Search results for: perceptual present

Authors: Mohamad Ammar Ayass, Natalya Griko, Victor Pashkov, Wanying Cao, Kevin Zhu, Jin Zhang, Lina Abi Mosleh

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Respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent for coronavirus disease 2019 (COVID-19). Early evidence pointed at the angiotensin-converting enzyme 2 (ACE-2) expressed on the epithelial cells of the lung as the main entry point of SARS-CoV-2 into the cells. The viral entry is mediated by the binding of the Receptor Binding Domain (RBD) of the spike protein that is expressed on the surface of the virus to the ACE-2 receptor. As the number of SARS-CoV-2 variants continues to increase, mutations arising in the RBD of SARS-CoV-2 may lead to the ineffectiveness of RBD targeted neutralizing antibodies. To address this limitation, the objective of this study is to develop a combination of aptamers that target different regions of the RBD, preventing the binding of the spike protein to ACE-2 receptor and subsequent viral entry and replication. A safe and innovative biomedical tool was developed to inhibit viral infection and reduce the harms of COVID-19. In the present study, DNA aptamers were developed against a recombinant trimer S protein using the Systematic Evolution of Ligands by Exponential enrichment (SELEX). Negative selection was introduced at round number 7 to select for aptamers that bind specifically to the RBD domain. A series of 9 aptamers (ADI2010, ADI2011, ADI201L, ADI203L, ADI205L, ADIR68, ADIR74, ADIR80, ADIR83) were selected and characterized with high binding affinity and specificity to the RBD of the spike protein. Aptamers (ADI25, ADI2009, ADI203L) were able to bind and pull down endogenous spike protein expressed on the surface of SARS-CoV-2 virus in COVID-19 positive patient samples and determined by liquid chromatography- tandem mass spectrometry analysis (LC-MS/MS). LC-MS/MS data confirmed that aptamers can bind to the RBD of the spike protein. Furthermore, results indicated that the combination of the 9 best aptamers inhibited the binding of the purified trimer spike protein to the ACE-2 receptor found on the surface of Vero E6 cells. In the same experiment, the combined aptamers displayed a better neutralizing effect than antibodies. The data suggests that the selected aptamers could be used in therapy to neutralize the effect of the SARS-CoV-2 virus by inhibiting the interaction between the RBD and ACE-2 receptor, preventing viral entry into target cells and therefore blocking viral replication.

Keywords: aptamer, ACE-2 receptor, binding inhibitor, COVID-19, spike protein, SARS-CoV-2, treatment

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Authors: Paola Causin, Andrea Aspri, Alessandro Benfenati

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Diffuse Optical Tomography (DOT) is an emergent medical imaging technique which employs NIR light to estimate the spatial distribution of optical coefficients in biological tissues for diagnostic purposes, in a noninvasive and non-ionizing manner. DOT reconstruction is a severely ill-conditioned problem due to prevalent scattering of light in the tissue. In this contribution, we present our research in adopting hybrid knowledgedriven/data-driven approaches which exploit the existence of well assessed physical models and build upon them neural networks integrating the availability of data. Namely, since in this context regularization procedures are mandatory to obtain a reasonable reconstruction [1], we explore the use of neural networks as tools to include prior information on the solution. 2. Materials and Methods The idea underlying our approach is to leverage neural networks to solve PDE-constrained inverse problems of the form 𝒒 ∗ = 𝒂𝒓𝒈 𝒎𝒊𝒏𝒒 𝐃(𝒚, 𝒚̃), (1) where D is a loss function which typically contains a discrepancy measure (or data fidelity) term plus other possible ad-hoc designed terms enforcing specific constraints. In the context of inverse problems like (1), one seeks the optimal set of physical parameters q, given the set of observations y. Moreover, 𝑦̃ is the computable approximation of y, which may be as well obtained from a neural network but also in a classic way via the resolution of a PDE with given input coefficients (forward problem, Fig.1 box ). Due to the severe ill conditioning of the reconstruction problem, we adopt a two-fold approach: i) we restrict the solutions (optical coefficients) to lie in a lower-dimensional subspace generated by auto-decoder type networks. This procedure forms priors of the solution (Fig.1 box ); ii) we use regularization procedures of type 𝒒̂ ∗ = 𝒂𝒓𝒈𝒎𝒊𝒏𝒒 𝐃(𝒚, 𝒚̃)+ 𝑹(𝒒), where 𝑹(𝒒) is a regularization functional depending on regularization parameters which can be fixed a-priori or learned via a neural network in a data-driven modality. To further improve the generalizability of the proposed framework, we also infuse physics knowledge via soft penalty constraints (Fig.1 box ) in the overall optimization procedure (Fig.1 box ). 3. Discussion and Conclusion DOT reconstruction is severely hindered by ill-conditioning. The combined use of data-driven and knowledgedriven elements is beneficial and allows to obtain improved results, especially with a restricted dataset and in presence of variable sources of noise.

Keywords: inverse problem in tomography, deep learning, diffuse optical tomography, regularization

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Authors: Cunyu Zhang

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Through literature review about studies related to tense, it is found that there exist disagreements on the definition and existence of Chinese tense. Influenced by some researches on English language which regard tense as a grammatical category based on the verbal inflections of English, some Chinese researchers claim that there is no tense in Chinese language as there are no verbal inflections involved. Meanwhile, other Chinese researchers hold that Chinese still has tense although its verbs are non-inflectional based on the fact that Chinese lexical expressions can imply temporal meaning. We assume that the reasons for the above disagreements in terms of Chinese tense lie in the fact that all the previous studies prefer to view language “from the below” which means expressions of tense are the core part of these studies. However, there are about 6,000 languages with distinct expressions all over the world. Hence, if the language studies only concentrate on expressions, it must become more difficult to understand the nature of language. By contrast, functions of languages are similar; otherwise, the human beings could not communicate with each other. Therefore, we believe that it is necessary for us to have a theoretical study on Chinese tense within the framework of SFL which holds that language is a system where meaning is the core part while form is just the realization of meaning. In addition, SFL is a general linguistic providing a universal framework for languages all over the world. Therefore, based on Systemic Functional Linguistics, the paper firstly redefines tense as a deictic semantic category for describing the speaker’s temporal location of processes and relevant temporal relations. With reference to this definition, this study explores the meaning system of tense. It is proposed that tense expresses four kinds of meaning, namely interpersonal, experiential, logical and textual meanings. From the interpersonal angle, tense helps to exchange temporal information between the speaker and the listener, and the temporal information refers to the anchoring of a concerned process in the past, present or future by the speaker. From the experiential angle, tense plays a role in the temporal locating of material, mental, relational, existential, behavioral and verbal processes by the speaker. From the logical angle, tense denotes the temporal relations at the two levels of clause and clause complex, and such relations fall into simultaneity, anteriority and posteriority. From the textual angle, tense refers to the temporal relations at the level of text, and the temporal relations in question concern linear serial relations and synchronous serial relations.

