Search results for: circular economy business model (CEBM)
1966 Understanding Student Engagement through Sentiment Analytics of Response Times to Electronically Shared Feedback
Authors: Yaxin Bi, Peter Nicholl
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The rapid advancement of Information and communication technologies (ICT) is extremely influencing every aspect of Higher Education. It has transformed traditional teaching, learning, assessment and feedback into a new era of Digital Education. This also introduces many challenges in capturing and understanding student engagement with their studies in Higher Education. The School of Computing at Ulster University has developed a Feedback And Notification (FAN) Online tool that has been used to send students links to personalized feedback on their submitted assessments and record students’ frequency of review of the shared feedback as well as the speed of collection. The feedback that the students initially receive is via a personal email directing them through to the feedback via a URL link that maps to the feedback created by the academic marker. This feedback is typically a Word or PDF report including comments and the final mark for the work submitted approximately three weeks before. When the student clicks on the link, the student’s personal feedback is viewable in the browser and they can view the contents. The FAN tool provides the academic marker with a report that includes when and how often a student viewed the feedback via the link. This paper presents an investigation into student engagement through analyzing the interaction timestamps and frequency of review by the student. We have proposed an approach to modeling interaction timestamps and use sentiment classification techniques to analyze the data collected over the last five years for a set of modules. The data studied is across a number of final years and second-year modules in the School of Computing. The paper presents the details of quantitative analysis methods and describes further their interactions with the feedback overtime on each module studied. We have projected the students into different groups of engagement based on sentiment analysis results and then provide a suggestion of early targeted intervention for the set of students seen to be under-performing via our proposed model.Keywords: feedback, engagement, interaction modelling, sentiment analysis
Procedia PDF Downloads 1021965 A Rule Adumbrated: Bailment on Terms
Authors: David Gibbs-Kneller
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Only parties to a contract can enforce it. This is the privity of the contract. Carriage contracts frequently involve intermediated relationships. While the carrier and cargo-owner will agree on a contract for carriage, there is no privity or consideration between the cargo-owner and third parties. To overcome this, the contract utilizes ‘bailment on terms’ or the rule in Morris. Morris v C W Martin & Sons Ltd is authority for the following: A sub-bailee and bailor may rely on terms of a bailment where the bailor has consented to sub-bailment “on terms”. Bailment on terms can play a significant part in making litigation decisions and determining liability. It is used in standard form contracts and courts have also strived to find consent to bailment on terms in agreements so as to avoid the consequences of privity of contract. However, what this paper exposes is the false legal basis for this model. Lord Denning gave an account adumbrated of the law of bailments to justify the rule in Morris. What Lord Denning was really doing was objecting to the doctrine of privity. To do so, he wrongly asserted there was a lacuna in law that meant third parties could not avail themselves upon terms of a contract. Next, he provided a false analogy between purely contractual rights and possessory liens. Finally, he gave accounts of authorities to say they supported the rule in Morris when they did not. Surprisingly, subsequent case law on the point has not properly engaged with this reasoning. The Pioneer Container held that since the rule in Morris lay in bailments, the decision is not dependent on the doctrine of privity. Yet the basis for this statement was Morris. Once these reasons have been discounted, all bailment on terms rests on is the claim that the law of bailments is an independent source of law. Bailment on terms should not be retained, for it is contrary to established principles in the law of property, tort, and contract. That undermines the certainty of those principles by risking their collapse because there is nothing that keeps bailment on terms within the confines of bailments only. As such, bailment on terms is not good law and should not be used in standard form contracts or by the courts as a means of determining liability. If bailment on terms is a pragmatic rule to retain, it is recommended that rules governing carriage contracts should be amended.Keywords: bailment, carriage of goods, contract law, privity
Procedia PDF Downloads 2021964 RNA-seq Analysis of Liver from NASH-HCC Model Mouse Treated with Streptozotocin-High Fat Diet
Authors: Bui Phuong Linh, Yuki Sakakibara, Ryuto Tanaka, Elizabeth H. Pigney, Taishi Hashiguchi
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Non-alcoholic steatohepatitis (NASH) is a chronic liver disease, often associated with type II diabetes, which sometimes progresses to more serious conditions such as liver fibrosis and hepatocellular carcinoma (HCC). NASH has become an important health problem worldwide, buttherapeutic agents for NASH have not yet been approved, and animal models with high clinical correlation are required. TheSTAM™ mouse shows the same pathological progression as human NASH patients and has been widely used for both drug efficacy and basic research, such as lipid profiling and gut microbiota research. In this study, we analyzed the RNA-seq data of STAM™mice at each pathological stage (steatosis, steatohepatitis, liver fibrosis, and HCC) and examined the clinical correlation at the genetic level. NASH was induced in male mice by a single subcutaneous injection of 200 µg streptozotocin solution 2 days after birth and feeding with high fat dietafter 4 weeks of age. The mice were sacrificed and livers collected at 6, 8, 10, 12, 16, and 20 weeks of age. For liver samples, the left lateral lobe was snap frozen in liquid nitrogen and stored at -80˚C for RNA-seq analysis. Total RNA of the cells was isolated using RNeasy mini kit. The gene expression of the canonical pathways in NASH progression from steatosis to hepatocellular carcinoma were analyzed, such as immune system process, oxidation-reduction process, lipid metabolic process. Moreover, since it has been reported that genetic traits are involved in the development of NASH-HCC, we next analyzed the genetic mutations in the STAM™mice. The number of individuals showing mutations in Mtorinvolved in Insulin signaling increases as the disease progresses, especially in the liver cancer phase. These results indicated a clinical correlation of gene profiles in the STAM™mouse.Keywords: steatosis, non-alcoholic steatohepatitis, fibrosis, hepatocellular carcinoma, RNA-seq
Procedia PDF Downloads 1491963 3D Numerical Simulation of Undoweled and Uncracked Joints in Short Paneled Concrete Pavements
Authors: K. Sridhar Reddy, M. Amaranatha Reddy, Nilanjan Mitra
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Short paneled concrete pavement (SPCP) with shorter panel size can be an alternative to the conventional jointed plain concrete pavements (JPCP) at the same cost as the asphalt pavements with all the advantages of concrete pavement with reduced thickness, less chance of mid-slab cracking and or dowel bar locking so common in JPCP. Cast-in-situ short concrete panels (short slabs) laid on a strong foundation consisting of a dry lean concrete base (DLC), and cement treated subbase (CTSB) will reduce the thickness of the concrete slab to the order of 180 mm to 220 mm, whereas JPCP was with 280 mm for the same traffic. During the construction of SPCP test sections on two Indian National Highways (NH), it was observed that the joints remain uncracked after a year of traffic. The undoweled and uncracked joints load transfer variability and joint behavior are of interest with anticipation on its long-term performance of the SPCP. To investigate the effects of undoweled and uncracked joints on short slabs, the present study was conducted. A multilayer linear elastic analysis using 3D finite element package for different panel sizes with different thicknesses resting on different types of solid elastic foundation with and without temperature gradient was developed. Surface deflections were obtained from 3D FE model and validated with measured field deflections from falling weight deflectometer (FWD) test. Stress analysis indicates that flexural stresses in short slabs are decreased with a decrease in panel size and increase in thickness. Detailed evaluation of stress analysis with the effects of curling behavior, the stiffness of the base layer and a variable degree of load transfer, is underway.Keywords: joint behavior, short slabs, uncracked joints, undoweled joints, 3D numerical simulation
