Search results for: conducting polymer
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2454

Search results for: conducting polymer

684 Marine Litter and Microplastic Pollution in Mangrove Sediments in The Sea of Oman

Authors: Muna Al-Tarshi, Dobretsov Sergey, Wenresti Gallardo

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Marine litter pollution is a global concern that has wide-ranging ecological, societal, and economic implications, along with potential health risks for humans. In Oman, inadequate solid waste management has led to the accumulation of litter in mangrove ecosystems. However, there is a dearth of information on marine litter and microplastic pollution in Omani mangroves, impeding the formulation of effective mitigation strategies. To address this knowledge gap, we conducted a comprehensive assessment of marine litter and microplastics in mangrove sediments in the Sea of Oman. Our study measured the average abundance of marine litter, which ranged from 0.83±1.03 to 19.42±8.52 items/m2. Notably, plastics constituted the majority of litter, accounting for 73-96% of all items, with soft plastics being the most prevalent. Furthermore, we investigated microplastic concentrations in the sediments, finding levels ranging from 6 to 256 pieces /kg. Among the studied areas, afforested mangroves in Al-Sawadi exhibited the highest average abundance of microplastics (27.52±5.32 pieces/ kg), while the Marine Protected Area Al Qurum had the lowest average abundance (0.60±1.12 pieces /kg). These findings significantly contribute to our understanding of marine litter and microplastic pollution in Omani mangroves. They provide valuable baseline data for future monitoring initiatives and the development of targeted management strategies. Urgent action is needed to implement effective waste management practices and interventions to protect the ecological integrity of mangrove ecosystems in Oman and mitigate the risks associated with marine litter and microplastics.

Keywords: microplastics, anthropogenic marine litter, ftir, polymer, khawr, mangrove, sediment

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683 Molecular Engineering of High-Performance Nanofiltration Membranes from Intrinsically Microporous Poly (Ether-Ether-Ketone)

Authors: Mahmoud A. Abdulhamid

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Poly(ether-ether-ketone) (PEEK) has received increased attention due to its outstanding performance in different membrane applications including gas and liquid separation. However, it suffers from a semi-crystalline morphology, bad solubility and low porosity. To fabricate membranes from PEEK, the usage of harsh acid such as sulfuric acid is essential, regardless its hazardous properties. In this work, we report the molecular design of poly(ether-ether-ketones) (iPEEKs) with intrinsic porosity character, by incorporating kinked units into PEEK backbone such as spirobisindane, Tröger's base, and triptycene. The porous polymers were used to fabricate stable membranes for organic solvent nanofiltration application. To better understand the mechanism, we conducted molecular dynamics simulations to evaluate the possible interactions between the polymers and the solvents. Notable enhancement in separation performance was observed confirming the importance of molecular engineering of high-performance polymers. The iPEEKs demonstrated good solubility in polar aprotic solvents, a high surface area of 205–250 m² g⁻¹, and excellent thermal stability. Mechanically flexible nanofiltration membranes were prepared from N-methyl-2-pyrrolidone dope solution at iPEEK concentrations of 19–35 wt%. The molecular weight cutoff of the membranes was fine-tuned in the range of 450–845 g mol⁻¹ displaying 2–6 fold higher permeance (3.57–11.09 L m⁻² h⁻¹ bar⁻¹) than previous reports. The long-term stabilities were demonstrated by a 7 day continuous cross-flow filtration.

Keywords: molecular engineering, polymer synthesis, membrane fabrication, liquid separation

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682 Research Trends in Using Virtual Reality for the Analysis and Treatment of Lower-Limb Musculoskeletal Injury of Athletes: A Literature Review

Authors: Hannah K. M. Tang, Muhammad Ateeq, Mark J. Lake, Badr Abdullah, Frederic A. Bezombes

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There is little research applying virtual reality (VR) to the treatment of musculoskeletal injury in athletes. This is despite their prevalence, and the implications for physical and psychological health. Nevertheless, developments of wireless VR headsets better facilitate dynamic movement in VR environments (VREs), and more research is expected in this emerging field. This systematic review identified publications that used VR interventions for the analysis or treatment of lower-limb musculoskeletal injury of athletes. It established a search protocol, and through narrative discussion, identified existing trends. Database searches encompassed four term sets: 1) VR systems; 2) musculoskeletal injuries; 3) sporting population; 4) movement outcome analysis. Overall, a total of 126 publications were identified through database searching, and twelve were included in the final analysis and discussion. Many of the studies were pilot and proof of concept work. Seven of the twelve publications were observational studies. However, this may provide preliminary data from which clinical trials will branch. If specified, the focus of the literature was very narrow, with very similar population demographics and injuries. The trends in the literature findings emphasised the role of VR and attentional focus, the strategic manipulation of movement outcomes, and the transfer of skill to the real-world. Causal inferences may have been undermined by flaws, as most studies were limited by the practicality of conducting a two-factor clinical-VR-based study. In conclusion, by assessing the exploratory studies, and combining this with the use of numerous developments, techniques, and tools, a novel application could be established to utilise VR with dynamic movement, for the effective treatment of specific musculoskeletal injuries of athletes.

Keywords: athletes, lower-limb musculoskeletal injury, rehabilitation, return-to-sport, virtual reality

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681 Land Suitability Assessment for Vineyards in Afghanistan Based on Physical and Socio-Economic Criteria

Authors: Sara Tokhi Arab, Tariq Salari, Ryozo Noguchi, Tofael Ahamed

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Land suitability analysis is essential for table grape cultivation in order to increase its production and productivity under the dry condition of Afghanistan. In this context, the main aim of this paper was to determine the suitable locations for vineyards based on satellite remote sensing and GIS (geographical information system) in Kabul Province of Afghanistan. The Landsat8 OLI (operational land imager) and thermal infrared sensor (TIRS) and shuttle radar topography mission digital elevation model (SRTM DEM) images were processed to obtain the normalized difference vegetation index (NDVI), normalized difference moisture index (NDMI), land surface temperature (LST), and topographic criteria (elevation, aspect, and slope). Moreover, Jaxa rainfall (mm per hour), soil properties information are also used for the physical suitability of vineyards. Besides, socio-economic criteria were collected through field surveys from Kabul Province in order to develop the socio-economic suitability map. Finally, the suitable classes were determined using weighted overly based on a reclassification of each criterion based on AHP (Analytical Hierarchy Process) weights. The results indicated that only 11.1% of areas were highly suitable, 24.8% were moderately suitable, 35.7% were marginally suitable and 28.4% were not physically suitable for grapes production. However, 15.7% were highly suitable, 17.6% were moderately suitable, 28.4% were marginally suitable and 38.3% were not socio-economically suitable for table grapes production in Kabul Province. This research could help decision-makers, growers, and other stakeholders with conducting precise land assessments by identifying the main limiting factors for the production of table grapes management and able to increase land productivity more precisely.

