Search results for: cognitive burden
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2649

Search results for: cognitive burden

1779 A Parallel Algorithm for Solving the PFSP on the Grid

Authors: Samia Kouki

Abstract:

Solving NP-hard combinatorial optimization problems by exact search methods, such as Branch-and-Bound, may degenerate to complete enumeration. For that reason, exact approaches limit us to solve only small or moderate size problem instances, due to the exponential increase in CPU time when problem size increases. One of the most promising ways to reduce significantly the computational burden of sequential versions of Branch-and-Bound is to design parallel versions of these algorithms which employ several processors. This paper describes a parallel Branch-and-Bound algorithm called GALB for solving the classical permutation flowshop scheduling problem as well as its implementation on a Grid computing infrastructure. The experimental study of our distributed parallel algorithm gives promising results and shows clearly the benefit of the parallel paradigm to solve large-scale instances in moderate CPU time.

Keywords: grid computing, permutation flow shop problem, branch and bound, load balancing

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1778 Artificial Steady-State-Based Nonlinear MPC for Wheeled Mobile Robot

Authors: M. H. Korayem, Sh. Ameri, N. Yousefi Lademakhi

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To ensure the stability of closed-loop nonlinear model predictive control (NMPC) within a finite horizon, there is a need for appropriate design terminal ingredients, which can be a time-consuming and challenging effort. Otherwise, in order to ensure the stability of the control system, it is necessary to consider an infinite predictive horizon. Increasing the prediction horizon increases computational demand and slows down the implementation of the method. In this study, a new technique has been proposed to ensure system stability without terminal ingredients. This technique has been employed in the design of the NMPC algorithm, leading to a reduction in the computational complexity of designing terminal ingredients and computational burden. The studied system is a wheeled mobile robot (WMR) subjected to non-holonomic constraints. Simulation has been investigated for two problems: trajectory tracking and adjustment mode.

Keywords: wheeled mobile robot, nonlinear model predictive control, stability, without terminal ingredients

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1777 Designing Space through Narratives: The Role of the Tour Description in the Architectural Design Process

Authors: A. Papadopoulou

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When people are asked to provide an oral description of a space they usually provide a Tour description, which is a dynamic type of spatial narrative centered on the narrator’s body, rather than a Map description, which is a static type of spatial narrative focused on the organization of the space as seen from above. Also, subjects with training in the architecture discipline tend to adopt a Tour perspective of space when the narrative refers to a space they have actually experienced but tend to adopt a Map perspective when the narrative refers to a space they have merely imagined. This pilot study aims to investigate whether the Tour description, which is the most common mode in the oral descriptions of experienced space, is a cognitive perspective taken in the process of designing a space. The study investigates whether a spatial description provided by a subject with architecture training in the type of a Tour description would be accurately translated into a spatial layout by other subjects with architecture training. The subjects were given the Tour description in written form and were asked to make a plan drawing of the described space. The results demonstrate that when we conceive and design space we do not adopt the same rules and cognitive patterns that we adopt when we reconstruct space from our memory. As shown by the results of this pilot study, the rules that underlie the Tour description were not detected in the translation from narratives to drawings. In a different phase, the study also investigates how would subjects with architecture training describe space when forced to take a Tour perspective in their oral description of a space. The results of this second phase demonstrate that if intentionally taken, the Tour perspective leads to descriptions of space that are more detailed and focused on experiential aspects.

Keywords: architecture, design process, embodied cognition, map description, oral narratives, tour description

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1776 Effects of Turkish Classical Music on Cognitive Function, Depression and Quality of Life in Elderly

Authors: Rukiye Pinar Boluktas

Abstract:

According to 2015 statistics, in Turkey, 46% of older people live alone in their homes, 55% have poor health perceptions, 18% face poverty, and 43% are unhappy. Prevalence of depression is between 14% and 20%. In 2013, rate of suicide was 6.5. However, the most of older people prefer to live in their community although they are lonely, they face poverty, and face limitations as a result of chronic diseases and disabilities. Community based care for older people is also encouraged by Ministry of Health as it is more cost-effective. Music therapy is a simple, effective, safe, and nonpharmacologic intervention that may be used to decrease depression and to improve cognition, and health related quality of life (HRQOL). In Turkish culture, music is typically described as ‘food for soul’. This study aimed to investigate the effect of Turkish classical music songs in 32 community dwelling older people. Participants were received interventions two or three times per week, 50-60 min per session, for 8 weeks at a day health center. Each intervention session started listening music for 15-20 min to get remember songs, then followed singing songs as a group. Participants were assessed at baseline (week 0), and two follow-up at month 1 and month 2. Compared to baseline, at two follow-up, we observed that cognition improved, depression decreased, and SF-36 scores, including 8 domains and two summary scores increased. We conclude that an intervention comprising listening and singing Turkish classical music improve cognition, depression and HRQOL in older people.

Keywords: cognitive function, depression, elderly, quality of life, Turkish classical music

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1775 Perceptions of Cognitive Behavioural Therapy in Physiotherapy Management for Chronic Low Back Pain: A Qualitative Exploration of Stakeholder Views

Authors: Latifa Alenezi, Liz Croot, Janet Harris

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Chronic Low Back Pain (CLBP) is one of the most common and recurrent musculoskeletal problems that causes patients to access health care services frequently. The Bio-psychosocial Model emphasises that psychological, behavioural and social factors contribute to the development and persistence of CLBP. Cognitive behavioural therapy (CBT) is a psychological pain management strategy that can be used by physiotherapists treating chronic low back pain. However, evidence of the effectiveness of CBT for CLBP varies between different studies. The proposed study was preceded by a mixed methods systematic review that found that CBT has a beneficial effect for CLBP patients when compared to waiting list or other treatments; however, there is variation in effectiveness across different settings. Little is known about how CBT is applied by physiotherapists in physiotherapy settings. The interest of this study is directed towards generating an explanation and understanding of why, when, and how some physiotherapists make decisions and choose to apply CBT for CLBP patients, whereas others do not. Also, how and for what type of CLBP patients does CBT work, and for whom might CBT not work? Therefore, the study will take a qualitative approach to explore CLBP patients’, physiotherapists’ and managers’ perceptions of CBT and how it is used in physiotherapy to enable a deeper understanding and richer explanation of CBT effectiveness and help to inform research and practice. The study will use grounded theory approach to generate an explanatory theory of the clinical application of CBT for CLBP in physiotherapy settings. Physiotherapists, patients and managers of physiotherapy services will be interviewed. Grounded theory techniques will be used to analyse the data. The presentation will describe findings from the interviews and the emerging theory. This research will help to further inform RCTs about the effectiveness of CBT for CLBP in physiotherapy.

