Search results for: spatial differentiation pattern

Authors: Nicole Merkle, Stefan Zander

Abstract:

Ambient Assisted Living (AAL) describes a technological and methodological stack of (e.g. formal model-theoretic semantics, rule-based reasoning and machine learning), different aspects regarding the behavior, activities and characteristics of humans. Hence, a semantic representation of the user environment and its relevant elements are required in order to allow assistive agents to recognize situations and deduce appropriate actions. Furthermore, the user and his/her characteristics (e.g. physical, cognitive, preferences) need to be represented with a high degree of expressiveness in order to allow software agents a precise evaluation of the users’ context models. The correct interpretation of these context models highly depends on temporal, spatial circumstances as well as individual user preferences. In most AAL approaches, model representations of real world situations represent the current state of a universe of discourse at a given point in time by neglecting transitions between a set of states. However, the AAL domain currently lacks sufficient approaches that contemplate on the dynamic adaptions of context-related representations. Semantic representations of relevant real-world excerpts (e.g. user activities) help cognitive, rule-based agents to reason and make decisions in order to help users in appropriate tasks and situations. Furthermore, rules and reasoning on semantic models are not sufficient for handling uncertainty and fuzzy situations. A certain situation can require different (re-)actions in order to achieve the best results with respect to the user and his/her needs. But what is the best result? To answer this question, we need to consider that every smart agent requires to achieve an objective, but this objective is mostly defined by domain experts who can also fail in their estimation of what is desired by the user and what not. Hence, a smart agent has to be able to learn from context history data and estimate or predict what is most likely in certain contexts. Furthermore, different agents with contrary objectives can cause collisions as their actions influence the user’s context and constituting conditions in unintended or uncontrolled ways. We present an approach for dynamically updating a semantic model with respect to the current user context that allows flexibility of the software agents and enhances their conformance in order to improve the user experience. The presented approach adapts rules by learning sensor evidence and user actions using probabilistic reasoning approaches, based on given expert knowledge. The semantic domain model consists basically of device-, service- and user profile representations. In this paper, we present how this semantic domain model can be used in order to compute the probability of matching rules and actions. We apply this probability estimation to compare the current domain model representation with the computed one in order to adapt the formal semantic representation. Our approach aims at minimizing the likelihood of unintended interferences in order to eliminate conflicts and unpredictable side-effects by updating pre-defined expert knowledge according to the most probable context representation. This enables agents to adapt to dynamic changes in the environment which enhances the provision of adequate assistance and affects positively the user satisfaction.

Keywords: ambient intelligence, machine learning, semantic web, software agents

Procedia PDF Downloads 260

Authors: Katarzyna Drela, Miroslaw Wielgos, Mikolaj Wrobel, Barbara Lukomska

Abstract:

Mesenchymal stem cells (MSCs) have a great potential in regenerative medicine. Since the initial number of isolated MSCs is limited, in vitro propagation is often required to reach sufficient numbers of cells for therapeutic applications. During long-term culture MSCs may undergo genetic or epigenetic alterations that subsequently increase the probability of spontaneous malignant transformation. Thus, factors that influence genomic stability of MSCs following long-term expansions need to be clarified before cultured MSCs are employed for clinical application. The aim of our study was to investigate the potential for spontaneous transformation of human neonatal cord blood (HUCB-MSCs) and adult bone marrow (BM-MSCs) derived MSCs. Materials and Methods: HUCB-MSCs and BM-MSCs were isolated by standard Ficoll gradient centrifugations method. Isolated cells were initially plated in high density 106 cells per cm2. After 48 h medium were changed and non-adherent cells were removed. The malignant transformation of MSCs in vitro was evaluated by morphological changes, proliferation rate, ability to enter cell senescence, the telomerase expression and chromosomal abnormality. Proliferation of MSCs was analyzed with WST-1 reduction method and population doubling time (PDT) was calculated at different culture stages. Then the expression pattern of genes characteristic for mesenchymal or epithelial cells, as well as transcriptions factors were examined by RT-PCR. Concomitantly, immunocytochemical analysis of gene-related proteins was employed. Results: Our studies showed that MSCs from all bone marrow isolations ultimately entered senescence and did not undergo spontaneous malignant transformation. However, HUCB-MSCs from one of the 15 donors displayed an increased proliferation rate, failed to enter senescence, and exhibited an altered cell morphology. In this sample we observed two different cell phenotypes: one mesenchymal-like exhibited spindle shaped morphology and express specific mesenchymal surface markers (CD73, CD90, CD105, CD166) with low proliferation rate, and the second one with round, densely package epithelial-like cells with significantly increased proliferation rate. The PDT of epithelial-like populations was around 1day and 100% of cells were positive for proliferation marker Ki-67. Moreover, HUCB-MSCs showed a positive expression of human telomerase reverse transcriptase (hTERT), cMYC and exhibit increased number of CFU during the long-term culture in vitro. Furthermore, karyotype analysis revealed chromosomal abnormalities including duplications. Conclusions: Our studies demonstrate that HUCB-MSCs are susceptible to spontaneous malignant transformation during long-term culture. Spontaneous malignant transformation process following in vitro culture has enormous effect on the biosafety issues of future cell-based therapies and regenerative medicine regimens.

Keywords: mesenchymal stem cells, spontaneous, transformation, long-term culture

Procedia PDF Downloads 238

Authors: Zena Tredinnick-Kirby, Anna Divinsky, Brendan Berthold, Nicole Cingolani

Abstract:

Faculty members from The Pennsylvania State University, Zena Tredinnick-Kirby, Ph.D., and Anna Divinsky are at the forefront of an innovative educational approach to improve access in asynchronous online art courses. Their pioneering work weaves virtual reality (VR) technologies to construct a more equitable educational experience for students by transforming their learning and engagement. The significance of their study lies in the need to bridge the digital divide in online art courses, making them more inclusive and interactive for all distance learners. In an era where conventional classroom settings are no longer the sole means of instruction, Tredinnick-Kirby and Divinsky harness the power of instructional technologies to break down geographical barriers by incorporating an interactive VR experience that facilitates community building within an online environment transcending physical constraints. The methodology adopted by Tredinnick-Kirby, and Divinsky is centered around integrating 3D virtual spaces into their art courses. Spatial.io, a virtual world platform, enables students to develop digital avatars and engage in virtual art museums through a free browser-based program or an Oculus headset, where they can interact with other visitors and critique each other’s artwork. The goal is not only to provide students with an engaging and immersive learning experience but also to nourish them with a more profound understanding of the language of art criticism and technology. Furthermore, the study aims to cultivate critical thinking skills among students and foster a collaborative spirit. By leveraging cutting-edge VR technology, students are encouraged to explore the possibilities of their field, experimenting with innovative tools and techniques. This approach not only enriches their learning experience but also prepares them for a dynamic and ever-evolving art landscape in technology and education. One of the fundamental objectives of Tredinnick-Kirby and Divinsky is to remodel how feedback is derived through peer-to-peer art critique. Through the inclusion of 3D virtual spaces into the curriculum, students now have the opportunity to install their final artwork in a virtual gallery space and incorporate peer feedback, enabling students to exhibit their work opening the doors to a collaborative and interactive process. Students can provide constructive suggestions, engage in discussions, and integrate peer commentary into developing their ideas and praxis. This approach not only accelerates the learning process but also promotes a sense of community and growth. In summary, the study conducted by the Penn State faculty members Zena Tredinnick-Kirby, and Anna Divinsky represents innovative use of technology in their courses. By incorporating 3D virtual spaces, they are enriching the learners' experience. Through this inventive pedagogical technique, they nurture critical thinking, collaboration, and the practical application of cutting-edge technology in art. This research holds great promise for the future of online art education, transforming it into a dynamic, inclusive, and interactive experience that transcends the confines of distance learning.

Keywords: Art, community building, distance learning, virtual reality

Procedia PDF Downloads 48

Authors: Virgilio Angelo Gelera Gener

Abstract:

This study investigates the role of short-term accommodations on the place brand and real estate development of urban areas. It aims to know the perceptions of the general public, real estate developers, as well as city and barangay-level local government units (LGUs) on how these lodgings affect the place brand and land value of a community. It likewise attempts to identify the personal and institutional variables having a great influence on said perceptions in order to provide a better understanding of these establishments and their relevance within urban localities. Using certain sources, Malate, Manila was identified to be the ideal study area of the thesis. This prompted the employment of mixed methods research as the study’s fundamental data gathering and analytical tool. Here, a survey with 350 locals was done, asking them questions that would answer the aforementioned queries. Thereafter, a Pearson Chi-square Test and Multinomial Logistic Regression (MLR) were utilized to determine the variables affecting their perceptions. There were also Focus Group Discussions (FGDs) with the three (3) most populated Malate barangays, as well as Key Informant Interviews (KIIs) with selected city officials and fifteen (15) real estate company representatives. With that, survey results showed that although a 1992 Department of Tourism (DOT) Circular regards short-term accommodations as lodgings mainly for travelers, most people actually use it for their private/intimate moments. Because of this, the survey further revealed that short-term accommodations exhibit a negative place brand among the respondents though they also believe that it’s still one of society’s most important economic players. Statistics from the Pearson Chi-square Test, on the other hand, indicate that there are fourteen (14) out of seventeen (17) variables exhibiting great influence on respondents’ perceptions. Whereas MLR findings show that being born in Malate and being part of a family household was the most significant regardless of socio-economic level and monthly household income. For the city officials, it was revealed that said lodgings are actually the second-highest earners in the City’s lodging industry. It was further stated that their zoning ordinance treats short-term accommodations just like any other lodging enterprise. So it’s perfectly legal for these establishments to situate themselves near residential areas and/or institutional structures. A sit down with barangays, on the other hand, recognized the economic benefits of short-term accommodations but likewise admitted that it contributes a negative place brand to the community. Lastly, real estate developers are amenable to having their projects built near short-term accommodations, for they do not have any bad views against it. They explained that their projects sites have always been motivated by suitability, liability, and marketability factors only. Overall, these findings merit a recalibration of the zoning ordinance and DOT Circular, as well as the imposition of regulations on their sexually suggestive roadside advertisements. Then, once relevant measures are refined for proper implementation, it can also pave the way for spatial interventions (like visual buffer corridors) to better address the needs of the locals, private groups, and government.

