Search results for: chemistry attitude
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1855

Search results for: chemistry attitude

865 Formulation and Evaluation of Silver Nanoparticles as Drug Carrier for Cancer Therapy

Authors: Abdelhadi Adam Salih Denei

Abstract:

Silver nanoparticles (AgNPs) have been used in cancer therapy, and the area of nanomedicine has made unheard-of strides in recent years. A thorough summary of the development and assessment of AgNPs for their possible use in the fight against cancer is the goal of this review. Targeted delivery methods have been designed to optimise therapeutic efficacy by using AgNPs' distinct physicochemical features, such as their size, shape, and surface chemistry. Firstly, the study provides an overview of the several synthesis routes—both chemical and green—that are used to create AgNPs. Natural extracts and biomolecules are used in green synthesis techniques, which are becoming more and more popular since they are biocompatible and environmentally benign. It is next described how synthesis factors affect the physicochemical properties of AgNPs, emphasising how crucial it is to modify these parameters for particular therapeutic uses. An extensive analysis is conducted on the anticancer potential of AgNPs, emphasising their capacity to trigger apoptosis, impede angiogenesis, and alter cellular signalling pathways. The analysis also investigates the potential benefits of combining AgNPs with currently used cancer treatment techniques, including radiation and chemotherapy. AgNPs' safety profile for use in clinical settings is clarified by a comprehensive evaluation of their cytotoxicity and biocompatibility.

Keywords: silver nanoparticles, cancer, nanocarrier system, targeted delivery

Procedia PDF Downloads 46
864 Risky Driving Behavior among Bus Driver in Jakarta

Authors: Ratri A. Benedictus, Felicia M. Yolanda

Abstract:

Public transport is a crucial issue for capital city in developing country, such as Jakarta. Inadequate number and low quality of public transport services resulting personal vehicles as the main option. As a result, traffic jams are getting worse in Jakarta. The low quality of public transport, particularly buses, compounded by the risk behavior of the driver. Traffic accidents involving public bus in Jakarta were often the case, even result in fatality. The purpose of this study is to get a description of risk behavior among the public bus drivers in Jakarta. 132 bus drivers become respondent of this study. Risky Driving Behavior scale of Dorn were used. Data were analyzed using descriptive statistics. 51.5% of respondents felt often showing risky behavior while on driving. The highest type of risky driving behavior is still using the unsafe bus (62%). Followed by trespass the bus line (30%), over speed (21%), violate the road signs (15%) and driving with unhealthy physical condition (4%). Results of this study suggested that high understanding of the bus drivers on their risk behaviors have not lead to the emergence of safe driving behavior. Therefore, together with technical engineering and instrumentation work intervention over this issue, psychological aspects also need to be considered, such as: risk perception, safety attitude,safety culture, locus of control and Fatalism.

Keywords: bus driver, psychological factors, public transportation, risky driving behavior

Procedia PDF Downloads 337
863 Use of Fabric Phase Sorptive Extraction with Gas Chromatography-Mass Spectrometry for the Determination of Organochlorine Pesticides in Various Aqueous and Juice Samples

Authors: Ramandeep Kaur, Ashok Kumar Malik

Abstract:

Fabric Phase Sorptive Extraction (FPSE) combined with Gas chromatography Mass Spectrometry (GCMS) has been developed for the determination of nineteen organochlorine pesticides in various aqueous samples. The method consolidates the features of sol-gel derived microextraction sorbents with rich surface chemistry of cellulose fabric substrate which could directly extract sample from complex sample matrices and incredibly improve the operation with decreased pretreatment time. Some vital parameters such as kind and volume of extraction solvent and extraction time were examinedand optimized. Calibration curves were obtained in the concentration range 0.5-500 ng/mL. Under the optimum conditions, the limits of detection (LODs) were in the range 0.033 ng/mL to 0.136 ng/mL. The relative standard deviations (RSDs) for extraction of 10 ng/mL 0f OCPs were less than 10%. The developed method has been applied for the quantification of these compounds in aqueous and fruit juice samples. The results obtained proved the present method to be rapid and feasible for the determination of organochlorine pesticides in aqueous samples.

Keywords: fabric phase sorptive extraction, gas chromatography-mass spectrometry, organochlorine pesticides, sample pretreatment

Procedia PDF Downloads 469
862 The Theory of Domination at the Bane of Conflict Resolution and Peace Building Processes in Cameroon

Authors: Nkatow Mafany Christian

Abstract:

According to UNHCR’s annual Database, humanitarian crises have globally been on the increase since the beginning of the 21st Century, especially in the Middle East and in Sub-Saharan Africa. Cameroon is one of the countries that has suffered tremendously from humanitarian challenges in recent years, especially with crises in the Far North, the East and its Two English-speaking Regions. These have been a result of failed mechanisms in conflict resolution peacebuilding by the government. The paper draws from this basic premise to argue that the failure to reach a consensus in order to curb internal conflicts has largely been due to the government’s attachment to the domineering attitude which emphasizes an imposition of peace terms by a superordinate (government) agency on the subordinate (aggrieved) entities. This has stalled peace efforts that have so far been engaged to address the dreaded armed conflicts in the North and South West Regions, leading to the persistence of the armed conflict. The paper exploits written, oral and online sources to sustain its argument. It suggests that an eclectic approach to resolving conflicts, which emphasizes open and frank dialogue as well as a review of the root causes, can go a long way not only to build trust but also to address the Anglophone-Cameroonian problems in Cameroon.

