Search results for: leading and trailing edge corrugations

Authors: Zhanna Yermekova, Sergey Roslyakov

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Solution combustion synthesis (SCS) is the unique method which multiple times has proved itself as an effective and efficient approach for the versatile synthesis of a variety of materials. It has significant advantages such as relatively simple handling process, high rates of product synthesis, mixing of the precursors on a molecular level, and fabrication of the nanoproducts as a result. Nowadays, an overwhelming majority of solution combustion investigations performed through the volume combustion synthesis (VCS) where the entire liquid precursor is heated until the combustion self-initiates throughout the volume. Less amount of the experiments devoted to the steady-state self-propagating mode of SCS. Under the beforementioned regime, the precursor solution is dried until the gel-like media, and later on, the gel substance is locally ignited. In such a case, a combustion wave propagates in a self-sustaining mode as in conventional solid combustion synthesis. Even less attention is given to the impregnated active layer (IAL) mode of solution combustion. An IAL approach to the synthesis is implying that the solution combustion of the precursors should be initiated on the surface of the third chemical or inside the third substance. This work is aiming to emphasize an underestimated role of the impregnated active layer mode of the solution combustion synthesis for the fundamental studies of the combustion mechanisms. It also serves the purpose of popularizing the technical terms and clarifying the difference between them. In order to do so, the solution combustion synthesis of γ-FeNi (PDF#47-1417) alloy has been accomplished within short (seconds) one-step reaction of metal precursors with hexamethylenetetramine (HTMA) fuel. An idea of the special role of the Ni in a process of alloy formation was suggested and confirmed with the particularly organized set of experiments. The first set of experiments were conducted in a conventional steady-state self-propagating mode of SCS. An alloy was synthesized as a single monophasic product. In two other experiments, the synthesis was divided into two independent processes which are possible under the IAL mode of solution combustion. The sequence of the process was changed according to the equations which are describing an Experiment A and B below: Experiment A: Step 1. Fe(NO₃)₃*9H₂O + HMTA = FeO + gas products; Step 2. FeO + Ni(NO₃)₂*6H₂O + HMTA = Ni + FeO + gas products; Experiment B: Step 1. Ni(NO₃)₂*6H₂O + HMTA = Ni + gas products; Step 2. Ni + Fe(NO₃)₃*9H₂O + HMTA = Fe₃Ni₂+ traces (Ni + FeO). Based on the IAL experiment results, one can see that combustion of the Fe(NO₃)₃9H₂O on the surface of the Ni is leading to the alloy formation while presence of the already formed FeO does not affect the Ni(NO₃)₂*6H₂O + HMTA reaction in any way and Ni is the main product of the synthesis.

Keywords: alloy, hexamethylenetetramine, impregnated active layer mode, mechanism, solution combustion synthesis

Procedia PDF Downloads 115

Authors: Deenadayalan Govender

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In South Africa, similar to nations globally, the prevailing tangible link between people and the state is public infrastructure. Services delivered through infrastructure to the people and to the state form a critical enabler for social development in communities and economic development in the country. In this regard, infrastructure, being the backbone to a nation’s prosperity, ideally should be effectively maintained for seamless delivery of services. South African infrastructure is in a state of deterioration, which is leading to infrastructure dysfunction and collapse and is negatively affecting development of the economy. This infrastructure deterioration stems from deficiencies in maintenance practices and strategies. From the birth of South African democracy, government has pursued socio-economic transformation and the delivery of critical basic services to decrease the broadening boundaries of disparity. In this regard, the National Infrastructure Plan borne from strategies encompassed in the National Development Plan is given priority by government in delivering strategic catalytic infrastructure projects. The National Infrastructure Plan is perceived to be the key in unlocking opportunities that generate economic growth, kerb joblessness, alleviate poverty, create new entrepreneurial prospects, and mitigate population expansion and rapid urbanisation. Socio-economic transformation benefits from new infrastructure spend is not being realised as initially anticipated. In this context, South Africa is currently in a state of weakening economic growth, with further amassed levels of joblessness, unremitting poverty and inequality. Due to investor reluctance, solicitation of strategic infrastructure funding is progressively becoming a debilitating challenge in all government institutions. Exacerbating these circumstances further, is substandard functionality of existing infrastructure subsequent to inadequate maintenance practices. This in-depth multi-sectoral study into the state of infrastructure is to understand the principal reasons for infrastructure functionality regression better; furthermore, prioritised investigations into progressive maintenance strategies is focused upon. Resultant recommendations reveal enhanced maintenance strategies, with a vision to capitalize on infrastructure design life, and also give special emphasis to socio-economic development imperatives in the long-term. The research method is principally based on descriptive methods (survey, historical, content analysis, qualitative).

Keywords: infrastructure, maintenance, socio-economic, strategies

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Authors: Lucksini Raveendran

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Introduction: This mixed-methods study focuses on the experiences of ethnocultural youth and families in Canada, identifying key barriers and opportunities to inform service programming and policies that can better meet their mental health needs during the COVID-19 pandemic and beyond. Methods: Mental Health Commission of Canada's Headstrong initiative administered the youth survey (April – June 2020) and family survey (June – August 2020) with a total sample size of 137 and 481 respondents, respectively. Thematic analysis was conducted to identify key challenges faced, coping strategies used, and help-seeking behaviours. A similar approach was also applied to the family survey data, but instead, a representative sample was collated to analyze geographically variable and ethnically diverse subgroups. Results and analysis: Multiple challenges have impacted families, including increased feelings of loneliness and distress from border travel restrictions, especially among those navigating pregnancy alone or managing children with developmental needs, which is often understudied. Also, marginalized groups were disproportionately affected by inequitable access to communication technologies, further deepening the digital divide. Some reported living in congregated homes with regular conflicts, thus leading to increased anxiety and exposure to violence. For many families, urbanicity and ethnicity played a key role in how families reported coping with feelings of uncertainty while managing work commitments, navigating community resources, fulfilling care responsibilities, and homeschooling children of all ages. Despite these challenges, there was evidence of post-traumatic growth and building community resiliency. Conclusions and implications for policy, practice, or additional research: There is a need to foster opportunities to promote and sustain mental health, wellness, and resilience for families through social connections. Also, intersectionality must be embedded in the collection, analysis, and application of data to improve equitable access to evidence-based and recovery-oriented mental health supports among diverse families in Canada. Lastly, address future research on the long-term COVID-19 impacts of travel border restrictions on family wellness.

Keywords: mental health, youth mental health, family wellness, health equity

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Authors: Sayed Mansour, Mohammad Aldoasri, Nagib Elmarzugi, Nadia A. Al-Mouallimi

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The archaeological large stone used in construction of ancient Pharaonic tombs, temples, obelisks and other sculptures, always subject to physicomechanical deterioration and destructive forces, leading to their partial or total broken. The task of reassembling this type of artifact represent a big challenge for the conservators. Recently, the researchers are turning to new technologies to improve the properties of traditional adhesive materials and techniques used in re-assembly of broken large stone. The epoxy resins are used extensively in stone conservation and re-assembly of broken stone because of their outstanding mechanical properties. The introduction of nanoparticles to polymeric adhesives at low percentages may lead to substantial improvements of their mechanical performances in structural joints and large objects. The aim of this study is to evaluate the effectiveness of clay nanoparticles in enhancing the performances of epoxy adhesives used in re-assembly of archaeological massive stone by adding proper amounts of those nanoparticles. The nanoparticles reinforced epoxy nanocomposite was prepared by direct melt mixing with a nanoparticles content of 3% (w/v), and then mould forming in the form of rectangular samples, and used as adhesive for experimental stone samples. Scanning electron microscopy (SEM) was employed to investigate the morphology of the prepared nanocomposites, and the distribution of nanoparticles inside the composites. The stability and efficiency of the prepared epoxy-nanocomposites and stone block assemblies with new formulated adhesives were tested by aging artificially the samples under different environmental conditions. The effect of incorporating clay nanoparticles on the mechanical properties of epoxy adhesives was evaluated comparatively before and after aging by measuring the tensile, compressive, and Elongation strength tests. The morphological studies revealed that the mixture process between epoxy and nanoparticles has succeeded with a relatively homogeneous morphology and good dispersion in low nano-particles loadings in epoxy matrix was obtained. The results show that the epoxy-clay nanocomposites exhibited superior tensile, compressive, and Elongation strength. Moreover, a marked improvement of the mechanical properties of stone joints increased in all states by adding nano-clay to epoxy in comparison with pure epoxy resin.

