Search results for: ring opening polymerization (ROP)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1143

Search results for: ring opening polymerization (ROP)

213 Evaluation of Chemoprotective Effect of NBRIQU16 against N-Methyl-N-Nitro-N-Nitrosoguanidine and NaCl-Induced Gastric Carcinomas in Wistar Rats

Authors: Lubna Azmi, Ila Shukla, Shyam Sundar Gupta, Padam Kant, C. V. Rao

Abstract:

To investigate the chemoprotective potential of NBRIQU16 chemotype isolated from Argyreia speciosa (Family: Convolvulaceae) on N-methyl-N-nitro-N-nitrosoguanidine (MNNG) and NaCl-induced gastric carcinomas in Wistar rats. Forty-six male 6-week-old Wistar rats were divided into two groups. Thirty rats in group A were fed with a diet supplemented with 8 % NaCl for 20 weeks and simultaneously given N-methyl-N’-nitro-N-nitrosoguanidine (MNNG) in drinking water at a concentration of 100 ug/ml for the first 17 weeks. After administration of the carcinogen, 200 and 400 mg/kg of NBRIQU16 were administered orally once a day throughout the study. From week 18, these rats were given normal water. From week 21, these rats were fed with a normal diet for 15 weeks. Group B containing 16 rats was fed standard diet for thirty-five days. It served as control. Ten rats from group A were sacrificed after 20 weeks. Scarification of remaining animals was conducted after 35 weeks. Entire stomach and some part of the duodenum were incised parallel to the greater curvature, and the samples were collected. After opening the stomach location and size of tumors were recorded. The number of tumors with their locations and sizes were recorded. Expression of survivin was examined by recording the Immunohistochemistry of the specimens. The treatment with NBRIQU16 significantly reduced the nodule incidence and nodule multiplicity in the rats after MNNG administration. Surviving expression in glandular stomachs of normal rats, of rats in middle induction period, in adenocarcinomas and NBRIQU16 treated tissues adjacent to tumor were 0, 42.0 %, 79.3%, and 36.4 %, respectively. Expression of survivin was significantly different as compared to the normal rats. Histological observations of stomach tissues too correlated with the biochemical observations.These finding powerfully supports that NBRIQU16 chemopreventive effect by suppressing the tumor burden and restoring the activities of gastric cancer marker enzymes on MNNG and NaCl-induced gastric carcinomas in Wistar rats.

Keywords: Argyreia speciosa, gastric carcinoma, immunochemistry, NBRIQU16

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212 A Study on Thermal and Flow Characteristics by Solar Radiation for Single-Span Greenhouse by Computational Fluid Dynamics Simulation

Authors: Jonghyuk Yoon, Hyoungwoon Song

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Recently, there are lots of increasing interest in a smart farming that represents application of modern Information and Communication Technologies (ICT) into agriculture since it provides a methodology to optimize production efficiencies by managing growing conditions of crops automatically. In order to obtain high performance and stability for smart greenhouse, it is important to identify the effect of various working parameters such as capacity of ventilation fan, vent opening area and etc. In the present study, a 3-dimensional CFD (Computational Fluid Dynamics) simulation for single-span greenhouse was conducted using the commercial program, Ansys CFX 18.0. The numerical simulation for single-span greenhouse was implemented to figure out the internal thermal and flow characteristics. In order to numerically model solar radiation that spread over a wide range of wavelengths, the multiband model that discretizes the spectrum into finite bands of wavelength based on Wien’s law is applied to the simulation. In addition, absorption coefficient of vinyl varied with the wavelength bands is also applied based on Beer-Lambert Law. To validate the numerical method applied herein, the numerical results of the temperature at specific monitoring points were compared with the experimental data. The average error rates (12.2~14.2%) between them was shown and numerical results of temperature distribution are in good agreement with the experimental data. The results of the present study can be useful information for the design of various greenhouses. This work was supported by Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (IPET) through Advanced Production Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA)(315093-03).

Keywords: single-span greenhouse, CFD (computational fluid dynamics), solar radiation, multiband model, absorption coefficient

Procedia PDF Downloads 133
211 Concentration Conditions of Industrially Valuable Accumulations of Gold Ore Mineralization of the Tulallar Ore-Bearing Structure

Authors: Narmina Ismayilova, Shamil Zabitov, Fuad Askerzadeh, Raqif Seyfullayev

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Tulallar volcano-tectonic structure is located in the conjugation zone of the Gekgel horst-uplift, Dashkesan, and Agzhakend synclinorium. Regionally, these geological structures are an integral part of the Lok-Karabakh island arc system. Tulallar field is represented by three areas (Central, East, West). The area of the ore field is located within a partially eroded oblong volcano-tectonic depression. In the central part, the core is divided by the deep Tulallar-Chiragdara-Toganalinsky fault with arcuate fragments of the ring structure into three blocks -East, Central, and West, within which the same areas of the Tulallar field are located. In general, for the deposit, the position of both ore-bearing vein zones and ore-bearing blocks is controlled by fractures of two systems - sub-latitudinal and near-meridional orientations. Mineralization of gold-sulfide ores is confined to these zones of disturbances. The zones have a northwestern and northeastern (near-meridian) strike with a steep dip (70-85◦) to the southwest and southeast. The average thickness of the zones is 35 m; they are traced for 2.5 km along the strike and 500 m along with the dip. In general, for the indicated thickness, the zones contain an average of 1.56 ppm Au; however, areas enriched in noble metal are distinguished within them. The zones are complicated by postore fault tectonics. Gold mineralization is localized in the Kimmeridgian volcanics of andesi-basalt-porphyritic composition and their vitrolithoclastic, agglomerate tuffs, and tuff breccias. For the central part of the Tulallar ore field, a map of geochemical anomalies was built on the basis of analysis data carried out in an international laboratory. The total gold content ranges from 0.1-5 g/t, and in some places, even more than 5 g/t. The highest gold content is observed in the monoquartz facies among the secondary quartzites with quartz veins. The smallest amount of gold content appeared in the quartz-kaolin facies. And also, anomalous values of gold content are located in the upper part of the quartz vein. As a result, an en-echelon arrangement of anomalous values of gold along the strike and dip was revealed.

Keywords: geochemical anomaly, gold deposit, mineralization, Tulallar

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210 The Effect of a Reactive Poly (2-Vinyl-2-Oxazoline) Monolayer of Carbon Fiber Surface on the Mechanical Property of Carbon Fiber/Polypropylene Composite Using Maleic Anhydride Grafted Polypropylene

Authors: Teruya Goto, Hokuto Chiba, Tatsuhiro Takahashi

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Carbon fiber reinforced thermoplastic resin using short carbon fiber has been produced by melt mixing and the improvement of mechanical properties has been frequently reported up to now. One of the most frequently reported enhancement has been seen in carbon fiber / polypropylene (PP) composites by adding small amount of maleic anhydride grafted polypropylene (MA-g-PP) into PP matrix. However, the further enhancement of tensile strength and tensile modules has been expected for lightning the composite more. Our present research aims to improve the mechanical property by using a highly reactive monolayer polymer, which can react with both COOH of carbon fiber surface and maleic anhydride of MA-g-PP in the matrix, on carbon fiber for PP/CF composite. It has been known that oxazoline has much higher reactivity with COOH without catalysts, compared with amine group and alcohol OH group. However, oxazoline group has not been used for the interface. To achieve the purpose, poly-2-vinyl-2-oxazoline (Pvozo), having highly reactivity with COOH and maleic anhydride, has been originally synthesized through radical polymerization using 2-vinyl-2-oxazoline as a monomer, resulting in the Mw around 140,000. Monolayer Pvozo chemically reacted on CF was prepared in 1-methoxy-2-propanol solution of Pvozo by heating at 100oC for 3 hours. After this solution treatment, unreacted Pvozo was completely washed out by methanol, resulting the uniform formation of the monolayer Pvozo on CF. Monolayer Pvozo coated CF was melt mixed by with PP and a small amount of MA-g-PP for the preparation of the composite samples using a batch type melt mixer. With performing the tensile strength tests of the composites, the tensile strength of CF/MA-g-PP/PP showed 40% increase, compared to that of CF/PP. While, that of Pvozo coated CF/MA-g-PP/PP exhibited 80% increase, compared to that of CF/PP. To get deeper insight of the dramatic increase, the weight percentage of chemically grafted polymer based on CF was evaluated by dissolving and removing the matrix polymer by xylene using by thermos gravimetric analysis (TGA). The chemically grafted remained polymer was found to be 0.69wt% in CF/PP, 0.98wt% in CF/MA-g-PP/PP, 1.51wt% in Pvozo coated CF/MA-g-PP/PP, suggesting that monolayer Pvozo contributed to the increase of the grafted polymer amount. In addition, the very strong adhesion by Pvozo was confirmed by observing the fractured cross-sectional surface of the composite by scanning electron micrograph (SEM). As a conclusion, the effectiveness of a highly reactive monolayer Pvozo on CF for the enhancement of the mechanical properties of CF/PP composite was demonstrated, which can be interpreted by the clear evidence of the increase of the grafting polymer on CF.

