Search results for: metabolic syndrome change

Authors: Majid Rashidi, Shahrbanoo Farkhondeh Biabnavi

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The hydrodynamic instability phenomenon in a journal bearing may occur by either a reduction in the load carried by journal bearing, by an increase in the journal speed, by change in the lubricant viscosity, or a combination of these factors. The previous research and development work done to overcome the instability issue of journal bearings, operating in hydrodynamic lubricate regime, can be categorized as follows: A) Actively controlling the bearing sleeve by using piezo actuator, b) Inclusion of strategically located and shaped internal grooves within inner surface of the bearing sleeve, c) Actively controlling the bearing sleeve using an electromagnetic actuator, d)Actively and externally pressurizing the lubricant within a journal bearing set, and e)Incorporating tilting pads within the inner surface of the bearing sleeve that assume different equilibrium angular position in response to changes in the bearing design parameter such as speed and load. This work presents an innovative design concept for a 'smart journal bearing' set to operate in a stable hydrodynamic lubrication regime, despite variations in bearing speed, load, and its lubricant viscosity. The proposed bearing design allows adjusting its radial clearance for an attempt to maintain a stable bearing operation under those conditions that may cause instability for a bearing with a fixed radial clearance. The design concept allows adjusting the radial clearance at small increments in the order of 0.00254 mm. This is achieved by axially moving two symmetric conical rigid cavities that are in close contact with the conically shaped outer shell of a sleeve bearing. The proposed work includes a 3D model of the bearing that depicts the structural interactions of the bearing components. The 3D model is employed to conduct finite element Analyses to simulate the mechanical behavior of the bearing from a structural point of view. The concept of controlling of the radial clearance, as presented in this work, is original and has not been proposed and discuss in previous research. A typical journal bearing was analyzed under a set of design parameters, namely r =1.27 cm (journal radius), c = 0.0254 mm (radial clearance), L=1.27 cm (bearing length), w = 445N (bearing load), μ = 0.028 Pascale (lubricant viscosity). A shaft speed as 3600 r.p.m was considered, and the mass supported by the bearing, m, is set to be 4.38kg. The Summerfield Number associated with the above bearing design parameters turn to be, S=0.3. These combinations resulted in stable bearing operation. Subsequently, the speed was postulated to increase from 3600 r.p.mto 7200 r.p.m; the bearing was found to be unstable under the new increased speed. In order to regain stability, the radial clearance was increased from c = 0.0254 mm to0.0358mm. The change in the radial clearance was shown to bring the bearing back to stable an operating condition.

Keywords: adjustable clearance, bearing, hydrodynamic, instability, journal

Procedia PDF Downloads 279

Authors: Deniz Yurtoğlu

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Aerosols directly affect the radiative balance of the earth by absorbing and/or scattering the sun rays reaching the atmosphere and indirectly affect the balance by acting as a nucleus in cloud formation. The composition, physical, and chemical properties of aerosols vary depending on their sources and the time spent in the atmosphere. The Eastern Mediterranean Basin has a high aerosol load that is formed from different sources; such as anthropogenic activities, desert dust outbreaks, and the spray of sea salt; and the area is subjected to atmospheric transport from other locations on the earth. This region, which includes the deserts of Africa, the Middle East, and the Mediterranean sea, is one of the most affected areas by climate change due to its location and the chemistry of the atmosphere. This study aims to investigate the spatiotemporal deviation of aerosol load in the Eastern Mediterranean Basin between the years 2018-2022 with the help of a new pioneer satellite of ESA (European Space Agency), Sentinel-5P. The TROPOMI (The TROPOspheric Monitoring Instrument) traveling on this low-Earth orbiting satellite is a UV (Ultraviolet)-sensing spectrometer with a resolution of 5.5 km x 3.5 km, which can make measurements even in a cloud-covered atmosphere. By using Absorbing Aerosol Index data produced by this spectrometer and special scripts written in Python language that transforms this data into images, it was seen that the majority of the aerosol load in the Eastern Mediterranean Basin is sourced from desert dust and anthropogenic activities. After retrieving the daily data, which was separated from the NaN values, seasonal analyses match with the normal aerosol variations expected, which are high in warm seasons and lower in cold seasons. Monthly analyses showed that in four years, there was an increase in the amount of Absorbing Aerosol Index in spring and winter by 92.27% (2019-2021) and 39.81% (2019-2022), respectively. On the other hand, in the summer and autumn seasons, a decrease has been observed by 20.99% (2018-2021) and 0.94% (2018-2021), respectively. The overall variation of the mean absorbing aerosol index from TROPOMI between April 2018 to April 2022 reflects a decrease of 115.87% by annual mean from 0.228 to -0.036. However, when the data is analyzed by the annual mean values of the years which have the data from January to December, meaning from 2019 to 2021, there was an increase of 57.82% increase (0.108-0.171). This result can be interpreted as the effect of climate change on the aerosol load and also, more specifically, the effect of forest fires that happened in the summer months of 2021.

Keywords: aerosols, eastern mediterranean basin, sentinel-5p, tropomi, aerosol index, remote sensing

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Authors: I. M. Salama, R. N. Miftahof

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A functional element of the myenteric nervous plexus is a morphologically distinct ganglion. Composed of sensory, inter- and motor neurons and arranged via synapses in neuronal circuits, their task is to decipher and integrate spike coded information within the plexus into regulatory output signals. The stability of signal processing in response to a wide range of internal/external perturbations depends on the plasticity of individual neurons. Any aberrations in this inherent property may lead to instability with the development of a dynamics chaos and can be manifested as pathological conditions, such as intestinal dysrhythmia, irritable bowel syndrome. The aim of this study is to investigate patterns of signal transduction within a two-neuronal chain - a ganglion - under normal physiological and structurally altered states. The ganglion contains the primary sensory (AH-type) and motor (S-type) neurons linked through a cholinergic dendro somatic synapse. The neurons have distinguished electrophysiological characteristics including levels of the resting and threshold membrane potentials and spiking activity. These are results of ionic channel dynamics namely: Na+, K+, Ca++- activated K+, Ca++ and Cl-. Mechanical stretches of various intensities and frequencies are applied at the receptive field of the AH-neuron generate a cascade of electrochemical events along the chain. At low frequencies, ν < 0.3 Hz, neurons demonstrate strong connectivity and coherent firing. The AH-neuron shows phasic bursting with spike frequency adaptation while the S-neuron responds with tonic bursts. At high frequency, ν > 0.5 Hz, the pattern of electrical activity changes to rebound and mixed mode bursting, respectively, indicating ganglionic loss of plasticity and adaptability. A simultaneous increase in neuronal conductivity for Na+, K+ and Ca++ ions results in tonic mixed spiking of the sensory neuron and class 2 excitability of the motor neuron. Although the signal transduction along the chain remains stable the synchrony in firing pattern is not maintained and the number of discharges of the S-type neuron is significantly reduced. A concomitant increase in Ca++- activated K+ and a decrease in K+ in conductivities re-establishes weak connectivity between the two neurons and converts their firing pattern to a bistable mode. It is thus demonstrated that neuronal plasticity and adaptability have a stabilizing effect on the dynamics of signal processing in the ganglion. Functional modulations of neuronal ion channel permeability, achieved in vivo and in vitro pharmacologically, can improve connectivity between neurons. These findings are consistent with experimental electrophysiological recordings from myenteric ganglia in intestinal dysrhythmia and suggest possible pathophysiological mechanisms.