Keywords: vineyards, land physical suitability, socio-economic suitability, AHP

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680 Post-Covid 19 Pandemic Economy: Corporate Governance and Performance of Private Security Firms in Kenya

Authors: Sewe Silvanus Odhiambo

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Globally, many governments have publicly recognized private security firms as essential services providers. The private security firms face a lot of challenges, but the COVID-19 situation also has exacerbated them to another level. This paper locates its relevance in the post-coronavirus era. The COVID-19 pandemic has redefined the world operation, which shows a higher impact on the security field. Accordingly, the purpose of the study was to examine the role of corporate governance on the performance of private security firms in a post-covid pandemic era in Kenya. The study employed a descriptive research design, which included a quantitative approach and secondary data. The study was carried in the month of July 2021 from the registered private security firms. After targeting all private security firms, only 54 firms had disclosed their annual report by the time of conducting the study. The results depicted that pandemic has affected the performance of private security firms measures unfavorably. Further, boards of directors show a positive association with security firm performance. The study recommends that there is need board of directors to enhance management’s risk assessments in the midst of COVID-19; ensure that there are business continuity plans; there is organizational resilience; there is need for the development of new digital strategies; enabling the digital workforce in the firms and have effective communication plans with both internal and external stakeholders to deal with uncertainties and develop more post-COVID practices for boards of directors to improve performance of private security firms in Kenya. The practical implications of the study are that the research outcomes might assist regulatory bodies, investors, policymakers, and the security sector in general in their formulation of public and corporate governance strategies concerning future emergency preparedness and responses. This study also provides a unique contribution to the literature of COVID-19 and security firm performance in emerging economies context.

Keywords: COVID-19, corporate governance, firm performance, private security firms

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679 Realizing the Rights of Prisoners with Disabilities in Nigeria: A Case Study of Four Lagos State Prisons

Authors: Jacob Bogart, Adaobi Egboka

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Nigeria signed and ratified the Convention on the Rights of Persons with Disabilities in 2010, which was heralded as a much-needed step towards protecting the rights of persons with disabilities (PWDs). However, even with such progress, incarcerated PWDs have been left behind. The current legal framework in Nigeria does not consider the particular challenges PWDs face in prison nor make provisions to address them, despite the need for such reforms. Indeed, given the closed and restricted nature of prisons, and the violence that results from overcrowding, lack of supervision, and poor facilities, prisoners with disabilities often face significant challenges while incarcerated. While every prisoner is affected by these issues, PWDs are disproportionately harmed by them due to the nature of their disability. A study of four prisons in Lagos State, Nigeria was carried out by interviewing prisoners with disabilities, prison officials, advocates, and academics. The study found that for prisoners with physical disabilities, inaccessible prison facilities and a lack of mobility, hearing, or seeing assistance can often cause them to be dependent on the mercy of the other inmates for assistance in performing such basic functions as using the restroom, going to church, or washing themselves. Prison officials do not assist these PWDs or provide them with aids, such as crutches or a cane. Relatedly, prisoners with psychosocial disabilities (mental health conditions) often are not removed to health care facilities, despite a law to that effect, and are left to languish in prisons without the mental health care treatment they need. This presentation argues that reforms addressing the rights of PWDs must consider and make provisions for prisoners with disabilities, such as ensuring that prison facilities are accessible, providing PWDs with mobility, seeing or hearing aids as needed, and conducting mental health screenings for persons awaiting trial immediately upon entering the prison. These reforms, among others, are necessary first steps toward realizing the rights of prisoners with disabilities in Nigeria.

Keywords: disability rights, human rights, Lagos, Nigeria, prisoners with disabilities

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678 Applying Participatory Design for the Reuse of Deserted Community Spaces

Authors: Wei-Chieh Yeh, Yung-Tang Shen

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The concept of community building started in 1994 in Taiwan. After years of development, it fostered the notion of active local resident participation in community issues as co-operators, instead of minions. Participatory design gives participants more control in the decision-making process, helps to reduce the friction caused by arguments and assists in bringing different parties to consensus. This results in an increase in the efficiency of projects run in the community. Therefore, the participation of local residents is key to the success of community building. This study applied participatory design to develop plans for the reuse of deserted spaces in the community from the first stage of brainstorming for design ideas, making creative models to be employed later, through to the final stage of construction. After conducting a series of participatory designed activities, it aimed to integrate the different opinions of residents, develop a sense of belonging and reach a consensus. Besides this, it also aimed at building the residents’ awareness of their responsibilities for the environment and related issues of sustainable development. By reviewing relevant literature and understanding the history of related studies, the study formulated a theory. It took the “2012-2014 Changhua County Community Planner Counseling Program” as a case study to investigate the implementation process of participatory design. Research data are collected by document analysis, participants’ observation and in-depth interviews. After examining the three elements of “Design Participation”, “Construction Participation”, and” Follow–up Maintenance Participation” in the case, the study emerged with a promising conclusion: Maintenance works were carried out better compared to common public works. Besides this, maintenance costs were lower. Moreover, the works that residents were involved in were more creative. Most importantly, the community characteristics could be easy be recognized.

Keywords: participatory design, deserted space, community building, reuse

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677 Molecular Dynamics Studies of Main Factors Affecting Mass Transport Phenomena on Cathode of Polymer Electrolyte Membrane Fuel Cell

Authors: Jingjing Huang, Nengwei Li, Guanghua Wei, Jiabin You, Chao Wang, Junliang Zhang

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In this work, molecular dynamics (MD) simulation is applied to analyze the mass transport process in the cathode of proton exchange membrane fuel cell (PEMFC), of which all types of molecules situated in the cathode is considered. a reasonable and effective MD simulation process is provided, and models were built and compared using both Materials Studio and LAMMPS. The mass transport is one of the key issues in the study of proton exchange membrane fuel cells (PEMFCs). In this report, molecular dynamics (MD) simulation is applied to analyze the influence of Nafion ionomer distribution and Pt nano-particle size on mass transport process in the cathode. It is indicated by the diffusion coefficients calculation that a larger quantity of Nafion, as well as a higher equivalent weight (EW) value, will hinder the transport of oxygen. In addition, medium-sized Pt nano-particles (1.5~2nm) are more advantageous in terms of proton transport compared with other particle sizes (0.94~2.55nm) when the center-to-center distance between two Pt nano-particles is around 5 nm. Then mass transport channels are found to be formed between the hydrophobic backbone and the hydrophilic side chains of Nafion ionomer according to the radial distribution function (RDF) curves. And the morphology of these channels affected by the Pt size is believed to influence the transport of hydronium ions and, consequently the performance of PEMFC.

