Search results for: future of work
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 19190

Search results for: future of work

920 Nitrate Photoremoval in Water Using Nanocatalysts Based on Ag / Pt over TiO2

Authors: Ana M. Antolín, Sandra Contreras, Francesc Medina, Didier Tichit

Abstract:

Introduction: High levels of nitrates (> 50 ppm NO3-) in drinking water are potentially risky to human health. In the recent years, the trend of nitrate concentration in groundwater is rising in the EU and other countries. Conventional catalytic nitrate reduction processes into N2 and H2O lead to some toxic intermediates and by-products, such as NO2-, NH4+, and NOx gases. Alternatively, photocatalytic nitrate removal using solar irradiation and heterogeneous catalysts is a very promising and ecofriendly technique. It has been scarcely performed and more research on highly efficient catalysts is still needed. In this work, different nanocatalysts supported on Aeroxide Titania P25 (P25) have been prepared varying: 0.5-4 % wt. Ag); Pt (2, 4 % wt.); Pt precursor (H2PtCl6/K2PtCl6); and impregnation order of both metals. Pt was chosen in order to increase the selectivity to N2 and decrease that to NO2-. Catalysts were characterized by nitrogen physisorption, X-Ray diffraction, UV-visible spectroscopy, TEM and X Ray-Photoelectron Spectroscopy. The aim was to determine the influence of the composition and the preparation method of the catalysts on the conversion and selectivity in the nitrate reduction, as well as going through an overall and better understanding of the process. Nanocatalysts synthesis: For the mono and bimetallic catalysts preparation, wise-drop wetness impregnation of the precursors (AgNO3, H2PtCl6, K2PtCl6) followed by a reduction step (NaBH4) was used to obtain the metal colloids. Results and conclusions: Denitration experiments were performed in a 350 mL PTFE batch reactor under inert standard operational conditions, ultraviolet irradiations (λ=254 nm (UV-C); λ=365 nm (UV-A)), and presence/absence of hydrogen gas as a reducing agent, contrary to most studies using oxalic or formic acid. Samples were analyzed by Ionic Chromatography. Blank experiments using respectively P25 (dark conditions), hydrogen only and UV irradiations without hydrogen demonstrated a clear influence of the presence of hydrogen on nitrate reduction. Also, they demonstrated that UV irradiation increased the selectivity to N2. Interestingly, the best activity was obtained under ultraviolet lamps, especially at a closer wavelength to visible light irradiation (λ = 365 nm) and H2. 2% Ag/P25 leaded to the highest NO3- conversion among the monometallic catalysts. However, nitrite quantities have to be diminished. On the other hand, practically no nitrate conversion was observed with the monometallics based on Pt/P25. Therefore, the amount of 2% Ag was chosen for the bimetallic catalysts. Regarding the bimetallic catalysts, it is observed that the metal impregnation order, amount and Pt precursor highly affects the results. Higher selectivity to the desirable N2 gas is obtained when Pt was firstly added, especially with K2PtCl6 as Pt precursor. This suggests that when Pt is secondly added, it covers the Ag particles, which are the most active in this reaction. It could be concluded that Ag allows the nitrate reduction step to nitrite, and Pt the nitrite reduction step toward the desirable N2 gas.

Keywords: heterogeneous catalysis, hydrogenation, nanocatalyst, nitrate removal, photocatalysis

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919 Computational Fluid Dynamics (CFD) Calculations of the Wind Turbine with an Adjustable Working Surface

Authors: Zdzislaw Kaminski, Zbigniew Czyz, Krzysztof Skiba

Abstract:

This paper discusses the CFD simulation of a flow around a rotor of a Vertical Axis Wind Turbine. Numerical simulation, unlike experiments, enables us to validate project assumptions when it is designed and avoid a costly preparation of a model or a prototype for a bench test. CFD simulation enables us to compare characteristics of aerodynamic forces acting on rotor working surfaces and define operational parameters like torque or power generated by a turbine assembly. This research focused on the rotor with the blades capable of modifying their working surfaces, i.e. absorbing wind kinetic energy. The operation of this rotor is based on adjusting angular aperture α of the top and bottom parts of the blades mounted on an axis. If this angular aperture α increases, the working surface which absorbs wind kinetic energy also increases. The operation of turbines is characterized by parameters like the angular aperture of blades, power, torque, speed for a given wind speed. These parameters have an impact on the efficiency of assemblies. The distribution of forces acting on the working surfaces in our turbine changes according to the angular velocity of the rotor. Moreover, the resultant force from the force acting on an advancing blade and retreating blade should be as high as possible. This paper is part of the research to improve an efficiency of a rotor assembly. Therefore, using simulation, the courses of the above parameters were studied in three full rotations individually for each of the blades for three angular apertures of blade working surfaces, i.e. 30 °, 60 °, 90 °, at three wind speeds, i.e. 4 m / s, 6 m / s, 8 m / s and rotor speeds ranging from 100 to 500 rpm. Finally, there were created the characteristics of torque coefficients and power as a function of time for each blade separately and for the entire rotor. Accordingly, the correlation between the turbine rotor power as a function of wind speed for varied values of rotor rotational speed. By processing this data, the correlation between the power of the turbine rotor and its rotational speed for each of the angular aperture of the working surfaces was specified. Finally, the optimal values, i.e. of the highest output power for given wind speeds were read. The research results in receiving the basic characteristics of turbine rotor power as a function of wind speed for the three angular apertures of the blades. Given the nature of rotor operation, the growth in the output turbine can be estimated if angular aperture of the blades increases. The controlled adjustment of angle α enables a smooth adjustment of power generated by a turbine rotor. If wind speed is significant, this type of adjustment enables this output power to remain at the same level (by reducing angle α) with no risk of damaging a construction. This work has been financed by the Polish Ministry of Science and Higher Education.

Keywords: computational fluid dynamics, numerical analysis, renewable energy, wind turbine

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918 Environmental and Formal Conditions for the Development of Blue-green Infrastructure (BGI) in the Cities of Central Europe on the Example of Poland

Authors: Magdalena Biela, Marta Weber-Siwirska, Edyta Sierka

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The current noticed trend in Central European countries, as in other regions of the world, is for people to migrate to cities. As a result, the urban population is to have reached 70% of the total by 2050. Due to this tendency, as well as taking high real estate prices and limited reserves of city green areas into consideration, the greenery and agricultural soil adjacent to cities is are to be devoted to housing projects, while city centres are expected to undergo partial depopulation. Urban heat islands and phenomena such as torrential rains may cause serious damage. They may even endanger the very life and health of the inhabitants. Due to these tangible effects of climate change, residents expect that local government takes action to develop green infrastructure (GI). The main purpose of our research has been to assess the degree of readiness on the part of the local government in Poland to develop BGI. A questionnaire using the CAWI method was prepared, and a survey was carried out. The target group were town hall employees in all 380 powiat cities and towns (380 county centres) in Poland. The form contained 14 questions covering, among others, actions taken to support the development of GI and ways of motivating residents to take such actions. 224 respondents replied to the questions. The results of the research show that 52% of the cities/towns have taken or intend to take measures to favour the development of green spaces. Currently, the installation of green roofs and living walls is are only carried out by 6 Polish cities, and a few more are at the stage of preparing appropriate regulations. The problem of rainwater retention is much more widespread. Among the municipalities declaring any activities for the benefit of GI, approximately 42% have decided to work on this problem. Over 19% of the respondents are planning an increase in the surface occupied by green areas, 14% - the installation of green roofs, and 12% - redevelopment of city greenery. It is optimistic that 67% of the respondents are willing to acquire knowledge about BGI by means of taking part in educational activities both at the national and international levels. There are many ways to help GI development. The most common type of support in the cities and towns surveyed is co-financing (35%), followed by full financing of projects (11%). About 15% of the cities declare only advisory support. Thus, the problem of GI in Central European cities is at the stage of initial development and requires advanced measures and implementation of both proven solutions applied in other European and world countries using the concept of Nature-based Solutions.