Keywords: epoxy resins, nanocomposites, clay nanoparticles, re-assembly, archaeological massive stones, mechanical properties

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

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

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

Procedia PDF Downloads 87

Authors: Girgis Younan, Ikram Eltayeb

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Geigeria alata belongs to the family Asteraceae, is an effective plant traditionally used in Sudan as a therapy for hepatic disease and as an antiepileptic, antispasmodic and to treat cough and intestinal complaints.The liver is responsible for many critical functions within the body and any liver disease or injury will result in the loss of those functions leading to significant damage in the body. Liver diseases cause increase in liver enzymes (AST, ALP ALT) and total bilirubin and a decrease in total blood protein level. The objective of this study is to investigate the hepato-protective activity of Geigeria alata leaves ethanolic extract. The plant leaves were extracted using 96% ethanol using Soxhlet apparatus. The hepatoprotective effect was determined using 25 wistar rats, the rats was divided to 5 groups, each group contain 5 rats: [Normal control group] receiving purified water, liver damage was induced in wistar rats by administering a 1:1 (v/v) mixture of CCl4 (1.25 ml/kg) and olive oil once at day four of the experiment [negative control group]. Two doses of extract [400mg/kg and 200mg/kg] was applied daily for 7 days, and standard drug Silymarin (200 mg/kg) were administered daily for 7 days to CCl4-treated rats. The degree of hepato-protective activity was evaluated by determining the hepatic marker enzymes AST, ALP, ALT, total Bilirubin and total proteins (TP). Results have shown that, the extract of G.alata leaves reduced the level of liver enzymes ALT, AST, ALP, total bilirubin and increased the level of total proteins. Since the levels of liver enzymes; bilirubin and total protein are considered as markers of liver function, the extract has proven to reduce the detrimental effects of liver toxicity induced using CCl4. The hepato-protective effect of extract on liver was found to be dose dependent, where the 400mg/kg dose of the extract exhibited higher activity than 200mg/kg dose. In addition, the effect of the higher dose (400mg/kg) of the extract was found to be higher than Silymarin standard drug. The result concludes that, G.alata leaves extract was found to exhibit profound hepato-protective activity, which justifies the traditional use of the plant for the treatment of hepatic diseases.

Keywords: alata, extract, geigeria, hepatoprotective

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Authors: Rashmi Dyondi, Shishir K. Jha

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The purpose of the paper is to address the strategic risk issues surrounding Hindi film distribution in Mumbai for a film distributor, who acts as an entrepreneur when launching a product (movie) in the market (film territory).The paper undertakes a fundamental review of films and risk in the Hindi film industry and applies Grounded Theory technique to understand the complex phenomena of risk taking behavior of the film distributors (both independent and studios) in Mumbai. Rich in-depth interviews with distributors are coded to develop core categories through constant comparison leading to conceptualization of the phenomena of interest. This paper is a first-of-its-kind-attempt to understand risk behavior of a distributor, which is akin to entrepreneurial risk behavior under conditions of uncertainty. Unlike extensive scholarly work on dynamics of Hollywood motion picture industry, Hindi film industry is an under-researched area till now. Especially how do film distributors perceive risk is an unexplored study for the Hindi film industry. Films are unique experience products and the film distributor acts as an entrepreneur assuming high risks given the uncertainty in the motion picture business. With the entry of mighty corporate studios and astronomical film budgets posing serious business threats to the independent distributors, there is a need for an in-depth qualitative enquiry (applying grounded theory technique) for unraveling the definition of risk for the independent distributors in Mumbai vis-à-vis the corporate studios. Need for good content was a common challenge to both the groups in the present state of the industry, however corporate studios with their distinct ideologies, focus on own productions and financial power faced different set of challenges than the independents (like achieving sustainability in business). Softer issues like market goodwill and relations with producers, honesty in business dealings and transparency came out to be clear markers for success of independents in long run. The findings from the qualitative analysis stress on different elements of risk and challenges as perceived by the two groups of distributors in the Hindi film industry and provide a future research agenda for empirical investigation of determinants of box-office success of Hindi films distributed in Mumbai.

Keywords: entrepreneurial risk behavior, film distribution strategy, Hindi film industry, risk

Procedia PDF Downloads 297

Authors: Christian Skowronski, Andrew Shanholtzer, Brent Yelton, Muayad Almahariq, Daniel J. Krauss

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Prostate cancer has the third highest incidence rate and is the second leading cause of cancer death for men in the United States. Of the diagnostic tools available for intermediate-risk prostate cancer, magnetic resonance imaging (MRI) provides superior soft tissue delineation serving as a valuable tool for both diagnosis and treatment planning. Currently, there is minimal data regarding the practical utility of MRI for evaluation of intermediate-risk prostate cancer. As such, the National Comprehensive Cancer Network’s guidelines indicate MRI as optional in intermediate-risk prostate cancer evaluation. This project aims to elucidate whether MRI affects radiation treatment decisions for intermediate-risk prostate cancer. This was a retrospective study evaluating 210 patients with intermediate-risk prostate cancer, treated with definitive radiotherapy at our institution between 2019-2020. NCCN risk stratification criteria were used to define intermediate-risk prostate cancer. Patients were divided into two groups: those with pretreatment prostate MRI, and those without pretreatment prostate MRI. We compared the use of external beam radiotherapy, brachytherapy alone, brachytherapy boost, and androgen depravation therapy between the two groups. Inverse probability of treatment weighting was used to match the two groups for age, comorbidity index, American Urologic Association symptoms index, pretreatment PSA, grade group, and percent core involvement on prostate biopsy. Wilcoxon Rank Sum and Chi-squared tests were used to compare continuous and categorical variables. Of the patients who met the study’s eligibility criteria, 133 had a prostate MRI and 77 did not. Following propensity matching, there were no differences between baseline characteristics between the two groups. There were no statistically significant differences in treatments pursued between the two groups: 42% vs 47% were treated with brachytherapy alone, 40% vs 42% were treated with external beam radiotherapy alone, 18% vs 12% were treated with external beam radiotherapy with a brachytherapy boost, and 24% vs 17% received androgen deprivation therapy in the non-MRI and MRI groups, respectively. This analysis suggests that pretreatment MRI does not significantly impact radiation therapy or androgen deprivation therapy decisions in patients with intermediate-risk prostate cancer. Obtaining a pretreatment prostate MRI should be used judiciously and pursued only to answer a specific question, for which the answer is likely to impact treatment decision. Further follow up is needed to correlate MRI findings with their impacts on specific oncologic outcomes.