Keywords: estate planning, place brand, real estate development, short-term accommodations

Procedia PDF Downloads 141

Authors: Ennios Eros Giogos, Nefeli Katsarou, Giota Mantziorou, Elena Panou, Nikolaos Kourniatis, Socratis Giannoudis

Abstract:

In the context of the postgraduate course Productive Design, Department of Interior Architecture of the University of West Attica in Athens, under the guidance of Professors Nikolaos Koyrniatis and Socratis Giannoudis, kinetic mechanisms with parametric models were examined for their further application in the design of objects. In the first phase, the students studied a motion mechanism that they chose from daily experience and then analyzed its geometric structure in relation to the geometric transformations that exist. In the second phase, the students tried to design it through a parametric model in Grasshopper3d for Rhino algorithmic processor and plan the design of its application in an everyday object. For the project presented, our team began by studying the movement of living beings, specifically the snake. By studying the snake and the role that the environment has in its movement, four basic typologies were recognized: serpentine, concertina, sidewinding and rectilinear locomotion, as well as its ability to perform spiral formations. Most typologies are characterized by ripples, a series of sinusoidal curves. For the application of the snake movement in a polymorphic space divider, the use of a coil-type joint was studied. In the Grasshopper program, the simulation of the desired motion for the polymorphic surface was tested by applying a coil on a sinusoidal curve and a spiral curve. It was important throughout the process that the points corresponding to the nodes of the real object remain constant in number, as well as the distances between them and the elasticity of the construction had to be achieved through a modular movement of the coil and not some elastic element (material) at the nodes. Using mesh (repeating coil), the whole construction is transformed into a supporting body and combines functionality with aesthetics. The set of elements functions as a vertical spatial network, where each element participates in its coherence and stability. Depending on the positions of the elements in terms of the level of support, different perspectives are created in terms of the visual perception of the adjacent space. For the implementation of the model on the scale (1:3), (0.50m.x2.00m.), the load-bearing structure that was studied has aluminum rods for the basic pillars Φ6mm and Φ 2.50 mm, for the secondary columns. Filling elements and nodes are of similar material and were made of MDF surfaces. During the design process, four trapezoidal patterns were picketed, which function as filling elements, while in order to support their assembly, a different engraving facet was done. The nodes have holes that can be pierced by the rods, while their connection point with the patterns has a half-carved recess. The patterns have a corresponding recess. The nodes are of two different types depending on the column that passes through them. The patterns and knots were designed to be cut and engraved using a Laser Cutter and attached to the knots using glue. The parameters participate in the design as mechanisms that generate complex forms and structures through the repetition of constantly changing versions of the parts that compose the object.

Keywords: polymorphic, locomotion, sinusoidal curves, parametric

Procedia PDF Downloads 75

Authors: Huan Peng, Chenye Zeng, Zhao Wang

Abstract:

Alzheimer’s disease (AD) is an age-related neurodegenerative disease that is a leading cause of dementia syndromes and has become a huge burden on society and families. The main pathological features of AD involve excessive deposition of β-amyloid (Aβ) and Tau proteins in the brain, resulting in loss of neurons, expansion of neuroinflammation, and cognitive dysfunction in patients. Researchers have found effective drugs to clear the brain of error-accumulating proteins or to slow the loss of neurons, but their direct administration has key bottlenecks such as single-drug limitation, rapid blood clearance rate, impenetrable blood-brain barrier (BBB), and poor ability to target tissues and cells. Therefore, we are committed to seeking a suitable and efficient delivery system. Inspired by the possibility that exosomes may be involved in the secretion and transport mechanism of many signaling molecules or proteins in the brain, exosomes have attracted extensive attention as natural nanoscale drug carriers. We selected exosomes derived from bone marrow mesenchymal stem cells (MSC-EXO) with low immunogenicity and exosomes derived from hippocampal neurons (HT22-EXO) that may have excellent homing ability to overcome the deficiencies of oral or injectable pathways and bypass the BBB through nasal administration and evaluated their delivery ability and effect on AD. First, MSC-EXO and HT22 cells were isolated and cultured, and MSCs were identified by microimaging and flow cytometry. Then MSC-EXO and HT22-EXO were obtained by gradient centrifugation and qEV SEC separation column, and a series of physicochemical characterization were performed by transmission electron microscope, western blot, nanoparticle tracking analysis and dynamic light scattering. Next, exosomes labeled with lipophilic fluorescent dye were administered to WT mice and APP/PS1 mice to obtain fluorescence images of various organs at different times. Finally, APP/PS1 mice were administered intranasally with two exosomes 20 times over 40 days and 20 μL each time. Behavioral analysis and pathological section analysis of the hippocampus were performed after the experiment. The results showed that MSC-EXO and HT22-EXO were successfully isolated and characterized, and they had good biocompatibility. MSC-EXO showed excellent brain enrichment in APP/PS1 mice after intranasal administration, could improve the neuronal damage and reduce inflammation levels in the hippocampus of APP/PS1 mice, and the improvement effect was significantly better than HT22-EXO. However, intranasal administration of the two exosomes did not cause depression and anxious-like phenotypes in APP/PS1 mice, nor significantly improved the short-term or spatial learning and memory ability of APP/PS1 mice, and had no significant effect on the content of Aβ plaques in the hippocampus, which also meant that MSC-EXO could use their own advantages in combination with other drugs to clear Aβ plaques. The possibility of realizing highly effective non-invasive synergistic treatment for AD provides new strategies and ideas for clinical research.

Keywords: Alzheimer’s disease, exosomes derived from mesenchymal stem cell, intranasal administration, therapy-carrier dual roles

Procedia PDF Downloads 32

Authors: B. M. Vishal, Monamie Basu, Gopinath M., Rose Havilah Pulla

Abstract:

Though there are several methods of synthesizing silver nano particles, Green synthesis always has its own dignity. Ranging from the cost-effectiveness to the ease of synthesis, the process is simplified in the best possible way and is one of the most explored topics. This study of extracting secondary metabolites from Perilla frutescens and using them for therapeutic additives has its own significance. Unlike the other researches that have been done so far, this study aims to synthesize Silver nano particles from Perilla frutescens using three available forms of the plant: leaves, seed, and commercial leaf extract powder. Perilla frutescens, commonly known as 'Beefsteak Plant', is a perennial plant and belongs to the mint family. The plant has two varieties classed within itself. They are frutescens crispa and frutescens frutescens. The species, frutescens crispa (commonly known as 'Shisho' in Japanese), is generally used for edible purposes. Its leaves occur in two forms, varying on the colors. It is found in two different colors of red with purple streaks and green with crinkly pattern on it. This species is aromatic due to the presence of two major compounds: polyphenols and perillaldehyde. The red (purple streak) variety of this plant is due to the presence of a pigment, Perilla anthocyanin. The species, frutescens frutescens (commonly known as 'Egoma' in Japanese), is the main source for perilla oil. This species is also aromatic, but in this case, the major compound which gives the aroma is Perilla ketone or egoma ketone. Shisho grows short as compared with Wild Sesame and both produce seeds. The seeds of Wild Sesame are large and soft whereas that of Shisho is small and hard. The seeds have a large proportion of lipids, ranging about 38-45 percent. Excluding those, the seeds have a large quantity of Omega-3 fatty acids, linoleic acid, and an Omega-6 fatty acid. Other than these, Perilla leaf extract has gold and silver nano particles in it. The yield comparison in all the cases have been done, and the process’ optimal conditions were modified, keeping in mind the efficiencies. The characterization of secondary metabolites includes GC-MS and FTIR which can be used to identify the components of purpose that actually helps in synthesizing silver nano particles. The analysis of silver was done through a series of characterization tests that include XRD, UV-Vis, EDAX, and SEM. After the synthesis, for being used as therapeutic additives, the toxin analysis was done, and the results were tabulated. The synthesis of silver nano particles was done in a series of multiple cycles of extraction from leaves, seeds and commercially purchased leaf extract. The yield and efficiency comparison were done to bring out the best and the cheapest possible way of synthesizing silver nano particles using Perilla frutescens. The synthesized nano particles can be used in therapeutic drugs, which has a wide range of application from burn treatment to cancer treatment. This will, in turn, replace the traditional processes of synthesizing nano particles, as this method will prove effective in terms of cost and the environmental implications.