Keywords: conflict, conflict resolution, peace building, humanitarian crisis

Procedia PDF Downloads 52
861 Parents' Attitude toward Compulsory Pre-School Education in Slovakia

Authors: Sona Lorencova, Beata Hornickova

Abstract:

Compulsory pre-school education in Slovakia will be established by the Education Act for all five-year-old children from September 2021. The implementation of this law will change pre-school education in our country from optional to compulsory, and children will be able to complete this education either in institutional form school facilities or in the form of individual education at the request of the parent. The primary purpose of this change is that all children achieve pre-school education before entering primary school, thus eliminating differences between children before entering primary school. The benefits of introducing compulsory pre-school education are obvious to the professional public. However, as this fundamental change in children's education is perceived by parents who have a prime position in the upbringing and education of their children, research pays minimal attention. The aim of the study is to interpret the findings of quantitatively oriented research, which was focused on finding out the attitudes of parents to the planned introduction of compulsory preschool education in Slovakia. The data were obtained through questionnaires primarily intended for parents of preschool children. In the distributed questionnaire, the degree of agreement or disagreement with individual items could be expressed on a 5-point Likert scale. The results of the research present how perceived compulsory pre-school education is perceived by the parental public in Slovakia and what perspectives and limitations parents anticipate after its introduction.

Keywords: compulsory pre-school education, education act, childs' learning and development, kindergarten, parents' perspectives

Procedia PDF Downloads 146
860 Blogging vs Paper-and-Pencil Writing: Evidences from an Iranian Academic L2 Setting

Authors: Mehran Memari, Bita Asadi

Abstract:

Second language (L2) classrooms in academic contexts usually consist of learners with diverse L2 proficiency levels. One solution for managing such heterogeneous classes and addressing individual needs of students is to improve learner autonomy by using technological innovations such as blogging. The focus of this study is on investigating the effects of blogging on improving the quality of Iranian university students' writings. For this aim, twenty-six Iranian university students participated in the study. Students in the experimental group (n=13) were required to blog daily while the students in the control group (n=13) were asked to write a daily schedule using paper and pencil. After a 3-month period of instruction, the five last writings of the students from both groups were rated by two experienced raters. Also, students' attitudes toward the traditional method and blogging were surveyed using a questionnaire and a semi-structured interview. The research results showed evidences in favor of the students who used blogging in their writing program. Also, although students in the experimental group found blogging more demanding than the traditional method, they showed an overall positive attitude toward the use of blogging as a way of improving their writing skills. The findings of the study have implications for the incorporation of computer-assisted learning in L2 academic contexts.

Keywords: blogging, computer-assisted learning, paper and pencil, writing

Procedia PDF Downloads 382
859 The Strategy of Orbit Avoidance for Optical Remote Sensing Satellite

Authors: Dianxun Zheng, Wuxing Jing, Lin Hetong

Abstract:

Optical remote sensing satellite, always running on the Sun-synchronous orbit, equipped laser warning equipment to alert CCD camera from laser attack. There have three ways to protect the CCD camera, closing the camera cover satellite attitude maneuver and satellite orbit avoidance. In order to enhance the safety of optical remote sensing satellite in orbit, this paper explores the strategy of satellite avoidance. The avoidance strategy is expressed as the evasion of pre-determined target points in the orbital coordinates of virtual satellite. The so-called virtual satellite is a passive vehicle which superposes a satellite at the initial stage of avoidance. The target points share the consistent cycle time and the same semi-major axis with the virtual satellite, which ensures the properties of the Sun-synchronous orbit remain unchanged. Moreover, to further strengthen the avoidance capability of satellite, it can perform multi-object avoid maneuvers. On occasions of fulfilling the orbit tasks of the satellite, the orbit can be restored back to virtual satellite through orbit maneuvers. There into, the avoid maneuvers adopts pulse guidance. and the fuel consumption is also optimized. The avoidance strategy discussed in this article is applicable to avoidance for optical remote sensing satellite when encounter the laser hostile attacks.

Keywords: optical remote sensing satellite, always running on the sun-synchronous

Procedia PDF Downloads 388
858 Study of Behavior Tribological Cutting Tools Based on Coating

Authors: A. Achour L. Chekour, A. Mekroud

Abstract:

Tribology, the science of lubrication, friction and wear, plays an important role in science "crossroads" initiated by the recent developments in the industry. Its multidisciplinary nature reinforces its scientific interest. It covers all the sciences that deal with the contact between two solids loaded and relative motion. It is thus one of the many intersections more clearly established disciplines such as solid mechanics and the fluids, rheological, thermal, materials science and chemistry. As for his experimental approach, it is based on the physical and processing signals and images. The optimization of operating conditions by cutting tool must contribute significantly to the development and productivity of advanced automation of machining techniques because their implementation requires sufficient knowledge of how the process and in particular the evolution of tool wear. In addition, technological advances have developed the use of very hard materials, refractory difficult machinability, requiring highly resistant materials tools. In this study, we present the behavior wear a machining tool during the roughing operation according to the cutting parameters. The interpretation of the experimental results is based mainly on observations and analyzes of sharp edges e tool using the latest techniques: scanning electron microscopy (SEM) and optical rugosimetry laser beam.