Keywords: CBT, CLBP, perception, physiotherapy, theory

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1774 Neuronal Mechanisms of Observational Motor Learning in Mice

Authors: Yi Li, Yinan Zheng, Ya Ke, Yungwing Ho

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Motor learning is a process that frequently happens among humans and rodents, which is defined as the changes in the capability to perform a skill that is conformed to have a relatively permanent improvement through practice or experience. There are many ways to learn a behavior, among which is observational learning. Observational learning is the process of learning by watching the behaviors of others, for example, a child imitating parents, learning a new sport by watching the training videos or solving puzzles by watching the solutions. Many research explores observational learning in humans and primates. However, the neuronal mechanism of which, especially observational motor learning, was uncertain. It’s well accepted that mirror neurons are essential in the observational learning process. These neurons fire when the primate performs a goal-directed action and sees someone else demonstrating the same action, which suggests they have high firing activity both completing and watching the behavior. The mirror neurons are assumed to mediate imitation or play a critical and fundamental role in action understanding. They are distributed in many brain areas of primates, i.e., posterior parietal cortex (PPC), premotor cortex (M2), and primary motor cortex (M1) of the macaque brain. However, few researchers report the existence of mirror neurons in rodents. To verify the existence of mirror neurons and the possible role in motor learning in rodents, we performed customised string-pulling behavior combined with multiple behavior analysis methods, photometry, electrophysiology recording, c-fos staining and optogenetics in healthy mice. After five days of training, the demonstrator (demo) mice showed a significantly quicker response and shorter time to reach the string; fast, steady and accurate performance to pull down the string; and more precisely grasping the beads. During three days of observation, the mice showed more facial motions when the demo mice performed behaviors. On the first training day, the observer reduced the number of trials to find and pull the string. However, the time to find beads and pull down string were unchanged in the successful attempts on the first day and other training days, which indicated successful action understanding but failed motor learning through observation in mice. After observation, the post-hoc staining revealed that the c-fos expression was increased in the cognitive-related brain areas (medial prefrontal cortex) and motor cortices (M1, M2). In conclusion, this project indicated that the observation led to a better understanding of behaviors and activated the cognitive and motor-related brain areas, which suggested the possible existence of mirror neurons in these brain areas.

Keywords: observation, motor learning, string-pulling behavior, prefrontal cortex, motor cortex, cognitive

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1773 Attention-based Adaptive Convolution with Progressive Learning in Speech Enhancement

Authors: Tian Lan, Yixiang Wang, Wenxin Tai, Yilan Lyu, Zufeng Wu

Abstract:

The monaural speech enhancement task in the time-frequencydomain has a myriad of approaches, with the stacked con-volutional neural network (CNN) demonstrating superiorability in feature extraction and selection. However, usingstacked single convolutions method limits feature represen-tation capability and generalization ability. In order to solvethe aforementioned problem, we propose an attention-basedadaptive convolutional network that integrates the multi-scale convolutional operations into a operation-specific blockvia input dependent attention to adapt to complex auditoryscenes. In addition, we introduce a two-stage progressivelearning method to enlarge the receptive field without a dra-matic increase in computation burden. We conduct a series ofexperiments based on the TIMIT corpus, and the experimen-tal results prove that our proposed model is better than thestate-of-art models on all metrics.

Keywords: speech enhancement, adaptive convolu-tion, progressive learning, time-frequency domain

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1772 Impulsivity, Emotional Regulation, Problematic Mukbang Watching and Eating Disorders in University Students

Authors: Aqsa Butt, Nida Zafar

Abstract:

The study assesses the relationship between impulsivity, emotional regulation, problematic mukbang watching, and eating disorders in university students. It was hypothesized there is likely to be a relationship between impulsivity, emotional regulation, problematic mukbang watching, and eating disorders in university students; impulsivity and emotional regulation would predict problematic mukbang watching in university students; problematic mukbang watching would predict eating disorders in university students. A correlational research design was used. A sample of 200 students was taken from different public and private universities in Lahore. Emotional regulation questionnaire (Gross & John, 2003), Abbreviated Barrat Impulsiveness Scale (Christopher et al., 2014), Problematic Mukbang Watching Scale (Kircaburun et al., 2020), and Eating Disorder Diagnostic Scale (Stice et al., 2004) were used for assessment. Results showed a significant positive relationship between impulsivity and expressive suppression with problematic mukbang watching. However, there is a significant negative relationship between cognitive reappraisal and problematic mukbang watching. Problematic mukbang is significantly positively related to bulimia nervosa and binge eating. Furthermore, impulsivity and expressive suppression are significant positive predictors of problematic mukbang watching, and cognitive reappraisal is a significant negative predictor of problematic mukbang watching. Additionally, problematic mukbang watching significantly positively predicts bulimia nervosa and binge eating. The research has important implications for university students to understand that excessive watching of such videos can lead to eating disorders such as bulimia nervosa and binge eating. This research provides an understanding of the effects of Mukbang watching, and it also adds to the existing body of knowledge on eating disorders.

Keywords: impulsivity, emotional regulation, problematic Mukbang watching eating disorders, students

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1771 A Context Aware Mobile Learning System with a Cognitive Recommendation Engine

Authors: Jalal Maqbool, Gyu Myoung Lee

Abstract:

Using smart devices for context aware mobile learning is becoming increasingly popular. This has led to mobile learning technology becoming an indispensable part of today’s learning environment and platforms. However, some fundamental issues remain - namely, mobile learning still lacks the ability to truly understand human reaction and user behaviour. This is due to the fact that current mobile learning systems are passive and not aware of learners’ changing contextual situations. They rely on static information about mobile learners. In addition, current mobile learning platforms lack the capability to incorporate dynamic contextual situations into learners’ preferences. Thus, this thesis aims to address these issues highlighted by designing a context aware framework which is able to sense learner’s contextual situations, handle data dynamically, and which can use contextual information to suggest bespoke learning content according to a learner’s preferences. This is to be underpinned by a robust recommendation system, which has the capability to perform these functions, thus providing learners with a truly context-aware mobile learning experience, delivering learning contents using smart devices and adapting to learning preferences as and when it is required. In addition, part of designing an algorithm for the recommendation engine has to be based on learner and application needs, personal characteristics and circumstances, as well as being able to comprehend human cognitive processes which would enable the technology to interact effectively and deliver mobile learning content which is relevant, according to the learner’s contextual situations. The concept of this proposed project is to provide a new method of smart learning, based on a capable recommendation engine for providing an intuitive mobile learning model based on learner actions.

