Search results for: left atrial appendage occlusion

Authors: Berina Pilipović, Saša Pilipović, Maja Pašić-Kulenović

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Inflammation is the body's response to impaired homeostasis caused by infection, injury or trauma resulting in systemic and local effects. Inflammation causes the body's response to injury and is characterized by a series of events including inflammatory response, response to pain receptors and the recovery process. Inflammation can be acute and chronic. The inflammatory response is described in three different phases. Free radical is an atom or molecule that has the unpaired electron and is therefore generally very reactive chemical species. Biologically important example of reaction with free radicals is called Lipid peroxidation (LP). Lipid peroxidation reactions occur in biological membranes, and if at the outset is not stopped with the action of antioxidants, it will bring damage to the membrane, which results in partial or complete loss of their physiological functions. Calcium antagonists and beta-adrenergic receptor antagonists are known drugs, and for many years and widely used in the treatment of cardiovascular diseases. Some of these compounds also show antioxidant activity. The mechanism of antioxidant activities of calcium antagonists and beta-blockers is unknown, since their structure varies widely. This research investigated the possible local anti-inflammatory activity of ointments containing 1% carvedilol in the white petrolatum USP. Ear inflammation was induced by 3% croton oil acetone solution, in quantity of 10 µl on both mouse ears. Albino Swiss mouse (n = 8) are treated with 2.5 mg/ear ointment, and control group was treated on the same way as previous with hydrocortisone 1% ointment (2.5 mg/ear). The other ear of the same animal was used as control one. Ointments were administered once per day, on the left ear. After treatment, ears were observed for three days. After three days, we measured mass (mg) of 6 mm ear punch of treated and controlled ears. The results of testing anti-inflammatory effects of ointments with carvedilol in the mouse ear model show stronger observed effect than ointment with 1% hydrocortisone in the same basis. Identical results were confirmed by the difference between the mass of 6 mm ears punch. The results were also confirmed by histological examination. Ointments with carvedilol showed significant reduction of the inflammation process caused by croton oil on the mouse inflammation model.

Keywords: antioxidant, carvedilol, inflammation, mouse ear

Procedia PDF Downloads 234

Authors: Robin Turner

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In the context of the strengthening conservative movements such as “Brexit” and the election of US President Donald Trump, the global political stage was shaken up by the election of Emmanuel Macron to the French presidency, defeating the far-right candidate Marine Le Pen. The election itself was a first for the Fifth Republic in which neither final candidate was from the traditional two major political parties: the left Parti Socialiste (PS) and the right Les Républicains (LR). Macron, who served as the Minister of Finance under his predecessor, founded the centrist liberal political party En Marche! in April 2016 before resigning from his post in August to launch his bid for the presidency. Between the time of the party’s creation to the first round of elections a year later, Emmanuel Macron and En Marche! had garnered enough support to make it to the run-off election, finishing far ahead of many seasoned national political figures. Now months into his presidency, the youngest President of the Republic shows no sign of losing fuel anytime soon. His unprecedented success raises a lot of questions with respect to international relations, economics, and the evolving relationship between the French government and its citizens. The effectiveness of Macron’s campaign, of course, relies on many factors, one of which is his manner of communicating his platform to French voters. Using data from oral discourse and primary material from Macron and En Marche! in sources such as party publications and Twitter, the study categorizes linguistic instruments – address, lexicon, tone, register, and syntax – to identify prevailing patterns of speech and communication. The linguistic analysis in this project is two-fold. In addition to these findings’ stand-alone value, these discourse patterns are contextualized by comparable discourse of other 2017 presidential candidates with high emphasis on that of Marine Le Pen. Secondly, to provide an alternative approach, the study contextualizes Macron’s discourse using those of two immediate predecessors representing the traditional stronghold political parties, François Hollande (PS) and Nicolas Sarkozy (LR). These comparative methods produce an analysis that gives insight to not only a contributing factor to Macron’s successful 2017 campaign but also provides insight into how Macron’s platform presents itself differently to previous presidential platforms. Furthermore, this study extends analysis to supply data that contributes to a wider analysis of the defeat of “traditional” French political parties by the “start-up” movement En Marche!.

Keywords: Emmanuel Macron, French, discourse analysis, political discourse

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Authors: Mehdi Heydari Sanglaji

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The dramatic events of the 11 September, and their tragic repercussions, catapulted issues of the political violence in and from the ‘Muslim world’ onto the political discourse, be it in patriotic speeches of campaigning politicians or the TV and news punditry. Depending on what end of the political spectrum the politician/pundit pledges fealty to, the overall analyses of political violence in the West Asia and North Africa (WANA) tends towards two overarching categories: on the Right, the diagnosis has unanimously been, ‘they must hate our freedom.’ On the Left, however, there is the contention that the West has to be counted as the primary cause of such rage, for the years of plundering of lives and resources, through colonialism, the Cold War, coups, etc. All these analyses are premised on at least two presuppositions: the violence in and from the WANA region a) is always reactionary, in the sense that it happens only in response to something the West is or does; and b) must always already be condemned, as it is essentially immoral and wrong. It is the aim of this paper to challenge such viewpoints. Through a rigorous study of the historical discourses on political violence in the Leftist organizations active in Algeria and Lebanon, we claim there is a myriad of diverse reasons and justifications presented for advocating political violence in these countries that defy facile categorization. Inspecting such rhetoric for inciting political violence in Leftist discourses, and how some of these reasonings have percolated into other movements in the region (e.g., Islamist ones), will reveal a wealth of indigenous discourses on the subject that has been largely neglected by the Western Media punditry and even by the academia. The indigenous discourses on political violence, much of which overlaps with emancipatory projects in the region, partly follow grammar and logic, which may be different from those developed in the West, even by its more critical theories. Understanding so different epistemology of violence, and the diverse contexts in which political violence might be justifiable in the mind of ‘the other,’ necessitates a historical, materialist, and genealogical study of the discourse already in practice in the WANA region. In that regard, both critical terrorism studies and critical discourse analysis provide exemplary tools of analysis. Capitalizing on such tools, this project will focus on unearthing a history of thought that renders moot the reduction of all instances of violence in the region to an Islamic culture or imperialism/colonialism. The main argument in our research is that by studying the indigenous discourses on political violence, we will be far more equipped in understanding the reasons and the possible solutions for acts of terrorism in and from the region.

Keywords: political violence, terrorism, leftist organizations, West Asia/North Africa

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Authors: Ujunma Nnenna Egbuawa

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Rape or sexual assault is a hideous crime of violence done predominantly to women and occasionally to men. In institutions of higher learning, it’s mostly experienced within or outside the campus environment due to students who are from different backgrounds socially. These students also have been imbibed with conflicting ethical standards, thus act both morally and amoral with respect to their sexual urges. The most affected among these are the female students who live outside the campus environment that is suitable for any immoral activity. These female students that are victims of rape hardly would want to be identified and this has left them as habitual prey to the unsuspecting predators. The socio-cultural setting has also been a contributory factor to the psychological and physical damage these victims face throughout their time of study as female rape victims. This is an empirical study designed to elicit information from students of Federal Polytechnic Nekede Owerri Imo State Nigeria on whether they have been sexually assaulted or raped and how they handled it thereafter. This institution was used as a case study because the provost of this tertiary institution is a woman whose name is Dr( Mrs ) C.U Njoku who has made consented efforts to ensure these rape victims rise above the social stigma associated with it. This rector has also put in some measures to bring about a decline in cases of rape within and outside the campus environment. She also granted the researcher an oral interview on how she has been able to achieve these and the challenges she hitherto faced in the process. Three research questions and a hypothesis guided the study. Samples of 119 students were used and stratification was done for sex, age and the academic level of the students. 14 item questionnaires were used and data generated from the survey were analyzed using percentages. This workshop would engage the participants by investigating some courses that may help in declining the rate of rape cases within a campus. Also, necessary measures that would be taken to help in sensitizing the tertiary institutions in areas that can aid the healing procedures of these victims. The need also for guidance and counseling unit is also a necessity for the psychological survival of these rape victims. As a result, the participants would gain an increased awareness of the influence of rape and sexual assault on campus. There ought to be a paradigm shift in institutions of higher learning in policies, administrative decisions and introduction of courses that will uplift ethical standards in order to bring about a change both locally and globally.

