Search results for: elastic light scattering spectroscopy
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6467

Search results for: elastic light scattering spectroscopy

707 Structural Characterization and Hot Deformation Behaviour of Al3Ni2/Al3Ni in-situ Core-shell intermetallic in Al-4Cu-Ni Composite

Authors: Ganesh V., Asit Kumar Khanra

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An in-situ powder metallurgy technique was employed to create Ni-Al3Ni/Al3Ni2 core-shell-shaped aluminum-based intermetallic reinforced composites. The impact of Ni addition on the phase composition, microstructure, and mechanical characteristics of the Al-4Cu-xNi (x = 0, 2, 4, 6, 8, 10 wt.%) in relation to various sintering temperatures was investigated. Microstructure evolution was extensively examined using X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), and transmission electron microscopy (TEM) techniques. Initially, under sintering conditions, the formation of "Single Core-Shell" structures was observed, consisting of Ni as the core with Al3Ni2 intermetallic, whereas samples sintered at 620°C exhibited both "Single Core-Shell" and "Double Core-Shell" structures containing Al3Ni2 and Al3Ni intermetallics formed between the Al matrix and Ni reinforcements. The composite achieved a high compressive yield strength of 198.13 MPa and ultimate strength of 410.68 MPa, with 24% total elongation for the sample containing 10 wt.% Ni. Additionally, there was a substantial increase in hardness, reaching 124.21 HV, which is 2.4 times higher than that of the base aluminum. Nanoindentation studies showed hardness values of 1.54, 4.65, 21.01, 13.16, 5.52, 6.27, and 8.39GPa corresponding to α-Al matrix, Ni, Al3Ni2, Ni and Al3Ni2 interface, Al3Ni, and their respective interfaces. Even at 200°C, it retained 54% of its room temperature strength (90.51 MPa). To investigate the deformation behavior of the composite material, experiments were conducted at deformation temperatures ranging from 300°C to 500°C, with strain rates varying from 0.0001s-1 to 0.1s-1. A sine-hyperbolic constitutive equation was developed to characterize the flow stress of the composite, which exhibited a significantly higher hot deformation activation energy of 231.44 kJ/mol compared to the self-diffusion of pure aluminum. The formation of Al2Cu intermetallics at grain boundaries and Al3Ni2/Al3Ni within the matrix hindered dislocation movement, leading to an increase in activation energy, which might have an adverse effect on high-temperature applications. Two models, the Strain-compensated Arrhenius model and the Artificial Neural Network (ANN) model, were developed to predict the composite's flow behavior. The ANN model outperformed the Strain-compensated Arrhenius model with a lower average absolute relative error of 2.266%, a smaller root means square error of 1.2488 MPa, and a higher correlation coefficient of 0.9997. Processing maps revealed that the optimal hot working conditions for the composite were in the temperature range of 420-500°C and strain rates between 0.0001s-1 and 0.001s-1. The changes in the composite microstructure were successfully correlated with the theory of processing maps, considering temperature and strain rate conditions. The uneven distribution in the shape and size of Core-shell/Al3Ni intermetallic compounds influenced the flow stress curves, leading to Dynamic Recrystallization (DRX), followed by partial Dynamic Recovery (DRV), and ultimately strain hardening. This composite material shows promise for applications in the automobile and aerospace industries.

Keywords: core-shell structure, hot deformation, intermetallic compounds, powder metallurgy

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706 Allelopathic Action of Diferents Sorghum bicolor [L.] Moench Fractions on Ipomoea grandifolia [Dammer] O'Donell

Authors: Mateus L. O. Freitas, Flávia H. de M. Libório, Letycia L. Ricardo, Patrícia da C. Zonetti, Graciene de S. Bido

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Weeds compete with agricultural crops for resources such as light, water, and nutrients. This competition can cause significant damage to agricultural producers, and, currently, the use of agrochemicals is the most effective method for controlling these undesirable plants. Morning glory (Ipomoea grandifolia [Dammer] O'Donell) is an aggressive weed and significantly reduces agricultural productivity making harvesting difficult, especially mechanical harvesting. The biggest challenge in modern agriculture is to preserve high productivity reducing environmental damage and maintaining soil characteristics. No-till is a sustainable practice that can reduce the use of agrochemicals and environmental impacts due to the presence of plant residues in the soil, which release allelopathic compounds and reduce the incidence or alter the growth and development of crops and weeds. Sorghum (Sorghum bicolor [L.] Moench) is a forage with proven allelopathic activity, mainly for producing sorgholeone. In this context, this research aimed to evaluate the allelopathic action of sorghum fractions using hexane, dichloromethane, butanol, and ethyl acetate on the germination and initial growth of morning glory. The parameters analyzed were the percentage of germination, speed of germination, seedling length, and biomass weight (fresh and dry). The bioassays were performed in Petri dishes, kept in an incubation chamber for 7 days, at 25 °C, with a 12h photoperiod. The experimental design was completely randomized, with five replicates of each treatment. The data were evaluated by analysis of variance, and the averages between each treatment were compared using the Scott Knott test at a 5% significance level. The results indicated that the dichloromethane and ethyl acetate fractions showed bioherbicidal effects, promoting effective reductions on germination and initial growth of the morning glory. It was concluded that allelochemicals were probably extracted in these fractions. These secondary metabolites can reduce the use of agrochemicals and environmental impact, making agricultural production systems more sustainable.

Keywords: allelochemicals, secondary metabolism, sorgoleone, weeds

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705 A Comparative Study of the Alternatives to Land Acquisition: India

Authors: Aparna Soni

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The much-celebrated foretold story of Indian city engines driving the growth of India has been scrutinized to have serious consequences. A wide spectrum of scholarship has brought to light the un-equalizing effects and the need to adopt a rights-based approach to development planning in India. Notably, these concepts and discourses ubiquitously entail the study of land struggles in the making of Urban. In fact, the very progression of the primitive accumulation theory to accumulation by dispossession, followed by ‘dispossession without development,’ thereafter Development without dispossession and now as Dispossession by financialization noticeably the last three developing in a span of mere three decades, is evidence enough to trace the centrality and evolving role of land in the making of urban India. India, in the last decade, has seen its regional governments actively experimenting with alternative models of land assembly (Amaravati and Delhi land pooling models, the loudly advertised ones). These are publicized as a replacement to the presumably cost and time antagonistic, prone to litigation land acquisition act of 2013. It has been observed that most of the literature treats these models as a generic large bracket of land expropriation and do not, in particular, try to differentially analyse to granularly find a pattern in these alternatives. To cater to this gap, this research comparatively studies these alternative land, assembly models. It categorises them based on their basic architecture, spatial and sectoral application, and governance frameworks. It is found that these alternatives are ad-hoc and fragmented pieces of legislation. These are fit for profit models commodifying land to ease its access by the private sector for real estate led growth. The research augments the literature on the privatization of land use planning in India. Further, it attempts to discuss the increasing role a landowner is expected to play in the future and suggests a way forward to safeguard them from market risks. The study involves a thematic analysis of the policy elements contained in legislative/policy documents, notifications, office orders. The study also derives from the various widely circulated print media information. With the present field-visit limitations, the study relies on documents accessed open-source in the public domain.

Keywords: commodification, dispossession, land acquisition, landowner

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704 An Ecological Reading of Indian Regional Literature: A Comparative Ecocritical Analysis of Punjabi Poet Shiv Kumar Batalvi and Surjit Patar's Poetry

Authors: Zameerpal Kaur

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Ecocriticism comes into existence in 1990s, it tries to explore the relationship of literature with the natural world and further it examines the role that natural surroundings and environment play in the minds of the creative writers during their imagination and creative process. The present study is an attempt to focus on the comparative ecocritical analysis of Shiv Kumar Batalvi and Surjit Patar’s selected poetry in the theoretical framework of ecocriticism in order to shed light on the poet’s vigilant views about the relationship of human life and nature. Shiv Kumar Batalvi is a renowned modern Punjabi poet. He is essentially a poet of nature and love. His opinions towards nature support his position to be considered as a major representative of recent environmental issues and ecocritical concerns in Punjabi literature. He is one of the most outstanding modern Punjabi poets, is endowed with the most artistic temperament in whose poetry nature always has a dominating existence. He seems to consciously portray the scenes of natural surroundings into his poetry; in fact the titles of his poems in themselves signify his love for the nature. Surjit Patar, an imminent modern Punjabi poet tries to present a different picture of nature into his poems; he also uses to write poems about contemporary problems. Surjit Patar’s radical quarrel with the modern cultural context makes him reject all the absolutes and finalities in the form of transcendental reason and religion, history and evolution, he freely writes about the deterioration of nature at selfish materialistic society. He is modern poet who weaves the natural imagery with the syntax of his poems. Patar’s work reflects a universal voice that is dribbled with nuanced humanism and a sense of modernity that seemed neither dated, nor trapped in regional boundaries. Through his poetry he has given a voice to the fragile, disrupting borders, disturbing the status quo. An attempt to analyse the poetic works of above said poets from ecocritical perspective as well as especially focussing on various aspects of ecocriticism like ecocentric ethics, ecoaesthetics, anthropomorphism etc. has been made throughout the comparative study of the selected works.

