Search results for: frequency measurement
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6376

Search results for: frequency measurement

376 Participatory Monitoring Strategy to Address Stakeholder Engagement Impact in Co-creation of NBS Related Project: The OPERANDUM Case

Authors: Teresa Carlone, Matteo Mannocchi

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In the last decade, a growing number of International Organizations are pushing toward green solutions for adaptation to climate change. This is particularly true in the field of Disaster Risk Reduction (DRR) and land planning, where Nature-Based Solutions (NBS) had been sponsored through funding programs and planning tools. Stakeholder engagement and co-creation of NBS is growing as a practice and research field in environmental projects, fostering the consolidation of a multidisciplinary socio-ecological approach in addressing hydro-meteorological risk. Even thou research and financial interests are constantly spread, the NBS mainstreaming process is still at an early stage as innovative concepts and practices make it difficult to be fully accepted and adopted by a multitude of different actors to produce wide scale societal change. The monitoring and impact evaluation of stakeholders’ participation in these processes represent a crucial aspect and should be seen as a continuous and integral element of the co-creation approach. However, setting up a fit for purpose-monitoring strategy for different contexts is not an easy task, and multiple challenges emerge. In this scenario, the Horizon 2020 OPERANDUM project, designed to address the major hydro-meteorological risks that negatively affect European rural and natural territories through the co-design, co-deployment, and assessment of Nature-based Solution, represents a valid case study to test a monitoring strategy from which set a broader, general and scalable monitoring framework. Applying a participative monitoring methodology, based on selected indicators list that combines quantitative and qualitative data developed within the activity of the project, the paper proposes an experimental in-depth analysis of the stakeholder engagement impact in the co-creation process of NBS. The main focus will be to spot and analyze which factors increase knowledge, social acceptance, and mainstreaming of NBS, promoting also a base-experience guideline to could be integrated with the stakeholder engagement strategy in current and future similar strongly collaborative approach-based environmental projects, such as OPERANDUM. Measurement will be carried out through survey submitted at a different timescale to the same sample (stakeholder: policy makers, business, researchers, interest groups). Changes will be recorded and analyzed through focus groups in order to highlight causal explanation and to assess the proposed list of indicators to steer the conduction of similar activities in other projects and/or contexts. The idea of the paper is to contribute to the construction of a more structured and shared corpus of indicators that can support the evaluation of the activities of involvement and participation of various levels of stakeholders in the co-production, planning, and implementation of NBS to address climate change challenges.

Keywords: co-creation and collaborative planning, monitoring, nature-based solution, participation & inclusion, stakeholder engagement

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375 Seawater Desalination for Production of Highly Pure Water Using a Hydrophobic PTFE Membrane and Direct Contact Membrane Distillation (DCMD)

Authors: Ahmad Kayvani Fard, Yehia Manawi

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Qatar’s primary source of fresh water is through seawater desalination. Amongst the major processes that are commercially available on the market, the most common large scale techniques are Multi-Stage Flash distillation (MSF), Multi Effect distillation (MED), and Reverse Osmosis (RO). Although commonly used, these three processes are highly expensive down to high energy input requirements and high operating costs allied with maintenance and stress induced on the systems in harsh alkaline media. Beside that cost, environmental footprint of these desalination techniques are significant; from damaging marine eco-system, to huge land use, to discharge of tons of GHG and huge carbon footprint. Other less energy consuming techniques based on membrane separation are being sought to reduce both the carbon footprint and operating costs is membrane distillation (MD). Emerged in 1960s, MD is an alternative technology for water desalination attracting more attention since 1980s. MD process involves the evaporation of a hot feed, typically below boiling point of brine at standard conditions, by creating a water vapor pressure difference across the porous, hydrophobic membrane. Main advantages of MD compared to other commercially available technologies (MSF and MED) and specially RO are reduction of membrane and module stress due to absence of trans-membrane pressure, less impact of contaminant fouling on distillate due to transfer of only water vapor, utilization of low grade or waste heat from oil and gas industries to heat up the feed up to required temperature difference across the membrane, superior water quality, and relatively lower capital and operating cost. To achieve the objective of this study, state of the art flat-sheet cross-flow DCMD bench scale unit was designed, commissioned, and tested. The objective of this study is to analyze the characteristics and morphology of the membrane suitable for DCMD through SEM imaging and contact angle measurement and to study the water quality of distillate produced by DCMD bench scale unit. Comparison with available literature data is undertaken where appropriate and laboratory data is used to compare a DCMD distillate quality with that of other desalination techniques and standards. Membrane SEM analysis showed that the PTFE membrane used for the study has contact angle of 127º with highly porous surface supported with less porous and bigger pore size PP membrane. Study on the effect of feed solution (salinity) and temperature on water quality of distillate produced from ICP and IC analysis showed that with any salinity and different feed temperature (up to 70ºC) the electric conductivity of distillate is less than 5 μS/cm with 99.99% salt rejection and proved to be feasible and effective process capable of consistently producing high quality distillate from very high feed salinity solution (i.e. 100000 mg/L TDS) even with substantial quality difference compared to other desalination methods such as RO and MSF.

Keywords: membrane distillation, waste heat, seawater desalination, membrane, freshwater, direct contact membrane distillation

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374 Financing the Welfare State in the United States: The Recent American Economic and Ideological Challenges

Authors: Rafat Fazeli, Reza Fazeli

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This paper focuses on the study of the welfare state and social wage in the leading liberal economy of the United States. The welfare state acquired a broad acceptance as a major socioeconomic achievement of the liberal democracy in the Western industrialized countries during the postwar boom period. The modern and modified vision of capitalist democracy offered, on the one hand, the possibility of high growth rate and, on the other hand, the possibility of continued progression of a comprehensive system of social support for a wider population. The economic crises of the 1970s, provided the ground for a great shift in economic policy and ideology in several Western countries, most notably the United States and the United Kingdom (and to a lesser extent Canada under Prime Minister Brian Mulroney). In the 1980s, the free market oriented reforms undertaken under Reagan and Thatcher greatly affected the economic outlook not only of the United States and the United Kingdom, but of the whole Western world. The movement which was behind this shift in policy is often called neo-conservatism. The neoconservatives blamed the transfer programs for the decline in economic performance during the 1970s and argued that cuts in spending were required to go back to the golden age of full employment. The agenda for both Reagan and Thatcher administrations was rolling back the welfare state, and their budgets included a wide range of cuts for social programs. The question is how successful were Reagan and Thatcher’s efforts to achieve retrenchment? The paper involves an empirical study concerning the distributive role of the welfare state in the two countries. Other studies have often concentrated on the redistributive effect of fiscal policy on different income brackets. This study examines the net benefit/ burden position of the working population with respect to state expenditures and taxes in the postwar period. This measurement will enable us to find out whether the working population has received a net gain (or net social wage). This study will discuss how the expansion of social expenditures and the trend of the ‘net social wage’ can be linked to distinct forms of economic and social organizations. This study provides an empirical foundation for analyzing the growing significance of ‘social wage’ or the collectivization of consumption and the share of social or collective consumption in total consumption of the working population in the recent decades. The paper addresses three other major questions. The first question is whether the expansion of social expenditures has posed any drag on capital accumulation and economic growth. The findings of this study provide an analytical foundation to evaluate the neoconservative claim that the welfare state is itself the source of economic stagnation that leads to the crisis of the welfare state. The second question is whether the increasing ideological challenges from the right and the competitive pressures of globalization have led to retrenchment of the American welfare states in the recent decades. The third question is how social policies have performed in the presence of the rising inequalities in the recent decades.

Keywords: the welfare state, social wage, The United States, limits to growth

Procedia PDF Downloads 201
373 Modelling the Behavior of Commercial and Test Textiles against Laundering Process by Statistical Assessment of Their Performance

Authors: M. H. Arslan, U. K. Sahin, H. Acikgoz-Tufan, I. Gocek, I. Erdem

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Various exterior factors have perpetual effects on textile materials during wear, use and laundering in everyday life. In accordance with their frequency of use, textile materials are required to be laundered at certain intervals. The medium in which the laundering process takes place have inevitable detrimental physical and chemical effects on textile materials caused by the unique parameters of the process inherently existing. Connatural structures of various textile materials result in many different physical, chemical and mechanical characteristics. Because of their specific structures, these materials have different behaviors against several exterior factors. By modeling the behavior of commercial and test textiles as group-wise against laundering process, it is possible to disclose the relation in between these two groups of materials, which will lead to better understanding of their behaviors in terms of similarities and differences against the washing parameters of the laundering. Thus, the goal of the current research is to examine the behavior of two groups of textile materials as commercial textiles and as test textiles towards the main washing machine parameters during laundering process such as temperature, load quantity, mechanical action and level of water amount by concentrating on shrinkage, pilling, sewing defects, collar abrasion, the other defects other than sewing, whitening and overall properties of textiles. In this study, cotton fabrics were preferred as commercial textiles due to the fact that garments made of cotton are the most demanded products in the market by the textile consumers in daily life. Full factorial experimental set-up was used to design the experimental procedure. All profiles always including all of the commercial and the test textiles were laundered for 20 cycles by commercial home laundering machine to investigate the effects of the chosen parameters. For the laundering process, a modified version of ‘‘IEC 60456 Test Method’’ was utilized. The amount of detergent was altered as 0.5% gram per liter depending on varying load quantity levels. Datacolor 650®, EMPA Photographic Standards for Pilling Test and visual examination were utilized to test and characterize the textiles. Furthermore, in the current study the relation in between commercial and test textiles in terms of their performance was deeply investigated by the help of statistical analysis performed by MINITAB® package program modeling their behavior against the parameters of the laundering process. In the experimental work, the behaviors of both groups of textiles towards washing machine parameters were visually and quantitatively assessed in dry state.