Keywords: institutions, psychological, sexual assault, socio-cultural

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Authors: Mauricio E. Cruz, Ilse Cervantes, Manuel J. Fabela

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The evaluation of the maneuverability of road vehicles is generally carried out through the use of specialized computer programs due to the advantages they offer compared to the experimental method. These programs are based on purely geometric considerations of the characteristics of the vehicles, such as main dimensions, the location of the axles, and points of articulation, without considering parameters such as weight distribution and magnitude, tire properties, etc. In this paper, we address the problem of maneuverability in a semi-trailer truck to navigate urban streets, maneuvering yards, and parking lots, using the Ackerman principle to propose a kinematic model that, through geometric considerations, it is possible to determine the space necessary to maneuver safely. The model was experimentally validated by conducting maneuverability tests with an articulated vehicle. The measurements were made through a GPS that allows us to know the position, trajectory, and speed of the vehicle, an inertial motion unit (IMU) that allows measuring the accelerations and angular speeds in the semi-trailer, and an instrumented steering wheel that allows measuring the angle of rotation of the flywheel, the angular velocity and the torque applied to the flywheel. To obtain the steering angle of the tires, a parameterization of the complete travel of the steering wheel and its equivalent in the tires was carried out. For the tests, 3 different angles were selected, and 3 turns were made for each angle in both directions of rotation (left and right turn). The results showed that the proposed kinematic model achieved 95% accuracy for speeds below 5 km / h. The experiments revealed that that tighter maneuvers increased significantly the space required and that the vehicle maneuverability was limited by the size of the semi-trailer. The maneuverability was also tested as a function of the vehicle load and 3 different load levels we used: light, medium, and heavy. It was found that the internal turning radii also increased with the load, probably due to the changes in the tires' adhesion to the pavement since heavier loads had larger contact wheel-road surfaces. The load was found as an important factor affecting the precision of the model (up to 30%), and therefore I should be considered. The model obtained is expected to be used to improve maneuverability through a robust control system.

Keywords: articuled vehicle, experimental validation, kinematic model, maneuverability, semi-trailer truck

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Authors: N. Azouaou, H. Mokaddem, D. Senadjki, K. Kedjit, Z. Sadaoui

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Introduction: Water contamination caused by dye industries, including food, leather, textile, plastic, cosmetics, paper-making, printing and dye synthesis, has caused more and more attention, since most dyes are harmful to human being and environments. Untreated coffee grounds were used as a high-efficiency adsorbent for the removal of a cationic dye (methylene blue, MB) from aqueous solution. Characterization of the adsorbent was performed using several techniques such as SEM, surface area (BET), FTIR and pH zero charge. The effects of contact time, adsorbent dose, initial solution pH and initial concentration were systematically investigated. Results showed the adsorption kinetics followed the pseudo-second-order kinetic model. Langmuir isotherm model is in good agreement with the experimental data as compared to Freundlich and D–R models. The maximum adsorption capacity was found equal to 52.63mg/g. In addition, the possible adsorption mechanism was also proposed based on the experimental results. Experimental: The adsorption experiments were carried out in batch at room temperature. A given mass of adsorbent was added to methylene blue (MB) solution and the entirety was agitated during a certain time. The samples were carried out at quite time intervals. The concentrations of MB left in supernatant solutions after different time intervals were determined using a UV–vis spectrophotometer. The amount of MB adsorbed per unit mass of coffee grounds (qt) and the dye removal efficiency (R %) were evaluated. Results and Discussion: Some chemical and physical characteristics of coffee grounds are presented and the morphological analysis of the adsorbent was also studied. Conclusions: The good capacity of untreated coffee grounds to remove MB from aqueous solution was demonstrated in this study, highlighting its potential for effluent treatment processes. The kinetic experiments show that the adsorption is rapid and maximum adsorption capacities qmax= 52.63mg/g achieved in 30min. The adsorption process is a function of the adsorbent concentration, pH and metal ion concentration. The optimal parameters found are adsorbent dose m=5g, pH=5 and ambient temperature. FTIR spectra showed that the principal functional sites taking part in the sorption process included carboxyl and hydroxyl groups.

Keywords: adsorption, methylene blue, coffee grounds, kinetic study

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Authors: Branimir Jurun, Elza Jurun

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The focus of this paper is the description of an instrument called 'Quattuor 45' and defining of wave pressure measurement. Special attention is given to measurement of wave pressure created by the wind speed increasing obtained with the instrument 'Quattuor 45' in the investigated area. The study begins with respect to theoretical attitudes and numerous up to date investigations related to the waves approaching the coast. The detailed schematic view of the instrument is enriched with pictures from ground plan and side view. Horizontal stability of the instrument is achieved by mooring which relies on two concrete blocks. Vertical wave peak monitoring is ensured by one float above the instrument. The synthesis of horizontal stability and vertical wave peak monitoring allows to create a representative database for wave pressure measuring. Instrument ‘Quattuor 45' is named according to the way the database is received. Namely, the electronic part of the instrument consists of the main chip ‘Arduino', its memory, four load cells with the appropriate modules and the wind speed sensor 'Anemometers'. The 'Arduino' chip is programmed to store two data from each load cell and two data from the anemometer on SD card each second. The next part of the research is dedicated to data processing. All measured results are stored automatically in the database and after that detailed processing is carried out in the MS Excel. The result of the wave pressure measurement is synthesized by the unit of measurement kN/m². This paper also suggests a graphical presentation of the results by multi-line graph. The wave pressure is presented on the left vertical axis, while the wind speed is shown on the right vertical axis. The time of measurement is displayed on the horizontal axis. The paper proposes an algorithm for wind speed measurements showing the results for two characteristic winds in the Adriatic Sea, called 'Bura' and 'Jugo'. The first of them is the northern wind that reaches high speeds, causing low and extremely steep waves, where the pressure of the wave is relatively weak. On the other hand, the southern wind 'Jugo' has a lower speed than the northern wind, but due to its constant duration and constant speed maintenance, it causes extremely long and high waves that cause extremely high wave pressure.

Keywords: instrument, measuring unit, waves pressure metering, wind seed measurement

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Authors: Lauren Schuldt Wilson

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Felicia Hemans’ memorializing of the unwritten lives of women and the consequent allowance for marginalized voices to remember and be remembered has been considered by many critics in terms of ekphrasis and elegy, terms which privilege the question of whether Hemans’ poeticizing can represent lost voices of history or only her poetic expression. Amy Gates, Brian Elliott, and others point out Hemans’ acknowledgement of the self-projection necessary for imaginatively filling the absences of unrecorded histories. Yet, few have examined the complex temporal positioning Hemans inscribes in these moments of self-projection and imaginative historicizing. In poems like ‘The Image in Lava,’ Hemans maps not only a lost past, but also a lost potential future onto the image of a dead infant in its mother’s arms, the discovery and consideration of which moves the imagined viewer to recover and incorporate the ‘hope’ encapsulated in the figure of the infant into a reevaluation of national time embodied by the ‘relics / Left by the pomps of old.’ By examining Hemans’ acknowledgement and response to Percy Bysshe Shelley’s ‘Ozymandias,’ this essay explores how Hemans’ depictions of imaginative historicizing open new horizons of possibility and reevaluate temporal value structures by imagining previously undiscovered or unexplored potentialities of the past. Where Shelley’s poem mocks the futility of national power and time, this essay outlines Hemans’ suggestion of alternative threads of identity and temporal meaning-making which, regardless of historical veracity, exist outside of and against the structures Shelley challenges. Counter to previous readings of Hemans’ poem as celebration of either recovered or poetically constructed maternal love, this essay argues that Hemans offers a meditation on sites of reproduction—both of personal reproductive futurity and of national reproduction of power. This meditation culminates in Hemans’ gesturing towards a method of historicism by which the imagined viewer reinvigorates the sterile, ‘shattered visage’ of national time by forming temporal identity through the imagining of trans-historical hope inscribed on the infant body of the universal, individual subject rather than the broken monument of the king.

