Search results for: initial teacher education
2987 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
Procedia PDF Downloads 3642986 Effect of Two Different Method for Juice Processing on the Anthocyanins and Polyphenolics of Blueberry (Vaccinium corymbosum)
Authors: Onur Ercan, Buket Askin, Erdogan Kucukoner
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Blueberry (Vaccinium corymbosum, bluegold) has become popular beverage due to their nutritional values such as vitamins, minerals, and antioxidants. In the study, the effects of pressing, mashing, enzymatic treatment, and pasteurization on anthocyanins, colour, and polyphenolics of blueberry juice (BJ) were studied. The blueberry juice (BJ) was produced with two different methods that direct juice extraction (DJE) and mash treatment process (MTP) were applied. After crude blueberry juice (CBJ) production, the samples were first treated with commercial enzymes [Novoferm-61 (Novozymes A/S) (2–10 mL/L)], to break down the hydrocolloid polysaccharides, mainly pectin and starch. The enzymes were added at various concentrations. The highest transmittance (%) was obtained for Novoferm-61 at a concentration of 2 mL/L was 66.53%. After enzymatic treatment, clarification trials were applied to the enzymatically treated BJs with adding various amounts of bentonite (10%, w/v), gelatin (1%, w/v) and kiselsol (15%, v/v). The turbidities of the clarified samples were then determined. However, there was no significant differences between transmittances (%) for samples. For that, only enzymatic treatment was applied to the blueberry juice processing (DDBJ, depectinized direct blueberry juice). Based on initial pressing process made to evaluate press function, it was determined that pressing fresh blueberries with no other processing did not render adequate juice due to lack of liquefaction. Therefore, the blueberries were mash into small pieces (3 mm) and then enzymatic treatments and clarification trials were performed. Finally, both BJ samples were pasteurized. Compositional analyses, colour properties, polyphenols and antioxidant properties were compared. Enzymatic treatment caused significant reductions in ACN content (30%) in Direct Blueberry Juice Processing (DBJ), while there was a significant increasing in Mash Treatment Processing (MTP). Overall anthocyanin levels were higher intreated samples after each processing step in MTP samples, but polyphenolic levels were slightly higher for both processes (DBJ and MTP). There was a reduction for ACNs and polyphenolics only after pasteurization. It has a result that the methods for tried to blueberry juice is suitable into obtain fresh juice. In addition, we examined fruit juice during processing stages; anthocyanin, phenolic substance content and antioxidant activity are higher, and yield is higher in fruit juice compared to DBJ method in MTP method, the MTP method should be preferred in processing juice of blueberry into fruit juice.Keywords: anthocyanins, blueberry, depectinization, polyphenols
Procedia PDF Downloads 942985 Crime Victim Support Services in Bangladesh: An Analysis
Authors: Mohammad Shahjahan, Md. Monoarul Haque
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In the research work information and data were collected from both types of sources, direct and indirect. Numerological, qualitative and participatory analysis methods have been followed. There were two principal sources of collecting information and data. Firstly, the data provided by the service recipients (300 nos. of women and children victims) in the Victim Support Centre and service providing policemen, executives and staffs (60 nos.). Secondly, data collected from Specialists, Criminologists and Sociologists involved in victim support services through Consultative Interview, KII, Case Study and FGD etc. The initial data collection has been completed with the help of questionnaires as per strategic variations and with the help of guidelines. It is to be noted that the main objective of this research was to determine whether services provided to the victims for their facilities, treatment/medication and rehabilitation by different government/non-government organizations was veritable at all. At the same time socio-economic background and demographic characteristics of the victims have also been revealed through this research. The results of the study show that although the number of victims has increased gradually due to socio-economic, political and cultural realities in Bangladesh, the number of victim support centers has not increased as expected. Awareness among the victims about the effectiveness of the 8 centers working in this regard is also not up to the mark. Two thirds of the victims coming to get service were not cognizant regarding the victim support services at all before getting the service. Most of those who have finally been able to come under the services of the Victim Support Center through various means, have received sheltering (15.5%), medical services (13.32%), counseling services (13.10%) and legal aid (12.66%). The opportunity to stay in security custody and psycho-physical services were also notable. Usually, women and children from relatively poor and marginalized families of the society come to victim support center for getting services. Among the women, young unmarried women are the biggest victims of crime. Again, women and children employed as domestic workers are more affected. A number of serious negative impacts fall on the lives of the victims. Being deprived of employment opportunities (26.62%), suffering from psycho-somatic disorder (20.27%), carrying sexually transmitted diseases (13.92%) are among them. It seems apparent to urgently enact distinct legislation, increase the number of Victim Support Centers, expand the area and purview of services and take initiative to increase public awareness and to create mass movement.Keywords: crime, victim, support, Bangladesh
Procedia PDF Downloads 892984 Student Feedback and Its Impact on Fostering the Quality of Teaching at the Academia
Authors: S. Vanker, A. Aaver, A. Roio, L. Nuut
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To be sure about the effective and less effective/ineffective approaches to course instruction, we hold the opinion that the faculty members need regular feedback from their students in order to be aware of how well or unwell their teaching styles have worked when instructing the courses. It can be confirmed without a slightest hesitation that undergraduate students’ motivated-ness can be sustained when continually improving the quality of teaching and properly sequencing the academic courses both, in the curricula and timetables. At Estonian Aviation Academy, four different forms of feedback are used: Lecture monitoring, questionnaires for all students, study information system subject monitoring and direct feedback received by the lecturer. Questionnaires for all students are arranged once during a study year and separately for the first year and senior students. The results are discussed in academic departments together with student representatives, analyzed with the teaching staff and, if needed, improvements are suggested. In addition, a monitoring system is planned where a lecturer acts in both roles – as an observer and as the lecturer. This will foster better exchange of experience and through this help to make the whole study process more interesting.Keywords: learner motivation, feedback, student support, undergraduate education
Procedia PDF Downloads 3202983 Digital Library in India: Importance and Problem Issues in Present Days: A Conceptual Study
Authors: Mehtab Alam Ansari, Shamim Aktar Munshi