Keywords: Chinese, meaning system, Systemic Functional Linguistics, tense

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Authors: Muhammad Saiful Islam Khan, Yun Ji Kim

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Organophosphorus pesticides (OPPs) have been widely used to replace more persistent organochlorine pesticides because OPPs are more soluble in water and decompose rapidly in aquatic systems. Extensive uses of OPPs in modern agriculture are the major cause of the contamination of surface water. Regardless of the advantages gained by the application of pesticides in modern agriculture, they are a threat to the public health environment. With the aim of reducing possible health threats, several physical and chemical treatment processes have been studied to eliminate biological and chemical poisons from food stuff. In the present study, a micro-plasma device was used to reduce pesticides from the surface of food stuff. Pesticide free food items chosen in this study were perilla leaf, tomato, broccoli and blueberry. To evaluate the removal efficiency of pesticides, different washing methods were followed such as soaking with water, washing with bubbling water, washing with plasma-treated water and washing with chlorine water. 2 mL of 2000 ppm pesticide samples, namely, diazinone and chlorpyrifos were individuality inoculated on food surface and was air dried for 2 hours before treated with plasma. Plasma treated water was used in two different manners one is plasma treated water with bubbling the other one is aerosolized plasma treated water. The removal efficiency of pesticides from food surface was studied using HPLC. Washing with plasma treated water, aerosolized plasma treated water and chlorine water shows minimum 72% to maximum 87 % reduction for 4 min treatment irrespective to the types of food items and the types of pesticides sample, in case of soaking and bubbling the reduction is 8% to 48%. Washing with plasma treated water, aerosolized plasma treated water and chlorine water shows somewhat similar reduction ability which is significantly higher comparing to the soaking and bubbling washing system. The temperature effect of the washing systems was also evaluated; three different temperatures were set for the experiment, such as 22°C, 10°C and 4°C. Decreasing temperature from 22°C to 10°C shows a higher reduction in the case of washing with plasma and aerosolized plasma treated water, whereas an opposite trend was observed for the washing with chlorine water. Further temperature reduction from 10°C to 4°C does not show any significant reduction of pesticides, except for the washing with chlorine water. Chlorine water treatment shows lesser pesticide reduction with the decrease in temperature. The color changes of the treated sample were measured immediately and after one week to evaluate if there is any effect of washing with plasma treated water and with chlorine water. No significant color changes were observed for either of the washing systems, except for broccoli washing with chlorine water.

Keywords: chlorpyrifos, diazinone, pesticides, micro plasma

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Authors: Gabriel Michel

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The aim of our research is to find solutions for adapting university teaching to today's students and companies. To achieve this, we have tried to change the posture and behavior of those involved in the learning situation by promoting other skills. There is a gap between the expectations and functioning of students and university teaching. At the same time, the business world needs employees who are obviously competent and proficient in technology, but who are also imaginative, flexible, able to communicate, learn on their own and work in groups. These skills are rarely developed as a goal at university. The flipped classroom has been one solution. Thanks to digital tools such as Moodle, for example, but the model behind them is still centered on teachers and classic learning scenarios: it makes course materials available without really involving them and encouraging them to cooperate. It's against this backdrop that we've conducted action research to explore the possibility of changing the way we learn (rather than teach) by changing the posture of both the classic student and the teacher. We hypothesized that a tool we developed would encourage autonomy, the possibility of progressing at one's own pace, collaboration and learning using all available resources(other students, course materials, those on the web and the teacher/facilitator). Experimentation with this tool was carried out with around thirty German and French first-year students at the Université de Lorraine in Metz (France). The projected changesin the groups' learning situations were as follows: - use the flipped classroom approach but with a few traditional presentations by the teacher (materials having been put on a server) and lots of collective case solving, - engage students in their learning by inviting them to set themselves a primary objective from the outset, e.g. “Assimilating 90% of the course”, and secondary objectives (like a to-do list) such as “create a new case study for Tuesday”, - encourage students to take control of their learning (knowing at all times where they stand and how far they still have to go), - develop cooperation: the tool should encourage group work, the search for common solutions and the exchange of the best solutions with other groups. Those who have advanced much faster than the others, or who already have expertise in a subject, can become tutors for the others. A student can also present a case study he or she has developed, for example, or share materials found on the web or produced by the group, as well as evaluating the productions of others, - etc… A questionnaire and analysis of assessment results showed that the test group made considerable progress compared with a similar control group. These results confirmed our hypotheses. Obviously, this tool is only effective if the organization of teaching is adapted and if teachers are willing to change the way they work.

Keywords: pedagogy, cooperation, university, learning environment

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Authors: Wu Chao

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The urban design of the new district in China is different from other existing cities at the city planning level, including Beijing, Shanghai, Guangzhou, etc. And the urban problems of these super-cities are same as many big cities around the world. The goal of the new district construction plan is to enable people to live comfortably, to improve the well-being of residents, and to create a way of life different from that of other urban communities. To avoid the emergence of the super community, the idea of "decentralization" is taken as the overall planning idea, and the function and form of each community are set up with a homogeneous allocation of resources so that the community can grow naturally. Similar to the growth of vines in nature, each community groups are independent and connected through roads, with clear community boundaries that limit their unlimited expansion. With a community contained 20,000 people as a case, the community is a mixture for living, production, office, entertainment, and other functions. Based on the development of the Internet, to create more space for public use, and can use data to allocate resources in real time. And this kind of shared space is the main part of the activity space in the community. At the same time, the transformation of spatial function can be determined by the usage feedback of all kinds of existing space, and the use of space can be changed by the changing data. Take the residential unit as the basic building function mass, take the lower three to four floors of the building as the main flexible space for use, distribute functions such as entertainment, service, office, etc. For the upper living space, set up a small amount of indoor and outdoor activity space, also used as shared space. The transformable space of the bottom layer is evenly distributed, combined with the walking space connected the community, the service and entertainment network can be formed in the whole community, and can be used in most of the community space. With the basic residential unit as the replicable module, the design of the other residential units runs through the idea of decentralization and the concept of the vine community, and the various units are reasonably combined. At the same time, a small number of office buildings are added to meet the special office needs. The new functional mixed community can change many problems of the present city in the future construction, at the same time, it can keep its vitality through the adjustment function of the Internet.

Keywords: decentralization, mixed functional community, shared space, spatial usage data

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Authors: Ella Sever, Irena Glažar, Ema Saltović

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Conventional cigarette smoking is associated with an increased risk of oral diseases and oral symptoms such as dry mouth, bad breath, burning sensation, and changes in taste sensation. The harmful effects of conventional cigarette smoking on oral health have been extensively studied previously. However, there is a severe lack of studies investigating the effects of Tobacco Heating System (THS) on oral structures. As a preventive measure, a new alternative Tobacco THS has been developed, and according to the manufacturer, it has fewer potentially harmful and harmful constituents and consequently, lowers the risk of developing tobacco-related diseases. The aim is to analyze the effects of conventional cigarettes and THS on salivary flow rate (SFR), and self-reported oral symptoms.The stratified cross-sectional study included 90 subjects divided into three groups: THS smokers, conventional cigarette smokers, and nonsmokers. The subjects completed questionnaires on smoking habits, and symptoms (dry mouth, bad breath, burning sensation, and changes in taste sensation). SFR test were performed on each subject. The lifetime exposure to smoking was calculated using the Brinkman index (BI). Participants were 20-55 years old (median 31), and 66.67 % were female. The study included three groups of equal size (n = 20), and no statistically significant differences were found between the groups in terms of age (p = 0.632), sex (p = 1.0), and lifetime exposure to smoking (the BI) (p=0,129). Participants from the smoking group had an average of 10 (2-30) years of smoking experience in the conventional cigarettes group and 6 (1-20) years of smoking experience in the THS group. Daily consumption of cigarettes/heets per day was the same for both smokers’ groups (12(2-20) cigarettes/heets per day). The self-reported symptoms were present in 40 % of participants in the smokers group. There were significant differences in the presence of halitosis (p = 0.025) and taste sensation (p=0.013). There were no statistical differences in the presence of dry mouth (p =0.416) and burning sensation (0.7). The SFR differed between groups (p < 0.001) and was significantly lower in the THS and conventional cigarette smokers’ groups than the nonsmokers’ group. There were no significant differences between THS smokers and conventional cigarette smokers. The results of the study show that THS products have a similar effect to conventional cigarettes on oral cavity structures, especially in terms of SFR, self-reported halitosis, and changes in taste.