Keywords: CFRTP, interface, oxazoline, polymer graft, mechanical property

Procedia PDF Downloads 204
209 Spatial Patterns of Urban Expansion in Kuwait City between 1989 and 2001

Authors: Saad Algharib, Jay Lee

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Urbanization is a complex phenomenon that occurs during the city’s development from one form to another. In other words, it is the process when the activities in the land use/land cover change from rural to urban. Since the oil exploration, Kuwait City has been growing rapidly due to its urbanization and population growth by both natural growth and inward immigration. The main objective of this study is to detect changes in urban land use/land cover and to examine the changing spatial patterns of urban growth in and around Kuwait City between 1989 and 2001. In addition, this study also evaluates the spatial patterns of the changes detected and how they can be related to the spatial configuration of the city. Recently, the use of remote sensing and geographic information systems became very useful and important tools in urban studies because of the integration of them can allow and provide the analysts and planners to detect, monitor and analyze the urban growth in a region effectively. Moreover, both planners and users can predict the trends of the growth in urban areas in the future with remotely sensed and GIS data because they can be effectively updated with required precision levels. In order to identify the new urban areas between 1989 and 2001, the study uses satellite images of the study area and remote sensing technology for classifying these images. Unsupervised classification method was applied to classify images to land use and land cover data layers. After finishing the unsupervised classification method, GIS overlay function was applied to the classified images for detecting the locations and patterns of the new urban areas that developed during the study period. GIS was also utilized to evaluate the distribution of the spatial patterns. For example, Moran’s index was applied for all data inputs to examine the urban growth distribution. Furthermore, this study assesses if the spatial patterns and process of these changes take place in a random fashion or with certain identifiable trends. During the study period, the result of this study indicates that the urban growth has occurred and expanded 10% from 32.4% in 1989 to 42.4% in 2001. Also, the results revealed that the largest increase of the urban area occurred between the major highways after the forth ring road from the center of Kuwait City. Moreover, the spatial distribution of urban growth occurred in cluster manners.

Keywords: geographic information systems, remote sensing, urbanization, urban growth

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208 Management of Acute Appendicitis with Preference on Delayed Primary Suturing of Surgical Incision

Authors: N. A. D. P. Niwunhella, W. G. R. C. K. Sirisena

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Appendicitis is one of the most encountered abdominal emergencies worldwide. Proper clinical diagnosis and appendicectomy with minimal post operative complications are therefore priorities. Aim of this study was to ascertain the overall management of acute appendicitis in Sri Lanka in special preference to delayed primary suturing of the surgical site, comparing other local and international treatment outcomes. Data were collected prospectively from 155 patients who underwent appendicectomy following clinical and radiological diagnosis with ultrasonography. Histological assessment was done for all the specimens. All perforated appendices were managed with delayed primary closure. Patients were followed up for 28 days to assess complications. Mean age of patient presentation was 27 years; mean pre-operative waiting time following admission was 24 hours; average hospital stay was 72 hours; accuracy of clinical diagnosis of appendicitis as confirmed by histology was 87.1%; post operative wound infection rate was 8.3%, and among them 5% had perforated appendices; 4 patients had post operative complications managed without re-opening. There was no fistula formation or mortality reported. Current study was compared with previously published data: a comparison on management of acute appendicitis in Sri Lanka vs. United Kingdom (UK). The diagnosis of current study was equally accurate, but post operative complications were significantly reduced - (current study-9.6%, compared Sri Lankan study-16.4%; compared UK study-14.1%). During the recent years, there has been an exponential rise in the use of Computerised Tomography (CT) imaging in the assessment of patients with acute appendicitis. Even though, the diagnostic accuracy without using CT, and treatment outcome of acute appendicitis in this study match other local studies as well as with data compared to UK. Therefore CT usage has not increased the diagnostic accuracy of acute appendicitis significantly. Especially, delayed primary closure may have reduced post operative wound infection rate for ruptured appendices, therefore suggest this approach for further evaluation as a safer and an effective practice in other hospitals worldwide as well.

Keywords: acute appendicitis, computerised tomography, diagnostic accuracy, delayed primary closure

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207 Beneficial Effects of Curcumin against Stress Oxidative and Mitochondrial Dysfunction Induced by Trinitrobenzene Sulphonic Acid in Colon

Authors: Souad Mouzaoui, Bahia Djerdjouri

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Oxidative stress is one of the main factors involved in the onset and chronicity of inflammatory bowel disease (IBD). In this study, we investigated the beneficial effects of a potent natural antioxidant, curcumin (Cur) on colitis and mitochondrial dysfunction in trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. Rectal instillation of the chemical irritant TNBS (30 mg kg-1) induced the disruption of distal colonic architecture and a massive inflammatory cells influx to the mucosa and submucosa layers. Under these conditions, daily administration of Cur (25 mg kg-1) efficiently decreased colitis scores in the inflamed distal colon by reducing leukocyte infiltrate as attested by reduced myeloperoxidase (MPO) activity. Moreover, the levels of nitrite, an end product of inducible NO synthase activity (iNOS) and malonyl dialdehyde (MDA), a marker of lipid peroxidation increased in a time depending manner in response to TNBS challenge. Conversely, the markers of the antioxidant pool, reduced glutathione (GSH) and catalase activity (CAT) were drastically reduced. Cur attenuated oxidative stress markers and partially restored CAT and GSH levels. Moreover, our results expanded the effect of Cur on TNBS-induced colonic mitochondrial dysfunction. In fact, TNBS induced mitochondrial swelling and lipids peroxidation. These events reflected in the opening of mitochondrial transition pore and could be an initial indication in the cascade process leading to cell death. TNBS inhibited also mitochondrial respiratory activity, caused overproduction of mitochondrial superoxide anion (O2-.) and reduced level of mitochondrial GSH. Nevertheless, Cur reduced the extent of mitochondrial oxidative stress induced by TNBS and restored colonic mitochondrial function. In conclusion, our results showed the critical role of oxidative stress in TNBS-induced colitis. They highlight the role of colonic mitochondrial dysfunction induced by TNBS, as a potential source of oxidative damages. Due to its potent antioxidant properties, Cur opens a promising therapeutic approach against oxidative inflammation in IBD.