Procedia PDF Downloads 1791962 The Antioxidant and Antinociceptive Effects of Curcumin in Experimentally Induced Pain in Rats
Authors: Valeriu Mihai But, Sorana Daniela Bolboacă, Adriana Elena Bulboacă
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The nutraceutical compound Curcumin (Curcuma longa L.) is known for its anti-inflammatory, anti-cancer, and antioxidant effects. This study aimed to evaluate the antioxidative and analgesic effects of Curcumin (CC) compared to Tramadol (T) in chemical-induced nociceptive pain in rats. Thirty-five rats were randomly divided into five groups of seven rats each and were treated as follows: C group (control group): treated with saline solution 0.9%, (1 ml, i.p. administration), ethanoic acid (EA) group: pretreated with saline solution 0.9% - 30 min before EA nociceptive pain induction, (1 ml, i.p. administration), T group: pretreated with Tramadol, 10 mg/kg body weight (bw), i.p. administration - 30 min before EA nociceptive pain induction, CC1-group: pretreated with 1 mg/100g bw Curcumin i.p. administration - 2 days before EA pain induction and CC2-group: pretreated with Curcumin 2 mg/100g bw i.p. administration - 2 days before EA nociceptive pain induction. The following oxidative stress parameters were assessed: malondialdehyde (MDA), nitric oxide (NOx), total oxidative status (TOS), total antioxidative capacity (TAC), and thiol (Th). The antalgic activity was measured by the ethanoic acid writhing test. Treatment with Curcumin, both 1 mg/100g bw, and 2 mg/100g bw, showed significant differences as compared with the control group (p<0.001) regarding malondialdehyde (MDA), nitric oxide (NOx), and total oxidative status (TOS) oxidative biomarkers. Pretreatment with 2 mg/100g bw of Curcumin presented a significant decrease in MDA values compared with Tramadol (p<0.001). The TAC significantly increased in pretreatment with Curcumin compared with group control. (p<0.001) The nociceptive response to EA was significantly reduced in Curcumin and Tramadol groups. Treatment with Curcumin at a higher concentration was more effective. In an experimental pain model, this study demonstrates an important antioxidant and antinociceptive activity of Curcumin comparable with Tramadol treatment.Keywords: curcumin, nociception, oxidative stress, pain
Procedia PDF Downloads 1071961 The Relationships between Carbon Dioxide (CO2) Emissions, Energy Consumption and GDP for Israel: Time Series Analysis, 1980-2010
Authors: Jinhoa Lee
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The relationships between environmental quality, energy use and economic output have created growing attention over the past decades among researchers and policy makers. Focusing on the empirical aspects of the role of CO2 emissions and energy use in affecting the economic output, this paper is an effort to fulfill the gap in a comprehensive case study at a country level using modern econometric techniques. To achieve the goal, this country-specific study examines the short-run and long-run relationships among energy consumption (using disaggregated energy sources: crude oil, coal, natural gas, electricity), carbon dioxide (CO2) emissions and gross domestic product (GDP) for Israel using time series analysis from the year 1980-2010. To investigate the relationships between the variables, this paper employs the Phillips–Perron (PP) test for stationarity, Johansen maximum likelihood method for cointegration and a Vector Error Correction Model (VECM) for both short- and long-run causality among the research variables for the sample. The long-run equilibrium in the VECM suggests significant positive impacts of coal and natural gas consumptions on GDP in Israel. In the short run, GDP positively affects coal consumption. While there exists a positive unidirectional causality running from coal consumption to consumption of petroleum products and the direct combustion of crude oil, there exists a negative unidirectional causality running from natural gas consumption to consumption of petroleum products and the direct combustion of crude oil in the short run. Overall, the results support arguments that there are relationships among environmental quality, energy use and economic output but the associations can to be differed by the sources of energy in the case of Israel over of period 1980-2010.Keywords: CO2 emissions, energy consumption, GDP, Israel, time series analysis
Procedia PDF Downloads 6471960 Various Body Measurements of Hair, Boer x Hair F1 Crossbred Kids and Effects of Some Environmental Factors on These Traits
Authors: M. Bolacalı, Y. Öztürk, O. Yılmaz, M. Küçük, M. A. Karslı
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The aim of the study was to determine various body measurements from the birth to the 30-day age of Boer x Hair goats F1 crossbred kids and pure Hair goat kids raised in Van in Eastern Anatolia region, and reveal factors such as the effects of year, dame body weight, genotype, dame age, birth type and sex on this parameter. 49 kids born in 2012 and 76 kids born in 2014 were utilized in the study. In the statistical analysis of various body measurements data was performed using the General Lineer Model procedure in SPSS software. Duncan's multiple range test was used for multiple comparisons. Boer x Hair goats F1 crossbred kids and pure Hair goat kids from various body measurements cidago height, body length, chest length, chest depth, chest circumference, circumference of leg, cannon bone circumference, chest width were determinated in general respectively 29.90 and 27.88 cm; 29.49 and 27.93 cm; 17.28 and 16.68 cm; 13.34 and 12.82 cm; 31.74 and 29.85 cm; 28.43 and 23.95 cm; 5.41 and 5.15 cm; 8.71 and 7.63 cm at birth, respectively; 35.01 and 32.98 cm; 35.20 and 33.30 cm; 18.82 and 18.17 cm; 15.64 and 14.83 cm; 39.08 and 37.30 cm; 34.29 and 29.25 cm; 5.80 and 5.42 cm; 9.87 and 8.85 cm at 30 days age, respectively. Among factors affecting cidago height in this study, the effect of dame body weight and sex were not significant, but genotype, dame age and birth type were significant (P < 0,05 and P < 0,01) at birth; dame body weight effect of the cidago height was not significant, but the effect of genotype, birth type, of dame age and sex were significant (P < 0.05, P < 0.05 and P<0.001) at 30-day age. The effect of genotype and sex of body length were not significant, but dam age, dame body weight and birth type were significant (P < 0.05, P < 0.05 and P<0.001, respectively) at birth; the effect of sex to body length was not significant, but genotype, dame age, dame body weight and birth type were significant (P < 0.01, P < 0.05, P < 0.05 and P < 0.001, respectively) at 30-day age. While circumference of leg was insignificant the effect of dame age and sex, genotype, dame body weight and type of the birth were significant (P < 0.001, P < 0.05 and P < 0.001) at birth; the circumstance of leg at 30-day age was found to be important the effect of examined other factors except for sex (P < 0.05 and P < 0.001). The obtained results, when considered in terms of a variety of body sizes, from birth to 30-day age growth period, showed that the kids of Boer x Hair Goat F1 hybrids have higher values than the kids of Hair Goats.Keywords: Boer x hair goat F1 crossbred, hair goat, body measurements, cidago height
Procedia PDF Downloads 3461959 The Emancipatory Methodological Approach to the Organizational Problems Management
Authors: Slavica P. Petrovic