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The purpose of this paper is to find out the importance of digital libraries in Indian educational system, and also different types of problems faced by the digital library in modern age. This study uses both qualitative and quantitative approaches along with review of related literature. The conceptual and textual information related to the present study were collected from primary and secondary sources of information such as books and National and International journals etc. Websites were also used for collecting information. The study finds out that due to high demand of information resources so many digital libraries are established in India, e.g. IGNCA digital library, Digital Library of India, Archives of Indian Labour, Digital Library of Library and Information Science etc, and also it found that it is very helpful to the modern civilization. The digital library movement in India is rapidly increasing and the traditional libraries are now on their way to digitization in a phased manner. But digital library in India has failed to spread its root in each and every part. So many problems are facing to develop the digital libraries in present days. This study briefly explained the services, impact, and problems of digital libraries in Indian.Keywords: digital Libraries, India, information technology, education
Procedia PDF Downloads 5822982 Effect of Spirulina Supplementation on Growth Performance and Body Conformation of Two Omani Goat Breeds
Authors: Fahad Al Yahyaey, Ihab Shaat, Russell Bush
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This study was conducted at the Livestock Research Centre, Ministry of Agriculture and Fisheries, Oman, on two local goat breeds (Jabbali and Sahrawi) due to their importance to Omani livestock production and food security. The Jabbali is characterized by increased growth rates and a higher twinning rate, while the Sahrawi has increased milk production. The aim of the study was to investigate the effect of Spirulina supplementation on live weight (BWT), average daily gain (ADG), and body conformation measurements; chest girth (CG), wither height (WH), body length (BL), and body condition score (BCS). Thirty-six males (approximately nine-months-old and 16.44 ± 0.33 kg average of initial body weight) were used across an eleven-week study from November–February 2019-2020. Each breed was divided into three groups (n = 6/group) and fed one of three rations: (1) concentrate mixture (Control) with crude protein 14% and energy 11.97% MJ/kg DM; (2) the same concentrate feed with the addition of 2 gm /capita daily Spirulina platensis (Treatment 1) and (3) the same concentrate feed with the addition of 4 gm /capita daily Spirulina platensis (Treatment 2). Analysis of weekly data collections for all traits indicated a significant effect of feeding Spirulina on all the studied traits except WH and BL. Analysis of variance for fixed effects in this study (damage and kid birth type i.e., single, twin or triple) were not significant for all studied traits. However, the breed effect was highly significant (P < 0.001) on BWT, ADG, BCS, and CG traits. On the other hand, when the analysis was done for the treatment effect within breeds for ADG, the Sahrawi breed had a significant effect (P < 0.05) at 56.52, 85.51, and 85.50 g/day for control, treatment 1 and treatment 2, respectively. This is a 51% difference between the control and treatment 1 (2 gm /capita). Whereas for the Jabbali breed, the treatment effect was not significant for ADG (P =0.55), and the actual ADG was 104.59, 118.84, and 114.25 g/day for control, treatment 1, and treatment 2, respectively, providing a 14% difference between the control group and the treated group (4 gm /capita). These findings indicate using Spirulina supplementation in Omani goat diets is recommended at 2 gm per capita as there was no benefit in feeding at 4 gm per capita for either breed. Farmers feeding Spirulina supplementation to kids after weaning at six-months could increase their herd performance and growth rate and facilitate buck selection at an earlier age.Keywords: body conformation, goats, live weight, spirulina
Procedia PDF Downloads 1122981 Determination of Organizational Cynicism Levels of Health Care Workers
Authors: Murat İskender Aktaş, Selma Söyük
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The aim of this work is to specify the levels of organizational cynicism health workers. Organizational cynicism concept is evaluated in three sub-branches and these are cognitive, affective, and behavioral. The main objective of the work is to answer the questions about the relationship of demographic characteristics like sub-branches of cynicism and age, marital status, education level, total working hours, occupational groups and income levels. As works in our country are analyzed, there have been studies about cynicism in health and other sectors. However, there were no master’s thesis or organizational cynicism research found about the public health professionals. This is why the aim was chosen as to specify the levels of organizational cynicism of public health professionals. The average of the answers of the health workers to the questions about cynicism levels are 2.86. As organizational cynicism is evaluated according to the sub-branches, cognitive subscale average score is 3.21 affective subscale average score is 2.68 and behavioral subscale average score is counted as 2.67. As the results are analyzed, it is seen that the behavioral subscale has the highest average. This shows that the workers are often criticizing the internal complaints and organizational information with their friends out of the organization.Keywords: cynicism, organizational cynicism, health care workers
Procedia PDF Downloads 3392980 Spectral Mapping of Hydrothermal Alteration Minerals for Geothermal Exploration Using Advanced Spaceborne Thermal Emission and Reflection Radiometer Short Wave Infrared Data
Authors: Aliyu J. Abubakar, Mazlan Hashim, Amin B. Pour
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Exploiting geothermal resources for either power, home heating, Spa, greenhouses, industrial or tourism requires an initial identification of suitable areas. This can be done cost-effectively using remote sensing satellite imagery which has synoptic capabilities of covering large areas in real time and by identifying possible areas of hydrothermal alteration and minerals related to Geothermal systems. Earth features and minerals are known to have unique diagnostic spectral reflectance characteristics that can be used to discriminate them. The focus of this paper is to investigate the applicability of mapping hydrothermal alteration in relation to geothermal systems (thermal springs) at Yankari Park Northeastern Nigeria, using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite data for resource exploration. The ASTER Short Wave Infrared (SWIR) bands are used to highlight and discriminate alteration areas by employing sophisticated digital image processing techniques including image transformations and spectral mapping methods. Field verifications are conducted at the Yankari Park using hand held Global Positioning System (GPS) monterra to identify locations of hydrothermal alteration and rock samples obtained at the vicinity and surrounding areas of the ‘Mawulgo’ and ‘Wikki’ thermal springs. X-Ray Diffraction (XRD) results of rock samples obtained from the field validated hydrothermal alteration by the presence of indicator minerals including; Dickite, Kaolinite, Hematite and Quart. The study indicated the applicability of mapping geothermal anomalies for resource exploration in unmapped sparsely vegetated savanna environment characterized by subtle surface manifestations such as thermal springs. The results could have implication for geothermal resource exploration especially at the prefeasibility stages by narrowing targets for comprehensive surveys and in unexplored savanna regions where expensive airborne surveys are unaffordable.Keywords: geothermal exploration, image enhancement, minerals, spectral mapping