Keywords: colitis, curcumin, mitochondria, oxidative stress, TNBS

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206 Comparative Evaluation of a Dynamic Navigation System Versus a Three-Dimensional Microscope in Retrieving Separated Endodontic Files: An in Vitro Study

Authors: Mohammed H. Karim, Bestoon M. Faraj

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Introduction: instrument separation is a common challenge in the endodontic field. Various techniques and technologies have been developed to improve the retrieval success rate. This study aimed to compare the effectiveness of a Dynamic Navigation System (DNS) and a three-dimensional microscope in retrieving broken rotary NiTi files when using trepan burs and the extractor system. Materials and Methods: Thirty maxillary first bicuspids with sixty separate roots were split into two comparable groups based on a comprehensive Cone-Beam Computed Tomography (CBCT) analysis of the root length and curvature. After standardised access opening, glide paths, and patency attainment with the K file (sizes 10 and 15), the teeth were arranged on 3D models (three per quadrant, six per model). Subsequently, controlled-memory heat-treated NiTi rotary files (#25/0.04) were notched 4 mm from the tips and fractured at the apical third of the roots. The C-FR1 Endo file removal system was employed under both guidance to retrieve the fragments, and the success rate, canal aberration, treatment time and volumetric changes were measured. The statistical analysis was performed using IBM SPSS software at a significance level of 0.05. Results: The microscope-guided group had a higher success rate than the DNS guidance, but the difference was insignificant (p > 0.05). In addition, the microscope-guided drills resulted in a substantially lower proportion of canal aberration, required less time to retrieve the fragments and caused a minor change in the root canal volume (p < 0.05). Conclusion: Although dynamically guided trephining with the extractor can retrieve separated instruments, it is inferior to three-dimensional microscope guidance regarding treatment time, procedural errors, and volume change.

Keywords: dynamic navigation system, separated instruments retrieval, trephine burs and extractor system, three-dimensional video microscope

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205 The Political Economy of Conservation at Bhitarkanika Wild Life Sanctuary, India: Conflicts, Sustainability, and Development

Authors: Diptimayee Nayak, V. Upadhyay

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This paper posits the attempt of conservation and the idea of protected areas from the Marxian primitive accumulation to the politics of sustainability. Using field survey data and secondary literature, this paper analyses an Indian wildlife sanctuary, the Bhitarkanika, Odisha and finds how the hegemony of power among different management regimes attempted for conservation and the present protected area management regime attempted to imbibe the policy of ecotourism for achieving sustainability. The paper contends that the current policy of ecotourism in protected areas acts as a veil for the local deprived people, to avoid many legal conflicts like property rights, livelihood, and man-wildlife issues. Moreover, opening the scope to accumulate on the part of tour operators, the policy of ecotourism establishes a nexus between the profit holders/tour operators (the capitalists) and the power hegemony on the part of management authorities. The sustainability attempt of ecotourism may lead to private benefits maximising the profit accumulation and can expand and continue, showing the bulk of employment generation of local people at petty odd jobs, grabbing a lion share! Positing ecotourism as a capitalist project as against the general assumption of one of the drivers of sustainable development, the paper shows that ecotourism in practice may end up ruining the very social-environmental set up, leading to unsustainability related to waste management, equality, culture, relationship and above all polarised private accumulators in absence of sound mechanism. The paper ends with the caveat that while shopping for neoliberal conservation, the conservators found ecotourism as a product without finalising the hallmark of mechanism/ institutions with appropriate modus operandii to check/guard the quality assurance/standard of ecotourism for sustainability. The paper proposes sound structural and institutional mechanism of ecotourism to be developed to harness sustainability in the local economy as well as in conservation.

Keywords: conservation, ecotourism, Marxian capitalism, protected areas, sustainability

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204 Improving Cleanability by Changing Fish Processing Equipment Design

Authors: Lars A. L. Giske, Ola J. Mork, Emil Bjoerlykhaug

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The design of fish processing equipment greatly impacts how easy the cleaning process for the equipment is. This is a critical issue in fish processing, as cleaning of fish processing equipment is a task that is both costly and time consuming, in addition to being very important with regards to product quality. Even more, poorly cleaned equipment could in the worst case lead to contaminated product from which consumers could get ill. This paper will elucidate how equipment design changes could improve the work for the cleaners and saving money for the fish processing facilities by looking at a case for product design improvements. The design of fish processing equipment largely determines how easy it is to clean. “Design for cleaning” is the new hype in the industry and equipment where the ease of cleaning is prioritized gets a competitive advantage over equipment in which design for cleaning has not been prioritized. Design for cleaning is an important research area for equipment manufacturers. SeaSide AS is doing continuously improvements in the design of their products in order to gain a competitive advantage. The focus in this paper will be conveyors for internal logistic and a product called the “electro stunner” will be studied with regards to “Design for cleaning”. Often together with SeaSide’s customers, ideas for new products or product improvements are sketched out, 3D-modelled, discussed, revised, built and delivered. Feedback from the customers is taken into consideration, and the product design is revised once again. This loop was repeated multiple times, and led to new product designs. The new designs sometimes also cause the manufacturing processes to change (as in going from bolted to welded connections). Customers report back that the concrete changes applied to products by SeaSide has resulted in overall more easily cleaned equipment. These changes include, but are not limited to; welded connections (opposed to bolted connections), gaps between contact faces, opening up structures to allow cleaning “inside” equipment, and generally avoiding areas in which humidity and water may gather and build up. This is important, as there will always be bacteria in the water which will grow if the area never dries up. The work of creating more cleanable design is still ongoing, and will “never” be finished as new designs and new equipment will have their own challenges.

Keywords: cleaning, design, equipment, fish processing, innovation

Procedia PDF Downloads 235
203 MIMO Radar-Based System for Structural Health Monitoring and Geophysical Applications

Authors: Davide D’Aria, Paolo Falcone, Luigi Maggi, Aldo Cero, Giovanni Amoroso

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The paper presents a methodology for real-time structural health monitoring and geophysical applications. The key elements of the system are a high performance MIMO RADAR sensor, an optical camera and a dedicated set of software algorithms encompassing interferometry, tomography and photogrammetry. The MIMO Radar sensor proposed in this work, provides an extremely high sensitivity to displacements making the system able to react to tiny deformations (up to tens of microns) with a time scale which spans from milliseconds to hours. The MIMO feature of the system makes the system capable of providing a set of two-dimensional images of the observed scene, each mapped on the azimuth-range directions with noticeably resolution in both the dimensions and with an outstanding repetition rate. The back-scattered energy, which is distributed in the 3D space, is projected on a 2D plane, where each pixel has as coordinates the Line-Of-Sight distance and the cross-range azimuthal angle. At the same time, the high performing processing unit allows to sense the observed scene with remarkable refresh periods (up to milliseconds), thus opening the way for combined static and dynamic structural health monitoring. Thanks to the smart TX/RX antenna array layout, the MIMO data can be processed through a tomographic approach to reconstruct the three-dimensional map of the observed scene. This 3D point cloud is then accurately mapped on a 2D digital optical image through photogrammetric techniques, allowing for easy and straightforward interpretations of the measurements. Once the three-dimensional image is reconstructed, a 'repeat-pass' interferometric approach is exploited to provide the user of the system with high frequency three-dimensional motion/vibration estimation of each point of the reconstructed image. At this stage, the methodology leverages consolidated atmospheric correction algorithms to provide reliable displacement and vibration measurements.

Keywords: interferometry, MIMO RADAR, SAR, tomography

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202 The Spatial Pattern of Economic Rents of an Airport Development Area: Lessons Learned from the Suvarnabhumi International Airport, Thailand

Authors: C. Bejrananda, Y. Lee, T. Khamkaew

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With the rise of the importance of air transportation in the 21st century, the role of economics in airport planning and decision-making has become more important to the urban structure and land value around it. Therefore, this research aims to examine the relationship between an airport and its impacts on the distribution of urban land uses and land values by applying the Alonso’s bid rent model. The New Bangkok International Airport (Suvarnabhumi International Airport) was taken as a case study. The analysis was made over three different time periods of airport development (after the airport site was proposed, during airport construction, and after the opening of the airport). The statistical results confirm that Alonso’s model can be used to explain the impacts of the new airport only for the northeast quadrant of the airport, while proximity to the airport showed the inverse relationship with the land value of all six types of land use activities through three periods of time. It indicates that the land value for commercial land use is the most sensitive to the location of the airport or has the strongest requirement for accessibility to the airport compared to the residential and manufacturing land use. Also, the bid-rent gradients of the six types of land use activities have declined dramatically through the three time periods because of the Asian Financial Crisis in 1997. Therefore, the lesson learned from this research concerns about the reliability of the data used. The major concern involves the use of different areal units for assessing land value for different time periods between zone block (1995) and grid block (2002, 2009). As a result, this affect the investigation of the overall trends of land value assessment, which are not readily apparent. In addition, the next concern is the availability of the historical data. With the lack of collecting historical data for land value assessment by the government, some of data of land values and aerial photos are not available to cover the entire study area. Finally, the different formats of using aerial photos between hard-copy (1995) and digital photo (2002, 2009) made difficult for measuring distances. Therefore, these problems also affect the accuracy of the results of the statistical analyses.