Keywords: neuronal chain, signal transduction, plasticity, stability

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Authors: Kehinde Emmanuel Atanlusi

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It is impossible to stifle the gust of social change as it makes its way through institutionalised hierarchies on its way to expressing itself. This advancement might also have repercussions for institutions, families, and politics, so modifying the norms and establishing new societal ideals. In the following paragraphs, it will explore how gender roles in the family have changed over time, how this has affected consumption, and how marketing has been influenced by these changes. It was decided to use the empirical research method, which led to several discoveries, one of which was that marketing in the pre-modern era was predicated on metanarratives and gender stereotypes. However, these aspects of marketing have undergone significant transformations in the post-modern era, which led to the formation of an assumption regarding what future marketing trends will be like. In spite of the fact that post-modern marketing methods have a number of drawbacks, it was suggested that these strategies be embraced and updated in the future in order to expand consumer bases and target audiences.

Keywords: Marketing, Gender Roles, Advertising, Decentralisation, Fragmentation

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Authors: Masato Sasaki, Masayoshi Yamamoto

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The majority of wireless power transfer (WPT) systems transfer power in a directional manner. This paper describes a discrete exciting voltage control technique for WPT via magnetic resonant coupling with two orthogonal transmitter coils (2D omni-directional WPT system) which can maximize the power transfer efficiency in response to the change of coupling status. The theory allows the equations of the efficiency of the system to be determined at all the rate of the mutual inductance. The calculated results are included to confirm the advantage to one directional WPT system and the validity of the theory and the equations.

Keywords: wireless power transfer, omni-directional, orthogonal, efficiency

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Authors: Chusit Apirumanekul, Chayanis Krittasudthacheewa, Ratchapat Ratanavaraha, Yanyong Inmuong

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Rapid economic development in the Lower Mekong region is leading to changes in water quantity and quality. Changes in land- and forest-use, infrastructure development, increasing urbanization, migration patterns and climate risks are increasing demands for water, within various sectors, placing pressure on scarce water resources. Appropriate policies, strategies, and planning are urgently needed for improved water resource management. Over the last decade, Thailand has experienced more frequent and intense drought situations, affecting the level of water storage in reservoirs along with insufficient water allocation for agriculture during the dry season. The Huay Saibat River Basin, one of the well-known water-scarce areas in the northeastern region of Thailand, is experiencing ongoing water scarcity that affects both farming livelihoods and household consumption. Drought management in Thailand mainly focuses on emergency responses, rather than advance preparation and mitigation for long-term solutions. Despite many efforts from local authorities to mitigate the drought situation, there is yet no long-term comprehensive water management strategy, that integrates climate risks alongside other uncertainties. This paper assesses the application in the Huay Saibat River Basin, of the Robust Decision Support framework, to explore the feasibility of multiple drought management policies; including a shift in cropping season, in crop changes, in infrastructural operations and in the use of groundwater, under a wide range of uncertainties, including climate and land-use change. A series of consultative meetings were organized with relevant agencies and experts at the local level, to understand and explore plausible water resources strategies and identify thresholds to evaluate the performance of those strategies. Three different climate conditions were identified (dry, normal and wet). Other non-climatic factors influencing water allocation were further identified, including changes from sugarcane to rubber, delaying rice planting, increasing natural retention storage and using groundwater to supply demands for household consumption and small-scale gardening. Water allocation and water use in various sectors, such as in agriculture, domestic, industry and the environment, were estimated by utilising the Water Evaluation And Planning (WEAP) system, under various scenarios developed from the combination of climatic and non-climatic factors mentioned earlier. Water coverage (i.e. percentage of water demand being successfully supplied) was defined as a threshold for water resource strategy assessment. Thresholds for different sectors (agriculture, domestic, industry, and environment) were specified during multi-stakeholder engagements. Plausible water strategies (e.g. increasing natural retention storage, change of crop type and use of groundwater as an alternative source) were evaluated based on specified thresholds in 4 sectors (agriculture, domestic, industry, and environment) under 3 climate conditions. 'Business as usual' was evaluated for comparison. The strategies considered robust, emerge when performance is assessed as successful, under a wide range of uncertainties across the river basin. Without adopting any strategy, the water scarcity situation is likely to escalate in the future. Among the strategies identified, the use of groundwater as an alternative source was considered a potential option in combating water scarcity for the basin. Further studies are needed to explore the feasibility for groundwater use as a potential sustainable source.

Keywords: climate change, robust decision support, scenarios, water resources management

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Authors: J. A. Marañón, L. Lozano C. De Los Santos, L. Martínez-Campesino, E. Caballero-Garrido, F. Galán-Estella