Keywords: anthropocentrism, degradation, environment and literature, nature

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703 Leveraging Community Partnerships for Social Impact

Authors: T. Moody, E. Mitchell, T. Dang, A. Barry, T. Proshan, S. Andrisse, V. Odero-Marah

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Women’s prison and reentry programs are focused primarily on reducing recidivism but neglect how an individual’s intersecting identities influence their risk of violence and ways that histories of gender-based violence (GBV) must be addressed for these women to recover from traumas. Light To Life (LTL) and From Prison Cells to Ph.D. (P2P) Womxn’s Cohort program recognizes this need; providing national gender-responsive programming (GRP), and trauma-informed programming to justice-impacted survivors through digital resources, leadership opportunities, educational workshops, and healing justice approaches for positive health outcomes. Through the support of a community-university partnership (CUP), a comparative evaluation study is being conducted among intimate-partner violence (IPV) survivors with histories of incarceration who have or have not participated in the cohort. The objectives of the partnership are to provide mutually beneficial training and consultation for evaluating GRP through a rigorously tested research methodology. This collaborative applies a rigorous methodology of semi-structured interviews with an intervention and control group to evaluate the impact of LTL’s programming in the P2P Womxn’s Cohort. The CUP is essential to achieve the expected results of the project. It will measure primary outcomes, including participants' level of engagement and satisfaction with programming, reduction in attitudes that accept violence in relationships, and increase in interpersonal and intrapersonal skills that lead to healthy relationships. This community-based approach will provide opportunities to evaluate the effectiveness of the program. The results addressed in the hypothesis will provide learning lessons to improve this program, to scale it up, and apply it to other similarly affected populations. The partnership experience and anticipated outcomes contribute to the knowledge in women’s health and criminal justice by fostering public awareness on the importance of developing new partnerships and fostering CUP to establish a framework to the leveraging of partnerships for social impact available to academic institutions.

Keywords: Community-university partnership, gender-responsive programming, incarceration, intimate-partner violence, POC, women

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702 Preparation and Characterization of Anti-Acne Dermal Products Based on Erythromycin β-Cyclodextrin Lactide Complex

Authors: Lacramioara Ochiuz, Manuela Hortolomei, Aurelia Vasile, Iulian Stoleriu, Marcel Popa, Cristian Peptu

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Local antibiotherapy is one of the most effective acne therapies. Erythromycin (ER) is a macrolide antibiotic topically administered for over 30 years in the form of gel, ointment or hydroalcoholic solution for the acne therapy. The use of ER as a base for topical dosage forms raises some technological challenges due to the physicochemical properties of this substance. The main disadvantage of ER is the poor water solubility (2 mg/mL) that limits both formulation using hydrophilic bases and skin permeability. Cyclodextrins (CDs) are biocompatible cyclic oligomers of glucose, with hydrophobic core and hydrophilic exterior. CDs are used to improve the bioavailability of drugs by increasing their solubility and/or their rate of dissolution after including the poorly water soluble substances (such as ER) in the hydrophobic cavity of CDs. Adding CDs leads to the increase of solubility and improved stability of the drug substance, increased permeability of substances of low water solubility, decreased toxicity and even to active dose reduction as a result of increased bioavailability. CDs increase skin tolerability by reducing the irritant effect of certain substances. We have included ER to lactide modified β-cyclodextrin, in order to improve the therapeutic effect of topically administered ER. The aims of the present study were to synthesise and describe a new complex with prolonged release of ER with lactide modified β-cyclodextrin (CD-LA_E), to investigate the CD-LA_E complex by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), to analyse the effect of semisolid base on the in vitro and ex vivo release characteristics of ER in the CD-LA_E complex by assessing the permeability coefficient and the release kinetics by fitting on mathematical models. SEM showed that, by complexation, ER changes its crystal structure and enters the amorphous phase. FTIR analysis has shown that certain specific bands of some groups in the ER structure move during the incapsulation process. The structure of the CD-LA_E complex has a molar ratio of 2.12 to 1 between lactide modified β-cyclodextrin and ER. The three semisolid bases (2% Carbopol, 13% Lutrol 127 and organogel based on Lutrol and isopropyl myristate) show a good capacity for incorporating the CD-LA_E complex, having a content of active ingredient ranging from 98.3% to 101.5% as compared to the declared value of 2% ER. The results of the in vitro dissolution test showed that the ER solubility was significantly increased by CDs incapsulation. The amount of ER released from the CD-LA_E gels was in the range of 76.23% to 89.01%, whereas gels based on ER released a maximum percentage of 26.01% ER. The ex vivo dissolution test confirms the increased ER solubility achieved by complexation, and supports the assumption that the use of this process might increase ER permeability. The highest permeability coefficient was obtained in ER released from gel based on 2% Carbopol: in vitro 33.33 μg/cm2/h, and ex vivo 26.82 μg/cm2/h, respectively. The release kinetics of complexed ER is performed by Fickian diffusion, according to the results obtained by fitting the data in the Korsmeyer-Peppas model.

Keywords: erythromycin, acne, lactide, cyclodextrin

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701 Upon Poly(2-Hydroxyethyl Methacrylate-Co-3, 9-Divinyl-2, 4, 8, 10-Tetraoxaspiro (5.5) Undecane) as Polymer Matrix Ensuring Intramolecular Strategies for Further Coupling Applications

Authors: Aurica P. Chiriac, Vera Balan, Mihai Asandulesa, Elena Butnaru, Nita Tudorachi, Elena Stoleru, Loredana E. Nita, Iordana Neamtu, Alina Diaconu, Liliana Mititelu-Tartau

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The interest for studying ‘smart’ materials is entirely justified and in this context were realized investigations on poly(2-hydroxyethylmethacrylate-co-3, 9-divinyl-2, 4, 8, 10-tetraoxaspiro (5.5) undecane), which is a macromolecular compound with sensibility at pH and temperature, gel formation capacity, binding properties, amphilicity, good oxidative and thermal stability. Physico-chemical characteristics in terms of the molecular weight, temperature-sensitive abilities and thermal stability, as well rheological, dielectric and spectroscopic properties were evaluated in correlation with further coupling capabilities. Differential scanning calorimetry investigation indicated Tg at 36.6 °C and a melting point at Tm=72.8°C, for the studied copolymer, and up to 200oC two exothermic processes (at 99.7°C and 148.8°C) were registered with losing weight of about 4 %, respective 19.27%, which indicate just processes of thermal decomposition (and not phenomena of thermal transition) owing to scission of the functional groups and breakage of the macromolecular chains. At the same time, the rheological studies (rotational tests) confirmed the non-Newtonian shear-thinning fluid behavior of the copolymer solution. The dielectric properties of the copolymer have been evaluated in order to investigate the relaxation processes and two relaxation processes under Tg value were registered and attributed to localized motions of polar groups from side chain macromolecules, or parts of them, without disturbing the main chains. According to literature and confirmed as well by our investigations, β-relaxation is assigned with the rotation of the ester side group and the γ-relaxation corresponds to the rotation of hydroxy- methyl side groups. The fluorescence spectroscopy confirmed the copolymer structure, the spiroacetal moiety getting an axial conformation, more stable, with lower energy, able for specific interactions with molecules from environment, phenomena underlined by different shapes of the emission spectra of the copolymer. Also, the copolymer was used as template for indomethacin incorporation as model drug, and the biocompatible character of the complex was confirmed. The release behavior of the bioactive compound was dependent by the copolymer matrix composition, the increasing of 3, 9-divinyl-2, 4, 8, 10-tetraoxaspiro (5.5) undecane comonomer amount attenuating the drug release. At the same time, the in vivo studies did not show significant differences of leucocyte formula elements, GOT, GPT and LDH levels, nor immune parameters (OC, PC, and BC) between control mice group and groups treated just with copolymer samples, with or without drug, data attesting the biocompatibility of the polymer samples. The investigation of the physico-chemical characteristics of poly(2-hydrxyethyl methacrylate-co-3, 9-divinyl-2, 4, 8, 10-tetraoxaspiro (5.5) undecane) in terms of temperature-sensitive abilities, rheological and dielectrical properties, are bringing useful information for further specific use of this polymeric compound.

