Search results for: Thomas Alexander
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 741

Search results for: Thomas Alexander

501 A Proposal to Integrate Spatially Explicit Ecosystem Services with Urban Metabolic Modelling

Authors: Thomas Elliot, Javier Babi Almenar, Benedetto Rugani

Abstract:

The integration of urban metabolism (UM) with spatially explicit ecosystem service (ES) stocks has the potential to advance sustainable urban development. It will correct the lack of spatially specificity of current urban metabolism models. Furthermore, it will include into UM not only the physical properties of material and energy stocks and flows, but also the implications to the natural capital that provides and maintains human well-being. This paper presents the first stages of a modelling framework by which urban planners can assess spatially the trade-offs of ES flows resulting from urban interventions of different character and scale. This framework allows for a multi-region assessment which takes into account sustainability burdens consequent to an urban planning event occurring elsewhere in the environment. The urban boundary is defined as the Functional Urban Audit (FUA) method to account for trans-administrative ES flows. ES are mapped using CORINE land use within the FUA. These stocks and flows are incorporated into a UM assessment method to demonstrate the transfer and flux of ES arising from different urban planning implementations.

Keywords: ecological economics, ecosystem services, spatial planning, urban metabolism

Procedia PDF Downloads 335
500 A Multicriteria Model for Sustainable Management in Agriculture

Authors: Basil Manos, Thomas Bournaris, Christina Moulogianni

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The European agricultural policy supports all member states to apply agricultural development plans for the development of their agricultural sectors. A specific measure of the agricultural development plans refers to young people in order to enter into the agricultural sector. This measure helps the participating young farmers in achieving maximum efficiency, using methods and environmentally friendly practices, by altering their farm plans. This study applies a Multicriteria Mathematical Programming (MCDA) model for the young farmers to find farm plans that achieve the maximum gross margin and the minimum environmental impacts (less use of fertilizers and irrigation water). The analysis was made in the region of Central Macedonia, Greece, among young farmers who have participated in the “Setting up Young Farmers” measure during 2007-2010. The analysis includes the implementation of the MCDA model for the farm plans optimization and the comparison of selected environmental indicators with those of the existent situation.

Keywords: multicriteria, optimum farm plans, environmental impacts, sustainable management

Procedia PDF Downloads 341
499 A Review on the Impact of Institutional Setting on Land Use Conflicts in Coastal Areas

Authors: Roni Susman, Thomas Weith

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This article explores how institutional setting, mainly from institutionalism, could clearly explain the understanding of land use conflict analysis in coastal areas and has been used in current practices. Institutional setting appears as a guideline that is committed by the stakeholders who are involved directly or indirectly in land management process. This paper is aimed to identify the setting of institutional and to measure how the conflicts occur, how the actors act and influence the process, how is the condition to apply the appropriate framework for adequate solution of land use conflict in coastal area in order to enhance better decisions. To reflect the current practice and use of theories a qualitative review of 150 scientific peer-reviewed papers regarding the issue of land use conflicts in coastal areas as well as institutional process is included. The selection of peer-reviewed papers is obtained through a structured literature survey of the recently published database in a way to investigate the variances of institutional between theory and practices specifically in the case of coastal land management.

Keywords: coastal areas, institutional settings, land use conflict, land governance, actors’ constellation, analytical framework

Procedia PDF Downloads 193
498 Simulation of Kinetic Friction in L-Bending of Sheet Metals

Authors: Maziar Ramezani, Thomas Neitzert, Timotius Pasang

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This paper aims at experimental and numerical investigation of springback behavior of sheet metals during L-bending process with emphasis on Stribeck-type friction modeling. The coefficient of friction in Stribeck curve depends on sliding velocity and contact pressure. The springback behavior of mild steel and aluminum alloy 6022-T4 sheets was studied experimentally and using numerical simulations with ABAQUS software with two types of friction model: Coulomb friction and Stribeck friction. The influence of forming speed on springback behavior was studied experimentally and numerically. The results showed that Stribeck-type friction model has better results in predicting springback in sheet metal forming. The FE prediction error for mild steel and 6022-T4 AA is 23.8%, 25.5% respectively, using Coulomb friction model and 11%, 13% respectively, using Stribeck friction model. These results show that Stribeck model is suitable for simulation of sheet metal forming especially at higher forming speed.