Keywords: futurity, national temporalities, reproduction, revisionary histories

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Authors: Ibrahim Siddig Hamid, Ikram Mohamed Eltayeb

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Trachyspermum ammi belongs to the family Apiaceae, is used traditionally for the treatment of gastrointestinal ailments, lack of appetite and bronchial problems as well used as antiseptic, antimicrobial, antipyretic, febrifugal and in the treatment of typhoid fever. Peganum harmala belongs to the family Zygophyllaceae it has been reported to have an antibacterial activity and used to treat depression and recurring fevers. It also used to kill algae, bacteria, intestinal parasites and molds. In Sudan, the combination of two plants are traditionally used for the treatment of bacillary dysentery. Bacillary dysentery is caused by one or more types of Shigella species bacteria mainly Shigella dysenteri and shigella flexneri. Bacillary dysentery is mainly found in hot countries like Sudan with poor hygiene and sanitation. Bacillary dysentery causes sudden onset of high fever and chills, abdominal pain, cramps and bloating, urgency to pass stool, weight loss, and dehydration and if left untreated it can lead to serious complications including delirium, convulsions and coma. A serious infection like this can be fatal within 24 hours. The objective of this study is to investigate the in vitro susceptibility of Sh. flexneri and Sh. dysenteriae to the T. ammi and P. harmala. T. ammi and P. harmala were extracted by 96% ethanol using Soxhlet apparatus. The antimicrobial activity of the extracts was investigated according to the disc diffusion method. The discs were prepared by soaking sterilized filter paper discs in 20 microliter of serially diluted solutions of each plant extract with the concentrations (100, 50, 25, 12.5, 6.25mg/dl) then placing them on Muller Hinton Agar plates that were inoculated with bacterial suspension separately, the plates were incubated for 24 hours at 37c and the minimum inhibitory concentration of the extract which was the least concentration of the extract to inhibit fungal growth was determined. The results showed the high antimicrobial activity of T. ammi extract with an average diameter zone ranging from 18-20 mm and its minimum inhibitory concentration was found to be 25 mg/ml against the two shigella species. P. harmala extract was found to have slight antibacterial effect against the two bacteria. This result justified the Sudanese traditional use of Trachyspermum ammi plant for the treatment of bacillary dysentery.

Keywords: harmala, peganum, shigella, trachyspermum

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Authors: Amrit Vasdev, Edwin Rho, Gurinder Vasdev

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Robotic surgery has enabled a new spectrum of minimally invasive breast reconstruction by improving visualization, surgeon posturing, and improved patient outcomes.1 The DaVinci robot system can be utilized in nipple sparing mastectomies and reconstructions. The process involves the insufflation of the subglandular space and a dissection of the mammary gland with a combination of cautery and blunt dissection. This case outlines a 35-year-old woman who has a long-standing family history of breast cancer and a diagnosis of a deleterious BRCA2 genetic mutation. She has decided to proceed with bilateral nipple sparing mastectomies with implants. Her perioperative mammogram and MRI were negative for masses, however, her left internal mammary lymph node was enlarged. She has taken oral contraceptive pills for 3-5 years and denies DES exposure, radiation therapy, human replacement therapy, or prior breast surgery. She does not smoke and rarely consumes alcohol. During the procedure, the patient received a standardized anesthetic for out-patient surgery of propofol infusion, succinylcholine, sevoflurane, and fentanyl. Aprepitant was given as an antiemetic and preoperative Tylenol and gabapentin for pain management. Concerns for the patient during the procedure included CO2 insufflation into the subcutaneous space. With CO2 insufflation, there is a potential for rapid uptake leading to severe acidosis, embolism, and subcutaneous emphysema.2To mitigate this, it is important to hyperventilate the patient and reduce both the insufflation pressure and the CO2 flow rate to the minimal acceptable by the surgeon. For intraoperative monitoring during this 6-9 hour long procedure, it has been suggested to utilize an Arterial-Line for end-tidal CO2 monitoring. However, in this case, it was not necessary as the patient had excellent cardiovascular reserve, and end-tidal CO2 was within normal limits for the duration of the procedure. A BIS monitor was also utilized to reduce anesthesia burden and to facilitate a prompt discharge from the PACU. Minimal Invasive Robotic Surgery will continue to evolve, and anesthesiologists need to be prepared for the new challenges ahead. Based on our limit number of patients, robotic mastectomy appears to be a safe alternative to open surgery with the promise of clearer tissue demarcation and better cosmetic results.

Keywords: anesthesia, mastectomies, robotic, hypercarbia

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Authors: Isalira Peroba Ramos, Cherley Borba Vieira de Andrade, Grazielle Suhett, Camila Salata, Paulo Cesar Canary, Guilherme Visconde Brasil, Antonio Carlos Campos de Carvalho, Regina Coeli dos Santos Goldenberg

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Background: The therapeutic options for patients with cancer now include increasingly complex combinations of medications, radiation therapy (RT), and surgical intervention. Many of these treatments have important potential adverse cardiac effects and are likely to have significant effects on patient outcomes. Cell therapy appears to be promising for the treatment of chronic and degenerative diseases, including cardiomyopathy induced by RT, as the current therapeutic options are insufficient. Aims: To evaluate the potential of bone marrow mesenchymal cells (BMMCs) in radioinduced cardiac damage Methods: Female Wistar rats, 3 months old (Ethics Committee 054/14), were divided into 2 groups, non-treated irradiated group (IR n=15) and irradiated and BMMC treated (IRT n=10). Echocardiography was performed to evaluate heart function. After euthanasia, 3 months post treatment; the left ventricle was removed and prepared for RT-qPCR (VEGF and Pro Collagen I) and histological (picrosirius) analysis. Results: In both groups, 45 days after irradiation, ejection fraction (EF) was in the normal range for these animals (> 70%). However, the BMMC treated group had EF (83.1%±2.6) while the non-treated IR group showed a significant reduction (76.1%±2.6) in relation to the treated group. In addition, we observed an increase in VEGF gene expression and a decrease in Pro Collagen I in IRT when compared to IR group. We also observed by histology that the collagen deposition was reduced in IRT (10.26%±0.83) when compared to IR group (25.29%±0.96). Conclusions: Treatment with BMMCs was able to prevent ejection fraction reduction and collagen deposition in irradiated animals. The increase of VEGF and the decrease of pro collagen I gene expression might explain, at least in part, the cell therapy benefits. All authors disclose no financial or personal relationships with individuals or organizations that could be perceived to bias their work. Sources of funding: FAPERJ, CAPES, CNPq, MCT.

