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Commenced in January 2007
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Edition: International
Paper Count: 2034

Search results for: refinish clear coat

294 The Impact of Speech Style on the Production of Spanish Vowels by Spanish-English Bilinguals and Spanish Monolinguals

Authors: Vivian Franco

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There has been a great deal of research about vowel production of second language learners of Spanish, vowel variation across Spanish dialects, and more recently, research related to Spanish heritage speakers’ vowel production based on speech style. However, there is little investigation reported on Spanish heritage speakers’ vowel production in regard to task modality by incorporating own comparison groups of monolinguals and late bilinguals. Thus, the present study investigates the influence of speech style on Spanish heritage speakers’ vowel production by comparing Spanish-English early and late bilinguals and Spanish monolinguals. The study was guided by the following research question: How do early bilinguals (heritage speakers) differ/relate to advanced L2 speakers of Spanish (late bilinguals) and Spanish monolinguals in their vowel quality (acoustic distribution) and quantity (duration) based on speech style? The participants were a total of 11 speakers of Spanish: 7 early Spanish-English bilinguals with a similar linguistic background (simultaneous bilinguals of the second generation); 2 advanced L2 speakers of Spanish; and 2 Spanish monolinguals from Mexico. The study consisted of two tasks. The first one adopted a semi-spontaneous style by a solicited narration of life experiences and a description of a favorite movie with the purpose to collect spontaneous speech. The second task was a reading activity in which the participants read two paragraphs of a Mexican literary essay 'La nuez.' This task aimed to obtain a more controlled speech style. From this study, it can be concluded that early bilinguals and monolinguals show a smaller formant vowel space overall compared to the late bilinguals in both speech styles. In terms of formant values by stress, the early bilinguals and the late bilinguals resembled in the semi-spontaneous speech style as their unstressed vowel space overlapped with that of the unstressed vowels different from the monolinguals who displayed a slightly reduced unstressed vowel space. For the controlled data, the early bilinguals were similar to the monolinguals as their stressed and unstressed vowel spaces overlapped in comparison to the late bilinguals who showed a more clear reduction of unstressed vowel space. In regard to stress, the monolinguals revealed longer vowel duration overall. However, findings of duration by stress showed that the early bilinguals and the monolinguals remained stable with shorter values of unstressed vowels in the semi-spontaneous data and longer duration in the controlled data when compared to the late bilinguals who displayed opposite results. These findings suggest an implication for Spanish heritage speakers and L2 Spanish vowels research as it has been frequently argued that Spanish bilinguals differ from the Spanish monolinguals by their vowel reduction and centralized vowel space influenced by English. However, some Spanish varieties are characterized by vowel reduction especially in certain phonetic contexts so that some vowels present more weakening than others. Consequently, it would not be conclusive to affirm an English influence on the Spanish of these bilinguals.

Keywords: Spanish-English bilinguals, Spanish monolinguals, spontaneous and controlled speech, vowel production.

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293 Educational Infrastructure a Barrier for Teaching and Learning Architecture

Authors: Alejandra Torres-Landa López

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Introduction: Can architecture students be creative in spaces conformed by an educational infrastructure build with paradigms of the past?, this question and others related are answered in this paper as it presents the PhD research: An anthropic conflict in Mexican Higher Education Institutes, problems and challenges of the educational infrastructure in teaching and learning History of Architecture. This research was finished in 2013 and is one of the first studies conducted nationwide in Mexico that analysis the educational infrastructure impact in learning architecture; its objective was to identify which elements of the educational infrastructure of Mexican Higher Education Institutes where architects are formed, hinder or contribute to the teaching and learning of History of Architecture; how and why it happens. The methodology: A mixed methodology was used combining quantitative and qualitative analysis. Different resources and strategies for data collection were used, such as questionnaires for students and teachers, interviews to architecture research experts, direct observations in Architecture classes, among others; the data collected was analyses using SPSS and MAXQDA. The veracity of the quantitative data was supported by the Cronbach’s Alpha Coefficient, obtaining a 0.86, figure that gives the data enough support. All the above enabled to certify the anthropic conflict in which Mexican Universities are. Major findings of the study: Although some of findings were probably not unknown, they haven’t been systematized and analyzed with the depth to which it’s done in this research. So, it can be said, that the educational infrastructure of most of the Higher Education Institutes studied, is a barrier to the educational process, some of the reasons are: the little morphological variation of space, the inadequate control of lighting, noise, temperature, equipment and furniture, the poor or none accessibility for disable people; as well as the absence, obsolescence and / or insufficiency of information technologies are some of the issues that generate an anthropic conflict understanding it as the trouble that teachers and students have to relate between them, in order to achieve significant learning). It is clear that most of the educational infrastructure of Mexican Higher Education Institutes is anchored to paradigms of the past; it seems that they respond to the previous era of industrialization. The results confirm that the educational infrastructure of Mexican Higher Education Institutes where architects are formed, is perceived as a "closed container" of people and data; infrastructure that becomes a barrier to teaching and learning process. Conclusion: The research results show it's time to change the paradigm in which we conceive the educational infrastructure, it’s time to stop seen it just only as classrooms, workshops, laboratories and libraries, as it must be seen from a constructive, urban, architectural and human point of view, taking into account their different dimensions: physical, technological, documental, social, among others; so the educational infrastructure can become a set of elements that organize and create spaces where ideas and thoughts can be shared; to be a social catalyst where people can interact between each other and with the space itself.

Keywords: educational infrastructure, impact of space in learning architecture outcomes, learning environments, teaching architecture, learning architecture

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292 Roads and Agriculture: Impacts of Connectivity in Peru

Authors: Julio Aguirre, Yohnny Campana, Elmer Guerrero, Daniel De La Torre Ugarte

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A well-developed transportation network is a necessary condition for a country to derive full benefits from good trade and macroeconomic policies. Road infrastructure plays a key role in the economic development of rural areas of developing countries; where agriculture is the main economic activity. The ability to move agricultural production from the place of production to the market, and then to the place of consumption, greatly influence the economic value of farming activities, and of the resources involved in the production process, i.e., labor and land. Consequently, investment in transportation networks contributes to enhance or overcome the natural advantages or disadvantages that topography and location have imposed over the agricultural sector. This is of particular importance when dealing with countries, like Peru, with a great topographic diversity. The objective of this research is to estimate the impacts of road infrastructure on the performance of the agricultural sector. Specific variables of interest are changes in travel time, shifts of production for self-consumption to production for the market, changes in farmers income, and impacts on the diversification of the agricultural sector. In the study, a cross-section model with instrumental variables is the central methodological instrument. The data is obtained from agricultural and transport geo-referenced databases, and the instrumental variable specification utilized is based on the Kruskal algorithm. The results show that the expansion of road connectivity reduced farmers' travel time by an average of 3.1 hours and the proportion of output sold in the market increases by up to 40 percentage points. The increase in connectivity has an unexpected increase in the districts index of diversification of agricultural production. The results are robust to the inclusion of year and region fixed-effects, and to control for geography (i.e., slope and altitude), population variables, and mining activity. Other results are also very eloquent. For example, a clear positive impact can be seen in access to local markets, but this does not necessarily correlate with an increase in the production of the sector. This can be explained by the fact that agricultural development not only requires provision of roads but additional complementary infrastructure and investments intended to provide the necessary conditions so that producers can offer quality products (improved management practices, timely maintenance of irrigation infrastructure, transparent management of water rights, among other factors). Therefore, complementary public goods are needed to enhance the effects of roads on the welfare of the population, beyond enabling them to increase their access to markets.

Keywords: agriculture devolepment, market access, road connectivity, regional development

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291 Development of an Automatic Computational Machine Learning Pipeline to Process Confocal Fluorescence Images for Virtual Cell Generation

Authors: Miguel Contreras, David Long, Will Bachman

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Background: Microscopy plays a central role in cell and developmental biology. In particular, fluorescence microscopy can be used to visualize specific cellular components and subsequently quantify their morphology through development of virtual-cell models for study of effects of mechanical forces on cells. However, there are challenges with these imaging experiments, which can make it difficult to quantify cell morphology: inconsistent results, time-consuming and potentially costly protocols, and limitation on number of labels due to spectral overlap. To address these challenges, the objective of this project is to develop an automatic computational machine learning pipeline to predict cellular components morphology for virtual-cell generation based on fluorescence cell membrane confocal z-stacks. Methods: Registered confocal z-stacks of nuclei and cell membrane of endothelial cells, consisting of 20 images each, were obtained from fluorescence confocal microscopy and normalized through software pipeline for each image to have a mean pixel intensity value of 0.5. An open source machine learning algorithm, originally developed to predict fluorescence labels on unlabeled transmitted light microscopy cell images, was trained using this set of normalized z-stacks on a single CPU machine. Through transfer learning, the algorithm used knowledge acquired from its previous training sessions to learn the new task. Once trained, the algorithm was used to predict morphology of nuclei using normalized cell membrane fluorescence images as input. Predictions were compared to the ground truth fluorescence nuclei images. Results: After one week of training, using one cell membrane z-stack (20 images) and corresponding nuclei label, results showed qualitatively good predictions on training set. The algorithm was able to accurately predict nuclei locations as well as shape when fed only fluorescence membrane images. Similar training sessions with improved membrane image quality, including clear lining and shape of the membrane, clearly showing the boundaries of each cell, proportionally improved nuclei predictions, reducing errors relative to ground truth. Discussion: These results show the potential of pre-trained machine learning algorithms to predict cell morphology using relatively small amounts of data and training time, eliminating the need of using multiple labels in immunofluorescence experiments. With further training, the algorithm is expected to predict different labels (e.g., focal-adhesion sites, cytoskeleton), which can be added to the automatic machine learning pipeline for direct input into Principal Component Analysis (PCA) for generation of virtual-cell mechanical models.