Procedia PDF Downloads 3632979 Intelligent Quality Management System on the Example оf Bread Baking
Authors: Irbulat Utepbergenov, Lyazzat Issabekova, Shara Toybayeva
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This article discusses quality management using the bread baking process as an example. The baking process must be strictly controlled and repeatable. Automation and monitoring of quality management systems can help. After baking bread, quality control of the finished product should be carried out. This may include an evaluation of appearance, weight, texture, and flavor. It is important to continuously work to improve processes and products based on data and feedback from the quality management system. A method and model of automated quality management and an intelligent automated management system based on intelligent technologies are proposed, which allow to automate the processes of QMS implementation and support and improve the validity, efficiency, and effectiveness of management decisions by automating a number of functions of decision makers and staff. This project is supported by the grant of the Ministry of Education and Science of the Republic of Kazakhstan (Zhas Galym project No. AR 13268939 Research and development of digital technologies to ensure consistency of the carriers of normative documents of the quality management system).Keywords: automated control system, quality management, efficiency evaluation, bakery oven, intelligent system
Procedia PDF Downloads 382978 Inclusion Complexes of Some Imidazoline Drugs with Cucurbit[N]Uril (N=7,8): Preparation, Characterization and Theoretical Calculations
Authors: Fakhreldin O. Suliman, Alia H. Al-Battashi
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This work explored the interaction of three different imidazoline drugs, naphazoline nitrate (NPH), oxymetazoline hydrochloride (OXY) and xylometazoline hydrochloride (XYL) with two different synthesized cucurbit[n]urils CB[n], cucurbit[7]uril (CB[7]) and cucuribit[8]uril (CB[8]). Three binary inclusion complexes have been investigated in solution and in the solid state. The solid complexes were obtained by lyophilization, whereas the physical mixtures of guests and hosts at a stoichiometric ratio of 1:1 were obtained for each drug. 1HNMR, electrospray ionization mass spectrometry (ESI-MS), and matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry was used to study the complexes prepared in aqueous media. The lyophilized solid complexes were characterized by Fourier transform-infrared spectroscopy (FT-IR), powder X-ray diffractometry (PXRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). MS, FT-IR and PXRD experimental results established in this work reveal that NPH, OXY and XYL molecules form stable inclusion complexes with the two hosts. The TGA and DSC confirmed the enhancement of the thermal stability of each drug and the production of a thermally stable solid complex. The 1HNMR has shown that the protons of the guests faced shifting in ppm and broadening of their peaks upon the formation of inclusion complexes with the selected CB[n]. The aromatic protons of the guest exhibited the highest changes in the chemical shifts and shape of the NMR peaks, suggesting their inclusion into the cavity of the CB[n]. The diffusion coefficients (D), developed from the diffusion-controlled NMR Spectroscopy (DOSY) measurements, for the complexation of the selected imidazoline drugs with CB[7] and CB[8], were decreased in the presence of hosts compared to the free guests indicating the formation of the guest-host adduct. Furthermore, we conducted molecular dynamic simulations and quantum mechanics calculations on these complexes. The results of the theoretical study corroborate the experimental findings and have also shed light on the mechanism of inclusion of the guests into the two hosts. This study generates initial data for potential drug delivery or drug formulation systems for these three selected imidazoline drug compounds based on their inclusion into the CB[n] cavities.Keywords: cucurbit[n]urils, imidazoline, inclusion complexes, molecular dynamics, DFT calculations, mass spectrometry
Procedia PDF Downloads 682977 Simulation of Focusing of Diamagnetic Particles in Ferrofluid Microflows with a Single Set of Overhead Permanent Magnets
Authors: Shuang Chen, Zongqian Shi, Jiajia Sun, Mingjia Li
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Microfluidics is a technology that small amounts of fluids are manipulated using channels with dimensions of tens to hundreds of micrometers. At present, this significant technology is required for several applications in some fields, including disease diagnostics, genetic engineering, and environmental monitoring, etc. Among these fields, manipulation of microparticles and cells in microfluidic device, especially separation, have aroused general concern. In magnetic field, the separation methods include positive and negative magnetophoresis. By comparison, negative magnetophoresis is a label-free technology. It has many advantages, e.g., easy operation, low cost, and simple design. Before the separation of particles or cells, focusing them into a single tight stream is usually a necessary upstream operation. In this work, the focusing of diamagnetic particles in ferrofluid microflows with a single set of overhead permanent magnets is investigated numerically. The geometric model of the simulation is based on the configuration of previous experiments. The straight microchannel is 24mm long and has a rectangular cross-section of 100μm in width and 50μm in depth. The spherical diamagnetic particles of 10μm in diameter are suspended into ferrofluid. The initial concentration of the ferrofluid c₀ is 0.096%, and the flow rate of the ferrofluid is 1.8mL/h. The magnetic field is induced by five identical rectangular neodymium−iron− boron permanent magnets (1/8 × 1/8 × 1/8 in.), and it is calculated by equivalent charge source (ECS) method. The flow of the ferrofluid is governed by the Navier–Stokes equations. The trajectories of particles are solved by the discrete phase model (DPM) in the ANSYS FLUENT program. The positions of diamagnetic particles are recorded by transient simulation. Compared with the results of the mentioned experiments, our simulation shows consistent results that diamagnetic particles are gradually focused in ferrofluid under magnetic field. Besides, the diamagnetic particle focusing is studied by varying the flow rate of the ferrofluid. It is in agreement with the experiment that the diamagnetic particle focusing is better with the increase of the flow rate. Furthermore, it is investigated that the diamagnetic particle focusing is affected by other factors, e.g., the width and depth of the microchannel, the concentration of the ferrofluid and the diameter of diamagnetic particles.Keywords: diamagnetic particle, focusing, microfluidics, permanent magnet
Procedia PDF Downloads 1302976 Cadmium Accumulation and Depuration Characteristics through Food Source of Cage-Cultivated Fish after Accidental Pollution in Longjiang River
Authors: Qianli Ma, Xuemin Zhao, Lingai Yao, Zhencheng Xu, Li Wang