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Urinary incontinence (UI) is a significant health problem with considerable social and economic impact. An estimated 30% of women aged 30 to 60 years old have urinary incontinence (UI), while more than 50% of community-dwelling older women have the condition. Stress urinary incontinence and overactive bladder are the common types of incontinence The prevalence of stress and mixed (stress and urge) incontinence is higher than urge incontinence, but the latter is more likely to require treatment. In women, moderate and severe have a prevalence ranging from about 12% to 17% The objectives of this study was to examine the effect of the supplementation of tablets containing Dropsordry in women with urge urinary incontinence (UUI). Dropsordry is a novel active containing phytoestrogens from SOLGEN, the high genistin soy bean extract and pyrogallol plus polyphenols from standarized pumpkin seed extract,. The study was a single-center, not randomiized open prospective, study. 28 women with urinary incontinence ≥45 years were enrolled in this study (45-62 y. old age . Mean 52 y old). Items related to UI symptoms, were previously collected (T0) and these ítems were reviewed at the final of the study – 8 weeks. (T2). The presence of UI was previously diagnosed using the International Continence Society standards (ICS). Relationships between presence of UI and potential related factors as diabetes were also explored. Daily urinary test control was performed during the 8 weeks of treatment. Daily dosage was 1 g/ day (500 mg twice per day) from 0 to 4 week (T1), following a 500 mg/day daily intake from 4 to 8 week (T2). After eight weeks of treatment, the urgency grade score was reduced a 24,7%. The total urge episodes was reduced a 46%. Surprisingly there was no a significant change in daytime urinations (< 5%), however nocturia was reduced a 69,35%. Strenght Urinary Incontinence (SUI) was also tested showing a remarkably 52,17% reduction. Moreover the use of daily pantyliners was reduced a 66,25%. In addition, it was performed a panel test survey with quests when subjects of the study were enrolled (T0) and the same quests was performed after 8 weeks of supplementation (T2). 100% of the enrolled women fullfilled the ICIQ-SF quest (Spanish versión) and they were also questioned about the effects they noticed in response to taking the supplement and the change in quality of life. Interestingly no side effects were reported. There was a 96,2% of subjective satisfaction and a 85,8% objective score in the improvement of quality of life. CONCLUSION: the combination of High genistin isoflavones and pumpkin seed pyrogallol in Dropsordry tablets seems to be a safe and highly effective supplementation for the relieve of the urinary incontinence symptoms and a better quality of life in perimenopause women .

Keywords: isoflavones, pumpkin, menopause, incontinence, genistin

Procedia PDF Downloads 398

Authors: B. T. Naveen Kumar, Anuj Tyagi, Niraj Kumar Singh, Visanu Boonyawiwat, A. H. Shanthanagouda, Orawan Boodde, K. M. Shankar, Prakash Patil, Shubhkaramjeet Kaur

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Early mortality syndrome (EMS)/Acute Hepatopancreatic Necrosis Disease (AHPND) has emerged as a major obstacle for the shrimp farming around the world. It is caused by a strain of Vibrio parahaemolyticus. The possible preventive and control measure is, early and rapid detection of the pathogen in the broodstock, post-larvae and monitoring the shrimp during the culture period. Polymerase chain reaction (PCR) based early detection methods are good, but they are costly, time taking and requires a sophisticated laboratory. The present study was conducted to develop a simple, sensitive and rapid diagnostic farmer level kit for the reliable detection of AHPND in shrimp. A panel of monoclonal antibodies (MAbs) were raised against the recombinant Pir B protein (rPirB). First, an immunodot was developed by using MAbs G3B8 and Mab G3H2 which showed specific reactivity to purified r-PirB protein with no cross-reactivity to other shrimp bacterial pathogens (AHPND free Vibrio parahaemolyticus (Indian strains), V. anguillarum, WSSV, Aeromonas hydrophila, and Aphanomyces invadans). Immunodot developed using Mab G3B8 is more sensitive than that with the Mab G3H2. However, immunodot takes almost 2.5 hours to complete with several hands-on steps. Therefore, the flow-through assay (FTA) was developed by using a plastic cassette containing the nitrocellulose membrane with absorbing pads below. The sample was dotted in the test zone on the nitrocellulose membrane followed by continuos addition of five solutions in the order of i) blocking buffer (BSA) ii) primary antibody (MAb) iii) washing Solution iv) secondary antibody and v) chromogen substrate (TMB) clear purple dots against a white background were considered as positive reactions. The FTA developed using MAbG3B8 is more sensitive than that with MAb G3H2. In FTA the two MAbs showed specific reactivity to purified r-PirB protein and not to other shrimp bacterial pathogens. The FTA is simple to farmer/field level, sensitive and rapid requiring only 8-10 min for completion. Tests can be developed to kits, which will be ideal for use in biosecurity, for the first line of screening (at the port or pond site) and during monitoring and surveillance programmes overall for the good management practices to reduce the risk of the disease.

Keywords: acute hepatopancreatic necrosis disease, AHPND, flow-through assay, FTA, farmer level, immunodot, pond site, shrimp

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Authors: Zi-Gui Huang, Shen-Hsien Hu

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This study proposes a fabrication of phononic-crystal acoustic wave device. A graphene-like atomic structure was adopted as the main research subject, and a graphene-like structure was designed using piezoelectric material zinc oxide and its periodic boundary conditions were defined using the finite element method. The effects of a hexagonal honeycomb structure were investigated regarding the band gap phenomenon. The use of micro-electromechanical systems process technology to make the film etched micron graphics, designed to produce four kinds of different piezoelectric structure (plat, periodic, single defect and double defects). Frequency response signals and phase change were also measured in this paper.

Keywords: MEMS, phononic crystal, piezoelectric material, Zinc oxide

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Authors: P. Kavuma, J. Mukasa, M. Lusunku

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Background and Problem: The widespread poverty in Africa- together with the negative impacts of climate change-are two great global challenges that call for everyone’s involvement including Architects. This in particular places serious challenges on architects to have additional skills in both Entrepreneurship and Environmental Design (SEED). Regrettably, while Architectural Training in most African Universities including those from Uganda lack comprehensive implementation of SEED in their curricula, regulatory bodies have not contributed towards the effective integration of SEED in their professional practice. In response to these challenges, Nkumba University (NU) under Architect Kavuma Paul supported by the Uganda Chambers of Architects– initiated the SEED integration in the undergraduate Architectural curricula to cultivate SEED know-how and examples of best practices. Main activities: Initiated in 2007, going beyond the traditional Architectural degree curriculum, the NU Architect department offers SEED courses including provoking passions for creating desirable positive changes in communities. Learning outcomes are assessed theoretically and practically through field projects. The first set of SEED graduates came out in 2012. As part of the NU post-graduation and alumni survey, in October 2014, the pioneer SEED graduates were contacted through automated reminder emails followed by individual, repeated personal follow-ups via email and phone. Out of the 36 graduates who responded to the survey, 24 have formed four (4) private consortium agencies of 5-7 graduates all of whom have pioneered Ugandan-own-cultivated Architectural social projects that include: fishing farming in shipping containers; solar powered mobile homes in shipping containers, solar powered retail kiosks in rural and fishing communities, and floating homes in the flood-prone areas. Primary outcomes: include being business self –reliant in creating the social change the architects desired in the communities. Examples of the SEED project returns to communities reported by the graduates include; employment creation via fabrication, retail business, marketing, improved diets, safety of life and property, decent shelter in the remote mining and oil exploration areas. Negative outcomes-though not yet evaluated include the disposal of used-up materials. Conclusion: The integration of SEED in Architectural Training has established a baseline benchmark and a replicable model based on best practice projects.

