Search results for: functional magnetic resonance imaging (fMRI)

Authors: Abdul Rahman Hamdan

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The Fourth Industrial Revolution (4IR) has brought unprecedented technological advancements that have disrupted many industries worldwide. In keeping up with the technological advances and rapid disruption by the introduction of many technological advancements brought forth by the 4IR, the use of technology road mapping has emerged as one of the critical tools for organizations to leverage. Technology road mapping can be used by many companies to guide them to become more adaptable and anticipate future transformation and innovation, and avoid being redundant or irrelevant due to the rapid changes in technological advancement. This research paper provides a comprehensive analysis of technology road mapping within the context of the 4IR. The objectives of the paper are to provide companies with practical insights and a strategic framework of technology road mapping for them to navigate the fast-changing nature of the 4IR. This study also contributes to the understanding and practice of technology road mapping in the 4IR and, at the same time, provides organizations with the necessary tools and critical insight to navigate the 4IR transformation by leveraging technology road mapping. Based on the literature review and case studies, the study analyses key principles, methodologies, and best practices in technology road mapping and integrates them with the unique characteristics and challenges of the 4IR. The research paper gives the background of the fourth industrial revolution. It explores the disruptive potential of technologies in the 4IR and the critical need for technology road mapping that consists of strategic planning and foresight to remain competitive and relevant in the 4IR era. It also highlights the importance of technology road mapping as an organisation’s proactive approach to align the organisation’s objectives and resources to their technology and product development in meeting the fast-evolving technological 4IR landscape. The paper also includes the theoretical foundations of technology road mapping and examines various methodological approaches, and identifies external stakeholders in the process, such as external experts, stakeholders, collaborative platforms, and cross-functional teams to ensure an integrated and robust technological roadmap for the organisation. Moreover, this study presents a comprehensive framework for technology road mapping in the 4IR by incorporating key elements and processes such as technology assessment, competitive intelligence, risk analysis, and resource allocation. It provides a framework for implementing technology road mapping from strategic planning, goal setting, and technology scanning to road mapping visualisation, implementation planning, monitoring, and evaluation. In addition, the study also addresses the challenges and limitations related to technology roadmapping in 4IR, including the gap analysis. In conclusion of the study, the study will propose a set of practical recommendations for organizations that intend to leverage technology road mapping as a strategic tool in the 4IR in driving innovation and becoming competitive in the current and future ecosystem.

Keywords: technology management, technology road mapping, technology transfer, technology planning

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Authors: Simon Ayorinde Okanlawon

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The youths’ prevalent negative attitude to farming is partly due to amenities and facilities found in the urban centers at the expense of the rural areas. Hence, there is the need to create a befitting and conducive farm environment to retain farm employees and attract the youth to farming. This can be achieved through the provision of services and amenities that will ensure a comfortable standard of living higher than that obtained by a person of equal status in other forms of employment in urban centers, thereby eliminating the psychological feeling of lowered self-esteem associated with farming. This study assessed farm settlements’ facilities and patronage in Oyo State with a view to using the information to encourage sustainable agriculture in Nigeria. The study becomes necessary because of the dearth of information on the state of facilities in the farm settlements as it affects patronage of farm settlements for sustainable agriculture in the developing countries like Nigeria. The study utilized three purposely selected farm settlements- Ogbomoso, Fasola and Ilora out of the seven existing ones n Oyo State. One hundred percent (100%) of the 262 residential buildings in the three settlements were sampled, from where a household head from each of the buildings was randomly chosen. This translates to 262 household heads served with questionnaire out of which 47.7% of the questionnaires were recovered. Information obtained included respondents’ residency categories, residents’ status, residency years, housing types, types of holding and number of acres/holding. Others include the socio-economic attributes such as age, gender, income, educational status of respondents, assessment of existing facilities in the selected sites, the level of patronage of the farm settlements including perceived pull factors that can enhance farm settlements patronage. The study revealed that the residents were not satisfied with the adequacy and quality of all the facilities available in their settlements. Residents’ satisfaction with infrastructural facilities cannot be statistically linked with location across the study area. Findings suggested that residents of Ogbomoso farm settlements were not enjoying adequate provision of water supply and road as much as those from Ilora and Fasola. Patronage of the farm settlements were largely driven by farming activities and sale of farm produce. The respondents agreed that provision of farm resort centers, standard recreational and tourism facilities, vacation employment opportunities for youths, functional internet and communication networks among others are likely to boost the level of patronage of the farm settlements. The study concluded that improvement of the facilities both in quality and quantity will encourage the youths in going back to farming. It then recommends that maintenance of existing facilities and provision of more facilities such as resort centers be ensured.

Keywords: encourage, farm settlements' facilities, Oyo state, patronage

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Authors: Riza Adriyani, Tommy Apriantono, Suprijanto

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Objective: Several studies have revealed that flatfoot posture has some effect on altered lower limb muscle function, in comparison to normal foot posture. There were still limited studies to examine the effect of fatigue on flatfoot posture in children. Therefore, this study was aimed to find out jumping fatiguing effect on static balance and to compare lower limb muscle function between flatfoot and normal foot in school children. Methods: Thirty junior high school children aged 12 to 14 years took part in this study. Of these all children, 15 had the normal foot (8 males and 7 females) and 15 had flatfoot (6 males and 9 females). Foot posture was classified based on an arch index of the footprint by a foot scanner which calculated the data using AUTOCAD 2013 software. Surface electromyography (EMG) activity was recorded from tibialis anterior, gastrocnemius medialis, and peroneus longus muscles while those participants were standing on one leg barefoot with opened eyes. All participants completed the entire protocol (pre-fatigue data collection, fatigue protocol, and post fatigue data collection) in a single session. Static balance and electromyographic data were collected before and after a functional fatigue protocol. Results: School children with normal foot had arch index 0.25±0.01 whereas those with flatfoot had 0.36±0.01. In fact, there were no significant differences for anthropometric characteristics between children with flatfoot and normal foot. This statistical analysis showed that fatigue could influence static balance in flatfoot school children (p < 0.05), but not in normal foot school children. Based on electromyographic data, the statistical analysis showed that there were significant differences (p < 0.05) of the decreased median frequency on tibialis anterior in flatfoot compared to normal foot school children after fatigue. However, there were no significant differences on the median frequency of gastrocnemius medialis and peroneus longus between both groups. After fatigue, median frequency timing was significantly different (p < 0.05) on tibialis anterior in flatfoot compared to normal foot children and tended to appear earlier on tibialis anterior, gastrocnemius medialis and peroneus longus (at 7s, 8s, 9s) in flatfoot compared to normal foot (at 15s, 11s , 12s). Conclusion: Fatigue influenced static balance and tended to appear earlier on selected lower limb muscles while performing static balance in flatfoot school children. After fatigue, tremor (median frequency decreased) showed more significant differences on tibialis anterior in flatfoot rather than in normal foot school children.

Keywords: fatigue, foot postures, median frequency, static balance

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Authors: Aloke Bapli, Debabrata Seth

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Graphene oxide (GO) is the two-dimensional (2D) nanoscale allotrope of carbon having several physiochemical properties such as high mechanical strength, high surface area, strong thermal and electrical conductivity makes it an important candidate in various modern applications such as drug delivery, supercapacitors, sensors etc. GO has been used in the photothermal treatment of cancers and Alzheimer’s disease etc. The main idea to choose GO in our work is that it is a surface active molecule, it has a large number of hydrophilic functional groups such as carboxylic acid, hydroxyl, epoxide on its surface and in basal plane. So it can easily interact with organic fluorophores through hydrogen bonding or any other kind of interaction and easily modulate the photophysics of the probe molecules. We have used different spectroscopic techniques for our work. The Ground-state absorption spectra and steady-state fluorescence emission spectra were measured by using UV-Vis spectrophotometer from Shimadzu (model-UV-2550) and spectrofluorometer from Horiba Jobin Yvon (model-Fluoromax 4P) respectively. All the fluorescence lifetime and anisotropy decays were collected by using time-correlated single photon counting (TCSPC) setup from Edinburgh instrument (model: LifeSpec-II, U.K.). Herein, we described the photophysics of a hydrophilic molecule 7-(n,n׀-diethylamino) coumarin-3-carboxylic acid (7-DCCA) in the reverse micelles containing GO. It was observed that photophysics of dye is modulated in the presence of GO compared to photophysics of dye in the absence of GO inside the reverse micelles. Here we have reported the solvent relaxation and rotational relaxation time in GO containing reverse micelle and compare our work with normal reverse micelle system by using 7-DCCA molecule. Normal reverse micelle means reverse micelle in the absence of GO. The absorption maxima of 7-DCCA were blue shifted and emission maxima were red shifted in GO containing reverse micelle compared to normal reverse micelle. The rotational relaxation time in GO containing reverse micelle is always faster compare to normal reverse micelle. Solvent relaxation time, at lower w₀ values, is always slower in GO containing reverse micelle compare to normal reverse micelle and at higher w₀ solvent relaxation time of GO containing reverse micelle becomes almost equal to normal reverse micelle. Here emission maximum of 7-DCCA exhibit bathochromic shift in GO containing reverse micelles compared to that in normal reverse micelles because in presence of GO the polarity of the system increases, as polarity increases the emission maxima was red shifted an average decay time of GO containing reverse micelle is less than that of the normal reverse micelle. In GO containing reverse micelle quantum yield, decay time, rotational relaxation time, solvent relaxation time at λₑₓ=375 nm is always higher than λₑₓ=405 nm, shows the excitation wavelength dependent photophysics of 7-DCCA in GO containing reverse micelles.

