Search results for: focus group interview

Authors: Tabbye Chavous, Felecia Webb, Bridget Richardson, Gloryvee Fonseca-Bolorin, Seanna Leath, Robert Sellers

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There has been recent renewed attention to Black students’ experiences at predominantly White U.S. universities (PWIs), e.g., the #BBUM (“Being Black at the University of Michigan”), “I too am Harvard” social media campaigns, and subsequent student protest activities nationwide. These campaigns illuminate how many minority students encounter challenges to their racial/ethnic identities as they enter PWI contexts. Students routinely report experiences such as being ignored or treated as a token in classes, receiving messages of low academic expectations by faculty and peers, being questioned about their academic qualifications or belonging, being excluded from academic and social activities, and being racially profiled and harassed in the broader campus community due to race. Researchers have linked such racial marginalization and stigma experiences to student motivation and achievement. One potential mechanism is through the impact of college experiences on students’ identities, given the relevance of the college context for students’ personal identity development, including personal beliefs systems around social identities salient in this context. However, little research examines the impact of the college context on Black students’ racial identities. This study examined change in Black college students’ (N=329) racial identity beliefs over the freshman year at three predominantly White U.S. universities. Using cluster analyses, we identified profile groups reflecting different patterns of stability and change in students’ racial centrality (importance of race to overall self-concept), private regard (personal group affect/group pride), and public regard (perceptions of societal views of Blacks) from beginning of year (Time 1) to end of year (Time 2). Multinomial logit regression analyses indicated that the racial identity change clusters were predicted by pre-college background (racial composition of high school and neighborhood), as well as college-based experiences (racial discrimination, interracial friendships, and perceived campus racial climate). In particular, experiencing campus racial discrimination related to high, stable centrality, and decreases in private regard and public regard. Perceiving racial climates norms of institutional support for intergroup interactions on campus related to maintaining low and decreasing in private and public regard. Multivariate Analyses of Variance results showed change cluster effects on achievement motivation outcomes at the end of students’ academic year. Having high, stable centrality and high private regard related to more positive outcomes overall (academic competence, positive academic affect, academic curiosity and persistence). Students decreasing in private regard and public regard were particularly vulnerable to negative motivation outcomes. Findings support scholarship indicating both stability in racial identity beliefs and the importance of critical context transitions in racial identity development and adjustment outcomes among emerging adults. Findings also are consistent with research suggesting promotive effects of a strong, positive racial identity on student motivation, as well as research linking awareness of racial stigma to decreased academic engagement.

Keywords: diversity, motivation, learning, ethnic minority achievement, higher education

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Authors: C. Morris, W. Ashall, K. Telling, L. Kadiwal, J. Kirby, S. Mwale

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This paper addresses experiences of liminality in the early career phase of academia. Liminality is understood as a process moving from one state (in this case of being non-academic) to another (of being academic), caught between or moving in and out these modes of being. Drawing on life-history methods, a group of academics jointly reflected on experiences of the early career. Primarily focused on the theme of imposter syndrome at this career stage, the authors identified feelings of non-belonging and lack of fit with the academy, tracing the biographical, political, and affective dimensions of such responses. Uncertainty around status within seemingly impermeable hierarchies and barriers to progression in combination with our intersectional positionings shaped by sexism, racism, ableism, and classism, led to experiences of liminality, having not yet fully achieved the desired and potentially illusionary status of established academic. Findings are contextualised within the authors’ contrasting disciplinary, departmental, and institutional settings against a backdrop of neoliberalised academia. The paper thereby contributes nuanced understandings of early-career academic identities at a time when this career stage is ever more ill-defined, extended, precarious and uncertain, exposing ongoing impacts of inequities in the contemporary academic milieu.

Keywords: early career, identities, intersectionality, liminality

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Authors: M. Devamanalan, K. Pothiraj, M. Sudhan

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In competitive market like India, there is a high demand on the equal contribution on performance and its durability aspect of any system. In General vehicle has multiple sub-systems such as powertrain, BIW, Brakes, Actuations, Suspension and Seats etc., To withstand the market challenges, the contribution of each sub-system is very vital. The malfunction of any one sub system will directly have an impact on the performance of the major system which lead to dis-satisfaction to the end user. The Powertrain system consists of several sub-systems in which clutch is one of the prime sub-systems in MT vehicles which assist for smoother gear shifts with proper clutch dis-engagement and engagement. In general, most of the vehicles will have a mechanical or semi or full hydraulic clutch release system, whereas in small Commercial Vehicles (SCV) the majorly used clutch release system is mechanical cable release system due to its lesser cost and functional requirements. The major bottle neck in the cable type clutch release system is increase in pedal effort due to hysteresis increase and Gear shifting hard due to efficiency loss / cable slackness over the mileage accumulation of the vehicle. This study is to mainly focus on how the efficiency and hysteresis change over the mileage of the vehicle occurs because of the design architecture of outer and inner cable. The study involves several cable design validation results from vehicle level and rig level through the defined cable routing and test procedures. Results are compared to evaluate the suitable cable design architecture based on better efficiency and lower hysteresis parameters at initial and end of the validation.

Keywords: clutch, clutch cable, efficiency, architecture, cable routing

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Authors: Aarti Singh, Anees Ahmad

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Carotenoids comprise a group of isoprenoid pigments. Carotenes, xanthophylls and their derivatives have been found to play an important role in all living beings through foods, neutraceuticals and pharmaceuticals. α-carotene, β-carotene and β-cryptoxanthin play a vital role in humans to provide vitamin A source for the growth, development and proper functioning of immune system and vision. They are very crucial for plants and humans as they protect from photooxidative damage and are excellent antioxidants quenching singlet molecular oxygen and peroxyl radicals. Diet including more intake of carotenoids results in reduced threat of various chronic diseases such as cancer (lung, breast, prostate, colorectal and ovarian cancers) and coronary heart diseases. The blue light filtering efficiency of the carotenoids in liposomes have been reported to be maximum in lutein followed by zeaxanthin, β-carotene and lycopene. Lycopene play a vital role for the protection from CVD. Lycopene in serum is directly related to reduced risk of osteoporosis in postmenopausal women. Carotenoids have the major role in the treatment of skin disorders. There is a need to identify and isolate novel carotenoids from diverse natural sources for human health benefits.