Keywords: oral health, tobacco products, halitosis, cigarette smoking

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Authors: Bineet Kumar

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Many civil engineering infrastructures frequently encounter repetitive loading during their service life. Due to the inherent complexity observed in concrete, like quasi-brittle materials, understanding the fatigue behavior in concrete still posesa challenge. Moreover, the fracture process zone characteristics ahead of the crack tip have been observed to be different in fatigue loading than in the monotonic cases. Therefore, it is crucial to comprehend the energy dissipation associated with the fracture process zone (FPZ) due to repetitive loading. It is well known that stiffness degradation due to cyclic loadingprovides a better understanding of the fracture behavior of concrete. Under repetitive load cycles, concrete members exhibit a two-stage stiffness degradation process. Experimentally it has been observed that the stiffness decreases initially with an increase in crack length and subsequently increases. In this work, an attempt has been made to propose an analytical expression to predict energy dissipation and later the stiffness degradation as a function of crack length. Three-point bend specimens have been considered in the present work to derive the formulations. In this approach, the expression for the resultant stress distribution below the neutral axis has been derived by correlating the bending stress with the cohesive stresses developed ahead of the crack tip due to the existence of the fracture process zone. This resultant stress expression is utilized to estimate the dissipated energydue to crack propagation as a function of crack length. Further, the formulation for the stiffness degradation has been developed by relating the dissipated energy with the work done. It can be used to predict the critical crack length and fatigue life. An attempt has been made to understand the influence of stress amplitude on the damage pattern by using the information on the rate of stiffness degradation. It has been demonstrated that with the increase in the stress amplitude, the damage/FPZ proceeds more in the direction of crack propagation compared to the damage in the direction parallel to the span of the beam, which causes a lesser rate of stiffness degradation for the incremental crack length. Further, the effect of loading frequency has been investigated in terms of stiffness degradation. Under low-frequency loading cases, the damage/FPZ has been found to spread more in the direction parallel to the span, in turn reducing the critical crack length and fatigue life. In such a case, a higher rate of stiffness degradation has been observed in comparison to the high-frequency loading case.

Keywords: fatigue life, fatigue, fracture, concrete

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Authors: Konrad Steyn, Jacques Laubscher

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South African urban design solutions are mostly aligned with European and North American models that are often not appropriate in addressing some of this country’s challenges such as multiculturalism and decaying urban areas. Sustainable urban redevelopment in South Africa should be comprehensive in nature, sensitive in its manifestation, and should be robust and inclusive in order to achieve social relevance. This paper argues that the success of an urban design intervention is largely dependent on the public’s perceptions and expectations, and the way people participate in shaping their environments. The concept of sustainable urbanism is thus more comprehensive than – yet should undoubtedly include – methods of construction, material usage and climate control principles. The case study is a central element of this research paper. 725 Arcadia Street in Pretoria, was originally commissioned as a food market structure. A starkly contrasting existing modernist adjacent building forms the morphological background. Built in 1969, it is a valuable part of Pretoria’s modernist fabric. It was realised early on that the project should not be a mere localised architectural intervention, but rather an occasion to revitalise the neighbourhood through urban regeneration. Because of the complex and comprehensive nature of the site and rich cultural diversity of the area, a multi-faceted approach seemed the most appropriate response. The methodology for collating data consisted of a combination of literature reviews (regarding the historic original fauna and flora and current plants, observation (frequent site visits) and physical surveying on the neighbourhood level (physical location, connectivity to surrounding landmarks as well as movement systems and pedestrian flows). This was followed by an exploratory design phase, culminating in the present redevelopment proposal. Since built environment interventions are increasingly based on generalised normative guidelines, an approach focusing of urban acupuncture could serve as an alternative. Celebrating the specific urban condition, urban acupuncture offers an opportunity to influence the surrounding urban fabric and achieve urban renewal through physical, social and cultural mediation.

Keywords: neighbourhood, urban renewal, South African urban design solutions, sustainable urban redevelopment

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Authors: Jithin S. Kumar, Ramesh Kannan Kandasami

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Geomaterials are generally porous in nature due to the presence of discrete particles and interconnected voids. The porosity present in these geomaterials play a critical role in many engineering applications such as CO2 sequestration, well bore strengthening, enhanced oil and hydrocarbon recovery, hydraulic fracturing, and subsurface waste storage. These applications involves solid-fluid interactions, which govern the changes in the porosity which in turn affect the permeability and stiffness of the medium. Injecting fluid into the geomaterials results in permeation which exhibits small or negligible deformation of the soil skeleton followed by cavity expansion/ fingering/ fracturing (different forms of instabilities) due to the large deformation especially when the flow rate is greater than the ability of the medium to permeate the fluid. The complexity of this problem increases as the geomaterial behaves like a solid and fluid under certain conditions. Thus it is important to understand this multiphysics problem where in addition to the permeation, the elastic-plastic deformation of the soil skeleton plays a vital role during fluid injection. The phenomenon of permeation and cavity expansion in porous medium has been studied independently through extensive experimental and analytical/ numerical models. The analytical models generally use Darcy's/ diffusion equations to capture the fluid flow during permeation while elastic-plastic (Mohr-Coulomb and Modified Cam-Clay) models were used to predict the solid deformations. Hitherto, the research generally focused on modelling cavity expansion without considering the effect of injected fluid coming into the medium. Very few studies have considered the effect of injected fluid on the deformation of soil skeleton. However, the porosity changes during the fluid injection and coupled elastic-plastic deformation are not clearly understood. In this study, the phenomenon of permeation and instabilities such as cavity and finger/ fracture formation will be quantified extensively by performing experiments using a novel experimental setup in addition to utilizing image processing techniques. This experimental study will describe the fluid flow and soil deformation characteristics under different boundary conditions. Further, a well refined coupled semi-analytical model will be developed to capture the physics involved in quantifying the deformation behaviour of geomaterial during fluid injection.

Keywords: solid-fluid interaction, permeation, poroelasticity, plasticity, continuum model

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Authors: Balthazar Temu, Zhao Yan, Bogdan-Petrin Ratiu, Sang Soon Oh, Qiang Li

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Photonic crystal surface emitting lasers (PCSELs) has recently become an area of active research because of the advantages these lasers have over the edge emitting lasers and vertical cavity surface emitting lasers (VCSELs). PCSELs can emit laser beams with high power (from the order of few milliwatts to Watts or even tens of Watts) which scales with the emission area while maintaining single mode operation even at large emission areas. Most PCSELs reported in the literature are air-hole based, with only few demonstrations of nanowire based PCSELs. We previously reported an optically pumped, nanowire based PCSEL operating in the O band by using the honeycomb lattice. The nanowire based PCSELs have the advantage of being able to grow on silicon platform without threading dislocations. It is desirable to extend their operating wavelength to C band to open more applications including eye-safe sensing, lidar and long haul optical communications. In this work we first analyze how the lattice constant , nanowire diameter, nanowire height and side length of the hexagon in the honeycomb pattern can be changed to increase the operating wavelength of the honeycomb based PCSELs to the C band. Then as an attempt to make our device electrically pumped, we present the finite-difference time-domain (FDTD) simulation results with metals on the nanowire. The results for different metals on the nanowire are presented in order to choose the metal which gives the device with the best quality factor. The metals under consideration are those which form good ohmic contact with p-type doped InGaAs with low contact resistivity and decent sticking coefficient to the semiconductor. Such metals include Tungsten, Titanium, Palladium and Platinum. Using the chosen metal we demonstrate the impact of thickness of the metal for a given nanowire height on the quality factor of the device. We also investigate how the height of the nanowire affects the quality factor for a fixed thickness of the metal. Finally, the main steps in making the practical device are discussed.

Keywords: designing nanowire PCSEL, designing PCSEL on silicon substrates, low threshold nanowire laser, simulation of photonic crystal lasers.