Keywords: friction, L-bending, springback, Stribeck curves

Procedia PDF Downloads 493
497 Determination of Economic and Ecological Potential of Bio Hydrogen Generated through Dark Photosynthesis Process

Authors: Johannes Full, Martin Reisinger, Alexander Sauer, Robert Miehe

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The use of biogenic residues for the biotechnological production of chemical energy carriers for electricity and heat generation as well as for mobile applications is an important lever for the shift away from fossil fuels towards a carbon dioxide neutral post-fossil future. A multitude of promising biotechnological processes needs, therefore, to be compared against each other. For this purpose, a multi-objective target system and a corresponding methodology for the evaluation of the underlying key figures are presented in this paper, which can serve as a basis for decisionmaking for companies and promotional policy measures. The methodology considers in this paper the economic and ecological potential of bio-hydrogen production using the example of hydrogen production from fruit and milk production waste with the purple bacterium R. rubrum (so-called dark photosynthesis process) for the first time. The substrate used in this cost-effective and scalable process is fructose from waste material and waste deposits. Based on an estimation of the biomass potential of such fructose residues, the new methodology is used to compare different scenarios for the production and usage of bio-hydrogen through the considered process. In conclusion, this paper presents, at the example of the promising dark photosynthesis process, a methodology to evaluate the ecological and economic potential of biotechnological production of bio-hydrogen from residues and waste.

Keywords: biofuel, hydrogen, R. rubrum, bioenergy

Procedia PDF Downloads 197
496 Analysis of Translational Ship Oscillations in a Realistic Environment

Authors: Chen Zhang, Bernhard Schwarz-Röhr, Alexander Härting

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To acquire accurate ship motions at the center of gravity, a single low-cost inertial sensor is utilized and applied on board to measure ship oscillating motions. As observations, the three axes accelerations and three axes rotational rates provided by the sensor are used. The mathematical model of processing the observation data includes determination of the distance vector between the sensor and the center of gravity in x, y, and z directions. After setting up the transfer matrix from sensor’s own coordinate system to the ship’s body frame, an extended Kalman filter is applied to deal with nonlinearities between the ship motion in the body frame and the observation information in the sensor’s frame. As a side effect, the method eliminates sensor noise and other unwanted errors. Results are not only roll and pitch, but also linear motions, in particular heave and surge at the center of gravity. For testing, we resort to measurements recorded on a small vessel in a well-defined sea state. With response amplitude operators computed numerically by a commercial software (Seaway), motion characteristics are estimated. These agree well with the measurements after processing with the suggested method.

Keywords: extended Kalman filter, nonlinear estimation, sea trial, ship motion estimation

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495 The Potential of Sentiment Analysis to Categorize Social Media Comments Using German Libraries

Authors: Felix Boehnisch, Alexander Lutz

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Based on the number of users and the amount of content posted daily, Facebook is considered the largest social network in the world. This content includes images or text posts from companies but also private persons, which are also commented on by other users. However, it can sometimes be difficult for companies to keep track of all the posts and the reactions to them, especially when there are several posts a day that contain hundreds to thousands of comments. To facilitate this, the following paper deals with the possible applications of sentiment analysis to social media comments in order to be able to support the work in social media marketing. In a first step, post comments were divided into positive and negative by a subjective rating, then the same comments were checked for their polarity value by the two german python libraries TextBlobDE and SentiWS and also grouped into positive, negative, or even neutral. As a control, the subjective classifications were compared with the machine-generated ones by a confusion matrix, and relevant quality criteria were determined. The accuracy of both libraries was not really meaningful, with 60% to 66%. However, many words or sentences were not evaluated at all, so there seems to be room for optimization to possibly get more accurate results. In future studies, the use of these specific German libraries can be optimized to gain better insights by either applying them to stricter cleaned data or by adding a sentiment value to emojis, which have been removed from the comments in advance, as they are not contained in the libraries.

Keywords: Facebook, German libraries, polarity, sentiment analysis, social media comments

Procedia PDF Downloads 183
494 Development of the Ontology of Engineering Design Complexity

Authors: Victor E. Lopez, L. Dale Thomas

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As engineered systems become more complex, the difficulty associated with predicting, developing, and operating engineered systems also increases, resulting in increased costs, failure rates, and unexpected consequences. Successfully managing the complexity of the system should reduce these negative consequences. The study of complexity in the context of engineering development has suffered due to the ambiguity of the nature of complexity, what makes a system complex and how complexity translates to real world engineering attributes and consequences. This paper argues that the use of an ontology of engineering design complexity would i) improve the clarity of the research being performed by allowing researchers to use a common conceptualization of complexity, with more precise terminology, and ii) elucidate the connections between certain types of complexity and their consequences for system development. The ontology comprises concepts of complexity found in the literature and the different relations that exists between them. The ontology maps different complexity concepts such as structural complexity, creation complexity, and information entropy, and then relates the to system aspects such as interfaces, development effort, and modularity. The ontology is represented using the Web Ontology Language (OWL). This paper presents the current status of the ontology of engineering design complexity, the main challenges encountered, and the future plans for the ontology.