Keywords: city/town, blue-green infrastructure, green roofs, climate change adaptation

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917 Development of Loop Mediated Isothermal Amplification (Lamp) Assay for the Diagnosis of Ovine Theileriosis

Authors: Muhammad Fiaz Qamar, Uzma Mehreen, Muhammad Arfan Zaman, Kazim Ali

Abstract:

Ovine Theileriosis is a world-wide concern, especially in tropical and subtropical areas, due to having tick abundance that has received less awareness in different developed and developing areas due to less worth of sheep, low to the middle level of infection in different small ruminants herd. Across Asia, the prevalence reports have been conducted to provide equivalent calculation of flock and animal level prevalence of Theileriosisin animals. It is a challenge for veterinarians to timely diagnosis & control of Theileriosis and famers because of the nature of the organism and inadequacy of restricted plans to control. All most work is based upon the development of such a technique which should be farmer-friendly, less expensive, and easy to perform into the field. By the timely diagnosis of this disease will decrease the irrational use of the drugs, and other plan was to determine the prevalence of Theileriosis in District Jhang by using the conventional method, PCR and qPCR, and LAMP. We quantify the molecular epidemiology of T.lestoquardiin sheep from Jhang districts, Punjab, Pakistan. In this study, we concluded that the overall prevalence of Theileriosis was (32/350*100= 9.1%) in sheep by using Giemsa staining technique, whereas (48/350*100= 13%) is observed by using PCR technique (56/350*100=16%) in qPCR and the LAMP technique have shown up to this much prevalence percentage (60/350*100= 17.1%). The specificity and sensitivity also calculated in comparison with the PCR and LAMP technique. Means more positive results have been shown when the diagnosis has been done with the help of LAMP. And there is little bit of difference between the positive results of PCR and qPCR, and the least positive animals was by using Giemsa staining technique/conventional method. If we talk about the specificity and sensitivity of the LAMP as compared to PCR, The cross tabulation shows that the results of sensitivity of LAMP counted was 94.4%, and specificity of LAMP counted was 78%. Advances in scientific field must be upon reality based ideas which can lessen the gaps and hurdles in the way of scientific research; the lamp is one of such techniques which have done wonders in adding value and helping human at large. It is such a great biological diagnostic tools and has helped a lot in the proper diagnosis and treatment of certain diseases. Other methods for diagnosis, such as culture techniques and serological techniques, have exposed humans with great danger. However, with the help of molecular diagnostic technique like LAMP, exposure to such pathogens is being avoided in the current era Most prompt and tentative diagnosis can be made using LAMP. Other techniques like PCR has many disadvantages when compared to LAMP as PCR is a relatively expensive, time consuming, and very complicated procedure while LAMP is relatively cheap, easy to perform, less time consuming, and more accurate. LAMP technique has removed hurdles in the way of scientific research and molecular diagnostics, making it approachable to poor and developing countries.

Keywords: distribution, thelaria, LAMP, primer sequences, PCR

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916 Garnet-based Bilayer Hybrid Solid Electrolyte for High-Voltage Cathode Material Modified with Composite Interface Enabler on Lithium-Metal Batteries

Authors: Kumlachew Zelalem Walle, Chun-Chen Yang

Abstract:

Solid-state lithium metal batteries (SSLMBs) are considered promising candidates for next-generation energy storage devices due to their superior energy density and excellent safety. However, recent findings have shown that the formation of lithium (Li) dendrites in SSLMBs still exhibits a terrible growth ability, which makes the development of SSLMBs have to face the challenges posed by the Li dendrite problem. In this work, an inorganic/organic mixture coating material (g-C3N4/ZIF-8/PVDF) was used to modify the surface of lithium metal anode (LMA). Then the modified LMA (denoted as g-C₃N₄@Li) was assembled with lithium nafion (LiNf) coated commercial NCM811 (LiNf@NCM811) using a bilayer hybrid solid electrolyte (Bi-HSE) that incorporated 20 wt.% (vs. polymer) LiNf coated Li6.05Ga0.25La3Zr2O11.8F0.2 ([email protected]) filler faced to the positive electrode and the other layer with 80 wt.% (vs. polymer) filler content faced to the g-C₃N₄@Li. The garnet-type Li6.05Ga0.25La3Zr2O11.8F0.2 (LG0.25LZOF) solid electrolyte was prepared via co-precipitation reaction process from Taylor flow reactor and modified using lithium nafion (LiNf), a Li-ion conducting polymer. The Bi-HSE exhibited high ionic conductivity of 6.8  10–4 S cm–1 at room temperature, and a wide electrochemical window (0–5.0 V vs. Li/Li+). The coin cell was charged between 2.8 to 4.5 V at 0.2C and delivered an initial specific discharge capacity of 194.3 mAh g–1 and after 100 cycles it maintained 81.8% of its initial capacity at room temperature. The presence of a nano-sheet g-C3N4/ZIF-8/PVDF as a composite coating material on the LMA surface suppress the dendrite growth and enhance the compatibility as well as the interfacial contact between anode/electrolyte membrane. The g-C3N4@Li symmetrical cells incorporating this hybrid electrolyte possessed excellent interfacial stability over 1000 h at 0.1 mA cm–2 and a high critical current density (1 mA cm–2). Moreover, the in-situ formation of Li3N on the solid electrolyte interface (SEI) layer as depicted from the XPS result also improves the ionic conductivity and interface contact during the charge/discharge process. Therefore, these novel multi-layered fabrication strategies of hybrid/composite solid electrolyte membranes and modification of the LMA surface using mixed coating materials have potential applications in the preparation of highly safe high-voltage cathodes for SSLMBs.

Keywords: high-voltage cathodes, hybrid solid electrolytes, garnet, graphitic-carbon nitride (g-C3N4), ZIF-8 MOF

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915 Capital Accumulation and Unemployment in Namibia, Nigeria and South Africa

Authors: Abubakar Dikko

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The research investigates the causes of unemployment in Namibia, Nigeria and South Africa, and the role of Capital Accumulation in reducing the unemployment profile of these economies as proposed by the post-Keynesian economics. This is conducted through extensive review of literature on the NAIRU models and focused on the post-Keynesian view of unemployment within the NAIRU framework. The NAIRU (non-accelerating inflation rate of unemployment) model has become a dominant framework used in macroeconomic analysis of unemployment. The study views the post-Keynesian economics arguments that capital accumulation is a major determinant of unemployment. Unemployment remains the fundamental socio-economic challenge facing African economies. It has been a burden to citizens of those economies. Namibia, Nigeria and South Africa are great African nations battling with high unemployment rates. In 2013, the countries recorded high unemployment rates of 16.9%, 23.9% and 24.9% respectively. Most of the unemployed in these economies comprises of youth. Roughly about 40% working age South Africans has jobs, whereas in Nigeria and Namibia is less than that. Unemployment in Africa has wide implications on households which has led to extensive poverty and inequality, and created a rampant criminality. Recently in South Africa there has been a case of xenophobic attacks which were caused by the citizens of the country as a result of unemployment. The high unemployment rate in the country led the citizens to chase away foreigners in the country claiming that they have taken away their jobs. The study proposes that there is a strong relationship between capital accumulation and unemployment in Namibia, Nigeria and South Africa, and capital accumulation is responsible for high unemployment rates in these countries. For the economies to achieve steady state level of employment and satisfactory level of economic growth and development there is need for capital accumulation to take place. The countries in the study have been selected after a critical research and investigations. They are selected based on the following criteria; African economies with high unemployment rates above 15% and have about 40% of their workforce unemployed. This level of unemployment is the critical level of unemployment in Africa as expressed by International Labour Organization (ILO). The African countries with low level of capital accumulation. Adequate statistical measures have been employed using a time-series analysis in the study and the results revealed that capital accumulation is the main driver of unemployment performance in the chosen African countries. An increase in the accumulation of capital causes unemployment to reduce significantly. The results of the research work will be useful and relevant to federal governments and ministries, departments and agencies (MDAs) of Namibia, Nigeria and South Africa to resolve the issue of high and persistent unemployment rates in their economies which are great burden that slows growth and development of developing economies. Also, the result can be useful to World Bank, African Development Bank and International Labour Organization (ILO) in their further research and studies on how to tackle unemployment in developing and emerging economies.

Keywords: capital accumulation, unemployment, NAIRU, Post-Keynesian economics

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914 Whistleblowing a Contemporary Topic Concerning Businesses

Authors: Andreas Kapardis, Maria Krambia-Kapardis, Sofia Michaelides-Mateou

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Corruption and economic crime is a serious problem affecting the sustainability of businesses in the 21st century. Nowadays, many corruption or fraud cases come to light thanks to whistleblowers. This article will first discuss the concept of whistleblowing as well as some relevant legislation enacted around the world. Secondly, it will discuss the findings of a survey of whistleblowers or could-have-been whistleblowers. Finally, suggestions for the development of a comprehensive whistleblowing framework will be considered. Whistleblowing can be described as expressing a concern about a wrongdoing within an organization, such as a corporation, an association, an institution or a union. Such concern must be in the public interest and in good faith and should relate to the cover up of matters that could potentially result in a miscarriage of justice, a crime, criminal offence and threats to health and safety. Whistleblowing has proven to be an effective anti-corruption mechanism and a powerful tool that helps deterring fraud, violations, and malpractices within organizations, corporations and the public sector. Research in the field of whistleblowing has concentrated on the reasons for whistleblowing and financial bounties; the effectiveness of whistleblowing; whistleblowing being a prosocial behavior with a psychological perspective and consequences; as a tool in protecting shareholders, saving lives and billions of dollars of public funds. Whilst, no other study of whistleblowing has been carried out on whistleblowers or intended whistleblowers. The study reported in the current paper analyses the findings of 74 whistleblowers or intended whistleblowers, the reasons behind their decision to blow the whistle, or not to proceed to blow the whistle and any regrets they may have had. In addition a profile of a whistleblower is developed concerning their age, gender, marital and family status and position in an organization. Lessons learned from the intended whistleblowers and in response to the questions if they would be willing to blow the whistle again show that enacting legislation to protect the whistleblower is not enough. Similarly, rewarding the whistleblower does not appear to provide the whistleblower with an incentive since the majority noted that “work ethics is more important than financial rewards”. We recommend the development of a comprehensive and holistic framework for the protection of the whistleblower and to ensure that remedial actions are immediately taken once a whistleblower comes forward. The suggested framework comprises (a) hard legislation in ensuring the whistleblowers follow certain principles when blowing the whistle and, in return, are protected for a period of 5 years from being fired, dismissed, bullied, harassed; (b) soft legislation in establishing an agency to firstly ensure psychological and legal advice is provided to the whistleblowers and secondly any required remedial action is immediately taken to avert the undesirable events reported by a whistleblower from occurring and, finally; (c) mechanisms to ensure the coordination of actions taken.