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Authors: Yakubu Adamu, Baba Alfa, Salahudeen Adamu Gene

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As the drive towards clean, renewable and sustainable energy generation is gradually been reshaped by renewable penetration over time, energy storage has thus, become an optimal solution for utilities looking to reduce transmission and capacity cost, therefore the need for capacity resources to be adjusted accordingly such that renewable energy storage may have the opportunity to substitute for retiring conventional energy systems with higher capacity factors. Considering the Nigeria scenario, where Over 80% of the current Nigerian primary energy consumption is met by petroleum, electricity demand is set to more than double by mid-century, relative to 2025 levels. With renewable energy penetration rapidly increasing, in particular biomass, hydro power, solar and wind energy, it is expected to account for the largest share of power output in the coming decades. Despite this rapid growth, the imbalance between load and resources has created a hindrance to the development of energy storage capacity, load and resources, hence forecasting energy storage capacity will therefore play an important role in maintaining the balance between load and resources including supply and demand. Therefore, the degree to which this might occur, its timing and more importantly its sustainability, is the subject matter of the current research. Here, we forecast the future energy storage capacity rating and thus, evaluate the load and resource scenario in Nigeria. In doing so, We used the scenario-based International Energy Agency models, the projected energy demand and supply structure of the country through 2030 are presented and analysed. Overall, this shows that in high renewable (solar) penetration scenarios in Nigeria, energy storage with 4-6h duration can obtain over 86% capacity rating with storage comprising about 24% of peak load capacity. Therefore, the general takeaway from the current study is that most power systems currently used has the potential to support fairly large penetrations of 4-6 hour storage as capacity resources prior to a substantial reduction in capacity ratings. The data presented in this paper is a crucial eye-opener for relevant government agencies towards developing these energy resources in tackling the present energy crisis in Nigeria. However, if the transformation of the Nigeria. power system continues primarily through expansion of renewable generation, then longer duration energy storage will be needed to qualify as capacity resources. Hence, the analytical task from the current survey will help to determine whether and when long-duration storage becomes an integral component of the capacity mix that is expected in Nigeria by 2030.

Keywords: capacity, energy, power system, storage

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Authors: Chumki Payun, Bidisha Som

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The Mising language, spoken by the Mising community in Assam, belongs to the Tibeto-Burman family of languages. This is one of the smaller languages of the region and is facing endangerment due to the dominance of the larger languages, like Assamese. The language is spoken in close in-group scenarios and is gradually losing ground to the dominant languages, partly also due to the education setup where schools use only dominant languages. While there are a number of factors for the current contemporary status of the language, and those can be studied using sociolinguistic tools, the current work aims to contribute to the understanding of language attrition through language processing in order to establish if the effect of second language dominance is more than mere ‘usage’ patterns and has an impact on cognitive strategies. When bilingualism spreads widely in society and results in a language shift, speakers perform people often do better in their second language (L2) than in their first language (L1) across a variety of task settings, in both comprehension and production tasks. This phenomenon was investigated in the case of Mising-Assamese bilinguals, using a picture naming task, in two districts of Jorhat and Tinsukia in Assam, where the relative dominance of L2 is slightly different. This explorative study aimed to investigate if the L2 dominance is visible in their performance and also if the pattern is different in the two different places, thus pointing to the degree of language loss in this case. The findings would have implications for native language education, as education in one’s mother tongue can help reverse the effect of language attrition helping preserve the traditional knowledge system. The hypothesis was that due to the dominance of the L2, subjects’ performance in the task would be better in Assamese than that of Missing. The experiment: Mising-Assamese bilingual participants (age ranges 21-31; N= 20 each from both districts) had to perform a picture naming task in which participants were shown pictures of familiar objects and asked to name them in four scenarios: (a) only in Mising; (b) only in Assamese; (c) a cued mix block: an auditory cue determines the language in which to name the object, and (d) non-cued mix block: participants are not given any specific language cues, but instructed to name the pictures in whichever language they feel most comfortable. The experiment was designed and executed using E-prime 3.0 and was conducted responses were recorded using the help of a Chronos response box and was recorded with the help of a recorder. Preliminary analysis reveals the presence of dominance of L2 over L1. The paper will present a comparison of the response latency, error analysis, and switch cost in L1 and L2 and explain the same from the perspective of language attrition.

Keywords: bilingualism, language attrition, language processing, Mising language.

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Authors: Tatiani D. Mousoura

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Specific learning disability (SLD) in higher education has been partially explored in Greece so far. Moreover, opinions on professional perspectives for university students with SLD, is scarcely encountered in Greek research. The perceptions of the hidden character of SLD along with the university policy towards it and professional perspectives that result from this policy have been examined in the present research. This study has applied the paradigm of a Greek Tertiary Pedagogical Education Department (Early Childhood Education). Via mixed methods, data have been collected from different groups of people in the Pedagogical Department: students with SLD and without SLD, academic staff and administration staff, all of which offer the opportunity for triangulation of the findings. Qualitative methods include ten interviews with students with SLD and 15 interviews with academic staff and 60 hours of observation of the students with SLD. Quantitative methods include 165 questionnaires completed by third and fourth-year students and five questionnaires completed by the administration staff. Thematic analyses of the interviews’ data and descriptive statistics on the questionnaires’ data have been applied for the processing of the results. The use of medical terms to define and understand SLD was common in the student cohort, regardless of them having an SLD diagnosis. However, this medical model approach is far more dominant in the group of students without SLD who, by majority, hold misconceptions on a definitional level. The academic staff group seems to be leaning towards a social approach concerning SLD. According to them, diagnoses may lead to social exclusion. The Pedagogical Department generally endorses the principles of inclusion and complies with the provision of oral exams for students with SLD. Nevertheless, in practice, there seems to be a lack of regular academic support for these students. When such support does exist, it is only through individual initiatives. With regards to their prospective profession, students with SLD can utilize their personal experience, as well as their empathy; these appear to be unique weapons in their hands –in comparison with other educators− when it comes to teaching students in the future. In the Department of Pedagogy, provision towards SLD results sporadic, however the vision of an inclusive department does exist. Based on their studies and their experience, pedagogy students with SLD claim that they have an experiential internalized advantage for their future career as educators.

Keywords: specific learning disability, SLD, dyslexia, pedagogy department, inclusion, professional role of SLDed educators, higher education, university policy

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Authors: Elissavet Feloni, Ioannis Kourtis, Konstantinos Kotsifakis, Evangelos Baltas

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Water inadequacy in small dry islands scattered in the Aegean Sea (Greece) is a major problem regarding Water Resources Management (WRM), especially during the summer period due to tourism. In the present work, various WRM schemes are designed and presented. The WRM schemes take into account current infrastructure and include Rainwater Harvesting tanks and Reverse Osmosis Desalination Units. The energy requirements are covered mainly by wind turbines and/or a seawater pumped storage system. Sizing is based on the available data for population and tourism per island, after taking into account a slight increase in the population (up to 1.5% per year), and it guarantees at least 80% reliability for the energy supply and 99.9% for potable water. Evaluation of scenarios is carried out from a financial perspective, after calculating the Life Cycle Cost (LCC) of each investment for a lifespan of 30 years. The wind-powered desalination plant was found to be the most cost-effective practice, from an economic point of view. Finally, in order to estimate the Climate Change (CC) impact, six different CC scenarios were investigated. The corresponding rate of on-grid versus off-grid energy required for ensuring the targeted reliability for the zero and each climatic scenario was investigated per island. The results revealed that under CC the grid-on energy required would increase and as a result, the reduction in wind turbines and seawater pumped storage systems’ reliability will be in the range of 4 to 44%. However, the range of this percentage change does not exceed 22% per island for all examined CC scenarios. Overall, CC is proposed to be incorporated into the design process for WRM-related projects. Acknowledgements: This research is co-financed by Greece and the European Union (European Social Fund - ESF) through the Operational Program «Human Resources Development, Education and Lifelong Learning 2014-2020» in the context of the project “Development of a combined rain harvesting and renewable energy-based system for covering domestic and agricultural water requirements in small dry Greek Islands” (MIS 5004775).