Keywords: aware, context, learning, mobile

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1770 Evaluation of Commercials by Psychological Changes in Consumers’ Physiological Characteristics

Authors: Motoki Seguchi, Fumiko Harada, Hiromitsu Shimakawa

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There have been many local companies in countryside that carefully produce and sell products, which include crafts and foods produced with traditional methods. These companies are likely to use commercials to advertise their products. However, it is difficult for companies to judge whether the commercials they create are having an impact on consumers. Therefore, to create effective commercials, this study researches what kind of gimmicks in commercials affect what kind of consumers. This study proposes a method for extracting psychological change points from the physiological characteristics of consumers while they are watching commercials and estimating the gimmicks in the commercial that affect consumer engagement. In this method, change point detection is applied to pupil size for estimating gimmicks that affect consumers’ emotional engagement, and to EDA for estimating gimmicks that affect cognitive engagement. A questionnaire is also used to estimate the commercials that influence behavioral engagement. As a result of estimating the gimmicks that influence consumer engagement using this method, it was found that there are some common features among the gimmicks. To influence cognitive engagement, it was found that it was useful to include flashback scenes, messages to be appealed to, the company’s name, and the company’s logos as gimmicks. It was also found that flashback scenes and story climaxes were useful in influencing emotional engagement. Furthermore, it was found that the use of storytelling commercials may or may not be useful, depending on which consumers are desired to take which behaviors. It also estimated the gimmicks that influence consumers for each target and found that the useful gimmicks are slightly different for students and working adults. By using this method, it can understand which gimmicks in the commercial affect which engagement of the consumers. Therefore, the results of this study can be used as a reference for the gimmicks that should be included in commercials when companies create their commercials in the future.

Keywords: change point detection, estimating engagement, physiological characteristics, psychological changes, watching commercials

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1769 Risk and Emotion: Measuring the Effect of Emotion and Other Visceral Factors on Decision Making under Risk

Authors: Michael Mihalicz, Aziz Guergachi

Abstract:

Background: The science of modelling choice preferences has evolved over centuries into an interdisciplinary field contributing to several branches of Microeconomics and Mathematical Psychology. Early theories in Decision Science rested on the logic of rationality, but as it and related fields matured, descriptive theories emerged capable of explaining systematic violations of rationality through cognitive mechanisms underlying the thought processes that guide human behaviour. Cognitive limitations are not, however, solely responsible for systematic deviations from rationality and many are now exploring the effect of visceral factors as the more dominant drivers. The current study builds on the existing literature by exploring sleep deprivation, thermal comfort, stress, hunger, fear, anger and sadness as moderators to three distinct elements that define individual risk preference under Cumulative Prospect Theory. Methodology: This study is designed to compare the risk preference of participants experiencing an elevated affective or visceral state to those in a neutral state using nonparametric elicitation methods across three domains. Two experiments will be conducted simultaneously using different methodologies. The first will determine visceral states and risk preferences randomly over a two-week period by prompting participants to complete an online survey remotely. In each round of questions, participants will be asked to self-assess their current state using Visual Analogue Scales before answering a series of lottery-style elicitation questions. The second experiment will be conducted in a laboratory setting using psychological primes to induce a desired state. In this experiment, emotional states will be recorded using emotion analytics and used a basis for comparison between the two methods. Significance: The expected results include a series of measurable and systematic effects on the subjective interpretations of gamble attributes and evidence supporting the proposition that a portion of the variability in human choice preferences unaccounted for by cognitive limitations can be explained by interacting visceral states. Significant results will promote awareness about the subconscious effect that emotions and other drive states have on the way people process and interpret information, and can guide more effective decision making by informing decision-makers of the sources and consequences of irrational behaviour.

Keywords: decision making, emotions, prospect theory, visceral factors

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1768 Lubricating Grease from Waste Cooking Oil and Waste Motor Sludge

Authors: Aseem Rajvanshi, Pankaj Kumar Pandey

Abstract:

Increase in population has increased the demand of energy to fulfill all its needs. This will result in burden on fossil fuels especially crude oil. Waste oil due to its disposal problem creates environmental degradation. In this context, this paper studies utilization of waste cooking oil and waste motor sludge for making lubricating grease. Experimental studies have been performed by variation in time and concentration of mixture of waste cooking oil and waste motor sludge. The samples were analyzed using penetration test (ASTM D-217), dropping point (ASTM D-566), work penetration (ASTM D-217) and copper strip test (ASTM D-408). Among 6 samples, sample 6 gives the best results with a good drop point and a fine penetration value. The dropping point and penetration test values were found to be 205 °C and 315, respectively. The penetration value falls under the category of NLGI (National Lubricating Grease Institute) consistency number 1.

Keywords: crude oil, copper strip corrosion test, dropping point, penetration test

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1767 Positive-Negative Asymmetry in the Evaluations of Political Candidates: The Mediating Role of Affect in the Relationship between Cognitive Evaluation and Voting Intention

Authors: Magdalena Jablonska, Andrzej Falkowski

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The negativity effect is one of the most intriguing and well-studied psychological phenomena that can be observed in many areas of human life. The aim of the following study is to investigate how valence framing and positive and negative information about political candidates affect judgments about similarity to an ideal and bad politician. Based on the theoretical framework of features of similarity, it is hypothesized that negative features have a stronger effect on similarity judgments than positive features of comparable value. Furthermore, the mediating role of affect is tested. Method: One hundred sixty-one people took part in an experimental study. Participants were divided into 6 research conditions that differed in the reference point (positive vs negative framing) and the number of favourable and unfavourable information items about political candidates (a positive, neutral and negative candidate profile). In positive framing condition, the concept of an ideal politician was primed; in the negative condition, participants were to think about a bad politician. The effect of independent variables on similarity judgments, affective evaluation, and voting intention was tested. Results: In the positive condition, the analysis showed that the negative effect of additional unfavourable features was greater than the positive effect of additional favourable features in judgements about similarity to the ideal candidate. In negative framing condition, ANOVA was insignificant, showing that neither the addition of positive features nor additional negative information had a significant impact on the similarity to a bad political candidate. To explain this asymmetry, two mediational analyses were conducted that tested the mediating role of affect in the relationship between similarity judgments and voting intention. In both situations the mediating effect was significant, but the comparison of two models showed that the mediation was stronger for a negative framing. Discussion: The research supports the negativity effect and attempts to explain the psychological mechanism behind the positive-negative asymmetry. The results of mediation analyses point to a stronger mediating role of affect in the relationship between cognitive evaluation and voting intention. Such a result suggests that negative comparisons, leading to the activation of negative features, give rise to stronger emotions than positive features of comparable strength. The findings are in line with positive-negative asymmetry, however, by adopting Tversky’s framework of features of similarity, the study integrates the cognitive mechanism of the negativity effect delineated in the contrast model of similarity with its emotional component resulting from the asymmetrical effect of positive and negative emotions on decision-making.

