate expression of genes involved in DNA damage repair and cell proliferation. Upon inhibiting Brg1 or Ep300, expression of vital for cancer cell survival genes such as CDK2/4, BRCA1/2, PCNA, and XRCC1 is decreased in MDA-MB-231 and MCF7 cells. Moreover, inhibition or silencing of either Brg1 or Ep300 leads to cell cycle arrest in G1. After inhibition of BRG1 or Ep300 on tested gene promoters, the repressor complex including Rb, HDAC1, and EZH2 is formed, which inhibits gene expression. These results highlight potentially significant target for targeted anticancer therapy to be introduced as a supportive therapy.

Keywords: brg1, ep300, breast cancer, epigenetics

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Authors: Kausar Harun, Ahmad Azmin Mohamad

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Zinc oxide (ZnO) has been extensively used in optoelectronic devices, with recent interest as photoanode material in dye-sensitize solar cell. Numerous methods employed to experimentally synthesized ZnO, while some are theoretically-modeled. Both approaches provide information on ZnO properties, but theoretical calculation proved to be more accurate and timely effective. Thus, integration between these two methods is essential to intimately resemble the properties of synthesized ZnO. In this study, experimentally-grown ZnO nanoparticles were prepared by sol-gel storage method with zinc acetate dihydrate and methanol as precursor and solvent. A 1 M sodium hydroxide (NaOH) solution was used as stabilizer. The optimum time to produce ZnO nanoparticles were recorded as 12 hours. Phase and structural analysis showed that single phase ZnO produced with wurtzite hexagonal structure. Further work on quantitative analysis was done via Rietveld-refinement method to obtain structural and crystallite parameter such as lattice dimensions, space group, and atomic coordination. The lattice dimensions were a=b=3.2498Å and c=5.2068Å which were later used as main input in first-principles calculations. By applying density-functional theory (DFT) embedded in CASTEP computer code, the structure of synthesized ZnO was built and optimized using several exchange-correlation functionals. The generalized-gradient approximation functional with Perdew-Burke-Ernzerhof and Hubbard U corrections (GGA-PBE+U) showed the structure with lowest energy and lattice deviations. In this study, emphasize also given to the modification of valence electron energy level to overcome the underestimation in DFT calculation. Both Zn and O valance energy were fixed at Ud=8.3 eV and Up=7.3 eV, respectively. Hence, the following electronic and optical properties of synthesized ZnO were calculated based on GGA-PBE+U functional within ultrasoft-pseudopotential method. In conclusion, the incorporation of Rietveld analysis into first-principles calculation was valid as the resulting properties were comparable with those reported in literature. The time taken to evaluate certain properties via physical testing was then eliminated as the simulation could be done through computational method.

Keywords: density functional theory, first-principles, Rietveld-refinement, ZnO nanoparticles

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Authors: Hoang Thi Quynh, Shima Kazuto

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Organic farming is gaining interest in Vietnam. However, organic fertilizer production is not sufficiently regulated, resulting in unknown quality. This study investigated characteristics of so-called organic fertilizers in the Vietnam’s market and their mineralization in soil-plant system. We collected 15 commercial products (11 domestic and 4 imported) which labelled 'organic fertilizer' in the market to analyze nutrients composition. A 20 day-incubation experiment was carried on with 80 g sandy-textured soil, amended with the fertilizer at a rate of 109.4 mgN.kg⁻¹soil in 150 mL glass bottle at 25℃. We categorized them according to nutrients content and mineralization rate, and then selected 8 samples for cultivation experiment. The experiment was conducted by growing Komatsuna (Brassica campestris) in sandy-textured soil using an automatic watering apparatus in a greenhouse. The fertilizers were applied to the top one-third of the soil stratum at a rate of 200 mgN.kg⁻¹ soil. Our study also analyzed material flow of coffee husk compost in Central Highland of Vietnam. Total N, P, K, Ca, Mg and C: N ratio varied greatly cross the domestic products, whereas they were quite similar among the imported materials. The proportion of inorganic-N to T-N of domestic products was higher than 25% in 8 of 11 samples. These indicate that N concentration increased dramatically in most domestic products compared with their raw materials. Additionally, most domestic products contained less P, and their proportions of Truog-P to T-P were greatly different. These imply that some manufactures were interested in adjusting P concentration, but some ones were not. Furthermore, the compost was made by mixing with chemical substances to increase nutrients content (N, P), and also added construction surplus soil to gain weight before packing product to sell in the market as 'organic fertilizer'. There was a negative correlation between C:N ratio and mineralization rate of the fertilizers. There was a significant difference in N efficiency among the fertilizer treatments. N efficiency of most domestic products was higher than chemical fertilizer and imported organic fertilizers. These results suggest regulations on organic fertilizers production needed to support organic farming that is based on internationally accepted standards in Vietnam.

