Search results for: OOC (orthogonal optical code)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3326

Search results for: OOC (orthogonal optical code)

326 Analytical Study and Conservation Processes of Scribe Box from Old Kingdom

Authors: Mohamed Moustafa, Medhat Abdallah, Ramy Magdy, Ahmed Abdrabou, Mohamed Badr

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The scribe box under study dates back to the old kingdom. It was excavated by the Italian expedition in Qena (1935-1937). The box consists of 2pieces, the lid and the body. The inner side of the lid is decorated with ancient Egyptian inscriptions written with a black pigment. The box was made using several panels assembled together by wooden dowels and secured with plant ropes. The entire box is covered with a red pigment. This study aims to use analytical techniques in order to identify and have deep understanding for the box components. Moreover, the authors were significantly interested in using infrared reflectance transmission imaging (RTI-IR) to improve the hidden inscriptions on the lid. The identification of wood species included in this study. The visual observation and assessment were done to understand the condition of this box. 3Ddimensions and 2D programs were used to illustrate wood joints techniques. Optical microscopy (OM), X-ray diffraction (XRD), X-ray fluorescence portable (XRF) and Fourier Transform Infrared spectroscopy (FTIR) were used in this study in order to identify wood species, remains of insects bodies, red pigment, fibers plant and previous conservation adhesives, also RTI-IR technique was very effective to improve hidden inscriptions. The analysis results proved that wooden panels and dowels were identified as Acacia nilotica, wooden rail was Salix sp. the insects were identified as Lasioderma serricorne and Gibbium psylloids, the red pigment was Hematite, while the fiber plants were linen, previous adhesive was identified as cellulose nitrates. The historical study for the inscriptions proved that it’s a Hieratic writings of a funerary Text. After its transportation from the Egyptian museum storage to the wood conservation laboratory of the Grand Egyptian museum –conservation center (GEM-CC), conservation techniques were applied with high accuracy in order to restore the object including cleaning , consolidating of friable pigments and writings, removal of previous adhesive and reassembly, finally the conservation process that were applied were extremely effective for this box which became ready for display or storage in the grand Egyptian museum.

Keywords: scribe box, hieratic, 3D program, Acacia nilotica, XRD, cellulose nitrate, conservation

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325 Seroepidemiological Study of Toxoplasma gondii Infection in Women of Child-Bearing Age in Communities in Osun State, Nigeria

Authors: Olarinde Olaniran, Oluyomi A. Sowemimo

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Toxoplasmosis is frequently misdiagnosed or underdiagnosed, and it is the third most common cause of hospitalization due to food-borne infection. Intra-uterine infection with Toxoplasma gondii due to active parasitaemia during pregnancy can cause severe and often fatal cerebral damage, abortion, and stillbirth of a fetus. The aim of the study was to investigate the prevalence of T. gondii infection in women of childbearing age in selected communities of Osun State with a view to determining the risk factors which predispose to the T. gondii infection. Five (5) ml of blood was collected by venopuncture into a plain blood collection tube by a medical laboratory scientist. Serum samples were separated by centrifuging the blood samples at 3000 rpm for 5 mins. The sera were collected with Eppendorf tubes and stored at -20°C analysis for the presence of IgG and IgM antibodies against T. gondii by commercially available enzyme-linked immunosorbent assay (ELISA) kit (Demeditec Diagnostics GmbH, Germany) conducted according to the manufacturer’s instructions. The optical densities of wells were measured by a photometer at a wavelength of 450 nm. Data collected were analysed using appropriate computer software. The overall seroprevalence of T. gondii among the women of child-bearing age in selected seven communities in Osun state was 76.3%. Out of 76.3% positive for Toxoplasma gondii infection, 70.0% were positive for anti- T. gondii IgG, and 32.3% were positive for IgM, and 26.7% for both IgG and IgM. The prevalence of T. gondii was lowest (58.9%) among women from Ile Ife, a peri-urban community, and highest (100%) in women residing in Alajue, a rural community. The prevalence of infection was significantly higher (P= 0.000) among Islamic women (87.5%) than in Christian women (70.8%). The highest prevalence (86.3%) was recorded in women with primary education, while the lowest (61.2%) was recorded in women with tertiary education (p =0.016). The highest prevalence (79.7%) was recorded in women that reside in rural areas, and the lowest (70.1%) was recorded in women that reside in peri-urban area (p=0.025). The prevalence of T. gondii infection was highest (81.4%) in women with one miscarriage, while the prevalence was lowest in women with no miscarriages (75.9%). The age of the women (p=0.042), Islamic religion (p=0.001), the residence of the women (p=0.001), and water source were all positively associated with T. gondii infection. The study concluded that there was a high seroprevalence of T. gondii recorded among women of child-bearing age in the study area. Hence, there is a need for health education and create awareness of the disease and its transmission to women of reproductive age group in general and pregnant women in particular to reduce the risk of T. gondii in pregnant women.

Keywords: seroepidemiology, Toxoplasma gondii, women, child-bearing, age, communities, Ile -Ife, Nigeria

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324 A Stepwise Approach for Piezoresistive Microcantilever Biosensor Optimization

Authors: Amal E. Ahmed, Levent Trabzon

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Due to the low concentration of the analytes in biological samples, the use of Biological Microelectromechanical System (Bio-MEMS) biosensors for biomolecules detection results in a minuscule output signal that is not good enough for practical applications. In response to this, a need has arisen for an optimized biosensor capable of giving high output signal in response the detection of few analytes in the sample; the ultimate goal is being able to convert the attachment of a single biomolecule into a measurable quantity. For this purpose, MEMS microcantilevers based biosensors emerged as a promising sensing solution because it is simple, cheap, very sensitive and more importantly does not need analytes optical labeling (Label-free). Among the different microcantilever transducing techniques, piezoresistive based microcantilever biosensors became more prominent because it works well in liquid environments and has an integrated readout system. However, the design of piezoresistive microcantilevers is not a straightforward problem due to coupling between the design parameters, constraints, process conditions, and performance. It was found that the parameters that can be optimized to enhance the sensitivity of Piezoresistive microcantilever-based sensors are: cantilever dimensions, cantilever material, cantilever shape, piezoresistor material, piezoresistor doping level, piezoresistor dimensions, piezoresistor position, Stress Concentration Region's (SCR) shape and position. After a systematic analyzation of the effect of each design and process parameters on the sensitivity, a step-wise optimization approach was developed in which almost all these parameters were variated one at each step while fixing the others to get the maximum possible sensitivity at the end. At each step, the goal was to optimize the parameter in a way that it maximizes and concentrates the stress in the piezoresistor region for the same applied force thus get the higher sensitivity. Using this approach, an optimized sensor that has 73.5x times higher electrical sensitivity (ΔR⁄R) than the starting sensor was obtained. In addition to that, this piezoresistive microcantilever biosensor it is more sensitive than the other similar sensors previously reported in the open literature. The mechanical sensitivity of the final senior is -1.5×10-8 Ω/Ω ⁄pN; which means that for each 1pN (10-10 g) biomolecules attach to this biosensor; the piezoresistor resistivity will decrease by 1.5×10-8 Ω. Throughout this work COMSOL Multiphysics 5.0, a commercial Finite Element Analysis (FEA) tool, has been used to simulate the sensor performance.

Keywords: biosensor, microcantilever, piezoresistive, stress concentration region (SCR)

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323 Unlocking Health Insights: Studying Data for Better Care

Authors: Valentina Marutyan

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Healthcare data mining is a rapidly developing field at the intersection of technology and medicine that has the potential to change our understanding and approach to providing healthcare. Healthcare and data mining is the process of examining huge amounts of data to extract useful information that can be applied in order to improve patient care, treatment effectiveness, and overall healthcare delivery. This field looks for patterns, trends, and correlations in a variety of healthcare datasets, such as electronic health records (EHRs), medical imaging, patient demographics, and treatment histories. To accomplish this, it uses advanced analytical approaches. Predictive analysis using historical patient data is a major area of interest in healthcare data mining. This enables doctors to get involved early to prevent problems or improve results for patients. It also assists in early disease detection and customized treatment planning for every person. Doctors can customize a patient's care by looking at their medical history, genetic profile, current and previous therapies. In this way, treatments can be more effective and have fewer negative consequences. Moreover, helping patients, it improves the efficiency of hospitals. It helps them determine the number of beds or doctors they require in regard to the number of patients they expect. In this project are used models like logistic regression, random forests, and neural networks for predicting diseases and analyzing medical images. Patients were helped by algorithms such as k-means, and connections between treatments and patient responses were identified by association rule mining. Time series techniques helped in resource management by predicting patient admissions. These methods improved healthcare decision-making and personalized treatment. Also, healthcare data mining must deal with difficulties such as bad data quality, privacy challenges, managing large and complicated datasets, ensuring the reliability of models, managing biases, limited data sharing, and regulatory compliance. Finally, secret code of data mining in healthcare helps medical professionals and hospitals make better decisions, treat patients more efficiently, and work more efficiently. It ultimately comes down to using data to improve treatment, make better choices, and simplify hospital operations for all patients.