Keywords: behavior against washing machine parameters, performance evaluation of textiles, statistical analysis, commercial and test textiles

Procedia PDF Downloads 349
372 The Gender Criteria of Film Criticism: Creating the ‘Big’, Avoiding the Important

Authors: Eleni Karasavvidou

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Social and anthropological research, parallel to Gender Studies, highlighted the relationship between social structures and symbolic forms as an important field of interaction and recording of 'social trends.' Since the study of representations can contribute to the understanding of the social functions and power relations, they encompass. This ‘mirage,’ however, has not only to do with the representations themselves but also with the ways they are received and the film or critical narratives that are established as dominant or alternative. Cinema and the criticism of its cultural products are no exception. Even in the rapidly changing media landscape of the 21st century, movies remain an integral and widespread part of popular culture, making films an extremely powerful means of 'legitimizing' or 'delegitimizing' visions of domination and commonsensical gender stereotypes throughout society. And yet it is film criticism, the 'language per se,' that legitimizes, reinforces, rewards and reproduces (or at least ignores) the stereotypical depictions of female roles that remain common in the realm of film images. This creates the need for this issue to have emerged (also) in academic research questioning gender criteria in film reviews as part of the effort for an inclusive art and society. Qualitative content analysis is used to examine female roles in selected Oscar-nominated films against their reviews from leading websites and newspapers. This method was chosen because of the complex nature of the depictions in the films and the narratives they evoke. The films were divided into basic scenes depicting social functions, such as love and work relationships, positions of power and their function, which were analyzed by content analysis, with borrowings from structuralism (Gennette) and the local/universal images of intercultural philology (Wierlacher). In addition to the measurement of the general ‘representation-time’ by gender, other qualitative characteristics were also analyzed, such as: speaking time, sayings or key actions, overall quality of the character's action in relation to the development of the scenario and social representations in general, as well as quantitatively (insufficient number of female lead roles, fewer key supporting roles, relatively few female directors and people in the production chain and how they might affect screen representations. The quantitative analysis in this study was used to complement the qualitative content analysis. Then the focus shifted to the criteria of film criticism and to the rhetorical narratives that exclude or highlight in relation to gender identities and functions. In the criteria and language of film criticism, stereotypes are often reproduced or allegedly overturned within the framework of apolitical "identity politics," which mainly addresses the surface of a self-referential cultural-consumer product without connecting it more deeply with the material and cultural life. One of the prime examples of this failure is the Bechtel Test, which tracks whether female characters speak in a film regardless of whether women's stories are represented or not in the films analyzed. If perceived unbiased male filmmakers still fail to tell truly feminist stories, the same is the case with the criteria of criticism and the related interventions.

Keywords: representations, context analysis, reviews, sexist stereotypes

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371 Comparing Radiographic Detection of Simulated Syndesmosis Instability Using Standard 2D Fluoroscopy Versus 3D Cone-Beam Computed Tomography

Authors: Diane Ghanem, Arjun Gupta, Rohan Vijayan, Ali Uneri, Babar Shafiq

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Introduction: Ankle sprains and fractures often result in syndesmosis injuries. Unstable syndesmotic injuries result from relative motion between the distal ends of the tibia and fibula, anatomic juncture which should otherwise be rigid, and warrant operative management. Clinical and radiological evaluations of intraoperative syndesmosis stability remain a challenging task as traditional 2D fluoroscopy is limited to a uniplanar translational displacement. The purpose of this pilot cadaveric study is to compare the 2D fluoroscopy and 3D cone beam computed tomography (CBCT) stress-induced syndesmosis displacements. Methods: Three fresh-frozen lower legs underwent 2D fluoroscopy and 3D CIOS CBCT to measure syndesmosis position before dissection. Syndesmotic injury was simulated by resecting the (1) anterior inferior tibiofibular ligament (AITFL), the (2) posterior inferior tibiofibular ligament (PITFL) and the inferior transverse ligament (ITL) simultaneously, followed by the (3) interosseous membrane (IOM). Manual external rotation and Cotton stress test were performed after each of the three resections and 2D and 3D images were acquired. Relevant 2D and 3D parameters included the tibiofibular overlap (TFO), tibiofibular clear space (TCS), relative rotation of the fibula, and anterior-posterior (AP) and medial-lateral (ML) translations of the fibula relative to the tibia. Parameters were measured by two independent observers. Inter-rater reliability was assessed by intraclass correlation coefficient (ICC) to determine measurement precision. Results: Significant mismatches were found in the trends between the 2D and 3D measurements when assessing for TFO, TCS and AP translation across the different resection states. Using 3D CBCT, TFO was inversely proportional to the number of resected ligaments while TCS was directly proportional to the latter across all cadavers and ‘resection + stress’ states. Using 2D fluoroscopy, this trend was not respected under the Cotton stress test. 3D AP translation did not show a reliable trend whereas 2D AP translation of the fibula was positive under the Cotton stress test and negative under the external rotation. 3D relative rotation of the fibula, assessed using the Tang et al. ratio method and Beisemann et al. angular method, suggested slight overall internal rotation with complete resection of the ligaments, with a change < 2mm - threshold which corresponds to the commonly used buffer to account for physiologic laxity as per clinical judgment of the surgeon. Excellent agreement (>0.90) was found between the two independent observers for each of the parameters in both 2D and 3D (overall ICC 0.9968, 95% CI 0.995 - 0.999). Conclusions: The 3D CIOS CBCT appears to reliably depict the trend in TFO and TCS. This might be due to the additional detection of relevant rotational malpositions of the fibula in comparison to the standard 2D fluoroscopy which is limited to a single plane translation. A better understanding of 3D imaging may help surgeons identify the precise measurements planes needed to achieve better syndesmosis repair.

Keywords: 2D fluoroscopy, 3D computed tomography, image processing, syndesmosis injury

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370 A Longitudinal Study of Social Engagement in Classroom in Children with Autism Spectrum Disorder

Authors: Cecile Garry, Katia Rovira, Julie Brisson

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Autism Spectrum Disorder (ASD) is defined by a qualitative and quantitative impairment of social interaction. Indeed early intervention programs, such as the Early Start Denver Model (ESDM), aimed at encouraging the development of social skills. In classroom, the children need to be socially engaged to learn. Early intervention programs can thus be implemented in kindergarten schools. In these schools, ASD children have more opportunities to interact with their peers or adults than in elementary schools. However, the preschool children with ASD are less socially engaged than their typically developing peers in the classroom. They initiate, respond and maintain less the social interactions. In addition, they produce more responses than initiations. When they interact, the non verbal communication is more used than verbal or symbolic communication forms and they are more engaged with adults than with peers. Nevertheless, communicative patterns may vary according to the clinical profiles of ASD children. Indeed, the ASD children with better cognitive skills interact more with their peers and use more symbolic communication than the ASD children with a low cognitive level. ASD children with the less severe symptoms use more the verbal communication than ASD children with the more severe symptoms. Small groups and structured activities encourage coordinated joint engagement episodes in ASD children. Our goal is to evaluate ASD children’s social engagement development in class, with their peers or adults, during dyadic or group activities. Participants were 19 preschool children with ASD aged from 3 to 6 years old that benefited of an early intervention in special kindergarten schools. Severity of ASD symptoms was measured with the CARS at the beginning of the follow-up. Classroom situations of interaction were recorded during 10 minutes (5 minutes of dyadic interaction and 5 minutes of a group activity), every 2 months, during 10 months. Social engagement behaviors of children, including initiations, responses and imitation, directed to a peer or an adult, were then coded. The Observer software (Noldus) that allows to annotate behaviors was the coding system used. A double coding was conducted and revealed a good inter judges fidelity. Results show that ASD children were more often and longer socially engaged in dyadic than in groups situations. They were also more engaged with adults than with peers. Children with the less severe symptoms of ASD were more socially engaged in groups situations than children with the more severe symptoms of ASD. Then, ASD children with the less severe symptoms of ASD were more engaged with their peers than ASD children with the more severe symptoms of ASD. However, the engagement frequency increased during the 10 month of follow-up but only for ASD children with the more severe symptoms at the beginning. To conclude, these results highlighted the necessity of individualizing early intervention programs according to the clinical profile of the child.