Keywords: nanoparticles, green synthesis, Perilla frutescens, characterisation, toxin analysis

Procedia PDF Downloads 206

Authors: John Doe

Abstract:

This paper presents the research project “Escape Through Culture”, which is co-funded by the European Union and national resources through the Operational Programme “Competitiveness, Entrepreneurship and Innovation” 2014-2020 and the Single RTDI State Aid Action "RESEARCH - CREATE - INNOVATE". The project implementation is assumed by three partners, (1) the Computer Technology Institute and Press "Diophantus" (CTI), experienced with the design and implementation of serious games, natural language processing and ICT in education, (2) the Laboratory of Environmental Communication and Audiovisual Documentation (LECAD), part of the University of Thessaly, Department of Architecture, which is experienced with the study of creative transformation and reframing of the urban and environmental multimodal experiences through the use of AR and VR technologies, and (3) “Apoplou”, an IT Company with experience in the implementation of interactive digital applications. The research project proposes the design of innovative infrastructure of digital educational escape games for mobile devices and computers, with the use of Virtual Reality and Augmented Reality for the promotion of Greek cultural heritage in Greece and abroad. In particular, the project advocates the combination of Greek cultural heritage and literature, digital technologies advancements and the implementation of innovative gamifying practices. The cultural experience of the players will take place in 3 layers: (1) In space: the digital games produced are going to utilize the dual character of the space as a cultural landscape (the real space - landscape but also the space - landscape as presented with the technologies of augmented reality and virtual reality). (2) In literary texts: the selected texts of Greek writers will support the sense of place and the multi-sensory involvement of the user, through the context of space-time, language and cultural characteristics. (3) In the philosophy of the "escape game" tool: whether played in a computer environment, indoors or outdoors, the spatial experience is one of the key components of escape games. The innovation of the project lies both in the junction of Augmented/Virtual Reality with the promotion of cultural points of interest, as well as in the interactive, gamified practices of literary texts. The digital escape game infrastructure will be highly interactive, integrating the projection of Greek landscape cultural elements and digital literary text analysis, supporting the creation of escape games, establishing and highlighting new playful ways of experiencing iconic cultural places, such as Elefsina, Skiathos etc. The literary texts’ content will relate to specific elements of the Greek cultural heritage depicted by prominent Greek writers and poets. The majority of the texts will originate from Greek educational content available in digital libraries and repositories developed and maintained by CTI. The escape games produced will be available for use during educational field trips, thematic tourism holidays, etc. In this paper, the methodology adopted for infrastructure development will be presented. The research is based on theories of place, gamification, gaming development, making use of corpus linguistics concepts and digital humanities practices for the compilation and the analysis of literary texts.

Keywords: escape games, cultural landscapes, gamification, digital humanities, literature

Procedia PDF Downloads 207

Authors: V. V. Fomin, A. P. Mikhailovich, E. M. Agapitov, V. E. Rogachev, E. A. Kostousova, E. S. Perekhodova

Abstract:

Ground-level landscape photos can be used as a source of objective data on woody vegetation and vegetation dynamics. We proposed a method for processing, analyzing, and presenting ground photographs, which has the following advantages: 1) researcher has to form holistic representation of the study area in form of a set of interlapping ground-level landscape photographs; 2) it is necessary to define or obtain characteristics of the landscape, objects, and phenomena present on the photographs; 3) it is necessary to create new or supplement existing textual descriptions and annotations for the ground-level landscape photographs; 4) single or multiple ground-level landscape photographs can be used to develop specialized geoinformation layers, schematic maps or thematic maps; 5) it is necessary to determine quantitative data that describes both images as a whole, and displayed objects and phenomena, using algorithms for automated image analysis. It is suggested to match each photo with a polygonal geoinformation layer, which is a sector consisting of areas corresponding with parts of the landscape visible in the photos. Calculation of visibility areas is performed in a geoinformation system within a sector using a digital model of a study area relief and visibility analysis functions. Superposition of the visibility sectors corresponding with various camera viewpoints allows matching landscape photos with each other to create a complete and wholesome representation of the space in question. It is suggested to user-defined data or phenomenons on the images with the following superposition over the visibility sector in the form of map symbols. The technology of geoinformation layers’ spatial superposition over the visibility sector creates opportunities for image geotagging using quantitative data obtained from raster or vector layers within the sector with the ability to generate annotations in natural language. The proposed method has proven itself well for relatively open and clearly visible areas with well-defined relief, for example, in mountainous areas in the treeline ecotone. When the polygonal layers of visibility sectors for a large number of different points of photography are topologically superimposed, a layer of visibility of sections of the entire study area is formed, which is displayed in the photographs. Also, as a result of this overlapping of sectors, areas that did not appear in the photo will be assessed as gaps. According to the results of this procedure, it becomes possible to obtain information about the photos that display a specific area and from which points of photography it is visible. This information may be obtained either as a query on the map or as a query for the attribute table of the layer. The method was tested using repeated photos taken from forty camera viewpoints located on Ray-Iz mountain massif (Polar Urals, Russia) from 1960 until 2023. It has been successfully used in combination with other ground-based and remote sensing methods of studying the climate-driven dynamics of woody vegetation in the Polar Urals. Acknowledgment: This research was collaboratively funded by the Russian Ministry for Science and Education project No. FEUG-2023-0002 (image representation) and Russian Science Foundation project No. 24-24-00235 (automated textual description).

Keywords: woody, vegetation, repeated, photographs

Procedia PDF Downloads 30

Authors: M. Eickermann, F. Ronellenfitsch, J. Junk

Abstract:

Oilseed rape (Brassica napus L.) is one of the most important crops throughout Europe, but pressure due to pest insects and pathogens can reduce yield amount substantially. Therefore, the usage of pesticide applications is outstanding in this crop. In addition, climate change effects can interact with phenology of the host plant and their pests and can apply additional pressure on the yield. Next to the pollen beetle, Meligethes aeneus L., the seed-damaging pest insects, cabbage seed weevil (Ceutorhynchus obstrictus Marsham) and the brassica pod midge (Dasineura brassicae Winn.) are of main economic impact to the yield. While females of C. obstrictus are infesting oilseed rape by depositing single eggs into young pods, the females of D. brassicae are using this local damage in the pod for their own oviposition, while depositing batches of 20-30 eggs. Without a former infestation by the cabbage seed weevil, a significant yield reduction by the brassica pod midge can be denied. Based on long-term, multisided field experiments, a comprehensive data-set on pest migration to crops of B. napus has been built up in the last ten years. Five observational test sides, situated in different climatic regions in Luxembourg were controlled between February until the end of May twice a week. Pest migration was recorded by using yellow water pan-traps. Caught insects were identified in the laboratory according to species specific identification keys. By a combination of pest observations and corresponding meteorological observations, the set-up of models to predict the migration periods of the seed-damaging pests was possible. This approach is the basis for a computer-based decision support tool, to assist the farmer in identifying the appropriate time point of pesticide application. In addition, the derived algorithms of that decision support tool can be combined with climate change projections in order to assess the future potential threat caused by the seed-damaging pest species. Regional climate change effects for Luxembourg have been intensively studied in recent years. Significant changes to wetter winters and drier summers, as well as a prolongation of the vegetation period mainly caused by higher spring temperature, have also been reported. We used the COSMO-CLM model to perform a time slice experiment for Luxembourg with a spatial resolution of 1.3 km. Three ten year time slices were calculated: The reference time span (1991-2000), the near (2041-2050) and the far future (2091-2100). Our results projected a significant shift of pest migration to an earlier onset of the year. In addition, a prolongation of the possible migration period could be observed. Because D. brassiace is depending on the former oviposition activity by C. obstrictus to infest its host plant successfully, the future dependencies of both pest species will be assessed. Based on this approach the future risk potential of both seed-damaging pests is calculated and the status as pest species is characterized.

Keywords: CORDEX projections, decision support tool, Brassica napus, pests

Procedia PDF Downloads 353

Authors: Samia Elfekih, Wee Tek Tay, Karl Gordon, Paul De Barro

Abstract:

Invasive species represent an increasing threat to food biosecurity, causing significant economic losses in agricultural systems. An example is the sweet potato whitefly, Bemisia tabaci, which is a complex of morphologically indistinguishable species causing average annual global damage estimated at US$2.4 billion. The Bemisia complex represents an interesting model for evolutionary studies because of their extensive distribution and potential for invasiveness and population expansion. Within this complex, two species, Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) have invaded well beyond their home ranges whereas others, such as Indian Ocean (IO) and Australia (AUS), have not. In order to understand why some Bemisia species have become invasive, genome-wide sequence scans were used to estimate population dynamics over time and relate these to climate. The Bayesian Skyline Plot (BSP) method as implemented in BEAST was used to infer the historical effective population size. In order to overcome sampling bias, the populations were combined based on geographical origin. The datasets used for this particular analysis are genome-wide SNPs (single nucleotide polymorphisms) called separately in each of the following groups: Sub-Saharan Africa (Burkina Faso), Europe (Spain, France, Greece and Croatia), USA (Arizona), Mediterranean-Middle East (Israel, Italy), Middle East-Central Asia (Turkmenistan, Iran) and Reunion Island. The non-invasive ‘AUS’ species endemic to Australia was used as an outgroup. The main findings of this study show that the BSP for the Sub-Saharan African MED population is different from that observed in MED populations from the Mediterranean Basin, suggesting evolution under a different set of environmental conditions. For MED, the effective size of the African (Burkina Faso) population showed a rapid expansion ≈250,000-310,000 years ago (YA), preceded by a period of slower growth. The European MED populations (i.e., Spain, France, Croatia, and Greece) showed a single burst of expansion at ≈160,000-200,000 YA. The MEAM1 populations from Israel and Italy and the ones from Iran and Turkmenistan are similar as they both show the earlier expansion at ≈250,000-300,000 YA. The single IO population lacked the latter expansion but had the earlier one. This pattern is shared with the Sub-Saharan African (Burkina Faso) MED, suggesting IO also faced a similar history of environmental change, which seems plausible given their relatively close geographical distributions. In conclusion, populations within the invasive species MED and MEAM1 exhibited signatures of population expansion lacking in non-invasive species (IO and AUS) during the Pleistocene, a geological epoch marked by repeated climatic oscillations with cycles of glacial and interglacial periods. These expansions strongly suggested the potential of some Bemisia species’ genomes to affect their adaptability and invasiveness.