Keywords: friction, wear, tool, cutting

Procedia PDF Downloads 321
857 Standard-with-Dialects in the Mandarin Dialect Region: Diglossia and Language Choice in Xinle

Authors: Xi Zhang

Abstract:

Much has been written about the promotion of Standard Mandarin and the negative effects it may have had on the development of non-Mandarin dialects. Less discussed, however, is the fate of northern Chinese dialects that are only marginally different from Standard Mandarin and the effect Standard Mandarin promotion may have had on such dialects. In this paper, we seek to bridge this gap by looking at language preferences in the family and the generational differences that they reflect. Specifically, we survey Mandarin dialect speakers from Xinle county in Hebei province, whose local dialect is similar but not identical to Standard Mandarin. We sample more than 160 families with pre-middle school children and ask the parents a series of questions that probe language behavior, language ability, and language attitude within the family with regard to educating the young. Our study shows that although most parents still speak the Xinle dialect, Standard Mandarin has become the language taught to the majority of children. We also show that only one-third of parents choose to preserve elements of Xinle dialect in the language they teach to their children. We analyze the possible factors (e.g., subjective, geographical, social, and external) that influence language choice and show how these factors collectively contribute to the current state of family language choice for educational purposes. Finally, based on our findings, we offer recommendations for coordinating the promotion of Standard Mandarin and dialect preservation in similar Mandarin-speaking regions.

Keywords: Diglossia, language planning, Mandarin, standard-with-dialects

Procedia PDF Downloads 58
856 Teachers' Preferences on the Issue of Segregation of Gifted Pupils in Czech Educational System

Authors: I. Kočvarová, E. Machů, N. Bártlová

Abstract:

The issue of inclusion - segregation in the current Czech educational system is highly actual due to changes in legislation. It applies primarily to pupils with special educational needs, but it should also apply to pupils with giftedness. The paper presents chosen results of an exploratory survey that was carried out on a convenience sample of 1101 Czech teachers working in lower secondary education (ISCED2). The rate of teachers´ agreement with segregation of gifted pupils in the education system was monitored during this investigation. A validated questionnaire of our own design was used for the purpose of this investigation. The results were compared across groups of teachers in terms of selected variables. Results show that 36,3 % of teachers incline to segregation (rather than inclusion) of gifted pupils. Teachers who are not educated in this field and have no experience in teaching gifted pupils tend to support their segregation more in comparison with other teachers. Teachers of specialized schools for gifted pupils paradoxically agree with segregation to a slightly lesser extent than teachers from traditional schools, but they also manifest the most hesitant attitude in this issue. Preferences for segregation of gifted pupils are not related to attitudes toward gifted pupils or teachers' self-evaluation in terms of care for the gifted. Investigation indicates that the issue of education of gifted children and their inclusion in the educational system needs more space within the further education of teachers.

Keywords: educational system, evaluation, gifted pupil, inclusion, segregation, teacher

Procedia PDF Downloads 312
855 Development of Antibacterial Surface Based on Bio-Inspired Hierarchical Surface

Authors: M.Ayazi, N. Golshan Ebrahimi

Abstract:

The development of antibacterial surface has devoted extensive researches and important field due to the growing antimicrobial resistance strains. The superhydrophobic surface has raised attention because of reducing bacteria adhesion in the absence of antibiotic agents. Evaluating the current development antibacterial surface has to be investigating to consider the potential of applying superhydrophobic surface to reduce bacterial adhesion or role of patterned surfaces on it. In this study, we present different samples with bio-inspired hierarchical and microstructures to consider their ability in reducing bacterial adhesion. The structures have inspired from rice-like pattern and lotus-leaf that developed on the polydimethylsiloxane (PDMS) and polypropylene (PP). The results of the attachment behaviors have considered on two bacteria strains of gram-negative Escherichia coli (E. coli) bacteria and gram-positive Staphylococcus aureus (S. aureus). The reduction of bacteria adhesion on these roughness surfaces demonstrated the effectiveness of rinsing ability on removing bacterial cells on structured plastic surfaces. Results have also offered the important role of bacterial species, material chemistry and hierarchical structure to prevent bacterial adhesion.

Keywords: hierarchical structure, self-cleaning, lotus-effect, bactericidal

Procedia PDF Downloads 128
854 In Silico Design of Organometallic Complexes as Potential Antibacterial Agents

Authors: Sanja O. Podunavac-Kuzmanović, Strahinja Z. Kovačević, Lidija R. Jevrić, Stela Jokić

Abstract:

The complexes of transition metals with various organic ligands have been extensively studied as models of some important pharmaceutical molecules. It was found that biological properties of different substituted organic molecules are improved when they are complexed by different metals. Therefore, it is of great importance for the development of coordination chemistry to explore the assembly of functional organic ligands with metal ion and to investigate the relationship between the structure and property. In the present work, we have bioassayed the antibacterial potency of benzimidazoles and their metal salts (Cu or Zn) against yeast Sarcina lutea. In order to validate our in vitro study, we performed in silico studies using molecular docking software. The investigated compounds and their metal complexes (Cu, Zn) showed good to moderate inhibitory activity against Sarcina lutea. In silico docking studies of the synthesized compounds suggested that complexed benzimidazoles have a greater binding affinity and improved antibacterial activity in comparison with non-complexed ligands. These results are part of the CMST COST Action No. 1105 "Functional metal complexes that bind to biomolecules".