Keywords: autism spectrum disorder, preschool children, developmental psychology, early interventions, social interactions

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369 Examining the Investment Behavior of Arab Women in the Stock Market

Authors: Razan Salem

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Gender plays a vital role in the stock markets because men and women differ in their behavior when investing in stocks. Accordingly, the role of gender differences in investment behavior is an increasingly important strand in the field of behavioral finance research. The investment behaviors of women relative to men have been examined in the behavioral finance literature, mainly for comparison purposes. Women's roles in the stock market have not been examined in the behavioral finance literature, however, particularly with respect to the Arab region. This study aims to contribute towards a better understanding of the investment behavior of Arab women (in regards to their risk tolerance, investment confidence, and investment literacy levels) relative to Arab men; using a sample from Arab women and men investors living in Saudi Arabia and Jordan. In order to achieve the study's main aim, the researcher used non-parametric tests, as Mann-Whitney U test, along with frequency distribution analysis to analyze the study’s primary data. The researcher distributed close-ended online questionnaires to a sample of 550 Arab male and female individuals investing in stocks in both Saudi Arabia and Jordan. The results confirm that the sample Arab women invest less in stocks compared to Arab men due to their risk-averse behaviors and limited confidence levels. The results also reveal that due to Arab women’s very low investment literacy levels, they fear from taking the risk and invest often in stocks relative to Arab men. Overall, the study’s main variables (risk tolerance, investment confidence, and investment literacy levels) have a combined effect on the investment behavior of Arab women and their limited participation in the stock market. Hence, this study is one of the very first studies that indicate the combined effect of the three main variables (which are usually studied separately in the existing literature) on the investment behavior of women, particularly Arab women. This study makes three important contributions to the growing literature on gender differences in investment behavior. First, while the behavioral finance literature documents evidence on gender differences in investment behaviors in many developed countries, there are very limited studies that investigate such differences in Arab countries. Arab women investors, generally, are ignored from the behavioral finance literature due probably to cultural barriers and data collection difficulties. Thus, this study extends the literature to include Arab women and their investment behaviors when trading stock relative to Arab men. Moreover, the study associates women investment literacy and confidence levels with their financial risk behaviors and participation in the stock market. This study provides direct evidence on Arab women's investment behaviors when trading stocks. Overall, studying Arab women investors is important to investigate whether the investment behavior identified for Western women investors are also found in Arab women investors.

Keywords: Arab women, gender differences, investment behavior, stock markets

Procedia PDF Downloads 174
368 A Flexible Piezoelectric - Polymer Composite for Non-Invasive Detection of Multiple Vital Signs of Human

Authors: Sarah Pasala, Elizabeth Zacharias

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Vital sign monitoring is crucial for both everyday health and medical diagnosis. A significant factor in assessing a human's health is their vital signs, which include heart rate, breathing rate, blood pressure, and electrocardiogram (ECG) readings. Vital sign monitoring has been the focus of many system and method innovations recently. Piezoelectrics are materials that convert mechanical energy into electrical energy and can be used for vital sign monitoring. Piezoelectric energy harvesters that are stretchable and flexible can detect very low frequencies like airflow, heartbeat, etc. Current advancements in piezoelectric materials and flexible sensors have made it possible to create wearable and implantable medical devices that can continuously monitor physiological signals in humans. But because of their non-biocompatible nature, they also produce a large amount of e-waste and require another surgery to remove the implant. This paper presents a biocompatible and flexible piezoelectric composite material for wearable and implantable devices that offers a high-performance platform for seamless and continuous monitoring of human physiological signals and tactile stimuli. It also addresses the issue of e-waste and secondary surgery. A Lead-free piezoelectric, SrBi4Ti4O15, is found to be suitable for this application because the properties can be tailored by suitable substitutions and also by varying the synthesis temperature protocols. In the present work, SrBi4Ti4O15 modified by rare-earth has been synthesized and studied. Coupling factors are calculated from resonant (fr) and anti-resonant frequencies (fa). It is observed that Samarium substitution in SBT has increased the Curie temperature, dielectric and piezoelectric properties. From impedance spectroscopy studies, relaxation, and non-Debye type behaviour are observed. The composite of bioresorbable poly(l-lactide) and Lead-free rare earth modified Bismuth Layered Ferroelectrics leads to a flexible piezoelectric device for non-invasive measurement of vital signs, such as heart rate, breathing rate, blood pressure, and electrocardiogram (ECG) readings and also artery pulse signals in near-surface arteries. These composites are suitable to detect slight movement of the muscles and joints. This Lead-free rare earth modified Bismuth Layered Ferroelectrics – polymer composite is synthesized using a ball mill and the solid-state double sintering method. XRD studies indicated the two phases in the composite. SEM studies revealed the grain size to be uniform and in the range of 100 nm. The electromechanical coupling factor is improved. The elastic constants are calculated and the mechanical flexibility is found to be improved as compared to the single-phase rare earth modified Bismuth Latered piezoelectric. The results indicate that this composite is suitable for the non-invasive detection of multiple vital signs of humans.

Keywords: composites, flexible, non-invasive, piezoelectric

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367 Supply Chain Analysis with Product Returns: Pricing and Quality Decisions

Authors: Mingming Leng

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

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

Procedia PDF Downloads 271
366 Storms Dynamics in the Black Sea in the Context of the Climate Changes

Authors: Eugen Rusu

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The objective of the work proposed is to perform an analysis of the wave conditions in the Black Sea basin. This is especially focused on the spatial and temporal occurrences and on the dynamics of the most extreme storms in the context of the climate changes. A numerical modelling system, based on the spectral phase averaged wave model SWAN, has been implemented and validated against both in situ measurements and remotely sensed data, all along the sea. Moreover, a successive correction method for the assimilation of the satellite data has been associated with the wave modelling system. This is based on the optimal interpolation of the satellite data. Previous studies show that the process of data assimilation improves considerably the reliability of the results provided by the modelling system. This especially concerns the most sensitive cases from the point of view of the accuracy of the wave predictions, as the extreme storm situations are. Following this numerical approach, it has to be highlighted that the results provided by the wave modelling system above described are in general in line with those provided by some similar wave prediction systems implemented in enclosed or semi-enclosed sea basins. Simulations of this wave modelling system with data assimilation have been performed for the 30-year period 1987-2016. Considering this database, the next step was to analyze the intensity and the dynamics of the higher storms encountered in this period. According to the data resulted from the model simulations, the western side of the sea is considerably more energetic than the rest of the basin. In this western region, regular strong storms provide usually significant wave heights greater than 8m. This may lead to maximum wave heights even greater than 15m. Such regular strong storms may occur several times in one year, usually in the wintertime, or in late autumn, and it can be noticed that their frequency becomes higher in the last decade. As regards the case of the most extreme storms, significant wave heights greater than 10m and maximum wave heights close to 20m (and even greater) may occur. Such extreme storms, which in the past were noticed only once in four or five years, are more recent to be faced almost every year in the Black Sea, and this seems to be a consequence of the climate changes. The analysis performed included also the dynamics of the monthly and annual significant wave height maxima as well as the identification of the most probable spatial and temporal occurrences of the extreme storm events. Finally, it can be concluded that the present work provides valuable information related to the characteristics of the storm conditions and on their dynamics in the Black Sea. This environment is currently subjected to high navigation traffic and intense offshore and nearshore activities and the strong storms that systematically occur may produce accidents with very serious consequences.

Keywords: Black Sea, extreme storms, SWAN simulations, waves

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365 Combined Effect of Vesicular System and Iontophoresis on Skin Permeation Enhancement of an Analgesic Drug

Authors: Jigar N. Shah, Hiral J. Shah, Praful D. Bharadia

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The major challenge faced by formulation scientists in transdermal drug delivery system is to overcome the inherent barriers related to skin permeation. The stratum corneum layer of the skin is working as the rate limiting step in transdermal transport and reduce drug permeation through skin. Many approaches have been used to enhance the penetration of drugs through this layer of the skin. The purpose of this study is to investigate the development and evaluation of a combined approach of drug carriers and iontophoresis as a vehicle to improve skin permeation of an analgesic drug. Iontophoresis is a non-invasive technique for transporting charged molecules into and through tissues by a mild electric field. It has been shown to effectively deliver a variety of drugs across the skin to the underlying tissue. In addition to the enhanced continuous transport, iontophoresis allows dose titration by adjusting the electric field, which makes personalized dosing feasible. Drug carrier could modify the physicochemical properties of the encapsulated molecule and offer a means to facilitate the percutaneous delivery of difficult-to-uptake substances. Recently, there are some reports about using liposomes, microemulsions and polymeric nanoparticles as vehicles for iontophoretic drug delivery. Niosomes, the nonionic surfactant-based vesicles that are essentially similar in properties to liposomes have been proposed as an alternative to liposomes. Niosomes are more stable and free from other shortcoming of liposomes. Recently, the transdermal delivery of certain drugs using niosomes has been envisaged and niosomes have proved to be superior transdermal nanocarriers. Proniosomes overcome some of the physical stability related problems of niosomes. The proniosomal structure was liquid crystalline-compact niosomes hybrid which could be converted into niosomes upon hydration. The combined use of drug carriers and iontophoresis could offer many additional benefits. The system was evaluated for Encapsulation Efficiency, vesicle size, zeta potential, Transmission Electron Microscopy (TEM), DSC, in-vitro release, ex-vivo permeation across skin and rate of hydration. The use of proniosomal gel as a vehicle for the transdermal iontophoretic delivery was evaluated in-vitro. The characteristics of the applied electric current, such as density, type, frequency, and on/off interval ratio were observed. The study confirms the synergistic effect of proniosomes and iontophoresis in improving the transdermal permeation profile of selected analgesic drug. It is concluded that proniosomal gel can be used as a vehicle for transdermal iontophoretic drug delivery under suitable electric conditions.