Keywords: whitefly, RADseq, invasive species, SNP, climate change

Procedia PDF Downloads 107

Authors: Manushi Srivastava

Abstract:

Introduction: Doctor’s role, and relation with respect to patient care is at the core of medical ethics. The rapid pace of medical advances along with increasing consumer awareness about their rights and hike in cost of effective health care demand a robust, transparent and patient-friendly medical care system. However, doctors’ role performance is still in the frame of activity-passivity model of Doctor-Patient Relationship (DPR) where doctors act as parent and use to instruct their patients, without their consensus that is not going to help in the 21st century. Thus the current situation is a new challenge for traditional doctor-patient relationship after the introduction of Consumer Protection Act (CPA) in medical profession and the same is evidenced by increasing cases of medical litigation. To strengthen this system of medical services, the doctor plays a vital role, and the same should be reviewed in the present context. Objective: To understand the opinion of consultants regarding medical negligence and effect of Consumer Protection Act in terms of current practices of patient care. Method: This is a cross-sectional study in which both quantitative and qualitative methods are applied. Total 69 consultants were selected from multi-specialty hospitals of densely populated Varanasi city catering a population of about 1.8 million. Two-stage sampling was used for selection of respondents. At the first stage, selection of major wards (Medicine, Surgery, Ophthalmology, Gynaecology, Orthopaedics, and Paediatrics) was carried out, which are more susceptible to medical negligence. At the second stage, selection of consultants from the respective wards was carried out. In-depth Interviews were conducted with the help of semi-structured schedule. Two case studies of medical negligence were also carried out as part of the qualitative study. Analysis: Data were analyzed with the help of SPSS software (21.0 trial version). Semi-structured research tool was used to know consultant’s opinion about the pattern of medical negligence cases, litigations and claims made by patient community and inclusion of government medical services in CPA. Statistical analysis was done to describe data, and non-parametric test was used to observe the association between the variables. Analysis of Verbatim was used in case-study. Findings and Conclusion: Majority (92.8%) of consultants felt changes in the behaviour of community (patient) after implementation of CPA, as it had increased awareness about their rights. Less than half of the consultants opined that Medical Negligence is an Unintentional act of doctors and generally occurs due to communication gap and behavioural problem between doctor and patients. Experienced consultants ( > 10 years) pointed out that unethical practice by doctors and mal-intention of patient to harass doctors were additional reasons of Medical Negligence. In-depth interview revealed that now patients’ community expects more transparency and hence they demand cafeteria approach in diagnosis and management of cases. Thus as study results, we propose ‘Agreement Model’ of DPR to re-ensure ethical practice in medical profession.

Keywords: doctors, communication, consumer protection act (CPA), medical error

Procedia PDF Downloads 143

Authors: Inês Amorim Leitão, Loes van Shaick, António Dinis Ferreira, Violette Geissen

Abstract:

Plastic pollution is a growing concern worldwide: plastics are commercialized in large quantities and it takes a long time for them to degrade. When in the environment, plastic is fragmented into microplastics (<5mm), which have been found in all environmental compartments at different locations. Microplastics contribute to the environmental pollution in water, air and soil and are linked to human health problems. The progressive increase of population living in cities led to the aggravation of the pollution problem worldwide, especially in urban environments. Urban areas represent a strong source of pollution, through the roads, industrial production, wastewater, landfills, etc. It is expected that pollutants such as microplastics are transported diffusely from the sources through different pathways such as wind and rain. Therefore, it is very complex to quantify, control and treat these pollutants, designated current problematic issues by the European Commission. Green areas are pointed out by experts as natural filters for contaminants in cities, through their capacity of retention by vegetation. These spaces have thus the capacity to control the load of pollutants transported. This study investigates the spatial distribution of microplastics in urban soils of different land uses, their transport through atmospheric deposition, wind erosion, runoff and streams, as well as their deposition in vegetation like grass and tree leaves in urban environment. Coimbra, a medium large city located in the central Portugal, is the case-study. All the soil, sediments, water and vegetation samples were collected in Coimbra and were later analyzed in the Wageningen University & Research laboratory. Microplastics were extracted through the density separation using Sodium Phosphate as solution (~1.4 g cm−3) and filtration methods, visualized under a stereo microscope and identified using the u-FTIR method. Microplastic particles were found in all the different samples. In terms of soils, higher concentrations of microplastics were found in green parks, followed by landfills and industrial places, and the lowest concentrations in forests and pasture land-uses. Atmospheric deposition and streams after rainfall events seems to represent the strongest pathways of microplastics. Tree leaves can retain microplastics on their surfaces. Small leaves such as needle leaves seem to present higher amounts of microplastics per leaf area than bigger leaves. Rainfall episodes seem to reduce the concentration of microplastics on leaves surface, which suggests the wash of microplastics down to lower levels of the tree or to the soil. When in soil, different types of microplastics could be transported to the atmosphere through wind erosion. Grass seems to present high concentrations of microplastics, and the enlargement of the grass cover leads to a reduction of the amount of microplastics in soil, but also of the microplastics moved from the ground to the atmosphere by wind erosion. This study proof that vegetation can help to control the transport and dispersion of microplastics. In order to control the entry and the concentration of microplastics in the environment, especially in cities, it is essential to defining and evaluating nature-based land-use scenarios, considering the role of green urban areas in filtering small particles.

Keywords: microplastics, cities, sources, pathways, vegetation

Procedia PDF Downloads 29

Authors: Kristina Horvat Blazinovic

Abstract:

In the context of a work of art, one can talk about the idea-concept-term-intention expressed by the artist by using various forms of repetition (external, material, visible repetition). Such repetitions of elements (images in space or moving visual and sound images in time) suggest a "covert", "latent" ("dressed") repetition – i.e., "hidden", "latent" term-intention-idea. Repeating in this way reveals a "deeper truth" that the viewer needs to decode and which is hidden "under" the technical manifestation of the multiplied images. It is not only images, sounds, and screens that are repeated - something else is repeated through them as well, even if, in some cases, the very idea of repetition is repeated. This paper examines serial images and single-channel or multi-channel artwork in the field of video/film art and video installations, which in a way implies the concept of repetition and multiplication. Moving or static images and screens (as multi-screens) are repeated in time and space. The categories of the real and the symbolic partly refer to the Lacan registers of reality, i.e., the Imaginary - Symbolic – Real trinity that represents the orders within which human subjectivity is established. Authors such as Bruce Nauman, VALIE EXPORT, Ragnar Kjartansson, Wolf Vostell, Shirin Neshat, Paul Sharits, Harun Farocki, Dalibor Martinis, Andy Warhol, Douglas Gordon, Bill Viola, Frank Gillette, and Ira Schneider, and Marina Abramovic problematize, in different ways, the concept and procedures of multiplication - repetition, but not in the sense of "copying" and "repetition" of reality or the original, but of repeated repetitions of the simulacrum. Referential works of art are often connected by the theme of the traumatic. Repetitions of images and situations are a response to the traumatic (experience) - repetition itself is a symptom of trauma. On the other hand, repeating and multiplying traumatic images results in a new traumatic effect or cancels it. Reflections on repetition as a temporal and spatial phenomenon are in line with the chapters that link philosophical considerations of space and time and experience temporality with their manifestation in works of art. The observations about time and the relation of perception and memory are according to Henry Bergson and his conception of duration (durée) as "quality of quantity." The video works intended to be displayed as a video loop, express the idea of infinite duration ("pure time," according to Bergson). The Loop wants to be always present - to fixate in time. Wholeness is unrecognizable because the intention is to make the effect infinitely cyclic. Reflections on time and space end with considerations about the occurrence and effects of time and space intervals as places and moments "between" – the points of connection and separation, of continuity and stopping - by reference to the "interval theory" of Soviet filmmaker DzigaVertov. The scale of opportunities that can be explored in interval mode is wide. Intervals represent the perception of time and space in the form of pauses, interruptions, breaks (e.g., emotional, dramatic, or rhythmic) denote emptiness or silence, distance, proximity, interstitial space, or a gap between various states.

Keywords: video installation, performance, repetition, multi-screen, real and symbolic, loop, video art, interval, video time

Procedia PDF Downloads 149

Authors: Ana Pinheiro, Fatima Suleman

Abstract:

Literature has revealed strong awareness of companies in regard of expatriation, but issues associated with repatriation of employees after an international assignment have been overlooked. Repatriation is one of the most challenging human resource practices that affect how companies benefit from acquired skills and high potential employees; and gain competitive advantage through network developed during expatriation. However, empirical evidence achieved so far suggests that expatriates have been disappointed because companies lack an effective repatriation strategy. Repatriates’ professional and emotional needs are often unrecognized, while repatriation is perceived as a non-issue by companies. The underlying assumption is that the return to parent company, and original country, culture and language does not demand for any particular support. Unfortunately, this basic view has non-negligible consequences on repatriates, especially on expatriate retention and turnover rates after expatriation. The goal of our study is to examine the specific policies and practices adopted by companies to support employees after an international assignment. We assume that expatriation is process which ends with repatriation. The latter is such a crucial issue as the expatriation and require due attention through appropriate design of human resource management policies and tools. For this purpose, we use data from a qualitative research based on interviews to a sample of firms operating in Portugal. We attempt to compare how firms accommodate the concerns with repatriation in their policies and practices. Therefore, the interviews collect data on both expatriation and repatriation process, namely the selection and skills of candidates to expatriation, training, mentoring, communication and pay policies. Portuguese labor market seems to be an interesting case study for mainly two reasons. On the one hand, Portuguese Government is encouraging companies to internationalize in the context of an external market-oriented growth model. On the other hand, expatriation is being perceived as a job opportunity in the context of high unemployment rates of both skilled and non-skilled. This is an ongoing research and the data collected until now indicate that companies follow the pattern described in the literature. The interviewed companies recognize the higher relevance of repatriation process than expatriation, but disregard specific human resource policies. They have perceived that unfavorable labor market conditions discourage mobility across companies. It should be stressed that companies underline that employees enhanced the relevance of stable jobs and attach far less importance to career development and other benefits after expatriation. However, there are still cases of turnover and difficulties of retention. Managers’ report non-negligible cases of turnover associated with lack of effective repatriation programs and non-recognition of good performance. Repatriates seem to having acquired entrepreneurial spirit and skills and often create their own company. These results suggest that even in the context of worsening labor market conditions, there should be greater awareness of the need to retain talents, experienced and highly skills employees. Ultimately, other companies poach invaluable assets, while internationalized companies risk being training providers.