Keywords: bioapplications, dielectric and spectroscopic properties, dual sensitivity at pH and temperature, smart materials

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700 Development of an Artificial Neural Network to Measure Science Literacy Leveraging Neuroscience

Authors: Amanda Kavner, Richard Lamb

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Faster growth in science and technology of other nations may make staying globally competitive more difficult without shifting focus on how science is taught in US classes. An integral part of learning science involves visual and spatial thinking since complex, and real-world phenomena are often expressed in visual, symbolic, and concrete modes. The primary barrier to spatial thinking and visual literacy in Science, Technology, Engineering, and Math (STEM) fields is representational competence, which includes the ability to generate, transform, analyze and explain representations, as opposed to generic spatial ability. Although the relationship is known between the foundational visual literacy and the domain-specific science literacy, science literacy as a function of science learning is still not well understood. Moreover, the need for a more reliable measure is necessary to design resources which enhance the fundamental visuospatial cognitive processes behind scientific literacy. To support the improvement of students’ representational competence, first visualization skills necessary to process these science representations needed to be identified, which necessitates the development of an instrument to quantitatively measure visual literacy. With such a measure, schools, teachers, and curriculum designers can target the individual skills necessary to improve students’ visual literacy, thereby increasing science achievement. This project details the development of an artificial neural network capable of measuring science literacy using functional Near-Infrared Spectroscopy (fNIR) data. This data was previously collected by Project LENS standing for Leveraging Expertise in Neurotechnologies, a Science of Learning Collaborative Network (SL-CN) of scholars of STEM Education from three US universities (NSF award 1540888), utilizing mental rotation tasks, to assess student visual literacy. Hemodynamic response data from fNIRsoft was exported as an Excel file, with 80 of both 2D Wedge and Dash models (dash) and 3D Stick and Ball models (BL). Complexity data were in an Excel workbook separated by the participant (ID), containing information for both types of tasks. After changing strings to numbers for analysis, spreadsheets with measurement data and complexity data were uploaded to RapidMiner’s TurboPrep and merged. Using RapidMiner Studio, a Gradient Boosted Trees artificial neural network (ANN) consisting of 140 trees with a maximum depth of 7 branches was developed, and 99.7% of the ANN predictions are accurate. The ANN determined the biggest predictors to a successful mental rotation are the individual problem number, the response time and fNIR optode #16, located along the right prefrontal cortex important in processing visuospatial working memory and episodic memory retrieval; both vital for science literacy. With an unbiased measurement of science literacy provided by psychophysiological measurements with an ANN for analysis, educators and curriculum designers will be able to create targeted classroom resources to help improve student visuospatial literacy, therefore improving science literacy.

Keywords: artificial intelligence, artificial neural network, machine learning, science literacy, neuroscience

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699 Spatio-Temporal Land Cover Changes Monitoring Using Remotely Sensed Techniques in Riyadh Region, KSA

Authors: Abdelrahman Elsehsah

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Land Use and Land Cover (LULC) dynamics in Riyadh over a decade were comprehensively analyzed using the Google Earth Engine (GEE) platform. By harnessing the Landsat 8 Image collection and night-time light image collection from May to August for the years 2013 and 2023, we were able to generate insightful datasets capturing the changing landscape of the region. Our approach involved a Random Forest (RF) classification model that consistently displayed commendable precision scores above 92% for both years. A notable discovery from the study was the pronounced urban expansion, particularly around Riyadh city. Within a mere ten-year span, urbanization surged noticeably, affecting the broader ecological environment of the region. Interestingly, the northeastern part of Riyadh emerged as a focal point of this growth, signaling rapid urban growth of urban sprawl and development. A comparison between the two years indicates a 21.51% increase in built-up areas, revealing the transformative pace of urban sprawl. Contrastingly, vegetation cover patterns presented a more nuanced picture. While our initial hypothesis predicted a decline in vegetation, the actual findings depicted both vegetation reduction in certain pockets and new growth in others, resulting in an overall 25.89% increase. This intricate pattern might be attributed to shifting agricultural practices, afforestation efforts, or even satellite image timings not aligning with seasonal vegetation growth. The bare soil, predominant in the desert landscape of Riyadh, saw a marginal reduction of 0.37% over the decade, challenging our initial expectations. Urban and agricultural advancements in Saudi Arabia appear to have slightly reduced the expanse of barren terrains. This study, underpinned by a rigorous methodological framework, reveals the multifaceted land cover changes in Riyadh in response to urban development and environmental factors. The precise, data-driven insights provided by our analysis serve as invaluable tools for understanding urban growth trajectories, guiding urban planning, policy formulation, and sustainable development endeavors in the region.

Keywords: remote sensing, KSA, ArcGIS, spatio-temporal

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698 Pakistan’s Counterinsurgency Operations: A Case Study of Swat

Authors: Arshad Ali

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The Taliban insurgency in Swat which started apparently as a social movement in 2004 transformed into an anti-Pakistan Islamist insurgency by joining hands with the Tehrik-e-Taliban Pakistan (TTP) upon its formation in 2007. It quickly spread beyond Swat by 2009 making Swat the second stronghold of TTP after FATA. It prompted the Pakistan military to launch a full-scale counterinsurgency military operation code named Rah-i-Rast to regain the control of Swat. Operation Rah-i-Rast was successful not only in restoring the writ of the State but more importantly in creating a consensus against the spread of Taliban insurgency in Pakistan at political, social and military levels. This operation became a test case for civilian government and military to seek for a sustainable solution combating the TTP insurgency in the north-west of Pakistan. This study analyzes why the counterinsurgency operation Rah-i-Rast was successful and why the previous ones came into failure. The study also explores factors which created consensus against the Taliban insurgency at political and social level as well as reasons which hindered such a consensual approach in the past. The study argues that the previous initiatives failed due to various factors including Pakistan army’s lack of comprehensive counterinsurgency model, weak political will and public support, and states negligence. Also, the initial counterinsurgency policies were ad-hoc in nature fluctuating between military operations and peace deals. After continuous failure, the military revisited its approach to counterinsurgency in the operation Rah-i-Rast. The security forces learnt from their past experiences and developed a pragmatic counterinsurgency model: ‘clear, hold, build, and transfer.’ The military also adopted the population-centric approach to provide security to the local people. This case Study of Swat evaluates the strengths and weaknesses of the Pakistan's counterinsurgency operations as well as peace agreements. It will analyze operation Rah-i-Rast in the light of David Galula’s model of counterinsurgency. Unlike existing literature, the study underscores the bottom up approach adopted by the Pakistan’s military and government by engaging the local population to sustain the post-operation stability in Swat. More specifically, the study emphasizes on the hybrid counterinsurgency model “clear, hold, and build and Transfer” in Swat.

Keywords: Insurgency, Counterinsurgency, clear, hold, build, transfer

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697 Challenges and Prospects of Preservation of Tangible Cultural Heritage Management: A Case Study in Lake Tana Islands, Ethiopia

Authors: Ayele Tamene

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Cultural heritage is the legacy of physical artifacts and intangible attributes of a group or society that are inherited from past generations, maintained in the present and bestowed for the benefit of future generations. Tangible heritage e includes buildings and historic places, monuments, artifacts, etc., which are considered worthy of preservation for the future. These include objects significant to the archaeology, architecture, science or technology of a specific culture. The research addressed the challenges and prospects of preservation of tangible cultural heritage management in Lake Tana islands; Amahara Regional State. Specifically, the research inquired the major factors which affected tangible cultural heritage management, investigated how communities successfully involved in tangible cultural heritage management, and described the contribution of cultural management to tourism development. It employed qualitative research approaches to grasp the existing condition in the study area. Major techniques of data gathering such as in-depth interview, observation/photographing and Focus Group Discussion (FGDs) were used. Related documents collected through secondary sources were examined and analyzed. In Lake Tana Islands precious heritages such as ancient religious manuscripts (written since 9th century), sacral wall paintings, gold and silver Crosses, crowns and prestigious clothes of the various kings of the medieval and the 19th century are found. The study indicated that heritages in Tana islands were affected by both natural and manmade problems. In Lake Tana Islands, movable heritages were looted several times by foreign aggressors, tourists, and local people who serve there. Some heritages were affected by visitors by their camera flash light and hand touch. Most heritages in the Tana islands lacked community ownership and preserved non- professionally which highly affected their originality and authenticity. Therefore, the local community and the regional government should work together in the preservation of these heritage sites and enhance their role for socio-economic development as a center of research and tourist destinations.