Keywords: whistleblowing, business ethics, legislation, business

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913 Stability of a Biofilm Reactor Able to Degrade a Mixture of the Organochlorine Herbicides Atrazine, Simazine, Diuron and 2,4-Dichlorophenoxyacetic Acid to Changes in the Composition of the Supply Medium

Authors: I. Nava-Arenas, N. Ruiz-Ordaz, C. J. Galindez-Mayer, M. L. Luna-Guido, S. L. Ruiz-López, A. Cabrera-Orozco, D. Nava-Arenas

Abstract:

Among the most important herbicides, the organochlorine compounds are of considerable interest due to their recalcitrance to the chemical, biological, and photolytic degradation, their persistence in the environment, their mobility, and their bioacummulation. The most widely used herbicides in North America are primarily 2,4-dichlorophenoxyacetic acid (2,4-D), the triazines (atrazine and simazine), and to a lesser extent diuron. The contamination of soils and water bodies frequently occurs by mixtures of these xenobiotics. For this reason, in this work, the operational stability to changes in the composition of the medium supplied to an aerobic biofilm reactor was studied. The reactor was packed with fragments of volcanic rock that retained a complex microbial film, able to degrade a mixture of organochlorine herbicides atrazine, simazine, diuron and 2,4-D, and whose members have microbial genes encoding the main catabolic enzymes atzABCD, tfdACD and puhB. To acclimate the attached microbial community, the biofilm reactor was fed continuously with a mineral minimal medium containing the herbicides (in mg•L-1): diuron, 20.4; atrazine, 14.2, simazine, 11.4, and 2,4-D, 59.7, as carbon and nitrogen sources. Throughout the bioprocess, removal efficiencies of 92-100% for herbicides, 78-90% for COD, 92-96% for TOC and 61-83% for dehalogenation were reached. In the microbial community, the genes encoding catabolic enzymes of different herbicides tfdACD, puhB and, occasionally, the genes atzA and atzC were detected. After the acclimatization, the triazine herbicides were eliminated from the mixture formulation. Volumetric loading rates of the mixture 2,4-D and diuron were continuously supplied to the reactor (1.9-21.5 mg herbicides •L-1 •h-1). Along the bioprocess, the removal efficiencies obtained were 86-100% for the mixture of herbicides, 63-94% for for COD, 90-100% for COT, and dehalogenation values of 63-100%. It was also observed that the genes encoding the enzymes in the catabolism of both herbicides, tfdACD and puhB, were consistently detected; and, occasionally, the atzA and atzC. Subsequently, the triazine herbicide atrazine and simazine were restored to the medium supply. Different volumetric charges of this mixture were continuously fed to the reactor (2.9 to 12.6 mg herbicides •L-1 •h-1). During this new treatment process, removal efficiencies of 65-95% for the mixture of herbicides, 63-92% for COD, 66-89% for TOC and 73-94% of dehalogenation were observed. In this last case, the genes tfdACD, puhB and atzABC encoding for the enzymes involved in the catabolism of the distinct herbicides were consistently detected. The atzD gene, encoding the cyanuric hydrolase enzyme, could not be detected, though it was determined that there was partial degradation of cyanuric acid. In general, the community in the biofilm reactor showed some catabolic stability, adapting to changes in loading rates and composition of the mixture of herbicides, and preserving their ability to degrade the four herbicides tested; although, there was a significant delay in the response time to recover to degradation of the herbicides.

Keywords: biodegradation, biofilm reactor, microbial community, organochlorine herbicides

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912 Bedouin of Silicon Wadi: A Case Study Analysis of the Multi-Level Perspectives and Factors Affecting Bedouin Entrepreneurialism as Obstacles to Entry into the Israeli High-Tech Industry

Authors: Frazer G. Thompson

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Israel is a nation of cultural and historical diversity, yet the success factors for a modern Bedouin-Arab high-tech entrepreneur seem to be different from those of other Jewish-Israeli citizens. The purpose of this descriptive narrative case study is to explore how an Arab-Israeli all Negev-Bedouin technology company has succeeded in the Israeli high-tech industry by utilizing technology and engineering career opportunities available to Bedouin youth for ‘Sadel Tech,’ at Be’er-Sheva, the Negev, Israel. Methods: The strategy of inquiry seeks to explore real-life contextual understandings, multi-level perspectives, and the cultural influences of personal, community, educational, and entrepreneurial factors. The research methodology includes in-depth one-on-one interviews, focus group sessions, and overt observation to explore the meaning and understanding of the constructs toward determining the effect all or a few of the elements may have on the overall success factors of the company. Results: Study results indicate that the state-run educational system in Israel fails to adequately integrate important aspects of Bedouin culture into the learning environment. However, Bedouin entrepreneurs are finding ways to compensate for these inadequacies by utilizing non-traditional methods of teaching, learning, and doing business. Government incentives for Bedouin start-ups are also recognized as contributors. Employees of Sadel live and work in the Negev, the Gaza Strip, and the West Bank, further informing the study that the traditions of tribal etiquette continue to contribute to modern Bedouin-Arab business culture. Conclusion: Bedouin's business success in Israel is a multi-dimensional concept. While cultural acumen plays a prominent and unique role for both Arab-Israelis and Jewish-Israelis in economic and entrepreneurial pursuits, the marginalization of the Bedouin continues to contribute to the lack of educational and professional opportunities for Bedouin in Israel. Although recognized as important at the government level, programs necessary to implement the infrastructure required to support Bedouin entrepreneurship in Israel remain infantile. The Israeli Government is providing opportunities through grants and other incentives for Bedouin entrepreneurial start-ups, indicating that Israel has recognized the impact of this growing demographic. However, although many Bedouin graduates from University each year with advanced degrees, opportunities for Bedouin within the Israeli high-tech sector remain scarce.

Keywords: Bedouin education, Bedouin entrepreneur, economic anthropology, ethnic business opportunities, Israeli tech, Silicon Wadi

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911 Convective Boiling of CO₂/R744 in Macro and Micro-Channels

Authors: Adonis Menezes, J. C. Passos

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The current panorama of technology in heat transfer and the scarcity of information about the convective boiling of CO₂ and hydrocarbon in small diameter channels motivated the development of this work. Among non-halogenated refrigerants, CO₂/ R744 has distinct thermodynamic properties compared to other fluids. The R744 presents significant differences in operating pressures and temperatures, operating at higher values compared to other refrigerants, and this represents a challenge for the design of new evaporators, as the original systems must normally be resized to meet the specific characteristics of the R744, which creates the need for a new design and optimization criteria. To carry out the convective boiling tests of CO₂, an experimental apparatus capable of storing (m= 10kg) of saturated CO₂ at (T = -30 ° C) in an accumulator tank was used, later this fluid was pumped using a positive displacement pump with three pistons, and the outlet pressure was controlled and could reach up to (P = 110bar). This high-pressure saturated fluid passed through a Coriolis type flow meter, and the mass velocities varied between (G = 20 kg/m².s) up to (G = 1000 kg/m².s). After that, the fluid was sent to the first test section of circular cross-section in diameter (D = 4.57mm), where the inlet and outlet temperatures and pressures, were controlled and the heating was promoted by the Joule effect using a source of direct current with a maximum heat flow of (q = 100 kW/m²). The second test section used a cross-section with multi-channels (seven parallel channels) with a square cross-section of (D = 2mm) each; this second test section has also control of temperature and pressure at the inlet and outlet as well as for heating a direct current source was used, with a maximum heat flow of (q = 20 kW/m²). The fluid in a biphasic situation was directed to a parallel plate heat exchanger so that it returns to the liquid state, thus being able to return to the accumulator tank, continuing the cycle. The multi-channel test section has a viewing section; a high-speed CMOS camera was used for image acquisition, where it was possible to view the flow patterns. The experiments carried out and presented in this report were conducted in a rigorous manner, enabling the development of a database on the convective boiling of the R744 in macro and micro channels. The analysis prioritized the processes from the beginning of the convective boiling until the drying of the wall in a subcritical regime. The R744 resurfaces as an excellent alternative to chlorofluorocarbon refrigerants due to its negligible ODP (Ozone Depletion Potential) and GWP (Global Warming Potential) rates, among other advantages. The results found in the experimental tests were very promising for the use of CO₂ in micro-channels in convective boiling and served as a basis for determining the flow pattern map and correlation for determining the heat transfer coefficient in the convective boiling of CO₂.

