Search results for: materials jetting
Commenced in January 2007
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Edition: International
Paper Count: 6881

Search results for: materials jetting

1001 Criticality Assessment Model for Water Pipelines Using Fuzzy Analytical Network Process

Authors: A. Assad, T. Zayed

Abstract:

Water networks (WNs) are responsible of providing adequate amounts of safe, high quality, water to the public. As other critical infrastructure systems, WNs are subjected to deterioration which increases the number of breaks and leaks and lower water quality. In Canada, 35% of water assets require critical attention and there is a significant gap between the needed and the implemented investments. Thus, the need for efficient rehabilitation programs is becoming more urgent given the paradigm of aging infrastructure and tight budget. The first step towards developing such programs is to formulate a Performance Index that reflects the current condition of water assets along with its criticality. While numerous studies in the literature have focused on various aspects of condition assessment and reliability, limited efforts have investigated the criticality of such components. Critical water mains are those whose failure cause significant economic, environmental or social impacts on a community. Inclusion of criticality in computing the performance index will serve as a prioritizing tool for the optimum allocating of the available resources and budget. In this study, several social, economic, and environmental factors that dictate the criticality of a water pipelines have been elicited from analyzing the literature. Expert opinions were sought to provide pairwise comparisons of the importance of such factors. Subsequently, Fuzzy Logic along with Analytical Network Process (ANP) was utilized to calculate the weights of several criteria factors. Multi Attribute Utility Theories (MAUT) was then employed to integrate the aforementioned weights with the attribute values of several pipelines in Montreal WN. The result is a criticality index, 0-1, that quantifies the severity of the consequence of failure of each pipeline. A novel contribution of this approach is that it accounts for both the interdependency between criteria factors as well as the inherited uncertainties in calculating the criticality. The practical value of the current study is represented by the automated tool, Excel-MATLAB, which can be used by the utility managers and decision makers in planning for future maintenance and rehabilitation activities where high-level efficiency in use of materials and time resources is required.

Keywords: water networks, criticality assessment, asset management, fuzzy analytical network process

Procedia PDF Downloads 147
1000 Hydrogen Production By Photoreforming Of n-Butanol And Structural Isomers Over Pt Doped Titanate Catalyst

Authors: Hristina Šalipur, Jasmina Dostanić, Davor Lončarević, Matej Huš

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Photocatalytic water splitting/alcohol photoreforming has been used for the conversion of sunlight energy in the process of hydrogen production due to its sustainability, environmental safety, effectiveness and simplicity. Titanate nanotubes are frequently studied materials since they combine the properties of photo-active semiconductors with the properties of layered titanates, such as the ion-exchange ability. Platinum (Pt) doping into titanate structure has been considered an effective strategy in better separation efficiency of electron-hole pairs and lowering the overpotential for hydrogen production, which results in higher photocatalytic activity. In our work, Pt doped titanate catalysts were synthesized via simple alkaline hydrothermal treatment, incipient wetness impregnation method and temperature-programmed reduction. The structural, morphological and optical properties of the prepared catalysts were investigated using various characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 physisorption, and diffuse reflectance spectroscopy (DRS). The activities of the prepared Pt-doped titanate photocatalysts were tested for hydrogen production via photocatalytic water splitting/alcohol photoreforming process under simulated solar light irradiation. Characterization of synthesized Pt doped titanate catalysts showed crystalline anatase phase, preserved nanotubular structure and high specific surface area. The result showed enhancement of activity in photocatalytic water splitting/alcohol photoreforming in the following order 2-butanol>1-butanol>tert-butanol, with obtained maximal hydrogen production rate of 7.5, 5.3 and 2 mmol g-1 h-1, respectively. Different possible factors influencing the hole scavenging ability, such as hole scavenger redox potential and diffusivity, adsorption and desorption rate of the hole scavenger on the surface and stability of the alcohol radical species generated via hole scavenging, were investigated. The theoretical evaluation using density functional theory (DFT) further elucidated the reaction kinetics and detailed mechanism of photocatalytic water splitting/alcohol photoreforming.

Keywords: hydrogen production, platinum, semiconductor, water splitting, density functional theory

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999 Two-Component Biocompartible Material for Reconstruction of Articular Hyaline Cartilage

Authors: Alena O. Stepanova, Vera S. Chernonosova, Tatyana S. Godovikova, Konstantin A. Bulatov, Andrey Y. Patrushev, Pavel P. Laktionov

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Trauma and arthrosis, not to mention cartilage destruction in overweight and elders put hyaline cartilage lesion among the most frequent diseases of locomotor system. These problems combined with low regeneration potential of the cartilage make regeneration of articular cartilage a high-priority task of tissue engineering. Many types of matrices, the procedures of their installation and autologous chondrocyte implantation protocols were offered, but certain aspects including adhesion of the implant with surrounding cartilage/bone, prevention of the ossification and fibrosis were not resolved. Simplification and acceleration of the procedures resulting in restoration of normal cartilage are also required. We have demonstrated that human chondroblasts can be successfully cultivated at the surface of electrospun scaffolds and produce extracellular matrix components in contrast to chondroblasts grown in homogeneous hydrogels. To restore cartilage we offer to use stacks of electrospun scaffolds fixed with photopolymerized solution of prepared from gelatin and chondroitin-4-sulfate both modified by glycidyl methacrylate and non-toxic photoinitator Darocur 2959. Scaffolds were prepared from nylon 6, polylactide-co-glicolide and their mixtures with modified gelatin. Illumination of chondroblasts in photopolymerized solution using 365 nm LED light had no effect on cell viability at compressive strength of the gel less than0,12 MPa. Stacks of electrospun scaffolds provide good compressive strength and have the potential for substitution with cartilage when biodegradable scaffolds are used. Vascularization can be prevented by introduction of biostable scaffolds in the layers contacting the subchondral bone. Studies of two-component materials (2-3 sheets of electrospun scaffold) implanted in the knee-joints of rabbits and fixed by photopolymerization demonstrated good crush resistance, biocompatibility and good adhesion of the implant with surrounding cartilage. Histological examination of the implants 3 month after implantation demonstrates absence of any inflammation and signs of replacement of the biodegradable scaffolds with normal cartilage. The possibility of intraoperative population of the implants with autologous cells is being investigated.

Keywords: chondroblasts, electrospun scaffolds, hyaline cartilage, photopolymerized gel

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998 The Association Between CYP2C19 Gene Distribution and Medical Cannabis Treatment

Authors: Vichayada Laohapiboolkul

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Introduction: As the legal use of cannabis is being widely accepted throughout the world, medical cannabis has been explored in order to become an alternative cure for patients. Tetrahydrocannabinol (THC) and Cannabidiol (CBD) are natural cannabinoids found in the Cannabis plant which is proved to have positive treatment for various diseases and symptoms such as chronic pain, neuropathic pain, spasticity resulting from multiple sclerosis, reduce cancer-associated pain, autism spectrum disorders (ASD), dementia, cannabis and opioid dependence, psychoses/schizophrenia, general social anxiety, posttraumatic stress disorder, anorexia nervosa, attention-deficit hyperactivity disorder, and Tourette's disorder. Regardless of all the medical benefits, THC, if not metabolized, can lead to mild up to severe adverse drug reactions (ADR). The enzyme CYP2C19 was found to be one of the metabolizers of THC. However, the suballele CYP2C19*2 manifests as a poor metabolizer which could lead to higher levels of THC than usual, possibly leading to various ADRs. Objective: The aim of this study was to investigate the distribution of CYP2C19, specifically CYP2C19*2, genes in Thai patients treated with medical cannabis along with adverse drug reactions. Materials and Methods: Clinical data and EDTA whole blood for DNA extraction and genotyping were collected from patients for this study. CYP2C19*2 (681G>A, rs4244285) genotyping was conducted using the Real-time PCR (ABI, Foster City, CA, USA). Results: There were 42 medical cannabis-induced ADRs cases and 18 medical cannabis tolerance controls who were included in this study. A total of 60 patients were observed where 38 (63.3%) patients were female and 22 (36.7%) were male, with a range of age approximately 19 - 87 years. The most apparent ADRs for medical cannabis treatment were dry mouth/dry throat (76.7%), followed by tachycardia (70%), nausea (30%) and a few arrhythmias (10%). In the total of 27 cases, we found a frequency of 18 CYP2C19*1/*1 alleles (normal metabolizers, 66.7%), 8 CYP2C19*1/*2 alleles (intermediate metabolizers, 29.6%) and 1 CYP2C19*2/*2 alleles (poor metabolizers, 3.7%). Meanwhile, 63.6% of CYP2C19*1/*1, 36.3% and 0% of CYP2C19*1/*2 and *2/*2 in the tolerance controls group, respectively. Conclusions: This is the first study to confirm the distribution of CYP2C19*2 allele and the prevalence of poor metabolizer genes in Thai patients who received medical cannabis for treatment. Thus, CYP2C19 allele might serve as a pharmacogenetics marker for screening before initiating treatment.