Keywords: design complexity, ontology, design effort, complexity ontology

Procedia PDF Downloads 188
493 Prediction of Phonon Thermal Conductivity of F.C.C. Al by Molecular Dynamics Simulation

Authors: Leila Momenzadeh, Alexander V. Evteev, Elena V. Levchenko, Tanvir Ahmed, Irina Belova, Graeme Murch

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In this work, the phonon thermal conductivity of f.c.c. Al is investigated in detail in the temperature range 100 – 900 K within the framework of equilibrium molecular dynamics simulations making use of the Green-Kubo formalism and one of the most reliable embedded-atom method potentials. It is found that the heat current auto-correlation function of the f.c.c. Al model demonstrates a two-stage temporal decay similar to the previously observed for f.c.c Cu model. After the first stage of decay, the heat current auto-correlation function of the f.c.c. Al model demonstrates a peak in the temperature range 100-800 K. The intensity of the peak decreases as the temperature increases. At 900 K, it transforms to a shoulder. To describe the observed two-stage decay of the heat current auto-correlation function of the f.c.c. Al model, we employ decomposition model recently developed for phonon-mediated thermal transport in a monoatomic lattice. We found that the electronic contribution to the total thermal conductivity of f.c.c. Al dominates over the whole studied temperature range. However, the phonon contribution to the total thermal conductivity of f.c.c. Al increases as temperature decreases. It is about 1.05% at 900 K and about 12.5% at 100 K.

Keywords: aluminum, gGreen-Kubo formalism, molecular dynamics, phonon thermal conductivity

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492 A Dialectical Behavioral Therapy Adaptation in Reducing Depression, Anxiety, and Self-Harm in Older Adults

Authors: Valerie Alexander, Amanda Gutierrez, Veronica Campbell, Dara Schwartz, B. Charles Tatum

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It has long been assumed that personality disorders (PD) originate in adolescence or early adulthood and that the maladaptive behaviors significantly attenuate over time. The Diagnostic and Statistical Manual of Mental Disorders-5 supports early onset of PD and views the pattern of behaviors as enduring and stable. The premise of this study is that PD may not always begin early in life, that behaviors may change over the lifespan, and that current treatment modalities may be beneficial in seniors. Self-injurious behaviors (SIB) exhibited earlier in life may, in older adults, be manifested in less overt high-risk behaviors but by refusal to take medication and get necessary medical treatment. Dialectical Behavioral Therapy is a well-known treatment modality for teaching emotional regulation and distress tolerance and thus reducing self-injurious behaviors yet very little has been studied about SIB and treatment in older adults. The population for this study was older adults, with a history of SIB, a PD, and depression and/or anxiety. Participants learned an adapted version of Dialectical Behavioral Therapy (DBT) as developed by DBT trained therapists. The results provided clinical potentials for the efficacy of DBT to reduce SIB, decrease depression and anxiety in the older adult population.

Keywords: anxiety, depression, dialectical behavioral therapy, personality disorders, self-harm behavior, treatment in older adults

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491 Factors Affecting Sustainable Water Management in Water-Challenged Societies: Case Study of Doha Qatar

Authors: L. Mathew, D. Thomas

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Qatar is a desert country with scarce fresh water resources, low rainfall and very high evaporation rate. It meets the majority of its water requirement through desalination process which is very expensive. Pressures are expected to mount on account of high population growth rate and demands posed by being the venue for 2022 FIFA World cup. This study contributes towards advancing the knowledge of the factors affecting sustainable water consumption in water-challenged societies by examining the case of Doha, Qatar. Survey research methods have been predominantly used for this research. Surveys were conducted using self-administered questionnaires. Focused group interviews and personal interviews with Qatar’s residents were also used to obtain deeper insights. Salient socio-cultural factors that drive the water consumption behavior of the public and which in turn affect sustainable water management practices are determined. Suggestions for reducing water consumption as well as fiscal and punitive measures to curb overuse and misuse of water are also identified.

Keywords: Middle East, Qatar, water consumption, water management, sustainability

Procedia PDF Downloads 245
490 Availability and the Utilization of Recreational Facilities for Prison Inmate Rehabilitation

Authors: Thomas Ejobowah Boye, Philip Oghenetega Ekpon

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The paper examines the availability and the utilization of recreational facilities for prison inmate’s rehabilitation in Nigeria. In order to carry out the study the researchers visited sampled prisons in the six geo-political zones in Nigeria. Instant assessment of available recreational facilities was carried out. Inmates were asked to tick a self-design questionnaire that was validated by experts in the Departments of Physical and Health Education, Delta State University and the College of Physical Education, Mosogar on available recreational facilities and activities engaged in by them. The data collected was subjected to percentage analysis. The study revealed that there is little or no standard recreational facilities in all the prisons visited. Considering the role physical activities play in the overall development of individuals physically, mentally, emotionally, morally, and socially it was recommended that the authorities of the Nigerian prisons should as a matter of urgency include recreational activities as a means of reforming and rehabilitating prison inmates. To achieve the desire to rehabilitate prison inmates the researchers also recommended that facilities and equipment should be made available in all prisons in Nigeria.