Keywords: photophysics, reverse micelle, rotational relaxation, solvent relaxation

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Authors: George Pavlidis, Ana Vivas

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The demographic change into an aging population has stimulated the examination of seniors’ mental health and ability to live independently. The corresponding literature depicts the relation between cognitive decline and everyday functionality with aging, focusing largely in individuals that are reaching or have bridged the threshold of various forms of neuropathology and disability. In this context, recent meta-analysis depicts a moderate relation between cognitive performance and everyday functionality in AD sufferers. However, there has not been an analogous effort for the examination of this relation in the healthy spectrum of aging (i.e, in samples that are not challenged from a neurodegenerative disease). There is a consensus that the assessment tools designed to detect neuropathology with those that assess cognitive performance in healthy adults are distinct, thus their universal use in cognitively challenged and in healthy adults is not always valid. The same accounts for the assessment of everyday functionality. In addition, it is argued that everyday functionality should be examined with cultural adjusted assessment tools, since many vital everyday tasks are heterotypical among distinct cultures. Therefore, this study was set out to examine the relation between cognitive performance and everyday functionality a) in the healthy spectrum of aging and b) by adjusting the everyday functionality tools EPT and OTDL-R in the Greek cultural context. In Greece, 107 cognitively healthy seniors ( Mage = 62.24) completed a battery of neuropsychological tests and everyday functionality tests. Both were carefully chosen to be sensitive in fluctuations of performance in the healthy spectrum of cognitive performance and everyday functionality. The everyday functionality assessment tools were modified to reflect the local cultural context (i.e., EPT-G and OTDL-G). The results depicted that performance in all everyday functionality measures decline with age (.197 < r > .509). Statistically significant correlations emerged between cognitive performance and everyday functionality assessments that range from r =0.202 to r=0.510. A series of independent regression analysis including the scores of cognitive assessments has yield statistical significant models that explained 20.9 < AR2 > 32.4 of the variance in everyday functionality scored indexes. All everyday functionality measures were independently predicted by the TMT B-A index, and indicator of executive function. Stepwise regression analyses depicted that TMT B-A and age were statistically significant independent predictors of EPT-G and OTDL-G. It was concluded that everyday functionality is declining with age and that cognitive performance and everyday functional may be related in the healthy spectrum of aging. Age seems not to be the sole contributing factor in everyday functionality decline, rather executive control as well. Moreover, it was concluded that the EPT-G and OTDL-G are valuable tools to assess everyday functionality in Greek seniors that are not cognitively challenged, especially for research purposes. Future research should examine the contributing factors of a better cognitive vitality especially in executive control, as vital for the maintenance of independent living capacity with aging.

Keywords: cognition, everyday functionality, aging, cognitive decline, healthy aging, Greece

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Authors: Thiago E. Goto, Carla C. Lopes, Helena B. Nader, Anielle C. A. Silva, Noelio O. Dantas, José R. Siqueira Jr., Luciano Caseli

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Quantum dots (QD) are semiconductor nanocrystals that can be employed in biological research as a tool for fluorescence imagings, having the potential to expand in vivo and in vitro analysis as cancerous cell biomarkers. Particularly, cadmium selenide (CdSe) magic-sized quantum dots (MSQDs) exhibit stable luminescence that is feasible for biological applications, especially for imaging of tumor cells. For these facts, it is interesting to know the mechanisms of action of how such QDs mark biological cells. For that, simplified models are a suitable strategy. Among these models, Langmuir films of lipids formed at the air-water interface seem to be adequate since they can mimic half a membrane. They are monomolecular films formed at liquid-gas interfaces that can spontaneously form when organic solutions of amphiphilic compounds are spread on the liquid-gas interface. After solvent evaporation, the monomolecular film is formed, and a variety of techniques, including tensiometric, spectroscopic and optic can be applied. When the monolayer is formed by membrane lipids at the air-water interface, a model for half a membrane can be inferred where the aqueous subphase serve as a model for external or internal compartment of the cell. These films can be transferred to solid supports forming the so-called Langmuir-Blodgett (LB) films, and an ampler variety of techniques can be additionally used to characterize the film, allowing for the formation of devices and sensors. With these ideas in mind, the objective of this work was to investigate the specific interactions of CdSe MSQDs with tumorigenic and non-tumorigenic cells using Langmuir monolayers and LB films of lipids and specific cell extracts as membrane models for diagnosis of cancerous cells. Surface pressure-area isotherms and polarization modulation reflection-absorption spectroscopy (PM-IRRAS) showed an intrinsic interaction between the quantum dots, inserted in the aqueous subphase, and Langmuir monolayers, constructed either of selected lipids or of non-tumorigenic and tumorigenic cells extracts. The quantum dots expanded the monolayers and changed the PM-IRRAS spectra for the lipid monolayers. The mixed films were then compressed to high surface pressures and transferred from the floating monolayer to solid supports by using the LB technique. Images of the films were then obtained with atomic force microscopy (AFM) and confocal microscopy, which provided information about the morphology of the films. Similarities and differences between films with different composition representing cell membranes, with or without CdSe MSQDs, was analyzed. The results indicated that the interaction of quantum dots with the bioinspired films is modulated by the lipid composition. The properties of the normal cell monolayer were not significantly altered, whereas for the tumorigenic cell monolayer models, the films presented significant alteration. The images therefore exhibited a stronger effect of CdSe MSQDs on the models representing cancerous cells. As important implication of these findings, one may envisage for new bioinspired surfaces based on molecular recognition for biomedical applications.

Keywords: biomembrane, langmuir monolayers, quantum dots, surfaces

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Authors: Chiao-Cheng Huang, Pei-Te Chiueh, Ya-Hsuan Liou

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Chromium-contaminated wastewater from electroplating industrial activity has been a long-standing environmental issue, as it can degrade surface water quality and is harmful to soil ecosystems. The traditional method of treating chromium-contaminated wastewater has been to use chemical coagulation processes. However, this method consumes large amounts of chemicals such as sulfuric acid, sodium hydroxide, and sodium bicarbonate in order to remove chromium. However, a series of new methods for treating chromium-containing wastewater have been developed. This study aimed to compare the environmental impact of four different lab scale chromium removal processes: 1.) chemical coagulation process (the most common and traditional method), in which sodium metabisulfite was used as reductant, 2.) electrochemical process using two steel sheets as electrodes, 3.) reduction by iron-copper bimetallic powder, and 4.) photocatalysis process by TiO2. Each process was run in the lab, and was able to achieve 100% removal of chromium in solution. Then a Life Cycle Assessment (LCA) study was conducted based on the experimental data obtained from four different case studies to identify the environmentally preferable alternative to treat chromium wastewater. The model used for calculating the environmental impact was TRACi, and the system scope includes the production phase and use phase of chemicals and electricity consumed by the chromium removal processes, as well as the final disposal of chromium containing sludge. The functional unit chosen in this study was the removal of 1 mg of chromium. Solution volume of each case study was adjusted to 1 L in advance and the chemicals and energy consumed were proportionally adjusted. The emissions and resources consumed were identified and characterized into 15 categories of midpoint impacts. The impact assessment results show that the human ecotoxicity category accounts for 55 % of environmental impact in Case 1, which can be attributed to the sulfuric acid used for pH adjustment. In Case 2, production of steel sheet electrodes is an energy-intensive process, thus contributed to 20 % of environmental impact. In Case 3, sodium bicarbonate is used as an anti-corrosion additive, which results mainly in 1.02E-05 Comparative Toxicity Unit (CTU) in the human toxicity category and 0.54E-05 (CTU) in acidification of air. In Case 4, electricity consumption for power supply of UV lamp gives 5.25E-05 (CTU) in human toxicity category, 1.15E-05 (kg Neq) in eutrophication. In conclusion, Case 3 and Case 4 have higher environmental impacts than Case 1 and Case 2, which can be attributed mostly to higher energy and chemical consumption, leading to high impacts in the global warming and ecotoxicity categories.