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Heavy metal pollution accidents, frequently happened in this decade in China, severely threaten aquatic ecosystem and economy. In January 2012, a basin-scale accidental Cd pollution happened in Longjiang River in southwest China. Although water quality was recovered in short period by emergency treatment with flocculants, a large amount of contaminated cage-cultivated fish were left with the task of preventing or mitigating Cd contamination of fish. In this study, unpolluted Ctenopharyngodon idellus were fed by Cd-contaminated macrophytes for assessing the effect of Cd accumulation through food exposure, and the contaminated C. idellus were fed with Cd-free macrophytes for assessing the ability of Cd depuration. The on-site cultivation experiments were done in two sites of Lalang (S1, accidental Cd pollution originated) and Sancha (S2, a large amount of flocculants were added to accelerate Cd precipitation) in Longjiang river. Results showed that Cd content in fish muscle presented an increasing trend in the accumulation experiment. In S1, Cd content of fish muscle rose sharply from day 8 to day 18 with higher average Cd content in macrophytes and sediment, and kept in the range of 0.208-0.308 mg/kg afterward. In S2, Cd content of fish muscle rose gradually throughout the experiment and reached the maximum level of 0.285 mg/kg on day 76. The results of the depuration experiment showed that Cd content in fish muscle decreased and significant changes were observed in the first half time of the experiment. Meanwhile, fish with lower initial Cd content presented higher elimination constant. In S1, Cd content of fish significantly decreased from 0.713 to 0.304 mg/kg in 18 days and kept decreasing to 0.110 mg/kg in the end, and 84.6% of Cd content was eliminated. While in S2, there was a sharp decrease of Cd content of fish in 0-8 days from 0.355 mg/kg to 0.069 mg/kg. The total elimination percentage was 93.8% and 80.6% of which appeared in day 0-8. The elimination constant of fish in S2 was 0.03 which was higher than 0.02 in S1. Collectively, our results showed Cd could be absorbed through food exposure and accumulate in fish muscle, and the accumulated Cd in fish muscle can be excreted after isolated from the polluted food sources. This knowledge allows managers to assess health risk of Cd contaminated fish and minimize aquaculture loss when considering fish cultivation after accidental pollution.Keywords: accidental pollution, cadmium accumulation and depuration, cage-cultivated fish, environmental management, river
Procedia PDF Downloads 2532975 Learners and Teachers Experiences in Collaborative Learning
Authors: Bengi Sonyel, Kheder Kasem
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Nowadays technology is growing so fast. Everybody agrees that technology should be enhanced more in educational field in order to achieve maximum level of teaching and learning effectiveness. Collaborative learning is one of the most important subjects that have been discussed widely in the last 20 years. In this growing of technology and the widely spread of e-learning systems most of face-to-face processes are changing to be completely online base. Online collaborative learning considered one of the new feature that applied recently in some e-Learning systems but still there are much differences between face-to-face instance of collaborative learning and what really occur and happen in networked online environment.In this research we will compare face-to-face collaborative learning with online collaborative learning to define the key success for achieving course’s outcomes. We will also study the current teachers and students experience in today e-Learning systems, more specifically in online collaborative system and study them interaction to today’s technology that related to education. We will apply quantitative and qualitative research method in order to get accurate results. Finally we will gather all of our findings, analyze it and try to find the advantages and disadvantages as well as the current problems and possible solutions.Keywords: collaborative learning, learning by doing, technology, teachers, learners experiences
Procedia PDF Downloads 5252974 Use of Thrombolytics for Acute Myocardial Infarctions in Resource-Limited Settings, Globally: A Systematic Literature Review
Authors: Sara Zelman, Courtney Meyer, Hiren Patel, Lisa Philpotts, Sue Lahey, Thomas Burke
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Background: As the global burden of disease shifts from infectious diseases to noncommunicable diseases, there is growing urgency to provide treatment for time-sensitive illnesses, such as ST-Elevation Myocardial Infarctions (STEMIs). The standard of care for STEMIs in developed countries is Percutaneous Coronary Intervention (PCI). However, this is inaccessible in resource-limited settings. Before the discovery of PCI, Streptokinase (STK) and other thrombolytic drugs were first-line treatments for STEMIs. STK has been recognized as a cost-effective and safe treatment for STEMIs; however, in settings which lack access to PCI, it has not become the established second-line therapy. A systematic literature review was conducted to geographically map the use of STK for STEMIs in resource-limited settings. Methods: Our literature review group searched the databases Cinhal, Embase, Ovid, Pubmed, Web of Science, and WHO’s Index Medicus. The search terms included ‘thrombolytics’ AND ‘myocardial infarction’ AND ‘resource-limited’ and were restricted to human studies and papers written in English. A considerable number of studies came from Latin America; however, these studies were not written in English and were excluded. The initial search yielded 3,487 articles, which was reduced to 3,196 papers after titles were screened. Three medical professionals then screened abstracts, from which 291 articles were selected for full-text review and 94 papers were chosen for final inclusion. These articles were then analyzed and mapped geographically. Results: This systematic literature review revealed that STK has been used for the treatment of STEMIs in 33 resource-limited countries, with 18 of 94 studies taking place in India. Furthermore, 13 studies occurred in Pakistan, followed by Iran (6), Sri Lanka (5), Brazil (4), China (4), and South Africa (4). Conclusion: Our systematic review revealed that STK has been used for the treatment of STEMIs in 33 resource-limited countries, with the highest utilization occurring in India. This demonstrates that even though STK has high utility for STEMI treatment in resource-limited settings, it still has not become the standard of care. Future research should investigate the barriers preventing the establishment of STK use as second-line treatment after PCI.Keywords: cardiovascular disease, global health, resource-limited setting, ST-Elevation Myocardial Infarction, Streptokinase
Procedia PDF Downloads 1462973 Exploring Employee Experiences of Distributed Leadership in Consultancy SMEs
Authors: Mohamed Haffar, Ramdane Djebarni, Russell Evans
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Despite a growth in literature on distributed leadership, the majority of studies are centred on large public organisations particularly within the health and education sectors. The purpose of this study is to fill the gap in the literature by exploring employee experiences of distributed leadership within two commercial consultancy SME businesses in the UK and USA. The aim of the study informed an exploratory method of research to gather qualitative data drawn from semi-structured interviews involving a sample of employees in each organisation. A series of broad, open questions were used to explore the employees’ experiences; evidence of distributed leadership; and extant barriers and practices in each organisation. Whilst some of our findings aligned with patterns and practices in the existing literature, it importantly discovered some emergent themes that have not previously been recognised in the previous studies. Our investigation identified that whilst distributed leadership was in evidence in both organisations, the interviewees’ experience reported that it was sporadic and inconsistent. Moreover, non-client focused projects were reported to be less important and distributed leadership was found to be inconsistent or non-existent.Keywords: consultancy, distributed leadership, owner-manager, SME, entrepreneur