Keywords: data mining, healthcare, big data, large amounts of data

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322 A Bottom-Up Approach for the Synthesis of Highly Ordered Fullerene-Intercalated Graphene Hybrids

Authors: A. Kouloumpis, P. Zygouri, G. Potsi, K. Spyrou, D. Gournis

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Much of the research effort on graphene focuses on its use as building block for the development of new hybrid nanostructures with well-defined dimensions and behavior suitable for applications among else in gas storage, heterogeneous catalysis, gas/liquid separations, nanosensing and biology. Towards this aim, here we describe a new bottom-up approach, which combines the self-assembly with the Langmuir Schaefer technique, for the production of fullerene-intercalated graphene hybrid materials. This new method uses graphene nanosheets as a template for the grafting of various fullerene C60 molecules (pure C60, bromo-fullerenes, C60Br24, and fullerols, C60(OH)24) in a bi-dimensional array, and allows for perfect layer-by-layer growth with control at the molecular level. Our film preparation approach involves a bottom-up layer-by-layer process that includes the formation of a hybrid organo-graphene Langmuir film hosting fullerene molecules within its interlayer spacing. A dilute water solution of chemically oxidized graphene (GO) was used as subphase on the Langmuir-Blodgett deposition system while an appropriate amino surfactant (that binds covalently with the GO) was applied for the formation of hybridized organo-GO. After the horizontal lift of a hydrophobic substrate, a surface modification of the GO platelets was performed by bringing the surface of the transferred Langmuir film in contact with a second amino surfactant solution (capable to interact strongly with the fullerene derivatives). In the final step, the hybrid organo-graphene film was lowered in the solution of the appropriate fullerene derivative. Multilayer films were constructed by repeating this procedure. Hybrid fullerene-based thin films deposited on various hydrophobic substrates were characterized by X-ray diffraction (XRD) and X-ray reflectivity (XRR), FTIR, and Raman spectroscopies, Atomic Force Microscopy, and optical measurements. Acknowledgments. This research has been co‐financed by the European Union (European Social Fund – ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF)‐Research Funding Program: THALES. Investing in knowledge society through the European Social Fund (no. 377285).

Keywords: hybrids, graphene oxide, fullerenes, langmuir-blodgett, intercalated structures

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321 Albinism in the South African Workplace: Reasonable Accommodation of a Black Person Living in a White Skin

Authors: Laetitia Fourie

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Dangerous myths and stereotypes contribute to the fact that persons living with albinism are amongst the most vulnerable groups in society. The prevalence of albinism varies around the world and the World Health Organization estimates that around 1 in 5000 people in Sub-Saharan Africa are affected by this genetic disorder. Persons who are living with the condition usually experience a lack of melanin in their skin, eyes and hair that results in possible physical impairments such as poor eyesight and skin cancers. Being affected by such disorders and consequently classified as an albino, give way for unequal treatment which ultimately requires safeguarding these persons against unfair discrimination - not only on the basis of their race and color (or lack thereof), but also on the basis of their disability. The Constitution of the Republic of South Africa provides that everyone is equal before the law and prohibits unfair discrimination on the grounds of race, color and disability. This right is given effect to by the Employment Equity Act, which strives to eliminate unfair discrimination on similar grounds within any employment policy or practice. An essential non-discrimination measure that can be implemented in the labor market to achieve equality is the duty of reasonable accommodation that rests upon employers. However, reasonable accommodation is only introduced as an affirmative action measure in order to provide equal employment opportunities to the identified designated groups who include black people (defined to include Indians, Chinese and Colored), women and people with disabilities. Even though this duty exists, South African law does not elaborate on the scope of the duty, except for a Disability Code, which does not hold the force of law. Furthermore, in respect of applying affirmative action measures to people with disabilities, the law does not elaborate on the meaning of disability. Considering that persons living with albinism will find it difficult to show that they are black or disabled in order to be acknowledged as part of the designated groups, their access to reasonable accommodation will be limited to a great extent. This paper will aim to illustrate to which extent South African law currently fails to implement its international obligations as a State Party to the Conventions of the United Nations, and how these failures should be corrected in order to serve the needs of all South Africans, including albinos.

Keywords: albinism, disability, equality, South Africa, United Nations

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320 Reading against the Grain: Transcodifying Stimulus Meaning

Authors: Aba-Carina Pârlog

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On translating, reading against the grain results in a wrong effect in the TL. Quine’s ocular irradiation plays an important part in the process of understanding and translating a text. The various types of textual radiation must be rendered by the translator by paying close attention to the types of field that produce it. The literary work must be seen as an indirect cause of an expressive effect in the TL that is supposed to be similar to the effect it has in the SL. If the adaptive transformative codes are so flexible that they encourage the translator to repeatedly leave out parts of the original work, then a subversive pattern emerges which changes the entire book. In this case, the translator is a writer per se who decides what goes in and out of the book, how the style is to be ciphered and what elements of ideology are to be highlighted. Figurative language must not be flattened for the sake of clarity or naturalness. The missing figurative elements make the translated text less interesting, less challenging and less vivid which reflects poorly on the writer. There is a close connection between style and the writer’s person. If the writer’s style is very much changed in a translation, the translation is useless as the original writer and his / her imaginative world can no longer be discovered. Then, a different writer appears and his / her creation surfaces. Changing meaning considered as a “negative shift” in translation defines one of the faulty transformative codes used by some translators. It is a dangerous tool which leads to adaptations that sometimes reflect the original less than the reader would wish to. It contradicts the very essence of the process of translation which is that of making a work available in a foreign language. Employing speculative aesthetics at the level of a text indicates the wish to create manipulative or subversive effects in the translated work. This is generally achieved by adding new words or connotations, creating new figures of speech or using explicitations. The irradiation patterns of the original work are neglected and the translator creates new meanings, implications, emphases and contexts. Again s/he turns into a new author who enjoys the freedom of expressing his / her ideas without the constraints of the original text. The stimulus meaning of a text is very important for a translator which is why reading against the grain is unadvisable during the process of translation. By paying attention to the waves of the SL input, a faithful literary work is produced which does not contradict general knowledge about foreign cultures and civilizations. Following personal common sense is essential in the field of translation as well as everywhere else.

Keywords: stimulus meaning, substance of expression, transformative code, translation

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319 Assessing the Feasibility of Italian Hydrogen Targets with the Open-Source Energy System Optimization Model TEMOA - Italy

Authors: Alessandro Balbo, Gianvito Colucci, Matteo Nicoli, Laura Savoldi

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Hydrogen is expected to become a game changer in the energy transition, especially enabling sector coupling possibilities and the decarbonization of hard-to-abate end-uses. The Italian National Recovery and Resilience Plan identifies hydrogen as one of the key elements of the ecologic transition to meet international decarbonization objectives, also including it in several pilot projects for the early development in Italy. This matches the European energy strategy, which aims to make hydrogen a leading energy carrier of the future, setting ambitious goals to be accomplished by 2030. The huge efforts needed to achieve the announced targets require to carefully investigate of their feasibility in terms of economic expenditures and technical aspects. In order to quantitatively assess the hydrogen potential within the Italian context and the feasibility of the planned investments and projects, this work uses the TEMOA-Italy energy system model to study pathways to meet the strict objectives above cited. The possible hydrogen development has been studied both in the supply-side and demand-side of the energy system, also including storage options and distribution chains. The assessment comprehends alternative hydrogen production technologies involved in a competition market, reflecting the several possible investments declined by the Italian National Recovery and Resilience Plan to boost the development and spread of this infrastructure, including the sector coupling potential with natural gas through the currently existing infrastructure and CO2 capture for the production of synfuels. On the other hand, the hydrogen end-uses phase covers a wide range of consumption alternatives, from fuel-cell vehicles, for which both road and non-road transport categories are considered, to steel, and chemical industries uses and cogeneration for residential and commercial buildings. The model includes both high and low TRL technologies in order to provide a consistent outcome for the future decades as it does for the present day, and since it is developed through the use of an open-source code instance and database, transparency and accessibility are fully granted.