Keywords: antioxidants, carotenoids, neutraceuticals, osteoporosis, pharmaceuticals

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Authors: Hanan Abufares Elkhimry

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Looking for more effective teaching and learning approaches, teaching instructors have been telling trainee teachers to decrease their talking time, but the problem is how best to do this. Doing classroom research, specifically in the area of teacher talking time (TTT), is worthwhile, as it could improve the quality of teaching languages, as the learners are the ones who should be practicing and using the language. This work hopes to ascertain if teachers consider this need in a way that provides the students with the opportunities to increase their production of language. This is a question that is worthwhile answering. As many researchers have found, TTT should be decreased to 30% of classroom talking time and STT should be increased up to 70%. Other researchers agree with this, but add that it should be with awareness of the quality of teacher talking time. Therefore, this study intends to investigate the balance between quantity and quality of teacher talking time in the EFL classroom. For this piece of research and in order to capture the amount of talking in a four classrooms. The amount of talking time was measured. A Checklist was used to assess the quality of the talking time In conclusion, In order to improve the quality of TTT, the results showed that teachers may use more or less than 30% of the classroom talking time and still produce a successful classroom learning experience. As well as, the important factors that can affect TTT is the English level of the students. This was clear in the classroom observations, where the highest TTT recorded was with the lowest English level group.

Keywords: teacher talking time TTT, learning experience, classroom research, effective teaching

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Authors: Elaine Wong Yee-Sing

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Older adults are at high risk of chronic health conditions in Singapore. A closer examination at all facets of their aging process has revealed that they may not be necessary aging well. This demands for an increasing healthcare services brought to their home environment due to limited mobility and in the interest of time management. The home environment is an ideal setting to implement self-directed health promoting activities at their convenience and enable family’s support and motivation. This research protocol aims to explore their healthcare concerns, and creation of age appropriate interventions targeted to improve their chronic disease biomarkers. Convenience sampling of 130 families residing in private housing within five major districts in Singapore will be selected to participate in the health intervention. Statistical Package for Social Science 25 will be used to examine the pre and post screening results of their lipid, glycaemia and anthropometric outcomes. Using focus interviews, data results will be translated and transcribed to investigate on enablers, barriers and improvement on these services. Both qualitative and quantitative research outcomes are crucial to examine the impact of these services for these older adults living in private housing as they are not exposed to government subsidized community health programs. It is hypothesized that provision of relevant yet engaging health programs at their homes may mitigate the rising burden of chronic health conditions and result in successful aging outcomes among older Singaporeans.

Keywords: chronic diseases, health program, older adults, residential homes

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Authors: Xinchen Zhu

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In the history of Chinese-language film, female stars’ acting is connected with issues of national ideology, consumerism, and sexual politics. In the 1980s, Taiwan entered a period of ‘soft authoritarianism’ in which the economy prospered politics became more democratic, and mass culture became more diverse. Film censorship was more flexible and sexual scenes were increasingly shown on screen. Female stars’ bodies were eroticized and commercialized through sexual and nude scenes and, by challenging conservative film censorship and social taboos, became the focus of mass media. This article will explore how discourses in mass media constructed the erotic images of female stars and, conversely, impacted film censorship, filmmakers and film actresses in 1980s’ Taiwan. This article will regard the eroticized female film stars’ acting as a ‘field’ of internal interaction and continuous reproduction, where the ideology of male dominance and voices of female film stars conflict with each other. Based on textual analysis of female stars’ sexual acting and the debate in mass media, the argument is that the eroticized female bodies were gazed upon on and off the screen. In the discourses of mass media, the artistry of actresses’ erotic acting was not only ignored, devalued and delegitimized, these stars were also labelled as ‘undressed star’ or ‘nude star’ and construed as victims of the film industry. However, the female stars were able to speak through mass media platforms, emphasizing their efforts in erotic acting and highlighting modern female subjectivity.

Keywords: sexual scenes, Taiwan female stars, erotic acting, discourses in mass media, female subjectivity

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Authors: Rafael Sousa Santos, Clara Pimena Do Vale, Barbara Bogoni, Poul Henning Kirkegaard

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The representative component, a determining aspect of the architect's training, has been marked by an exponential and unprecedented development. However, the multiplication of possibilities has also multiplied uncertainties about architectural design teaching, and by extension, about the very principles of architectural education. In this paper, it is intended to present the results of a research developed on the following problem: the relation between the forms of representation and the architectural design teaching-learning processes. The research had as its object the educational model of two schools – the Politecnico di Milano (POLIMI) and the Faculty of Architecture of the University of Porto (FAUP) – and was led by three main objectives: to characterize the educational model followed in both schools focused on the representative component and its role; to interpret the relation between forms of representation and the architectural design teaching-learning processes; to consider their possibilities of valorisation. Methodologically, the research was conducted according to a qualitative embedded multiple-case study design. The object – i.e., the educational model – was approached in both POLIMI and FAUP cases considering its Context and three embedded unities of analysis: the educational Purposes, Principles, and Practices. In order to guide the procedures of data collection and analysis, a Matrix for the Characterization (MCC) was developed. As a methodological tool, the MCC allowed to relate the three embedded unities of analysis with the three main sources of evidence where the object manifests itself: the professors, expressing how the model is assumed; the architectural design classes, expressing how the model is achieved; and the students, expressing how the model is acquired. The main research methods used were the naturalistic and participatory observation, in-person-interview and documentary and bibliographic review. The results reveal the importance of the representative component in the educational model of both cases, despite the differences in its role. In POLIMI's model, representation is particularly relevant in the teaching of architectural design, while in FAUP’s model, it plays a transversal role – according to an idea of 'general training through hand drawing'. In fact, the difference between models relative to representation can be partially understood by the level of importance that each gives to hand drawing. Regarding the teaching of architectural design, the two cases are distinguished in the relation with the representative component: while in POLIMI the forms of representation serve essentially an instrumental purpose, in FAUP they tend to be considered also for their methodological dimension. It seems that the possibilities for valuing these models reside precisely in the relation between forms of representation and architectural design teaching. It is expected that the knowledge base developed in this research may have three main contributions: to contribute to the maintenance of the educational model of POLIMI and FAUP; through the precise description of the methodological procedures, to contribute by transferability to similar studies; through the critical and objective framework of the problem underlying the forms of representation and its relation with architectural design teaching, to contribute to the broader discussion concerning the contemporary challenges on architectural education.