Procedia PDF Downloads 1232972 Nonlinear Modelling of Sloshing Waves and Solitary Waves in Shallow Basins
Authors: Mohammad R. Jalali, Mohammad M. Jalali
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The earliest theories of sloshing waves and solitary waves based on potential theory idealisations and irrotational flow have been extended to be applicable to more realistic domains. To this end, the computational fluid dynamics (CFD) methods are widely used. Three-dimensional CFD methods such as Navier-Stokes solvers with volume of fluid treatment of the free surface and Navier-Stokes solvers with mappings of the free surface inherently impose high computational expense; therefore, considerable effort has gone into developing depth-averaged approaches. Examples of such approaches include Green–Naghdi (GN) equations. In Cartesian system, GN velocity profile depends on horizontal directions, x-direction and y-direction. The effect of vertical direction (z-direction) is also taken into consideration by applying weighting function in approximation. GN theory considers the effect of vertical acceleration and the consequent non-hydrostatic pressure. Moreover, in GN theory, the flow is rotational. The present study illustrates the application of GN equations to propagation of sloshing waves and solitary waves. For this purpose, GN equations solver is verified for the benchmark tests of Gaussian hump sloshing and solitary wave propagation in shallow basins. Analysis of the free surface sloshing of even harmonic components of an initial Gaussian hump demonstrates that the GN model gives predictions in satisfactory agreement with the linear analytical solutions. Discrepancies between the GN predictions and the linear analytical solutions arise from the effect of wave nonlinearities arising from the wave amplitude itself and wave-wave interactions. Numerically predicted solitary wave propagation indicates that the GN model produces simulations in good agreement with the analytical solution of the linearised wave theory. Comparison between the GN model numerical prediction and the result from perturbation analysis confirms that nonlinear interaction between solitary wave and a solid wall is satisfactorilly modelled. Moreover, solitary wave propagation at an angle to the x-axis and the interaction of solitary waves with each other are conducted to validate the developed model.Keywords: Green–Naghdi equations, nonlinearity, numerical prediction, sloshing waves, solitary waves
Procedia PDF Downloads 2872971 Models, Methods and Technologies for Protection of Critical Infrastructures from Cyber-Physical Threats
Authors: Ivan Župan
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Critical infrastructure is essential for the functioning of a country and is designated for special protection by governments worldwide. Due to the increase in smart technology usage in every facet of the industry, including critical infrastructure, the exposure to malicious cyber-physical attacks has grown in the last few years. Proper security measures must be undertaken in order to defend against cyber-physical threats that can disrupt the normal functioning of critical infrastructure and, consequently the functioning of the country. This paper provides a review of the scientific literature of models, methods and technologies used to protect from cyber-physical threats in industries. The focus of the literature was observed from three aspects. The first aspect, resilience, concerns itself with the robustness of the system’s defense against threats, as well as preparation and education about potential future threats. The second aspect concerns security risk management for systems with cyber-physical aspects, and the third aspect investigates available testbed environments for testing developed models on scaled models of vulnerable infrastructure.Keywords: critical infrastructure, cyber-physical security, smart industry, security methodology, security technology
Procedia PDF Downloads 772970 Factors Predicting Food Insecurity in Older Thai Women
Authors: Noppawan Piaseu, Surat Komindr
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This study aimed to determine factors predicting food insecurity in older Thai women living in crowded urban communities. Through purposive sampling, 315 participants were recruited from community dwelling older women in Bangkok, Thailand. Data collection included interview from questionnaires and anthropometric measurement. Results showed that approximately half of the sample were 60-69 years old (51.1%), married (50.6%), obtained primary education (52.3%), had low family income (51.7%), lived in poor physical environment (49.9%) with normal body mass index (51.0%). Logistic regression analysis revealed that older women who were widowed/divorced/separated (OR = 1.804, 95% CI = 1.052-3.092, p = .032), who reported low family income (OR =.654, 95% CI = .523-.817, p < .001), and who had poor physical environment surrounding home (OR = 2.338, 95% CI = 1.057-5.171, p = .036) were more likely to have food insecurity. Results support that social and environmental factors are major factors predicting food insecurity in older women living in the urban community. Health professionals need to identify and monitor psychosocial, economic and environmental dimensions of food insecurity among them.Keywords: food insecurity, older women, urban communities, Thailand
Procedia PDF Downloads 4062969 Empirical Study From Final Exams of Graduate Courses in Computer Science to Demystify the Notion of an Average Software Engineer and Offer a Direction to Address Diversity of Professional Backgrounds of a Student Body
Authors: Alex Elentukh
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The paper is based on data collected from final exams administered during five years of teaching the graduate course in software engineering. The visualization instrument with four distinct personas has been used to improve the effectiveness of each class. The study offers a plethora of clues toward students' behavioral preferences. Diversity among students (professional background, physical proximity) is too significant to assume a single face of a learner. This is particularly true for a body of online graduate students in computer science. Conclusions of the study (each learner is unique, and each class is unique) are extrapolated to demystify the notion of an 'average software engineer.' An immediate direction for an educator is to ensure a course applies to a wide audience of very different individuals. On the other hand, a student should be clear about his/her abilities and preferences - to follow the most effective learning path.Keywords: K.3.2 computer and information science education, learner profiling, adaptive learning, software engineering
Procedia PDF Downloads 1032968 Estimation of Hydrogen Production from PWR Spent Fuel Due to Alpha Radiolysis
Authors: Sivakumar Kottapalli, Abdesselam Abdelouas, Christoph Hartnack