Keywords: chromium, lab scale, life cycle assessment, wastewater

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Authors: Martin Juckel

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Probably no other field of inorganic chemistry has undergone such a rapid development in the past two decades than the low oxidation state chemistry of main group elements. This rapid development has only been possible by the development of new bulky ligands. In case of our research group, super-bulky monodentate amido ligands and β-diketiminate ligands have been used to a great success. We first synthesized the unprecedented magnesium(I) dimer [ᴹᵉˢNacnacMg]₂ (ᴹᵉˢNacnac = [(ᴹᵉˢNCMe)₂CH]-; Mes = mesityl, which has since been used both as reducing agent and also for the synthesis of new metal-magnesium bonds. In case of the zinc bromide precursor [L*ZnBr] (L*=(N(Ar*)(SiPri₃); (Ar* = C₆H₂{C(H)Ph₂}₂Me-2,6,4, the reduction with [ᴹᵉˢNacnacMg]₂ led to such a metal-magnesium bond. This [L*ZnMg(ᴹᵉˢNacnac)] compound can be seen as an ‘inorganic Grignard reagent’, which can be used to transfer the metal fragment onto other functional groups or other metal centers; just like the conventional Grignard reagent. By simple addition of (TBoN)GeCl (TBoN = N(SiMe₃){B(DipNCH)₂) to the aforesaid compound, we were able to transfer the amido-zinc fragment to the Ge center of the germylene starting material and to synthesize the first example of a germanium(II)-zinc bond: [:Ge(TBoN)(ZnL*)]. While these reactions typically led to complex product mixture, [:Ge(TBoN)(ZnL*)] could be isolated as dark blue crystals in a good yield. This new compound shows interesting reactivity towards small molecules, especially dihydrogen gas. This is of special interest as dihydrogen is one of the more difficult small molecules to activate, due to its strong (BDE = 108 kcal/mol) and non-polar bond. In this context, the interaction between H₂ σ-bond with the tetrelylene p-Orbital (LUMO), with concomitant donation of the tetrelylene lone pair (HOMO) into the H₂ σ* orbital are responsible for the activation of dihydrogen gas. Accordingly, the narrower the HOMO-LUMO gap of tertelylene, the more reactivity towards H₂ it typically is. The aim of a narrow HOMO-LUMO gap was reached by transferring electropositive substituents respectively metal substituents with relatively low Pauling electronegativity (zinc: 1.65) onto the Ge center (here: the zinc-amido fragment). In consideration of the unprecedented reactivity of [:Ge(TBoN)(ZnL*)], a computational examination of its frontier orbital energies was undertaken. The energy separation between the HOMO, which has significant Ge lone pair character, and the LUMO, which has predominantly Ge p-orbital character, is narrow (40.8 kcal/mol; cf.∆S-T= 24.8 kcal/mol), and comparable to the HOMO-LUMO gaps calculated for other literature known complexes). The calculated very narrow HOMO-LUMO gap for the [:Ge(TBoN)(ZnL*)] complex is consistent with its high reactivity, and is remarkable considering that it incorporates a π-basic amide ligand, which are known to raise the LUMO of germylenes considerably.

Keywords: activation of dihydrogen gas, narrow HOMO-LUMO gap, first germanium(II)-zinc bond, inorganic Grignard reagent

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Authors: Fereydoon Bondarian, Samira Shaygan

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Today, many nutritionists recommend the consumption of plants, fruits, and vegetables to provide the antioxidants needed by the body because the use of plant antioxidants usually causes fewer side effects and better treatment. Natural antioxidants increase the power of plasma antioxidants and reduce the incidence of some diseases, such as cancer. Bad lifestyles and environmental factors play an important role in increasing the incidence of cancer. In this study, different extracts of white teas taken from two types of tea available in Iran (clone 100 and Chinese hybrid) due to the presence of a hydroxyl functional group in their structure to inhibit free radicals and anticancer properties, using 3 aqueous, methanolic and aqueous-methanolic methods were used. The total polyphenolic content was calculated using the Folin-Ciocalcu method, and the percentage of inhibition and trapping of free radicals in each of the extracts was calculated using the DPPH method. With the help of high-performance liquid chromatography, a small amount of each catechin in the tea samples was obtained. Clone 100 white tea was found to be the best sample of tea in terms of all the examined attributes (total polyphenol content, antioxidant properties, and individual amount of each catechin). The results showed that aqueous and aqueous-methanolic extracts of Clone 100 white tea have the highest total polyphenol content with 27.59±0.08 and 36.67±0.54 (equivalent gallic acid per gram dry weight of leaves), respectively. Due to having the highest level of different groups of catechin compounds, these extracts have the highest property of inhibiting and trapping free radicals with 66.61±0.27 and 71.74±0.27% (mg/l) of the extracted sample against ascorbic acid). Using the MTT test, the inhibitory effect of clone 100 white tea extract in inhibiting the growth of HCT-116 colon cancer cells was investigated and the best time and concentration treatments were 500, 150 and 1000 micrograms in 8, 16 and 24 hours, respectively. To investigate gene expression changes, selected genes, including tumorigenic genes, proto-oncogenes, tumor suppressors, and genes involved in apoptosis, were selected and analyzed using the real-time PCR method and in the presence of concentrations obtained for white tea. White tea extract at a concentration of 1000 μg/ml 3 times 16, 8, and 24 hours showed the highest growth inhibition in cancer cells with 53.27, 55.8, and 86.06%. The concentration of 1000 μg/ml aqueous extract of white tea under 24-hour treatment increased the expression of tumor suppressor genes compared to the normal sample.

Keywords: catechin, gene expression, suppressor genes, colon cell line

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Authors: Hossein Aghababaei, Sergio Vitale, Giampaolo Ferraioli

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In the context of Synthetic Aperture Radar (SAR) data, polarization is an important source of information for Earth's surface monitoring. SAR Systems are often considered to transmit only one polarization. This constraint leads to either single or dual polarimetric SAR imaging modalities. Single polarimetric systems operate with a fixed single polarization of both transmitted and received electromagnetic (EM) waves, resulting in a single acquisition channel. Dual polarimetric systems, on the other hand, transmit in one fixed polarization and receive in two orthogonal polarizations, resulting in two acquisition channels. Dual polarimetric systems are obviously more informative than single polarimetric systems and are increasingly being used for a variety of remote sensing applications. In dual polarimetric systems, the choice of polarizations for the transmitter and the receiver is open. The choice of circular transmit polarization and coherent dual linear receive polarizations forms a special dual polarimetric system called hybrid polarimetry, which brings the properties of rotational invariance to geometrical orientations of features in the scene and optimizes the design of the radar in terms of reliability, mass, and power constraints. The complete characterization of target scattering, however, requires fully polarimetric data, which can be acquired with systems that transmit two orthogonal polarizations. This adds further complexity to data acquisition and shortens the coverage area or swath of fully polarimetric images compared to the swath of dual or hybrid polarimetric images. The search for solutions to augment dual polarimetric data to full polarimetric data will therefore take advantage of full characterization and exploitation of the backscattered field over a wider coverage with less system complexity. Several methods for reconstructing fully polarimetric images using hybrid polarimetric data can be found in the literature. Although the improvements achieved by the newly investigated and experimented reconstruction techniques are undeniable, the existing methods are, however, mostly based upon model assumptions (especially the assumption of reflectance symmetry), which may limit their reliability and applicability to vegetation and forest scenarios. To overcome the problems of these techniques, this paper proposes a new framework for reconstructing fully polarimetric information from hybrid polarimetric data. The framework uses Deep Learning solutions to augment hybrid polarimetric data without relying on model assumptions. A convolutional neural network (CNN) with a specific architecture and loss function is defined for this augmentation problem by focusing on different scattering properties of the polarimetric data. In particular, the method controls the CNN training process with respect to several characteristic features of polarimetric images defined by the combination of different terms in the cost or loss function. The proposed method is experimentally validated with real data sets and compared with a well-known and standard approach from the literature. From the experiments, the reconstruction performance of the proposed framework is superior to conventional reconstruction methods. The pseudo fully polarimetric data reconstructed by the proposed method also agree well with the actual fully polarimetric images acquired by radar systems, confirming the reliability and efficiency of the proposed method.

Keywords: SAR image, polarimetric SAR image, convolutional neural network, deep learnig, deep neural network

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Authors: Varun Kumar, Chandra Shakher

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Micro-optical components such as microlenses and microlens array have numerous engineering and industrial applications for collimation of laser diodes, imaging devices for sensor system (CCD/CMOS, document copier machines etc.), for making beam homogeneous for high power lasers, a critical component in Shack-Hartmann sensor, fiber optic coupling and optical switching in communication technology. Also micro-optical components have become an alternative for applications where miniaturization, reduction of alignment and packaging cost are necessary. The compliance with high-quality standards in the manufacturing of micro-optical components is a precondition to be compatible on worldwide markets. Therefore, high demands are put on quality assurance. For quality assurance of these lenses, an economical measurement technique is needed. For cost and time reason, technique should be fast, simple (for production reason), and robust with high resolution. The technique should provide non contact, non-invasive and full field information about the shape of micro- optical component under test. The interferometric techniques are noncontact type and non invasive and provide full field information about the shape of the optical components. The conventional interferometric technique such as holographic interferometry or Mach-Zehnder interferometry is available for characterization of micro-lenses. However, these techniques need more experimental efforts and are also time consuming. Digital holography (DH) overcomes the above described problems. Digital holographic microscopy (DHM) allows one to extract both the amplitude and phase information of a wavefront transmitted through the transparent object (microlens or microlens array) from a single recorded digital hologram by using numerical methods. Also one can reconstruct the complex object wavefront at different depths due to numerical reconstruction. Digital holography provides axial resolution in nanometer range while lateral resolution is limited by diffraction and the size of the sensor. In this paper, Mach-Zehnder based digital holographic interferometric microscope (DHIM) system is used for the testing of transparent microlenses. The advantage of using the DHIM is that the distortions due to aberrations in the optical system are avoided by the interferometric comparison of reconstructed phase with and without the object (microlens array). In the experiment, first a digital hologram is recorded in the absence of sample (microlens array) as a reference hologram. Second hologram is recorded in the presence of microlens array. The presence of transparent microlens array will induce a phase change in the transmitted laser light. Complex amplitude of object wavefront in presence and absence of microlens array is reconstructed by using Fresnel reconstruction method. From the reconstructed complex amplitude, one can evaluate the phase of object wave in presence and absence of microlens array. Phase difference between the two states of object wave will provide the information about the optical path length change due to the shape of the microlens. By the knowledge of the value of the refractive index of microlens array material and air, the surface profile of microlens array is evaluated. The Sag of microlens and radius of curvature of microlens are evaluated and reported. The sag of microlens agrees well within the experimental limit as provided in the specification by the manufacturer.

