Search results for: separated and reattached flow
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5346

Search results for: separated and reattached flow

2856 Cumulus-Oocyte Complexes and Follicular Fluid Proteins of Pig during Folliculogenesis

Authors: Panomporn Wisuthseriwong, Hatairuk Tungkasen, Siyaporn Namsongsan, Chanikarn Srinark, Mayuva Youngsabanant-Areekijseree

Abstract:

The objective of the present study was to evaluate the morphology of porcine cumulus-oocyte complexes (pCOCs) and follicular fluid during follicular development. The samples were obtained from local slaughterhouses in Nakorn Pathom Province, Thailand. Pigs were classified as either in the follicular phase or luteal phase. Porcine follicles (n = 3,510) were categorized as small (1-3 mm in diameters; n=2,910), medium (4-6 mm in diameters; n=530) and large (7-8 mm in diameters; n=70). Then pCOCs and follicular fluid were collected. Finally, we found that the oocytes can be categorized into intact cumulus cells layer oocyte, multi-cumulus cells layer oocyte, partial cumulus cells layer oocyte, completely denuded oocyte and degenerated oocyte. They showed high percentage of intact and multi-cumulus cells layer oocytes from small follicles (54.68%) medium follicles (69.06%) and large follicles (68.57%), which have high potential to develop into matured oocytes in vitro. Protein composition of the follicular fluid was separated by SDS-PAGE technique. The result shows that the protein molecular weight in the small and medium follicles are 23, 50, 66, 75, 92, 100, 132, 163, 225 and >225 kDa. Meanwhile, protein molecular weight in large follicles are 12, 16, 23, 50, 66, 75, 92, 100, 132, 163, 225 and >225 kDa. All proteins play an important role in promotion and regulation on development, maturation of oocytes and regulation of ovulation. We conclude that the results of discovery can be used porcine secretion proteins for supplement in IVM/IVF technology. Acknowledgements: The project was funded by a grant from Silpakorn University Research and Development Institute (SURDI) and Faculty of Science, Silpakorn University, Thailand.

Keywords: porcine follicles, porcine oocyte, follicular fluid, SDS-PAGE

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2855 T Cell Immunity Profile in Pediatric Obesity and Asthma

Authors: Mustafa M. Donma, Erkut Karasu, Burcu Ozdilek, Burhan Turgut, Birol Topcu, Burcin Nalbantoglu, Orkide Donma

Abstract:

The mechanisms underlying the association between obesity and asthma may be related to a decreased immunological tolerance induced by a defective function of regulatory T cells (Tregs). The aim of this study is to establish the potential link between these diseases and CD4+, CD25+ FoxP3+ Tregs as well as T helper cells (Ths) in children. This is a prospective case control study. Obese (n:40), asthmatic (n:40), asthmatic obese (n:40), and healthy children (n:40), who don't have any acute or chronic diseases, were included in this study. Obese children were evaluated according to WHO criteria. Asthmatic patients were chosen based on GINA criteria. Parents were asked to fill up the questionnaire. Informed consent forms were taken. Blood samples were marked with CD4+, CD25+ and FoxP3+ in order to determine Tregs and Ths by flow cytometric method. Statistical analyses were performed. p≤0.05 was chosen as meaningful threshold. Tregs exhibiting anti-inflammatory nature were significantly lower in obese (0,16%; p≤0,001), asthmatic (0,25%; p≤0,01) and asthmatic obese (0,29%; p≤0,05) groups than the control group (0,38%). Ths were counted higher in asthma group than the control (p≤0,01) and obese (p≤0,001)) groups. T cell immunity plays important roles in obesity and asthma pathogeneses. Decreased numbers of Tregs found in obese, asthmatic and asthmatic obese children may help to elucidate some questions in pathophysiology of these diseases. For HOMA-IR levels, any significant difference was not noted between control and obese groups, but statistically higher values were found for obese asthmatics. The values obtained in all groups were found to be below the critical cut off points. This finding has made the statistically significant difference observed between Tregs of obese, asthmatic, obese asthmatic, and control groups much more valuable. These findings will be useful in diagnosis and treatment of these disorders and future studies are needed. The production and propagation of Tregs may be promising in alternative asthma and obesity treatments.

Keywords: asthma, flow cytometry, pediatric obesity, T cells

Procedia PDF Downloads 346
2854 Determining Optimum Locations for Runoff Water Harvesting in W. Watir, South Sinai, Using RS, GIS, and WMS Techniques

Authors: H. H. Elewa, E. M. Ramadan, A. M. Nosair

Abstract:

Rainfall water harvesting is considered as an important tool for overcoming water scarcity in arid and semi-arid region. Wadi Watir in the southeastern part of Sinai Peninsula is considered as one of the main and active basins in the Gulf of Aqaba drainage system. It is characterized by steep hills mainly consist of impermeable rocks, whereas the streambeds are covered by a highly permeable mixture of gravel and sand. A comprehensive approach involving the integration of geographic information systems, remote sensing and watershed modeling was followed to identify the RWH capability in this area. Eight thematic layers, viz volume of annual flood, overland flow distance, maximum flow distance, rock or soil infiltration, drainage frequency density, basin area, basin slope and basin length were used as a multi-parametric decision support system for conducting weighted spatial probability models (WSPMs) to determine the potential areas for the RWH. The WSPMs maps classified the area into five RWH potentiality classes ranging from the very low to very high. Three performed WSPMs' scenarios for W. Watir reflected identical results among their maps for the high and very high RWH potentiality classes, which are the most suitable ones for conducting surface water harvesting techniques. There is also a reasonable match with respect to the potentiality of runoff harvesting areas with a probability of moderate, low and very low among the three scenarios. WSPM results have shown that the high and very high classes, which are the most suitable for the RWH are representing approximately 40.23% of the total area of the basin. Accordingly, several locations were decided for the establishment of water harvesting dams and cisterns to improve the water conditions and living environment in the study area.

Keywords: Sinai, Wadi Watir, remote sensing, geographic information systems, watershed modeling, runoff water harvesting

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2853 Influence of Sports Participation on Academic Performance among Afe Babalola University Student-Athletes

Authors: B. O. Diyaolu

Abstract:

The web created by sport in academics has made it difficult for it to be separated from adolescent educational development. The enthusiasm expressed towards sport by students in higher institutions is quite enormous. Primarily, academic performance should be the pride of all students but whether sports affect the academic performance of student-athletes remain an unknown fact. This study investigated the influence of sports participation on academic performance among Afe Babalola University student-athletes. Ex post facto research design was used. Two groups of students were used for the study; Student-athlete (SA) and Regular Students (RS). Purposive sampling technique was used to select 224 student-athletes, only those that are regular in the university sports team training were considered and their records (i.e. name, department, level, matriculation number, and phone number) were collected through the assistance of their coaches. For the regular students, purposive sampling technique was used to select 224 participants, only those that have no interest in sports were considered and their records were retrieved from the college registration officer. The first and second semester examination results of the two groups were compared in 10 general study courses without their knowledge, using descriptive statistics of frequency counts, mean, and standard deviation. Out of the 10 compared courses, 7 courses result showed no significant difference between students-athlete and regular students while student-athletes perform better in 3 practically oriented courses. Sports role in academics is quite significant. Exposure to sports can help build the confidence that athletes need especially when it comes to practical courses. Student-athletes can perform better in academics if the environment is friendly and not intimidating. Lecturers and coaches need to work together in order to build a well cultured and intelligent graduate.