Keywords: magnetic resonance imaging, prostate cancer, definitive radiotherapy, gleason score 7

Procedia PDF Downloads 71

Authors: Placide Poba-Nzaou, Anicet Tchibozo, Malatsi Galani, Ali Etkkali, Erwin Halim

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Artificial intelligence (AI) is a general-purpose technology that is transforming many industries, working life and society by stimulating economic growth and innovation. Despite the huge potential of benefits to be generated, the adoption of AI varies from one organization to another, from one region to another, and from one industry to another, due in part to obstacles that can inhibit an organization or organizations located in a specific geographic region or operating in a specific industry from adopting AI technology. In this context, these obstacles and their implications for AI adoption from the perspective of configurational theory is important for at least three reasons: (1) understanding these obstacles is the first step in enabling policymakers and providers to make an informed decision in stimulating AI adoption (2) most studies have investigating obstacles or challenges of AI adoption in isolation with linear assumptions while configurational theory offers a holistic and multifaceted way of investigating the intricate interactions between perceived obstacles and barriers helping to assess their synergetic combination while holding assumptions of non-linearity leading to insights that would otherwise be out of the scope of studies investigating these obstacles in isolation. This study aims to pursue two objectives: (1) characterize organizations by uncovering the typical profiles of combinations of 15 internal and external obstacles that may prevent organizations from adopting AI technology, (2) assess the variation in terms of intensity of AI adoption associated with each configuration. We used data from a survey of AI adoption by organizations conducted throughout the EU27, Norway, Iceland and the UK (N=7549). Cluster analysis and discriminant analysis help uncover configurations of organizations based on the 15 obstacles, including eight external and seven internal. Second, we compared the clusters according to AI adoption intensity using an analysis of variance (ANOVA) and a Tamhane T2 post hoc test. The study uncovers three strongly separated clusters of organizations based on perceived obstacles to AI adoption. The clusters are labeled according to their magnitude of perceived obstacles to AI adoption: (1) Cluster I – High Level of perceived obstacles (N = 2449, 32.4%)(2) Cluster II – Low Level of perceived obstacles (N =1879, 24.9%) (3) Cluster III – Moderate Level of perceived obstacles (N =3221, 42.7%). The proposed taxonomy goes beyond the normative understanding of perceived obstacles to AI adoption and associated implications: it provides a well-structured and parsimonious lens that is useful for policymakers, AI technology providers, and researchers. Surprisingly, the ANOVAs revealed a “high level of perceived obstacles” cluster associated with a significantly high intensity of AI adoption.

Keywords: Artificial intelligence (AI), obstacles, adoption, taxonomy.

Procedia PDF Downloads 86

Authors: Djehich Mohamed Yousri

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The national sovereignty of states is now facing a dangerous situation that has witnessed a clear exacerbation of the restrictions that this sovereignty has known for quite some time, if not since the establishment of the sovereign national state in the first place, and things have reached this way to the extent that a group of analysts and commentators are talking about the demise or disappearance of the phenomenon of sovereignty Patriotism, a judgment that some consider exaggerated, although there is agreement on the seriousness of what has afflicted the national sovereignty of medium and small states in particular. In fact, the phenomenon of national sovereignty has not completely ended, as there is still a category of countries that are able to disagree with the American will without disappearing from the world map, as happened with the Soviet Union. China, some European countries, and some countries with leading regional roles are still able to deal with This administration, with rational and complex calculations, makes the restrictions on its sovereignty minimal, or at least draws a red line in front of the vital interests of those countries that the restrictions on sovereignty cannot cross, and it is certain that strengthening internal democratic development in countries will increase their ability to challenge external restrictions. On its sovereignty to the extent that this development creates a cohesive society in the face of external hegemony attempts, as well as to the extent that it eliminates some pretexts for interference in the internal affairs of states, including the claim of a lack of democracy or lack of respect for human rights in it. What led to transformations in the international arena in the wake of globalization and its effects on international aspects, including national sovereignty and the principle of state independence. Which was marred by several currents, which led to affecting it in a negative way, and this is what poor countries suffer from at the expense of rich countries, which led us to research the extent of the presence of national sovereignty on the international arena, and the extent to which the principle of non-interference in affairs is applied or existed. The internal affairs of states, which are stipulated in the Charter of the United Nations in the modern era, the theory of sovereignty has been subjected to substantial criticism and abandonment by many on the grounds that it is inconsistent with the current conditions of the international community. In fact, the theory of sovereignty has been misused to justify internal tyranny and international chaos. This theory has hindered the development of international law, the work of international organizations and the dominance of strong states over weak ones. At the present time, the concept of sovereignty has moved towards direction, as the transformations of the international system in the economic, political and military fields have led to the decline and erosion of the idea of the sovereignty of the national state.

Keywords: sovereignty, intervention, non-interference, globalization, humanitarian intervention

Procedia PDF Downloads 49

Authors: Tarek K. Jalouta, Jolietta R. Holliman, Kathryn R. Burke, Kathleen M. Bewley-Thomas

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Background: Chronic hepatitis C virus (HCV) infection is one of the leading causes of liver cirrhosis and hepatocellular carcinoma. In the United States, HCV screening awareness, treatment, and linkage to care are under continues ascending progress. However, still millions of people are asymptomatically infected and undiagnosed yet. Through this community mission, we sought to identify the best and the newest strategies to identify those infected people to educate them, link them to care and cure them. Methods: We have identified patients that did not have a prior HCV screening in our Electronic medical record (EMR) including all our different hospital locations (South Suburban Chicago, Northern, Western and Central Indiana). Providing education to all Primary care/Gastroenterology/Infectious diseases providers and staff in the clinic to increase awareness of the HCV screening. Health-related quality of life, chronic clinical complications, and demographics data were collected for each patient. All outcomes of HCV antibody-reactive and HCV RNA–positive results were identified and statistically analyzed. Results: From July 2016 to July 2018 we screened 35,720 individuals of birth cohort in our different Franciscan’s health medical centers. Of the screened population, 986 (2.7%) individuals were HCV AB-reactive. Of those, 319 (1%) patients were HCV RNA-positive, and 264 patients were counseled and linked to providers. 34 patients initiated anti-HCV therapy with successful treatment. Conclusions: Our HCV screening augmentation project considered the largest screening program in the Midwest. Augmenting the HCV screening process through creating a Best Practice Alert (BPA) in the EMR (Epic Sys.) and point of care testing could be helpful. Although continued work is required, our team is working on increase screening through adding HCV test to CBC-Panels in Emergency Department settings, phone calls to all birth cohort individuals through Robo-Calling System aimed to reach 75,000 individuals by 2019. However, a better linkage to care and referral monitoring system to all HCV RNA positive patients is still needed, and access to therapy, especially for uninsured patients, is challenging.

Keywords: chronic hepatitis C, chronic hepatitis C treatment, chronic hepatitis C screening, chronic hepatitis C prevention, liver cancer

Procedia PDF Downloads 109

Authors: Breno Barrreto Silva, Agnieszka Otwinowska, Katarzyna Kutylowska

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Research comparing lexical learning following the writing of sentences and longer texts with keywords is limited and contradictory. One possibility is that the recursivity of writing may enhance processing and increase lexical learning; another possibility is that the higher cognitive load of complex-text writing (e.g., essays), at least when timed, may hinder the learning of words. In our study, we selected 2 sets of 10 academic keywords matched for part of speech, length (number of characters), frequency (SUBTLEXus), and concreteness, and we asked 90 L1-Polish advanced-level English majors to use the keywords when writing sentences, timed (60 minutes) or untimed essays. First, all participants wrote a timed Control essay (60 minutes) without keywords. Then different groups produced Timed essays (60 minutes; n=33), Untimed essays (n=24), or Sentences (n=33) using the two sets of glossed keywords (counterbalanced). The comparability of the participants in the three groups was ensured by matching them for proficiency in English (LexTALE), and for few measures derived from the control essay: VocD (assessing productive lexical diversity), normed errors (assessing productive accuracy), words per minute (assessing productive written fluency), and holistic scores (assessing overall quality of production). We measured lexical learning (depth and breadth) via an adapted Vocabulary Knowledge Scale (VKS) and a free association test. Cognitive load was measured in the three essays (Control, Timed, Untimed) using normed number of errors and holistic scores (TOEFL criteria). The number of errors and essay scores were obtained from two raters (interrater reliability Pearson’s r=.78-91). Generalized linear mixed models showed no difference in the breadth and depth of keyword knowledge after writing Sentences, Timed essays, and Untimed essays. The task-based measurements found that Control and Timed essays had similar holistic scores, but that Untimed essay had better quality than Timed essay. Also, Untimed essay was the most accurate, and Timed essay the most error prone. Concluding, using keywords in Timed, but not Untimed, essays increased cognitive load, leading to more errors and lower quality. Still, writing sentences and essays yielded similar lexical learning, and differences in the cognitive load between Timed and Untimed essays did not affect lexical acquisition.