Keywords: architectural training, entrepreneurship, environment, integration

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Authors: Ibraheem A. K. Mahameed

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The aim of this study is to identify the risks affecting time performance of building construction projects in the West Bank in Palestine from contractors’ viewpoint. 38 risks that might affect time performance of building construction projects were defined through a detailed literature review. These risks have been classified into 6 groups: project, managerial, consultant, financial, external, and construction items. A questionnaire survey was performed to rank the considered risks in terms of severity and frequency. The analysis of the survey indicated that the top five risks affecting time performance of building construction projects in Palestine are: award project to the lowest price, political situation, poor communication and coordination between construction parties, change orders, and financial status of contractor.

Keywords: delay, time performance, construction, building

Procedia PDF Downloads 464

Authors: Patrícia Severino, Luciana Nalone, Daniele Martins, Marco Chaud, Classius Ferreira, Cristiane Bani, Ricardo Albuquerque

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Hydrogels produced with polymers have been used in the development of dressings for wound treatment and tissue revitalization. Our study on polymer nanocomposites containing silver nanoparticles shows antimicrobial activity and applications in wound healing. The effects are linked with the slow oxidation and Ag⁺ liberation to the biological environment. Furthermore, bacterial cell membrane penetration and metabolic disruption through cell cycle disarrangement also contribute to microbial cell death. The silver antimicrobial activity has been known for many years, and previous reports show that low silver concentrations are safe for human use. This work aims to develop a hydrogel using natural polymers (sodium alginate and gelatin) combined with silver nanoparticles for wound healing and with antimicrobial properties in cutaneous lesions. The hydrogel development utilized different sodium alginate and gelatin proportions (20:80, 50:50 and 80:20). The silver nanoparticles incorporation was evaluated at the concentrations of 1.0, 2.0 and 4.0 mM. The physico-chemical properties of the formulation were evaluated using ultraviolet-visible (UV-Vis) absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric (TG) analysis. The morphological characterization was made using transmission electron microscopy (TEM). Human fibroblast (L2929) viability assay was performed with a minimum inhibitory concentration (MIC) assessment as well as an in vivo cicatrizant test. The results suggested that sodium alginate and gelatin in the (80:20) proportion with 4 mM of AgNO₃ in the (UV-Vis) exhibited a better hydrogel formulation. The nanoparticle absorption spectra of this analysis showed a maximum band around 430 - 450 nm, which suggests a spheroidal form. The TG curve exhibited two weight loss events. DSC indicated one endothermic peak at 230-250 °C, due to sample fusion. The polymers acted as stabilizers of a nanoparticle, defining their size and shape. Human fibroblast viability assay L929 gave 105 % cell viability with a negative control, while gelatin presented 96% viability, alginate: gelatin (80:20) 96.66 %, and alginate 100.33 % viability. The sodium alginate:gelatin (80:20) exhibited significant antimicrobial activity, with minimal bacterial growth at a ratio of 1.06 mg.mL⁻¹ in Pseudomonas aeruginosa and 0.53 mg.mL⁻¹ in Staphylococcus aureus. The in vivo results showed a significant reduction in wound surface area. On the seventh day, the hydrogel-nanoparticle formulation reduced the total area of injury by 81.14 %, while control reached a 45.66 % reduction. The results suggest that silver-hydrogel nanoformulation exhibits potential for wound dressing therapeutics.

Keywords: nanocomposite, wound healing, hydrogel, silver nanoparticle

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Authors: V. Nikkhah Rashidabad, M. Manteghian, M. Masoumi, S. Mousavian

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In this research, the changes in bubbles diameter and number that may occur due to the change in heat flux of pure water during pool boiling process. For this purpose, test equipment was designed and developed to collect test data. The bubbles were graded using Caliper Screen software. To calculate the growth and nucleation rates of bubbles under different fluxes, population balance model was employed. The results show that the increase in heat flux from q=20 kw/m2 to q=102 kw/m2 raised the growth and nucleation rates of bubbles.

Keywords: heat flux, bubble growth, bubble nucleation, population balance model

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Authors: A. A. Azab

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In this work, Sm0.6Sr0.4CoxMn1-xO3 (x=0, 0.1, 0.2 and 0.3) was synthesized by sol-gel method for magnetocaloric effect (MCE) applications. XRD analysis confirmed formation of the required orthorhombic phase of perovskite, and there is crystallographic phase transition as a result of substitution. Maxwell-Wagner interfacial polarisation and Koops phenomenological theory were used to investigate and analyze the temperature and frequency dependency of the dielectric permittivity. The phase transition from the ferromagnetic to the paramagnetic state was demonstrated to be second order. Based on the isothermal magnetization curves obtained at various temperatures, the magnetic entropy change was calculated. A magnetocaloric effect (MCE) over a wide temperature range was studied by determining DSM and the relative cooling power (RCP).

Keywords: magnetocaloric effect, pperovskite, magnetic phase transition, dielectric permittivity

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Authors: Angela T. H. Kwan, Saman Arfaie, Joseph Therriault, Zahra Azizi, Firoza Z. Lussier, Cecile Tissot, Mira Chamoun, Gleb Bezgin, Stijn Servaes, Jenna Stevenon, Nesrine Rahmouni, Vanessa Pallen, Serge Gauthier, Pedro Rosa-Neto

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Alzheimer’s disease (AD) can be detected in living people using in vivo biomarkers of amyloid-β (Aβ) and tau, even in the absence of cognitive impairment during the preclinical phase. [¹⁸F]-MK-6420 is a high affinity positron emission tomography (PET) tracer that quantifies tau neurofibrillary tangles, but its ability to predict cognitive changes associated with early AD symptoms, such as memory decline, is unclear. Here, we assess the prognostic accuracy of baseline [18F]-MK-6420 tau PET for predicting longitudinal memory decline in asymptomatic elderly individuals. In a longitudinal observational study, we evaluated a cohort of cognitively normal elderly participants (n = 111) from the Translational Biomarkers in Aging and Dementia (TRIAD) study (data collected between October 2017 and July 2020, with a follow-up period of 12 months). All participants underwent tau PET with [¹⁸F]-MK-6420 and Aβ PET with [¹⁸F]-AZD-4694. The exclusion criteria included the presence of head trauma, stroke, or other neurological disorders. There were 111 eligible participants who were chosen based on the availability of Aβ PET, tau PET, magnetic resonance imaging (MRI), and APOEε4 genotyping. Among these participants, the mean (SD) age was 70.1 (8.6) years; 20 (18%) were tau PET positive, and 71 of 111 (63.9%) were women. A significant association between baseline Braak I-II [¹⁸F]-MK-6240 SUVR positivity and change in composite memory score was observed at the 12-month follow-up, after correcting for age, sex, and years of education (Logical Memory and RAVLT, standardized beta = -0.52 (-0.82-0.21), p < 0.001, for dichotomized tau PET and -1.22 (-1.84-(-0.61)), p < 0.0001, for continuous tau PET). Moderate cognitive decline was observed for A+T+ over the follow-up period, whereas no significant change was observed for A-T+, A+T-, and A-T-, though it should be noted that the A-T+ group was small.Our results indicate that baseline tau neurofibrillary tangle pathology is associated with longitudinal changes in memory function, supporting the use of [¹⁸F]-MK-6420 PET to predict the likelihood of asymptomatic elderly individuals experiencing future memory decline. Overall, [¹⁸F]-MK-6420 PET is a promising tool for predicting memory decline in older adults without cognitive impairment at baseline. This is of critical relevance as the field is shifting towards a biological model of AD defined by the aggregation of pathologic tau. Therefore, early detection of tau pathology using [¹⁸F]-MK-6420 PET provides us with the hope that living patients with AD may be diagnosed during the preclinical phase before it is too late.