Keywords: academic performance, regular students, sports participation, student-athlete, university sports team

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2852 Mobile Network Users Amidst Ultra-Dense Networks in 5G Using an Improved Coordinated Multipoint (CoMP) Technology

Authors: Johnson O. Adeogo, Ayodele S. Oluwole, O. Akinsanmi, Olawale J. Olaluyi

Abstract:

In this 5G network, very high traffic density in densely populated areas, most especially in densely populated areas, is one of the key requirements. Radiation reduction becomes one of the major concerns to secure the future life of mobile network users in ultra-dense network areas using an improved coordinated multipoint technology. Coordinated Multi-Point (CoMP) is based on transmission and/or reception at multiple separated points with improved coordination among them to actively manage the interference for the users. Small cells have two major objectives: one, they provide good coverage and/or performance. Network users can maintain a good quality signal network by directly connecting to the cell. Two is using CoMP, which involves the use of multiple base stations (MBS) to cooperate by transmitting and/or receiving at the same time in order to reduce the possibility of electromagnetic radiation increase. Therefore, the influence of the screen guard with rubber condom on the mobile transceivers as one major piece of equipment radiating electromagnetic radiation was investigated by mobile network users amidst ultra-dense networks in 5g. The results were compared with the same mobile transceivers without screen guards and rubber condoms under the same network conditions. The 5 cm distance from the mobile transceivers was measured with the help of a ruler, and the intensity of Radio Frequency (RF) radiation was measured using an RF meter. The results show that the intensity of radiation from various mobile transceivers without screen guides and condoms was higher than the mobile transceivers with screen guides and condoms when call conversation was on at both ends.

Keywords: ultra-dense networks, mobile network users, 5g, coordinated multi-point.

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2851 Investigation of External Pressure Coefficients on Large Antenna Parabolic Reflector Using Computational Fluid Dynamics

Authors: Varun K, Pramod B. Balareddy

Abstract:

Estimation of wind forces plays a significant role in the in the design of large antenna parabolic reflectors. Reflector surface accuracies are very sensitive to the gain of the antenna system at higher frequencies. Hence accurate estimation of wind forces becomes important, which is primary input for design and analysis of the reflector system. In the present work, numerical simulation of wind flow using Computational Fluid Dynamics (CFD) software is used to investigate the external pressure coefficients. An extensive comparative study has been made between the CFD results and the published wind tunnel data for different wind angle of attacks (α) acting over concave to convex surfaces respectively. Flow simulations using CFD are carried out to estimate the coefficients of Drag, Lift and Moment for the parabolic reflector. Coefficients of pressures (Cp) over the front and the rear face of the reflector are extracted over surface of the reflector to study the net pressure variations. These resultant pressure variations are compared with the published wind tunnel data for different angle of attacks. It was observed from the CFD simulations, both convex and concave face of reflector system experience a band of pressure variations for the positive and negative angle of attacks respectively. In the published wind tunnel data, Pressure variations over convex surfaces are assumed to be uniform and vice versa. Chordwise and spanwise pressure variations were calculated and compared with the published experimental data. In the present work, it was observed that the maximum pressure coefficients for α ranging from +30° to -90° and α=+90° was lower. For α ranging from +45° to +75°, maximum pressure coefficients were higher as compared to wind tunnel data. This variation is due to non-uniform pressure distribution observed over front and back faces of reflector. Variations in Cd, Cl and Cm over α=+90° to α=-90° was in close resemblance with the experimental data.

Keywords: angle of attack, drag coefficient, lift coefficient, pressure coefficient

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2850 Impact of Social Distancing on the Correlation Between Adults’ Participation in Learning and Acceptance of Technology

Authors: Liu Yi Hui

Abstract:

The COVID-19 pandemic in 2020 has globally affected all aspects of life, with social distancing and quarantine orders causing turmoil and learning in community colleges being temporarily paused. In fact, this is the first time that adult education has faced such a severe challenge. It forces researchers to reflect on the impact of pandemics on adult education and ways to respond. Distance learning appears to be one of the pedagogical tools capable of dealing with interpersonal isolation and social distancing caused by the pandemic. This research aims to examine whether the impact of social distancing during COVID-19 will lead to increased acceptance of technology and, subsequently, an increase in adults ’ willingness to participate in distance learning. The hypothesis that social distancing and the desire to participate in distance learning affects learners’ tendency to accept technology is investigated. Teachers ’ participation in distance education and acceptance of technology are used as adjustment variables with the relationship to “social distancing,” “participation in distance learning,” and “acceptance of technology” of learners. A questionnaire survey was conducted over a period of twelve months for teachers and learners at all community colleges in Taiwan who enrolled in a basic unit course. Community colleges were separated using multi-stage cluster sampling, with their locations being metropolitan, non-urban, south, and east as criteria. Using the G*power software, 660 samples were selected and analyzed. The results show that through appropriate pedagogical strategies or teachers ’ own acceptance of technology, adult learners’ willingness to participate in distance learning could be influenced. A diverse model of participation can be developed, improving adult education institutions’ ability to plan curricula to be flexible to avoid the risk associated with epidemic diseases.

Keywords: social distancing, adult learning, community colleges, technology acceptance model

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2849 Security Report Profiling for Mobile Banking Applications in Indonesia Based on OWASP Mobile Top 10-2016

Authors: Bambang Novianto, Rizal Aditya Herdianto, Raphael Bianco Huwae, Afifah, Alfonso Brolin Sihite, Rudi Lumanto

Abstract:

The mobile banking application is a type of mobile application that is growing rapidly. This is caused by the ease of service and time savings in making transactions. On the other hand, this certainly provides a challenge in security issues. The use of mobile banking can not be separated from cyberattacks that may occur which can result the theft of sensitive information or financial loss. The financial loss and the theft of sensitive information is the most avoided thing because besides harming the user, it can also cause a loss of customer trust in a bank. Cyberattacks that are often carried out against mobile applications are phishing, hacking, theft, misuse of data, etc. Cyberattack can occur when a vulnerability is successfully exploited. OWASP mobile Top 10 has recorded as many as 10 vulnerabilities that are most commonly found in mobile applications. In the others, android permissions also have the potential to cause vulnerabilities. Therefore, an overview of the profile of the mobile banking application becomes an urgency that needs to be known. So that it is expected to be a consideration of the parties involved for improving security. In this study, an experiment has been conducted to capture the profile of the mobile banking applications in Indonesia based on android permission and OWASP mobile top 10 2016. The results show that there are six basic vulnerabilities based on OWASP Mobile Top 10 that are most commonly found in mobile banking applications in Indonesia, i.e. M1:Improper Platform Usage, M2:Insecure Data Storage, M3:Insecure Communication, M5:Insufficient Cryptography, M7:Client Code Quality, and M9:Reverse Engineering. The most permitted android permissions are the internet, status network access, and telephone read status.