Keywords: mesenchymal cells, radioation, cardiotoxicity, bone marrow

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Authors: Qian Wang, Haibo Gu

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To drive practical interpretations and applications of various policies in building the transnational education joint-ventures, middle managers learn to navigate through uncertainties and ambiguities. However, the current literature views very little about those middle managers’ experiences, perceptions, and practices. This paper takes the empirical approach and aims to uncover the middle managers’ experiences by conducting interviews, campus visits, and document analysis. Following the qualitative research method approach, the researchers gathered information from a mixture of fourteen foreign and Chinese managers. Their perceptions of the China-foreign cooperation in higher education and their perceived roles have offered important, valuable insights to this group of people’s attitudes and management performances. The diverse cultural and demographic backgrounds contributed to the significance of the study. There are four key findings. One, middle managers’ immediate micro-contexts and individual attitudes are the top two influential factors in managers’ performances. Two, the foreign middle managers showed a stronger sense of self-identity in risk-taking. Three, the Chinese middle managers preferred to see difficulties as part of their assigned responsibilities. Four, middle managers in independent universities demonstrated a stronger sense of belonging and fewer frustrations than middle managers in secondary institutes. The researchers propose that training for managers in a transnational educational setting should consider these discoveries when select fitting topics and content. In particular, middle managers should be better prepared to anticipate their everyday jobs in the micro-environment; hence, information concerning sponsor organizations’ working culture is as essential as knowing the national and local regulations, and socio-culture. Different case studies can help the managers to recognize and celebrate the diversity in transnational education. Situational stories can help them to become aware of the diverse and wide range of work contexts so that they will not feel to be left alone when facing challenges without relevant previous experience or training. Though this research is a case study based in the Chinese transnational higher education setting, the implications could be relevant and comparable to other transnational higher education situations and help to continue expanding the potential applications in this field.

Keywords: educational management, middle manager performance, transnational higher education

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Authors: Alana E. Jansen

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With such a large proportion of organisations relying on the use of team-based structures, it is surprising that so few teams would be classified as high-performance teams. While the impact of team composition on performance has been researched frequently, there have been conflicting findings as to the effects, particularly when examined alongside other team factors. To broaden the theoretical perspectives on this topic and potentially explain some of the inconsistencies in research findings left open by other various models of team effectiveness and high-performing teams, the present study aims to use the Job-Demands-Resources model, typically applied to burnout and engagement, as a framework to examine how team composition factors (particularly diversity in team member characteristics) can facilitate or hamper team effectiveness. This study used a virtual interview design where participants were asked to both rate and describe their experiences, in one high-performing and one low-performing team, over several factors relating to demands, resources, team composition, and team effectiveness. A semi-structured interview protocol was developed, which combined the use of the Likert style and exploratory questions. A semi-targeted sampling approach was used to invite participants ranging in age, gender, and ethnic appearance (common surface-level diversity characteristics) and those from different specialties, roles, educational and industry backgrounds (deep-level diversity characteristics). While the final stages of data analyses are still underway, thematic analysis using a grounded theory approach was conducted concurrently with data collection to identify the point of thematic saturation, resulting in 35 interviews being completed. Analyses examine differences in perceptions of demands and resources as they relate to perceived team diversity. Preliminary results suggest that high-performing and low-performing teams differ in perceptions of the type and range of both demands and resources. The current research is likely to offer contributions to both theory and practice. The preliminary findings suggest there is a range of demands and resources which vary between high and low-performing teams, factors which may play an important role in team effectiveness research going forward. Findings may assist in explaining some of the more complex interactions between factors experienced in the team environment, making further progress towards understanding the intricacies of why only some teams achieve high-performance status.

Keywords: diversity, high-performing teams, job demands and resources, team effectiveness

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Authors: Mohamed A. Saleem

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Using mostly seismic data, this study intends to show some examples of igneous intrusions found in some areas of the Sirt Basin and explore the period of their emplacement as well as the interrelationships between these sills. The study area is located in the south of the Zallah Trough, south-west Sirt basin, Libya. It is precisely between the longitudes 18.35ᵒ E and 19.35ᵒ E, and the latitudes 27.8ᵒ N and 28.0ᵒ N. Based on a variety of criteria that are usually used as marks on the igneous intrusions, twelve igneous intrusions (Sills), have been detected and analysed using 3D seismic data. One or more of the following were used as identification criteria: the high amplitude reflectors paired with abrupt reflector terminations, vertical offsets, or what is described as a dike-like connection, the violation, the saucer form, and the roughness. Because of their laying between the hosting layers, the majority of these intrusions are classified as sills. Another distinguishing feature is the intersection geometry link between some of these sills. Every single sill has given a name just to distinguish the sills from each other such as S-1, S-2, and …S-12. To avoid the repetition of description, the common characteristics and some statistics of these sills are shown in summary tables, while the specific characters that are not common and have been noticed for each sill are shown individually. The sills, S-1, S-2, and S-3, are approximately parallel to one other, with the shape of these sills being governed by the syncline structure of their host layers. The faults that dominated the strata (pre-upper Cretaceous strata) have a significant impact on the sills; they caused their discontinuity, while the upper layers have a shape of anticlines. S-1 and S-10 are the group's deepest and highest sills, respectively, with S-1 seated near the basement's top and S-10 extending into the sequence of the upper cretaceous. The dramatic escalation of sill S-4 can be seen in N-S profiles. The majority of the interpreted sills are influenced and impacted by a large number of normal faults that strike in various directions and propagate vertically from the surface to the basement's top. This indicates that the sediment sequences were existed before the sill’s intrusion, were deposited, and that the younger faults occurred more recently. The pre-upper cretaceous unit is the current geological depth for the Sills S-1, S-2 … S-9, while Sills S-10, S-11, and S-12 are hosted by the Cretaceous unit. Over the sills S-1, S-2, and S-3, which are the deepest sills, the pre-upper cretaceous surface has a slightly forced folding, these forced folding is also noticed above the right and left tips of sill S-8 and S-6, respectively, while the absence of these marks on the above sequences of layers supports the idea that the aforementioned sills were emplaced during the early upper cretaceous period.

Keywords: Sirt Basin, Zallah Trough, igneous intrusions, seismic data

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Authors: Jonathon Bailey, Neil Bressloff, Nick Curzen

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Transcatheter Aortic Valve Implantation (TAVI) devices are stent-like frames with prosthetic leaflets on the inside, which are percutaneously implanted. The device in a crimped state is fed through the arteries to the aortic root, where the device frame is opened through either self-expansion or balloon expansion, which reveals the prosthetic valve within. The frequency at which TAVI is being used to treat aortic stenosis is rapidly increasing. In time, TAVI is likely to become the favoured treatment over Surgical Valve Replacement (SVR). Mortality after TAVI has been associated with severe Paravalvular Aortic Regurgitation (PAR). PAR occurs when the frame of the TAVI device does not make an effective seal against the internal surface of the aortic root, allowing blood to flow backwards about the valve. PAR is common in patients and has been reported to some degree in as much as 76% of cases. Severe PAR (grade 3 or 4) has been reported in approximately 17% of TAVI patients resulting in post-procedural mortality increases from 6.7% to 16.5%. TAVI devices, like SVR devices, are circular in cross-section as the aortic root is often considered to be approximately circular in shape. In reality, however, the aortic root is often non-circular. The ascending aorta, aortic sino tubular junction, aortic annulus and left ventricular outflow tract have an average ellipticity ratio of 1.07, 1.09, 1.29, and 1.49 respectively. An elliptical aortic root does not severely affect SVR, as the leaflets are completely removed during the surgical procedure. However, an elliptical aortic root can inhibit the ability of the circular Balloon-Expandable (BE) TAVI devices to conform to the interior of the aortic root wall, which increases the risk of PAR. Self-Expanding (SE) TAVI devices are considered better at conforming to elliptical aortic roots, however the valve leaflets were not designed for elliptical function, furthermore the incidence of PAR is greater in SE devices than BE devices (19.8% vs. 12.2% respectively). If a patient’s aortic root is too severely elliptical, they will not be suitable for TAVI, narrowing the treatment options to SVR. It therefore follows that in order to increase the population who can undergo TAVI, and reduce the risk associated with TAVI, non-circular devices should be developed. Computational simulations were employed to further advance our understanding of non-circular TAVI devices. Radial stiffness of the TAVI devices in multiple directions, frame bending stiffness and resistance to balloon induced expansion are all computationally simulated. Finally, a simulation has been developed that demonstrates the expansion of TAVI devices into a non-circular patient specific aortic root model in order to assess the alterations in deployment dynamics, PAR and the stresses induced in the aortic root.