Keywords: airport development area, economic rents, spatial pattern, suvarnabhumi international airport

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201 Effective Medium Approximations for Modeling Ellipsometric Responses from Zinc Dialkyldithiophosphates (ZDDP) Tribofilms Formed on Sliding Surfaces

Authors: Maria Miranda-Medina, Sara Salopek, Andras Vernes, Martin Jech

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Sliding lubricated surfaces induce the formation of tribofilms that reduce friction, wear and prevent large-scale damage of contact parts. Engine oils and lubricants use antiwear and antioxidant additives such as zinc dialkyldithiophosphate (ZDDP) from where protective tribofilms are formed by degradation. The ZDDP tribofilms are described as a two-layer structure composed of inorganic polymer material. On the top surface, the long chain polyphosphate is a zinc phosphate and in the bulk, the short chain polyphosphate is a mixed Fe/Zn phosphate with a gradient concentration. The polyphosphate chains are partially adherent to steel surface through a sulfide and work as anti-wear pads. In this contribution, ZDDP tribofilms formed on gray cast iron surfaces are studied. The tribofilms were generated in a reciprocating sliding tribometer with a piston ring-cylinder liner configuration. Fully formulated oil of SAE grade 5W-30 was used as lubricant during two tests at 40Hz and 50Hz. For the estimation of the tribofilm thicknesses, spectroscopic ellipsometry was used due to its high accuracy and non-destructive nature. Ellipsometry works under an optical principle where the change in polarisation of light reflected by the surface, is associated with the refractive index of the surface material or to the thickness of the layer deposited on top. Ellipsometrical responses derived from tribofilms are modelled by effective medium approximation (EMA), which includes the refractive index of involved materials, homogeneity of the film and thickness. The materials composition was obtained from x-ray photoelectron spectroscopic studies, where the presence of ZDDP, O and C was confirmed. From EMA models it was concluded that tribofilms formed at 40 Hz are thicker and more homogeneous than the ones formed at 50 Hz. In addition, the refractive index of each material is mixed to derive an effective refractive index that describes the optical composition of the tribofilm and exhibits a maximum response in the UV range, being a characteristic of glassy semitransparent films.

Keywords: effective medium approximation, reciprocating sliding tribometer, spectroscopic ellipsometry, zinc dialkyldithiophosphate

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200 Drug and Poison Information Centers: An Emergent Need of Health Care Professionals in Pakistan

Authors: Asif Khaliq, Sayeeda A. Sayed

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The drug information centers provide drug related information to the requesters that include physicians, pharmacist, nurses and other allied health care professionals. The International Pharmacist Federation (FIP) describes basic functions of a drug and poison information centers as drug evaluation, therapeutic counseling, pharmaceutical advice, research, pharmaco-vigilence and toxicology. Continuous advancement in the field of medicine has expanded the medical literature, which has increased demand of a drug and poison information center for the guidance, support and facilitation of physicians. The objective of the study is to determine the need of drug and poison information centers in public and private hospitals of Karachi, Pakistan. A cross sectional study was conducted during July 2013 to April 2014 using a self-administered, multi-itemed questionnaire. Non Probability Convenient sampling was used to select the study participants. A total of 307 physicians from public and private hospitals of Karachi participated in the study. The need for 24/7 Drug and poison information center was highlighted by 92 % of physicians and 67% physicians suggested opening a drug information center at the hospital. It was reported that 70% physicians take at least 15 minutes for searching the information about the drug while managing a case. Regarding the poisoning case management, 52% physicians complaint about the unavailability of medicines in hospitals; and mentioned the importance of medicines for safe and timely management of patients. Although 73% physicians attended continued medical education (CME) sessions, 92 % physicians insisted on the need of 24/7 Drug and poison information center. The scarcity of organized channel for obtaining the information about drug and poisons is one of the most crucial problems for healthcare workers in Pakistan. The drug and poison information center is an advisory body that assists health care professional and patients in provision of appropriate drug and hazardous substance information. Drug and poison information center is one of the integral needs for running an effective health care system. Provision of a 24 /7 drug information centers with specialized staff offer multiple benefits to the hospitals while reducing treatment delays, addressing awareness gaps of all stakeholders and ensuring provision of quality health care.

Keywords: drug and poison information centers, Pakistan, physicians, public and private hospitals

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199 Characterization of Articular Cartilage Based on the Response of Cartilage Surface to Loading/Unloading

Authors: Z. Arabshahi, I. Afara, A. Oloyede, H. Moody, J. Kashani, T. Klein

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Articular cartilage is a fluid-swollen tissue of synovial joints that functions by providing a lubricated surface for articulation and to facilitate the load transmission. The biomechanical function of this tissue is highly dependent on the integrity of its ultrastructural matrix. Any alteration of articular cartilage matrix, either by injury or degenerative conditions such as osteoarthritis (OA), compromises its functional behaviour. Therefore, the assessment of articular cartilage is important in early stages of degenerative process to prevent or reduce further joint damage with associated socio-economic impact. Therefore, there has been increasing research interest into the functional assessment of articular cartilage. This study developed a characterization parameter for articular cartilage assessment based on the response of cartilage surface to loading/unloading. This is because the response of articular cartilage to compressive loading is significantly depth-dependent, where the superficial zone and underlying matrix respond differently to deformation. In addition, the alteration of cartilage matrix in the early stages of degeneration is often characterized by PG loss in the superficial layer. In this study, it is hypothesized that the response of superficial layer is different in normal and proteoglycan depleted tissue. To establish the viability of this hypothesis, samples of visually intact and artificially proteoglycan-depleted bovine cartilage were subjected to compression at a constant rate to 30 percent strain using a ring-shaped indenter with an integrated ultrasound probe and then unloaded. The response of articular surface which was indirectly loaded was monitored using ultrasound during the time of loading/unloading (deformation/recovery). It was observed that the rate of cartilage surface response to loading/unloading was different for normal and PG-depleted cartilage samples. Principal Component Analysis was performed to identify the capability of the cartilage surface response to loading/unloading, to distinguish between normal and artificially degenerated cartilage samples. The classification analysis of this parameter showed an overlap between normal and degenerated samples during loading. While there was a clear distinction between normal and degenerated samples during unloading. This study showed that the cartilage surface response to loading/unloading has the potential to be used as a parameter for cartilage assessment.

Keywords: cartilage integrity parameter, cartilage deformation/recovery, cartilage functional assessment, ultrasound

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198 An In-Depth Comparison Study of Canadian and Danish's Entrepreneurship and Education System

Authors: Amna Khaliq

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In this research paper, a comparison study has been undertaken between Canada and Denmark to analyze the education system between the countries in entrepreneurship. Denmark, a land of high wages and high taxes, and Canada, a land of immigrants and opportunities, have seen a positive relationship in entrepreneurs' growth. They are both considered one of the top ten countries to start a business and to have government support globally. However, education is entirely free to Danish students, including university degrees, compared to Canadians, which can further hurdle for Canadian millennials to grow in the business world—the business experience more growth with educated entrepreneurs with international backgrounds in new immigrants. Denmark has seen a gradual increase in female entrepreneurs over the decade but is still lower than OECD countries. Compassionate management and work-life balance are prioritized in Denmark, unlike in Canada. Danish are early adopters of technology and have excellent infrastructure to support the technology industry, whereas Canada is still a service-oriented and manufacturer-based country. 2018 has been the highest number of opening businesses for Canada and Denmark. Some companies offer high wages, hiring bonuses, flexible working hours, wellness, and mental health benefits during Pandemic to keep the companies running and keep their workers' morale high. Pandemic has taught consumers new patterns to shop online. It is essential now to use technology and automation to increase productivity in businesses. Only those companies will survive that are applying this strategy. The Pandemic has ultimately changed entrepreneurs' and employees' behavior in the business world. Along with Ph.D. professors, entrepreneurs should be allowed to teach at learning intuitions. Millennials turn out to be the most entrepreneurial generation in both countries. Entrepreneurship education will only be beneficial when students create businesses and learn from real-life experiences. Managing physical, mental, emotional, and psychological health while dealing with high pressure in entrepreneurship are soft skills learned through practical work.