Keywords: cell morphology prediction, computational machine learning, fluorescence microscopy, virtual-cell models

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290 Modelling of Air-Cooled Adiabatic Membrane-Based Absorber for Absorption Chillers Using Low Temperature Solar Heat

Authors: M. Venegas, M. De Vega, N. García-Hernando

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Absorption cooling chillers have received growing attention over the past few decades as they allow the use of low-grade heat to produce the cooling effect. The combination of this technology with solar thermal energy in the summer period can reduce the electricity consumption peak due to air-conditioning. One of the main components, the absorber, is designed for simultaneous heat and mass transfer. Usually, shell and tubes heat exchangers are used, which are large and heavy. Cooling water from a cooling tower is conventionally used to extract the heat released during the absorption and condensation processes. These are clear inconvenient for the generalization of the absorption technology use, limiting its benefits in the contribution to the reduction in CO2 emissions, particularly for the H2O-LiBr solution which can work with low heat temperature sources as provided by solar panels. In the present work a promising new technology is under study, consisting in the use of membrane contactors in adiabatic microchannel mass exchangers. The configuration here proposed consists in one or several modules (depending on the cooling capacity of the chiller) that contain two vapour channels, separated from the solution by adjacent microporous membranes. The solution is confined in rectangular microchannels. A plastic or synthetic wall separates the solution channels between them. The solution entering the absorber is previously subcooled using ambient air. In this way, the need for a cooling tower is avoided. A model of the configuration proposed is developed based on mass and energy balances and some correlations were selected to predict the heat and mass transfer coefficients. The concentration and temperatures along the channels cannot be explicitly determined from the set of equations obtained. For this reason, the equations were implemented in a computer code using Engineering Equation Solver software, EES™. With the aim of minimizing the absorber volume to reduce the size of absorption cooling chillers, the ratio between the cooling power of the chiller and the absorber volume (R) is calculated. Its variation is shown along the solution channels, allowing its optimization for selected operating conditions. For the case considered the solution channel length is recommended to be lower than 3 cm. Maximum values of R obtained in this work are higher than the ones found in optimized horizontal falling film absorbers using the same solution. Results obtained also show the variation of R and the chiller efficiency (COP) for different ambient temperatures and desorption temperatures typically obtained using flat plate solar collectors. The configuration proposed of adiabatic membrane-based absorber using ambient air to subcool the solution is a good technology to reduce the size of the absorption chillers, allowing the use of low temperature solar heat and avoiding the need for cooling towers.

Keywords: adiabatic absorption, air-cooled, membrane, solar thermal energy

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289 Perception of the End of a Same Sex Relationship and Preparation towards It: A Qualitative Research about Anticipation, Coping and Conflict Management against the Backdrop of Partial Legal Recognition

Authors: Merav Meiron-Goren, Orna Braun-Lewensohn, Tal Litvak-Hirsh

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In recent years, there has been an increasing tendency towards separation and divorce in relationships. Nevertheless, many couples in a first marriage do not anticipate this as a probable possibility and do not make any preparation for it. Same sex couples establishing a family encounter a much more complicated situation than do heterosexual couples. Although there is a trend towards legal recognition of same sex marriage, many countries, including Israel, do not recognize it. The absence of legal recognition or the existence of partial recognition creates complexity for these couples. They have to fight for their right to establish a family, like the recognition of the biological child of a woman, as a child of her woman spouse too, or the option of surrogacy for a male couple who want children, and more. The lack of legal recognition is burden on the lives of these couples. In the absence of clear norms regarding the conduct of the family unit, the couples must define for themselves the family structure, and deal with everyday dilemmas that lack institutional solutions. This may increase the friction between the two couple members, and it is one of the factors that make it difficult for them to maintain the relationship. This complexity exists, perhaps even more so, in separation. The end of relationship is often accompanied by a deep crisis, causing pain and stress. In most cases, there are also other conflicts that must be settled. These are more complicated when rights are in doubt or do not exist at all. Complex issues for separating same sex couples may include matters of property, recognition of parenthood, and care and support for the children. The significance of the study is based on the fact that same sex relationships are becoming more and more widespread, and are an integral part of the society. Even so, there is still an absence of research focusing on such relationships and their ending. The objective of the study is to research the perceptions of same sex couples regarding the possibility of separation, preparing for it, conflict management and resolving disputes through the separation process. It is also important to understand the point of view of couples that have gone through separation, how they coped with the emotional and practical difficulties involved in the separation process. The doctoral research will use a qualitative research method in a phenomenological approach, based on semi-structured in-depth interviews. The interviewees will be divided into three groups- at the beginning of a relationship, during the separation crisis and after separation, with a time perspective, with about 10 couples from each group. The main theoretical model serving as the basis of the study will be the Lazarus and Folkman theory of coping with stress. This model deals with the coping process, including cognitive appraisal of an experience as stressful, appraisal of the coping resources, and using strategies of coping. The strategies are divided into two main groups, emotion-focused forms of coping and problem-focused forms of coping.

Keywords: conflict management, coping, legal recognition, same-sex relationship, separation

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288 Acute Neurophysiological Responses to Resistance Training; Evidence of a Shortened Super Compensation Cycle and Early Neural Adaptations

Authors: Christopher Latella, Ashlee M. Hendy, Dan Vander Westhuizen, Wei-Peng Teo

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Introduction: Neural adaptations following resistance training interventions have been widely investigated, however the evidence regarding the mechanisms of early adaptation are less clear. Understanding neural responses from an acute resistance training session is pivotal in the prescription of frequency, intensity and volume in applied strength and conditioning practice. Therefore the primary aim of this study was to investigate the time course of neurophysiological mechanisms post training against current super compensation theory, and secondly, to examine whether these responses reflect neural adaptations observed with resistance training interventions. Methods: Participants (N=14) completed a randomised, counterbalanced crossover study comparing; control, strength and hypertrophy conditions. The strength condition involved 3 x 5RM leg extensions with 3min recovery, while the hypertrophy condition involved 3 x 12 RM with 60s recovery. Transcranial magnetic stimulation (TMS) and peripheral nerve stimulation were used to measure excitability of the central and peripheral neural pathways, and maximal voluntary contraction (MVC) to quantify strength changes. Measures were taken pre, immediately post, 10, 20 and 30 mins and 1, 2, 6, 24, 48, 72 and 96 hrs following training. Results: Significant decreases were observed at post, 10, 20, 30 min, 1 and 2 hrs for both training groups compared to control group for force, (p <.05), maximal compound wave; (p < .005), silent period; (p < .05). A significant increase in corticospinal excitability; (p < .005) was observed for both groups. Corticospinal excitability between strength and hypertrophy groups was near significance, with a large effect (η2= .202). All measures returned to baseline within 6 hrs post training. Discussion: Neurophysiological mechanisms appear to be significantly altered in the period 2 hrs post training, returning to homeostasis by 6 hrs. The evidence suggests that the time course of neural recovery post resistance training occurs 18-40 hours shorter than previous super compensation models. Strength and hypertrophy protocols showed similar response profiles with current findings suggesting greater post training corticospinal drive from hypertrophy training, despite previous evidence that strength training requires greater neural input. The increase in corticospinal drive and decrease inl inhibition appear to be a compensatory mechanism for decreases in peripheral nerve excitability and maximal voluntary force output. The changes in corticospinal excitability and inhibition are akin to adaptive processes observed with training interventions of 4 wks or longer. It appears that the 2 hr recovery period post training is the most influential for priming further neural adaptations with resistance training. Secondly, the frequency of prescribed resistance sessions can be scheduled closer than previous super compensation theory for optimal strength gains.

Keywords: neural responses, resistance training, super compensation, transcranial magnetic stimulation

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287 Political Skills in Social Management and Responsibility of Media Studies

Authors: Musa Miah

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Society and social activities are directly governed by political sociology. Political sociology has an impact on the whole of human society, the interrelationships of people in society, social responsibilities and duties, the nature of society, society and culture of different countries, conducting social activities, social change and social development. Through this, the correct knowledge and decision are made by analyzing the complexities of society in different ways. In modern civilized society, people need to get accurate knowledge about how they live, their behavior, customs and principles. The need for political sociology is undeniable, even if new plans are to be adopted for the development of society. The importance of practicing political sociology is immense if any country, nation, or society is to move forward on the path of sustainable development. Research has shown that political sociology is an essential aspect of the social impact of development, sociological analysis of poverty or underdevelopment, development of human values in individual life. The importance of political sociology for knowing the overall aspect of society is undeniable. Because, to know about social problems, to identify social problems, to find the cause of any social problem, one needs to know political sociology. Apart from knowing about the class structure of the society, people of different classes and professions live in the society. It is possible to gain knowledge about. He is also involved in various societies, communities and groups in the country and abroad. Therefore, research has shown that in order to successfully solve any task of the society, it is necessary to know the society in full. Media Studies: Media studies are directly related to socialization. Media strategy has had a positive impact on the management and direction of society. At present, Media Studies in Bangladesh is working towards providing opportunities for up-to-date and quality higher education. Introduced Department of Journalism, Communication and Media Studies in different universities of Bangladesh. The department has gained immense popularity since its inception. Here the top degree holders, as well as eminent editors, senior journalists, writers and researchers, are giving their opinions. Now there is ample scope for research in newspapers, magazines, radio, television and online media as well as outside of work as an advertising-documentary filmmaker or in domestic and foreign NGOs or other corporate organizations. According to the study, media studies have had a positive impact on the media in Bangladesh, especially television channels, the expansion and development of online media and the creation of clear ideas about communication, journalism and the media. Workshops, seminars and discussions are being held on contemporary national and international issues in addition to theoretical concepts. Journalism, communication and mass media are quite exceptional and challenging compared to the traditional subjects considering the present times. In this regard, there is a unique opportunity to build a modern society with taste and personality without mere employment.