Keywords: decarbonization, energy system optimization models, hydrogen, open-source modeling, TEMOA

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318 Artificial Neural Networks Application on Nusselt Number and Pressure Drop Prediction in Triangular Corrugated Plate Heat Exchanger

Authors: Hany Elsaid Fawaz Abdallah

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This study presents a new artificial neural network(ANN) model to predict the Nusselt Number and pressure drop for the turbulent flow in a triangular corrugated plate heat exchanger for forced air and turbulent water flow. An experimental investigation was performed to create a new dataset for the Nusselt Number and pressure drop values in the following range of dimensionless parameters: The plate corrugation angles (from 0° to 60°), the Reynolds number (from 10000 to 40000), pitch to height ratio (from 1 to 4), and Prandtl number (from 0.7 to 200). Based on the ANN performance graph, the three-layer structure with {12-8-6} hidden neurons has been chosen. The training procedure includes back-propagation with the biases and weight adjustment, the evaluation of the loss function for the training and validation dataset and feed-forward propagation of the input parameters. The linear function was used at the output layer as the activation function, while for the hidden layers, the rectified linear unit activation function was utilized. In order to accelerate the ANN training, the loss function minimization may be achieved by the adaptive moment estimation algorithm (ADAM). The ‘‘MinMax’’ normalization approach was utilized to avoid the increase in the training time due to drastic differences in the loss function gradients with respect to the values of weights. Since the test dataset is not being used for the ANN training, a cross-validation technique is applied to the ANN network using the new data. Such procedure was repeated until loss function convergence was achieved or for 4000 epochs with a batch size of 200 points. The program code was written in Python 3.0 using open-source ANN libraries such as Scikit learn, TensorFlow and Keras libraries. The mean average percent error values of 9.4% for the Nusselt number and 8.2% for pressure drop for the ANN model have been achieved. Therefore, higher accuracy compared to the generalized correlations was achieved. The performance validation of the obtained model was based on a comparison of predicted data with the experimental results yielding excellent accuracy.

Keywords: artificial neural networks, corrugated channel, heat transfer enhancement, Nusselt number, pressure drop, generalized correlations

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317 Green-Synthesized β-Cyclodextrin Membranes for Humidity Sensors

Authors: Zeineb Baatout, Safa Teka, Nejmeddine Jaballah, Nawfel Sakly, Xiaonan Sun, Mustapha Majdoub

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Currently, the economic interests linked to the development of bio-based materials make biomass one of the most interesting areas for science development. We are interested in the β-cyclodextrin (β-CD), one of the popular bio-sourced macromolecule, produced from the starch via enzymatic conversion. It is a cyclic oligosaccharide formed by the association of seven glucose units. It presents a rigid conical and amphiphilic structure with hydrophilic exterior, allowing it to be water-soluble. It has also a hydrophobic interior enabling the formation of inclusion complexes, which support its application for the elaboration of electrochemical and optical sensors. Nevertheless, the solubility of β-CD in water makes its use as sensitive layer limit and difficult due to their instability in aqueous media. To overcome this limitation, we chose to precede by modification of the hydroxyl groups to obtain hydrophobic derivatives which lead to water-stable sensing layers. Hence, a series of benzylated β-CDs were synthesized in basic aqueous media in one pot. This work reports the synthesis of a new family of substituted amphiphilic β-CDs using a green methodology. The obtained β-CDs showed different degree of substitution (DS) between 0.85 and 2.03. These organic macromolecular materials were soluble in common organic volatile solvents, and their structures were investigated by NMR, FT-IR and MALDI-TOF spectroscopies. Thermal analysis showed a correlation between the thermal properties of these derivatives and the benzylation degree. The surface properties of the thin films based on the benzylated β-CDs were characterized by contact angle measurements and atomic force microscopy (AFM). These organic materials were investigated as sensitive layers, deposited on quartz crystal microbalance (QCM) gravimetric transducer, for humidity sensor at room temperature. The results showed that the performances of the prepared sensors are greatly influenced by the benzylation degree of β-CD. The partially modified β-CD (DS=1) shows linear response with best sensitivity, good reproducibility, low hysteresis, fast response time (15s) and recovery time (17s) at higher relative humidity levels (RH) between 11% and 98% in room temperature.

Keywords: β-cyclodextrin, green synthesis, humidity sensor, quartz crystal microbalance

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316 Reverse Engineering of a Secondary Structure of a Helicopter: A Study Case

Authors: Jose Daniel Giraldo Arias, Camilo Rojas Gomez, David Villegas Delgado, Gullermo Idarraga Alarcon, Juan Meza Meza

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The reverse engineering processes are widely used in the industry with the main goal to determine the materials and the manufacture used to produce a component. There are a lot of characterization techniques and computational tools that are used in order to get this information. A study case of a reverse engineering applied to a secondary sandwich- hybrid type structure used in a helicopter is presented. The methodology used consists of five main steps, which can be applied to any other similar component: Collect information about the service conditions of the part, disassembly and dimensional characterization, functional characterization, material properties characterization and manufacturing processes characterization, allowing to obtain all the supports of the traceability of the materials and processes of the aeronautical products that ensure their airworthiness. A detailed explanation of each step is covered. Criticality and comprehend the functionalities of each part, information of the state of the art and information obtained from interviews with the technical groups of the helicopter’s operators were analyzed,3D optical scanning technique, standard and advanced materials characterization techniques and finite element simulation allow to obtain all the characteristics of the materials used in the manufacture of the component. It was found that most of the materials are quite common in the aeronautical industry, including Kevlar, carbon, and glass fibers, aluminum honeycomb core, epoxy resin and epoxy adhesive. The stacking sequence and volumetric fiber fraction are a critical issue for the mechanical behavior; a digestion acid method was used for this purpose. This also helps in the determination of the manufacture technique which for this case was Vacuum Bagging. Samples of the material were manufactured and submitted to mechanical and environmental tests. These results were compared with those obtained during reverse engineering, which allows concluding that the materials and manufacture were correctly determined. Tooling for the manufacture was designed and manufactured according to the geometry and manufacture process requisites. The part was manufactured and the mechanical, and environmental tests required were also performed. Finally, a geometric characterization and non-destructive techniques allow verifying the quality of the part.

Keywords: reverse engineering, sandwich-structured composite parts, helicopter, mechanical properties, prototype

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315 Moderating Effect of Different Social Supports on the Relationship between Workplace Bullying and Intention to Occupation Leave in Nurses

Authors: Chenchieh Chang

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Objectives: This study had two objectives. First, it used affective events theory to investigate the relationship between workplace bullying and the intention to resign in nurses, a topic rarely explored in previous studies. Second, according to the conservation of resource theory, individuals encountering work incidents will utilize resources that are at their disposal to strengthen or weaken the effects of the incidents on them. Such resources include social support that comes from their bosses, colleagues, family, and friends. To answer the question of whether different social supports exert distinct effects on alleviating stress experienced by nurses, this study examined the moderating effects of different social supports on the relationship between workplace bullying and nurses’ intention to resign. Method: This study was approved by an institutional review board (code number: 105070) and adopted purposive sampling to survey 911, full-time nurses. Results: Work-related bullying exerted a significant and positive effect on the intention to resign, whereas bullying pertaining to interpersonal relationships and body-related bullying nonsignificantly affected intention to resign. Support from supervisors enhanced the effect of work-related bullying on an intention to resign, whereas support from colleagues and family did not moderate said effect. Research Limitations/Implications: The self-reporting method and cross-sectional research design adopted in this study might have resulted in common method variance and limited the ability to make causal inferences. This study suggests future studies to obtain measures of predictor and criterion variables from different sources or ensure a temporal, proximal, or psychological separation between predictor and criterion in the collection of data to avoid the common method bias. Practical Implications: First, businesses should establish a friendly work environment and prevent employees from encountering workplace bullying. Second, because social support cannot diminish the effect of workplace bullying on employees’ intention to resign, businesses should offer other means of assistance. For example, business managers may introduce confidential systems for employees to report workplace bullying; or they may establish consultation centers where employees can properly express their thoughts and feelings when encountering workplace bullying.

