Search results for: Cassava production technologies
500 Disaggregating Communities and the Making of Factional States: Evidence from Joint Forest Management in Sundarban, India
Authors: Amrita Sen
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In the face of a growing insurgent movement and the perceived failure of the state and the market towards sustainable resource management, a range of decentralized forest management policies was formulated in the last two decades, which recognized the need for community representations within the statutory methods of forest management. The recognition conceded on the virtues of ecological sustainability and traditional environmental knowledge, which were considered to be the principal repositories of the forest dependent communities. The present study, in the light of empirical insights, reflects on the contemporary disjunctions between the preconceived communitarian ethic in environmentalism and the lived reality of forest based life-worlds. Many of the popular as well as dominant ideologies, which have historically shaped the conceptual and theoretical understanding of sociology, needs further perusal in the context of the emerging contours of empirical knowledge, which lends opportunities for substantive reworking and analysis. The image of the community appears to be one of those concepts, an identity which has for long defined perspectives and processes associated with people living together harmoniously in small physical spaces. Through an ethnographic account of the implementation of Joint Forest Management (JFM) in a forest fringe village in Sundarban, the study explores the ways in which the idea of ‘community’ gets transformed through the process of state-making, rendering the necessity of its departure from the standard, conventional definition of homogeneity and internal equity. The study necessitates an attention towards the anthropology of micro-politics, disaggregating an essentially constructivist anthropology of ‘collective identities’, which can render the visibility of political mobilizations plausible within the seemingly culturalist production of communities. The two critical questions that the paper seeks to ask in this context are: how the ‘local’ is constituted within community based conservation practices? Within the efforts of collaborative forest management, how accurately does the depiction of ‘indigenous environmental knowledge’, subscribe to its role of sustainable conservation practices? Reflecting on the execution of JFM in Sundarban, the study critically explores the ways in which the state ceases to be ‘trans-national’ and interacts with the rural life-worlds through its local factions. Simultaneously, the study attempts to articulate the scope of constructing a competing representation of community, shaped by increasing political negotiations and bureaucratic alignments which strains against the usual preoccupations with tradition primordiality and non material culture as well as the amorous construction of indigeneity.Keywords: community, environmentalism, JFM, state-making, identities, indigenous
Procedia PDF Downloads 198499 Using Lysosomal Immunogenic Cell Death to Target Breast Cancer via Xanthine Oxidase/Micro-Antibody Fusion Protein
Authors: Iulianna Taritsa, Kuldeep Neote, Eric Fossel
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Lysosome-induced immunogenic cell death (LIICD) is a powerful mechanism of targeting cancer cells that kills circulating malignant cells and primes the host’s immune cells against future remission. Current immunotherapies for cancer are limited in preventing recurrence – a gap that can be bridged by training the immune system to recognize cancer neoantigens. Lysosomal leakage can be induced therapeutically to traffic antigens from dying cells to dendritic cells, which can later present those tumorigenic antigens to T cells. Previous research has shown that oxidative agents administered in the tumor microenvironment can initiate LIICD. We generated a fusion protein between an oxidative agent known as xanthine oxidase (XO) and a mini-antibody specific for EGFR/HER2-sensitive breast tumor cells. The anti-EGFR single domain antibody fragment is uniquely sourced from llama, which is functional without the presence of a light chain. These llama micro-antibodies have been shown to be better able to penetrate tissues and have improved physicochemical stability as compared to traditional monoclonal antibodies. We demonstrate that the fusion protein created is stable and can induce early markers of immunogenic cell death in an in vitro human breast cancer cell line (SkBr3). Specifically, we measured overall cell death, as well as surface-expressed calreticulin, extracellular ATP release, and HMGB1 production. These markers are consensus indicators of ICD. Flow cytometry, luminescence assays, and ELISA were used respectively to quantify biomarker levels between treated versus untreated cells. We also included a positive control group of SkBr3 cells dosed with doxorubicin (a known inducer of LIICD) and a negative control dosed with cisplatin (a known inducer of cell death, but not of the immunogenic variety). We looked at each marker at various time points after cancer cells were treated with the XO/antibody fusion protein, doxorubicin, and cisplatin. Upregulated biomarkers after treatment with the fusion protein indicate an immunogenic response. We thus show the potential for this fusion protein to induce an anticancer effect paired with an adaptive immune response against EGFR/HER2+ cells. Our research in human cell lines here provides evidence for the success of the same therapeutic method for patients and serves as the gateway to developing a new treatment approach against breast cancer.Keywords: apoptosis, breast cancer, immunogenic cell death, lysosome
Procedia PDF Downloads 199498 New Teaching Tools for a Modern Representation of Chemical Bond in the Course of Food Science
Authors: Nicola G. G. Cecca
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In Italian IPSSEOAs, high schools that give a vocational education to students that will work in the field of Enogastronomy and Hotel Management, the course of Food Science allows the students to start and see food as a mixture of substances that they will transform during their profession. These substances are characterized not only by a chemical composition but also by a molecular structure that makes them nutritionally active. But the increasing number of new products proposed by Food Industry, the modern techniques of production and transformation, the innovative preparations required by customers have made many information reported in the most wide spread Food Science textbooks not up-to-date or too poor for the people who will work in catering sector. Often Authors offer information aged to Bohr’s Atomic Model and to the ‘Octet Rule’ proposed by G.N. Lewis to describe the Chemical Bond, without giving any reference to new as Orbital Atomic Model and Molecular Orbital Theory that, in the meantime, start to be old themselves. Furthermore, this antiquated information precludes an easy understanding of a wide range of properties of nutritive substances and many reactions in which the food constituents are involved. In this paper, our attention is pointed out to use GEOMAG™ to represent the dynamics with which the chemical bond is formed during the synthesis of the molecules. GEOMAG™ is a toy, produced by the Swiss Company Geomagword S.A., pointed to stimulate in children, aged between 6-10 years, their fantasy and their handling ability and constituted by metallic spheres and metallic magnetic bars coated by coloured plastic materials. The simulation carried out with GEOMAG™ is based on the similitude existing between the Coulomb’s force and the magnetic attraction’s force and in particular between the formulae with which they are calculated. The electrostatic force (F in Newton) that allows the formation of the chemical bond can be calculated by mean Fc = kc q1 q2/d2 where: q1 e q2 are the charge of particles [in Coulomb], d is the distance between the particles [in meters] and kc is the Coulomb’s constant. It is surprising to observe that the attraction’s force (Fm) acting between the magnetic extremities of GEOMAG™ used to simulate the chemical bond can be calculated in the same way by using the formula Fm = km m1 m2/d2 where: m1 e m2 represent the strength of the poles [A•m], d is the distance between the particles [m], km = μ/4π in which μ is the magnetic permeability of medium [N•A-2]. The magnetic attraction can be tested by students by trying to keep the magnetic elements of GEOMAG™ separate by hands or trying to measure by mean an appropriate dynamometric system. Furthermore, by using a dynamometric system to measure the magnetic attraction between the GEOMAG™ elements is possible draw a graphic F=f(d) to verify that the curve obtained during the simulation is very similar to that one hypnotized, around the 1920’s by Linus Pauling to describe the formation of H2+ in according with Molecular Orbital Theory.Keywords: chemical bond, molecular orbital theory, magnetic attraction force, GEOMAG™
Procedia PDF Downloads 267497 The Development of Explicit Pragmatic Knowledge: An Exploratory Study
Authors: Aisha Siddiqa
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The knowledge of pragmatic practices in a particular language is considered key to effective communication. Unlike one’s native language where this knowledge is acquired spontaneously, more conscious attention is required to learn second language pragmatics. Traditional foreign language (FL) classrooms generally focus on the acquisition of vocabulary and lexico-grammatical structures, neglecting pragmatic functions that are essential for effective communication in the multilingual networks of the modern world. In terms of effective communication, of particular importance is knowledge of what is perceived as polite or impolite in a certain language, an aspect of pragmatics which is not perceived as obligatory but is nonetheless indispensable for successful intercultural communication and integration. While learning a second language, the acquisition of politeness assumes more prominence as the politeness norms and practices vary according to language and culture. Therefore, along with focusing on the ‘use’ of politeness strategies, it is crucial to examine the ‘acquisition’ and the ‘acquisitional development’ of politeness strategies by second language learners, particularly, by lower proficiency leaners as the norms of politeness are usually focused in lower levels. Hence, there is an obvious need for a study that not only investigates the acquisition of pragmatics by young FL learners using innovative multiple methods; but also identifies the potential causes of the gaps in their development. The present research employs a cross sectional design to explore the acquisition of politeness by young English as a foreign language learners (EFL) in France; at three levels of secondary school learning. The methodology involves two phases. In the first phase a cartoon oral production task (COPT) is used to elicit samples of requests from young EFL learners in French schools. These data are then supplemented by a) role plays, b) an analysis of textbooks, and c) video recordings of classroom activities. This mixed method approach allows us to explore the repertoire of politeness strategies the learners possess and delve deeper into the opportunities available to learners in classrooms to learn politeness strategies in requests. The paper will provide the results of the analysis of COPT data for 250 learners at three different stages of English as foreign language development. Data analysis is based on categorization of requests developed in CCSARP project. The preliminary analysis of the COPT data shows that there is substantial evidence of pragmalinguistic development across all levels but the developmental process seems to gain momentum in the second half of the secondary school period as compared to the early period at school. However, there is very little evidence of sociopragmatic development. The study aims to document the current classroom practices in France by looking at the development of young EFL learner’s politeness strategies across three levels of secondary schools.Keywords: acquisition, English, France, interlanguage pragmatics, politeness