Keywords: mobile banking application, OWASP mobile top 10 2016, android permission, sensitive information, financial loss

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2848 Sulfonic Acid Functionalized Ionic Liquid in Combinatorial Approach: A Recyclable and Water Tolerant-Acidic Catalyst for Friedlander Quinoline Synthesis

Authors: Jafar Akbari

Abstract:

Quinolines are very important compounds partially because of their pharmacological properties which include wide applications in medicinal chemistry. notable among them are antimalarial drugs, anti-inflammatory agents, antiasthamatic, antibacterial, antihypertensive, and tyrosine kinase inhibiting agents. Despite quinoline usage in pharmaceutical and other industries, comparatively few methods for their preparation have been reported.The Friedlander annulation is one of the simplest and most straightforward methods for the synthesis of poly substituted quinolines. Although, modified methods employing lewis or br¢nsted acids have been reported for the synthesis of quinolines, the development of water stable acidic catalyst for quinoline synthesis is quite desirable. One of the most remarkable features of ionic liquids is that the yields can be optimized by changing the anions or the cations. Recently, sulfonic acid functionalized ionic liquids were used as solvent-catalyst for several organic reactions. We herein report the one pot domino approach for the synthesis of quinoline derivatives in Friedlander manner using TSIL as a catalyst. These ILs are miscible in water, and their homogeneous system is readily separated from the reaction product, combining advantages of both homogeneous and heterogeneous catalysis. In this reaction, the catalyst plays a dual role; it ensures an effective condensation and cyclization of 2-aminoaryl ketone with second carbonyl group and it also promotes the aromatization to the final product. Various types of quinolines from 2-aminoaryl ketones and β-ketoesters/ketones were prepared in 85-98% yields using the catalytic system of SO3-H functionalized ionic liquid/H2O. More importantly, the catalyst could be easily recycled for five times without loss of much activity.

Keywords: antimalarial drugs, green chemistry, ionic liquid, quinolines

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2847 Superparamagnetic Sensor with Lateral Flow Immunoassays as Platforms for Biomarker Quantification

Authors: M. Salvador, J. C. Martinez-Garcia, A. Moyano, M. C. Blanco-Lopez, M. Rivas

Abstract:

Biosensors play a crucial role in the detection of molecules nowadays due to their advantages of user-friendliness, high selectivity, the analysis in real time and in-situ applications. Among them, Lateral Flow Immunoassays (LFIAs) are presented among technologies for point-of-care bioassays with outstanding characteristics such as affordability, portability and low-cost. They have been widely used for the detection of a vast range of biomarkers, which do not only include proteins but also nucleic acids and even whole cells. Although the LFIA has traditionally been a positive/negative test, tremendous efforts are being done to add to the method the quantifying capability based on the combination of suitable labels and a proper sensor. One of the most successful approaches involves the use of magnetic sensors for detection of magnetic labels. Bringing together the required characteristics mentioned before, our research group has developed a biosensor to detect biomolecules. Superparamagnetic nanoparticles (SPNPs) together with LFIAs play the fundamental roles. SPMNPs are detected by their interaction with a high-frequency current flowing on a printed micro track. By means of the instant and proportional variation of the impedance of this track provoked by the presence of the SPNPs, quantitative and rapid measurement of the number of particles can be obtained. This way of detection requires no external magnetic field application, which reduces the device complexity. On the other hand, the major limitations of LFIAs are that they are only qualitative or semiquantitative when traditional gold or latex nanoparticles are used as color labels. Moreover, the necessity of always-constant ambient conditions to get reproducible results, the exclusive detection of the nanoparticles on the surface of the membrane, and the short durability of the signal are drawbacks that can be advantageously overcome with the design of magnetically labeled LFIAs. The approach followed was to coat the SPIONs with a specific monoclonal antibody which targets the protein under consideration by chemical bonds. Then, a sandwich-type immunoassay was prepared by printing onto the nitrocellulose membrane strip a second antibody against a different epitope of the protein (test line) and an IgG antibody (control line). When the sample flows along the strip, the SPION-labeled proteins are immobilized at the test line, which provides magnetic signal as described before. Preliminary results using this practical combination for the detection and quantification of the Prostatic-Specific Antigen (PSA) shows the validity and consistency of the technique in the clinical range, where a PSA level of 4.0 ng/mL is the established upper normal limit. Moreover, a LOD of 0.25 ng/mL was calculated with a confident level of 3 according to the IUPAC Gold Book definition. Its versatility has also been proved with the detection of other biomolecules such as troponin I (cardiac injury biomarker) or histamine.

Keywords: biosensor, lateral flow immunoassays, point-of-care devices, superparamagnetic nanoparticles

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2846 Micro-Filtration with an Inorganic Membrane

Authors: Benyamina, Ouldabess, Bensalah

Abstract:

The aim of this study is to use membrane technique for filtration of a coloring solution. the preparation of the micro-filtration membranes is based on a natural clay powder with a low cost, deposited on macro-porous ceramic supports. The micro-filtration membrane provided a very large permeation flow. Indeed, the filtration effectiveness of membrane was proved by the total discoloration of bromothymol blue solution with initial concentration of 10-3 mg/L after the first minutes.

Keywords: the inorganic membrane, micro-filtration, coloring solution, natural clay powder

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2845 Numerical Simulation of Production of Microspheres from Polymer Emulsion in Microfluidic Device toward Using in Drug Delivery Systems

Authors: Nizar Jawad Hadi, Sajad Abd Alabbas

Abstract:

Because of their ability to encapsulate and release drugs in a controlled manner, microspheres fabricated from polymer emulsions using microfluidic devices have shown promise for drug delivery applications. In this study, the effects of velocity, density, viscosity, and surface tension, as well as channel diameter, on microsphere generation were investigated using Fluent Ansys software. The software was programmed with the physical properties of the polymer emulsion such as density, viscosity and surface tension. Simulation will then be performed to predict fluid flow and microsphere production and improve the design of drug delivery applications based on changes in these parameters. The effects of capillary and Weber numbers are also studied. The results of the study showed that the size of the microspheres can be controlled by adjusting the speed and diameter of the channel. Narrower microspheres resulted from narrower channel widths and higher flow rates, which could improve drug delivery efficiency, while smaller microspheres resulted from lower interfacial surface tension. The viscosity and density of the polymer emulsion significantly affected the size of the microspheres, ith higher viscosities and densities producing smaller microspheres. The loading and drug release properties of the microspheres created with the microfluidic technique were also predicted. The results showed that the microspheres can efficiently encapsulate drugs and release them in a controlled manner over a period of time. This is due to the high surface area to volume ratio of the microspheres, which allows for efficient drug diffusion. The ability to tune the manufacturing process using factors such as speed, density, viscosity, channel diameter, and surface tension offers a potential opportunity to design drug delivery systems with greater efficiency and fewer side effects.