Keywords: learning academic words, writing essays, cognitive load, english as an L2

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Authors: Yawen Dai, Ping Cheng, Jian Ru Gong

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Photoelctrochemical (PEC) water splitting using semiconductors (SCs) provides a convenient way to convert sustainable but intermittent solar energy into clean hydrogen energy, and it has been regarded as one of most promising technology to solve the energy crisis and environmental pollution in modern society. However, the record energy conversion efficiency of a PEC cell (~3%) is still far lower than the commercialization requirement (~10%). The sluggish kinetics of oxygen evolution reaction (OER) half reaction on photoanodes is a significant limiting factor of the PEC device efficiency, and electrocatalysts (ECs) are always deposited on SCs to accelerate the hole injection for OER. However, an active EC cannot guarantee enhanced PEC performance, since the newly emerged SC-EC interface complicates the interfacial charge behavior. Herein, α-Fe2O3 photoanodes coated with Co3O4 and CoO ECs are taken as the model system to glean fundamental understanding on the EC-dependent interfacial charge behavior. Intensity modulated photocurrent spectroscopy and electrochemical impedance spectroscopy were used to investigate the competition between interfacial charge transfer and recombination, which was found to be dominated by the charge storage capacities of ECs. The combined results indicate that both ECs can store holes and increase the hole density on photoanode surface. It is like a double-edged sword that benefit the multi-hole participated OER, as well as aggravate the SC-EC interfacial charge recombination due to the Coulomb attraction, thus leading to a nonmonotonic PEC performance variation trend with the increasing surface hole density. Co3O4 has low hole storage capacity which brings limited interfacial charge recombination, and thus the increased surface holes can be efficiently utilized for OER to generate enhanced photocurrent. In contrast, CoO has overlarge hole storage capacity that causes severe interfacial charge recombination, which hinders hole transfer to electrolyte for OER. Therefore, the PEC performance of α-Fe2O3 is improved by Co3O4 but decreased by CoO despite the similar electrocatalytic activity of the two ECs. First-principle calculation was conducted to further reveal how the charge storage capacity depends on the EC’s intrinsic property, demonstrating that the larger hole storage capacity of CoO than that of Co3O4 is determined by their Co valence states and original Fermi levels. This study raises up a new strategy to manipulate interfacial charge behavior and the resultant PEC performance by the charge storage capacity of ECs, providing insightful guidance for the interface design in PEC devices.

Keywords: charge storage capacity, electrocatalyst, interfacial charge behavior, photoelectrochemistry, water-splitting

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Authors: V. Ziegler, F. Schneider, M. Pesch

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With the EDM264, GRIMM offers a solution for mobile short- and long-term measurements in outdoor areas and at production sites. For research as well as permanent areal observations on a near reference quality base. The model EDM264 features a powerful and robust measuring cell based on optical particle counting (OPC) principle with all the advantages that users of GRIMM's portable aerosol spectrometers are used to. The system is embedded in a compact weather-protection housing with all-weather sampling, heated inlet system, data logger, and meteorological sensor. With TSP, PM10, PM4, PM2.5, PM1, and PMcoarse, the EDM264 provides all fine dust fractions real-time, valid for outdoor applications and calculated with the proven GRIMM enviro-algorithm, as well as six additional dust mass fractions pm10, pm2.5, pm1, inhalable, thoracic and respirable for IAQ and workplace measurements. This highly versatile instrument performs real-time monitoring of particle number, particle size and provides information on particle surface distribution as well as dust mass distribution. GRIMM's EDM264 has 31 equidistant size channels, which are PSL traceable. A high-end data logger enables data acquisition and wireless communication via LTE, WLAN, or wired via Ethernet. Backup copies of the measurement data are stored in the device directly. The rinsing air function, which protects the laser and detector in the optical cell, further increases the reliability and long term stability of the EDM264 under different environmental and climatic conditions. The entire sample volume flow of 1.2 L/min is analyzed by 100% in the optical cell, which assures excellent counting efficiency at low and high concentrations and complies with the ISO 21501-1standard for OPCs. With all these features, the EDM264 is a world-leading dust monitor for precise monitoring of particulate matter and particle number concentration. This highly reliable instrument is an indispensable tool for many users who need to measure aerosol levels and air quality outdoors, on construction sites, or at production facilities.

Keywords: aerosol research, aerial observation, fence line monitoring, wild fire detection

Procedia PDF Downloads 135

Authors: Yun Chen, David Penton, Fazlul Karim, Santosh Aryal, Shahriar Wahid, Peter Taylor, Susan M. Cuddy

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Droughts have severely affected Afghanistan over the last four decades, leading to critical food shortages where two-thirds of the country’s population are in a food crisis. Long years of conflict have lowered the country’s ability to deal with hazards such as drought, which can rapidly escalate into disasters. Understanding the spatial and temporal distribution of droughts is needed to be able to respond effectively to disasters and plan for future occurrences. This study used Standardized Precipitation Evapotranspiration Index (SPEI) at monthly, seasonal, and annual temporal scales to map the spatiotemporal change dynamics of drought characteristics (distribution, frequency, duration, and severity) in Afghanistan. SPEI indices were mapped for river basins, disaggregated into 189 sub-catchments, using monthly precipitation and potential evapotranspiration derived from temperature station observations from 1980 to 2017. The results show these multi-dimensional drought characteristics vary along different years, change among sub-catchments, and differ across temporal scales. During the 38 years, the driest decade and period are the 2000s and 1999–2022, respectively. The 2000–01 water year is the driest, with the whole country experiencing ‘severe’ to ‘extreme’ drought, more than 53% (87 sub-catchments) suffering the worst drought in history, and about 58% (94 sub-catchments) having ‘very frequent’ drought (7 to 8 months) or ‘extremely frequent’ drought (9 to 10 months). The estimated seasonal duration and severity present significant variations across the study area and throughout the study period. The nation also suffered from recurring droughts with varying length and intensity in 2004, 2006, 2008, and, most recently, 2011. There is a trend towards increasing drought with longer duration and higher severity extending all over sub-catchments from southeast to north and central regions. These datasets and maps help to fill the knowledge gap on detailed sub-catchment scale meteorological drought characteristics in Afghanistan. The study findings improve our understanding of the influences of climate change on drought dynamics and can guide catchment planning for reliable adaptation to and mitigation against future droughts.