Keywords: convective boiling, CO₂/R744, macro-channels, micro-channels

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910 Identifying the Risks on Philippines’ Pre- and Post-Disaster Media Communication on Natural Hazards

Authors: Neyzielle Ronnicque Cadiz

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The Philippine is a hotbed of disasters and is a locus of natural hazards. With an average of 20 typhoons entering the Philippine Area of Responsibility (PAR) each year, seven to eight (7-8) of which makes landfall. The country rather inevitably suffers from climate-related calamities. With this vulnerability to natural hazards, the relevant hazard-related issues that come along with the potential threat and occurrence of a disaster oftentimes garners lesser media attention than when a disaster actually occurred. Post-disaster news and events flood the content of news networks primarily focusing on, but not limited to, the efforts of the national government in resolving post-disaster displacement, and all the more on the community leaders’ incompetence in disaster mitigation-- even though the University of the Philippines’ NOAH Center work hand in hand with different stakeholders for disaster mitigation communication efforts. Disaster risk communication is actually a perennial dilemma. There are so many efforts to reach the grassroots level but emergency and disaster preparedness messages inevitably fall short.. The Philippines is very vulnerable to hazards risk and disasters but social media posts and communication efforts mostly go unnoticed, if not argued upon. This study illustrates the outcomes of a research focusing on the print, broadcast, and social media’s role on disaster communication involving the natural catastrophic events that took place in the Philippines from 2009 to present. Considering the country’s state of development, this study looks on the rapid and reliable communication between the government, and the relief/rescue workers in the affected regions; and how the media portrays these efforts effectively. Learning from the disasters that have occurred in the Philippines over the past decade, effective communication can ensure that any efforts to prepare and respond to disasters can make a significant difference. It can potentially either break or save lives. Recognizing the role of communications is not only in improving the coordination of vital services for post disaster; organizations gave priority in reexamining disaster preparedness mechanisms through the Communication with Communities (CwC) programs. This study, however, looks at the CwC efforts of the Philippine media platforms. CwC, if properly utilized by the media, is an essential tool in ensuring accountability and transparency which require effective exchange of information between disasters and survivors and responders. However, in this study, it shows that the perennial dilemma of the Philippine media is that the Disaster Risk Reduction and Management (DRRM) efforts of the country lie in the clouded judgment of political aims. This kind of habit is a multiplier of the country’s risk and insecurity. Sometimes the efforts in urging the public to take action seem useless because the challenge lies on how to achieve social, economic, and political unity using the tri-media platform.

Keywords: Philippines at risk, pre/post disaster communication, tri-media platform, UP NOAH

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909 Offshore Wind Assessment and Analysis for South Western Mediterranean Sea

Authors: Abdallah Touaibia, Nachida Kasbadji Merzouk, Mustapha Merzouk, Ryma Belarbi

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accuracy assessment and a better understand of the wind resource distribution are the most important tasks for decision making before installing wind energy operating systems in a given region, there where our interest come to the Algerian coastline and its Mediterranean sea area. Despite its large coastline overlooking the border of Mediterranean Sea, there is still no strategy encouraging the development of offshore wind farms in Algerian waters. The present work aims to estimate the offshore wind fields for the Algerian Mediterranean Sea based on wind data measurements ranging from 1995 to 2018 provided of 24 years of measurement by seven observation stations focusing on three coastline cities in Algeria under a different measurement time step recorded from 30 min, 60 min, and 180 min variate from one to each other, two stations in Spain, two other ones in Italy and three in the coast of Algeria from the east Annaba, at the center Algiers, and to Oran taken place at the west of it. The idea behind consists to have multiple measurement points that helping to characterize this area in terms of wind potential by the use of interpolation method of their average wind speed values between these available data to achieve the approximate values of others locations where aren’t any available measurement because of the difficulties against the implementation of masts within the deep depth water. This study is organized as follow: first, a brief description of the studied area and its climatic characteristics were done. After that, the statistical properties of the recorded data were checked by evaluating wind histograms, direction roses, and average speeds using MatLab programs. Finally, ArcGIS and MapInfo soft-wares were used to establish offshore wind maps for better understanding the wind resource distribution, as well as to identify windy sites for wind farm installation and power management. The study pointed out that Cap Carbonara is the windiest site with an average wind speed of 7.26 m/s at 10 m, inducing a power density of 902 W/m², then the site of Cap Caccia with 4.88 m/s inducing a power density of 282 W/m². The average wind speed of 4.83 m/s is occurred for the site of Oran, inducing a power density of 230 W/m². The results indicated also that the dominant wind direction where the frequencies are highest for the site of Cap Carbonara is the West with 34%, an average wind speed of 9.49 m/s, and a power density of 1722 W/m². Then comes the site of Cap Caccia, where the prevailing wind direction is the North-west, about 20% and 5.82 m/s occurring a power density of 452 W/m². The site of Oran comes in third place with the North dominant direction with 32% inducing an average wind speed of 4.59 m/s and power density of 189 W/m². It also shown that the proposed method is either crucial in understanding wind resource distribution for revealing windy sites over a large area and more effective for wind turbines micro-siting.

Keywords: wind ressources, mediterranean sea, offshore, arcGIS, mapInfo, wind maps, wind farms

Procedia PDF Downloads 130
908 Molecular Modeling and Prediction of the Physicochemical Properties of Polyols in Aqueous Solution

Authors: Maria Fontenele, Claude-Gilles Dussap, Vincent Dumouilla, Baptiste Boit

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Roquette Frères is a producer of plant-based ingredients that employs many processes to extract relevant molecules and often transforms them through chemical and physical processes to create desired ingredients with specific functionalities. In this context, Roquette encounters numerous multi-component complex systems in their processes, including fibers, proteins, and carbohydrates, in an aqueous environment. To develop, control, and optimize both new and old processes, Roquette aims to develop new in silico tools. Currently, Roquette uses process modelling tools which include specific thermodynamic models and is willing to develop computational methodologies such as molecular dynamics simulations to gain insights into the complex interactions in such complex media, and especially hydrogen bonding interactions. The issue at hand concerns aqueous mixtures of polyols with high dry matter content. The polyols mannitol and sorbitol molecules are diastereoisomers that have nearly identical chemical structures but very different physicochemical properties: for example, the solubility of sorbitol in water is 2.5 kg/kg of water, while mannitol has a solubility of 0.25 kg/kg of water at 25°C. Therefore, predicting liquid-solid equilibrium properties in this case requires sophisticated solution models that cannot be based solely on chemical group contributions, knowing that for mannitol and sorbitol, the chemical constitutive groups are the same. Recognizing the significance of solvation phenomena in polyols, the GePEB (Chemical Engineering, Applied Thermodynamics, and Biosystems) team at Institut Pascal has developed the COSMO-UCA model, which has the structural advantage of using quantum mechanics tools to predict formation and phase equilibrium properties. In this work, we use molecular dynamics simulations to elucidate the behavior of polyols in aqueous solution. Specifically, we employ simulations to compute essential metrics such as radial distribution functions and hydrogen bond autocorrelation functions. Our findings illuminate a fundamental contrast: sorbitol and mannitol exhibit disparate hydrogen bond lifetimes within aqueous environments. This observation serves as a cornerstone in elucidating the divergent physicochemical properties inherent to each compound, shedding light on the nuanced interplay between their molecular structures and water interactions. We also present a methodology to predict the physicochemical properties of complex solutions, taking as sole input the three-dimensional structure of the molecules in the medium. Finally, by developing knowledge models, we represent some physicochemical properties of aqueous solutions of sorbitol and mannitol.

Keywords: COSMO models, hydrogen bond, molecular dynamics, thermodynamics

Procedia PDF Downloads 23
907 Multiphase Equilibrium Characterization Model For Hydrate-Containing Systems Based On Trust-Region Method Non-Iterative Solving Approach

Authors: Zhuoran Li, Guan Qin

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A robust and efficient compositional equilibrium characterization model for hydrate-containing systems is required, especially for time-critical simulations such as subsea pipeline flow assurance analysis, compositional simulation in hydrate reservoirs etc. A multiphase flash calculation framework, which combines Gibbs energy minimization function and cubic plus association (CPA) EoS, is developed to describe the highly non-ideal phase behavior of hydrate-containing systems. A non-iterative eigenvalue problem-solving approach for the trust-region sub-problem is selected to guarantee efficiency. The developed flash model is based on the state-of-the-art objective function proposed by Michelsen to minimize the Gibbs energy of the multiphase system. It is conceivable that a hydrate-containing system always contains polar components (such as water and hydrate inhibitors), introducing hydrogen bonds to influence phase behavior. Thus, the cubic plus associating (CPA) EoS is utilized to compute the thermodynamic parameters. The solid solution theory proposed by van der Waals and Platteeuw is applied to represent hydrate phase parameters. The trust-region method combined with the trust-region sub-problem non-iterative eigenvalue problem-solving approach is utilized to ensure fast convergence. The developed multiphase flash model's accuracy performance is validated by three available models (one published and two commercial models). Hundreds of published hydrate-containing system equilibrium experimental data are collected to act as the standard group for the accuracy test. The accuracy comparing results show that our model has superior performances over two models and comparable calculation accuracy to CSMGem. Efficiency performance test also has been carried out. Because the trust-region method can determine the optimization step's direction and size simultaneously, fast solution progress can be obtained. The comparison results show that less iteration number is needed to optimize the objective function by utilizing trust-region methods than applying line search methods. The non-iterative eigenvalue problem approach also performs faster computation speed than the conventional iterative solving algorithm for the trust-region sub-problem, further improving the calculation efficiency. A new thermodynamic framework of the multiphase flash model for the hydrate-containing system has been constructed in this work. Sensitive analysis and numerical experiments have been carried out to prove the accuracy and efficiency of this model. Furthermore, based on the current thermodynamic model in the oil and gas industry, implementing this model is simple.