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Spent nuclear fuel generates a mixed field of ionizing radiation to the water. This radiation field is generally dominated by gamma rays and a limited flux of fast neutrons. The fuel cladding effectively attenuates beta and alpha particle radiation. Small fraction of the spent nuclear fuel exhibits some degree of fuel cladding penetration due to pitting corrosion and mechanical failure. Breaches in the fuel cladding allow the exposure of small volumes of water in the cask to alpha and beta ionizing radiation. The safety of the transport of radioactive material is assured by the package complying with the IAEA Requirements for the Safe Transport of Radioactive Material SSR-6. It is of high interest to avoid generation of hydrogen inside the cavity which may to an explosive mixture. The risk of hydrogen production along with other radiation gases should be analyzed for a typical spent fuel for safety issues. This work aims to perform a realistic study of the production of hydrogen by radiolysis assuming most penalizing initial conditions. It consists in the calculation of the radionuclide inventory of a pellet taking into account the burn up and decays. Westinghouse 17X17 PWR fuel has been chosen and data has been analyzed for different sets of enrichment, burnup, cycles of irradiation and storage conditions. The inventory is calculated as the entry point for the simulation studies of hydrogen production by radiolysis kinetic models by MAKSIMA-CHEMIST. Dose rates decrease strongly within ~45 μm from the fuel surface towards the solution(water) in case of alpha radiation, while the dose rate decrease is lower in case of beta and even slower in case of gamma radiation. Calculations are carried out to obtain spectra as a function of time. Radiation dose rate profiles are taken as the input data for the iterative calculations. Hydrogen yield has been found to be around 0.02 mol/L. Calculations have been performed for a realistic scenario considering a capsule containing the spent fuel rod. Thus, hydrogen yield has been debated. Experiments are under progress to validate the hydrogen production rate using cyclotron at > 5MeV (at ARRONAX, Nantes).Keywords: radiolysis, spent fuel, hydrogen, cyclotron
Procedia PDF Downloads 5212967 A Cross-Cultural Strategy for Managing an Organisation Located in a Diverse-Populated Community
Authors: Tsuu Faith Machingura, Daniel Madzanire, Doreen Nkala
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High employment opportunities in various towns in Zimbabwe attracted linguistically-diverse ethnic groups to settle therein. This movement, which largely was economically-induced, concocted diverse-populated communities in towns and in surrounding areas. Service provisions in such domains as education and business need to be diverse-sensitive. Prompted by the prevalence of diversity in present day business organisations, the study sought to suggest a cross-cultural strategy for managing an organisation located in a diverse-populated community. A case study research design was used. A sample of 10 participants consisting of five diverse business owners and five diverse clients was purposively drawn. Document analysis and key informant interviews were used to gather data. The study revealed that organisations that are located in diverse populated communities were shaped by the prevailing ethos. A diverse-sensitive managerial strategy was suggested as a pertinent cross-cultural managerial tool.Keywords: cross-cultural strategy, linguistic diversity, diverse-populated community, ethnic groups
Procedia PDF Downloads 712966 Financial Literacy as an Important Skill for Household Financial Decision Making
Authors: Rimac Smiljanic Ana, Pepur Sandra, Bulog Ivana
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Financial decision-making in the household is not simple, and it demands that the decision-maker has proper knowledge and skills. Usually, high uncertainty, risk, and stress surround household financial decision-making since it is extremely important and critical for household wealth accumulation and for the well-being of all household members. Generally, skilful people tend to have higher confidence in certain tasks they perform, and they achieve better results. Therefore, in the household context, the possession of certain skills by the ones who make financial decisions for the household is of particular importance. This paper addresses financial literacy as an important skill for household decision-making. Apart from financial literacy, the paper also considers other factors, such as employment, education, and age, as significant for household financial decision-making. The analysis is based on quantitative individual-level survey data. The data collection was conducted during January and February 2021 in Croatia through an online survey. To reach a wide variety of participants, the snowball sampling method was used. The result revealed interesting and somewhat puzzling results. Our results point to the importance of financial literacy skills for household decision-making.Keywords: skill, financial literacy, decision-making, household financijal decision making
Procedia PDF Downloads 972965 Absorptive Capabilities in the Development of Biopharmaceutical Industry: The Case of Bioprocess Development and Research Unit, National Polytechnic Institute
Authors: Ana L. Sánchez Regla, Igor A. Rivera González, María del Pilar Monserrat Pérez Hernández
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The ability of an organization to identify and get useful information from external sources, assimilate it, transform and apply to generate products or services with added value is called absorptive capacity. Absorptive capabilities contribute to have market opportunities to firms and get a leader position with respect to others competitors. The Bioprocess Development and Research Unit (UDIBI) is a Research and Development (R&D) laboratory that belongs to the National Polytechnic Institute (IPN), which is a higher education institute in Mexico. The UDIBI was created with the purpose of carrying out R and D activities for the Transferon®, a biopharmaceutical product developed and patented by IPN. The evolution of competence and scientific and technological platform made UDIBI expand its scope by providing technological services (preclínical studies and bio-compatibility evaluation) to the national pharmaceutical industry and biopharmaceutical industry. The relevance of this study is that those industries are classified as high scientific and technological intensity, and yet, after a review of the state of the art, there is only one study of absorption capabilities in biopharmaceutical industry with a similar scope to this research; in the case of Mexico, there is none. In addition to this, UDIBI belongs to a public university and its operation does not depend on the federal budget, but on the income generated by its external technological services. This fact represents a highly remarkable case in Mexico's public higher education context. This current doctoral research (2015-2019) is contextualized within a case study, its main objective is to identify and analyze the absorptive capabilities that characterise the UDIBI that allows it had become in a one of two third authorized laboratory by the sanitary authority in Mexico for developed bio-comparability studies to bio-pharmaceutical products. The development of this work in the field is divided into two phases. In a first phase, 15 interviews were conducted with the UDIBI personnel, covering management levels, heads of services, project leaders and laboratory personnel. These interviews were structured under a questionnaire, which was designed to integrate open questions and to a lesser extent, others, whose answers would be answered on a Likert-type rating scale. From the information obtained in this phase, a scientific article was made (in review and a proposal of presentation was submitted in different academic forums. A second stage will be made from the conduct of an ethnographic study within this organization under study that will last about 3 months. On the other hand, it is intended to carry out interviews with external actors around the UDIBI (suppliers, advisors, IPN officials, including contact with an academic specialized in absorption capacities to express their comments on this thesis. The inicial findings had shown two lines: i) exist institutional, technological and organizational management elements that encourage and/or limit the creation of absorption capacities in this scientific and technological laboratory and, ii) UDIBI has had created a set of multiple transfer technology of knowledge mechanisms which have had permitted to build a huge base of prior knowledge.Keywords: absorptive capabilities, biopharmaceutical industry, high research and development intensity industries, knowledge management, transfer of knowledge