Keywords: micro-optics, microlens array, phase map, digital holographic interferometric microscopy

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Authors: Cristina Lavilla, Andreas Heise

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The synthesis of sequence-controlled polymers has received increasing attention in the last years. Well-defined polyacrylates, polyacrylamides and styrene-maleimide copolymers have been synthesized by sequential or kinetic addition of comonomers. However this approach has not yet been introduced to the synthesis of polypeptides, which are in fact polymers developed by nature in a sequence-controlled way. Polypeptides are natural materials that possess the ability to self-assemble into complex and highly ordered structures. Their folding and properties arise from precisely controlled sequences and compositions in their constituent amino acid monomers. So far, solid-phase peptide synthesis is the only technique that allows preparing short peptide sequences with excellent sequence control, but also requires extensive protection/deprotection steps and it is a difficult technique to scale-up. A new strategy towards sequence control in the synthesis of polypeptides is introduced, based on the sequential addition of α-amino acid-N-carboxyanhydrides (NCAs). The living ring-opening process is conducted to full conversion and no purification or deprotection is needed before addition of a new amino acid. The length of every block is predefined by the NCA:initiator ratio in every step. This method yields polypeptides with a specific sequence and controlled molecular weights. A series of polypeptides with varying block sequences have been synthesized with the aim to identify structure-property relationships. All of them are able to adopt secondary structures similar to natural polypeptides, and display properties in the solid state and in solution that are characteristic of the primary structure. By design the prepared polypeptides allow selective modification of individual block sequences, which has been exploited to introduce functionalities in defined positions along the polypeptide chain. Poly(ethylene glycol)(PEG) was the functionality chosen, as it is known to favor hydrophilicity and also yield thermoresponsive materials. After PEGylation, hydrophilicity of the polypeptides is enhanced, and their thermal response in H2O has been studied. Noteworthy differences in the behavior of the polypeptides having different sequences have been found. Circular dichroism measurements confirmed that the α-helical conformation is stable over the examined temperature range (5-90 °C). It is concluded that PEG units are the main responsible of the changes in H-bonding interactions with H2O upon variation of temperature, and the position of these functional units along the backbone is a factor of utmost importance in the resulting properties of the α-helical polypeptides.

Keywords: α-amino acid N-carboxyanhydrides, multiblock copolymers, poly(ethylene glycol), polypeptides, ring-opening polymerization, sequence control

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Authors: Ali Zaker, Zhi Chen

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Due to the concerns about the depletion of fossil fuel sources and the deteriorating environment, the attempt to investigate the production of renewable energy will play a crucial role as a potential to alleviate the dependency on mineral fuels. One particular area of interest is the generation of bio-oil through sewage sludge (SS) pyrolysis. SS can be a potential candidate in contrast to other types of biomasses due to its availability and low cost. However, the presence of high molecular weight hydrocarbons and oxygenated compounds in the SS bio-oil hinders some of its fuel applications. In this context, catalytic pyrolysis is another attainable route to upgrade bio-oil quality. Among different catalysts (i.e., zeolites) studied for SS pyrolysis, activated chars (AC) are eco-friendly alternatives. The beneficial features of AC derived from SS comprise the comparatively large surface area, porosity, enriched surface functional groups, and presence of a high amount of metal species that can improve the catalytic activity. Hence, a sludge-based AC catalyst was fabricated in a single-step pyrolysis reaction with NaOH as the activation agent and was compared with HZSM5 zeolite in this study. The thermal decomposition and kinetics were invested via thermogravimetric analysis (TGA) for guidance and control of pyrolysis and catalytic pyrolysis and the design of the pyrolysis setup. The results indicated that the pyrolysis and catalytic pyrolysis contains four obvious stages, and the main decomposition reaction occurred in the range of 200-600°C. The Coats-Redfern method was applied in the 2nd and 3rd devolatilization stages to estimate the reaction order and activation energy (E) from the mass loss data. The average activation energy (Em) values for the reaction orders n = 1, 2, and 3 were in the range of 6.67-20.37 kJ for SS; 1.51-6.87 kJ for HZSM5; and 2.29-9.17 kJ for AC, respectively. According to the results, AC and HZSM5 both were able to improve the reaction rate of SS pyrolysis by abridging the Em value. Moreover, to generate and examine the effect of the catalysts on the quality of bio-oil, a fixed-bed pyrolysis system was designed and implemented. The composition analysis of the produced bio-oil was carried out via gas chromatography/mass spectrometry (GC/MS). The selected SS to catalyst ratios were 1:1, 2:1, and 4:1. The optimum ratio in terms of cracking the long-chain hydrocarbons and removing oxygen-containing compounds was 1:1 for both catalysts. The upgraded bio-oils with AC and HZSM5 were in the total range of C4-C17, with around 72% in the range of C4-C9. The bio-oil from pyrolysis of SS contained 49.27% oxygenated compounds, while with the presence of AC and HZSM5 dropped to 13.02% and 7.3%, respectively. Meanwhile, the generation of benzene, toluene, and xylene (BTX) compounds was significantly improved in the catalytic process. Furthermore, the fabricated AC catalyst was characterized by BET, SEM-EDX, FT-IR, and TGA techniques. Overall, this research demonstrated AC is an efficient catalyst in the pyrolysis of SS and can be used as a cost-competitive catalyst in contrast to HZSM5.

Keywords: catalytic pyrolysis, sewage sludge, activated char, HZSM5, bio-oil

Procedia PDF Downloads 150

Authors: P. J. Sweeney, T. Ahtoniemi, J. Puoliväli, T. Laitinen, K. Lehtimäki, A. Nurmi, D. Wells

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Duchenne muscular dystrophy (DMD) is caused by an X linked mutation in the dystrophin gene; lack of dystrophin causes a progressive muscle necrosis which leads to a progressive decrease in mobility in those suffering from the disease. The MDX mouse, a mutant mouse model which displays a frank dystrophinopathy, is currently widely employed in pre clinical efficacy models for treatments and therapies aimed at DMD. In general the end-points examined within this model have been based on invasive histopathology of muscles and serum biochemical measures like measurement of serum creatine kinase (sCK). It is established that a “critical period” between 4 and 6 weeks exists in the MDX mouse when there is extensive muscle damage that is largely sub clinical but evident with sCK measurements and histopathological staining. However, a full characterization of the MDX model remains largely incomplete especially with respect to the ability to aggravate of the muscle damage beyond the critical period. The purpose of this study was to attempt to aggravate the muscle damage in the MDX mouse and to create a wider, more readily translatable and discernible, therapeutic window for the testing of potential therapies for DMD. The study consisted of subjecting 15 male mutant MDX mice and 15 male wild-type mice to an intense chronic exercise regime that consisted of bi-weekly (two times per week) treadmill sessions over a 12 month period. Each session was 30 minutes in duration and the treadmill speed was gradually built up to 14m/min for the entire session. Baseline plasma creatine kinase (pCK), treadmill training performance and locomotor activity were measured after the “critical period” at around 10 weeks of age and again at 14 weeks of age, 6 months, 9 months and 12 months of age. In addition, kinematic gait analysis was employed using a novel analysis algorithm in order to compare changes in gait and fine motor skills in diseased exercised MDX mice compared to exercised wild type mice and non exercised MDX mice. In addition, a morphological and metabolic profile (including lipid profile), from the muscles most severely affected, the gastrocnemius muscle and the tibialis anterior muscle, was also measured at the same time intervals. Results indicate that by aggravating or exacerbating the underlying muscle damage in the MDX mouse by exercise a more pronounced and severe phenotype in comes to light and this can be picked up earlier by kinematic gait analysis. A reduction in mobility as measured by open field is not apparent at younger ages nor during the critical period, but changes in gait are apparent in the mutant MDX mice. These gait changes coincide with pronounced morphological and metabolic changes by non-invasive anatomical MRI and proton spectroscopy (1H-MRS) we have reported elsewhere. Evidence of a progressive asymmetric pathology in imaging parameters as well as in the kinematic gait analysis was found. Taken together, the data show that chronic exercise regime exacerbates the muscle damage beyond the critical period and the ability to measure through non-invasive means are important factors to consider when performing preclinical efficacy studies in the MDX mouse.

Keywords: Gait, muscular dystrophy, Kinematic analysis, neuromuscular disease

Procedia PDF Downloads 257

Authors: Stephen McCarthy, Joanne Gray, Esther Carr, Gerard Danjoux, Paul Baker, Rhiannon Hackett

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Background: The Go Well Health (GWH) platform is a web-based programme that allows patients to access personalised care plans and resources, aimed at prehabilitation prior to surgery. The online digital platform delivers essential patient education and support for patients prior to undergoing total hip replacements (THR) and total knee replacements (TKR). This study evaluated the impact of an online digital platform (ODP) in terms of functional health outcomes, health related quality of life and hospital length of stay following surgery. Methods: A retrospective cohort study comparing a cohort of patients who used the online digital platform (ODP) to deliver patient education and support (PES) prior to undergoing THR and TKR surgery relative to a cohort of patients who did not access the ODP and received usual care. Routinely collected Patient Reported Outcome Measures (PROMs) data was obtained on 2,406 patients who underwent a knee replacement (n=1,160) or a hip replacement (n=1,246) between 2018 and 2019 in a single surgical centre in the United Kingdom. The Oxford Hip and Knee Score and the European Quality of Life Five-Dimensional tool (EQ5D-5L) was obtained both pre-and post-surgery (at 6 months) along with hospital LOS. Linear regression was used to compare the estimate the impact of GWH on both health outcomes and negative binomial regressions were used to impact on LOS. All analyses adjusted for age, sex, Charlson Comorbidity Score and either pre-operative Oxford Hip/Knee scores or pre-operative EQ-5D scores. Fractional polynomials were used to represent potential non-linear relationships between the factors included in the regression model. Findings: For patients who underwent a knee replacement, GWH had a statistically significant impact on Oxford Knee Scores and EQ5D-5L utility post-surgery (p=0.039 and p=0.002 respectively). GWH did not have a statistically significant impact on the hospital length of stay. For those patients who underwent a hip replacement, GWH had a statistically significant impact on Oxford Hip Scores and EQ5D-5L utility post (p=0.000 and p=0.009 respectively). GWH also had a statistically significant reduction in the hospital length of stay (p=0.000). Conclusion: Health Outcomes were higher for patients who used the GWH platform and underwent THR and TKR relative to those who received usual care prior to surgery. Patients who underwent a hip replacement and used GWH also had a reduced hospital LOS. These findings are important for health policy and or decision makers as they suggest that prehabilitation via an ODP can maximise health outcomes for patients following surgery whilst potentially making efficiency savings with reductions in LOS.