Keywords: facility, prison, recreation, rehabilitation

Procedia PDF Downloads 598
489 Elements of Socio-Ecological Knowledge for Sustainable Fisheries Management: An Analysis of Chakara Fishery Management in South West India

Authors: Antony Thomas Vanchipurrakkal

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Common property resource like fisheries is conserved and managed by fishermen with the help of Local Ecological Knowledge system. Various forms of Social and Ecological elements adapted to formularize management of Chakara fishery. This study tries for a better understanding of elements involved in fishery management in India, such traditional knowledge system practicing within the fishing communities for management and conservation of the marine resources. Participatory Rural Appraisal technique is applied to seize the traditional knowledge system in central Kerala coastal region, India. Socio-Ecological Analysis framework is used for the study. This paper discusses that traditional knowledge systems of chakara fishery and discloses need for inclusive governance system. The paper also discusses adaptation of different elements of the ecological, biological and institutional knowledge system in local ecological knowledge for sustain the fishery. A framework is formulized based on elements operating in chakara fishery management.

Keywords: common property, fisheries, India, local ecological knowledge, management

Procedia PDF Downloads 414
488 Random Matrix Theory Analysis of Cross-Correlation in the Nigerian Stock Exchange

Authors: Chimezie P. Nnanwa, Thomas C. Urama, Patrick O. Ezepue

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In this paper we use Random Matrix Theory to analyze the eigen-structure of the empirical correlations of 82 stocks which are consistently traded in the Nigerian Stock Exchange (NSE) over a 4-year study period 3 August 2009 to 26 August 2013. We apply the Marchenko-Pastur distribution of eigenvalues of a purely random matrix to investigate the presence of investment-pertinent information contained in the empirical correlation matrix of the selected stocks. We use hypothesised standard normal distribution of eigenvector components from RMT to assess deviations of the empirical eigenvectors to this distribution for different eigenvalues. We also use the Inverse Participation Ratio to measure the deviation of eigenvectors of the empirical correlation matrix from RMT results. These preliminary results on the dynamics of asset price correlations in the NSE are important for improving risk-return trade-offs associated with Markowitz’s portfolio optimization in the stock exchange, which is pursued in future work.

Keywords: correlation matrix, eigenvalue and eigenvector, inverse participation ratio, portfolio optimization, random matrix theory

Procedia PDF Downloads 344
487 Identification of Location Parameters for Different User Types of the Inner-City Building Stock: An Austrian Example

Authors: Bernhard Bauer, Thomas Meixner, Amir Dini, Detlef Heck

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The inner city building stock is characterized by different types of buildings of different decades and centuries and different types of historical constructions. Depending on the natural growth of a city, those types are often located in downtown areas and the surrounding suburbs. Since the population is becoming older and the variation of the different social requirements spread with the so-called 'Silver Society', city quarters have to be seen alternatively. If an area is very attractive for young students to live there because of the busy nightlife, it might not be suitable for the older society. To identify 'Location Types A, B, C' for different user groups, qualitative interviews with 24 citizens of the city of Graz (Austria) have been carried out, in order to identify the most important values for making a location or city quarter 'A', 'B', or 'C'. Furthermore these acknowledgements have been put into a softwaretool for predicting locations that are the most suitable for certain user groups. On the other hands side, investors or owners of buildings can use the tool for determining the most suitable user group for the location of their building or construction project in order to adapt the project or building stock to the requirements of the users.

Keywords: building stock, location parameters, inner city population, built environment

Procedia PDF Downloads 313
486 Prefectorial Participation in Inclusive School Governance: A Shrewd Strategy for Building an Inclusive Society

Authors: Thomas Jerome Yeboah

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Inclusive school leadership is not a standalone project. It is spread across a broad array of individual leaders in the school. Successful inclusive education thrives on collaborative, shared, and participatory leadership. School prefects are generally not included in leadership discourses in respect of the implementation of inclusive education and the benefits inherent in it, yet they live at the closest proximity to the learners and wield much influence over them. The purpose of this study was to investigate how the participation of school prefects in inclusive school governance could be used as a strategy to prepare them to champion the course of individuals who live with disability and special needs in order to build a more inclusive society. The exploratory study employed a purposive sampling technique to select ten (10) school prefects from five (5) inclusive schools in Ghana. Semi-structured interview was used to glean information from the selected participants to answer the research questions raised in the study. Results from the study were thematically analysed. The study concluded that the school prefects could be agents of societal transformation who would be capable of creating an environment where those with disability and special needs would be accepted by society as ‘normal.’