Keywords: inorganic N, mineralization, N efficiency, so-called organic fertilizers, Vietnam’s market

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Authors: Nur Aimi Syairah Mohd Abdul Alim, Azilah Ajit, A. Z. Sulaiman

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The present study aimed to investigate the effects of ultrasound-assisted extraction (UAE) on the extraction of Vitexin and Iso-Vitexin from Ficus deltoidea plants. In recent years, ultrasound technology has been found to be a potential herbal extraction technique. The passage of ultrasound energy in a liquid medium generates mechanical agitation and other physical effects due to acoustic cavitation. The main goal is to optimised ultrasonic-assisted extraction condition providing the highest extraction yield with the most desirable antioxidant activity and stability. Thus, a series of experiments has been developed to investigate the effect of ultrasound energy on the vegetal material and the implemented parameters by using HPLC-photodiode array detection. The influences of several experimental parameters on the ultrasonic extraction of Ficus deltoidea leaves were investigated: extraction time (1-8 h), solvent-to-water ratio (1:10 to 1:50), temperature (50–100 °C), duty cycle (10–continuous sonication) and intensity. The extracts at the optimized condition were compared with those obtained by conventional boiling extraction, in terms of bioactive constituents yield and chemical composition. The compounds of interest identified in the extracts were Vitexin and Isovitexin, which possess anti-diabetic, anti-oxidant and anti-cancer properties. Results showed that the main variables affecting the extraction process were temperature and time. Though in less extent, solvent-to-water ratio, duty cycle and intensity are also demonstrated to be important parameters. The experimental values under optimal conditions were in good consistent with the predicted values, which suggested that ultrasonic-assisted extraction (UAE) is more efficient process as compared to conventional boiling extraction. It recommended that ultrasound extraction of Ficus deltoidea plants are feasible to replace the traditional time-consuming and low efficiency preparation procedure in the future modernized and commercialized manufacture of this highly valuable herbal medicine.

Keywords: Ficus, ultrasounds, vitexin, isovitexin

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Authors: Shishay Kidanu, Abdullah Alhaj

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Sinkholes in the karst terrain of Greene County, Missouri, pose significant geohazards, imposing challenges on construction and infrastructure development, with potential threats to lives and property. To address these issues, understanding the influencing factors and modeling sinkhole susceptibility is crucial for effective mitigation through strategic changes in land use planning and practices. This study utilizes geographic information system (GIS) software to collect and process diverse data, including topographic, geologic, hydrogeologic, and anthropogenic information. Nine key sinkhole influencing factors, ranging from slope characteristics to proximity to geological structures, were carefully analyzed. The Frequency Ratio method establishes relationships between attribute classes of these factors and sinkhole events, deriving class weights to indicate their relative importance. Weighted integration of these factors is accomplished using the Analytic Hierarchy Process (AHP) and the Weighted Linear Combination (WLC) method in a GIS environment, resulting in a comprehensive sinkhole susceptibility index (SSI) model for the study area. Employing Jenk's natural break classifier method, the SSI values are categorized into five distinct sinkhole susceptibility zones: very low, low, moderate, high, and very high. Validation of the model, conducted through the Area Under Curve (AUC) and Sinkhole Density Index (SDI) methods, demonstrates a robust correlation with sinkhole inventory data. The prediction rate curve yields an AUC value of 74%, indicating a 74% validation accuracy. The SDI result further supports the success of the sinkhole susceptibility model. This model offers reliable predictions for the future distribution of sinkholes, providing valuable insights for planners and engineers in the formulation of development plans and land-use strategies. Its application extends to enhancing preparedness and minimizing the impact of sinkhole-related geohazards on both infrastructure and the community.

Keywords: sinkhole, GIS, analytical hierarchy process, frequency ratio, susceptibility, Missouri

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Authors: Masoumeh Ghorbania, Falk Liebnerb, Hendrikus W.G. van Herwijnenc, Johannes Konnertha

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Phenol formaldehyde (PF) resins are widely used as wood adhesives for variety of industrial products such as plywood, laminated veneer lumber and others. Lignin as a main constituent of wood has become well-known as a potential substitute for phenol in PF adhesives because of their structural similarity. During the last decades numerous research approaches have been carried out to substitute phenol with pulping-derived lignin, whereby the lower reactivity of resins synthesized with shares of lignin seem to be one of the major challenges. This work reports about a systematic screening of different types of lignin (plant origin and pulping process) for their suitability to replace phenol in phenolic resins. Lignin from different plant sources (softwood, hardwood and grass) were used, as these should differ significantly in their reactivity towards formaldehyde of their reactive phenolic core units. Additionally a possible influence of the pulping process was addressed by using the different types of lignin from soda, kraft, and organosolv process and various lignosulfonates (sodium, ammonium, calcium, magnesium). To determine the influence of lignin on the adhesive performance beside others the rate of viscosity development, bond strength development of varying hot pressing time and other thermal properties were investigated. To evaluate the performance of the cured end product, a few selected properties were studied at the example of solid wood-adhesive bond joints, compact panels and plywood. As main results it was found that lignin significantly accelerates the viscosity development in adhesive synthesis. Bonding strength development during curing of adhesives decelerated for all lignin types, while this trend was least for pine kraft lignin and spruce sodium lignosulfonate. However, the overall performance of the products prepared with the latter adhesives was able to fulfill main standard requirements, even after exposing the products to harsh environmental conditions. Thus, a potential application can be considered for processes where reactivity is less critical but adhesive cost and product performance is essential.

Keywords: phenol formaldehyde resin, lignin phenol formaldehyde resin, ABES, DSC

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