Procedia PDF Downloads 424496 The Reliability and Shape of the Force-Power-Velocity Relationship of Strength-Trained Males Using an Instrumented Leg Press Machine
Authors: Mark Ashton Newman, Richard Blagrove, Jonathan Folland
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The force-velocity profile of an individual has been shown to influence success in ballistic movements, independent of the individuals' maximal power output; therefore, effective and accurate evaluation of an individual’s F-V characteristics and not solely maximal power output is important. The relatively narrow range of loads typically utilised during force-velocity profiling protocols due to the difficulty in obtaining force data at high velocities may bring into question the accuracy of the F-V slope along with predictions pertaining to the maximum force that the system can produce at a velocity of null (F₀) and the theoretical maximum velocity against no load (V₀). As such, the reliability of the slope of the force-velocity profile, as well as V₀, has been shown to be relatively poor in comparison to F₀ and maximal power, and it has been recommended to assess velocity at loads closer to both F₀ and V₀. The aim of the present study was to assess the relative and absolute reliability of an instrumented novel leg press machine which enables the assessment of force and velocity data at loads equivalent to ≤ 10% of one repetition maximum (1RM) through to 1RM during a ballistic leg press movement. The reliability of maximal and mean force, velocity, and power, as well as the respective force-velocity and power-velocity relationships and the linearity of the force-velocity relationship, were evaluated. Sixteen male strength-trained individuals (23.6 ± 4.1 years; 177.1 ± 7.0 cm; 80.0 ± 10.8 kg) attended four sessions; during the initial visit, participants were familiarised with the leg press, modified to include a mounted force plate (Type SP3949, Force Logic, Berkshire, UK) and a Micro-Epsilon WDS-2500-P96 linear positional transducer (LPT) (Micro-Epsilon, Merseyside, UK). Peak isometric force (IsoMax) and a dynamic 1RM, both from a starting position of 81% leg length, were recorded for the dominant leg. Visits two to four saw the participants carry out the leg press movement at loads equivalent to ≤ 10%, 30%, 50%, 70%, and 90% 1RM. IsoMax was recorded during each testing visit prior to dynamic F-V profiling repetitions. The novel leg press machine used in the present study appears to be a reliable tool for measuring F and V-related variables across a range of loads, including velocities closer to V₀ when compared to some of the findings within the published literature. Both linear and polynomial models demonstrated good to excellent levels of reliability for SFV and F₀ respectively, with reliability for V₀ being good using a linear model but poor using a 2nd order polynomial model. As such, a polynomial regression model may be most appropriate when using a similar unilateral leg press setup to predict maximal force production capabilities due to only a 5% difference between F₀ and obtained IsoMax values with a linear model being best suited to predict V₀.Keywords: force-velocity, leg-press, power-velocity, profiling, reliability
Procedia PDF Downloads 58495 Lightweight Sheet Molding Compound Composites by Coating Glass Fiber with Cellulose Nanocrystals
Authors: Amir Asadi, Karim Habib, Robert J. Moon, Kyriaki Kalaitzidou
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There has been considerable interest in cellulose nanomaterials (CN) as polymer and polymer composites reinforcement due to their high specific modulus and strength, low density and toxicity, and accessible hydroxyl side groups that can be readily chemically modified. The focus of this study is making lightweight composites for better fuel efficiency and lower CO2 emission in auto industries with no compromise on mechanical performance using a scalable technique that can be easily integrated in sheet molding compound (SMC) manufacturing lines. Light weighting will be achieved by replacing part of the heavier components, i.e. glass fibers (GF), with a small amount of cellulose nanocrystals (CNC) in short GF/epoxy composites made using SMC. CNC will be introduced as coating of the GF rovings prior to their use in the SMC line. The employed coating method is similar to the fiber sizing technique commonly used and thus it can be easily scaled and integrated to industrial SMC lines. This will be an alternative route to the most techniques that involve dispersing CN in polymer matrix, in which the nanomaterials agglomeration limits the capability for scaling up in an industrial production. We have demonstrated that incorporating CNC as a coating on GF surface by immersing the GF in CNC aqueous suspensions, a simple and scalable technique, increases the interfacial shear strength (IFSS) by ~69% compared to the composites produced by uncoated GF, suggesting an enhancement of stress transfer across the GF/matrix interface. As a result of IFSS enhancement, incorporation of 0.17 wt% CNC in the composite results in increases of ~10% in both elastic modulus and tensile strength, and 40 % and 43 % in flexural modulus and strength respectively. We have also determined that dispersing 1.4 and 2 wt% CNC in the epoxy matrix of short GF/epoxy SMC composites by sonication allows removing 10 wt% GF with no penalty on tensile and flexural properties leading to 7.5% lighter composites. Although sonication is a scalable technique, it is not quite as simple and inexpensive as coating the GF by passing through an aqueous suspension of CNC. In this study, the above findings are integrated to 1) investigate the effect of CNC content on mechanical properties by passing the GF rovings through CNC aqueous suspension with various concentrations (0-5%) and 2) determine the optimum ratio of the added CNC to the removed GF to achieve the maximum possible weight reduction with no cost on mechanical performance of the SMC composites. The results of this study are of industrial relevance, providing a path toward producing high volume lightweight and mechanically enhanced SMC composites using cellulose nanomaterials.Keywords: cellulose nanocrystals, light weight polymer-matrix composites, mechanical properties, sheet molding compound (SMC)
Procedia PDF Downloads 225494 The Audiovisual Media as a Metacritical Ludicity Gesture in the Musical-Performatic and Scenic Works of Caetano Veloso and David Bowie
Authors: Paulo Da Silva Quadros
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This work aims to point out comparative parameters between the artistic production of two exponents of the contemporary popular culture scene: Caetano Veloso (Brazil) and David Bowie (England). Both Caetano Veloso and David Bowie were pioneers in establishing an aesthetic game between various artistic expressions at the service of the music-visual scene, that is, the conceptual interconnections between several forms of aesthetic processes, such as fine arts, theatre, cinema, poetry, and literature. There are also correlations in their expressive attitudes of art, especially regarding the dialogue between the fields of art and politics (concern with respect to human rights, human dignity, racial issues, tolerance, gender issues, and sexuality, among others); the constant tension and cunning game between market, free expression and critical sense; the sophisticated, playful mechanisms of metalanguage and aesthetic metacritique. Fact is that both of them almost came to cooperate with each other in the 1970s when Caetano was in exile in England, and when both had at the same time the same music producer, who tried to bring them closer, noticing similar aesthetic qualities in both artistic works, which was later glimpsed by some music critics. Among many of the most influential issues in Caetano's and Bowie's game of artistic-aesthetic expression are, for example, the ideas advocated by the sensation of strangeness (Albert Camus), art as transcendence (Friedrich Nietzsche), the deconstruction and reconstruction of auratic reconfiguration of artistic signs (Walter Benjamin and Andy Warhol). For deepen more theoretical issues, the following authors will be used as supportive interpretative references: Hans-Georg Gadamer, Immanuel Kant, Friedrich Schiller, Johan Huizinga. In addition to the aesthetic meanings of Ars Ludens characteristics of the two artists, the following supporting references will be also added: the question of technique (Martin Heidegger), the logic of sense (Gilles Deleuze), art as an event and the sense of the gesture of art ( Maria Teresa Cruz), the society of spectacle (Guy Debord), Verarbeitung and Durcharbeitung (Sigmund Freud), the poetics of interpretation and the sign of relation (Cremilda Medina). The purpose of such interpretative references is to seek to understand, from a cultural reading perspective (cultural semiology), some significant elements in the dynamics of aesthetic and media interconnections of both artists, which made them as some of the most influential interlocutors in contemporary music aesthetic thought, as a playful vivid experience of life and art.Keywords: Caetano Veloso, David Bowie, music aesthetics, symbolic playfulness, cultural reading
Procedia PDF Downloads 168493 Validating Quantitative Stormwater Simulations in Edmonton Using MIKE URBAN
Authors: Mohamed Gaafar, Evan Davies
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Many municipalities within Canada and abroad use chloramination to disinfect drinking water so as to avert the production of the disinfection by-products (DBPs) that result from conventional chlorination processes and their consequential public health risks. However, the long-lasting monochloramine disinfectant (NH2Cl) can pose a significant risk to the environment. As, it can be introduced into stormwater sewers, from different water uses, and thus freshwater sources. Little research has been undertaken to monitor and characterize the decay of NH2Cl and to study the parameters affecting its decomposition in stormwater networks. Therefore, the current study was intended to investigate this decay starting by building a stormwater model and validating its hydraulic and hydrologic computations, and then modelling water quality in the storm sewers and examining the effects of different parameters on chloramine decay. The presented work here is only the first stage of this study. The 30th Avenue basin in Southern Edmonton was chosen as a case study, because the well-developed basin has various land-use types including commercial, industrial, residential, parks and recreational. The City of Edmonton has already built a MIKE-URBAN stormwater model for modelling floods. Nevertheless, this model was built to the trunk level which means that only the main drainage features were presented. Additionally, this model was not calibrated and known to consistently compute pipe flows higher than the observed values; not to the benefit of studying water quality. So the first goal was to complete modelling and updating all stormwater network components. Then, available GIS Data was used to calculate different catchment properties such as slope, length and imperviousness. In order to calibrate and validate this model, data of two temporary pipe flow monitoring stations, collected during last summer, was used along with records of two other permanent stations available for eight consecutive summer seasons. The effect of various hydrological parameters on model results was investigated. It was found that model results were affected by the ratio of impervious areas. The catchment length was tested, however calculated, because it is approximate representation of the catchment shape. Surface roughness coefficients were calibrated using. Consequently, computed flows at the two temporary locations had correlation coefficients of values 0.846 and 0.815, where the lower value pertained to the larger attached catchment area. Other statistical measures, such as peak error of 0.65%, volume error of 5.6%, maximum positive and negative differences of 2.17 and -1.63 respectively, were all found in acceptable ranges.Keywords: stormwater, urban drainage, simulation, validation, MIKE URBAN