Keywords: inclusive society, participation, inclusive school leadership, societal transformation, school prefects

Procedia PDF Downloads 200
485 An Inflammatory Mediated Hypothesis of COVID-19 Psychosis

Authors: Hilary P. Stevenson, Alexander J. Hayek, Amie Dereczyk

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In this case report, we provide an example of an asymptomatic COVID-19 positive patient who presented with new-onset psychosis with severe paranoid delusions. He was seen in our ED after ingesting isopropyl alcohol which he reported was an attempt to escape presumed attackers, which at the time was logical to the patient. The patient’s family had COVID-19 symptoms that corresponded to those typically observed from the Omicron variant. The patient was treated successfully, within ten days, with Risperdal twice-daily dosing resulting in the resolution of the patient’s delusions and improved insight regarding the events that led to his hospitalization. In this work, we examine possible contributing factors to new-onset psychosis in the context of COVID-19, a phenomenon that is becoming increasingly notable in the literature. One area of importance is the already established inflammatory hypothesis of psychosis in which defects in the innate immune system, which result in its overactivation, may play a role in a typical first-episode psychosis, in addition to subsequent episodes. Given that COVID-19 is known to cause derangements in the innate immune system, such as cytokine storm reactions, this link may be critical in further understanding the etiologies of new-onset COVID-19 psychosis and its risk factors. Also included in this work is a brief review of antipsychotic interventions that have been described in the literature to date for the first episode of COVID-19-related psychosis. This will explore the potential of some antipsychotics to innately diminish the production of pro-inflammatory cytokines, further enhancing their usefulness in COVID-19 first-episode psychosis patients.

Keywords: COVID-19, first break psychosis, inflammatory hypothesis of psychosis, Risperdal

Procedia PDF Downloads 99
484 Comparison of Power Consumption of WiFi Inbuilt Internet of Things Device with Bluetooth Low Energy

Authors: Darshana Thomas, Edward Wilkie, James Irvine

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The Internet of things (IoT) is currently a highly researched topic, especially within the context of the smart home. These are small sensors that are capable of gathering data and transmitting it to a server. The majority of smart home products use protocols such as ZigBee or Bluetooth Low Energy (BLE). As these small sensors are increasing in number, the need to implement these with much more capable and ubiquitous transmission technology is necessary. The high power consumption is the reason that holds these small sensors back from using other protocols such as the most ubiquitous form of communication, WiFi. Comparing the power consumption of existing transmission technologies to one with WiFi inbuilt, would provide a better understanding for choosing between these technologies. We have developed a small IoT device with WiFi capability and proven that it is much more efficient than the first protocol, 433 MHz. We extend our work in this paper and compare WiFi power consumption with the other most widely used protocol BLE. The experimental results in this paper would conclude whether the developed prototype is capable in terms of power consumption to replace the existing protocol BLE with WiFi.

Keywords: bluetooth, internet of things (IoT), power consumption, WiFi

Procedia PDF Downloads 267
483 Dispersion-Less All Reflective Split and Delay Unit for Ultrafast Metrology

Authors: Akansha Tyagi, Mehar S. Sidhu, Ankur Mandal, Sanjay Kapoor, Sunil Dahiya, Jan M. Rost, Thomas Pfeifer, Kamal P. Singh

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An all-reflective split and delay unit is designed for dispersion free measurement of broadband ultrashort pulses using a pair of reflective knife edge prism for splitting and recombining of the measuring pulse. It is based on symmetrical wavefront splitting of the measuring pulse having two separate arms to independently shape both split parts. We have validated our delay line with NIR –femtosecond pulse measurement centered at 800 nm using second harmonic-Interferometric frequency resolved optical gating (SH-IFROG). The delay line is compact, easy to align and provides attosecond stability and precision and thus make it more versatile for wide range of applications in ultrafast measurements. We envision that the present delay line will find applications in IR-IR controlling for high harmonic generation (HHG) and attosecond IR-XUV pump-probe measurements with solids and gases providing attosecond resolution and wide delay range.