Keywords: expatriates, expatriation, international management, repatriation

Procedia PDF Downloads 314

Authors: Ali Kazemi

Abstract:

The digital evolution of financial services, while offering unprecedented convenience and accessibility, has also escalated the vulnerabilities to fraudulent activities. In this study, we introduce a distinct approach to real-time anomaly detection in financial transactions, aiming to fortify the defenses of banking and financial institutions against such threats. Utilizing unsupervised machine learning algorithms, specifically autoencoders and isolation forests, our research focuses on identifying irregular patterns indicative of fraud within transactional data, thus enabling immediate action to prevent financial loss. The data we used in this study included the monetary value of each transaction. This is a crucial feature as fraudulent transactions may have distributions of different amounts than legitimate ones, such as timestamps indicating when transactions occurred. Analyzing transactions' temporal patterns can reveal anomalies (e.g., unusual activity in the middle of the night). Also, the sector or category of the merchant where the transaction occurred, such as retail, groceries, online services, etc. Specific categories may be more prone to fraud. Moreover, the type of payment used (e.g., credit, debit, online payment systems). Different payment methods have varying risk levels associated with fraud. This dataset, anonymized to ensure privacy, reflects a wide array of transactions typical of a global banking institution, ranging from small-scale retail purchases to large wire transfers, embodying the diverse nature of potentially fraudulent activities. By engineering features that capture the essence of transactions, including normalized amounts and encoded categorical variables, we tailor our data to enhance model sensitivity to anomalies. The autoencoder model leverages its reconstruction error mechanism to flag transactions that deviate significantly from the learned normal pattern, while the isolation forest identifies anomalies based on their susceptibility to isolation from the dataset's majority. Our experimental results, validated through techniques such as k-fold cross-validation, are evaluated using precision, recall, and the F1 score alongside the area under the receiver operating characteristic (ROC) curve. Our models achieved an F1 score of 0.85 and a ROC AUC of 0.93, indicating high accuracy in detecting fraudulent transactions without excessive false positives. This study contributes to the academic discourse on financial fraud detection and provides a practical framework for banking institutions seeking to implement real-time anomaly detection systems. By demonstrating the effectiveness of unsupervised learning techniques in a real-world context, our research offers a pathway to significantly reduce the incidence of financial fraud, thereby enhancing the security and trustworthiness of digital financial services.

Keywords: anomaly detection, financial fraud, machine learning, autoencoders, isolation forest, transactional data analysis

Procedia PDF Downloads 32

Authors: Gianmarco Taveri, Ivo Dlouhy

Abstract:

Geopolymers are well-suited materials to abate CO2 emission coming from the Portland cement production, and then replace them, in the near future, in building and other applications. The cost of production of geopolymers may be seen the only weakness, but the use of wastes as raw materials could provide a valid solution to this problem, as demonstrated by the successful incorporation of fly-ash, a by-product of thermal power plants, and waste glasses. Recycled glass in waste-derived geopolymers was lately employed as a further silica source. In this work we present, for the first time, the introduction of recycled borosilicate glass (BSG). BSG is actually a waste glass, since it derives from dismantled pharmaceutical vials and cannot be reused in the manufacturing of the original articles. Owing to the specific chemical composition (BSG is an ‘alumino-boro-silicate’), it was conceived to provide the key components of zeolitic networks, such as amorphous silica and alumina, as well as boria (B2O3), which may replace Al2O3 and contribute to the polycondensation process. The solid–state MAS NMR spectroscopy was used to assess the extent of boron oxide incorporation in the structure of geopolymers, and to define the degree of networking. FTIR spectroscopy was utilized to define the degree of polymerization and to detect boron bond vibration into the structure. Mechanical performance was tested by means of 3 point bending (flexural strength), chevron notch test (fracture toughness), compression test (compressive strength), micro-indentation test (Vicker’s hardness). Spectroscopy (SEM and Confocal spectroscopy) was performed on the specimens conducted to failure. FTIR showed a characteristic absorption band attributed to the stretching modes of tetrahedral boron ions, whose tetrahedral configuration is compatible to the reaction product of geopolymerization. 27Al NMR and 29Si NMR spectra were instrumental in understanding the extent of the reaction. 11B NMR spectroscopies evidenced a change of the trigonal boron (BO3) inside the BSG in favor of a quasi-total tetrahedral boron configuration (BO4). Thanks to these results, it was inferred that boron is part of the geopolymeric structure, replacing the Si in the network, similarly to the aluminum, and therefore improving the quality of the microstructure, in favor of a more cross-linked network. As expected, the material gained as much as 25% in compressive strength (45 MPa) compared to the literature, whereas no improvements were detected in flexural strength (~ 5 MPa) and superficial hardness (~ 78 HV). The material also exhibited a low fracture toughness (0.35 MPa*m1/2), with a tangible brittleness. SEM micrographies corroborated this behavior, showing a ragged surface, along with several cracks, due to the high presence of porosity and impurities, acting as preferential points for crack initiation. The 3D pattern of the surface fracture, following the confocal spectroscopy, evidenced an irregular crack propagation, whose proclivity was mainly, but not always, to follow the porosity. Hence, the crack initiation and propagation are largely unpredictable.

Keywords: borosilicate glass, characterization, fly-ash, geopolymerization

Procedia PDF Downloads 183

Authors: Iliuta Cumpanasu, Veronica Oana Cumpanasu

Abstract:

This paper focuses on studying the conjunction between the new emerged theory of “Memory Effect” in Irregular Migration and Related Criminality and the notion of securitization, and its impact on border management, bringing about a scientific advancement in the field by identifying the patterns corresponding to the linkage of the two concepts, for the first time, and developing a theoretical explanation, with respect to the effects of the non-military threats on border security. Over recent years, irregular migration has experienced a significant increase worldwide. The U.N.'s refugee agency reports that the number of displaced people is at its highest ever - surpassing even post-World War II numbers when the world was struggling to come to terms with the most devastating event in history. This is also the fresh reality within the core studied coordinate, the Balkan Route of Irregular Migration, which starts from Asia and Africa and continues to Turkey, Greece, North Macedonia or Bulgaria, Serbia, and ends in Romania, where thousands of migrants find themselves in an irregular situation concerning their entry to the European Union, with its important consequences concerning the related criminality. The data from the past six years was collected by making use of semi-structured interviews with experts in the field of migration and desk research within some organisations involved in border security, pursuing the gathering of genuine insights from the aforementioned field, which was constantly addressed the existing literature and subsequently subjected to the mixed methods of analysis, including the use of the Vector Auto-Regression estimates model. Thereafter, the analysis of the data followed the processes and outcomes in Grounded Theory, and a new Substantive Theory emerged, explaining how the phenomena of irregular migration and cross-border criminality are the decisive impetus for implementing the concept of securitization in border management by using the proposed pattern. The findings of the study are therefore able to capture an area that has not yet benefitted from a comprehensive approach in the scientific community, such as the seasonality, stationarity, dynamics, predictions, or the pull and push factors in Irregular Migration, also highlighting how the recent ‘Pandemic’ interfered with border security. Therefore, the research uses an inductive revelatory theoretical approach which aims at offering a new theory in order to explain a phenomenon, triggering a practically handy contribution for the scientific community, research institutes or Academia and also usefulness to organizational practitioners in the field, among which UN, IOM, UNHCR, Frontex, Interpol, Europol, or national agencies specialized in border security. The scientific outcomes of this study were validated on June 30, 2021, when the author defended his dissertation for the European Joint Master’s in Strategic Border Management, a two years prestigious program supported by the European Commission and Frontex Agency and a Consortium of six European Universities and is currently one of the research objectives of his pending PhD research at the West University Timisoara.

Keywords: migration, border, security, memory effect

Procedia PDF Downloads 61

Authors: Manju Bala Jassi

Abstract:

The Covid 19 pandemic has badly mauled Dubai’s GDP heavily dependent on hospitality, tourism, entertainment, logistics, property and the retail sectors. In the context of the World Health protocols on social distancing for better maintenance of health and hygiene, the revival of the battered tourism and hospitality sectors has serious lessons for designers- interiors and public places. The tangible and intangible aesthetic elements and design –ambiance, materials, furnishings, colors, lighting and interior with architectural design issues of tourism and hospitality need a rethink to ensure a memorable tourist experience. Designers ought to experiment with sustainable places of tourism and design, develop, build and projects are aesthetic and leave as little negative impacts on the environment and public as possible. In short, they ought to conceive public spaces that makes use of little untouched materials and energy, and creates pollution and waste that are minimal. The spaces can employ healthier and more resource-efficient prototypes of construction, renovation, operation, maintenance, and demolition and thereby mitigate the environment impacts of the construction activities and it is sustainable These measures encompass the hospitality sector that includes hotels and restaurants which has taken the hardest fall from the pandemic. The paper sought to examine building energy efficiency and materials and design employed in public places, green buildings to achieve constructive sustainability and to establish the benefits of utilizing energy efficiency, green materials and sustainable design; to document diverse policy interventions, design and Spatial dimensions of tourism and hospitality sectors; to examine changes in the hospitality, aviation sector especially from a design perspective regarding infrastructure or operational constraints and additional risk-mitigation measures; to dilate on the nature of implications for interior designers and architects to design public places to facilitate sustainable tourism and hospitality while balancing convenient space and their operations' natural surroundings. The qualitative research approach was adopted for the study. The researcher collected and analyzed data in continuous iteration. Secondary data was collected from articles in journals, trade publications, government reports, newspaper/ magazine articles, policy documents etc. In depth interviews were conducted with diverse stakeholders. Preliminary data indicates that designers have started imagining public places of tourism and hospitality against the backdrop of the government push and WHO guidelines. For instance, with regard to health, safety, hygiene and sanitation, Emirates, the Dubai-based airline has augmented health measures at the Dubai International Airport and on board its aircraft. It has leveraged high tech/ Nano-tech, social distancing to encourage least human contact, flexible design layouts to limit the occupancy. The researcher organized the data into thematic categories and found that the Government of Dubai has initiated comprehensive measures in the hospitality, tourism and aviation sectors in compliance with the WHO guidelines.