Keywords: medical cannabis, adverse drug reactions, CYP2C19, tetrahydrocannabinol, poor metabolizer

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997 Public Art as Social Critique to Shape Urban-Scape

Authors: Po-Ching Wang

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Public art may be regarded as a social agenda. It is assumed that public art acts as an intermediate form that contributes significantly to community resurgence. That is, public art may be regarded as a verb/process or social intervention. It functions as a vanguard form, attacking boundaries and providing a sensibility for social strategy. Public art in tradition is generally expected to bring aesthetic pleasure to public. Contemporary public art, however, not only focuses on art installation, but it also often offers a process that aims to comment on, question, and challenge the socio-cultural status quo. During the last few decades, accelerated changes in the values and expectations brought to bear on varied urban issues, together with the destruction of the hegemony of traditional art and of museum authorities, has begun to contribute to freer and more democratic representations of public art. It is said that part of a public artwork’s role is to ruffle sacred feathers. In many cases, public art is created to address the dynamic social contradictions and mutability of public life; and artists and community participants approach public art from a variety of social critical perspectives and methodologies. Urban issues, such as social and environmental justice, health problems, violence, and political statements, provide plentiful source materials that fuel the performance of public art in many different settings. Further, public artworks have been extensively adopted to express social identity, make political statements, and/or to remedy social and environmental crises. Many murals on urban walls, for instance, reflect social conflicts and address civic rights, and these projects are usually the work of artists who though denied access to traditional gallery and museum channels are supported by community engagement and involvement. Public art as a social practice challenges the traditional western view of artistic practice. Art in the public realm creates a new media that provides a platform for a dialogical exchange between diverse social groups. It seems that public art has evolved as an arena for activism that addresses wide-ranging and highly controversial social issues and civilian concerns. The findings of this study indicate that public artworks are capable of playing a role of activist in facilitating community evolution via social progress.

Keywords: aesthetics, community regeneration, city development, publicness, public participation, social progress

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996 Ways to Effectively Use Tourism Potential Through International Marketing and PR Communication Strategy in the Post-pandemic Period (On the Example of Georgia)

Authors: Marine Kobalava

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The article analyzes the level of Georgia's tourism potential usage during the pandemic. The conclusion is drawnthat Georgia, as a tourism brand, is in a significant crisis at this stage, revenues from this sector have been substantially reduced, communication with potential customers is interrupted, no international marketing and PR communication strategies have been developed for the post-pandemic period. In order to rehabilitate the tourism industry of Georgia, it is considered vital to take measures using international marketing and PR communication strategies adjusted to the needs of the sectorthat will improve the use of tourism potential and stimulate the development of the sector. The goal of the research is to identify the factors hindering the use of tourism potential in the direction of international marketing and PR communication strategies in the post-pandemic period and to develop recommendations on ways to solve them. Research methods. The paper uses various theoretical and methodological tools of research, including Bibliographic research has been conducted on the main research issues; Analysis, synthesis, induction, and other methods are used to select and group data, identify similarities and differences, and identify trends; Endogenous and exogenous factors affecting the field of tourism have been studied by means of SWOT and PESTEL analyzes. A comparison model is used to analyze the strategy documents. Primary accounting materials are obtained from the National Statistics Office and the relevant ministries. Based on the results of the research, the directions of correct positioning of tourism products and marketing communication in the post-pandemic period have been developed. It is substantiated that a short-term international marketing strategy should include: probable goals of communication, maintaining a position on a potential traveler's “radar,” focusing communication on key motivating factors (gastronomy, winemaking, folklore, protected areas, mountainous regions). From a marketing point of view, it is important: holding international marketing events, compiling a list of target countries, formation of stimulus mechanisms, development of incentive programs for international tour operators, etc. The paper draws conclusions about the problems of using the tourism potential, recommendations on ways to solve this problems through international marketing and PR communication strategies are offered

Keywords: PR communication, international marketing strategy, tourism potential, post-pandemic period

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995 The Assessment of the Diabetes Mellitus Complications on Oral Health: A Longitudinal Study

Authors: Mimoza Canga, Irene Malagnino, Gresa Baboci, Edit Xhajanka, Vito Antonio Malagnino

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Background: Diabetes mellitus is regarded as a very problematic chronic disease that has an effect on a considerable number of people around the world and it is straightforwardly associated with the oral health condition of the patients. Objective: The objective of this study is to analyze and evaluate the impact of diabetes mellitus on oral health. Materials and methods: In the present research were taken into consideration 300 patients with an age range of 11 to 80 years old. The study sample was composed of 191 males, respectively 63.7% of them and 109 females 36.3% of the participants. We divided them into seven age groups: 11-20, 21-30, 31-40, 41-50, 51-60, 61-70, and 71-80 years.This descriptive and analytical research was designed as a longitudinal study. Statistical analysis was performed using IBM SPSS 23.0 statistics. Results: The majority of patients participating in the study belonged to the age range from 41 to 50 years old, precisely 20.7% of them, while 27% of the patients were from 51 to 60 years old. Based on the present research, it resulted that 24.4% of the participant had high blood sugar values 250-300 mg/dl, whereas 19 % of the patients had very high blood sugar values 300-350 mg/dl. Based on the results of the current study, it was observed that 83.7% of patients were affected by gingivitis. In the current study, the significant finding is that 22% of patients had more than 7 teeth with dental caries and 21% of them had 5-7 teeth with dental caries, whereas 29% of the patients had 4-5 dental caries and the remaining 28% of them had 1-3 dental caries. The present study showed that most of the patients, 27% of them had lost more than 7 teeth and 22% of the participants had lost 5-7 teeth, whereas 31% of the patients had lost 4-5 teeth and only 20 % of them had lost 1-3 teeth. This study proved that high blood sugar values had a direct impact on the manifestation of gingivitis and there it was a strong correlation between them with P-value = .001. A strong correlation was found out between dental caries and high blood sugar values with P-value ˂.001. Males with diabetes mellitus were more affected by dental caries and this was proved by the P-value= .02, in comparison to females P-value=.03. The impact of high blood sugar values affects missing teeth and the correlation between them was statistically significant with P-value ˂ .001. Conclusion: The results of this study suggest that diabetes mellitus is a possible risk factor in oral health for the reason that Albanian patients over 51 years old, respectively 43% of them have over 5 teeth with dental caries as compared with 49% of the patients who had over 5 missing teeth, whereas the majority 83.7% of them suffered from gingivitis. This study asserts that patients who do not have periodical check-ups of diabetes mellitus are at significant risk of oral diseases.