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One of the key dimensions of management problems in organizations refers to the relations between stakeholders. The management problems that are characterized by conflict and coercion, in which participants do not agree on the ends and means, in which different groups, i.e., individuals, strive to – using the power they have – impose on others their favoured strategy and decisions represent the relevant research subject. Creatively managing the coercive problems in organizations, in which the sources of power can be identified, implies the emancipatory paradigm and the use of corresponding systems methodology. The main research aim is to critically reassess the theoretical foundations and methodological and methodical development of Critical Systems Heuristics (CSH) – as a valid representative of the emancipatory paradigm – in order to determine the conditions, ways, and achievements of its application in managing the coercive problems in organizations. The basic hypothesis is that CSH, as the emancipatory methodology, given its own theoretical foundations and methodological-methodical development, can be employed in a scientifically based and practically useful manner in creative addressing the coercive problems. The scientific instrumentarium corresponding to this research aim is critical systems thinking with its three key commitments to: a) Critical awareness of the strengths and weaknesses of each research instrument (theory, methodology, method, technique, model) for structuring the problem situations in organizations, b) Improvement of managing the coercive problems in organizations, and c) Pluralism – respect the different perceptions and interpretations of problem situations, and enable the combined use of research instruments. The relevant research result is that CSH – considering its theoretical foundations, methodological and methodical development – enables to reveal the normative content of the proposed or existing designs of organizational systems. Accordingly, it can be concluded that through the use of critically heuristic categories and dialectical debate between those involved and those affected by the designs, but who are not included in designing organizational systems, CSH endeavours to – in the application – support the process of improving position of all stakeholders.Keywords: coercion and conflict in organizations, creative management, critical systems heuristics, the emancipatory systems methodology
Procedia PDF Downloads 4411958 Calculation of Fractal Dimension and Its Relation to Some Morphometric Characteristics of Iranian Landforms
Authors: Mitra Saberi, Saeideh Fakhari, Amir Karam, Ali Ahmadabadi
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Geomorphology is the scientific study of the characteristics of form and shape of the Earth's surface. The existence of types of landforms and their variation is mainly controlled by changes in the shape and position of land and topography. In fact, the interest and application of fractal issues in geomorphology is due to the fact that many geomorphic landforms have fractal structures and their formation and transformation can be explained by mathematical relations. The purpose of this study is to identify and analyze the fractal behavior of landforms of macro geomorphologic regions of Iran, as well as studying and analyzing topographic and landform characteristics based on fractal relationships. In this study, using the Iranian digital elevation model in the form of slopes, coefficients of deposition and alluvial fan, the fractal dimensions of the curves were calculated through the box counting method. The morphometric characteristics of the landforms and their fractal dimension were then calculated for 4criteria (height, slope, profile curvature and planimetric curvature) and indices (maximum, Average, standard deviation) using ArcMap software separately. After investigating their correlation with fractal dimension, two-way regression analysis was performed and the relationship between fractal dimension and morphometric characteristics of landforms was investigated. The results show that the fractal dimension in different pixels size of 30, 90 and 200m, topographic curves of different landform units of Iran including mountain, hill, plateau, plain of Iran, from1.06in alluvial fans to1.17in The mountains are different. Generally, for all pixels of different sizes, the fractal dimension is reduced from mountain to plain. The fractal dimension with the slope criterion and the standard deviation index has the highest correlation coefficient, with the curvature of the profile and the mean index has the lowest correlation coefficient, and as the pixels become larger, the correlation coefficient between the indices and the fractal dimension decreases.Keywords: box counting method, fractal dimension, geomorphology, Iran, landform
Procedia PDF Downloads 811957 Nursing Experience for a Lung Cancer Patient Undergoing First Time Concurrent Chemotherapy and Radiation Therapy
Authors: Hui Ling Chen
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This article describes the experience of caring for a 68-year-old lung cancer patient undergoing the initial stage of concurrent chemotherapy and radiation therapy during the period of October 21 to November 16. In this study, the author collected data through observation, interviews, medical examination, and the use of Roy’s adaptation model as a guide for data collection and assessment. This study confirmed that chemotherapy induced nausea and vomiting, and radiation therapy impaired skin integrity. At the same time, the patient experienced an anxious reaction to the initial cancer diagnosis and the insertion of subcutaneous infusion ports at the start of medical treatment. Similarly, the patient’s wife shares his anxiety, not to mention the feeling of inadequacy from the lack of training in cancer care. In response, the nursing intervention strategy has included keeping the patient and his family informed of his treatment progress, transfer of cancer care knowledge, and providing them with spiritual support. For example, the nursing staff has helped them draw up a mutually agreeable dietary plan that best suits the wife’s cooking skills, provided them with knowledge in pre- and post-radiation skin care, as well as means to cope with nausea and vomiting reactions. The nursing staff has also worked on building rapport with the patient and his spouse, providing them with encouragement, caring attention and companionship. After the patient was discharged from the hospital, the nursing staff followed up with caring phone calls to help the patient and his family make life-style adjustments to normalcy. The author hopes that his distinctive nursing experience can be useful as a reference for the clinical care of lung cancer patients undergoing the initial stage of concurrent chemotherapy and radiation therapy treatment.Keywords: lung cancer, initiate diagnosis, concurrent chemotherapy and radiation therapy, nursing care
Procedia PDF Downloads 1401956 Comparative Analysis of Short and Long Term Salt Stress on the Photosynthetic Apparatus and Chloroplast Ultrastructure of Thellungiella salsuginea
Authors: Rahma Goussi, Walid Derbali, Arafet Manaa, Simone Cantamessa, Graziella Berta, Chedly Abdelly, Roberto Barbato
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Salinity is one of the most important abiotic affecting plant growth and productivity worldwide. Photosynthesis, together with cell growth, is among the primary processes to be affected by salinity. Here, we report the effects of salinity stress on the primary processes of photosynthesis in a model halophyte Thellungiella Salsuginea. Plants were cultivated in hydroponic system with different NaCl concentrations (0, 100, 200 and 400 mM) during 2 weeks. The obtained results showed an obvious change in the photosynthetic efficiency of photosystem I (PSI) and phostosytem II (PSII), related to NaCl concentration supplemented to the medium and the stress duration considered. With moderate salinity (100 and 200 mM NaCl), no significant variation was observed in photosynthetic parameters of PSI and PSII and Chl fluorescence whatever the time of stress application. Also, the photosynthesis apparatus Fo, Fm and Fv fluorescence, as well as Fv/Fm were not affected by salt stress. While a significant decrease was observed on quantum yields Y(I), Y(II) and electron transport rate ETR(I), ETR(II) under high salt treatment (400 mM NaCl) with prolonged period (15 days). This reduction is quantitatively compensated by a corresponding increase of energy dissipation Y(NPQ) and a progressive decrease in Fv/Fm under salt treatment. The intensity of the OJIP fluorescence transient decreased with increase in NaCl concentration, with a major effect observed during prolonged period of salt stress. Ultrastructural analysis with Light Microscopy and Transmission Electron Microscopy of T. salsuginea chloroplasts showed some cellular changes, such as the shape of the mesophyll cells and number of chloroplast/cell only under higher NaCl concentration. Salt-stress caused the swelling of thylakoids in T. Salsuginea mesophyll with more accumulation of starch as compared to control plant.Keywords: fluorescence, halophyte, photosynthesis, salt stress
Procedia PDF Downloads 3741955 Cooperative Robot Application in a Never Explored or an Abandoned Sub-Surface Mine
Authors: Michael K. O. Ayomoh, Oyindamola A. Omotuyi