Procedia PDF Downloads 299492 Teaching of Entrepreneurship and Innovation in Brazilian Universities
Authors: Marcelo T. Okano, Oduvaldo Vendrametto, Osmildo S. Santos, Marcelo E. Fernandes, Heide Landi
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Teaching of entrepreneurship and innovation in Brazilian universities has increased in recent years due to several factors such as the emergence of disciplines like biotechnology increased globalization reduced basic funding and new perspectives on the role of the university in the system of knowledge production Innovation is increasingly seen as an evolutionary process that involves different institutional spheres or sectors in society Entrepreneurship is a milestone on the road towards economic progress, and makes a huge contribution towards the quality and future hopes of a sector, economy or even a country. Entrepreneurship is as important in small and medium-sized enterprises (SMEs) and local markets as in large companies, and national and international markets, and is just as key a consideration for public companies as or private organizations. Entrepreneurship helps to encourage the competition in the current environment that leads to the effects of globalization. There is an increasing tendency for government policy to promote entrepreneurship for its apparent economic benefit. Accordingly, governments seek to employ entrepreneurship education as a means to stimulate increased levels of economic activity. Entrepreneurship education and training (EET) is growing rapidly in universities and colleges throughout the world, and governments are supporting it both directly and through funding major investments in advice-provision to would-be entrepreneurs and existing small businesses. The Triple Helix of university–industry–government relations is compared with alternative models for explaining the current research system in its social contexts. Communications and negotiations between institutional partners generate an overlay that increasingly reorganizes the underlying arrangements. To achieve the objective of this research was a survey of the literature on the entrepreneurship and innovation and then a field research with 100 students of Fatec. To collect the data needed for analysis, we used the exploratory research of a qualitative nature. We asked to respondents what degree of knowledge over ten related to entrepreneurship and innovation topics, responses were answered in a Likert scale with 4 levels, none, small, medium and large. We can conclude that the terms such as entrepreneurship and innovation are known by most students because the university propagates them across disciplines, lectures, and institutes innovation. The more specific items such as canvas and Design thinking model are unknown by most respondents. The importance of the University in teaching innovation and entrepreneurship in the transmission of this knowledge to the students in order to equalize the knowledge. As a future project, these items will be re-evaluated to create indicators for measuring the knowledge level.Keywords: Brazilian universities, entrepreneurship, innovation, entrepreneurship, globalization
Procedia PDF Downloads 507491 Immune Disregulation in Inflammatory Skin Diseases with Comorbid Metabolic Disorders
Authors: Roman Khanferyan, Levon Gevorkyan, Ivan Radysh
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Skin barrier dysfunction induces multiple inflammatory skin diseases. Epidemiological studies clearly support the link between most dermatological pathologies, immune disorders and metabolic disorders. Among them most common are psoriasis (PS) and Atopic dermatitis (AD). Psoriasis is a chronic immune-mediated inflammatory skin disease that affects 1.5 to 3.0% of the world's population. Comorbid metabolic disorders play an important role in the progression of PS and AD, as well. It is well known that PS, AD and overweight/obesity are associated with common pathophysiological mechanisms of mild chronic inflammation. The goal of the study was to study the immune disturbances in patients with PS, AD and comorbid metabolic disorders. To study the prevalence of comorbidity of PS and AD (data from 1406 patient’s histories of diseases) were analyzed. The severity of the disease is assessed using the PASI index (Psoriasis Area and Severity Index). 59 patients with psoriasis of different localizations of lesions and severity, as well as with different body mass index (BMI), were examined. The determination of the concentration of pro-inflammatory cytokines (IL-6, IL-8, IFNγ, IL-17, L-18 and TNFa) and chemokines (RANTES, IP-10, MCP-1 and Eotaxin) in sera and supernatants of 48h-cultivated peripheral blood mononuclear cell (PBMC) of psoriasis patients and healthy volunteers (36 adults) have been carried out by multiplex assay (Luminex Corporation, USA). It has been demonstrated that 42% of PS patients had comorbidity with different types of atopies. The most common was bronchial asthma and allergic rhinitis. At the same time, the prevalence of AD in PS patients was determined in 8.7% of patients. It has been shown that serum levels of all studied cytokines (IL-6, IL-8, IFNγ, IL-17, L-18 and TNF) in most of the studied patients were higher in PS patients than in those with AD and healthy controls (p<0.05). An in vitro synthesis of the IL-6 and IFNγ by PBMC demonstrated similar results to those determined in blood sera. There was a high correlation between BMI, immune mediators and the concentrations of adipokines and chemokines (p<0.05). The concentrations of Leptin and Resistin in obese psoriatic patients were greater by 28.6% and 17%, respectively, compared to non-obese psoriatic patients. In obese patients with psoriasis the serum levels of adiponectin were decreased up to 1.3-fold. The mean serum RANTES, IP-10, MCP-1, EOTAXIN levels in obese psoriatic patients were decreased by up to 13.1%, 21.9%, 40.4% and 28.2%, respectively. Similar results have been demonstrated in AD patients with comorbid overweight and obesity. Thus, the study demonstrated the important role of cytokines and chemokines dysregulation in inflammatory skin diseases, especially in patients with comorbid obesity and overweight. Metabolic disorders promote the severity of PS and AD, highly increase immune dysregulation, and synthesis of adipokines, which correlates with the production of proinflammatory immune mediators in comorbid obesity and overweight.Keywords: psoriasis, atopic dermatitis, pro-inflammatory cytokines, chemokines, comorbid obesity
Procedia PDF Downloads 36490 IEEE802.15.4e Based Scheduling Mechanisms and Systems for Industrial Internet of Things
Authors: Ho-Ting Wu, Kai-Wei Ke, Bo-Yu Huang, Liang-Lin Yan, Chun-Ting Lin
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With the advances in advanced technology, wireless sensor network (WSN) has become one of the most promising candidates to implement the wireless industrial internet of things (IIOT) architecture. However, the legacy IEEE 802.15.4 based WSN technology such as Zigbee system cannot meet the stringent QoS requirement of low powered, real-time, and highly reliable transmission imposed by the IIOT environment. Recently, the IEEE society developed IEEE 802.15.4e Time Slotted Channel Hopping (TSCH) access mode to serve this purpose. Furthermore, the IETF 6TiSCH working group has proposed standards to integrate IEEE 802.15.4e with IPv6 protocol smoothly to form a complete protocol stack for IIOT. In this work, we develop key network technologies for IEEE 802.15.4e based wireless IIoT architecture, focusing on practical design and system implementation. We realize the OpenWSN-based wireless IIOT system. The system architecture is divided into three main parts: web server, network manager, and sensor nodes. The web server provides user interface, allowing the user to view the status of sensor nodes and instruct sensor nodes to follow commands via user-friendly browser. The network manager is responsible for the establishment, maintenance, and management of scheduling and topology information. It executes centralized scheduling algorithm, sends the scheduling table to each node, as well as manages the sensing tasks of each device. Sensor nodes complete the assigned tasks and sends the sensed data. Furthermore, to prevent scheduling error due to packet loss, a schedule inspection mechanism is implemented to verify the correctness of the schedule table. In addition, when network topology changes, the system will act to generate a new schedule table based on the changed topology for ensuring the proper operation of the system. To enhance the system performance of such system, we further propose dynamic bandwidth allocation and distributed scheduling mechanisms. The developed distributed scheduling mechanism enables each individual sensor node to build, maintain and manage the dedicated link bandwidth with its parent and children nodes based on locally observed information by exchanging the Add/Delete commands via two processes. The first process, termed as the schedule initialization process, allows each sensor node pair to identify the available idle slots to allocate the basic dedicated transmission bandwidth. The second process, termed as the schedule adjustment process, enables each sensor node pair to adjust their allocated bandwidth dynamically according to the measured traffic loading. Such technology can sufficiently satisfy the dynamic bandwidth requirement in the frequently changing environments. Last but not least, we propose a packet retransmission scheme to enhance the system performance of the centralized scheduling algorithm when the packet delivery rate (PDR) is low. We propose a multi-frame retransmission mechanism to allow every single network node to resend each packet for at least the predefined number of times. The multi frame architecture is built according to the number of layers of the network topology. Performance results via simulation reveal that such retransmission scheme is able to provide sufficient high transmission reliability while maintaining low packet transmission latency. Therefore, the QoS requirement of IIoT can be achieved.Keywords: IEEE 802.15.4e, industrial internet of things (IIOT), scheduling mechanisms, wireless sensor networks (WSN)
Procedia PDF Downloads 161489 Estimation of Soil Nutrient Content Using Google Earth and Pleiades Satellite Imagery for Small Farms
Authors: Lucas Barbosa Da Silva, Jun Okamoto Jr.