Keywords: dental caries, diabetes mellitus, gingivitis, missing teeth

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994 The Effectiveness of Warm-Water Footbath on Fatigue in Cancer Patient Undergoing Chemotherapy

Authors: Yu-Wen Lin, Li-Ni Liu

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Introduction: Fatigue is the most common symptoms experienced by cancer patients undergoing chemotherapy. Patients receiving anticancer therapies develop a higher proportion of fatigue compared with patients who do not receive anticancer therapies. Fatigue has significant impacts on quality of life, daily activities, mood status, and social behaviors. A warm-water footbath (WWF) at 41℃ promotes circulation and removes metabolites resulting in improving sleep and relieving fatigue. The aim of this study is to determine the effectiveness of WWF for relieving fatigue with cancer patients undergoing chemotherapy. Materials and Methods: This is a single-center, prospective, quasi-experimental design study in the oncology ward in Taiwan. Participants in this study were assigned to WWF group as experimental group and standard care group as a control group by purposive sampling. In the WWF group, the participants were asked to soak their feet in 42-43℃ water 15 minutes for consecutive 6 days at one day before chemotherapy. Each participant was evaluated for fatigue level by the Taiwanese version of the Brief Fatigue Inventory (BFI-T). BFI-T was completed for consecutive 8 days of the study. The primary outcome was compared the BFI-T score of WWF group to the standard care group. Results: There were 60 participants enrolled in this study. Thirty participants were assigned to WWF group and 30 participants were assigned to standard care group. Both groups have comparable characteristic. The BFI-T scores of both groups were increased associated with the days of chemotherapy. The highest BFI-T scores of both groups were on the day 4 of chemotherapy. The BFI-T scores of both groups were decreased since day 5 and significantly decreased in WWF group on day 5 compared to standard care group (4.17 vs. 5.7, P < .05). At the end of the study the fatigue at its worse were significantly decreased in WWF group (2.33 vs. 4.37, P < .001). There was no adverse event reported in this study. Conclusion: WWF is an easy, safe, non-invasive, and relatively inexpensive nursing intervention for improving fatigue of cancer patients undergoing chemotherapy. In summary, this study shows the WWF is a simple complementary care method, and it is effective for improving and relieving fatigue in a short time. Through improving fatigue is a way to enhance the quality of life which is important for cancer patients undergoing chemotherapy. Larger prospective randomized controlled trial and long-term effectiveness and outcomes of WWF should be performed to confirm this study.

Keywords: chemotherapy, warm-water footbath, fatigue, Taiwanese version of the brief fatigue inventory

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993 Comparative Analysis of Fused Deposition Modeling and Binding-Jet 3D Printing Technologies

Authors: Mohd Javaid, Shahbaz Khan, Abid Haleem

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Purpose: Large numbers of 3D printing technologies are now available for sophisticated applications in different fields. Additive manufacturing has established its dominance in design, development, and customisation of the product. In the era of developing technologies, there is a need to identify the appropriate technology for different application. In order to fulfil this need, two widely used printing technologies such as Fused Deposition Modeling (FDM), and Binding-Jet 3D Printing are compared for effective utilisation in the current scenario for different applications. Methodology: Systematic literature review conducted for both technologies with applications and associated factors enabling for the same. Appropriate MCDM tool is used to compare critical factors for both the technologies. Findings: Both technologies have their potential and capabilities to provide better direction to the industry. Additionally, this paper is helpful to develop a decision support system for the proper selection of technologies according to their continuum of applications and associated research and development capability. The vital issue is raw materials, and research-based material development is key to the sustainability of the developed technologies. FDM is a low-cost technology which provides high strength product as compared to binding jet technology. Researcher and companies can take benefits of this study to achieve the required applications in lesser resources. Limitations: Study has undertaken the comparison with the opinion of experts, which may not always be free from bias, and some own limitations of each technology. Originality: Comparison between these technologies will help to identify best-suited technology as per the customer requirements. It also provides development in this different field as per their extensive capability where these technologies can be successfully adopted. Conclusion: FDM and binding jet technology play an active role in industrial development. These help to assist the customisation and production of personalised parts cost-effectively. So, there is a need to understand how these technologies can provide these developments rapidly. These technologies help in easy changes or in making revised versions of the product, which is not easily possible in the conventional manufacturing system. High machine cost, the requirement of skilled human resources, low surface finish, and mechanical strength of product and material changing option is the main limitation of this technology. However, these limitations vary from technology to technology. In the future, these technologies are to be commercially viable for efficient usage in direct manufacturing of varied parts.

Keywords: 3D printing, comparison, fused deposition modeling, FDM, binding jet technology

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992 Rethinking Confucianism and Democracy

Authors: He Li

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Around the mid-1980s, Confucianism was reintroduced into China from Taiwan and Hong Kong as a result of China’s policies of reform and openness. Since then, the revival of neo-Confucianism in mainland China has accelerated and become a crucial component of the public intellectual sphere. The term xinrujia or xinruxue, loosely translated as “neo-Confucianism,” is increasingly understood as an intellectual and cultural phenomenon of the last four decades. The Confucian scholarship is in the process of restoration. This paper examines the Chinese intellectual discourse on Confucianism and democracy and places it in comparative and theoretical perspectives. With China’s rise and surge of populism in the West, particularly in the US, the leading political values of Confucianism could increasingly shape both China and the world at large. This state of affairs points to the need for more systematic efforts to assess the discourse on neo-Confucianism and its implications for China’s transformation. A number of scholars in the camp of neo-Confucianism maintain that some elements of Confucianism are not only compatible with democratic values and institutions but actually promote liberal democracy. They refer to it as Confucian democracy. By contrast, others either view Confucianism as a roadblock to democracy or envision that a convergence of democracy with Confucian values could result in a new hybrid system. The paper traces the complex interplay between Confucianism and democracy. It explores ideological differences between neo-Confucianism and liberal democracy and ascertains whether certain features of neo-Confucianism possess an affinity for the authoritarian political system. In addition to printed materials such as books and journal articles, a selection of articles from the website entitled Confucianism in China will be analyzed. The selection of this website is due to the fact that it is the leading website run by Chinese scholars focusing on neo-Confucianism. Another reason for selecting this website is its accessibility and availability. In the past few years, quite a few websites, left or right, were shut down by the authorities, but this website remains open. This paper explores the core components, dynamics, and implications of neo-Confucianism. My paper is divided into three parts. The first one discusses the origins of neo-Confucianism. The second section reviews the intellectual discourse among Chinese scholars on Confucian democracy. The third one explores the implications of the Chinese intellectual discourse on neo-Confucianism. Recently, liberal democracy has entered more conflict with official ideology. This paper, which is based on my extensive interviews in China prior to the pandemic and analysis of the primary sources in Chinese, will lay the foundation for a chapter on neo-Confucianism and democracy in my next book-length manuscript, tentatively entitled Chinese Intellectual Discourse on Democracy.

Keywords: China, confucius, confucianism, neo-confucianism, democracy

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991 Imaging Features of Hepatobiliary Histiocytosis

Authors: Ayda Youssef, Tarek Rafaat, Iman zaky

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Purpose: Langerhans’ cell histiocytosis (LCH) is not uncommon pathology that implies aberrant proliferation of a specific dendritic (Langerhans) cell. These atypical but mature cells of monoclonal origin can infiltrate many sites of the body and may occur as localized lesions or as widespread systemic disease. Liver is one of the uncommon sites of affection. The twofold objective of this study is to illustrate the radiological presentation of this disease, and to compare these results with previously reported series. Methods and Materials: Between 2007 and 2012, 150 patients with biopsy-proven LCH were treated in our hospital, a paediatric cancer tertiary care center. A retrospective review of radiographic images and reports was performed. There were 33 patients with liver affection are stratified. All patients underwent imaging studies, mostly US and CT. A chart review was performed to obtain demographic, clinical and radiological data. They were analyzed and compared to other published series. Results: Retrospective assessment of 150 patients with LCH was performed, among them 33 patients were identified who had liver involvement. All these patients developed multisystemic disease; They were 12 females and 21 males with (n= 32), seven of them had marked hepatomegaly. Diffuse hypodense liver parenchyma was encountered in five cases, the periportal location has a certain predilection in cases of focal affection where three cases has a hypodense periportal soft tissue sheets, one of them associated with dilated biliary radicals, only one case has multiple focal lesions unrelated to portal tracts. On follow up of the patients, two cases show abnormal morphology of liver with bossy outline. Conclusion: LCH is a not infrequent disease. A high-index suspicion should be raised in the context of diagnosis of liver affection. A biopsy is recommended in the presence of radiological suspicion. Chemotherapy is the preferred therapeutic modality. Liver histiocytosis are not disease specific features but should be interpreted in conjunction with the clinical history and the results of biopsy. Clinical Relevance/Application: Radiologist should be aware of different patterns of hepatobiliary histiocytosis, Thus early diagnosis and proper management of patient can be conducted.

