Search results for: multi criteria decision making (MCDM)

Authors: Iman Farasat, Howard M. Salis

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Engineered genetic circuits reprogram cellular behavior to act as living computers with applications in detecting cancer, creating self-controlling artificial tissues, and dynamically regulating metabolic pathways. Phenemenological models are often used to simulate and design genetic circuit behavior towards a desired behavior. While such models assume that each circuit component’s function is modular and independent, even small changes in a circuit (e.g. a new promoter, a change in transcription factor expression level, or even a new media) can have significant effects on the circuit’s function. Here, we use statistical thermodynamics to account for the several factors that control transcriptional regulation in bacteria, and experimentally demonstrate the model’s accuracy across 825 measurements in several genetic contexts and hosts. We then employ our first principles model to design, experimentally construct, and characterize a family of signal amplifying genetic circuits (genetic OpAmps) that expand the dynamic range of cell sensors. To develop these models, we needed a new approach to measuring the in vivo binding free energies of transcription factors (TFs), a key ingredient of statistical thermodynamic models of gene regulation. We developed a new high-throughput assay to measure RNA polymerase and TF binding free energies, requiring the construction and characterization of only a few constructs and data analysis (Figure 1A). We experimentally verified the assay on 6 TetR-homolog repressors and a CRISPR/dCas9 guide RNA. We found that our binding free energy measurements quantitatively explains why changing TF expression levels alters circuit function. Altogether, by combining these measurements with our biophysical model of translation (the RBS Calculator) as well as other measurements (Figure 1B), our model can account for changes in TF binding sites, TF expression levels, circuit copy number, host genome size, and host growth rate (Figure 1C). Model predictions correctly accounted for how these 8 factors control a promoter’s transcription rate (Figure 1D). Using the model, we developed a design framework for engineering multi-promoter genetic circuits that greatly reduces the number of degrees of freedom (8 factors per promoter) to a single dimensionless unit. We propose the Ptashne (Pt) number to encapsulate the 8 co-dependent factors that control transcriptional regulation into a single number. Therefore, a single number controls a promoter’s output rather than these 8 co-dependent factors, and designing a genetic circuit with N promoters requires specification of only N Pt numbers. We demonstrate how to design genetic circuits in Pt number space by constructing and characterizing 15 2-repressor OpAmp circuits that act as signal amplifiers when within an optimal Pt region. We experimentally show that OpAmp circuits using different TFs and TF expression levels will only amplify the dynamic range of input signals when their corresponding Pt numbers are within the optimal region. Thus, the use of the Pt number greatly simplifies the genetic circuit design, particularly important as circuits employ more TFs to perform increasingly complex functions.

Keywords: transcription factor, synthetic biology, genetic circuit, biophysical model, binding energy measurement

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Authors: Jade V. Rushby, Tony Loughland, Tracy L. Durksen, Hoa Nguyen, Robert M. Klassen

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This paper reports a study investigating the development and implementation of an online multi-session ‘scenario-based learning’ (SBL) program administered to preservice teachers in Australia. The transition from initial teacher education to the teaching profession can present numerous cognitive and psychological challenges for early career teachers. Therefore, the identification of additional supports, such as scenario-based learning, that can supplement existing teacher education programs may help preservice teachers to feel more confident and prepared for the realities and complexities of teaching. Scenario-based learning is grounded in situated learning theory which holds that learning is most powerful when it is embedded within its authentic context. SBL exposes participants to complex and realistic workplace situations in a supportive environment and has been used extensively to help prepare students in other professions, such as legal and medical education. However, comparatively limited attention has been paid to investigating the effects of SBL in teacher education. In the present study, the SBL intervention provided participants with the opportunity to virtually engage with school-based scenarios, reflect on how they might respond to a series of plausible response options, and receive real-time feedback from experienced educators. The development process involved several stages, including collaboration with experienced educators to determine the scenario content based on ‘critical incidents’ they had encountered during their teaching careers, the establishment of the scoring key, the development of the expert feedback, and an extensive review process to refine the program content. The 4-part SBL program focused on areas that can be challenging in the beginning stages of a teaching career, including managing student behaviour and workload, differentiating the curriculum, and building relationships with colleagues, parents, and the community. Results from prior studies implemented by the research group using a similar 4-part format have shown a statistically significant increase in preservice teachers’ self-efficacy and classroom readiness from the pre-test to the final post-test. In the current research, professional teaching identity - incorporating self-efficacy, motivation, self-image, satisfaction, and commitment to teaching - was measured over six weeks at multiple time points: before, during, and after the 4-part scenario-based learning program. Analyses included latent growth curve modelling to assess the trajectory of change in the outcome variables throughout the intervention. The paper outlines (1) the theoretical underpinnings of SBL, (2) the development of the SBL program and methodology, and (3) the results from the study, including the impact of the SBL program on aspects of participating preservice teachers’ professional identity. The study shows how SBL interventions can be implemented alongside the initial teacher education curriculum to help prepare preservice teachers for the transition from student to teacher.

Keywords: classroom simulations, e-learning, initial teacher education, preservice teachers, professional learning, professional teaching identity, scenario-based learning, teacher development

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Authors: Julia Kapr, Andrea Rossi, Haribaskar Ramachandran, Marius Pollet, Ilka Egger, Selina Dangeleit, Katharina Koch, Jean Krutmann, Ellen Fritsche

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It is widely acknowledged that animal models do not always represent human disease. Especially human brain development is difficult to model in animals due to a variety of structural and functional species-specificities. This causes significant discrepancies between predicted and apparent drug efficacies in clinical trials and their subsequent failure. Emerging alternatives based on 3D in vitro approaches, such as human brain spheres or organoids, may in the future reduce and ultimately replace animal models. Here, we present a human induced pluripotent stem cell (hiPSC)-based 3D neural in a vitro disease model for the Cockayne Syndrome B (CSB). CSB is a rare hereditary disease and is accompanied by severe neurologic defects, such as microcephaly, ataxia and intellectual disability, with currently no treatment options. Therefore, the aim of this study is to investigate the molecular and cellular defects found in neural hiPSC-derived CSB models. Understanding the underlying pathology of CSB enables the development of treatment options. The two CSB models used in this study comprise a patient-derived hiPSC line and its isogenic control as well as a CSB-deficient cell line based on a healthy hiPSC line (IMR90-4) background thereby excluding genetic background-related effects. Neurally induced and differentiated brain sphere cultures were characterized via RNA Sequencing, western blot (WB), immunocytochemistry (ICC) and multielectrode arrays (MEAs). CSB-deficiency leads to an altered gene expression of markers for autophagy, focal adhesion and neural network formation. Cell migration was significantly reduced and electrical activity was significantly increased in the disease cell lines. These data hint that the cellular pathologies is possibly underlying CSB. By induction of autophagy, the migration phenotype could be partially rescued, suggesting a crucial role of disturbed autophagy in defective neural migration of the disease lines. Altered autophagy may also lead to inefficient mitophagy. Accordingly, disease cell lines were shown to have a lower mitochondrial base activity and a higher susceptibility to mitochondrial stress induced by rotenone. Since mitochondria play an important role in neurotransmitter cycling, we suggest that defective mitochondria may lead to altered electrical activity in the disease cell lines. Failure to clear the defective mitochondria by mitophagy and thus missing initiation cues for new mitochondrial production could potentiate this problem. With our data, we aim at establishing a disease adverse outcome pathway (AOP), thereby adding to the in-depth understanding of this multi-faced disorder and subsequently contributing to alternative drug development.

Keywords: autophagy, disease modeling, in vitro, pluripotent stem cells

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Authors: K. A.Veselova, N. V.Gromova, I. N.Antonova, I. N. Kalakutskii

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There are many diseases and incidents that may result facial defects and deformities: cancer, trauma, burns, congenital anomalies, and autoimmune diseases. In some cases, patient may acquire atypically extensive facial defect, including more than one anatomical region or, by contrast, atypically small defect (e.g. partial auricular defect). The anaplastology gives us opportunity to help patient with facial disfigurement in cases when plastic surgery is contraindicated. Using of implant retention for facial prosthesis is strongly recommended because improves both aesthetic and functional results and makes using of the prosthesis more comfortable. Prostheticly oriented fixture position is extremely important for aesthetic and functional long-term result; however, the optimal site for fixture placement is not clear in cases with atypical configuration of facial defect. The objective of this report is to demonstrate challenges in fixture position determination we have faced with and offer the solution. In this report, four cases of implant-supported facial prosthesis are described. Extra-oral implants with four millimeter length were used in all cases. The decision regarding the quantity of surgical stages was based on anamnesis of disease. Facial prostheses were manufactured according to conventional technique. Clinical and technological difficulties and mistakes are described, and prostheticly oriented approach for determination of fixture position is demonstrated. The case with atypically large combined orbital and nasal defect resulting after arteriovenous malformation is described: the correct positioning of artificial eye was impossible due to wrong position of the fixture (with suprastructure) located in medial aspect of supraorbital rim. The suprastructure was unfixed and this fixture wasn`t used for retention in order to achieve appropriate artificial eye placement and better aesthetic result. In other case with small partial auricular defect (only helix and antihelix were absent) caused by squamoized cell carcinoma T1N0M0 surgical template was used to avoid the difficulties. To achieve the prostheticly oriented fixture position in case of extremely small defect the template was made on preliminary cast using vacuum thermoforming method. Two radiopaque markers were incorporated into template in preferable for fixture placement positions taking into account future prosthesis configuration. The template was put on remaining ear and cone-beam CT was performed to insure, that the amount of bone is enough for implant insertion in preferable position. Before the surgery radiopaque markers were extracted and template was holed for guide drill. Fabrication of implant-retained facial prostheses gives us opportunity to improve aesthetics, retention and patients’ quality of life. But every inaccuracy in planning leads to challenges on surgery and prosthetic stages. Moreover, in cases with atypically small or extended facial defects prostheticly oriented approach for determination of fixture position is strongly required. The approach including surgical template fabrication is effective, easy and cheap way to avoid mistakes and unpredictable result.