Keywords: iontophoresis, niosomes, permeation enhancement, transdermal delivery

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364 Life Cycle Assessment-Based Environmental Assessment of the Production and Maintenance of Wooden Windows

Authors: Pamela Del Rosario, Elisabetta Palumbo, Marzia Traverso

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The building sector plays an important role in addressing pressing environmental issues such as climate change and resource scarcity. The energy performance of buildings is considerably affected by the external envelope. In fact, a considerable proportion of the building energy demand is due to energy losses through the windows. Nevertheless, according to literature, to pay attention only to the contribution of windows to the building energy performance, i.e., their influence on energy use during building operation, could result in a partial evaluation. Hence, it is important to consider not only the building energy performance but also the environmental performance of windows, and this not only during the operational stage but along its complete life cycle. Life Cycle Assessment (LCA) according to ISO 14040:2006 and ISO 14044:2006+A1:2018 is one of the most adopted and robust methods to evaluate the environmental performance of products throughout their complete life cycle. This life-cycle based approach avoids the shift of environmental impacts of a life cycle stage to another, allowing to allocate them to the stage in which they originated and to adopt measures that optimize the environmental performance of the product. Moreover, the LCA method is widely implemented in the construction sector to assess whole buildings as well as construction products and materials. LCA is regulated by the European Standards EN 15978:2011, at the building level, and EN 15804:2012+A2:2019, at the level of construction products and materials. In this work, the environmental performance of wooden windows was assessed by implementing the LCA method and adopting primary data. More specifically, the emphasis is given to embedded and operational impacts. Furthermore, correlations are made between these environmental impacts and aspects such as type of wood and window transmittance. In the particular case of the operational impacts, special attention is set on the definition of suitable maintenance scenarios that consider the potential climate influence on the environmental impacts. For this purpose, a literature review was conducted, and expert consultation was carried out. The study underlined the variability of the embedded environmental impacts of wooden windows by considering different wood types and transmittance values. The results also highlighted the need to define appropriate maintenance scenarios for precise assessment results. It was found that both the service life and the window maintenance requirements in terms of treatment and its frequency are highly dependent not only on the wood type and its treatment during the manufacturing process but also on the weather conditions of the place where the window is installed. In particular, it became evident that maintenance-related environmental impacts were the highest for climate regions with the lowest temperatures and the greatest amount of precipitation.

Keywords: embedded impacts, environmental performance, life cycle assessment, LCA, maintenance stage, operational impacts, wooden windows

Procedia PDF Downloads 222
363 Five Years Analysis and Mitigation Plans on Adjustment Orders Impacts on Projects in Kuwait's Oil and Gas Sector

Authors: Rawan K. Al-Duaij, Salem A. Al-Salem

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Projects, the unique and temporary process of achieving a set of requirements have always been challenging; Planning the schedule and budget, managing the resources and risks are mostly driven by a similar past experience or the technical consultations of experts in the matter. With that complexity of Projects in Scope, Time, and execution environment, Adjustment Orders are tools to reflect changes to the original project parameters after Contract signature. Adjustment Orders are the official/legal amendments to the terms and conditions of a live Contract. Reasons for issuing Adjustment Orders arise from changes in Contract scope, technical requirement and specification resulting in scope addition, deletion, or alteration. It can be as well a combination of most of these parameters resulting in an increase or decrease in time and/or cost. Most business leaders (handling projects in the interest of the owner) refrain from using Adjustment Orders considering their main objectives of staying within budget and on schedule. Success in managing the changes results in uninterrupted execution and agreed project costs as well as schedule. Nevertheless, this is not always practically achievable. In this paper, a detailed study through utilizing Industrial Engineering & Systems Management tools such as Six Sigma, Data Analysis, and Quality Control were implemented on the organization’s five years records of the issued Adjustment Orders in order to investigate their prevalence, and time and cost impact. The analysis outcome revealed and helped to identify and categorize the predominant causations with the highest impacts, which were considered most in recommending the corrective measures to reach the objective of minimizing the Adjustment Orders impacts. Data analysis demonstrated no specific trend in the AO frequency in past five years; however, time impact is more than the cost impact. Although Adjustment Orders might never be avoidable; this analysis offers’ some insight to the procedural gaps, and where it is highly impacting the organization. Possible solutions are concluded such as improving project handling team’s coordination and communication, utilizing a blanket service contract, and modifying the projects gate system procedures to minimize the possibility of having similar struggles in future. Projects in the Oil and Gas sector are always evolving and demand a certain amount of flexibility to sustain the goals of the field. As it will be demonstrated, the uncertainty of project parameters, in adequate project definition, operational constraints and stringent procedures are main factors resulting in the need for Adjustment Orders and accordingly the recommendation will be to address that challenge.

Keywords: adjustment orders, data analysis, oil and gas sector, systems management

Procedia PDF Downloads 154
362 Social Entrepreneurship Core Dimensions and Influential Perspectives: An Exploratory Study

Authors: Filipa Lancastre, Carmen Lages, Filipe Santos

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The concept of social entrepreneurship (SE) remains ambiguous and deprived of a widely accepted operational definition. We argue that an awareness about the consensual constituent elements of SE from all key players from its ecosystem as well as a deeper understanding of apparently divergent perspectives will allow the different stakeholders (social entrepreneurs, corporations, investors, policymakers, the beneficiaries themselves) to bridge and cooperate for societal value co-creation in trying to solve our most pressing societal issues. To address our research question –what are the dimensions of SE that are consensual and controversial across existing perspectives? – We designed a two-step qualitative study. In a first step, we conducted an extensive literature review, collecting and analyzing 155 different SE definitions. From this initial step, we extracted and characterized three consensual and six controversial dimensions of the SE concept. In a second step, we conducted 20 semi-structured interviews with practitioners that are actively involved in the SE field. The goal of this second step was to verify if the literature did not capture any key dimension, understand how the dimensions related to each other and to understand the rationale behind them. The dimensions of the SE concept were extracted based on the relevance of each theme and on the theoretical relationship among them. To identify the relevance, we used as a proxy the frequency of each theme was referred to in our sample of definitions. To understand relationships, as identified in the previous section, we included concepts from both the management and psychology literature, such as the Entrepreneurial Orientation concept from the entrepreneurship literature, the Subjective Well Being construct from psychology literature, and the Resource-Based Theory from the strategy literature. This study has two main contributions; First, the identification of (consensual and controversial) dimensions of SE that exist across scattered definitions from the academic and practitioner literature. Second, a framework that parsimoniously synthesizes four dominant perspectives of SE and relates them with the SE dimensions. Assuming the contested nature of the SE concept, it is not expected that these views will be reconciled at the academic or practitioner field level. In future research, academics can, however, be aware of the existence of different understandings of SE and avoid bias towards a single view, developing holistic studies on SE phenomena or comparing differences by studying their underlying assumptions. Additionally, it is important that researchers make explicit the perspective they are embracing to ensure consistency among the research question, sampling procedures and implications of results. At the practitioner level, individuals or groups following different logics are predictably mutually suspicious and might benefit from taking stock of other perspectives on SE, building bridges and fostering cross-fertilization to the benefit of the SE ecosystem for which all contribute.

Keywords: social entrepreneurship, conceptualization, dimensions, perspectives

Procedia PDF Downloads 168
361 Effects of Cow Milk and Camel Milk on Improving Covered Distance in the 6-Minute Walk Test Performed by Obese Young Adults

Authors: Mo'ath F. Bataineh

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Exercise is highly effective against obesity. Milk contains several components that support exercising and physical performance. However, there is a lack of published studies on the relationship between camel milk and ability to exercise. A pilot study was conducted with the purpose of comparing the impact of milk type (Cow vs Camel) compared with water on physical performance. Seven male obese participants (age: 20.3 ± 1.5 years; BMI: 35.7 ± 2.7 kg/m2; resting heart rate: 92.7 ± 4.7 beats per minute; training frequency: 4.4 ± 0.8 days/week) were recruited for this pilot study. In a randomized counterbalanced crossover design, participants took part in 3 trials that included ingesting 3 different pre workout drinks in a random order. The pre workout drinks were water (W), whole cow milk (CW), and whole camel milk (CM). On each trial day, participants were asked to report to the laboratory after an overnight fasting. Following a 15-minute short recovery period after their arrival to the laboratory, each participant was presented with a 500 ml of the assigned experimental drink and were asked to ingest it in one minute and at least 120 minutes prior to performing the 6-minute walk test. All drinks were presented at room temperature. Trials with different experimental drinks were performed on separate days. Participants were given at least 4 days of washout period between trials. The trial order was randomized to avoid bias due to learning effect. The 6-minute walk test was performed by all participants and immediately at the conclusion of the test, the covered distance in meters and the rating of perceived exertion (RPE) were recorded. All data were analysed using SPSS software (Version 29.0). The repeated measures ANOVA testing of collected data showed a significant main effect for treatment on covered distance in meters, F (2, 8) = 5.794, p=0.028 with a large effect size (partial eta squared (ηp2) =0.592). Also, LSD post hoc pairwise comparison analysis revealed that Camel milk and Cow milk were significantly (p = 0.044 and p = 0.020 respectively) superior to water in improving the covered distance during the test and that Camel milk tended to be better than Cow’s milk. The RPE values were not significantly different between experimental drinks (p>0.05). In conclusion, milk is superior to water as a pre workout drink, and camel milk is comparable to cow’s milk in enhancing ability to support a higher level of performance compared with water, therefore, camel milk could be used to replace cow’s milk as a suitable pre-exercise drink without expecting any negative consequences on physical performance. The fact that these positive results were obtained with obese individuals should encourage using camel milk without the fear of disturbing physical performance in other weight categories.