Keywords: digital prehabilitation, online digital platform, orthopaedics, surgery

Procedia PDF Downloads 167

Authors: Vilma Sasyte, Vilma Viliene, Agila Dauksiene, Asta Raceviciute-Stupeliene, Romas Gruzauskas, Saulius Alijosius

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The eight-week feeding trial was conducted involving 27-wk-old Isa brown laying hens to study the effect of dry extrusion processing on partial reduction in total glucosinolates content of locally produced rapeseed and on productivity and eggs quality parameters of laying hens. Thirty-six hens were randomly assigned one of three treatments (CONTR, AERS and HERS), each comprising 12, individual caged layers. The main composition of the diets was the same, but extruded soya bean seed were replaced with 2.5% of the extruded rapeseed in the AERS group and 4.5 % in the HERS group. Rapeseed was extruded together with faba beans. Due to extrusion process the glucosinolates content was reduced by 7.83 µmol/g of rapeseed. The results of conducted trial shows, that during all experimental period egg production parameters, such as the average feed intake (6529.17 vs. 6257 g/hen/14 day; P < 0.05) and laying intensity (94.35% vs. 89.29; P < 0.05) were statistically different for HERS and CONTR laying hens respectively. Only the feed conversion ratio to produce 1 kg of eggs, kg in AERS group was by 11 % lower compared to CONTR group (P < 0.05). By analysing the effect of extruded rapeseed on egg mass, the statistical differences between treatments were no determined. The dietary treatments did not affect egg weight, albumen height, haugh units, albumen and yolk pH. However, in the HERS group were get eggs with the more intensive yolk color, higher redness (a) and yellowness (b) values. The inclusion of full-fat extruded rapeseed had no effect on egg shell quality parameters, i.e. shell breaking strength, shell weight with and without coat and shell index, but in the experimental groups were get eggs with the thinner shell (P < 0.05). The internal egg quality analysis showed that with higher content of extruded rapeseed (4.5 %) level in the diet, the total cholesterol in the eggs yolk decreased by 1.92 mg/g in comparison with CONTR group (P < 0.05). Eggs laid by hens fed the diet containing 2.5% and 4.5% had increasing ∑PNRR/∑SRR ratio and decreasing ∑(n-6)/∑(n-3) ratio values of eggs yolk fatty acids than in CONTR group. Eggs of hens fed different amount of extruded rapeseed presented an n-6 : n-3 ratio changed from 5.17 to 4.71. The analysis of the relationship between hypocholesteremia/ hypercholesterolemia fatty acids (H/H), which is based on the functional properties of fatty acids, found that the value of it ratio is significant higher in laying hens fed diets supplemented with 4.5% extruded rapeseed than the CONTR group, demonstrating the positive effects of extruded rapeseed on egg quality. The results of trial confirmed that extruded full fat rapeseed to the 4.5% are suitable to replace soyabean in the compound feed of laying hens.

Keywords: egg quality, extruded full-fat rapeseed, laying hens, productivity

Procedia PDF Downloads 192

Authors: Kyohei Yoshino, Masahiko Matsumiya, Yuji Sasaki

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Recently, studies have been conducted on Au(III) extraction using ionic liquids (ILs) as extractants or diluents. ILs such as piperidinium, pyrrolidinium, and pyridinium have been studied as extractants for noble metal extractions. Furthermore, the polarity, hydrophobicity, and solvent miscibility of these ILs can be adjusted depending on their intended use. Therefore, the unique properties of ILs make them functional extraction media. The extraction mechanism of Au(III) using phosphonium-based ILs and relevant thermodynamic studies are yet to be reported. In the present work, we focused on the mechanism of Au(III) extraction and related thermodynamic analyses using phosphonium-based ILs. Triethyl-n-pentyl, triethyl-n-octyl, and triethyl-n-dodecyl phosphonium bis(trifluoromethyl-sulfonyl)amide, [P₂₂₂ₓ][NTf₂], (X = 5, 8, and 12) were investigated for Au(III) extraction. The IL–Au complex was identified as [P₂₂₂₅][AuCl₄] using UV–Vis–NIR and Raman spectroscopic analyses. The extraction behavior of Au(III) was investigated with a change in the [P₂₂₂ₓ][NTf₂]IL concentration from 1.0 × 10–4 to 1.0 × 10–1 mol dm−3. The results indicate that Au(III) can be easily extracted by the anion-exchange reaction in the [P₂₂₂ₓ][NTf₂]IL. The slope range 0.96–1.01 on the plot of log D vs log[P₂₂₂ₓ][NTf2]IL indicates the association of one mole of IL with one mole of [AuCl4−] during extraction. Consequently, [P₂₂₂ₓ][NTf₂] is an anion-exchange extractant for the extraction of Au(III) in the form of anions from chloride media. Thus, this type of phosphonium-based IL proceeds via an anion exchange reaction with Au(III). In order to evaluate the thermodynamic parameters on the Au(III) extraction, the equilibrium constant (logKₑₓ’) was determined from the temperature dependence. The plot of the natural logarithm of Kₑₓ’ vs the inverse of the absolute temperature (T–1) yields a slope proportional to the enthalpy (ΔH). By plotting T–1 vs lnKₑₓ’, a line with a slope range 1.129–1.421 was obtained. Thus, the result indicated that the extraction reaction of Au(III) using the [P₂₂₂ₓ][NTf₂]IL (X=5, 8, and 12) was exothermic (ΔH=-9.39〜-11.81 kJ mol-1). The negative value of TΔS (-4.20〜-5.27 kJ mol-1) indicates that microscopic randomness is preferred in the [P₂₂₂₅][NTf₂]IL extraction system over [P₂₂₂₁₂][NTf₂]IL. The total negative alternation in Gibbs energy (-5.19〜-6.55 kJ mol-1) for the extraction reaction would thus be relatively influenced by the TΔS value on the number of carbon atoms in the alkyl side length, even if the efficiency of ΔH is significantly influenced by the total negative alternations in Gibbs energy. Electrochemical analysis revealed that extracted Au(III) can be reduced in two steps: (i) Au(III)/Au(I) and (ii) Au(I)/Au(0). The diffusion coefficients of the extracted Au(III) species in [P₂₂₂ₓ][NTf₂] (X = 5, 8, and 12) were evaluated from 323 to 373 K using semi-integral and semi-differential analyses. Because of the viscosity of the IL medium, the diffusion coefficient of the extracted Au(III) increases with increasing alkyl chain length. The 4f7/2 spectrum based on X-ray photoelectron spectroscopy revealed that the Au electrodeposits obtained after 10 cycles of continuous extraction and electrodeposition were in the metallic state.

Keywords: au(III), electrodeposition, phosphonium-based ionic liquids, solvent extraction

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Authors: Hossein Aghababaei, Sergio Vitale, Giampaolo ferraioli

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In the context of Synthetic Aperture Radar (SAR) data, polarization is an important source of information for Earth's surface monitoring . SAR Systems are often considered to transmit only one polarization. This constraint leads to either single or dual polarimetric SAR imaging modalities. Single polarimetric systems operate with a fixed single polarization of both transmitted and received electromagnetic (EM) waves, resulting in a single acquisition channel. Dual polarimetric systems, on the other hand, transmit in one fixed polarization and receive in two orthogonal polarizations, resulting in two acquisition channels. Dual polarimetric systems are obviously more informative than single polarimetric systems and are increasingly being used for a variety of remote sensing applications. In dual polarimetric systems, the choice of polarizations for the transmitter and the receiver is open. The choice of circular transmit polarization and coherent dual linear receive polarizations forms a special dual polarimetric system called hybrid polarimetry, which brings the properties of rotational invariance to geometrical orientations of features in the scene and optimizes the design of the radar in terms of reliability, mass, and power constraints. The complete characterization of target scattering, however, requires fully polarimetric data, which can be acquired with systems that transmit two orthogonal polarizations. This adds further complexity to data acquisition and shortens the coverage area or swath of fully polarimetric images compared to the swath of dual or hybrid polarimetric images. The search for solutions to augment dual polarimetric data to full polarimetric data will therefore take advantage of full characterization and exploitation of the backscattered field over a wider coverage with less system complexity. Several methods for reconstructing fully polarimetric images using hybrid polarimetric data can be found in the literature. Although the improvements achieved by the newly investigated and experimented reconstruction techniques are undeniable, the existing methods are, however, mostly based upon model assumptions (especially the assumption of reflectance symmetry), which may limit their reliability and applicability to vegetation and forest scenarios. To overcome the problems of these techniques, this paper proposes a new framework for reconstructing fully polarimetric information from hybrid polarimetric data. The framework uses Deep Learning solutions to augment hybrid polarimetric data without relying on model assumptions. A convolutional neural network (CNN) with a specific architecture and loss function is defined for this augmentation problem by focusing on different scattering properties of the polarimetric data. In particular, the method controls the CNN training process with respect to several characteristic features of polarimetric images defined by the combination of different terms in the cost or loss function. The proposed method is experimentally validated with real data sets and compared with a well-known and standard approach from the literature. From the experiments, the reconstruction performance of the proposed framework is superior to conventional reconstruction methods. The pseudo fully polarimetric data reconstructed by the proposed method also agree well with the actual fully polarimetric images acquired by radar systems, confirming the reliability and efficiency of the proposed method.

