Search results for: density functional theoretical
Commenced in January 2007
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Edition: International
Paper Count: 9323

Search results for: density functional theoretical

2633 Theoretical Investigations and Simulation of Electromagnetic Ion Cyclotron Waves in the Earth’s Magnetosphere Through Magnetospheric Multiscale Mission

Authors: A. A. Abid

Abstract:

Wave-particle interactions are considered to be the paramount in the transmission of energy in collisionless space plasmas, where electromagnetic fields confined the charged particles movement. One of the distinct features of energy transfer in collisionless plasma is wave-particle interaction which is ubiquitous in space plasmas. The three essential populations of the inner magnetosphere are cold plasmaspheric plasmas, ring-currents, and radiation belts high energy particles. The transition region amid such populations initiates wave-particle interactions among distinct plasmas and the wave mode perceived in the magnetosphere is the electromagnetic ion cyclotron (EMIC) wave. These waves can interact with numerous particle species resonantly, accompanied by plasma particle heating is still in debate. In this work we paid particular attention to how EMIC waves impact plasma species, specifically how they affect the heating of electrons and ions during storm and substorm in the Magnetosphere. Using Magnetospheric Multiscale (MMS) mission and electromagnetic hybrid simulation, this project will investigate the energy transfer mechanism (e.g., Landau interactions, bounce resonance interaction, cyclotron resonance interaction, etc.) between EMIC waves and cold-warm plasma populations. Other features such as the production of EMIC waves and the importance of cold plasma particles in EMIC wave-particle interactions will also be worth exploring. Wave particle interactions, electromagnetic hybrid simulation, electromagnetic ion cyclotron (EMIC) waves, Magnetospheric Multiscale (MMS) mission, space plasmas, inner magnetosphere

Keywords: MMS, magnetosphere, wave particle interraction, non-maxwellian distribution

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2632 The Subcellular Localisation of EhRRP6 and Its Involvement in Pre-Ribosomal RNA Processing in Growth-Stressed Entamoeba histolytica

Authors: S. S. Singh, A. Bhattacharya, S. Bhattacharya

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The eukaryotic exosome complex plays a pivotal role in RNA biogenesis, maturation, surveillance and differential expression of various RNAs in response to varying environmental signals. The exosome is composed of evolutionary conserved nine core subunits and the associated exonucleases Rrp6 and Rrp44. Rrp6p is crucial for the processing of rRNAs, other non-coding RNAs, regulation of polyA tail length and termination of transcription. Rrp6p, a 3’-5’ exonuclease is required for degradation of 5’-external transcribed spacer (ETS) released from the rRNA precursors during the early steps of pre-rRNA processing. In the parasitic protist Entamoeba histolytica in response to growth stress, there occurs the accumulation of unprocessed pre-rRNA and 5’ ETS sub fragment. To understand the processes leading to this accumulation, we looked for Rrp6 and the exosome subunits in E. histolytica, by in silico approaches. Of the nine core exosomal subunits, seven had high percentage of sequence similarity with the yeast and human. The EhRrp6 homolog contained exoribonuclease and HRDC domains like yeast but its N- terminus lacked the PMC2NT domain. EhRrp6 complemented the temperature sensitive phenotype of yeast rrp6Δ cells suggesting conservation of biological activity. We showed 3’-5’ exoribonuclease activity of EhRrp6p with in vitro-synthesized appropriate RNAs substrates. Like the yeast enzyme, EhRrp6p degraded unstructured RNA, but could degrade the stem-loops slowly. Furthermore, immunolocalization revealed that EhRrp6 was nuclear-localized in normal cells but was diminished from nucleus during serum starvation, which could explain the accumulation of 5’ETS during stress. Our study shows functional conservation of EhRrp6p in E.histolytica, an early-branching eukaryote, and will help to understand the evolution of exosomal components and their regulatory function.

Keywords: entamoeba histolytica, exosome complex, rRNA processing, Rrp6

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2631 Quantitative Proteome Analysis and Bioactivity Testing of New Zealand Honeybee Venom

Authors: Maryam Ghamsari, Mitchell Nye-Wood, Kelvin Wang, Angela Juhasz, Michelle Colgrave, Don Otter, Jun Lu, Nazimah Hamid, Thao T. Le

Abstract:

Bee venom, a complex mixture of peptides, proteins, enzymes, and other bioactive compounds, has been widely studied for its therapeutic application. This study investigated the proteins present in New Zealand (NZ) honeybee venom (BV) using bottom-up proteomics. Two sample digestion techniques, in-solution digestion and filter-aided sample preparation (FASP), were employed to obtain the optimal method for protein digestion. Sequential Window Acquisition of All Theoretical Mass Spectra (SWATH–MS) analysis was conducted to quantify the protein compositions of NZ BV and investigate variations in collection years. Our results revealed high protein content (158.12 µg/mL), with the FASP method yielding a larger number of identified proteins (125) than in-solution digestion (95). SWATH–MS indicated melittin and phospholipase A2 as the most abundant proteins. Significant variations in protein compositions across samples from different years (2018, 2019, 2021) were observed, with implications for venom's bioactivity. In vitro testing demonstrated immunomodulatory and antioxidant activities, with a viable range for cell growth established at 1.5-5 µg/mL. The study underscores the value of proteomic tools in characterizing bioactive compounds in bee venom, paving the way for deeper exploration into their therapeutic potentials. Further research is needed to fractionate the venom and elucidate the mechanisms of action for the identified bioactive components.

Keywords: honeybee venom, proteomics, bioactivity, fractionation, swath-ms, melittin, phospholipase a2, new zealand, immunomodulatory, antioxidant

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2630 Prevention of Corruption in Public Purchases

Authors: Anatoly Krivinsh

Abstract:

The results of dissertation research "Preventing and combating corruption in public procurement" are presented in this publication. The study was conducted 2011 till 2013 in a Member State of the European Union, in the Republic of Latvia. Goal of the thesis is to explore corruption prevention and combating issues in public procurement sphere, to identify the prevalence rates, determinants and contributing factors and prevention opportunities in Latvia. In the first chapter the author analyses theoretical aspects of understanding corruption in public procurement, with particular emphasis on corruption definition problem, its nature, causes and consequences. A separate section is dedicated to the public procurement concept, mechanism and legal framework. In the first part of this work the author presents cognitive methodology of corruption in public procurement field, based on which the author has carried out an analysis of corruption situation in public procurement in Republic of Latvia. In the second chapter of the thesis, the author analyzes the problem of corruption in public procurement, including its historical aspects, typology and classification of corruption subjects involved, corruption risk elements in public procurement and their identification. During the development of the second chapter author's practical experience in public procurements was widely used. The third and fourth chapter deals with issues related to the prevention and combating corruption in public procurement, namely the operation of the concept, principles, methods and techniques, subjects in Republic of Latvia, as well as an analysis of foreign experience in preventing and combating corruption. The fifth chapter is devoted to the corruption prevention and combating perspectives and their assessment. In this chapter the author has made the evaluation of corruption prevention and combating measures efficiency in Republic of Latvia, assessment of anti-corruption legislation development stage in public procurement field in Latvia.