Keywords: architectural design teaching, architectural education, educational models, forms of representation

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Authors: K. M. Saif Ur Rahman, Razib Mamun, Himica Arjuman, Fida Al Shams

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Introduction: Autism spectrum disorder (ASD) has become an emerging neurodevelopmental disorder with increasing prevalence. It has become an important public health issue globally. Many approaches including speech and language therapy (SLT), occupational therapy, behavioral therapy etc. are being applied for the betterment of the ASD patients. This study aims to describe the characteristics of ASD patients and perception of caregiver regarding SLT in Bangladesh. Methods: This cross-sectional study was conducted in a therapy and rehabilitation center at Dhaka city. Caregivers of 48 ASD patients responded regarding their perception of SLT and characteristics of patients. Results: Among 48 ASD patients, 56.3% were between 3 to 5 years age group with a male predominance (87.5%). More than half of the participants (56.3%) initiated SLT at the age of 1-3 years and the majority (43.8%) were taking SLT for less than 1 year. Majority of the patients (64.6%) were taken to a physician for healthcare as a first contact of which 29.2% were referred to SLT by physicians. More than half (56.3%) of the caregivers were moderately satisfied with SLT and most of them (62.5%) mentioned moderate improvement through SLT. Improvement rate was 10-15% in specific symptoms such as eye contact, complex mannerism, pointing, imitation etc. Conclusion: This study reveals the self-reported perception of caregivers on SLT. Despite reported improvements, more exploration of different approaches and intervention for management of ASD is recommended.

Keywords: ASD, characteristics, SLT, Bangladesh

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Authors: Münevver Başman, Ezel Tavşancıl

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Making the right decisions about students depends on teachers’ use of the assessment and evaluation techniques effectively. In order to do that, teachers should have positive attitudes and adequate self-efficacy perception towards assessment and evaluation. The purpose of this study is to investigate relationship between self-efficacy perception and the attitudes of prospective teachers towards assessment and evaluation and what kind of differences these issues have in terms of a variety of demographic variables. The study group consisted of 277 prospective teachers who have been studying in different departments of Marmara University, Faculty of Education. In this study, ‘Personal Information Form’, ‘A Perceptual Scale for Measurement and Evaluation of Prospective Teachers Self-Efficacy in Education’ and ‘Attitudes toward Educational Measurement Inventory’ are applied. As a result, positive correlation was found between self-efficacy perceptions and the attitudes of prospective teachers towards assessment and evaluation. Considering different departments, there is a significant difference between the mean score of attitudes of prospective teachers and between the mean score of self-efficacy perceptions of them. However, considering variables of attending statistics class and the class types at the graduated high school, there is no significant difference between the mean score of attitudes of prospective teachers and between the mean score of self-efficacy perceptions of them.

Keywords: attitude, perception, prospective teacher, self-efficacy

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Authors: Charles Okon Effiong

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This paper is a sociolinguistic analysis of the semantics of students’ slang in Akwa Ibom State College of Education, Afaha Nsit, Nigeria. The descriptive survey design was deployed for the study and data were collected from one hundred and fifty (150) students through a series of instruments such as questionnaire, interviews and observations. The questionnaire was administered randomly to levels 200, 300 and Extra Time students only. Interviews and observations were also conducted on the students. These categories of students were selected because they had spent a longer time in the college and were thought to be familiar with campus slang. A total of ninety two (92) slang expressions were taken from the questionnaire and out of this number, twenty six (26) slang expressions were peculiar to the college while sixty six (66) were those slang terms also used in the society. The study proves the notion that every speaker handles a variety of registers and tends to choose among them in accordance with the social situation in which he finds himself. The study shows campus slang as a sociolect which facilitates communication among the students in a different sense. The slang expressions are fully intelligible to the students and this unique and elaborate lexicon serves to achieve group identity among other social implications.

Keywords: communication, slang, social relationship, sociolinguistics

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Authors: Aelita Skarzauskiene, Monika Maciuliene

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In this paper, we conduct a systematic survey of urban communities in Lithuania to evaluate their potential to co-create collective intelligence or “civic intelligence” applying Digital Co-creation Index methodology that includes different socio-technological indicators. Civic intelligence is a form of collective intelligence that refers to the group’s capacity to perceive societal problems and to address them effectively. The research focuses on evaluation of diverse organizational designs that increase efficient collective performance. The current scientific project advanced the state of the art by evaluating the basic preconditions in the urban communities through which the collective intelligence is being co-created under the systemic manner. The research subject is the “bottom up” digital enabled urban platforms, initiated by Lithuanian public organizations, civic movements or business entities. The web-based monitoring results obtained by applying a social indices calculation methodology and Pearson correlation analysis provided the information about the potential and limits of the urban communities and what possible changes need to be implemented to overcome the limitations.

Keywords: computer supported collaboration, socio-technological system, collective intelligence, networked society

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Authors: Amal A. Qedrah, Sofia A. Malik, Madiha Akbar

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The aim of this article is to share a rare clinical case of pregnancy and surgical delivery in a patient who has undergone augmentation cystoplasty with mitrofanoff channel in the past. Methods: This case report is about a woman who conceived naturally at the age of 27, previously underwent augmentation cystoplasty at the age of 10 years with mitrofanoff procedure using self-clean intermittent catheterization. Furthermore, this pregnancy was complicated by the presence of preeclampsia diagnosed at term and PROM. Following the failure of induction for intrapartum preeclampsia, the patient delivered a healthy baby via low transverse cesarean section at 38 weeks done at Latifa Hospital, Dubai. Conclusion: The procedure is done at a pediatric or young age, after which most patients reach reproductive age. There is no contraindication to pregnancy vaginally or surgically; however, this case was complicated by preeclampsia, due to which this patient was taken for a cesarean section. It is advisable to consult a urologist frequently along with taking regular bacteriological urine samples and blood samples with renal ultrasonography for the evaluation of the kidney. Antibacterial treatment or prophylaxis should be used during pregnancy if necessary and intermittent self-catherization is mostly performed routinely. It is also important to have a urologist on standby during the surgery in order to avoid and/or fix any complications that might come forth.