Keywords: camel milk, cow milk, obesity, physical performance, pre-workout drink

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360 Building Environmental Citizenship in Spain: Urban Movements and Ecologist Protest in Las Palmas De Gran Canaria, 1970-1983

Authors: Juan Manuel Brito-Diaz

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The emergence of urban environmentalism in Spain is related to the processes of economic transformation and growing urbanization that occurred during the end of the Franco regime and the democratic transition. This paper analyzes the urban environmental mobilizations and their impacts as relevant democratizing agents in the processes of political change in cities. It’s an under-researched topic and studies on environmental movements in Spain have paid little attention to it. This research takes as its starting point the close link between democratization and environmentalism, since it considers that environmental conflicts are largely a consequence of democratic problems, and that the impacts of environmental movements are directly linked to the democratization. The study argues that the environmental movements that emerged in Spain at the end of the dictatorship and the democratic transition are an important part of the broad and complex associative fabric that promoted the democratization process. The research focuses on investigating the environmental protest in Las Palmas de Gran Canaria—the most important city in the Canary Islands—between 1970 and 1983, concurrently with the last local governments of the dictatorship and the first democratic city councils. As it is a case study, it opens up the possibility to ask multiple specific questions and assess each of the responses obtained. Although several research methodologies have been applied, such as the analysis of historical archives documentation or oral history interviews, mainly a very widespread methodology in the sociology of social movements, although very little used by social historians, has been used: the Protest Event Analysis (PEA). This methodology, which consists of generating a catalog of protest events by coding data around previously established variables, has allowed me to map, analyze and interpret the occurrence of protests over time and space, and associated factors, through content analysis. For data collection, news from local newspapers have provided a large enough sample to analyze the properties of social protest -frequency, size, demands, forms, organizers, etc.—and relate them to another type of information related to political structures and mobilization repertoires, encouraging the establishment of connections between the protest and the political impacts of urban movements. Finally, the study argues that the environmental movements of this period were essential to the construction of the new democratic city in Spain, not only because they established the issues of sustainability and urban environmental justice on the public agenda, but also because they proposed that conflicts derived from such matters should ultimately be resolved through public deliberation and citizen participation.

Keywords: democratization, environmental movements, political impacts, social movements

Procedia PDF Downloads 173
359 Assessing Measures and Caregiving Experiences of Thai Caregivers of Persons with Dementia

Authors: Piyaorn Wajanatinapart, Diane R. Lauver

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The number of persons with dementia (PWD) has increased. Informal caregivers are the major providing care. They can have perceived gains and burdens. Caregivers who reported high in perceived gains may report low in burdens and better health. Gaps of caregiving literature were: no report psychometrics in a few studies and unclear definitions of gains; most studies with no theory-guided and conducting in Western countries; not fully described relationships among caregiving variables: motivations, satisfaction with psychological needs, social support, gains, burdens, and physical and psycho-emotional health. Those gaps were filled by assessing psychometric properties of selected measures, providing clearly definitions of gains, using self-determination theory (SDT) to guide the study, and developing the study in Thailand. The study purposes were to evaluate six measures for internal consistency reliability, content validity, and construct validity. This study also examined relationships of caregiving variables: motivations (controlled and autonomous motivations), satisfaction with psychological needs (autonomy, competency, and relatedness), perceived social support, perceived gains, perceived burdens, and physical and psycho-emotional health. This study was a cross-sectional and correlational descriptive design with two convenience samples. Sample 1 was five Thai experts to assess content validity of measures. Sample 2 was 146 Thai caregivers of PWD to assess construct validity, reliability, and relationships among caregiving variables. Experts rated questionnaires and sent them back via e-mail. Caregivers answered questionnaires at clinics of four Thai hospitals. Data analysis was used descriptive statistics and bivariate and multivariate analyses using the composite indicator structural equation model to control measurement errors. For study results, most caregivers were female (82%), middle age (M =51.1, SD =11.9), and daughters (57%). They provided care for 15 hours/day with 4.6 years. The content validity indices of items and scales were .80 or higher for clarity and relevance. Experts suggested item revisions. Cronbach’s alphas were .63 to .93 of ten subscales of four measures and .26 to .57 of three subscales. The gain scale was acceptable for construct validity. With controlling covariates, controlled motivations, the satisfaction with three subscales of psychological needs, and perceived social support had positive relationships with physical and psycho-emotional health. Both satisfaction with autonomy subscale and perceived social support had negative relationship with perceived burdens. The satisfaction with three subscales of psychological needs had positive relationships among them. Physical and psycho-emotional health subscales had positive relationships with each other. Furthermore, perceived burdens had negative relationships with physical and psycho-emotional health. This study was the first use SDT to describe relationships of caregiving variables in Thailand. Caregivers’ characteristics were consistent with literature. Four measures were valid and reliable except two measures. Breadth knowledge about relationships was provided. Interpretation of study results was cautious because of using same sample to evaluate psychometric properties of measures and relationships of caregiving variables. Researchers could use four measures for further caregiving studies. Using a theory would help describe concepts, propositions, and measures used. Researchers may examine the satisfaction with psychological needs as mediators. Future studies to collect data with caregivers in communities are needed.

Keywords: caregivers, caregiving, dementia, measures

Procedia PDF Downloads 296
358 Single Pass Design of Genetic Circuits Using Absolute Binding Free Energy Measurements and Dimensionless Analysis

Authors: Iman Farasat, Howard M. Salis

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Engineered genetic circuits reprogram cellular behavior to act as living computers with applications in detecting cancer, creating self-controlling artificial tissues, and dynamically regulating metabolic pathways. Phenemenological models are often used to simulate and design genetic circuit behavior towards a desired behavior. While such models assume that each circuit component’s function is modular and independent, even small changes in a circuit (e.g. a new promoter, a change in transcription factor expression level, or even a new media) can have significant effects on the circuit’s function. Here, we use statistical thermodynamics to account for the several factors that control transcriptional regulation in bacteria, and experimentally demonstrate the model’s accuracy across 825 measurements in several genetic contexts and hosts. We then employ our first principles model to design, experimentally construct, and characterize a family of signal amplifying genetic circuits (genetic OpAmps) that expand the dynamic range of cell sensors. To develop these models, we needed a new approach to measuring the in vivo binding free energies of transcription factors (TFs), a key ingredient of statistical thermodynamic models of gene regulation. We developed a new high-throughput assay to measure RNA polymerase and TF binding free energies, requiring the construction and characterization of only a few constructs and data analysis (Figure 1A). We experimentally verified the assay on 6 TetR-homolog repressors and a CRISPR/dCas9 guide RNA. We found that our binding free energy measurements quantitatively explains why changing TF expression levels alters circuit function. Altogether, by combining these measurements with our biophysical model of translation (the RBS Calculator) as well as other measurements (Figure 1B), our model can account for changes in TF binding sites, TF expression levels, circuit copy number, host genome size, and host growth rate (Figure 1C). Model predictions correctly accounted for how these 8 factors control a promoter’s transcription rate (Figure 1D). Using the model, we developed a design framework for engineering multi-promoter genetic circuits that greatly reduces the number of degrees of freedom (8 factors per promoter) to a single dimensionless unit. We propose the Ptashne (Pt) number to encapsulate the 8 co-dependent factors that control transcriptional regulation into a single number. Therefore, a single number controls a promoter’s output rather than these 8 co-dependent factors, and designing a genetic circuit with N promoters requires specification of only N Pt numbers. We demonstrate how to design genetic circuits in Pt number space by constructing and characterizing 15 2-repressor OpAmp circuits that act as signal amplifiers when within an optimal Pt region. We experimentally show that OpAmp circuits using different TFs and TF expression levels will only amplify the dynamic range of input signals when their corresponding Pt numbers are within the optimal region. Thus, the use of the Pt number greatly simplifies the genetic circuit design, particularly important as circuits employ more TFs to perform increasingly complex functions.

Keywords: transcription factor, synthetic biology, genetic circuit, biophysical model, binding energy measurement

Procedia PDF Downloads 465
357 Design of Photonic Crystal with Defect Layer to Eliminate Interface Corrugations for Obtaining Unidirectional and Bidirectional Beam Splitting under Normal Incidence

Authors: Evrim Colak, Andriy E. Serebryannikov, Pavel V. Usik, Ekmel Ozbay

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Working with a dielectric photonic crystal (PC) structure which does not include surface corrugations, unidirectional transmission and dual-beam splitting are observed under normal incidence as a result of the strong diffractions caused by the embedded defect layer. The defect layer has twice the period of the regular PC segments which sandwich the defect layer. Although the PC has even number of rows, the structural symmetry is broken due to the asymmetric placement of the defect layer with respect to the symmetry axis of the regular PC. The simulations verify that efficient splitting and occurrence of strong diffractions are related to the dispersion properties of the Floquet-Bloch modes of the photonic crystal. Unidirectional and bi-directional splitting, which are associated with asymmetric transmission, arise due to the dominant contribution of the first positive and first negative diffraction orders. The effect of the depth of the defect layer is examined by placing single defect layer in varying rows, preserving the asymmetry of PC. Even for deeply buried defect layer, asymmetric transmission is still valid even if the zeroth order is not coupled. This transmission is due to evanescent waves which reach to the deeply embedded defect layer and couple to higher order modes. In an additional selected performance, whichever surface is illuminated, i.e., in both upper and lower surface illumination cases, incident beam is split into two beams of equal intensity at the output surface where the intensity of the out-going beams are equal for both illumination cases. That is, although the structure is asymmetric, symmetric bidirectional transmission with equal transmission values is demonstrated and the structure mimics the behavior of symmetric structures. Finally, simulation studies including the examination of a coupled-cavity defect for two different permittivity values (close to the permittivity values of GaAs or Si and alumina) reveal unidirectional splitting for a wider band of operation in comparison to the bandwidth obtained in the case of a single embedded defect layer. Since the dielectric materials that are utilized are low-loss and weakly dispersive in a wide frequency range including microwave and optical frequencies, the studied structures should be scalable to the mentioned ranges.