Keywords: Bangladesh, Dhaka, social activities, political sociology

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286 Effect of Two Types of Shoe Insole on the Dynamics of Lower Extremities Joints in Individuals with Leg Length Discrepancy during Stance Phase of Walking

Authors: Mansour Eslami, Fereshte Habibi

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Limb length discrepancy (LLD), or anisomeric, is defined as a condition in which paired limbs are noticeably unequal. Individuals with LLD during walking use compensatory mechanisms to dynamically lengthen the short limb and shorten the long limb to minimize the displacement of the body center of mass and consequently reduce body energy expenditure. Due to the compensatory movements created, LLD greater than 1 cm increases the odds of creating lumbar problems and hip and knee osteoarthritis. Insoles are non-surgical therapies that are recommended to improve the walking pattern, pain and create greater symmetry between the two lower limbs. However, it is not yet clear what effect insoles have on the variables related to injuries during walking. The aim of the present study was to evaluate the effect of internal and external heel lift insoles on pelvic kinematic in sagittal and frontal planes and lower extremity joint moments in individuals with mild leg length discrepancy during the stance phase of walking. Biomechanical data of twenty-eight men with structural leg length discrepancy of 10-25 mm were collected while they walked under three conditions: shoes without insole (SH), with internal heel lift insoles (IHLI) in shoes, and with external heal lift insole (EHLI). The tests were performed for both short and long legs. The pelvic kinematic and joint moment were measured with a motion capture system and force plate. Five walking trials were performed for each condition. The average value of five successful trials was used for further statistical analysis. Repeated measures ANCOVA with Bonferroni post hoc test were used for between-group comparisons (p ≤ 0.05). In both internal and external heel lift insoles (IHLI, EHLI), there was a significant decrease in the peak values of lateral and anterior pelvic tilts of the long leg, hip, and knee moments of a long leg and ankle moment of short leg (p ≤ 0.05). Furthermore, significant increases in peak values of lateral and anterior pelvic tilt of short leg in IHLI and EHLI were observed as compared to Shoe (SH) condition (p ≤ 0.01). In addition, a significant difference was observed between the IHLI and EHLI conditions in peak anterior pelvic tilt of long leg and plantar flexor moment of short leg (p=0.04; p= 0.04 respectively). Our findings indicate that both IHLI and EHLI can play an important role in controlling excessive pelvic movements in the sagittal and frontal planes in individuals with mild LLD during walking. Furthermore, the EHLI may have a better effect in preventing musculoskeletal injuries compared to the IHLI.

Keywords: kinematic, leg length discrepancy, shoe insole, walking

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285 VISMA: A Method for System Analysis in Early Lifecycle Phases

Authors: Walter Sebron, Hans Tschürtz, Peter Krebs

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The choice of applicable analysis methods in safety or systems engineering depends on the depth of knowledge about a system, and on the respective lifecycle phase. However, the analysis method chain still shows gaps as it should support system analysis during the lifecycle of a system from a rough concept in pre-project phase until end-of-life. This paper’s goal is to discuss an analysis method, the VISSE Shell Model Analysis (VISMA) method, which aims at closing the gap in the early system lifecycle phases, like the conceptual or pre-project phase, or the project start phase. It was originally developed to aid in the definition of the system boundary of electronic system parts, like e.g. a control unit for a pump motor. Furthermore, it can be also applied to non-electronic system parts. The VISMA method is a graphical sketch-like method that stratifies a system and its parts in inner and outer shells, like the layers of an onion. It analyses a system in a two-step approach, from the innermost to the outermost components followed by the reverse direction. To ensure a complete view of a system and its environment, the VISMA should be performed by (multifunctional) development teams. To introduce the method, a set of rules and guidelines has been defined in order to enable a proper shell build-up. In the first step, the innermost system, named system under consideration (SUC), is selected, which is the focus of the subsequent analysis. Then, its directly adjacent components, responsible for providing input to and receiving output from the SUC, are identified. These components are the content of the first shell around the SUC. Next, the input and output components to the components in the first shell are identified and form the second shell around the first one. Continuing this way, shell by shell is added with its respective parts until the border of the complete system (external border) is reached. Last, two external shells are added to complete the system view, the environment and the use case shell. This system view is also stored for future use. In the second step, the shells are examined in the reverse direction (outside to inside) in order to remove superfluous components or subsystems. Input chains to the SUC, as well as output chains from the SUC are described graphically via arrows, to highlight functional chains through the system. As a result, this method offers a clear and graphical description and overview of a system, its main parts and environment; however, the focus still remains on a specific SUC. It helps to identify the interfaces and interfacing components of the SUC, as well as important external interfaces of the overall system. It supports the identification of the first internal and external hazard causes and causal chains. Additionally, the method promotes a holistic picture and cross-functional understanding of a system, its contributing parts, internal relationships and possible dangers within a multidisciplinary development team.

Keywords: analysis methods, functional safety, hazard identification, system and safety engineering, system boundary definition, system safety

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284 Diagnosis of Intermittent High Vibration Peaks in Industrial Gas Turbine Using Advanced Vibrations Analysis

Authors: Abubakar Rashid, Muhammad Saad, Faheem Ahmed

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This paper provides a comprehensive study pertaining to diagnosis of intermittent high vibrations on an industrial gas turbine using detailed vibrations analysis, followed by its rectification. Engro Polymer & Chemicals Limited, a Chlor-Vinyl complex located in Pakistan has a captive combined cycle power plant having two 28 MW gas turbines (make Hitachi) & one 15 MW steam turbine. In 2018, the organization faced an issue of high vibrations on one of the gas turbines. These high vibration peaks appeared intermittently on both compressor’s drive end (DE) & turbine’s non-drive end (NDE) bearing. The amplitude of high vibration peaks was between 150-170% on the DE bearing & 200-300% on the NDE bearing from baseline values. In one of these episodes, the gas turbine got tripped on “High Vibrations Trip” logic actuated at 155µm. Limited instrumentation is available on the machine, which is monitored with GE Bently Nevada 3300 system having two proximity probes installed at Turbine NDE, Compressor DE &at Generator DE & NDE bearings. Machine’s transient ramp-up & steady state data was collected using ADRE SXP & DSPI 408. Since only 01 key phasor is installed at Turbine high speed shaft, a derived drive key phasor was configured in ADRE to obtain low speed shaft rpm required for data analysis. By analyzing the Bode plots, Shaft center line plot, Polar plot & orbit plots; rubbing was evident on Turbine’s NDE along with increased bearing clearance of Turbine’s NDE radial bearing. The subject bearing was then inspected & heavy deposition of carbonized coke was found on the labyrinth seals of bearing housing with clear rubbing marks on shaft & housing covering at 20-25 degrees on the inner radius of labyrinth seals. The collected coke sample was tested in laboratory & found to be the residue of lube oil in the bearing housing. After detailed inspection & cleaning of shaft journal area & bearing housing, new radial bearing was installed. Before assembling the bearing housing, cleaning of bearing cooling & sealing air lines was also carried out as inadequate flow of cooling & sealing air can accelerate coke formation in bearing housing. The machine was then taken back online & data was collected again using ADRE SXP & DSPI 408 for health analysis. The vibrations were found in acceptable zone as per ISO standard 7919-3 while all other parameters were also within vendor defined range. As a learning from subject case, revised operating & maintenance regime has also been proposed to enhance machine’s reliability.

Keywords: ADRE, bearing, gas turbine, GE Bently Nevada, Hitachi, vibration

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283 Gender Specific Differences in Clinical Outcomes of Knee Osteoarthritis Treated with Micro-Fragmented Adipose Tissue

Authors: Tiffanie-Marie Borg, Yasmin Zeinolabediny, Nima Heidari, Ali Noorani, Mark Slevin, Angel Cullen, Stefano Olgiati, Alberto Zerbi, Alessandro Danovi, Adrian Wilson

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Knee Osteoarthritis (OA) is a critical cause of disability globally. In recent years, there has been growing interest in non-invasive treatments, such as intra-articular injection of micro-fragmented fat (MFAT), showing great potential in treating OA. Mesenchymal stem cells (MSCs), originating from pericytes of micro-vessels in MFAT, can differentiate into mesenchymal lineage cells such as cartilage, osteocytes, adipocytes, and osteoblasts. Secretion of growth factor and cytokines from MSCs have the capability to inhibit T cell growth, reduced pain and inflammation, and create a micro-environment that through paracrine signaling, can promote joint repair and cartilage regeneration. Here we have shown, for the first time, data supporting the hypothesis that women respond better in terms of improvements in pain and function to MFAT injection compared to men. Historically, women have been underrepresented in studies, and studies with both sexes regularly fail to analyse the results by sex. To mitigate this bias and quantify it, we describe a technique using reproducible statistical analysis and replicable results with Open Access statistical software R to calculate the magnitude of this difference. Genetic, hormonal, environmental, and age factors play a role in our observed difference between the sexes. This observational, intention-to-treat study included the complete sample of 456 patients who agreed to be scored for pain (visual analogue scale (VAS)) and function (Oxford knee score (OKS)) at baseline regardless of subsequent changes to adherence or status during follow-up. We report that a significantly larger number of women responded to treatment than men: [90% vs. 60% change in VAS scores with 87% vs. 65% change in OKS scores, respectively]. Women overall had a stronger positive response to treatment with reduced pain and improved mobility and function. Pre-injection, our cohort of women were in more pain with worse joint function which is quite common to see in orthopaedics. However, during the 2-year follow-up, they consistently maintained a lower incidence of discomfort with superior joint function. This data clearly identifies a clear need for further studies to identify the cell and molecular biological and other basis for these differences and be able to utilize this information for stratification in order to improve outcome for both women and men.