Keywords: augmentation cystoplasty, cesarean section, delivery, mitrofanoff channel

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Authors: Changju Lee, Seungmo Ku, Sondo Kim, Woojin Chang

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How to detecting financial bubble? Addressing this simple question has been the focus of a vast amount of empirical research spanning almost half a century. However, financial bubble is hard to observe and varying over the time; there needs to be more research on this area. In this paper, we used abnormal difference between common stocks price and those preferred stocks price to explain financial bubble. First, we proposed the ‘W-index’ which indicates spread between common stocks and those preferred stocks in stock market. Second, to prove that this ‘W-index’ is valid for measuring financial bubble, we showed that there is an inverse relationship between this ‘W-index’ and S&P500 rate of return. Specifically, our hypothesis is that when ‘W-index’ is comparably higher than other periods, financial bubbles are added up in stock market and vice versa; according to our hypothesis, if investors made long term investments when ‘W-index’ is high, they would have negative rate of return; however, if investors made long term investments when ‘W-index’ is low, they would have positive rate of return. By comparing correlation values and adjusted R-squared values of between W-index and S&P500 return, VIX index and S&P500 return, and TED index and S&P500 return, we showed only W-index has significant relationship between S&P500 rate of return. In addition, we figured out how long investors should hold their investment position regard the effect of financial bubble. Using this W-index, investors could measure financial bubble in the market and invest with low risk.

Keywords: financial bubble detection, future return, forecasting, pairs trading, preferred stocks

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Authors: Leyla Noroozbabaee, David Nickerson

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We introduce a modular, consistent, reusable bond graph model of the renal nephron’s proximal convoluted tubule (PCT), which can reproduce biological behaviour. In this work, we focus on ion and volume transport in the proximal convoluted tubule of the renal nephron. Modelling complex systems requires complex modelling problems to be broken down into manageable pieces. This can be enabled by developing models of subsystems that are subsequently coupled hierarchically. Because they are based on a graph structure. In the current work, we define two modular subsystems: the resistive module representing the membrane and the capacitive module representing solution compartments. Each module is analyzed based on thermodynamic processes, and all the subsystems are reintegrated into circuit theory in network thermodynamics. The epithelial transport system we introduce in the current study consists of five transport membranes and four solution compartments. Coupled dissipations in the system occur in the membrane subsystems and coupled free-energy increasing, or decreasing processes appear in solution compartment subsystems. These structural subsystems also consist of elementary thermodynamic processes: dissipations, free-energy change, and power conversions. We provide free and open access to the Python implementation to ensure our model is accessible, enabling the reader to explore the model through setting their simulations and reproducibility tests.

Keywords: Bond Graph, Epithelial Transport, Water Transport, Mathematical Modeling

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Authors: Sanghyun Park

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Influenced by the ideas of collectivism, East Asian contemporary dance is marked by an emphasis on unity and synchronization. A growing element of this discipline that disrupts the path that strives to attain perfection, requiring coordination between multiple parties in order to produce work of their highest artistic potential, with the support from individuals or groups is the presence of disabled dancers. Kawanaka Yo, a Japanese dancer with a mental disability, argues through her '“Dance of Peace' that a dancer should focus on her impulses and natural thoughts through improvisational dancing and eschewal of documentation. Professor and poet Jung-Gyu Jeong, co-founder of the Korea Disability International Art Company, demonstrates with his company’s modernized performances of popular works and musicals that disabled artists do not need perfection so long as they can assert their finesse to mimic or create an equivalence with able-bodied dancers. Yo has studied various forms of modern dance and ballet in Japan and has used her training to ease her mental disability but also accept her handicap as an extension of her identity, representing a trend in disabled dance that favors individuality and acceptance. In contrast, Jeong is an influential figure in South Korea for disabled dancers and artists, believing that disabled artists must overcome a certain threshold in order to reach a status as an artist that is equivalent to a 'normal artist.' East Asian art created by the disabled should not be judged according to different criteria or rubrics compared to able-bodied artists because, as Yo explains, a person’s identity and her handicaps characterize the meaning of, and the value of, the piece.

Keywords: disability studies, modern dance, East Asia, politics of identity

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Authors: Irina Khutsishvili

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In the present research, a decision support methodology for the multi-attribute group decision-making (MAGDM) problem is developed, namely for the selection of investment projects. The objective of the investment project selection problem is to choose the best project among the set of projects, seeking investment, or to rank all projects in descending order. The project selection is made considering a set of weighted attributes. To evaluate the attributes in our approach, expert assessments are used. In the proposed methodology, lingual expressions (linguistic terms) given by all experts are used as initial attribute evaluations, since they are the most natural and convenient representation of experts' evaluations. Then lingual evaluations are converted into trapezoidal fuzzy numbers, and the aggregate trapezoidal hesitant fuzzy decision matrix will be built. The case is considered when information on the attribute weights is completely unknown. The attribute weights are identified based on the De Luca and Termini information entropy concept, determined in the context of hesitant fuzzy sets. The decisions are made using the extended Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) method under a hesitant fuzzy environment. Hence, a methodology is based on a trapezoidal valued hesitant fuzzy TOPSIS decision-making model with entropy weights. The ranking of alternatives is performed by the proximity of their distances to both the fuzzy positive-ideal solution (FPIS) and the fuzzy negative-ideal solution (FNIS). For this purpose, the weighted hesitant Hamming distance is used. An example of investment decision-making is shown that clearly explains the procedure of the proposed methodology.

Keywords: In the present research, a decision support methodology for the multi-attribute group decision-making (MAGDM) problem is developed, namely for the selection of investment projects. The objective of the investment project selection problem is to choose the best project among the set of projects, seeking investment, or to rank all projects in descending order. The project selection is made considering a set of weighted attributes. To evaluate the attributes in our approach, expert assessments are used. In the proposed methodology, lingual expressions (linguistic terms) given by all experts are used as initial attribute evaluations since they are the most natural and convenient representation of experts' evaluations. Then lingual evaluations are converted into trapezoidal fuzzy numbers, and the aggregate trapezoidal hesitant fuzzy decision matrix will be built. The case is considered when information on the attribute weights is completely unknown. The attribute weights are identified based on the De Luca and Termini information entropy concept, determined in the context of hesitant fuzzy sets. The decisions are made using the extended Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) method under a hesitant fuzzy environment. Hence, a methodology is based on a trapezoidal valued hesitant fuzzy TOPSIS decision-making model with entropy weights. The ranking of alternatives is performed by the proximity of their distances to both the fuzzy positive-ideal solution (FPIS) and the fuzzy negative-ideal solution (FNIS). For this purpose, the weighted hesitant Hamming distance is used. An example of investment decision-making is shown that clearly explains the procedure of the proposed methodology.