Keywords: asymmetric transmission, beam deflection, blazing, bi-directional splitting, defect layer, dual beam splitting, Floquet-Bloch modes, isofrequency contours, line defect, oblique incidence, photonic crystal, unidirectionality

Procedia PDF Downloads 177
356 Developing and Shake Table Testing of Semi-Active Hydraulic Damper as Active Interaction Control Device

Authors: Ming-Hsiang Shih, Wen-Pei Sung, Shih-Heng Tung

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Semi-active control system for structure under excitation of earthquake provides with the characteristics of being adaptable and requiring low energy. DSHD (Displacement Semi-Active Hydraulic Damper) was developed by our research team. Shake table test results of this DSHD installed in full scale test structure demonstrated that this device brought its energy-dissipating performance into full play for test structure under excitation of earthquake. The objective of this research is to develop a new AIC (Active Interaction Control Device) and apply shake table test to perform its dissipation of energy capability. This new proposed AIC is converting an improved DSHD (Displacement Semi-Active Hydraulic Damper) to AIC with the addition of an accumulator. The main concept of this energy-dissipating AIC is to apply the interaction function of affiliated structure (sub-structure) and protected structure (main structure) to transfer the input seismic force into sub-structure to reduce the structural deformation of main structure. This concept is tested using full-scale multi-degree of freedoms test structure, installed with this proposed AIC subjected to external forces of various magnitudes, for examining the shock absorption influence of predictive control, stiffness of sub-structure, synchronous control, non-synchronous control and insufficient control position. The test results confirm: (1) this developed device is capable of diminishing the structural displacement and acceleration response effectively; (2) the shock absorption of low precision of semi-active control method did twice as much seismic proof efficacy as that of passive control method; (3) active control method may not exert a negative influence of amplifying acceleration response of structure; (4) this AIC comes into being time-delay problem. It is the same problem of ordinary active control method. The proposed predictive control method can overcome this defect; (5) condition switch is an important characteristics of control type. The test results show that synchronism control is very easy to control and avoid stirring high frequency response. This laboratory results confirm that the device developed in this research is capable of applying the mutual interaction between the subordinate structure and the main structure to be protected is capable of transforming the quake energy applied to the main structure to the subordinate structure so that the objective of minimizing the deformation of main structural can be achieved.

Keywords: DSHD (Displacement Semi-Active Hydraulic Damper), AIC (Active Interaction Control Device), shake table test, full scale structure test, sub-structure, main-structure

Procedia PDF Downloads 511
355 Influence of Non-Formal Physical Education Curriculum, Based on Olympic Pedagogy, for 11-13 Years Old Children Physical Development

Authors: Asta Sarkauskiene

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The pedagogy of Olympic education is based upon the main idea of P. de Coubertin, that physical education can and has to support the education of the perfect person, the one who was an aspiration in archaic Greece, when it was looking towards human as a one whole, which is composed of three interconnected functions: physical, psychical and spiritual. The following research question was formulated in the present study: What curriculum of non-formal physical education in school can positively influence physical development of 11-13 years old children? The aim of this study was to formulate and implement curriculum of non-formal physical education, based on Olympic pedagogy, and assess its effectiveness for physical development of 11-13 years old children. The research was conducted in two stages. In the first stage 51 fifth grade children (Mage = 11.3 years) participated in a quasi-experiment for two years. Children were organized into 2 groups: E and C. Both groups shared the duration (1 hour) and frequency (twice a week) but were different in their education curriculum. Experimental group (E) worked under the program developed by us. Priorities of the E group were: training of physical powers in unity with psychical and spiritual powers; integral growth of physical development, physical activity, physical health, and physical fitness; integration of children with lower health and physical fitness level; content that corresponds children needs, abilities, physical and functional powers. Control group (C) worked according to NFPE programs prepared by teachers and approved by school principal and school methodical group. Priorities of the C group were: motion actions teaching and development; physical qualities training; training of the most physically capable children. In the second stage (after four years) 72 sixth graders (Mage = 13.00) attended in the research from the same comprehensive schools. Children were organized into first and second groups. The curriculum of the first group was modified and the second - the same as group C. The focus groups conducted anthropometric (height, weight, BMI) and physiometric (VC, right and left handgrip strength) measurements. Dependent t test indicated that over two years E and C group girls and boys height, weight, right and left handgrip strength indices increased significantly, p < 0.05. E group girls and boys BMI indices did not change significantly, p > 0.05, i.e. height and weight ratio of girls, who participated in NFPE in school, became more proportional. C group girls VC indices did not differ significantly, p > 0.05. Independent t test indicated that in the first and second research stage differences of anthropometric and physiometric measurements of the groups are not significant, p > 0.05. Formulated and implemented curriculum of non-formal education in school, based on olympic pedagogy, had the biggest positive influence on decreasing 11-13 years old children level of BMI and increasing level of VC.

Keywords: non – formal physical education, olympic pedagogy, physical development, health sciences

Procedia PDF Downloads 555
354 Impact of Individual and Neighborhood Social Capital on the Health Status of the Pregnant Women in Riyadh City, Saudi Arabia

Authors: Abrar Almutairi, Alyaa Farouk, Amal Gouda

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Background: Social capital is a factor that helps in bonding in a social network. The individual and the neighborhood social capital affect the health status of members of a particular society. In addition, to the influence of social health on the health of the population, social health has a significant effect on women, especially those with pregnancy. Study objective was to assess the impact of the social capital on the health status of pregnant women Design: A descriptive crosssectional correlational design was utilized in this study. Methods: A convenient sample of 210 pregnant women who attended the outpatient antenatal clinicsfor follow-up in King Fahad hospital (Ministry of National Guard Health Affairs/Riyadh) and King Abdullah bin Abdelaziz University Hospital (KAAUH, Ministry of Education /Riyadh) were included in the study. Data was collected using a self-administered questionnaire that was developed by the researchers based on the “World Bank Social Capital Assessment Tool” and SF-36 questionnaire (Short Form Health Survey). The questionnaire consists of 4 parts to collect information regarding socio-demographic data, obstetric and gynecological history, general scale of health status and social activity during pregnancy and the social capital of the study participants, with different types of questions such as multiple-choice questions, polar questions, and Likert scales. Data analysis was carried out by using Statistical Package for the Social Sciences version 23. Descriptive statistic as frequency, percentage, mean, and standard deviation was used to describe the sample characteristics, and the simple linear regression test was used to assess the relationship between the different variables, with level of significance P≤0.005. Result: This study revealed that only 31.1% of the study participants perceived that they have good general health status. About two thirds (62.8%) of the participants have moderate social capital, more than one ten (11.2٪) have high social capital and more than a quarter (26%) of them have low social capital. All dimensions of social capital except for empowerment and political action had positive significant correlations with the health status of pregnant women with P value ranging from 0.001 to 0.010in all dimensions. In general, the social capital showed high statistically significant association with the health status of the pregnant (P=0.002). Conclusion: Less than one third of the study participants had good perceived health status, and the majority of the study participants have moderate social capital, with only about one ten of them perceived that they have high social capital. Finally, neighborhood residency area, family size, sufficiency of income, past medical and surgical history and parity of the study participants were all significantly impacting the assessed health domains of the pregnant women.