Keywords: cultural heritages, heritage preservation, lake Tana heritages, non professional preservation tangible heritages

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696 Displaced People in International Marriage Law: Choice of Law and the 1951 Convention Relating to the Status of Refugees

Authors: Rorick Daniel Tovar Galvan

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The 1951 Convention relating to the status of refugees contains a conflict of law rule for the determination of the applicable law to marriage. The wording of this provision leaves much to be desired as it uses the domicile and the residence of the spouses as single main and subsidiary connecting factors. In cases where couples live in different countries, the law applicable to the case is unclear. The same problem arises when refugees are married to individuals outside of the convention’s scope of application. Different interpretations of this legal provision have arisen to solve this problem. Courts in a number of European countries apply the so-called modification doctrine: states should apply their domestic private international rules in all cases involving refugees. Courts shall, however, replace the national connecting factor by the domicile or residence in situations where nationality is used to determine the applicable law. The internal conflict of law rule will then be slightly modified in order to be applied according to the convention. However, this approach excludes these people from using their national law if they so desire. As nationality is, in all cases, replaced by domicile or residence as connecting factor, refugees are automatically deprived of the possibility to choose this law in jurisdictions that include the party autonomy in international marriage law. This contribution aims to shed light on the international legal framework applicable to marriages celebrated by refugees and the unnecessary restrictions to the exercise of the party autonomy these individuals are subjected to. The interest is motivated by the increasing number of displaced people, the significant number of states party to the Refugee Convention – approximately 150 – and the fact that more and more countries allow choice of law agreements in marriage law. Based on a study of German, Spanish and Swiss case law, the current practices in Europe, as well as some incoherencies derived from the current interpretation of the convention, will be discussed. The main objective is showing that there is neither an economic nor a legal basis to deny refugees the right to choose the law of their country of origin in those jurisdictions providing for this possibility to other foreigners. Quite the contrary, after analyzing other provisions contained in the conventions, this restriction would mean a contravention of other obligations included in the text.

Keywords: choice of law, conflict of laws, international marriage law, refugees

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695 Implementing Lesson Study in Qatari Mathematics Classroom: A Case Study of a New Experience for Teachers through IMPULS-QU Lesson Study Program

Authors: Areej Isam Barham

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The implementation of Japanese lesson study approach in the mathematics classroom has been grown worldwide as a model of professional development for teachers. In Qatar, the implementation of IMPULS-QU lesson study program aimed to establish a robust organizational improvement model of professional development for mathematics teachers in Qatar schools. This study describes the implementation of a lesson study model at Al-Markhyia Independent Primary School through different stages; and discusses how the planning process, the research lesson, and the post discussion participates in providing teachers and researchers with a successful research lesson for teacher professional development. The research followed a case study approach in one mathematics classroom. Two teachers and one professional development specialist participated the planning process. One teacher conducted the research lesson study by introducing a problem solving related to the concept of the ‘Mean’ in a mathematics class, 21 students in grade 6 participated in solving the mathematic problem, 11 teachers, 4 professional development specialists, and 4 mathematics professors observed the research lesson. All previous participants except the students participated in a pre and post-lesson discussion within this research. This study followed a qualitative research approach by analyzing the collected data through different stages in the research lesson study. Observation, field notes, and semi-structured interviews conducted to collect data to achieve the research aims. One feature of this lesson study research is that this research describes the implementation for a lesson study as a new experience for one mathematics teacher and 21 students after 3 years of conducting IMPULS-QU project in Al-Markhyia school. The research describes various stages through the implementation of this lesson study model starting from the planning process and ending by the post discussion process. Findings of the study also address the impact of lesson study approach in teaching mathematics for the development of teachers from their point views. Results of the study show the benefits of using lesson study from the point views of participated teachers, theory perceptions about the essential features of lesson study, and their needs for future development. The discussion of the study addresses different features and issues related to the implementation of IMPULS-QU lesson study model in the mathematics classroom. In the light of the study, the research presents recommendations and suggestions for future professional development.

Keywords: lesson study, mathematics education, mathematics teaching experience, teacher professional development

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694 From Theory to Practice: Harnessing Mathematical and Statistical Sciences in Data Analytics

Authors: Zahid Ullah, Atlas Khan

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The rapid growth of data in diverse domains has created an urgent need for effective utilization of mathematical and statistical sciences in data analytics. This abstract explores the journey from theory to practice, emphasizing the importance of harnessing mathematical and statistical innovations to unlock the full potential of data analytics. Drawing on a comprehensive review of existing literature and research, this study investigates the fundamental theories and principles underpinning mathematical and statistical sciences in the context of data analytics. It delves into key mathematical concepts such as optimization, probability theory, statistical modeling, and machine learning algorithms, highlighting their significance in analyzing and extracting insights from complex datasets. Moreover, this abstract sheds light on the practical applications of mathematical and statistical sciences in real-world data analytics scenarios. Through case studies and examples, it showcases how mathematical and statistical innovations are being applied to tackle challenges in various fields such as finance, healthcare, marketing, and social sciences. These applications demonstrate the transformative power of mathematical and statistical sciences in data-driven decision-making. The abstract also emphasizes the importance of interdisciplinary collaboration, as it recognizes the synergy between mathematical and statistical sciences and other domains such as computer science, information technology, and domain-specific knowledge. Collaborative efforts enable the development of innovative methodologies and tools that bridge the gap between theory and practice, ultimately enhancing the effectiveness of data analytics. Furthermore, ethical considerations surrounding data analytics, including privacy, bias, and fairness, are addressed within the abstract. It underscores the need for responsible and transparent practices in data analytics, and highlights the role of mathematical and statistical sciences in ensuring ethical data handling and analysis. In conclusion, this abstract highlights the journey from theory to practice in harnessing mathematical and statistical sciences in data analytics. It showcases the practical applications of these sciences, the importance of interdisciplinary collaboration, and the need for ethical considerations. By bridging the gap between theory and practice, mathematical and statistical sciences contribute to unlocking the full potential of data analytics, empowering organizations and decision-makers with valuable insights for informed decision-making.

Keywords: data analytics, mathematical sciences, optimization, machine learning, interdisciplinary collaboration, practical applications

Procedia PDF Downloads 94
693 A Review of Toxic and Non-Toxic Cyanobacteria Species Occurrence in Water Supplies Destined for Maize Meal Production Process: A Case Study of Vhembe District

Authors: M. Mutoti, J. Gumbo, A. Jideani

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Cyanobacteria or blue green algae have been part of the human diet for thousands of years. Cyanobacteria can multiply quickly in surface waters and form blooms when favorable conditions prevail, such as high temperature, intense light, high pH, and increased availability of nutrients, especially phosphorous and nitrogen, artificially released by anthropogenic activities. Consumption of edible cyanotoxins such as Spirulina may reduce risks of cataracts and age related macular degeneration. Sulfate polysaccharides exhibit antitumor, anticoagulant, anti-mutagenic, anti-inflammatory, antimicrobial, and even antiviral activity against HIV, herpes, and hepatitis. In humans, exposure to cyanotoxins can occur in various ways; however, the oral route is the most important. This is mainly through drinking water, or by eating contaminated foods; it may even involve ingesting water during recreational activities. This paper seeks to present a review on cyanobacteria/cyanotoxin contamination of water and food and implications for human health. In particular, examining the water quality used during maize seed that passes through mill grinding processes. In order to fulfil the objective, this paper starts with the theoretical framework on cyanobacteria contamination of food that will guide review of the present paper. A number of methods for decontaminating cyanotoxins in food is currently available. Therefore, physical, chemical, and biological methods for treating cyanotoxins are reviewed and compared. Furthermore, methods that are utilized for detecting and identifying cyanobacteria present in water and food were also informed in this review. This review has indicated various routes through which humans can be exposed to cyanotoxins. Accumulation of cyanotoxins, mainly microcystins, in food has raised an awareness of the importance of food as microcystins exposure route to human body. Therefore, this review demonstrates the importance of expanding research on cyanobacteria/cyanotoxin contamination of water and food for water treatment and water supply management, with focus on examining water for domestic use. This will help providing information regarding the prevention or minimization of contamination of water and food, and also reduction or removal of contamination through treatment processes and prevention of recontamination in the distribution system.

Keywords: biofilm, cyanobacteria, cyanotoxin, food contamination

Procedia PDF Downloads 162
692 Inflammatory Changes Caused by Lipopolysaccharide in Odontoblasts

Authors: Virve Pääkkönen, Heidi M. Cuffaro, Leo Tjäderhane

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Objectives: Odontoblasts are the outermost cell layer of dental pulp and form the dentin. Importance of bacterial products, e.g. lipoteichoic acid (LTA), a cell wall component of Gram-positive bacteria and lipopolysaccharide (LPS), a cell wall component of Gram-negative bacteria, have been indicated in the pathogenesis of pulpitis. Gram-positive bacteria are more prevalent in superficial carious lesion while the amount gram-negative is higher in the deep lesions. Objective of this study was to investigate the effect of these bacterial products on inflammatory response of pulp tissue. Interleukins (IL) were of special interest. Various ILs have been observed in the dentin-pulp complex of carious tooth in vivo. Methods: Tissue culture method was used for testing the effect of LTA and LPS on human odontoblasts. Enzymatic isolation technique was used to extract living odontoblasts for cell cultures. DNA microarray and quantitative PCR (qPCR) were used to characterize the changes in the expression profile of the tissue cultured odontoblasts. Laser microdissection was used to cut healthy and affected dentin and odontoblast layer directly under carious lesion for experiments. Cytokine array detecting 80 inflammatory cytokines was used to analyze the protein content of conditioned culture media as well as dentin and odontoblasts from the carious teeth. Results: LPS caused increased gene expression IL-1α, and -8 and decrease of IL-1β, 12 , -15 and -16 after 1h treatment, while after 24h treatment decrease of IL-8, -11 and 23 mRNAs was observed. LTA treatment caused cell death in the tissue cultured odontoblasts but in in the cell culture but not in cell culture. Cytokine array revealed at least 2-fold down-regulation of IL-1β, -10 and -12 in response to LPS treatment. Cytokine array of odontoblasts of carious teeth, as well as LPS-treated tissue-cultured odontoblasts, revealed increased protein amounts of IL-16, epidermal growth factor (EGF), angiogenin and IGFBP-1 as well as decreased amount of fractalkine. In carious dentin, increased amount of IL-1β, EGF and fractalkine was observed, as well as decreased level of GRO-1 and HGF. Conclusion: LPS caused marked changes in the expression of inflammatory cytokines in odontoblasts. Similar changes were observed in the odontoblasts cut directly under the carious lesion. These results help to shed light on the inflammatory processes happening during caries.