Keywords: tavi, tavr, fea, par, fem

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Authors: Jorge Martínez-Rodríguez, Esther Pérez-Carrillo, Diana Laura Anchondo Álvarez, Julia Lucía Leal Villarreal, Mariana Juárez Dominguez, Luisa Fernanda Torres Hernández, Daniela Salinas Morales, Erick Heredia-Olea

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Maize tortillas are a staple food in Mexico which are mostly made by nixtamalization, which includes the cooking and steeping of maize kernels in alkaline conditions. The cooking step in nixtamalization demands a lot of energy and also generates nejayote, a water pollutant, at the end of the process. The aim of this study was to reduce the cooking time by adding a maize soaking step before nixtamalization while maintaining the quality properties of masa and tortillas. Maize kernels were soaked for 36 h to increase moisture up to 36%. Then, the effect of different cooking times (0, 5, 10, 15, 20, 20, 25, 30, 35, 45-control and 50 minutes) was evaluated on viscosity profile (RVA) of masa to select the treatments with a profile similar or equal to control. All treatments were left steeping overnight and had the same milling conditions. Treatments selected were 20- and 25-min cooking times which had similar values for pasting temperature (79.23°C and 80.23°C), Maximum Viscosity (105.88 Cp and 96.25 Cp) and Final Viscosity (188.5 Cp and 174 Cp) to those of 45 min-control (77.65 °C, 110.08 Cp, and 186.70 Cp, respectively). Afterward, tortillas were produced with the chosen treatments (20 and 25 min) and for control, then were analyzed for texture, damage starch, colorimetry, thickness, and average diameter. Colorimetric analysis of tortillas only showed significant differences for yellow/blue coordinates (b* parameter) at 20 min (0.885), unlike the 25-minute treatment (1.122). Luminosity (L*) and red/green coordinates (a*) showed no significant differences from treatments with respect control (69.912 and 1.072, respectively); however, 25 minutes was closer in both parameters (73.390 and 1.122) than 20 minutes (74.08 and 0.884). For the color difference, (E), the 25 min value (3.84) was the most similar to the control. However, for tortilla thickness and diameter, the 20-minute with 1.57 mm and 13.12 cm respectively was closer to those of the control (1.69 mm and 13.86 cm) although smaller to it. On the other hand, the 25 min treatment tortilla was smaller than both 20 min and control with 1.51 mm thickness and 13.590 cm diameter. According to texture analyses, there was no difference in terms of stretchability (8.803-10.308 gf) and distance for the break (95.70-126.46 mm) among all treatments. However, for the breaking point, all treatments (317.1 gf and 276.5 gf for 25 and 20- min treatment, respectively) were significantly different from the control tortilla (392.2 gf). Results suggest that by adding a soaking step and reducing cooking time by 25 minutes, masa and tortillas obtained had similar functional and textural properties to the traditional nixtamalization process.

Keywords: tortilla, nixtamalization, corn, lime cooking, RVA, colorimetry, texture, masa rheology

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Authors: Mahin Pourmorad Naseri

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Myths have been an inseparable aspect of man’s life in all nations and cultures across the world over time; however, it seems that the form and use of myths in the poetry of the 20th century have gained a new meaning and purpose. Among the poets of the time, T. S. Eliot in English and Mahdi Akhavan Sales in Persian are the two mostly referred to in this regard. In this paper, the pattern of heroic journey as the main theme in the poetry of Akhavan and Eliot will be reviewed, compared, and contrasted. Attempts have been made to find out how the myth of the hero’s journey has been reflected in the century’s well-known poetry and if myth allusions in these poems confirm or reject Campbell’s claim that mythology can be an appropriate psychological cure for man’s loneliness in today’s life. T. S. Eliot (1888-1965), the English poet, essayist, playwright, publisher, and critic, is mostly known for his modernist poetry and the extensive allusions to mythologies and world literary masterpieces. At the same time, Mahdi Akhavan Sales (1929-1990) Iranian poet, one of the pioneers of modern Persian poetry, is also most well-known for his epic poetic style (Khorasani Style) and also his high amount of allusions to myths, especially Zoroastrian mythology, and his myth-making technique. Although their greatly different cultural background may cause the similarities in their poetic style and themes not to attract attention, at first sight, reading the poems closely through the light of the 20th century’s life context and literary movements reveal interesting similarities in the way they understand and apply myth in their poetry. The present paper reviews the theme of the hero’s journey in Akhavan’s Chavooshi and Eliot’s “Journey of the Magi” from the perspective of Campbell’s notion of mono-myth or the pattern of mythic hero’s journey. The poems will be reviewed in search of the steps of the inward journey the heroes make, the goals they pursue, and how successful they are in achieving the goals. The findings of the study reveal that while the difference in the social context of the poets makes the small differences in the stages of the journey, both journeys end in a gloomy atmosphere for the disappointedly isolated hero who is finally left alone in the godless and materialistic world of 20th century. It is also evident that both poets meant to fulfill their responsibility of reviving mythology in writing the poems.

Keywords: myth, Akhavan, Eliot, poetry, hero's journey

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Authors: Magda Gorczyca, Zofia Nocoń

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Past and current studies from different countries showed that river engineering leads to environmental degradation and extinction of many species - often those protected by local and international wildlife conservation laws. Through the years, the main focus of rivers utilization has shifted from industrial applications to recreation and wildlife preservation with a focus on keeping the biodiversity which plays a significant role in preventing climate changes. Thus an opportunity appeared to recreate flooding areas and natural habitats, which are very rare in the scale of Europe. Additionally, river restoration helps to avoid floodings and periodic droughts, which are usually very damaging to the economy. In this research, the biodiversity of dragonflies and ground beetles was analyzed in the context of plant communities and forest stands structure. Results were enriched with data from past and current literature. A comparison was made between two parts of the Odra river. A part where oxbow lake and riparian forest were separated from the river bed by embankment and a part of the river with floodplains left intact. Validity assessment of embankments relocation was made based on the research results. In the period between May and September, insects were collected, phytosociological analysis were taken, and forest stand structure properties were specified. In the part of the river not separated by the embankments, rare and protected species of plants were spotted (e.g., Trapanatans, Salvinianatans) as well as greater species and quantitive diversity of dragonfly. Ground beetles fauna, though, was richer in the area separated by the embankment. Even though the research was done during only one season and in a limited area, the results can be a starting point for further extended research and may contribute to acquiring legal wildlife protection and restoration of the researched area. During the research, the presence of invasive species Impatiens parviflora, Echinocystislobata, and Procyonlotor were observed, which may lead to loss of the natural values of the researched areas.

Keywords: carabidae, floodplains, middle Odra river, Odonata, oxbow lakes, riparian forests

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Authors: M. S. Sarkar, J. A. Johnson, S. Sen, G. K. Saha, K. Ramesh

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There is growing recognition of several important roles played by tigers for maintaining sustainable biodiversity at diverse ecosystems in South and South-East Asia. Only <3200 individuals are left in the wild because of poaching and habitat loss. Thus, restoring wild population is an emerging as well as important conservation initiative, but such efforts still remain challenging due to their elusive and solitary behavior. After careful translocation of few individuals, how reintroduced individuals colonize into suitable habitat and achieve stable stage population through reproduction is vital information for forest managers and policy makers of its 13 distribution range countries. Four wild and two captive radio collared tigers were reintroduced at Panna Tiger Reserve, Madhya-pradesh, India during 2009-2014. We critically examined their settlement behavior and population growth over the period. Results from long term telemetry data showed that male explored larger areas rapidly in short time span, while females explored small area in long time period and with significant high rate of movement in both sexes during exploratory period. Significant difference in home range sizes of tigers were observed in exploratory and settlement period. Though all reintroduced tigers preferred densely vegetated undisturbed forest patches within the core area of tiger reserve, a niche based k select analysis showed that individual variation in habitat selection was prominent among reintroduced tigers. Total 18 litter of >42 known cubs were born with low mortality rate, high maternity rate, high observed growth rate and short generation time in both the sexes. The population achieved its carrying capacity in a very short time span, marking success of this current tiger conservation programme. Our study information could provide significant insights on the tiger biology of translocated tigers with implication for future conservation strategies that consider translocation based recovery in their range countries.