Keywords: small dry islands, water resources management, climate change, desalination, RES, seawater pumped storage system, rainwater harvesting

Procedia PDF Downloads 117

Authors: Ryoma Tokonami, Teruya Goto, Tatsuhiro Takahashi,

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For enhancing the mechanical property ofcarbon fiber reinforced plastic (CFRP), the surface modification of carbon fiber (CF) by multi-walled carbon nanotube (MWCNT) has received considerable attention using direct MWCNT growth on CF with a catalysis, MWCNT electrophoresis, and layer-by-layer of MWCNT with reactive polymers, etc. Among above approaches, the layer-by-layer method is the simplest process, however, the amount of MWCNTs on CF is very little, resulting in the small amount of improvement of the mechanical property of the composite. The remaining amount of MWCNT on CF after melt mixing of CF (short fiber) with thermoplastic matrix polymer was not examined clearly in the former studies. The present research aims to propose an effective layer-by-layer chemical grafting of a highly reactive oxazoline polymer, which has not been used before, and MWCNTs onto CF using the highly reactivity of oxazoline and COOH on the surface of CF and MWCNTs.With layer-by-layer method, the first uniform chemically bonded mono molecular layer on carbon fiber was formed by chemical surface reaction of carbon fiber, a reactive oxazoline polymer solution between COOH of carbon fiber and oxazoline. The second chemically bonded uniform layer of MWCNTs on the first layer was prepared through the first layer coated carbon fiber in MWCNT dispersion solution by chemical reaction between oxazoline and COOH of MWCNTs. The quantitative analysis of MWCNTs on carbon fiber was performed, showing 0.44 wt.% of MWCNTs based on carbon fiber, which is much larger amount compared with the former studies in layer-by-layer method. In addition, MWCNTs were also observed uniform coating on carbon fiber by scanning electron micrograph (SEM). Carbon fiber composites were prepared by melting mixing using polystyrene (PS) as a thermoplastic matrix because of easy removal of PS by solvent for additional analysis, resulting the 20% of enhancement of tensile strength and modulus by tensile strength test. It was confirmed bySEM the layer-by-layer structure on carbon fibers were remained after the melt mixing by removing PS with a solvent. As a conclusion, the effectiveness for the enhancement of the mechanical properties of CF(short fiber)/PS composite using the highly reactive oxazoline polymer for the first layer and MWCNT for the second layer, which act as the physical anchor, was demonstrated.

Keywords: interface, layer-by-layer, multi walled carbon nanotubes (MWCNTs), oxazoline

Procedia PDF Downloads 203

Authors: Takaaki Miyabe, Hideharu Takahashi, Hiroshige Kikura

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The Government of Japan and Tokyo Electric Power Company Holdings, Incorporated (TEPCO) are struggling with the decommissioning of Fukushima Daiichi Nuclear Power Plants, especially fuel debris retrieval. In fuel debris retrieval, amount of fuel debris, location, characteristics, and distribution information are important. Recently, a survey was conducted using a robot with a small camera. Progress report in remote robot and camera research has speculated that fuel debris is present both at the bottom of the Pressure Containment Vessel (PCV) and inside the Reactor Pressure Vessel (RPV). The investigation found a 'tie plate' at the bottom of the containment, this is handles on the fuel rod. As a result, it is assumed that a hole large enough to allow the tie plate to fall is opened at the bottom of the reactor pressure vessel. Therefore, exploring the existence of holes that lead to inside the RCV is also an issue. Investigations of the lower part of the RPV are currently underway, but no investigations have been made inside or above the PCV. Therefore, a survey must be conducted for future fuel debris retrieval. The environment inside of the RPV cannot be imagined due to the effect of the melted fuel. To do this, we need a way to accurately check the internal situation. What we propose here is the adaptation of a technology called 'Structure from Motion' that reconstructs a 3D image from multiple photos taken by a single camera. The plan is to mount a monocular camera on the tip of long-arm robot, reach it to the upper part of the PCV, and to taking video. Now, we are making long-arm robot that has long-arm and used at high level radiation environment. However, the environment above the pressure vessel is not known exactly. Also, fog may be generated by the cooling water of fuel debris, and the radiation level in the environment may be high. Since camera alone cannot provide sufficient sensing in these environments, we will further propose using ultrasonic measurement technology in addition to cameras. Ultrasonic sensor can be resistant to environmental changes such as fog, and environments with high radiation dose. these systems can be used for a long time. The purpose is to develop a system adapted to the inside of the containment vessel by combining a camera and an ultrasound. Therefore, in this research, we performed a basic experiment on 3D image reconstruction using a camera and ultrasound. In this report, we select the good and bad condition of each sensing, and propose the reconstruction and detection method. The results revealed the strengths and weaknesses of each approach.

Keywords: camera, image processing, reconstruction, ultrasound

Procedia PDF Downloads 104

Authors: Arzu K. Harmanci Seren, Feride Eskin Bacaksiz

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The shortage of nursing personnel is considered one of the most important labour force issues in health sector of developed countries since early 1970s. International Labour Organization developed standards for working conditions of nurses in collaboration with World Health Organization with the aim of helping to solve nursing shortage problem all over the world. As a result of this collaboration, ILO Nursing Personnel Convention (C. 149), and the accompanying Recommendation (R. 157) were adopted in 1977. Turkey as a country that has a serious nurse shortage problem, has been a member of ILO since 1932, and has not signed this convention yet. This study was planned to compare some of the working standards in Convention with the present working conditions of nurses in Turkey. The data were collected by an on line survey between 19 January-16 February 2015 for this cross-sectional study. Participants were reached through social network accounts in collaboration with nursing associations. Totally 828 nurses from the 57 provinces of Turkey participated in the study. Survey was consisted of 14 open ended questions related to working conditions of nurses and 34 Likert statements related to nursing policies of the facilities they are working in. The data were analysed using the IBM SPSS 21.0 (licensed to Istanbul University) software. Descriptive and comparative statistics were performed. Most of the participants (81.5%) were staff and 18.5% of them were manager nurses. Most of them had baccalaureate (57.9%) or master (27.4%) degree in nursing. 18.5% of the participants were working in private hospitals, 34.9% of them in university hospitals and 46.6% of them were in Ministry of Health Hospitals. It was found that monthly working schedules were announced mostly 7 days ago (18%), working time of nurses was at least 8 hours (41.5%) and at most 24 hours (22.8%) in a day and had time for lunch or dinner 25.18 (SD=16.66), for resting 21.02 (SD=29.25) minutes. On the other hand, it was determined that 316 (43.2%) nurses did not have time for lunch and 61 (7.9%) of them could not find time for eating anything. It was also explored they were working 15-96 hours in a week (mean=48.28, SD=8.89 hours), 4-29 days in a month (mean=19.29, SD=5.03 days) and 597 (72%) nurses overworked changing form 1 hour to 150 hours (32.80, SD=23.42 hours) before the month in which surveys were filled. Most of the participants did not leave the job due to the sickness (47.5%) even if they felt sick. Also most of them did not leave the job due to any excuse (67.2%) or education (57.3%). This study has significance because of nurses from different provinces participated in and it provides brief information about the working conditions of nurses nationwide. It was explored that nurses in Turkey were working at worse conditions according the International Labour Organization’s recommendations.

Keywords: nurse, international labour organization, recommendations for nurses, working conditions

Procedia PDF Downloads 253

Authors: Joudia Akil, Stephane Siffert, Laurence Pirault-Roy, Renaud Cousin, Christophe Poupin

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The CO2 emitted from anthropic activities is perceived as a constraint in industrial activity due to taxes, stringent environmental regulations, impact on global warming… To limit these CO2 emissions, reuse of CO2 represents a promising alternative, with important applications in chemical industry and for power generation. However, CO2 valorization process requires a gas as pure as possible Oxyfuel-combustion that enables obtaining a CO2 rich stream, with water vapor (10%) is then interesting. Nevertheless to decrease the amount of the by-products found with the CO2 (especially CO and NOx which are harmful to the environment) a catalytic treatment must be applied. Nowadays three-way catalysts are well-developed material for simultaneous conversion of unburned hydrocarbons, carbon monoxide (CO) and nitrogen oxides (NOx). The use of Pd attracted considerable attention on the basis of economic factors (the high cost and scarcity of Pt and Rh). This explains the large number of studies concerning the CO-NO reaction on Pd in the recent years. In the present study, we will compare a series of Pd materials supported on different oxides for CO2 purification from the oxyfuel combustion system, by reducing NO with CO in an oxidizing environment containing CO2 rich stream and presence of 8.2% of water. Al2O3, CeO2, MgO, SiO2 and TiO2 were used as support materials of the catalysts. 1wt% Pd/Support catalysts were obtained by wet impregnation on supports with a precursor of palladium [Pd(acac)2]. The obtained samples were subsequently characterized by H2 chemisorption, BET surface area and TEM. Finally, their catalytic performances were evaluated in CO2 purification which is carried out in a fixed-bed flow reactor containing 150 mg of catalyst at atmospheric pressure. The flow of the reactant gases is composed of: 20% CO2, 10% O2, 0.5% CO, 0.02% NO and 8.2% H2O (He as eluent gas) with a total flow of 200mL.min−1, in the same GHSV. The catalytic performance of the Pd catalysts for CO2 purification revealed that: -The support material has a strong influence on the catalytic activity of 1wt.% Pd supported catalysts. depending of the nature of support, the Pd-based catalysts activity changes. -The highest reduction of NO with CO is obtained in the following ranking: TiO2>CeO2>Al2O3. -The supports SiO2 and MgO should be avoided for this reaction, -Total oxidation of CO occurred over different materials, -CO2 purification can reach 97%, -The presence of H2O has a positive effect on the NO reduction due to the production of the reductant H2 from WGS reaction H2O+CO → H2+CO2