Keywords: equation of state, hydrates, multiphase equilibrium, trust-region method

Procedia PDF Downloads 156
906 Metamorphosis of Caste: An Examination of the Transformation of Caste from a Material to Ideological Phenomenon in Sri Lanka

Authors: Pradeep Peiris, Hasini Lecamwasam

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The fluid, ambiguous, and often elusive existence of caste among the Sinhalese in Sri Lanka has inspired many scholarly endeavours. Originally, Sinhalese caste was organized according to the occupational functions assigned to various groups in society. Hence cultivators came to be known as Goyigama, washers Dobi, drummers Berava, smiths Navandanna and so on. During pre-colonial times the specialized services of various groups were deployed to build water reservoirs, cultivate the land, and/or sustain the Buddhist order by material means. However, as to how and why caste prevails today in Sinhalese society when labour is in ideal terms free to move where it wants, or in other words, occupation is no longer strictly determined or restricted by birth, is a question worth exploring. Hence this paper explores how, and perhaps more interestingly why, when the nexus between traditional occupations and caste status is fast disappearing, caste itself has managed to survive and continues to be salient in politics in Sri Lanka. In answer to this larger question, the paper looks at caste from three perspectives: 1) Buddhism, whose ethical project provides a justification of social stratifications that transcends economic bases 2) Capitalism that has reactivated and reproduced archaic relations in a process of 'accumulation by subordination', not only by reinforcing the marginality of peripheral caste groups, but also by exploiting caste divisions to hinder any realization of class interests and 3) Democracy whose supposed equalizing effect expected through its ‘one man–one vote’ approach has been subverted precisely by itself, whereby the aggregate ultimately comes down to how many such votes each ‘group’ in society has. This study draws from field work carried out in Dedigama (in the District of Kegalle, Central Province) and Kelaniya (in the District of Colombo, Western Province) in Sri Lanka over three years. The choice of field locations was encouraged by the need to capture rural and urban dynamics related to caste since caste is more apparently manifest in rural areas whose material conditions partially warrant its prevalence, whereas in urban areas it exists mostly in the ideological terrain. In building its analysis, the study has employed a combination of objectivist and subjectivist approaches to capture the material and ideological existence of caste and caste politics in Sinhalese society. Therefore, methods such as in-depth interviews, observation, and collection of demographical and interpretive data from secondary sources were used for this study. The paper has been situated in a critical theoretical framework of social inquiry in an attempt to question dominant assumptions regarding such meta-labels as ‘Capitalism’ and ‘Democracy’, and also the supposed emancipatory function of religion (focusing on Buddhism).

Keywords: Buddhism, capitalism, caste, democracy, Sri Lanka

Procedia PDF Downloads 121
905 Influence of Footing Offset over Stability of Geosynthetic Reinforced Soil Abutments with Variable Facing under Lateral Excitation

Authors: Ashutosh Verma, Satyendra MIttal

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The loss of strength at the facing-reinforcement interface brought on by the seasonal thermal expansion/contraction of the bridge deck has been responsible for several geosynthetic reinforced soil abutment failures over the years. This results in excessive settlement below the bridge seat, which results in bridge bumps along the approach road and shortens abutment's design life. There are surely a wide variety of facing configurations available to designers when choosing the sort of facade. These layouts can generally be categorised into three groups: continuous, full height rigid (FHR) and modular (panels/block). The current work aims to experimentally explore the behavior of these three facing categories using 1g physical model testing under serviceable cyclic lateral displacements. With configurable facing arrangements to represent these three facing categories, a field instrumented GRS abutment prototype was modelled into a N scaled down 1g physical model (N = 5) to reproduce field behavior. Peak earth pressure coefficient (K) on the facing and vertical settlement of the footing (s/B) for footing offset (x/H) as 0.1, 0.2, 0.3, 0.4 and 0.5 at 100 cycles have been measured for cyclic lateral displacement of top of facing at loading rate of 1mm/min. Three types of cyclic displacements have been carried out to replicate active condition (CA), passive condition (CP), and active-passive condition (CAP) for each footing offset. The results demonstrated that a significant decrease in the earth pressure over the facing occurs when footing offset increases. It is worth noticing that the highest rate of increment in earth pressure and footing settlement were observed for each facing configuration at the nearest footing offset. Interestingly, for the farthest footing offset, similar responses of each facing type were observed, which indicates that the upon reaching a critical offset point presumably beyond the active region in the backfill, the lateral responses become independent of the stresses from the external footing load. Evidently, the footing load complements the stresses developed due to lateral excitation resulting in significant footing settlements for nearer footing offsets. The modular facing proved inefficient in resisting footing settlement due to significant buckling along the depth of facing. Instead of relative displacement along the depth of facing, continuous facing rotates around the base when it fails, especially for nearer footing offset causing significant depressions in the backfill area surrounding the footing. FHR facing, on the other hand, have been successful in confining the stresses in the soil domain itself reducing the footing settlement. It may be suitably concluded that increasing the footing offset may render stability to the GRS abutment with any facing configuration even for higher cycles of excitation.

Keywords: GRS abutments, 1g physical model, footing offset, cyclic lateral displacement

Procedia PDF Downloads 66
904 In-Situ Formation of Particle Reinforced Aluminium Matrix Composites by Laser Powder Bed Fusion of Fe₂O₃/AlSi12 Powder Mixture Using Consecutive Laser Melting+Remelting Strategy

Authors: Qimin Shi, Yi Sun, Constantinus Politis, Shoufeng Yang

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In-situ preparation of particle-reinforced aluminium matrix composites (PRAMCs) by laser powder bed fusion (LPBF) additive manufacturing is a promising strategy to strengthen traditional Al-based alloys. The laser-driven thermite reaction can be a practical mechanism to in-situ synthesize PRAMCs. However, introducing oxygen elements through adding Fe₂O₃ makes the powder mixture highly sensitive to form porosity and Al₂O₃ film during LPBF, bringing challenges to producing dense Al-based materials. Therefore, this work develops a processing strategy combined with consecutive high-energy laser melting scanning and low-energy laser remelting scanning to prepare PRAMCs from a Fe₂O₃/AlSi12 powder mixture. The powder mixture consists of 5 wt% Fe₂O₃ and the remainder AlSi12 powder. The addition of 5 wt% Fe₂O₃ aims to achieve balanced strength and ductility. A high relative density (98.2 ± 0.55 %) was successfully obtained by optimizing laser melting (Emelting) and laser remelting surface energy density (Eremelting) to Emelting = 35 J/mm² and Eremelting = 5 J/mm². Results further reveal the necessity of increasing Emelting, to improve metal liquid’s spreading/wetting by breaking up the Al₂O₃ films surrounding the molten pools; however, the high-energy laser melting produced much porosity, including H₂₋, O₂₋ and keyhole-induced pores. The subsequent low-energy laser remelting could close the resulting internal pores, backfill open gaps and smoothen solidified surfaces. As a result, the material was densified by repeating laser melting and laser remelting layer by layer. Although with two-times laser scanning, the microstructure still shows fine cellular Si networks with Al grains inside (grain size of about 370 nm) and in-situ nano-precipitates (Al₂O₃, Si, and Al-Fe(-Si) intermetallics). Finally, the fine microstructure, nano-structured dispersion strengthening, and high-level densification strengthened the in-situ PRAMCs, reaching yield strength of 426 ± 4 MPa and tensile strength of 473 ± 6 MPa. Furthermore, the results can expect to provide valuable information to process other powder mixtures with severe porosity/oxide-film formation potential, considering the evidenced contribution of laser melting/remelting strategy to densify material and obtain good mechanical properties during LPBF.