Keywords: SPEI, precipitation, evapotranspiration, climate extremes

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Authors: Sora Suh, Catherine Michener

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This paper examines the collaborative forms of advocacy that a group of four public school teachers took for their emergent bilingual students in one public school district. While teacher advocacy takes many forms in and out of the classroom, much advocacy work is done by individuals and less by collective action. As a result, individual teachers risk isolation or marginalization in their school contexts when they advocate for immigrant youth. This paper is intended to contribute to the documentation and understanding of teachers’ advocacy work as a collaborative act in teacher education research. The increase of ELs in US classrooms and a corresponding lack of teacher preparation to meet the needs of ELs has motivated the training of educators in linguistically responsive education (e.g., ESL, sheltered English instruction [SEI], bilingual education). Drawing from educational theories of linguistically responsive teaching for preparing educators, we trace the linguistically responsive advocacy work of the teachers. The paper is a multiple case study that tracks how teachers’ discussions on advocacy during a teacher preparation program leading to collaborative actions in their daily teaching lives in and out of school. Data collected includes online discussion forums on the topic of advocacy, course assignments on the topic of advocacy, video-audio recordings of classroom teaching observations, and video-audio recordings of individual and focus group interviews. The findings demonstrate that the teachers’ understanding of advocacy developed through collaborative partnerships formed in the teacher preparation program and grew into active forms of collaborative advocacy in their teaching practice in and out of school. The teachers formed multi-level and collaborative partnerships with teachers, families, community members, policymakers from the local government, and educational researchers to advocate for their emergent bilingual students by planning advocacy events such as new family orientations for emergent bilinguals, professional development for general education teachers on the topic of linguistically responsive instruction, and family nights hosted by the district. The paper’s findings present types of advocacy work in which teachers engage (pedagogical, curricular, out-of-school work) and provide evidence of collaborative advocacy work by a group of engaged educators. The paper highlights the increased agency and effective advocacy of teachers through teacher education and collaborative partnerships and suggests a need for more research on collaborative forms of teacher advocacy for emergent bilinguals.

Keywords: language education, teacher advocacy, language instruction, teacher education

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Authors: James P. Takona

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In a world that is experiencing sharp digital transformations guided by digital technologies, the potential of technology to drive transformation and evolution in the higher is apparent. Higher education is facing a paradigm shift that exposes susceptibilities and threats to fully online programs in the face of post-Covid-19 trends of commodification. This historical moment is likely to be remembered as a critical turning point from analog to digital degree-focused learning modalities, where the default became the pivot point of competition between higher education institutions. Fall 2020 marks a significant inflection point in higher education as students, educators, and government leaders scrutinize higher education's price and value propositions through the new lens of traditional lecture halls versus multiple digitized delivery modes. Online education has since tiled the way for a pedagogical shift in how teachers teach and students learn. The incremental growth of online education in the west can now be attributed to the increasing patronage among students, faculty, and institution administrators. More often than not, college instructors assume paraclete roles in this learning mode, while students become active collaborators and no longer passive learners. This paper offers valuable discernments into the threats, challenges, and opportunities of a massive digital revolution in servicing degree programs. To view digital instruction and learning demands for instructional practices that revolve around collaborative work, engaging students in learning activities, and an engagement that promotes active efforts to solicit strong connections between course activities and expected learning pace for all students. Appropriate digital technologies demand instructors and students need prior solid skills. Need for the use of digital technology to support instruction and learning, intelligent tutoring offers great promise, and failures at implementing digital learning may not improve outcomes for specific student populations. Digital learning benefits students differently depending on their circumstances and background and those of the institution and/or program. Students have alternative options, access to the convenience of learning anytime and anywhere, and the possibility of acquiring and developing new skills leading to lifelong learning.

Keywords: digi̇tized learning, digital education, collaborative work, high education, online education, digitize delivery

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Authors: Mawong R., Bussracumpakorn C.

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Millions of young people around the world have been affected by COVID-19 to their psychological and social effects. Millennials’ stresses have been shaped by a few global issues, including climate change, political instability, and financial crisis. In particular, the spread of COVID-19 has become laying psychological and socioeconomic scars on them. When end-of-life planning turns into more widely discussed, the stigma and taboos around this issue are greatly lessened. End-of-life planning is defined as a future life plan, such as financial, legacy, funeral, and memorial planning. This plan would help millennials to discover the value and meaning of life. This study explores the attitudes of Thai Millennials toward end-of-life planning as a new normal awareness of life in order to initiate an innovative service concept to fit with their value and meaning. The study conducts an in-depth interview with 12 potential participants who have awareness or action on the plan. The framework of the customer journey map is used to analyze the responses to examine trigger points, barriers, beliefs, and expectations. The findings pointed to a service concept that is suggested for a new end-of-life planning service that is suited to Thai Millennials in 4 different groups, which are 1. Social -Conscious as a socially aware who to donate time and riches to make the world and society a better place, their end-of-life planning value is inspired by the social impact of giving something or some action that they will be able to do after life or during life which provides a variety of choice based on their preference to give to society, 2. Life Fulfillment who make a life goal for themselves and attempt to achieve it before the time comes to their value will be to inspire life value with a customized plan and provide guidance to suggest, 3. Prevention of the After-Death Effect who want to plan to avoid the effects of their death as patriarch, head of the family, and anchor of someone, so they want to have a plan that brings confidence and feel relief while they are still alive and they want to find some reliable service that they can leave the death will or asset, and 4. No Guilty Planning who plan for when they wish to be worry-free as a self-responsible they want to have the plan which is easy to understand and easy to access. The overall finding of the study is to understand the new service concept of end-of-life planning which to improve knowledge of significant life worth rather than death planning, encouraging people to reassess their lives in a positive way, leading to higher self-esteem and intrinsic motivation for this generation in this time of global crisis.

Keywords: design management, end-of-life planning, millennial generation, service design solution

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Authors: Hamsa T. Tayeb, Mohammad A. Arafah, Dana M. Bakheet, Duaa M. Khalaf, Agnieszka Tarnoska, Nduna Dzimiri

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Background: CYP2D6 is a member of the cytochrome P450 mixed-function oxidase system. The enzyme is responsible for the metabolism and elimination of approximately 25% of clinically used drugs, especially in breast cancer and psychiatric therapy. Different phenotypes have been described displaying alleles that lead to a complete loss of enzyme activity, reduced function (poor metabolizers – PM), hyperfunctionality (ultrarapid metabolizers–UM) and therefore drug intoxication or loss of drug effect. The prevalence of these variants may vary among different ethnic groups. Furthermore, the xTAG system has been developed to categorized all patients into different groups based on their CYP2D6 substrate metabolization. Aim of the study: To determine the prevalence of the different CYP2D6 variants in our population, and to evaluate their clinical relevance in personalized medicine. Methodology: We used the Luminex xMAP genotyping system to sequence 305 Saudi individuals visiting the Blood Bank of our Institution and determine which polymorphisms of CYP2D6 gene are prevalent in our region. Results: xTAG genotyping showed that 36.72% (112 out of 305 individuals) carried the CYP2D6_*2. Out of the 112 individuals with the *2 SNP, 6.23% had multiple copies of *2 SNP (19 individuals out of 305 individuals), resulting in an UM phenotype. About 33.44% carried the CYP2D6_*41, which leads to decreased activity of the CYP2D6 enzyme. 19.67% had the wild-type alleles and thus had normal enzyme function. Furthermore, 15.74% carried the CYP2D6_*4, which is the most common nonfunctional form of the CYP2D6 enzyme worldwide. 6.56% carried the CYP2D6_*17, resulting in decreased enzyme activity. Approximately 5.73% carried the CYP2D6_*10, consequently decreasing the enzyme activity, resulting in a PM phenotype. 2.30% carried the CYP2D6_*29, leading to decreased metabolic activity of the enzyme, and 2.30% carried the CYP2D6_*35, resulting in an UM phenotype, 1.64% had a whole-gene deletion CYP2D6_*5, thus resulting in the loss of CYP2D6 enzyme production, 0.66% carried the CYP2D6_*6 variant. One individual carried the CYP2D6_*3(B), producing an inactive form of the enzyme, which leads to decrease of enzyme activity, resulting in a PM phenotype. Finally, one individual carried the CYP2D6_*9, which decreases the enzyme activity. Conclusions: Our study demonstrates that different CYP2D6 variants are highly prevalent in ethnic Saudi Arabs. This finding sets a basis for informed genotyping for these variants in personalized medicine. The study also suggests that xTAG is an appropriate procedure for genotyping the CYP2D6 variants in personalized medicine.