Keywords: carbon dioxide, environmental chemistry, heterogeneous catalysis, oxyfuel combustion

Procedia PDF Downloads 255

Authors: Seemabahen Dave, Maria Varua, Basant Maheshwari, Roger Packham

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The declining groundwater levels and quality are acknowledged to be affecting the well-being of farmers especially those located in the semi-arid regions where groundwater is the only source of water for domestic and agricultural use. Further, previous studies have identified the need to examine the quality of life of farmers beyond economic parameters and for a shift in setting rural development policy goals to the perspective of beneficiaries. To address these gaps, this paper attempts to ascertain the subjective wellbeing of farmers from two semi-arid regions of India. The study employs the integrated conceptual framework for the assessment of individual and regional subjective wellbeing developed by Larson in 2009 at Australia. The method integrates three domains i.e. society, natural environment and economic services consisting of 37 wellbeing factors. The original set of 27 revised wellbeing factors identified by John Ward is further revised in current study to make it more region specific. Generally, researchers in past studies select factors of wellbeing based on literature and assign the weights arbitrary. In contrast, the present methodology employs a unique approach by asking respondents to identify the factors most important to their wellbeing and assign weights of importance based on their responses. This method minimises the selection bias and assesses the wellbeing from farmers’ perspectives. The primary objectives of this study are to identify key wellbeing attributes and to assess the influence of groundwater on subjective wellbeing of farmers. Findings from 507 farmers from 11 villages of two watershed areas of Rajasthan and Gujarat, India chosen randomly and were surveyed using a structured face-to-face questionnaire are presented in this paper. The results indicate that significant differences exist in the ranking of wellbeing factors at individual, village and regional levels. The top five most important factors in the study areas include electricity, irrigation infrastructure, housing, land ownership, and income. However, respondents are also most dissatisfied with these factors and correspondingly perceive a high influence of groundwater on them. The results thus indicate that intervention related to improvement of groundwater availability and quality will greatly improve the satisfaction level of well-being factors identified by the farmers.

Keywords: groundwater, farmers, semi-arid regions, subjective wellbeing

Procedia PDF Downloads 260

Authors: Yenisleidy Martinez Martinez, Yannay Casas-Ledon, Jo Dewulf

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The ecosystem services (ES) concept has contributed to draw attention to the benefits ecosystems generate for people and how necessary natural resources are for human well-being. The identification and prioritization of the ES constitute the first steps to undertake conservation and valuation initiatives on behalf of people. Additionally, mapping the supply of ES is a powerful tool to support decision making regarding the sustainable management of landscape and natural resources. In this context, the present study aimed to identify, prioritize and map the primary ES in Biobio and Nuble regions using a methodology that combines expert judgment, multi-attribute evaluation methods, and Geographic Information Systems (GIS). Firstly, scores about the capacity of different land use/cover types to supply ES and the importance attributed to each service were obtained from experts and stakeholders via an online survey. Afterward, the ES assessment matrix was constructed, and the weighted linear combination (WLC) method was applied to mapping the overall capacity of supply of provisioning, regulating and maintenance, and cultural services. Finally, prioritized ES for the study area were selected and mapped. The results suggest that native forests, wetlands, and water bodies have the highest supply capacities of ES, while urban and industrial areas and bare areas have a very low supply of services. On the other hand, fourteen out of twenty-nine services were selected by experts and stakeholders as the most relevant for the regions. The spatial distribution of ES has shown that the Andean Range and part of the Coastal Range have the highest ES supply capacity, mostly regulation and maintenance and cultural ES. This performance is related to the presence of native forests, water bodies, and wetlands in those zones. This study provides specific information about the most relevant ES in Biobio and Nuble according to the opinion of local stakeholders and the spatial identification of areas with a high capacity to provide services. These findings could be helpful as a reference by planners and policymakers to develop landscape management strategies oriented to preserve the supply of services in both regions.

Keywords: ecosystem services, expert judgment, mapping, multi-criteria decision making, prioritization

Procedia PDF Downloads 127

Authors: Suzanne Giasson, Alberto Guerron

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Stimuli-responsive polymer coatings can be used as functional elements in nanotechnologies, such as valves in microfluidic devices, as membranes in biomedical engineering, as substrates for the culture of biological tissues or in developing nanomaterials for targeted therapies in different diseases. However, such coatings usually suffer from major shortcomings, such as a lack of selectivity and poor environmental stability. The study will present multi-responsive hierarchical and hybrid polymer-based coatings aiming to overcome some of these limitations. Hierarchical polymer coatings, consisting of two-dimensional arrays of thermo-responsive cationic PNIPAM-based microgels and surface-functionalized with non-responsive or pH-responsive polymers, were covalently grafted to substrates to tune the surface chemistry and the elasticity of the surface independently using different stimuli. The characteristic dimensions (i.e., layer thickness) and surface properties (i.e., adhesion, friction) of the microgel coatings were assessed using the Surface Forces Apparatus. The ability to independently control the swelling and surface properties using temperature and pH as triggers were investigated for microgels in aqueous suspension and microgels immobilized on substrates. Polymer chain grafting did not impede the ability of cationic PNIPAM microgels to undergo a volume phase transition above the VPTT, either in suspension or immobilized on a substrate. Due to the presence of amino groups throughout the entirety of the microgel polymer network, the swelling behavior was also pH dependent. However, the thermo-responsive swelling was more significant than the pH-triggered one. The microgels functionalized with PEG exhibited the most promising behavior. Indeed, the thermo-triggered swelling of microgel-co-PEG did not give rise to changes in the microgel surface properties (i.e., surface potential and adhesion) within a wide range of pH values. It was possible for the immobilized microgel-co-PEG to undergo a volume transition (swelling/shrinking) with no change in adhesion, suggesting that the surface of the thermal-responsive microgels remains rather hydrophilic above the VPTT. This work confirms the possibility of tuning the swelling behavior of microgels without changing the adhesive properties. Responsive surfaces whose swelling properties can be reversibly and externally altered over space and time regardless of the surface chemistry are very innovative and will enable revolutionary advances in technologies, particularly in biomedical surface engineering and microfluidics, where advanced assembly of functional components is increasingly required.