Keywords: polymer emulsion, microspheres, numerical simulation, microfluidic device

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2844 Determinants of Dividend Payout Ratio: Evidence form MENA Region

Authors: Abdul-Nasser El-Kassar, Walid Elgammal, Hisham Jawhar

Abstract:

This paper studies the determinants of the dividends payout ratio. The factors affecting the dividends payout ratio are to be identified. The study focuses only on the cement and construction industry within the MENA region in an attempt to isolate any incoherent behavior. The factors under consideration are: sales growth, ROE, ROA, ROS, debt to equity ratio, firm size, and free cash flow. Data were collected from official stock exchange markets in addition to annual reports. The study considered all firms that paid dividend in each of the three consecutive years starting from 2010 till 2012. Out of the 123 listed firms that work in cement and construction industry in MENA region, only 19 paid dividends in the three consecutive years 2010-12. Our sample consists of the 19 firms (57 observations) which are selected according to purposive sampling. Moreover, the study uses the homogeneous subcategory within the purposive sampling since only similar firms in the construction industry had been examined. The outcome of the study provides a vital insight into the determinants of dividends payout ratio of companies in MENA region. The results showed that the dividend payout ratio has a strong and positive relationship with return on assets and strong but negative relationship with return on equity. On the other hand, the results detected weak relationships between dividend payout ratio and sale growth, debt to equity ratio, firm size, and free cash flow. The study suggests that board of directors tend to compensate shareholders and minimize the agency cost by distributing a high portion of profits in form of dividends whenever return on equity decreases. Also, when the performance of the firm improves, and hence return on assets increases, boards of directors are more generous in distributing profits.

Keywords: dividends payout ratio, profitability firm size, free cashflow, debt to equity ratio

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2843 Calculation of the Supersonic Air Intake with the Optimization of the Shock Wave System

Authors: Elena Vinogradova, Aleksei Pleshakov, Aleksei Yakovlev

Abstract:

During the flight of a supersonic aircraft under various conditions (altitude, Mach, etc.), it becomes necessary to coordinate the operating modes of the air intake and engine. On the supersonic aircraft, it’s been done by changing various control factors (the angle of rotation of the wedge panels and etc.). This paper investigates the possibility of using modern optimization methods to determine the optimal position of the supersonic air intake wedge panels in order to maximize the total pressure recovery coefficient. Modern software allows us to conduct auto-optimization, which determines the optimal position of the control elements of the investigated product to achieve its maximum efficiency. In this work, the flow in the supersonic aircraft inlet has investigated and optimized the operation of the flaps of the supersonic inlet in an aircraft in a 2-D setting. This work has done using ANSYS CFX software. The supersonic aircraft inlet is a flat adjustable external compression inlet. The braking surface is made in the form of a three-stage wedge. The IOSO NM software package was chosen for optimization. Change in the position of the panels of the input device is carried out by changing the angle between the first and second steps of the three-stage wedge. The position of the rest of the panels is changed automatically. Within the framework of the presented work, the position of the moving air intake panel was optimized under fixed flight conditions of the aircraft under a certain engine operating mode. As a result of the numerical modeling, the distribution of total pressure losses was obtained for various cases of the engine operation, depending on the incoming flow velocity and the flight altitude of the aircraft. The results make it possible to obtain the maximum total pressure recovery coefficient under given conditions. Also, the initial geometry was set with a certain angle between the first and second wedge panels. Having performed all the calculations, as well as the subsequent optimization of the aircraft input device, it can be concluded that the initial angle was set sufficiently close to the optimal angle.

Keywords: optimal angle, optimization, supersonic air intake, total pressure recovery coefficient

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2842 Derivation of Human NK Cells from T Cell-Derived Induced Pluripotent Stem Cells Using Xenogeneic Serum-Free and Feeder Cell-Free Culture System

Authors: Aliya Sekenova, Vyacheslav Ogay

Abstract:

The derivation of human induced pluripotent stem cells (iPSCs) from somatic cells by direct reprogramming opens wide perspectives in the regenerative medicine. It means the possibility to develop the personal and, consequently, any immunologically compatible cells for applications in cell-based therapy. The purpose of our study was to develop the technology for the production of NK cells from T cell-derived induced pluripotent stem cells (TiPSCs) for subsequent application in adoptive cancer immunotherapy. Methods: In this study iPSCs were derived from peripheral blood T cells using Sendai virus vectors expressing Oct4, Sox2, Klf4 and c-Myc. Pluripotent characteristics of TiPSCs were examined and confirmed with alkaline phosphatase staining, immunocytochemistry and RT-PCR analysis. For NK cell differentiation, embryoid bodies (EB) formed from (TiPSCs) were cultured in xenogeneic serum-free medium containing human serum, IL-3, IL-7, IL-15, SCF, FLT3L without using M210-B4 and AFT-024 stromal feeder cells. After differentiation, NK cells were characterized with immunofluorescence analysis, flow cytometry and cytotoxicity assay. Results: Here, we for the first time demonstrate that TiPSCs can effectively differentiate into functionally active NK cells without M210-B4 and AFT-024 xenogeneic stroma cells. Immunofluorescence and flow cytometry analysis showed that EB-derived cells can differentiate into a homogeneous population of NK cell expressing high levels of CD56, CD45 and CD16 specific markers. Moreover, these cells significantly express killing activation receptors such as NKp44 and NKp46. In the comparative analysis, we observed that NK cells derived using feeder-free culture system have more high killing activity against K-562 tumor cells, than NK cells derived by feeder-dependent method. Thus, we think that our obtained data will be useful for the development of large-scale production of NK cells for translation into cancer immunotherapy.