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Autonomous mobile robots deployed to explore or operate in a never explored or an abandoned sub-surface mine requires extreme effectiveness in coordination and communication. In a bid to transmit information from the depth of the mine to the external surface in real-time and amidst diverse physical, chemical and virtual impediments, the concept of unified cooperative robots is seen to be a proficient approach. This paper presents an effective [human → robot → task] coordination framework for effective exploration of an abandoned underground mine. The problem addressed in this research is basically the development of a globalized optimization model premised on time series differentiation and geometrical configurations for effective positioning of the two classes of robots in the cooperation namely the outermost stationary master (OSM) robots and the innermost dynamic task (IDT) robots for effective bi-directional signal transmission. In addition, the synchronization of a vision system and wireless communication system for both categories of robots, fiber optics system for the OSM robots in cases of highly sloppy or vertical mine channels and an autonomous battery recharging capability for the IDT robots further enhanced the proposed concept. The OSM robots are the master robots which are positioned at strategic locations starting from the mine open surface down to its base using a fiber-optic cable or a wireless communication medium all subject to the identified mine geometrical configuration. The OSM robots are usually stationary and function by coordinating the transmission of signals from the IDT robots at the base of the mine to the surface and in a reverse order based on human decisions at the surface control station. The proposed scheme also presents an optimized number of robots required to form the cooperation in a bid to reduce overall operational cost and system complexity.Keywords: sub-surface mine, wireless communication, outermost stationary master robots, inner-most dynamic robots, fiber optic
Procedia PDF Downloads 2111954 Designing Energy Efficient Buildings for Seasonal Climates Using Machine Learning Techniques
Authors: Kishor T. Zingre, Seshadhri Srinivasan
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Energy consumption by the building sector is increasing at an alarming rate throughout the world and leading to more building-related CO₂ emissions into the environment. In buildings, the main contributors to energy consumption are heating, ventilation, and air-conditioning (HVAC) systems, lighting, and electrical appliances. It is hypothesised that the energy efficiency in buildings can be achieved by implementing sustainable technologies such as i) enhancing the thermal resistance of fabric materials for reducing heat gain (in hotter climates) and heat loss (in colder climates), ii) enhancing daylight and lighting system, iii) HVAC system and iv) occupant localization. Energy performance of various sustainable technologies is highly dependent on climatic conditions. This paper investigated the use of machine learning techniques for accurate prediction of air-conditioning energy in seasonal climates. The data required to train the machine learning techniques is obtained using the computational simulations performed on a 3-story commercial building using EnergyPlus program plugged-in with OpenStudio and Google SketchUp. The EnergyPlus model was calibrated against experimental measurements of surface temperatures and heat flux prior to employing for the simulations. It has been observed from the simulations that the performance of sustainable fabric materials (for walls, roof, and windows) such as phase change materials, insulation, cool roof, etc. vary with the climate conditions. Various renewable technologies were also used for the building flat roofs in various climates to investigate the potential for electricity generation. It has been observed that the proposed technique overcomes the shortcomings of existing approaches, such as local linearization or over-simplifying assumptions. In addition, the proposed method can be used for real-time estimation of building air-conditioning energy.Keywords: building energy efficiency, energyplus, machine learning techniques, seasonal climates
Procedia PDF Downloads 1131953 Effect of Different Thermomechanical Cycles on Microstructure of AISI 4140 Steel
Authors: L.L. Costa, A. M. G. Brito, S. Khan, L. Schaeffer
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Microstructure resulting from the forging process is studied as a function of variables such as temperature, deformation, austenite grain size and cooling rate. The purpose of this work is to study the thermomechanical behavior of DIN 42CrMo4 (AISI 4140) steel maintained at the temperatures of 900°, 1000°, 1100° and 1200°C for the austenization times of 22, 66 and 200 minutes each and subsequently forged. These samples were quenched in water in order to study the austenite grain and to investigate the microstructure instead of quenching the annealed samples after forging they were cooled down naturally in the air. The morphologies and properties of the materials such as hardness; prepared by these two different routes have been compared. In addition to the forging experiments, the numerical simulation using the finite element model (FEM), microhardness profiles and metallography images have been presented. Forging force vs position curves has been compared with metallographic results for each annealing condition. The microstructural phenomena resulting from the hot conformation proved that longer austenization time and higher temperature decrease the forging force in the curves. The complete recrystallization phenomenon (static, dynamic and meta dynamic) was observed at the highest temperature and longest time i.e., the samples austenized for 200 minutes at 1200ºC. However, higher hardness of the quenched samples was obtained when the temperature was 900ºC for 66 minutes. The phases observed in naturally cooled samples were exclusively ferrite and perlite, but the continuous cooling diagram indicates the presence of austenite and bainite. The morphology of the phases of naturally cooled samples has shown that the phase arrangement and the previous austenitic grain size are the reasons to high hardness in obtained samples when temperature were 900ºC and 1100ºC austenization times of 22 and 66 minutes, respectively.Keywords: austenization time, thermomechanical effects, forging process, steel AISI 4140
Procedia PDF Downloads 1421952 Investigating the Relationship Between Alexithymia and Mobile Phone Addiction Along with the Mediating Role of Anxiety, Stress and Depression: A Path Analysis Study and Structural Model Testing
Authors: Pouriya Darabiyan, Hadis Nazari, Kourosh Zarea, Saeed Ghanbari, Zeinab Raiesifar, Morteza Khafaie, Hanna Tuvesson
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Introduction Since the beginning of mobile phone addiction, alexithymia, depression, anxiety and stress have been stated as risk factors for Internet addiction, so this study was conducted with the aim of investigating the relationship between Alexithymia and Mobile phone addiction along with the mediating role of anxiety, stress and depression. Materials and methods In this descriptive-analytical and cross-sectional study in 2022, 412 students School of Nursing & Midwifery of Ahvaz Jundishapur University of Medical Sciences were included in the study using available sampling method. Data collection tools were: Demographic Information Questionnaire, Toronto Alexithymia Scale (TAS-20), Depression, Anxiety, Stress Scale (DASS-21) and Mobile Phone Addiction Index (MPAI). Frequency, Pearson correlation coefficient test and linear regression were used to describe and analyze the data. Also, structural equation models and path analysis method were used to investigate the direct and indirect effects as well as the total effect of each dimension of Alexithymia on Mobile phone addiction with the mediating role of stress, depression and anxiety. Statistical analysis was done by SPSS version 22 and Amos version 16 software. Results Alexithymia was a predictive factor for mobile phone addiction. Also, Alexithymia had a positive and significant effect on depression, anxiety and stress. Depression, anxiety and stress had a positive and significant effect on mobile phone addiction. Depression, anxiety and stress variables played the role of a relative mediating variable between Alexithymia and mobile phone addiction. Alexithymia through depression, anxiety and stress also has an indirect effect on Internet addiction. Conclusion Alexithymia is a predictive factor for mobile phone addiction; And the variables of depression, anxiety and stress play the role of a relative mediating variable between Alexithymia and mobile phone addiction.Keywords: alexithymia, mobile phone, depression, anxiety, stress