Keywords: densification, laser powder bed fusion, metal matrix composites, microstructures, mechanical properties

Procedia PDF Downloads 142
903 A Public Health Perspective on Deradicalisation: Re-Conceptualising Deradicalisation Approaches

Authors: Erin Lawlor

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In 2008 Time magazine named terrorist rehabilitation as one of the best ideas of the year. The term deradicalisation has become synonymous with rehabilitation within security discourse. The allure for a “quick fix” when managing terrorist populations (particularly within prisons) has led to a focus on prescriptive programmes where there is a distinct lack of exploration into the drivers for a person to disengage or deradicalise from violence. It has been argued that to tackle a snowballing issue that interventions have moved too quickly for both theory development and methodological structure. This overly quick acceptance of a term that lacks rigorous testing, measuring, and monitoring means that there is distinct lack of evidence base for deradicalisation being a genuine process/phenomenon, leading to academics retrospectively attempting to design frameworks and interventions around a concept that is not truly understood. The UK Home Office has openly acknowledged the lack of empirical data on this subject. This lack of evidence has a direct impact on policy and intervention development. Extremism and deradicalisation are issues that affect public health outcomes on a global scale, to the point that terrorism has now been added to the list of causes of trauma, both in the direct form of being victim of an attack but also the indirect context of witnesses, children and ordinary citizens who live in daily fear. This study critiques current deradicalisation discourses to establish whether public health approaches offer opportunities for development. The research begins by exploring the theoretical constructs of both what deradicalisation, and public health issues are. Questioning: What does deradicalisation involve? Is there an evidential base on which deradicalisation theory has established itself? What theory are public health interventions devised from? What does success look like in both fields? From establishing this base, current deradicalisation practices will then be explored through examples of work already being carried out. Critiques can be broken into discussion points of: Language, the difficulties with conducting empirical studies and the issues around outcome measurements that deradicalisation interventions face. This study argues that a public health approach towards deradicalisation offers the opportunity to attempt to bring clarity to the definitions of radicalisation, identify what could be modified through intervention and offer insights into the evaluation of interventions. As opposed to simply focusing on an element of deradicalisation and analysing that in isolation, a public health approach allows for what the literature has pointed out is missing, a comprehensive analysis of current interventions and information on creating efficacy monitoring systems. Interventions, policies, guidance, and practices in both the UK and Australia will be compared and contrasted, due to the joint nature of this research between Sheffield Hallam University and La Trobe, Melbourne.

Keywords: radicalisation, deradicalisation, violent extremism, public health

Procedia PDF Downloads 56
902 Cycle-Oriented Building Components and Constructions Made from Paper Materials

Authors: Rebecca Bach, Evgenia Kanli, Nihat Kiziltoprak, Linda Hildebrand, Ulrich Knaack, Jens Schneider

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The building industry has a high demand for resources and at the same time is responsible for a significant amount of waste created worldwide. Today's building components need to contribute to the protection of natural resources without creating waste. This is defined in the product development phase and impacts the product’s degree of being cycle-oriented. Paper-based materials show advantage due to their renewable origin and their ability to incorporate different functions. Besides the ecological aspects like renewable origin and recyclability the main advantages of paper materials are its light-weight but stiff structure, the optimized production processes and good insulation values. The main deficits from building technology’s perspective are the material's vulnerability to humidity and water as well as inflammability. On material level, those problems can be solved by coatings or through material modification. On construction level intelligent setup and layering of a building component can improve and also solve these issues. The target of the present work is to provide an overview of developed building components and construction typologies mainly made from paper materials. The research is structured in four parts: (1) functions and requirements, (2) preselection of paper-based materials, (3) development of building components and (4) evaluation. As part of the research methodology at first the needs of the building sector are analyzed with the aim to define the main areas of application and consequently the requirements. Various paper materials are tested in order to identify to what extent the requirements are satisfied and determine potential optimizations or modifications, also in combination with other construction materials. By making use of the material’s potentials and solving the deficits on material and on construction level, building components and construction typologies are developed. The evaluation and the calculation of the structural mechanics and structural principals will show that different construction typologies can be derived. Profiles like paper tubes can be used at best for skeleton constructions. Massive structures on the other hand can be formed by plate-shaped elements like solid board or honeycomb. For insulation purposes corrugated cardboard or cellulose flakes have the best properties, while layered solid board can be applied to prevent inner condensation. Enhancing these properties by material combinations for instance with mineral coatings functional constructions mainly out of paper materials were developed. In summary paper materials offer a huge variety of possible applications in the building sector. By these studies a general base of knowledge about how to build with paper was developed and is to be reinforced by further research.

Keywords: construction typologies, cycle-oriented construction, innovative building material, paper materials, renewable resources

Procedia PDF Downloads 263
901 Deep Convolutional Neural Network for Detection of Microaneurysms in Retinal Fundus Images at Early Stage

Authors: Goutam Kumar Ghorai, Sandip Sadhukhan, Arpita Sarkar, Debprasad Sinha, G. Sarkar, Ashis K. Dhara

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Diabetes mellitus is one of the most common chronic diseases in all countries and continues to increase in numbers significantly. Diabetic retinopathy (DR) is damage to the retina that occurs with long-term diabetes. DR is a major cause of blindness in the Indian population. Therefore, its early diagnosis is of utmost importance towards preventing progression towards imminent irreversible loss of vision, particularly in the huge population across rural India. The barriers to eye examination of all diabetic patients are socioeconomic factors, lack of referrals, poor access to the healthcare system, lack of knowledge, insufficient number of ophthalmologists, and lack of networking between physicians, diabetologists and ophthalmologists. A few diabetic patients often visit a healthcare facility for their general checkup, but their eye condition remains largely undetected until the patient is symptomatic. This work aims to focus on the design and development of a fully automated intelligent decision system for screening retinal fundus images towards detection of the pathophysiology caused by microaneurysm in the early stage of the diseases. Automated detection of microaneurysm is a challenging problem due to the variation in color and the variation introduced by the field of view, inhomogeneous illumination, and pathological abnormalities. We have developed aconvolutional neural network for efficient detection of microaneurysm. A loss function is also developed to handle severe class imbalance due to very small size of microaneurysms compared to background. The network is able to locate the salient region containing microaneurysms in case of noisy images captured by non-mydriatic cameras. The ground truth of microaneurysms is created by expert ophthalmologists for MESSIDOR database as well as private database, collected from Indian patients. The network is trained from scratch using the fundus images of MESSIDOR database. The proposed method is evaluated on DIARETDB1 and the private database. The method is successful in detection of microaneurysms for dilated and non-dilated types of fundus images acquired from different medical centres. The proposed algorithm could be used for development of AI based affordable and accessible system, to provide service at grass root-level primary healthcare units spread across the country to cater to the need of the rural people unaware of the severe impact of DR.

Keywords: retinal fundus image, deep convolutional neural network, early detection of microaneurysms, screening of diabetic retinopathy

Procedia PDF Downloads 126
900 Attachment Theory and Quality of Life: Grief Education and Training

Authors: Jane E. Hill

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Quality of life is an important component for many. With that in mind, everyone will experience some type of loss within his or her lifetime. A person can experience loss due to break up, separation, divorce, estrangement, or death. An individual may experience loss of a job, loss of capacity, or loss caused by human or natural-caused disasters. An individual’s response to such a loss is unique to them, and not everyone will seek services to assist them with their grief due to loss. Counseling can promote positive outcomes for clients that are grieving by addressing the client’s personal loss and helping the client process their grief. However, a lack of understanding on the part of counselors of how people grieve may result in negative client outcomes such as poor health, psychological distress, or an increased risk of depression. Education and training in grief counseling can improve counselors’ problem recognition and skills in treatment planning. The purpose of this study was to examine whether the Council for Accreditation of Counseling and Related Educational Programs (CACREP) master’s degree counseling students view themselves as having been adequately trained in grief theories and skills. Many people deal with grief issues that prevent them from having joy or purpose in their lives and that leaves them unable to engage in positive opportunities or relationships. This study examined CACREP-accredited master’s counseling students’ self-reported competency, training, and education in providing grief counseling. The implications for positive social change arising from the research may be to incorporate and promote education and training in grief theories and skills in a majority of counseling programs and to provide motivation to incorporate professional standards for grief training and practice in the mental health counseling field. The theoretical foundation used was modern grief theory based on John Bowlby’s work on Attachment Theory. The overall research question was how competent do master’s-level counselors view themselves regarding the education or training they received in grief theories or counseling skills in their CACREP-accredited studies. The author used a non-experimental, one shot survey comparative quantitative research design. Cicchetti’s Grief Counseling Competency Scale (GCCS) was administered to CACREP master’s-level counseling students enrolled in their practicum or internship experience, which resulted in 153 participants. Using a MANCOVA, there was significance found for relationships between coursework taken and (a) perceived assessment skills (p = .029), (b) perceived treatment skills (p = .025), and (c) perceived conceptual skills and knowledge (p = .003). Results of this study provided insight for CACREP master’s-level counseling programs to explore and discuss curriculum coursework inclusion of education and training in grief theories and skills.