Keywords: HHG, nonlinear optics, pump-probe spectroscopy, ultrafast metrology

Procedia PDF Downloads 201
482 Hypoxia Tolerance, Longevity and Cancer-Resistance in the Mole Rat Spalax – a Liver Transcriptomics Approach

Authors: Hanno Schmidt, Assaf Malik, Anne Bicker, Gesa Poetzsch, Aaron Avivi, Imad Shams, Thomas Hankeln

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The blind subterranean mole rat Spalax shows a remarkable tolerance to hypoxia, cancer-resistance and longevity. Unravelling the genomic basis of these adaptations will be important for biomedical applications. RNA-Seq gene expression data were obtained from normoxic and hypoxic Spalax and rat liver tissue. Hypoxic Spalax broadly downregulates genes from major liver function pathways. This energy-saving response is likely a crucial adaptation to low oxygen levels. In contrast, the hypoxiasensitive rat shows massive upregulation of energy metabolism genes. Candidate genes with plausible connections to the mole rat’s phenotype, such as important key genes related to hypoxia-tolerance, DNA damage repair, tumourigenesis and ageing, are substantially higher expressed in Spalax than in rat. Comparative liver transcriptomics highlights the importance of molecular adaptations at the gene regulatory level in Spalax and pinpoints a variety of starting points for subsequent functional studies.

Keywords: cancer, hypoxia, longevity, transcriptomics

Procedia PDF Downloads 158
481 Estimating Bridge Deterioration for Small Data Sets Using Regression and Markov Models

Authors: Yina F. Muñoz, Alexander Paz, Hanns De La Fuente-Mella, Joaquin V. Fariña, Guilherme M. Sales

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The primary approach for estimating bridge deterioration uses Markov-chain models and regression analysis. Traditional Markov models have problems in estimating the required transition probabilities when a small sample size is used. Often, reliable bridge data have not been taken over large periods, thus large data sets may not be available. This study presents an important change to the traditional approach by using the Small Data Method to estimate transition probabilities. The results illustrate that the Small Data Method and traditional approach both provide similar estimates; however, the former method provides results that are more conservative. That is, Small Data Method provided slightly lower than expected bridge condition ratings compared with the traditional approach. Considering that bridges are critical infrastructures, the Small Data Method, which uses more information and provides more conservative estimates, may be more appropriate when the available sample size is small. In addition, regression analysis was used to calculate bridge deterioration. Condition ratings were determined for bridge groups, and the best regression model was selected for each group. The results obtained were very similar to those obtained when using Markov chains; however, it is desirable to use more data for better results.

Keywords: concrete bridges, deterioration, Markov chains, probability matrix

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480 Feasibility of a Biopolymer as Lightweight Aggregate in Perlite Concrete

Authors: Ali A. Sayadi, Thomas R. Neitzert, G. Charles Clifton

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Lightweight concrete is being used in the construction industry as a building material in its own right. Ultra-lightweight concrete can be applied as a filler and support material for the manufacturing of composite building materials. This paper is about the development of a stable and reproducible ultra-lightweight concrete with the inclusion of poly-lactic acid (PLA) beads and assessing the feasibility of PLA as a lightweight aggregate that will deliver advantages such as a more eco-friendly concrete and a non-petroleum polymer aggregate. In total, sixty-three samples were prepared and the effectiveness of mineral admixture, curing conditions, water-cement ratio, PLA ratio, EPS ratio and perlite ratio on compressive strength of perlite concrete are studied. The results show that PLA particles are sensitive to alkali environment of cement paste and considerably shrank and lost their strength. A higher compressive strength and a lower density was observed when expanded polystyrene (EPS) particles replaced PLA beads. In addition, a set of equations is proposed to estimate the water-cement ratio, cement content and compressive strength of perlite concrete.

Keywords: perlite concrete, poly-lactic acid (pla), expanded polystyrene (eps), concrete

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479 Design of a Recombinant Expression System for Bacterial Cellulose Production

Authors: Gizem Buldum, Alexander Bismarck, Athanasios Mantalaris

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Cellulose is the most abundant biopolymer on earth and it is currently being utilised in a multitude of industrial applications. Over the last 30 years, attention has been paid to the bacterial cellulose (BC), since BC exhibits unique physical, chemical and mechanical properties when compared to plant-based cellulose, including high purity and biocompatibility. Although Acetobacter xylinum is the most efficient producer of BC, it’s long doubling time results in insufficient yields of the cellulose production. This limits widespread and continued use of BC. In this study, E. coli BL21 (DE3) or E. coli HMS cells are selected as host organisms for the expression of bacterial cellulose synthase operon (bcs) of A.xylinum. The expression system is created based on pET-Duet1 and pCDF plasmid vectors, which carry bcs operon. The results showed that all bcs genes were successfully transferred and expressed in E.coli strains. The expressions of bcs proteins were shown by SDS and Native page analyses. The functionality of the bcs operon was proved by congo red binding assay. The effect of culturing temperature and the inducer concentration (IPTG) on cell growth and plasmid stability were monitored. The percentage of plasmid harboring cells induced with 0.025 mM IPTG was obtained as 85% at 22˚C in the end of 10-hr culturing period. It was confirmed that the high output cellulose production machinery of A.xylinum can be transferred into other organisms.