Keywords: Covid 19, design, Dubai, hospitality, public spaces, tourism

Procedia PDF Downloads 139

Authors: Babak Forouraghi

Abstract:

A genetic circuit is a collection of interacting genes and proteins that enable individual cells to implement and perform vital biological functions such as cell division, growth, death, and signaling. In cell engineering, synthetic gene circuits are engineered networks of genes specifically designed to implement functionalities that are not evolved by nature. These engineered networks enable scientists to tackle complex problems such as engineering cells to produce therapeutics within the patient's body, altering T cells to target cancer-related antigens for treatment, improving antibody production using engineered cells, tissue engineering, and production of genetically modified plants and livestock. Construction of computational models to realize genetic circuits is an especially challenging task since it requires the discovery of flow of genetic information in complex biological systems. Building synthetic biological models is also a time-consuming process with relatively low prediction accuracy for highly complex genetic circuits. The primary goal of this study was to investigate the utility of a pre-trained bidirectional encoder transformer that can accurately predict gene expressions in genetic circuit designs. The main reason behind using transformers is their innate ability (attention mechanism) to take account of the semantic context present in long DNA chains that are heavily dependent on spatial representation of their constituent genes. Previous approaches to gene circuit design, such as CNN and RNN architectures, are unable to capture semantic dependencies in long contexts as required in most real-world applications of synthetic biology. For instance, RNN models (LSTM, GRU), although able to learn long-term dependencies, greatly suffer from vanishing gradient and low-efficiency problem when they sequentially process past states and compresses contextual information into a bottleneck with long input sequences. In other words, these architectures are not equipped with the necessary attention mechanisms to follow a long chain of genes with thousands of tokens. To address the above-mentioned limitations of previous approaches, a transformer model was built in this work as a variation to the existing DNA Bidirectional Encoder Representations from Transformers (DNABERT) model. It is shown that the proposed transformer is capable of capturing contextual information from long input sequences with attention mechanism. In a previous work on genetic circuit design, the traditional approaches to classification and regression, such as Random Forrest, Support Vector Machine, and Artificial Neural Networks, were able to achieve reasonably high R2 accuracy levels of 0.95 to 0.97. However, the transformer model utilized in this work with its attention-based mechanism, was able to achieve a perfect accuracy level of 100%. Further, it is demonstrated that the efficiency of the transformer-based gene expression classifier is not dependent on presence of large amounts of training examples, which may be difficult to compile in many real-world gene circuit designs.

Keywords: transformers, generative ai, gene expression design, classification

Procedia PDF Downloads 38

Authors: Alex Konrad

Abstract:

In 2017, about 4.5 million Muslims live in Germany. They can practice their faith openly, mostly in well-equipped community centers. At the same time, right-wing politicians and media allege that all Muslims tend to be radical and undemocratic. Both perspectives are rooted in an interacting development since the 1970s. German authorities closed the 'King Fahd Academy' international school in Bonn in summer 2017 because they accused the school administration of attracting Islamists. Only 30 years ago, German authorities and labor unions directed their requests for pastoral care of the Muslim communities in Germany to the Turkish and Saudi administrations. This study shows the leading and misleading tracks of Muslim life and its perception in Germany from a historical point of view. Most of the Muslims came as so-called 'Gastarbeiter' (migrant workers) from Turkey and Morocco to West Germany in the 1960s and 1970s. Until the late 1970s, German society recognized them as workforce solely and ignored their religious needs broadly. The Iranian Revolution of 1979 caused widespread hysteria about Islamic radicalization. Likewise, it shifted the German perception of migrant workers in Germany. For the first time, the majority society saw them as religious people. Media and self-proclaimed 'experts' on Islam suspected Muslims in Germany of subversive and undemocratic belief. On the upside, they obtained the opportunity to be heard by German society and authorities. In the ensuing decades, Muslims and Islamophiles fought a discursive struggle against right-wing politicians, 'experts' and media with monolithic views. In the 1990s, Muslims achieved to establish a solid infrastructure of Islamic community center throughout Germany. Their religious life became present and contributed to diversifying the common monolithic images of Muslims as insane fundamentalists in Germany. However, the media and many 'experts' promoted the fundamentalist narrative, which gained more and more acceptance in German society at the same time. This study uses archival sources from German authorities, Islamic communities, together with local and national media to get a close approach to the contemporary historical debates. In addition, contributions by Muslims and Islamophiles in Germany, for example in magazines, event reports, and internal communication, revealing their quotidian struggle for more acceptance are being used as sources. The inclusion of widely publicized books, documentaries and newspaper articles about Islam as a menace to Europe conduces to a balanced analysis of the contemporary debates and views. Theoretically, the study applies the Third Space approach. Muslims in Germany fight the othering by the German majority society. It was their chief purpose not to be marginalized in both spatial meanings, discursively and physically. Therefore, they established realities of life as hybrids in Germany. This study reconstructs the development of the perception of Muslims in Germany. It claims that self-proclaimed experts and politicians with monolithic views maintained the hegemonic discursive positions and coined the German images of Muslims. Nevertheless, Muslims in Germany accomplished that Muslim presence in Germany’s everyday life became an integral part of society and the public sphere. This is how Muslims hybridized religious spaces in Germany.

Keywords: experts, fundamentalism, Germany, hybridization, Islamophobia, migrant workers

Procedia PDF Downloads 202

Authors: Teresa Wanjiru Mbatia

Abstract:

On 7th June 2011, the government Minister of Roads in Kenya announced the proposed construction of a major highway known as a southern bypass to run on the northern border of the Nairobi National Park. The following day on 8th June 2011, the chairperson of the Friends of Nairobi National Park (FONNAP) posted a protest statement on their website, with the heading, ‘Nairobi Park is Not a cake’ alerting its members and conservation groups, with the aim of getting support to the campaign against the government’s intention to hive off a section of the park for road construction. This was the first and earliest statement that led to a series of other events that culminated in conservationists and some other members of the public campaign against the government’s plan to hive off sections of the park to build road and railway infrastructure in or around the park. Together with other non-state actors, mostly non-governmental organisations in conservation/environment and tourism businesses, FoNNAP issued a series of other statements on social, print and electronic media to battle against road and railway construction. This paper examined the strategies, outcomes and interests of actors involved in opposing/proposing the development of transport infrastructure in and around the Nairobi National Park. Specifically, the objectives were to analyse the: (1) Arguments put forward by the eco-warriors to protest infrastructure development; (2) Background and interests of the eco-warriors; (3) Needs/interests and opinions of ordinary common citizens on transport infrastructural development, particularly in and around the urban nature reserve and (4) Final outcomes of the eco-politics surrounding infrastructure development in and around Nairobi National Park. The methodological approach used was environmental history and the social construction of nature. The study collected combined qualitative data using four main approaches, the grounded theory approach, narratives, case studies and a phenomenological approach. The information collected was analysed using critical discourse analysis. The major findings of the study were that under the guise of “public participation,” influential non-state actors have the capacity to perpetuate social-spatial inequalities in the form of curtailing the majority from accessing common public goods. A case in point in this study is how the efforts of powerful conservationists, environmentalists, and tourism businesspersons managed to stall the construction of much-needed road and railway infrastructure severally through litigations in lengthy environmental court processes involving injunctions and stop orders to the government bodies in charge. Moreover, powerful non-state actors were found to have formed informal and sometimes formal coalitions with politicians with selfish interests, which serves to deepen the exclusionary practices and the common good. The study concludes that mostly composed of certain types of elites (NGOs, business communities, politicians and privileged social-cultural groups), non-state actors have used participatory policies to advance their own interests at the expense of the majority whom they claim to represent. These practices are traced to the historically unjust social, political, and economic forces involved in the production of space in Nairobi.

Keywords: eco-politics, exclusion, infrastructure, Nairobi national park, non-state actors, protests

Procedia PDF Downloads 156

Authors: Jacqueline Eleonora Ek, Michael Spiteri, Chris Giordimaina, Pierre Agius

Abstract:

Background: Malta is known for being a key player as a frontline country with regard to irregular immigration from Africa to Europe. Every year the island experiences an influx of migrants as boat movement across the Mediterranean continues to be a humanitarian challenge. Irregular immigration and applying for asylum is both a lengthy and mentally demanding process. Those doing so are often faced with multiple challenges, which can adversely affect their mental health. Between January and August 2020, Malta disembarked 2 162 people rescued at sea, 463 of them between July & August. Given the small size of the Maltese islands, this regulation places a disproportionately large burden on the country, creating a backlog in the processing of asylum applications resulting in increased time periods of detention. These delays reverberate throughout multiple management pathways resulting in prolonged periods of detention and challenging access to health services. Objectives: To better understand the spatial dimensions of this humanitarian crisis, this study aims to assess disparities in the acute medical management of migrants presenting to the emergency department (ED) with acute mental health presentations as compared to that of local and non-local residents. Method: In this retrospective study, 17795 consecutive ED attendances were reviewed to look for acute mental health presentations. These were further evaluated to assess discrepancies in transportation routes to hospital, nature of presenting complaint, effects of language barriers, use of CT brain, treatment given at ED, availability of psychiatric reviews, and final admission/discharge plans. Results: Of the ED attendances, 92.3% were local residents, and 7.7% were non-locals. Of the non-locals, 13.8% were migrants, and 86.2% were other-non-locals. Acute mental health presentations were seen in 1% of local residents; this increased to 20.6% in migrants. 56.4% of migrants attended with deliberate self-harm; this was lower in local residents, 28.9%. Contrastingly, in local residents, the most common presenting complaint was suicidal thought/ low mood 37.3%, the incidence was similar in migrants at 33.3%. The main differences included 12.8% of migrants presenting with refused oral intake while only 0.6% of local residents presented with the same complaints. 7.7% of migrants presented with a reduced level of consciousness, no local residents presented with this same issue. Physicians documented a language barrier in 74.4% of migrants. 25.6% were noted to be completely uncommunicative. Further investigations included the use of a CT scan in 12% of local residents and in 35.9% of migrants. The most common treatment administered to migrants was supportive fluids 15.4%, the most common in local residents was benzodiazepines 15.1%. Voluntary psychiatric admissions were seen in 33.3% of migrants and 24.7% of locals. Involuntary admissions were seen in 23% of migrants and 13.3% of locals. Conclusion: Results showed multiple disparities in health management. A meeting was held between entities responsible for migrant health in Malta, including the emergency department, primary health care, migrant detention services, and Malta Red Cross. Currently, national quality-improvement initiatives are underway to form new pathways to improve patient-centered care. These include an interpreter unit, centralized handover sheets, and a dedicated migrant health service.