Keywords: langerhans’ cell histiocytosis, liver, medical and health sciences, radiology

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990 Project Work with Design Thinking and Blended Learning: A Practical Report from Teaching in Higher Education

Authors: C. Vogeler

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Change processes such as individualization and digitalization have an impact on higher education. Graduates are expected to cooperate in creative work processes in their professional life. During their studies, they need to be prepared accordingly. This includes modern learning scenarios that integrate the benefits of digital media. Therefore, design thinking and blended learning have been combined in the project-based seminar conception introduced here. The presented seminar conception has been realized and evaluated with students of information sciences since September 2017. Within the seminar, the students learn to work on a project. They apply the methods in a problem-based learning scenario. Task of the case study is to arrange a conference on the topic gaming in libraries. In order to collaborative develop creative possibilities of realization within the group of students the design thinking method has been chosen. Design thinking is a method, used to create user-centric, problem-solving and need-driven innovation through creative collaboration in multidisciplinary teams. Central characteristics are the openness of this approach to work results and the visualization of ideas. This approach is now also accepted in the field of higher education. Especially in problem-based learning scenarios, the method offers clearly defined process steps for creative ideas and their realization. The creative process can be supported by digital media, such as search engines and tools for the documentation of brainstorming, creation of mind maps, project management etc. Because the students have to do two-thirds of the workload in their private study, design thinking has been combined with a blended learning approach. This supports students’ preparation and follow-up of the joint work in workshops (flipped classroom scenario) as well as the communication and collaboration during the entire project work phase. For this purpose, learning materials are provided on a Moodle-based learning platform as well as various tools that supported the design thinking process as described above. In this paper, the seminar conception with a combination of design thinking and blended learning is described and the potentials and limitations of the chosen strategy for the development of a course with a multimedia approach in higher education are reflected.

Keywords: blended learning, design thinking, digital media tools and methods, flipped classroom

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989 Surface Enhanced Infrared Absorption for Detection of Ultra Trace of 3,4- Methylene Dioxy- Methamphetamine (MDMA)

Authors: Sultan Ben Jaber

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Optical properties of molecules exhibit dramatic changes when adsorbed close to nano-structure metallic surfaces such as gold and silver nanomaterial. This phenomena opened a wide range of research to improve conventional spectroscopies efficiency. A well-known technique that has an intensive focus of study is surface-enhanced Raman spectroscopy (SERS), as since the first observation of SERS phenomena, researchers have published a great number of articles about the potential mechanisms behind this effect as well as developing materials to maximize the enhancement. Infrared and Raman spectroscopy are complementary techniques; thus, surface-enhanced infrared absorption (SEIRA) also shows a noticeable enhancement of molecules in the mid-IR excitation on nonmetallic structure substrates. In the SEIRA, vibrational modes that gave change in dipole moments perpendicular to the nano-metallic substrate enhanced 200 times greater than the free molecule’s modes. SEIRA spectroscopy is promising for the characterization and identification of adsorbed molecules on metallic surfaces, especially at trace levels. IR reflection-absorption spectroscopy (IRAS) is a well-known technique for measuring IR spectra of adsorbed molecules on metallic surfaces. However, SEIRA spectroscopy sensitivity is up to 50 times higher than IRAS. SEIRA enhancement has been observed for a wide range of molecules adsorbed on metallic substrates such as Au, Ag, Pd, Pt, Al, and Ni, but Au and Ag substrates exhibited the highest enhancement among the other mentioned substrates. In this work, trace levels of 3,4-methylenedioxymethamphetamine (MDMA) have been detected using gold nanoparticles (AuNPs) substrates with surface-enhanced infrared absorption (SEIRA). AuNPs were first prepared and washed, then mixed with different concentrations of MDMA samples. The process of fabricating the substrate prior SEIRA measurements included mixing of AuNPs and MDMA samples followed by vigorous stirring. The stirring step is particularly crucial, as stirring allows molecules to be robustly adsorbed on AuNPs. Thus, remarkable SEIRA was observed for MDMA samples even at trace levels, showing the rigidity of our approach to preparing SEIRA substrates.

Keywords: surface-enhanced infrared absorption (SEIRA), gold nanoparticles (AuNPs), amphetamines, methylene dioxy- methamphetamine (MDMA), enhancement factor

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988 The Investigation of Endogenous Intoxication and Lipid Peroxidation in Patients with Giardiasis Before and After Treatment

Authors: R. H. Begaydarova, B. Zh. Kultanov, B. T. Esilbaeva, G. E. Nasakaeva, Y. Yukhnevich, G. K. Alshynbekova, A. E. Dyusembaeva

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Background: The level of middle molecules of peptides (MMP) allows to evaluate the severity and prognosis of the disease and is a criterion for the effectiveness of the treatment. The detection the products of lipidperoxidation cascade, such as conjugated dienes, malondialdehyde in biological material, has an important role in the development of pathogenesis, the diagnosis and prognosis in different parasitic diseases. Purpose of the study was to evaluate the state of endogenous intoxication and indicators of lipid peroxidation in patients with giardiasis before and after treatment. Materials and methods: Endogenous intoxication was evaluated in patients with giardiasis in the level of middle molecules of peptides (MMP) in the blood. The amount of MMP and products of lipid peroxidation were determined in the blood of 198 patients with giardiasis, 129 of them were women (65%), 69 were men (35%). The MMP level was detected for comparison in the blood of 84 healthy volunteers. The lipid peroxidation were determined in 40 healthy men and women without giardiasis and history of chronic diseases. Data were processed by conventional methods of variation statistics, we calculated the arithmetic mean (M) and standard dispersion (m). t-test (t) was used to assess differences. Results: The level of MMP in the blood was significantly higher in patients with giardiasis in comparison with group of healthy men and women. MMP concentration in the blood of women with Giardia was 2.5 times greater than that of the comparison groups of women. The level of MMP exceeds more than 6 times in men with giardiasis. The decrease in the intensity of endogenous intoxication was two weeks after antigiardia therapy, both men and women. According to the study, a statistically significant increase in the level of all the studied parameters lipid peroxidation cascade was observed in the blood of men with giardiasis, with the exception of the total primary production (NGN). The treatment of giardiasis helped to stabilize the level of almost all metabolites of lipid peroxidation cascade. The exception was level of malondialdehyde, it was significantly elevated to compare with the control group and after treatment. Conclusion: Thus, the MMP level was significantly higher in blood of patients with giardiasis than in comparison group. This is evidence of severe endogenous intoxication caused by giardia infection. The accumulation of primary and secondary products of lipid peroxidation was observed in the blood of men and women. These processes tend to be more active in men than in women. Antigiardiasis therapy contributed to the normalization of almost all the studied indicators of lipid peroxidation in the blood of participants, except the level malondialdehyde in the blood of men.

Keywords: enzymes of antioxidant protection, giardiasis, blood, treatment

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987 Engineering the Topological Insulator Structures for Terahertz Detectors

Authors: M. Marchewka

Abstract:

The article is devoted to the possible optical transitions in double quantum wells system based on HgTe/HgCd(Mn)Te heterostructures. Such structures can find applications as detectors and sources of radiation in the terahertz range. The Double Quantum Wells (DQW) systems consist of two QWs separated by the transparent for electrons barrier. Such systems look promising from the point of view of the additional degrees of freedom. In the case of the topological insulator in about 6.4nm wide HgTe QW or strained 3D HgTe films at the interfaces, the topologically protected surface states appear at the interfaces/surfaces. Electrons in those edge states move along the interfaces/surfaces without backscattering due to time-reversal symmetry. Combination of the topological properties, which was already verified by the experimental way, together with the very well know properties of the DQWs, can be very interesting from the applications point of view, especially in the THz area. It is important that at the present stage, the technology makes it possible to create high-quality structures of this type, and intensive experimental and theoretical studies of their properties are already underway. The idea presented in this paper is based on the eight-band KP model, including the additional terms related to the structural inversion asymmetry, interfaces inversion asymmetry, the influence of the magnetically content, and the uniaxial strain describe the full pictures of the possible real structure. All of this term, together with the external electric field, can be sources of breaking symmetry in investigated materials. Using the 8 band KP model, we investigated the electronic shape structure with and without magnetic field from the application point of view as a THz detector in a small magnetic field (below 2T). We believe that such structures are the way to get the tunable topological insulators and the multilayer topological insulator. Using the one-dimensional electrons at the topologically protected interface states as fast and collision-free signal carriers as charge and signal carriers, the detection of the optical signal should be fast, which is very important in the high-resolution detection of signals in the THz range. The proposed engineering of the investigated structures is now one of the important steps on the way to get the proper structures with predicted properties.