Keywords: cathode catalytic layer, mass transport, molecular dynamics, proton exchange membrane fuel cell

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676 Innovate, Educate, and Transform, Tailoring Sustainable Waste Handling Solutions for Nepal’s Small Populated Municipalities: Insights From Chandragiri Municipality

Authors: Anil Kumar Baral

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The research introduces a ground-breaking approach to waste management, emphasizing innovation, education, and transformation. Using Chandragiri Municipality as a case study, the study advocates a shift from traditional to progressive waste management strategies, contributing an inventive waste framework, sustainability advocacy, and a transformative blueprint. The waste composition analysis highlights Chandragiri's representative profile, leading to a comprehensive plan addressing challenges and recommending a transition to a profitable waste treatment model, supported by relevant statistics. The data-driven approach incorporates the official data of waste Composition from Chandragiri Municipality as secondary data and incorporates the primary data from Chandragiri households, ensuring a nuanced perspective. Discussions on implementation, viability, and environmental preservation underscore the dual benefit of sustainability. The study includes a comparative analysis, monitoring, and evaluation framework, examining international relevance and collaboration, and conducting a social and environmental impact assessment. The results indicate the necessity for creative changes in Chandragiri's waste practices, recommending separate treatment centers in wards level rather than Municipal level, composting machines, and a centralized waste treatment plant. Educational reforms involve revising school curricula and awareness campaigns. The transformation's success hinges on reducing waste size, efficient treatment center operation, and ongoing public literacy. The conclusion summarizes key findings, envisioning a future with sustainable waste management practices deeply embedded in the community fabric.

Keywords: innovate, educate, transform, municipality, method

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675 Dielectric, Electrical and Magnetic Properties of Elastomer Filled with in situ Thermally Reduced Graphene Oxide and Spinel Ferrite NiFe₂O₄ Nanoparticles

Authors: Raghvendra Singh Yadav, Ivo Kuritka, Jarmila Vilcakova, Pavel Urbanek, Michal Machovsky, David Skoda, Milan Masar

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The elastomer nanocomposites were synthesized by solution mixing method with an elastomer as a matrix and in situ thermally reduced graphene oxide (RGO) and spinel ferrite NiFe₂O₄ nanoparticles as filler. Spinel ferrite NiFe₂O₄ nanoparticles were prepared by the starch-assisted sol-gel auto-combustion method. The influence of filler on the microstructure, morphology, dielectric, electrical and magnetic properties of Reduced Graphene Oxide-Nickel Ferrite-Elastomer nanocomposite was characterized by X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, X-ray photoelectron spectroscopy, the Dielectric Impedance analyzer, and vibrating sample magnetometer. Scanning electron microscopy study revealed that the fillers were incorporated in elastomer matrix homogeneously. The dielectric constant and dielectric tangent loss of nanocomposites was decreased with the increase of frequency, whereas, the dielectric constant increases with the addition of filler. Further, AC conductivity was increased with the increase of frequency and addition of fillers. Furthermore, the prepared nanocomposites exhibited ferromagnetic behavior. This work was supported by the Ministry of Education, Youth and Sports of the Czech Republic – Program NPU I (LO1504).

Keywords: polymer-matrix composites, nanoparticles as filler, dielectric property, magnetic property

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674 Aitys as the Kazakh Traditional Music Genre in the Sense of Cognitive Musicology

Authors: Indira Makhazhan, Azamat Taigarayev, Perizat Yerlan, Batyrbay Gulbike, Samal Abzhanova

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Aitys is a competitional performance of two or more poets creating instantly the lyrics of music concerning the social issues accompanied with the traditional instrument dombra. It is an unique music genre, because it is not practical to create music and lyrics spontaneous in anywhere else. This research study tends to approach to this particular music genre Aitys and identify its significance not only in the sense of the Kazakh cultural heritage, but also from the perspective of personal development as the improvisational , oratory, public performance skills within the ability to think critically over the social problems and represent them in convenient to public form. Through conducting this research, this paper aims to reveal the importance and beneficence of aitys in terms of both prevalence of cultural heritage and its function in personal development of the singer. In order to answer to the research question, we conducted a survey and an in-depth interview with the students of Nazarbayev University. In the survey it was asked to answer the general questions about aitys and its importance, whereas in the interview part, we asked their opinion on the importance of aitys in improving the personal skills. The results of findings was more surprising than it was expected. They agreed that the aitys lessons, workshops and concerts have high outcomes in terms improvements of improvisational, oratory, and leadership skills. Students of NU as a representors of young generation have shown a great interest in aitys, and even more interested in the topics/social issues, where the poets have to defend their usually controversial position. To conclude, the research study has focused on the importance of the aitys in personal development of different leadership skills. The given research lead us to think about the aitys as a part of cognitive musicology, where within the learning of music it represents the process of cognition as well.

Keywords: aitys, cultural heritage, Kazakh language, musicology, personal development

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673 Unsteady Flow Simulations for Microchannel Design and Its Fabrication for Nanoparticle Synthesis

Authors: Mrinalini Amritkar, Disha Patil, Swapna Kulkarni, Sukratu Barve, Suresh Gosavi

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Micro-mixers play an important role in the lab-on-a-chip applications and micro total analysis systems to acquire the correct level of mixing for any given process. The mixing process can be classified as active or passive according to the use of external energy. Literature of microfluidics reports that most of the work is done on the models of steady laminar flow; however, the study of unsteady laminar flow is an active area of research at present. There are wide applications of this, out of which, we consider nanoparticle synthesis in micro-mixers. In this work, we have developed a model for unsteady flow to study the mixing performance of a passive micro mixer for reactants used for such synthesis. The model is developed in Finite Volume Method (FVM)-based software, OpenFOAM. The model is tested by carrying out the simulations at Re of 0.5. Mixing performance of the micro-mixer is investigated using simulated concentration values of mixed species across the width of the micro-mixer and calculating the variance across a line profile. Experimental validation is done by passing dyes through a Y shape micro-mixer fabricated using polydimethylsiloxane (PDMS) polymer and comparing variances with the simulated ones. Gold nanoparticles are later synthesized through the micro-mixer and collected at two different times leading to significantly different size distributions. These times match with the time scales over which reactant concentrations vary as obtained from simulations. Our simulations could thus be used to create design aids for passive micro-mixers used in nanoparticle synthesis.