Keywords: inflammation, interleukin, lipoteichoic acid, odontoblasts

Procedia PDF Downloads 211
691 Tailoring Structural, Thermal and Luminescent Properties of Solid-State MIL-53(Al) MOF via Fe³⁺ Cation Exchange

Authors: T. Ul Rehman, S. Agnello, F. M. Gelardi, M. M. Calvino, G. Lazzara, G. Buscarino, M. Cannas

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Metal-Organic Frameworks (MOFs) have emerged as promising candidates for detecting metal ions owing to their large surface area, customizable porosity, and diverse functionalities. In recent years, there has been a surge in research focused on MOFs with luminescent properties. These frameworks are constructed through coordinated bonding between metal ions and multi-dentate ligands, resulting in inherent fluorescent structures. Their luminescent behavior is influenced by factors like structural composition, surface morphology, pore volume, and interactions with target analytes, particularly metal ions. MOFs exhibit various sensing mechanisms, including photo-induced electron transfer (PET) and charge transfer processes such as ligand-to-metal (LMCT) and metal-to-ligand (MLCT) transitions. Among these, MIL-53(Al) stands out due to its flexibility, stability, and specific affinity towards certain metal ions, making it a promising platform for selective metal ion sensing. This study investigates the structural, thermal, and luminescent properties of MIL-53(Al) metal-organic framework (MOF) upon Fe3+ cation exchange. Two separate sets of samples were prepared to activate the MOF powder at different temperatures. The first set of samples, referred to as MIL-53(Al), activated (120°C), was prepared by activating the raw powder in a glass tube at 120°C for 12 hours and then sealing it. The second set of samples, referred to as MIL-53(Al), activated (300°C), was prepared by activating the MIL-53(Al) powder in a glass tube at 300°C for 70 hours. Additionally, 25 mg of MIL-53(Al) powder was dispersed in 5 mL of Fe3+ solution at various concentrations (0.1-100 mM) for the cation exchange experiment. The suspension was centrifuged for five minutes at 10,000 rpm to extract MIL-53(Al) powder. After three rounds of washing with ultrapure water, MIL-53(Al) powder was heated at 120°C for 12 hours. For PXRD and TGA analyses, a sample of the obtained MIL-53(Al) was used. We also activated the cation-exchanged samples for time-resolved photoluminescence (TRPL) measurements at two distinct temperatures (120 and 300°C) for comparative analysis. Powder X-ray diffraction patterns reveal amorphization in samples with higher Fe3+ concentrations, attributed to alterations in coordination environments and ion exchange dynamics. Thermal decomposition analysis shows reduced weight loss in Fe3+-exchanged MOFs, indicating enhanced stability due to stronger metal-ligand bonds and altered decomposition pathways. Raman spectroscopy demonstrates intensity decrease, shape disruption, and frequency shifts, indicative of structural perturbations induced by cation exchange. Photoluminescence spectra exhibit ligand-based emission (π-π* or n-π*) and ligand-to-metal charge transfer (LMCT), influenced by activation temperature and Fe3+ incorporation. Quenching of luminescence intensity and shorter lifetimes upon Fe3+ exchange result from structural distortions and Fe3+ binding to organic linkers. In a nutshell, this research underscores the complex interplay between composition, structure, and properties in MOFs, offering insights into their potential for diverse applications in catalysis, gas storage, and luminescent devices.

Keywords: Fe³⁺ cation exchange, luminescent metal-organic frameworks (LMOFs), MIL-53(Al), solid-state analysis

Procedia PDF Downloads 66
690 Effects of Mild Heat Treatment on the Physical and Microbial Quality of Salak Apricot Cultivar

Authors: Bengi Hakguder Taze, Sevcan Unluturk

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Şalak apricot (Prunus armeniaca L., cv. Şalak) is a specific variety grown in Igdir, Turkey. The fruit has distinctive properties distinguish it from other cultivars, such as its unique size, color, taste and higher water content. Drying is the widely used method for preservation of apricots. However, fresh consumption is preferred for Şalak apricot instead of drying due to its low dry matter content. Higher amounts of water in the structure and climacteric nature make the fruit sensitive against rapid quality loss during storage. Hence, alternative processing methods need to be introduced to extend the shelf life of the fresh produce. Mild heat (MH) treatment is of great interest as it can reduce the microbial load and inhibit enzymatic activities. Therefore, the aim of this study was to evaluate the impact of mild heat treatment on the natural microflora found on Şalak apricot surfaces and some physical quality parameters of the fruit, such as color and firmness. For this purpose, apricot samples were treated at different temperatures between 40 and 60 ℃ for different periods ranging between 10 to 60 min using a temperature controlled water bath. Natural flora on the fruit surfaces was examined using standard plating technique both before and after the treatment. Moreover, any changes in color and firmness of the fruit samples were also monitored. It was found that control samples were initially containing 7.5 ± 0.32 log CFU/g of total aerobic plate count (TAPC), 5.8±0.31 log CFU/g of yeast and mold count (YMC), and 5.17 ± 0.22 log CFU/g of coliforms. The highest log reductions in TAPC and YMC were observed as 3.87-log and 5.8-log after the treatments at 60 ℃ and 50 ℃, respectively. Nevertheless, the fruit lost its characteristic aroma at temperatures above 50 ℃. Furthermore, great color changes (ΔE ˃ 6) were observed and firmness of the apricot samples was reduced at these conditions. On the other hand, MH treatment at 41 ℃ for 10 min resulted in 1.6-log and 0.91-log reductions in TAPC and YMC, respectively, with slightly noticeable changes in color (ΔE ˂ 3). In conclusion, application of temperatures higher than 50 ℃ caused undesirable changes in physical quality of Şalak apricots. Although higher microbial reductions were achieved at those temperatures, temperatures between 40 and 50°C should be further investigated considering the fruit quality parameters. Another strategy may be the use of high temperatures for short time periods not exceeding 1-5 min. Besides all, MH treatment with UV-C light irradiation can be also considered as a hurdle strategy for better inactivation results.

Keywords: color, firmness, mild heat, natural flora, physical quality, şalak apricot

Procedia PDF Downloads 137
689 Investigation of a Novel Dual Band Microstrip/Waveguide Hybrid Antenna Element

Authors: Raoudane Bouziyan, Kawser Mohammad Tawhid

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Microstrip antennas are low in profile, light in weight, conformable in structure and are now developed for many applications. The main difficulty of the microstrip antenna is its narrow bandwidth. Several modern applications like satellite communications, remote sensing, and multi-function radar systems will find it useful if there is dual-band antenna operating from a single aperture. Some applications require covering both transmitting and receiving frequency bands which are spaced apart. Providing multiple antennas to handle multiple frequencies and polarizations becomes especially difficult if the available space is limited as with airborne platforms and submarine periscopes. Dual band operation can be realized from a single feed using slot loaded or stacked microstrip antenna or two separately fed antennas sharing a common aperture. The former design, when used in arrays, has certain limitations like complicated beam forming or diplexing network and difficulty to realize good radiation patterns at both the bands. The second technique provides more flexibility with separate feed system as beams in each frequency band can be controlled independently. Another desirable feature of a dual band antenna is easy adjustability of upper and lower frequency bands. This thesis presents investigation of a new dual-band antenna, which is a hybrid of microstrip and waveguide radiating elements. The low band radiator is a Shorted Annular Ring (SAR) microstrip antenna and the high band radiator is an aperture antenna. The hybrid antenna is realized by forming a waveguide radiator in the shorted region of the SAR microstrip antenna. It is shown that the upper to lower frequency ratio can be controlled by the proper choice of various dimensions and dielectric material. Operation in both linear and circular polarization is possible in either band. Moreover, both broadside and conical beams can be generated in either band from this antenna element. Finite Element Method based software, HFSS and Method of Moments based software, FEKO were employed to perform parametric studies of the proposed dual-band antenna. The antenna was not tested physically. Therefore, in most cases, both HFSS and FEKO were employed to corroborate the simulation results.