Keywords: topological insulator, THz spectroscopy, KP model, II-VI compounds

Procedia PDF Downloads 122
986 Development of Electrochemical Biosensor Based on Dendrimer-Magnetic Nanoparticles for Detection of Alpha-Fetoprotein

Authors: Priyal Chikhaliwala, Sudeshna Chandra

Abstract:

Liver cancer is one of the most common malignant tumors with poor prognosis. This is because liver cancer does not exhibit any symptoms in early stage of disease. Increased serum level of AFP is clinically considered as a diagnostic marker for liver malignancy. The present diagnostic modalities include various types of immunoassays, radiological studies, and biopsy. However, these tests undergo slow response times, require significant sample volumes, achieve limited sensitivity and ultimately become expensive and burdensome to patients. Considering all these aspects, electrochemical biosensors based on dendrimer-magnetic nanoparticles (MNPs) was designed. Dendrimers are novel nano-sized, three-dimensional molecules with monodispersed structures. Poly-amidoamine (PAMAM) dendrimers with eight –NH₂ groups using ethylenediamine as a core molecule were synthesized using Michael addition reaction. Dendrimers provide added the advantage of not only stabilizing Fe₃O₄ NPs but also displays capability of performing multiple electron redox events and binding multiple biological ligands to its dendritic end-surface. Fe₃O₄ NPs due to its superparamagnetic behavior can be exploited for magneto-separation process. Fe₃O₄ NPs were stabilized with PAMAM dendrimer by in situ co-precipitation method. The surface coating was examined by FT-IR, XRD, VSM, and TGA analysis. Electrochemical behavior and kinetic studies were evaluated using CV which revealed that the dendrimer-Fe₃O₄ NPs can be looked upon as electrochemically active materials. Electrochemical immunosensor was designed by immobilizing anti-AFP onto dendrimer-MNPs by gluteraldehyde conjugation reaction. The bioconjugates were then incubated with AFP antigen. The immunosensor was characterized electrochemically indicating successful immuno-binding events. The binding events were also further studied using magnetic particle imaging (MPI) which is a novel imaging modality in which Fe₃O₄ NPs are used as tracer molecules with positive contrast. Multicolor MPI was able to clearly localize AFP antigen and antibody and its binding successfully. Results demonstrate immense potential in terms of biosensing and enabling MPI of AFP in clinical diagnosis.

Keywords: alpha-fetoprotein, dendrimers, electrochemical biosensors, magnetic nanoparticles

Procedia PDF Downloads 136
985 Development of Two Phage Therapy-Based Strategies for the Treatment of American Foulbrood Disease Affecting Apis Mellifera capensis

Authors: Ridwaan N. Milase, Leonardo J. Van Zyl, Marla Trindade

Abstract:

American foulbrood (AFB) is the world’s most devastating honeybee disease that has drastically reduced the population of Apis mellifera capensis since 2009. The outbreak has jeopardized the South African bee keeping industry as well as the agricultural sector dependent on honeybees for honey production and pollination, leading to significant economic losses. AFB is caused by Paenibacillus larvae, a spore-forming, Gram positive facultative anaerobic and flagellated bacterium. The use of antibiotics within beehives has selected for resistant strains of P. larvae, while the current practice of burning spore contaminated beehives and equipment contributes to the economic losses in the honeybee-keeping industry. Therefore, phage therapy is proposed as a promising alternative to combat P. larvae strains affecting A. mellifera capensis. The genomes of two P. larvae strains isolated from infected combs in the Western Cape have been sequenced and annotated using bioinformatics tools. Genome analyses has revealed that these P. larvae strains are lysogens to more than 6 different prophages and possess different type of clustered regularly interspaced short palindromic repeat (CRISPRs) regions per strain. Active prophages from one of the two P. larvae strains were detected and identified using PCR. Electron microscopy was used to determine the family of the identified active prophages. Lytic bacteriophages that specifically target the two P. larvae strains were purified from sewage wastewater, beehive materials, and soil samples to investigate their potential development as anti-P. larvae agents. Another alternative treatment being investigated is the development of a prophage endolysin cocktail. Endolysin genes of the prophages have been targeted, cloned and expressed in Escherichia coli. The heterologously expressed endolysins have been purified and are currently being assessed for their lytic activity against P. larvae strains and other commensal microorganisms that compose the honeybee larvae microbiota. The study has shown that phage therapy and endolysins have a great potential as alternative control methods for AFB disease affecting A. mellifera capensis.

Keywords: American foulbrood, bacteriophage, honeybee, Paenibacillus larvae

Procedia PDF Downloads 181
984 Antifungal Potential of Higher Basidiomycetes Mushrooms

Authors: Tamar Khardziani, Violeta Berikashvili, Mariam Rusitashvili, Eva Kachlishvili, Vladimir Elisashvili, Mikheil Asatiani

Abstract:

Last years, the search for natural sources of novel and effective antifungal substances became a scientific and technological challenge. In the present research, thirty basidiomycetes isolated from various ecological niches of Georgia and belonging to different taxonomic groups were screened for their antifungal activities against pathogenic fungi such as Aspergillus, Fusarium, and Guignardia bidwellii. Among mushroom tested, several potential producers of antifungal substances have been revealed, such as Schizophyllum commune, Lentinula edodes, Ganoderma abietinum, Fomes fomentarius, Hericium erinaceus, and Trametes versicolor. For mushroom cultivation and expression of antifungal potential, submerged and solid-state fermentations of different plant raw materials were performed and various approaches and strategies have been exploited. Sch. commune appeared as a most promising producer of antifungal compounds. It was established that among different agro-industrial wastes, the presence of mandarin juice production waste in a nutrient medium, causing the significant increase of antifungal activity Sch. commune (growth inhibition: Aspergillus – 59 %, Fusarium – 55 %, G. bidwellii – 78 %, after 3, 2 and 4 days of cultivation, respectively). Besides this, Sch. commune demonstrate similar antifungal activities in the presence of glucose, glycerol, maltose, mannitol, and xylose, and growth inhibition of Fusarium ranged in 41 % - 49 % during 6 days of cultivation. Inhibition of Aspergillus growth inhibition varied in 27 % - 36 %, and inhibition of G. bidwellii was in the range 49 % - 61 %, respectively. Sch. commune under solid-state fermentation of mandarin peels at 13 days of cultivation demonstrates powerful growth inhibition of pathogenic fungi (growth inhibition: Aspergillus – 50 %, Fusarium – 61 %, G. bidwellii – 68 %, after 3, 4, and 4 days of cultivation, respectively) as well as at 20 days old mushroom (growth inhibition: Aspergillus – 41 %, Fusarium – 54 %, G. bidwellii – 66 %, after 3 days of cultivation). It was established that Sch. commune was effective as a producer of antifungal compounds in submerged as well as in solid-state fermentation. Finally, performed study confirms that the higher basidiomycetes possess antifungal potential, which strongly depends on the physiological factors of growth. Acknowledgments: The work was implemented with the financial support of fundamental science project FR-19-3719 by the Shota Rustaveli National Science Foundation of Georgia.