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Precision Agriculture has long being benefited from crop fields’ aerial imagery. This important tool has allowed identifying patterns in crop fields, generating useful information to the production management. Reflectance intensity data in different ranges from the electromagnetic spectrum may indicate presence or absence of nutrients in the soil of an area. Different relations between the different light bands may generate even more detailed information. The knowledge of the nutrients content in the soil or in the crop during its growth is a valuable asset to the farmer that seeks to optimize its yield. However, small farmers in Brazil often lack the resources to access this kind information, and, even when they do, it is not presented in a comprehensive and/or objective way. So, the challenges of implementing this technology ranges from the sampling of the imagery, using aerial platforms, building of a mosaic with the images to cover the entire crop field, extracting the reflectance information from it and analyzing its relationship with the parameters of interest, to the display of the results in a manner that the farmer may take the necessary decisions more objectively. In this work, it’s proposed an analysis of soil nutrient contents based on image processing of satellite imagery and comparing its outtakes with commercial laboratory’s chemical analysis. Also, sources of satellite imagery are compared, to assess the feasibility of using Google Earth data in this application, and the impacts of doing so, versus the application of imagery from satellites like Landsat-8 and Pleiades. Furthermore, an algorithm for building mosaics is implemented using Google Earth imagery and finally, the possibility of using unmanned aerial vehicles is analyzed. From the data obtained, some soil parameters are estimated, namely, the content of Potassium, Phosphorus, Boron, Manganese, among others. The suitability of Google Earth Imagery for this application is verified within a reasonable margin, when compared to Pleiades Satellite imagery and to the current commercial model. It is also verified that the mosaic construction method has little or no influence on the estimation results. Variability maps are created over the covered area and the impacts of the image resolution and sample time frame are discussed, allowing easy assessments of the results. The final results show that easy and cheaper remote sensing and analysis methods are possible and feasible alternatives for the small farmer, with little access to technological and/or financial resources, to make more accurate decisions about soil nutrient management.Keywords: remote sensing, precision agriculture, mosaic, soil, nutrient content, satellite imagery, aerial imagery
Procedia PDF Downloads 175488 The Influence of Atmospheric Air on the Health of the Population Living in Oil and Gas Production Area in Aktobe Region, Kazakhstan
Authors: Perizat Aitmaganbet, Kerbez Kimatova, Gulmira Umarova
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As a result of medical check-up conducted in the framework of this research study an evaluation of the health status of the population living in the oil-producing regions, namely Sarkul and Kenkiyak villages in Aktobe was examined. With the help of the Spearman correlation, the connection between the level of hazard chemical elements in the atmosphere and the health of population living in the regions of oil and gas industry was estimated. Background & Objective. The oil and gas resource-extraction industries play an important role in improving the economic conditions of the Republic of Kazakhstan, especially for the oil-producing administrative regions. However, environmental problems may adversely affect the health of people living in that area. Thus, the aim of the study is to evaluate the exposure to negative environmental factors of the adult population living in Sarkul and Kenkiyak villages, the oil and gas producing areas in the Aktobe region. Methods. After conducting medical check-up among the population of Sarkul and Kenkiyak villages. A single cross-sectional study was conducted. The population consisted of randomly sampled 372 adults (181 males and 191 females). Also, atmospheric air probes were taken to measure the level of hazardous chemical elements in the air. The nonparametric method of the Spearman correlation analysis was performed between the mean concentration of substances exceeding the Maximum Permissible Concentration and the classes of newly diagnosed diseases. Selection and analysis of air samples were carried out according to the developed research protocol; the qualitative-quantitative analysis was carried out on the Gas analyzer HANK-4 apparatus. Findings. The medical examination of the population identified the following diseases: the first two dominant were diseases of the circulatory and digestive systems, in the 3rd place - diseases of the genitourinary system, and the nervous system and diseases of the ear and mastoid process were on the fourth and fifth places. Moreover, significant pollution of atmospheric air by carbon monoxide (MPC-5,0 mg/m3), benzapyrene (MPC-1mg/m3), dust (MPC-0,5 mg/m3) and phenol (МРС-0,035mg/m3) were identified in places. Correlation dependencies between these pollutants of air and the diseases of the population were established, as a result of diseases of the circulatory system (r = 0,7), ear and mastoid process (r = 0,7), nervous system (r = 0,6) and digestive organs(r = 0,6 ); between the concentration of carbon monoxide and diseases of the circulatory system (r = 0.6), the digestive system(r = 0.6), the genitourinary system (r = 0.6) and the musculoskeletal system; between nitric oxide and diseases of the digestive system (r = 0,7) and the circulatory system (r = 0,6); between benzopyrene and diseases of the digestive system (r = 0,6), the genitourinary system (r = 0,6) and the nervous system (r = 0,4). Conclusion. The positive correlation was found between air pollution and the health of the population living in Sarkul and Kenkiyak villages. To enhance the reliability of the results we are going to continue this study further.Keywords: atmospheric air, chemical substances, oil and gas, public health
Procedia PDF Downloads 115487 The Comparison of Bird’s Population between Naturally Regenerated Acacia Forest with Adjacent Secondary Indigenous Forest in Universiti Malaysia Sabah
Authors: Jephte Sompud, Emily A. Gilbert, Andy Russel Mojiol, Cynthia B. Sompud, Alim Biun
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Naturally regenerated acacia forest and secondary indigenous forest forms some of the urban forests in Sabah. Naturally regenerated acacia trees are usually seen along the road that exists as forest islands. Acacia tree is not an indigenous tree species in Sabah that was introduced in the 1960’s as fire breakers that eventually became one of the preferred trees for forest plantation for paper and pulp production. Due to its adaptability to survive even in impoverished soils and poor-irrigated land, this species has rapidly spread throughout Sabah through natural regeneration. Currently, there is a lack of study to investigate the bird population in the naturally regenerated acacia forest. This study is important because it shed some light on the role of naturally regenerated acacia forest on bird’s population, as bird is known to be a good bioindicator forest health. The aim of this study was to document the bird’s population in naturally regenerated acacia forest with that adjacent secondary indigenous forest. The study site for this study was at Universiti Malaysia Sabah (UMS) Campus. Two forest types in the campus were chosen as a study site, of which were naturally regenerated Acacia Forest and adjacent secondary indigenous forest, located at the UMS Hill. A total of 21 sampling days were conducted in each of the forest types. The method used during this study was solely mist nets with three pockets. Whenever a bird is caught, it is extracted from the net to be identified and measurements were recorded in a standard data sheet. Mist netting was conducted from 6 morning until 5 evening. This study was conducted between February to August 2014. Birds that were caught were ring banded to initiate a long-term study on the understory bird’s population in the Campus The data was analyzed using descriptive analysis, diversity indices, and t-test. The bird population diversity at naturally regenerated Acacia forest with those at the secondary indigenous forest was calculated using two common indices, of which were Shannon-Wiener and Simpson diversity index. There were 18 families with 33 species that were recorded from both sites. The number of species recorded at the naturally regenerated acacia forest was 26 species while at the secondary indigenous forest were 19 species. The Shannon diversity index for Naturally Regenerated Acacia Forest and secondary indigenous forests were 2.87 and 2.46. The results show that there was very significantly higher species diversity at the Naturally Regenerated Acacia Forest as opposed to the secondary indigenous forest (p<0.001). This suggests that Naturally Regenerated Acacia forest plays an important role in urban bird conservation. It is recommended that Naturally Regenerated Acacia Forests should be considered as an established urban forest conservation area as they do play a role in biodiversity conservation. More future studies in Naturally Regenerated Acacia Forest should be encouraged to determine the status and value of biodiversity conservation of this ecosystem.Keywords: naturally regenerated acacia forest, bird population diversity, Universiti Malaysia Sabah, biodiversity conservation
Procedia PDF Downloads 427486 Geographic Origin Determination of Greek Rice (Oryza Sativa L.) Using Stable Isotopic Ratio Analysis
Authors: Anna-Akrivi Thomatou, Anastasios Zotos, Eleni C. Mazarakioti, Efthimios Kokkotos, Achilleas Kontogeorgos, Athanasios Ladavos, Angelos Patakas
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It is well known that accurate determination of geographic origin to confront mislabeling and adulteration of foods is considered as a critical issue worldwide not only for the consumers, but also for producers and industries. Among agricultural products, rice (Oryza sativa L.) is the world’s third largest crop, providing food for more than half of the world’s population. Consequently, the quality and safety of rice products play an important role in people’s life and health. Despite the fact that rice is predominantly produced in Asian countries, rice cultivation in Greece is of significant importance, contributing to national agricultural sector income. More than 25,000 acres are cultivated in Greece, while rice exports to other countries consist the 0,5% of the global rice trade. Although several techniques are available in order to provide information about the geographical origin of rice, little data exist regarding the ability of these methodologies to discriminate rice production from Greece. Thus, the aim of this study is the comparative evaluation of stable isotope ratio methodology regarding its discriminative ability for geographical origin determination of rice samples produced in Greece compared to those from three other Asian countries namely Korea, China and Philippines. In total eighty (80) samples were collected from selected fields of Central Macedonia (Greece), during October of 2021. The light element (C, N, S) isotope ratios were measured using Isotope Ratio Mass Spectrometry (IRMS) and the results obtained were analyzed using chemometric techniques, including principal components analysis (PCA). Results indicated that the 𝜹 15N and 𝜹 34S values of rice produced in Greece were more markedly influenced by geographical origin compared to the 𝜹 13C. In particular, 𝜹 34S values in rice originating from Greece was -1.98 ± 1.71 compared to 2.10 ± 1.87, 4.41 ± 0.88 and 9.02 ± 0.75 for Korea, China and Philippines respectively. Among stable isotope ratios studied, values of 𝜹 34S seem to be the more appropriate isotope marker to discriminate rice geographic origin between the studied areas. These results imply the significant capability of stable isotope ratio methodology for effective geographical origin discrimination of rice, providing a valuable insight into the control of improper or fraudulent labeling. Acknowledgement: This research has been financed by the Public Investment Programme/General Secretariat for Research and Innovation, under the call “YPOERGO 3, code 2018SE01300000: project title: ‘Elaboration and implementation of methodology for authenticity and geographical origin assessment of agricultural products.Keywords: geographical origin, authenticity, rice, isotope ratio mass spectrometry