Keywords: SAR image, deep learning, convolutional neural network, deep neural network, SAR polarimetry

Procedia PDF Downloads 50

Authors: Kanti Sapkota, Do Hyun Lee, Sung Soo Han

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Nanocomposites have been widely used in various fields such as electronics, catalysis, and in chemical, biological, biomedical and optical fields. They display broad biomedical properties like antidiabetic, anticancer, antioxidant, antimicrobial and antibacterial activities. Moreover, nanomaterials have been used for wastewater treatment. Particularly, bimetallic hybrid nanocomposites exhibit unique features as compared to their monometallic components. Hybrid nanomaterials not only afford the multifunctionality endowed by their constituents but can also show synergistic properties. In addition, these hybrid nanomaterials have noteworthy catalytic and optical properties. Notably, Au−Ag based nanoparticles can be employed in sensor and catalysis due to their characteristic composition-tunable plasmonic properties. Due to their importance and usefulness, various efforts were developed for their preparation. Generally, chemical methods have been described to synthesize such bimetallic nanocomposites. In such chemical synthesis, harmful and hazardous chemicals cause environmental contamination and increase toxicity levels. Therefore, ecologically benevolent processes for the synthesis of nanomaterials are highly desirable to diminish such environmental and safety concerns. In this regard, here we disclose a simple, cost-effective, external additive free and eco-friendly method for the synthesis of Au-Ag@AgCl nanocomposites using Nephrolepis cordifolia root extract. Au-Ag@AgCl NCs were obtained by the simultaneous reduction of cationic Ag and Au into AgCl in the presence of plant extract. The particle size of 10 to 50 nm was observed with the average diameter of 30 nm. The synthesized nanocomposite was characterized by various modern characterization techniques. For example, UV−visible spectroscopy was used to determine the optical activity of the synthesized NCs, and Fourier transform infrared (FT-IR) spectroscopy was employed to investigate the functional groups present in the biomolecules that were responsible for both reducing and capping agents during the formation of nanocomposites. Similarly, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and energy-dispersive X-ray (EDX) spectroscopy were used to determine crystallinity, size, oxidation states, thermal stability and weight loss of the synthesized nanocomposites. As a synthetic application, the synthesized nanocomposite exhibited excellent catalytic activity for the multicomponent synthesis of biologically interesting quinoline molecules via domino annulation-aromatization reaction of aniline, arylaldehyde, and phenyl acetylene derivatives. Interestingly, the nanocatalyst was efficiently recycled for five times without substantial loss of catalytic properties.

Keywords: nanoparticles, catalysis, multicomponent, quinoline

Procedia PDF Downloads 97

Authors: Asta Sarkauskiene

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The pedagogy of Olympic education is based upon the main idea of P. de Coubertin, that physical education can and has to support the education of the perfect person, the one who was an aspiration in archaic Greece, when it was looking towards human as a one whole, which is composed of three interconnected functions: physical, psychical and spiritual. The following research question was formulated in the present study: What curriculum of non-formal physical education in school can positively influence physical development of 11-13 years old children? The aim of this study was to formulate and implement curriculum of non-formal physical education, based on Olympic pedagogy, and assess its effectiveness for physical development of 11-13 years old children. The research was conducted in two stages. In the first stage 51 fifth grade children (Mage = 11.3 years) participated in a quasi-experiment for two years. Children were organized into 2 groups: E and C. Both groups shared the duration (1 hour) and frequency (twice a week) but were different in their education curriculum. Experimental group (E) worked under the program developed by us. Priorities of the E group were: training of physical powers in unity with psychical and spiritual powers; integral growth of physical development, physical activity, physical health, and physical fitness; integration of children with lower health and physical fitness level; content that corresponds children needs, abilities, physical and functional powers. Control group (C) worked according to NFPE programs prepared by teachers and approved by school principal and school methodical group. Priorities of the C group were: motion actions teaching and development; physical qualities training; training of the most physically capable children. In the second stage (after four years) 72 sixth graders (Mage = 13.00) attended in the research from the same comprehensive schools. Children were organized into first and second groups. The curriculum of the first group was modified and the second - the same as group C. The focus groups conducted anthropometric (height, weight, BMI) and physiometric (VC, right and left handgrip strength) measurements. Dependent t test indicated that over two years E and C group girls and boys height, weight, right and left handgrip strength indices increased significantly, p < 0.05. E group girls and boys BMI indices did not change significantly, p > 0.05, i.e. height and weight ratio of girls, who participated in NFPE in school, became more proportional. C group girls VC indices did not differ significantly, p > 0.05. Independent t test indicated that in the first and second research stage differences of anthropometric and physiometric measurements of the groups are not significant, p > 0.05. Formulated and implemented curriculum of non-formal education in school, based on olympic pedagogy, had the biggest positive influence on decreasing 11-13 years old children level of BMI and increasing level of VC.

Keywords: non – formal physical education, olympic pedagogy, physical development, health sciences

Procedia PDF Downloads 532

Authors: Hossein Rezaie

Abstract:

Academic institutions, esp. universities, have been known as cradles of learning and teaching great thinkers while creating the type of knowledge that is supposed to be bereft of utilitarian motives. Nonetheless, it seems that such intellectual centers have entered into a competition with each other for attracting the attention of potential clients. The traditional values of (higher) education such as nurturing criticality and fostering intellectuality in students have been replaced with strategic planning, quality assurance, performance assessment, and academic audits. Not being immune from the whims and wishes of marketization, the system of higher education in the UK has been recalibrated by policy makers to address the demand and supply of student education, academic research and other university activities on the basis of monetary factors. As an immediate example in this vein, the Russell Group in the UK, which is comprised of 24 leading UK research universities, has explicitly expressed it policy on its official website as follows: ‘Russell Group universities are global businesses competing for staff, students and funding with the best in the world’. Furthermore, certain attempts have been made to corporatize the system of HE which have been manifested in remodeling of university governing bodies on corporate lines and developing measurement scales for indicating the performance of teaching practitioners. Nevertheless, it seems that such structural changes in policies toward the system of HE have bearing on the practices of practitioners and educators as well as the identity of students who are the customers of educational services. The effects of marketization have been examined mainly in terms of students’ perceptions and motivation, institutional policies and university management. However, the teaching practitioner side seems to be an under-studied area with regard to any changes in its expectations, satisfaction and perception of professional identity in the aftermath of introducing market-wise values into HE of the UK. As a result, this research aims to investigate the possible outcomes of market-driven values on the practitioner side of HE in the UK and finally seeks to address the following research questions: 1-How is the change in the mission of HE in the UK reflected in institutional documents? 1-A- How is the change of mission represented in job adverts? 1-B- How is the change of mission represented in university prospectuses? 2-How are teaching practitioners represented regarding their roles and obligations in the prospectuses and job ads published by UK HE institutions? In order to address these questions, the researcher will analyze 30 prospectuses and job ads published by Russel Group universities by taking Critical Discourse Analysis as his point of departure and the analytical methods of genre analysis and Systemic Functional Linguistics to probe into the generic features and representation of participants, in this case teaching practitioners, in the selected corpus.

Keywords: higher education, job advertisements, marketization of higher education, prospectuses

Procedia PDF Downloads 217

Authors: Ying-Chang Yu, Yuan-Lung Lo

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Building envelope design is one of the most popular design fields of architectural profession in nowadays. The main design trend of such system is to highlight the designer's aesthetic intention from the outlook of building project. Due to the trend of current façade design, the building envelope contains more and more layers of components, such as double skin façade, photovoltaic panels, solar control system, or even ornamental components. These exterior components are designed for various functional purposes. Most researchers focus on how these exterior elements should be structurally sound secured. However, not many researchers consider these elements would help to improve the performance of façade system. When the exterior elements are deployed in large scale, it creates an additional layer outside of original façade system and acts like a porous interface which would interfere with the aerodynamic of façade surface in micro-scale. A standard façade performance consists with 'water penetration, air infiltration rate, operation force, and component deflection ratio', and these key performances are majorly driven by the 'Design Wind Load' coded in local regulation. A design wind load is usually determined by the maximum wind pressure which occurs on the surface due to the geometry or location of building in extreme conditions. This research was designed to identify the air damping phenomenon of micro turbulence caused by porous exterior layer leading to surface wind load reduction for improvement of façade system performance. A series of wind tunnel test on dynamic pressure sensor array covered by various scale of porous exterior skin was conducted to verify the effect of wind pressure reduction. The testing specimens were designed to simulate the typical building with two-meter extension offsetting from building surface. Multiple porous exterior skins were prepared to replicate various opening ratio of surface which may cause different level of damping effect. This research adopted 'Pitot static tube', 'Thermal anemometers', and 'Hot film probe' to collect the data of surface dynamic pressure behind porous skin. Turbulence and distributed resistance are the two main factors of aerodynamic which would reduce the actual wind pressure. From initiative observation, the reading of surface wind pressure was effectively reduced behind porous media. In such case, an actual building envelope system may be benefited by porous skin from the reduction of surface wind pressure, which may improve the performance of envelope system consequently.