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Authors: Elhamalsadat Ghaffari, Moghan Amirhosseinian, Amir Khaleghipour

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Multifunctional bioactive glasses (BGs) are designed with a focus on the provision of bactericidal and biological properties desired for angiogenesis, osteogenesis, and ultimately potential applications in bone tissue engineering. To achieve these, six sol-gel copper/magnesium substituted derivatives of 58S-BG, i.e. a mol% series of 60SiO₂-4P₂O₅-5CuO-(31-x) CaO/xMgO (where x=0, 1, 3, 5, 8, and 10), were synthesized. Afterwards, the effect of MgO/CaO substitution on the in vitro formation of nano-hydroxyapatite (HA), osteoblast-like cell responses and BGs antibacterial performance were studied. During the BGs synthesis, the elimination of nitrates was achieved at 700 °C that prevented the BGs crystallization and stabilized the obtained dried gels. The structural and morphological evaluations were performed with X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). These characterizations revealed that Cu-substituted 58S-BG consisting of 5 mol% MgO (BG-5/5) slightly had retarded the formation of HA. In addition, Cu-substituted 58S-BGs consisting 8 mol% and 10 mol% MgO (BG-5/8 and BG-5/10) displayed lower bioactivity probably due to the lower ion release rate of Ca–Si into the simulated body fluid (SBF). The determination of 3-(4, 5 dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and alkaline phosphate (ALP) activities proved that the highest values of both differentiation and proliferation of MC3T3-E1 cells can be obtained from a 5 mol% MgO substituted BG, while the over addition of MgO (8 mol% and 10 mol%) decreased the bioactivity. Furthermore, these novel Cu/Mg-substituted 58S-BGs displayed antibacterial effect against methicillin-resistant Staphylococcus aureus bacteria. Taken together, the results suggest the equally-substituted BG-5/5 (i.e. the one consists of 5 mol% of both CuO and MgO) as a promising candidate for bone tissue engineering, among all newly designed BGs in this work, owing to its desirable cell proliferation, ALP activity and antibacterial properties.

Keywords: apatite, bioactivity, biomedical applications, sol-gel processes

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Authors: Sandra Mitrovic, Gaurav Singh

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In many industries, including telecommunications, churn prediction has been a topic of active research. A lot of attention has been drawn on devising the most informative features, and this area of research has gained even more focus with spread of (social) network analytics. The call detail records (CDRs) have been used to construct customer networks and extract potentially useful features. However, to the best of our knowledge, no studies including network features have yet proposed a generic way of representing network information. Instead, ad-hoc and dataset dependent solutions have been suggested. In this work, we build upon a recently presented method (node2vec) to obtain representations for nodes in observed network. The proposed approach is generic and applicable to any network and domain. Unlike node2vec, which assumes a static network, we consider a dynamic and time-evolving network. To account for this, we propose an approach that constructs the feature representation of each node by generating its node2vec representations at different timestamps, concatenating them and finally compressing using an auto-encoder-like method in order to retain reasonably long and informative feature vectors. We test the proposed method on churn prediction task in telco domain. To predict churners at timestamp ts+1, we construct training and testing datasets consisting of feature vectors from time intervals [t1, ts-1] and [t2, ts] respectively, and use traditional supervised classification models like SVM and Logistic Regression. Observed results show the effectiveness of proposed approach as compared to ad-hoc feature selection based approaches and static node2vec.

Keywords: churn prediction, dynamic networks, node2vec, auto-encoders

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Authors: M. A. Zaki Ewiss, S. Afifi

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Nahda University (NUB) believes that internationalisation of higher educational is able to provide global society with an education that meets current needs and that can respond efficiently to contemporary demands and challenges, which are characterized by globalisation, interdependence, and multiculturalism. In this paper, we will discuss the the challenges of the Egyptian Higher Education system and the future vision to improve this system> In this report, the following issues will be considered: Increasing knowledge on the development of specialized programs of study at the university. Developing international cooperation programs, which focus on the development of the students and staff skills, and providing academic culture and learning opportunities. Increasing the opportunities for student mobility, and research projects for faculty members. Increased opportunities for staff, faculty and students to continue to learn foreign universities, and to benefit from scholarships in various disciplines. Taking the advantage of the educational experience and modern teaching methods; Providing the opportunities to study abroad without increasing the period of time required for graduation, and through greater integration in the curricula and programs; More cultural interaction through student exchanges.Improving and providing job opportunities for graduates through participation in the global labor market. This document sets out NUB strategy to move towards that vision. We are confident that greater explicit differentiation, greater freedom and greater collaboration are the keys to delivering the further improvement in quality we shall need to retain and strengthen our position as one of the world’s leading higher education systems.

Keywords: technology transfer higher education, knowledge transfer, internationalisation, mobility

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Authors: Lauren B. Birney

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The project utilizes the Billion Oyster Project (BOP-CCERS) place-based “restoration through education” model to promote computational thinking in NYC high school teachers and their students. Key learning standards such as Next Generation Science Standards and the NYC CS4All Equity and Excellence initiative are used to develop a computer science curriculum that connects students to their Harbor through hands-on activities based on BOP field science and educational programming. Project curriculum development is grounded in BOP-CCERS restoration science activities and data collection, which are enacted by students and educators at two Restoration Science STEM Hubs or conveyed through virtual materials. New York City Public School teachers with relevant experience are recruited as consultants to provide curriculum assessment and design feedback. The completed curriculum units are then conveyed to NYC high school teachers through professional learning events held at the Pace University campus and led by BOP educators. In addition, Pace University educators execute the Summer STEM Institute, an intensive two-week computational thinking camp centered on applying data analysis tools and methods to BOP-CCERS data. Both qualitative and quantitative analyses were performed throughout the five-year study. STEM+C – Community Based Restoration STEM Hubs. STEM Hubs are active scientific restoration sites capable of hosting school and community groups of all grade levels and professional scientists and researchers conducting long-term restoration ecology research. The STEM Hubs program has grown to include 14 STEM Hubs across all five boroughs of New York City and focuses on bringing in-field monitoring experience as well as coastal classroom experience to students. Restoration Science STEM Hubs activities resulted in: the recruitment of 11 public schools, 6 community groups, 12 teachers, and over 120 students receiving exposure to BOP activities. Field science protocols were designed exclusively around the use of the Oyster Restoration Station (ORS), a small-scale in situ experimental platforms which are suspended from a dock or pier. The ORS is intended to be used and “owned” by an individual school, teacher, class, or group of students, whereas the STEM Hub is explicitly designed as a collaborative space for large-scale community-driven restoration work and in-situ experiments. The ORS is also an essential tool in gathering Harbor data from disparate locations and instilling ownership of the research process amongst students. As such, it will continue to be used in that way. New and previously participating students will continue to deploy and monitor their own ORS, uploading data to the digital platform and conducting analysis of their own harbor-wide datasets. Programming the STEM Hub will necessitate establishing working relationships between schools and local research institutions. NYHF will provide introductions and the facilitation of initial workshops in school classrooms. However, once a particular STEM Hub has been established as a space for collaboration, each partner group, school, university, or CBO will schedule its own events at the site using the digital platform’s scheduling and registration tool. Monitoring of research collaborations will be accomplished through the platform’s research publication tool and has thus far provided valuable information on the projects’ trajectory, strategic plan, and pathway.