Keywords: prevention of corruption, public purchases, good governance, human rights

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2629 CFD Study of Subcooled Boiling Flow at Elevated Pressure Using a Mechanistic Wall Heat Partitioning Model

Authors: Machimontorn Promtong, Sherman C. P. Cheung, Guan H. Yeoh, Sara Vahaji, Jiyuan Tu

Abstract:

The wide range of industrial applications involved with boiling flows promotes the necessity of establishing fundamental knowledge in boiling flow phenomena. For this purpose, a number of experimental and numerical researches have been performed to elucidate the underlying physics of this flow. In this paper, the improved wall boiling models, implemented on ANSYS CFX 14.5, were introduced to study subcooled boiling flow at elevated pressure. At the heated wall boundary, the Fractal model, Force balance approach and Mechanistic frequency model are given for predicting the nucleation site density, bubble departure diameter, and bubble departure frequency. The presented wall heat flux partitioning closures were modified to consider the influence of bubble sliding along the wall before the lift-off, which usually happens in the flow boiling. The simulation was performed based on the Two-fluid model, where the standard k-ω SST model was selected for turbulence modelling. Existing experimental data at around 5 bars were chosen to evaluate the accuracy of the presented mechanistic approach. The void fraction and Interfacial Area Concentration (IAC) are in good agreement with the experimental data. However, the predicted bubble velocity and Sauter Mean Diameter (SMD) are over-predicted. This over-prediction may be caused by consideration of only dispersed and spherical bubbles in the simulations. In the future work, the important physical mechanisms of bubbles, such as merging and shrinking during sliding on the heated wall will be incorporated into this mechanistic model to enhance its capability for a wider range of flow prediction.

Keywords: subcooled boiling flow, computational fluid dynamics (CFD), mechanistic approach, two-fluid model

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2628 Potential of Rice Husk Ash as a Partial Cement Replacement in Concrete for Highways Application

Authors: Ash Ahmed, Fraser Hyndman, Heni Fitriani, John Kamau

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The highway pavement is the biggest structural asset a government can construct and maintain. Concrete rigid pavements are used to carry traffic in large volumes across countries safely and efficiently. Pavement quality concrete mixes have high levels of cement which contribute to up to 10% of global CO₂ emissions. Currently the UK specifies (ground granulated blastfurnace slag) GGBS and (pulverised fuel ash) PFA to reduce the quantity of cement used in pavement construction. GGBS and PFA come from heavy industry that should not be relied upon to improve the sustainability of construction materials. This report shows that cement in pavement quality concrete can be replaced with rice husk ash (RHA) without causing adverse effects to the mechanical properties required for highways. RHA comes from the food production industry and is vital for the growing global population. It is thus a socially responsible objective to use a pozzolan in highway pavement construction that is sourced from an environmentally friendly industry. The report investigates the properties of RHA mixes and compares them to existing pavement quality mixes already used and specified. The report found that sieving RHA and not grinding it gives the best performance. Due to the low density of RHA the investigation found that replacing cement by volume rather than weight provided the best results. Findings showed that CEM II mixed with 20% RHA meets the required specification for pavement quality concrete and mitigates using the comparative CEM I. The investigation also notes that RHA is observed to be more reactive with CEM II rather than CEM I and suits early strength gains required for pavement construction. The report concludes that RHA is a sustainable material that reduces the embodied CO₂ of pavement quality concrete, which is well suited for UK highway specifications and has the potential to improve the lives of people living in the developing countries.

Keywords: pavement, pozzolan, rice husk ash, sustainable concrete

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2627 The Counselling Practice of School Social Workers in Swedish Elementary Schools - A Focus Group Study

Authors: Kjellgren Maria, Lilliehorn Sara, Markström Urban

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This article describes the counselling practice of school social workers (SSWs) with individual children. SSWs work in the school system’s pupil health team, whose primary task is health promotion and prevention. The work of SSWs is about helping children and adolescents who, for various reasons, suffer from mental ill-health, school absenteeism, or stress that make them unable to achieve their intended goals. SSWs preferably meet these children in individual counselling sessions. The aim of this article is to describe and analyse SSWs’ experience of counselling with children and to examine the characteristics of counselling practice. The data collection was conducted through four semi-structured focus group interviews with a total of 22 SSWs in four different regions in Sweden. SSWs provide counselling to children in order to bring about improved feelings or behavioural changes. It can be noted that SSWs put emphasis on both the counselling process and the alliance with the child. The interviews showed a common practice among SSWs regarding the structure of the counselling sessions, with certain steps and approaches being employed. However, the specific interventions differed and were characterised by an eclectic standpoint in which SSWs utilise a broad repertoire of therapeutic schools and techniques. Furthermore, a relational perspective emerged as a most prominent focus for the SSWs by re-emerging throughout the material. We believe that SSWs could benefit from theoretical perspectives on ‘contextual model’ and ‘attachment theory’ as ‘models of the mind’. Being emotionally close to the child and being able to follow their development requires a lot from SSWs, as both professional caregivers and as “safe havens”.