Keywords: counselor education and training, grief education and training, grief and loss, quality of life

Procedia PDF Downloads 171
899 Genetics of Pharmacokinetic Drug-Drug Interactions of Most Commonly Used Drug Combinations in the UK: Uncovering Unrecognised Associations

Authors: Mustafa Malki, Ewan R. Pearson

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Tools utilized by health care practitioners to flag potential adverse drug reactions secondary to drug-drug interactions ignore individual genetic variation, which has the potential to markedly alter the severity of these interactions. To our best knowledge, there have been limited published studies on the impact of genetic variation on drug-drug interactions. Therefore, our aim in this project is the discovery of previously unrecognized, clinically important drug-drug-gene interactions (DDGIs) within the list of most commonly used drug combinations in the UK. The UKBB database was utilized to identify the top most frequently prescribed drug combinations in the UK with at least one route of interaction (over than 200 combinations were identified). We have recognised 37 common and unique interacting genes considering all of our drug combinations. Out of around 600 potential genetic variants found in these 37 genes, 100 variants have met the selection criteria (common variant with minor allele frequency ≥ 5%, independence, and has passed HWE test). The association between these variants and the use of each of our top drug combinations has been tested with a case-control analysis under the log-additive model. As the data is cross-sectional, drug intolerance has been identified from the genotype distribution as presented by the lower percentage of patients carrying the risky allele and on the drug combination compared to those free of these risk factors and vice versa with drug tolerance. In GoDARTs database, the same list of common drug combinations identified by the UKBB was utilized here with the same list of candidate genetic variants but with the addition of 14 new SNPs so that we have a total of 114 variants which have met the selection criteria in GoDARTs. From the list of the top 200 drug combinations, we have selected 28 combinations where the two drugs in each combination are known to be used chronically. For each of our 28 combinations, three drug response phenotypes have been identified (drug stop/switch, dose decrease, or dose increase of any of the two drugs during their interaction). The association between each of the three phenotypes belonging to each of our 28 drug combinations has been tested against our 114 candidate genetic variants. The results show replication of four findings between both databases : (1) Omeprazole +Amitriptyline +rs2246709 (A > G) variant in CYP3A4 gene (p-values and ORs with the UKBB and GoDARTs respectively = 0.048,0.037,0.92,and 0.52 (dose increase phenotype)) (2) Simvastatin + Ranitidine + rs9332197 (T > C) variant in CYP2C9 gene (0.024,0.032,0.81, and 5.75 (drug stop/switch phenotype)) (3) Atorvastatin + Doxazosin + rs9282564 (T > C) variant in ABCB1 gene (0.0015,0.0095,1.58,and 3.14 (drug stop/switch phenotype)) (4) Simvastatin + Nifedipine + rs2257401 (C > G) variant in CYP3A7 gene (0.025,0.019,0.77,and 0.30 (drug stop/switch phenotype)). In addition, some other non-replicated, but interesting, significant findings were detected. Our work also provides a great source of information for researchers interested in DD, DG, or DDG interactions studies as it has highlighted the top common drug combinations in the UK with recognizing 114 significant genetic variants related to drugs' pharmacokinetic.

Keywords: adverse drug reactions, common drug combinations, drug-drug-gene interactions, pharmacogenomics

Procedia PDF Downloads 145
898 Optimisation of Energy Harvesting for a Composite Aircraft Wing Structure Bonded with Discrete Macro Fibre Composite Sensors

Authors: Ali H. Daraji, Ye Jianqiao

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The micro electrical devices of the wireless sensor network are continuously developed and become very small and compact with low electric power requirements using limited period life conventional batteries. The low power requirement for these devices, cost of conventional batteries and its replacement have encouraged researcher to find alternative power supply represented by energy harvesting system to provide an electric power supply with infinite period life. In the last few years, the investigation of energy harvesting for structure health monitoring has increased to powering wireless sensor network by converting waste mechanical vibration into electricity using piezoelectric sensors. Optimisation of energy harvesting is an important research topic to ensure a flowing of efficient electric power from structural vibration. The harvesting power is mainly based on the properties of piezoelectric material, dimensions of piezoelectric sensor, its position on a structure and value of an external electric load connected between sensor electrodes. Larger surface area of sensor is not granted larger power harvesting when the sensor area is covered positive and negative mechanical strain at the same time. Thus lead to reduction or cancellation of piezoelectric output power. Optimisation of energy harvesting is achieved by locating these sensors precisely and efficiently on the structure. Limited published work has investigated the energy harvesting for aircraft wing. However, most of the published studies have simplified the aircraft wing structure by a cantilever flat plate or beam. In these studies, the optimisation of energy harvesting was investigated by determination optimal value of an external electric load connected between sensor electrode terminals or by an external electric circuit or by randomly splitting piezoelectric sensor to two segments. However, the aircraft wing structures are complex than beam or flat plate and mostly constructed from flat and curved skins stiffened by stringers and ribs with more complex mechanical strain induced on the wing surfaces. This aircraft wing structure bonded with discrete macro fibre composite sensors was modelled using multiphysics finite element to optimise the energy harvesting by determination of the optimal number of sensors, location and the output resistance load. The optimal number and location of macro fibre sensors were determined based on the maximization of the open and close loop sensor output voltage using frequency response analysis. It was found different optimal distribution, locations and number of sensors bounded on the top and the bottom surfaces of the aircraft wing.

Keywords: energy harvesting, optimisation, sensor, wing

Procedia PDF Downloads 289
897 Polymer Nanocomposite Containing Silver Nanoparticles for Wound Healing

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

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

Keywords: nanocomposite, wound healing, hydrogel, silver nanoparticle

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896 Synthesis of Functionalized-2-Aryl-2, 3-Dihydroquinoline-4(1H)-Ones via Fries Rearrangement of Azetidin-2-Ones

Authors: Parvesh Singh, Vipan Kumar, Vishu Mehra

Abstract:

Quinoline-4-ones represent an important class of heterocyclic scaffolds that have attracted significant interest due to their various biological and pharmacological activities. This heterocyclic unit also constitutes an integral component in drugs used for the treatment of neurodegenerative diseases, sleep disorders and in antibiotics viz. norfloxacin and ciprofloxacin. The synthetic accessibility and possibility of fictionalization at varied positions in quinoline-4-ones exemplifies an elegant platform for the designing of combinatorial libraries of functionally enriched scaffolds with a range of pharmacological profles. They are also considered to be attractive precursors for the synthesis of medicinally imperative molecules such as non-steroidal androgen receptor antagonists, antimalarial drug Chloroquine and martinellines with antibacterial activity. 2-Aryl-2,3-dihydroquinolin-4(1H)-ones are present in many natural and non-natural compounds and are considered to be the aza-analogs of favanones. The β-lactam class of antibiotics is generally recognized to be a cornerstone of human health care due to the unparalleled clinical efficacy and safety of this type of antibacterial compound. In addition to their biological relevance as potential antibiotics, β-lactams have also acquired a prominent place in organic chemistry as synthons and provide highly efficient routes to a variety of non-protein amino acids, such as oligopeptides, peptidomimetics, nitrogen-heterocycles, as well as biologically active natural and unnatural products of medicinal interest such as indolizidine alkaloids, paclitaxel, docetaxel, taxoids, cyptophycins, lankacidins, etc. A straight forward route toward the synthesis of quinoline-4-ones via the triflic acid assisted Fries rearrangement of N-aryl-βlactams has been reported by Tepe and co-workers. The ring expansion observed in this case was solely attributed to the inherent ring strain in β-lactam ring because -lactam failed to undergo rearrangement under reaction conditions. Theabovementioned protocol has been recently extended by our group for the synthesis of benzo[b]-azocinon-6-ones via a tandem Michael addition–Fries rearrangement of sorbyl anilides as well as for the single-pot synthesis of 2-aryl-quinolin-4(3H)-ones through the Fries rearrangement of 3-dienyl-βlactams. In continuation with our synthetic endeavours with the β-lactam ring and in view of the lack of convenient approaches for the synthesis of C-3 functionalized quinolin-4(1H)-ones, the present work describes the single-pot synthesis of C-3 functionalized quinolin-4(1H)-ones via the trific acid promoted Fries rearrangement of C-3 vinyl/isopropenyl substituted β-lactams. In addition, DFT calculations and MD simulations were performed to investigate the stability profles of synthetic compounds.