Keywords: gender differences, micro-fragmented adipose tissue, knee osteoarthritis, stem cells

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282 Modification of Unsaturated Fatty Acids Derived from Tall Oil Using Micro/Mesoporous Materials Based on H-ZSM-22 Zeolite

Authors: Xinyu Wei, Mingming Peng, Kenji Kamiya, Eika Qian

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Iso-stearic acid as a saturated fatty acid with a branched chain shows a low pour point, high oxidative stability and great biodegradability. The industrial production of iso-stearic acid involves first isomerizing unsaturated fatty acids into branched-chain unsaturated fatty acids (BUFAs), followed by hydrogenating the branched-chain unsaturated fatty acids to obtain iso-stearic acid. However, the production yield of iso-stearic acid is reportedly less than 30%. In recent decades, extensive research has been conducted on branched fatty acids. Most research has replaced acidic clays with zeolites due to their high selectivity, good thermal stability, and renewability. It was reported that isomerization of unsaturated fatty acid occurred mainly inside the zeolite channel. In contrast, the production of by-products like dimer acid mainly occurs at acid sites outside the surface of zeolite. Further, the deactivation of catalysts is attributed to the pore blockage of zeolite. In the present study, micro/mesoporous ZSM-22 zeolites were developed. It is clear that the synthesis of a micro/mesoporous ZSM-22 zeolite is regarded as the ideal strategy owing to its ability to minimize coke formation. Different mesoporosities micro/mesoporous H-ZSM-22 zeolites were prepared through recrystallization of ZSM-22 using sodium hydroxide solution (0.2-1M) with cetyltrimethylammonium bromide template (CTAB). The structure, morphology, porosity, acidity, and isomerization performance of the prepared catalysts were characterized and evaluated. The dissolution and recrystallization process of the H-ZSM-22 microporous zeolite led to the formation of approximately 4 nm-sized mesoporous channels on the outer surface of the microporous zeolite, resulting in a micro/mesoporous material. This process increased the weak Brønsted acid sites at the pore mouth while reducing the total number of acid sites in ZSM-22. Finally, an activity test was conducted using oleic acid as a model compound in a fixed-bed reactor. The activity test results revealed that micro/mesoporous H-ZSM-22 zeolites exhibited a high isomerization activity, reaching >70% selectivity and >50% yield of BUFAs. Furthermore, the yield of oligomers was limited to less than 20%. This demonstrates that the presence of mesopores in ZSM-22 enhances contact between the feedstock and the active sites within the catalyst, thereby increasing catalyst activity. Additionally, a portion of the dissolved and recrystallized silica adhered to the catalyst's surface, covering the surface-active sites, which reduced the formation of oligomers. This study offers distinct insights into the production of iso-stearic acid using a fixed-bed reactor, paving the way for future research in this area.

Keywords: Iso-stearic acid, oleic acid, skeletal isomerization, micro/mesoporous, ZSM-22

Procedia PDF Downloads 23
281 The Impact of Emotional Intelligence on Organizational Performance

Authors: El Ghazi Safae, Cherkaoui Mounia

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Within companies, emotions have been forgotten as key elements of successful management systems. Seen as factors which disturb judgment, make reckless acts or affect negatively decision-making. Since management systems were influenced by the Taylorist worker image, that made the work regular and plain, and considered employees as executing machines. However, recently, in globalized economy characterized by a variety of uncertainties, emotions are proved as useful elements, even necessary, to attend high-level management. The work of Elton Mayo and Kurt Lewin reveals the importance of emotions. Since then emotions start to attract considerable attention. These studies have shown that emotions influence, directly or indirectly, many organization processes. For example, the quality of interpersonal relationships, job satisfaction, absenteeism, stress, leadership, performance and team commitment. Emotions became fundamental and indispensable to individual yield and so on to management efficiency. The idea that a person potential is associated to Intellectual Intelligence, measured by the IQ as the main factor of social, professional and even sentimental success, was the main problematic that need to be questioned. The literature on emotional intelligence has made clear that success at work does not only depend on intellectual intelligence but also other factors. Several researches investigating emotional intelligence impact on performance showed that emotionally intelligent managers perform more, attain remarkable results, able to achieve organizational objectives, impact the mood of their subordinates and create a friendly work environment. An improvement in the emotional intelligence of managers is therefore linked to the professional development of the organization and not only to the personal development of the manager. In this context, it would be interesting to question the importance of emotional intelligence. Does it impact organizational performance? What is the importance of emotional intelligence and how it impacts organizational performance? The literature highlighted that measurement and conceptualization of emotional intelligence are difficult to define. Efforts to measure emotional intelligence have identified three models that are more prominent: the mixed model, the ability model, and the trait model. The first is considered as cognitive skill, the second relates to the mixing of emotional skills with personality-related aspects and the latter is intertwined with personality traits. But, despite strong claims about the importance of emotional intelligence in the workplace, few studies have empirically examined the impact of emotional intelligence on organizational performance, because even though the concept of performance is at the heart of all evaluation processes of companies and organizations, we observe that performance remains a multidimensional concept and many authors insist about the vagueness that surrounds the concept. Given the above, this article provides an overview of the researches related to emotional intelligence, particularly focusing on studies that investigated the impact of emotional intelligence on organizational performance to contribute to the emotional intelligence literature and highlight its importance and show how it impacts companies’ performance.

Keywords: emotions, performance, intelligence, firms

Procedia PDF Downloads 108
280 Quantum Mechanics as A Limiting Case of Relativistic Mechanics

Authors: Ahmad Almajid

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The idea of unifying quantum mechanics with general relativity is still a dream for many researchers, as physics has only two paths, no more. Einstein's path, which is mainly based on particle mechanics, and the path of Paul Dirac and others, which is based on wave mechanics, the incompatibility of the two approaches is due to the radical difference in the initial assumptions and the mathematical nature of each approach. Logical thinking in modern physics leads us to two problems: - In quantum mechanics, despite its success, the problem of measurement and the problem of wave function interpretation is still obscure. - In special relativity, despite the success of the equivalence of rest-mass and energy, but at the speed of light, the fact that the energy becomes infinite is contrary to logic because the speed of light is not infinite, and the mass of the particle is not infinite too. These contradictions arise from the overlap of relativistic and quantum mechanics in the neighborhood of the speed of light, and in order to solve these problems, one must understand well how to move from relativistic mechanics to quantum mechanics, or rather, to unify them in a way different from Dirac's method, in order to go along with God or Nature, since, as Einstein said, "God doesn't play dice." From De Broglie's hypothesis about wave-particle duality, Léon Brillouin's definition of the new proper time was deduced, and thus the quantum Lorentz factor was obtained. Finally, using the Euler-Lagrange equation, we come up with new equations in quantum mechanics. In this paper, the two problems in modern physics mentioned above are solved; it can be said that this new approach to quantum mechanics will enable us to unify it with general relativity quite simply. If the experiments prove the validity of the results of this research, we will be able in the future to transport the matter at speed close to the speed of light. Finally, this research yielded three important results: 1- Lorentz quantum factor. 2- Planck energy is a limited case of Einstein energy. 3- Real quantum mechanics, in which new equations for quantum mechanics match and exceed Dirac's equations, these equations have been reached in a completely different way from Dirac's method. These equations show that quantum mechanics is a limited case of relativistic mechanics. At the Solvay Conference in 1927, the debate about quantum mechanics between Bohr, Einstein, and others reached its climax, while Bohr suggested that if particles are not observed, they are in a probabilistic state, then Einstein said his famous claim ("God does not play dice"). Thus, Einstein was right, especially when he didn't accept the principle of indeterminacy in quantum theory, although experiments support quantum mechanics. However, the results of our research indicate that God really does not play dice; when the electron disappears, it turns into amicable particles or an elastic medium, according to the above obvious equations. Likewise, Bohr was right also, when he indicated that there must be a science like quantum mechanics to monitor and study the motion of subatomic particles, but the picture in front of him was blurry and not clear, so he resorted to the probabilistic interpretation.