Procedia PDF Downloads 90485 Anti-Apoptotic Effect of Pueraria tuberosa in Rats with Streptozotocin Induced Diabetic Nephropathy
Authors: Rashmi Shukla, Yamini Bhusan Tripathi
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Diabetic nephropathy (DN) is characterized as diabetic kidney disease which involves many pathways e.g. hyperactivated protein kinase c (PKC), polyol pathway, excess production of advanced glycation end product (AGEs) & free radical accumulation etc. All of them results to hypoxia followed by apoptosis of podocytes, glomerulosclerosis, extracellular matrix (ECM) accumulation and fibrosis resulting to irreversible changes in kidney. This is continuously rising worldwide and there are not enough specific drugs, to retard its progress. Due to increasing side effects of allopathic drugs, interest in herbal remedies is growing. Earlier, we have reported that PTY-2 (a phytomedicine, derived from Pueraria tuberosa Linn.) inhibits the accumulation of extracellular matrix (ECM) through activation of MMP-9. Present study exhibited the therapeutic potential of Pueraria tuberosa in the prevention of podocytes apoptosis and modulation of nephrin expression in streptozotocin (STZ) induced DN rats. DN rats were produced by maintaining persistent hyperglycemia for 8 weeks by intra-peritoneal injection of 55 mg/kg streptozotocin (STZ). These rats were randomly divided in 2 groups, i.e. DN control, and DN+ water extract of Pueraria tuberosa (PTW). One group of age-matched normal rats served as non-diabetic control (group-1), The STZ induced DN rats (group-2) and DN+PTW treated rats (group-3). The PTW was orally administered (0.3g/kg) daily to group-2 rats and drug vector (1 ml of 10% tween 20) in control rats. The treatments were continued for 20 days and blood and urine samples were collected. Rats were then sacrificed to investigate the expression Bcl2, Bax and nephroprotective protein i.e. nephrin in kidney glomerulus. The effect of PTW was evaluated, we have found that the PTW significantly(p < .001) reversed the raised serum urea, serum creatinine, urine protein and improved the creatinine clearance in STZ induce diabetic nephropathy in rats and also significantly(p < .001) prevented the rise in urine albumin excretion. The Western blot analysis of kidney tissue homogenate showed increased expression of Bcl2 in PTW treated rats. The RT-PCR showed the increased expression and accumulation of nephrin mRNA. The confocal photomicrographs also supported the reduction of Bax and a simultaneous increase in Bcl2 and nephrin in glomerular podocytes. Hence, our finding suggests that the nephroprotective role of PTW is mediated via restoration of nephrin thus prevents the podocytes apoptosis and ameliorates diabetic nephropathy. The clinical trial of PTW would prove to be a potential food supplement/ drug of alternative medicine for patients with diabetic nephropathy in early stage.Keywords: Pueraria tuberosa, diabetic nephropathy, anti-apoptosis, nephrin
Procedia PDF Downloads 217484 Machine Learning Techniques for Estimating Ground Motion Parameters
Authors: Farid Khosravikia, Patricia Clayton
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The main objective of this study is to evaluate the advantages and disadvantages of various machine learning techniques in forecasting ground-motion intensity measures given source characteristics, source-to-site distance, and local site condition. Intensity measures such as peak ground acceleration and velocity (PGA and PGV, respectively) as well as 5% damped elastic pseudospectral accelerations at different periods (PSA), are indicators of the strength of shaking at the ground surface. Estimating these variables for future earthquake events is a key step in seismic hazard assessment and potentially subsequent risk assessment of different types of structures. Typically, linear regression-based models, with pre-defined equations and coefficients, are used in ground motion prediction. However, due to the restrictions of the linear regression methods, such models may not capture more complex nonlinear behaviors that exist in the data. Thus, this study comparatively investigates potential benefits from employing other machine learning techniques as a statistical method in ground motion prediction such as Artificial Neural Network, Random Forest, and Support Vector Machine. The algorithms are adjusted to quantify event-to-event and site-to-site variability of the ground motions by implementing them as random effects in the proposed models to reduce the aleatory uncertainty. All the algorithms are trained using a selected database of 4,528 ground-motions, including 376 seismic events with magnitude 3 to 5.8, recorded over the hypocentral distance range of 4 to 500 km in Oklahoma, Kansas, and Texas since 2005. The main reason of the considered database stems from the recent increase in the seismicity rate of these states attributed to petroleum production and wastewater disposal activities, which necessities further investigation in the ground motion models developed for these states. Accuracy of the models in predicting intensity measures, generalization capability of the models for future data, as well as usability of the models are discussed in the evaluation process. The results indicate the algorithms satisfy some physically sound characteristics such as magnitude scaling distance dependency without requiring pre-defined equations or coefficients. Moreover, it is shown that, when sufficient data is available, all the alternative algorithms tend to provide more accurate estimates compared to the conventional linear regression-based method, and particularly, Random Forest outperforms the other algorithms. However, the conventional method is a better tool when limited data is available.Keywords: artificial neural network, ground-motion models, machine learning, random forest, support vector machine
Procedia PDF Downloads 122483 The Use of Punctuation by Primary School Students Writing Texts Collaboratively: A Franco-Brazilian Comparative Study
Authors: Cristina Felipeto, Catherine Bore, Eduardo Calil
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This work aims to analyze and compare the punctuation marks (PM) in school texts of Brazilian and French students and the comments on these PM made spontaneously by the students during the ongoing text. Assuming textual genetics as an investigative field within a dialogical and enunciative approach, we defined a common methodological design in two 1st year classrooms (7 years old) of the primary school, one classroom in Brazil (Maceio) and the other one in France (Paris). Through a multimodal capture system of writing processes in real time and space (Ramos System), we recorded the collaborative writing proposal in dyads in each of the classrooms. This system preserves the classroom’s ecological characteristics and provides a video recording synchronized with dialogues, gestures and facial expressions of the students, the stroke of the pen’s ink on the sheet of paper and the movement of the teacher and students in the classroom. The multimodal register of the writing process allowed access to the text in progress and the comments made by the students on what was being written. In each proposed text production, teachers organized their students in dyads and requested that they should talk, combine and write a fictional narrative. We selected a Dyad of Brazilian students (BD) and another Dyad of French students (FD) and we have filmed 6 proposals for each of the dyads. The proposals were collected during the 2nd Term of 2013 (Brazil) and 2014 (France). In 6 texts written by the BD there were identified 39 PMs and 825 written words (on average, a PM every 23 words): Of these 39 PMs, 27 were highlighted orally and commented by either student. In the texts written by the FD there were identified 48 PMs and 258 written words (on average, 1 PM every 5 words): Of these 48 PM, 39 were commented by the French students. Unlike what the studies on punctuation acquisition point out, the PM that occurred the most were hyphens (BD) and commas (FD). Despite the significant difference between the types and quantities of PM in the written texts, the recognition of the need for writing PM in the text in progress and the comments have some common characteristics: i) the writing of the PM was not anticipated in relation to the text in progress, then they were added after the end of a sentence or after the finished text itself; ii) the need to add punctuation marks in the text came after one of the students had ‘remembered’ that a particular sign was needed; iii) most of the PM inscribed were not related to their linguistic functions, but the graphic-visual feature of the text; iv) the comments justify or explain the PM, indicating metalinguistic reflections made by the students. Our results indicate how the comments of the BD and FD express the dialogic and subjective nature of knowledge acquisition. Our study suggests that the initial learning of PM depends more on its graphic features and interactional conditions than on its linguistic functions.Keywords: collaborative writing, erasure, graphic marks, learning, metalinguistic awareness, textual genesis
Procedia PDF Downloads 162482 Biorefinery as Extension to Sugar Mills: Sustainability and Social Upliftment in the Green Economy
Authors: Asfaw Gezae Daful, Mohsen Alimandagari, Kathleen Haigh, Somayeh Farzad, Eugene Van Rensburg, Johann F. Görgens
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The sugar industry has to 're-invent' itself to ensure long-term economic survival and opportunities for job creation and enhanced community-level impacts, given increasing pressure from fluctuating and low global sugar prices, increasing energy prices and sustainability demands. We propose biorefineries for re-vitalisation of the sugar industry using low value lignocellulosic biomass (sugarcane bagasse, leaves, and tops) annexed to existing sugar mills, producing a spectrum of high value platform chemicals along with biofuel, bioenergy, and electricity. Opportunity is presented for greener products, to mitigate climate change and overcome economic challenges. Xylose from labile hemicellulose remains largely underutilized and the conversion to value-add products a major challenge. Insight is required on pretreatment and/or extraction to optimize production of cellulosic ethanol together with lactic acid, furfural or biopolymers from sugarcane bagasse, leaves, and tops. Experimental conditions for alkaline and pressurized hot water extraction dilute acid and steam explosion pretreatment of sugarcane bagasse and harvest residues were investigated to serve as a basis for developing various process scenarios under a sugarcane biorefinery scheme. Dilute acid and steam explosion pretreatment were optimized for maximum hemicellulose recovery, combined sugar yield and solids digestibility. An optimal range of conditions for alkaline and liquid hot water extraction of hemicellulosic biopolymers, as well as conditions for acceptable enzymatic digestibility of the solid residue, after such extraction was established. Using data from the above, a series of energy efficient biorefinery scenarios are under development and modeled using Aspen Plus® software, to simulate potential factories to better understand the biorefinery processes and estimate the CAPEX and OPEX, environmental impacts, and overall viability. Rigorous and detailed sustainability assessment methodology was formulated to address all pillars of sustainability. This work is ongoing and to date, models have been developed for some of the processes which can ultimately be combined into biorefinery scenarios. This will allow systematic comparison of a series of biorefinery scenarios to assess the potential to reduce negative impacts on and maximize the benefits of social, economic, and environmental factors on a lifecycle basis.Keywords: biomass, biorefinery, green economy, sustainability