Keywords: reintroduction, tiger, home range, demography

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Authors: Hala Barakat

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Architecture plays a crucial role in the colonization and organization of spaces, as well as the preservation of cultures and history. As a result of 70 years of occupation, Palestinian land, culture, and history are endangered today. The government of Israel has used architecture to strangulate Palestinians out and seize their land. The occupation has managed to fragment the West Bank and cause sensible scars on the landscape by creating obstacles, barriers, watchtowers, checkpoints, walls, apartheid roads, border devices, and illegal settlements to unjustly claim land from its indigenous population. The apartheid architecture has divided the Palestinian social and urban fabric into pieces, similarly to the Bantustans. The architectural techniques and methods used by the occupation are evidence of prejudice, and while the illegal settlements remain to be condemned by the United Nations, little is being done to officially end this apartheid. Illegal settlements range in scale from individual units to established cities and house more than 60,000 Israeli settlers that immigrated from all over Europe and the United States. Often architecture by Israel is being directed towards expressing ideologies and serving as evidence of its political agenda. More than 78% of what was granted to Palestine after the development of the Green Line in 1948 is under Israeli occupation today. This project aims to map the illegal architecture as a criticism of governmental agendas in the West Bank and Historic Palestinian land. The paper will also discuss the resistance to the newly developed plan for the last Arab village in Jerusalem, Lifta. The illegal architecture has isolated Palestinians from each other and installed obstacles to control their movement. The architecture of occupation has no ethical or humane logic but rather entirely political, administrative, and it should not be left for the silenced architecture to tell the story. Architecture is not being used as a connecting device but rather a way to implement political injustice and spatial oppression. By narrating stories of the architecture of occupation, we can highlight the spatial injustice of the complex apartheid infrastructure. The Israeli government has managed to intoxicate architecture to serve as a divider between cultural groups, allowing the unlawful and unethical architecture to define its culture and values. As architects and designers, the roles we play in the development of illegal settlements must align with the spatial ethics we practice. Most importantly, our profession is not performing architecturally when we design a house with a particular roof color to ensure it would not be mistaken with a Palestinian house and be attacked accidentally.

Keywords: apartheid, illegal architecture, occupation, politics

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Authors: Adedayo Adeleke, Dineo Pule

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The ongoing load-shedding in most parts of South Africa, combined with climate change causing severe drought conditions in Cape Town, has left electricity consumers seeking alternative sources of power and water. Solar energy, which is abundant in most parts of South Africa and is regarded as a clean and renewable source of energy, allows for the generation of electricity via solar photovoltaic systems. Rainwater harvesting is the collection and storage of rainwater from building rooftops, allowing people without access to water to collect it. The lack of dependable energy and water source must be addressed by shifting to solar energy via solar photovoltaic systems and rainwater harvesting. Before this can be done, the potential of building rooftops must be assessed to determine whether solar energy and rainwater harvesting will be able to meet or significantly contribute to Atlantis industrial areas' electricity and water demands. This research project presents methods and approaches for automatically extracting building rooftops in Atlantis industrial areas and evaluating their potential for solar photovoltaics and rainwater harvesting systems using Light Detection and Ranging (LiDAR) data and aerial imagery. The four objectives were to: (1) identify an optimal method of extracting building rooftops from aerial imagery and LiDAR data; (2) identify a suitable solar radiation model that can provide a global solar radiation estimate of the study area; (3) estimate solar photovoltaic potential overbuilding rooftop; and (4) estimate the amount of rainwater that can be harvested from the building rooftop in the study area. Mapflow, a plugin found in Quantum Geographic Information System(GIS) was used to automatically extract building rooftops using aerial imagery. The mean annual rainfall in Cape Town was obtained from a 29-year rainfall period (1991- 2020) and used to calculate the amount of rainwater that can be harvested from building rooftops. The potential for rainwater harvesting and solar photovoltaic systems was assessed, and it can be concluded that there is potential for these systems but only to supplement the existing resource supply and offer relief in times of drought and load-shedding.

Keywords: roof potential, rainwater harvesting, urban plan, roof extraction

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Authors: İlhami Karahanoglu, Oguz Ceylan

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As its well-known definitions; systemic risk refers to whole economic system down-turn movement even collapse together in very severe cases. In fact, it points out the contagion effects of the defaults. Such a risk is can be depicted with the famous Chinese game of falling domino stones. During and after the Bear & Sterns and Lehman Brothers cases, it was well understood that there is a very strong effect of systemic risk in financial services sector. In this study, we concentrate on the existence of systemic risk in Turkish Banking Sector based upon the Halkbank Case during the end month of 2013; there was a political turmoil in Turkey in which the close relatives of the upper politicians were involved in illegal trading activities. In that operation, the CEO of Halkbank was also arrested and in investigation, Halkbank was considered as part of such illegal actions. That operation had an impact on Halkbanks stock value. The Halkbank stock value during that time interval decreased remarkably, the distributional profile of stock return changed and became more volatile as well as more skewed. In this study, the daily returns of 5 leading banks in Turkish banking sector were used to obtain 48 return distributions (for each month, 90-days-back stock value returns are used) of 5 banks for the period 12/2011-12/2013 (pre operation period) and 12/2013-12/2015 (post operation period). When those distributions are compared with timely manner, interestingly; the distribution of the 5 other leading banks in Turkey, public or private, had also distribution profiles which was different from the past 2011-2013 period just like Halkbank. Those 5 big banks, whose stock values are monitored with sub index in Istanbul stock exchange (BIST) as BN10, had more skewed distribution just following the Halkbank stock return movement during the post operation period, with lover mean value and as well higher volatility. In addition, the correlation between the stock value return distributions of the leading banks after Halkbank case, where the returns are more skewed to the left, increased (which is measured in monthly base before and after the operation). The dependence between those banks was stronger under the case where the stock values were falling compared with the normal market condition. Such distributional effect of stock returns between the leading banks in Turkey, which is valid for down sub-market (financial/banking sector) condition, can be evaluated as an evidence for the existence of contagious effect and systemic risk.

Keywords: financial risk, systemic risk, banking sector, return distribution, dependency structure

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Authors: Alexander E. Hramov, Vadim V. Grubov, Alexey A. Koronovskii, Maria K. Kurovskaуa, Anastasija E. Runnova

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The perception of visual signals in the brain was among the first issues discussed in terms of multistability which has been introduced to provide mechanisms for information processing in biological neural systems. In this work the influence of the cognitive noise on the visual perception of multistable pictures has been investigated. The study includes an experiment with the bistable Necker cube illusion and the theoretical background explaining the obtained experimental results. In our experiments Necker cubes with different wireframe contrast were demonstrated repeatedly to different people and the probability of the choice of one of the cubes projection was calculated for each picture. The Necker cube was placed at the middle of a computer screen as black lines on a white background. The contrast of the three middle lines centered in the left middle corner was used as one of the control parameter. Between two successive demonstrations of Necker cubes another picture was shown to distract attention and to make a perception of next Necker cube more independent from the previous one. Eleven subjects, male and female, of the ages 20 through 45 were studied. The choice of the Necker cube projection was detected with the Electroencephalograph-recorder Encephalan-EEGR-19/26, Medicom MTD. To treat the experimental results we carried out theoretical consideration using the simplest double-well potential model with the presence of noise that led to the Fokker-Planck equation for the probability density of the stochastic process. At the first time an analytical solution for the probability of the selection of one of the Necker cube projection for different values of wireframe contrast have been obtained. Furthermore, having used the results of the experimental measurements with the help of the method of least squares we have calculated the value of the parameter corresponding to the cognitive noise of the person being studied. The range of cognitive noise parameter values for studied subjects turned to be [0.08; 0.55]. It should be noted, that experimental results have a good reproducibility, the same person being studied repeatedly another day produces very similar data with very close levels of cognitive noise. We found an excellent agreement between analytically deduced probability and the results obtained in the experiment. A good qualitative agreement between theoretical and experimental results indicates that even such a simple model allows simulating brain cognitive dynamics and estimating important cognitive characteristic of the brain, such as brain noise.