Keywords: organometallic complexes, benzimidazoles, chemometric design, Sarcina lutea

Procedia PDF Downloads 328
853 Francophone University Students' Attitudes Towards English Accents in Cameroon

Authors: Eric Agrie Ambele

Abstract:

The norms and models for learning pronunciation in relation to the teaching and learning of English pronunciation are key issues nowadays in English Language Teaching in ESL contexts. This paper discusses these issues based on a study on the attitudes of some Francophone university students in Cameroon towards three English accents spoken in Cameroon: Cameroon Francophone English (CamFE), Cameroon English (CamE), and Hyperlectal Cameroon English (near standard British English). With the desire to know more about the treatment that these English accents receive among these students, an aspect that had hitherto received little attention in the literature, a language attitude questionnaire, and the matched-guise technique was used to investigate this phenomenon. Two methods of data analysis were employed: (1) the percentage count procedure, and (2) the semantic differential scale. The findings reveal that the participants’ attitudes towards the selected accents vary in degree. Though Hyperlectal CamE emerged first, CamE second and CamFE third, no accent, on average, received a negative evaluation. It can be deduced from this findings that, first, CamE is gaining more and more recognition and can stand as an autonomous accent; second, that the participants all rated Hyperlectal CamE higher than CamE implies that they would be less motivated in a context where CamE is the learning model. By implication, in the teaching of English pronunciation to francophone learners learning English in Cameroon, Hyperlectal Cameroon English should be the model.

Keywords: teaching pronunciation, English accents, Francophone learners, attitudes

Procedia PDF Downloads 180
852 English Syllabus in the Iranian Education System

Authors: Shaghayegh Mirshekari, Atiyeh Ghorbani

Abstract:

EThe Iranian system of education has been politically influenced by the thoughts of the governing religious party. It has brought many religious books into the educational system from grade one up to graduation from high school, and therefore, teaching English as a non-Islamic language has been put aside the system, focusing on the Islamic language of Arabic. Teaching English has been widely talked about in international academia, but the Iranian educational system has not brought in any of its outcomes due to the general policy of keeping people away from international Western thoughts. Because of the increasing interest among Iranians in learning English, this language is being taught and studied in public and private schools, commercial and adult schools, language institutes, colleges, universities, and numerous homes throughout the country. Methods and techniques of teaching English, the attitude of the teachers and learners towards the language, and the availability of textbooks and other language materials are quite different in any one of the different institutions. This paper has evaluated the outcome of the Iranian educational system in teaching English in terms of their methods of teaching, as well as the policies regarding the educational system. The results show that not only has there been no progress in the system in terms of teaching English, rather there is backwardness in this regard due to the political policy of preventing people from learning English. Therefore, we see the majority of the youth not speaking English properly at the age where they need to enter the international arena.

Keywords: English, public school, language, Iran, teaching

Procedia PDF Downloads 50
851 Smelling Our Way through Names: Understanding the Potential of Floral Volatiles as Taxonomic Traits in the Fragrant Ginger Genus Hedychium

Authors: Anupama Sekhar, Preeti Saryan, Vinita Gowda

Abstract:

Plants, due to their sedentary lifestyle, have evolved mechanisms to synthesize a huge diversity of complex, specialized chemical metabolites, a majority of them being volatile organic compounds (VOCs). These VOCs are heavily involved in their biotic and abiotic interactions. Since chemical composition could be under the same selection processes as other morphological characters, we test if VOCs can be used to taxonomically distinguish species in the well-studied, fragrant ginger genus -Hedychium (Zingiberaceae). We propose that variations in the volatile profiles are suggestive of adaptation to divergent environments, and their presence could be explained by either phylogenetic conservatism or ecological factors. In this study, we investigate the volatile chemistry within Hedychium, which is endemic to Asian palaeotropics. We used an unsupervised clustering approach which clearly distinguished most taxa, and we used ancestral state reconstruction to estimate phylogenetic signals and chemical trait evolution in the genus. We propose that taxonomically, the chemical composition could aid in species identification, especially in species complexes where taxa are not morphologically distinguishable, and extensive, targeted chemical libraries will help in this effort.

Keywords: chemotaxonomy, dynamic headspace sampling, floral fragrance, floral volatile evolution, gingers, Hedychium

Procedia PDF Downloads 79
850 Research on the Online Learning Activities Design and Students’ Experience Based on APT Model

Authors: Wang Yanli, Cheng Yun, Yang Jiarui

Abstract:

Due to the separation of teachers and students, online teaching during the COVID-19 epidemic was faced with many problems, such as low enthusiasm of students, distraction, low learning atmosphere, and insufficient interaction between teachers and students. The essay designed the elaborate online learning activities of the course 'Research Methods of Educational Science' based on the APT model from three aspects of multiple assessment methods, a variety of teaching methods, and online learning environment and technology. Student's online learning experience was examined from the perception of online course, the perception of the online learning environment, and satisfaction after the course’s implementation. The research results showed that students have a positive overall evaluation of online courses, a high degree of engagement in learning, positive acceptance of online learning, and high satisfaction with it, but students hold a relatively neutral attitude toward online learning. And some dimensions in online learning experience were found to have positive influence on students' satisfaction with online learning. We suggest making the good design of online courses, selecting proper learning platforms, and conducting blended learning to improve students’ learning experience. This study has both theoretical and practical significance for the design, implementation, effect feedback, and sustainable development of online teaching in the post-epidemic era.