Keywords: school social conselling, school social workers, contextual model, attachment thory

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2626 In vitro Evaluation of Prebiotic Potential of Wheat Germ

Authors: Lígia Pimentel, Miguel Pereira, Manuela Pintado

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Wheat germ is a by-product of wheat flour refining. Despite this by-product being a source of proteins, lipids, fibres and complex carbohydrates, and consequently a valuable ingredient to be used in Food Industry, only few applications have been studied. The main goal of this study was to assess the potential prebiotic effect of natural wheat germ. The prebiotic potential was evaluated by in vitro assays with individual microbial strains (Lactobacillus paracasei L26 and Lactobacillus casei L431). A simulated model of the gastrointestinal digestion was also used including the conditions present in the mouth (artificial saliva), oesophagus–stomach (artificial gastric juice), duodenum (artificial intestinal juice) and ileum. The effect of natural wheat germ and wheat germ after digestion on the growth of lactic acid bacteria was studied by growing those microorganisms in de Man, Rogosa and Sharpe (MRS) broth (with 2% wheat germ and 1% wheat germ after digestion) and incubating at 37 ºC for 48 h with stirring. A negative control consisting of MRS broth without glucose was used and the substrate was also compared to a commercial prebiotic fructooligosaccharides (FOS). Samples were taken at 0, 3, 6, 9, 12, 24 and 48 h for bacterial cell counts (CFU/mL) and pH measurement. Results obtained showed that wheat germ has a stimulatory effect on the bacteria tested, presenting similar (or even higher) results to FOS, when comparing to the culture medium without glucose. This was demonstrated by the viable cell counts and also by the decrease on the medium pH. Both L. paracasei L26 and L. casei L431 could use these compounds as a substitute for glucose with an enhancement of growth. In conclusion, we have shown that wheat germ stimulate the growth of probiotic lactic acid bacteria. In order to understand if the composition of gut bacteria is altered and if wheat germ could be used as potential prebiotic, further studies including faecal fermentations should be carried out. Nevertheless, wheat germ seems to have potential to be a valuable compound to be used in Food Industry, mainly in the Bakery Industry.

Keywords: by-products, functional ingredients, prebiotic potential, wheat germ

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2625 Language Development and Learning about Violence

Authors: Karen V. Lee

Abstract:

The background and significance of this study involves research about a music teacher discovering how language development and learning can help her overcome harmful and lasting consequences from sexual violence. Education about intervention resources from language development that helps her cope with consequences influencing her career as teacher. Basic methodology involves the qualitative method of research as theoretical framework where the author is drawn into a deep storied reflection about political issues surrounding teachers who need to overcome social, psychological, and health risk behaviors from violence. Sub-themes involve available education from learning resources to ensure teachers receive social, emotional, physical, spiritual, and intervention resources that evoke visceral, emotional responses from the audience. Major findings share how language development and learning provide helpful resources to victims of violence. It is hoped the research dramatizes an episodic yet incomplete story that highlights the circumstances surrounding the protagonist’s life. In conclusion, the research has a reflexive storied framework that embraces harmful and lasting consequences from sexual violence. The reflexive story of the sensory experience critically seeks verisimilitude by evoking lifelike and believable feelings from others. Thus, the scholarly importance of using language development and learning for intervention resources can provide transformative aspects that contribute to social change. Overall, the circumstance surrounding the story about sexual violence is not uncommon in society. Language development and learning supports the moral mission to help teachers overcome sexual violence that socially impacts their professional lives as victims.

Keywords: intervention, language development and learning, sexual violence, story

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2624 Cultural Notion of Mental Health and Role of Local Deities: A Case Study of North-Western Himalaya

Authors: Randhir Singh Ranta

Abstract:

The attempt to achieve and maintain an optimum state of health has always drilled the human mind and consequently, a number of healing systems have evolved around the world. Communities have contrived procedures to alleviate the wearisome condition arising out of ailments, using their own system, which differ from one community to another. Each culture has evolved a viewpoint regarding the cause of disease and the same is embedded in their belief systems. In India, the elementary proposition of mental health is within the community. From the theoretical perspective, the individual obeying and adhering to the institution of village deity represents the two changeovers i.e. from biological to psychological and from psychological to spiritual. In order to understand the cultural notion of mental health and role of local deities, a study was conducted in North-western Himalaya with a purpose to study the belief system of people in context of institution of village deity and establish a relationship between religiosity and general well-being among the believers. An effort was made to compare the mental health status of people facing psychosomatic disorders with the normal. Quantitative and qualitative methods were used for the purpose. Case studies were made to have an understanding of nature of mental and behavioural disorders and the role of institutions of local deities in managing the same. The results revealed that mountain communities have firm beliefs in local deities. A significant difference was found on the scores of belief and wellbeing, and a positive correlation was found between the belief assessment and general wellbeing.

Keywords: culture notion, mental health, healing system, deities

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2623 Bioaccessible Phenolics, Phenolic Bioaccessibilities and Antioxidant Activities of Cookies Supplemented with Pumpkin Flour

Authors: Emine Aydin, Duygu Gocmen

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In this study, pumpkin flours (PFs) were used to replace wheat flour in cookie formulation at three different levels (10%, 20% and 30% w/w). For this purpose PFs produced by two different applications (with or without metabisulfite pre-treatment) and then dried in freeze dryer. Control sample included no PFs. The total phenolic contents of the cookies supplemented with PFs were higher than that of control and gradually increased in total phenolic contents of cookies with increasing PF supplementation levels. Phenolic content makes also significant contribution on nutritional excellence of the developed cookies. Pre-treatment with metabisulfite (MS) had a positive effect on free, bound and total phenolics of cookies which are supplemented with various levels of MS-PF. This is due to a protective effect of metabisulfite pretreatment for phenolic compounds in the pumpkin flour. Phenolic antioxidants may act and absorb in a different way in humans and thus their antioxidant and health effects will be changed accordingly. In the present study phenolics’ bioavailability of cookies was investigated in order to assess PF as sources of accessible phenolics. The content of bioaccessible phenolics and phenolic bioaccessibility of cookies supplemented with PFs had higher than those of control sample. Cookies enriched with 30% MS-PF had the highest bioaccessible phenolics (597.86 mg GAE 100g-1) and phenolic bioaccessibility (41.71%). MS application in PF production caused a significant increase in phenolic bioaccessibility of cookies. According to all assay (ABTS, CUPRAC, FRAP and DPPH), antioxidant activities of cookies with PFs higher than that of control cookie. It was also observed that the cookies supplemented with MS-PF had significantly higher antioxidant activities than those of cookies including PF. In presented study, antioxidative bioaccessibilities of cookies were also determined. The cookies with PFs had significantly (p ≤ 0.05) higher antioxidative bioaccessibilities than control ones. Increasing PFs levels enhanced antioxidative bioaccessibilities of cookies. As a result, PFs addition improved the nutritional and functional properties of cookie by causing increase in antioxidant activity, total phenolic content, bioaccessible phenolics and phenolic bioaccessibilities.