Keywords: induced pluripotent stem cells, NK cells, T cells, cell diffentiation, feeder cell-free culture system

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2841 A Review of Pharmacological Prevention of Peri-and Post-Procedural Myocardial Injury After Percutaneous Coronary Intervention

Authors: Syed Dawood Md. Taimur, Md. Hasanur Rahman, Syeda Fahmida Afrin, Farzana Islam

Abstract:

The concept of myocardial injury, although first recognized from animal studies, is now recognized as a clinical phenomenon that may result in microvascular damage, no-reflow phenomenon, myocardial stunning, myocardial hibernation and ischemic preconditioning. The final consequence of this event is left ventricular (LV) systolic dysfunction leading to increased morbidity and mortality. The typical clinical case of reperfusion injury occurs in acute myocardial infarction (MI) with ST segment elevation in which an occlusion of a major epicardial coronary artery is followed by recanalization of the artery. This may occur either spontaneously or by means of thrombolysis and/or by primary percutaneous coronary intervention (PCI) with efficient platelet inhibition by aspirin (acetylsalicylic acid), clopidogrel and glycoprotein IIb/IIIa inhibitors. In recent years, percutaneous coronary intervention (PCI) has become a well-established technique for the treatment of coronary artery disease. PCI improves symptoms in patients with coronary artery disease and it has been increasing the safety of procedures. However, peri- and post-procedural myocardial injury, including angiographical slow coronary flow, microvascular embolization, and elevated levels of cardiac enzyme, such as creatine kinase and troponin-T and -I, has also been reported even in elective cases. Furthermore, myocardial reperfusion injury at the beginning of myocardial reperfusion, which causes tissue damage and cardiac dysfunction, may occur in cases of the acute coronary syndrome. Because patients with myocardial injury is related to larger myocardial infarction and have a worse long-term prognosis than those without myocardial injury, it is important to prevent myocardial injury during and/or after PCI in patients with coronary artery disease. To date, many studies have demonstrated that adjunctive pharmacological treatment suppresses myocardial injury and increases coronary blood flow during PCI procedures. In this review, we highlight the usefulness of pharmacological treatment in combination with PCI in attenuating myocardial injury in patients with coronary artery disease.

Keywords: coronary artery disease, percutaneous coronary intervention, myocardial injury, pharmacology

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2840 Biocontrol Effectiveness of Indigenous Trichoderma Species against Meloidogyne javanica and Fusarium oxysporum f. sp. radicis lycopersici on Tomato

Authors: Hajji Lobna, Chattaoui Mayssa, Regaieg Hajer, M'Hamdi-Boughalleb Naima, Rhouma Ali, Horrigue-Raouani Najet

Abstract:

In this study, three local isolates of Trichoderma (Tr1: T. viride, Tr2: T. harzianum and Tr3: T. asperellum) were isolated and evaluated for their biocontrol effectiveness under in vitro conditions and in greenhouse. In vitro bioassay revealed a biopotential control against Fusarium oxysporum f. sp. radicis lycopersici and Meloidogyne javanica (RKN) separately. All species of Trichoderma exhibited biocontrol performance and (Tr1) Trichoderma viride was the most efficient. In fact, growth rate inhibition of Fusarium oxysporum f. sp. radicis lycopersici (FORL) was reached 75.5% with Tr1. Parasitism rate of root-knot nematode was 60% for juveniles and 75% for eggs with the same one. Pots experiment results showed that Tr1 and Tr2, compared to chemical treatment, enhanced the plant growth and exhibited better antagonism against root-knot nematode and root-rot fungi separated or combined. All Trichoderma isolates revealed a bioprotection potential against Fusarium oxysporum f. sp. radicis lycopersici. When pathogen fungi inoculated alone, Fusarium wilt index and browning vascular rate were reduced significantly with Tr1 (0.91, 2.38%) and Tr2 (1.5, 5.5%), respectively. In the case of combined infection with Fusarium and nematode, the same isolate of Trichoderma Tr1 and Tr2 decreased Fusarium wilt index at 1.1 and 0.83 and reduced the browning vascular rate at 6.5% and 6%, respectively. Similarly, the isolate Tr1 and Tr2 caused maximum inhibition of nematode multiplication. Multiplication rate was declined at 4% with both isolates either tomato infected by nematode separately or concomitantly with Fusarium. The chemical treatment was moderate in activity against Meloidogyne javanica and Fusarium oxysporum f. sp. radicis lycopersici alone and combined.

Keywords: trichoderma spp., meloidogyne javanica, Fusarium oxysporum f.sp.radicis lycopersici, biocontrol

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2839 Energy Efficiency Approach to Reduce Costs of Ownership of Air Jet Weaving

Authors: Corrado Grassi, Achim Schröter, Yves Gloy, Thomas Gries

Abstract:

Air jet weaving is the most productive, but also the most energy consuming weaving method. Increasing energy costs and environmental impact are constantly a challenge for the manufacturers of weaving machines. Current technological developments concern with low energy costs, low environmental impact, high productivity, and constant product quality. The high degree of energy consumption of the method can be ascribed to the high need of compressed air. An energy efficiency method is applied to the air jet weaving technology. Such method identifies and classifies the main relevant energy consumers and processes from the exergy point of view and it leads to the identification of energy efficiency potentials during the weft insertion process. Starting from the design phase, energy efficiency is considered as the central requirement to be satisfied. The initial phase of the method consists of an analysis of the state of the art of the main weft insertion components in order to point out a prioritization of the high demanding energy components and processes. The identified major components are investigated to reduce the high demand of energy of the weft insertion process. During the interaction of the flow field coming from the relay nozzles within the profiled reed, only a minor part of the stream is really accelerating the weft yarn, hence resulting in large energy inefficiency. Different tools such as FEM analysis, CFD simulation models and experimental analysis are used in order to design a more energy efficient design of the involved components in the filling insertion. A different concept for the metal strip of the profiled reed is developed. The developed metal strip allows a reduction of the machine energy consumption. Based on a parametric and aerodynamic study, the designed reed transmits higher values of the flow power to the filling yarn. The innovative reed fulfills both the requirement of raising energy efficiency and the compliance with the weaving constraints.