Procedia PDF Downloads 961951 Regression of Fibrosis by Apigenin in Thioacetamide-Induced Liver Fibrosis Rat Model through Suppression of HIF-1/FAK Pathway
Authors: Hany M. Fayed, Rehab F. Abdel-Rahman, Alyaa F. Hessin, Hanan A. Ogaly, Gihan F. Asaad, Abeer A. A. Salama, Sahar Abdelrahman, Mahmoud S. Arbid, Marwan Abd Elbaset Mohamed
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Liver fibrosis is a serious global health problem that occurs as a result of a variety of chronic liver disorders. Apigenin, a flavonoid found in many plants, has several pharmacological properties. The aim of this study was to evaluate the antifibrotic efficacy of apigenin (APG) against experimentally induced hepatic fibrosis in rats via using thioacetamide (TAA) and to explore the possible underlying mechanisms. TAA (100 mg/kg, i.p.) was given three times each week for two weeks to induce liver fibrosis. After TAA injections, APG was given orally (5 and 10 mg/kg) daily for two weeks. Biochemical, molecular, histological and immunohistochemical analyses were performed on blood and liver tissue samples. The functioning of the liver, oxidative stress, inflammation, and liver fibrosis indicators were all evaluated. The findings showed that TAA markedly increased the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), as well as the levels of malondialdehyde (MDA), focal adhesion kinase (FAK), hypoxia-inducible factor-1 (HIF-1), nuclear factor-κB (NF-κB), transforming growth factor-beta (TGF-β), tumor necrosis factor-alpha (TNF-α) and interleukin-1β (IL-1β) with a reduction in albumin, total protein, A/G ratio, GSH content and interleukin-10 (IL-10). Moreover, TAA elevated the content of collagen I, α -smooth muscle actin (α-SMA), and hydroxyproline in the liver. The treatment with APG in a dose-dependent manner has obviously prevented these alterations and amended the harmful effects induced by TAA. The histopathological and immunohistochemical observations supported this biochemical evidence. The higher dose of APG produced the most significant antifibrotic effect. As a result of these data, APG appears to be a promising antifibrotic drug and could be used as a new herbal medication or dietary supplement in the future for the treatment of liver fibrosis. This effect might be related to the inhibition of the HIF-1/FAK signaling pathway.Keywords: apigenin, FAK, HIF-1, liver fibrosis, rat, thioacetamide
Procedia PDF Downloads 1331950 The Triad Experience: Benefits and Drawbacks of the Paired Placement of Student Teachers in Physical Education
Authors: Todd Pennington, Carol Wilkinson, Keven Prusak
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Traditional models of student teaching practices typically involve the placement of a student teacher with an experienced mentor teacher. However, due to the ever-decreasing number of quality placements, an alternative triad approach is the paired placement of student teachers with one mentor teacher in a community of practice. This study examined the paired-placement of student teachers in physical education to determine the benefits and drawbacks after a 14-week student teaching experience. PETE students (N = 22) at a university in the United States were assigned to work in a triad with a student teaching partner and a mentor teacher, making up eleven triads for the semester. The one exception was a pair that worked for seven weeks at an elementary school and then for seven weeks at a junior high school, thus having two mentor teachers and participating in two triads. A total of 12 mentor teachers participated in the study. All student teachers and mentor teachers volunteered and agreed to participate. The student teaching experience was structured so that students engaged in: (a) individual teaching (one teaching the lesson with the other observing), (b) co-planning, and (c) peer coaching. All students and mentor teachers were interviewed at the conclusion of the experience. Using interview data, field notes, and email response data, the qualitative data was analyzed using the constant comparative method. The benefits of the paired placement experience emerged into three categories (a) quality feedback, (b) support, and (c) collaboration. The drawbacks emerged into four categories (a) unrealistic experience, (b) laziness in preparation, (c) lack of quality feedback, and (d) personality mismatch. Recommendations include: providing in-service training prior to student teaching to optimize the triad experience, ongoing seminars throughout the experience specifically designed for triads, and a hybrid model of paired placement for the first half of student teaching followed by solo student teaching for the second half of the experience.Keywords: community of practice, paired placement, physical education, student teaching
Procedia PDF Downloads 4001949 Effects of Earthquake Induced Debris to Pedestrian and Community Street Network Resilience
Authors: Al-Amin, Huanjun Jiang, Anayat Ali
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Reinforced concrete frames (RC), especially Ordinary RC frames, are prone to structural failures/collapse during seismic events, leading to a large proportion of debris from the structures, which obstructs adjacent areas, including streets. These blocked areas severely impede post-earthquake resilience. This study uses computational simulation (FEM) to investigate the amount of debris generated by the seismic collapse of an ordinary reinforced concrete moment frame building and its effects on the adjacent pedestrian and road network. A three-story ordinary reinforced concrete frame building, primarily designed for gravity load and earthquake resistance, was selected for analysis. Sixteen different ground motions were applied and scaled up until the total collapse of the tested building to evaluate the failure mode under various seismic events. Four types of collapse direction were identified through the analysis, namely aligned (positive and negative) and skewed (positive and negative), with aligned collapse being more predominant than skewed cases. The amount and distribution of debris around the collapsed building were assessed to investigate the interaction between collapsed buildings and adjacent street networks. An interaction was established between a building that collapsed in an aligned direction and the adjacent pedestrian walkway and narrow street located in an unplanned old city. The FEM model was validated against an existing shaking table test. The presented results can be utilized to simulate the interdependency between the debris generated from the collapse of seismic-prone buildings and the resilience of street networks. These findings provide insights for better disaster planning and resilient infrastructure development in earthquake-prone regions.Keywords: building collapse, earthquake-induced debris, ORC moment resisting frame, street network
Procedia PDF Downloads 841948 Semantic Search Engine Based on Query Expansion with Google Ranking and Similarity Measures
Authors: Ahmad Shahin, Fadi Chakik, Walid Moudani
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Our study is about elaborating a potential solution for a search engine that involves semantic technology to retrieve information and display it significantly. Semantic search engines are not used widely over the web as the majorities are still in Beta stage or under construction. Many problems face the current applications in semantic search, the major problem is to analyze and calculate the meaning of query in order to retrieve relevant information. Another problem is the ontology based index and its updates. Ranking results according to concept meaning and its relation with query is another challenge. In this paper, we are offering a light meta-engine (QESM) which uses Google search, and therefore Google’s index, with some adaptations to its returned results by adding multi-query expansion. The mission was to find a reliable ranking algorithm that involves semantics and uses concepts and meanings to rank results. At the beginning, the engine finds synonyms of each query term entered by the user based on a lexical database. Then, query expansion is applied to generate different semantically analogous sentences. These are generated randomly by combining the found synonyms and the original query terms. Our model suggests the use of semantic similarity measures between two sentences. Practically, we used this method to calculate semantic similarity between each query and the description of each page’s content generated by Google. The generated sentences are sent to Google engine one by one, and ranked again all together with the adapted ranking method (QESM). Finally, our system will place Google pages with higher similarities on the top of the results. We have conducted experimentations with 6 different queries. We have observed that most ranked results with QESM were altered with Google’s original generated pages. With our experimented queries, QESM generates frequently better accuracy than Google. In some worst cases, it behaves like Google.Keywords: semantic search engine, Google indexing, query expansion, similarity measures