Keywords: impact, social capital, health status, pregnant women

Procedia PDF Downloads 48
353 High-Pressure Polymorphism of 4,4-Bipyridine Hydrobromide

Authors: Michalina Aniola, Andrzej Katrusiak

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4,4-Bipyridine is an important compound often used in chemical practice and more recently frequently applied for designing new metal organic framework (MoFs). Here we present a systematic high-pressure study of its hydrobromide salt. 4,4-Bipyridine hydrobromide monohydrate, 44biPyHBrH₂O, at ambient-pressure is orthorhombic, space group P212121 (phase a). Its hydrostatic compression shows that it is stable to 1.32 GPa at least. However, the recrystallization above 0.55 GPa reveals a new hidden b-phase (monoclinic, P21/c). Moreover, when the 44biPyHBrH2O is heated to high temperature the chemical reactions of this compound in methanol solution can be observed. High-pressure experiments were performed using a Merrill-Bassett diamond-anvil cell (DAC), modified by mounting the anvils directly on the steel supports, and X-ray diffraction measurements were carried out on a KUMA and Excalibur diffractometer equipped with an EOS CCD detector. At elevated pressure, the crystal of 44biPyHBrH₂O exhibits several striking and unexpected features. No signs of instability of phase a were detected to 1.32 GPa, while phase b becomes stable at above 0.55 GPa, as evidenced by its recrystallizations. Phases a and b of 44biPyHBrH2O are partly isostructural: their unit-cell dimensions and the arrangement of ions and water molecules are similar. In phase b the HOH-Br- chains double the frequency of their zigzag motifs, compared to phase a, and the 44biPyH+ cations change their conformation. Like in all monosalts of 44biPy determined so far, in phase a the pyridine rings are twisted by about 30 degrees about bond C4-C4 and in phase b they assume energy-unfavorable planar conformation. Another unusual feature of 44biPyHBrH2O is that all unit-cell parameters become longer on the transition from phase a to phase b. Thus the volume drop on the transition to high-pressure phase b totally depends on the shear strain of the lattice. Higher temperature triggers chemical reactions of 44biPyHBrH2O with methanol. When the saturated methanol solution compound precipitated at 0.1 GPa and temperature of 423 K was required to dissolve all the sample, the subsequent slow recrystallization at isochoric conditions resulted in disalt 4,4-bipyridinium dibromide. For the 44biPyHBrH2O sample sealed in the DAC at 0.35 GPa, then dissolved at isochoric conditions at 473 K and recrystallized by slow controlled cooling, a reaction of N,N-dimethylation took place. It is characteristic that in both high-pressure reactions of 44biPyHBrH₂O the unsolvated disalt products were formed and that free base 44biPy and H₂O remained in the solution. The observed reactions indicate that high pressure destabilized ambient-pressure salts and favors new products. Further studies on pressure-induced reactions are carried out in order to better understand the structural preferences induced by pressure.

Keywords: conformation, high-pressure, negative area compressibility, polymorphism

Procedia PDF Downloads 237
352 The Role of Serum Fructosamine as a Monitoring Tool in Gestational Diabetes Mellitus Treatment in Vietnam

Authors: Truong H. Le, Ngoc M. To, Quang N. Tran, Luu T. Cao, Chi V. Le

Abstract:

Introduction: In Vietnam, the current monitoring and treatment for ordinary diabetic patient mostly based on glucose monitoring with HbA1c test for every three months (recommended goal is HbA1c < 6.5%~7%). For diabetes in pregnant women or Gestational diabetes mellitus (GDM), glycemic control until the time of delivery is extremly important because it could reduce significantly medical implications for both the mother and the child. Besides, GDM requires continuos glucose monitoring at least every two weeks and therefore an alternative marker of glycemia for short-term control is considering a potential tool for the healthcare providers. There are published studies have indicated that the glycosylated serum protein is a better indicator than glycosylated hemoglobin in GDM monitoring. Based on the actual practice in Vietnam, this study was designed to evaluate the role of serum fructosamine as a monitoring tool in GDM treament and its correlations with fasting blood glucose (G0), 2-hour postprandial glucose (G2) and glycosylated hemoglobin (HbA1c). Methods: A cohort study on pregnant women diagnosed with GDM by the 75-gram oralglucose tolerance test was conducted at Endocrinology Department, Cho Ray hospital, Vietnam from June 2014 to March 2015. Cho Ray hospital is the final destination for GDM patient in the southern of Vietnam, the study population has many sources from other pronvinces and therefore researchers belive that this demographic characteristic can help to provide the study result as a reflection for the whole area. In this study, diabetic patients received a continuos glucose monitoring method which consists of bi-weekly on-site visit every 2 weeks with glycosylated serum protein test, fasting blood glucose test and 2-hour postprandial glucose test; HbA1c test for every 3 months; and nutritious consultance for daily diet program. The subjects still received routine treatment at the hospital, with tight follow-up from their healthcare providers. Researchers recorded bi-weekly health conditions, serum fructosamine level and delivery outcome from the pregnant women, using Stata 13 programme for the analysis. Results: A total of 500 pregnant women was enrolled and follow-up in this study. Serum fructosamine level was found to have a light correlation with G0 ( r=0.3458, p < 0.001) and HbA1c ( r=0.3544, p < 0.001), and moderately correlated with G2 ( r=0.4379, p < 0.001). During study timeline, the delivery outcome of 287 women were recorded with the average age of 38.5 ± 1.5 weeks, 9% of them have macrosomia, 2.8% have premature birth before week 35th and 9.8% have premature birth before week 37th; 64.8% of cesarean section and none of them have perinatal or neonatal mortality. The study provides a reference interval of serum fructosamine for GDM patient was 112.9 ± 20.7 μmol/dL. Conclusion: The present results suggests that serum fructosamine is as effective as HbA1c as a reflection of blood glucose control in GDM patient, with a positive result in delivery outcome (0% perinatal or neonatal mortality). The reference value of serum fructosamine measurement provided a potential monitoring utility in GDM treatment for hospitals in Vietnam. Healthcare providers in Cho Ray hospital is considering to conduct more studies to test this reference as a target value in their GDM treatment and monitoring.

Keywords: gestational diabetes mellitus, monitoring tool, serum fructosamine, Vietnam

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351 An Aptasensor Based on Magnetic Relaxation Switch and Controlled Magnetic Separation for the Sensitive Detection of Pseudomonas aeruginosa

Authors: Fei Jia, Xingjian Bai, Xiaowei Zhang, Wenjie Yan, Ruitong Dai, Xingmin Li, Jozef Kokini

Abstract:

Pseudomonas aeruginosa is a Gram-negative, aerobic, opportunistic human pathogen that is present in the soil, water, and food. This microbe has been recognized as a representative food-borne spoilage bacterium that can lead to many types of infections. Considering the casualties and property loss caused by P. aeruginosa, the development of a rapid and reliable technique for the detection of P. aeruginosa is crucial. The whole-cell aptasensor, an emerging biosensor using aptamer as a capture probe to bind to the whole cell, for food-borne pathogens detection has attracted much attention due to its convenience and high sensitivity. Here, a low-field magnetic resonance imaging (LF-MRI) aptasensor for the rapid detection of P. aeruginosa was developed. The basic detection principle of the magnetic relaxation switch (MRSw) nanosensor lies on the ‘T₂-shortening’ effect of magnetic nanoparticles in NMR measurements. Briefly speaking, the transverse relaxation time (T₂) of neighboring water protons get shortened when magnetic nanoparticles are clustered due to the cross-linking upon the recognition and binding of biological targets, or simply when the concentration of the magnetic nanoparticles increased. Such shortening is related to both the state change (aggregation or dissociation) and the concentration change of magnetic nanoparticles and can be detected using NMR relaxometry or MRI scanners. In this work, two different sizes of magnetic nanoparticles, which are 10 nm (MN₁₀) and 400 nm (MN₄₀₀) in diameter, were first immobilized with anti- P. aeruginosa aptamer through 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) chemistry separately, to capture and enrich the P. aeruginosa cells. When incubating with the target, a ‘sandwich’ (MN₁₀-bacteria-MN₄₀₀) complex are formed driven by the bonding of MN400 with P. aeruginosa through aptamer recognition, as well as the conjugate aggregation of MN₁₀ on the surface of P. aeruginosa. Due to the different magnetic performance of the MN₁₀ and MN₄₀₀ in the magnetic field caused by their different saturation magnetization, the MN₁₀-bacteria-MN₄₀₀ complex, as well as the unreacted MN₄₀₀ in the solution, can be quickly removed by magnetic separation, and as a result, only unreacted MN₁₀ remain in the solution. The remaining MN₁₀, which are superparamagnetic and stable in low field magnetic field, work as a signal readout for T₂ measurement. Under the optimum condition, the LF-MRI platform provides both image analysis and quantitative detection of P. aeruginosa, with the detection limit as low as 100 cfu/mL. The feasibility and specificity of the aptasensor are demonstrated in detecting real food samples and validated by using plate counting methods. Only two steps and less than 2 hours needed for the detection procedure, this robust aptasensor can detect P. aeruginosa with a wide linear range from 3.1 ×10² cfu/mL to 3.1 ×10⁷ cfu/mL, which is superior to conventional plate counting method and other molecular biology testing assay. Moreover, the aptasensor has a potential to detect other bacteria or toxins by changing suitable aptamers. Considering the excellent accuracy, feasibility, and practicality, the whole-cell aptasensor provides a promising platform for a quick, direct and accurate determination of food-borne pathogens at cell-level.