Keywords: Lab-on-chip, LOC, micro-mixer, OpenFOAM, PDMS

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672 Improving Search Engine Performance by Removing Indexes to Malicious URLs

Authors: Durga Toshniwal, Lokesh Agrawal

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As the web continues to play an increasing role in information exchange, and conducting daily activities, computer users have become the target of miscreants which infects hosts with malware or adware for financial gains. Unfortunately, even a single visit to compromised web site enables the attacker to detect vulnerabilities in the user’s applications and force the downloading of multitude of malware binaries. We provide an approach to effectively scan the so-called drive-by downloads on the Internet. Drive-by downloads are result of URLs that attempt to exploit their visitors and cause malware to be installed and run automatically. To scan the web for malicious pages, the first step is to use a crawler to collect URLs that live on the Internet, and then to apply fast prefiltering techniques to reduce the amount of pages that are needed to be examined by precise, but slower, analysis tools (such as honey clients or antivirus programs). Although the technique is effective, it requires a substantial amount of resources. A main reason is that the crawler encounters many pages on the web that are legitimate and needs to be filtered. In this paper, to characterize the nature of this rising threat, we present implementation of a web crawler on Python, an approach to search the web more efficiently for pages that are likely to be malicious, filtering benign pages and passing remaining pages to antivirus program for detection of malwares. Our approaches starts from an initial seed of known, malicious web pages. Using these seeds, our system generates search engines queries to identify other malicious pages that are similar to the ones in the initial seed. By doing so, it leverages the crawling infrastructure of search engines to retrieve URLs that are much more likely to be malicious than a random page on the web. The results shows that this guided approach is able to identify malicious web pages more efficiently when compared to random crawling-based approaches.

Keywords: web crawler, malwares, seeds, drive-by-downloads, security

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671 Synthesis and Characterization of Some Novel Carbazole Schiff Bases (OLED)

Authors: Baki Cicek, Umit Calisir

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Carbazoles have been replaced lots of studies from 1960's to present and also still continues. In 1987, the first diode device had been developed. Thanks to that study, light emitting devices have been investigated and developed and also have been used on commercial applications. Nowadays, OLED (Organic Light Emitting Diodes) technology is using on lots of electronic screen such as (mobile phone, computer monitors, televisions, etc.) Carbazoles were subject a lot of study as a semiconductor material. Although this technology is used commen and widely, it is still development stage. Metal complexes of these compounds are using at pigment dyes because of colored substances, polymer technology, medicine industry, agriculture area, preparing rocket fuel-oil, determine some of biological events, etc. Becides all of these to preparing of schiff base synthesis is going on intensely. In this study, some of novel carbazole schiff bases were synthesized starting from carbazole. For that purpose, firstly, carbazole was alkylated. After purification of N-substituted-carbazole was nitrated to sythesized 3-nitro-N-substituted and 3,6-dinitro-N-substituted carbazoles. At next step, nitro group/groups were reduced to amines. Purified with using a type of silica gel-column chromatography. At the last step of our study, with sythesized 3,6-diamino-N-substituted carbazoles and 3-amino-N-substituted carbazoles were reacted with aldehydes to condensation reactions. 3-(imino-p-hydroxybenzyl)-N-isobutyl -carbazole, 3-(imino-2,3,4-trimethoxybenzene)-N-butylcarbazole, 3-(imino-3,4-dihydroxybenzene)-N-octylcarbazole, 3-(imino-2,3-dihydroxybenzene)-N-octylkarbazole and 3,6-di(α-imino-β-naphthol) -N-hexylcarbazole compounds were synthesized. All of synthesized compounds were characterized with FT-IR, 1H-NMR, 13C-NMR, and LC-MS.

Keywords: carbazole, carbazol schiff base, condensation reactions, OLED

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670 Valorisation of Waste Chicken Feathers: Electrospun Antibacterial Nanoparticles-Embedded Keratin Composite Nanofibers

Authors: Lebogang L. R. Mphahlele, Bruce B. Sithole

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Chicken meat is the highest consumed meat in south Africa, with a per capita consumption of >33 kg yearly. Hence, South Africa produces over 250 million kg of waste chicken feathers each year, the majority of which is landfilled or incinerated. The discarded feathers have caused environmental pollution and natural protein resource waste. Therefore, the valorisation of waste chicken feathers is measured as a more environmentally friendly and cost-effective treatment. Feather contains 91% protein, the main component being beta-keratin, a fibrous and insoluble structural protein extensively cross linked by disulfide bonds. Keratin is usually converted it into nanofibers via electrospinning for a variety of applications. keratin nanofiber composites have many potential biomedical applications for their attractive features, such as high surface-to-volume ratio and very high porosity. The application of nanofibers in the biomedical wound dressing requires antimicrobial properties for materials. One approach is incorporating inorganic nanoparticles, among which silver nanoparticles played an important alternative antibacterial agent and have been studied against many types of microbes. The objective of this study is to combine synthetic polymer, chicken feather keratin, and antibacterial nanoparticles to develop novel electrospun antibacterial nanofibrous composites for possible wound dressing application. Furthermore, this study will converting a two-dimensional electrospun nanofiber membrane to three-dimensional fiber networks that resemble the structure of the extracellular matrix (ECM)

Keywords: chicken feather keratin, nanofibers, nanoparticles, nanocomposites, wound dressing

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669 Robot-Assisted Laparoscopic Surgeries: Current Use in Pediatric Urology Patients

Authors: Rimel Mwamba, Mohan Gundeti

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Introduction: The use of robot-assisted laparoscopic surgeries (RALS) has largely increased in recent years, offering faster and safer treatment options for pediatric patients. In the field of urology, RALS has shown a significant advantage over laparoscopic and open surgeries but continues to be controversial in pediatric cases due to limited comprehensive data on its use. Methods: In this review, we aim to summarize the factors associated with RALS use in pediatric cases involving pyeloplasty, ureteral reimplantation, heminephrectomy, and lower urinary tract reconstruction. We used PubMed, EMBASE, and the Cochrane Database of Systematic Reviews to systematically search for literature on the topic. We then critically assessed and compiled data on RALS outcomes, complications, and associated factors. Results: To date, numerous comparative studies have been conducted on pediatric RALS, with only one randomized control trial investigating the nuances of robotic use against standard of care treatments. These robotic approaches have shown promise in post-surgical outcomes for pediatric patients undergoing upper and lower urinary tract reconstruction. Barriers to use still persist, however, showcasing a need to increase access to the technology, refine instruments for pediatric use, address cost barriers, and provide proper training for surgeons. Conclusion: RALS providesan opportunity to improve pediatric patient outcomes for numerous urologic complications. Additional studies are required to better compare the use of RALS with current standard practices. Due to the difficult nature of conducting randomized control trials, additional prospective observational studies are needed.