Procedia PDF Downloads 514481 Effect of Plant Growth Regulators on in vitro Biosynthesis of Antioxidative Compounds in Callus Culture and Regenerated Plantlets Derived from Taraxacum officinale
Authors: Neha Sahu, Awantika Singh, Brijesh Kumar, K. R. Arya
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Taraxacum officinale Weber or dandelion (Asteraceae) is an important Indian traditional herb used to treat liver detoxification, digestive problems, spleen, hepatic and kidney disorders, etc. The plant is well known to possess important phenolic and flavonoids to serve as a potential source of antioxidative and chemoprotective agents. Biosynthesis of bioactive compounds through in vitro cultures is a requisite for natural resource conservation and to provide an alternative source for pharmaceutical applications. Thus an efficient and reproducible protocol was developed for in vitro biosynthesis of bioactive antioxidative compounds from leaf derived callus and in vitro regenerated cultures of Taraxacum officinale using MS media fortified with various combinations of auxins and cytokinins. MS media containing 0.25 mg/l 2, 4-D (2, 4-Dichloro phenoxyacetic acid) with 0.05 mg/l 2-iP [N6-(2-Isopentenyl adenine)] was found as an effective combination for the establishment of callus with 92 % callus induction frequency. Moreover, 2.5 mg/l NAA (α-Naphthalene acetic acid) with 0.5 mg/l BAP (6-Benzyl aminopurine) and 1.5 mg/l NAA showed the optimal response for in vitro plant regeneration with 80 % regeneration frequency and rooting respectively. In vitro regenerated plantlets were further transferred to soil and acclimatized. Quantitative variability of accumulated bioactive compounds in cultures (in vitro callus, plantlets and acclimatized) were determined through UPLC-MS/MS (ultra-performance liquid chromatography-triple quadrupole-linear ion trap mass spectrometry) and compared with wild plants. The phytochemical determination of in vitro and wild grown samples showed the accumulation of 6 compounds. In in vitro callus cultures and regenerated plantlets, two major antioxidative compounds i.e. chlorogenic acid (14950.0 µg/g and 4086.67 µg/g) and umbelliferone (10400.00 µg/g and 2541.67 µg/g) were found respectively. Scopoletin was found to be highest in vitro regenerated plants (83.11 µg/g) as compared to wild plants (52.75 µg/g). Notably, scopoletin is not detected in callus and acclimatized plants, but quinic acid (6433.33 µg/g) and protocatechuic acid (92.33 µg/g) were accumulated at the highest level in acclimatized plants as compared to other samples. Wild grown plants contained highest content (948.33 µg/g) of flavonoid glycoside i.e. luteolin-7-O-glucoside. Our data suggests that in vitro callus and regenerated plants biosynthesized higher content of antioxidative compounds in controlled conditions when compared to wild grown plants. These standardized cultural conditions may be explored as a sustainable source of plant materials for enhanced production and adequate supply of oxidative polyphenols.Keywords: anti-oxidative compounds, in vitro cultures, Taraxacum officinale, UPLC-MS/MS
Procedia PDF Downloads 201480 A New Approach for Preparation of Super Absorbent Polymers: In-Situ Surface Cross-Linking
Authors: Reyhan Özdoğan, Mithat Çelebi, Özgür Ceylan, Mehmet Arif Kaya
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Super absorbent polymers (SAPs) are defined as materials that can absorb huge amount of water or aqueous solution in comparison to their own mass and retain in their lightly cross-linked structure. SAPs were produced from water soluble monomers via polymerization subsequently controlled crosslinking. SAPs are generally used for water absorbing applications such as baby diapers, patient or elder pads and other hygienic product industries. Crosslinking density (CD) of SAP structure is an essential factor for water absortion capacity (WAC). Low internal CD leads to high WAC values and vice versa. However, SAPs have low CD and high swelling capacities and tend to disintegrate when pressure is applied upon them, so SAPs under load cannot absorb liquids effectively. In order to prevent this undesired situation and to obtain suitable SAP structures having high swelling capacity and ability to work under load, surface crosslinking can be the answer. In industry, these superabsorbent gels are mostly produced via solution polymerization and then they need to be dried, grinded, sized, post polymerized and finally surface croslinked (involves spraying of a crosslinking solution onto dried and grinded SAP particles, and then curing by heat). It can easily be seen that these steps are time consuming and should be handled carefully for the desired final product. If we could synthesize desired final SAPs using less processes it will help reducing time and production costs which are very important for any industries. In this study, synthesis of SAPs were achieved successfully by inverse suspension (Pickering type) polymerization and subsequently in-situ surface cross-linking via using proper surfactants in high boiling point solvents. Our one-pot synthesis of surface cross-linked SAPs invovles only one-step for preparation, thus it can be said that this technique exhibits more preferable characteristic for the industry in comparison to conventional methods due to its one-step easy process. Effects of different surface crosslinking agents onto properties of poly(acrylic acid-co-sodium acrylate) based SAPs are investigated. Surface crosslink degrees are evaluated by swelling under load (SUL) test. It was determined water absorption capacities of obtained SAPs decrease with the increasing surface crosslink density while their mechanic properties are improved.Keywords: inverse suspension polymerization, polyacrylic acid, super absorbent polymers (SAPs), surface crosslinking, sodium polyacrylate
Procedia PDF Downloads 323479 Solid State Drive End to End Reliability Prediction, Characterization and Control
Authors: Mohd Azman Abdul Latif, Erwan Basiron
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A flaw or drift from expected operational performance in one component (NAND, PMIC, controller, DRAM, etc.) may affect the reliability of the entire Solid State Drive (SSD) system. Therefore, it is important to ensure the required quality of each individual component through qualification testing specified using standards or user requirements. Qualification testing is time-consuming and comes at a substantial cost for product manufacturers. A highly technical team, from all the eminent stakeholders is embarking on reliability prediction from beginning of new product development, identify critical to reliability parameters, perform full-blown characterization to embed margin into product reliability and establish control to ensure the product reliability is sustainable in the mass production. The paper will discuss a comprehensive development framework, comprehending SSD end to end from design to assembly, in-line inspection, in-line testing and will be able to predict and to validate the product reliability at the early stage of new product development. During the design stage, the SSD will go through intense reliability margin investigation with focus on assembly process attributes, process equipment control, in-process metrology and also comprehending forward looking product roadmap. Once these pillars are completed, the next step is to perform process characterization and build up reliability prediction modeling. Next, for the design validation process, the reliability prediction specifically solder joint simulator will be established. The SSD will be stratified into Non-Operating and Operating tests with focus on solder joint reliability and connectivity/component latent failures by prevention through design intervention and containment through Temperature Cycle Test (TCT). Some of the SSDs will be subjected to the physical solder joint analysis called Dye and Pry (DP) and Cross Section analysis. The result will be feedbacked to the simulation team for any corrective actions required to further improve the design. Once the SSD is validated and is proven working, it will be subjected to implementation of the monitor phase whereby Design for Assembly (DFA) rules will be updated. At this stage, the design change, process and equipment parameters are in control. Predictable product reliability at early product development will enable on-time sample qualification delivery to customer and will optimize product development validation, effective development resource and will avoid forced late investment to bandage the end-of-life product failures. Understanding the critical to reliability parameters earlier will allow focus on increasing the product margin that will increase customer confidence to product reliability.Keywords: e2e reliability prediction, SSD, TCT, solder joint reliability, NUDD, connectivity issues, qualifications, characterization and control
Procedia PDF Downloads 174478 Evaluation of Antimicrobial and Anti-Inflammatory Activity of Doani Sidr Honey and Madecassoside against Propionibacterium Acnes
Authors: Hana Al-Baghaoi, Kumar Shiva Gubbiyappa, Mayuren Candasamy, Kiruthiga Perumal Vijayaraman
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Acne is a chronic inflammatory disease of the sebaceous glands characterized by areas of skin with seborrhea, comedones, papules, pustules, nodules, and possibly scarring. Propionibacterium acnes (P. acnes), plays a key role in the pathogenesis of acne. Their colonization and proliferation trigger the host’s inflammatory response leading to the production of pro-inflammatory cytokines such as interleukin-8 (IL-8) and tumour necrosis factor-α (TNF-α). The usage of honey and natural compounds to treat skin ailments has strong support in the current trend of drug discovery. The present study was carried out evaluate antimicrobial and anti-inflammatory potential of Doani Sidr honey and its fractions against P. acnes and to screen madecassoside alone and in combination with fractions of honey. The broth dilution method was used to assess the antibacterial activity. Also, ultra structural changes in cell morphology were studied before and after exposure to Sidr honey using transmission electron microscopy (TEM). The three non-toxic concentrations of the samples were investigated for suppression of cytokines IL 8 and TNF α by testing the cell supernatants in the co-culture of the human peripheral blood mononuclear cells (hPBMCs) heat killed P. acnes using enzyme immunoassay kits (ELISA). Results obtained was evaluated by statistical analysis using Graph Pad Prism 5 software. The Doani Sidr honey and polysaccharide fractions were able to inhibit the growth of P. acnes with a noteworthy minimum inhibitory concentration (MIC) value of 18% (w/v) and 29% (w/v), respectively. The proximity of MIC and MBC values indicates that Doani Sidr honey had bactericidal effect against P. acnes which is confirmed by TEM analysis. TEM images of P. acnes after treatment with Doani Sidr honey showed completely physical membrane damage and lysis of cells; whereas non honey treated cells (control) did not show any damage. In addition, Doani Sidr honey and its fractions significantly inhibited (> 90%) of secretion of pro-inflammatory cytokines like TNF α and IL 8 by hPBMCs pretreated with heat-killed P. acnes. However, no significant inhibition was detected for madecassoside at its highest concentration tested. Our results suggested that Doani Sidr honey possesses both antimicrobial and anti-inflammatory effects against P. acnes and can possibly be used as therapeutic agents for acne. Furthermore, polysaccharide fraction derived from Doani Sidr honey showed potent inhibitory effect toward P. acnes. Hence, we hypothesize that fraction prepared from Sidr honey might be contributing to the antimicrobial and anti-inflammatory activity. Therefore, this polysaccharide fraction of Doani Sidr honey needs to be further explored and characterized for various phytochemicals which are contributing to antimicrobial and anti-inflammatory properties.Keywords: Doani sidr honey, Propionibacterium acnes, IL-8, TNF alpha