Keywords: anaplastology, facial prosthesis, implant-retained facial prosthesis., maxillofacil prosthese

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Authors: Sayed Maeen Badshah, Kuen-Song Lin, Abrar Hussain, Jamshid Hussain

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Liver cancer is a significant global health issue, ranking fifth in incidence and second in mortality. Effective therapeutic strategies are urgently needed to combat this disease, particularly in regions with high prevalence. This study focuses on developing and characterizing fluorescent organometallic frameworks as distinct drug delivery carriers with potential applications in both the treatment and biological imaging of liver cancer. This work introduces two distinct organometallic frameworks: the cake-shaped GQD@NH₂-MIL-125 and the cross-shaped M8U6/FM8U6. The GQD@NH₂-MIL-125 framework is particularly noteworthy for its high fluorescence, making it an effective tool for biological imaging. X-ray diffraction (XRD) analysis revealed specific diffraction peaks at 6.81ᵒ (011), 9.76ᵒ (002), and 11.69ᵒ (121), with an additional significant peak at 26ᵒ (2θ), corresponding to the carbon material. Morphological analysis using Field Emission Scanning Electron Microscopy (FE-SEM), and Transmission Electron Microscopy (TEM) demonstrated that the framework has a front particle size of 680 nm and a side particle size of 55±5 nm. High-resolution TEM (HR-TEM) images confirmed the successful attachment of graphene quantum dots (GQDs) onto the NH2-MIL-125 framework. Fourier-Transform Infrared (FT-IR) spectroscopy identified crucial functional groups within the GQD@NH₂-MIL-125 structure, including O-Ti-O metal bonds within the 500 to 700 cm⁻¹ range, and N-H and C-N bonds at 1,646 cm⁻¹ and 1,164 cm⁻¹, respectively. BET isotherm analysis further revealed a specific surface area of 338.1 m²/g and an average pore size of 46.86 nm. This framework also demonstrated UV-active properties, as identified by UV-visible light spectra, and its photoluminescence (PL) spectra showed an emission peak around 430 nm when excited at 350 nm, indicating its potential as a fluorescent drug delivery carrier. In parallel, the cross-shaped M8U6/FM8U6 frameworks were synthesized and characterized using X-ray diffraction, which identified distinct peaks at 2θ = 7.4 (111), 8.5 (200), 9.2 (002), 10.8 (002), 12.1 (220), 16.7 (103), and 17.1 (400). FE-SEM, HR-TEM, and TEM analyses revealed particle sizes of 350±50 nm for M8U6 and 200±50 nm for FM8U6. These frameworks, synthesized from terephthalic acid (H₂BDC), displayed notable vibrational bonds, such as C=O at 1,650 cm⁻¹, Fe-O in MIL-88 at 520 cm⁻¹, and Zr-O in UIO-66 at 482 cm⁻¹. BET analysis showed specific surface areas of 740.1 m²/g with a pore size of 22.92 nm for M8U6 and 493.9 m²/g with a pore size of 35.44 nm for FM8U6. Extended X-ray Absorption Fine Structure (EXAFS) spectra confirmed the stability of Ti-O bonds in the frameworks, with bond lengths of 2.026 Å for MIL-125, 1.962 Å for NH₂-MIL-125, and 1.817 Å for GQD@NH₂-MIL-125. These findings highlight the potential of these organometallic frameworks for enhanced liver cancer therapy through precise drug delivery and imaging, representing a significant advancement in nanomaterial applications in biomedical science.

Keywords: liver cancer cells, metal organic frameworks, Doxorubicin (DOX), drug release.

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Authors: Kaihong Yu, Tetsui Yamashita, Shigeaki Shingyochi, Kazuo Matsumoto, Makoto Ohta

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During cardiac ablation, high power delivery for deeper lesion formation is limited by electrode-tissue interface overheating which can cause serious complications such as thrombus. To prevent this overheating, temperature control and open irrigation are often used. In temperature control, radiofrequency generator is adjusted to deliver the maximum output power, which maintains the electrode temperature at a target temperature (commonly 55°C or 60°C). Then the electrode-tissue interface temperature is also limited. The electrode temperature is a result of heating from the contacted tissue and cooling from the surrounding blood. Because the cooling from blood is decreased under conditions of low blood flow, the generator needs to decrease the output power. Thus, temperature control cannot deliver high power under conditions of low blood flow. In open irrigation, saline in room temperature is flushed through the holes arranged in the electrode. The electrode-tissue interface is cooled by the sufficient environmental cooling. And high power delivery can also be done under conditions of low blood flow. However, a large amount of saline infusions (approximately 1500 ml) during irrigation can cause other serious complication. When open irrigation cannot be used under conditions of low blood flow, a new overheating prevention may be required. The authors have proposed a new electrode cooling method by making the catheter vibrating. The previous work has introduced that the vibration can make a cooling effect on electrode, which may result form that the vibration could increase the flow velocity around the catheter. The previous work has also proved that increasing vibration frequency can increase the cooling by vibration. However, the effect of the vibration amplitude is still unknown. Thus, the present study investigated the effect of vibration amplitude on tissue temperature and lesion size. An agar phantom model was used as a tissue-equivalent material for measuring tissue temperature. Thermocouples were inserted into the agar to measure the internal temperature. Porcine myocardium was used for lesion size measurement. A normal ablation catheter was set perpendicular to the tissue (agar or porcine myocardium) with 10 gf contact force in 37°C saline without flow. Vibration amplitude of ± 0.5, ± 0.75, and ± 1.0 mm with a constant frequency (31 Hz or 63) was used. A temperature control protocol (45°C for agar phantom, 60°C for porcine myocardium) was used for the radiofrequency applications. The larger amplitude shows the larger lesion sizes. And the higher tissue temperatures in agar phantom are also shown with the higher amplitude. With a same frequency, the larger amplitude has the higher vibrating speed. And the higher vibrating speed will increase the flow velocity around the electrode more, which leads to a larger electrode temperature decrease. To maintain the electrode at the target temperature, ablator has to increase the output power. With the higher output power in the same duration, the released energy also increases. Consequently, the tissue temperature will be increased and lead to larger lesion sizes.

Keywords: cardiac ablation, electrode cooling, lesion size, tissue temperature

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Authors: M. Kamimukai, M. Bhattarai, B. B. Rana, K. Maeda, H. B. Kc, T. Kawano, M. Murai

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Most of the aged people older than 70 have difficulty in chewing and swallowing more or less. According to magnitude of this difficulty, gruel, “nanhan” (semi-soft rice) and ordinary cooked rice are served in general, particularly in sanatoriums and homes for old people in Japan. Nanhan is the name of a cooked rice used in Japan, having softness intermediate between gruel and ordinary cooked rice, which is boiled with intermediate amount of water between those of the latter two kinds of cooked rice. In the present study, nanhan was made in the rate of 240g of water to 100g of milled rice with an electric rice cooker. Murai developed a high amylose-content and high-yielding elite line ‘Murai 79’. Sensory eating-quality test was performed for nanhan and ordinary cooked rice of Murai 79 and the standard variety ‘Hinohikari’ which is a high eating-quality variety representative in southern Japan. Panelists (6 to 14 persons) scored each cooked rice in six items viz. taste, stickiness, hardness, flavor, external appearance and overall evaluation. Grading (-3 ~ +3) in each trait was performed, regarding the value of the standard variety Hinohikari as 0. Paddy rice produced in a farmer’s field in 2013 and 2014 and in an experimental field of Kochi University in 2015 and 2016 were used for the sensory test. According to results of the sensory eating-quality test for nanhan, Murai 79 is higher in overall evaluation than Hinohikari in the four years. The former was less sticky than the latter in the four years, but the former was statistically significantly harder than the latter throughout the four years. In external appearance, the former was significantly higher than the latter in the four years. In the taste, the former was significantly higher than the latter in 2014, but significant difference was not noticed between them in the other three years. There were no significant differences throughout the four years in flavor. Regarding amylose content, Murai 79 is higher by 3.7 and 5.7% than Hinohikari in 2015 and 2016, respectively. As for protein content, Murai 79 was higher than Hinohikari in 2015, but the former was lower than the latter in 2016. Consequently, the nanhan of Murai 79 was harder and less sticky, keeping the shape of grains as compared with that of Hinohikari, which may be due to its higher amylose content. Hence, the nanhan of Murai 79 may be recognized as grains more easily in a human mouth, which could make easier the continuous performance of mastication and deglutition particularly in aged persons. Regarding ordinary cooked rice, Murai 79 was similar to or higher in both overall evaluation and external appearance as compared with Hinohikari, despite its higher hardness and lower stickiness. Additionally, Murai 79 had brown-rice yield of 1.55 times as compared with Hinohikari, suggesting that it would enable to supply inexpensive rice for making nanhan with high quality particularly for aged people in Japan.