Keywords: environmental science, citizen science, STEM, technology

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Authors: Berger Aida

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Social entrepreneurship has emerged as an active area of practice and research within the last three decades and has called for a focus on Social Entrepreneurship innovation. Areas such as academics, practitioners , institutions or governments have placed Social Entrepreneurship on the priority list of reflexion and action. It has been accepted that Social entrepreneurship (SE) shares large similarities with its parent, Traditional Entrepreneurship (TE). SE has grown over the past ten years exploring entrepreneurial cognition and the analysis of the ways of thinking of entrepreneurs. The research community believes that value exists in grounding entrepreneurship in neuroscience and notes that SE, like Traditional Entrepreneurship, needs to undergo efforts in clarification, definition and differentiation. Moreover, gaps in SE research call for integrative multistage and multilevel framework for further research. The cognitive processes underpinning entrepreneurial action are similar for SE and TE even if Social Entrepreneurship orientation shows an increased empathy value. Theoretically, there is a need to develop sound models of how to process functions and how to work more effectively as entrepreneurs and research on efficiency improvement calls for the analysis of the most common practices in entrepreneurship. Multitasking has been recognized as a daily and unavoidable habit of entrepreneurs. Hence, we believe in the need of analyzing the multiple task phenomena as a methodology for skill acquisition. We will conduct our paper including Social Entrepreneurship within the wider spectrum of Traditional Entrepreneurship, for the purpose of simplifying the neuroscientific lecture of the entrepreneurial cognition. A question to be inquired is to know if there is a way of developing multitasking habits in order to improve entrepreneurial skills such as speed of information processing , creativity and adaptability . Nevertheless, the direct link between the neuroscientific approach to multitasking and entrepreneurship effectiveness is yet to be uncovered. That is why an extensive Literature Review on Multitasking is a propos.

Keywords: cognitive, entrepreneurial, empathy, multitasking

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Authors: Giovana Nunes Inocêncio

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The professional and technological education (EPT) plays a pivotal role in equipping students for specialized careers, and it is imperative to establish a framework for efficient data exchange among educational institutions. The primary focus of this article is to address the pressing need for document interoperability within the context of EPT. The challenges, motivations, and benefits of implementing interoperability standards for digital educational documents are thoroughly explored. These documents include EPT completion certificates, academic records, and curricula. In conjunction with the prior abstract, it is evident that the intersection of IT governance and interoperability standards holds the key to transforming the landscape of technical education in Brazil. IT governance provides the strategic framework for effective data management, aligning with educational objectives, ensuring compliance, and managing risks. By adopting interoperability standards, the technical education sector in Brazil can facilitate data exchange, enhance data security, and promote international recognition of qualifications. The utilization of the XML (Extensible Markup Language) standard further strengthens the foundation for structured data exchange, fostering efficient communication, standardization of curricula, and enhancing educational materials. The IT governance, interoperability standards, and data management critical role in driving the quality, efficiency, and security of technical education. The adoption of these standards fosters transparency, stakeholder coordination, and regulatory compliance, ultimately empowering the technical education sector to meet the dynamic demands of the 21st century.

Keywords: interoperability, education, standards, governance

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Authors: Barbara Papp

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Purpose: This article aims to rethink the relationship between the trauma and the choice of professions. By studying a homogenous sample of respondents, it seeks answers to the following question: how did personal losses that were caused by historical upheavals motivate people to enter the helping professions. By becoming helping professionals, the respondents of the survey sought to handle both historical representation and self-representation. How did psychotherapists working in the second half of the 20th century (Kádár-era in Hungary) shape their course of life? How did their family members respond to their choice of career? What forces supported or hindered them? How did they become professional helpers? Methodology: When interviewing 40 psychotherapists, the interviewer used the oral history technique. In-depth interviews were made with a focus on motivation. First, the collected material was examined using traditional content analysis tools: searching for content patterns, applying a word frequency analysis, and identifying the connections between key events and key persons. Second, a narrative psychological content analysis (NarrCat) was made. Findings: Interconnections were established between attachment, family and historical traumas and career choices. The history of the mid-20th-century period was traumatic and full of losses for the families of most of the psychotherapists concerned. Those experiences may have considerably influenced their choice of career. Working as helping therapists, they could get the opportunity to revise their losses. Conclusion: The results revealed core components that play a role in the psychotherapists’ choice of career, and also emphasized the importance of post-traumatic growth.

Keywords: biography, identity, narrative psychological content analysis, psychotherapists, trauma

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Authors: Albina Muratbekova

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One of the main tensions and challenges in the development of Sino-Indian relation is the demarcation of its frontiers. The fact that throughout the history borders had never been demarcated on ground occur a dispute between China and India after receiving sovereignty. Boundaries of India and China are divided into three sectors: Eastern, Middle and Western. The middle sector runs from India’s Uttar Pradesh to the Punjab, 545 km length of the Line of Actual Control, the lines of which was confirmed at the 9th meeting of the Expert Group held in 2001, in New Delhi. Other two sectors are still not determined and cause disputes. A western sector of the frontier is the Aksai Chin plateau, covers areas of Ladakh, Tibet, and Sinkiang. Another disputed area lies in the Eastern sector in the Himalayan region, which after 1986 became the Indian state called Arunachal Pradesh. There are two different approaches in the ways of resolving the border dispute. Chinese side keeps an opinion that the border dispute must be resolved in a timely matter unless it is favorable for China, the resolution can be left to a later generation. While India’s government due to security reasons is eager to demarcate the border. In order to study this conflict was used as a descriptive-comparative-analytical method. Also, it was done a profound analyze of conflict nature.