Keywords: lorentz quantum factor, new, planck’s energy as a limiting case of einstein’s energy, real quantum mechanics, new equations for quantum mechanics

Procedia PDF Downloads 78
279 Efficiency of Different Types of Addition onto the Hydration Kinetics of Portland Cement

Authors: Marine Regnier, Pascal Bost, Matthieu Horgnies

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Some of the problems to be solved for the concrete industry are linked to the use of low-reactivity cement, the hardening of concrete under cold-weather and the manufacture of pre-casted concrete without costly heating step. The development of these applications needs to accelerate the hydration kinetics, in order to decrease the setting time and to obtain significant compressive strengths as soon as possible. The mechanisms enhancing the hydration kinetics of alite or Portland cement (e.g. the creation of nucleation sites) were already studied in literature (e.g. by using distinct additions such as titanium dioxide nanoparticles, calcium carbonate fillers, water-soluble polymers, C-S-H, etc.). However, the goal of this study was to establish a clear ranking of the efficiency of several types of additions by using a robust and reproducible methodology based on isothermal calorimetry (performed at 20°C). The cement was a CEM I 52.5N PM-ES (Blaine fineness of 455 m²/kg). To ensure the reproducibility of the experiments and avoid any decrease of the reactivity before use, the cement was stored in waterproof and sealed bags to avoid any contact with moisture and carbon dioxide. The experiments were performed on Portland cement pastes by using a water-to-cement ratio of 0.45, and incorporating different compounds (industrially available or laboratory-synthesized) that were selected according to their main composition and their specific surface area (SSA, calculated using the Brunauer-Emmett-Teller (BET) model and nitrogen adsorption isotherms performed at 77K). The intrinsic effects of (i) dry powders (e.g. fumed silica, activated charcoal, nano-precipitates of calcium carbonate, afwillite germs, nanoparticles of iron and iron oxides , etc.), and (ii) aqueous solutions (e.g. containing calcium chloride, hydrated Portland cement or Master X-SEED 100, etc.) were investigated. The influence of the amount of addition, calculated relatively to the dry extract of each addition compared to cement (and by conserving the same water-to-cement ratio) was also studied. The results demonstrated that the X-SEED®, the hydrated calcium nitrate, the calcium chloride (and, at a minor level, a solution of hydrated Portland cement) were able to accelerate the hydration kinetics of Portland cement, even at low concentration (e.g. 1%wt. of dry extract compared to cement). By using higher rates of additions, the fumed silica, the precipitated calcium carbonate and the titanium dioxide can also accelerate the hydration. In the case of the nano-precipitates of calcium carbonate, a correlation was established between the SSA and the accelerating effect. On the contrary, the nanoparticles of iron or iron oxides, the activated charcoal and the dried crystallised hydrates did not show any accelerating effect. Future experiments will be scheduled to establish the ranking of these additions, in terms of accelerating effect, by using low-reactivity cements and other water to cement ratios.

Keywords: acceleration, hydration kinetics, isothermal calorimetry, Portland cement

Procedia PDF Downloads 257
278 Temperature Contour Detection of Salt Ice Using Color Thermal Image Segmentation Method

Authors: Azam Fazelpour, Saeed Reza Dehghani, Vlastimil Masek, Yuri S. Muzychka

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The study uses a novel image analysis based on thermal imaging to detect temperature contours created on salt ice surface during transient phenomena. Thermal cameras detect objects by using their emissivities and IR radiance. The ice surface temperature is not uniform during transient processes. The temperature starts to increase from the boundary of ice towards the center of that. Thermal cameras are able to report temperature changes on the ice surface at every individual moment. Various contours, which show different temperature areas, appear on the ice surface picture captured by a thermal camera. Identifying the exact boundary of these contours is valuable to facilitate ice surface temperature analysis. Image processing techniques are used to extract each contour area precisely. In this study, several pictures are recorded while the temperature is increasing throughout the ice surface. Some pictures are selected to be processed by a specific time interval. An image segmentation method is applied to images to determine the contour areas. Color thermal images are used to exploit the main information. Red, green and blue elements of color images are investigated to find the best contour boundaries. The algorithms of image enhancement and noise removal are applied to images to obtain a high contrast and clear image. A novel edge detection algorithm based on differences in the color of the pixels is established to determine contour boundaries. In this method, the edges of the contours are obtained according to properties of red, blue and green image elements. The color image elements are assessed considering their information. Useful elements proceed to process and useless elements are removed from the process to reduce the consuming time. Neighbor pixels with close intensities are assigned in one contour and differences in intensities determine boundaries. The results are then verified by conducting experimental tests. An experimental setup is performed using ice samples and a thermal camera. To observe the created ice contour by the thermal camera, the samples, which are initially at -20° C, are contacted with a warmer surface. Pictures are captured for 20 seconds. The method is applied to five images ,which are captured at the time intervals of 5 seconds. The study shows the green image element carries no useful information; therefore, the boundary detection method is applied on red and blue image elements. In this case study, the results indicate that proposed algorithm shows the boundaries more effective than other edges detection methods such as Sobel and Canny. Comparison between the contour detection in this method and temperature analysis, which states real boundaries, shows a good agreement. This color image edge detection method is applicable to other similar cases according to their image properties.

Keywords: color image processing, edge detection, ice contour boundary, salt ice, thermal image

Procedia PDF Downloads 314
277 Direct Current Grids in Urban Planning for More Sustainable Urban Energy and Mobility

Authors: B. Casper

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The energy transition towards renewable energies and drastically reduced carbon dioxide emissions in Germany drives multiple sectors into a transformation process. Photovoltaic and on-shore wind power are predominantly feeding in the low and medium-voltage grids. The electricity grid is not laid out to allow an increasing feed-in of power in low and medium voltage grids. Electric mobility is currently in the run-up phase in Germany and still lacks a significant amount of charging stations. The additional power demand by e-mobility cannot be supplied by the existing electric grids in most cases. The future demands in heating and cooling of commercial and residential buildings are increasingly generated by heat-pumps. Yet the most important part in the energy transition is the storage of surplus energy generated by photovoltaic and wind power sources. Water electrolysis is one way to store surplus energy known as power-to-gas. With the vehicle-to-grid technology, the upcoming fleet of electric cars could be used as energy storage to stabilize the grid. All these processes use direct current (DC). The demand of bi-directional flow and higher efficiency in the future grids can be met by using DC. The Flexible Electrical Networks (FEN) research campus at RWTH Aachen investigates interdisciplinary about the advantages, opportunities, and limitations of DC grids. This paper investigates the impact of DC grids as a technological innovation on the urban form and urban life. Applying explorative scenario development, analyzation of mapped open data sources on grid networks and research-by-design as a conceptual design method, possible starting points for a transformation to DC medium voltage grids could be found. Several fields of action have emerged in which DC technology could become a catalyst for future urban development: energy transition in urban areas, e-mobility, and transformation of the network infrastructure. The investigation shows a significant potential to increase renewable energy production within cities with DC grids. The charging infrastructure for electric vehicles will predominantly be using DC in the future because fast and ultra fast charging can only be achieved with DC. Our research shows that e-mobility, combined with autonomous driving has the potential to change the urban space and urban logistics fundamentally. Furthermore, there are possible win-win-win solutions for the municipality, the grid operator and the inhabitants: replacing overhead transmission lines by underground DC cables to open up spaces in contested urban areas can lead to a positive example of how the energy transition can contribute to a more sustainable urban structure. The outlook makes clear that target grid planning and urban planning will increasingly need to be synchronized.

Keywords: direct current, e-mobility, energy transition, grid planning, renewable energy, urban planning

Procedia PDF Downloads 128
276 Public Participation in Political Transformation: From the Coup D’etat in 2014 to the Events Leading up to the Proposed Election in 2018 in Thailand

Authors: Pataramon Satalak, Sakrit Isariyanon, Teerapong Puripanik

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This article uses the recent events in Thailand as a case study for examining why democratic transition is necessary during political upheaval to ensure that the people’s power remains unaffected. After seizing power in May 2014, the military, backed by anti-government protestors, selected and established their own system to govern the country. They set up the National Council for Peace and Order (NCPO) which established a People’s Assembly, aiming to reach a compromise between the conflicting opinions of former, pro-government and anti-government protesters. It plans to achieve this through political reform before returning sovereign power to the people via an election in 2018. If a governmental authority is not representative of the people (e.g. a military government) it does not count as a legitimate government. During the last four years of military government, from May 2014 to January 2018, their rule of Thailand has been widely controversial, specifically regarding their commitment to democracy, human rights violations and their manipulation of the rule of law. Democratic legitimacy relies not only on established mechanisms for public participation (like referendums or elections) but also public participation based on accessible and educational reform (often via NGOs) to ensure that the free and fair will of the people can be expressed. Through their actions over the last three years, the Thai military government has damaged both of these components, impacting future public participation in politics. The authors make some observations about the specific actions the military government has taken to erode the democratic legitimacy of future public participation: the increasing dominance of military courts over civil courts; civil society’s limited involvement in political activities; the drafting of a new constitution and their attempt to master support through referenda and its consequence for delaying organic law-making process; the structure of the legislative powers (Senate and the members of parliament); and the control of people’s basic freedoms of expression, movement and assembly in political activities. One clear consequence of the military government’s specific actions over the last three years is the increased uncertainty amongst Thai people that their fundamental freedoms and political rights will be respected in the future. This will directly affect their participation in future democratic processes. The military government’s actions (e.g. their response to the UN representatives) will also have influenced potential international engagement in Thai civil society to help educate disadvantaged people about their rights, and their participation in the political arena. These actions challenge the democratic idea that there should be a checking and balancing of power between people and government. These examples provide evidence that a democratic transition is crucial during any process of political transformation.