Keywords: responsive materials, polymers, surfaces, cell culture

Procedia PDF Downloads 76

Authors: Ugo Rovigatti

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Neuroblastoma (NBL) has epitomized for at least 40 years our understanding of cancer cellular and molecular biology and its potential applications to novel therapeutic strategies. This includes the discovery of the very first oncogene aberrations and tumorigenesis suppression by differentiation in the 80s; the potential role of suppressor genes in the 90s; the relevance of immunotherapy in the millennium first, and the discovery of additional mutations by NGS technology in the millennium second decade. Similar discoveries were achieved in the majority of human cancers, and similar therapeutic interventions were obtained subsequently to NBL discoveries. Unfortunately, targeted therapies suggested by specific mutations (such as MYCN amplification –MNA- present in ¼ or 1/5 of cases) have not elicited therapeutic successes in aggressive NBL, where the prognosis is still dismal. The reasons appear to be linked to Tumor Heterogeneity, which is particularly evident in NBL but also a clear hallmark of aggressive human cancers generally. The new avenue of cancer immunotherapy (CIT) provided new hopes for cancer patients, but we still ignore the cellular or molecular targets. CIT is emblematic of high-risk disease (HR-NBL) since the mentioned GD2 passive immunotherapy is still providing better survival. We recently critically reviewed and evaluated the literature depicting the genomic landscapes of HR-NBL, coming to the qualified conclusion that among hundreds of affected genes, potential targets, or chromosomal sites, none correlated with anti-GD2 sensitivity. A better explanation is provided by the Micro-Foci inducing Virus (MFV) model, which predicts that neuroblasts infection with the MFV, an RNA virus isolated from a cancer-cluster (space-time association) of HR-NBL cases, elicits the appearance of MNA and additional genomic aberrations with mechanisms resembling chromothripsis. Neuroblasts infected with low titers of MFV amplified MYCN up to 100 folds and became highly transformed and malignant, thus causing neuroblastoma in young rat pups of strains SD and Fisher-344 and larger tumor masses in nu/nu mice. An association was discovered with GD2 since this glycosphingolipid is also the receptor for the family of MFV virus (dsRNA viruses). It is concluded that a dsRNA virus, MFV, appears to provide better explicatory mechanisms for the genesis of i) specific genomic aberrations such as MNA; ii) extensive tumor heterogeneity and chromothripsis; iii) the effects of passive immunotherapy with anti-GD2 monoclonals and that this and similar models should be further investigated in both pediatric and adult cancers.

Keywords: neuroblastoma, MYCN, amplification, viruses, GD2

Procedia PDF Downloads 100

Authors: Aleksandr Kalinenko, Igor Vysotskiy, Sergey Malopheyev, Sergey Mironov, Rustam Kaibyshev

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From a thermo-mechanical standpoint, friction-stir welding (FSW) represents a unique combination of very large strains, high temperature and relatively high strain rate. The material behavior under such extreme deformation conditions is not studied well and thus, the microstructural examinations of the friction-stir welded materials represent an essential academic interest. Moreover, a clear understanding of the microstructural mechanisms operating during FSW should improve our understanding of the microstructure-properties relationship in the FSWed materials and thus enables us to optimize their service characteristics. Despite extensive research in this field, the microstructural behavior of some important structural materials remains not completely clear. In order to contribute to this important work, the present study was undertaken to examine the grain structure evolution during the FSW of 6061-T6 aluminum alloy. To provide an in-depth insight into this process, the electron backscatter diffraction (EBSD) technique was employed for this purpose. Microstructural observations were conducted by using an FEI Quanta 450 Nova field-emission-gun scanning electron microscope equipped with TSL OIMTM software. A suitable surface finish for EBSD was obtained by electro-polishing in a solution of 25% nitric acid in methanol. A 15° criterion was employed to differentiate low-angle boundaries (LABs) from high-angle boundaries (HABs). In the entire range of the studied FSW regimes, the grain structure evolved in the stir zone was found to be dominated by nearly-equiaxed grains with a relatively high fraction of low-angle boundaries and the moderate-strength B/-B {112}<110> simple-shear texture. In all cases, the grain-structure development was found to be dictated by an extensive formation of deformation-induced boundaries, their gradual transformation to the high-angle grain boundaries. Accordingly, the grain subdivision was concluded to the key microstructural mechanism. Remarkably, a gradual suppression of this mechanism has been observed at relatively high welding temperatures. This surprising result has been attributed to the reduction of dislocation density due to the annihilation phenomena.

Keywords: electron backscatter diffraction, friction-stir welding, heat-treatable aluminum alloys, microstructure

Procedia PDF Downloads 237

Authors: Kinneret Segal

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The work of a midwife is emotionally challenging, both positively and negatively. Midwives share moments of joy when a baby is welcomed into the world, and also attend difficult events of loss and trauma. The relationship that develops with the maternity is the essence of the midwife's care, and it is a fundamental source of motivation and professional satisfaction. This close relationship with the maternity may be used as a double-edged sword in cases of exposure to traumatic events at birth. Birth problems, exposure to emergencies and traumatic events, and loss can affect the professional quality of life and the Compassion satisfaction of the midwife. It seems that the issue of traumatic experiences in the work of midwives, has not been sufficiently explored. The present study examined the associations between exposure to traumatic events, personal resilience and post-traumatic symptoms, professional quality of life and organizational commitment among midwifery nurses in Israeli hospitals. 131 midwives from three hospitals in the country's center in Israel participated in this study. The data were collected during 2021 using a self-report questionnaire that examined sociodemographic characteristics, the degree of exposure to traumatic events in the delivery room, personal resilience, post-traumatic symptoms, professional quality of life, and organizational commitment. The three most difficult traumatic events for the midwives were death or fear of death of a newborn, death or fear of the death of a mother and a quiet birth. The higher the frequency of exposure to traumatic events, the more numerous and intense the onset of post-trauma symptoms. The more numerous and powerful the post-trauma symptoms, the higher the level of professional burnout and/or compassion fatigue, and the lower the level of compassion satisfaction. High levels of compassion satisfaction and/or low professional burnout were expressed in a heightened sense of organizational commitment. Personal resilience, country of birth, traumatic symptoms and organizational commitment, predicted satisfaction from compassion. Midwives are exposed to traumatic events associated with dissatisfaction and impairment of the professional quality of life that accompanies burnout and compassion fatigue. Exposure to traumatic events leads to the appearance of traumatic symptoms, a decrease in organizational commitment, and psychological and mental well-being. The issue needs to be addressed by implementing training programs, organizational support, and policies to improving well-being and quality of care among midwives.

Keywords: traumatic experirnces, midwives, quality of life, burnout, organizational commitment, personal resilience

Procedia PDF Downloads 87

Authors: Anthony Townley

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Contract negotiation is fundamental to commercial law practice. For this study, genre and discourse analytical methodology was used to examine the legal negotiation of a Merger & Acquisition (M&A) deal undertaken by legal and business professionals in English across different jurisdictions in Europe. While some of the most delicate negotiations involved in this process were carried on face-to-face or over the telephone, these were generally progressed more systematically – and on the record – in the form of emails, email attachments, and as comments and amendments recorded in successive ‘marked-up’ versions of the contracts under negotiation. This large corpus of textual data was originally obtained by the author, in 2012, for the purpose of doctoral research. For this study, the analysis is particularly concerned with the use of emails and covering letters to exchange legal advice about the negotiations. These two genres help to stabilize and progress the negotiation process and account for negotiation activities. Swalesian analysis of functional Moves and Steps was able to identify structural similarities and differences between these text types and to identify certain salient discursive features within them. The analytical findings also indicate how particular linguistic strategies are more appropriately and more effectively associated with one legal genre rather than another. The concept of intertextuality is an important dimension of contract negotiation discourse and this study also examined how the discursive relationships between the different texts influence the way that texts are constructed. In terms of materials development, the research findings can contribute to more authentic English for Legal & Business Purposes pedagogies for students and novice lawyers and business professionals. The findings can first be used to design discursive maps that provide learners with a coherent account of the intertextual nature of the contract negotiation process. These discursive maps can then function as a framework in which to present detailed findings about the textual and structural features of the text types by applying the Swalesian genre analysis. Based on this acquired knowledge of the textual nature of contract negotiation, the authentic discourse materials can then be used to provide learners with practical opportunities to role-play negotiation activities and experience professional ways of thinking and using language in preparation for the written discourse challenges they will face in this important area of legal and business practice.