Keywords: emergency department, communication, health, migration

Procedia PDF Downloads 87

Authors: Naniek Widayati Priyomarsono

Abstract:

Introduction: In beginning of Karaton formation, namely, era of Javanese kingdom town had the power region outside castle town (called as Mancanegara), settlement of karaton can function as “the space-between” and “space-defense”, besides it was one of components from governmental structure and karaton power at that time (internal servant/abdi dalem and sentana dalem). Upon the Independence of Indonesia in 1945 “Kingdom-City” converted its political status into part of democratic town managed by statutes based on the classification. The latter affects local culture hierarchy alteration due to the physical development and events. Dynamics of social economy activities in Kampung Karaton surrounded by buildings of Complex of Karaton Kasunanan ini, have impact on the urban system disturbed into the región. Also cultural region image fades away with the weak visual access from existant cultural artefacts. That development lacks of giving appreciation to the established region image providing identity of Karaton Kasunanan particularly and identity of Surakarta city in general. Method used is strategy of grounded theory research (research providing strong base of a theory). Research is focused on actors active and passive relevantly getting involved in change process of Karaton settlement. Data accumulated is “Investigation Focus” oriented on actors affecting that change either internal or external. Investigation results are coupled with field observation data, documentation, literature study, thus it takes accurate findings. Findings: Karaton village has potential products as attraction, possessing human resource support, strong motivation from society still living in that settlement, possessing facilities and means supports, tourism event-supporting facilities, cultural art institution, available fields or development area. Data analyzed: To get the expected result it takes restoration in social cultural development direction, and economy, with ways of: Doing social cultural development strategy, economy, and politics. To-do steps are program socialization of Karaton village as Tourism Village, economical development of local society, regeneration pattern, filtering, and selection of tourism development, integrated planning system development, development with persuasive approach, regulation, market mechanism, social cultural event sector development, political development for region activity sector. Summary: In case the restoration is done by getting society involved as subject of that settlement (active participation in the field), managed and packed interestingly and naturally with tourism-supporting facilities development, village of Karaton Kasunanan Surakarta is ready to receive visit of domestic and foreign tourists.

Keywords: karaton village, finding, restoration, economy, Indonesia

Procedia PDF Downloads 417

Authors: Anubhav Kumar Dwivedi, Arshad Khan, S. N. Tripathi, Manish Joshi, Gaurav Mishra, Dinesh Nath, Naveen Tiwari, B. K. Sapra

Abstract:

In a nuclear reactor accident scenario, a large number of fission products may release to the piping system of the primary heat transport. The released fission products, mostly in the form of the aerosol, get deposited on the inner surface of the piping system mainly due to gravitational settling and thermophoretic deposition. The removal processes in the complex piping system are controlled to a large extent by the thermal-hydraulic conditions like temperature, pressure, and flow rates. These parameters generally vary with time and therefore must be carefully monitored to predict the aerosol behavior in the piping system. The removal process of aerosol depends on the size of particles that determines how many particles get deposit or travel across the bends and reach to the other end of the piping system. The released aerosol gets deposited onto the inner surface of the piping system by various mechanisms like gravitational settling, Brownian diffusion, thermophoretic deposition, and by other deposition mechanisms. To quantify the correct estimate of deposition, the identification and understanding of the aforementioned deposition mechanisms are of great importance. These mechanisms are significantly affected by different flow and thermodynamic conditions. Thermophoresis also plays a significant role in particle deposition. In the present study, a series of experiments were performed in the piping system of the National Aerosol Test Facility (NATF), BARC using metal aerosols (zinc) in dry environments to study the spatial distribution of particles mass and number concentration, and their depletion due to various removal mechanisms in the piping system. The experiments were performed at two different carrier gas flow rates. The commercial CFD software FLUENT is used to determine the distribution of temperature, velocity, pressure, and turbulence quantities in the piping system. In addition to the in-built models for turbulence, heat transfer and flow in the commercial CFD code (FLUENT), a new sub-model PBM (population balance model) is used to describe the coagulation process and to compute the number concentration along with the size distribution at different sections of the piping. In the sub-model coagulation kernels are incorporated through user-defined function (UDF). The experimental results are compared with the CFD modeled results. It is found that most of the Zn particles (more than 35 %) deposit near the inlet of the plenum chamber and a low deposition is obtained in piping sections. The MMAD decreases along the length of the test assembly, which shows that large particles get deposited or removed in the course of flow, and only fine particles travel to the end of the piping system. The effect of a bend is also observed, and it is found that the relative loss in mass concentration at bends is more in case of a high flow rate. The simulation results show that the thermophoresis and depositional effects are more dominating for the small and larger sizes as compared to the intermediate particles size. Both SEM and XRD analysis of the collected samples show the samples are highly agglomerated non-spherical and composed mainly of ZnO. The coupled model framed in this work could be used as an important tool for predicting size distribution and concentration of some other aerosol released during a reactor accident scenario.

Keywords: aerosol, CFD, deposition, coagulation

Procedia PDF Downloads 126

Authors: Bello Gonzalez T. D. J., Setten Van M., Essen Van A., Brouwer M., Veldman K. T.

Abstract:

Resistance to fluoroquinolones (FQ) has evolved increasingly over the years, posing a significant challenge for the treatment of human infections, particularly gastrointestinal tract infections caused by zoonotic bacteria transmitted through the food chain and environment. In broiler chickens, a relatively high proportion of FQ resistance has been observed in Escherichia coli indicator, Salmonella and Campylobacter isolates. We hypothesize that flumequine (Flu), used as a secondary choice for the treatment of poultry infections, could potentially be associated with a high proportion of FQ resistance. To evaluate this hypothesis, we used an in vitro fermentation chicken caeca model. Two continuous single-stage fermenters were used to simulate in real time the physiological conditions of the chicken caeca microbial content (temperature, pH, caecal content mixing, and anoxic environment). A pool of chicken caecal content containing FQ-resistant E. coli obtained from chickens at slaughter age was used as inoculum along with a spiked FQ-susceptible Campylobacter jejuni strain isolated from broilers. Flu was added to one of the fermenters (Flu-fermenter) every 24 hours for two days to evaluate the selection and maintenance of FQ resistance over time, while the other served as a control (C-Fermenter). The experiment duration was 5 days. Samples were collected at three different time points: before, during and after Flu administration. Serial dilutions were plated on Butzler culture media with and without Flu (8mg/L) and enrofloxacin (4mg/L) and on MacConkey culture media with and without Flu (4mg/L) and enrofloxacin (1mg/L) to determine the proportion of resistant strains over time. Positive cultures were identified by mass spectrometry and matrix-assisted laser desorption/ionization (MALDI). A subset of the obtained isolates were used for Whole Genome Sequencing analysis. Over time, E. coli exhibited positive growth in both fermenters, while C. jejuni growth was detected up to day 3. The proportion of Flu-resistant E. coli strains recovered remained consistent over time after antibiotic selective pressure, while in the C-fermenter, a decrease was observed at day 5; a similar pattern was observed in the enrofloxacin-resistant E. coli strains. This suggests that Flu might play a role in the selection and persistence of enrofloxacin resistance, compared to C-fermenter, where enrofloxacin-resistant E. coli strains appear at a later time. Furthermore, positive growth was detected from both fermenters only on Butzler plates without antibiotics. A subset of C. jejuni strains from the Flu-fermenter revealed that those strains were susceptible to ciprofloxacin (MIC < 0.12 μg/mL). A selection of E. coli strains from both fermenters revealed the presence of plasmid-mediated quinolone resistance (PMQR) (qnr-B19) in only one strain from the C-fermenter belonging to sequence type (ST) 48, and in all from Flu-fermenter belonged to ST189. Our results showed that Flu selective impact on PMQR-positive E. coli strains, while no effect was observed in C. jejuni. Maintenance of Flu-resistance was correlated with antibiotic selective pressure. Further studies into antibiotic resistance gene transfer among commensal and zoonotic bacteria in the chicken caeca content may help to elucidate the resistance spread mechanisms.