Keywords: affect, framing, negativity effect, positive-negative asymmetry, similarity judgements

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1766 The Influence of Minority Stress on Depression among Thai Lesbian, Gay, Bisexual, and Transgender Adults

Authors: Priyoth Kittiteerasack, Alana Steffen, Alicia K. Matthews

Abstract:

Depression is a leading cause of the worldwide burden of disability and disease burden. Notably, lesbian, gay, bisexual, and transgender (LGBT) populations are more likely to be a high-risk group for depression compared to their heterosexual and cisgender counterparts. To date, little is known about the rates and predictors of depression among Thai LGBT populations. As such, the purpose of this study was to: 1) measure the prevalence of depression among a diverse sample of Thai LGBT adults and 2) determine the influence of minority stress variables (discrimination, victimization, internalized homophobia, and identity concealment), general stress (stress and loneliness), and coping strategies (problem-focused, avoidance, and seeking social support) on depression outcomes. This study was guided by the Minority Stress Model (MSM). The MSM posits that elevated rates of mental health problems among LGBT populations stem from increased exposures to social stigma due to their membership in a stigmatized minority group. Social stigma, including discrimination and violence, represents unique sources of stress for LGBT individuals and have a direct impact on mental health. This study was conducted as part of a larger descriptive study of mental health among Thai LGBT adults. Standardized measures consistent with the MSM were selected and translated into the Thai language by a panel of LGBT experts using the forward and backward translation technique. The psychometric properties of translated instruments were tested and acceptable (Cronbach’s alpha > .8 and Content Validity Index = 1). Study participants were recruited using convenience and snowball sampling methods. Self-administered survey data were collected via an online survey and via in-person data collection conducted at a leading Thai LGBT organization. Descriptive statistics and multivariate analyses using multiple linear regression models were conducted to analyze study data. The mean age of participants (n = 411) was 29.5 years (S.D. = 7.4). Participants were primarily male (90.5%), homosexual (79.3%), and cisgender (76.6%). The mean score for depression of study participant was 9.46 (SD = 8.43). Forty-three percent of LGBT participants reported clinically significant levels of depression as measured by the Beck Depression Inventory. In multivariate models, the combined influence of demographic, stress, coping, and minority stressors explained 47.2% of the variance in depression scores (F(16,367) = 20.48, p < .001). Minority stressors independently associated with depression included discrimination (β = .43, p < .01) victimization (β = 1.53, p < .05), and identity concealment (β = -.54, p < .05). In addition, stress (β = .81, p < .001), history of a chronic disease (β = 1.20, p < .05), and coping strategies (problem-focused coping β = -1.88, p < .01, seeking social support β = -1.12, p < .05, and avoidance coping β = 2.85, p < .001) predicted depression scores. The study outcomes emphasized that minority stressors uniquely contributed to depression levels among Thai LGBT participants over and above typical non-minority stressors. Study findings have important implications for nursing practice and the development of intervention research.

Keywords: depression, LGBT, minority stress, sexual and gender minority, Thailand

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1765 Psychosocial Challenges of Multi-Drug Resistant Tuberculosis (MDR-TB) Patients at St. Peter TB Specialized Hospital in Addis Ababa

Authors: Tamrat Girma Biru

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Multidrug-resistant tuberculosis (MDR-TB) is defined as resistant to at least Refampicin and Isoniazed: the most two power full TB drugs. It is a leading cause of high rates of morbidity and mortality, and increasing psychosocial challenges to patients, especially when co-infected with Human Immunodeficiency Virus (HIV). Ethiopia faces the highest rates of MDR-TB infection in the world. Objectives: The main objective of this study was to identify the psychosocial challenges of MDR-TB patients, to investigate the extent of the psychosocial challenges on (self-esteem, depression, and stigma) that MDR-TB patients encounter, to examine whether there is a sex difference in experiencing psychosocial challenges and assess the counseling needs of MDR-TB patients. Methodology: A cross-sectional study was conducted at St. Peter TB Specialized Hospital, Addis Ababa on 40 patients (25 males and 15 females) who are hospitalized for treatment. The patients were identified by using purposive sampling and made fill a questionnaire measuring their level of self-esteem, depression and stigma. Besides, data were collected from 16 participants, 28 care providers and 8 guardians, using semi-structured interview. The obtained data were analyzed using SPSS statistical program, descriptive statistics, independent t-test, and qualitative description. Results and Discussion: The results of the study showed that the majority (80%) of the respondents had suffered psychological challenges and social discriminations. Thus, the significance of MDR-TB and its association with HIV/AIDS problems is considered. Besides the psychosocial challenges, various aggravating factors such as length of treatment, drug burden and insecurity in economy together highly challenges the life of patients. In addition, 60% of participants showed low level of self-esteem. The patients also reported that they experienced high self-stigma and stigma by other members of the society. The majority of the participants (75%) showed moderate and severe level of depression. In terms of sex there is no difference between the mean scores of males and females in the level of depression and stigmatization by others and by themselves. But females showed lower level of self-esteem than males. The analysis of the t-test also shows that there were no statistically significant sex difference on the level of depression and stigma. Based on the qualitative data MDR-TB patients face various challenges in their life sphere such as: Psychological (depression, low self value, lowliness, anxiety), social (stigma, isolation from social relations, self-stigmatization,) and medical (drug side effect, drug toxicity, drug burden, treatment length, hospital stays). Recommendations: Based on the findings of this study possible recommendations were forwarded: develop and extend MDR-TB disease awareness creation through by media (printing and electronic), school net TB clubs, and door to door community education. Strengthen psychological wellbeing and social relationship of MDR-TB patients using proper and consistent psychosocial support and counseling. Responsible bodies like Ministry of Health (MOH) and its stakeholders and Non Governmental Organizations (NGOs) need to assess the challenges of patients and take measures on this pressing issue.