Keywords: high-amylose content, high-yielding rice line, nanhan, nursing care food, sensory eating quality test

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Authors: Nadarajah I. Ramesh

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Much of the research on stochastic point process models for rainfall has focused on Poisson cluster models constructed from either the Neyman-Scott or Bartlett-Lewis processes. The doubly stochastic Poisson process provides a rich class of point process models, especially for fine-scale rainfall modelling. This paper provides an account of recent development on this topic and presents the results based on some of the fine-scale rainfall models constructed from this class of stochastic point processes. Amongst the literature on stochastic models for rainfall, greater emphasis has been placed on modelling rainfall data recorded at hourly or daily aggregation levels. Stochastic models for sub-hourly rainfall are equally important, as there is a need to reproduce rainfall time series at fine temporal resolutions in some hydrological applications. For example, the study of climate change impacts on hydrology and water management initiatives requires the availability of data at fine temporal resolutions. One approach to generating such rainfall data relies on the combination of an hourly stochastic rainfall simulator, together with a disaggregator making use of downscaling techniques. Recent work on this topic adopted a different approach by developing specialist stochastic point process models for fine-scale rainfall aimed at generating synthetic precipitation time series directly from the proposed stochastic model. One strand of this approach focused on developing a class of doubly stochastic Poisson process (DSPP) models for fine-scale rainfall to analyse data collected in the form of rainfall bucket tip time series. In this context, the arrival pattern of rain gauge bucket tip times N(t) is viewed as a DSPP whose rate of occurrence varies according to an unobserved finite state irreducible Markov process X(t). Since the likelihood function of this process can be obtained, by conditioning on the underlying Markov process X(t), the models were fitted with maximum likelihood methods. The proposed models were applied directly to the raw data collected by tipping-bucket rain gauges, thus avoiding the need to convert tip-times to rainfall depths prior to fitting the models. One advantage of this approach was that the use of maximum likelihood methods enables a more straightforward estimation of parameter uncertainty and comparison of sub-models of interest. Another strand of this approach employed the DSPP model for the arrivals of rain cells and attached a pulse or a cluster of pulses to each rain cell. Different mechanisms for the pattern of the pulse process were used to construct variants of this model. We present the results of these models when they were fitted to hourly and sub-hourly rainfall data. The results of our analysis suggest that the proposed class of stochastic models is capable of reproducing the fine-scale structure of the rainfall process, and hence provides a useful tool in hydrological modelling.

Keywords: fine-scale rainfall, maximum likelihood, point process, stochastic model

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Authors: Demet Devrimsel Dogan, Ecem Deniz Kirkpantur, Muharrem Dogan, Ahmet Aykut, Ebru Unal Akoglu, Ozge Ecmel Onur

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Introduction: Median Arcuate Ligament Syndrome (MALS) is a rare cause of chronic abdominal pain due to external compression of the celiac trunk by a fibrous arch that unites diaphragmatic crura on each side of the aortic hiatus. While 10-24% of the population may suffer from compression of celiac trunk, it rarely causes patients to develop symptoms. The typical clinical triad of symptoms includes postprandial epigastric pain, weight loss and vomiting. The diagnosis can be made using thin section multi-detector computed tomography (CT) scans which delineate the ligament and the compressed vessel. The treatment of MALS is aimed at relieving the compression of the celiac artery to restore adequate blood flow through the vessel and neurolysis to address chronic pain. Case: A 68-year-old male presented to our clinic with acute postprandial epigastric pain. This was patients’ first attack, and the pain was the worst pain of his life. The patient did not have any other symptoms like nausea, vomiting, chest pain or dyspnea. In his medical history, the patient has had an ischemic cerebrovascular stroke 5 years ago which he recovered with no sequel, and he was using 75 mg clopidogrel and 100 mg acetylsalicylic acid. He was not using any other medication and did not have a story of cardiovascular disease. His vital signs were stable (BP:113/72 mmHg, Spo2:97, temperature:36.3°C, HR:90/bpm). In his electrocardiogram, there was ST depression in leads II, III and AVF. In his physical examination, there was only epigastric tenderness, other system examinations were normal. Physical examination through his upper gastrointestinal system showed no bleeding. His laboratory results were as follows: creatinine:1.26 mg/dL, AST:42 U/L, ALT:17 U/L, amylase:78 U/L, lipase:26 U/L, troponin:10.3 pg/ml, WBC:28.9 K/uL, Hgb:12.7 gr/dL, Plt:335 K/uL. His serial high-sensitive troponin levels were also within normal limits, his echocardiography showed no segmental wall motion abnormalities, an acute myocardial infarction was excluded. In his abdominal ultrasound, no pathology was founded. Contrast-enhanced abdominal CT and CT angiography reported ‘thickened diaphragmatic cruras are compressing and stenosing truncus celiacus superior, this is likely compatible with MALS’. The patient was consulted to general surgery, and they admitted the patient for laparoscopic ligament release. Results: MALS is a syndrome that causes postprandial pain, nausea and vomiting as its most common symptoms. Affected patients are normally young, slim women between the ages of 30 and 50 who have undergone extensive examinations to find the source of their symptoms. To diagnose MALS, other underlying pathologies should initially be excluded. The gold standard is aortic angiography. Although diagnosis and treatment of MALS are unclear, symptom resolution has been achieved with multiple surgical modalities, including open, laparoscopic or robotic ligament release as well as celiac ganglionectomy, which often requires celiac artery revascularisation.

Keywords: differential diagnosis, epigastric pain, median arcuate ligament syndrome, celiac trunk

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Authors: Nidhi Prabha

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Transportation as a sector is one of the most significant infrastructural elements of the ‘urban.' The distinctness of an urban life in a city is marked by the dynamic movements that it enables within the city-space. Therefore it is important to study the public-transport systems that enable and foster mobility which characterizes the urban. It is also crucial to underscore the way one is examining the urban transport systems - either as an infrastructural unit in a strict physical-structural sense or as a structural unit which acts as a prism refracting multiple experiences depending on the location of the ‘commuter.' In the proposed paper, the attempt is to uncover and investigate the assumption of the neuter-commuter by looking at urban transportation in the secondary sense i.e. as a structural unit which is experienced differently by different kinds of commuters, thus making transportation deeply distributed with various social structures and locations like class or gender which map onto the transport systems. To this end, the public-transit systems operating in Urban Delhi i.e. the Delhi Metros and the Delhi Transport Corporation run public-buses are looked at as case studies. The study is premised on the knowledge and data gained from both primary and secondary sources. Primary sources include data and knowledge collected from fieldwork, the methodology for which has ranged from adopting ‘mixed-methods’ which is ‘Qualitative-then-Quantitative’ as well as borrowing ethnographic techniques. Apart from fieldwork, other primary sources looked at including Annual Reports and policy documents of the Delhi Metro Rail Corporation (DMRC) and the Delhi Transport Corporation (DTC), Union and Delhi budgets, Economic Survey of Delhi, press releases, etc. Secondary sources include the vast array of literature available on the critical nodes that inform the research like gender, transport geographies, urban-space, etc. The study indicates a deeply-distributed urban transport system wherein the various social-structural locations or different kinds of commuters map onto the way these different commuters experience mobility or movement within the city space. Mobility or movement, therefore, becomes gendered or has class-based ramifications. The neuter-commuter assumption is thus challenged. Such an understanding enables us to challenge the anonymity which the ‘urban’ otherwise claims it provides over the rural. The rural is opposed to the urban wherein urban ushers a modern way of life, breaking ties of traditional social identities. A careful study of the transport systems through the traveling patterns and choices of the commuters, however, indicate that this does not hold true as even the same ‘public-space’ of the transport systems allocates different places to different kinds of commuters. The central argument made though the research done is therefore that infrastructure like urban-transport-systems has to be studied and examined as seen beyond just a physical structure. The various experiences of daily mobility of different kinds of commuters have to be taken into account in order to design and plan more inclusive transport systems.

Keywords: gender, infrastructure, mobility, urban-transport-systems

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Authors: Yumei Han, Naiqing Song, Xiaoping Yang, Yuping Han

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This study explores the conceptualization of key competencies that children are expected to develop in three year preschools (age 3-6) and the assessment practices of such key competencies in China. Assessment of children development has been put into the central place of early childhood education quality evaluation system in China. In the context of students key competencies development centered education reform in China, defining and selecting key competencies of children in preschools are of great significance in that they would lay a solid foundation for children’s lifelong learning path, and they would lead to curriculum and instruction reform, teacher development reform as well as quality evaluation reform in the early childhood education area. Based on sense making theory and framework, this study adopted multiple stakeholders’ (early childhood educators, parents, evaluation administrators, scholars in the early childhood education field) perspectives and grass root voices to conceptualize and operationalize key competencies for children in preschools in Southwest China. On the ground of children development theories, Chinese and international literature related to children development and key competencies, and key competencies frameworks by UNESCO, OECD and other nations, the authors designed a two-phase sequential mixed method study to address three main questions: (a) How is early childhood key competency defined or labeled from literature and from different stakeholders’ views? (b) Based on the definitions explicated in the literature and the surveys on different stakeholders, what domains and components are regarded to constitute the key competency framework of children in three-year preschools in China? (c) How have early childhood key competencies been assessed and measured, and how such assessment and measurement contribute to enhancing early childhood development quality? On the first phase, a series of focus group surveys were conducted among different types of stakeholders around the research questions. Moreover, on the second phase, based on the coding of the participants’ answers, together with literature synthesis findings, a questionnaire survey was designed and conducted to select most commonly expected components of preschool children’s key competencies. Semi-structured open questions were also included in the questionnaire for the participants to add on competencies beyond the checklist. Rudimentary findings show agreeable concerns on the significance and necessity of conceptualization and assessment of key competencies for children in preschools, and a key competencies framework composed of 7 domains and 25 indicators was constructed. Meanwhile, the findings also show issues in the current assessment practices of children’s competencies, such as lack of effective assessment tools, lack of teacher capacity in applying the tools to evaluating children and advancing children development accordingly. Finally, the authors put forth suggestions and implications for China and international communities in terms of restructuring early childhood key competencies framework, and promoting child development centered reform in early childhood education quality evaluation and development.