Keywords: APT model, online learning, online learning activities, learning experience

Procedia PDF Downloads 118
849 Mimicking of Various ECM Tangible Cues for the Manipulation of Hepatocellular Behaviours

Authors: S. A. Abdellatef, A. Taniguchi, Namiki, Tsukuba, Ibaraki

Abstract:

The alterations in the physicochemical characteristics of bio-materials are renowned for their impact in cellular behaviors. Surface chemistry and substratum topography are separately considered as mutable characteristics with deep impact on the overall cell behaviors. In our recent work, we examined the manipulation of the physical cues on hepatic cellular behaviors. We have proven that the geometrical or dimensional characteristics of nano features are essential for the optimum hepatocellular functions. While here, the collective impact of both physical and chemical cues on hepatocellular behaviors was investigated. On which RGD peptide was immobilized on a TiO2 nano pattern that imitates the hierarchically extend collagen nano fibrillar structures. The hepatocytes morphological and functional changes induced by simultaneously combining the diversified cues were investigated. TiO2 substrates that integrate nano topography with the adhesive peptide motif (RGD) had showed an increase in the hepatocellular functionality to the maximum extent. While a significant enhancement in expression of these liver specific markers on RGD coated surfaces were observed compared to uncoated substrates regardless of topography. Consequently in depth understanding of the relationship between various kind of cues and hepatocytes behaviors would be a paving step in the application of tissue engineering and bio reactor technology.

Keywords: biomaterial, tiO2, hepG2, RGD

Procedia PDF Downloads 384
848 Building a Performance Outline for Health Care Workers at Teaching Hospitals, Nigeria: The Role of Different Leadership Styles

Authors: Osuagwu Justine Ugochukwu

Abstract:

Investigating the effects of transformational and transactional leadership styles on the performance of healthcare employees at the University Teaching Hospital (UNTH) in Enugu, Nigeria, was the goal of the research. The respondents were asked to fill out a structured questionnaire. The respondents were chosen using a straightforward random sampling technique and consisted of 370 health workers at the hospital. The result of the analysis revealed that transactional and transformational leadership style has a positive while ambidextrous leadership has a negative effect on healthcare workers' performance in UNTH, Enugu. Therefore, the management of public hospitals that have the capacity to change their top management approach to leadership styles will gain substantial support from their employees’ thereby increasing organizational commitment and performance among health workers. This will have remarkable social implications, one of which is a change in the work culture and attitude of medical personnel from the seemingly anti-community of patients to friendly engagement and treatment of patients leading to a harmonious coexistence among these individuals in society. Investigating ambidextrous leadership and the use of nonparametric analysis is unique and has brought brand-new knowledge to leadership literature.

Keywords: workers performance, transformational leadership, transactional leadership, governance quality, ambidextrous leadership

Procedia PDF Downloads 70
847 Tetra Butyl Ammonium Cyanate Mediated Selective Synthesis of Sulfonyltriuret and Their Investigation towards Trypsin Protease Modulation

Authors: Amarjyoti Das Mahapatra, Umesh Kumar, Bhaskar Datta

Abstract:

A pseudo peptide can mimic the biological or structural properties of natural peptides. They have become an increasing attention in medicinal chemistry because of their interesting advantages like more bioavailability and less biodegradation than compare to the physiologically active native peptides which increase their therapeutic applications. Many biologically active compounds contain urea as functional groups, and they have improved pharmacokinetic properties because of their bioavailability and metabolic stability. Recently we have reported a single-step synthesis of sulfonyl urea and sulfonyltriuret from sulfonyl chloride and sodium cyanate. But the yield of sulfonyltriuret was less around 40-60% because of the formation of other products like sulfonamide and sulfonylureas. In the present work, we mainly focused on the selective synthesis of sulfonyltriuret using tetrabutylammonium cyanate and sulfonyl chloride. More precisely, we are interested in the controlled synthesis of oligomeric urea mainly sulfonyltriuret as a new class of pseudo peptide and their application as protease modulators. The distinctive architecture of these molecules in the form of their pseudo-peptide backbone offers promise as a potential pharmacophore. The synthesized molecules have been screened on trypsin enzyme, and we observed that these molecules are the efficient modulator of trypsin enzyme.

Keywords: pseudo peptide, pharmacophore, sulfonyltriuret, trypsin

Procedia PDF Downloads 152
846 Effect of Wettability Alteration in Low Salt Water Injection Modeling

Authors: H. Vahdani

Abstract:

By the adsorption of polar compounds and/or the deposition of organic material, the wettability of originally water-wet reservoir rock can be altered. The degree of alteration is determined by the interaction of the oil constituents, the mineral surface, and the brine chemistry. Recently improving oil recovery by tuning wettability alteration is believed as a new recovery method. Various researchers have demonstrated that low salt water injection has a significant impact on oil recovery. It has been shown, for instance, that additional oil can be produced from reservoir rock by managing the injection water. Large wettability sensitivity has been observed, indicating that the oil/water capillary pressure profiles play a major role during low saline water injection simulation. Although the exact physics on how this alteration occurs is still a research topic; however, it has been reported that some of its effect can be captured by a relative permeability shift from an oil-wet system to a water-wet system. Modeling of low salt water injection mainly is based on the theory of wettability alteration and is hence strongly dependent on the wettability of the reservoir. In this article, combination of different wettabilities has been simulated and it is observed that the highest recoveries were from the cases were the reservoir initially was water-wet, and the lowest recoveries was from the cases were the reservoir initially was considered oil-wet. However for the cases where the reservoir initially was oil-wet, the effect of low-salinity waterflooding was the largest.