Keywords: psychosocial challenges, counseling, multi-drug resistant tuberculosis (MDR-TB), tuberculosis therapy

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1764 Parenting a Child with Profound Disabilities in Developing Countries: Experiences from Bangladesh

Authors: M. Abdul Jalil

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Parents caring for a child with a profound disability encounter different experiences compared to the parents caring for a child without a disability. The aim of this paper is to develop a greater understanding of parenting of a child with profound disabilities in the context of developing countries with reference to Bangladesh. The paper reveals that parents caring for a child with a profound disability are experiencing increased financial burden, affiliate and courtesy stigma and negative impact on mothers in terms of additional caregiving role, instability of conjugal relations, giving up of involvement in economic activities, and shrinking kinship and social relationships. In addition, government and non-government services for children with disabilities are very limited. Moreover, the information about the services is also not available to the parents. Therefore, parents find it difficult to cope with the challenges that lead to the alienation of the parents. The paper recommended the strategies to address the issues in the context of Bangladesh, which in turn might be applicable to the developing countries as well.

Keywords: caregiving, coping, parenting, profound disability

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1763 Time-dependent Association between Recreational Cannabinoid Use and Memory Performance in Healthy Adults: A Neuroimaging Study of Human Connectome Project

Authors: Kamyar Moradi

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Background: There is mixed evidence regarding the association between recreational cannabinoid use and memory performance. One of the major reasons for the present controversy is different cannabinoid use-related covariates that influence the cognitive status of an individual. Adjustment of these confounding variables provides accurate insight into the real effects of cannabinoid use on memory status. In this study, we sought to investigate the association between recent recreational cannabinoid use and memory performance while correcting the model for other possible covariates such as demographic characteristics and duration, and amount of cannabinoid use. Methods: Cannabinoid users were assigned to two groups based on the results of THC urine drug screen test (THC+ group: n = 110, THC- group: n = 410). THC urine drug screen test has a high sensitivity and specificity in detecting cannabinoid use in the last 3-4 weeks. The memory domain of NIH Toolbox battery and brain MRI volumetric measures were compared between the groups while adjusting for confounding variables. Results: After Benjamini-Hochberg p-value correction, the performance in all of the measured memory outcomes, including vocabulary comprehension, episodic memory, executive function/cognitive flexibility, processing speed, reading skill, working memory, and fluid cognition, were significantly weaker in THC+ group (p values less than 0.05). Also, volume of gray matter, left supramarginal, right precuneus, right inferior/middle temporal, right hippocampus, left entorhinal, and right pars orbitalis regions were significantly smaller in THC+ group. Conclusions: this study provides evidence regarding the acute effect of recreational cannabis use on memory performance. Further studies are warranted to confirm the results.

Keywords: brain MRI, cannabis, memory, recreational use, THC urine test

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1762 Investigating Role of Traumatic Events in a Pakistani Sample

Authors: Khadeeja Munawar, Shamsul Haque

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The claim that traumatic events influence the recalled memories and mental health has received mixed empirical support. This study examines the memories of a sample drawn from Pakistan, a country that has witnessed many life-changing socio-political events, wars, and natural disasters in 72 years of its history. A sample of 210 senior citizens (Mage = 64.35, SD = 6.33) was recruited from Pakistan. The aim was to investigate if participants retrieved more memories related to past traumatic events using a word-cueing technique. Each participant reported ten memories to ten neutral cue words. The results revealed that past traumatic events were not adversely affecting the memories and mental health of participants. When memories were plotted with respect to the ages at which the events happened, a pronounced bump at 11-20 years of age was seen. Memories within as well as outside of the bump were mostly positive. The multilevel logistic regression modelling showed that the memories recalled were personally important and played a role in enhancing resilience. The findings revealed that despite facing an array of ethnic, religious, political, economic, and social conflicts, the participants were resilient, recalled predominantly positive memories, and had intact mental health. The findings have clinical implications in Cognitive Behavioral Therapy (CBT). The patients can be made aware of their negative emotions, troublesome/traumatic memories, and the distorted thinking patterns and their memories can be restructured. The findings can also be used to teach Memory Specificity Training (MEST) by psycho-educating the patients around changes in memory functioning and enhancing the recall of memories, which are more specific, vivid, and filled with sensory details.

Keywords: cognitive behavioral therapy, memories, mental health, resilience, trauma

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1761 The Interplay of Community-based Social Capital and Neighbourhood Dynamics in Enhancing SMEs’ Resilience During Crises: A Fuzzy-Set Qualitative Comparative Analysis Approach

Authors: Arash Sadeghi, Taimaz Larimian

Abstract:

This study explores the intricate interplay between community-based social capital (CBSC) and neighbourhood dynamics in enhancing resilience of Iranian SMEs, particularly under the strain of international sanctions. Utilising fuzzy-set Qualitative Comparative Analysis (fsQCA), we examine how different dimensions of CBSC—structural, relational, and cognitive—interact with neighbourhood socio-economic and built-environment characteristics to influence SME resilience. Findings reveal four configurations that contribute to the presence of resistance and five configurations associated with the adaptation outcome. Each configuration demonstrates a distinct combination of social capital elements, which vary according to the specific socio-economic and built-environmental characteristics of the neighbourhoods. The first configuration highlights the importance of structural social capital in deprived areas for building resistance, while the second emphasises the role of relational social capital in low-density, minimally deprived areas. Overall, cognitive social capital seems to be less effective in driving economic resilience compared to structural and relational types. This research contributes to the literature by providing a nuanced understanding of the synergistic effects of CBSC dimensions and neighbourhood characteristics on SME resilience. By adopting a configurational approach, we move beyond traditional methodologies, offering a comprehensive view of the complex dynamics of CBSC and neighbourhood characteristics and their impact on SME resilience in varying neighbourhoods.