Keywords: alzheimer’s disease, braak I-II, in vivo biomarkers, memory, PET, tau

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Authors: M. Tiachachat, M. Mihoubi

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The Bell polynomials are special polynomials in combinatorial analysis that have a wide range of applications in mathematics. They have interested many authors. The exponential partial Bell polynomials have been well reduced to some special combinatorial sequences. Numerous researchers had already been interested in the above polynomials, as evidenced by many articles in the literature. Inspired by this work, in this work, we propose a family of special polynomials named after the 2-successive partial Bell polynomials. Using the combinatorial approach, we prove the properties of these numbers, derive several identities, and discuss some special cases. This family includes well-known numbers and polynomials such as Stirling numbers, Bell numbers and polynomials, and so on. We investigate their properties by employing generating functions

Keywords: 2-associated r-Stirling numbers, the exponential partial Bell polynomials, generating function, combinatorial interpretation

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Authors: Andreas Walmsley, Shobana Partington, Rebecca Armstrong, Harold Goodwin

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In the UK, more than 1 in 5 workers earn less than a living wage. The hospitality sector is particularly affected where it has been claimed two thirds of workers earn less than the living wage. The UK Government is set to introduce (April 2016) a national living wage (NLW) which is therefore likely to have a significant impact on the hospitality sector. To date limited data exists that focus on how hotels are tackling the issue, what stakeholder perceptions are towards the change in legislation, and how the NLW may affect working patterns in the sector. This study draws on interviews with a range of key stakeholders such as hotel HR and general managers as well as industry representatives to explore these issues within the broader context of responsible tourism. Data collection is still ongoing and is scheduled to be completed by the end of June 2016.

Keywords: hospitality, living wage, responsible tourism, tourism employment

Procedia PDF Downloads 379

Authors: Nursyafiq Ali Shibramulisi, Nor Farah Fauzi, Nur Azniza Zawin Anuar, Nurul Atikah Azmi, Janice Hew Pei Fang

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Background: Work related musculoskeletal disorders (WRMD) among dental personnel have been underestimated and under-reported worldwide and specifically in Malaysia. The problem will arise and progress slowly over time, as it results from accumulated injury throughout the period of work. Several risk factors, such as repetitive movement, static posture, vibration, and adapting poor working postures, have been identified to be contributing to WRMSD in dental practices. Dental personnel is at higher risk of getting this problem as it is their working nature and core business. This would cause pain and dysfunction syndrome among them and result in absence from work and substandard services to their patients. Methodology: A cross-sectional study involving 19 government dental clinics in Perak was done over the period of 3 months. Those who met the criteria were selected to participate in this study. Malay version of the Self-Reported Nordic Musculoskeletal Discomfort Form was used to identify the prevalence of WRMSD, while the intensity of pain in the respective regions was evaluated using a 10-point scale according to ‘Pain as The 5ᵗʰ Vital Sign’ by MOH Malaysia and later on were analyzed using SPSS version 25. Descriptive statistics, including mean and SD and median and IQR, were used for numerical data. Categorical data were described by percentage. Pearson’s Chi-Square Test and Spearman’s Correlation were used to find the association between the prevalence of WRMSD and other socio-demographic data. Results: 159 dentists, 73 dental therapists, 26 dental lab technicians, 81 dental surgery assistants, and 23 dental attendants participated in this study. The mean age for the participants was 34.9±7.4 and their mean years of service was 9.97±7.5. Most of them were female (78.5%), Malay (71.3%), married (69.6%) and right-handed (90.1%). The highest prevalence of WRMSD was neck (58.0%), followed by shoulder (48.1%), upper back (42.0%), lower back (40.6%), hand/wrist (31.5%), feet (21.3%), knee (12.2%), thigh 7.7%) and lastly elbow (6.9%). Most of those who reported having neck pain scaled their pain experiences at 2 out of 10 (19.5%), while for those who suffered upper back discomfort, most of them scaled their pain experience at 6 out of 10 (17.8%). It was found that there was a significant relationship between age and pain at neck (p=0.007), elbow (p=0.027), lower back (p=0.032), thigh (p=0.039), knee (p=0.001) and feet (p=0.000) regions. Job position also had been found to be having a significant relationship with pain experienced at the lower back (p=0.018), thigh (p=0.011), knee, and feet (p=0.000). Conclusion: The prevalence of WRMSD among dental personnel in Perak was found to be high. Age and job position were found to be having a significant relationship with pain experienced in several regions. Intervention programs should be planned and conducted to prevent and reduce the occurrence of WRMSD, as all harmful or unergonomic practices should be avoided at all costs.