Keywords: bistability, brain, noise, perception, stochastic processes

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Authors: Masahiro Takimoto

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The present study explored how the metaphor awareness-raising approach affects the involvement of the right hemisphere in developing EFL learners’ knowledge regarding the different degrees of politeness embedded within different request expressions. The present study was motivated by theoretical considerations regarding the conceptual projection and the metaphorical idea of politeness is distance, as proposed; this study applied these considerations to develop Japanese learners’ knowledge regarding the different politeness degrees and to explore the connection between the metaphorical concept projection and right-hemisphere dominance. Japanese EFL learners do not know certain language strategies (e.g., English requests can be mitigated with biclausal downgraders, including the if-clause with past-tense modal verbs) and have difficulty adjusting the politeness degrees attached to request expressions according to situations. The present study used a pre/post-test design to reaffirm the efficacy of the cognitive technique and its connection to right-hemisphere involvement by mouth asymmetry technique. Mouth asymmetry measurement has been utilized because speech articulation, normally controlled mainly by one side of the brain, causes muscles on the opposite side of the mouth to move more during speech production. The present research did not administer the delayed post-test because it emphasized determining whether metaphor awareness-raising approaches for developing EFL learners’ pragmatic proficiency entailed right-hemisphere activation. Each test contained an acceptability judgment test (AJT) along with a speaking test in the post-test. The study results show that the metaphor awareness-raising group performed significantly better than the control group with regard to acceptability judgment and speaking tests post-test. These data revealed that the metaphor awareness-raising approach could promote L2 learning because it aided input enhancement and concept projection; through these aspects, the participants were able to comprehend an abstract concept: the degree of politeness in terms of the spatial concept of distance. Accordingly, the proximal-distal metaphor enabled the study participants to connect the newly spatio-visualized concept of distance to the different politeness degrees attached to different request expressions; furthermore, they could recall them with the left side of the mouth being wider than the right. This supported certain findings from previous studies that indicated the possible involvement of the brain's right hemisphere in metaphor processing.

Keywords: metaphor awareness-raising, right hemisphere, L2 politeness, mouth asymmetry

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Authors: Hee Yong Kang, Hyeon Ho Shin, Jung Cheol Yoo, Il Taek Lee, Sung Mo Yang

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Lightweight technology using composites is being developed for vehicle seat structures, and its design must meet the safety requirements. According to the Federal Motor Vehicle Safety Standard (FMVSS) 207 seating systems test procedure, the back moment load is applied to the seat back frame structure for the safety evaluation of the vehicle seat. The seat back frame using the composites is divided into three parts: upper part frame, and left- and right-side frame parts following the manufacturing process. When a rear moment load is applied to the seat back frame, the side frame receives the bending load and the torsional load at the same time. This results in the largest loaded strength. Therefore, strength test of the component unit is required. In this study, a component test method based on the FMVSS 207 seating systems test procedure was proposed for the strength analysis of bending load and torsional load of the automotive Bulk Molding Compound (BMC) Seat Back Side Frame. Moreover, strength evaluation according to the carbon band reinforcement was performed. The back-side frame parts of the seat that are applied to the test were manufactured through BMC that is composed of vinyl ester Matrix and short carbon fiber. Then, two kinds of reinforced and non-reinforced parts of carbon band were formed through a high-temperature compression molding process. In addition, the structure that is applied to the component test was constructed by referring to the FMVSS 207. Then, the bending load and the torsional load were applied through the displacement control to perform the strength test for four load conditions. The results of each test are shown through the load-displacement curves of the specimen. The failure strength of the parts caused by the reinforcement of the carbon band was analyzed. Additionally, the fracture characteristics of the parts for four strength tests were evaluated, and the weakness structure of the back-side frame of the seat structure was confirmed according to the test conditions. Through the bending and torsional strength test methods, we confirmed the strength and fracture characteristics of BMC Seat Back Side Frame according to the carbon band reinforcement. And we proposed a method of testing the part strength of a seat back frame for vehicles that can meet the FMVSS 207.

Keywords: seat back frame, bending and torsional strength, BMC (Bulk Molding Compound), FMVSS 207 seating systems

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Authors: Ioanna H. Lioliou, Despoina D. Zavraka

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The radical reformation that Greek urban space, has undergone over the last century, due to the socio-historical developments, technological development and political–geographic factors, has left its imprint on the urban landscape. While the big cities struggle to regain urban landscape balance, small towns are considered to offer high quality lifescapes, ensuring sustainable development potential. However, their unplanned urbanization process led to the loss of significant areas of nature, lack of essential infrastructure, chaotic built environment, incompatible land uses and urban cohesiveness. Natural environment reference points, such as springs, streams, rivers, forests, suburban greenbelts, and etc.; seems to be detached from urban space, while the public, open and green spaces, unequally distributed in the built environment, they are no longer able to offer a complete experience of nature in the city. This study focuses on Greek mainland, a small town Elassona, and aims to restore spatial coherence between the city’s homonymous river and its urban space surroundings. The existence of a linear aquatic ecosystem, is considered a precious greenway, also referred as blueway, able to initiate natural penetrations and ecosystems empowering. The integration of disconnected natural ecosystems forms the basis of a strategic intervention scheme, where the river becomes the urban integration tool / feature, constituting the main urban corridor and an indispensible part of a wider green network that connects open and green spaces, ensuring the function of all the established networks (transportation, commercial, social) of the town. The proposed intervention, introduces a green network highlighting the old stone bridge at the ‘entrance’ of the river in the town and expanding throughout the town with strategic uses and activities, providing accessibility for all the users. The methodology used, is based on the collection of design tools used in related urban river-design interventions around the world. The reinstallation/reactivation of the balance between natural and urban landscape, besides the environmental benefits, contributes decisively to the illustration/projection of urban green identity and re-enhancement of the quality of lifescape qualities and social interaction.

Keywords: green network, rehabilitation scheme, urban landscape, urban streams

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Authors: Florian Kiebert, Hagen Schmidt