Keywords: English for legal and business purposes, discourse analysis, genre analysis, intertextuality, pedagogical materials

Procedia PDF Downloads 150

Authors: Akemi Nasu, Keiko Matsumoto

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Rehabilitation for cancer requires setting up individual goals for each patient and an approach that properly fits the stage of cancer when putting into practice. In order to cope with the daily changes in the patients' condition, the establishment of a good cooperative relationship between the nurses and the physiotherapists, occupational therapists, and speech-language-hearing therapists (therapists) becomes essential. This study will focus on the present situation of the cooperation between nurses and therapists, especially the speech-language-hearing therapists, and aim to elucidate what develops there. A semi-structured interview was conducted targeted at a physical therapist having practical experience in working in collaboration with nurses. The contents of the interview were transcribed and converted to data, and the data was encoded and categorized with sequentially increasing degrees of abstraction to conduct a qualitative explorative factor analysis of the data. When providing ethical explanations, particular care was taken to ensure that participants would not be subjected to any disadvantages as a result of participating in the study. In addition, they were also informed that their privacy would be ensured and that they have the right to decline to participate in the study. In addition, they were also informed that the results of the study would be announced publicly at an applicable nursing academic conference. This study has been approved following application to the ethical committee of the university with which the researchers are affiliated. The survey participant is a female speech-language-hearing therapist in her forties. As a result of the analysis, 6 categories were extracted consisting of 'measures to address appetite and aspiration pneumonia prevention', 'limitation of the care a therapist alone could provide', 'the all-inclusive patient- supportive care provided by nurses', 'expand the beneficial cooperation with nurses', 'providing education for nurses on the swallowing function utilizing videofluoroscopic examination of swallowing', 'enhancement of communication including conferences'. In order to improve the team performance, and for the teamwork competency necessary for the provision of safer care, mutual support is essential. As for the cooperation between nurses and therapists, this survey indicates that the maturing of the cooperation between professionals in order to improve nursing professionals' knowledge and enhance communication will lead to an improvement in the quality of the rehabilitation for cancer.

Keywords: cancer rehabilitation, nurses, speech-language-hearing therapists, interprofessional work

Procedia PDF Downloads 133

Authors: E. Nigris, F. Passalacqua

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Relating to the recent researches in the field of faculty development, this paper aims to present a pilot training programme realized at the University of Milano-Bicocca to improve teaching skills of faculty members. A total of 57 professors (both full professors and associate professors) were trained during the pilot programme in three editions of the workshop, focused on promoting skills for teaching large classes. The study takes into account: 1) the theoretical framework of the programme which combines the recent tradition about professional development and the research on in-service training of school teachers; 2) the structure and the content of the training programme, organized in a 12 hours-full immersion workshop and in individual consultations; 3) the educational specificity of the training programme which is based on the relation between 'general didactic' (active learning metholodies; didactic communication) and 'disciplinary didactics' (didactic transposition and reconstruction); 4) results about the impact of the training programme, both related to the workshop and the individual consultations. This study aims to provide insights mainly on two levels of the training program’s impact ('behaviour change' and 'transfer') and for this reason learning outcomes are evaluated by different instruments: a questionnaire filled out by all 57 participants; 12 in-depth interviews; 3 focus groups; conversation transcriptions of workshop activities. Data analysis is based on a descriptive qualitative approach and it is conducted through thematic analysis of the transcripts using analytical categories derived principally from the didactic transposition theory. The results show that the training programme developed effectively three major skills regarding different stages of the 'didactic transposition' process: a) the content selection; a more accurated selection and reduction of the 'scholarly knowledge', conforming to the first stage of the didactic transposition process; b) the consideration of students’ prior knowledge and misconceptions within the lesson design, in order to connect effectively the 'scholarly knowledge' to the 'knowledge to be taught' (second stage of the didactic transposition process); c) the way of asking questions and managing discussion in large classrooms, in line with the transformation of the 'knowledge to be taught' in 'taught knowledge' (third stage of the didactic transposition process).

Keywords: didactic communication, didactic transposition, instructional development, teaching large classroom

Procedia PDF Downloads 138

Authors: Wenya Shu, Ilinca Stanciulescu

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Carbon nanotubes (CNTs) possess attractive properties, such as high stiffness and strength, and high thermal and electrical conductivities, making them promising filler in multifunctional nanocomposites. Although CNTs can be efficient reinforcements, the expected level of mechanical performance of CNT-polymers is not often reached in practice due to the poor mechanical behavior of the CNT-polymer interfaces. It is believed that the interactions of CNT and polymer mainly result from the Van der Waals force. The interface debonding is a fracture and delamination phenomenon. Thus, the cohesive zone modeling (CZM) is deemed to give good capture of the interface behavior. The detailed, cohesive zone modeling provides an option to consider the CNT-matrix interactions, but brings difficulties in mesh generation and also leads to high computational costs. Homogenized models that smear the fibers in the ground matrix and treat the material as homogeneous are studied in many researches to simplify simulations. But based on the perfect interface assumption, the traditional homogenized model obtained by mixing rules severely overestimates the stiffness of the composite, even comparing with the result of the CZM with artificially very strong interface. A mechanical model that can take into account the interface debonding and achieve comparable accuracy to the CZM is thus essential. The present study first investigates the CNT-matrix interactions by employing cohesive zone modeling. Three different coupled CZM laws, i.e., bilinear, exponential and polynomial, are considered. These studies indicate that the shapes of the CZM constitutive laws chosen do not influence significantly the simulations of interface debonding. Assuming a bilinear traction-separation relationship, the debonding process of single CNT in the matrix is divided into three phases and described by differential equations. The analytical solutions corresponding to these phases are derived. A homogenized model is then developed by introducing a parameter characterizing interface sliding into the mixing theory. The proposed mechanical model is implemented in FEAP8.5 as a user material. The accuracy and limitations of the model are discussed through several numerical examples. The CZM simulations in this study reveal important factors in the modeling of CNT-matrix interactions. The analytical solutions and proposed homogenized model provide alternative methods to efficiently investigate the mechanical behaviors of CNT/polymer composites.

Keywords: carbon nanotube, cohesive zone modeling, homogenized model, interface debonding

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Authors: Naseem Fatima, A. N. Srivastava, Tasleem Raza, Vijay Kumar

Abstract:

Introduction: Carcinoma gallbladder is third most common gastrointestinal lethal disease with the highest incidence and mortality rate among women in Northern India. Scientists have found several risk factors that make a person more likely to develop gallbladder cancer; among these risk factors, deregulation of miRNAs has been demonstrated to be one of the most crucial factors. The changes in the expression of specific miRNA genes result in the control of inflammation, cell cycle regulation, stress response, proliferation, differentiation, apoptosis and invasion thus mediate the process in tumorgenesis. The aim of this study was to investigate the role of MiRNA-335 and may as a molecular marker in early detection of gallbladder cancer in suspected cases. Material and Methods: A total of 20 consecutive patients with gallbladder cancer aged between 30-75 years were registered for the study. Total RNA was extracted from tissue by using the mirVANA MiRNA isolation Kit according to the manufacturer’s protocol. The MiRNA- 335 and U6 snRNA-specific cDNA were reverse-transcribed from total RNA using Taqman microRNA reverse-transcription kit according to the manufacturer’s protocol. TaqMan MiRNA probes hsa-miR-335 and Taqman Master Mix without AmpEase UNG, Individual real-time PCR assays were performed in a 20 μL reaction volume on a Real-Time PCR system (Applied Biosystems StepOnePlus™) to detect MiRNA-335 expression in tissue. Relative quantification of target MiRNA expression was evaluated using the comparative cycle threshold (CT) method. The correlation was done in between cycle threshold (CT Value) of target MiRNA in gallbladder cancer with respect to non-cancerous Cholelithiasis gallbladder. Each sample was examined in triplicate. The Newman-Keuls Multiple Comparison Test was used to determine the expression of miR-335. Results: MiRNA335 was found to be significantly downregulated in the gallbladder cancer tissue (P<0.001), when compared with non-cancerous Cholelithiasis gallbladder cases. Out of 20 cases, 75% showed reduced expression of MiRNA335, were at last stage of disease with low overall survival rate and remaining 25% were showed up-regulated expression of MiRNA335 with high survival rate. Conclusion: The present study showed that reduced expression of MiRNA335 is associated with the advancement of the disease, and its deregulation may provide important clues to understanding it as a prognostic marker and opportunities for future research.

Keywords: carcinoma gallbladder, downregulation, MiRNA-335, RT-PCR assay

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