Keywords: CYP2D6, hormonal breast cancer, pharmacogenetics, polymorphism, psychiatric treatment, Saudi population

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Authors: Pooja Verma, Rajnesh Tyagi, Sunil Mohan

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Al-Si alloys are widely used in various components such as liner-less engine blocks, piston, compressor bodies and pumps for automobile sector and aerospace industries due to their excellent combination of properties like low thermal expansion coefficient, low density, excellent wear resistance, high corrosion resistance, excellent cast ability, and high hardness. The low density and high hardness of primary Si phase results in significant reduction in density and improvement in wear resistance of hypereutectic Al-Si alloys. Keeping in view of the industrial importance of the alloys, hypereutectic Al-Si alloys containing 14, 16, 18 and 20 wt. % of Si were prepared in a resistance furnace using adequate amount of deoxidizer and degasser and their erosion behavior was evaluated by conducting tests at impingement angles of 30°, 60°, and 90° with an erodent discharge rate of 7.5 Hz, pressure 1 bar using erosion test rig. Microstructures of the cast alloys were examined using Optical microscopy (OM) and scanning electron microscopy (SEM) and the presence of Si particles was confirmed by x-ray diffractometer (XRD). The mechanical properties and hardness were measured using uniaxial tension tests at a strain rate of 10-3/s and Vickers hardness tester. Microstructures of the alloys and X-ray examination revealed the presence of primary and eutectic Si particles in the shape of cuboids or polyhedral and finer needles. Yield strength (YS), ultimate tensile strength (UTS), and uniform elongation of the hypereutectic Al-Si alloys were observed to increase with increasing content of Si. The optimal strength and ductility was observed for Al-20 wt. % Si alloy which is significantly higher than the Al-14 wt. % Si alloy. The increased hardness and the strength of the alloys with increasing amount of Si has been attributed presence of Si in the solid solution which creates strain, and this strain interacts with dislocations resulting in solid-solution strengthening. The interactions between distributed primary Si particles and dislocations also provide Orowan strengthening leading to increased strength. The steady state erosion rate was found to decrease with increasing angle of impact as well as Si content for all the alloys except at 900 where it was observed to increase with the increase in the Si content. The minimum erosion rate is observed in Al-20 wt. % Si alloy at 300 and 600 impingement angles because of its higher hardness in comparison to other alloys. However, at 90° impingement angle the wear rate for Al-20 wt. % Si alloy is found to be the minimum due to deformation, subsequent cracking and chipping off material.

Keywords: Al-Si alloy, erosion wear, cast alloys, dislocation, strengthening

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Authors: Victor V. Ribeiro, Thais C. Lopes, Rafael A. A. Monteiro

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The Albatroz, Baleia Jubarte, Coral Vivo, Golfinho Rotador and Tamar projects make up the Young Sea Network (YSN), part of the BIOMAR Network, which aims to integrate the environmental youths of the Brazilian coast. For this, three editions of the Young Sea Meeting (YSM) were performed. Seeking to stimulate belonging, self-knowledge, participation, autonomy and youth protagonism, the Albatroz Project hosted the III YSM, in Bertioga (SP), in April 2019 and aimed to collectively plan the meeting. Five pillars of Environmental Education were used: identity, community, dialogue, power to act and happiness, the OCA Method and the Young Educates Young; Young Chooses Young; and One Generation Learns from the Other principals. In December 2018, still in the II YSM, the participatory planning of the III YSM began. Two "representatives" of each group were voluntarily elected to facilitate joint decisions, propose, receive and communicate demands from their groups and coordinators. The Young Albatroz Collective (YAC) facilitated the organization process as a whole. The purpose of the meeting was collectively constructed, answering the following question: "What is the YSM for?". Only two of the five pairs of representatives responded. There was difficulty gathering the young people in each group, because it was the end of the year, with people traveling. Thus, due to the short planning time, the YAC built a pre-programming to be validated by the other groups, defining as the objective of the meeting the strengthening of youth protagonism within the YSN. In the planning process, the YAC held 20 meetings, with 60 hours of face-to-face work, in three months, and two technical visits to the headquarters of the III YSM. The participatory dynamics of consultation, when it occurred, required up to two weeks, evidencing the limits of participation. The project coordinations stated that they were not being included in the process by their young people. There is a need to work more to be able to aloud the participation, developing skills and understanding about its principles. This training must take place in an articulated way between the network, implying the important role of the five projects in jointly developing and implementing educator processes with this objective in a national dimension, but without forgetting the specificities of each young group. Finally, it is worth highlighting the great potential of the III YSM by stimulating the exercise of leading environmental youth in more than 50 young people from Brazilian coast, linked to the YSN, stimulating the learning and mobilization of young people in favor of coastal and marine conservation.

Keywords: Marine Conservation, Environmental Education, Youth, Participation, Planning

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Authors: Hoa Pham

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The literature on language teaching and second language acquisition has been largely driven by monolingual ideology with a common assumption that a second language (L2) is best taught and learned in the L2 only. The current study challenges this assumption by reporting learners' positive perceptions of tertiary level teachers' code switching practices in Vietnam. The findings of this study contribute to our understanding of code switching practices in language classrooms from a learners' perspective. Data were collected from student participants who were working towards a Bachelor degree in English within the English for Business Communication stream through the use of focus group interviews. The literature has documented that this method of interviewing has a number of distinct advantages over individual student interviews. For instance, group interactions generated by focus groups create a more natural environment than that of an individual interview because they include a range of communicative processes in which each individual may influence or be influenced by others - as they are in their real life. The process of interaction provides the opportunity to obtain the meanings and answers to a problem that are "socially constructed rather than individually created" leading to the capture of real-life data. The distinct feature of group interaction offered by this technique makes it a powerful means of obtaining deeper and richer data than those from individual interviews. The data generated through this study were analysed using a constant comparative approach. Overall, the students expressed positive views of this practice indicating that it is a useful teaching strategy. Teacher code switching was seen as a learning resource and a source supporting language output. This practice was perceived to promote student comprehension and to aid the learning of content and target language knowledge. This practice was also believed to scaffold the students' language production in different contexts. However, the students indicated their preference for teacher code switching to be constrained, as extensive use was believed to negatively impact on their L2 learning and trigger cognitive reliance on the L1 for L2 learning. The students also perceived that when the L1 was used to a great extent, their ability to develop as autonomous learners was negatively impacted. This study found that teacher code switching was supported in certain contexts by learners, thus suggesting that there is a need for the widespread assumption about the monolingual teaching approach to be re-considered.

Keywords: codeswitching, L1 use, L2 teaching, learners’ perception

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Authors: Antoine Villa, Moustapha Mohamedou, Florence Pilliere, Catherine Verdun-Esquer, Mathieu Molimard, Mohamed Sidatt Cheikh El Moustaph, Mireille Canal-Raffin