Keywords: fluoroquinolone-resistance, escherichia coli, campylobacter jejuni, in vitro model

Procedia PDF Downloads 36

Authors: Ayush Aditya

Abstract:

In today's digitised world, the extent of an individual’s social involvement is largely determined by their interaction over the internet. The Internet has emerged as a primary source of information consumption and a reliable medium for receiving updates on everyday activities. Owing to this change in the information consumption pattern, the internet has also emerged as a hotbed of misinformation. Experts are of the view that media literacy has emerged as one of the most effective strategies for addressing the issue of misinformation. This paper aims to study the evolution of the Kerala government's media literacy policy, its implementation strategy, challenges and opportunities. The objective of this paper is to create a conceptual framework containing details of the implementation strategy based on the Kerala model. Extensive secondary research of literature, newspaper articles, and other online sources was carried out to locate the timeline of this policy. This was followed by semi-structured interview discussions with government officials from Kerala to trace the origin and evolution of this policy. Preliminary findings based on the collected data suggest that this policy is a case of policy by chance, as the officer who headed this policy during the state level implementation was the one who has already piloted a media literacy program in a district called Kannur as the district collector. Through this paper, an attempt is made to trace the history of the media literacy policy starting from the Kannur intervention in 2018, which was started to address the issue of vaccine hesitancy around measles rubella(MR) vaccination. If not for the vaccine hesitancy, this program would not have been rolled out in Kannur. Interviews with government officials suggest that when authorities decided to take up this initiative in 2020, a huge amount of misinformation emerging during the COVID-19 pandemic was the trigger. There was misinformation regarding government orders, healthcare facilities, vaccination, and lockdown regulations, which affected everyone, unlike the case of Kannur, where it was only a certain age group of kids. As a solution to this problem, the state government decided to create a media literacy curriculum to be taught in all government schools of the state starting from standard 8 till graduation. This was a tricky task, as a new course had to be immediately introduced in the school curriculum amid all the disruptions in the education system caused by the pandemic. It was revealed during the interview that in the case of the state-wide implementation, every step involved multiple checks and balances, unlike the earlier program where stakeholders were roped-in as and when the need emerged. On the pedagogy, while the training during the pilot could be managed through PowerPoint presentation, designing a state-wide curriculum involved multiple iterations and expert approvals. The reason for this is COVID-19 related misinformation has lost its significance. In the next phase of the research, an attempt will be made to compare other aspects of the pilot implementation with the state-wide implementation.

Keywords: media literacy, digital media literacy, curriculum based media literacy intervention, misinformation

Procedia PDF Downloads 66

Authors: Anugrah Tripathi, H. S. Ginwal, Charul Kainthola

Abstract:

Bamboos are considered as valuable resources which have the potential of meeting current economic, environmental and social needs. Bamboo has played a key role in humankind and its livelihood since ancient time. Distributed in diverse areas across the globe, bamboo makes an important natural resource for hundreds of millions of people across the world. In some of the Asian countries and northeast part of India, bamboo is the basis of life on many horizons. India possesses the largest bamboo-bearing area across the world and a great extent of species richness, but this rich genetic resource and its diversity have dwindled in the natural forest due to forest fire, over exploitation, lack of proper management policies, and gregarious flowering behavior. Bamboos which are well known for their peculiar, extraordinary morphology, show a lot of variation in many scales. Among the various bamboo species, Dendrocalamus strictus is the most abundant bamboo resource in India, which is a deciduous, solid, and densely tufted bamboo. This species can thrive in wide gradients of geographical as well as climatic conditions. Due to this, it exhibits a significant amount of variation among the populations of different origins for numerous morphological features. Morphological parameters are the front-line criteria for the selection and improvement of any forestry species. Study on the diversity among eight important morphological characters of D. strictus was carried out, covering 16 populations from wide geographical locations of India following INBAR standards. Among studied 16 populations, three populations viz. DS06 (Gaya, Bihar), DS15 (Mirzapur, Uttar Pradesh), and DS16 (Bhogpur, Pinjore, Haryana) were found as superior populations with higher mean values for parametric characters (clump height, no. of culms/ clump, circumference of clump, internode diameter and internode length) and with the higher sum of ranks in non-parametric characters (straightness, disease, and pest incidence and branching pattern). All of these parameters showed an ample amount of variations among the studied populations and revealed a significant difference among the populations. Variation in morphological characters is very common in a species having wide distribution and is usually evident at various levels, viz., between and within the populations. They are of paramount importance for growth, biomass, and quick production gains. Present study also gives an idea for the selection of the population on the basis of these morphological parameters. From this study on morphological parameters and their variation, we may find an overview of best-performing populations for growth and biomass accumulation. Some of the studied parameters also provide ideas to standardize mechanisms of selecting and sustainable harvesting of the clumps by applying simpler silvicultural systems so that they can be properly managed in homestead gardens for the community utilization as well as by commercial growers to meet the requirement of industries and other stakeholders.

Keywords: Dendrocalamus strictus, homestead garden, gregarious flowering, stakeholders, INBAR

Procedia PDF Downloads 49

Authors: Jessica Arthur, Duke Amegah, Kingsley Akenten Wiafe

Abstract:

Background: Vanilla planifolia is the only edible fruit of the orchid family (Orchidaceae) among the over 35,000 Orchidaceae species found worldwide. In Ghana, Vanilla was discovered in the wild, but it is underutilized for commercial production, most likely due to a lack of knowledge on the best NAA and BAP combinations for in vitro propagation to promote successfully regenerated plant acclimatization. The growing interest and global demand for elite Vanilla planifolia plants and natural vanilla flavour emphasize the need for an effective industrial-scale micropropagation protocol. Tissue culture systems are increasingly used to grow disease-free plants and reliable in vitro methods can also produce plantlets with typically modest proliferation rates. This study sought to develop an efficient protocol for in vitro propagation of vanilla using nodal explants by testing different concentrations of NAA and BAP, for the proliferation of the entire plant. Methods: Nodal explants with dormant axillary buds were obtained from year-old laboratory-grown Vanilla planifolia plants. MS media was prepared with a nutrient stock solution (containing macronutrients, micronutrients, iron solution and vitamins) and semi-solidified using phytagel. It was supplemented with different concentrations of NAA and BAP to induce multiple shoots and roots (0.5mg/L BAP with NAA at 0, 0.5, 1, 1.5, 2.0mg/L and vice-versa). The explants were sterilized, cultured in labelled test tubes and incubated at 26°C ± 2°C with 16/8 hours light/dark cycle. Data on shoot and root growth, leaf number, node number, and survival percentage were collected over three consecutive two-week periods. The data were square root transformed and subjected to ANOVA and LSD at a 5% significance level using the R statistical package. Results: Shoots emerged at 8 days and roots at 12 days after inoculation with 94% survival rate. It was discovered that for the NAA treatments, MS media supplemented with 2.00 mg/l NAA resulted in the highest shoot length (10.45cm), maximum root number (1.51), maximum shoot number (1.47) and the highest number of leaves (1.29). MS medium containing 1.00 mg/l NAA produced the highest number of nodes (1.62) and root length (14.27cm). Also, a similar growth pattern for the BAP treatments was observed. MS medium supplemented with 1.50 mg/l BAP resulted in the highest shoot length (14.98 cm), the highest number of nodes (4.60), the highest number of leaves (1.75) and the maximum shoot number (1.57). MS medium containing 0.50 mg/l BAP and 1.0 mg/l BAP generated a maximum root number (1.44) and the highest root length (13.25cm), respectively. However, the best concentration combination for maximizing shoot and root was media containing 1.5mg/l BAP combined with 0.5mg/l NAA, and 1.0mg/l NAA combined with 0.5mg/l of BAP respectively. These concentrations were optimum for in vitro growth and production of Vanilla planifolia. Significance: This study presents a standardized protocol for labs to produce clean vanilla plantlets, enhancing cultivation in Ghana and beyond. It provides insights into Vanilla planifolia's growth patterns and hormone responses, aiding future research and cultivation.

Keywords: Vanilla planifolia, In vitro propagation, plant hormones, MS media

Procedia PDF Downloads 36

Authors: Mingqian Zhang

Abstract:

Tip-enhanced Raman spectroscopy (TERS) is a scanning probe technique for individual objects and structured surfaces investigation that provides a wealth of enhanced spectral information with nanoscale spatial resolution and high detection sensitivity. It has become a powerful and promising chemical and physical information detection method in the nanometer scale. The TERS technique uses a sharp metallic tip regulated in the near-field of a sample surface, which is illuminated with a certain incident beam meeting the excitation conditions of the wave-vector matching. The local electric field, and, consequently, the Raman scattering, from the sample in the vicinity of the tip apex are both greatly tip-enhanced owning to the excitation of localized surface plasmons and the lightning-rod effect. Typically, a TERS setup is composed of a scanning probe microscope, excitation and collection optical configurations, and a Raman spectroscope. In the illumination configuration, an objective lens or a parabolic mirror is always used as the most important component, in order to focus the incident beam on the tip apex for excitation. In this research, a novel TERS setup was built up by introducing a plasmonic lens to the excitation optics as a focusing device. A plasmonic lens with symmetry breaking semi-annular slits corrugated on gold film was designed for the purpose of generating concentrated sub-wavelength light spots with strong longitudinal electric field. Compared to conventional far-field optical components, the designed plasmonic lens not only focuses an incident beam to a sub-wavelength light spot, but also realizes a strong z-component that dominants the electric field illumination, which is ideal for the excitation of tip-enhancement. Therefore, using a PL in the illumination configuration of TERS contributes to improve the detection sensitivity by both reducing the far-field background and effectively exciting the localized electric field enhancement. The FDTD method was employed to investigate the optical near-field distribution resulting from the light-nanostructure interaction. And the optical field distribution was characterized using an scattering-type scanning near-field optical microscope to demonstrate the focusing performance of the lens. The experimental result is in agreement with the theoretically calculated one. It verifies the focusing performance of the plasmonic lens. The optical field distribution shows a bright elliptic spot in the lens center and several arc-like side-lobes on both sides. After the focusing performance was experimentally verified, the designed plasmonic lens was used as a focusing component in the excitation configuration of TERS setup to concentrate incident energy and generate a longitudinal optical field. A collimated linearly polarized laser beam, with along x-axis polarization, was incident from the bottom glass side on the plasmonic lens. The incident light focused by the plasmonic lens interacted with the silver-coated tip apex and enhanced the Raman signal of the sample locally. The scattered Raman signal was gathered by a parabolic mirror and detected with a Raman spectroscopy. Then, the plasmonic lens based setup was employed to investigate carbon nanotubes and TERS experiment was performed. Experimental results indicate that the Raman signal is considerably enhanced which proves that the novel TERS configuration is feasible and promising.

Keywords: longitudinal electric field, plasmonics, raman spectroscopy, tip-enhancement

Procedia PDF Downloads 352