Keywords: phenolic compounds, antioxidant activity, dietary fiber, pumpkin, freeze drying, cookie

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2622 Mothers and Daughters’ Relationships: The Gender Dialectic in Cross Cultural Comparison

Authors: Ronit Reuven Even Zahav

Abstract:

Context: Mother-daughter relationships are crucial in shaping women's identities, yet research on these relationships during cross-cultural transitions is limited. Research aim: To explore and compare adult mother-daughter relationships among Ethiopian, Russian, and Israeli groups, focusing on gender and ethnicity. Methodology: Qualitative study with 87 participants, included 37 mother-daughter dyads, and 13 mothers, using semi-structured interviews on various themes related to the relationships. Findings: Revealed three relationship patterns among the groups, highlighting differences in sharing, expectations, and stress, with Ethiopian mothers showing distinct characteristics. Theoretical importance: Highlights the impact of intercultural transitions and societal status on mother-daughter relationships, contributing to understanding the gender dialectic. Data collection: Through semi-structured interviews that were thematically coded and analyzed for similarities and differences, providing insights into the relationships. Question addressed: Explored how mother-daughter relationships are influenced by gender, ethnicity, and cross-cultural transitions. Conclusion: Stresses the significance of comprehending the effects of intercultural transitions and social exclusion on mother-daughter relationships, emphasizing the gender dialectic and women's societal status. Cultural aspects of mother-daughter relationships such as sharing and closeness in context of gender expectations of similarity and difference in relationships emphasize the need for a gender-informed tool and contribute to the development of a gender-informed tool that can help comprehend and address inequalities and promote empowerment in mother-daughter relationships within diverse cultural groups.

Keywords: gender dialectic, diversity, mother-daughter relationships, gender informed perspectives

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2621 Fluid Structure Interaction Study between Ahead and Angled Impact of AGM 88 Missile Entering Relatively High Viscous Fluid for K-Omega Turbulence Model

Authors: Abu Afree Andalib, Rafiur Rahman, Md Mezbah Uddin

Abstract:

The main objective of this work is to anatomize on the various parameters of AGM 88 missile anatomized using FSI module in Ansys. Computational fluid dynamics is used for the study of fluid flow pattern and fluidic phenomenon such as drag, pressure force, energy dissipation and shockwave distribution in water. Using finite element analysis module of Ansys, structural parameters such as stress and stress density, localization point, deflection, force propagation is determined. Separate analysis on structural parameters is done on Abacus. State of the art coupling module is used for FSI analysis. Fine mesh is considered in every case for better result during simulation according to computational machine power. The result of the above-mentioned parameters is analyzed and compared for two phases using graphical representation. The result of Ansys and Abaqus are also showed. Computational Fluid Dynamics and Finite Element analyses and subsequently the Fluid-Structure Interaction (FSI) technique is being considered. Finite volume method and finite element method are being considered for modelling fluid flow and structural parameters analysis. Feasible boundary conditions are also utilized in the research. Significant change in the interaction and interference pattern while the impact was found. Theoretically as well as according to simulation angled condition was found with higher impact.

Keywords: FSI (Fluid Surface Interaction), impact, missile, high viscous fluid, CFD (Computational Fluid Dynamics), FEM (Finite Element Analysis), FVM (Finite Volume Method), fluid flow, fluid pattern, structural analysis, AGM-88, Ansys, Abaqus, meshing, k-omega, turbulence model

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2620 Elucidating the Genetic Determinism of Seed Protein Plasticity in Response to the Environment Using Medicago truncatula

Authors: K. Cartelier, D. Aime, V. Vernoud, J. Buitink, J. M. Prosperi, K. Gallardo, C. Le Signor

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Legumes can produce protein-rich seeds without nitrogen fertilizer through root symbiosis with nitrogen-fixing rhizobia. Rich in lysine, these proteins are used for human nutrition and animal feed. However, the instability of seed protein yield and quality due to environmental fluctuations limits the wider use of legumes such as pea. Breeding efforts are needed to optimize and stabilize seed nutritional value, which requires to identify the genetic determinism of seed protein plasticity in response to the environment. Towards this goal, we have studied the plasticity of protein content and composition of seeds from a collection of 200 Medicago truncatula ecotypes grown under four controlled conditions (optimal, drought, and winter/spring sowing). A quantitative analysis of one-dimensional protein profiles of these mature seeds was performed and plasticity indices were calculated from each abundant protein band. Genome-Wide Association Studies (GWAS) from these data identified major GWAS hotspots, from which a list of candidate genes was obtained. A Gene Ontology Enrichment Analysis revealed an over-representation of genes involved in several amino acid metabolic pathways. This led us to propose that environmental variations are likely to modulate amino acid balance, thus impacting seed protein composition. The selection of candidate genes for controlling the plasticity of seed protein composition was refined using transcriptomics data from developing Medicago truncatula seeds. The pea orthologs of key genes were identified for functional studies by mean of TILLING (Targeting Induced Local Lesions in Genomes) lines in this crop. We will present how this study highlighted mechanisms that could govern seed protein plasticity, providing new cues towards the stabilization of legume seed quality.

Keywords: GWAS, Medicago truncatula, plasticity, seed, storage proteins

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2619 [Keynote Talk]: Mathematical and Numerical Modelling of the Cardiovascular System: Macroscale, Mesoscale and Microscale Applications

Authors: Aymen Laadhari

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The cardiovascular system is centered on the heart and is characterized by a very complex structure with different physical scales in space (e.g. micrometers for erythrocytes and centimeters for organs) and time (e.g. milliseconds for human brain activity and several years for development of some pathologies). The development and numerical implementation of mathematical models of the cardiovascular system is a tremendously challenging topic at the theoretical and computational levels, inducing consequently a growing interest over the past decade. The accurate computational investigations in both healthy and pathological cases of processes related to the functioning of the human cardiovascular system can be of great potential in tackling several problems of clinical relevance and in improving the diagnosis of specific diseases. In this talk, we focus on the specific task of simulating three particular phenomena related to the cardiovascular system on the macroscopic, mesoscopic and microscopic scales, respectively. Namely, we develop numerical methodologies tailored for the simulation of (i) the haemodynamics (i.e., fluid mechanics of blood) in the aorta and sinus of Valsalva interacting with highly deformable thin leaflets, (ii) the hyperelastic anisotropic behaviour of cardiomyocytes and the influence of calcium concentrations on the contraction of single cells, and (iii) the dynamics of red blood cells in microvasculature. For each problem, we present an appropriate fully Eulerian finite element methodology. We report several numerical examples to address in detail the relevance of the mathematical models in terms of physiological meaning and to illustrate the accuracy and efficiency of the numerical methods.