Keywords: low salt water injection, wettability alteration, modelling, relative permeability

Procedia PDF Downloads 480
845 Traditional versus New Media: Creating Awareness on Environment Protection in Pakistan

Authors: Hafsah Javed

Abstract:

Environment protection is a major issue grabbing widespread attention of policymakers, both, locally and globally. Pakistan is among the countries most affected by global climate changes; media, besides governments, have a prime responsibility to create awareness among people about its hazards, and managing strategies. Advances in Information Communication Technologies have eased people's access to information and created an interactive space to discuss environment related issues and influence the policy decisions on the issue. This study, therefore, aims to examine, from the perspective of the audience, the contribution of Pakistani traditional and social media in creating awareness about Environment Protection and its implications. The objectives are achieved through quantitative survey method. Young university students are selected as ‘audience’ for the study. The findings show lack of awareness among people regarding environment protection. Neither traditional media outlets like radio, TV and newspapers prioritize the issue on their agenda, nor audience pull information about the issue from social media. A stark indifference and non-serious attitude is being exercised towards the issue from two quarters. People do not know much about local and international laws on environment; media are used more than a source of entertainment than awareness. The study implicates that there is an exigency to launch a nationwide awareness campaign on the issue, and for that media need to be on the driving seat.

Keywords: awareness, climate change, environment protection, new media, role of media, youngsters

Procedia PDF Downloads 130
844 Chemical Modification of Jute Fibers with Oxidative Agents for Usability as Reinforcement in Polymeric Composites

Authors: Yasemin Seki, Aysun Akşit

Abstract:

The goal of this research is to modify the surface characterization of jute yarns with different chemical agents to improve the compatibility with a non-polar polymer, polypropylene, when used as reinforcement. A literature review provided no knowledge on surface treatment of jute fibers with sodium perborate trihydrate. This study also aims to compare the efficiency of sodium perborate trihydrate on jute fiber treatment with other commonly used chemical agents. Accordingly, jute yarns were treated with 0.02% potassium dichromate (PD), potassium permanganate (PM) and sodium perborate trihydrate (SP) aqueous solutions in order to enhance interfacial compatibility with polypropylene in this study. The effect of treatments on surface topography, surface chemistry and interfacial shear strength of jute yarns with polypropylene were investigated. XPS results revealed that surface treatments enhanced surface hydrophobicity by increasing C/O ratios of fiber surface. Surface roughness values increased with the treatments. The highest interfacial adhesion with polypropylene was achieved after SP treatment by providing the highest surface roughness values and hydrophobic character of jute fiber.

Keywords: jute, chemical modification, sodium perborate, polypropylene

Procedia PDF Downloads 494
843 Synthesis, Electrochemical and Fluorimetric Analysis of Caffeic Cinnamic and Acid-Conjugated Hemorphine Derivatives Designed as Potential Anticonvulsant Agents

Authors: Jana Tchekalarova, Stela Georgieva, Petia Peneva, Petar Todorov

Abstract:

In the present study, a series of bioconjugates of N-modified hemorphine analogs containing second pharmacophore cinnamic acids (CA) or caffeic acid (KA) were synthesized by a traditional solid-phase Fmoc chemistry method for peptide synthesis. Electrochemical and fluorometric analysis and in vivo anticonvulsant activity in mice were conducted on the compounds. The three CA (H4-CA, H5-CA, and H7-CA) and three KA (H4-KA, H5-KA, and H7-KA)-conjugated hemorphine derivatives showed dose-dependent anticonvulsant activity in the maximal electroshock test (MES) in mice. The KA-conjugated H5-KA derivate was the only compound that suppressed clonic seizures at the lowest dose of 0.5 µg/mouse in the scPTZ test. The activity against the psychomotor seizures in the 6-Hz test was detected only for the H4-CA (0.5 µg) and H4-KA (0.5 µg and 1 µg), respectively. The peptide derivates did not exhibit neurotoxicity in the rotarod test. Our findings suggest that conjugated CA and KA hemorphine peptides can be used as a background for developing hemorphin-related analogs with anticonvulsant activity. Acknowledgments: This study is funded by the European Union-NextGenerationEU, through the National Recovery and Resilience Plan of the Republic of Bulgaria, project № BG-RRP-2.004-0002, "BiOrgaMCT".

Keywords: hemorphins, SPSS, caffeic/cinnamic acid, anticonvulsant activity, electrochemistry, fluorimetry

Procedia PDF Downloads 141
842 Empowering Persons with Disabilities in Indonesia: Translating the Disability Law into Practice

Authors: Marthella Rivera Roidatua

Abstract:

Since the release of Convention on the Rights of Persons with Disabilities in 2006, disability became a mainstreamed global issue. Many developed countries have shown the continuous effort to improve their disability employment policy, for example, the US and the UK with their integrated support system through disability benefits. Relative little recent research on developing country is available. Surprisingly, Indonesia, just enacted the Law No.8/2016 on Disability that bravely highlighted on integrating disabled people into the workforce. It shows a positive progress shifting traditional perspective to what Tom Shakespeare’s concept of a social model of disability. But, the main question is how can this law support the disabled people to access and maintain paid work. Thus, besides the earlier literature reviews, interviews with leading sectors, Ministry of Social Affairs and Ministry of Manpower, was conducted to examine government’s attitude towards the disabled worker. Insights from two local social enterprises on disability were also engaged in building better perspective. The various source of data was triangulated then analysed with a thematic approach. Results were encouraging the Indonesian government to have a better collaboration with other impactful local organisations in promoting the disability employment. In the end, this paper also recommends the government to make a reasonable adjustment and practical guideline for companies in hiring disabled.