Keywords: border dispute, China, India, territorial claim

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Authors: Edwin Foo, Woei Wen, Lui, Meijun Zhao, Shigeru Kuchii, Chin Sai Wong, Chung Sern Goh, Yi Hao He

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This presentation presents an elderly care and assistive social robot development work. We named this robot JOS and he is restricted to table top operation. JOS is designed to have a maximum volume of 3600 cm3 with its base restricted to 250 mm and his mission is to provide companion, assist and help the elderly. In order for JOS to accomplish his mission, he will be equipped with perception, reaction and cognition capability. His appearance will be not human like but more towards cute and approachable type. JOS will also be designed to be neutral gender. However, the robot will still have eyes, eyelid and a mouth. For his eyes and eyelids, they will be built entirely with Robotis Dynamixel AX18 motor. To realize this complex task, JOS will be also be equipped with micro-phone array, vision camera and Intel i5 NUC computer and a powered by a 12 V lithium battery that will be self-charging. His face is constructed using 1 motor each for the eyelid, 2 motors for the eyeballs, 3 motors for the neck mechanism and 1 motor for the lips movement. The vision senor will be house on JOS forehead and the microphone array will be somewhere below the mouth. For the vision system, Omron latest OKAO vision sensor is used. It is a compact and versatile sensor that is only 60mm by 40mm in size and operates with only 5V supply. In addition, OKAO vision sensor is capable of identifying the user and recognizing the expression of the user. With these functions, JOS is able to track and identify the user. If he cannot recognize the user, JOS will ask the user if he would want him to remember the user. If yes, JOS will store the user information together with the capture face image into a database. This will allow JOS to recognize the user the next time the user is with JOS. In addition, JOS is also able to interpret the mood of the user through the facial expression of the user. This will allow the robot to understand the user mood and behavior and react according. Machine learning will be later incorporated to learn the behavior of the user so as to understand the mood of the user and requirement better. For the speech system, Microsoft speech and grammar engine is used for the speech recognition. In order to use the speech engine, we need to build up a speech grammar database that captures the commonly used words by the elderly. This database is built from research journals and literature on elderly speech and also interviewing elderly what do they want to robot to assist them with. Using the result from the interview and research from journal, we are able to derive a set of common words the elderly frequently used to request for the help. It is from this set that we build up our grammar database. In situation where there is more than one person near JOS, he is able to identify the person who is talking to him through an in-house developed microphone array structure. In order to make the robot more interacting, we have also included the capability for the robot to express his emotion to the user through the facial expressions by changing the position and movement of the eyelids and mouth. All robot emotions will be in response to the user mood and request. Lastly, we are expecting to complete this phase of project and test it with elderly and also delirium patient by Feb 2015.

Keywords: social robot, vision, elderly care, machine learning

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Authors: N. V. V. S. D. Prasad

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Field experiments were conducted at Regional Agricultural Research Station, Lam, Guntur, Andhra Pradesh, India for two seasons during 2011-13 to evaluate the efficacy of flupyradifurone SL 200 a new class of insecticide in butenolide group against leaf hoppers, aphids and whitefly in Cotton. The test insecticide flupyradifurone 200 was evaluated at three doses @ 150, 200 and 250 g ai/ha ha along with imidacloprid 200 SL @ 20g ai/ha, acetamiprid 20 SP @ 20g ai/ha, thiamethoxam 25 WG @ 25g ai/ha and monocrotophos 36 SL @ 360 g ai/ha as standards. Flupyradifurone SL 200 even at lower dose of 150g ai/ha exhibited superior efficacy against cotton leafhopper, Amrasca devastans than the neonicotinoids which are widely used for control of sucking pests in cotton. Against cotton aphids, Aphis gossypii. Flupyradifurone SL 200 @ 200 and 250 g ai/ha ha was proved to be effective and the lower dose @ 150g ai/ha performed better than some of the neonicotinoids. The effect of flupyradifurone SL 200 on cotton against whitefly, Bemisia tabaci was evident at higher doses of 200 and 250 g ai/ha and superior to all standard treatments, however, the lower dose is at par with neonicotinoids. The seed cotton yield of flupyradifurone 200 SL at all the doses tested was superior than imidacloprid 200 SL @ 20g ai/ha and acetamiprid 20 SP @ 20g ai/ha. There is no significant difference among the insecticidal treatments with regards to natural enemies. The results clearly suggest that flupyradifurone is a new tool to combat sucking pest problems in cotton and can well fit in IRM strategies in light of wide spread insecticide resistance in cotton sucking pests.

Keywords: cotton, flupyradifurone, neonicotinoids, sucking pests

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Authors: Kaveri Dutta, Ratna Sharma

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Indian traditional textile is a synthesis of various cultures. Art and crafts of a country showcases the rich cultural and artistic history of that nation. Prehistorically Indian handicrafts were basically made for day to day use; the yearning for aesthetic application soon saw the development of flooding designs and motifs. Similarly, Bagh print a traditional hand block Print with natural colours an Indian handicraft practiced in Bagh, Madhya Pradesh(India). Bagh print has its roots in Sindh, which is now a part of Pakistan. The present form of Bagh printing actually started in 1962 when the craftsmen migrated from Manavar to the neighboring town of Bagh situated in Madhya Pradesh and hence Bagh has always been associated with this printing style. Bagh printing basically involved blocks that are carved onto motifs that represent flora such as Jasmine, Mushroom leheriya and so on. There are some prints that were inspired by the jaali work that embellished the Taj Mahal and various other forts. Inspiration is also drawn from the landscapes and geometrical figures. The motifs evoke various moods in the serenity of the prints and that is the catchy element of Bagh prints. The development in this traditional textile is as essential as in another field. Nowadays fashion trends are fragile and innovative changes over existing fashion field in the short span is the demand of times. We must make efforts to preserve this cultural heritage of arts and crafts and this is done either by documenting the various ancient traditions or by making a blend of it. Since this craft is well known over the world, but the need is to document the original motif, fabric, technology and colors used in contemporary fashion. Hence keeping above points in mind this study on bagh print textiles of Madhya Pradesh work has been formulated. The information incorporated in the paper was based on secondary data taken from relevant books, journals, museum visit and articles. Besides for the demographic details and working profile of the artisans dealt with printing, an interview schedule was carried out in three regions of Madhya Pradesh. This work of art was expressed in Cotton fabric. For this study selected traditional motifs for Bang printing was used. Some of the popular traditional Bagh motifs are Jasmine, Mushroom leheriya, geometrical figures and jaali work. The Bagh printed cotton fabrics were developed into a range of men’s ethic wear in combination with embroideries from Rajasthan. Products developed were bandhgala jackets, kurtas, serwani and dupattas. From the present study, it can be observed that the embellished traditional Bang printed range of ethnic men’s wear resulted in the fresh and colourful pattern. The embroidered Bagh printed cotton fabric also created a huge change in a positive way among artisans of the three regions.