Keywords: finite element method, cardiovascular system, Eulerian framework, haemodynamics, heart valve, cardiomyocyte, red blood cell

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2618 Cross-Cultural Experiences of South Asian Students in Chinese Universities: Predictors of the Students' Social-Media Engagements

Authors: Nadeem Akhtar, An Ran, Cornelius B. Pratt

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China’s President Xi' vision of Belt and Road Initiative, an infrastructural project of development and connectivity, is attracting international students to Chinese universities, with Pakistan and India among the top-10 countries of origin of those students (Ministry of Education China, 2018). An additional factor in international students’ interest in Chinese universities is their improving global rankings of Chinese universities. Against that backdrop, this study addresses two overarching questions: (a) What factors explain South Asian students’ study-away experiences, particularly in their multicultural environments? and (b) What role do new media play in their adaptation to that environment? This study is guided by Stephen’s (2011) theoretical model, which suggests that social networks influence immigrants’ interactions with host and home culture. The present study used a structured questionnaire distributed through both WeChat and other online platforms to international students studying in Chinese universities. Preliminary results are threefold: (a) that the frequency of use of social media is a predictor of the level of adjustment of the students to their multicultural environment; (b) that social engagement with their international-student peers is a moderating factor in their experiential outcomes; and (c) length of stay in Chinese universities, surprisingly, was not a predictor of adaptation. A major implication of these findings is that, even though social media tend to be criticized for contributing to anomie and to diminishing social capital among youths and millennials, they can be poignant tools for cultural adaptation, particularly among international students in China. It remains to be seen if such outcomes occur among international students in other countries or world regions.

Keywords: adaptation, China's Belt and Road Initiative, international students, social media

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2617 Flood Modeling in Urban Area Using a Well-Balanced Discontinuous Galerkin Scheme on Unstructured Triangular Grids

Authors: Rabih Ghostine, Craig Kapfer, Viswanathan Kannan, Ibrahim Hoteit

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Urban flooding resulting from a sudden release of water due to dam-break or excessive rainfall is a serious threatening environment hazard, which causes loss of human life and large economic losses. Anticipating floods before they occur could minimize human and economic losses through the implementation of appropriate protection, provision, and rescue plans. This work reports on the numerical modelling of flash flood propagation in urban areas after an excessive rainfall event or dam-break. A two-dimensional (2D) depth-averaged shallow water model is used with a refined unstructured grid of triangles for representing the urban area topography. The 2D shallow water equations are solved using a second-order well-balanced discontinuous Galerkin scheme. Theoretical test case and three flood events are described to demonstrate the potential benefits of the scheme: (i) wetting and drying in a parabolic basin (ii) flash flood over a physical model of the urbanized Toce River valley in Italy; (iii) wave propagation on the Reyran river valley in consequence of the Malpasset dam-break in 1959 (France); and (iv) dam-break flood in October 1982 at the town of Sumacarcel (Spain). The capability of the scheme is also verified against alternative models. Computational results compare well with recorded data and show that the scheme is at least as efficient as comparable second-order finite volume schemes, with notable efficiency speedup due to parallelization.

Keywords: dam-break, discontinuous Galerkin scheme, flood modeling, shallow water equations

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2616 Equilibrium, Kinetics, and Thermodynamic Studies on Heavy Metal Biosorption by Trichoderma Species

Authors: Sobia Mushtaq, Firdaus E. Bareen, Asma Tayyeb

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This study conducted to investigate the metal biosorption potential of indigenous Trichoderma species (T. harzianum KS05T01, T. longibrachiatum KS09T03, Trichoderma sp KS17T09., T. viridi KS17T011, T. atrobruneo KS21T014, and T. citrinoviride) that have been isolated from contaminated soil of Kasur Tannery Waste Management Agency. The effect of different biosorption parameters as initial metal ion concentration, pH, contact time , and temperature of incubation was investigated on the biosorption potential of these species. The metal removal efficiency and (E%) and metal uptake capacity (mg/g) increased along with the increase of initial metal concentration in media. The Trichoderma species can tolerate and survive under heavy metal stress up to 800mg/L. Among the two isotherm models were applied on the biosorption data, Langmuir isotherm model and Freundlich isotherm model, maximum correlation coefficients values (R 2 ) of 1was found for Langmuir model, which showed the better fitted model for the Trichoderma biosorption. The metal biosorption was increased with the increase of temperature and pH of the media. The maximum biosorption was observed between 25-30 o C and at pH 6.-7.5, while the biosorption rate was increased from 3-6 days of incubation, and then the rate of biosorption was slowed down. The biosorption data was better fitted for Pseudo kinetic first order during the initial days of biosorption. Thermodynamic parameters as standard Gibbs free energy (G), standard enthalpy change (H), and standard entropy (S) were calculated. The results confirmed the heavy metal biosorption by Trichoderma species was endothermic and spontaneous reaction in nature. The FTIR spectral analysis and SEM-EDX analysis of the treated and controlled mycelium revealed the changes in the active functional sites and morphological variations of the outer surface. The data analysis envisaged that high metal tolerance exhibited by Trichoderma species indicates its potential as efficacious and successful mediator for bioremediation of the heavy metal polluted environments.

Keywords: heavy metal, fungal biomass, biosorption, kinetics

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2615 Design, Analysis and Obstacle Avoidance Control of an Electric Wheelchair with Sit-Sleep-Seat Elevation Functions

Authors: Waleed Ahmed, Huang Xiaohua, Wilayat Ali

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The wheelchair users are generally exposed to physical and psychological health problems, e.g., pressure sores and pain in the hip joint, associated with seating posture or being inactive in a wheelchair for a long time. Reclining Wheelchair with back, thigh, and leg adjustment helps in daily life activities and health preservation. The seat elevating function of an electric wheelchair allows the user (lower limb amputation) to reach different heights. An electric wheelchair is expected to ease the lives of the elderly and disable people by giving them mobility support and decreasing the percentage of accidents caused by users’ narrow sight or joystick operation errors. Thus, this paper proposed the design, analysis and obstacle avoidance control of an electric wheelchair with sit-sleep-seat elevation functions. A 3D model of a wheelchair is designed in SolidWorks that was later used for multi-body dynamic (MBD) analysis and to verify driving control system. The control system uses the fuzzy algorithm to avoid the obstacle by getting information in the form of distance from the ultrasonic sensor and user-specified direction from the joystick’s operation. The proposed fuzzy driving control system focuses on the direction and velocity of the wheelchair. The wheelchair model has been examined and proven in MSC Adams (Automated Dynamic Analysis of Mechanical Systems). The designed fuzzy control algorithm is implemented on Gazebo robotic 3D simulator using Robotic Operating System (ROS) middleware. The proposed wheelchair design enhanced mobility and quality of life by improving the user’s functional capabilities. Simulation results verify the non-accidental behavior of the electric wheelchair.