Procedia PDF Downloads 4241947 Remote Sensing and Geographic Information Systems for Identifying Water Catchments Areas in the Northwest Coast of Egypt for Sustainable Agricultural Development
Authors: Mohamed Aboelghar, Ayman Abou Hadid, Usama Albehairy, Asmaa Khater
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Sustainable agricultural development of the desert areas of Egypt under the pressure of irrigation water scarcity is a significant national challenge. Existing water harvesting techniques on the northwest coast of Egypt do not ensure the optimal use of rainfall for agricultural purposes. Basin-scale hydrology potentialities were studied to investigate how available annual rainfall could be used to increase agricultural production. All data related to agricultural production included in the form of geospatial layers. Thematic classification of Sentinal-2 imagery was carried out to produce the land cover and crop maps following the (FAO) system of land cover classification. Contour lines and spot height points were used to create a digital elevation model (DEM). Then, DEM was used to delineate basins, sub-basins, and water outlet points using the Soil and Water Assessment Tool (Arc SWAT). Main soil units of the study area identified from Land Master Plan maps. Climatic data collected from existing official sources. The amount of precipitation, surface water runoff, potential, and actual evapotranspiration for the years (2004 to 2017) shown as results of (Arc SWAT). The land cover map showed that the two tree crops (olive and fig) cover 195.8 km2 when herbaceous crops (barley and wheat) cover 154 km2. The maximum elevation was 250 meters above sea level when the lowest one was 3 meters below sea level. The study area receives a massive variable amount of precipitation; however, water harvesting methods are inappropriate to store water for purposes.Keywords: water catchements, remote sensing, GIS, sustainable agricultural development
Procedia PDF Downloads 1121946 Enhancement of Aircraft Longitudinal Stability Using Tubercles
Authors: Muhammad Umer, Aishwariya Giri, Umaiyma Rakha
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Mimicked from the humpback whale flippers, the application of tubercle technology is seen to be particularly advantageous at high angles of attack. This particular advantage is of paramount importance when it comes to structures producing lift at high angles of attack. This characteristic of the technology makes it ideal for horizontal stabilizers and selecting the same as the subject of study to identify and exploit the advantage highlighted by researchers on airfoils, this project aims in establishing a foundation for the application of the bio-mimicked technology on an existing aircraft. Using a baseline and 2 tubercle configuration integrated models, the project targets to achieve the twin aim of highlighting the possibility and merits over the base model and also choosing the right configuration in providing the best characteristic suitable for high angles of attack. To facilitate this study, the required models are generated using Solidworks followed by trials in a virtual aerodynamic environment using Fluent in Ansys for resolving the project objectives. Following a structured plan, the aim is to initially identify the advantages mathematically and then selecting the optimal configuration, simulate the end configuration at angles mimicking the actual operation envelope for the particular structure. Upon simulating the baseline configuration at various angles of attack, the stall angle was determined to be 22 degrees. Thus, the tubercle configurations will be simulated and compared at 4 different angles of attacks: 0, 10, 20, and 24. Further, after providing the optimum configuration of horizontal stabilizers, this study aims at the integration of aircraft structure so that the results better imply the end deliverables of real life application. This draws the project scope closer at this point into longitudinal static stability considerations and improvements in the manoeuvrability characteristics. The objective of the study is to achieve a complete overview ready for real life application with marked benefits obtainable from bio morphing of the tubercle technology.Keywords: flow simulation, horizontal stabilizer, stability enhancement, tubercle
Procedia PDF Downloads 3191945 Characterization of Human Papillomavirus Genotypes and Their Correlates among Women Living with HIV Attending Antiretroviral Therapy Clinic in Mukono, Uganda
Authors: Nantale Prossy Nabatte, Josephat Nyagero, Elizabeth Kemigisha
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Background: Human Papilloma Virus (HPV) is a prevalent sexually transmitted infection (STI) in the world. It is important to screen for HPV so that women found positive receive early treatment to prevent the development of cervical cancer. The broad aim of the research was to explore the types, occurrence, and associated correlates of HPV infection by genotyping Human papillomavirus among a cohort of WLHIV attending an antiretroviral therapy clinic in Mukono, Uganda. Methods: A cross-sectional study was used to collect data for socio-demographic, sexual practices, and medical history factors associated with HPV genotypes using a pretested interview guide subjected to 342 WLHIV. The respondents’ results for HPV genotypes were obtained retrospectively from respective laboratory records. Data was entered in Epidata v4.6 and analysed using STATA V14. The prevalence of hr-HPV was estimated as a proportion of the entire sample size. Analysis for the correlates of hr-HPV infection was done using a modified Poisson regression model. Results: Slightly more than a half of respondents were aged below 35 years (56.7%), married (52.6%), and with a primary level of education (51.2%). The prevalence of hr-HPV was 39.8% at a 95% confidence interval (CI: 34.40- 44.78). The hr-HPV was higher among those between 30-34 years of age (n= 41, 30.2%) than those between the age of 45-49 years (n=16, 11.8%). In terms of associated correlates, age 45-49 years (aPR: 1.95, 95% CI: 1.41- 2.69), being married (aPR: 1.30, 95% CI: 1.00, 1.69), use of condoms (aPR: 1.31, 95% CI: 1.00 -1.71) and age of sexual debut (aPR: 1.42, 95% CI: 1.08-1.87) were significantly associated with Human papillomavirus genotypes. Conclusion and Recommendation: The prevalence of hr-HPV infection was high, indicative of a risk to the health of WLHIV in Mukono, Uganda, and worldwide at large. The correlates are age 45-49 years, being married, use of condoms, and age of sexual debut. Based on the results, it is recommended that the implementing teams in such projects put more emphasis on the diagnosis of hr-HPV infection and monitoring the treatment. More research is required to determine the effect of ART therapy on hr-HPV persistence.Keywords: human papillomavirus genotypes, and their correlates, among women living with HIV, attending antiretroviral clinic
Procedia PDF Downloads 901944 Synergistic Cytotoxicity of Cisplatin and Taxol in Overcoming Taxol Resistance through the Inhibition of LDHA in Oral Squamous Cell Carcinoma
Authors: Lin Feng, Ling-Ling E., Hong-Chen Liu
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The development of chemoresistance in patients represents a major challenge in cancer treatment. Lactate dehydrogenase‑A (LDHA) is one of the principle isoforms of LDH that is expressed in breast tissue, controlling the conversion of pyruvate to lactate and also playing a significant role in the metabolism of glucose. The aim of this study was to identify whether LDHA was involved in oral cancer cell resistance to Taxol and whether the downregulation of LDHA, as a result of cisplatin treatment, may overcome Taxol resistance in human oral squamous cells. The OECM‑1 oral epidermal carcinoma cell line was used, which has been widely used as a model of oral cancer in previous studies. The role of LDHA in Taxol and cisplatin resistance was investigated and the synergistic cytotoxicity of cisplatin and/or Taxol in oral squamous cells was analyzed. Cell viability was analyzed by MTT assay, LDHA expression was analyzed by western blot analysis and siRNA transfection was performed to knock down LDHA expression. The present study results showed that decreased levels of LDHA were responsible for the resistance of oral cancer cells to cisplatin (CDDP). CDDP treatments downregulated LDHA expression and lower levels of LDHA were detected in the CDDP‑resistant oral cancer cells compared with the CDDP‑sensitive cells. By contrast, the Taxol‑resistant cancer cells showed elevated LDHA expression levels. In addition, small interfering RNA‑knockdown of LDHA sensitized the cells to Taxol but desensitized them to CDDP treatment while exogenous expression of LDHA sensitized the cells to CDDP, but desensitized them to Taxol. The present study also revealed the synergistic cytotoxicity of CDDP and Taxol for killing oral cancer cells through the inhibition of LDHA. This study highlights LDHA as a novel therapeutic target for overcoming Taxol resistance in oral cancer patients using the combined treatments of Taxol and CDDP.Keywords: cisplatin, Taxol, carcinoma, oral squamous cells