Procedia PDF Downloads 400477 Cytotoxic Effect of Biologically Transformed Propolis on HCT-116 Human Colon Cancer Cells
Authors: N. Selvi Gunel, L. M. Oktay, H. Memmedov, B. Durmaz, H. Kalkan Yildirim, E. Yildirim Sozmen
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Object: Propolis which consists of compounds that are accepted as antioxidant, antimicrobial, antiseptic, antibacterial, anti-inflammatory, anti-mutagenic, immune-modulator and cytotoxic, is frequently used in current therapeutic applications. However, some of them result in allergic side effects, causing consumption to be restricted. Previously our group has succeeded in producing a new biotechnological product which was less allergenic. In this study, we purpose to optimize production conditions of this biologically-transformed propolis and determine the cytotoxic effects of obtained new products on colon cancer cell line (HCT-116). Method: Firstly, solid propolis samples were dissolved in water after weighing, grinding and sizing (sieve-35mesh) and applied 40 kHz/10 min ultrasonication. Samples were prepared according to inoculation with Lactobacillus plantarum in two different proportions (2.5% and 3.5%). Chromatographic analyzes of propolis were performed by UPLC-MS/MS (Waters, Milford, MA) system. Results were analysed by UPLC-MS/MS system MassLynx™ 4.1 software. HCT-116 cells were treated with propolis examples at 25-1000 µg/ml concentrations and cytotoxicity were measured by using WST-8 assay at 24, 48, and 72 hours. Samples with biological transformation were compared with the non-transformed control group samples. Our experiment groups were formed as follows: untreated (group 1), propolis dissolved in water ultrasonicated at 40 kHz/10 min (group 2), propolis dissolved in water ultrasonicated at 40 kHz/10 min and inoculated 2.5% L. plantarum L1 strain (group 3), propolis dissolved in water ultrasonicated at 40 kHz/10 min and inoculated 3.5% L. plantarum L3 strain (group 4). Obtained data were calculated with Graphpad Software V5 and analyzed by two-way ANOVA test followed by Bonferroni test. Result: As a result of our study, the cytotoxic effect of propolis samples on HCT-116 cells was evaluated. There was a 7.21 fold increase in group 3 compared to group 2 in the concentration of 1000 µg/ml, and it was a 6.66 fold increase in group 3 compared to group 1 at the end of 24 hours. At the end of 48 hours, in the concentration of 500 µg/ml, it was determined 4.7 fold increase in group 4 compared to group 3. At the same time, in the concentration of 750 µg/ml it was determined 2.01 fold increase in group 4 compared to group 3 and in the same concentration, it was determined 3.1 fold increase in group 4 compared to group 2. Also, at the 72 hours, in the concentration of 750 µg/ml, it was determined 2.42 fold increase in group 3 according to group 2 and in the same time, in the concentration of 1000 µg/ml, it was determined 2.13 fold increase in group 4 according to group 2. According to cytotoxicity results, the group which were ultrasonicated at 40 kHz/10min and inoculated 3.5% L. plantarum L3-strain had a higher cytotoxic effect. Conclusion: It is known that bioavailability of propolis is halved in six months. The data obtained from our results indicated that biologically-transformed propolis had more cytotoxic effect than non-transformed group on colon cancer cells. Consequently, we suggested that L. plantarum-transformation provides both reduction of allergenicity and extension of bioavailability period by enhancing healthful polyphenols.Keywords: bio-transformation, propolis, colon cancer, cytotoxicity
Procedia PDF Downloads 140476 Enhancing Algal Bacterial Photobioreactor Efficiency: Nutrient Removal and Cost Analysis Comparison for Light Source Optimization
Authors: Shahrukh Ahmad, Purnendu Bose
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Algal-Bacterial photobioreactors (ABPBRs) have emerged as a promising technology for sustainable biomass production and wastewater treatment. Nutrient removal is seldom done in sewage treatment plants and large volumes of wastewater which still have nutrients are being discharged and that can lead to eutrophication. That is why ABPBR plays a vital role in wastewater treatment. However, improving the efficiency of ABPBR remains a significant challenge. This study aims to enhance ABPBR efficiency by focusing on two key aspects: nutrient removal and cost-effective optimization of the light source. By integrating nutrient removal and cost analysis for light source optimization, this study proposes practical strategies for improving ABPBR efficiency. To reduce organic carbon and convert ammonia to nitrates, domestic wastewater from a 130 MLD sewage treatment plant (STP) was aerated with a hydraulic retention time (HRT) of 2 days. The treated supernatant had an approximate nitrate and phosphate values of 16 ppm as N and 6 ppm as P, respectively. This supernatant was then fed into the ABPBR, and the removal of nutrients (nitrate as N and phosphate as P) was observed using different colored LED bulbs, namely white, blue, red, yellow, and green. The ABPBR operated with a 9-hour light and 3-hour dark cycle, using only one color of bulbs per cycle. The study found that the white LED bulb, with a photosynthetic photon flux density (PPFD) value of 82.61 µmol.m-2 .sec-1 , exhibited the highest removal efficiency. It achieved a removal rate of 91.56% for nitrate and 86.44% for phosphate, surpassing the other colored bulbs. Conversely, the green LED bulbs showed the lowest removal efficiencies, with 58.08% for nitrate and 47.48% for phosphate at an HRT of 5 days. The quantum PAR (Photosynthetic Active Radiation) meter measured the photosynthetic photon flux density for each colored bulb setting inside the photo chamber, confirming that white LED bulbs operated at a wider wavelength band than the others. Furthermore, a cost comparison was conducted for each colored bulb setting. The study revealed that the white LED bulb had the lowest average cost (Indian Rupee)/light intensity (µmol.m-2 .sec-1 ) value at 19.40, while the green LED bulbs had the highest average cost (INR)/light intensity (µmol.m-2 .sec-1 ) value at 115.11. Based on these comparative tests, it was concluded that the white LED bulbs were the most efficient and costeffective light source for an algal photobioreactor. They can be effectively utilized for nutrient removal from secondary treated wastewater which helps in improving the overall wastewater quality before it is discharged back into the environment.Keywords: algal bacterial photobioreactor, domestic wastewater, nutrient removal, led bulbs
Procedia PDF Downloads 79475 Examining Smallholder Farmers’ Perceptions of Climate Change and Barriers to Strategic Adaptation in Todee District, Liberia
Authors: Joe Dorbor Wuokolo
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Thousands of smallholder farmers in Todee District, Montserrado county, are currently vulnerable to the negative impact of climate change. The district, which is the agricultural hot spot for the county, is faced with unfavorable changes in the daily temperature due to climate change. Farmers in the district have observed a dramatic change in the ratio of rainfall to sunshine, which has caused a chilling effect on their crop yields. However, there is a lack of documentation regarding how farmers perceive and respond to these changes and challenges. A study was conducted in the region to examine the perceptions of smallholder farmers regarding the negative impact of climate change, the adaptation strategies practice, and the barriers that hinder the process of advancing adaptation strategy. On purpose, a sample of 41 respondents from five towns was selected, including five town chiefs, five youth leaders, five women leaders, and sixteen community members. Women and youth leaders were specifically chosen to provide gender balance and enhance the quality of the investigation. Additionally, to validate the barriers farmers face during adaptation to climate change, this study interviewed eight experts from local and international organizations and government ministries and agencies involved in climate change and agricultural programs on what they perceived as the major barrier in both local and national level that impede farmers adaptation to climate change impact. SPSS was used to code the data, and descriptive statistics were used to analyze the data. The weighted average index (WAI) was used to rank adaptation strategies and the perceived importance of adaptation practices among farmers. On a scale from 0 to 3, 0 indicates the least important technique, and 3 indicates the most effective technique. In addition, the Problem Confrontation Index (PCI) was used to rank the barriers that prevented farmers from implementing adaptation measures. According to the findings, approximately 60% of all respondents considered the use of irrigation systems to be the most effective adaptation strategy, with drought-resistant varieties making up 30% of the total. Additionally, 80% of respondents placed a high value on drought-resistant varieties, while 63% percent placed it on irrigation practices. In addition, 78% of farmers ranked and indicated that unpredictability of the weather is the most significant barrier to their adaptation strategies, followed by the high cost of farm inputs and lack of access to financing facilities. 80% of respondents believe that the long-term changes in precipitation (rainfall) and temperature (hotness) are accelerating. This suggests that decision-makers should adopt policies and increase the capacity of smallholder farmers to adapt to the negative impact of climate change in order to ensure sustainable food production.Keywords: adaptation strategies, climate change, farmers’ perception, smallholder farmers
Procedia PDF Downloads 82474 Distinguishing Substance from Spectacle in Violent Extremist Propaganda through Frame Analysis
Authors: John Hardy