Keywords: fuzzy logic control, joystick, multi body dynamics, obstacle avoidance, scissor mechanism, sensor

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2614 Series Network-Structured Inverse Models of Data Envelopment Analysis: Pitfalls and Solutions

Authors: Zohreh Moghaddas, Morteza Yazdani, Farhad Hosseinzadeh

Abstract:

Nowadays, data envelopment analysis (DEA) models featuring network structures have gained widespread usage for evaluating the performance of production systems and activities (Decision-Making Units (DMUs)) across diverse fields. By examining the relationships between the internal stages of the network, these models offer valuable insights to managers and decision-makers regarding the performance of each stage and its impact on the overall network. To further empower system decision-makers, the inverse data envelopment analysis (IDEA) model has been introduced. This model allows the estimation of crucial information for estimating parameters while keeping the efficiency score unchanged or improved, enabling analysis of the sensitivity of system inputs or outputs according to managers' preferences. This empowers managers to apply their preferences and policies on resources, such as inputs and outputs, and analyze various aspects like production, resource allocation processes, and resource efficiency enhancement within the system. The results obtained can be instrumental in making informed decisions in the future. The top result of this study is an analysis of infeasibility and incorrect estimation that may arise in the theory and application of the inverse model of data envelopment analysis with network structures. By addressing these pitfalls, novel protocols are proposed to circumvent these shortcomings effectively. Subsequently, several theoretical and applied problems are examined and resolved through insightful case studies.

Keywords: inverse models of data envelopment analysis, series network, estimation of inputs and outputs, efficiency, resource allocation, sensitivity analysis, infeasibility

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2613 Interaction between Space Syntax and Agent-Based Approaches for Vehicle Volume Modelling

Authors: Chuan Yang, Jing Bie, Panagiotis Psimoulis, Zhong Wang

Abstract:

Modelling and understanding vehicle volume distribution over the urban network are essential for urban design and transport planning. The space syntax approach was widely applied as the main conceptual and methodological framework for contemporary vehicle volume models with the help of the statistical method of multiple regression analysis (MRA). However, the MRA model with space syntax variables shows a limitation in vehicle volume predicting in accounting for the crossed effect of the urban configurational characters and socio-economic factors. The aim of this paper is to construct models by interacting with the combined impact of the street network structure and socio-economic factors. In this paper, we present a multilevel linear (ML) and an agent-based (AB) vehicle volume model at an urban scale interacting with space syntax theoretical framework. The ML model allowed random effects of urban configurational characteristics in different urban contexts. And the AB model was developed with the incorporation of transformed space syntax components of the MRA models into the agents’ spatial behaviour. Three models were implemented in the same urban environment. The ML model exhibit superiority over the original MRA model in identifying the relative impacts of the configurational characters and macro-scale socio-economic factors that shape vehicle movement distribution over the city. Compared with the ML model, the suggested AB model represented the ability to estimate vehicle volume in the urban network considering the combined effects of configurational characters and land-use patterns at the street segment level.

Keywords: space syntax, vehicle volume modeling, multilevel model, agent-based model

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2612 Design Transformation to Reduce Cost in Irrigation Using Value Engineering

Authors: F. S. Al-Anzi, M. Sarfraz, A. Elmi, A. R. Khan

Abstract:

Researchers are responding to the environmental challenges of Kuwait in localized, innovative, effective and economic ways. One of the vital and significant examples of the natural challenges is lack or water and desertification. In this research, the project team focuses on redesigning a prototype, using Value Engineering Methodology, which would provide similar functionalities to the well-known technology of Waterboxx kits while reducing the capital and operational costs and simplifying the process of manufacturing and usability by regular farmers. The design employs used tires and recycled plastic sheets as raw materials. Hence, this approach is going to help not just fighting desertification but also helping in getting rid of ever growing huge tire dumpsters in Kuwait, as well as helping in avoiding hazards of tire fires yielding in a safer and friendlier environment. Several alternatives for implementing the prototype have been considered. The best alternative in terms of value has been selected after thorough Function Analysis System Technique (FAST) exercise has been developed. A prototype has been fabricated and tested in a controlled simulated lab environment that is being followed by real environment field testing. Water and soil analysis conducted on the site of the experiment to cross compare between the composition of the soil before and after the experiment to insure that the prototype being tested is actually going to be environment safe. Experimentation shows that the design was equally as effective as, and may exceed, the original design with significant savings in cost. An estimated total cost reduction using the VE approach of 43.84% over the original design. This cost reduction does not consider the intangible costs of environmental issue of waste recycling which many further intensify the total savings of using the alternative VE design. This case study shows that Value Engineering Methodology can be an important tool in innovating new designs for reducing costs.

Keywords: desertification, functional analysis, scrap tires, value engineering, waste recycling, water irrigation rationing

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2611 Machine Learning Prediction of Compressive Damage and Energy Absorption in Carbon Fiber-Reinforced Polymer Tubular Structures

Authors: Milad Abbasi

Abstract:

Carbon fiber-reinforced polymer (CFRP) composite structures are increasingly being utilized in the automotive industry due to their lightweight and specific energy absorption capabilities. Although it is impossible to predict composite mechanical properties directly using theoretical methods, various research has been conducted so far in the literature for accurate simulation of CFRP structures' energy-absorbing behavior. In this research, axial compression experiments were carried out on hand lay-up unidirectional CFRP composite tubes. The fabrication method allowed the authors to extract the material properties of the CFRPs using ASTM D3039, D3410, and D3518 standards. A neural network machine learning algorithm was then utilized to build a robust prediction model to forecast the axial compressive properties of CFRP tubes while reducing high-cost experimental efforts. The predicted results have been compared with the experimental outcomes in terms of load-carrying capacity and energy absorption capability. The results showed high accuracy and precision in the prediction of the energy-absorption capacity of the CFRP tubes. This research also demonstrates the effectiveness and challenges of machine learning techniques in the robust simulation of composites' energy-absorption behavior. Interestingly, the proposed method considerably condensed numerical and experimental efforts in the simulation and calibration of CFRP composite tubes subjected to compressive loading.