Keywords: WRMSD, ergonomic, dentistry, dental

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Authors: Jasmeet Kaur, Anup Singh, Shashikant Iyengar, Arun Kumar, Ira Sahay

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Latent autoimmune diabetes in adults (LADA) is an irreversible autoimmune disease that affects insulin production. LADA is characterized by the production of Glutamic acid decarboxylase (GAD) antibodies, which is similar to type 1 diabetes. Individuals with LADA may eventually develop overt diabetes and require insulin. In this condition, the pancreas produces little or no insulin, which is a hormone used by the body to allow glucose to enter cells and produce energy. While type 1 diabetes was traditionally associated with children and teenagers, its prevalence has increased in adults as well. LADA is frequently misdiagnosed as type 2 diabetes, especially in adulthood when type 2 diabetes is more common. LADA develops in adulthood, usually after age 30. Managing LADA involves metabolic control with exogenous insulin and prolonging the life of surviving beta cells, thereby slowing the disease's progression. This case study examines the impact of approximately 3 months of low-carbohydrate dietary intervention in a 42-year-old woman with LADA who was initially misdiagnosed as having type 2 diabetes. Her c-peptide was 0.13 and her HbA1c was 9.3% when this trial began. Low-carbohydrate interventions have been shown to improve blood sugar levels, including fasting, post-meal, and random blood sugar levels, as well as haemoglobin levels, blood pressure, energy levels, sleep quality, and satiety levels. The use of low-carbohydrate dietary intervention significantly reduces both hypo- and hyperglycaemia events. During the 3 months of the study, there were 2 to 3 hyperglycaemic events owing to physical stress and a single hypoglycaemic event. Low-carbohydrate dietary therapies lessen insulin dose inaccuracy, which explains why there were fewer hyperglycaemic and hypoglycaemic events. In three months, the glycated haemoglobin (HbA1c) level was reduced from 9.3% to 6.3%. These improvements occur without the need for caloric restriction or physical activity. Stress management was crucial aspect of the treatment plan as stress-induced neuroendocrine hormones can cause immunological dysregulation. Additionally, supplements that support immune system and reduce inflammation were used as part of the treatment during the trial. Long-term studies are needed to track disease development and corroborate the claim that such dietary treatments can prolong the honeymoon phase in LADA. Various factors can contribute to additional autoimmune attacks, so measuring c-peptide is crucial on a regular basis to determine whether insulin levels need to be adjusted.

Keywords: autoimmune, diabetes, LADA, low_carb, nutrition

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Authors: Elizabeth Latham

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Aristotle’s definition of substance from Metaphysics is relevant to the Catholic transubstantiation of the Eucharist, the idea that the actual substance of bread and wine is replaced by the substance of the body and blood of Christ. Assuming the physiological nature of the subjects do not change, the Aristotelian view on the nature of substance seems to be incompatible with this belief, since bread and wine have essential qualities different from those of flesh and blood. However, based on a theological view of the essence of the body and blood of Christ as salvation along with the essence of Eucharist, transubstantiation can fit within Aristotle’s brackets. This is one step further than theologians like Aquinas have gone in their similar discussions. Using his work as a method by which to understand the apparently impossible act of transforming food to flesh provides a logical angle on a question of faith.

Keywords: aristotle, catholicism, eucharist, metaphysics transubstantiation

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Authors: Y. C. Ching, K. H. Chong

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The increasing of environmental awareness has led to grow interest in the expansion of materials with eco-friendly attributes. In this study, a 3 ply sandwich layer of kenaf fiber reinforced unsaturated polyester with various fiber orientations was developed. The effect of the fiber orientation on mechanical and thermal stability properties of polyester was studied. Unsaturated polyester as a face sheets and kenaf fibers as a core was fabricated with combination of hand lay-up process and cold compression method. Tested result parameters like tensile, flexural, impact strength, melting point, and crystallization point were compared and recorded based on different fiber orientation. The failure mechanism and property changes associated with directional change of fiber to polyester composite were discussed.

Keywords: kenaf fiber, polyester, tensile, thermal stability

Procedia PDF Downloads 355

Authors: M. H. A. D. de Silva, R. P. Hewawasam, M. A. G. Iresha

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Macrosomia is common in infants born to not only women diagnosed with gestational diabetes mellitus but also non-diabetic obese women. Maternal Body Mass Index (BMI) correlates with the incidence of large for gestational age infants. Obesity has reached epidemic levels in modern societies. During the past two decades, obesity in children and adolescents has risen significantly in Asian populations including Sri Lanka. There is increasing evidence to believe that infants who are born large for gestational age are more likely to be obese in childhood and adolescence and are at risk of cardiovascular and metabolic complications later in life. It is also established that Asians have lower skeletal muscle mass, low bone mineral content and excess body fat for a given BMI indicating a genetic predisposition in the occurrence of obesity. The objective of this study is to determine the effect of maternal weight, weight gain during pregnancy, c-peptide and insulin concentrations in the cord blood on the birth of appropriate for and large for gestational age infants in a tertiary care center in Southern Sri Lanka. Umbilical cord blood was collected from 90 newborns (Male 40, Female 50; gestational age 35-42 weeks) after double clamping the umbilical cord before separation of the placenta and the concentration of insulin and C-peptide were measured by ELISA technique. Anthropometric parameters of the newborn such as birth weight, length, ponderal index, occipital frontal, chest, hip and calf circumferences were measured, and characteristics of the mother were collected. The relationship between insulin, C-peptide and anthropometrics were assessed by Spearman correlation. The multiple logistic regression analysis examined influences of maternal weight, weight gain during pregnancy, C-peptide and insulin concentrations in cord blood as covariates on the birth of large for gestational age infants. A significant difference (P<0.001) was observed between the insulin levels of infants born large for gestational age (18.73 ± 0.52 µlU/ml) and appropriate for gestational age (13.08 ± 0.56 µlU/ml). Consistently, A significant decrease in concentration (41.68%, P<0.001) was observed between C-peptide levels of infants born large for gestational age and appropriate for gestational age. Cord blood insulin and C-peptide levels had a significant correlation with birth weight (r=0.35, P<0.05) of the newborn at delivery. Maternal weight and BMI which are indicators of maternal nutrition were proven to be directly correlated with birth weight and length. To our knowledge, this relationship was investigated for the first time in a Sri Lankan setting and was also evident in our results. This study confirmed the fact that insulin and C-peptide play a major role in regulating fetal growth. According to the results obtained in this study, we can suggest that the increased BMI of the mother has a direct influence on increased maternal insulin secretion, which may subsequently affect cord insulin and C-peptide levels and also birth weight of the infant.