Keywords: antifungal potential, higher basidiomycetes, pathogenic fungi, submerged and solid-state fermentation

Procedia PDF Downloads 144
983 Limos Lactobacillus Fermentum from Buffalo Milk Is Suitable for Potential Biotechnological Process Development

Authors: Sergio D’Ambrosioa, Azza Dobousa, Chiara Schiraldia, Donatella Ciminib

Abstract:

Probiotics are living microorganisms that give beneficial effects while consumed. Lactic acid bacteria and bifidobacteria are among the most representative strains assessed as probiotics and exploited as food supplements. Numerous studies demonstrated their potential as a therapeutic candidate for a variety of diseases (restoring gut flora, lowering cholesterol, immune response-enhancing, anti-inflammation and anti-oxidation activities). These beneficial actions are also due to biomolecules produced by probiotics, such as exopolysaccharides (EPSs), that demonstrate plenty of beneficial properties such as antimicrobial, antitumor, anti-biofilm, antiviral and immunomodulatory activities. Limosilactobacillus fermentum is a widely studied member of probiotics; however, few data are available on the development of fermentation and downstream processes for the production of viable biomasses for potential industrial applications. However, few data are available on the development of fermentation processes for the large-scale production of probiotics biomass for industrial applications and for purification processes of EPSs at an industrial scale. For this purpose, L. fermentum strain was isolated from buffalo milk and used as a test example for biotechnological process development. The strain was able to produce up to 109 CFU/mL on a (glucose-based) semi-defined medium deprived of animal-derived raw materials up to the pilot scale (150 L), demonstrating improved results compared to commonly used, although industrially not suitable, media-rich of casein and beef extract. Biomass concentration via microfiltration on hollow fibers, and subsequent spray-drying allowed to recover of about 5.7 × 1010CFU/gpowder of viable cells, indicating strain resistance to harsh processing conditions. Overall, these data demonstrate the possibility of obtaining and maintaining adequate levels of viable L. fermentum cells by using a simple approach that is potentially suitable for industrial development. A downstream EPS purification protocol based on ultrafiltration, precipitation and activated charcoal treatments showed a purity of the recovered polysaccharides of about 70-80%.

Keywords: probiotics, fermentation, exopolysaccharides (EPSs), purification

Procedia PDF Downloads 83
982 Synthesis, Characterization and Photocatalytic Applications of Ag-Doped-SnO₂ Nanoparticles by Sol-Gel Method

Authors: M. S. Abd El-Sadek, M. A. Omar, Gharib M. Taha

Abstract:

In recent years, photocatalytic degradation of various kinds of organic and inorganic pollutants using semiconductor powders as photocatalysts has been extensively studied. Owing to its relatively high photocatalytic activity, biological and chemical stability, low cost, nonpoisonous and long stable life, Tin oxide materials have been widely used as catalysts in chemical reactions, including synthesis of vinyl ketone, oxidation of methanol and so on. Tin oxide (SnO₂), with a rutile-type crystalline structure, is an n-type wide band gap (3.6 eV) semiconductor that presents a proper combination of chemical, electronic and optical properties that make it advantageous in several applications. In the present work, SnO₂ nanoparticles were synthesized at room temperature by the sol-gel process and thermohydrolysis of SnCl₂ in isopropanol by controlling the crystallite size through calculations. The synthesized nanoparticles were identified by using XRD analysis, TEM, FT-IR, and Uv-Visible spectroscopic techniques. The crystalline structure and grain size of the synthesized samples were analyzed by X-Ray diffraction analysis (XRD) and the XRD patterns confirmed the presence of tetragonal phase SnO₂. In this study, Methylene blue degradation was tested by using SnO₂ nanoparticles (at different calculations temperatures) as a photocatalyst under sunlight as a source of irradiation. The results showed that the highest percentage of degradation of Methylene blue dye was obtained by using SnO₂ photocatalyst at calculations temperature 800 ᵒC. The operational parameters were investigated to be optimized to the best conditions which result in complete removal of organic pollutants from aqueous solution. It was found that the degradation of dyes depends on several parameters such as irradiation time, initial dye concentration, the dose of the catalyst and the presence of metals such as silver as a dopant and its concentration. Percent degradation was increased with irradiation time. The degradation efficiency decreased as the initial concentration of the dye increased. The degradation efficiency increased as the dose of the catalyst increased to a certain level and by further increasing the SnO₂ photocatalyst dose, the degradation efficiency is decreased. The best degradation efficiency on which obtained from pure SnO₂ compared with SnO₂ which doped by different percentage of Ag.

Keywords: SnO₂ nanoparticles, a sol-gel method, photocatalytic applications, methylene blue, degradation efficiency

Procedia PDF Downloads 152
981 Influence of Gender Inequality on Pre – Primary School Children’s Literacy Skills Development in Ojo Local Government Area, Lagos State

Authors: Morenikeji Aliu Balaji

Abstract:

Gender inequality is seen as persistent discrimination of one group of people based gender, and it manifests itself differently according to race, culture, politics, country and economic situation. Multiple explanations have been offered for gender differences in literacy skill development. Three prominent explanations that precipitated the gender differences are; biological, where the assumption is that differential brain structures and hemispheric activation patterns cause the sexes to be hardwired differently for reading, with girls developing the cognitive skills associated with reading before boys. Secondly, schooling favour girls and ‘girly’ behaviour, and that boys are, as a result, lagging behind on several behavioural, social and academic measures and thirdly, cultural influences, where literacy is defined as a feminine characteristic – propagated by an overrepresentation of female teachers – and that modern culture steers boys towards activities such as sport and computers. Therefore the study investigated the influence of gender inequality on pre – primary school children literacy skills development in Ojo Local Government Area, Lagos State. Descriptive survey research design was adopted for the study. 100 pre-primary school teachers were involved in the study. A self-designed instrument was used for data collection titled ‘Influence of Gender Inequality on Literacy Skill Development in Children Questionnaire (IGILSDCQ)’. The instrument was validated and tested for reliability. The reliability index for IGILSDCQ (α = 0.79). Five research questions were answered using descriptive (frequency count, simple percentage, mean and standard deviation). The findings showed that that gender inequality to some extent influence children phonemic awareness (WA=1.76), the extent to which gender inequality influence children awareness of print is high (WA=2.8), gender inequality to some extent influence children vocabulary development (WA = 2.4), the extent to which gender inequality influence children speaking skill development is high (WA = 2.5) and lastly, the extent to which gender inequality influence children comprehension ability is high (WA = 2.5). It was recommended among others that effort by the school administrators is necessary in the provision of reading materials and literacy skill development packages that are both male-oriented and female-oriented.

Keywords: pre-primart, literacy, awareness, phonemic, gender

Procedia PDF Downloads 28
980 Cluster Analysis and Benchmarking for Performance Optimization of a Pyrochlore Processing Unit

Authors: Ana C. R. P. Ferreira, Adriano H. P. Pereira

Abstract:

Given the frequent variation of mineral properties throughout the Araxá pyrochlore deposit, even if a good homogenization work has been carried out before feeding the processing plants, an operation with quality and performance’s high variety standard is expected. These results could be improved and standardized if the blend composition parameters that most influence the processing route are determined, and then the types of raw materials are grouped by them, finally presenting a great reference with operational settings for each group. Associating the physical and chemical parameters of a unit operation through benchmarking or even an optimal reference of metallurgical recovery and product quality reflects in the reduction of the production costs, optimization of the mineral resource, and guarantee of greater stability in the subsequent processes of the production chain that uses the mineral of interest. Conducting a comprehensive exploratory data analysis to identify which characteristics of the ore are most relevant to the process route, associated with the use of Machine Learning algorithms for grouping the raw material (ore) and associating these with reference variables in the process’ benchmark is a reasonable alternative for the standardization and improvement of mineral processing units. Clustering methods through Decision Tree and K-Means were employed, associated with algorithms based on the theory of benchmarking, with criteria defined by the process team in order to reference the best adjustments for processing the ore piles of each cluster. A clean user interface was created to obtain the outputs of the created algorithm. The results were measured through the average time of adjustment and stabilization of the process after a new pile of homogenized ore enters the plant, as well as the average time needed to achieve the best processing result. Direct gains from the metallurgical recovery of the process were also measured. The results were promising, with a reduction in the adjustment time and stabilization when starting the processing of a new ore pile, as well as reaching the benchmark. Also noteworthy are the gains in metallurgical recovery, which reflect a significant saving in ore consumption and a consequent reduction in production costs, hence a more rational use of the tailings dams and life optimization of the mineral deposit.