Keywords: political tranformation, public participation, Thailand coup d'etat 2014, election 2018

Procedia PDF Downloads 148
275 Investigation of Cavitation in a Centrifugal Pump Using Synchronized Pump Head Measurements, Vibration Measurements and High-Speed Image Recording

Authors: Simon Caba, Raja Abou Ackl, Svend Rasmussen, Nicholas E. Pedersen

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It is a challenge to directly monitor cavitation in a pump application during operation because of a lack of visual access to validate the presence of cavitation and its form of appearance. In this work, experimental investigations are carried out in an inline single-stage centrifugal pump with optical access. Hence, it gives the opportunity to enhance the value of CFD tools and standard cavitation measurements. Experiments are conducted using two impellers running in the same volute at 3000 rpm and the same flow rate. One of the impellers used is optimized for lower NPSH₃% by its blade design, whereas the other one is manufactured using a standard casting method. The cavitation is detected by pump performance measurements, vibration measurements and high-speed image recordings. The head drop and the pump casing vibration caused by cavitation are correlated with the visual appearance of the cavitation. The vibration data is recorded in an axial direction of the impeller using accelerometers recording at a sample rate of 131 kHz. The vibration frequency domain data (up to 20 kHz) and the time domain data are analyzed as well as the root mean square values. The high-speed recordings, focusing on the impeller suction side, are taken at 10,240 fps to provide insight into the flow patterns and the cavitation behavior in the rotating impeller. The videos are synchronized with the vibration time signals by a trigger signal. A clear correlation between cloud collapses and abrupt peaks in the vibration signal can be observed. The vibration peaks clearly indicate cavitation, especially at higher NPSHA values where the hydraulic performance is not affected. It is also observed that below a certain NPSHA value, the cavitation started in the inlet bend of the pump. Above this value, cavitation occurs exclusively on the impeller blades. The impeller optimized for NPSH₃% does show a lower NPSH₃% than the standard impeller, but the head drop starts at a higher NPSHA value and is more gradual. Instabilities in the head drop curve of the optimized impeller were observed in addition to a higher vibration level. Furthermore, the cavitation clouds on the suction side appear more unsteady when using the optimized impeller. The shape and location of the cavitation are compared to 3D fluid flow simulations. The simulation results are in good agreement with the experimental investigations. In conclusion, these investigations attempt to give a more holistic view on the appearance of cavitation by comparing the head drop, vibration spectral data, vibration time signals, image recordings and simulation results. Data indicates that a criterion for cavitation detection could be derived from the vibration time-domain measurements, which requires further investigation. Usually, spectral data is used to analyze cavitation, but these investigations indicate that the time domain could be more appropriate for some applications.

Keywords: cavitation, centrifugal pump, head drop, high-speed image recordings, pump vibration

Procedia PDF Downloads 180
274 Validation of Global Ratings in Clinical Performance Assessment

Authors: S. J. Yune, S. Y. Lee, S. J. Im, B. S. Kam, S. Y. Baek

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This study aimed to determine the reliability of clinical performance assessments, having been emphasized by ability-based education, and professors overall assessment methods. We addressed the following problems: First, we try to find out whether there is a difference in what we consider to be the main variables affecting the clinical performance test according to the evaluator’s working period and the number of evaluation experience. Second, we examined the relationship among the global rating score (G), analytic global rating score (Gc), and the sum of the analytical checklists (C). What are the main factors affecting clinical performance assessments in relation to the numbers of times the evaluator had administered evaluations and the length of their working period service? What is the relationship between overall assessment score and analytic checklist score? How does analytic global rating with 6 components in OSCE and 4 components in sub-domains (Gc) CPX: aseptic practice, precision, systemic approach, proficiency, successfulness, and attitude overall assessment score and task-specific analytic checklist score sum (C) affect the professor’s overall global rating assessment score (G)? We studied 75 professors who attended a 2016 Bugyeoung Consortium clinical skills performances test evaluating third and fourth year medical students at the Pusan National University Medical school in South Korea (39 prof. in OSCE, 36 prof. in CPX; all consented to participate in our study). Each evaluator used 3 forms; a task-specific analytic checklist, subsequent analytic global rating scale with sub-6 domains, and overall global scale. After the evaluation, the professors responded to the questionnaire on the important factors of clinical performance assessment. The data were analyzed by frequency analysis, correlation analysis, and hierarchical regression analysis using SPSS 21.0. Their understanding of overall assessment was analyzed by dividing the subjects into groups based on experiences. As a result, they considered ‘precision’ most important in overall OSCE assessment, and ‘precise accuracy physical examination’, ‘systemic approaches to taking patient history’, and ‘diagnostic skill capability’ in overall CPX assessment. For OSCE, there was no clear difference of opinion about the main factors, but there was for CPX. Analytic global rating scale score, overall rating scale score, and analytic checklist score had meaningful mutual correlations. According to the regression analysis results, task-specific checklist score sum had the greatest effect on overall global rating. professors regarded task-specific analytic checklist total score sum as best reflecting overall OSCE test score, followed by aseptic practice, precision, systemic approach, proficiency, successfulness, and attitude on a subsequent analytic global rating scale. For CPX, subsequent analytic global rating scale score, overall global rating scale score, and task-specific checklist score had meaningful mutual correlations. These findings support explanations for validity of professors’ global rating in clinical performance assessment.

Keywords: global rating, clinical performance assessment, medical education, analytic checklist

Procedia PDF Downloads 235
273 Evaluation of River Meander Geometry Using Uniform Excess Energy Theory and Effects of Climate Change on River Meandering

Authors: Youssef I. Hafez

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Since ancient history rivers have been the fostering and favorite place for people and civilizations to live and exist along river banks. However, due to floods and droughts, especially sever conditions due to global warming and climate change, river channels are completely evolving and moving in the lateral direction changing their plan form either through straightening of curved reaches (meander cut-off) or increasing meandering curvature. The lateral shift or shrink of a river channel affects severely the river banks and the flood plain with tremendous impact on the surrounding environment. Therefore, understanding the formation and the continual processes of river channel meandering is of paramount importance. So far, in spite of the huge number of publications about river-meandering, there has not been a satisfactory theory or approach that provides a clear explanation of the formation of river meanders and the mechanics of their associated geometries. In particular two parameters are often needed to describe meander geometry. The first one is a scale parameter such as the meander arc length. The second is a shape parameter such as the maximum angle a meander path makes with the channel mean down path direction. These two parameters, if known, can determine the meander path and geometry as for example when they are incorporated in the well known sine-generated curve. In this study, a uniform excess energy theory is used to illustrate the origin and mechanics of formation of river meandering. This theory advocates that the longitudinal imbalance between the valley and channel slopes (with the former is greater than the second) leads to formation of curved meander channel in order to reduce the excess energy through its expenditure as transverse energy loss. Two relations are developed based on this theory; one for the determination of river channel radius of curvature at the bend apex (shape parameter) and the other for the determination of river channel sinuosity. The sinuosity equation tested very well when applied to existing available field data. In addition, existing model data were used to develop a relation between the meander arc length and the Darcy-Weisback friction factor. Then, the meander wave length was determined from the equations of the arc length and the sinuosity. The developed equation compared well with available field data. Effects of the transverse bed slope and grain size on river channel sinuosity are addressed. In addition, the concept of maximum channel sinuosity is introduced in order to explain the changes of river channel plan form due to changes in flow discharges and sediment loads induced by global warming and climate changes.

Keywords: river channel meandering, sinuosity, radius of curvature, meander arc length, uniform excess energy theory, transverse energy loss, transverse bed slope, flow discharges, sediment loads, grain size, climate change, global warming

Procedia PDF Downloads 223
272 Polarimetric Study of System Gelatin / Carboxymethylcellulose in the Food Field

Authors: Sihem Bazid, Meriem El Kolli, Aicha Medjahed

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Proteins and polysaccharides are the two types of biopolymers most frequently used in the food industry to control the mechanical properties and structural stability and organoleptic properties of the products. The textural and structural properties of these two types of blend polymers depend on their interaction and their ability to form organized structures. From an industrial point of view, a better understanding of mixtures protein / polysaccharide is an important issue since they are already heavily involved in processed food. It is in this context that we have chosen to work on a model system composed of a fibrous protein mixture (gelatin)/anionic polysaccharide (sodium carboxymethylcellulose). Gelatin, one of the most popular biopolymers, is widely used in food, pharmaceutical, cosmetic and photographic applications, because of its unique functional and technological properties. Sodium Carboxymethylcellulose (NaCMC) is an anionic linear polysaccharide derived from cellulose. It is an important industrial polymer with a wide range of applications. The functional properties of this anionic polysaccharide can be modified by the presence of proteins with which it might interact. Another factor may also manage the interaction of protein-polysaccharide mixtures is the triple helix of the gelatin. Its complex synthesis method results in an extracellular assembly containing several levels. Collagen can be in a soluble state or associate into fibrils, which can associate in fiber. Each level corresponds to an organization recognized by the cellular and metabolic system. Gelatin allows this approach, the formation of gelatin gel has triple helical folding of denatured collagen chains, this gel has been the subject of numerous studies, and it is now known that the properties depend only on the rate of triple helices forming the network. Chemical modification of this system is quite controlled. Observe the dynamics of the triple helix may be relevant in understanding the interactions involved in protein-polysaccharides mixtures. Gelatin is central to any industrial process, understand and analyze the molecular dynamics induced by the triple helix in the transitions gelatin, can have great economic importance in all fields and especially the food. The goal is to understand the possible mechanisms involved depending on the nature of the mixtures obtained. From a fundamental point of view, it is clear that the protective effect of NaCMC on gelatin and conformational changes of the α helix are strongly influenced by the nature of the medium. Our goal is to minimize the maximum the α helix structure changes to maintain more stable gelatin and protect against denaturation that occurs during such conversion processes in the food industry. In order to study the nature of interactions and assess the properties of mixtures, polarimetry was used to monitor the optical parameters and to assess the rate of helicity gelatin.