Keywords: FEKO, HFSS, dual band, shorted annular ring patch

Procedia PDF Downloads 402
688 Optimizing PharmD Education: Quantifying Curriculum Complexity to Address Student Burnout and Cognitive Overload

Authors: Frank Fan

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PharmD (Doctor of Pharmacy) education has confronted an increasing challenge — curricular overload, a phenomenon resulting from the expansion of curricular requirements, as PharmD education strives to produce graduates who are practice-ready. The aftermath of the global pandemic has amplified the need for healthcare professionals, leading to a growing trend of assigning more responsibilities to them to address the global healthcare shortage. For instance, the pharmacist’s role has expanded to include not only compounding and distributing medication but also providing clinical services, including minor ailments management, patient counselling and vaccination. Consequently, PharmD programs have responded by continually expanding their curricula adding more requirements. While these changes aim to enhance the education and training of future professionals, they have also led to unintended consequences, including curricular overload, student burnout, and a potential decrease in program quality. To address the issue and ensure program quality, there is a growing need for evidence-based curriculum reforms. My research seeks to integrate Cognitive Load Theory, emerging machine learning algorithms within artificial intelligence (AI), and statistical approaches to develop a quantitative framework for optimizing curriculum design within the PharmD program at the University of Toronto, the largest PharmD program within Canada, to provide quantification and measurement of issues that currently are only discussed in terms of anecdote rather than data. This research will serve as a guide for curriculum planners, administrators, and educators, aiding in the comprehension of how the pharmacy degree program compares to others within and beyond the field of pharmacy. It will also shed light on opportunities to reduce the curricular load while maintaining its quality and rigor. Given that pharmacists constitute the third-largest healthcare workforce, their education shares similarities and challenges with other health education programs. Therefore, my evidence-based, data-driven curriculum analysis framework holds significant potential for training programs in other healthcare professions, including medicine, nursing, and physiotherapy.

Keywords: curriculum, curriculum analysis, health professions education, reflective writing, machine learning

Procedia PDF Downloads 62
687 Impact of the Oxygen Content on the Optoelectronic Properties of the Indium-Tin-Oxide Based Transparent Electrodes for Silicon Heterojunction Solar Cells

Authors: Brahim Aissa

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Transparent conductive oxides (TCOs) used as front electrodes in solar cells must feature simultaneously high electrical conductivity, low contact resistance with the adjacent layers, and an appropriate refractive index for maximal light in-coupling into the device. However, these properties may conflict with each other, motivating thereby the search for TCOs with high performance. Additionally, due to the presence of temperature sensitive layers in many solar cell designs (for example, in thin-film silicon and silicon heterojunction (SHJ)), low-temperature deposition processes are more suitable. Several deposition techniques have been already explored to fabricate high-mobility TCOs at low temperatures, including sputter deposition, chemical vapor deposition, and atomic layer deposition. Among this variety of methods, to the best of our knowledge, magnetron sputtering deposition is the most established technique, despite the fact that it can lead to damage of underlying layers. The Sn doped In₂O₃ (ITO) is the most commonly used transparent electrode-contact in SHJ technology. In this work, we studied the properties of ITO thin films grown by RF sputtering. Using different oxygen fraction in the argon/oxygen plasma, we prepared ITO films deposited on glass substrates, on one hand, and on a-Si (p and n-types):H/intrinsic a-Si/glass substrates, on the other hand. Hall Effect measurements were systematically conducted together with total-transmittance (TT) and total-reflectance (TR) spectrometry. The electrical properties were drastically affected whereas the TT and TR were found to be slightly impacted by the oxygen variation. Furthermore, the time of flight-secondary ion mass spectrometry (TOF-SIMS) technique was used to determine the distribution of various species throughout the thickness of the ITO and at various interfaces. The depth profiling of indium, oxygen, tin, silicon, phosphorous, boron and hydrogen was investigated throughout the various thicknesses and interfaces, and obtained results are discussed accordingly. Finally, the extreme conditions were selected to fabricate rear emitter SHJ devices, and the photovoltaic performance was evaluated; the lower oxygen flow ratio was found to yield the best performance attributed to lower series resistance.

Keywords: solar cell, silicon heterojunction, oxygen content, optoelectronic properties

Procedia PDF Downloads 159
686 Metformin and Its Combination with Sodium Hydrosulfide Influences Plasma Galectin-3 and CSE/H₂S System in Diabetic Rat's Heart

Authors: I. V. Palamarchuk, N. V. Zaichko

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Background and Aims: Galectin-3 is a marker of subclinical cardiac injury and is elevated in individuals with type 2 diabetes mellitus; while hydrogen sulfide (H₂S), metabolite of sulfur-containing amino acids, is considered having antifibrogenic effects. This study was designed to investigate whether metformin and its combination with NaHS can influence plasma galectin-3 and cystathionine-γ-lyase/hydrogen sulfide (CSE/H₂S) system in diabetic rat’s heart. Methods: 32 healthy male rats (180-250 g) were divided into 4 groups. To induct diabetes, rats (group 2-4) were injected with streptozotocin (STZ, 40 mg/kg/i.p., 0.1 M citrate buffer (pH 4.5). Rats from 3d (STZ+Metf) and 4th (STZ+Metf+NaHS) groups were given metformin (500 mg/kg/day) orally, and rats from 4th (STZ+Metf+NaHS) group were injected sodium hydrosulfide (NaHS, 3 mg/kg/i.p.) once per day starting from 3 to 28 day after streptozotocin injection. Rats of first group (control) were administered the equivalent volumes of 0.9% NaCl. Plasma galectin-3 was measured by ELISA. Rats’ hearts were sampled for determination of H2S by reaction with N,N-Dimethyl-p-phenylenediamine. Determination of CSE gene expression was performed in real time using PCR in the presence of SYBR Green I, using DT-Light detecting amplifier ('DNA-technology', Russia). Results: Induction of streptozotocin diabetes (STZ-diabetes, group 2) was followed by low myocardial H2S concentration and CSE expression (by 35%, p < 0.05 and 60.5%, p < 0.001 respectively, than that in controls), while plasma galectin-3 in this group was significantly higher than in controls (by 3.8 times, p < 0.05). Administration of metformin (group 3) resulted in significantly higher H₂S concentration (by 28.5%, p < 0.05), whereas CSE expression was only by 6% more than that in STZ-diabetes, as well as plasma galectin-3 was only by 14.8% lower in comparison with untreated diabetic rats. The inhibition of H₂S generation and CSE activity by diabetes was greatly attenuated in STZ+Metf+NaHS group. The combination of metformin with NaHS significantly stimulated H₂S production (by 48%, p < 0.05 and 15%, p < 0.05 more than STZ-diabetes and STZ+Metf respectively) and CSE gene expression (by 64.8%, p < 0.05 compared to STZ-diabetes and by 55.4%,p < 0.05 compared to STZ+Metf). Besides, plasma galectin-3 in rats receiving metformin and NaHS was significantly lower by 42%, p < 0.05 and 32.5%, p < 0.05 compared to STZ-diabetes and STZ+Metf groups respectively. Conclusions: To summarize, dysfunction of CSE/H2S system and galectin-3 stimulation was found in streptozotocin-induced diabetic rats. Metformin and its combination with exogenous H2S effectively prevented the development of metabolic changes induced by diabetes. These findings suggest that CSE/H₂S system can be integrated into pathogenesis of diabetic complications through modulation of pro-inflammatory and pro-fibrogenic mediator galectin-3.

Keywords: cystathionine-γ-lyase, diabetic heart, galectin-3, hydrogen sulfide, metformin, sodium hydrosulfide

Procedia PDF Downloads 227
685 The Scientific Phenomenon Revealed in the Holy Quran - an Update

Authors: Arjumand Warsy

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The Holy Quran was revealed to Prophet Mohammad (May Peace and Blessings of Allah be upon Him) over fourteen hundred years ago, at a time when majority of the people in Arabia were illiterate and very few could read or write. Any knowledge about medicine, anatomy, biology, astronomy, physics, geology, geophysics or other sciences were almost non-existent. Many superstitious and groundless believes were prevalent and these believes were passed down through past generations. At that time, the Holy Quran was revealed and it presented several phenomenon that have been only currently unveiled, as scientists have worked endlessly to provide explanation for these physical and biological phenomenon applying scientific technologies. Many important discoveries were made during the 20th century and it is interesting to note that many of these discoveries were already present in the Holy Quran fourteen hundred years ago. The Scientific phenomenon, mentioned in the Holy Quran, cover many different fields in biological and physical sciences and have been the source of guidance for a number of scientists. A perfect description of the creation of the universe, the orbits in space, the development process, development of hearing process prior to sight, importance of the skin in sensing pain, uniqueness of fingerprints, role of males in selection of the sex of the baby, are just a few of the many facts present in the Quran that have astonished many scientists. The Quran in Chapter 20, verse 50 states: قَالَ رَبُّنَا الَّذِيۤ اَعْطٰى كُلَّ شَيْءٍ خَلْقَهٗ ثُمَّ هَدٰى ۰۰ (He said "Our Lord is He, Who has given a distinctive form to everything and then guided it aright”). Explaining this brief statement in the light of the modern day Molecular Genetics unveils the entire genetic basis of life and how guidance is stored in the genetic material (DNA) present in the nucleus. This thread like structure, made of only six molecules (sugar, phosphate, adenine, thymine, cytosine and guanine), is so brilliantly structured by the Creator that it holds all the information about each and every living thing, whether it is viruses, bacteria, fungi, plants, animals or humans or any other living being. This paper will present an update on some of the physical and biological phenomena’ presented in the Holy Quran, unveiled using advanced technologies during the last century and will discuss how the need to incorporate this information in the curricula.