Keywords: entrepreneurship education, millennials, pandemic, Denmark, Canada

Procedia PDF Downloads 101
197 Synthesis and Analgesic activity of 2-(p-Substituted phenyl)-3-[4-(N-Substituted amino) methyl-2-oxo indoilin-3-ylidene]benzenesulfonyl Quinazolin-4(3H)-One Derivatives

Authors: N. Gopal, K. Jaasminerjiit, L. Z. Xiang

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Quinazoline-4(3H)-one ring system has been consistently regarded as promising privileged structural icon owing to its pharmacodynamic versatility in many of its synthetic derivatives as well as in several naturally occurring alkaloids. The literature reveals that 2nd & 3rd positions of the quinazolin-4(3H)-one pharmacophore are the target for substitution with other moieties. On the other hand, sulphanilamide derivatives and isatin moiety also displayed valuable biological activities. Hence, it was thought worthwhile to study the effects of three pharmacophoric moieties like quinazolinone, sulphanilamide and isatin in a single molecule for the better analgesic activity with lower toxicity. Series of novel 2,3-disubstituted quinazolin-4(3H)-one derivatives have been synthesised from the intermediate Schiff base of 2-(4’-substitutedphenyl)-3-[(N-2-oxoindolin-3-ylidene)-4”-sulphonamidophenyl]-quinazolin-4(3H)-one derivatives, which was prepared from reacting 2-(substituted phenyl)-4H-benzo[d][1,3]-oxazin-4-one with sulphanilamide. The required benzoxazinone derivatives were prepared by reacting anthranilic acid with benzoyl chloride. All the compounds structure was characterised by using H1 NMR, IR and Mass spectroscopy. The intermediate Schiff base and final Mannich base compounds were evaluated for their analgesic activity by acetic acid-induced writhing method at the dose of 25mg/kg, 50 mg/kg, and 100 mg/kg (bw) and Diclofenac (25mg/kg of body weight) will be used as the reference drugs. From the results of the study, it has been observed that final Mannich base showed a better analgesic activity when compared to the parent Schiff bases, it was found that compound substituted with N-methyl piperazine at 1st position of the indole nucleus of the final quinazolinone derivatives (GA4B1) i.e. 2-(4’-methoxy phenyl)-3-[4-(N-(1-N-methyl piperazine amine) methyl-2-oxo indoilin-3-ylidene] benzenesulfonyl quinazolin-4(3H)-one increases the analgesic activity and among the synthesised compounds, GA4B1 exhibited quite superior analgesic activity. The remaining Schiff bases and Mannich base derivatives exhibited moderate analgesic activity. All the compounds showed a dose dependent activity. None of the synthesised compound showed ulcer index whereas the standard drug, diclofenac [25 mg/kg (bw)] showed significantly higher gross ulcer index values.

Keywords: analgesic activity, isatin, mannich base, quinazolin-4(3H)-one

Procedia PDF Downloads 339
196 The Ratio of Second to Fourth Digit Length Correlates with Cardiorespiratory Fitness in Male College Students Men but Not in Female

Authors: Cheng-Chen Hsu

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Background: The ratio of the length of the second finger (index finger, 2D) to the fourth finger (ring finger, 4D) (2D:4D) is a putative marker of prenatal hormones. A low 2D:4D ratio is related to high prenatal testosterone (PT) levels. Physiological research has suggested that a low 2D:4D ratio is correlated with high sports ability. Aim: To examine the association between cardiorespiratory fitness and 2D:4D. Methods: Assessment of 2D:4D; Images of hands were collected from participants using a computer scanner. Hands were placed lightly on the surface of the plate. Image analysis was performed using Image-Pro Plus 5.0 software. Feature points were marked at the tip of the finger and at the center of the proximal crease on the second and fourth digits. Actual measurement was carried out automatically, 2D:4D was calculated by dividing 2nd by 4th digit length. YMCA 3-min Step Test; The test involves stepping up and down at a rate of 24 steps/min for 3 min; a tape recording of the correct cadence (96 beats/min) is played to assist the participant in keeping the correct pace. Following the step test, the participant immediately sits down and, within 5 s, the tester starts counting the pulse for 1 min. The score for the test, the total 1-min postexercise heart rate, reflects the heart’s ability to recover quickly. Statistical Analysis ; Pearson’s correlation (r) was used for assessing the relationship between age, physical measurements, one-minute heart rate after YMCA 3-minute step test (HR) and 2D:4D. An independent-sample t-test was used for determining possible differences in HR between subjects with low and high values of 2D:4D. All statistical analyses were carried out with SPSS 18 for Window. All P-values were two-tailed at P = 0.05, if not reported otherwise. Results: A median split by 2D:4D was applied, resulting in a high and a low group. One-minute heart rate after YMCA 3-minute step test was significantly difference between groups of male right-hand 2D:4D (p = 0.024). However, no difference in left-hand 2D:4D values between groups in male, and no digit ratio difference between groups in female. Conclusion: The results showed that cardiopulmonary fitness is related to right 2D:4D, only in men. We argue that prenatal testosterone may have an effect on cardiorespiratory fitness in male but not in female.

Keywords: college students, digit ratio, finger, step test, fitness

Procedia PDF Downloads 268
195 Cross-Sectional Analysis of Partner Support and Contraceptive Use in Adolescent Females

Authors: Ketan Tamirisa, Kathleen P. Tebb

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In the U.S., annually, there are over 1 million pregnancies in teenagers and most (85%) are unintended. The need for proactive prevention measures is imperative to support adolescents with their pregnancy prevention and family planning goals. To date, there is limited research examining the extent to which support from a sexual partner(s) influences contraceptive use. To address this gap, this study assessed the relationship between sexually active adolescents, sex-assigned birth as female, and their perceived support from their sexual partner(s) about their contraceptive use in the last three months. Baseline data from sexually active adolescent females, between 13-19 years who were not currently using a long-acting contraceptive device, were recruited from 32 school-based health centers (SBHCs) in seven states in the U.S. as part of a larger study to evaluate Health-E You/ Salud iTuTM, a web-based contraceptive decision support tool. Fisher’s exact test assessed the cross-sectional association between perceived sexual partner support of contraceptive use in the past three months (felt no support, felt little support, and felt a lot of support), and current use of non-barrier contraception. A total of 91 sexually active adolescent females were eligible and completed the baseline survey. The mean age was 16.7 and nearly half (49.3%) were Hispanic/Latina. Most (85.9%) indicated it was very important to avoid becoming pregnant. A total of 60 participants (65.9%) reported use of non-barrier contraception. Of these, most used birth control pills (n=26), followed by Depo-Provera injection (n=12), patch (n=1), and ring (n=1). Most of the participants (80.2%) indicated that they perceived a lot of support from their partners and 19.8% reported no or little support. Among those reporting a lot of support, 69.9% (51/73) reported current use of non-barrier contraception compared to 50% (9/18) who felt no/little support and reported contraceptive use. This difference approached but did not reach statistical significance (p=0.096). Results from this preliminary data indicate that many adolescents who are coming in for care at SBHCs are at risk of unintended pregnancy. Many participants also reported a lot of support from their sexual partner(s) to use contraception. While the associations only approached significance, this is likely due to the small sample size. This and future research can better understand this association to inform interventions aimed at sexual partners to strengthen education and social support, increase healthcare accessibility, and ultimately reduce rates of unintended pregnancy.