Keywords: mineral clustering, machine learning, process optimization, pyrochlore processing

Procedia PDF Downloads 143
979 Experimental Evaluation of Contact Interface Stiffness and Damping to Sustain Transients and Resonances

Authors: Krystof Kryniski, Asa Kassman Rudolphi, Su Zhao, Per Lindholm

Abstract:

ABB offers range of turbochargers from 500 kW to 80+ MW diesel and gas engines. Those operate on ships, power stations, generator-sets, diesel locomotives and large, off-highway vehicles. The units need to sustain harsh operating conditions, exposure to high speeds, temperatures and varying loads. They are expected to work at over-critical speeds damping effectively any transients and encountered resonances. Components are often connected via friction joints. Designs of those interfaces need to account for surface roughness, texture, pre-stress, etc. to sustain against fretting fatigue. The experience from field contributed with valuable input on components performance in hash sea environment and their exposure to high temperature, speed and load conditions. Study of tribological interactions of oxide formations provided an insight into dynamic activities occurring between the surfaces. Oxidation was recognized as the dominant factor of a wear. Microscopic inspections of fatigue cracks on turbine indicated insufficient damping and unrestrained structural stress leading to catastrophic failure, if not prevented in time. The contact interface exhibits strongly non-linear mechanism and to describe it the piecewise approach was used. Set of samples representing the combinations of materials, texture, surface and heat treatment were tested on a friction rig under range of loads, frequencies and excitation amplitudes. Developed numerical technique extracted the friction coefficient, tangential contact stiffness and damping. Vast amount of experimental data was processed with the multi-harmonics balance (MHB) method to categorize the components subjected to the periodic excitations. At the pre-defined excitation level both force and displacement formed semi-elliptical hysteresis curves having the same area and secant as the actual ones. By cross-correlating the terms remaining in the phase and out of the phase, respectively it was possible to separate an elastic energy from dissipation and derive the stiffness and damping characteristics.

Keywords: contact interface, fatigue, rotor-dynamics, torsional resonances

Procedia PDF Downloads 375
978 Earth Flat Roofs

Authors: Raúl García de la Cruz

Abstract:

In the state of Hidalgo and to the vicinity to the state of Mexico, there is a network of people who also share a valley bordered by hills with agave landscape of cacti and shared a bond of building traditions inherited from pre-Hispanic times and according to their material resources, habits and needs have been adapted in time. Weather has played an important role in the way buildings and roofs are constructed. Throughout the centuries, the population has developed very sophisticated building techniques like the flat roof, made out of a layer of earth; that is usually identified as belonging to architecture of the desert, but it can also be found in other climates, such as semi-arid and even template climates. It is an example of a constructive logic applied efficiently to various cultures proving its thermal isolation. So far it has done a review and analysis of the use of the roof in different areas, from pre-Hispanic architecture to traditional Moroccan architecture , finding great similarities in the elements of the system to be incorporated into the contemporary architecture. The rescue of a lore that dissolves with the changing environment, depends in principle on the links created towards the use of environmental resources as the anchor of the people to retain and preserve a building tradition which has viability deep league with the possibility of obtaining the raw material from the immediate environment. The objective of the research is the documentation of existing earth flat roofs in the state of Hidalgo and Mexico, as evidence of the importance of constructive system and its historical value in the area, considering its environmental, social aspects, also understanding the process of transformation of public housing at the time replaced the traditional techniques for industrial materials on a path towards urbanization. So far it has done a review and analysis of the use of the roof in different areas, from pre-Hispanic architecture to traditional Moroccan architecture, finding great similarities in the elements of the system to be incorporated into the contemporary architecture. The rescue of a lore that dissolves with the changing environment, depends in principle on the links created towards the use of environmental resources as the anchor of the people to retain and preserve a building tradition which has viability deep league with the possibility of obtaining the raw material from the immediate environment.

Keywords: earth roof, low impact building system, sustainable architecture, vernacular architecture

Procedia PDF Downloads 456
977 Design of a Plant to Produce 100,000 MTPY of Green Hydrogen from Brine

Authors: Abdulrazak Jinadu Otaru, Ahmed Almulhim, Hassan Alhassan, Mohammed Sabri

Abstract:

Saudi Arabia is host to a state-owned oil and gas corporation, known as Saudi ARAMCO, that is responsible for the highest emissions of carbon dioxide (CO₂) due to the heavy reliance on fossil fuels as an energy source for various sectors such as transportation, aerospace, manufacturing, and residential use. Unfortunately, the detrimental consequences of CO₂ emissions include escalating temperatures in the Middle East region, posing significant obstacles in terms of food security and water scarcity for the Kingdom of Saudi Arabia. As part of the Saudi Vision 2030 initiative, which aims to reduce the country's reliance on fossil fuels by 50 %, this study focuses on designing a plant that will produce approximately 100,000 metric tons per year (MTPY) of green hydrogen (H₂) using brine as the primary feedstock. The proposed facility incorporates a double electrolytic technology that first separates brine or sodium chloride (NaCl) into sodium hydroxide, hydrogen gas, and chlorine gas. The sodium hydroxide is then used as an electrolyte in the splitting of water molecules through the supply of electrical energy in a second-stage electrolyser to produce green hydrogen. The study encompasses a comprehensive analysis of process descriptions and flow diagrams, as well as materials and energy balances. It also includes equipment design and specification, cost analysis, and considerations for safety and environmental impact. The design capitalizes on the abundant brine supply, a byproduct of the world's largest desalination plant located in Al Jubail, Saudi Arabia. Additionally, the design incorporates the use of available renewable energy sources, such as solar and wind power, to power the proposed plant. This approach not only helps reduce carbon emissions but also aligns with Saudi Arabia's energy transition policy. Furthermore, it supports the United Nations Sustainable Development Goals on Sustainable Cities and Communities (Goal 11) and Climate Action (Goal 13), benefiting not only Saudi Arabia but also other countries in the Middle East.

Keywords: plant design, electrolysis, brine, sodium hydroxide, chlorine gas, green hydrogen

Procedia PDF Downloads 48
976 Nursing Students’ Opinions about Theoretical Lessons and Clinical Area: A Survey in a Nursing Department

Authors: Ergin Toros, Manar Aslan

Abstract:

This study was planned as a descriptive study in order to learn the opinions of the students who are studying in nursing undergraduate program about their theoretical/practical lessons and departments. The education in the undergraduate nursing programs has great importance because it contains the knowledge and skills to prepare student nurses to the clinic in the future. In order to provide quality-nursing services in the future, the quality of nursing education should be measured, and opinions of student nurses about education should be taken. The research population was composed of students educated in a university with 1-4 years of theoretical and clinical education (N=550), and the sample was composed of 460 students that accepted to take part in the study. It was reached to 83.6% of target population. Data collected through a survey developed by the researchers. Survey consists of 48 questions about sociodemographic characteristics (9 questions), theoretical courses (9 questions), laboratory applications (7 questions), clinical education (14 questions) and services provided by the faculty (9 questions). It was determined that 83.3% of the nursing students found the nursing profession to be suitable for them, 53% of them selected nursing because of easy job opportunity, and 48.9% of them stayed in state dormitory. Regarding the theoretical courses, 84.6% of the students were determined to agree that the question ‘Course schedule is prepared before the course and published on the university web page.’ 28.7% of them were determined to do not agree that the question ‘Feedback is given to students about the assignments they prepare.’. It has been determined that 41,5% of the students agreed that ‘The time allocated to laboratory applications is sufficient.’ Students said that physical conditions in laboratory (41,5%), and the materials used are insufficient (44.6%), and ‘The number of students in the group is not appropriate for laboratory applications.’ (45.2%). 71.3% of the students think that the nurses view in the clinics the students as a tool to remove the workload, 40.7% of them reported that nurses in the clinic area did not help through the purposes of the course, 39.6% of them said that nurses' communication with students is not good. 37.8% of students stated that nurses did not provide orientation to students, 37.2% of them think that nurses are not role models for students. 53.7% of the students stated that the incentive and support for the student exchange program were insufficient., %48 of the students think that career planning services, %47.2 security services,%45.4 the advisor spent time with students are not enough. It has been determined that nursing students are most disturbed by the approach of the nurses in the clinical area within the undergraduate education program. The clinical area education which is considered as an integral part of nursing education is important and affect to student satisfaction.