Keywords: assessment, conceptualization, early childhood education quality in China, key competencies

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Authors: Shahira Mahmoud Yacout

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Writing is an essential skill in many vocational, academic environments, and notably workplaces, yet many students perceive writing as being something tiring and boring or maybe a “waste of time”. Studies in the field of foreign languages related this fact might be due to the lack of connection between what is learned in the university and what students come to encounter in real life situations”. Arabic learners felt they needed more language exposure to the context of their future professions. With this idea in mind, Scenario based learning (SBL) is reported to be an educational approach to motivate, engage and stimulate students’ interest and to achieve the desired writing learning outcomes. In addition, researchers suggested Scenario based learning (SBL)as an instructional approach that develops and enhances students skills through developing higher order thinking skills and active learning. It is a subset of problem-based learning and case-based learning. The approach focuses on authentic rhetorical framing reflecting writing tasks in real life situations. It works successfully when used to simulate real-world practices, providing context that reflects the types of situations professionals respond to in writing. It was claimed that using realistic scenarios customized to the course’s learning objectives as it bridged the gap for students between theory and application. Within this context, it is thought that scenario-based learning is an important approach to enhance the learners’ writing skills and to reflect meaningful learning within authentic contexts. As an Arabicforeign language instructor, it was noticed that students find difficulties in adapting writing styles to authentic writing contexts and addressing different audiences and purposes. This idea is supported by studieswho claimed that AFL students faced difficulties with transferring writing skills to situations outside of the classroom context. In addition, it was observed that some of the Arabic textbooks for teaching Arabic as a foreign language lacked topics that initiated higher order thinking skills and stimulated the learners to understand the setting, and created messages appropriate to different audiences, context, and purposes. The goals of this study are to 1)provide a rational for using scenario-based learning approach to improveAFL learners in writing skills, 2) demonstrate how to design/ implement a scenario-based learning technique aligned with the writing course objectives,3) demonstrate samples of scenario-based approach implemented in AFL writing class, and 4)emphasis the role of peer-review along with the instructor’s feedback, in the process of developing the writing skill. Finally, this presentation highlighted and emphasized the importance of using the scenario-based learning approach in writing as a means to mirror students’ real-life situations and engage them in planning, monitoring, and problem solving. This approach helped in making writing an enjoyable experience and clearly useful to students’ future professional careers.

Keywords: meaningful learning, real life contexts, scenario based learning, writing skill

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Authors: Al Huuskonen, Clio Lake, K. M. Naude, Polina Petlitsyna, Sorsha Henning, Julia Wimmers-Klick

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This project presents the outcomes of a community-based participatory action initiative aimed at advocating for equitable healthcare and human rights for trans, two-spirit, and gender-diverse individuals, building upon the University of British Columbia (UBC) Trans Coalition's ongoing efforts. Participatory Action Research (PAR) was chosen as the research method with the goal of improving trans rights on the UBC campus, particularly regarding equitable access to healthcare. PAR involves active community contribution throughout the research process, which in this case was done by way of liaising with student resource groups and advocacy leaders. The goals of this project were as follows: a) identify gaps in gender-affirming healthcare for UBC students by consulting the community and collaborating with UBC services, b) develop an information package outlining provincial and university-based health insurance for gender-affirming care (including hormone therapy and surgeries), FAQs, and resources for UBC's trans students, c) make this package available to UBC students and other national transgender advocacy organizations. The initiative successfully expanded the UBC AMS Student Health and Dental Plan to include gender-affirming procedural coverage, developed a care access guide for students, and advocated for improved health records inclusivity, mechanisms for trans students to report negative care experiences, and increased access to gender-affirming primary care through the on-campus health clinic. Collaboration with other universities' pride organizations and Trans Care BC yielded positive outcomes through broader coalition building and resource sharing. Ongoing efforts are underway to update provincial policies, particularly through expanding coverage under fair pharma care and addressing the compounding effects of the primary care crisis for trans individuals. The project's tangible results include improved trans rights on campus, especially in terms of healthcare access. Expanding healthcare coverage through student care benefits thousands of students, making the ability to undergo important affirming procedures more affordable. Providing students with information on extended coverage options and communication with their doctors further removes barriers to care and positively impacts student wellbeing. This initiative demonstrates the effectiveness of community-based participatory action in advancing equitable healthcare for trans and gender-diverse individuals and serves as a model for other institutions and organizations striving to promote inclusivity and advocate for marginalized populations' rights.

Keywords: equitable healthcare, trans and gender-diverse individuals, inclusivity, participatory action research project

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Authors: Saimir Cenameri, Arjana Tereziu, Kastriot Dallaku

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Introduction: Intra-uterine death is a common problem in obstetrical practice, and can lead to complications if left to resolve spontaneously. The cervix is unprepared, making inducing of labor difficult. Misoprostol is a synthetic prostaglandin E1 analogue, inexpensive, and is presented valid thanks to its ability to bring about changes in the cervix that lead to the induction of uterine contractions. Misoprostol is quickly absorbed when taken orally, resulting in high initial peak serum concentrations compared with the vaginal route. The vaginal misoprostol peak serum concentration is not as high and demonstrates a more gradual serum concentration decline. This is associated with many benefits for the patient; fast induction of labor; smaller doses; and fewer side effects (dose-depended). Mostly it has been used the regime of 50 μg/4 hour, with a high percentage of success and limited side effects. Objective: Evaluation of the efficiency of the use of oral and vaginal misoprostol in inducing labor, and comparing it with its use not by a previously defined protocol. Methods: Participants in this study included patients at U.H.O.G. 'Koco Gliozheni', Tirana from April 2004-July 2006, presenting with an indication for inducing labor in the third trimester for pregnancy termination. A total of 37 patients were randomly admitted for birth inducing activity, according to protocol (26), oral or vaginal protocol (10 vs. 16), and a control group (11), not subject to the protocol, was created. Oral or vaginal misoprostol was administered at a dose of 50 μg/4 h, while the fourth group participants were treated individually by the members of the medical staff. The main result of interest was the time between induction of labor to birth. Kruskal-Wallis test was used to compare the average age, parity, women weight, gestational age, Bishop's score, the size of the uterus and weight of the fetus between the four groups in the study. The Fisher exact test was used to compare day-stay and causes in the four groups. Mann-Whitney test was used to compare the time of the expulsion and the number of doses between oral and vaginal group. For all statistical tests used, the value of P ≤ 0.05 was considered statistically significant. Results: The four groups were comparable with regard to woman age and weight, parity, abortion indication, Bishop's score, fetal weight and the gestational age. There was significant difference in the percentage of deliveries within 24 hours. The average time from induction to birth per route (vaginal, oral, according to protocol and not according to the protocol) was respectively; 10.43h; 21.10h; 15.77h, 21.57h. There was no difference in maternal complications in groups. Conclusions: Use of vaginal misoprostol for inducing labor in the third trimester for termination of pregnancy appears to be more effective than the oral route, and even more to uses not according to the protocols approved before, where complications are greater and unjustified.

Keywords: inducing labor, misoprostol, pregnancy termination, third trimester

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Authors: Jo Mitchell, Daniel Johnson

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MindMax is a digital community and learning platform built to maximise the wellbeing and resilience of AFL Players and Australian men. The MindMax application engages men, via their existing connection with sport and video games, in a range of wellbeing ideas, stories and actions, because we believe fit minds, kick goals. MindMax is an AFL Players Association led project, supported by a Movember Foundation grant, to improve the mental health of Australian males aged between 16-35 years. The key engagement and delivery strategy for the project was digital technology, sport (AFL) and video games, underpinned by evidenced based wellbeing science. The project commenced April 2015, and the expected completion date is March 2017. This paper describes the conceptual model underpinning product development, including progress, key learnings and challenges, as well as the research agenda. Evaluation of the MindMax project is a multi-pronged approach of qualitative and quantitative methods, including participatory design workshops, online reference groups, longitudinal survey methods, a naturalistic efficacy trial and evaluation of the social and economic return on investment. MindMax is focused on the wellness pathway and maximising our mind's capacity for fitness by sharing and promoting evidence-based actions that support this. A range of these ideas (from ACT, mindfulness and positive psychology) are already being implemented in AFL programs and services, mostly in face-to-face formats, with strong engagement by players. Player's experience features strongly as part of the product content. Wellbeing science is a discipline of psychology that explores what helps individuals and communities to flourish in life. Rather than ask questions about illness and poor functioning, wellbeing scientists and practitioners ask questions about wellness and optimal functioning. While illness and wellness are related, they operate as separate constructs and as such can be influenced through different pathways. The essential idea was to take the evidence-based wellbeing science around building psychological fitness to the places and spaces that men already frequent, namely sport and video games. There are 800 current senior AFL players, 5000+ past players, and 11 million boys and men that are interested in the lives of AFL Players; what they think and do to be their best both on and off field. AFL Players are also keen video gamers – using games as one way to de-stress, connect and build wellbeing. There are 9.5 million active gamers in Australia with 93% of households having a device for playing games. Video games in MindMax will be used as an engagement and learning tool. Gamers (including AFL players) can also share their personal experience of how games help build their mental fitness. Currently available games (i.e., we are not in the game creation business) will also be used to motivate and connect MindMax participants. The MindMax model is built with replication by other sport codes (e.g., Cricket) in mind. It is intended to not only support our current crop of athletes but also the community that surrounds them, so they can maximise their capacity for health and wellbeing.