Keywords: art and craft of Madhya Pradesh, evolution of printing in India, history of Bagh printing, sources of inspiration

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Authors: Kristina Karapetyan, Flora Tkhruni, Tsovinar Balabekyan, Arevik Israyelyan, Tatyana Khachatryan

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The ability of the lactic acid bacteria (LAB) to prevent and cure a variety of diseases, their protective role against infections and colonization of pathogenic microorganisms in the digestive tract, has lead to the coining of the term probiotics or pro-life. LAB inhibiting the growth of pathogenic and food spoilage microorganisms, maintaining the nutritive quality and improving the shelf life of foods. They have also been used as flavor and texture producers. Enterococcus strains have been used for treatment of diseases such as diarrhea or antibiotic associated diarrhea, inflammatory pathologies that affect colon such as irritable bowel syndrome, or immune regulation, diarrhea caused by antibiotic treatments. The obtaining and investigation of biological properties of proteinoceous antibiotics, on the basis of probiotic LAB shown, that bacteriocins, metabiotics, and peptides of LAB represent bactericides have a broad range of activity and are excellent candidates for development of new prophylactic and therapeutic substances to complement or replace conventional antibiotics. The genotyping by 16S rRNA sequencing for LAB were used. Cell free culture broth (CFC) broth was purified by the Gel filtration method on the Sephadex Superfine G 25 resin. Antimicrobial activity was determined by spot-on-lawn method and expressed in arbitrary units (AU/ml). The diversity of multidrug-resistance (MDR) of pathogenic strains to antibiotics, most widely used for treatment of human diseases in the Republics of Armenia and Nagorno Karabakh were examined. It was shown, that difference of resistance of pathogens to antibiotics depends on their isolation sources. The influences of partially purified antimicrobial preparations (AMP), obtained from the different strains of Enterococcus genus on the growth of MDR pathogenic bacteria were investigated. It was shown, that bacteriocin containing partially purified preparations, obtained from different strains of Enterococcus faecium and durans species, possess bactericidal or bacteriostatic activity against antibiotic resistant intestinal, spoilage and food-borne pathogens such as Listeria monocytogenes, Staphylococcus aureus, E. coli, and Salmonella. Endemic strains of LAB, isolated from Matsoni made from donkey, buffalo and goat milk, shown broad spectrum of activity against food spoiling microorganisms, moulds and fungi, such as Salmonella sp., Esherichia coli, Aspergillus and Penicillium species. Highest activity against MDR pathogens shown bacteria, isolated from goat milk products. High stability of the investigated strains of the genus Enerococcus, isolated from samples of matsun from different regions of Nagorno-Karabakh (NKR) to the antibiotics was shown. The obtained data show high stability of the investigated different strains of the genus Enerococcus. The high genetic diversity in Enterococcus group suggests adaptations for specific mutations in different environments. Thus, endemic strains of LAB are able to produce bacteriocins with high and different inhibitory activity against broad spectrum of microorganisms isolated from different sources and belong to different taxonomic group. Prospect of the use of certain antimicrobial preparations against pathogenic strains is obvious. These AMP can be applied for long term use against different etiology antibiotic resistant pathogens for prevention or treatment of infectional diseases as an alternative to antibiotics.

Keywords: antimicrobial biopreparation, endemic lactic acid bacteria, intra-species diversity, multidrug resistance of pathogens

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Authors: Wonil Nam, Xiang Ren, Inyoung Kim, Masoud Agah, Wei Zhou

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Despite its ultrasensitive detection capability, surface-enhanced Raman spectroscopy (SERS) faces challenges as a quantitative biochemical analysis tool due to the significant dependence of local field intensity in hotspots on nanoscale geometric variations of plasmonic nanostructures. Therefore, despite enormous progress in plasmonic nanoengineering of high-performance SERS devices, it is still challenging to quantitatively correlate the measured SERS signals with the actual molecule concentrations at hotspots. A significant effort has been devoted to developing SERS calibration methods by introducing internal standards. It has been achieved by placing Raman tags at plasmonic hotspots. Raman tags undergo similar SERS enhancement at the same hotspots, and ratiometric SERS signals for analytes of interest can be generated with reduced dependence on geometrical variations. However, using Raman tags still faces challenges for real-world applications, including spatial competition between the analyte and tags in hotspots, spectral interference, laser-induced degradation/desorption due to plasmon-enhanced photochemical/photothermal effects. We show that electronic Raman scattering (ERS) signals from metallic nanostructures at hotspots can serve as the internal calibration standard to enable quantitative SERS analysis and improve biostatistical analysis. We perform SERS with Au-SiO₂ multilayered metal-insulator-metal nano laminated plasmonic nanostructures. Since the ERS signal is proportional to the volume density of electron-hole occupation in hotspots, the ERS signals exponentially increase when the wavenumber is approaching the zero value. By a long-pass filter, generally used in backscattered SERS configurations, to chop the ERS background continuum, we can observe an ERS pseudo-peak, IERS. Both ERS and SERS processes experience the |E|⁴ local enhancements during the excitation and inelastic scattering transitions. We calibrated IMRS of 10 μM Rhodamine 6G in solution by IERS. The results show that ERS calibration generates a new analytical value, ISERS/IERS, insensitive to variations from different hotspots and thus can quantitatively reflect the molecular concentration information. Given the calibration capability of ERS signals, we performed label-free SERS analysis of living biological systems using four different breast normal and cancer cell lines cultured on nano-laminated SERS devices. 2D Raman mapping over 100 μm × 100 μm, containing several cells, was conducted. The SERS spectra were subsequently analyzed by multivariate analysis using partial least square discriminant analysis. Remarkably, after ERS calibration, MCF-10A and MCF-7 cells are further separated while the two triple-negative breast cancer cells (MDA-MB-231 and HCC-1806) are more overlapped, in good agreement with the well-known cancer categorization regarding the degree of malignancy. To assess the strength of ERS calibration, we further carried out a drug efficacy study using MDA-MB-231 and different concentrations of anti-cancer drug paclitaxel (PTX). After ERS calibration, we can more clearly segregate the control/low-dosage groups (0 and 1.5 nM), the middle-dosage group (5 nM), and the group treated with half-maximal inhibitory concentration (IC50, 15 nM). Therefore, we envision that ERS calibrated SERS can find crucial opportunities in label-free molecular profiling of complicated biological systems.

Keywords: cancer cell drug efficacy, plasmonics, surface-enhanced Raman spectroscopy (SERS), SERS calibration

Procedia PDF Downloads 125