Keywords: CFRP composite tubes, energy absorption, crushing behavior, machine learning, neural network

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2610 Antimicrobial Activity of Sour Cherry Pomace

Authors: Sonja Djilas, Aleksandra Velićanski, Dragoljub Cvetković, Siniša Markov, Eva Lončar, Vesna Tumbas Šaponjac, Milica Vinčić

Abstract:

Due to high content of bioactive compounds, sour cherry possesses antioxidant and antimicrobial activity. Additionally, waste material from industrial processing of sour cherry is also a good source of bioactive compounds. The aim of this study was to screen the antimicrobial activity and determine the minimal inhibitory (MIC) and minimal bactericidal concentrations (MBC) of sour cherry pomace extract. Tested strains were Gram-negative bacteria (Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 14028 and wild isolates Escherichia coli and Salmonella sp.), Gram-positive bacteria (Staphylococcus aureus ATCC 11632, Bacillus cereus ATCC 10876 and wild isolates Staphylococcus saprophyticus and Bacillus sp.) and yeasts (Saccharomyces cerevisiae 112, Hefebank Weihenstephan and Candida albicans ATCC 10231). Antimicrobial activity was tested by disc-diffusion method and agar-well diffusion method. MIC and MBC were determined by microdilution method. Screening tests showed that Gram-negative bacteria were resistant to tested extract, with exception of Salmonella typhimurium and Salmonella sp. for which only zones of reduced growth appeared. However, Gram-positive bacteria were more sensitive where the highest clear zones appeared with 100 µl of extract applied. There was no activity against tested yeasts. MIC and MBC values were in the range 3.125-37.5 mg/ml and 6.25-100 mg/ml, respectively. The most susceptible strain was Staphylococcus aureus while the most resistant was Bacillus sp. where MBC was not found in tested concentration range. Sour cherry pomace possesses high antibacterial potential, which indicates that this waste material is a promising source of bioactive compounds and could be used as a functional food ingredient.

Keywords: antimicrobial activity, sour cherry, pomace, bioactive compounds

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2609 Monitoring of Cannabis Cultivation with High-Resolution Images

Authors: Levent Basayigit, Sinan Demir, Burhan Kara, Yusuf Ucar

Abstract:

Cannabis is mostly used for drug production. In some countries, an excessive amount of illegal cannabis is cultivated and sold. Most of the illegal cannabis cultivation occurs on the lands far from settlements. In farmlands, it is cultivated with other crops. In this method, cannabis is surrounded by tall plants like corn and sunflower. It is also cultivated with tall crops as the mixed culture. The common method of the determination of the illegal cultivation areas is to investigate the information obtained from people. This method is not sufficient for the determination of illegal cultivation in remote areas. For this reason, more effective methods are needed for the determination of illegal cultivation. Remote Sensing is one of the most important technologies to monitor the plant growth on the land. The aim of this study is to monitor cannabis cultivation area using satellite imagery. The main purpose of this study was to develop an applicable method for monitoring the cannabis cultivation. For this purpose, cannabis was grown as single or surrounded by the corn and sunflower in plots. The morphological characteristics of cannabis were recorded two times per month during the vegetation period. The spectral signature library was created with the spectroradiometer. The parcels were monitored with high-resolution satellite imagery. With the processing of satellite imagery, the cultivation areas of cannabis were classified. To separate the Cannabis plots from the other plants, the multiresolution segmentation algorithm was found to be the most successful for classification. WorldView Improved Vegetative Index (WV-VI) classification was the most accurate method for monitoring the plant density. As a result, an object-based classification method and vegetation indices were sufficient for monitoring the cannabis cultivation in multi-temporal Earthwiev images.

Keywords: Cannabis, drug, remote sensing, object-based classification

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2608 Opposed Piston Engine Crankshaft Strength Calculation Using Finite Element Method

Authors: Konrad Pietrykowski, Michał Gęca, Michał Bialy

Abstract:

The paper presents the results of the crankshaft strength simulation. The crankshaft was taken from the opposed piston engine. Calculations were made using finite element method (FEM) in Abaqus software. This program allows to perform strength tests of individual machine parts as well as their assemblies. The crankshaft that was used in the calculations will be used in the two-stroke aviation research aircraft engine. The assumptions for the calculations were obtained from the AVL Boost software, from one-dimensional engine cycle model and from the multibody model using the method developed in the MSC Adams software. The research engine will be equipped with 3 combustion chambers and two crankshafts. In order to shorten the calculation time, only one crankcase analysis was performed. The cut of the shaft has been selected with the greatest forces resulting from the engine operation. Calculations were made for two cases. For maximum piston force when maximum bending load occurs and for the maximum torque. Cast iron material was adopted. For this material, Poisson's number, density, and Young's modulus were determined. The computational grid contained of 1,977,473 Tet elements. This type of elements was chosen because of the complex design of the crankshaft. Results are presented in the form of stress distributions maps and displacements on the surface and inside the geometry of the shaft. The results show the places of tension stresses, however, no stresses are exceeded at any place. The shaft can thus be applied to the engine in its present form. Acknowledgement: This work has been realized in the cooperation with The Construction Office of WSK 'PZL-KALISZ’ S.A. and is part of Grant Agreement No. POIR.01.02.00-00-0002/15 financed by the Polish National Centre for Research and Development.

Keywords: aircraft diesel engine, crankshaft, finite element method, two-stroke engine

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2607 Research on Container Housing: A New Form of Informal Housing on Urban Temporary Land

Authors: Lufei Mao, Hongwei Chen, Zijiao Chai

Abstract:

Informal housing is a widespread phenomenon in developing countries. In many newly-emerging cities in China, rapid urbanization leads to an influx of population as well as a shortage of housing. Under this background, container housing, a new form of informal housing, gradually appears on a small scale on urban temporary land in recent years. Container housing, just as its name implies, transforms containers into small houses that allow migrant workers group to live in it. Scholars in other countries have established sound theoretical frameworks for informal housing study, but the research fruits seem rather limited on this small scale housing form. Unlike the cases in developed countries, these houses, which are outside urban planning, bring about various environmental, economic, social and governance issues. Aiming to figure out this new-born housing form, a survey mainly on two container housing settlements in Hangzhou, China was carried out to gather the information of them. Based on this thorough survey, the paper concludes the features and problems of infrastructure, environment and social communication of container housing settlements. The result shows that these containers were lacking of basic facilities and were restricted in a small mess temporary land. Moreover, because of the deficiency in management, the rental rights of these containers might not be guaranteed. Then the paper analyzes the factors affecting the formation and evolution of container housing settlements. It turns out that institutional and policy factors, market factors and social factors were the main three factors that affect the formation. At last, the paper proposes some suggestions for the governance of container housing and the utility pattern of urban temporary land.