Keywords: air jet weaving, aerodynamic simulation, energy efficiency, experimental validation, weft insertion

Procedia PDF Downloads 197
2838 Application of Hydrologic Engineering Centers and River Analysis System Model for Hydrodynamic Analysis of Arial Khan River

Authors: Najeeb Hassan, Mahmudur Rahman

Abstract:

Arial Khan River is one of the main south-eastward outlets of the River Padma. This river maintains a meander channel through its course and is erosional in nature. The specific objective of the research is to study and evaluate the hydrological characteristics in the form of assessing changes of cross-sections, discharge, water level and velocity profile in different stations and to create a hydrodynamic model of the Arial Khan River. Necessary data have been collected from Bangladesh Water Development Board (BWDB) and Center for Environment and Geographic Information Services (CEGIS). Satellite images have been observed from Google earth. In this study, hydrodynamic model of Arial Khan River has been developed using well known steady open channel flow code Hydrologic Engineering Centers and River Analysis System (HEC-RAS) using field surveyed geometric data. Cross-section properties at 22 locations of River Arial Khan for the years 2011, 2013 and 2015 were also analysed. 1-D HEC-RAS model has been developed using the cross sectional data of 2015 and appropriate boundary condition is being used to run the model. This Arial Khan River model is calibrated using the pick discharge of 2015. The applicable value of Mannings roughness coefficient (n) is adjusted through the process of calibration. The value of water level which ties with the observed data to an acceptable accuracy is taken as calibrated model. The 1-D HEC-RAS model then validated by using the pick discharges from 2009-2018. Variation in observed water level in the model and collected water level data is being compared to validate the model. It is observed that due to seasonal variation, discharge of the river changes rapidly and Mannings roughness coefficient (n) also changes due to the vegetation growth along the river banks. This river model may act as a tool to measure flood area in future. By considering the past pick flow discharge, it is strongly recommended to improve the carrying capacity of Arial Khan River to protect the surrounding areas from flash flood.

Keywords: BWDB, CEGIS, HEC-RAS

Procedia PDF Downloads 184
2837 Calibration and Validation of ArcSWAT Model for Estimation of Surface Runoff and Sediment Yield from Dhangaon Watershed

Authors: M. P. Tripathi, Priti Tiwari

Abstract:

Soil and Water Assessment Tool (SWAT) is a distributed parameter continuous time model and was tested on daily and fortnightly basis for a small agricultural watershed (Dhangaon) of Chhattisgarh state in India. The SWAT model recently interfaced with ArcGIS and called as ArcSWAT. The watershed and sub-watershed boundaries, drainage networks, slope and texture maps were generated in the environment of ArcGIS of ArcSWAT. Supervised classification method was used for land use/cover classification from satellite imageries of the years 2009 and 2012. Manning's roughness coefficient 'n' for overland flow and channel flow and Fraction of Field Capacity (FFC) were calibrated for monsoon season of the years 2009 and 2010. The model was validated on a daily basis for the years 2011 and 2012 by using the observed daily rainfall and temperature data. Calibration and validation results revealed that the model was predicting the daily surface runoff and sediment yield satisfactorily. Sensitivity analysis showed that the annual sediment yield was inversely proportional to the overland and channel 'n' values whereas; annual runoff and sediment yields were directly proportional to the FFC. The model was also tested (calibrated and validated) for the fortnightly runoff and sediment yield for the year 2009-10 and 2011-12, respectively. Simulated values of fortnightly runoff and sediment yield for the calibration and validation years compared well with their observed counterparts. The calibration and validation results revealed that the ArcSWAT model could be used for identification of critical sub-watershed and for developing management scenarios for the Dhangaon watershed. Further, the model should be tested for simulating the surface runoff and sediment yield using generated rainfall and temperature before applying it for developing the management scenario for the critical or priority sub-watersheds.

Keywords: watershed, hydrologic and water quality, ArcSWAT model, remote sensing, GIS, runoff and sediment yield

Procedia PDF Downloads 379
2836 Modeling and Calculation of Physical Parameters of the Pollution of Water by Oil and Materials in Suspensions

Authors: Ainas Belkacem, Fourar Ali

Abstract:

The present study focuses on the mathematical modeling and calculation of physical parameters of water pollution by oil and sand in regime fully dispersed in water. In this study, the sand particles and oil are suspended in the case of fully developed turbulence. The study consists to understand, model and predict the viscosity, the structure and dynamics of these types of mixtures. The work carried out is Numerical and validated by experience.

Keywords: multi phase flow, pollution, suspensions, turbulence

Procedia PDF Downloads 238
2835 Dental Education in Brazil: A Systematic Literature Review

Authors: Fabiane Alves Farias Guimarães, Rodrigo Otávio Moretti-Pires, Ana Lúcia Schaefer Ferreira de Mello

Abstract:

Introduction: Considering the last changes in Brazilian Health and Higher Educational Systems, the production of scientific knowledge regarding dental education and training has been increasing. The National Curriculum Guidelines for undergraduate courses in Dentistry established in 2002 the principles and procedures to perform a more generalist dental professional profile. Objectives: To perform a systematic review of the Brazilian scientific literature about dental education and training. Methods: The systematic review was conducted considering the Lilacs - Latin American Literature in Health Sciences and SciELO - Scientific Electronic Library Online data bases, using the combination of key words dentistry, education, teaching or training. It was select original research articles, published between 2010 and 2013, in Portuguese. Results: Based on the selection criteria, it was found 23 articles. In order to organize the outcomes, the analysis was separated in three themes: Ethical aspects of education (3 articles), integrating dental service with training (10 articles) and Dental education and the Brazilian curriculum guidelines (10 articles). Most of the studies were published between 2011 and 2012 (35% each) and were held in public universities. The studied populations included dental students, teachers, universities directors, health managers and dentists. The qualitative methodological approach was predominant. Conclusion: It was possible to identify a transience time in Brazilian undergraduate courses in Dentistry after curricular changes. The produced literature shows some advances, as the incorporation of ethical values on dental education and the inclusion of new practices environments for students by integrating education and training in diversified dental services scenarios.

Keywords: Teaching, Dental Students, Human resources in dentistry

Procedia PDF Downloads 532
2834 The Effect of Online Analyzer Malfunction on the Performance of Sulfur Recovery Unit and Providing a Temporary Solution to Reduce the Emission Rate

Authors: Hamid Reza Mahdipoor, Mehdi Bahrami, Mohammad Bodaghi, Seyed Ali Akbar Mansoori

Abstract:

Nowadays, with stricter limitations to reduce emissions, considerable penalties are imposed if pollution limits are exceeded. Therefore, refineries, along with focusing on improving the quality of their products, are also focused on producing products with the least environmental impact. The duty of the sulfur recovery unit (SRU) is to convert H₂S gas coming from the upstream units to elemental sulfur and minimize the burning of sulfur compounds to SO₂. The Claus process is a common process for converting H₂S to sulfur, including a reaction furnace followed by catalytic reactors and sulfur condensers. In addition to a Claus section, SRUs usually consist of a tail gas treatment (TGT) section to decrease the concentration of SO₂ in the flue gas below the emission limits. To operate an SRU properly, the flow rate of combustion air to the reaction furnace must be adjusted so that the Claus reaction is performed according to stoichiometry. Accurate control of the air demand leads to an optimum recovery of sulfur during the flow and composition fluctuations in the acid gas feed. Therefore, the major control system in the SRU is the air demand control loop, which includes a feed-forward control system based on predetermined feed flow rates and a feed-back control system based on the signal from the tail gas online analyzer. The use of online analyzers requires compliance with the installation and operation instructions. Unfortunately, most of these analyzers in Iran are out of service for different reasons, like the low importance of environmental issues and a lack of access to after-sales services due to sanctions. In this paper, an SRU in Iran was simulated and calibrated using industrial experimental data. Afterward, the effect of the malfunction of the online analyzer on the performance of SRU was investigated using the calibrated simulation. The results showed that an increase in the SO₂ concentration in the tail gas led to an increase in the temperature of the reduction reactor in the TGT section. This increase in temperature caused the failure of TGT and increased the concentration of SO₂ from 750 ppm to 35,000 ppm. In addition, the lack of a control system for the adjustment of the combustion air caused further increases in SO₂ emissions. In some processes, the major variable cannot be controlled directly due to difficulty in measurement or a long delay in the sampling system. In these cases, a secondary variable, which can be measured more easily, is considered to be controlled. With the correct selection of this variable, the main variable is also controlled along with the secondary variable. This strategy for controlling a process system is referred to as inferential control" and is considered in this paper. Therefore, a sensitivity analysis was performed to investigate the sensitivity of other measurable parameters to input disturbances. The results revealed that the output temperature of the first Claus reactor could be used for inferential control of the combustion air. Applying this method to the operation led to maximizing the sulfur recovery in the Claus section.