Keywords: community-based social capital, fuzzy-set qualitative comparative analysis (fsQCA), place-based resilience, resistance

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1760 Subjective Probability and the Intertemporal Dimension of Probability to Correct the Misrelation Between Risk and Return of a Financial Asset as Perceived by Investors. Extension of Prospect Theory to Better Describe Risk Aversion

Authors: Roberta Martino, Viviana Ventre

Abstract:

From a theoretical point of view, the relationship between the risk associated with an investment and the expected value are directly proportional, in the sense that the market allows a greater result to those who are willing to take a greater risk. However, empirical evidence proves that this relationship is distorted in the minds of investors and is perceived exactly the opposite. To deepen and understand the discrepancy between the actual actions of the investor and the theoretical predictions, this paper analyzes the essential parameters used for the valuation of financial assets with greater attention to two elements: probability and the passage of time. Although these may seem at first glance to be two distinct elements, they are closely related. In particular, the error in the theoretical description of the relationship between risk and return lies in the failure to consider the impatience that is generated in the decision-maker when events that have not yet happened occur in the decision-making context. In this context, probability loses its objective meaning and in relation to the psychological aspects of the investor, it can only be understood as the degree of confidence that the investor has in the occurrence or non-occurrence of an event. Moreover, the concept of objective probability does not consider the inter-temporality that characterizes financial activities and does not consider the condition of limited cognitive capacity of the decision maker. Cognitive psychology has made it possible to understand that the mind acts with a compromise between quality and effort when faced with very complex choices. To evaluate an event that has not yet happened, it is necessary to imagine that it happens in your head. This projection into the future requires a cognitive effort and is what differentiates choices under conditions of risk and choices under conditions of uncertainty. In fact, since the receipt of the outcome in choices under risk conditions is imminent, the mechanism of self-projection into the future is not necessary to imagine the consequence of the choice and the decision makers dwell on the objective analysis of possibilities. Financial activities, on the other hand, develop over time and the objective probability is too static to consider the anticipatory emotions that the self-projection mechanism generates in the investor. Assuming that uncertainty is inherent in valuations of events that have not yet occurred, the focus must shift from risk management to uncertainty management. Only in this way the intertemporal dimension of the decision-making environment and the haste generated by the financial market can be cautioned and considered. The work considers an extension of the prospectus theory with the temporal component with the aim of providing a description of the attitude towards risk with respect to the passage of time.

Keywords: impatience, risk aversion, subjective probability, uncertainty

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1759 Enunciation on Complexities of Selected Tree Searching Algorithms

Authors: Parag Bhalchandra, S. D. Khamitkar

Abstract:

Searching trees is a most interesting application of Artificial Intelligence. Over the period of time, many innovative methods have been evolved to better search trees with respect to computational complexities. Tree searches are difficult to understand due to the exponential growth of possibilities when increasing the number of nodes or levels in the tree. Usually it is understood when we traverse down in the tree, traverse down to greater depth, in the search of a solution or a goal. However, this does not happen in reality as explicit enumeration is not a very efficient method and there are many algorithmic speedups that will find the optimal solution without the burden of evaluating all possible trees. It was a common question before all researchers where they often wonder what algorithms will yield the best and fastest result The intention of this paper is two folds, one to review selected tree search algorithms and search strategies that can be applied to a problem space and the second objective is to stimulate to implement recent developments in the complexity behavior of search strategies. The algorithms discussed here apply in general to both brute force and heuristic searches.

Keywords: trees search, asymptotic complexity, brute force, heuristics algorithms

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1758 Pathway and Differential Gene Expression Studies for Colorectal Cancer

Authors: Ankita Shukla, Tiratha Raj Singh

Abstract:

Colorectal cancer (CRC) imposes serious mortality burden worldwide and it has been increasing for past consecutive years. Continuous efforts have been made so far to diagnose the disease condition and to identify the root cause for it. In this study, we performed the pathway level as well as the differential gene expression studies for CRC. We analyzed the gene expression profile GSE24514 from Gene Expression Omnibus (GEO) along with the gene pathways involved in the CRC. This analysis helps us to understand the behavior of the genes that have shown differential expression through their targeted pathways. Pathway analysis for the targeted genes covers the wider area which therefore decreases the possibility to miss the significant ones. This will prove to be beneficial to expose the ones that have not been given attention so far. Through this analysis, we attempt to understand the various neighboring genes that have close relationship to the targeted one and thus proved to be significantly controlling the CRC. It is anticipated that the identified hub and neighboring genes will provide new directions to look at the pathway level differently and will be crucial for the regulatory processes of the disease.

Keywords: mismatch repair, microsatellite instability, carcinogenesis, morbidity

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1757 Looking beyond Lynch's Image of a City

Authors: Sandhya Rao

Abstract:

Kevin Lynch’s Theory on Imeageability, let on explore a city in terms of five elements, Nodes, Paths, Edges, landmarks and Districts. What happens when we try to record the same data in an Indian context? What happens when we apply the same theory of Imageability to a complex shifting urban pattern of the Indian cities and how can we as Urban Designers demonstrate our role in the image building ordeal of these cities? The organizational patterns formed through mental images, of an Indian city is often diverse and intangible. It is also multi layered and temporary in terms of the spirit of the place. The pattern of images formed is loaded with associative meaning and intrinsically linked with the history and socio-cultural dominance of the place. The embedded memory of a place in one’s mind often plays an even more important role while formulating these images. Thus while deriving an image of a city one is often confused or finds the result chaotic. The images formed due to its complexity are further difficult to represent using a single medium. Under such a scenario it’s difficult to derive an output of an image constructed as well as make design interventions to enhance the legibility of a place. However, there can be a combination of tools and methods that allows one to record the key elements of a place through time, space and one’s user interface with the place. There has to be a clear understanding of the participant groups of a place and their time and period of engagement with the place as well. How we can translate the result obtained into a design intervention at the end, is the main of the research. Could a multi-faceted cognitive mapping be an answer to this or could it be a very transient mapping method which can change over time, place and person. How does the context influence the process of image building in one’s mind? These are the key questions that this research will aim to answer.

Keywords: imageability, organizational patterns, legibility, cognitive mapping

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1756 Ophthalmic Services Covered by Albasar International Foundation in Sudan

Authors: Mohammad Ibrahim

Abstract:

The study was conducted at Albasar international foundation ophthalmic hospitals in Sudan to study the burden and patterns of ophthalmic disorder in the sector. Review of the hospitals records revealed that the total number of patient examined in the hospitals and outreached camps conducted by the hospitals is 10,513,874, the total number of surgeries is 694,015 and the total number of pupils at school program is 230,382. The organization working with the highest management system and standards and quality result based planning. The study yielded that the ophthalmic problem in Sudan are of great percentage and the temporal blindness disorder are high since major cases and surgeries were Cataract (57.8%). Retinal problem (2.9%), Glaucoma (2.4%), Orbit and Occulo-plastic disorders (2.2%) other disorders are refractive errors, squint and strabismus, Corneal, Pediatrics and minor ophthalmic disorders.