Procedia PDF Downloads 4151943 The Extent of Proliferation, Apoptosis and Angiogenesis at the Site of Injury Determine the Course of Healing Either as Scar Free or as Scarred One in the Appendages of Lizard
Authors: Isha Ranadive, Sonam Patel, Suresh Balakrishnan
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It has been observed that in lizards wound can be healed by either a scar free mechanism or by scarring. The animal model used to study both these healing processes was Northern House Gecko. In lizard, the tail when amputated heals by scar free mechanism which allows it to regenerate, the same is not seen when the limb is amputated. Proliferation, apoptosis, and angiogenesis are the main events which succeed an injury. We observed that proliferation of the cells beneath the wound epidermis was much higher in case of wound healing in tail. This could be because after the wound gets covered by the epithelium, it enters in to a cross-talk with the underlying mesenchyme to recruit a pool of blastemal cells which proliferate and later differentiate to form the lost part through epimorphic regeneration. This was substantiated by mRNA expression levels of various FGFs which facilitate the cross-talk and also by PCNA which is a marker for proliferation. Western blot result reaffirms the same notion. However, in case of the limb, the rate of apoptosis was more than proliferation as there are a lot of debris that needs to be removed. We came to this conclusion as we observed that p53 the apoptotic gene was highly upregulated in case of the scarred tissue. Further, we confirmed this result by checking the anti-apoptotic gene bcl2 and found it to be significantly down-regulated. As we noticed heightened proliferation in the case of scar-free wound healing in tail, angiogenesis was targeted for the study. This is because, when the cells are proliferating they require constant supply of blood and hence neo-vascularization is inevitable. It was observed that the marker of angiogenesis, VEGF, was expressed more during wound healing as compared to the resting stage of tail. Moreover, a high up-regulation was seen in KDR, a receptor of VEGF. Thus, this study reveals how proliferation, apoptosis, and angiogenesis play a key role in the scar-free as well as scarred wound healing.Keywords: epimorphic regeneration, injury, northern house gecko, wound healing
Procedia PDF Downloads 2441942 Arsenic and Fluoride Contamination in Lahore, Pakistan: Spatial Distribution, Mineralization Control and Sources
Authors: Zainab Abbas Soharwardi, Chunli Su, Harold Wilson Tumwitike Mapoma, Syed Zahid Aziz, Mahmut Ince
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This study investigated the spatial variations of groundwater chemistry used by communities in Lahore city with emphasis on arsenic (As) and fluoride (F) levels. A total of 472 tubewell samples were collected from 7 towns and analyzed for physical and chemical parameters, including pH, turbidity, electrical conductivity (EC), total dissolved solids (TDS), total hardness, HCO3, Ca2+, Mg2+, Na+, K+, SO42-, Cl-, NO3-, NO2-, F- and As. There were significant spatial variations observed for total hardness, TDS, HCO3, NO3 and As. In general, the south-east of the city displayed higher TH and HCO3 while the north-east showed significantly higher As concentrations attributed to the heterogeneity of the aquifer and industrial activities. In most cases, As was higher than WHO limit value. Indiscriminate disposal of domestic and commercial wastewater into River Ravi is the cause of elevated NO3 observed in the north-west compared to other places in the area. Investigation of the groundwater type revealed facies in the order: Ca-Mg-HCO3-SO4 > Mg-Ca-HCO3-SO4 > Ca-Mg-HCO3-SO4-Cl > Mg-Ca-HCO3-SO4 > Ca-HCO3-SO4 > Ca-Mg-SO4-HCO3. The plausible mineralization control mechanism seems to be that of carbonate weathering, although silicate weathering is probable. Moreover, PHREEQC model results showed that the groundwater was under saturated with respect to evaporites (anhydrite, fluorite, gypsum and halite) while generally equilibrium to saturated with respect to aragonite, calcite and dolomite. The Hierarchical Cluster Analysis (HCA) showed that pH significantly affected As, F, NO3 and NO2 while HCO3 contributing most to the observed TDS values in Lahore. It is concluded that inherent mineral dissolution/ precipitation, pH, oxic conditions, anthropogenic activities, atmospheric transport/ wet deposition, microbial activities and surface soil characteristics play their significant roles in elevating both As and F in the city's groundwater.Keywords: Lahore, arsenic, fluoride, groundwater
Procedia PDF Downloads 5481941 Transforming Educational Leadership With Innovative Administrative Strategies
Authors: Kofi Nkonkonya Mpuangnan, Samantha Govender, Hlengiwe Romualda Mhlongo
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Educational leaders are skilled architects crafting a vibrant environment where growth, creativity, and adaptability can flourish within schools. Their journey is one of transformation, urging them to explore administrative strategies that align seamlessly with evolving educational models and cater to the specific needs of students, educators, and stakeholders. Through this committed effort to innovate, they seek to enhance the effectiveness and influence of educational systems, paving the way for a more inclusive and forward-thinking educational environment. In this context, the authors explored the concept of transforming educational leadership with administrative strategies in alignment with the following research objectives. To find the strategies that can be adopted by transformation leaders to promote effective administrative practices in an educational setting and to explore the roles of educational leaders in promoting collaboration in education. To find answers to these questions, a systematic literature review underpinned by the transformational leadership model was adopted. Therefore, concepts integrated from a variety of outlets, including academic journals, conference proceedings, and reports found within SCOPUS, WoS, and IBSS databases. A search was aided using specific themes like innovative administrative practices, the roles of educational leaders, and interdisciplinary approaches to administrative practices. The process of conducting the search adhered to the five-step framework, which was subjected to inclusion and exclusion of studies. It was found that transformational leadership, agile methodologies, employee wellbeing, seminars and workshops could foster a culture of innovation and creativity among teachers and staff to transform administrative practices in education settings. It was recommended that professional development programs be organized periodically for educational leaders in educational institutions to help them revitalize their knowledge and skills in educational administration.Keywords: educational leadership, innovative strategies, administrative practices, professional development, stakeholder engaement, student outcome
Procedia PDF Downloads 921940 Balancing a Rotary Inverted Pendulum System Using Robust Generalized Dynamic Inverse: Design and Experiment
Authors: Ibrahim M. Mehedi, Uzair Ansari, Ubaid M. Al-Saggaf, Abdulrahman H. Bajodah