Keywords: Australian football league, digital application, positive psychology, wellbeing

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Authors: Carine Platat, Fatima Qshadi, Ghofran Kayed, Nour Hussein, Amjad Jarrar, Habiba Ali

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Nowadays, smartphones are very popular. They are offering a variety of easy-to-use and free applications among which step counters and fitness tests. The number of users is huge making of such applications a potentially efficient new strategy to encourage people to become more active. Nonetheless, data on their reliability and validity are very scarce and when available, they are often negative and contradictory. Besides, weight status, which is likely to introduce a bias in the physical activity assessment, was not often considered. Hence, the use of these applications as motivational tool, assessment tool and in research is questionable. PACER is one of the free step counters application. Even though it is one of the best rated free application by users, it has never been tested for reliability and validity. Prior any use of PACER, this remains to be investigated. The objective of this work is to investigate the reliability and validity of the smartphone application PACER in measuring the number of steps and in assessing the cardiorespiratory fitness by the 6 minutes walking test. 20 overweight or obese students (10 male and 10 female) were recruited at the United Arab Emirate University, aged between 18 and 25 years old. Reliability and validity were tested in real life conditions and in controlled conditions by using a treadmill. Test-retest experiments were done with PACER on 2 days separated by a week in real life conditions (24 hours each time) and in controlled conditions (30 minutes on treadmill, 3km/h). Validity was tested against the pedometer OMRON in the same conditions. During treadmill test, video was recorded and steps numbers were compared between PACER, pedometer and video. The validity of PACER in estimating the cardiorespiratory fitness (VO2max) as part of the 6 minutes walking test (6MWT) was studied against the 20m shuttle running test. Reliability was studied by calculating intraclass correlation coefficients (ICC), 95% confidence interval (95%CI) and by Bland-Altman plots. Validity was studied by calculating Spearman correlation coefficient (rho) and Bland-Altman plots. PACER reliability was good in both male and female in real life conditions (p≤10-3) but only in female in controlled conditions (p=0.01). PACER was valid against OMRON pedometer in male and female in real life conditions (rho=0.94, p≤10-3 ; rho=0.64, p=0.01, in male and female respectively). In controlled conditions, PACER was not valid against pedometer. But, PACER was valid against video in female (rho=0.72, p≤10-3). PACER was valid against the shuttle run test in male and female (rho-=0.66, p=0.01 ; rho=0.51, p=0.04) to estimate VO2max. This study provides data on the reliability and viability of PACER in overweight or obese male and female young adults. Globally, PACER was shown as reliable and valid in real life conditions in overweight or obese male and female to count steps and assess fitness. This supports the use of PACER to assess and promote physical activity in clinical follow-up and community interventions.

Keywords: smartphone application, pacer, reliability, validity, steps, fitness, physical activity

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Authors: T. Poyai, P. Painmanakul, N. Chawaloesphonsiya, P. Dhanasin, C. Getwech, P. Wattana

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Drilling is a key activity in oil and gas exploration and production. Drilling always requires the use of drilling mud for lubricating the drill bit and controlling the subsurface pressure. As drilling proceeds, a considerable amount of cuttings or rock fragments is generated. In general, water or Water Based Mud (WBM) serves as drilling fluid for the top hole section. The cuttings generated from this section is non-hazardous and normally applied as fill materials. On the other hand, drilling the bottom hole to reservoir section uses Synthetic Based Mud (SBM) of which synthetic oils are composed. The bottom-hole cuttings, SBM cuttings, is regarded as a hazardous waste, in accordance with the government regulations, due to the presence of hydrocarbons. Currently, the SBM cuttings are disposed of as an alternative fuel and raw material in cement kiln. Instead of burning, this work aims to propose an alternative for drill cuttings management under two ultimate goals: (1) reduction of hazardous waste volume; and (2) making use of the cleaned cuttings. Soil washing was selected as the major treatment process. The physiochemical properties of drill cuttings were analyzed, such as size fraction, pH, moisture content, and hydrocarbons. The particle size of cuttings was analyzed via light scattering method. Oil present in cuttings was quantified in terms of total petroleum hydrocarbon (TPH) through gas chromatography equipped with flame ionization detector (GC-FID). Other components were measured by the standard methods for soil analysis. Effects of different washing agents, liquid-to-solid (L/S) ratio, washing time, mixing speed, rinse-to-solid (R/S) ratio, and rinsing time were also evaluated. It was found that drill cuttings held the electrical conductivity of 3.84 dS/m, pH of 9.1, and moisture content of 7.5%. The TPH in cuttings existed in the diesel range with the concentration ranging from 20,000 to 30,000 mg/kg dry cuttings. A majority of cuttings particles held a mean diameter of 50 µm, which represented silt fraction. The results also suggested that a green solvent was considered most promising for cuttings treatment regarding occupational health, safety, and environmental benefits. The optimal washing conditions were obtained at L/S of 5, washing time of 15 min, mixing speed of 60 rpm, R/S of 10, and rinsing time of 1 min. After washing process, three fractions including clean cuttings, spent solvent, and wastewater were considered and provided with recommendations. The residual TPH less than 5,000 mg/kg was detected in clean cuttings. The treated cuttings can be then used for various purposes. The spent solvent held the calorific value of higher than 3,000 cal/g, which can be used as an alternative fuel. Otherwise, the recovery of the used solvent can be conducted using distillation or chromatography techniques. Finally, the generated wastewater can be combined with the produced water and simultaneously managed by re-injection into the reservoir.

Keywords: drill cuttings, green solvent, soil washing, total petroleum hydrocarbon (TPH)

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Authors: Simran Baweja, Bhavika Kalal, Surajit Maity

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Photoinduced tautomerization reactions have been the centre of attention among the scientific community over the past several decades because of their significance in various biological systems. 7-azaindole (7AI) is considered a model system for DNA base pairing and to understand the role of such tautomerization reactions in mutations. To the best of our knowledge, extensive studies have been carried out on 7-azaindole and its solvent clusters exhibiting proton/ hydrogen transfer in both solution as well as gas phases. Derivatives of the above molecule, like 2,7- and 2,6-diazaindoles are proposed to have even better photophysical properties due to the presence of -aza group on the 2nd position. However, there are studies in the solution phase that suggest the relevance of these molecules, but there are no experimental studies reported in the gas phase yet. In our current investigation, we present the first gas phase spectroscopic data of 2,7-diazaindole (2,7-DAI) and its solvent cluster (2,7-DAI-H2O). In this, we have employed state-of-the-art laser spectroscopic methods such as fluorescence excitation (LIF), dispersed fluorescence (DF), resonant two-photon ionization-time of flight mass spectrometry (2C-R2PI), photoionization efficiency spectroscopy (PIE), IR-UV double resonance spectroscopy, i.e., fluorescence-dip infrared spectroscopy (FDIR) and resonant ion-dip infrared spectroscopy (IDIR) to understand the electronic structure of the molecule. The origin band corresponding to the S1 ← S0 transition of the bare 2,7-DAI is found to be positioned at 33910 cm-1, whereas the origin band corresponding to S1 ← S0 transition of the 2,7-DAI-H2O is positioned at 33074 cm-1. The red-shifted transition in the case of solvent cluster suggests the enhanced feasibility of excited state hydrogen/ proton transfer. The ionization potential for the 2,7-DAI molecule is found to be 8.92 eV which is significantly higher than the previously reported 7AI (8.11 eV) molecule, making it a comparatively complex molecule to study. The ionization potential is reduced by 0.14 eV in the case of 2,7-DAI-H2O (8.78 eV) cluster compared to that of 2,7-DAI. Moreover, on comparison with the available literature values of 7AI, we found the origin band of 2,7-DAI and 2,7-DAI-H2O to be red-shifted by -729 and -280 cm-1 respectively. The ground and excited state N-H stretching frequencies of the 27DAI molecule were determined using fluorescence-dip infrared spectra (FDIR) and resonant ion dip infrared spectroscopy (IDIR), obtained at 3523 and 3467 cm-1, respectively. The lower value of vNH in the electronically excited state of 27DAI implies the higher acidity of the group compared to the ground state. Moreover, we have done extensive computational analysis, which suggests that the energy barrier in the excited state reduces significantly as we increase the number of catalytic solvent molecules (S= H2O, NH3) as well as the polarity of solvent molecules. We found that the ammonia molecule is a better candidate for hydrogen transfer compared to water because of its higher gas-phase basicity. Further studies are underway to understand the excited state dynamics and photochemistry of such N-rich chromophores.