Keywords: hospitals and outreach ophthalmic services, largest coverage of ophthalmic services, nonprofitable ophthalmic services, strong management system and standards

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1755 Protective Effect of the Histamine H3 Receptor Antagonist DL77 in Behavioral Cognitive Deficits Associated with Schizophrenia

Authors: B. Sadek, N. Khan, D. Łażewska, K. Kieć-Kononowicz

Abstract:

The effects of the non-imidazole histamine H3 receptor (H3R) antagonist DL77 in passive avoidance paradigm (PAP) and novel object recognition (NOR) task in MK801-induced cognitive deficits associated with schizophrenia (CDS) in adult male rats, and applying donepezil (DOZ) as a reference drug were investigated. The results show that acute systemic administration of DL77 (2.5, 5, and 10 mg/kg, i.p.) significantly improved MK801-induced (0.1 mg/kg, i.p.) memory deficits in PAP. The ameliorating activity of DL77 (5 mg/kg, i.p.) in MK801-induced deficits was partly reversed when rats were pretreated with the centrally-acting H2R antagonist zolantidine (ZOL, 10 mg/kg, i.p.) or with the antimuscarinic antagonist scopolamine (SCO, 0.1 mg/kg, i.p.), but not with the CNS penetrant H1R antagonist pyrilamine (PYR, 10 mg/kg, i.p.). Moreover, the memory enhancing effect of DL77 (5 mg/kg, i.p.) in MK801-induced memory deficits in PAP was strongly reversed when rats were pretreated with a combination of ZOL (10 mg/kg, i.p.) and SCO (1.0 mg/kg, i.p.). Furthermore, the significant ameliorative effect of DL77 (5 mg/kg, i.p.) on MK801-induced long-term memory (LTM) impairment in NOR test was comparable to the DOZ-provided memory-enhancing effect, and was abrogated when animals were pretreated with the histamine H3R agonist R-(α)-methylhistamine (RAMH, 10 mg/kg, i.p.). However, DL77(5 mg/kg, i.p.) failed to provide procognitive effect on MK801-induced short-term memory (STM) impairment in NOR test. In addition, DL77 (5 mg/kg) did not alter anxiety levels and locomotor activity of animals naive to elevated-plus maze (EPM), demonstrating that improved performances with DL77 (5 mg/kg) in PAP or NOR are unrelated to changes in emotional responding or spontaneous locomotor activity. These results provide evidence for the potential of H3Rs for the treatment of neurodegenerative disorders related to impaired memory function, e.g. CDS.

Keywords: histamine H3 receptor, antagonist, learning, memory impairment, passive avoidance paradigm, novel object recognition

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1754 Overweight and Neurocognitive Functioning: Unraveling the Antagonistic Relationship in Adolescents

Authors: Swati Bajpai, S. P. K Jena

Abstract:

Background: There is dramatic increase in the prevalence and severity of overweight in adolescents, raising concerns about their psychosocial and cognitive consequences, thereby indicating the immediate need to understand the effects of increased weight on scholastic performance. Although the body of research is currently limited, available results have identified an inverse relationship between obesity and cognition in adolescents. Aim: to examine the association between increased Body Mass Index in adolescents and their neurocognitive functioning. Methods: A case –control study of 28 subjects in the age group of 11-17 years (14 Males and 14 females) was taken on the basis of main inclusion criteria (Body Mass Index). All of them were randomized to (experimental group: overweight) and (control group: normal weighted). A complete neurocognitive assessment was carried out using validated psychological scales namely, Color Progressive Matrices (to assess intelligence); Bender Visual Motor Gestalt Test (Perceptual motor functioning); PGI-Memory Scale for Children (memory functioning) and Malin’s Intelligence Scale Indian Children (verbal and performance ability). Results: statistical analysis of the results depicted that 57% of the experimental group lack in cognitive abilities, especially in general knowledge (99.1±12.0 vs. 102.8±6.7), working memory (91.5±8.4 vs. 93.1±8.7), concrete ability (82.3±11.5 vs. 92.6±1.7) and perceptual motor functioning (1.5±1.0 vs. 0.3±0.9) as compared to control group. Conclusion: Our investigations suggest that weight gain results, at least in part, from a neurological predisposition characterized by reduced executive function, and in turn obesity itself has a compounding negative impact on the brain. Though, larger sample is needed to make more affirmative claims.

Keywords: adolescents, body mass index, neurocognition, obesity

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1753 Etude 3D Quantum Numerical Simulation of Performance in the HEMT

Authors: A. Boursali, A. Guen-Bouazza

Abstract:

We present a simulation of a HEMT (high electron mobility transistor) structure with and without a field plate. We extract the device characteristics through the analysis of DC, AC and high frequency regimes, as shown in this paper. This work demonstrates the optimal device with a gate length of 15 nm, InAlN/GaN heterostructure and field plate structure, making it superior to modern HEMTs when compared with otherwise equivalent devices. This improves the ability to bear the burden of the current density passes in the channel. We have demonstrated an excellent current density, as high as 2.05 A/m, a peak extrinsic transconductance of 0.59S/m at VDS=2 V, and cutting frequency cutoffs of 638 GHz in the first HEMT and 463 GHz for Field plate HEMT., maximum frequency of 1.7 THz, maximum efficiency of 73%, maximum breakdown voltage of 400 V, leakage current density IFuite=1 x 10-26 A, DIBL=33.52 mV/V and an ON/OFF current density ratio higher than 1 x 1010. These values were determined through the simulation by deriving genetic and Monte Carlo algorithms that optimize the design and the future of this technology.

Keywords: HEMT, silvaco, field plate, genetic algorithm, quantum

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1752 Cognitive Linguistic Features Underlying Spelling Development in a Second Language: A Case Study of L2 Spellers in South Africa

Authors: A. Van Staden, A. Tolmie, E. Vorster

Abstract:

Research confirms the multifaceted nature of spelling development and underscores the importance of both cognitive and linguistic skills that affect sound spelling development such as working and long-term memory, phonological and orthographic awareness, mental orthographic images, semantic knowledge and morphological awareness. This has clear implications for many South African English second language spellers (L2) who attempt to become proficient spellers. Since English has an opaque orthography, with irregular spelling patterns and insufficient sound/grapheme correspondences, L2 spellers can neither rely, nor draw on the phonological awareness skills of their first language (for example Sesotho and many other African languages), to assist them to spell the majority of English words. Epistemologically, this research is informed by social constructivism. In addition the researchers also hypothesized that the principles of the Overlapping Waves Theory was an appropriate lens through which to investigate whether L2 spellers could significantly improve their spelling skills via the implementation of an alternative route to spelling development, namely the orthographic route, and more specifically via the application of visual imagery. Post-test results confirmed the results of previous research that argues for the interactive nature of different cognitive and linguistic systems such as working memory and its subsystems and long-term memory, as learners were systematically guided to store visual orthographic images of words in their long-term lexicons. Moreover, the results have shown that L2 spellers in the experimental group (n = 9) significantly outperformed L2 spellers (n = 9) in the control group whose intervention involved phonological awareness (and coding) including the teaching of spelling rules. Consequently, L2 learners in the experimental group significantly improved in all the post-test measures included in this investigation, namely the four sub-tests of short-term memory; as well as two spelling measures (i.e. diagnostic and standardized measures). Against this background, the findings of this study look promising and have shown that, within a social-constructivist learning environment, learners can be systematically guided to apply higher-order thinking processes such as visual imagery to successfully store and retrieve mental images of spelling words from their output lexicons. Moreover, results from the present study could play an important role in directing research into this under-researched aspect of L2 literacy development within the South African education context.