Keywords: workplace bullying, intention to occupation leave, social supports, nurses

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314 The Role of Nurses and Midwives’ Self-Government in Postgraduate Education in Poland

Authors: Tomasz Holecki, Hanna Dobrowolska

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In the Polish health care system, nurses and midwives are obliged to regularly update their professional knowledge. It is all regulated by the Law on the nurse and midwife’s profession and the code of ethics. The professional self-governing body (County Chamber of Nurses and Midwives) is obliged to organize ongoing training for them so that maintaining accessibility and availability to the high quality of educational services could be possible at all levels of post-graduate education. The aim of this study is an analysis of post-graduate education organized by the County Chamber of Nurses and Midwives in the city of Katowice, Poland, as a professional self-governing body operating in the area of Silesian province inhabited by almost 5 million citizens which bring together more than 30 thousand professionally active nurses and midwives. In the years 2000-2017, the self-government of nurses and midwives trained over 50,000 people. The education and supervision system over the labour of nurses and midwives establishes exercising control by a self-governing body. In practice, this means that conducting activities aimed at creating legal regulations and organizational conditions, as well as the practical implementation of courses, belongs to the professional self-government of nurses and midwives. The most of specialization courses that were provided from their own funds came from membership fees. The biggest group was participants of specializations in the fields of cardiac, anesthesia, and preventive nursing. The smallest group of people participated in such specializations as neonatal, emergency, and obstetrics nursing. The most popular specialist courses were in the fields of the electrocardiogram and cardiopulmonary resuscitation, whereas the least popular were the ones in the fields of protective vaccinations of neonates. So-called 'soft training-courses' in the fields of improvement of social skills and management were also provided. The research shows that a vast majority of nurses and midwives are interested in raising their professional qualifications. Specialist courses and selected fields of qualification courses received the most concrete attention. In light of conducted research, one can assert that cooperation inside the community of nurses and midwives provides access to high-quality education and training services regularly used by a wide circle of them. The presented results exemplify a level of real interest in specialist and qualification training-courses and also show sources of financing them.

Keywords: nurses and midwives, ongoing training, postgraduate education, specialist training-courses

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313 At the Intersection of Race and Gender in Social Work Education

Authors: LaShawnda N. Fields, Valandra

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There remains much to learn about the experiences of Black women within social work education. Higher education, in general, has a strained relationship with this demographic and while social work has espoused a code of ethics and core values, Black women report inequitable experiences similar to those in other disciplines. Research-intensive (R-1) Carnegie-designated institutions typically have lower representation of those with historically marginalized identities; this study focuses on Black women in these schools of social work. This study presents qualitative findings from 9 in-depth interviews with Black women faculty members as well as interviews with 11 Black women doctoral students at R-1 universities. Many of the poor professional outcomes for Black women in academia are a result of their experiences with imposter syndrome and feeling as though they cannot present their authentic selves. The finding of this study highlighted the many ways imposter syndrome manifests within these study participants, from an inability to be productive to overproducing in an effort to win the respect and support of colleagues. Being scrutinized and seen as unprofessional when being authentic has led to some Black women isolating themselves and struggling to remain in academia. Other Black women have decided that regardless of the backlash they may receive, they will proudly present their authentic selves and allow their work to speak for itself rather than conform to the dominant White culture. These semi-structured, in-depth interviews shined a spotlight on the ways Black women doctoral students were denied inclusion throughout their programs. These students often believed both faculty members and peers seemed to actively work to ensure discomfort in these women. In response to these negative experiences and a lack of support, many of these Black women doctoral students created their own networks of support. These networks of support often included faculty members within social work but also beyond their discipline and outside of the academy at large. The faculty members who offered support to this demographic typically shared their race and gender identities. Both Black women faculty members and doctoral students historically have been forced to prioritize surviving, not thriving as a result of toxic environments within their schools of social work. This has negatively impacted their mental health and their levels of productivity. It is necessary for these institutions to build trust with these women by respecting their diverse backgrounds, supporting their race-related research interests, and honoring the rigor in a range of methodologies if substantial, sustainable change is to be achieved.

Keywords: education, equity, inclusion, intersectionality

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312 Fabrication of Carbon Nanoparticles and Graphene Using Pulsed Laser Ablation

Authors: Davoud Dorranian, Hajar Sadeghi, Elmira Solati

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Carbon nanostructures in various forms were synthesized using pulsed laser ablation of a graphite target in different liquid environment. The beam of a Q-switched Nd:YAG laser of 1064-nm wavelength at 7-ns pulse width is employed to irradiate the solid target in water, acetone, alcohol, and cetyltrimethylammonium bromide (CTAB). Then the effect of the liquid environment on the characteristic of carbon nanostructures produced by laser ablation was investigated. The optical properties of the carbon nanostructures were examined at room temperature by UV–Vis-NIR spectrophotometer. The crystalline structure of the carbon nanostructures was analyzed by X-ray diffraction (XRD). The morphology of samples was investigated by field emission scanning electron microscope (FE-SEM). Transmission electron microscope (TEM) was employed to investigate the form of carbon nanostructures. Raman spectroscopy was used to determine the quality of carbon nanostructures. Results show that different carbon nanostructures such as nanoparticles and few-layer graphene were formed in various liquid environments. The UV-Vis-NIR absorption spectra of samples reveal that the intensity of absorption peak of nanoparticles in alcohol is higher than the other liquid environments due to the larger number of nanoparticles in this environment. The red shift of the absorption peak of the sample in acetone confirms that produced carbon nanoparticles in this liquid are averagely larger than the other medium. The difference in the intensity and shape of the absorption peak indicated the effect of the liquid environment in producing the nanoparticles. The XRD pattern of the sample in water indicates an amorphous structure due to existence the graphene sheets. X-ray diffraction pattern shows that the degree of crystallinity of sample produced in CTAB is higher than the other liquid environments. Transmission electron microscopy images reveal that the generated carbon materials in water are graphene sheet and in the other liquid environments are graphene sheet and spherical nanostructures. According to the TEM images, we have the larger amount of carbon nanoparticles in the alcohol environment. FE-SEM micrographs indicate that in this liquids sheet like structures are formed however in acetone, produced sheets are adhered and these layers overlap with each other. According to the FE-SEM micrographs, the surface morphology of the sample in CTAB was coarser than that without surfactant. From Raman spectra, it can be concluded the distinct shape, width, and position of the graphene peaks and corresponding graphite source.

Keywords: carbon nanostructures, graphene, pulsed laser ablation, graphite

Procedia PDF Downloads 309
311 Resonant Fluorescence in a Two-Level Atom and the Terahertz Gap

Authors: Nikolai N. Bogolubov, Andrey V. Soldatov

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Terahertz radiation occupies a range of frequencies somewhere from 100 GHz to approximately 10 THz, just between microwaves and infrared waves. This range of frequencies holds promise for many useful applications in experimental applied physics and technology. At the same time, reliable, simple techniques for generation, amplification, and modulation of electromagnetic radiation in this range are far from been developed enough to meet the requirements of its practical usage, especially in comparison to the level of technological abilities already achieved for other domains of the electromagnetic spectrum. This situation of relative underdevelopment of this potentially very important range of electromagnetic spectrum is known under the name of the 'terahertz gap.' Among other things, technological progress in the terahertz area has been impeded by the lack of compact, low energy consumption, easily controlled and continuously radiating terahertz radiation sources. Therefore, development of new techniques serving this purpose as well as various devices based on them is of obvious necessity. No doubt, it would be highly advantageous to employ the simplest of suitable physical systems as major critical components in these techniques and devices. The purpose of the present research was to show by means of conventional methods of non-equilibrium statistical mechanics and the theory of open quantum systems, that a thoroughly studied two-level quantum system, also known as an one-electron two-level 'atom', being driven by external classical monochromatic high-frequency (e.g. laser) field, can radiate continuously at much lower (e.g. terahertz) frequency in the fluorescent regime if the transition dipole moment operator of this 'atom' possesses permanent non-equal diagonal matrix elements. This assumption contradicts conventional assumption routinely made in quantum optics that only the non-diagonal matrix elements persist. The conventional assumption is pertinent to natural atoms and molecules and stems from the property of spatial inversion symmetry of their eigenstates. At the same time, such an assumption is justified no more in regard to artificially manufactured quantum systems of reduced dimensionality, such as, for example, quantum dots, which are often nicknamed 'artificial atoms' due to striking similarity of their optical properties to those ones of the real atoms. Possible ways to experimental observation and practical implementation of the predicted effect are discussed too.