Keywords: sulfur recovery, online analyzer, inferential control, SO₂ emission

Procedia PDF Downloads 75
2833 Parametric Studies of Ethylene Dichloride Purification Process

Authors: Sh. Arzani, H. Kazemi Esfeh, Y. Galeh Zadeh, V. Akbari

Abstract:

Ethylene dichloride is a colorless liquid with a smell like chloroform. EDC is classified in the simple hydrocarbon group which is obtained from chlorinating ethylene gas. Its chemical formula is C2H2Cl2 which is used as the main mediator in VCM production. Therefore, the purification process of EDC is important in the petrochemical process. In this study, the purification unit of EDC was simulated, and then validation was performed. Finally, the impact of process parameter was studied for the degree of EDC purity. The results showed that by increasing the feed flow, the reflux impure combinations increase and result in an EDC purity decrease.

Keywords: ethylene dichloride, purification, edc, simulation

Procedia PDF Downloads 316
2832 Directors’ Liability for Losses Incurred in the Management of PT Merpati Nusantara Airlines, Persero

Authors: Eny Suastuti

Abstract:

This paper is about state’s capital equity in establishing State-owned Company (PT Merpati Persero). Under private law regime, PT Merpati Persero equity is a state asset allocated separately from the State Budget. Consequently, it is no longer a state asset; rather, it becomes a part of company assets. The adoption of Act No. 17 of 2003 on State Finance, Act No. 31 of 1999, which is amended by Act No. 20 of 2001 on Eradication of Corrupt Practices, Act No. 15 of 2004 on Auditing, Management, and Accountability of State Finance, and Act No. 15 of 2006 Audit Board raises legal issues of whether State-owned Company’s (PT Merpati Persero) loss may be deemed as loss on state finance made by the Directors of PT Merpati Persero, which implication leads to corrupt practices conducted by the Directors. The principle of civil law states that state assets are separated from the state budget is not a government asset. Therefore the case of a lease agreement 2 (two) units of Boeing 737-400 and Boeing 737-500 between PT Merpati Nusantara Airlines with companies Third Stone Aircraft Leasing Group (TALG) the United States cannot be prosecuted under Articles 2 and 3 of Act No. 31 of 1999 Jo Act No. 20 of 2001 on Eradication of Corrupt Practices (Law PTPK). From this paper, three things are found. First, state’s capital equity, which has been allocated separately from state assets in establishing the PT Merpati Perserois not state asset; rather, it is company’s asset. Second, in the case of mismanagement leading to company loss, the Directors of PT Merpati Persero may not be charged with committing corrupt practice as prescribed in Articles 2 and 3 of Corrupt Practices Eradication Law. Third, misperception has been made by judicial practices since the courts consider loss in certain transaction made by Directors of PT Merpati Persero to be loss of state finance whose implication is applicability of Articles 2 and 3 of Corrupt Practices Eradication Law.

Keywords: corrupt practice, loss, state's capital equity, state finance (PT Merpati Persero)

Procedia PDF Downloads 261
2831 Exploring the Bifunctional Organocatalysts for Asymmetric Synthesis of 3-Substituted-3-Aminooxindoles

Authors: Jasneet Kaur, Swapandeep Singh Chimni

Abstract:

The unfavorable use of metal-based catalysts that are often extortionate and toxic can be overcome by using small organic molecules known as organocatalysts. A variety of small organic molecules, including Brønsted/Lewis bases and acids, based on sulfonic acids, phosphoric acids, amines, phosphines or carbenes, Cinchona alkaloids, have been used as organocatalysts. One of the key reasons for using organocatalysis is their ability to be effectively removed from the final product in comparison to the metallic counterparts, which are exceedingly difficult to remove. The present investigation seeks to explore the catalytic nature of Cinchona alkaloids as an organocatalyst for enantioselective synthesis of 3-substituted-3-aminooxindole, which is known to exhibit a variety of biological activities and pharmacological activities. In this context, an organocatalytic asymmetric route for the synthesis of 3-aminooxindoles via reaction of isatin imine with α-acetoxy-β-ketoesters has been developed. The bifunctional Cinchona derived thiourea catalyzed the reaction of α-acetoxy-β-ketoesters derivatives with isatin imine to afford 3-substituted-aminooxindole derivatives in up to 93% yield, 95% enantiomeric excess and >20:1 diastereomeric ratio. The reaction was performed at room temperature for two hours using 10 mol% of catalyst, in the presence of 4Å molecular sieves in tetrahydrofuran as a solvent at ambient temperature. After the completion of the reaction, the pure product could be easily separated by using column chromatography using hexane and ethyl acetate as solvents. In conclusion, the catalytic potential of Cinchona derived chiral thiourea-tertiary amine catalyst was explored for an organocatalytic enantioselective Mannich reaction of β-ketoester derivatives with various isatin imine derivatives under mild conditions.