Procedia PDF Downloads 2252964 Vibroacoustic Modulation of Wideband Vibrations and its Possible Application for Windmill Blade Diagnostics
Authors: Abdullah Alnutayfat, Alexander Sutin, Dong Liu
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Wind turbine has become one of the most popular energy productions. However, failure of blades and maintenance costs evolve into significant issues in the wind power industry, so it is essential to detect the initial blade defects to avoid the collapse of the blades and structure. This paper aims to apply modulation of high-frequency blade vibrations by low-frequency blade rotation, which is close to the known Vibro-Acoustic Modulation (VAM) method. The high-frequency wideband blade vibration is produced by the interaction of the surface blades with the environment air turbulence, and the low-frequency modulation is produced by alternating bending stress due to gravity. The low-frequency load of rotational wind turbine blades ranges between 0.2-0.4 Hz and can reach up to 2 Hz for strong wind. The main difference between this study and previous ones on VAM methods is the use of a wideband vibration signal from the blade's natural vibrations. Different features of the vibroacoustic modulation are considered using a simple model of breathing crack. This model considers the simple mechanical oscillator, where the parameters of the oscillator are varied due to low-frequency blade rotation. During the blade's operation, the internal stress caused by the weight of the blade modifies the crack's elasticity and damping. The laboratory experiment using steel samples demonstrates the possibility of VAM using a probe wideband noise signal. A cycle load with a small amplitude was used as a pump wave to damage the tested sample, and a small transducer generated a wideband probe wave. The received signal demodulation was conducted using the Detecting of Envelope Modulation on Noise (DEMON) approach. In addition, the experimental results were compared with the modulation index (MI) technique regarding the harmonic pump wave. The wideband and traditional VAM methods demonstrated similar sensitivity for earlier detection of invisible cracks. Importantly, employing a wideband probe signal with the DEMON approach speeds up and simplifies testing since it eliminates the need to conduct tests repeatedly for various harmonic probe frequencies and to adjust the probe frequency.Keywords: vibro-acoustic modulation, detecting of envelope modulation on noise, damage, turbine blades
Procedia PDF Downloads 992963 Creativity in Educational Realities: Theoretical Considerations
Authors: Cristina Costa-Lobo, Ana Campina, José Menezes
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Creativity implies originality, but originality does not imply the existence of creativity. Today, one of the challenges of the educational context is the development of educated, autonomous, prudent and competent citizens with a critical attitude, a well-founded questioning and a creative search for innovative alternatives and solutions. These supposedly cognitive capacities impose emotional analysis and decision making, and emotion is also considered as a creative act. Authors emphasize the importance of family and school in the creative manifestation of children and young people, and these agents can stimulate or impede creative expression. Thus, children entering the school system are faced with a barrier that blocks the externalization of this competence. This work deals with the implementation of specific strategies and promoters of an educational environment suitable for the development of creativity. The construct of creativity is discussed in a transdisciplinary perspective, and the importance of the construct is enhanced in psychoeducational practices, in challenging and multifaceted environments. It is assumed that the stimulation and early experience of creative thinking in an educational context are conditions that promote the development of problem-solving skills and future challenges.Keywords: creativity, education, psychology, pedagogy
Procedia PDF Downloads 2472962 Effectiveness of Powerpoint Presentations in Teaching Anatomy: A Student's Perspective
Authors: Vrinda Hari Ankolekar
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Introduction: The advancement of various audio-visual aids in the present era has led to progressive changes in education. Use of powerpoint presentations play a key role in anatomy to learn and understand a particular topic. As the subject of anatomy involves more of illustrations and demonstrations, powerpoint presentations become essential in conveying the necessary information. Objectives: To assess the students’ perspective about the use of powerpoint presentations in teaching anatomy.Method: A questionnaire was constructed and 55 students were asked to put forth their preferences for the powerpoint presentations or blackboard that would help them to understand the subject better. Results and conclusion: 30 voted PPT as better and effective tool to explain the subject efficiently. 35 chose PPT as more creative than Blackboard to create interest in the subject. 20 wanted to retain chalk and talk for teaching their subject instead of replacing it with PowerPoint. 36 felt chalk and talk as more useful and appropriate tool for teaching than PowerPoint. Only 25 felt chalk and talk relatively more boring than PowerPoint. 23 experienced more involvement and active participation in the class when chalk and talk is used as the teaching tool. 26 stated that chalk and talk has most of the features needed for teaching.One of the limitations of this study is that the sample size is drawn from one institution only and deals with the experience of one particular group of individuals.Keywords: chalk and board, powerpoint presentation, presentation skills, teaching technologies
Procedia PDF Downloads 4102961 Feeding Patterns and Diarrhea Incidence Among Children in Bangladesh: A Study Using Data from Demographic and Health Survey, 2014
Authors: Iqbal Ahmed Chowdhury
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Diarrhea is considered to be one of the influential factors of child death in Bangladesh. While it is known that diarrhea is a water-driven disease, due to the lack of studies, little is known about the extent to which various feeding patterns contribute to such an incidence. Our paper intends to fill this gap by looking into different feeding patterns and their influence on diarrhea incidence among children in Bangladesh. Using data collected for the Demographic and Health Survey, 2014, this paper reveals that feeding patterns can influence the diarrhea incidence among this group of children to a great extent. This paper finds that the incidence of diarrhea is likely to elevate if diarrhea-affected children are fed plain water from any source and any kind of juice. However, breastfeeding, feeding soup or clear broth, prescribed baby food, and clean water from a tube well tend to help fight diarrhea incidence among children in Bangladesh. The results are found to be consistent even after controlling for sociodemographic variables, including age and sex of children, age and education qualification of the parent, and the number of children in the family. The results of this study could contribute to treating diarrhea among children in Bangladesh as well as similar other countries in the world.Keywords: feeding patterns, diarrhea, Bangladesh, children