Keywords: magnetic resonance imaging, meat spoilage, P. aeruginosa, transverse relaxation time

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350 Molecular Migration in Polyvinyl Acetate Matrix: Impact of Compatibility, Number of Migrants and Stress on Surface and Internal Microstructure

Authors: O. Squillace, R. L. Thompson

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Migration of small molecules to, and across the surface of polymer matrices is a little-studied problem with important industrial applications. Tackifiers in adhesives, flavors in foods and binding agents in paints all present situations where the function of a product depends on the ability of small molecules to migrate through a polymer matrix to achieve the desired properties such as softness, dispersion of fillers, and to deliver an effect that is felt (or tasted) on a surface. It’s been shown that the chemical and molecular structure, surface free energies, phase behavior, close environment and compatibility of the system, influence the migrants’ motion. When differences in behavior, such as occurrence of segregation to the surface or not, are observed it is then of crucial importance to identify and get a better understanding of the driving forces involved in the process of molecular migration. In this aim, experience is meant to be allied with theory in order to deliver a validated theoretical and computational toolkit to describe and predict these phenomena. The systems that have been chosen for this study aim to address the effect of polarity mismatch between the migrants and the polymer matrix and that of a second migrant over the first one. As a non-polar resin polymer, polyvinyl acetate is used as the material to which more or less polar migrants (sorbitol, carvone, octanoic acid (OA), triacetin) are to be added. Through contact angle measurement a surface excess is seen for sorbitol (polar) mixed with PVAc as the surface energy is lowered compare to the one of pure PVAc. This effect is increased upon the addition of carvon or triacetin (non-polars). Surface micro-structures are also evidenced by atomic force microscopy (AFM). Ion beam analysis (Nuclear Reaction Analysis), supplemented by neutron reflectometry can accurately characterize the self-organization of surfactants, oligomers, aromatic molecules in polymer films in order to relate the macroscopic behavior to the length scales that are amenable to simulation. The nuclear reaction analysis (NRA) data for deuterated OA 20% shows the evidence of a surface excess which is enhanced after annealing. The addition of 10% triacetin, as a second migrant, results in the formation of an underlying layer enriched in triacetin below the surface excess of OA. The results show that molecules in polarity mismatch with the matrix tend to segregate to the surface, and this is favored by the addition of a second migrant of the same polarity than the matrix. As studies have been restricted to materials that are model supported films under static conditions in a first step, it is also wished to address the more challenging conditions of materials under controlled stress or strain. To achieve this, a simple rig and PDMS cell have been designed to stretch the material to a defined strain and to probe these mechanical effects by ion beam analysis and atomic force microscopy. This will make a significant step towards exploring the influence of extensional strain on surface segregation, flavor release in cross-linked rubbers.

Keywords: polymers, surface segregation, thin films, molecular migration

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349 The Prediction of Reflection Noise and Its Reduction by Shaped Noise Barriers

Authors: I. L. Kim, J. Y. Lee, A. K. Tekile

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In consequence of the very high urbanization rate of Korea, the number of traffic noise damages in areas congested with population and facilities is steadily increasing. The current environmental noise levels data in major cities of the country show that the noise levels exceed the standards set for both day and night times. This research was about comparative analysis in search for optimal soundproof panel shape and design factor that can minimize sound reflection noise. In addition to the normal flat-type panel shape, the reflection noise reduction of swelling-type, combined swelling and curved-type, and screen-type were evaluated. The noise source model Nord 2000, which often provides abundant information compared to models for the similar purpose, was used in the study to determine the overall noise level. Based on vehicle categorization in Korea, the noise levels for varying frequency from different heights of the sound source (directivity heights of Harmonize model) have been calculated for simulation. Each simulation has been made using the ray-tracing method. The noise level has also been calculated using the noise prediction program called SoundPlan 7.2, for comparison. The noise level prediction was made at 15m (R1), 30 m (R2) and at middle of the road, 2m (R3) receiving the point. By designing the noise barriers by shape and running the prediction program by inserting the noise source on the 2nd lane to the noise barrier side, among the 6 lanes considered, the reflection noise slightly decreased or increased in all noise barriers. At R1, especially in the cases of the screen-type noise barriers, there was no reduction effect predicted in all conditions. However, the swelling-type showed a decrease of 0.7~1.2 dB at R1, performing the best reduction effect among the tested noise barriers. Compared to other forms of noise barriers, the swelling-type was thought to be the most suitable for reducing the reflection noise; however, since a slight increase was predicted at R2, further research based on a more sophisticated categorization of related design factors is necessary. Moreover, as swellings are difficult to produce and the size of the modules are smaller than other panels, it is challenging to install swelling-type noise barriers. If these problems are solved, its applicable region will not be limited to other types of noise barriers. Hence, when a swelling-type noise barrier is installed at a downtown region where the amount of traffic is increasing every day, it will both secure visibility through the transparent walls and diminish any noise pollution due to the reflection. Moreover, when decorated with shapes and design, noise barriers will achieve a visual attraction than a flat-type one and thus will alleviate any psychological hardships related to noise, other than the unique physical soundproofing functions of the soundproof panels.

Keywords: reflection noise, shaped noise barriers, sound proof panel, traffic noise

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348 Pulsed-Wave Doppler Ultrasonographic Assessment of the Maximum Blood Velocity in Common Carotid Artery in Horses after Administration of Ketamine and Acepromazine

Authors: Saman Ahani, Aboozar Dehghan, Roham Vali, Hamid Salehian, Amin Ebrahimi

Abstract:

Pulsed-wave (PW) doppler ultrasonography is a non-invasive, relatively accurate imaging technique that can measure blood speed. The imaging could be obtained via the common carotid artery, as one of the main vessels supplying the blood of vital organs. In horses, factors such as susceptibility to depression of the cardiovascular system and their large muscular mass have rendered them vulnerable to changes in blood speed. One of the most important factors causing blood velocity changes is the administration of anesthetic drugs, including Ketamine and Acepromazine. Thus, in this study, the Pulsed-wave doppler technique was performed to assess the highest blood velocity in the common carotid artery following administration of Ketamine and Acepromazine. Six male and six female healthy Kurdish horses weighing 351 ± 46 kg (mean ± SD) and aged 9.2 ± 1.7 years (mean ± SD) were housed under animal welfare guidelines. After fasting for six hours, the normal blood flow velocity in the common carotid artery was measured using a Pulsed-wave doppler ultrasonography machine (BK Medical, Denmark), and a high-frequency linear transducer (12 MHz) without applying any sedative drugs as a control group. The same procedure was repeated after each individual received the following medications: 1.1, 2.2 mg/kg Ketamine (Pfizer, USA), and 0.5, 1 mg/kg Acepromizine (RACEHORSE MEDS, Ukraine), with an interval of 21 days between the administration of each dose and/or drug. The ultrasonographic study was done five (T5) and fifteen (T15) minutes after injecting each dose intravenously. Lastly, the statistical analysis was performed using SPSS software version 22 for Windows and a P value less than 0.05 was considered to be statistically significant. Five minutes after administration of Ketamine (1.1, 2.2 mg/kg) in both male and female horses, the blood velocity decreased to 38.44, 34.53 cm/s in males, and 39.06, 34.10 cm/s in females in comparison to the control group (39.59 and 40.39 cm/s in males and females respectively) while administration of 0.5 mg/kg Acepromazine led to a significant rise (73.15 and 55.80 cm/s in males and females respectively) (p<0.05). It means that the most drastic change in blood velocity, regardless of gender, refers to the latter dose/drug. In both medications and both genders, the increase in doses led to a decrease in blood velocity compared to the lower dose of the same drug. In all experiments in this study, the blood velocity approached its normal value at T15. In another study comparing the blood velocity changes affected by Ketamine and Acepromazine through femoral arteries, the most drastic changes were attributed to Ketamine; however, in this experiment, the maximum blood velocity was observed following administration of Acepromazine via the common carotid artery. Therefore, further experiments using the same medications are suggested using Pulsed-wave doppler measuring the blood velocity changes in both femoral and common carotid arteries simultaneously.

Keywords: Acepromazine, common carotid artery, horse, ketamine, pulsed-wave doppler ultrasonography

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347 Bi-objective Network Optimization in Disaster Relief Logistics

Authors: Katharina Eberhardt, Florian Klaus Kaiser, Frank Schultmann

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Last-mile distribution is one of the most critical parts of a disaster relief operation. Various uncertainties, such as infrastructure conditions, resource availability, and fluctuating beneficiary demand, render last-mile distribution challenging in disaster relief operations. The need to balance critical performance criteria like response time, meeting demand and cost-effectiveness further complicates the task. The occurrence of disasters cannot be controlled, and the magnitude is often challenging to assess. In summary, these uncertainties create a need for additional flexibility, agility, and preparedness in logistics operations. As a result, strategic planning and efficient network design are critical for an effective and efficient response. Furthermore, the increasing frequency of disasters and the rising cost of logistical operations amplify the need to provide robust and resilient solutions in this area. Therefore, we formulate a scenario-based bi-objective optimization model that integrates pre-positioning, allocation, and distribution of relief supplies extending the general form of a covering location problem. The proposed model aims to minimize underlying logistics costs while maximizing demand coverage. Using a set of disruption scenarios, the model allows decision-makers to identify optimal network solutions to address the risk of disruptions. We provide an empirical case study of the public authorities’ emergency food storage strategy in Germany to illustrate the potential applicability of the model and provide implications for decision-makers in a real-world setting. Also, we conduct a sensitivity analysis focusing on the impact of varying stockpile capacities, single-site outages, and limited transportation capacities on the objective value. The results show that the stockpiling strategy needs to be consistent with the optimal number of depots and inventory based on minimizing costs and maximizing demand satisfaction. The strategy has the potential for optimization, as network coverage is insufficient and relies on very high transportation and personnel capacity levels. As such, the model provides decision support for public authorities to determine an efficient stockpiling strategy and distribution network and provides recommendations for increased resilience. However, certain factors have yet to be considered in this study and should be addressed in future works, such as additional network constraints and heuristic algorithms.

Keywords: humanitarian logistics, bi-objective optimization, pre-positioning, last mile distribution, decision support, disaster relief networks

Procedia PDF Downloads 70