Keywords: nursing education, student, clinical area, opinion

Procedia PDF Downloads 176
975 Electrocatalytic Properties of Ru-Pd Bimetal Quantum Dots/TiO₂ Nanotube Arrays Electrodes Composites with Double Schottky Junctions

Authors: Shiying Fan, Xinyong Li

Abstract:

The development of highly efficient multifunctional catalytic materials towards HER, ORR and Photo-fuel cell applications in terms of combined electrochemical and photo-electrochemical principles have currently confronted with dire challenges. In this study, novel palladium (Pd) and ruthenium (Ru) Bimetal Quantum Dots (BQDs) co-anchored on Titania nanotube (NTs) arrays electrodes have been successfully constructed by facial two-step electrochemical strategy. Double Schottky junctions with superior performance in electrocatalytic (EC) hydrogen generations and solar fuel cell energy conversions (PE) have been found. Various physicochemical techniques including UV-vis spectroscopy, TEM/EDX/HRTEM, SPV/TRV and electro-chemical strategy including EIS, C-V, I-V, and I-T, etc. were chronically utilized to systematically characterize the crystal-, electronic and micro-interfacial structures of the composites with double Schottky junction, respectively. The characterizations have implied that the marvelous enhancement of separation efficiency of electron-hole pairs generations is mainly caused by the Schottky-barriers within the nanocomposites, which would greatly facilitate the interfacial charge transfer for H₂ generations and solar fuel cell energy conversions. Moreover, the DFT calculations clearly indicated that the oriented growth of Ru and Pd bimetal atoms at the anatase (101) surface is mainly driven by the interaction between Ru/Pd and surface atoms, and the most active site for bimetal Ru and Pd adatoms on the perfect TiO₂ (101) surface is the 2cO-6cTi-3cO bridge sites and the 2cO-bridge sites with the highest adsorption energy of 9.17 eV. Furthermore, the electronic calculations show that in the nanocomposites, the number of impurity (i.e., co-anchored Ru-Pd BQDs) energy levels near Fermi surface increased and some were overlapped with original energy level, promoting electron energy transition and reduces the band gap. Therefore, this work shall provide a deeper insight for the molecular design of Bimetal Quantum Dots (BQDs) assembled onto Tatiana NTs composites with superior performance for electrocatalytic hydrogen productions and solar fuel cell energy conversions (PE) simultaneously.

Keywords: eletrocatalytic, Ru-Pd bimetallic quantum dots, titania nanotube arrays, double Schottky junctions, hydrogen production

Procedia PDF Downloads 143
974 Proposing Smart Clothing for Addressing Criminal Acts Against Women in South Africa

Authors: Anne Mastamet-Mason

Abstract:

Crimes against women is a global concern, and South Africa, in particular, is in a dilemma of dealing with constant criminal acts that face the country. Debates on violence against women in South Africa cannot be overemphasised any longer as crimes continue to rise year by year. The recent death of a university student at the University of Cape Town, as well as many other cases, continues to strengthen the need to find solutions from all the spheres of South African society. The advanced textiles market contains a high number and variety of technologies, many of which have protected status and constitute a relatively small portion of the textiles used for the consumer market. Examples of advanced textiles include nanomaterials, such as silver, titanium dioxide and zinc oxide, designed to create an anti-microbial and self-cleaning layer on top of the fibers, thereby reducing body smell and soiling. Smart textiles propose materials and fabrics versatile and adaptive to different situations and functions. Integrating textiles and computing technologies offer an opportunity to come up with differentiated characteristics and functionality. This paper presents a proposal to design a smart camisole/Yoga sports brazier and a smart Yoga sports pant garment to be worn by women while alone and while in purported danger zones. The smart garments are to be worn under normal clothing and cannot be detected or seen, or suspected by perpetrators. The garments are imbued with devices to sense any physical aggression and any abnormal or accelerated heartbeat that may be exhibited by the victim of violence. The signals created during the attack can be transmitted to the police and family members who own a mobile application system that accepts signals emitted. The signals direct the receiver to the exact location of the offence, and the victim can be rescued before major violations are committed. The design of the Yoga sports garments will be done by Professor Mason, who is a fashion designer by profession, while the mobile phone application system will be developed by Mr. Amos Yegon, who is an independent software developer.

Keywords: smart clothing, wearable technology, south africa, 4th industrial revolution

Procedia PDF Downloads 207
973 Explosion Mechanics of Aluminum Plates Subjected to the Combined Effect of Blast Wave and Fragment Impact Loading: A Multicase Computational Modeling Study

Authors: Atoui Oussama, Maazoun Azer, Belkassem Bachir, Pyl Lincy, Lecompte David

Abstract:

For many decades, researchers have been focused on understanding the dynamic behavior of different structures and materials subjected to fragment impact or blast loads separately. The explosion mechanics, as well as the impact physics studies dealing with the numerical modeling of the response of protective structures under the synergistic effect of a blast wave and the impact of fragments, are quite limited in the literature. This article numerically evaluates the nonlinear dynamic behavior and damage mechanisms of Aluminum plates EN AW-1050A- H24 under different combined loading scenarios varied by the sequence of the applied loads using the commercial software LS-DYNA. For one hand, with respect to the terminal ballistic field investigations, a Lagrangian (LAG) formulation is used to evaluate the different failure modes of the target material in case of a fragment impact. On the other hand, with respect to the blast field analysis, an Arbitrary Lagrangian-Eulerian (ALE) formulation is considered to study the fluid-structure interaction (FSI) of the shock wave and the plate in case of a blast loading. Four different loading scenarios are considered: (1) only blast loading, (2) only fragment impact, (3) blast loading followed by a fragment impact and (4) a fragment impact followed by blast loading. From the numerical results, it was observed that when the impact load is applied to the plate prior to the blast load, it suffers more severe damage due to the hole enlargement phenomenon and the effects of crack propagation on the circumference of the damaged zone. Moreover, it was found that the hole from the fragment impact loading was enlarged to about three times in diameter as compared to the diameter of the projectile. The validation of the proposed computational model is based in part on previous experimental data obtained by the authors and in the other part on experimental data obtained from the literature. A good correspondence between the numerical and experimental results is found.

Keywords: computational analysis, combined loading, explosion mechanics, hole enlargement phenomenon, impact physics, synergistic effect, terminal ballistic

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972 Possible Endocrinal and Liver Enzymes Toxicities Associated with Long Term Exposure to Benzene in Saudi Arabia

Authors: Faizah Asiri, Mohammed Fathy, Saeed Alghamdi, Nahlah Ayoub, Faisal Asiri

Abstract:

Background: - The strategies for this study were based on the toxic effect of long-term inhalation of Benzene on hormones and liver enzymes and various parameters related to it. The following databases were searched: benzene, hepatotoxic, benzene metabolism, hormones, testosterone, hemotoxic, and prolonged exposure. A systematic strategy is designed to search the literature that links benzene with the multiplicity and different types of intoxication or the medical abbreviations of diseases relevant to benzene exposure. Evidence suggests that getting rid of inhaled gasoline is by exhalation. Absorbed benzene is metabolized by giving phenolic acid as well as meconic acid, followed by urinary excretion of conjugate sulfates and glucuronides. Materials and Methods :- This work was conducted in the Al-Khadra laboratory in Taif 2020/2021 and aimed to measure some of the possible endocrinal and liver toxicities associated with benzene's long-term exposure in Saudi Arabia at the station workers who are considered the most exposed category to gasoline. One hundred ten station workers were included in this study. They were divided into four patient groups according to the chronic exposure rate to benzene, one control group, and three other groups of exposures. As follows: patient Group 1 (controlled group), patient Group 2 (exposed less than 1y), patient Group 3 (exposed 1-5 y), patient Group 4 (more than 5). Each group is compared with blood sample parameters (ALT, FSH and Testosterone, TSH). Blood samples were drawn from the participants, and statistical tests were performed. Significant change (p≤0.05) was examined compared to the control group. Workers' exposure to benzene led to a significant change in hematological, hormonal, and hepatic factors compared to the control group. Results:- The results obtained a relationship between long-term exposure to benzene and a decrease in the level of testosterone and FSH hormones, including that it poses a toxic risk in the long term (p≤0.05) when compared to the control. We obtained results confirming that there is no significant coloration between years of exposure and TSH level (p≤0.05) when compared to the control. Conclusion:- We conclude that some hormones and liver enzymes are affected by chronic doses of benzene through inhalation after our study was on the group most exposed to benzene, which is gas station workers.

Keywords: toxicities, benzene, hormones, station workers

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