Procedia PDF Downloads 1092960 A Parametric Investigation into the Free Vibration and Flutter Characteristics of High Aspect Ratio Aircraft Wings Using Polynomial Distributions of Stiffness and Mass Properties
Authors: Ranjan Banerjee, W. D. Gunawardana
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The free vibration and flutter analysis plays a major part in aircraft design which is indeed, a mandatory requirement. In particular, high aspect ratio transport airliner wings are prone to free vibration and flutter problems that must be addressed during the design process as demanded by the airworthiness authorities. The purpose of this paper is to carry out a detailed free vibration and flutter analysis for a wide range of high aspect ratio aircraft wings and generate design curves to provide useful visions and understandings of aircraft design from an aeroelastic perspective. In the initial stage of the investigation, the bending and torsional stiffnesses of a number of transport aircraft wings are looked at and critically examined to see whether it is possible to express the stiffness distributions in polynomial form, but in a sufficiently accurate manner. A similar attempt is made for mass and mass moment of inertia distributions of the wing. Once the choice of stiffness and mass distributions in polynomial form is made, the high aspect ratio wing is idealised by a series of bending-torsion coupled beams from a structural standpoint. Then the dynamic stiffness method is applied to compute the natural frequencies and mode shape of the wing. Next the wing is idealised aerodynamically and to this end, unsteady aerodynamic of Theodorsen type is employed to represent the harmonically oscillating wing. Following this step, a normal mode method through the use of generalised coordinates is applied to formulate the flutter problem. In essence, the generalised mass, stiffness and aerodynamic matrices are combined to obtain the flutter matrix which is subsequently solved in the complex domain to determine the flutter speed and flutter frequency. In the final stage of the investigation, an exhaustive parametric study is carried out by varying significant wing parameters to generate design curves which help to predict the free vibration and flutter behaviour of high aspect ratio transport aircraft wings in a generic manner. It is in the aeroelastic context of aircraft design where the results are expected to be most useful.Keywords: high-aspect ratio wing, flutter, dynamic stiffness method, free vibration, aeroelasticity
Procedia PDF Downloads 2862959 Assessing the Prevalence of Taste Loss Among Adults Who Have Contracted SARS-CoV-2
Authors: Alketa Qafmolla, Mimoza Canga, Edit Xhajanka, Vergjini Mulo, Ramazan Isufi, Vito Antonio Malagnino
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COVID-19 is threatening the lives of people all over the world. A number of health problems, including oral health problems, have been linked to SARS-CoV-2 infection. Loss of taste is one of the initial symptoms presented by patients who have COVID-19. Purpose: The aim of the current study is to determine the prevalence of taste loss in young adults aged 18 to 26 who have contracted SARS-CoV-2. Materials and methods: This study is analytical cross-sectional research conducted in Albania from March 2023 to September 2023. Our research included a total of 157 students, of which 100 (63.7%) were female and 57 (36.3%) were male. They were divided into three age groups: 18-20, 21-23, and 24-26 years old. Students willingly agreed to participate in the current study and were assured that their participation would be kept anonymous. The study recorded no dropouts and was conducted in accordance with the Declaration of Helsinki. Statistical analysis was performed using IBM SPSS Statistics Version 23.0 on Microsoft Windows Linux, Chicago, IL, USA. The evaluation of data was done using analysis of variance (ANOVA), with a significance level set at P ≤ 0.05. Results: 113 (72%) of the participants reported loss of taste, while 44 (28%) did not experience any loss of taste. According to the study's data analysis, taste problems typically manifest over three days, with the lowest frequency occurring on the second day and the highest frequency occurring on the fifteenth. 68.7% of participants reported experiencing taste recovery after three weeks. The present study's findings demonstrated a substantial correlation between the duration of the individuals' COVID-19 infection and taste loss (P <0.0003). Based on the statistical analysis of the data, this study shows that there is no association between gender and loss of taste (P = 0.218). The participants reported having undergone the following treatments: prednisolone sodium phosphate (15 mg/5 mL daily), vitamin C (1000 mg), azithromycin (500 mg daily), oral vitamin D3 supplementation of 5000 IU daily, vitamin B12 (2.4 mcg daily), zinc 20 mg daily, Augmentin tablets (625 mg), and magnesium sulfate (4 g/100 mL). Conclusion: Within the limitations of this study conducted in Albania, it can be concluded that loss of taste was present in 72% of participants infected with COVID-19 and recovery was evident after three weeks.Keywords: adult, Albania, COVID-19, cross-sectional study, loss of taste
Procedia PDF Downloads 262958 CeO₂-Decorated Graphene-coated Nickel Foam with NiCo Layered Double Hydroxide for Efficient Hydrogen Evolution Reaction
Authors: Renzhi Qi, Zhaoping Zhong
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Under the dual pressure of the global energy crisis and environmental pollution, avoiding the consumption of non-renewable fossil fuels based on carbon as the energy carrier and developing and utilizing non-carbon energy carriers are the basic requirements for the future new energy economy. Electrocatalyst for water splitting plays an important role in building sustainable and environmentally friendly energy conversion. The oxygen evolution reaction (OER) is essentially limited by the slow kinetics of multi-step proton-electron transfer, which limits the efficiency and cost of water splitting. In this work, CeO₂@NiCo-NRGO/NF hybrid materials were prepared using nickel foam (NF) and nitrogen-doped reduced graphene oxide (NRGO) as conductive substrates by multi-step hydrothermal method and were used as highly efficient catalysts for OER. The well-connected nanosheet array forms a three-dimensional (3D) network on the substrate, providing a large electrochemical surface area with abundant catalytic active sites. The doping of CeO₂ in NiCo-NRGO/NF electrocatalysts promotes the dispersion of substances and its synergistic effect in promoting the activation of reactants, which is crucial for improving its catalytic performance against OER. The results indicate that CeO₂@NiCo-NRGO/NF only requires a lower overpotential of 250 mV to drive the current density of 10 mA cm-2 for an OER reaction of 1 M KOH, and exhibits excellent stability at this current density for more than 10 hours. The double layer capacitance (Cdl) values show that CeO₂@NiCo-NRGO/NF significantly affects the interfacial conductivity and electrochemically active surface area. The hybrid structure could promote the catalytic performance of oxygen evolution reaction, such as low initial potential, high electrical activity, and excellent long-term durability. The strategy for improving the catalytic activity of NiCo-LDH can be used to develop a variety of other electrocatalysts for water splitting.Keywords: CeO₂, reduced graphene oxide, NiCo-layered double hydroxide, oxygen evolution reaction
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