Keywords: adolescents, contraception, pregnancy, SBHCs, sexual partners

Procedia PDF Downloads 39
194 Poly(propylene fumarate) Copolymers with Phosphonic Acid-based Monomers Designed as Bone Tissue Engineering Scaffolds

Authors: Görkem Cemali̇, Avram Aruh, Gamze Torun Köse, Erde Can ŞAfak

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In order to heal bone disorders, the conventional methods which involve the use of autologous and allogenous bone grafts or permanent implants have certain disadvantages such as limited supply, disease transmission, or adverse immune response. A biodegradable material that acts as structural support to the damaged bone area and serves as a scaffold that enhances bone regeneration and guides bone formation is one desirable solution. Poly(propylene fumarate) (PPF) which is an unsaturated polyester that can be copolymerized with appropriate vinyl monomers to give biodegradable network structures, is a promising candidate polymer to prepare bone tissue engineering scaffolds. In this study, hydroxyl-terminated PPF was synthesized and thermally cured with vinyl phosphonic acid (VPA) and diethyl vinyl phosphonate (VPES) in the presence of radical initiator benzoyl peroxide (BP), with changing co-monomer weight ratios (10-40wt%). In addition, the synthesized PPF was cured with VPES comonomer at body temperature (37oC) in the presence of BP initiator, N, N-Dimethyl para-toluidine catalyst and varying amounts of Beta-tricalcium phosphate (0-20 wt% ß-TCP) as filler via radical polymerization to prepare composite materials that can be used in injectable forms. Thermomechanical properties, compressive properties, hydrophilicity and biodegradability of the PPF/VPA and PPF/VPES copolymers were determined and analyzed with respect to the copolymer composition. Biocompatibility of the resulting polymers and their composites was determined by the MTS assay and osteoblast activity was explored with von kossa, alkaline phosphatase and osteocalcin activity analysis and the effects of VPA and VPES comonomer composition on these properties were investigated. Thermally cured PPF/VPA and PPF/VPES copolymers with different compositions exhibited compressive modulus and strength values in the wide range of 10–836 MPa and 14–119 MPa, respectively. MTS assay studies showed that the majority of the tested compositions were biocompatible and the overall results indicated that PPF/VPA and PPF/VPES network polymers show significant potential for applications as bone tissue engineering scaffolds where varying PPF and co-monomer ratio provides adjustable and controllable properties of the end product. The body temperature cured PPF/VPES/ß-TCP composites exhibited significantly lower compressive modulus and strength values than the thermal cured PPF/VPES copolymers and were therefore found to be useful as scaffolds for cartilage tissue engineering applications.

Keywords: biodegradable, bone tissue, copolymer, poly(propylene fumarate), scaffold

Procedia PDF Downloads 164
193 Electromagnetic Energy Harvesting by Using a Rectenna with a Metamaterial Lens

Authors: Ursula D. C. Resende, Fabiano S. Bicalho, Sandro T. M. Gonçalves

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The growing demand for cheap and clean energy sources have been motivated by the study and development of distinct technologies and devices able to provide different amounts of energy. In order to supply energy for small loads, the energy from the electromagnetic spectrum can be harvested. This possibility is particularly interesting because this kind of energy is constantly available in the environment and the number of radiofrequency sources is permanently increasing, due to advances in telecommunications services. A rectenna, which is a combination of an antenna and a rectifier circuit, is an equipment that can efficiently perform the electromagnetic energy harvesting. However, since the amount of electromagnetic energy available in the environment is very small, limited values of power can be harvested by the rectenna. Therefore, several technical strategies have been investigated in order to increase this amount of power. In this work, a metamaterial electromagnetic lens is used to improve the electromagnetic energy harvesting. The rectenna investigated was designed and optimized to charge a Li-Ion battery using the electromagnetic energy from an internet Wi-Fi commercial router model TL-WR841HP operating in 2.45 GHz with maximal output power equal to 18 dBm. The rectenna consists of a high directive antenna, a double voltage rectifier circuit and a metamaterial lens. The printed antenna, constituted of two rectangular radiator elements, was projected and optimized by using the Computer Simulation Software (CST) in order to obtain high directivities and values of S11 parameter below -10 dB in 2.45 GHz. The antenna was printed over a double-sided copper fiberglass substrate, FR4, with characterized relative electric permittivity εr = 4.3 and tangent of losses δ = 0.01. The rectifier circuit, which incorporates a circuit for impedance matching and uses the Schottky diode HSMS-2852, was projected and optimized by using Advanced Design Software (ADS) and built over the same FR4 substrate. The metamaterial cell is composed of two Square Split Ring Resonator (S-SRR) and a thin wire in order to operate with negative values of εr and relative magnetic permeability in 2.45 GHz. In order to evaluate the performance of the purposed rectenna two experimental charging tests were performed, one without and other with the metamaterial lens. The result obtained demonstrate that the electromagnetic lens was able to significantly increase the levels of electric current delivered to the battery, approximately 44%.

Keywords: electromagnetic energy harvesting, electromagnetic lens, metamaterial, rectenna

Procedia PDF Downloads 138
192 Septin 11, Cytoskeletal Protein Involved in the Regulation of Lipid Metabolism in Adipocytes

Authors: Natalia Moreno-Castellanos, Amaia Rodriguez, Gema Frühbeck

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Introduction: In adipocytes, the cytoskeleton undergoes important expression and distribution in adipocytes rearrangements during adipogenesis and in obesity. Indeed, a role for these proteins in the regulation of adipocyte differentiation and response to insulin has been demonstrated. Recently, septins have been considered as new components of the cytoskeletal network that interact with other cytoskeletal elements (actin and tubulin) profoundly modifying their dynamics. However, these proteins have not been characterized as yet in adipose tissue. In this work, were examined the cellular, molecular and functional features of a member of this family, septin 11 (SEPT11), in adipocytes and evaluated the impact of obesity on the expression of this protein in human adipose tissue. Methods: Adipose gene and protein expression levels of SEPT11 were analysed in human samples. SEPT11 distribution was evaluated by immunocytochemistry, electronic microscopy, and subcellular fractionation techniques. GST-pull down, immunoprecipitation and a Yeast-Two Hybrid (Y2H) screening were used to identify the SEPT11 interactome. Gene silencing was employed to assess the role of SEPT11 in the regulation of insulin signaling and lipid metabolism in adipocytes. Results: SEPT11 is expressed in human adipocytes, and its levels increased in both omental and subcutaneous adipose tissue in obesity, with SEPT11 mRNA content positively correlating with parameters of insulin resistance in subcutaneous fat. In non-stimulated adipocytes, SEPT11 immunoreactivity showed a ring-like distribution at the cell surface and associated to caveolae. Biochemical analyses showed that SEPT11 interacted with the main component of caveolae, caveolin-1 (CAV1) as well as with the fatty acid-binding protein, FABP5. Notably, the three proteins redistributed and co-localized at the surface of lipid droplets upon exposure of adipocytes to oleate. In this line, SEPT11 silencing in 3T3-L1 adipocytes impaired insulin signaling and decreased insulin-induced lipogenesis. Conclusions: Those findings demonstrate that SEPT11 is a novel component of the adipocyte cytoskeleton that plays an important role in the regulation of lipid traffic, metabolism and can thus represent a potential biomarker of insulin resistance in obesity in adipocytes through its interaction with both CAV1 and FABP5.