Keywords: terahertz gap, two-level atom, resonant fluorescence, quantum dot, resonant fluorescence, two-level atom

Procedia PDF Downloads 265
310 Using Photogrammetric Techniques to Map the Mars Surface

Authors: Ahmed Elaksher, Islam Omar

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For many years, Mars surface has been a mystery for scientists. Lately with the help of geospatial data and photogrammetric procedures researchers were able to capture some insights about this planet. Two of the most imperative data sources to explore Mars are the The High Resolution Imaging Science Experiment (HiRISE) and the Mars Orbiter Laser Altimeter (MOLA). HiRISE is one of six science instruments carried by the Mars Reconnaissance Orbiter, launched August 12, 2005, and managed by NASA. The MOLA sensor is a laser altimeter carried by the Mars Global Surveyor (MGS) and launched on November 7, 1996. In this project, we used MOLA-based DEMs to orthorectify HiRISE optical images for generating a more accurate and trustful surface of Mars. The MOLA data was interpolated using the kriging interpolation technique. Corresponding tie points were digitized from both datasets. These points were employed in co-registering both datasets using GIS analysis tools. In this project, we employed three different 3D to 2D transformation models. These are the parallel projection (3D affine) transformation model; the extended parallel projection transformation model; the Direct Linear Transformation (DLT) model. A set of tie-points was digitized from both datasets. These points were split into two sets: Ground Control Points (GCPs), used to evaluate the transformation parameters using least squares adjustment techniques, and check points (ChkPs) to evaluate the computed transformation parameters. Results were evaluated using the RMSEs between the precise horizontal coordinates of the digitized check points and those estimated through the transformation models using the computed transformation parameters. For each set of GCPs, three different configurations of GCPs and check points were tested, and average RMSEs are reported. It was found that for the 2D transformation models, average RMSEs were in the range of five meters. Increasing the number of GCPs from six to ten points improve the accuracy of the results with about two and half meters. Further increasing the number of GCPs didn’t improve the results significantly. Using the 3D to 2D transformation parameters provided three to two meters accuracy. Best results were reported using the DLT transformation model. However, increasing the number of GCPS didn’t have substantial effect. The results support the use of the DLT model as it provides the required accuracy for ASPRS large scale mapping standards. However, well distributed sets of GCPs is a key to provide such accuracy. The model is simple to apply and doesn’t need substantial computations.

Keywords: mars, photogrammetry, MOLA, HiRISE

Procedia PDF Downloads 55
309 CFD Simulation of Spacer Effect on Turbulent Mixing Phenomena in Sub Channels of Boiling Nuclear Assemblies

Authors: Shashi Kant Verma, S. L. Sinha, D. K. Chandraker

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Numerical simulations of selected subchannel tracer (Potassium Nitrate) based experiments have been performed to study the capabilities of state-of-the-art of Computational Fluid Dynamics (CFD) codes. The Computational Fluid Dynamics (CFD) methodology can be useful for investigating the spacer effect on turbulent mixing to predict turbulent flow behavior such as Dimensionless mixing scalar distributions, radial velocity and vortices in the nuclear fuel assembly. A Gibson and Launder (GL) Reynolds stress model (RSM) has been selected as the primary turbulence model to be applied for the simulation case as it has been previously found reasonably accurate to predict flows inside rod bundles. As a comparison, the case is also simulated using a standard k-ε turbulence model that is widely used in industry. Despite being an isotropic turbulence model, it has also been used in the modeling of flow in rod bundles and to produce lateral velocities after thorough mixing of coolant fairly. Both these models have been solved numerically to find out fully developed isothermal turbulent flow in a 30º segment of a 54-rod bundle. Numerical simulation has been carried out for the study of natural mixing of a Tracer (Passive scalar) to characterize the growth of turbulent diffusion in an injected sub-channel and, afterwards on, cross-mixing between adjacent sub-channels. The mixing with water has been numerically studied by means of steady state CFD simulations with the commercial code STAR-CCM+. Flow enters into the computational domain through the mass inflow at the three subchannel faces. Turbulence intensity and hydraulic diameter of 1% and 5.9 mm respectively were used for the inlet. A passive scalar (Potassium nitrate) is injected through the mass fraction of 5.536 PPM at subchannel 2 (Upstream of the mixing section). Flow exited the domain through the pressure outlet boundary (0 Pa), and the reference pressure was 1 atm. Simulation results have been extracted at different locations of the mixing zone and downstream zone. The local mass fraction shows uniform mixing. The effect of the applied turbulence model is nearly negligible just before the outlet plane because the distributions look like almost identical and the flow is fully developed. On the other hand, quantitatively the dimensionless mixing scalar distributions change noticeably, which is visible in the different scale of the colour bars.

Keywords: single-phase flow, turbulent mixing, tracer, sub channel analysis

Procedia PDF Downloads 203
308 What Are the Problems in the Case of Analysis of Selenium by Inductively Coupled Plasma Mass Spectrometry in Food and Food Raw Materials?

Authors: Béla Kovács, Éva Bódi, Farzaneh Garousi, Szilvia Várallyay, Dávid Andrási

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For analysis of elements in different food, feed and food raw material samples generally a flame atomic absorption spectrometer (FAAS), a graphite furnace atomic absorption spectrometer (GF-AAS), an inductively coupled plasma optical emission spectrometer (ICP-OES) and an inductively coupled plasma mass spectrometer (ICP-MS) are applied. All the analytical instruments have different physical and chemical interfering effects analysing food and food raw material samples. The smaller the concentration of an analyte and the larger the concentration of the matrix the larger the interfering effects. Nowadays, it is very important to analyse growingly smaller concentrations of elements. From the above analytical instruments generally the inductively coupled plasma mass spectrometer is capable of analysing the smallest concentration of elements. The applied ICP-MS instrument has Collision Cell Technology (CCT) also. Using CCT mode certain elements have better detection limits with 1-3 magnitudes comparing to a normal ICP-MS analytical method. The CCT mode has better detection limits mainly for analysis of selenium (arsenic, germanium, vanadium, and chromium). To elaborate an analytical method for selenium with an inductively coupled plasma mass spectrometer the most important interfering effects (problems) were evaluated: 1) isobaric elemental, 2) isobaric molecular, and 3) physical interferences. Analysing food and food raw material samples an other (new) interfering effect emerged in ICP-MS, namely the effect of various matrixes having different evaporation and nebulization effectiveness, moreover having different quantity of carbon content of food, feed and food raw material samples. In our research work the effect of different water-soluble compounds furthermore the effect of various quantity of carbon content (as sample matrix) were examined on changes of intensity of selenium. So finally we could find “opportunities” to decrease the error of selenium analysis. To analyse selenium in food, feed and food raw material samples, the most appropriate inductively coupled plasma mass spectrometer is a quadrupole instrument applying a collision cell technique (CCT). The extent of interfering effect of carbon content depends on the type of compounds. The carbon content significantly affects the measured concentration (intensities) of Se, which can be corrected using internal standard (arsenic or tellurium).