Keywords: pediatric urology, robot-assisted laparoscopic surgeries (RALS), pyeloplasty, ureteral reimplantation, heminephrectomy, and lower urinary tract reconstruction

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668 Intensive Intercultural English Language for Enhanced School Community Engagement: An Exploratory Study Applied to Parents from Language Backgrounds Other Than English in a Regional Australian Primary School

Authors: Ann Dashwood

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Using standard Australian English with confidence is a cultural expectation of parents of primary school aged children who want to engage effectively with their children’s teachers and school administration. That confidence in support of their children’s learning at school is seldom experienced by parents whose first language is not English. Sharing language with competence in an intercultural environment is the common denominator for meaningful communication and engagement to occur in a school community. Experience in relevant interactive sessions is known to enhance engagement and participation. The purpose of this paper is to identify interactional settings for which parents who are isolated from the daily use of functional Australian cultural language learned to engage more effectively in their children’s learning at school. The outcomes measured parents’ intercultural engagement with classroom teachers and attention to the school’s administrative procedures. The study used quantitative and qualitative methods. The principles of communicative task-based language learning combined with intercultural communication principles provided the theoretical base for intensive English task-based learning and engagement. The quantitative analysis examined data samples collected by classroom teachers and administrators and parents’ writing samples. Interviews and observations qualitatively informed the study. Currently significant numbers of projects are active in community centres and schools to enhance English language knowledge of parents from Language Backgrounds Other Than English (LBOTE). The study was significant to explore the effects of conducting intensive English with parents of varied English language backgrounds by targeting language use for social interactions in the community, specific engagement in school activities, cultural interaction with teachers and responsiveness to complying with school procedures.

Keywords: engagement, intercultural communication, LBOTE, school community

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667 A Comprehensive Analysis of the Rheological Properties of Polymer Hydrogels in Order to Explore Their Potential for Practical Utilization in Industries

Authors: Raana Babadi Fathipour

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Hydrogels are three-dimensional structures formed by the interweaving of polymeric materials, possessing the remarkable ability to imbibe copious amounts of water. Numerous methodologies have been devised for examining and understanding the properties of these synthesized gels. Amongst them, spectroscopic techniques such as ultraviolet/visible (UV/Vis) and Fourier-transform infrared (FTIR) spectroscopy offer a glimpse into molecular and atomic aspects. Additionally, diffraction methods like X-ray diffraction (XRD) enable one to measure crystallinity within the gel's structure, while microscopy tools encompassing scanning electron microscopy (SEM) and transmission electron microscopy (TEM) provide insights into surface texture and morphology. Furthermore, rheology serves as an invaluable tool for unraveling the viscoelastic behavior inherent in hydrogels—a parameter crucial not only to numerous industries, including pharmaceuticals, cosmetics, food processing, agriculture and water treatment, but also pivotal to related fields of research. Likewise, the ultimate configuration of the product is contingent upon its characterization at a microscopic scale in order to comprehend the intricacies of the hydrogel network's structure and interaction dynamics in response to external forces. Within this present scrutiny, our attention has been devoted to unraveling the intricate rheological tendencies exhibited by materials founded on synthetic, natural, and semi-synthetic hydrogels. We also explore their practical utilization within various facets of everyday life from an industrial perspective.

Keywords: rheology, hydrogels characterization, viscoelastic behavior, application

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666 Developing a Complete Profile: Vocational Assessment, Rehabilitation, and Management for Adults with Intellectual Disability in India

Authors: Virakti Dhaval Shah

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Advances in technology and the changes in lifestyle and work expectations amid the COVID-19 pandemic are requiring changes to vocational assessment, provision of vocational training, and identification of job matches for individuals with intellectual disability. Vocational assessment involves the assessment of interests, skills, abilities, and strengths/weaknesses, as well as a detailed understanding of healthcare, familial, social, community, workplace-related and policy-level protective and risk factors impacting the individual. In India, vocational assessment procedures such as interviews play a major role in vocational placement today. Unfortunately, many of the most widely used vocational assessment instruments in India were developed in the 1970s to 2000s and have not been revised since. Hence, there is a dire need to update existing tools and prepare a structured approach for vocational service providers to meet the unique employment needs of individuals with intellectual disabilities. To address this need, this project designed a multi-domain assessment toolkit for a structured approach to vocational assessment, training, and job placement for individuals with intellectual disabilities in India. Methods included conducting an empirical review of the available tools currently in use in India for the vocational assessment of persons with intellectual disabilities. Domains addressed in the instrument review were organized into a structured system, and additional items related to contemporary technology, pandemic-related experiences of persons with disabilities, and changes in lifestyle and work expectations due to the pandemic were added. Items assessing behaviors, provision of vocational training, and identification of job matches for individuals with intellectual disabilities were developed. The proposed tool has the potential to benefit organizations working with and preparing individuals with intellectual disabilities to find successful employment by undertaking a structured approach to vocational assessment, rehabilitation, training, and placement. It can be particularly useful for guiding new professionals doing vocational rehabilitation in India.