Keywords: gelatin, sodium carboxymethylcellulose, interaction gelatin-NaCMC, the rate of helicity, polarimetry

Procedia PDF Downloads 313
271 A Study of the Challenges in Adoption of Renewable Energy in Nigeria

Authors: Farouq Sule Garo, Yahaya Yusuf

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The purpose of this study is to investigate why there is a general lack of successful adoption of sustainable energy in Nigeria. This is particularly important given the current global campaign for net-zero emissions. The 26th United Nations Conference of the Parties (COP26), held in 2021, was hosted by the UK, in Glasgow, where, amongst other things, countries including Nigeria agreed to a zero emissions pact. There is, therefore, an obligation on the part of Nigeria for transition from fossil fuel-based economy to a sustainable net-zero emissions economy. The adoption of renewable energy is fundamental to achieving this ambitious target if decarbonisation of economic activities were to become a reality. Nigeria has an abundance of sources of renewable energy and yet there has been poor uptake and where attempts have been made to develop and harness renewable energy resources, there has been limited success. It is not entirely clear why this is the case. When analysts allude to corruption as the reason for failure for successful adoption of renewable energy or project implementation, it is arguable that corruption alone cannot explain the situation. Therefore, there is the need for a thorough investigation into the underlying issues surrounding poor uptake of renewable energy in Nigeria. This pilot study, drawing upon stakeholders’ theory, adopts a multi-stakeholder’ perspectives to investigate the influence and impacts of economic, political, technological, social factors in adoption of renewable energy in Nigeria. The research will also investigate how these factors shape (or fail to shape) strategies for achieving successful adoption of renewable energy in the country. A qualitative research methodology has been adopted given the nature of the research requiring in-depth studies in specific settings rather than a general population survey. There will be a number of interviews and each interview will allow thorough probing of sources. This, in addition to the six interviews that have already been conducted, primarily focused on economic dimensions of the challenges in adoption of renewable energy. The six participants in these initial interviews were all connected to the Katsina Wind Farm Project that was conceived and built with the view to diversifying Nigeria's energy mix and capitalise on the vast wind energy resources in the northern region. The findings from the six interviews provide insights into how the economic factors impacts on the wind farm project. Some key drivers have been identified, including strong governmental support and the recognition of the need for energy diversification. These drivers have played crucial roles in initiating and advancing the Katsina Wind Farm Project. In addition, the initial analysis has highlighted various challenges encountered during the project's implementation, including financial, regulatory, and environmental aspects. These challenges provide valuable lessons that can inform strategies to mitigate risks and improve future wind energy projects.

Keywords: challenges in adoption of renewable energy, economic factors, net-zero emission, political factors

Procedia PDF Downloads 40
270 Variation of Lexical Choice and Changing Need of Identity Expression

Authors: Thapasya J., Rajesh Kumar

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Language plays complex roles in society. The previous studies on language and society explain their interconnected, complementary and complex interactions and, those studies were primarily focused on the variations in the language. Variation being the fundamental nature of languages, the question of personal and social identity navigated through language variation and established that there is an interconnection between language variation and identity. This paper analyses the sociolinguistic variation in language at the lexical level and how the lexical choice of the speaker(s) affects in shaping their identity. It obtains primary data from the lexicon of the Mappila dialect of Malayalam spoken by the members of Mappila (Muslim) community of Kerala. The variation in the lexical choice is analysed by collecting data from the speech samples of 15 minutes from four different age groups of Mappila dialect speakers. Various contexts were analysed and the frequency of borrowed words in each instance is calculated to reach a conclusion on how the variation is happening in the speech community. The paper shows how the lexical choice of the speakers could be socially motivated and involve in shaping and changing identities. Lexical items or vocabulary clearly signal the group identity and personal identity. Mappila dialect of Malayalam was rich in frequent use of borrowed words from Arabic, Persian and Urdu. There was a deliberate attempt to show their identity as a Mappila community member, which was derived from the socio-political situation during those days. This made a clear variation between the Mappila dialect and other dialects of Malayalam at the surface level, which was motivated to create and establish the identity of a person as the member of Mappila community. Historically, these kinds of linguistic variation were highly motivated because of the socio-political factors and, intertwined with the historical facts about the origin and spread of Islamism in the region; people from the Mappila community highly motivated to project their identity as a Mappila because of the social insecurities they had to face before accepting that religion. Thus the deliberate inclusion of Arabic, Persian and Urdu words in their speech helped in showing their identity. However, the socio-political situations and factors at the origin of Mappila community have been changed over a period of time. The social motivation for indicating their identity as a Mappila no longer exist and thus the frequency of borrowed words from Arabic, Persian and Urdu have been reduced from their speech. Apart from the religious terms, the borrowed words from these languages are very few at present. The analysis is carried out by the changes in the language of the people according to their age and found to have significant variations between generations and literacy plays a major role in this variation process. The need of projecting a specific identity of an individual would vary according to the change in the socio-political scenario and a variation in language can shape the identity in order to go with the varying socio-political situation in any language.

Keywords: borrowings, dialect, identity, lexical choice, literacy, variation

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269 Exploring the Social Health and Well-Being Factors of Hydraulic Fracturing

Authors: S. Grinnell

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A PhD Research Project exploring the Social Health and Well-Being Impacts associated with Hydraulic Fracturing, with an aim to produce a Best Practice Support Guidance for those anticipating dealing with planning applications or submitting Environmental Impact Assessments (EIAs). Amid a possible global energy crisis, founded upon a number of factors, including unstable political situations, increasing world population growth, people living longer, it is perhaps inevitable that Hydraulic Fracturing (commonly referred to as ‘fracking’) will become a major player within the global long-term energy and sustainability agenda. As there is currently no best practice guidance for governing bodies the Best Practice Support Document will be targeted at a number of audiences including, consultants undertaking EIAs, Planning Officers, those commissioning EIAs Industry and interested public stakeholders. It will offer a robust, evidence-based criteria and recommendations which provide a clear narrative and consistent and shared approach to the language used along with containing an understanding of the issues identified. It is proposed that the Best Practice Support Document will also support the mitigation of health impacts identified. The Best Practice Support Document will support the newly amended Environmental Impact Assessment Directive (2011/92/EU), to be transposed into UK law by 2017. A significant amendment introduced focuses on, ‘higher level of protection to the environment and health.’ Methodology: A qualitative research methods approach is being taken with this research. It will have a number of key stages. A literature review has been undertaken and been critically reviewed and analysed. This was followed by a descriptive content analysis of a selection of international and national policies, programmes and strategies along with published Environmental Impact Assessments and associated planning guidance. In terms of data collection, a number of stakeholders were interviewed as well as a number of focus groups of local community groups potentially affected by fracking. These were determined from across the UK. A theme analysis of all the data collected and the literature review will be undertaken, using NVivo. Best Practice Supporting Document will be developed based on the outcomes of the analysis and be tested and piloted in the professional fields, before a live launch. Concluding statement: Whilst fracking is not a new concept, the technology is now driving a new force behind the use of this engineering to supply fuels. A number of countries have pledged moratoria on fracking until further investigation from the impacts on health have been explored, whilst other countries including Poland and the UK are pushing to support the use of fracking. If this should be the case, it will be important that the public’s concerns, perceptions, fears and objections regarding the wider social health and well-being impacts are considered along with the more traditional biomedical health impacts.

Keywords: fracking, hydraulic fracturing, socio-economic health, well-being

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268 Effectiveness, Safety, and Tolerability Profile of Stribild® in HIV-1-infected Patients in the Clinical Setting

Authors: Heiko Jessen, Laura Tanus, Slobodan Ruzicic

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Objectives: The efficacy of Stribild®, an integrase strand transfer inhibitor (INSTI) -based STR, has been evaluated in randomized clinical trials and it has demonstrated durable capability in terms of achieving sustained suppression of HIV-1 RNA-levels. However, differences in monitoring frequency, existing selection bias and profile of patients enrolled in the trials, may all result in divergent efficacy of this regimen in routine clinical settings. The aim of this study was to assess the virologic outcomes, safety and tolerability profile of Stribild® in a routine clinical setting. Methods: This was a retrospective monocentric analysis on HIV-1-infected patients, who started with or were switched to Stribild®. Virological failure (VF) was defined as confirmed HIV-RNA>50 copies/ml. The minimum time of follow-up was 24 weeks. The percentage of patients remaining free of therapeutic failure was estimated using the time-to-loss-of-virologic-response (TLOVR) algorithm, by intent-to-treat analysis. Results: We analyzed the data of 197 patients (56 ART-naïve and 141 treatment-experienced patients), who fulfilled the inclusion criteria. Majority (95.9%) of patients were male. The median time of HIV-infection at baseline was 2 months in treatment-naïve and 70 months in treatment-experienced patients. Median time [IQR] under ART in treatment-experienced patients was 37 months. Among the treatment-experienced patients 27.0% had already been treated with a regimen consisting of two NRTIs and one INSTI, whereas 18.4% of them experienced a VF. The median time [IQR] of virological suppression prior to therapy with Stribild® in the treatment-experienced patients was 10 months [0-27]. At the end of follow-up (median 33 months), 87.3% (95% CI, 83.5-91.2) of treatment-naïve and 80.3% (95% CI, 75.8-84.8) of treatment-experienced patients remained free of therapeutic failure. Considering only treatment-experienced patients with baseline VL<50 copies/ml, 83.0% (95% CI, 78.5-87.5) remained free of therapeutic failure. A total of 17 patients stopped treatment with Stribild®, 5.4% (3/56) of them were treatment-naïve and 9.9% (14/141) were treatment-experienced patients. The Stribild® therapy was discontinued in 2 (1.0%) because of VF, loss to follow-up in 4 (2.0%), and drug-drug interactions in 2 (1.0%) patients. Adverse events were in 7 (3.6%) patients the reason to switch from therapy with Stribild® and further 2 (1.0%) patients decided personally to switch. The most frequently observed adverse events were gastrointestinal side effects (20.0%), headache (8%), rash events (7%) and dizziness (6%). In two patients we observed an emergence of novel resistances in integrase-gene. The N155H evolved in one patient and resulted in VF. In another patient S119R evolved either during or shortly upon switch from therapy with Stribild®. In one further patient with VF two novel mutations in the RT-gene were observed when compared to historical genotypic test result (V106I/M and M184V), whereby it is not clear whether they evolved during or already before the switch to Stribild®. Conclusions: Effectiveness of Stribild® for treatment-naïve patients was consistent with data obtained in clinical trials. The safety and tolerability profile as well as resistance development confirmed clinical efficacy of Stribild® in a daily practice setting.