Keywords: disability, employment, policy, Indonesia, collaboration, guidelines

Procedia PDF Downloads 224
841 Separation of Lanthanides Ions from Mineral Waste with Functionalized Pillar[5]Arenes: Synthesis, Physicochemical Characterization and Molecular Dynamics Studies

Authors: Ariesny Vera, Rodrigo Montecinos

Abstract:

The rare-earth elements (REEs) or rare-earth metals (REMs), correspond to seventeen chemical elements composed by the fifteen lanthanoids, as well as scandium and yttrium. Lanthanoids corresponds to lanthanum and the f-block elements, from cerium to lutetium. Scandium and yttrium are considered rare-earth elements because they have ionic radii similar to the lighter f-block elements. These elements were called rare earths because they are simply more difficult to extract and separate individually than the most metals and, generally, they do not accumulate in minerals, they are rarely found in easily mined ores and are often unfavorably distributed in common ores/minerals. REEs show unique chemical and physical properties, in comparison to the other metals in the periodic table. Nowadays, these physicochemical properties are utilized in a wide range of synthetic, catalytic, electronic, medicinal, and military applications. Because of their applications, the global demand for rare earth metals is becoming progressively more important in the transition to a self-sustaining society and greener economy. However, due to the difficult separation between lanthanoid ions, the high cost and pollution of these processes, the scientists search the development of a method that combines selectivity and quantitative separation of lanthanoids from the leaching liquor, while being more economical and environmentally friendly processes. This motivation has favored the design and development of more efficient and environmentally friendly cation extractors with the incorporation of compounds as ionic liquids, membrane inclusion polymers (PIM) and supramolecular systems. Supramolecular chemistry focuses on the development of host-guest systems, in which a host molecule can recognize and bind a certain guest molecule or ion. Normally, the formation of a host-guest complex involves non-covalent interactions Additionally, host-guest interactions can be influenced among others effects by the structural nature of host and guests. The different macrocyclic hosts for lanthanoid species that have been studied are crown ethers, cyclodextrins, cucurbituryls, calixarenes and pillararenes.Among all the factors that can influence and affect lanthanoid (III) coordination, perhaps the most basic of them is the systematic control using macrocyclic substituents that promote a selective coordination. In this sense, macrocycles pillar[n]arenes (P[n]As) present a relatively easy functionalization and they have more π-rich cavity than other host molecules. This gives to P[n]As a negative electrostatic potential in the cavity which would be responsible for the selectivity of these compounds towards cations. Furthermore, the cavity size, the linker, and the functional groups of the polar headgroups could be modified in order to control the association of lanthanoid cations. In this sense, different P[n]As systems, specifically derivatives of the pentamer P[5]A functionalized with amide, amine, phosphate and sulfate derivatives, have been designed in terms of experimental synthesis and molecular dynamics, and the interaction between these P[5]As and some lanthanoid ions such as La³+, Eu³+ and Lu³+ has been studied by physicochemical characterization by 1H-NMR, ITC and fluorescence in the case of Eu³+ systems. The molecular dynamics study of these systems was developed in hexane as solvent, also taking into account the lanthanoid ions mentioned above, and the respective comparison studies between the different ions.

Keywords: lanthanoids, macrocycles, pillar[n]arenes, rare-earth metal extraction, supramolecular chemistry, supramolecular complexes.

Procedia PDF Downloads 60
840 Teachers’ Continuance Intention Towards Using Madrasati Platform: A Conceptual Framework

Authors: Fiasal Assiri, Joanna Wincenciak, David Morrison-Love

Abstract:

With the rapid spread of the COVID-19 pandemic, the Saudi government suspended students from going to school to combat the outbreak. As e-learning was not applied at all in schools, online teaching and learning have been revived in Saudi Arabia by providing a new platform called ‘Madrasati.’ Several studies have used the Decomposed Theory of Planned Behaviour (DTPB)to examineindividuals’ intention behavior in many fields. However, there is a lack of studies investigating the determinants of teachers’ continued intention touseMadrasati platform. The purpose of this paper is to present a conceptual model in light of DTPB. To enhance the predictability of the model, the study incorporates other variables, including learning content quality and interactivity as sub-factors under the perceived usefulness, students and government influences under the subjective norms, and technical support and prior e-learning experience under the perceived behavioral control. The model will be further validated using a mixed methods approach. Such findings would help administrators and stakeholders to understand teachers’ needs and develop new methods that might encourage teachers to continue using Madrasati effectively in their teaching.