Keywords: The Holy Quran, scientific facts, curriculum, Muslims

Procedia PDF Downloads 357
684 Heritage and the Sustainable Development Goals: Successful Practices and Lessons Learnt from the Uk’s Global Challenges Research Fund and Newton Research Portfolios

Authors: Francesca Giliberto

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Heritage and culture, in general, plays a central role in addressing the complexity and broad variety of global development challenges, ranging from environmental degradation and refugee and humanitarian crisis to extreme poverty, food insecurity, persisting inequalities, and unsustainable urbanisation, just to mention some examples. Nevertheless, the potential of harnessing heritage to address global challenges has remained largely under-represented and underestimated in the most recent international development agenda adopted by the United Nations in 2015 (2030 Agenda). Among the 17 sustainable development goals (SDGs) and 169 associated targets established, only target 11.4 explicitly mentions heritage, stating that efforts should be strengthened “to protect and safeguard the world’s cultural and natural heritage in order to make our cities safe, resilient, and sustainable”. However, this global target continues to reflect a rather limited approach to heritage for development. This paper will provide a critical reflection on the contribution that using (tangible and intangible) heritage in international research can make to tackling global challenges and supporting the achievement of all the SDGs. It will present key findings and insights from the heritage strand of PRAXIS, a research project from the University of Leeds, which focuses on Arts and Humanities research across 300+ projects funded through the Global Challenges Research Fund and Newton Fund. In particular, this paper will shed light on successful practices and lessons learned from 87 research projects funded through the Global Challenges Research Fund and Newton Fund portfolios in 49 countries eligible for Official Development Assistance (ODA) between 2014 and 2021. Research data were collected through a desk assessment of project data available on UKRI Gateway to Research, online surveys, and qualitative interviews with research principal investigators and partners. The findings of this research provide evidence of how heritage and heritage research can foster innovative, interdisciplinary, inclusive, and transformative sustainable development and the achievement of the SDGs in ODA countries and beyond. This paper also highlights current challenges and research gaps that still need to be overcome to rethink current approaches and transform our development models to be more integrated, human-centred, and sustainable.

Keywords: global challenges, heritage, international research, sustainable development

Procedia PDF Downloads 74
683 Factors Influencing the Roles and Responsibilities of Middle Leaders in Saudi and English Primary Schools: A Comparative Critical Study

Authors: Saeed Musaid H. Alzahrani

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The role of middle leaders, especially in primary schools, is a multi-faced role that has been subject to changes in nature over recent decades, with claims for more distributed leadership practices. This research examines the way 18 middle leaders in Saudi and English primary schools conceptualise their roles and responsibilities, and different factors influencing those roles and responsibilities. It begins from the premise that both the power of the role and the values of middle leaders are grounded in cultural and political bases, a belief held by the researcher as an 'insider' within the Saudi educational leadership context. The study consisted of a comparative analysis of the role and the responsibilities of middle leaders in Saudi primary schools and their equivalents in English primary schools. A purely qualitative methodological stance was adopted, using in-depth face-to-face semi-structured interviews, observations and document analysis. Middle leaders were asked to reflect deeply on their perceptions and understanding of their roles and explain what they thought influenced their daily practices and responsibilities. The findings suggest that the concept of middle leadership has been influenced by power imposed from above by political authority, via internal and external hierarchical structures, which shapes the nature of the role of the middle leaders and forces them to comply. Middle leaders seem to believe they have the power to make decisions and promote change, but these findings suggest that this is illusory. The power that keeps middle leaders performing is the power of their cultural and religious values. Those values are the resource to which they turn in their search for more energy when they lack support and are short of time taken. Middle leaders in Saudi, just like their equivalents in English schools must comply with the requirements of their role. However, Saudi middle leaders are given no leeway to make decisions or implement change, neither do they have the culture of collegiality that seems to give middle leaders in England more power over their resources and decisions. However, in neither educational setting have middle leaders been given the power to lead, so they remain managers rather than leaders. The findings of this research suggest that there are more similarities between the educational settings of Saudi and England than differences; and in the light of different factors identified in the study, suggest the establishment of a framework for middle leadership, in the hope of enhancing the way the role is practiced.

Keywords: middle leader, primary school, power, educational leadership, value, culture, model, Saudi Arabia, England

Procedia PDF Downloads 192
682 The Implementation of Inclusive Education in Collaboration between Teachers of Special Education Classes and Regular Classes in a Preschool

Authors: Chiou-Shiue Ko

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As is explicitly stipulated in Article 7 of the Enforcement Rules of the Special Education Act as amended in 1998, "in principle, children with disabilities should be integrated with normal children for preschool education". Since then, all cities and counties have been committed to promoting preschool inclusive education. The Education Department, New Taipei City Government, has been actively recruiting advisory groups of professors to assist in the implementation of inclusive education in preschools since 2001. Since 2011, the author of this study has been guiding Preschool Rainbow to implement inclusive education. Through field observations, meetings, and teaching demonstration seminars, this study explored the process of how inclusive education has been successfully implemented in collaboration with teachers of special education classes and regular classes in Preschool Rainbow. The implementation phases for inclusive education in a single academic year include the following: 1) Preparatory stage. Prior to implementation, teachers in special education and regular classes discuss ways of conducting inclusive education and organize reading clubs to read books related to curriculum modifications that integrate the eight education strategies, early treatment and education, and early childhood education programs to enhance their capacity to implement and compose teaching plans for inclusive education. In addition to the general objectives of inclusive education, the objective of inclusive education for special children is also embedded into the Individualized Education Program (IEP). 2) Implementation stage. Initially, a promotional program for special education is implemented for the children to allow all the children in the preschool to understand their own special qualities and those of special children. After the implementation of three weeks of reverse inclusion, the children in the special education classes are put into groups and enter the regular classes twice a week to implement adjustments to their inclusion in the learning area and the curriculum. In 2013, further cooperation was carried out with adjacent hospitals to perform development screening activities for the early detection of children with developmental delays. 3) Review and reflection stage. After the implementation of inclusive education, all teachers in the preschool are divided into two groups to record their teaching plans and the lessons learned during implementation. The effectiveness of implementing the objective of inclusive education is also reviewed. With the collaboration of all teachers, in 2015, Preschool Rainbow won New Taipei City’s “Preschool Light” award as an exceptional model for inclusive education. Its model of implementing inclusive education can be used as a reference for other preschools.

Keywords: collaboration, inclusive education, preschool, teachers, special education classes, regular classes

Procedia PDF Downloads 430
681 Steps toward the Support Model of Decision-Making in Hungary: The Impact of the Article 12 of the UN Convention on the Rights of Persons with Disabilities on the Hungarian National Legislation

Authors: Szilvia Halmos

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Hungary was one of the first countries to sign and ratify the UN Convention on the Rights of Persons with Disabilities (hereinafter: CRPD). Consequently, Hungary assumed an obligation under international law to review the national law in the light of the Article 12 of the CRPD requiring the States parties to guarantee the equality of persons with disabilities in terms of legal capacity, and to replace the regimes of substitute decision-making by the instruments of supported decision-making. This article is often characterized as one of the key norms of the CRPD, since the legal autonomy of the persons with disabilities is an essential precondition of their participation in the social life on an equal basis with others, envisaged by the social paradigm of disability. This paper examines the impact of the CRPD on the relevant Hungarian national legal norms, with special focus on the relevant rules of the recently codified Civil Code. The employed research methodologies include (1) the specification of the implementation requirements imposed by the Article 12 of the CRPD, (2) the determination of the indicators of the appropriate implementation, (3) the critical analysis of compliance of the relevant Hungarian legal regulation with the indicators, (4) with respect to the relevant case law of the Hungarian Constitutional Court and ordinary courts, the European Court of Human Rights and the Committee of Rights of Persons with Disabilities and (5) to the available empirical figures on the functioning of substitute and supported decision-making regimes. It will be established that the new Civil Code has made large steps toward the equality of persons with disabilities in terms of legal capacity and the support model of decision-making by the introduction of some specific instruments of supported decision-making and the restriction of the application of guardianship. Nevertheless, the regulation currently in effect fails to represent some crucial principles of the Article 12 of the CRPD, such as the non-discrimination of persons with psycho-social disabilities, the support of the articulation of the will and preferences of the individual instead of his/her best interest in the course of decision-making. The changes in the practice of the substitute and the support model brought about by the new legal norms can also be assessed as significant, however, so far unsatisfactory. The number of registered supporters is rather low, and the preconditions of the effective functioning of the support (e.g. the proper training of the supporters) are not ensured.