Keywords: caveolae, lipid metabolism, obesity, septins

Procedia PDF Downloads 209
191 Integration and Translation: The Comparison of Religious Rituals of Caodaism in Vietnam and Yi-Kuan-Tao

Authors: Lim Pey Huan

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In the second half of the 19th century, Vietnam has long been influenced by Han culture, so there are many similarities in religion and folk beliefs. Even after the acceptance process of the Catholic Church introduced from Europe is quite similar. Therefore, in the spiritual life of Vietnamese civil society, Confucianism, Buddhism, Taoism, Christianity, Islam, and folk beliefs can be said to be the main trend, but in the twentieth century, two indigenous new religions were born: Caodai and He Hao Jiao, both of which are produced and developed in the south, each of which has millions of believers and become important Vietnamese religions. Their political participation has a major impact on the development of the Republic of Vietnam, and their fate is also in the north and south. Significant changes have taken place after reunification. Caodai was later approved by the colonial authorities and became the third largest religion in Vietnam. The teachings of Caodai teach the ideas of the major religions of the world. The classics used in the teachings also contain important theories of various religions, with particular emphasis on the comprehensiveness of the three sects of Confucianism, Buddhism, and Taoism. The obvious manifestation lies in the interpretation of the important proposition of 'opening the three religions and returning to the five branches.' The full name of Caodaism is 'Da Dao San Qi Pu Du Gao Tai Jiao'. This name coincides with the 'Longhua Club' and the 'San Qi Mo Jie' idea and the consistent central idea. The emerging road of Caodai advocates to lead the sentient beings back to their original missions; the sentient beings will be centered on people, and the nature of the talks is nothing more than the original mission and standard. There are many opinions about the introduction of Caodaism into southern Vietnam. Caodai believers believe that Caodaism is an emerging new religion in Vietnam. If we further explore the teachings and religious rituals of Caodai, it is not difficult to find that many Chinese sects have been introduced to Vietnam. Some of the colors can be discussed from the spread and influence of Congenital Road in Vietnam. This article will present the author's analysis of the actual process of tutoring in Vietnam's Caodai, and then compare it with the consistent religious experience, trying to explore the Yi-Kuan-Tao and consistent Yi-Kuan-Tao rituals, religious organization, religious teachings, religious life care, and Funeral rituals and other comparative studies.

Keywords: Vietnam, Caodaism, Yi-Kuan-Tao, religious rituals

Procedia PDF Downloads 118
190 Identification and Characterization of in Vivo, in Vitro and Reactive Metabolites of Zorifertinib Using Liquid Chromatography Lon Trap Mass Spectrometry

Authors: Adnan A. Kadi, Nasser S. Al-Shakliah, Haitham Al-Rabiah

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Zorifertinib is a novel, potent, oral, a small molecule used to treat non-small cell lung cancer (NSCLC). zorifertinib is an Epidermal Growth Factor Receptor (EGFR) inhibitor and has good blood–brain barrier permeability for (NSCLC) patients with EGFR mutations. zorifertinibis currently at phase II/III clinical trials. The current research reports the characterization and identification of in vitro, in vivo and reactive intermediates of zorifertinib. Prediction of susceptible sites of metabolism and reactivity pathways (cyanide and GSH) of zorifertinib were performed by the Xenosite web predictor tool. In-vitro metabolites of zorifertinib were performed by incubation with rat liver microsomes (RLMs) and isolated perfused rat liver hepatocytes. Extraction of zorifertinib and it's in vitro metabolites from the incubation mixtures were done by protein precipitation. In vivo metabolism was done by giving a single oral dose of zorifertinib(10 mg/Kg) to Sprague Dawely rats in metabolic cages by using oral gavage. Urine was gathered and filtered at specific time intervals (0, 6, 12, 18, 24, 48, 72,96and 120 hr) from zorifertinib dosing. A similar volume of ACN was added to each collected urine sample. Both layers (organic and aqueous) were injected into liquid chromatography ion trap mass spectrometry(LC-IT-MS) to detect vivozorifertinib metabolites. N-methyl piperizine ring and quinazoline group of zorifertinib undergoe metabolism forming iminium and electro deficient conjugated system respectively, which are very reactive toward nucleophilic macromolecules. Incubation of zorifertinib with RLMs in the presence of 1.0 mM KCN and 1.0 Mm glutathione were made to check reactive metabolites as it is often responsible for toxicities associated with this drug. For in vitro metabolites there were nine in vitro phase I metabolites, four in vitro phase II metabolites, eleven reactive metabolites(three cyano adducts, five GSH conjugates metabolites, and three methoxy metabolites of zorifertinib were detected by LC-IT-MS. For in vivo metabolites, there were eight in vivo phase I, tenin vivo phase II metabolitesofzorifertinib were detected by LC-IT-MS. In vitro and in vivo phase I metabolic pathways wereN- demthylation, O-demethylation, hydroxylation, reduction, defluorination, and dechlorination. In vivo phase II metabolic reaction was direct conjugation of zorifertinib with glucuronic acid and sulphate.

Keywords: in vivo metabolites, in vitro metabolites, cyano adducts, GSH conjugate

Procedia PDF Downloads 193
189 The Influence of Infiltration and Exfiltration Processes on Maximum Wave Run-Up: A Field Study on Trinidad Beaches

Authors: Shani Brathwaite, Deborah Villarroel-Lamb

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Wave run-up may be defined as the time-varying position of the landward extent of the water’s edge, measured vertically from the mean water level position. The hydrodynamics of the swash zone and the accurate prediction of maximum wave run-up, play a critical role in the study of coastal engineering. The understanding of these processes is necessary for the modeling of sediment transport, beach recovery and the design and maintenance of coastal engineering structures. However, due to the complex nature of the swash zone, there remains a lack of detailed knowledge in this area. Particularly, there has been found to be insufficient consideration of bed porosity and ultimately infiltration/exfiltration processes, in the development of wave run-up models. Theoretically, there should be an inverse relationship between maximum wave run-up and beach porosity. The greater the rate of infiltration during an event, associated with a larger bed porosity, the lower the magnitude of the maximum wave run-up. Additionally, most models have been developed using data collected on North American or Australian beaches and may have limitations when used for operational forecasting in Trinidad. This paper aims to assess the influence and significance of infiltration and exfiltration processes on wave run-up magnitudes within the swash zone. It also seeks to pay particular attention to how well various empirical formulae can predict maximum run-up on contrasting beaches in Trinidad. Traditional surveying techniques will be used to collect wave run-up and cross-sectional data on various beaches. Wave data from wave gauges and wave models will be used as well as porosity measurements collected using a double ring infiltrometer. The relationship between maximum wave run-up and differing physical parameters will be investigated using correlation analyses. These physical parameters comprise wave and beach characteristics such as wave height, wave direction, period, beach slope, the magnitude of wave setup, and beach porosity. Most parameterizations to determine the maximum wave run-up are described using differing parameters and do not always have a good predictive capability. This study seeks to improve the formulation of wave run-up by using the aforementioned parameters to generate a formulation with a special focus on the influence of infiltration/exfiltration processes. This will further contribute to the improvement of the prediction of sediment transport, beach recovery and design of coastal engineering structures in Trinidad.

Keywords: beach porosity, empirical models, infiltration, swash, wave run-up

Procedia PDF Downloads 350
188 Cairo’s Inferno of Pollution: Ecocritical Reading of “The Breeze Hunter” by Egyptian Writer Mohammed Makhzangi

Authors: Mila Fantinelli

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Cairo is the perfect modern representation of a living hell between rising temperatures and failing architecture. The works of Egyptian writer Mohamed Makhzangi may prove to add more depth to the debate that surrounds the topic of pollution in Arab literature. This Egyptian writer, who studied medicine and psychiatry before dedicating his life to writing, sheds indeed further light on the ecological condition of Cairo. In relation to this, the short story “The breeze hunter” (2018) tackles the topic of “environmental architecture”, citing the research of Hassan Fathy in “Architecture for the Poor: An Experiment in Rural Egypt” which provides examples from history of inventions to counter the effects of the hot weather. Specifically, the main character of the story is a man living in Cairo in a small apartment, which turns into a living hell in the summer season because of the high temperatures. Catastrophic urban planning, therefore, prevents the mitigation of the torrid climate but rather worsens it. Makhzangi indeed refers to the environmental issue of pollution caused by the excessive number of air conditioners, which transform Cairo into an infernal island of heat while our country becomes warmer with the passing of time. His description of the city already intersects ecocriticism and environmental issues, tackling the topic of pollution inside of cities and the impact of climate change, of which Cairo is a perfect example. History has indeed provided ways in order to reduce the heat inside houses. Yet, these have all been ignored. As a result, through the teachings of Hassan Fathy, the narrator of the story builds an opening in the house to catch the natural breeze coming from the north. He, therefore, becomes the breeze hunter of Mansoura. However, polluted waves interrupt this brief rest, thus leading to a worsening of his conditions, leading to him suffering from the effects of crowding and the consequences of climate change and pollution. Makhzangi, therefore, reflects on how architecture and urbanism affect the psychological sanity of people and how the situation is worsened by the catastrophic consequences of climate change and pollution.