Keywords: bacterial cellulose, biopolymer, recombinant expression system, production

Procedia PDF Downloads 402
478 Clonal Evaluation of Malignant Mesothelioma

Authors: Sabahattin Comertpay, Sandra Pastorino, Rosanna Mezzapelle, Mika Tanji, Oriana Strianese, Andrea Napolitano, Tracey Weigel, Joseph Friedberg, Paul Sugarbaker, Thomas Krausz, Ena Wang, Amy Powers, Giovanni Gaudino, Harvey I. Pass, Fatmagul Ozcelik, Barbara L. Parsons, Haining Yang, Michele Carbone

Abstract:

Tumors are thought to be monoclonal in origin. This paradigm arose decades ago, primarily from the study of hematopoietic malignancies and sarcomas. The clonal origin of malignant mesothelioma (MM), a deadly cancer resistant to the current therapies, has not been investigated. Examination of the pleura from patients with MM shows often the presence of multiple pleural nodules, raising the question of whether they represent independent or metastatic growth processes. To investigate the clonality patterns of MM, we used the HUMARA (Human Androgen Receptor) assay to examine 14 sporadic and 2 familial Malignant Mesotheliomas (MM). Of 16 specimens studied, 15 were informative and 14/15 revealed two electrophoretically distinct methylated HUMARA alleles, indicating a polyclonal origin for these tumors. This discovery has important clinical implications, because an accurate assessment of tumor clonality is key to the design of novel molecular strategies for the treatment of MM.

Keywords: malignant mesothelioma, clonal origin, HUMARA, sarcomas

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477 Coupling of Two Discretization Schemes for the Lattice Boltzmann Equation

Authors: Tobias Horstmann, Thomas Le Garrec, Daniel-Ciprian Mincu, Emmanuel Lévêque

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Despite the efficiency and low dissipation of the stream-collide formulation of the Lattice Boltzmann (LB) algorithm, which is nowadays implemented in many commercial LBM solvers, there are certain situations, e.g. mesh transition, in which a classical finite-volume or finite-difference formulation of the LB algorithm still bear advantages. In this paper, we present an algorithm that combines the node-based streaming of the distribution functions with a second-order finite volume discretization of the advection term of the BGK-LB equation on a uniform D2Q9 lattice. It is shown that such a coupling is possible for a multi-domain approach as long as the overlap, or buffer zone, between two domains, is achieved on at least 2Δx. This also implies that a direct coupling (without buffer zone) of a stream-collide and finite-volume LB algorithm on a single grid is not stable. The critical parameter in the coupling is the CFL number equal to 1 that is imposed by the stream-collide algorithm. Nevertheless, an explicit filtering step on the finite-volume domain can stabilize the solution. In a further investigation, we demonstrate how such a coupling can be used for mesh transition, resulting in an intrinsic conservation of mass over the interface.

Keywords: algorithm coupling, finite volume formulation, grid refinement, Lattice Boltzmann method

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476 Deformation of Particle-Laden Droplet in Viscous Liquid under DC Electric Fields

Authors: Khobaib Khobaib, Alexander Mikkelsen, Zbigniew Rozynek

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Electric fields have proven useful for inducing droplet deformation and to structure particles adsorbed at droplet interfaces. In this experimental research, direct current electric fields were applied to deform particle-covered droplets made out of silicone oil and immersed in castor oil. The viscosity of the drop and surrounding fluid were changed by external heating. We designed an experimental system in such a way that electric field-induced electrohydrodynamic (EHD) flows were asymmetric and only present on one side of the drop, i.e., the droplet adjoined a washer and adhered to one of the electrodes constituting the sample cell. The study investigated the influence of viscosity on the steady-state deformation magnitude of particle-laden droplets, droplet compression, and relaxation, as well as particle arrangements at drop interfaces. Initially, before the application of an electric field, we changed the viscosity of the fluids by heating the sample cell at different temperatures. The viscosity of the fluids was varied by changing the temperature of the fluids from 25 to 50°C. Under the application of a uniform electric field of strength 290 Vmm⁻¹, electric stress was induced at the drop interface, yielding drop deformation. In our study, we found that by lowering the fluid viscosity, the velocity of the EHD flows was increased, which also increases the deformation of the drop.