Keywords: selenium, ICP-MS, food, food raw material

Procedia PDF Downloads 503
307 Bandgap Engineering of CsMAPbI3-xBrx Quantum Dots for Intermediate Band Solar Cell

Authors: Deborah Eric, Abbas Ahmad Khan

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Lead halide perovskites quantum dots have attracted immense scientific and technological interest for successful photovoltaic applications because of their remarkable optoelectronic properties. In this paper, we have simulated CsMAPbI3-xBrx based quantum dots to implement their use in intermediate band solar cells (IBSC). These types of materials exhibit optical and electrical properties distinct from their bulk counterparts due to quantum confinement. The conceptual framework provides a route to analyze the electronic properties of quantum dots. This layer of quantum dots optimizes the position and bandwidth of IB that lies in the forbidden region of the conventional bandgap. A three-dimensional MAPbI3 quantum dot (QD) with geometries including spherical, cubic, and conical has been embedded in the CsPbBr3 matrix. Bound energy wavefunction gives rise to miniband, which results in the formation of IB. If there is more than one miniband, then there is a possibility of having more than one IB. The optimization of QD size results in more IBs in the forbidden region. One band time-independent Schrödinger equation using the effective mass approximation with step potential barrier is solved to compute the electronic states. Envelope function approximation with BenDaniel-Duke boundary condition is used in combination with the Schrödinger equation for the calculation of eigen energies and Eigen energies are solved for the quasi-bound states using an eigenvalue study. The transfer matrix method is used to study the quantum tunneling of MAPbI3 QD through neighbor barriers of CsPbI3. Electronic states are computed using Schrödinger equation with effective mass approximation by considering quantum dot and wetting layer assembly. Results have shown the varying the quantum dot size affects the energy pinning of QD. Changes in the ground, first, second state energies have been observed. The QD is non-zero at the center and decays exponentially to zero at boundaries. Quasi-bound states are characterized by envelope functions. It has been observed that conical quantum dots have maximum ground state energy at a small radius. Increasing the wetting layer thickness exhibits energy signatures similar to bulk material for each QD size.

Keywords: perovskite, intermediate bandgap, quantum dots, miniband formation

Procedia PDF Downloads 159
306 The Quantitative Optical Modulation of Dopamine Receptor-Mediated Endocytosis Using an Optogenetic System

Authors: Qiaoyue Kuang, Yang Li, Mizuki Endo, Takeaki Ozawa

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G protein-coupled receptors (GPCR) are the largest family of receptor proteins that detect molecules outside the cell and activate cellular responses. Of the GPCRs, dopamine receptors, which recognize extracellular dopamine, are essential to mammals due to their roles in numerous physiological events, including autonomic movement, hormonal regulation, emotions, and the reward system in the brain. To precisely understand the physiological roles of dopamine receptors, it is important to spatiotemporally control the signaling mediated by dopamine receptors, which is strongly dependent on their surface expression. Conventionally, chemical-induced interactions were applied to trigger the endocytosis of cell surface receptors. However, these methods were subjected to diffusion and therefore lacked temporal and special precision. To further understand the receptor-mediated signaling and to control the plasma membrane expression of receptors, an optogenetic tool called E-fragment was developed. The C-terminus of a light-sensitive photosensory protein cyptochrome2 (CRY2) was attached to β-Arrestin, and the E-fragment was generated by fusing the C-terminal peptide of vasopressin receptor (V2R) to CRY2’s binding partner protein CIB. The CRY2-CIB heterodimerization triggered by blue light stimulation brings β-Arrestin to the vicinity of membrane receptors and results in receptor endocytosis. In this study, the E-fragment system was applied to dopamine receptors 1 and 2 (DRD1 and DRD2) to control dopamine signaling. First, confocal fluorescence microscope observation qualitatively confirmed the light-induced endocytosis of E-fragment fused receptors. Second, NanoBiT bioluminescence assay verified quantitatively that the surface amount of E-fragment labeled receptors decreased after light treatment. Finally, GloSensor bioluminescence assay results suggested that the E-fragment-dependent receptor light-induced endocytosis decreased cAMP production in DRD1 signaling and attenuated the inhibition effect of DRD2 on cAMP production. The developed optogenetic tool was able to induce receptor endocytosis by external light, providing opportunities to further understand numerous physiological activities by controlling receptor-mediated signaling spatiotemporally.

Keywords: dopamine receptors, endocytosis, G protein-coupled receptors, optogenetics

Procedia PDF Downloads 91
305 Flood Mapping Using Height above the Nearest Drainage Model: A Case Study in Fredericton, NB, Canada

Authors: Morteza Esfandiari, Shabnam Jabari, Heather MacGrath, David Coleman

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Flood is a severe issue in different places in the world as well as the city of Fredericton, New Brunswick, Canada. The downtown area of Fredericton is close to the Saint John River, which is susceptible to flood around May every year. Recently, the frequency of flooding seems to be increased, especially after the fact that the downtown area and surrounding urban/agricultural lands got flooded in two consecutive years in 2018 and 2019. In order to have an explicit vision of flood span and damage to affected areas, it is necessary to use either flood inundation modelling or satellite data. Due to contingent availability and weather dependency of optical satellites, and limited existing data for the high cost of hydrodynamic models, it is not always feasible to rely on these sources of data to generate quality flood maps after or during the catastrophe. Height Above the Nearest Drainage (HAND), a state-of-the-art topo-hydrological index, normalizes the height of a basin based on the relative elevation along with the stream network and specifies the gravitational or the relative drainage potential of an area. HAND is a relative height difference between the stream network and each cell on a Digital Terrain Model (DTM). The stream layer is provided through a multi-step, time-consuming process which does not always result in an optimal representation of the river centerline depending on the topographic complexity of that region. HAND is used in numerous case studies with quite acceptable and sometimes unexpected results because of natural and human-made features on the surface of the earth. Some of these features might cause a disturbance in the generated model, and consequently, the model might not be able to predict the flow simulation accurately. We propose to include a previously existing stream layer generated by the province of New Brunswick and benefit from culvert maps to improve the water flow simulation and accordingly the accuracy of HAND model. By considering these parameters in our processing, we were able to increase the accuracy of the model from nearly 74% to almost 92%. The improved model can be used for generating highly accurate flood maps, which is necessary for future urban planning and flood damage estimation without any need for satellite imagery or hydrodynamic computations.

Keywords: HAND, DTM, rapid floodplain, simplified conceptual models

Procedia PDF Downloads 143
304 Study of Oxidative Processes in Blood Serum in Patients with Arterial Hypertension

Authors: Laura M. Hovsepyan, Gayane S. Ghazaryan, Hasmik V. Zanginyan

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Hypertension (HD) is the most common cardiovascular pathology that causes disability and mortality in the working population. Most often, heart failure (HF), which is based on myocardial remodeling, leads to death in hypertension. Recently, endothelial dysfunction (EDF) or a violation of the functional state of the vascular endothelium has been assigned a significant role in the structural changes in the myocardium and the occurrence of heart failure in patients with hypertension. It has now been established that tissues affected by inflammation form increased amounts of superoxide radical and NO, which play a significant role in the development and pathogenesis of various pathologies. They mediate inflammation, modify proteins and damage nucleic acids. The aim of this work was to study the processes of oxidative modification of proteins (OMP) and the production of nitric oxide in hypertension. In the experimental work, the blood of 30 donors and 33 patients with hypertension was used. For the quantitative determination of OMP products, the based on the reaction of the interaction of oxidized amino acid residues of proteins and 2,4-dinitrophenylhydrazine (DNPH) with the formation of 2,4-dinitrophenylhydrazones, the amount of which was determined spectrophotometrically. The optical density of the formed carbonyl derivatives of dinitrophenylhydrazones was recorded at different wavelengths: 356 nm - aliphatic ketone dinitrophenylhydrazones (KDNPH) of neutral character; 370 nm - aliphatic aldehyde dinirophenylhydrazones (ADNPH) of neutral character; 430 nm - aliphatic KDNFG of the main character; 530 nm - basic aliphatic ADNPH. Nitric oxide was determined by photometry using Grace's solution. Adsorption was measured on a Thermo Scientific Evolution 201 SF at a wavelength of 546 nm. Thus, the results of the studies showed that in patients with arterial hypertension, an increased level of nitric oxide in the blood serum is observed, and there is also a tendency to an increase in the intensity of oxidative modification of proteins at a wavelength of 270 nm and 363 nm, which indicates a statistically significant increase in aliphatic aldehyde and ketone dinitrophenylhydrazones. The increase in the intensity of oxidative modification of blood plasma proteins in the studied patients, revealed by us, actually reflects the general direction of free radical processes and, in particular, the oxidation of proteins throughout the body. A decrease in the activity of the antioxidant system also leads to a violation of protein metabolism. The most important consequence of the oxidative modification of proteins is the inactivation of enzymes.