Keywords: container housing, informal housing, urban temporary land, urban governance

Procedia PDF Downloads 259
2606 Spatial Planning and Tourism Development with Sustainability Model of the Territorial Tourist with Land Use Approach

Authors: Mehrangiz Rezaee, Zabih Charrahi

Abstract:

In the last decade, with increasing tourism destinations and tourism growth, we are witnessing the widespread impacts of tourism on the economy, environment and society. Tourism and its related economy are now undergoing a transformation and as one of the key pillars of business economics, it plays a vital role in the world economy. Activities related to tourism and providing services appropriate to it in an area, like many economic sectors, require the necessary context on its origin. Given the importance of tourism industry and tourism potentials of Yazd province in Iran, it is necessary to use a proper procedure for prioritizing different areas for proper and efficient planning. One of the most important goals of planning is foresight and creating balanced development in different geographical areas. This process requires an accurate study of the areas and potential and actual talents, as well as evaluation and understanding of the relationship between the indicators affecting the development of the region. At the global and regional level, the development of tourist resorts and the proper distribution of tourism destinations are needed to counter environmental impacts and risks. The main objective of this study is the sustainable development of suitable tourism areas. Given that tourism activities in different territorial areas require operational zoning, this study deals with the evaluation of territorial tourism using concepts such as land use, fitness and sustainable development. It is essential to understand the structure of tourism development and the spatial development of tourism using land use patterns, spatial planning and sustainable development. Tourism spatial planning implements different approaches. However, the development of tourism as well as the spatial development of tourism is complex, since tourist activities can be carried out in different areas with different purposes. Multipurpose areas have great important for tourism because it determines the flow of tourism. Therefore, in this paper, by studying the development and determination of tourism suitability that is related to spatial development, it is possible to plan tourism spatial development by developing a model that describes the characteristics of tourism. The results of this research determine the suitability of multi-functional territorial tourism development in line with spatial planning of tourism.

Keywords: land use change, spatial planning, sustainability, territorial tourist, Yazd

Procedia PDF Downloads 187
2605 Effects of Bed Type, Corm Weight and Lifting Time on Quantitative and Qualitative Criteria of Saffron (Crocus sativus L.)

Authors: A. Mollafilabi, A. Koocheki, P. Rezvani Moghaddam, M. Nassiri Mahalati

Abstract:

In order to study the effects of corm weights and times of corm lifting saffron in different planting beds, an experiment was conducted as Factorial layout based on a Randomized Complete Block Design with three replications at the Fadak Research Center of Agricultural Research in Food Science during 2010. Treatments were two corm weights (8-10, 10 < g), two planting beds (stone wool and peat moss) and five levels of lifting time (mi-June, early July, mid-July, early August and mid-August). No. of corms were 457 corms.m-2 and for 40 days and were stored for 90 days in incubation, 85% relative humidity and 25°C temperature in the darkness. Then, saffron corms were transferred to growth chamber with 17 °C in 8 hours light and 16 hours darkness. Characteristics were number of flower, fresh weight of flower, dry weight of flower, fresh and dry weight of stigma, fresh and dry weight of style, fresh and dry weight of stigma+style and Picrocrocin, Safronal and Crocin contents of saffron were measured. Results showed that the corm weight, bed type and time of corm lifting had significant effects on economical yield of saffron such as picked flowers, dry weight of stigma and fresh weight of flowers. The highest saffron economical yield was obtained in interaction of corm weight, 10 g, peat moss and lifting time in mid-June as much as 5.2 g.m-2. This yield is 11 fold of average yield of Iranian farms. Picrocrocin, Safranal and Crocin contents was graded as excellent thread in peat moss under controlled conditions compared with ISO Standard of 203.

Keywords: corm density, dry stigma, safranal-flowering, yield saffron

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2604 Manganese Imidazole Complexes: Electrocatalytic Hydrogen Production

Authors: Vishakha Kaim, Mookan Natarajan, Sandeep Kaur-Ghumaan

Abstract:

Hydrogen is one of the most abundant elements present on earth’s crust and considered to be the simplest element in existence. It is not found naturally as a gas on earth and thus has to be manufactured. Hydrogen can be produced from a variety of sources, i.e., water, fossil fuels, or biomass and it is a byproduct of many chemical processes. It is also considered as a secondary source of energy commonly referred to as an energy carrier. Though hydrogen is not widely used as a fuel, it still has the potential for greater use in the future as a clean and renewable source of energy. Electrocatalysis is one of the important source for the production of hydrogen which could contribute to this prominent challenge. Metals such as platinum and palladium are considered efficient for hydrogen production but with limited applications. As a result, a wide variety of metal complexes with earth abundant elements and varied ligand environments have been explored for the electrochemical production of hydrogen. In nature, [FeFe] hydrogenase enzyme present in DesulfoVibrio desulfuricans and Clostridium pasteurianum catalyses the reversible interconversion of protons and electrons into dihydrogen. Since the first structure for the enzyme was reported in 1990s, a range of iron complexes has been synthesized as structural and functional mimics of the enzyme active site. Mn is one of the most desirable element for sustainable catalytic transformations, immediately behind Fe and Ti. Only limited number manganese complexes have been reported in the last two decades as catalysts for proton reduction. Furthermore, redox reactions could be carried out in a facile manner, due to the capability of manganese complexes to be stable at different oxidation states. Herein are reported, four µ2-thiolate bridged manganese complexes [Mn₂(CO)₆(μ-S₂N₄C₁₄H₁₀)] 1, [Mn₂(CO)7(μ- S₂N₄C₁₄H₁₀)] 2, Mn₂(CO)₆(μ-S₄N₂C₁₄H₁₀)] 3 and [Mn₂(CO)(μ- S₄N₂C₁₄H₁₀)] 4 have been synthesized and characterized. The cyclic voltammograms of the complexes displayed irreversible reduction peaks in the range - 0.9 to -1.3 V (vs. Fc⁺/Fc in acetonitrile at 0.1 Vs⁻¹). The complexes were catalytically active towards proton reduction in the presence of trifluoroacetic acid as seen from electrochemical investigations.

Keywords: earth abundant, electrocatalytic, hydrogen, manganese

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