Keywords: madrasati, decomposed theory of planned behaviour, continuance intention, attitude, subjective norms, perceived behavioural control

Procedia PDF Downloads 89
839 Perceptions and Attitudes toward Pain in Patients with Chronic Low-Back Pain

Authors: Naomi Sato, Tomonori Sato, Kenji Masui, Rob Stanborough

Abstract:

To date, there are few studies on the subjective experiences of patients with chronic low-back pain (CLBP). The purpose of this study was to gain a better understanding of CLBP patients’ perceptions and attitudes regarding pain. Individual, semi-constructed interviews were conducted with 7 Japanese and 10 Americans who had been diagnosed with CLBP. The interviews were transcribed verbatim and analyzed based on a content analysis approach. The study proposal was approved by the Institutional Review Board of the first author’s affiliate university. All participants provided written consent. Participants’ ages ranged from 48 to 82. Five main categories were emerged, namely, 'There are no reasons for long-term chronic pain,' 'Just will not worsen,' 'Have something to help me cope,' 'Pain restricts my life,' and 'Have something to relieve me.' Participants lived with CLBP, which could sometimes be avoided as a result of the coping strategies that they employed, and due to which they sometimes felt helpless, despite their efforts. As a result, they had mixed feelings, which included resignation, resoluteness, and optimism. However, their perceptions and attitudes toward pain seemed to differ based on their backgrounds, including biological, social, religious, and cultural status. There is a need for the development of a scale in future studies, to enable quantitative measurement of individuals’ perceptions of and attitudes toward pain. There is also a need for an investigation of factors influencing perceptions and attitudes toward pain.

Keywords: attitude, chronic low-back pain, perception, qualitative study

Procedia PDF Downloads 236
838 A Contested Territory in a Sacralized Landscape: The Fight of the Gich Community over Semien Mountains National Park

Authors: Marshet Girmay

Abstract:

Local community involvement is widely considered vital for the sustainability of heritage management. Yet, it is often the case that heritage-related projects lag behind in community involvement. In the Semien Mountains the creation, first, and expansion, later, of the National Park has led to several conflicts with the local communities that for centuries have inhabited the area. Local communities have only been passive actors in the plans to expand the Park set up by UNESCO and by local decision makers. This paper investigates the causes that led the Gich community, one of the communities affected by the Park’s expansion, to refuse the resettlement plan offered by the authorities. Qualitative research methods were employed, including document analysis, community conference and interview of informants. The paper shows that although the local community of Gich was highly attached to the Park’s heritage assets, their level of involvement in the heritage management was very low due to shortcomings in the design and implementation of official policies. Therefore, their attitude towards the Park’s managers has been until the present one of mistrust and opposition. The paper recommends to policy-makers a series of measures more sensitive towards local communities, such as that the development agencies act as true communication facilitators and regional authorities nurture sincere relationships with the locals.

Keywords: Gich, heritage management, local communities, Semen Mountains, sustainability, UNESCO, world heritage site

Procedia PDF Downloads 322
837 Benzoxaboralone: A Boronic Acid with High Oxidative Stability and Utility in Biological Contexts

Authors: Brian J. Graham, Ronald T. Raines

Abstract:

The presence of a nearly vacant p orbital on boron endows boronic acids with unique abilities as a catalyst and ligand. An organocatalytic process has been developed for the conversion of biomass-derived sugars to 5-hydroxymethylfurfural, which is a platform chemical. Specifically, 2-carboxyphenylboronic acid (2-CPBA) has been shown to be an optimal catalyst for this process, promoting the desired transformation in the absence of metals. The attributes of 2-CPBA as a catalyst led to additional investigations of its structure and reactivity. 2-CPBA was found to exist as a cyclized benzoxaborolone adduct rather than a free carboxylic acid. This cyclization has profound consequences for the oxidative stability of the boronic acid. Stereoelectronic effects within the oxaborolone ring destabilize the oxidation transition state by reducing electron donation from the cyclic oxygen to the developing p orbital on boron. That leads to a 10,000-fold increase in oxidative stability while maintaining the normal reactivity of boronic acids toward diols (e.g., carbohydrates) and nucleophiles in proteins while also presenting numerous hydrogen-bond accepting and donating groups. Thus, benzoxaborolones are useful in catalysis, chemical biology, medicinal chemistry, and allied fields.

Keywords: bioisosteres, boronic acid, catalysis, oxidative stability, pharmacophore, stereoelectronic effects

Procedia PDF Downloads 176
836 An Optimal Approach for Full-Detailed Friction Model Identification of Reaction Wheel

Authors: Ghasem Sharifi, Hamed Shahmohamadi Ousaloo, Milad Azimi, Mehran Mirshams

Abstract:

The ever-increasing use of satellites demands a search for increasingly accurate and reliable pointing systems. Reaction wheels are rotating devices used commonly for the attitude control of the spacecraft since provide a wide range of torque magnitude and high reliability. The numerical modeling of this device can significantly enhance the accuracy of the satellite control in space. Modeling the wheel rotation in the presence of the various frictions is one of the critical parts of this approach. This paper presents a Dynamic Model Control of a Reaction Wheel (DMCR) in the current control mode. In current-mode, the required current is delivered to the coils in order to achieve the desired torque. During this research, all the friction parameters as viscous and coulomb, motor coefficient, resistance and voltage constant are identified. In order to model identification of a reaction wheel, numerous varying current commands apply on the particular wheel to verify the estimated model. All the parameters of DMCR are identified by classical Levenberg-Marquardt (CLM) optimization method. The experimental results demonstrate that the developed model has an appropriate precise and can be used in the satellite control simulation.

Keywords: experimental modeling, friction parameters, model identification, reaction wheel

Procedia PDF Downloads 221