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Context: In Mauritania, the activity of the National Center of Oncology (NCO) has steadily risen leading to an increase in the handling of antineoplastic drugs (AD) by healthcare professionals. In this context, the AD contamination of those professionals is a major concern for occupational physicians. It has been evaluated using biological monitoring of occupational exposure (BMOE). Methods: The intervention took place in 2015, in 2 care units, and evaluated nurses preparing and/or infusing AD and agents in charge of hygiene. Participants provided a single urine sample, at the end of the week, at the end of their shift. Five molecules were sought using specific high sensitivity methods (UHPLC-MS/MS) with very low limits of quantification (LOQ) (cyclophosphamide (CP), Ifosfamide (IF), methotrexate (MTX): 2.5ng/L; doxorubicin (Doxo): 10ng/L; α-fluoro-β-alanine (FBAL, 5-FU metabolite): 20ng/L). A healthcare worker was considered as 'contaminated' when an AD was detected at a urine concentration equal to or greater than the LOQ of the analytical method or at trace concentration. Results: Twelve persons participated (6 nurses, 6 agents in charge of hygiene). Twelve urine samples were collected and analyzed. The percentage of contamination was 66.6% for all participants (n=8/12), 100% for nurses (6/6) and 33% for agents in charge of hygiene (2/6). In 62.5% (n=5/8) of the contaminated workers, two to four of the AD were detected in the urine. CP was found in the urine of all contaminated workers. FBAL was found in four, MTX in three and Doxo in one. Only IF was not detected. Urinary concentrations (all drugs combined) ranged from 3 to 844 ng/L for nurses and from 3 to 44 ng/L for agents in charge of hygiene. The median urinary concentrations were 87 ng/L, 15.1 ng/L and 4.4 ng/L for FBAL, CP and MTX, respectively. The Doxo urinary concentration was found 218ng/L. Discussion: There is no current biological exposure index for the interpretation of AD contamination. The contamination of these healthcare professionals is therefore established by the detection of one or more AD in urine. These urinary contaminations are higher than the LOQ of the analytical methods, which must be as low as possible. Given the danger of AD, the implementation of corrective measures is essential for the staff. Biological monitoring of occupational exposure is the most reliable process to identify groups at risk, tracing insufficiently controlled exposures and as an alarm signal. These results show the necessity to educate professionals about the risks of handling AD and/or to care for treated patients.

Keywords: antineoplastic drugs, Mauritania, biological monitoring of occupational exposure, contamination

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Authors: Anvesh Gaddam, Amit Agrawal, Suhas Joshi, Mark Thompson

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An increase in surface area to volume ratio with a decrease in characteristic length scale, leads to a rapid increase in pressure drop across the microchannel. Texturing the microchannel surfaces reduce the effective surface area, thereby decreasing the pressured drop. Surface texturing introduces two wetting states: a metastable Cassie-Baxter state and stable Wenzel state. Predicting wetting transition in textured microchannels is essential for identifying optimal parameters leading to maximum drag reduction. Optical methods allow visualization only in confined areas, therefore, obtaining whole-field information on wetting transition is challenging. In this work, we propose a non-invasive method to capture wetting transitions in textured microchannels under flow conditions. To this end, we tracked the behavior of the Poiseuille number Po = f.Re, (with f the friction factor and Re the Reynolds number), for a range of flow rates (5 < Re < 50), and different wetting states were qualitatively demarcated by observing the inflection points in the f.Re curve. Microchannels with both longitudinal and transverse ribs with a fixed gas fraction (δ, a ratio of shear-free area to total area) and at a different confinement ratios (ε, a ratio of rib height to channel height) were fabricated. The measured pressure drop values for all the flow rates across the textured microchannels were converted into Poiseuille number. Transient behavior of the pressure drop across the textured microchannels revealed the collapse of liquid-gas interface into the gas cavities. Three wetting states were observed at ε = 0.65 for both longitudinal and transverse ribs, whereas, an early transition occurred at Re ~ 35 for longitudinal ribs at ε = 0.5, due to spontaneous flooding of the gas cavities as the liquid-gas interface ruptured at the inlet. In addition, the pressure drop in the Wenzel state was found to be less than the Cassie-Baxter state. Three-dimensional numerical simulations confirmed the initiation of the completely wetted Wenzel state in the textured microchannels. Furthermore, laser confocal microscopy was employed to identify the location of the liquid-gas interface in the Cassie-Baxter state. In conclusion, the present method can overcome the limitations posed by existing techniques, to conveniently capture wetting transition in textured microchannels.

Keywords: drag reduction, Poiseuille number, textured surfaces, wetting transition

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Authors: Ässia Boukhatmi, Roger Nyffenegger

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The expansion of solar energy as a means to address the climate crisis is undisputed, but the increasing number of new photovoltaic (PV) modules being put on the market is simultaneously leading to increased challenges in terms of managing the growing waste stream. Many of the discarded modules are still fully functional but are often damaged by improper handling after disassembly or not properly tested to be considered for a second life. In addition, the collection rate for dismantled PV modules in several European countries is only a fraction of previous projections, partly due to the increased number of illegal exports. The underlying problem for those market imperfections is an insufficient data exchange between the different actors along the PV value chain, as well as the limited traceability of PV panels during their lifetime. As part of the Horizon 2020 project CIRCUSOL, an asset database prototype was developed to tackle the described problems. In an iterative process applying the design science research methodology, different business models, as well as the technical implementation of the database, were established and evaluated. To explore the requirements of different stakeholders for the development of the database, surveys and in-depth interviews were conducted with various representatives of the solar industry. The proposed database prototype maps the entire value chain of PV modules, beginning with the digital product passport, which provides information about materials and components contained in every module. Product-related information can then be expanded with performance data of existing installations. This information forms the basis for the application of data analysis methods to forecast the appropriate end-of-life strategy, as well as the circular economy potential of PV modules, already before they arrive at the recycling facility. The database prototype could already be enriched with data from different data sources along the value chain. From a business model perspective, the database offers opportunities both in the area of reuse as well as with regard to the certification of sustainable modules. Here, participating actors have the opportunity to differentiate their business and exploit new revenue streams. Future research can apply this approach to further industry and product sectors, validate the database prototype in a practical context, and can serve as a basis for standardization efforts to strengthen the circular economy.

Keywords: business model, circular economy, database, design science research, solar industry

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Authors: Fereshteh Ganjavi, Rachel Schaffer, Varsha Jorawar

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Elena’s Light is a non-profit organization focused on building brighter futures for refugees, especially women and children. Our mission is to empower refugee women and children by addressing social, legal, and public health issues that predominantly concern them. Elena’s Light offers a range of services that support refugees from structural disadvantages, cultural and social stress, marginalization, and other stressors related to migration. Using a three-pronged approach, our programs focus on legal advocacy, English language acquisition, and health and wellness. Following the Afghan humanitarian crisis, Elena’s Light has developed and intensified advocacy efforts in the legal realm to address the influx of refugees who desperately need assistance. We developed and hosted a Know Your Rights presentation with local immigration lawyers and professionals in February 2022 on the Afghan Humanitarian Parole, which was very successful with over 100 attendees. Elena’s Light is hosting the second Know Your Rights session in early August 2022 on immigration options for Afghans, including Temporary Protected Status (TPS), asylum, Special Immigrant Visa (SIV), and humanitarian parole. Lastly, EL is also leading the local initiative to develop a pro-bono committee to respond to the overwhelming need for lawyers to work on legal cases for Afghan during this crisis. Furthermore, through our other services, we provide free, in-home customizable ESL tutoring sessions to refugee women with a focus on driver’s education, facilitating acculturation, and improving employment opportunities. We also provide in-home maternal, pediatric, and mental health education and wellness services that are aimed at addressing the explicit and implicit barriers to healthcare for refugee populations. Elena’s Light’s diverse community aims to counter the structural disadvantages and anxiety-inducing emotions and experiences related to being a refugee. We would like to join this International Conference on Refugee Law since protecting refugee rights is our mission. We would like to share what we have learned from our legal initiatives for refugee rights. We would also like to listen, learn from, and discuss with experts and researchers how to better understand and advocate for refugee rights. We hope to improve our understanding of how to provide better legal aid for our clients through this conference.