Keywords: multi-layer facade, porous media, facade performance, turbulence and distributed resistance, wind tunnel test

Procedia PDF Downloads 193

Authors: Baran Johansson

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This PhD dissertation aimed to explore children’s writing and reading in L1 (Persian) and L2 (Swedish). It adds new perspectives to reading and writing studies of bilingual biscriptal children with and without reading and writing difficulties (RWD). The study used standardised tests to examine linguistic and cognitive skills related to word reading and writing fluency in both languages. Furthermore, all participants produced two texts (one descriptive and one narrative) in each language. The writing processes and the writing product of these children were explored using logging methodologies (Eye and Pen) for both languages. Furthermore, this study investigated how two bilingual children with RWD presented themselves through writing across their languages. To my knowledge, studies utilizing standardised tests and logging tools to investigate bilingual children’s word reading and writing fluency across two different alphabetic scripts are scarce. There have been few studies analysing how bilingual children construct meaning in their writing, and none have focused on children who write in two different alphabetic scripts or those with RWD. Therefore, some aspects of the systemic functional linguistics (SFL) perspective were employed to examine how two participants with RWD created meaning in their written texts in each language. The results revealed that children with and without RWD had higher writing fluency in all measures (e.g. text lengths, writing speed) in their L2 compared to their L1. Word reading abilities in both languages were found to influence their writing fluency. The findings also showed that bilingual children without reading difficulties performed 1 standard deviation below the mean when reading words in Persian. However, their reading performance in Swedish aligned with the expected age norms, suggesting greater efficient in reading Swedish than in Persian. Furthermore, the results showed that the level of orthographic depth, consistency between graphemes and phonemes, and orthographic features can probably explain these differences across languages. The analysis of meaning-making indicated that the participants with RWD exhibited varying levels of difficulty, which influenced their knowledge and usage of writing across languages. For example, the participant with poor word recognition (PWR) presented himself similarly across genres, irrespective of the language in which he wrote. He employed the listing technique similarly across his L1 and L2. However, the participant with mixed reading difficulties (MRD) had difficulties with both transcription and text production. He produced spelling errors and frequently paused in both languages. He also struggled with word retrieval and producing coherent texts, consistent with studies of monolingual children with poor comprehension or with developmental language disorder. The results suggest that the mother tongue instruction provided to the participants has not been sufficient for them to become balanced biscriptal readers and writers in both languages. Therefore, increasing the number of hours dedicated to mother tongue instruction and motivating the children to participate in these classes could be potential strategies to address this issue.

Keywords: reading, writing, reading and writing difficulties, bilingual children, biscriptal

Procedia PDF Downloads 42

Authors: Geyang Xia

Abstract:

In many countries, governments have responded to the growing demand for educational resources through school district systems, and there is substantial evidence that school district systems have been effective in promoting inter-district and inter-school equity in educational resources. However, the scarcity of quality educational resources has brought about varying levels of education among different school districts, making it a common choice for many parents to buy a house in the school district where a quality school is located, and they are even willing to bear huge commuting costs for this purpose. Moreover, this is evidenced by the fact that parents of families in school districts with quality education resources have longer average commute lengths and longer average commute distances than parents in average school districts. This "unequal traveling" under the influence of the school district system is more common in school districts at the primary level of education. This further reinforces the differential hierarchy of educational resources and raises issues of inequitable educational public services, education-led residential segregation, and gentrification of school district housing. Against this background, this paper takes Nanjing, a famous educational city in China, as a case study and selects the school districts where the top 10 public elementary schools are located. The study first identifies the spatio-temporal behavioral trajectory dataset of these high-quality school district households by using spatial vector data, decrypted cell phone signaling data, and census data. Then, by constructing a "house-school-work (HSW)" commuting pattern of the population in the school district where the high-quality educational resources are located, and based on the classification of the HSW commuting pattern of the population, school districts with long employment hours were identified. Ultimately, the mechanisms and patterns inherent in this unequal commuting are analyzed in terms of six aspects, including the centrality of school district location, functional diversity, and accessibility. The results reveal that the "unequal commuting" of Nanjing's high-quality school districts under the influence of the school district system occurs mainly in the peripheral areas of the city, and the schools matched with these high-quality school districts are mostly branches of prestigious schools in the built-up areas of the city's core. At the same time, the centrality of school district location and the diversity of functions are the most important influencing factors of unequal commuting in high-quality school districts. Based on the research results, this paper proposes strategies to optimize the spatial layout of high-quality educational resources and corresponding transportation policy measures.

Keywords: school-district system, high quality school district, commuting pattern, unequal traveling

Procedia PDF Downloads 66

Authors: Nasser S. Shebka

Abstract:

Fuzzy logic is used in complex adaptive systems where classical tools of representing knowledge are unproductive. Nevertheless, the incorporation of fuzzy logic, as it’s the case with all artificial intelligence tools, raised some inconsistencies and limitations in dealing with increased complexity systems and rules that apply to real-life situations and hinders the ability of the inference process of such systems, but it also faces some inconsistencies between inferences generated fuzzy rules of complex or imprecise knowledge-based systems. The use of fuzzy logic enhanced the capability of knowledge representation in such applications that requires fuzzy representation of truth values or similar multi-value constant parameters derived from multi-valued logic, which set the basis for the three t-norms and their based connectives which are actually continuous functions and any other continuous t-norm can be described as an ordinal sum of these three basic ones. However, some of the attempts to solve this dilemma were an alteration to fuzzy logic by means of non-monotonic logic, which is used to deal with the defeasible inference of expert systems reasoning, for example, to allow for inference retraction upon additional data. However, even the introduction of non-monotonic fuzzy reasoning faces a major issue of conflict resolution for which many principles were introduced, such as; the specificity principle and the weakest link principle. The aim of our work is to improve the logical representation and functional modelling of AI systems by presenting a method of resolving existing and potential rule conflicts by representing temporal modalities within defeasible inference rule-based systems. Our paper investigates the possibility of resolving fuzzy rules conflict in a non-monotonic fuzzy reasoning-based system by introducing temporal modalities and Kripke's general weak modal logic operators in order to expand its knowledge representation capabilities by means of flexibility in classifying newly generated rules, and hence, resolving potential conflicts between these fuzzy rules. We were able to address the aforementioned problem of our investigation by restructuring the inference process of the fuzzy rule-based system. This is achieved by using time-branching temporal logic in combination with restricted first-order logic quantifiers, as well as propositional logic to represent classical temporal modality operators. The resulting findings not only enhance the flexibility of complex rule-base systems inference process but contributes to the fundamental methods of building rule bases in such a manner that will allow for a wider range of applicable real-life situations derived from a quantitative and qualitative knowledge representational perspective.

Keywords: fuzzy rule-based systems, fuzzy tense inference, intelligent systems, temporal modalities

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Authors: Jennifer Buz, Alvin Spivey

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The most common greenhouse gas emitted through human activities, carbon dioxide (CO2), is naturally consumed by plants during photosynthesis. This process is actively being monetized by companies wishing to offset their carbon dioxide emissions. For example, companies are now able to purchase protections for vegetated land due-to-be clear cut or purchase barren land for reforestation. Therefore, by actively preventing the destruction/decay of plant matter or by introducing more plant matter (reforestation), a company can theoretically offset some of their emissions. One of the biggest issues in the carbon credit market is validating and verifying carbon offsets. There is a need for a system that can accurately and frequently ensure that the areas sold for carbon credits have the vegetation mass (and therefore for carbon offset capability) they claim. Traditional techniques for measuring vegetation mass and determining health are costly and require many person-hours. Orbital Sidekick offers an alternative approach that accurately quantifies carbon mass and assesses vegetation health through satellite hyperspectral imagery, a technique which enables us to remotely identify material composition (including plant species) and condition (e.g., health and growth stage). How much carbon a plant is capable of storing ultimately is tied to many factors, including material density (primarily species-dependent), plant size, and health (trees that are actively decaying are not effectively storing carbon). All of these factors are capable of being observed through satellite hyperspectral imagery. This abstract focuses on speciation. To build a species classification model, we matched pixels in our remote sensing imagery to plants on the ground for which we know the species. To accomplish this, we collaborated with the researchers at the Teakettle Experimental Forest. Our remote sensing data comes from our airborne “Kato” sensor, which flew over the study area and acquired hyperspectral imagery (400-2500 nm, 472 bands) at ~0.5 m/pixel resolution. Coverage of the entire teakettle experimental forest required capturing dozens of individual hyperspectral images. In order to combine these images into a mosaic, we accounted for potential variations of atmospheric conditions throughout the data collection. To do this, we ran an open source atmospheric correction routine called ISOFIT1 (Imaging Spectrometer Optiman FITting), which converted all of our remote sensing data from radiance to reflectance. A database of reflectance spectra for each of the tree species within the study area was acquired using the Teakettle stem map and the geo-referenced hyperspectral images. We found that a wide variety of machine learning classifiers were able to identify the species within our images with high (>95%) accuracy. For the most robust quantification of carbon mass and the best assessment of the health of a vegetated area, speciation is critical. Through the use of high resolution hyperspectral data, ground-truth databases, and complex analytical techniques, we are able to determine the species present within a pixel to a high degree of accuracy. These species identifications will feed directly into our carbon mass model.