Keywords: excited state hydrogen transfer, supersonic expansion, gas phase spectroscopy, IR-UV double resonance spectroscopy, laser induced fluorescence, photoionization efficiency spectroscopy

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Authors: Mohammad Ehsani, Iman Zarei, Soudabeh Moazemigoudarzi

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The aim of this study is to determine Pro-Environmental Behavioral Intention of Mountain Hikers to the Theory of Planned Behavior. According to many researchers nature-based recreation activities play a significant role in the tourism industry and have provided myriad opportunities for the protection of natural areas. It is essential to investigate individuals' behavior during such activities to avoid further damage to precious and dwindling natural resources. This study develops a robust model that provides a comprehensive understanding of the formation of pro-environmental behavioral intentions among climbers of Mount Damavand National Park in Iran. To this end, we combined the theory of planned behavior (TPB), value-belief-norm theory (VBN), and a hierarchical model of leisure constraints to predict individuals’ pro-environmental hiking behavior during outdoor recreation. It was used structural equation modeling to test the theoretical framework. A sample of 787 climbers was analyzed. Among the theory of planned behavior variables, perceived behavioral control showed the strongest association with behavioral intention (β = .57). This relationship indicates that if people feel they can have fewer negative impacts on national resources while hiking, it will result in more environmentally acceptable behavior. Subjective norms had a moderate positive impact on behavioral intention, indicating the importance of other people on the individual's behavior. Attitude had a small positive effect on intention. Ecological worldview positively influenced attitude and personal belief. Personal belief (awareness of consequences and ascribed responsibility) showed a positive association with TPB variables. Although the data showed a high average score in awareness of consequences (mean = 4.219 out of 5), evidence from Damavand Mount shows that there are many environmental issues that need addressing (e.g., vast amounts of garbage). National park managers need to make sure that their solutions result in awareness about proenvironmental behavior (PEB). Findings showed that negative relationship between constraints and all TPB predictors. Providing proper restrooms and parking spaces in campgrounds, strategies controlling limiting capacity and solutions for removing waste from high altitudes are helpful to decrease the negative impact of structural constraints. In order to address intrapersonal constraints, managers should provide opportunities to interest individuals in environmental activities, such as environmental celebrations or making documentaries about environmental issues. Moreover, promoting a culture of environmental protection in the Damavand Mount area would reduce interpersonal constraints. Overall, the proposed model improved the explanatory power of the TPB by predicting 64.7% of intention compared to the original TPB that accounted for 63.8% of the variance in intention.

Keywords: theory of planned behavior, pro-environmental behavior, national park, constraints

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Authors: Yi Li, Rui Lu, Lianjun Wang

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With the rapid development of chemical industry, the consumption of volatile organic compounds (VOCs) has increased extensively. In the process of VOCs production and application, plenty of them have been transferred to environment. As a result, it has led to pollution problems not only in soil and ground water but also to human beings. Thus, it is important to develop a sensitive and cost-effective analytical method for trace VOCs detection in environment. Surface-enhanced Raman Spectroscopy (SERS), as one of the most sensitive optical analytical technique with rapid response, pinpoint accuracy and noninvasive detection, has been widely used for ultratrace analysis. Based on the plasmon resonance on the nanoscale metallic surface, SERS technology can even detect single molecule due to abundant nanogaps (i.e. 'hot spots') on the nanosubstrate. In this work, a self-supported flexible silver nitrate (AgNO3)/ethylene-propylene copolymer (EPM) hybrid nanofibers was fabricated by electrospinning. After an in-situ chemical reduction using ice-cold sodium borohydride as reduction agent, numerous silver nanoparticles were formed on the nanofiber surface. By adjusting the reduction time and AgNO3 content, the morphology and dimension of silver nanoparticles could be controlled. According to the principles of solid-phase extraction, the hydrophobic substance is more likely to partition into the hydrophobic EPM membrane in an aqueous environment while water and other polar components are excluded from the analytes. By the enrichment of EPM fibers, the number of hydrophobic molecules located on the 'hot spots' generated from criss-crossed nanofibers is greatly increased, which further enhances SERS signal intensity. The as-prepared Ag/EPM hybrid nanofibers were first employed to detect common SERS probe molecule (p-aminothiophenol) with the detection limit down to 10-12 M, which demonstrated an excellent SERS performance. To further study the application of the fabricated substrate for monitoring hydrophobic substance in water, several typical VOCs, such as benzene, toluene and p-xylene, were selected as model compounds. The results showed that the characteristic peaks of these target analytes in the mixed aqueous solution could be distinguished even at a concentration of 10-6 M after multi-peaks gaussian fitting process, including C-H bending (850 cm-1), C-C ring stretching (1581 cm-1, 1600 cm-1) of benzene, C-H bending (844 cm-1 ,1151 cm-1), C-C ring stretching (1001 cm-1), CH3 bending vibration (1377 cm-1) of toluene, C-H bending (829 cm-1), C-C stretching (1614 cm-1) of p-xylene. The SERS substrate has remarkable advantages which combine the enrichment capacity from EPM and the Raman enhancement of Ag nanoparticles. Meanwhile, the huge specific surface area resulted from electrospinning is benificial to increase the number of adsoption sites and promotes 'hot spots' formation. In summary, this work provides powerful potential in rapid, on-site and accurate detection of trace VOCs using a portable Raman.

Keywords: electrospinning, ethylene-propylene copolymer, silver nanoparticles, SERS, VOCs

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Authors: S. Alina Wang

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A Gibsonian approach is used to understand the existential dimensions of the human ecological niche. Then, this existential-Gibsonian framework is applied to rethinking Hacking’s historical analysis of multiple personality disorder. This research culminates in a generalized account of psychiatric illness from an enactivist lens. In conclusion, reflections on the implications of this account on approaches to psychiatric treatment are mentioned. J.J. Gibson’s theory of affordances centered on affordances of sensorimotor varieties, which guide basic behaviors relative to organisms’ vital needs and physiological capacities (1979). Later theorists, notably Neisser (1988) and Rietveld (2014), expanded on the theory of affordances to account for uniquely human activities relative to the emotional, intersubjective, cultural, and narrative aspects of the human ecological niche. This research shows that these affordances are structured by what Haugeland (1998) calls existential commitments, which draws on Heidegger’s notion of dasein (1927) and Merleau-Ponty’s account of existential freedom (1945). These commitments organize the existential affordances that fill an individual’s environment and guide their thoughts, emotions, and behaviors. This system of a priori existential commitments and a posteriori affordances is called existential enactivism. For humans, affordances do not only elicit motor responses and appear as objects with instrumental significance. Affordances also, and possibly primarily, determine so-called affective and cognitive activities and structure the wide range of kinds (e.g., instrumental, aesthetic, ethical) of significances of objects found in the world. Then existential enactivism is applied to understanding the psychiatric phenomenon of multiple personality disorder (precursor of the current diagnosis of dissociative identity disorder). A reinterpretation of Hacking’s (1998) insights into the history of this particular disorder and his generalizations on the constructed nature of most psychiatric illness is taken on. Enactivist approaches sensitive to existential phenomenology can provide a deeper understanding of these matters. Conceptualizing psychiatric illness as strictly a disorder in the head (whether parsed as a disorder of brain chemicals or meaning-making capacities encoded in psychological modules) is incomplete. Rather, psychiatric illness must also be understood as a disorder in the world, or in the interconnected networks of existential affordances that regulate one’s emotional, intersubjective, and narrative capacities. All of this suggests that an adequate account of psychiatric illness must involve (1) the affordances that are the sources of existential hindrance, (2) the existential commitments structuring these affordances, and (3) the conditions of these existential commitments. Approaches to treatment of psychiatric illness would be more effective by centering on the interruption of normalized behaviors corresponding to affordances targeted as sources of hindrance, the development of new existential commitments, and the practice of new behaviors that erect affordances relative to these reformed commitments.

Keywords: affordance, enaction, phenomenology, psychiatry, psychopathology

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Authors: Lucas Derks, Christine Beenhakker, Michiel Brandt, Gert Arts, Ruud van Langeveld

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Background: The method Depression in Awareness Space (DAS) is a psychotherapeutic intervention technique based on the principles of spatial cognition and imagination therapy with spatial components. The basic assumptions are: mental space is the primary organizing principle in the mind, and all psychological issues can be treated by first locating and by next relocating the conceptualizations involved. The most clinical experience was gathered over the last 20 years in the area of social issues (with the social panorama model). The latter work led to the conclusion that a mental object (image) gains emotional impact when it is placed more central, closer and higher in the visual field – and vice versa. Changing the locations of mental objects in space thus alters the (socio-) emotional meaning of the relationships. The experience of depression seems always associated with darkness. Psychologists tend to see the link between depression and darkness as a metaphor. However, clinical practice hints to the existence of more literal forms of darkness. Aims: The aim of the method Depression in Awareness Space is to reduce the distress of clients with depression in the clinical counseling practice, as a reliable alternative method of psychological therapy for the treatment of depression. The method Depression in Awareness Space aims at making dark areas smaller, lighter and more transparent in order to identify the problem or the cause of the depression which lies behind the darkness. It was hypothesized that the darkness is a subjective side-effect of the neurological process of repression. After reducing the dark clouds the real problem behind the depression becomes more visible, allowing the client to work on it and in that way reduce their feelings of depression. This makes repression of the issue obsolete. Results: Clients could easily get into their 'sadness' when asked to do so and finding the location of the dark zones proved pretty easy as well. In a recent pilot study with five participants with mild depressive symptoms (measured on two different scales and tested against an untreated control group with similar symptoms), the first results were also very promising. If the mental spatial approach to depression can be proven to be really effective, this would be very good news. The Society of Mental Space Psychology is now looking for sponsoring of an up scaled experiment. Conclusions: For spatial cognition and the research into spatial psychological phenomena, the discovery of dark areas can be a step forward. Beside out of pure scientific interest, it is great to know that this discovery has a clinical implication: when darkness can be connected to depression. Also, darkness seems to be more than metaphorical expression. Progress can be monitored over measurement tools that quantify the level of depressive symptoms and by reviewing the areas of darkness.