Keywords: drop deformation and relaxation, electric field, electrohydrodynamic flow, particle assembly, viscosity

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475 A Digital Twin Approach for Sustainable Territories Planning: A Case Study on District Heating

Authors: Ahmed Amrani, Oussama Allali, Amira Ben Hamida, Felix Defrance, Stephanie Morland, Eva Pineau, Thomas Lacroix

Abstract:

The energy planning process is a very complex task that involves several stakeholders and requires the consideration of several local and global factors and constraints. In order to optimize and simplify this process, we propose a tool-based iterative approach applied to district heating planning. We build our tool with the collaboration of a French territory using actual district data and implementing the European incentives. We set up an iterative process including data visualization and analysis, identification and extraction of information related to the area concerned by the operation, design of sustainable planning scenarios leveraging local renewable and recoverable energy sources, and finally, the evaluation of scenarios. The last step is performed by a dynamic digital twin replica of the city. Territory’s energy experts confirm that the tool provides them with valuable support towards sustainable energy planning.

Keywords: climate change, data management, decision support, digital twin, district heating, energy planning, renewables, smart city

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474 Research and Innovation Centre

Authors: Krasimir Ivanov, Tonyo Tonev, Nguyen Nguyen, Alexander Peltekov, Anyo Mitkov

Abstract:

Maize is among the most economically important crops and at the same time one of the most sensitive to soil deficiency in zinc. In this paper, the impact of the foliar zinc application in the form of zinc hydroxy nitrate suspension on the micro and macro elements partitioning in maize leaves and grain was studied during spring maize season, 2017. The impact of the foliar zinc fertilization on the grain yield and quality was estimated too. The experiment was performed by the randomized block design with 8 variants in 3 replications. Seven suspension solutions whit different Zn concentration were used, including ZnO suspension and zinc hydroxyl nitrate alone or nixed with other nutrients. Fertilization and irrigation were the same for all variants. The Zn content and the content of selected micro (Cu, Fe) and macro (Ca, Mg, P and K) elements in maize leaves were determined two weeks after the first spraying (5-6 sheets), two weeks after the second spraying (9-10 sheets) and after harvesting. It was concluded that the synthesized zinc hydroxy nitrate demonstrates potential as the long-term foliar fertilizer. A significant (p < 0.05) effect of zinc accumulation in maize leaves by foliar zinc application during the first growth stage was found, followed by its reutilization to other plants organs during the second growth stage. Significant export of Cu, P, and K from lower and middle leaves was observed. The content of Ca and Mg remains constant in the whole longevity period, while the content of Fe decreases sharply.

Keywords: foliar fertilization, zinc hydroxy nitrate, maize, zinc

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473 CNN-Based Compressor Mass Flow Estimator in Industrial Aircraft Vapor Cycle System

Authors: Justin Reverdi, Sixin Zhang, Saïd Aoues, Fabrice Gamboa, Serge Gratton, Thomas Pellegrini

Abstract:

In vapor cycle systems, the mass flow sensor plays a key role for different monitoring and control purposes. However, physical sensors can be inaccurate, heavy, cumbersome, expensive, or highly sensitive to vibrations, which is especially problematic when embedded into an aircraft. The conception of a virtual sensor, based on other standard sensors, is a good alternative. This paper has two main objectives. Firstly, a data-driven model using a convolutional neural network is proposed to estimate the mass flow of the compressor. We show that it significantly outperforms the standard polynomial regression model (thermodynamic maps) in terms of the standard MSE metric and engineer performance metrics. Secondly, a semi-automatic segmentation method is proposed to compute the engineer performance metrics for real datasets, as the standard MSE metric may pose risks in analyzing the dynamic behavior of vapor cycle systems.

Keywords: deep learning, convolutional neural network, vapor cycle system, virtual sensor

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472 Teacher Professional Development –Current Practices in a Secondary School in Brunei Darussalam

Authors: Shanthi Thomas

Abstract:

This research paper presents the current practices of teacher professional development, perceived as beneficial by teachers themselves, in a private secondary school in Brunei Darussalam. This is part of the findings of a larger qualitative study on teacher empowerment, using ethnographic methods for data collection, i.e. participant observation, interviews and document analysis. The field work was carried out over a period of six months in 2013. An analysis of the field data revealed multiple pathways of teacher professional development existing in the school. The results indicate that school leaders, the teacher community in the school, students, and the teachers themselves were the agents in a school that facilitated teacher empowerment. Besides contributing to the knowledge base on teacher professional development, the results of this study provides directions for educational policy makers in their efforts to enhance professional development in secondary schools of similar characteristics. For school leaders and the teacher community, these findings offer guidelines for maximizing the opportunities for these professional development practices, by strengthening collegiality and by using the existing structures optimally for the benefit of all concerned.

Keywords: colleagues and the wider teacher community, school leaders, self-driven professional development, teacher professional development

Procedia PDF Downloads 413