Keywords: C-peptide, insulin, large for gestational age, maternal weight

Procedia PDF Downloads 162

Authors: Jacob Dangerfield, Jacob Pollard, Jennifer DeCou

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Introduction: Burnout, anxiety, and depression are three conditions that are prevalent in medical providers. This is especially the case in the field of anesthesia, which has a high number of providers suffering from burnout and burnout syndrome. A major contributor to this issue is isolation in the workplace, with a perceived lack of peer support as a major risk factor for burnout. Two organizational interventions that can be done to help improve this issue are small group sessions and providing affordable mental health services. Per American College of Graduate Medical Education (ACGME) Guidelines, these affordable mental health services are a requirement of all residency programs, but for a variety of reasons, many residents do not access them. As physicians, we are often not good at asking for help. With this in mind, we hypothesized that carrying out small group resiliency sessions facilitated by Graduate Medical Education (GME) Wellness Counselors would improve both resident peer support as well as the likelihood that a resident will reach out to GME Wellness in a time of need. Methods: We held small group resiliency sessions with the GME Wellness Mental Health Professionals during protected didactic time. These sessions were small groups, including the members of one’s class (i.e., first-year residents on their own), and were facilitated by 1-2 mental health professionals. After these sessions, we surveyed residents who attended using a short Google Forms survey and using a 5-point Likert Scale, asked residents about some outcomes from the session. A “strongly agree” or “agree” was considered a positive response. Results: Results from our survey showed that the resident sessions had multiple positive outcomes. This survey was sent to 29 residents, and we had a 62% response rate. We found out through this survey that these small group sessions had a perceived positive impact on resident personal well-being, increased perceived peer support from classmates, and made residents more likely to reach out to GME Wellness in the future. Perceived positive impact on well-being was found in 83% of resident respondents, improved perceived peer support in 83% of respondents, and 78% of resident respondents stated that this session increased their likelihood of reaching out to mental health professionals. Conclusions: Through this study, we can conclude that our hypothesis was correct in that Small Group Resiliency Sessions that are facilitated by GME Wellness Counselors improve both resident peer support as well as the likelihood a resident reaches out to these mental health professionals in time of need. We believe these findings are very important as they address two important factors that can aid in decreasing a provider’s risk of experiencing burnout. Through this simple means, we believe other residency programs can help the well-being of their residents, and together, we can decrease the number of cases of burnout in anesthesia.

Keywords: anesthesiology, burnout, wellness, depression, residents, trainees, mental health

Procedia PDF Downloads 49

Authors: Rossana Mancini

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The charm of a ruin colonised by wild plants and flowers is part of Western culture. The relationship between ruins and vegetation involves a wide range of different fields of research. During the first phase of the research the most important writings and projects about this argument were investigated, to understand how the perception of the co-existence of ruins and vegetation has changed over time and to investigate the various different approaches that these different fields have adopted when tackling this issue. The paper presents some practical examples of projects carried out from the early 1900s on. The major result is that specifically regards conservation, the best attitude is the management of change, an inevitable process when it comes to the co-existence of ruins and nature and, particularly, ruins and vegetation. Limiting ourselves to adopting measures designed to stop, or rather slow down, the increasing level of entropy (and therefore disorder) may not be enough.

Keywords: ruins, vegetation, conservation, archaeology, architecture

Procedia PDF Downloads 324

Authors: Na Li, Samuel Simon Araya, Søren Knudsen Kær

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This study investigates the effects of operating parameters of different current density, temperature and pressure on the performance of a proton exchange membrane (PEM) water electrolysis stack. A 7-cell PEM water electrolysis stack was assembled and tested under different operation modules. The voltage change and polarization curves under different test conditions, namely current density, temperature and pressure, were recorded. Results show that higher temperature has positive effect on overall stack performance, where temperature of 80 ℃ improved the cell performance greatly. However, the cathode pressure and current density has little effect on stack performance.

Keywords: PEM electrolysis stack, current density, temperature, pressure

Procedia PDF Downloads 194

Authors: Surajo Ladan

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English has been in existence in Nigeria since colonial period. The advent of English in Nigeria has caused a lot of linguistic changes in Nigerian languages especially among the educated elites and to some extent, even the ordinary people were not spared from this phenomenon. This scenario has generated a linguistic situation which culminated into the creation of Nigerian Pidgin that are conglomeration of English and other Nigerian languages. English has infiltrated the Nigerian languages to a point that a typical Nigerian can hardly talk without code-switching or using one English word or the other. The existence of English loanwords in Nigerian languages has taken another dimension in this scientific and technological age. Most of scientific and technological inventions are products of English language which are virtually adopted into the languages with phonological, morphological, and sometimes semantic variations. This paper is of the view that there should be a re-think and agitation from Nigerians to protect their languages from the linguistic genocide of English which are invariably facing extinction.

Keywords: linguistic change, loanword, phenomenon, pidgin

Procedia PDF Downloads 853

Authors: Nada Abdelsadig Moahamed Saied

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Female Genital Mutilation (FGM) and other similar traditional cultural practices pose a significant problem for Sudanese society. Such actions are severe and seriously detrimental to people's health since they are based on false social perceptions. To address these problems, numerous institutions and organizations were compelled to act rapidly. Female circumcision, or FGM, is one of the riskiest practices. It is referred to as the excision of the genitalia. Any surgeries involving the total or partial removal of the external female genitalia for non-medical reasons fall under this category. The results of FGM can vary depending on the kind and degree of the operation. These can be categorized as short-term, mid-term, or long-term issues. Infections, including the Human, blood, discomfort, and difficulty urinating are the immediate effects. FGM is defined by the World Health Organization (WHO) as practices that purposefully damage or modify female genital organs for non-medical purposes. It often takes place between the ages of one and fifteen. The girl's right to decide on important choices affecting her sexual and reproductive health is violated because the act is usually performed without her consent and frequently against her will. UNICEF, the United Nations International Children's Emergency Fund, aggressively combats the issue of FGM in Sudan. Numerous programs were started by NGOs to stop the practice. To our knowledge, no scientific study has been conducted to evaluate the effects of such social marketing techniques on simulating and comprehending society’s feelings surrounding FGM. This study proposes the development of a structural equation model aiming to determine the impact of awareness programs on people’s intentions to adopt the behavior of abandoning FGM based on theoretical models of behavior change. The model incorporates all the relevant factors that contribute to FGM and possible strategic actions to tackle this problem. The theoretical backdrop for FGM is presented in the next section, which also explains the practice's history, justifications, and potential treatments. The methodology section that follows describes the structural equation model. The proposed model, which compiles all the pertinent elements into a single image, is presented in the fourth part. Finally, conclusions are reached, and suggestions for further research are made.