Keywords: ecocriticism, Arabic literature, pollution, environmental architecture, crowding

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187 Liquid Unloading of Wells with Scaled Perforation via Batch Foamers

Authors: Erwin Chan, Aravind Subramaniyan, Siti Abdullah Fatehah, Steve Lian Kuling

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Foam assisted lift technology is proven across the industry to provide efficient deliquification in gas wells. Such deliquification is typically achieved by delivering the foamer chemical downhole via capillary strings. In highly liquid loaded wells where capillary strings are not readily available, foamer can be delivered via batch injection or bull-heading. The latter techniques differ from the former in that cap strings allow for liquid to be unloaded continuously, whereas foamer batches require that periodic batching be conducted for the liquid to be unloaded. Although batch injection allows for liquid to be unloaded in wells with suitable water to gas (WGR) ratio and condensate to gas (CGR) ratio without well intervention for capillary string installation, this technique comes with its own set of challenges - for foamer to de-liquify liquids, the chemical needs to reach perforation locations where gas bubbling is observed. In highly scaled perforation zones in certain wells, foamer delivered in batches is unable to reach the gas bubbling zone, thus achieving poor lift efficiency. This paper aims to discuss the techniques and challenges for unloading liquid via batch injection in scaled perforation wells X and Y, whose WGR is 6bbl/MMscf, whose scale build-up is observed at the bottom of perforation interval, whose water column is 400 feet, and whose ‘bubbling zone’ is less than 100 feet. Variables such as foamer Z dosage, batching technique, and well flow control valve opening times are manipulated during the duration of the trial to achieve maximum liquid unloading and gas rates. During the field trial, the team has found optimal values between the three aforementioned parameters for best unloading results, in which each cycle’s gas and liquid rates are compared with baselines with similar flowing tubing head pressures (FTHP). It is discovered that amongst other factors, a good agitation technique is a primary determinant for efficient liquid unloading. An average increment of 2MMscf/d against an average production of 4MMscf/d at stable FTHP is recorded during the trial.

Keywords: foam, foamer, gas lift, liquid unloading, scale, batch injection

Procedia PDF Downloads 178
186 A Simulation-Based Study of Dust Ingression into Microphone of Indoor Consumer Electronic Devices

Authors: Zhichao Song, Swanand Vaidya

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Nowadays, most portable (e.g., smartphones) and wearable (e.g., smartwatches and earphones) consumer hardware are designed to be dustproof following IP5 or IP6 ratings to ensure the product is able to handle potentially dusty outdoor environments. On the other hand, the design guideline is relatively vague for indoor devices (e.g., smart displays and speakers). While it is generally believed that the indoor environment is much less dusty, in certain circumstances, dust ingression is still able to cause functional failures, such as microphone frequency response shift and camera black spot, or cosmetic dissatisfaction, mainly the dust build up in visible pockets and gaps which is hard to clean. In this paper, we developed a simulation methodology to analyze dust settlement and ingression into known ports of a device. A closed system is initialized with dust particles whose sizes follow Weibull distribution based on data collected in a user study, and dust particle movement was approximated as a settlement in stationary fluid, which is governed by Stokes’ law. Following this method, we simulated dust ingression into MEMS microphone through the acoustic port and protective mesh. Various design and environmental parameters are evaluated including mesh pore size, acoustic port depth-to-diameter ratio, mass density of dust material and inclined angle of microphone port. Although the dependencies of dust resistance on these parameters are all monotonic, smaller mesh pore size, larger acoustic depth-to-opening ratio and more inclined microphone placement (towards horizontal direction) are preferred for dust resistance; these preferences may represent certain trade-offs in audio performance and compromise in industrial design. The simulation results suggest the quantitative ranges of these parameters, with more pronounced effects in the improvement of dust resistance. Based on the simulation results, we proposed several design guidelines that intend to achieve an overall balanced design from audio performance, dust resistance, and flexibility in industrial design.

Keywords: dust settlement, numerical simulation, microphone design, Weibull distribution, Stoke's equation

Procedia PDF Downloads 104
185 Experimental Study and Numerical Modelling of Failure of Rocks Typical for Kuzbass Coal Basin

Authors: Mikhail O. Eremin

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Present work is devoted to experimental study and numerical modelling of failure of rocks typical for Kuzbass coal basin (Russia). The main goal was to define strength and deformation characteristics of rocks on the base of uniaxial compression and three-point bending loadings and then to build a mathematical model of failure process for both types of loading. Depending on particular physical-mechanical characteristics typical rocks of Kuzbass coal basin (sandstones, siltstones, mudstones, etc. of different series – Kolchuginsk, Tarbagansk, Balohonsk) manifest brittle and quasi-brittle character of failure. The strength characteristics for both tension and compression are found. Other characteristics are also found from the experiment or taken from literature reviews. On the base of obtained characteristics and structure (obtained from microscopy) the mathematical and structural models are built and numerical modelling of failure under different types of loading is carried out. Effective characteristics obtained from modelling and character of failure correspond to experiment and thus, the mathematical model was verified. An Instron 1185 machine was used to carry out the experiments. Mathematical model includes fundamental conservation laws of solid mechanics – mass, impulse, energy. Each rock has a sufficiently anisotropic structure, however, each crystallite might be considered as isotropic and then a whole rock model has a quasi-isotropic structure. This idea gives an opportunity to use the Hooke’s law inside of each crystallite and thus explicitly accounting for the anisotropy of rocks and the stress-strain state at loading. Inelastic behavior is described in frameworks of two different models: von Mises yield criterion and modified Drucker-Prager yield criterion. The damage accumulation theory is also implemented in order to describe a failure process. Obtained effective characteristics of rocks are used then for modelling of rock mass evolution when mining is carried out both by an open-pit or underground opening.

Keywords: damage accumulation, Drucker-Prager yield criterion, failure, mathematical modelling, three-point bending, uniaxial compression

Procedia PDF Downloads 172
184 In the Valley of the Shadow of Death: Gossip, God, and Scapegoating in Susannah, an American Opera by Carlisle Floyd

Authors: Shirl H. Terrell

Abstract:

In the telling of mythologies, stories of cultural and religious histories, the creative arts provide an archetypal lens through which the personal and collective unconscious are viewed, thus revealing mysteries of the unknown psyche. To that end, the author of this paper, using the hermeneutic approach, proves that Carlisle Floyd’s (1955) English language opera Susannah illuminates humanity’s instinctual nature and behaviors through music, libretto, and drama. While impressive musical works such as Wagner’s Ring Cycle and Webber’s Phantom of the Opera have received extensive Jungian analyses, critics and scholars often ignore lesser esteemed works, such as Susannah, notwithstanding the fact that they have been consistently performed on the theater circuit. Such pieces, when given notice, allow viewers to grasp the soul-making depth and timeless quality of productions which may otherwise go unrecognized as culturally or psychologically significant. Although Susannah has sometimes been described as unsophisticated and simple in scope, the author demonstrates why Floyd’s 'little' opera, set in New Hope Valley, Appalachia, a cultural region in the Eastern United States known for its prevailing myths and distortions of isolation, temperament, and the judgmentally conservative behavior of its inhabitants, belongs to opera’s hallmark works. Its approach to powerful underlying archetypal themes, which give rise to the poignant and haunting depictions of the darker and destructive side of the human soul, the Shadow, provides crucial significance to the work. The Shadow’s manifestation in the form of the scapegoating complex is central to the plot of Susannah; the church’s meting out of rules, judgment, and reparation for sins point to the foreboding aspects of human behavior that evoke their intrinsic nature. The scapegoating complex is highlighted in an eight-step process gleaned from the works of Kenneth Burke and Rene Girard. In summary, through depth psychological terms and mythological motifs, the author provides an insightful approach to perceiving instinctual behaviors as they play out in an American opera that has been staged over eight-hundred times, yet, unfortunately, remains in the shadows. Susannah’s timelessness is now.

Keywords: archetypes, mythology, opera, scapegoating, Shadow, Susannah

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