Keywords: dihydroquinoline, fries rearrangement, azetidin-2-ones, quinoline-4-ones

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895 Political Skills in Social Management and Responsibility of Media Studies

Authors: Musa Miah

Abstract:

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

Keywords: Bangladesh, Dhaka, social activities, political sociology

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894 Comparison of Microstructure, Mechanical Properties and Residual Stresses in Laser and Electron Beam Welded Ti–5Al–2.5Sn Titanium Alloy

Authors: M. N. Baig, F. N. Khan, M. Junaid

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Titanium alloys are widely employed in aerospace, medical, chemical, and marine applications. These alloys offer many advantages such as low specific weight, high strength to weight ratio, excellent corrosion resistance, high melting point and good fatigue behavior. These attractive properties make titanium alloys very unique and therefore they require special attention in all areas of processing, especially welding. In this work, 1.6 mm thick sheets of Ti-5Al-2,5Sn, an alpha titanium (α-Ti) alloy, were welded using electron beam (EBW) and laser beam (LBW) welding processes to achieve a full penetration Bead-on Plate (BoP) configuration. The weldments were studied using polarized optical microscope, SEM, EDS and XRD. Microhardness distribution across the weld zone and smooth and notch tensile strengths of the weldments were also recorded. Residual stresses using Hole-drill Strain Measurement (HDSM) method and deformation patterns of the weldments were measured for the purpose of comparison of the two welding processes. Fusion zone widths of both EBW and LBW weldments were found to be approximately equivalent owing to fairly similar high power densities of both the processes. Relatively less oxide content and consequently high joint quality were achieved in EBW weldment as compared to LBW due to vacuum environment and absence of any shielding gas. However, an increase in heat-affected zone width and partial ά-martensitic transformation infusion zone of EBW weldment were observed because of lesser cooling rates associated with EBW as compared with LBW. The microstructure infusion zone of EBW weldment comprised both acicular α and ά martensite within the prior β grains whereas complete ά martensitic transformation was observed within the fusion zone of LBW weldment. Hardness of the fusion zone in EBW weldment was found to be lower than the fusion zone of LBW weldment due to the observed microstructural differences. Notch tensile specimen of LBW exhibited higher load capacity, ductility, and absorbed energy as compared with EBW specimen due to the presence of high strength ά martensitic phase. It was observed that the sheet deformation and deformation angle in EBW weldment were more than LBW weldment due to relatively more heat retention in EBW which led to more thermal strains and hence higher deformations and deformation angle. The lowest residual stresses were found in LBW weldments which were tensile in nature. This was owing to high power density and higher cooling rates associated with LBW process. EBW weldment exhibited highest compressive residual stresses due to which the service life of EBW weldment is expected to improve.

Keywords: Laser and electron beam welding, Microstructure and mechanical properties, Residual stress and distortions, Titanium alloys

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893 Improving Patient and Clinician Experience of Oral Surgery Telephone Clinics

Authors: Katie Dolaghan, Christina Tran, Kim Hamilton, Amanda Beresford, Vicky Adams, Jamie Toole, John Marley

Abstract:

During the Covid 19 pandemic routine outpatient appointments were not possible face to face. That resulted in many branches of healthcare starting virtual clinics. These clinics have continued following the return to face to face patient appointments. With these new types of clinic it is important to ensure that a high standard of patient care is maintained. In order to improve patient and clinician experience of the telephone clinics a quality improvement project was carried out to ensure the patient and clinician experience of these clinics was enhanced whilst remaining a safe, effective and an efficient use of resources. The project began by developing a process map for the consultation process and agreed on the design of a driver diagram and tests of change. In plan do study act (PDSA) cycle1 a single consultant completed an online survey after every patient encounter over a 5 week period. Baseline patient responses were collected using a follow-up telephone survey for each patient. Piloting led to several iterations of both survey designs. Salient results of PDSA1 included; patients not receiving appointment letters, patients feeling more anxious about a virtual appointment and many would prefer a face to face appointment. The initial clinician data showed a positive response with a provisional diagnosis being reached in 96.4% of encounters. PDSA cycle 2 included provision of a patient information sheet and information leaflets relevant to the patients’ conditions were developed and sent following new patient telephone clinics with follow-up survey analysis as before to monitor for signals of change. We also introduced the ability for patients to send an images of their lesion prior to the consultation. Following the changes implemented we noted an improvement in patient satisfaction and, in fact, many patients preferring virtual clinics as it lead to less disruption of their working lives. The extra reading material both before and after the appointments eased patients’ anxiety around virtual clinics and helped them to prepare for their appointment. Following the patient feedback virtual clinics are now used for review patients as well, with all four consultants within the department continuing to utilise virtual clinics. During this presentation the progression of these clinics and the reasons that these clinics are still operating following the return to face to face appointments will be explored. The lessons that have been gained using a QI approach have helped to deliver an optimal service that is valid and reliable as well as being safe, effective and efficient for the patient along with helping reduce the pressures from ever increasing waiting lists. In summary our work in improving the quality of virtual clinics has resulted in improved patient satisfaction along with reduced pressures on the facilities of the health trust.

Keywords: clinic, satisfaction, telephone, virtual

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892 Tuberculosis Outpatient Treatment in the Context of Reformation of the Health Care System

Authors: Danylo Brindak, Viktor Liashko, Olexander Chepurniy

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Despite considerable experience in implementation of the best international approaches and services within response to epidemy of multi-drug resistant tuberculosis, the results of situation analysis indicate the presence of faults in this area. In 2014, Ukraine (for the first time) was included in the world’s five countries with the highest level of drug-resistant tuberculosis. The effectiveness of its treatment constitutes only 35% in the country. In this context, the increase in allocation of funds to control the epidemic of multidrug-resistant tuberculosis does not produce perceptible positive results. During 2001-2016, only the Global Fund to fight AIDS, Tuberculosis, and Malaria allocated to Ukraine more than USD 521,3 million for programs of tuberculosis and HIV/AIDS control. However, current conditions in post-Semashko system create little motivation for rational use of resources or cost control at inpatient TB facilities. There is no motivation to reduce overdue hospitalization and to target resources to priority sectors of modern tuberculosis control, including a model of care focused on the patient. In the presence of a line-item budget at medical institutions, based on the input factors as the ratios of beds and staff, there is a passive disposal of budgetary funds by health care institutions and their employees who have no motivation to improve quality and efficiency of service provision. Outpatient treatment of tuberculosis is being implemented in Ukraine since 2011 and has many risks, namely creation of parallel systems, low consistency through dependence on funding for the project, reduced the role of the family doctor, the fragmentation of financing, etc. In terms of reforming approaches to health system financing, which began in Ukraine in late 2016, NGO Infection Control in Ukraine conducted piloting of a new, motivating method of remuneration of employees in primary health care. The innovative aspect of this funding mechanism is cost according to results of treatment. The existing method of payment on the basis of the standard per inhabitant (per capita ratio) was added with motivating costs according to results of work. The effectiveness of such treatment of TB patients at the outpatient stage is 90%, while in whole on the basis of a current system the effectiveness of treatment of newly diagnosed pulmonary TB with positive swab is around 60% in the country. Even though Ukraine has 5.24 TB beds per 10 000 citizens. Implemented pilot model of ambulatory treatment will be used for the creation of costs system according to results of activities, the integration of TB and primary health and social services and their focus on achieving results, the reduction of inpatient treatment of tuberculosis.

Keywords: health care reform, multi-drug resistant tuberculosis, outpatient treatment efficiency, tuberculosis

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891 Ecosystem Approach in Aquaculture: From Experimental Recirculating Multi-Trophic Aquaculture to Operational System in Marsh Ponds

Authors: R. Simide, T. Miard

Abstract:

Integrated multi-trophic aquaculture (IMTA) is used to reduce waste from aquaculture and increase productivity by co-cultured species. In this study, we designed a recirculating multi-trophic aquaculture system which requires low energy consumption, low water renewal and easy-care. European seabass (Dicentrarchus labrax) were raised with co-cultured sea urchin (Paracentrotus lividus), deteritivorous polychaete fed on settled particulate matter, mussels (Mytilus galloprovincialis) used to extract suspended matters, macroalgae (Ulva sp.) used to uptake dissolved nutrients and gastropod (Phorcus turbinatus) used to clean the series of 4 tanks from fouling. Experiment was performed in triplicate during one month in autumn under an experimental greenhouse at the Institute Océanographique Paul Ricard (IOPR). Thanks to the absence of a physical filter, any pomp was needed to pressure water and the water flow was carried out by a single air-lift followed by gravity flow.Total suspended solids (TSS), biochemical oxygen demand (BOD5), turbidity, phytoplankton estimation and dissolved nutrients (ammonium NH₄, nitrite NO₂⁻, nitrate NO₃⁻ and phosphorus PO₄³⁻) were measured weekly while dissolved oxygen and pH were continuously recorded. Dissolved nutrients stay under the detectable threshold during the experiment. BOD5 decreased between fish and macroalgae tanks. TSS highly increased after 2 weeks and then decreased at the end of the experiment. Those results show that bioremediation can be well used for aquaculture system to keep optimum growing conditions. Fish were the only feeding species by an external product (commercial fish pellet) in the system. The others species (extractive species) were fed from waste streams from the tank above or from Ulva produced by the system for the sea urchin. In this way, between the fish aquaculture only and the addition of the extractive species, the biomass productivity increase by 5.7. In other words, the food conversion ratio dropped from 1.08 with fish only to 0.189 including all species. This experimental recirculating multi-trophic aquaculture system was efficient enough to reduce waste and increase productivity. In a second time, this technology has been reproduced at a commercial scale. The IOPR in collaboration with Les 4 Marais company run for 6 month a recirculating IMTA in 8000 m² of water allocate between 4 marsh ponds. A similar air-lift and gravity recirculating system was design and only one feeding species of shrimp (Palaemon sp.) was growth for 3 extractive species. Thanks to this joint work at the laboratory and commercial scales we will be able to challenge IMTA system and discuss about this sustainable aquaculture technology.

Keywords: bioremediation, integrated multi-trophic aquaculture (IMTA), laboratory and commercial scales, recirculating aquaculture, sustainable

Procedia PDF Downloads 143