Keywords: intellectual disability, rehabilitation, vocational assessment, vocational rehabilitation

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665 Encapsulation of Probiotic Bacteria in Complex Coacervates

Authors: L. A. Bosnea, T. Moschakis, C. Biliaderis

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Two probiotic strains of Lactobacillus paracasei subsp. paracasei (E6) and Lactobacillus paraplantarum (B1), isolated from traditional Greek dairy products, were microencapsulated by complex coacervation using whey protein isolate (WPI, 3% w/v) and gum arabic (GA, 3% w/v) solutions mixed at different polymer ratio (1:1, 2:1 and 4:1). The effect of total biopolymer concentration on cell viability was assessed using WPI and GA solutions of 1, 3 and 6% w/v at a constant ratio of 2:1. Also, several parameters were examined for optimization of the microcapsule formation, such as inoculum concentration and the effect of ionic strength. The viability of the bacterial cells during heat treatment and under simulated gut conditions was also evaluated. Among the different WPI/GA weight ratios tested (1:1, 2:1, and 4:1), the highest survival rate was observed for the coacervate structures made with the ratio of 2:1. The protection efficiency at low pH values is influenced by both concentration and the ratio of the added biopolymers. Moreover, the inoculum concentration seems to affect the efficiency of microcapsules to entrap the bacterial cells since an optimum level was noted at less than 8 log cfu/ml. Generally, entrapment of lactobacilli in the complex coacervate structure enhanced the viability of the microorganisms when exposed to a low pH environment (pH 2.0). Both encapsulated strains retained high viability in simulated gastric juice (>73%), especially in comparison with non-encapsulated (free) cells (<19%). The encapsulated lactobacilli also exhibited enhanced viability after 10–30 min of heat treatment (65oC) as well as at different NaCl concentrations (pH 4.0). Overall, the results of this study suggest that complex coacervation with WPI/GA has a potential to deliver live probiotics in low pH food systems and fermented dairy products; the complexes can dissolve at pH 7.0 (gut environment), releasing the microbial cells.

Keywords: probiotic, complex coacervation, whey, encapsulation

Procedia PDF Downloads 281
664 Coordination of Traffic Signals on Arterial Streets in Duhok City

Authors: Dilshad Ali Mohammed, Ziyad Nayef Shamsulddin Aldoski, Millet Salim Mohammed

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The increase in levels of traffic congestion along urban signalized arterials needs efficient traffic management. The application of traffic signal coordination can improve the traffic operation and safety for a series of signalized intersection along the arterials. The objective of this study is to evaluate the benefits achievable through actuated traffic signal coordination and make a comparison in control delay against the same signalized intersection in case of being isolated. To accomplish this purpose, a series of eight signalized intersections located on two major arterials in Duhok City was chosen for conducting the study. Traffic data (traffic volumes, link and approach speeds, and passenger car equivalent) were collected at peak hours. Various methods had been used for collecting data such as video recording technique, moving vehicle method and manual methods. Geometric and signalization data were also collected for the purpose of the study. The coupling index had been calculated to check the coordination attainability, and then time space diagrams were constructed representing one-way coordination for the intersections on Barzani and Zakho Streets, and others represented two-way coordination for the intersections on Zakho Street with accepted progression bandwidth efficiency. The results of this study show great progression bandwidth of 54 seconds for east direction coordination and 17 seconds for west direction coordination on Barzani Street under suggested controlled speed of 60 kph agreeable with the present data. For Zakho Street, the progression bandwidth is 19 seconds for east direction coordination and 18 seconds for west direction coordination under suggested controlled speed of 40 kph. The results show that traffic signal coordination had led to high reduction in intersection control delays on both arterials.

Keywords: bandwidth, congestion, coordination, traffic, signals, streets

Procedia PDF Downloads 279
663 A Systematic Review of the Methodological and Reporting Quality of Case Series in Surgery

Authors: Riaz A. Agha, Alexander J. Fowler, Seon-Young Lee, Buket Gundogan, Katharine Whitehurst, Harkiran K. Sagoo, Kyung Jin Lee Jeong, Douglas G. Altman, Dennis P. Orgill

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Introduction: Case Series are an important and common study type. Currently, no guideline exists for reporting case series and there is evidence of key data being missed from such reports. We propose to develop a reporting guideline for case series using a methodologically robust technique. The first step in this process is a systematic review of literature relevant to the reporting deficiencies of case series. Methods: A systematic review of methodological and reporting quality in surgical case series was performed. The electronic search strategy was developed by an information specialist and included MEDLINE, EMBASE, Cochrane Methods Register, Science Citation index and Conference Proceedings Citation index, from the start of indexing until 5th November 2014. Independent screening, eligibility assessments and data extraction was performed. Included articles were analyzed for five areas of deficiency: failure to use standardized definitions missing or selective data transparency or incomplete reporting whether alternate study designs were considered. Results: The database searching identified 2,205 records. Through the process of screening and eligibility assessments, 92 articles met inclusion criteria. Frequency of methodological and reporting issues identified was a failure to use standardized definitions (57%), missing or selective data (66%), transparency, or incomplete reporting (70%), whether alternate study designs were considered (11%) and other issues (52%). Conclusion: The methodological and reporting quality of surgical case series needs improvement. Our data shows that clear evidence-based guidelines for the conduct and reporting of a case series may be useful to those planning or conducting them.

Keywords: case series, reporting quality, surgery, systematic review

Procedia PDF Downloads 347
662 EFL Teachers’ Sequential Self-Led Reflection and Possible Modifications in Their Classroom Management Practices

Authors: Sima Modirkhameneh, Mohammad Mohammadpanah

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In the process of EFL teachers’ development, self-led reflection (SLR) is thought to have an imperative role because it may help teachers analyze, evaluate, and contemplate what is happening in their classes. Such contemplations can not only enhance the quality of their instruction and provide better learning environments for learners but also improve the quality of their classroom management (CM). Accordingly, understanding the effect of teachers’ SLR practices may help us gain valuable insights into what possible modifications SLR may bring about in all aspects of EFL teachers' practitioners, especially their CM. The main purpose of this case study was, thus, to investigate the impact of SLR practices of 12 Iranian EFL teachers on their CM based on the universal classroom management checklist (UCMC). In addition, another objective of the current study was to have a clear image of EFL teachers’ perceptions of their own SLR practices and their possible outcomes. By conducting repeated reflective interviews, observations, and feedback of the participants over five teaching sessions, the researcher analyzed the outcomes qualitatively through the process of meaning categorization and data interpretation based on the principles of Grounded Theory. The results demonstrated that EFL teachers utilized SLR practices to improve different aspects of their language teaching skills and CM in different contexts. Almost all participants had positive comments and reactions about the effect of SLR on their CM procedures in different aspects (expectations and routines, behavior-specific praise, error corrections, prompts and precorrections, opportunity to respond, strengths and weaknesses of CM, teachers’ perception, CM ability, and learning process). Otherwise stated, results implied that familiarity with the UCMC criteria and reflective practices contributes to modifying teacher participants’ perceptions about their CM procedure and utilizing the reflective practices in their teaching styles. The results are thought to be valuably beneficial for teachers, teacher educators, and policymakers, who are recommended to pay special attention to the contributions as well as the complexity of reflective teaching. The study concludes with more detailed results and implications and useful directions for future research.