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Standing surface acoustic waves (sSAWs) have already been used to manipulate particles in a microfluidic channel made of polydimethylsiloxan (PDMS). Usually two identical facing interdigital transducers (IDTs) are exploited to form an sSAW. Further, it has been reported that an sSAW can be generated by a single IDT using a superstrate resonating cavity or a PDMS post. Nevertheless, both setups utilising a traveling surface acoustic wave (tSAW) to create an sSAW for particle manipulation are costly. We present a simplified setup with a tSAW and a PDMS channel to form an sSAW. The incident tSAW is reflected at the rear PDMS channel wall and superimposed with the reflected tSAW. This superpositioned waves generates an sSAW but only at regions where the distance to the rear channel wall is smaller as the attenuation length of the tSAW minus the channel width. Therefore in a channel of 500µm width a tSAW with a wavelength λ = 120 µm causes a sSAW over the whole channel, whereas a tSAW with λ = 60 µm only forms an sSAW next to the rear wall of the channel, taken into account the attenuation length of a tSAW in water. Hence, it is possible to concentrate and trap particles in a defined region of the channel by adjusting the relation between the channel width and tSAW wavelength. Moreover, it is possible to generate a particle gradient over the channel width by picking the right ratio between channel wall and wavelength. The particles are moved towards the rear wall by the acoustic streaming force (ASF) and the acoustic radiation force (ARF) caused by the tSAW generated bulk acoustic wave (BAW). At regions in the channel were the sSAW is dominating the ARF focuses the particles in the pressure nodes formed by the sSAW caused BAW. On the one side the ARF generated by the sSAW traps the particle at the center of the tSAW beam, i. e. of the IDT aperture. On the other side, the ASF leads to two vortices, one on the left and on the right side of the focus region, deflecting the particles out of it. Through variation of the applied power it is possible to vary the number of particles trapped in the focus points, because near to the rear wall the amplitude of the reflected tSAW is higher and, therefore, the ARF of the sSAW is stronger. So in the vicinity of the rear wall the concentration of particles is higher but decreases with increasing distance to the wall, forming a gradient of particles. The particle gradient depends on the applied power as well as on the flow rate. Thus by variation of these two parameters it is possible to change the particle gradient. Furthermore, we show that the particle gradient can be modified by changing the relation between the channel width and tSAW wavelength. Concluding a single IDT generates an sSAW in a PDMS microchannel enables particle gradient generation in a well-defined microfluidic flow system utilising the ARF and ASF of a tSAW and an sSAW.

Keywords: ARF, ASF, particle manipulation, sSAW, tSAW

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Authors: Alvarez Barrantes, Robert Dorrell, Christopher Hackney, Anne Baar, Roberto Fernandez, Daniel Parsons

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Microplastic particles entering fluvial environments are deposited with natural sediments. Their settling properties can change by the absorption or adsorption of contaminants, organic matter, and organisms. These deposits include positively, neutrally, and negatively buoyant particles. This study aims to understand how plastic particles of different densities interact with natural sediments as they settle and how they are stored within the sediment deposit. The results of this study contribute to a better understanding of the deposition of microplastic particles and associated pollution in rivers. A set of 48 experiments was designed to investigate the settling process of microplastic particles in freshwater. The experimental work describes the vertical variation of cohesive and/or non-cohesive sediment versus microplastic densities in deposited sediment. The experiment consisted of adding microplastic particles, sediment, and water in a waterproof carton tube of a height of 24 cm and a diameter of 5 cm. The plastic selected is positively, neutrally, and negatively buoyant. The sediments consist of sand and clay with four different concentrations. The mixture of materials was shaken until is thoroughly mixed and left to settle for 24 hours. After the settlement, the tubes were frozen at -20 °C to be able to cut them and measure the thickness of the deposits and analyze the sediment and plastic distribution. The most representative experiments were repeated in a glass tube of the same size; to analyse the influences of current flows and depositional process. Finally, the glass tube experiments were used to study organic materials adsorption in plastic, settling the sample for four months. Defined microplastic layers were identified as the density of the plastic change. Preliminary results show that most of the positive buoyancy particles floated, neutral buoyancy particles form a layer above the sediment and negative buoyancy particles mixed with the sediment. The vertical grain size distribution of the deposits was analysed to determine deposition variation with and without plastic. It is expected that the positively buoyant particles are trapped in the sediment by the currents flows and sink due to organic material adsorption. Finally, the experiments will explain how microplastic particles, including positively buoyant ones, are stored in natural sediment deposits.

Keywords: microplastic adsorption process, microplastic deposition in natural sediment, microplastic pollution in rivers, storages of positive buoyancy microplastic particles

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Authors: Janne Engblom, Elias Oikarinen

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A panel dataset is one that follows a given sample of individuals over time, and thus provides multiple observations on each individual in the sample. Panel data models include a variety of fixed and random effects models which form a wide range of linear models. A special case of panel data models are dynamic in nature. A complication regarding a dynamic panel data model that includes the lagged dependent variable is endogeneity bias of estimates. Several approaches have been developed to account for this problem. In this paper, the panel models were estimated using the Arellano-Bover/Blundell-Bond Generalized method of moments (GMM) estimator which is an extension of the Arellano-Bond model where past values and different transformations of past values of the potentially problematic independent variable are used as instruments together with other instrumental variables. The Arellano–Bover/Blundell–Bond estimator augments Arellano–Bond by making an additional assumption that first differences of instrument variables are uncorrelated with the fixed effects. This allows the introduction of more instruments and can dramatically improve efficiency. It builds a system of two equations—the original equation and the transformed one—and is also known as system GMM. In this study, Finnish housing price dynamics were examined empirically by using the Arellano–Bover/Blundell–Bond estimation technique together with ordinary OLS. The aim of the analysis was to provide a comparison between conventional fixed-effects panel data models and dynamic panel data models. The Arellano–Bover/Blundell–Bond estimator is suitable for this analysis for a number of reasons: It is a general estimator designed for situations with 1) a linear functional relationship; 2) one left-hand-side variable that is dynamic, depending on its own past realizations; 3) independent variables that are not strictly exogenous, meaning they are correlated with past and possibly current realizations of the error; 4) fixed individual effects; and 5) heteroskedasticity and autocorrelation within individuals but not across them. Based on data of 14 Finnish cities over 1988-2012 differences of short-run housing price dynamics estimates were considerable when different models and instrumenting were used. Especially, the use of different instrumental variables caused variation of model estimates together with their statistical significance. This was particularly clear when comparing estimates of OLS with different dynamic panel data models. Estimates provided by dynamic panel data models were more in line with theory of housing price dynamics.

Keywords: dynamic model, fixed effects, panel data, price dynamics

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Authors: Emil Iskandarov, Nazrin Agayeva

Abstract:

Background: The effectiveness of hormone suppressive therapy (HST) in patients with nodular goiter (NG) is controversial. The aim of this study was to identify the impact of long-time HST on the Quality of Life (QoL) of patients with NG. Material and Methods: A retrospective analysis of 146 patients with NG showed treated with HST showed that in 38,4% of cases, HST was not effective. Nodules were increased in size and moreover, and new nodules were developed. Statistical procedure identified the predictors of resistant nodules: only one nodule in the left lobe; nodule size >17mm; calcinate within the nodule. 174 patients with NG, by whom predictors of resistant nodules were established, were informed about the results of previous research and surgery was suggested. Eighty-eight patients (the basic group) agreed with surgery and thyroidectomy was led. 86 patients (control group) ignored the suggestion and wished to receive HST. 3, 6 and 12 months after starting HST; control group patients were examined. HST was non-effective and patients, due to developing symptoms, were operated on. Patients in both groups were followed up 3, 6 and 12 months after thyroidectomy. Quality of Life was checked with the SF-36 survey form and compared between groups. The statistical analysis was performed with the non-parametric Mann–Whitney U test and with the Student t-test. P values ＜0.05 were considered statistically significant. Results and Discussions: QoL of patients in the basic and control groups 3 months after surgery was almost the same. However, Emotional problems severely interfered with patients in a control group with normal social activities with family, friends, and neighbors. The causes were related to the non-effective HST treatment before surgery: stress for forgetting to take drugs timely every day for a long time; blood tests for thyroid hormone level; needle biopsies of nodules for cancer screening and regular ultrasound investigations, which showed that nodules not diminished in size. Changing the treatment method after 1-year non-effective HST and delayed surgery negatively impacted patient's QoL. Social role functioning and mental health in the control group were also impaired and the difference between the results in the basic group was statistically significant (p <0.05). Conclusion: Predictors, such as only one nodule, the width of nodules more than 17mm, and the existence of calcinate within the nodule, are able to forecast the resistant nodules. HST in patients with resistant nodules is non-effective and surgery is suggested in patients with resistant nodules in the thyroid gland. Long time HST has a negative impact on the QoL patient after surgery.

Keywords: thyroid gland, nodule, hormone suppressive therapy, quality of life

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