Keywords: hyperspectral, satellite, carbon, imagery, python, machine learning, speciation

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Authors: Laura Mion

Abstract:

Concepts of quality assurance and management are now part of the organizational culture of the Universities. Quality Assurance (QA) systems are, in large part, provided for by national regulatory dictates or supranational indications (such as, for example, at European level are, the ESG Guidelines "European Standard Guidelines"), but their specific definition, in terms of guiding principles, requirements and methodologies, are often delegated to the national evaluation agencies or to the autonomy of individual universities. For this reason, the experiences of implementation of QA systems in different countries and in different universities is an interesting source of information to understand how quality in universities is understood, pursued and verified. The literature often deals with the treatment of the experiences of implementation of QA systems in the individual areas in which the University's activity is carried out - teaching, research, third mission - but only rarely considers quality systems with a systemic and integrated approach, which allows to correlate subjects, actions, and performance in a virtuous circuit of continuous improvement. In particular, it is interesting to understand how to relate the results and uses of the QA in the triple distinction of university activities, identifying how one can cause the performance of the other as a function of an integrated whole and not as an exploit of specific activities or processes conceived in an abstractly atomistic way. The aim of the research is, therefore, to investigate which experiences of "integrated" QA systems are present on the international scene: starting from the experience of European countries that have long shared the Bologna Process for the creation of a European space for Higher Education (EHEA), but also considering experiences from emerging countries that use QA processes to develop their higher education systems to keep them up to date with international levels. The concept of "integration", in this research, is understood in a double meaning: i) between the different areas of activity, in particular between the didactic and research areas, and possibly with the so-called "third mission" "ii) the functional integration between those involved in quality assessment and management and the governance of the University. The paper will present the results of a systematic review conducted according with a method of an integrative review aimed at identifying best practices of quality assurance systems, in individual countries or individual universities, with a high level of integration. The analysis of the material thus obtained has made it possible to grasp common and transversal elements of QA system integration practices or particularly interesting elements and strengths of these experiences that can, therefore, be considered as winning aspects in a QA practice. The paper will present the method of analysis carried out, and the characteristics of the experiences identified, of which the structural elements will be highlighted (level of integration, areas considered, organizational levels included, etc.) and the elements for which these experiences can be considered as best practices.

Keywords: quality assurance, university, integration, country

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Authors: Iulianna Taritsa, Kuldeep Neote, Eric Fossel

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Lysosome-induced immunogenic cell death (LIICD) is a powerful mechanism of targeting cancer cells that kills circulating malignant cells and primes the host’s immune cells against future remission. Current immunotherapies for cancer are limited in preventing recurrence – a gap that can be bridged by training the immune system to recognize cancer neoantigens. Lysosomal leakage can be induced therapeutically to traffic antigens from dying cells to dendritic cells, which can later present those tumorigenic antigens to T cells. Previous research has shown that oxidative agents administered in the tumor microenvironment can initiate LIICD. We generated a fusion protein between an oxidative agent known as xanthine oxidase (XO) and a mini-antibody specific for EGFR/HER2-sensitive breast tumor cells. The anti-EGFR single domain antibody fragment is uniquely sourced from llama, which is functional without the presence of a light chain. These llama micro-antibodies have been shown to be better able to penetrate tissues and have improved physicochemical stability as compared to traditional monoclonal antibodies. We demonstrate that the fusion protein created is stable and can induce early markers of immunogenic cell death in an in vitro human breast cancer cell line (SkBr3). Specifically, we measured overall cell death, as well as surface-expressed calreticulin, extracellular ATP release, and HMGB1 production. These markers are consensus indicators of ICD. Flow cytometry, luminescence assays, and ELISA were used respectively to quantify biomarker levels between treated versus untreated cells. We also included a positive control group of SkBr3 cells dosed with doxorubicin (a known inducer of LIICD) and a negative control dosed with cisplatin (a known inducer of cell death, but not of the immunogenic variety). We looked at each marker at various time points after cancer cells were treated with the XO/antibody fusion protein, doxorubicin, and cisplatin. Upregulated biomarkers after treatment with the fusion protein indicate an immunogenic response. We thus show the potential for this fusion protein to induce an anticancer effect paired with an adaptive immune response against EGFR/HER2+ cells. Our research in human cell lines here provides evidence for the success of the same therapeutic method for patients and serves as the gateway to developing a new treatment approach against breast cancer.

Keywords: apoptosis, breast cancer, immunogenic cell death, lysosome

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Authors: Sara A. Pakvis, Giulia Scalet, Stefania Marconi, Ferdinando Auricchio, Matthijs Langelaar

Abstract:

In recent developments in the field of multi-material additive manufacturing, differences in material properties are exploited to create printed shape-memory structures, which are referred to as 4D-printed structures. New printing techniques allow for the deliberate introduction of prestresses in the specimen during manufacturing, and, in combination with the right design, this enables new functionalities. This research focuses on bi-polymer 4D-printed structures, where the transformation process is based on a heat-induced glass transition in one material lowering its Young’s modulus, combined with an initial prestress in the other material. Upon the decrease in stiffness, the prestress is released, which results in the realization of an essentially pre-programmed deformation. As the design of such functional multi-material structures is crucial but far from trivial, a systematic methodology to find the design of 4D-printed structures is developed, where a finite element model is combined with a density-based topology optimization method to describe the material layout. This modeling approach is verified by a convergence analysis and validated by comparing its numerical results to analytical and published data. Specific aspects that are addressed include the interplay between the definition of the prestress and the material interpolation function used in the density-based topology description, the inclusion of a temperature-dependent stiffness relationship to simulate the glass transition effect, and the importance of the consideration of geometric nonlinearity in the finite element modeling. The efficacy of topology optimization to design 4D-printed structures is explored by applying the methodology to a variety of design problems, both in 2D and 3D settings. Bi-layer designs composed of thermoplastic polymers are printed by means of the fused deposition modeling (FDM) technology. Acrylonitrile butadiene styrene (ABS) polymer undergoes the glass transition transformation, while polyurethane (TPU) polymer is prestressed by means of the 3D-printing process itself. Tests inducing shape transformation in the printed samples through heating are performed to calibrate the prestress and validate the modeling approach by comparing the numerical results to the experimental findings. Using the experimentally obtained prestress values, more complex designs have been generated through topology optimization, and samples have been printed and tested to evaluate their performance. This study demonstrates that by combining topology optimization and 4D-printing concepts, stimuli-responsive structures with specific properties can be designed and realized.

Keywords: 4D-printing, glass transition, shape memory polymer, topology optimization

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Authors: Philipp Wenger, Michael Beltle, Stefan Tenbohlen, Uwe Riechert

Abstract:

The integration of renewable energy introduces new challenges to the transmission grid, as the power generation is located far from load centers. The associated necessary long-range power transmission increases the demand for high voltage direct current (HVDC) transmission lines and DC distribution grids. HVDC gas-insulated switchgears (GIS) are considered being a key technology, due to the combination of the DC technology and the long operation experiences of AC-GIS. To ensure long-term reliability of such systems, insulation defects must be detected in an early stage. Operational experience with AC systems has proven evidence, that most failures, which can be attributed to breakdowns of the insulation system, can be detected and identified via partial discharge (PD) measurements beforehand. In AC systems the identification of defects relies on the phase resolved partial discharge pattern (PRPD). Since there is no phase information within DC systems this method cannot be transferred to DC PD diagnostic. Furthermore, the behaviour of e.g. free-moving particles differs significantly at DC: Under the influence of a constant direct electric field, charge carriers can accumulate on particles’ surfaces. As a result, a particle can lift-off, oscillate between the inner conductor and the enclosure or rapidly bounces at just one electrode, which is known as firefly motion. Depending on the motion and the relative position of the particle to the electrodes, broadband electromagnetic PD pulses are emitted, which can be recorded by ultra-high frequency (UHF) measuring methods. PDs are often accompanied by light emissions at the particle’s tip which enables optical detection. This contribution investigates PD characteristics of free moving metallic particles in a commercially available 300 kV SF6-insulated HVDC-GIS. The influences of various defect parameters on the particle motion and the PD characteristic are evaluated experimentally. Several particle geometries, such as cylinder, lamella, spiral and sphere with different length, diameter and weight are determined. The applied DC voltage is increased stepwise from inception voltage up to UDC = ± 400 kV. Different physical detection methods are used simultaneously in a time-synchronized setup. Firstly, the electromagnetic waves emitted by the particle are recorded by an UHF measuring system. Secondly, a photomultiplier tube (PMT) detects light emission with a wavelength in the range of λ = 185…870 nm. Thirdly, a high-speed camera (HSC) tracks the particle’s motion trajectory with high accuracy. Furthermore, an electrically insulated electrode is attached to the grounded enclosure and connected to a current shunt in order to detect low frequency ion currents: The shunt measuring system’s sensitivity is in the range of 10 nA at a measuring bandwidth of bw = DC…1 MHz. Currents of charge carriers, which are generated at the particle’s tip migrate through the gas gap to the electrode and can be recorded by the current shunt. All recorded PD signals are analyzed in order to identify characteristic properties of different particles. This includes e.g. repetition rates and amplitudes of successive pulses, characteristic frequency ranges and detected signal energy of single PD pulses. Concluding, an advanced understanding of underlying physical phenomena particle motion in direct electric field can be derived.

Keywords: current shunt, free moving particles, high-speed imaging, HVDC-GIS, UHF

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