Keywords: hypertension (HD), oxidative modification of proteins (OMP), nitric oxide (NO), oxidative stress

Procedia PDF Downloads 99
303 Analytical and Numerical Studies on the Behavior of a Freezing Soil Layer

Authors: X. Li, Y. Liu, H. Wong, B. Pardoen, A. Fabbri, F. McGregor, E. Liu

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The target of this paper is to investigate how saturated poroelastic soils subject to freezing temperatures behave and how different boundary conditions can intervene and affect the thermo-hydro-mechanical (THM) responses, based on a particular but classical configuration of a finite homogeneous soil layer studied by Terzaghi. The essential relations on the constitutive behavior of a freezing soil are firstly recalled: ice crystal - liquid water thermodynamic equilibrium, hydromechanical constitutive equations, momentum balance, water mass balance, and the thermal diffusion equation, in general, non-linear case where material parameters are state-dependent. The system of equations is firstly linearized, assuming all material parameters to be constants, particularly the permeability of liquid water, which should depend on the ice content. Two analytical solutions solved by the classic Laplace transform are then developed, accounting for two different sets of boundary conditions. Afterward, the general non-linear equations with state-dependent parameters are solved using a commercial code COMSOL based on finite elements method to obtain numerical results. The validity of this numerical modeling is partially verified using the analytical solution in the limiting case of state-independent parameters. Comparison between the results given by the linearized analytical solutions and the non-linear numerical model reveals that the above-mentioned linear computation will always underestimate the liquid pore pressure and displacement, whatever the hydraulic boundary conditions are. In the nonlinear model, the faster growth of ice crystals, accompanying the subsequent reduction of permeability of freezing soil layer, makes a longer duration for the depressurization of water liquid and slower settlement in the case where the ground surface is swiftly covered by a thin layer of ice, as well as a bigger global liquid pressure and swelling in the case of the impermeable ground surface. Nonetheless, the analytical solutions based on linearized equations give a correct order-of-magnitude estimate, especially at moderate temperature variations, and remain a useful tool for preliminary design checks.

Keywords: chemical potential, cryosuction, Laplace transform, multiphysics coupling, phase transformation, thermodynamic equilibrium

Procedia PDF Downloads 75
302 Spark Plasma Sintering/Synthesis of Alumina-Graphene Composites

Authors: Nikoloz Jalabadze, Roin Chedia, Lili Nadaraia, Levan Khundadze

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Nanocrystalline materials in powder condition can be manufactured by a number of different methods, however manufacture of composite materials product in the same nanocrystalline state is still a problem because the processes of compaction and synthesis of nanocrystalline powders go with intensive growth of particles – the process which promotes formation of pieces in an ordinary crystalline state instead of being crystallized in the desirable nanocrystalline state. To date spark plasma sintering (SPS) has been considered as the most promising and energy efficient method for producing dense bodies of composite materials. An advantage of the SPS method in comparison with other methods is mainly low temperature and short time of the sintering procedure. That finally gives an opportunity to obtain dense material with nanocrystalline structure. Graphene has recently garnered significant interest as a reinforcing phase in composite materials because of its excellent electrical, thermal and mechanical properties. Graphene nanoplatelets (GNPs) in particular have attracted much interest as reinforcements for ceramic matrix composites (mostly in Al2O3, Si3N4, TiO2, ZrB2 a. c.). SPS has been shown to fully densify a variety of ceramic systems effectively including Al2O3 and often with improvements in mechanical and functional behavior. Alumina consolidated by SPS has been shown to have superior hardness, fracture toughness, plasticity and optical translucency compared to conventionally processed alumina. Knowledge of how GNPs influence sintering behavior is important to effectively process and manufacture process. In this study, the effects of GNPs on the SPS processing of Al2O3 are investigated by systematically varying sintering temperature, holding time and pressure. Our experiments showed that SPS process is also appropriate for the synthesis of nanocrystalline powders of alumina-graphene composites. Depending on the size of the molds, it is possible to obtain different amount of nanopowders. Investigation of the structure, physical-chemical, mechanical and performance properties of the elaborated composite materials was performed. The results of this study provide a fundamental understanding of the effects of GNP on sintering behavior, thereby providing a foundation for future optimization of the processing of these promising nanocomposite systems.

Keywords: alumina oxide, ceramic matrix composites, graphene nanoplatelets, spark-plasma sintering

Procedia PDF Downloads 372
301 Risk of Mortality and Spectrum of Second Primary Malignancies in Mantle Cell Lymphoma before and after Ibrutinib Approval: A Population-Based Study

Authors: Karthik Chamari, Vasudha Rudraraju, Gaurav Chaudhari

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Background: Mantle cell lymphoma (MCL) is one of the mature B cell non-Hodgkin lymphomas (NHL). The course of MCL is moderately aggressive and variable, and it has median overall survival of 8 to 10 years. Ibrutinib, a Bruton’s tyrosine kinase inhibitor, was approved by the United States (US) Food and Drug Administration in November of 2013 for the treatment of MCL patients who have received at least one prior therapy. In this study, we aimed to evaluate whether there has been a change in survival and patterns of second primary malignancies (SPMs) among the MCL population in the US after ibrutinib approval. Methods: Using the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER)-18, we conducted a retrospective study with patients diagnosed with MCL (ICD-0-3 code 9673/3) between 2007 and 2018. We divided patients into two six-year cohorts, pre-ibrutinib approval (2007-2012) and post-ibrutinib approval (2013-2018), and compared relative survival rates (RSRs) and standardized incidence ratios (SIRs) of SPMs between cohorts. Results: We included 9,257 patients diagnosed with MCL between 2007 and 2018 in the SEER-18 survival and SIR registries. Of these, 4,205 (45%) patients were included in the pre-ibrutinib cohort, and 5052 (55%) patients were included in the post-ibrutinib cohort. The median follow-up duration for the pre-ibrutinib cohort was 54 months (range 0 to 143 months), and the post-ibrutinib cohort was 20 months (range 0 to 71 months). There was a significant difference in the five-year RSRs between pre-ibrutinib and post-ibrutinib cohorts (57.5% vs. 62.6%, p < 0.005). Out of the 9,257 patients diagnosed with MCL, 920 developed SPMs. A higher proportion of SPMs occurred in the post-ibrutinib cohort (63%) when compared with the pre-ibrutinib cohort (37%). Non-hematological malignancies comprised most of all SPMs. A higher incidence of non-hematological malignancies occurred in the post-ibrutinib cohort (SIR 1.42, 95% CI 1.29 to 1.56) when compared with the pre-ibrutinib cohort (SIR 1.14, 95% CI 1 to 1.3). There was a statistically significant increase in the incidence of cancers of the respiratory tract (SIR 1.77, 95% CI 1.43 to 2.18), urinary tract (SIR 1.61, 95% CI 1.23 to 2.06) when compared with other non-hematological malignancies in post-ibrutinib cohort. Conclusions: Our study results suggest the relative survival rates have increased since the approval of ibrutinib for mantle cell lymphoma patients. Additionally, for some unclear reasons, the incidence of SPM’s (non-hematological malignancies), mainly cancers of the respiratory tract, urinary tract, have increased in the six years following the approval of ibrutinib. Further studies should be conducted to determine the cause of these findings.