Keywords: classroom management, EFL teachers, reflective practices, self-led reflection

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661 Enhancing Transit Trade, Facilitation System and Supply Chain Security for Local, Regional and an International Corridor

Authors: Moh’d A. AL-Shboul

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Recently, and due to Arab spring and terrorism around the globe, pushing and driving most governments potentially to harmonize their border measures particularly the regional and an international transit trade within and among Customs Unions. The main purpose of this study is to investigate and provide an insight for monitoring and controlling the trade supply chain within and among different countries by using technological advancement (i.e. an electronic tracking system, etc.); furthermore, facilitate the local and intra-regional trade among countries through reviewing the recent trends and practical implementation of an electronic transit traffic and cargo that related to customs measures by introducing and supporting some case studies of several international and landlocked transit trade countries. The research methodology employed in this study was described as qualitative by conducting few interviews with managers, transit truck drivers, and traders and reviewing the related literature to collect qualitative data from secondary sources such as statistical reports, previous studies, etc. The results in this study show that Jordan and other countries around the globe that used an electronic tracking system for monitoring transit trade has led to a significant reduction in cost, effort and time in physical movement of goods internally and crossing through other countries. Therefore, there is no need to escort transit trucks by customs staff; hence, the rate of escort transit trucks is reduced by more than ninety percent, except the bulky and high duty goods. Electronic transit traffic has been increased; the average transit time journey has been reduced by more than seventy percent and has led to decrease in rates of smuggling up to fifty percent. The researcher recommends considering Jordan as regional and international office for tracking electronically and monitoring the transit trade for many considerations.

Keywords: electronic tracking system, facilitation system, regional and international corridor, supply chain security, transit trade

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660 Multi-Functional Metal Oxides as Gas Sensors, Photo-Catalysts and Bactericides

Authors: Koyar Rane

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Nano- to submicron size particles of narrow particle size distribution of semi-conducting TiO₂, ZnO, NiO, CuO, Fe₂O₃ have been synthesized by novel hydrazine method and tested for their gas sensing, photocatalytic and bactericidal activities and the behavior found to be enhanced when the oxides in the thin film forms, that obtained in a specially built spray pyrolysis reactor. Hydrazine method is novel in the sense, say, the UV absorption edge of the white pigment grade wide band gap (~3.2eV) TiO₂ and ZnO shifted to the visible region turning into yellowish particles, indicating modification occurring the band structure. The absorption in the visible region makes these oxides visible light sensitive photocatalysis in degrading pollutants, especially the organic dyes which otherwise increase the chemical oxygen demand of the drinking water, enabling the process feasible not under the harsh energetic UV radiation regime. The electromagnetic radiations on irradiation produce electron-hole pairs Semiconductor + hν → e⁻ + h⁺ The electron-hole pairs thus produced form Reactive Oxygen Species, ROS, on the surface of the semiconductors, O₂(adsorbed)+e⁻ → O₂• - superoxide ion OH-(surface)+h⁺ →•OH - Hydroxyl radical The ROS attack the organic material and micro-organisms. Our antibacterial studies indicate the metal oxides control the Biological Oxygen Demand (BOD) of drinking water which had beyond the safe level normally found in the municipal supply. Metal oxides in the thin film form show overall enhanced properties and the films are reusable. The results of the photodegradation and antibactericidal studies are discussed. Gas sensing studies too have been done to find the versatility of the multifunctional metal oxides.

Keywords: hydrazine method, visible light sensitive, photo-degradation of dyes, water/airborne pollutant

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659 Formulation and Evaluation of TDDS for Sustained Release Ondansetron HCL Patches

Authors: Baljinder Singh, Navneet Sharma

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The skin can be used as the site for drug administration for continuous transdermal drug infusion into the systemic circulation. For the continuous diffusion/penetration of the drugs through the intact skin surface membrane-moderated systems, matrix dispersion type systems, adhesive diffusion controlled systems and micro reservoir systems have been developed. Various penetration enhancers are used for the drug diffusion through skin. In matrix dispersion type systems, the drug is dispersed in the solvent along with the polymers and solvent allowed to evaporate forming a homogeneous drug-polymer matrix. Matrix type systems were developed in the present study. In the present work, an attempt has been made to develop a matrix-type transdermal therapeutic system comprising of ondansetron-HCl with different ratios of hydrophilic and hydrophobic polymeric combinations using solvent evaporation technique. The physicochemical compatibility of the drug and the polymers was studied by infrared spectroscopy. The results obtained showed no physical-chemical incompatibility between the drug and the polymers. The patches were further subjected to various physical evaluations along with the in-vitro permeation studies using rat skin. On the basis of results obtained form the in vitro study and physical evaluation, the patches containing hydrophilic polymers i.e. polyvinyl alcohol and poly vinyl pyrrolidone with oleic acid as the penetration enhancer(5%) were considered as suitable for large scale manufacturing with a backing layer and a suitable adhesive membrane.

Keywords: transdermal drug delivery, penetration enhancers, hydrophilic and hydrophobic polymers, ondansetron HCl

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658 When Conducting an Analysis of Workplace Incidents, It Is Imperative to Meticulously Calculate Both the Frequency and Severity of Injuries Sustain

Authors: Arash Yousefi

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Experts suggest that relying exclusively on parameters to convey a situation or establish a condition may not be adequate. Assessing and appraising incidents in a system based on accident parameters, such as accident frequency, lost workdays, or fatalities, may not always be precise and occasionally erroneous. The frequency rate of accidents is a metric that assesses the correlation between the number of accidents causing work-time loss due to injuries and the total working hours of personnel over a year. Traditionally, this has been calculated based on one million working hours, but the American Occupational Safety and Health Organization has updated its standards. The new coefficient of 200/000 working hours is now used to compute the frequency rate of accidents. It's crucial to ensure that the total working hours of employees are equally represented when calculating individual event and incident numbers. The accident severity rate is a metric used to determine the amount of time lost or wasted during a given period, often a year, in relation to the total number of working hours. It measures the percentage of work hours lost or wasted compared to the total number of useful working hours, which provides valuable insight into the number of days lost or wasted due to work-related incidents for each working hour. Calculating the severity of an incident can be difficult if a worker suffers permanent disability or death. To determine lost days, coefficients specified in the "tables of days equivalent to OSHA or ANSI standards" for disabling injuries are used. The accident frequency coefficient denotes the rate at which accidents occur, while the accident severity coefficient specifies the extent of damage and injury caused by these accidents. These coefficients are crucial in accurately assessing the magnitude and impact of accidents.