Keywords: depression, spatial cognition, spatial imagery, social panorama

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Authors: Hai L. Tran

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Previous research on agenda setting effects has often focused on the top-down influence of the media at the aggregate level, while overlooking the capacity of audience members to select media and content to fit their individual dispositions. The decentralized characteristics of online communication and digital news create more choices and greater user control, thereby enabling each audience member to seek out a unique blend of media sources, issues, and elements of messages and to mix them into a coherent individual picture of the world. This study examines how audiences use media differently depending on their prior dispositions, thereby making sense of the world in ways that are congruent with their preferences and cognitions. The current undertaking is informed by theoretical frameworks from two distinct lines of scholarship. According to the ideological migration hypothesis, individuals choose to live in communities with ideologies like their own to satisfy their need to belong. One tends to move away from Zip codes that are incongruent and toward those that are more aligned with one’s ideological orientation. This geographical division along ideological lines has been documented in social psychology research. As an extension of agenda setting, the agendamelding hypothesis argues that audiences seek out information in attractive media and blend them into a coherent narrative that fits with a common agenda shared by others, who think as they do and communicate with them about issues of public. In other words, individuals, through their media use, identify themselves with a group/community that they want to join. Accordingly, the present study hypothesizes that because ideology plays a role in pushing people toward a physical community that fits their need to belong, it also leads individuals to receive an idiosyncratic blend of media and be influenced by such selective exposure in deciding what issues are more relevant. Consequently, the individualized focus of media choices impacts how audiences perceive political news coverage and what they know about political issues. The research project utilizes recent data from The American Trends Panel survey conducted by Pew Research Center to explore the nuanced nature of agenda setting at the individual level and amid heightened polarization. Hypothesis testing is performed with both nonparametric and parametric procedures, including regression and path analysis. This research attempts to explore the media-public relationship from a bottom-up approach, considering the ability of active audience members to select among media in a larger process that entails agenda setting. It helps encourage agenda-setting scholars to further examine effects at the individual, rather than aggregate, level. In addition to theoretical contributions, the study’s findings are useful for media professionals in building and maintaining relationships with the audience considering changes in market share due to the spread of digital and social media.

Keywords: agenda setting, agendamelding, audience fragmentation, ideological migration, partisanship, polarization

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Authors: Kari Björn

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Introduction of games has expanded the application area of computer-aided learning tools to wide variety of age groups of learners. Serious games engage the learners into a real-world -type of simulation and potentially enrich the learning experience. Institutional background of a Bachelor’s level engineering program in Information and Communication Technology is introduced, with detailed focus on one of its majors, Health Technology. As part of a Customer Oriented Software Application thematic semester, one particular course of “eHealth Business and Solutions” is described and reflected in a gamified framework. Learning a consistent view into vast literature of business management, strategies, marketing and finance in a very limited time enforces selection of topics relevant to the industry. Health Technology is a novel and growing industry with a growing sector in consumer wearable devices and homecare applications. The business sector is attracting new entrepreneurs and impatient investor funds. From engineering education point of view the sector is driven by miniaturizing electronics, sensors and wireless applications. However, the market is highly consumer-driven and usability, safety and data integrity requirements are extremely high. When the same technology is used in analysis or treatment of patients, very strict regulatory measures are enforced. The paper introduces a course structure using gamification as a tool to learn the most essential in a new market: customer value proposition design, followed by a market entry game. Students analyze the existing market size and pricing structure of eHealth web-service market and enter the market as a steering group of their company, competing against the legacy players and with each other. The market is growing but has its rules of demand and supply balance. New products can be developed with an R&D-investment, and targeted to market with unique quality- and price-combinations. Product cost structure can be improved by investing to enhanced production capacity. Investments can be funded optionally by foreign capital. Students make management decisions and face the dynamics of the market competition in form of income statement and balance sheet after each decision cycle. The focus of the learning outcome is to understand customer value creation to be the source of cash flow. The benefit of gamification is to enrich the learning experience on structure and meaning of financial statements. The paper describes the gamification approach and discusses outcomes after two course implementations. Along the case description of learning challenges, some unexpected misconceptions are noted. Improvements of the game or the semi-gamified teaching pedagogy are discussed. The case description serves as an additional support to new game coordinator, as well as helps to improve the method. Overall, the gamified approach has helped to engage engineering student to business studies in an energizing way.

Keywords: engineering education, integrated curriculum, learning experience, learning outcomes

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Authors: Chunyang Miao, Bingxin Li, Shanglong Ning, Christopher J. B. Ford

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While it is challenging to fabricate electronic devices close to atomic dimensions in conventional top-down lithography, molecular electronics is promising to help maintain the exponential increase in component densities via using molecular building blocks to fabricate electronic components from the bottom up. It offers smaller, faster, and more energy-efficient electronic and photonic systems. A self-assembled monolayer (SAM) of molecules is a layer of molecules that self-assembles on a substrate. They are mechanically flexible, optically transparent, low-cost, and easy to fabricate. A large-area multi-layer structure has been designed and investigated by the team, where a SAM of designed molecules is sandwiched between graphene and gold electrodes. Each molecule can act as a quantum dot, with all molecules conducting in parallel. When a source-drain bias is applied, significant current flows only if a molecular orbital (HOMO or LUMO) lies within the source-drain energy window. If electrons tunnel sequentially on and off the molecule, the charge on the molecule is well-defined and the finite charging energy causes Coulomb blockade of transport until the molecular orbital comes within the energy window. This produces ‘Coulomb diamonds’ in the conductance vs source-drain and gate voltages. For different tunnel barriers at either end of the molecule, it is harder for electrons to tunnel out of the dot than in (or vice versa), resulting in the accumulation of two or more charges and a ‘Coulomb staircase’ in the current vs voltage. This nanostructure exhibits highly reproducible Coulomb-staircase patterns, together with additional oscillations, which are believed to be attributed to molecular vibrations. Molecules are more isolated than semiconductor dots, and so have a discrete phonon spectrum. When tunnelling into or out of a molecule, one or more vibronic states can be excited in the molecule, providing additional transport channels and resulting in additional peaks in the conductance. For useful molecular electronic devices, achieving the optimum orbital alignment of molecules to the Fermi energy in the leads is essential. To explore it, a drop of ionic liquid is employed on top of the graphene to establish an electric field at the graphene, which screens poorly, gating the molecules underneath. Results for various molecules with different alignments of Fermi energy to HOMO have shown highly reproducible Coulomb-diamond patterns, which agree reasonably with DFT calculations. In summary, this large-area SAM molecular junction is a promising candidate for future electronic circuits. (1) The small size (1-10nm) of the molecules and good flexibility of the SAM lead to the scalable assembly of ultra-high densities of functional molecules, with advantages in cost, efficiency, and power dissipation. (2) The contacting technique using graphene enables mass fabrication. (3) Its well-observed Coulomb blockade behaviour, narrow molecular resonances, and well-resolved vibronic states offer good tuneability for various functionalities, such as switches, thermoelectric generators, and memristors, etc.

Keywords: molecular electronics, Coulomb blokade, electron-phonon coupling, self-assembled monolayer

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Authors: Ágnes Győri, Éva Perpék, Zsófia Bauer, Zsuzsanna Elek

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The aim of the research (funded by Hungarian national grant, NFKI- FK 138315) is to examine the professional mobility, mental health and work environment of social workers with a complex approach. Previous international and Hungarian research has pointed out that those working in the helping professions are strongly exposed to the risk of emotional-mental-physical exhaustion due to stress. Mental and physical strain, as well as lack of coping (can) cause health problems, but its role in career change and high labor turnover has also been proven. Even though satisfaction with working conditions of those employed in the human service sector in the context of the stress burden has been researched extensively, there is a lack of large-sample international and Hungarian domestic studies exploring the effects of profession-specific conditions. Nor has it been examined how the specific features of the social profession and mental health affect the career mobility of the professionals concerned. In our research, these factors and their correlations are analyzed by means of mixed methodology, utilizing the benefits of netnographic big data analysis and a sector-specific quantitative survey. The netnographic analysis of open web content generated inside and outside the social profession offers a holistic overview of the influencing factors related to mental health and the work environment of social workers. On the one hand, the topics and topoi emerging in the external discourse concerning the sector are examined, and on the other hand, focus on mentions and streams of comments regarding the profession, burnout, stress, coping, as well as labor turnover and career changes among social professionals. The analysis focuses on new trends and changes in discourse that have emerged during and after the pandemic. In addition to the online conversation analysis, a survey of social professionals with a specific focus has been conducted. The questionnaire is based on input from the first two research phases. The applied approach underlines that the mobility paths of social professionals can only be understood if, apart from the general working conditions, the specific features of social work and the effects of certain aspects of mental health (emotional-mental-physical strain, resilience) are taken into account as well. In this paper, the preliminary results from this innovative methodological mix are presented, with the aim of highlighting new opportunities and dimensions in the research on social work. A gap in existing research is aimed to be filled both on a methodological and empirical level, and the Hungarian domestic findings can create a feasible and relevant framework for a further international investigation and cross-cultural comparative analysis. Said results can contribute to the foundation of organizational and policy-level interventions, targeted programs whereby the risk of burnout and the rate of career abandonment can be reduced. Exploring different aspects of resilience and mapping personality strengths can be a starting point for stress-management, motivation-building, and personality-development training for social professionals.