Keywords: mantle cell lymphoma, Ibrutinib, relative survival analysis, secondary primary cancers

Procedia PDF Downloads 183
300 Estimation of Morbidity Level of Industrial Labour Conditions at Zestafoni Ferroalloy Plant

Authors: M. Turmanauli, T. Todua, O. Gvaberidze, R. Javakhadze, N. Chkhaidze, N. Khatiashvili

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Background: Mining process has the significant influence on human health and quality of life. In recent years the events in Georgia were reflected on the industry working process, especially minimal requirements of labor safety, hygiene standards of workplace and the regime of work and rest are not observed. This situation is often caused by the lack of responsibility, awareness, and knowledge both of workers and employers. The control of working conditions and its protection has been worsened in many of industries. Materials and Methods: For evaluation of the current situation the prospective epidemiological study by face to face interview method was conducted at Georgian “Manganese Zestafoni Ferroalloy Plant” in 2011-2013. 65.7% of employees (1428 bulletin) were surveyed and the incidence rates of temporary disability days were studied. Results: The average length of a temporary disability single accident was studied taking into consideration as sex groups as well as the whole cohort. According to the classes of harmfulness the following results were received: Class 2.0-10.3%; 3.1-12.4%; 3.2-35.1%; 3.3-12.1%; 3.4-17.6%; 4.0-12.5%. Among the employees 47.5% and 83.1% were tobacco and alcohol consumers respectively. According to the age groups and years of work on the base of previous experience ≥50 ages and ≥21 years of work data prevalence respectively. The obtained data revealed increased morbidity rate according to age and years of work. It was found that the bone and articulate system and connective tissue diseases, aggravation of chronic respiratory diseases, ischemic heart diseases, hypertension and cerebral blood discirculation were the leading among the other diseases. High prevalence of morbidity observed in the workplace with not satisfactory labor conditions from the hygienic point of view. Conclusion: According to received data the causes of morbidity are the followings: unsafety labor conditions; incomplete of preventive medical examinations (preliminary and periodic); lack of access to appropriate health care services; derangement of gathering, recording, and analysis of morbidity data. This epidemiological study was conducted at the JSC “Manganese Ferro Alloy Plant” according to State program “ Prevention of Occupational Diseases” (Program code is 35 03 02 05).

Keywords: occupational health, mining process, morbidity level, cerebral blood discirculation

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299 CuIn₃Se₅ Colloidal Nanocrystals and Its Ink-Coated Films for Photovoltaics

Authors: M. Ghali, M. Elnimr, G. F. Ali, A. M. Eissa, H. Talaat

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CuIn₃Se₅ material is indexed as ordered vacancy compounds having excellent matching properties with CuInGaSe (CIGS) solar absorber layer. For example, the valence band offset of CuIn₃Se₅ with CIGS is nearly 0.3 eV, and the lattice mismatch is less than 1%, besides the absence of discontinuity in their conduction bands. Thus, CuIn₃Se₅ can work as a passivation layer for repelling holes from CIGS/CdS interface and hence to reduce the interface carriers recombination and consequently enhancing the efficiency of CIGS/CdS solar cells. Theoretically, it was reported earlier that an improvement in the efficiency of p-CIGS-based solar cell with a thin ~100 nm of n-CuIn₃Se₅ layer is expected. Recently, a reported experiment demonstrated significant improvement in the efficiency of Molecular Beam Epitaxy (MBE) grown CIGS solar cells from 13.4 to 14.5% via inserting a thin layer of MBE-grown Cu(In,Ga)₃Se₅ layer at the CdS/CIGS interface. It should be mentioned that CuIn₃Se₅ material in either bulk or thin film form, are usually fabricated by high vacuum physical vapor deposition techniques (e.g., three-source co-evaporation, RF sputtering, flash evaporation, and molecular beam epitaxy). In addition, achieving photosensitive films of n-CuIn₃Se₅ material is important for new hybrid organic/inorganic structures, where inorganic photo-absorber layer, with n-type conductivity, can form n–p junction with organic p-type material (e.g., conductive polymers). A detailed study of the physical properties of CuIn₃Se₅ is still necessary for better understanding of device operation and further improvement of solar cells performance. Here, we report on the low-cost synthesis of CuIn₃Se₅ material in nano-scale size, with an average diameter ~10nm, using simple solution-based colloidal chemistry. In contrast to traditionally grown bulk tetragonal CuIn₃Se₅ crystals using high Vacuum-based technology, our colloidal CuIn₃Se₅ nanocrystals show cubic crystal structure with a shape of nanoparticles and band gap ~1.33 eV. Ink-coated thin films prepared from these nanocrystals colloids; display n-type character, 1.26 eV band gap and strong photo-responsive behavior with incident white light. This suggests the potential use of colloidal CuIn₃Se₅ as an active layer in all-solution-processed thin film solar cells.

Keywords: nanocrystals, CuInSe, thin film, optical properties

Procedia PDF Downloads 152
298 The Closed Cavity Façade (CCF): Optimization of CCF for Enhancing Energy Efficiency and Indoor Environmental Quality in Office Buildings

Authors: Michalis Michael, Mauro Overend

Abstract:

Buildings, in which we spend 87-90% of our time, act as a shelter protecting us from environmental conditions and weather phenomena. The building's overall performance is significantly dependent on the envelope’s glazing part, which is particularly critical as it is the most vulnerable part to heat gain and heat loss. However, conventional glazing technologies have relatively low-performance thermo-optical characteristics. In this regard, during winter, the heat losses due to the glazing part of a building envelope are significantly increased as well as the heat gains during the summer period. In this study, the contribution of an innovative glazing technology, namely Closed Cavity Façade (CCF) in improving energy efficiency and IEQ in office buildings is examined, aiming to optimize various design configurations of CCF. Using Energy Plus and IDA ICE packages, the performance of several CCF configurations and geometries for various climate types were investigated, aiming to identify the optimum solution. The model used for the simulations and optimization process was MATELab, a recently constructed outdoor test facility at the University of Cambridge (UK). The model was previously experimentally calibrated. The study revealed that the use of CCF technology instead of conventional double or triple glazing leads to important benefits. Particularly, the replacement of the traditional glazing units, used as the baseline, with the optimal configuration of CCF led to a decrease in energy consumption in the range of 18-37% (depending on the location). This mainly occurs due to integrating shading devices in the cavity and applying proper glass coatings and control strategies, which lead to improvement of thermal transmittance and g-value of the glazing. Since the solar gain through the façade is the main contributor to energy consumption during cooling periods, it was observed that a higher energy improvement is achieved in cooling-dominated locations. Furthermore, it was shown that a suitable selection of the constituents of a closed cavity façade, such as the colour and type of shading devices and the type of coatings, leads to an additional improvement of its thermal performance, avoiding overheating phenomena and consequently ensuring temperatures in the glass cavity below the critical value, and reducing the radiant discomfort providing extra benefits in terms of Indoor Environmental Quality (IEQ).

Keywords: building energy efficiency, closed cavity façade, optimization, occupants comfort

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297 The Epistemology of Human Rights Cherished in Islamic Law and Its Compatibility with International Law

Authors: Malik Imtiaz Ahmad

Abstract:

Human beings are the super organism granted the gift of consciousness of life by the Almighty God and endowed with an intrinsic legal value to their humanity that shall be guarded and protected respecting dignity regardless of your cultural, religious, race, or physical background; you want to be treated equally for a reason for being human. Islam graces the essential integrity of humanity and confirms the freedom and accountability impact on individuality and the open societal sphere, including the moral, economic, and political aspects. Human Rights allow people to live with dignity, equality, justice, freedom, and peace. The Kantian approach to morality expresses that ethical actions follow universal moral laws. Hence, human rights are based upon the normative approaches setting the international standards to promote, guard, and protect the fundamental rights of the people. Islam is a divine religion commanding human rights based upon the principles of social justice and regulates all facets of the moral and spiritual ethics of Muslims besides bringing balance abreast in the non-Muslims to respect their lives with safety and security and property. The Canon law manifests the faith and equality amongst Christianity, regulating the communal dignity to build and promote the sanctity of Holy life (can. 208 to 223). This concept of the community is developed after the insight of the Islamic 'canon law', which is the code of revelation itself and inseparable from the natural part of the salvation of mankind. The etymology and history of human rights is a polemical debate in a preview of Islamic and Western culture. On the other hand, international law is meticulous about the fundamental part of Conon law that focuses on the communal political, social and economic relationship. The evolving process of human rights is considered to be an exclusive universal thought regarding an open society that forms a legal base for the constituent of international instruments of the protection of Human Rights, viz. UDHR. On the other side, Muslim scholars emphasize that human rights are devolving around Islamic law. Both traditions need a dire explanation of contemporary openness for bringing the harmonious universal law acceptable and applicable to the international communities concerning the anthropology of political, economic, and social aspects of a human being.

Keywords: human rights-based approach (HRBA), human rights in Islam, evolution of universal human rights, conflict in western, Islamic human rights

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