Keywords: ART, HIV, integrase inhibitor, stribild

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267 The Role of the Corporate Social Responsibility in Poverty Reduction

Authors: M. Verde, G. Falzarano

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The paper examines the connection between corporate social responsibility (CSR), capability approach and poverty reduction; in particular, the local employment development (LED) by way of CSR initiatives. The joint action of LED/CSR results in a win-win situation, not only for the enterprises but also for all the stakeholders involved; in this regard, subsidiarity and coordination between national and regional/local authorities are central to a socially-oriented market economy. In the first section, the CSR is analysed on the basis of its social function in the fight against poverty, as a 'capabilities deprivation'. In the central part, the attention is focused on the relationship between CSR and LED; ergo, on the role of the enterprises in fostering capabilities development (the employment). Besides, all the potential solutions are presented, stressing the possible combinations, in the last part. The benchmark is the enterprise as an economic and a social institution: the business should not be combined with profit merely, paying more attention to its sustainable impact and social contribution. In which way could it be possible? The answer is the CSR. The impact of CSR on poverty reduction is still little explored. The companies help to reduce poverty through economic contribution, human rights and social inclusion; hence, the business becomes an 'agent of development' in order to fight against 'inequality'. The starting point is the pyramid of social responsibility, where ethic and philanthropic responsibilities involve programmes and actions aimed at personal development of the individuals, improving human standard of living in all forms, including poverty, when people do not have a choice between different 'life options', ranging from level of education to employment. At this point, CSR comes into play and works on two dimensions: poverty reduction and poverty prevention, by means of a series of initiatives: first of all, job creation and precarious work reduction. Empowerment of the local actors, financial support and combination of top down and bottom up initiatives are some of CSR areas of activity. Several positive effects occur on individual levels of educations, access to capital, individual health status, empowerment of youth and woman, access to social networks and it was observed that these effects depend on the type of CSR strategy. Indeed, CSR programmes should take into account fundamental criteria, such as the transparency, the information about benefits, a coordination unit among institutions and more clear guidelines. In this way, the advantages to the corporate reputation and to the community translate into a better job matching on the labour market, inter alia. It is important to underline that the success depends on the specific measures of the areas in question, by adapting them to the local needs, in light of general principles and index; therefore, the concrete commitment of the all stakeholders involved is decisive in order to achieve the goals. The enterprise would represent a concrete contribution for the pursuit of sustainable development and for the dissemination of a social and well being awareness.

Keywords: capability approach, local employment development, poverty, social inclusion

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266 Midwives’ Perceptions and Experiences of Recommending and Delivering Vaccines to Pregnant Women Following the COVID-19 Pandemic

Authors: Cath Grimley, Debra Bick, Sarah Hillman, Louise Clarke, Helen Atherton, Jo Parsons

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The problem: Women in the UK are offered influenza (flu), pertussis (whooping cough) and COVID-19 vaccinations during their pregnancy but uptake of all three vaccines is below the desired rate. These vaccines are offered during pregnancy as pregnant women are at an increased risk of hospitalisation, morbidity, and mortality from these illnesses. Exposure to these diseases during pregnancy can also have a negative impact on the unborn baby with an increased risk of serious complications both while in utero and following birth. The research aims to explore perceptions about the vaccinations offered in pregnancy both from the perspectives of pregnant women and midwives. To determine factors that influence pregnant women’s decisions about whether or not to accept the vaccines following the Covid-19 pandemic and to explore midwives’ experiences of recommending and delivering vaccines. The approach: This research follows a qualitative design involving semi-structured interviews with pregnant women and midwives in the UK. Interviews with midwives explored vaccination discussions they routinely have with pregnant women and identified some of the barriers to vaccination that pregnant women discuss with them. Interviews with pregnant women explored their views since the COVID-19 pandemic about vaccinations offered during pregnancy, and whether the pandemic has influenced perceptions of vulnerability to illness in pregnant women. Midwives were recruited via participating hospitals and midwife specific social media groups. Pregnant women were recruited via participating hospitals and community groups. All interviews were conducted remotely (using telephone or Microsoft Teams) and analysed using thematic analysis. Findings: 43 pregnant women and 16 midwives were recruited and interviewed. The findings presented here will focus on data from midwives. Topics identified included three key themes for midwives. These were 1) Delivery of vaccinations which includes the convenience of offering vaccinations while attending standard antenatal appointments and practical barriers faced in delivering these vaccinations at hospital. 2) Messages and guidance included the importance of up-to-date informational needs for midwives to deliver vaccines and that uncertainty and conflicting messages about the COVID-19 vaccine during pregnancy were a barrier to delivery. 3) Recommendations to have vaccines look at all aspects of recommendations such as how recommendations are communicated, the contents of the recommendation, the importance of the vaccine and the impact of those recommendations on whether women accept the vaccine. Implications: Findings highlight the importance for midwives to receive clear and consistent information so they can feel confident in relaying this information while recommending and delivering vaccines to pregnant women. Emphasising why vaccines are important when recommending vaccinations to pregnant women in addition to standard information on the availability and timing will add to the strength and impact of that recommendation in helping women to make informed decisions about accepting vaccines. The findings of this study will inform the development of an intervention to increase vaccination uptake amongst pregnant women.

Keywords: vaccination, pregnancy, qualitative, interviews, Covid-19, midwives

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265 Iron Doping Enhanced Photocatalytic Nitrogen Fixation Performance of WO₃ with Three-Dimensionally Orderd Macroporous Structure

Authors: Xiaoling Ren, Guidong Yang

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Ammonia, as one of the largest-volume industrial chemicals, is mostly produced by century-old Haber-Bosch process with extreme conditionsand high-cost. Under the circumstance, researchersarededicated in finding new ways to replace the Haber-Bosch process. Photocatalytic nitrogen fixation is a promising sustainable, clear and green strategy for ammonia synthesis, butit is still a big challenge due to the high activation energy for nitrogen. It is essential to develop an efficient photocatalyst for making this approach industrial application. Constructing chemisorption active sites through defect engineering can be defined as an effective and reliable means to improve nitrogen activation by forming the extraordinary coordination environment and electronic structure. Besides, the construction of three-dimensionally orderdmacroporous (3DOM) structured photocatalyst is considered to be one of effectivestrategiesto improve the activity due to it canincrease the diffusion rate of reactants in the interior, which isbeneficial to the mass transfer process of nitrogen molecules in photocatalytic nitrogen reduction. Herein, Fe doped 3DOM WO₃(Fe-3DOM WO₃) without noble metal cocatalysts is synthesized by a polystyrene-template strategy, which is firstly used for photocatalytic nitrogen fixation. To elucidate the chemical nature of the dopant, the X-ray diffraction (XRD) analysiswas conducted. The pure 3DOM WO₃ has a monoclinic type crystal structure. And no additional peak is observed in Fe doped 3DOM WO₃, indicating that the incorporation of Fe atoms did not result in a secondary phase formation. In order to confirm the morphologies of Fe-3DOM WO₃and 3DOM WO₃, scanning electron microscopy (SEM) was employed. The synthesized Fe-3DOM WO₃and 3DOM WO₃ both exhibit a highly ordered three dimensional inverse opal structure with interconnected pores. From high-resolution TEM image of Fe-3DOM WO₃, the ordered lattice fringes with a spacing of 3.84 Å can be assigned to the (001) plane of WO₃, which is consistent with the XRD results. Finally, the photocatalytic nitrogen reduction performance of 3DOM WO₃ and Fe doped 3DOM WO₃with various Fe contents were examined. As a result, both Fe-3DOM WO₃ samples achieve higher ammonia production rate than that of pure 3DOM WO₃, indicating that the doped Fe plays a critical role in the photocatalytic nitrogen fixation performance. To verify the reaction process upon N2 reduction on the Fe-3DOM WO₃, in-situ diffuse reflectance infrared Fourier-transform spectroscopy was employed to monitor the intermediates. The in-situ DRIFTS spectra of Fe-3DOM WO₃ exhibit the increased signals with the irradiation time from 0–60min in the N2 atmosphere. The above results prove that nitrogen is gradually hydrogenated to produce ammonia over Fe-3DOM WO₃. Thiswork would enrich our knowledge in designing efficient photocatalystsfor photocatalytic nitrogen reduction.

Keywords: ammonia, photocatalytic, nitrogen fixation, Fe doped 3DOM WO₃

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