Keywords: burnout, mixed methods, netnography, professional mobility, social work

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Authors: Mirain Rhys, Kevin Smith

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In 2017, the Welsh Government introduced an ambitious, new strategy to increase the number of Welsh speakers in Wales to 1 million by 2050. The Welsh education system is a vitally important feature of this strategy. All children attending state schools in Wales learn Welsh as a second language until the age of 16 and are assessed at General Certificate of Secondary Education (GCSE) level. In 2013, a review of Welsh second language instruction in Key Stages 3 and 4 was completed. The report identified considerable gaps in teachers’ preparation and training for teaching Welsh; poor Welsh language ethos at many schools; and a general lack of resources to support the instruction of Welsh. Recommendations were made across a number of dimensions including curriculum content, pedagogical practice, and teacher assessment, training, and resources. With a new national curriculum currently in development, this study builds on this review and provides unprecedented detail into pupils’ and teachers’ perceptions of Welsh language instruction. The current research built on data taken from an existing capacity building research project on Welsh education, the Wales multi-cohort study (WMS). Quantitative data taken from WMS surveys with over 1200 pupils in schools in Wales indicated that Welsh language lessons were the least enjoyable subject among pupils. The current research aimed to unpick pupil experiences in order to add to the policy development context. To achieve this, forty-four pupils and four teachers in three schools from the larger WMS sample participated in focus groups. Participants from years 9, 11 and 13 who had indicated positive, negative and neutral attitudes towards the Welsh language in a previous WMS survey were selected. Questions were based on previous research exploring issues including, but not limited to pedagogy, policy, assessment, engagement and (teacher) training. A thematic analysis of the focus group recordings revealed that the majority of participants held positive views around keeping the language alive but did not want to take on responsibility for its maintenance. These views were almost entirely based on their experiences of learning Welsh at school, especially in relation to their perceived lack of choice and opinions around particular lesson strategies and assessment. Analysis of teacher interviews highlighted a distinct lack of resources (materials and staff alike) compared to modern foreign languages, which had a negative impact on student motivation and attitudes. Both staff and students indicated a need for more practical, oral language instruction which could lead to Welsh being used outside the classroom. The data corroborate many of the review’s previous findings, but what makes this research distinctive is the way in which pupils poignantly address generally misguided aims for Welsh language instruction, poor pedagogical practice and a general disconnect between Welsh instruction and its daily use in their lives. These findings emphasize the complexity of incorporating the educational sector in strategies for Welsh language maintenance and the complications arising from pedagogical training, support, and resources, as well as teacher and pupil perceptions of, and attitudes towards, teaching and learning Welsh.

Keywords: bilingual education, language maintenance, language revitalisation, minority languages, Wales

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Authors: Andrea N. Alarcon, Julian D. Castro, Gloria C. Rojas, Paola A. Vaca, Santiago Ortiz, Gustavo Martinez, Pablo D. Lemoine

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Recently, electoral results across many countries have shown to be inconsistent with rational decision theory, which states that individuals make decisions based on maximizing benefits and reducing risks. An alternative explanation has emerged: Fear and rage-driven vote have been proved to be highly effective for political persuasion and mobilization. This phenomenon has been evident in the 2016 elections in the United States, 2006 elections in Mexico, 1998 elections in Venezuela, and 2004 elections in Bolivia. In Colombia, it has occurred recently in the 2016 plebiscite for peace and 2018 presidential elections. The aim of this study is to explain this phenomenon using cultural cognition theory, referring to the psychological predisposition individuals have to believe that its own and its peer´s behavior is correct and, therefore, beneficial to the entire society. Cultural cognition refers to the tendency of individuals to fit perceived risks, and factual beliefs into group shared values; the Cultural Cognition Worldview Scales (CCWS) measures cultural perceptions through two different dimensions: Individualism-communitarianism and hierarchy-egalitarianism. The former refers to attitudes towards social dominance based on conspicuous and static characteristics (sex, ethnicity or social class), while the latter refers to attitudes towards a social ordering in which it is expected from individuals to guarantee their own wellbeing without society´s or government´s intervention. A probabilistic national sample was obtained from different polls from the consulting and public opinion company Centro Nacional de Consultoría. Sociodemographic data was obtained along with CCWS scores, a subjective measure of left-right ideological placement and vote intention for 2019 Mayor´s elections were also included in the questionnaires. Finally, the question “In your opinion, what is the greatest risk Colombia is facing right now?” was included to identify perceived risk in the population. Preliminary results show that Colombians are highly distributed among hierarchical communitarians and egalitarian individualists (30.9% and 31.7%, respectively), and to a less extent among hierarchical individualists and egalitarian communitarians (19% and 18.4%, respectively). Males tended to be more hierarchical (p < .000) and communitarian (p=.009) than females. ANOVA´s revealed statistically significant differences between groups (quadrants) for the level of schooling, left-right ideological orientation, and stratum (p < .000 for all), and proportion differences revealed statistically significant differences for groups of age (p < .001). Differences and distributions for vote intention and perceived risks are still being processed and results are yet to be analyzed. Results show that Colombians are differentially distributed among quadrants in regard to sociodemographic data and left-right ideological orientation. These preliminary results indicate that this study may shed some light on why Colombians vote the way they do, and future qualitative data will show the fears emerging from the identified values in the CCWS and the relation this has with vote intention.

Keywords: communitarianism, cultural cognition, egalitarianism, hierarchy, individualism, perceived risks

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Authors: Karen Koellner, Nanette Seago, Jennifer Jacobs, Helen Garnier

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Although studies of teacher professional development (PD) are prevalent, surprisingly most have only produced incremental shifts in teachers’ learning and their impact on students. There is a critical need to understand what teachers take up and use in their classroom practice after attending PD and why we often do not see greater changes in learning and practice. This paper is based on a mixed methods efficacy study of the Learning and Teaching Geometry (LTG) video-based mathematics professional development materials. The extent to which the materials produce a beneficial impact on teachers’ mathematics knowledge, classroom practices, and their students’ knowledge in the domain of geometry through a group-randomized experimental design are considered. Included is a close-up examination of a small group of teachers to better understand their interpretations of the workshops and their classroom uptake. The participants included 103 secondary mathematics teachers serving grades 6-12 from two US states in different regions. Randomization was conducted at the school level, with 23 schools and 49 teachers assigned to the treatment group and 18 schools and 54 teachers assigned to the comparison group. The case study examination included twelve treatment teachers. PD workshops for treatment teachers began in Summer 2016. Nine full days of professional development were offered to teachers, beginning with the one-week institute (Summer 2016) and four days of PD throughout the academic year. The same facilitator-led all of the workshops, after completing a facilitator preparation process that included a multi-faceted assessment of fidelity. The overall impact of the LTG PD program was assessed from multiple sources: two teacher content assessments, two PD embedded assessments, pre-post-post videotaped classroom observations, and student assessments. Additional data were collected from the case study teachers including additional videotaped classroom observations and interviews. Repeated measures ANOVA analyses were used to detect patterns of change in the treatment teachers’ content knowledge before and after completion of the LTG PD, relative to the comparison group. No significant effects were found across the two groups of teachers on the two teacher content assessments. Teachers were rated on the quality of their mathematics instruction captured in videotaped classroom observations using the Math in Common Observation Protocol. On average, teachers who attended the LTG PD intervention improved their ability to engage students in mathematical reasoning and to provide accurate, coherent, and well-justified mathematical content. In addition, the LTG PD intervention and instruction that engaged students in mathematical practices both positively and significantly predicted greater student knowledge gains. Teacher knowledge was not a significant predictor. Twelve treatment teachers self-selected to serve as case study teachers to provide additional videotapes in which they felt they were using something from the PD they learned and experienced. Project staff analyzed the videos, compared them to previous videos and interviewed the teachers regarding their uptake of the PD related to content knowledge, pedagogical knowledge and resources used. The full paper will include the case study of Ana to illustrate the factors involved in what teachers take up and use from participating in the LTG PD.

Keywords: geometry, mathematics professional development, pedagogical content knowledge, teacher learning

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Authors: Adinew Gebremeskel Tizazu

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The effect of soil-structure interaction on the dynamic response of reinforced concrete buildings of regular and symmetrical geometry are considered in this study. The structures are presumed to be generally embedded in a homogenous soil formation underlain by very stiff material or bedrock. The structure-foundation–soil system is excited at the base by an earthquake ground motion. The superstructure is idealized as a system with lumped masses concentrated at the floor levels, and coupled with the substructure. The substructure system, which comprises of the foundation and soil, is represented, and replaced by springs and dashpots. Frequency-dependent impedances of the foundation system are incorporated in the discrete model in terms of the springs and dashpots coefficients. The excitation applied to the model is field ground motions of actual earthquake records. Modal superposition principle is employed to transform the equations of motion in geometrical coordinates to modal coordinates. However, the modal equations remain coupled with respect to damping terms due to the difference in damping mechanisms of the superstructure and the soil. Hence, proportional damping for the coupled structural system may not be assumed. An iterative approach is adopted and programmed to solve the system of coupled equations of motion in modal coordinates to obtain the displacement responses of the system. Parametric studies for responses of building structures with regular and symmetric plans of different structural properties and heights are made for fixed and flexible base conditions, for different soil conditions encountered in Addis Ababa. The displacement, base shear and base overturning moments are used in the comparison of different types of structures for various foundation embedment depths, site conditions and height of structures. These values are compared against those of fixed base structure. The study shows that the flexible base structures, generally exhibit different responses from those structures with fixed base. Basically, the natural circular frequencies, the base shears and the inter-story displacements for the flexible base are less than those of the fixed base structures. This trend is particularly evident when the flexible soil has large thickness. In contrast, the trend becomes less predictable, when the thickness of the flexible soil decreases. Moreover, in the latter case, the iteration undulates significantly making the prediction difficult. This is attributed to the highly jagged nature of the impedance functions of frequencies for such formations. In this case, it is difficult to conclude whether the conventional fixed-base approach yields conservative design forces, as is the case for soil formations of large thickness.

Keywords: effect of soil structure, dynamic response corroborated, the modal superposition principle, parametric studies

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