Keywords: Article 12 of the UN CRPD, Hungarian law on legal capacity, persons with intellectual and psycho-social disabilities, supported decision-making

Procedia PDF Downloads 289
680 Development of PCL/Chitosan Core-Shell Electrospun Structures

Authors: Hilal T. Sasmazel, Seda Surucu

Abstract:

Skin tissue engineering is a promising field for the treatment of skin defects using scaffolds. This approach involves the use of living cells and biomaterials to restore, maintain, or regenerate tissues and organs in the body by providing; (i) larger surface area for cell attachment, (ii) proper porosity for cell colonization and cell to cell interaction, and (iii) 3-dimensionality at macroscopic scale. Recent studies on this area mainly focus on fabrication of scaffolds that can closely mimic the natural extracellular matrix (ECM) for creation of tissue specific niche-like environment at the subcellular scale. Scaffolds designed as ECM-like architectures incorporating into the host with minimal scarring/pain and facilitate angiogenesis. This study is related to combining of synthetic PCL and natural chitosan polymers to form 3D PCL/Chitosan core-shell structures for skin tissue engineering applications. Amongst the polymers used in tissue engineering, natural polymer chitosan and synthetic polymer poly(ε-caprolactone) (PCL) are widely preferred in the literature. Chitosan has been among researchers for a very long time because of its superior biocompatibility and structural resemblance to the glycosaminoglycan of bone tissue. However, the low mechanical flexibility and limited biodegradability properties reveals the necessity of using this polymer in a composite structure. On the other hand, PCL is a versatile polymer due to its low melting point (60°C), ease of processability, degradability with non-enzymatic processes (hydrolysis) and good mechanical properties. Nevertheless, there are also several disadvantages of PCL such as its hydrophobic structure, limited bio-interaction and susceptibility to bacterial biodegradation. Therefore, it became crucial to use both of these polymers together as a hybrid material in order to overcome the disadvantages of both polymers and combine advantages of those. The scaffolds here were fabricated by using electrospinning technique and the characterizations of the samples were done by contact angle (CA) measurements, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-Ray Photoelectron spectroscopy (XPS). Additionally, gas permeability test, mechanical test, thickness measurement and PBS absorption and shrinkage tests were performed for all type of scaffolds (PCL, chitosan and PCL/chitosan core-shell). By using ImageJ launcher software program (USA) from SEM photographs the average inter-fiber diameter values were calculated as 0.717±0.198 µm for PCL, 0.660±0.070 µm for chitosan and 0.412±0.339 µm for PCL/chitosan core-shell structures. Additionally, the average inter-fiber pore size values exhibited decrease of 66.91% and 61.90% for the PCL and chitosan structures respectively, compare to PCL/chitosan core-shell structures. TEM images proved that homogenous and continuous bead free core-shell fibers were obtained. XPS analysis of the PCL/chitosan core-shell structures exhibited the characteristic peaks of PCL and chitosan polymers. Measured average gas permeability value of produced PCL/chitosan core-shell structure was determined 2315±3.4 g.m-2.day-1. In the future, cell-material interactions of those developed PCL/chitosan core-shell structures will be carried out with L929 ATCC CCL-1 mouse fibroblast cell line. Standard MTT assay and microscopic imaging methods will be used for the investigation of the cell attachment, proliferation and growth capacities of the developed materials.

Keywords: chitosan, coaxial electrospinning, core-shell, PCL, tissue scaffold

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679 Material Response Characterisation of a PolyJet 3D Printed Human Infant Skull

Authors: G. A. Khalid, R. Prabhu, W. Whittington, M. D. Jones

Abstract:

To establish a causal relationship of infant head injury consequences, this present study addresses the necessary challenges of cranial geometry and the physical response complexities of the paediatric head tissues. Herein, we describe a new approach to characterising and understanding infant head impact mechanics by developing printed head models, using high resolution clinical postmortem imaging, to provide the most complete anatomical representation currently available, and biological material response data-matched polypropylene polymers, to replicate the relative mechanical response properties of immature cranial bone, sutures and fontanelles. Additive manufacturing technology was applied to creating a physical polymeric model of a newborn infant skull, using PolyJet printed materials. Infant skull materials responses, were matched by a response characterisation study, utilising uniaxial tensile testing (1 mm min-1 loading rate), to determine: the stiffness, ultimate tensile strength and maximum strain of rigid and rubber additively manufactured acrylates. The results from the mechanical experiments confirm that the polymeric materials RGD835 Vero White Plus (White), representing the frontal and parietal bones; RGD8510- DM Rigid Light Grey25 (Grey), representing the occipital bone; and FLX9870-DM (Black) representing the suture and fontanelles, were found to show a close stiffness -correlation (E) at ambient temperatures. A 3D physical model of infant head was subsequently printed from the matched materials and subsequently validated against results obtained from a series of Post Mortem Human Surrogate (PMHS) tests. A close correlation was demonstrated between the model impact tests and the PMHS. This study, therefore, represents a key step towards applying printed physical models to understanding head injury biomechanics and is useful in the efforts to predict and mitigate head injury consequences in infants, whether accidental or by abuse.

Keywords: infant head trauma, infant skull, material response, post mortem human subjects, polyJet printing

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678 Synchrotron Based Techniques for the Characterization of Chemical Vapour Deposition Overgrowth Diamond Layers on High Pressure, High Temperature Substrates

Authors: T. N. Tran Thi, J. Morse, C. Detlefs, P. K. Cook, C. Yıldırım, A. C. Jakobsen, T. Zhou, J. Hartwig, V. Zurbig, D. Caliste, B. Fernandez, D. Eon, O. Loto, M. L. Hicks, A. Pakpour-Tabrizi, J. Baruchel

Abstract:

The ability to grow boron-doped diamond epilayers of high crystalline quality is a prerequisite for the fabrication of diamond power electronic devices, in particular high voltage diodes and metal-oxide-semiconductor (MOS) transistors. Boron and intrinsic diamond layers are homoepitaxially overgrown by microwave assisted chemical vapour deposition (MWCVD) on single crystal high pressure, high temperature (HPHT) grown bulk diamond substrates. Various epilayer thicknesses were grown, with dopant concentrations ranging from 1021 atom/cm³ at nanometer thickness in the case of 'delta doping', up 1016 atom/cm³ and 50µm thickness or high electric field drift regions. The crystalline quality of these overgrown layers as regards defects, strain, distortion… is critical for the device performance through its relation to the final electrical properties (Hall mobility, breakdown voltage...). In addition to the optimization of the epilayer growth conditions in the MWCVD reactor, other important questions related to the crystalline quality of the overgrown layer(s) are: 1) what is the dependence on the bulk quality and surface preparation methods of the HPHT diamond substrate? 2) how do defects already present in the substrate crystal propagate into the overgrown layer; 3) what types of new defects are created during overgrowth, what are their growth mechanisms, and how can these defects be avoided? 4) how can we relate in a quantitative manner parameters related to the measured crystalline quality of the boron doped layer to the electronic properties of final processed devices? We describe synchrotron-based techniques developed to address these questions. These techniques allow the visualization of local defects and crystal distortion which complements the data obtained by other well-established analysis methods such as AFM, SIMS, Hall conductivity…. We have used Grazing Incidence X-ray Diffraction (GIXRD) at the ID01 beamline of the ESRF to study lattice parameters and damage (strain, tilt and mosaic spread) both in diamond substrate near surface layers and in thick (10–50 µm) overgrown boron doped diamond epi-layers. Micro- and nano-section topography have been carried out at both the BM05 and ID06-ESRF) beamlines using rocking curve imaging techniques to study defects which have propagated from the substrate into the overgrown layer(s) and their influence on final electronic device performance. These studies were performed using various commercially sourced HPHT grown diamond substrates, with the MWCVD overgrowth carried out at the Fraunhofer IAF-Germany. The synchrotron results are in good agreement with low-temperature (5°K) cathodoluminescence spectroscopy carried out on the grown samples using an Inspect F5O FESEM fitted with an IHR spectrometer.

Keywords: synchrotron X-ray diffaction, crystalline quality, defects, diamond overgrowth, rocking curve imaging

Procedia PDF Downloads 261