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Over the last decade, the world has witnessed an unprecedented rise in the quality and availability of violent extremist propaganda. This phenomenon has been fueled primarily by three interrelated trends: rapid adoption of online content mediums by creators of violent extremist propaganda, increasing sophistication of violent extremist content production, and greater coordination of content and action across violent extremist organizations. In particular, the self-styled ‘Islamic State’ attracted widespread attention from its supporters and detractors alike by mixing shocking video and imagery content in with substantive ideological and political content. Although this practice was widely condemned for its brutality, it proved to be effective at engaging with a variety of international audiences and encouraging potential supporters to seek further information. The reasons for the noteworthy success of this kind of shock-value propaganda content remain unclear, despite many governments’ attempts to produce counterpropaganda. This study examines violent extremist propaganda distributed by five terrorist organizations between 2010 and 2016, using material released by the Al Hayat Media Center of the Islamic State, Boko Haram, Al Qaeda, Al Qaeda in the Arabian Peninsula, and Al Qaeda in the Islamic Maghreb. The time period covers all issues of the infamous publications Inspire and Dabiq, as well as the most shocking video content released by the Islamic State and its affiliates. The study uses frame analysis to distinguish thematic from symbolic content in violent extremist propaganda by contrasting the ways that substantive ideology issues were framed against the use of symbols and violence to garner attention and to stylize propaganda. The results demonstrate that thematic content focuses significantly on diagnostic frames, which explain violent extremist groups’ causes, and prognostic frames, which propose solutions to addressing or rectifying the cause shared by groups and their sympathizers. Conversely, symbolic violence is primarily stylistic and rarely linked to thematic issues or motivational framing. Frame analysis provides a useful preliminary tool in disentangling substantive ideological and political content from stylistic brutality in violent extremist propaganda. This provides governments and researchers a method for better understanding the framing and content used to design narratives and propaganda materials used to promote violent extremism around the world. Increased capacity to process and understand violent extremist narratives will further enable governments and non-governmental organizations to develop effective counternarratives which promote non-violent solutions to extremists’ grievances.Keywords: countering violent extremism, counternarratives, frame analysis, propaganda, terrorism, violent extremism
Procedia PDF Downloads 173473 The Impacts of Export in Stimulating Economic Growth in Ethiopia: ARDL Model Analysis
Authors: Natnael Debalklie Teshome
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The purpose of the study was to empirically investigate the impacts of export performance and its volatility on economic growth in the Ethiopian economy. To do so, time-series data of the sample period from 1974/75 – 2017/18 were collected from databases and annual reports of IMF, WB, NBE, MoFED, UNCTD, and EEA. The extended Cobb-Douglas production function of the neoclassical growth model framed under the endogenous growth theory was used to consider both the performance and instability aspects of export. First, the unit root test was conducted using ADF and PP tests, and data were found in stationery with a mix of I(0) and I(1). Then, the bound test and Wald test were employed, and results showed that there exists long-run co-integration among study variables. All the diagnostic test results also reveal that the model fulfills the criteria of the best-fitted model. Therefore, the ARDL model and VECM were applied to estimate the long-run and short-run parameters, while the Granger causality test was used to test the causality between study variables. The empirical findings of the study reveal that only export and coefficient of variation had significant positive and negative impacts on RGDP in the long run, respectively, while other variables were found to have an insignificant impact on the economic growth of Ethiopia. In the short run, except for gross capital formation and coefficients of variation, which have a highly significant positive impact, all other variables have a strongly significant negative impact on RGDP. This shows exports had a strong, significant impact in both the short-run and long-run periods. However, its positive and statistically significant impact is observed only in the long run. Similarly, there was a highly significant export fluctuation in both periods, while significant commodity concentration (CCI) was observed only in the short run. Moreover, the Granger causality test reveals that unidirectional causality running from export performance to RGDP exists in the long run and from both export and RGDP to CCI in the short run. Therefore, the export-led growth strategy should be sustained and strengthened. In addition, boosting the industrial sector is vital to bring structural transformation. Hence, the government has to give different incentive schemes and supportive measures to exporters to extract the spillover effects of exports. Greater emphasis on price-oriented diversification and specialization on major primary products that the country has a comparative advantage should also be given to reduce value-based instability in the export earnings of the country. The government should also strive to increase capital formation and human capital development via enhancing investments in technology and quality of education to accelerate the economic growth of the country.Keywords: export, economic growth, export diversification, instability, co-integration, granger causality, Ethiopian economy
Procedia PDF Downloads 77472 Genetic Variations of Two Casein Genes among Maghrabi Camels Reared in Egypt
Authors: Othman E. Othman, Amira M. Nowier, Medhat El-Denary
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Camels play an important socio-economic role within the pastoral and agricultural system in the dry and semidry zones of Asia and Africa. Camels are economically important animals in Egypt where they are dual purpose animals (meat and milk). The analysis of chemical composition of camel milk showed that the total protein contents ranged from 2.4% to 5.3% and it is divided into casein and whey proteins. The casein fraction constitutes 52% to 89% of total camel milk protein and it divided into 4 fractions namely αs1, αs2, β and κ-caseins which are encoded by four tightly genes. In spite of the important role of casein genes and the effects of their genetic polymorphisms on quantitative traits and technological properties of milk, the studies for the detection of genetic polymorphism of camel milk genes are still limited. Due to this fact, this work focused - using PCR-RFP and sequencing analysis - on the identification of genetic polymorphisms and SNPs of two casein genes in Maghrabi camel breed which is a dual purpose camel breed in Egypt. The amplified fragments at 488-bp of the camel κ-CN gene were digested with AluI endonuclease. The results showed the appearance of three different genotypes in the tested animals; CC with three digested fragments at 203-, 127- and 120-bp, TT with three digested fragments at 203-, 158- and 127-bp and CT with four digested fragments at 203-, 158-, 127- and 120-bp. The frequencies of three detected genotypes were 11.0% for CC, 48.0% for TT and 41.0% for CT genotypes. The sequencing analysis of the two different alleles declared the presence of a single nucleotide polymorphism (C→T) at position 121 in the amplified fragments which is responsible for the destruction of a restriction site (AG/CT) in allele T and resulted in the presence of two different alleles C and T in tested animals. The nucleotide sequences of κ-CN alleles C and T were submitted to GenBank with the accession numbers; KU055605 and KU055606, respectively. The primers used in this study amplified 942-bp fragments spanning from exon 4 to exon 6 of camel αS1-Casein gene. The amplified fragments were digested with two different restriction enzymes; SmlI and AluI. The results of SmlI digestion did not show any restriction site whereas the digestion with AluI endonuclease revealed the presence of two restriction sites AG^CT at positions 68^69 and 631^632 yielding the presence of three digested fragments with sizes 68-, 563- and 293-bp.The nucleotide sequences of this fragment from camel αS1-Casein gene were submitted to GenBank with the accession number KU145820. In conclusion, the genetic characterization of quantitative traits genes which are associated with the production traits like milk yield and composition is considered an important step towards the genetic improvement of livestock species through the selection of superior animals depending on the favorable alleles and genotypes; marker assisted selection (MAS).Keywords: genetic polymorphism, SNP polymorphism, Maghrabi camels, κ-Casein gene, αS1-Casein gene
Procedia PDF Downloads 614471 The Effect of Metal-Organic Framework Pore Size to Hydrogen Generation of Ammonia Borane via Nanoconfinement
Authors: Jing-Yang Chung, Chi-Wei Liao, Jing Li, Bor Kae Chang, Cheng-Yu Wang
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Chemical hydride ammonia borane (AB, NH3BH3) draws attentions to hydrogen energy researches for its high theoretical gravimetrical capacity (19.6 wt%). Nevertheless, the elevated AB decomposition temperatures (Td) and unwanted byproducts are main hurdles in practical application. It was reported that the byproducts and Td can be reduced with nanoconfinement technique, in which AB molecules are confined in porous materials, such as porous carbon, zeolite, metal-organic frameworks (MOFs), etc. Although nanoconfinement empirically shows effectiveness on hydrogen generation temperature reduction in AB, the theoretical mechanism is debatable. Low Td was reported in AB@IRMOF-1 (Zn4O(BDC)3, BDC = benzenedicarboxylate), where Zn atoms form closed metal clusters secondary building unit (SBU) with no exposed active sites. Other than nanosized hydride, it was also observed that catalyst addition facilitates AB decomposition in the composite of Li-catalyzed carbon CMK-3, MOF JUC-32-Y with exposed Y3+, etc. It is believed that nanosized AB is critical for lowering Td, while active sites eliminate byproducts. Nonetheless, some researchers claimed that it is the catalytic sites that are the critical factor to reduce Td, instead of the hydride size. The group physically ground AB with ZIF-8 (zeolitic imidazolate frameworks, (Zn(2-methylimidazolate)2)), and found similar reduced Td phenomenon, even though AB molecules were not ‘confined’ or forming nanoparticles by physical hand grinding. It shows the catalytic reaction, not nanoconfinement, leads to AB dehydrogenation promotion. In this research, we explored the possible criteria of hydrogen production temperature from nanoconfined AB in MOFs with different pore sizes and active sites. MOFs with metal SBU such as Zn (IRMOF), Zr (UiO), and Al (MIL-53), accompanying with various organic ligands (BDC and BPDC; BPDC = biphenyldicarboxylate) were modified with AB. Excess MOFs were used for AB size constrained in micropores estimated by revisiting Horvath-Kawazoe model. AB dissolved in methanol was added to MOFs crystalline with MOF pore volume to AB ratio 4:1, and the slurry was dried under vacuum to collect AB@MOF powders. With TPD-MS (temperature programmed desorption with mass spectroscopy), we observed Td was reduced with smaller MOF pores. For example, it was reduced from 100°C to 64°C when MOF micropore ~1 nm, while ~90°C with pore size up to 5 nm. The behavior of Td as a function of AB crystalline radius obeys thermodynamics when the Gibbs free energy of AB decomposition is zero, and no obvious correlation with metal type was observed. In conclusion, we discovered Td of AB is proportional to the reciprocal of MOF pore size, possibly stronger than the effect of active sites.Keywords: ammonia borane, chemical hydride, metal-organic framework, nanoconfinement
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