Keywords: English second language spellers, phonological and orthographic coding, social constructivism, visual imagery as spelling strategy

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1751 Multi-Dimensional Experience of Processing Textual and Visual Information: Case Study of Allocations to Places in the Mind’s Eye Based on Individual’s Semantic Knowledge Base

Authors: Joanna Wielochowska, Aneta Wielochowska

Abstract:

Whilst the relationship between scientific areas such as cognitive psychology, neurobiology and philosophy of mind has been emphasized in recent decades of scientific research, concepts and discoveries made in both fields overlap and complement each other in their quest for answers to similar questions. The object of the following case study is to describe, analyze and illustrate the nature and characteristics of a certain cognitive experience which appears to display features of synaesthesia, or rather high-level synaesthesia (ideasthesia). The following research has been conducted on the subject of two authors, monozygotic twins (both polysynaesthetes) experiencing involuntary associations of identical nature. Authors made attempts to identify which cognitive and conceptual dependencies may guide this experience. Operating on self-introduced nomenclature, the described phenomenon- multi-dimensional processing of textual and visual information- aims to define a relationship that involuntarily and immediately couples the content introduced by means of text or image a sensation of appearing in a certain place in the mind’s eye. More precisely: (I) defining a concept introduced by means of textual content during activity of reading or writing, or (II) defining a concept introduced by means of visual content during activity of looking at image(s) with simultaneous sensation of being allocated to a given place in the mind’s eye. A place can be then defined as a cognitive representation of a certain concept. During the activity of processing information, a person has an immediate and involuntary feel of appearing in a certain place themselves, just like a character of a story, ‘observing’ a venue or a scenery from one or more perspectives and angles. That forms a unique and unified experience, constituting a background mental landscape of text or image being looked at. We came to a conclusion that semantic allocations to a given place could be divided and classified into the categories and subcategories and are naturally linked with an individual’s semantic knowledge-base. A place can be defined as a representation one’s unique idea of a given concept that has been established in their semantic knowledge base. A multi-level structure of selectivity of places in the mind’s eye, as a reaction to a given information (one stimuli), draws comparisons to structures and patterns found in botany. Double-flowered varieties of flowers and a whorl system (arrangement) which is characteristic to components of some flower species were given as an illustrative example. A composition of petals that fan out from one single point and wrap around a stem inspired an idea that, just like in nature, in philosophy of mind there are patterns driven by the logic specific to a given phenomenon. The study intertwines terms perceived through the philosophical lens, such as definition of meaning, subjectivity of meaning, mental atmosphere of places, and others. Analysis of this rare experience aims to contribute to constantly developing theoretical framework of the philosophy of mind and influence the way human semantic knowledge base and processing given content in terms of distinguishing between information and meaning is researched.

Keywords: information and meaning, information processing, mental atmosphere of places, patterns in nature, philosophy of mind, selectivity, semantic knowledge base, senses, synaesthesia

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1750 Sceletium Tortuosum: A review on its Phytochemistry, Pharmacokinetics, Biological and Clinical Activities

Authors: Tomi Lois Olatunji, Frances Siebert, Ademola Emmanuel Adetunji, Brian Harvey, Johane Gericke, Josias Hamman, Frank Van Der Kooy

Abstract:

Ethnopharmacological relevance: Sceletium tortuosum (L.) N.E.Br, the most sought after and widely researched species in the genus Sceletium is a succulent forb endemic to South Africa. Traditionally, this medicinal plant is mainly masticated or smoked and used for the relief of toothache, abdominal pain, and as a mood-elevator, analgesic, hypnotic, anxiolytic, thirst and hunger suppressant, and for its intoxicating/euphoric effects. Sceletium tortuosum is currently of widespread scientific interest due to its clinical potential in treating anxiety and depression, relieving stress in healthy individuals, and enhancing cognitive functions. These pharmacological actions are attributed to its phytochemical constituents referred to as mesembrine-type alkaloids. Aim of the review: The aim of this review was to comprehensively summarize and critically evaluate recent research advances on the phytochemistry, pharmacokinetics, biological and clinical activities of the medicinal plant S. tortuosum. Additionally, current ongoing research and future perspectives are also discussed. Methods: All relevant scientific articles, books, MSc and Ph.D. dissertations on botany, behavioral pharmacology, traditional uses, and phytochemistry of S. tortuosum were retrieved from different databases (including Science Direct, PubMed, Google Scholar, Scopus and Web of Science). For pharmacokinetics and pharmacological effects of S. tortuosum, the focus fell on relevant publications published between 2009 and 2021. Results: Twenty-five alkaloids belonging to four structural classes viz: mesembrine, Sceletium A4, joubertiamine, and tortuosamine, have been identified from S. tortuosum, of which the mesembrine class is predominant. The crude extracts and commercially available standardized extracts of S. tortuosum have displayed a wide spectrum of biological activities (e.g. antimalarial, anti-oxidant, immunomodulatory, anti-HIV, neuroprotection, enhancement of cognitive function) in in vitro or in vivo studies. This plant has not yet been studied in a clinical population, but has potential for enhancing cognitive function, and managing anxiety and depression. Conclusion: As an important South African medicinal plant, S. tortuosum has garnered many research advances on its phytochemistry and biological activities over the last decade. These scientific studies have shown that S. tortuosum has various bioactivities. The findings have further established the link between the phytochemistry and pharmacological application, and support the traditional use of S. tortuosum in the indigenous medicine of South Africa.

Keywords: Aizoaceae, Mesembrine, Serotonin, Sceletium tortuosum, Zembrin®, psychoactive, antidepressant

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