Keywords: legal, advocacy, Afghan humanitarian crisis, policy, pro-bono

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Authors: Kamrun Nahar Koly, Saimul Islam

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Overweight and obesity is increasing at an alarming rate and a leading risk factor for morbidity throughout the world. In a country like Bangladesh where under nutrition and overweight both co-exist at the same time, but this issue has been underexplored as expected. The aim of the present study was to assess the knowledge, attitudes and identify the barriers of the physicians regarding overweight and obesity management on an urban hospital of Dhaka city in Bangladesh. A simple cross sectional study was conducted at two selected government and two private hospital to assess the knowledge, attitude and common barriers regarding overweight and obesity management among healthcare professionals. One hundred and fifty five physicians were surveyed. A standard questionnaire was constructed in local language and interview was administrated. Among the 155 physicians, majority 53 (34.20%) were working on SMC, 36 (23.20%) from DMC, 33 (21.30%) were based on SSMC and the rest 33 (21.30%) were from HFRCMH. Mean age of the study physicians were 31.88±5.92. Majority of the physicians 80 (51.60%) were not able to answer the correct prevalence of obesity but also a substantial number of them 75(48.40%) could mark the right answer. Among the physicians 150 (96.77%) reported BMI as a diagnostic index for overweight and obesity, where as 43 (27.74%) waist circumference, 30 (19.35%) waist hip ratio and 26 (16.77%) marked mid-arm circumference. A substantial proportion 71 (46.70%) of the physicians thought that they do not have much to do controlling weight problem in Bangladesh context though it has been opposed by 42 (27.60%) of the physicians and 39(25.70%) was neutral to comment. The majority of them 147 (96.1%) thought that a family based education program would be beneficial followed by 145 (94.8%) physicians mentioned about raising awareness among mothers as she is the primary caregiver. The idea of a school based education program will also help to early intervene referred by 142 (92.8%) of the physicians. Community based education program was also appreciated by 136 (89.5%) of the physicians. About 74 (47.7%) of them think that the patients still lack in motivation to maintain their weight properly at the same time too many patients to deal with can be a barrier as well assumed by 73 (47.1%) of them. Lack of national policy or management guideline can act as an obstacle told by 60 (38.7%) of the physicians. The relationship of practicing as a part of the general examination and chronic disease management was statistically significant (p<0.05) with physician occupational status. As besides, perceived barriers like lack of parents support, lack of a national policy was statistically significant (p<0.05) with physician occupational status. For the young physician, more training programme will be needed to transform their knowledge and attitude into practice. However, several important barriers interface for the physician treatment efforts and need to address.

Keywords: obesity management, physician, awareness, barriers, Bangladesh

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Authors: Onur Ozveri, Korkut Karabag, Cagri Keles

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It is an important issue that the occurring of production downtime and repair costs when machines fail in the machine intensive production industries. In the case of failure of more than one machine at the same time, which machines will have the priority to repair, how to determine the optimal repair time should be allotted for this machines and how to plan the resources needed to repair are the key issues. In recent years, Business Process Management (BPM) technique, bring effective solutions to different problems in business. The main feature of this technique is that it can improve the way the job done by examining in detail the works of interest. In the industries, maintenance and repair works are operating as a process and when a breakdown occurs, it is known that the repair work is carried out in a series of process. Maintenance main-process and repair sub-process are evaluated with process management technique, so it is thought that structure could bring a solution. For this reason, in an international manufacturing company, this issue discussed and has tried to develop a proposal for a solution. The purpose of this study is the implementation of maintenance and repair works which is integrated with process management technique and at the end of implementation, analyzing the maintenance related parameters like quality, cost, time, safety and spare part. The international firm that carried out the application operates in a free region in Turkey and its core business area is producing original equipment technologies, vehicle electrical construction, electronics, safety and thermal systems for the world's leading light and heavy vehicle manufacturers. In the firm primarily, a project team has been established. The team dealt with the current maintenance process again, and it has been revised again by the process management techniques. Repair process which is sub-process of maintenance process has been discussed again. In the improved processes, the ABC equipment classification technique was used to decide which machine or machines will be given priority in case of failure. This technique is a prioritization method of malfunctioned machine based on the effect of the production, product quality, maintenance costs and job security. Improved maintenance and repair processes have been implemented in the company for three months, and the obtained data were compared with the previous year data. In conclusion, breakdown maintenance was found to occur in a shorter time, with lower cost and lower spare parts inventory.

Keywords: ABC equipment classification, business process management (BPM), maintenance, repair performance

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Authors: Qingqing Feng, S. Thomas Ng, Frank J. Xu, Jiduo Xing

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Faced with unprecedented challenges including aging assets, lack of maintenance budget, overtaxed and inefficient usage, and outcry for better service quality from the society, today’s infrastructure systems has become the main focus of many metropolises to pursue sustainable urban development and improve resilience. Digital twin, being one of the most innovative enabling technologies nowadays, may open up new ways for tackling various infrastructure asset management (IAM) problems. Digital twin application for IAM, as its name indicated, represents an evolving digital model of intended infrastructure that possesses functions including real-time monitoring; what-if events simulation; and scheduling, maintenance, and management optimization based on technologies like IoT, big data and AI. Up to now, there are already vast quantities of global initiatives of digital twin applications like 'Virtual Singapore' and 'Digital Built Britain'. With digital twin technology permeating the IAM field progressively, it is necessary to consider the maturity of the application and how those institutional or industrial digital twin application processes will evolve in future. In order to deal with the gap of lacking such kind of benchmark, a draft maturity model is developed for digital twin application in the IAM field. Firstly, an overview of current smart cities maturity models is given, based on which the draft Maturity Model of Digital Twin Application for Infrastructure Asset Management (MM-DTIAM) is developed for multi-stakeholders to evaluate and derive informed decision. The process of development follows a systematic approach with four major procedures, namely scoping, designing, populating and testing. Through in-depth literature review, interview and focus group meeting, the key domain areas are populated, defined and iteratively tuned. Finally, the case study of several digital twin projects is conducted for self-verification. The findings of the research reveal that: (i) the developed maturity model outlines five maturing levels leading to an optimised digital twin application from the aspects of strategic intent, data, technology, governance, and stakeholders’ engagement; (ii) based on the case study, levels 1 to 3 are already partially implemented in some initiatives while level 4 is on the way; and (iii) more practices are still needed to refine the draft to be mutually exclusive and collectively exhaustive in key domain areas.

Keywords: digital twin, infrastructure asset management, maturity model, smart city

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Authors: Seyeon Lee, Suyeon Lee, Julia Rogers

Abstract:

This research investigates and records post-flood and typhoon conditions of low income housing in the Thua Thien Hue Province, Vietnam; area prone to extreme flooding in Central Vietnam. The cost of rebuilding houses after flood and typhoon has been always a burden for low income households. These costs often lead to the elimination of essential construction practices for disaster resistance. Despite relief efforts from international non-profit organizations and Vietnam government, the impacts of flood and typhoon damages to residential construction has been reoccurring to the same neighborhood annually. Notwithstanding its importance, this topic has not been systematically investigated. The study is limited to assistance provided to low income households documenting existing conditions of low income homes impacted by post flood and typhoon conditions in the Thua Thien Hue Province. The research identifies leading causes of the building failure from the natural disasters. Relief efforts and progress made since the last typhoon is documented. The quality of construction and repairs are assessed based on Home Builders Guide to Coastal Construction by Federal Emergency Management Agency. Focus group discussions and individual interviews with local residents from four different communities were conducted to get incites on repair effort by the non-profit organizations and Vietnam government, and their needs post flood and typhoon. The findings from the field study informed that many of the local people are now aware of the importance of improving housing conditions as one of the key coping strategies to withstand flood and typhoon events as it makes housing and community more resilient to future events. While there has been a remarkable improvement of housing and infrastructure with the support from the local government as well as the non-profit organizations, many households in the study areas are found to still live in weak and fragile housing conditions without gaining access to the aid to repair and strengthen the houses. Given that the major immediate recovery action taken by the local people tends to focus on repairing damaged houses, and on this ground, low-income households spend a considerable amount of their income on housing repair, providing proper and applicable construction practices will not only improve the housing condition, but also contribute to reducing poverty in Vietnam.

Keywords: disaster coping mechanism, housing welfare, low-income housing, recovery reduction

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