Keywords: incidents, safety, analysis, frequency, severity, injuries, determine

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657 Effects of Health Information Websites on Health Care Facility Visits

Authors: M. Aljumaan, F. Alkhadra, A. Aldajani, M. Alarfaj, A. Alawami, Y. Aljamaan

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Introduction: The internet has been widely available with 18 million users in Saudi Arabia alone. It was shown that 58% of Saudis are using the internet as a source of health-related information which may contribute to overcrowding of the Emergency Room (ER). Not many studies have been conducted to show the effect of online searching for health related information (HRI) and its role in influencing internet users to visit various health care facilities. So the main objective is to determine a correlation between HRI website use and health care facility visits in Saudi Arabia. Methodology: By conducting a cross sectional study and distributing a questionnaire, a total number of 1095 people were included in the study. Demographic data was collected as well as questions including the use of HRI websites, type of websites used, the reason behind the internet search, which health care facility it lead them to visit and whether seeking health information on the internet influenced their attitude towards visiting health care facilities. The survey was distributed using an internet survey applications. The data was then put on an excel sheet and analyzed with the help of a biostatician for making a correlation. Results: We found 91.4% of our population have used the internet for medical information using mainly General medical websites (77.8%), Forums (34.2%), Social Media (21.6%), and government websites (21.6%). We also found that 66.9% have used the internet for medical information to diagnose and treat their medical conditions on their own while 34.7% did so due to the inability to have a close referral and 29.5% due to their lack of time. Searching for health related information online caused 62.5% of people to visit health care facilities. Outpatient clinics were most visited at 77.9% followed by the ER (27.9%). The remaining 37.5% do not visit because using HRI websites reassure them of their condition. Conclusion: In conclusion, there may be a correlation between health information website use and health care facility visits. However, to avoid potentially inaccurate medical information, we believe doctors have an important role in educating their patients and the public on where to obtain the correct information & advertise the sites that are regulated by health care officials.

Keywords: ER visits, health related information, internet, medical websites

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656 A New Cytoprotective Drug on the Basis of Cytisine: Phase I Clinical Trial Results

Authors: B. Yermekbayeva, A. Gulyayaev, T. Nurgozhin, C. Bektur

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Cytisine aminophosphonate under the name "Cytafat" was approved for clinical trials in Republic of Kazakhstan as a putative liver protecting drug for the treatment of acute toxic hepatitis. A method of conducting the clinical trial is a double blind study. Total number of patients -71, aged from 16 to 56 years. Research on healthy volunteers determined the maximal tolerable doze of "Cytafat" as 200 mg/kg. Side effects when administered at high dozes (100-200 mg/kg) are tachycardia and increase of arterial blood pressure. The drug is tested in the treatment of 28 patients with a syndrome of hepatocellular failure (a poisoning with substitutes of alcohol, rat poison, or medical products). "Cytafat" was intravenously administered at a dose of 10 mg/kg in 200 ml of 5 % glucose solution once daily. The number of administrations: 1-3. In the comparison group, 23 patients were treated intravenously once a day with “Essenciale H” at a dose of 10 ml. 20 patients received a placebo (10 ml of glucose intravenously). In all cases of toxic hepatopathology the significant positive clinical effect of the testing drug distinguishable from placebo and surpassing the alternative was observed. Within a day after administration a sharp reduction of cytolitic syndrome parameters (ALT, AST, alkaline phosphatase, thymol turbidity test, GGT) was registered, a reduction of the severity of cholestatic syndrome (bilirubin decreased) was recorded, significantly decreased indices of lipid peroxidation. The following day, in all cases the positive dynamics was determined with ultrasound study (reduction of diffuse changes and events of reactive pancreatitis), hepatomegaly disappeared. Normalization of all parameters occurred in 2-3 times faster, than when using the drug "Essenciale H" and placebo. Average term of elimination of toxic hepatopathy when using the drug "Cytafat" -2,8 days, "Essenciale H" -7,2 days, and placebo -10,6 days. The new drug "Cytafat" has expressed cytoprotective properties.

Keywords: cytisine, cytoprotection, hepatopathy, hepatoprotection

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655 The Study of Magnetic and Transport Properties in Normal State Eu1.85+yCe0.15-yCu1-yFeyO4+α-δ

Authors: Risdiana, D. Suhendar, S. Pratiwi, W. A. Somantri, T. Saragi

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Superconductor is a promising material for future applications especially for energy saving because of their advantages properties such as zero electrical resistivity when they are cooled down to sufficiently low temperatures. However, the mechanism describing the role of physical properties in superconductor is far from being understood clearly, so that the application of this material for wider benefit in various industries is very limited. Most of superconductors are cuprate compounds, which has CuO2 as a conducting plane in their crystal structures. The study of physical properties through the partially substitution of impurity for Cu in superconducting cuprates has been one of great interests in relation to the mechanism of superconductivity. Different behaviors between the substitution of nonmagnetic impurity and magnetic impurity for Cu are observed. For examples, the superconductivity and Cu-spin fluctuations in the electron-doped system are suppressed through the substitution of magnetic Ni for Cu more markedly than through the substitution of nonmagnetic Zn for Cu, which is contrary to the result in the hole-doped system. Here, we reported the effect of partially substitution of magnetic impurity Fe for Cu to the magnetic and transport properties in electron-doped superconducting cuprates of Eu1.85+yCe0.15-yCu1-yFeyO4+α-δ (ECCFO) with y = 0.01, 0.02, and 0.05, in order to investigate the mechanism of magnetic and transport properties of ECCFO in normal-state. Magnetic properties are investigated by DC magnetic-susceptibility measurements that carried out at low temperatures down to 2 K using a standard SQUID magnetometer in a magnetic field of 5 Oe on field cooling. Transport properties addressed to electron mobility, are extracted from radius of electron localization calculated from temperature dependence of resistivity. For y = 0, temperature dependence of dc magnetic-susceptibility indicated the change of magnetic behavior from paramagnetic to diamagnetic below 15 K. Above 15 K, all samples show paramagnetic behavior with the values of magnetic moment in every volume unit increased with increasing y. Electron mobility decreased with increasing y. Some reasons for these results will be discussed.

Keywords: DC magnetic-susceptibility, electron mobility, Eu1.85+yCe0.15-yCu1-yFeyO4+α-δ, normal state

Procedia PDF Downloads 333