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This paper presents a methodology for balancing a rotary inverted pendulum system using Robust Generalized Dynamic Inversion (RGDI) under influence of parametric variations and external disturbances. In GDI control, dynamic constraints are formulated in the form of asymptotically stable differential equation which encapsulates the control objectives. The constraint differential equations are based on the deviation function of the angular position and its rates from their reference values. The constraint dynamics are inverted using Moore-Penrose Generalized Inverse (MPGI) to realize the control expression. The GDI singularity problem is addressed by augmenting a dynamic scale factor in the interpretation of MPGI which guarantee asymptotically stable position tracking. An additional term based on Sliding Mode Control is appended within GDI control to make it robust against parametric variations, disturbances and tracking performance deterioration due to generalized inversion scaling. The stability of the closed loop system is ensured by using positive definite Lyapunov energy function that guarantees semi-global practically stable position tracking. Numerical simulations are conducted on the dynamic model of rotary inverted pendulum system to analyze the efficiency of proposed RGDI control law. The comparative study is also presented, in which the performance of RGDI control is compared with Linear Quadratic Regulator (LQR) and is verified through experiments. Numerical simulations and real-time experiments demonstrate better tracking performance abilities and robustness features of RGDI control in the presence of parametric uncertainties and disturbances.Keywords: generalized dynamic inversion, lyapunov stability, rotary inverted pendulum system, sliding mode control
Procedia PDF Downloads 1701939 Nanoprecipitation with Ultrasonication for Enhancement of Oral Bioavailability of Fursemide: Pharmacokinetics and Pharmacodynamics Study in Rat Model
Authors: Malay K. Das, Bhanu P. Sahu
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Furosemide is a weakly acidic diuretic indicated for treatment of edema and hypertension. It has very poor solubility but high permeability through stomach and upper gastrointestinal tract (GIT). Due to its limited solubility it has poor and variable oral bioavailability of 10-90%. The aim of this study was to enhance the oral bioavailability of furosemide by preparation of nanosuspensions. The nanosuspensions were prepared by nanoprecipitation with sonication using DMSO (dimethyl sulfoxide) as a solvent and water as an antisolvent (NA). The prepared nanosuspensions were sterically stabilized with polyvinyl acetate (PVA).These were characterized for particle size, ζ potential, polydispersity index, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD) pattern and release behavior. The effect of nanoprecipitation on oral bioavailability of furosemide nanosuspension was studied by in vitro dissolution and in vivo absorption study in rats and compared to pure drug. The stable nanosuspension was obtained with average size range of the precipitated nanoparticles between 150-300 nm and was found to be homogenous showing a narrow polydispersity index of 0.3±0.1. DSC and XRD studies indicated that the crystalline furosemide drug was converted to amorphous form upon precipitation into nanoparticles. The release profiles of nanosuspension formulation showed up to 81.2% release in 4 h. The in vivo studies on rats revealed a significant increase in the oral absorption of furosemide in the nanosuspension compared to pure drug. The AUC0→24 and Cmax values of nanosuspension were approximately 1.38 and 1.68-fold greater than that of pure drug, respectively. Furosemide nanosuspension showed 20.06±0.02 % decrease in systolic blood pressure compared to 13.37±0.02 % in plain furosemide suspension, respectively. The improved oral bioavailability and pharmacodynamics effect of furosemide may be due to the improved dissolution of furosemide in simulated gastric fluid which results in enhanced oral systemic absorption of furosemide from stomach region where it has better permeability.Keywords: furosemide, nanosuspension, bioavailability enhancement, nanoprecipitation, oral drug delivery
Procedia PDF Downloads 5721938 Shaping and Improving the Human Resource Management in Small and Medium Enterprises in Poland
Authors: Małgorzata Smolarek
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One of the barriers to the development of small and medium-sized enterprises (SME) are difficulties connected with management of human resources. The first part of article defines the specifics of staff management in small and medium enterprises. The practical part presents results of own studies in the area of diagnosis of the state of the human resources management in small and medium-sized enterprises in Poland. It takes into account its impact on the functioning of SME in a variable environment. This part presents findings of empirical studies, which enabled verification of the hypotheses and formulation of conclusions. The findings presented in this paper were obtained during the implementation of the project entitled 'Tendencies and challenges in strategic managing SME in Silesian Voivodeship.' The aim of the studies was to diagnose the state of strategic management and human resources management taking into account its impact on the functioning of small and medium enterprises operating in Silesian Voivodeship in Poland and to indicate improvement areas of the model under diagnosis. One of the specific objectives of the studies was to diagnose the state of the process of strategic management of human resources and to identify fundamental problems. In this area, the main hypothesis was formulated: The enterprises analysed do not have comprehensive strategies for management of human resources. The survey was conducted by questionnaire. Main Research Results: Human resource management in SMEs is characterized by simplicity of procedures, and the lack of sophisticated tools and its specificity depends on the size of the company. The process of human resources management in SME has to be adjusted to the structure of an organisation, result from its objectives, so that an organisation can fully implement its strategic plans and achieve success and competitive advantage on the market. A guarantee of success is an accurately developed policy of human resources management based on earlier analyses of the existing procedures and possessed human resources.Keywords: human resources management, human resources policy, personnel strategy, small and medium enterprises
Procedia PDF Downloads 2401937 Rationale of Eye Pupillary Diameter for the UV Protection for Sunglasses
Authors: Liliane Ventura, Mauro Masili
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Ultraviolet (UV) protection is critical for sunglasses, and mydriasis, as well as miosis, are relevant parameters to consider. The literature reports that for sunglasses, ultraviolet protection is critical because sunglasses can cause the opposite effect if the lenses do not provide adequate UV protection due to the greater dilation of the pupil when wearing sunglasses. However, the scientific literature does not properly quantify to support this rationale. The reasoning may be misleading by ignoring not only the inherent absorption of UV by the sunglass lens materials but also by ignoring the absorption of the anterior structures of the eye, i.e., the cornea and aqueous humor. Therefore, we estimate the pupil diameter and calculate the solar ultraviolet influx through the pupil of the human eye for two situations of an individual wearing and not wearing sunglasses. We quantify the dilation of the pupil as a function of the luminance of the surrounding. Therefore, we calculate the influx of solar UV through the pupil of the eye for two situations for an individual wearing sunglass and for the eyes free of shade. A typical boundary condition for the calculation is an individual in an upright position wearing sunglasses, staring at the horizon as if the sun is in the zenith. The calculation was done for the latitude of the geographic center of the state of São Paulo (-22º04'11.8'' S) from sunrise to sunset. A model from the literature is used for determining the sky luminance. The initial approach is to obtain pupil diameter as a function of luminance. Therefore, as a preliminary result, we calculate the pupil diameter as a function of the time of day, as the sun moves, for a particular day of the year. The working range for luminance is daylight (10⁻⁴ – 10⁵ cd/m²). We are able to show how the pupil adjusts to brightness change (~2 - ~7.8 mm). At noon, with the sun higher, the direct incidence of light on the pupil is lower if compared to mid-morning or mid-afternoon, when the sun strikes more directly into the eye. Thus, the pupil is larger at midday. As expected, the two situations have opposite behaviors since higher luminance implies a smaller pupil. With these results, we can progress in the short term to obtain the transmittance spectra of sunglasses samples and quantify how light attenuation provided by the spectacles affects pupil diameter.Keywords: sunglasses, UV protection, pupil diameter, solar irradiance, luminance
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