Keywords: social marketing, policy-making, behavioral change, female genital mutilation, culture

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Authors: Elisavet Anastasiadou

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Global citizenship refers to an economic, social, political, and cultural interconnectedness, and it is inextricably intertwined with social justice, respect for human rights, peace, and a sense of responsibility to act on a local and global level. It aims to be transformative, enhance critical thinking and participation with pedagogical approaches based on social justice and democracy. The purpose of this study is to explore how Global Citizenship Education (GCE) is presented and implemented in two educational contexts, specifically in the curricula and pedagogical practices of primary education in Finland and Scotland. The impact of GCE is recognized as means for further development by institution such as and Finnish and Scottish curricula acknowledge the significance of GCE, emphasizing the student's ability to act and succeed in diverse and global communities. This comparative study should provide a good basis for further developing teaching practices based on informed understanding of how GCE is constrained or enabled from two different perspectives, extend the methodological applications of Practice Architectures and provide critical insights into GCE as a theoretical notion adopted by national and international educational policy. The study is directly connected with global citizenship aiming at future and societal change. The empirical work employs a multiple case study approach, including interviews and analysis of existing documents (textbook, curriculum). The data consists of the Finnish and Scottish curriculum. A systematic analysis of the curriculum in relation to GCE will offer insights into how the aims of GCE are presented and framed within the two contexts. This will be achieved using the theory of Practice Architectures. Curricula are official policy documentations (texts) that frame and envisage pedagogical practices. Practices, according to the theory of practice architectures, consist of sayings, doings, and relatings. Hence, even if the text analysis includes the semantic space (sayings) that are prefigured by the cultural-discursive arrangements and the relating prefigured by the socio-political arrangements, they will inevitably reveal information on the (doings) prefigured by the material-economic arrangements, as they hang together in practices. The results will assist educators in making changes to their teaching and enhance their self-conscious understanding of the history-making significance of their practices. It will also have a potential reform and focus on educationally relevant to such issues. Thus, the study will be able to open the ground for interventions and further research while it will consider the societal demands of a world in change.

Keywords: citizenhsip, curriculum, democracy, practices

Procedia PDF Downloads 203

Authors: Mingming Leng

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Wal-Mart has allocated considerable human resources for its quality assurance program, in which the largest retailer serves its supply chains as a quality gatekeeper. Asda Stores Ltd., the second largest supermarket chain in Britain, is now investing £27m in significantly increasing the frequency of quality control checks in its supply chains and thus enhancing quality across its fresh food business. Moreover, Tesco, the largest British supermarket chain, already constructed a quality assessment center to carry out its gatekeeping responsibility. Motivated by the above practices, we consider a supply chain in which a retailer plays the gatekeeping role in quality assurance by identifying defects among a manufacturer's products prior to selling them to consumers. The impact of a retailer's gatekeeping activity on pricing and quality assurance in a supply chain has not been investigated in the operations management area. We draw a number of managerial insights that are expected to help practitioners judiciously consider the quality gatekeeping effort at the retail level. As in practice, when the retailer identifies a defective product, she immediately returns it to the manufacturer, who then replaces the defect with a good quality product and pays a penalty to the retailer. If the retailer does not recognize a defect but sells it to a consumer, then the consumer will identify the defect and return it to the retailer, who then passes the returned 'unidentified' defect to the manufacturer. The manufacturer also incurs a penalty cost. Accordingly, we analyze a two-stage pricing and quality decision problem, in which the manufacturer and the retailer bargain over the manufacturer's average defective rate and wholesale price at the first stage, and the retailer decides on her optimal retail price and gatekeeping intensity at the second stage. We also compare the results when the retailer performs quality gatekeeping with those when the retailer does not. Our supply chain analysis exposes some important managerial insights. For example, the retailer's quality gatekeeping can effectively reduce the channel-wide defective rate, if her penalty charge for each identified de-fect is larger than or equal to the market penalty for each unidentified defect. When the retailer imple-ments quality gatekeeping, the change in the negotiated wholesale price only depends on the manufac-turer's 'individual' benefit, and the change in the retailer's optimal retail price is only related to the channel-wide benefit. The retailer is willing to take on the quality gatekeeping responsibility, when the impact of quality relative to retail price on demand is high and/or the retailer has a strong bargaining power. We conclude that the retailer's quality gatekeeping can help reduce the defective rate for consumers, which becomes more significant when the retailer's bargaining position in her supply chain is stronger. Retailers with stronger bargaining powers can benefit more from their quality gatekeeping in supply chains.

Keywords: bargaining, game theory, pricing, quality, supply chain

Procedia PDF Downloads 275

Authors: Gustavo Axel Elizalde-Velázquez

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Metformin is the first line of oral therapy to treat type II diabetes and is also employed as a treatment for other indications, such as polycystic ovary syndrome, cancer, and COVID-19. Recent data suggest it is the aspirin of the 21st century due to its antioxidant and anti-aging effects. However, increasingly current articles indicate its long-term consumption generates mitochondrial impairment. Up to date, it is known metformin increases the biogenesis of Alzheimer's amyloid peptides via up-regulating BACE1 transcription, but further information related to brain damage after its consumption is missing. Bearing in mind the above, this work aimed to establish whether or not chronic exposure to metformin may alter swimming behavior and induce neurotoxicity in Danio rerio adults. For this purpose, 250 Danio rerio grown-ups were assigned to six tanks of 50 L of capacity. Four of the six systems contained 50 fish, while the remaining two had 25 fish (≈1 male:1 female ratio). Every system with 50 fish was allocated one of the three metformin treatment concentrations (1, 20, and 40 μg/L), with one system as the control treatment. Systems with 25 fish, on the other hand, were used as positive controls for acetylcholinesterase (10 μg/L of Atrazine) and oxidative stress (3 μg/L of Atrazine). After four months of exposure, a mean of 32 fish (S.D. ± 2) per group of MET treatment survived, which were used for the evaluation of behavior with the Novel Tank test. Moreover, after the behavioral assessment, we aimed to collect the blood and brains of all fish from all treatment groups. For blood collection, fish were anesthetized with an MS-222 solution (150 mg/L), while for brain gathering, fish were euthanized using the hypothermic shock method (2–4 °C). Blood was employed to determine CASP3 activity and the percentage of apoptotic cells with the TUNEL assay, and brains were used to evaluate acetylcholinesterase activity, oxidative damage, and gene expression. After chronic exposure, MET-exposed fish exhibited less swimming activity when compared to control fish. Moreover, compared with the control group, MET significantly inhibited the activity of AChE and induced oxidative damage in the brain of fish. Concerning gene expression, MET significantly upregulated the expression of Nrf1, Nrf2, BAX, p53, BACE1, APP, PSEN1, and downregulated CASP3 and CASP9. Although MET did not overexpress the CASP3 gene, we saw a meaningful rise in the activity of this enzyme in the blood of fish exposed to MET compared to the control group, which we then confirmed by a high number of apoptotic cells in the TUNEL assay. To the best of our understanding, this is the first study that delivers evidence of oxidative impairment, apoptosis, AChE alteration, and overexpression of B- amyloid-related genes in the brain of fish exposed to metformin.

Keywords: AChE inhibition, CASP3 activity, NovelTank test, oxidative damage, TUNEL assay

Procedia PDF Downloads 81