Keywords: asymmetric synthesis, aminooxindoles, enantioselective, isatin imine

Procedia PDF Downloads 114
2830 Identifying and Quantifying Factors Affecting Traffic Crash Severity under Heterogeneous Traffic Flow

Authors: Praveen Vayalamkuzhi, Veeraragavan Amirthalingam

Abstract:

Studies on safety on highways are becoming the need of the hour as over 400 lives are lost every day in India due to road crashes. In order to evaluate the factors that lead to different levels of crash severity, it is necessary to investigate the level of safety of highways and their relation to crashes. In the present study, an attempt is made to identify the factors that contribute to road crashes and to quantify their effect on the severity of road crashes. The study was carried out on a four-lane divided rural highway in India. The variables considered in the analysis includes components of horizontal alignment of highway, viz., straight or curve section; time of day, driveway density, presence of median; median opening; gradient; operating speed; and annual average daily traffic. These variables were considered after a preliminary analysis. The major complexities in the study are the heterogeneous traffic and the speed variation between different classes of vehicles along the highway. To quantify the impact of each of these factors, statistical analyses were carried out using Logit model and also negative binomial regression. The output from the statistical models proved that the variables viz., horizontal components of the highway alignment; driveway density; time of day; operating speed as well as annual average daily traffic show significant relation with the severity of crashes viz., fatal as well as injury crashes. Further, the annual average daily traffic has significant effect on the severity compared to other variables. The contribution of highway horizontal components on crash severity is also significant. Logit models can predict crashes better than the negative binomial regression models. The results of the study will help the transport planners to look into these aspects at the planning stage itself in the case of highways operated under heterogeneous traffic flow condition.

Keywords: geometric design, heterogeneous traffic, road crash, statistical analysis, level of safety

Procedia PDF Downloads 302
2829 A Proteomic Approach for Discovery of Microbial Cellulolytic Enzymes

Authors: M. S. Matlala, I. Ignatious

Abstract:

Environmental sustainability has taken the center stage in human life all over the world. Energy is the most essential component of our life. The conventional sources of energy are non-renewable and have a detrimental environmental impact. Therefore, there is a need to move from conventional to non-conventional renewable energy sources to satisfy the world’s energy demands. The study aimed at screening for microbial cellulolytic enzymes using a proteomic approach. The objectives were to screen for microbial cellulases with high specific activity and separate the cellulolytic enzymes using a combination of zymography and two-dimensional (2-D) gel electrophoresis followed by tryptic digestion, Matrix-assisted Laser Desorption Ionisation-Time of Flight (MALDI-TOF) and bioinformatics analysis. Fungal and bacterial isolates were cultured in M9 minimal and Mandel media for a period of 168 hours at 60°C and 30°C with cellobiose and Avicel as carbon sources. Microbial cells were separated from supernatants through centrifugation, and the crude enzyme from the cultures was used for the determination of cellulase activity, zymography, SDS-PAGE, and two-dimensional gel electrophoresis. Five isolates, with lytic action on carbon sources studied, were a bacterial strain (BARK) and fungal strains (VCFF1, VCFF14, VCFF17, and VCFF18). Peak cellulase production by the selected isolates was found to be 3.8U/ml, 2.09U/ml, 3.38U/ml, 3.18U/ml, and 1.95U/ml, respectively. Two-dimensional gel protein maps resulted in the separation and quantitative expression of different proteins by the microbial isolates. MALDI-TOF analysis and database search showed that the expressed proteins in this study closely relate to different glycoside hydrolases produced by other microbial species with an acceptable confidence level of 100%.

Keywords: cellulases, energy, two-dimensional gel electrophoresis, matrix-assisted laser desorption ionisation-time of flight, MALDI-TOF MS

Procedia PDF Downloads 134
2828 Sizing of Drying Processes to Optimize Conservation of the Nuclear Power Plants on Stationary

Authors: Assabo Mohamed, Bile Mohamed, Ali Farah, Isman Souleiman, Olga Alos Ramos, Marie Cadet

Abstract:

The life of a nuclear power plant is regularly punctuated by short or long period outages to carry out maintenance operations and/or nuclear fuel reloading. During these stops periods, it is essential to conserve all the secondary circuit equipment to avoid corrosion priming. This kind of circuit is one of the main components of a nuclear reactor. Indeed, the conservation materials on shutdown of a nuclear unit improve circuit performance and reduce the maintenance cost considerably. This study is a part of the optimization of the dry preservation of equipment from the water station of the nuclear reactor. The main objective is to provide tools to guide Electricity Production Nuclear Centre (EPNC) in order to achieve the criteria required by the chemical specifications of conservation materials. A theoretical model of drying exchangers of water station is developed by the software Engineering Equation Solver (EES). It used to size requirements and air quality needed for dry conservation of equipment. This model is based on heat transfer and mass transfer governing the drying operation. A parametric study is conducted to know the influence of aerothermal factor taking part in the drying operation. The results show that the success of dry conservation of equipment of the secondary circuit of nuclear reactor depends strongly on the draining, the quality of drying air and the flow of air injecting in the secondary circuit. Finally, theoretical case study performed on EES highlights the importance of mastering the entire system to balance the air system to provide each exchanger optimum flow depending on its characteristics. From these results, recommendations to nuclear power plants can be formulated to optimize drying practices and achieve good performance in the conservation of material from the water at the stop position.

Keywords: dry conservation, optimization, sizing, water station

Procedia PDF Downloads 262
2827 Sound Quality Analysis of Sloshing Noise from a Rectangular Tank

Authors: Siva Teja Golla, B. Venkatesham

Abstract:

The recent technologies in hybrid and high-end cars have subsided the noise from major sources like engines and transmission systems. This resulted in the unmasking of the previously subdued noises. These noises are becoming noticeable to the passengers, causing annoyance to them and affecting the perceived quality of the vehicle. Sloshing in the fuel tank is one such source of noise. Sloshing occurs due to the excitations undergone by the fuel tank due to the vehicle's movement. Sloshing noise occurs due to the interaction of the fluid with the surrounding tank walls or with the fluid itself. The noise resulting from the interaction of the fluid with the structure is ‘Hit noise’, and the noise due to fluid-fluid interaction is ‘Splash noise’. The type of interactions the fluid undergoes inside the tank, and the type of noise generated depends on a variety of factors like the fill level of the tank, type of fluid, presence of objects like baffles inside the tank, type and strength of the excitation, etc. There have been studies done to understand the effect of each of these parameters on the generation of different types of sloshing noises. But little work is done in the psychoacoustic aspect of these sounds. The psychoacoustic study of the sloshing noises gives an understanding of the level of annoyance it can cause to the passengers and helps in taking necessary measures to address it. In view of this, the current paper focuses on the calculation of the psychoacoustic parameters like loudness, sharpness, roughness and fluctuation strength for the sloshing noise. As the noise generation mechanisms for the hit and splash noises are different, these parameters are calculated separately for them. For this, the fluid flow regimes that predominantly cause the hit-and-splash noises are to be separately emulated inside the tank. This is done through a reciprocating test rig, which imposes reciprocating excitation to a rectangular tank filled with the fluid. By varying the frequency of excitation, the fluid flow regimes with the predominant generation of hit-and-splash noises can be separately created inside the tank. These tests are done in a quiet room and the noise generated is captured using microphones and is used for the calculation of psychoacoustic parameters of the sloshing noise. This study also includes the effect of fill level and the presence of baffles inside the tank on these parameters.

Keywords: sloshing, hit noise, splash noise, sound quality

Procedia PDF Downloads 30