Search results for: escape room
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1496

Search results for: escape room

416 Load Transfer of Steel Pipe Piles in Warming Permafrost

Authors: S. Amirhossein Tabatabaei, Abdulghader A. Aldaeef, Mohammad T. Rayhani

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As the permafrost continues to melt in the northern regions due to global warming, a soil-water mixture is left behind with drastically lower strength; a phenomenon that directly impacts the resilience of existing structures and infrastructure systems. The frozen soil-structure interaction, which in ice-poor soils is controlled by both interface shear and ice-bonding, changes its nature into a sole frictional state. Adfreeze, the controlling mechanism in frozen soil-structure interaction, diminishes as the ground temperature approaches zero. The main purpose of this paper is to capture the altered behaviour of frozen interface with respect to rising temperature, especially near melting states. A series of pull-out tests are conducted on model piles inside a cold room to study how the strength parameters are influenced by the phase change in ice-poor soils. Steel model piles, embedded in artificially frozen cohesionless soil, are subjected to both sustained pull-out forces and constant rates of displacement to observe the creep behaviour and acquire load-deformation curves, respectively. Temperature, as the main variable of interest, is increased from a lower limit of -10°C up to the point of melting. During different stages of the temperature rise, both skin deformations and temperatures are recorded at various depths along the pile shaft. Significant reduction of pullout capacity and accelerated creep behaviour is found to be the primary consequences of rising temperature. By investigating the different pull-out capacities and deformations measured during step-wise temperature change, characteristics of the transition from frozen to unfrozen soil-structure interaction are studied.

Keywords: Adfreeze, frozen soil-structure interface, ice-poor soils, pull-out capacity, warming permafrost

Procedia PDF Downloads 111
415 Evaluation of the Shelf Life of Horsetail Stems Stored in Ecological Packaging

Authors: Rosana Goncalves Das Dores, Maira Fonseca, Fernando Finger, Vicente Casali

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Equisetum hyemale L. (horsetail, Equisetaceae) is a medicinal plant used and commercialized in simple paper bags or non-ecological packaging in Brazil. The aim of this work was to evaluate the relation between the bioactive compounds of horsetail stems stored in ecological packages (multi-ply paper sacks) at room temperature. Stems in primary and secondary stage were harvested from an organic estate, on December 2016, selected, measured (length from the soil to the apex (cm), stem diameter at ground level (DGL mm) and breast height (DBH mm) and cut into 10 cm. For the post-harvest evaluations, stems were stored in multi-ply paper sacks and evaluated daily to the respiratory rate, fresh weight loss, pH, presence of fungi / mold, phenolic compounds and antioxidant activity. The analyses were done with four replicates, over time (regression) and compared at 1% significance (Tukey test). The measured heights were 103.7 cm and 143.5 cm, DGL was 2.5mm and 8.4 mm and DBH of 2.59 and 6.15 mm, respectively for primary and secondary stems stage. At both stages of development, in storage in multi-ply paper sacks, the greatest mass loss occurred at 48 h, decaying up to 120 hours, stabilizing at 192 hours. The peak respiratory rate increase occurred in 24 hours, coinciding with a change in pH (temperature and mean humidity was 23.5°C and 55%). No fungi or mold were detected, however, there was loss of color of the stems. The average yields of ethanolic extracts were equivalent (approximately 30%). Phenolic compounds and antioxidant activity were higher in secondary stems stage in up to 120 hours (AATt0 = 20%, AATt30 = 45%), decreasing at the end of the experiment (240 hours). The packaging used allows the commercialization of fresh stems of Equisetum for up to five days.

Keywords: paper sacks, phenolic content, antioxidant activity, medicinal plants, post-harvest, ecological packages, Equisetum

Procedia PDF Downloads 166
414 Plasma Pretreatment for Improving the Durability of Antibacterial Activity of Cotton Using ZnO Nanoparticles

Authors: Sheila Shahidi, Hootan Rezaee, Abosaeed Rashidi, Mahmood Ghoranneviss

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Plasma treatment has an explosive increase in interest and use in industrial applications as for example in medical, biomedical, automobile, electronics, semiconductor and textile industry. A lot of intensive basic research has been performed in the last decade in the field of textiles along with technical textiles. Textile manufacturers and end-users alike have been searching for ways to improve the surface properties of natural and man-made fibers. Specifically, there is a need to improve adhesion and wettability. Functional groups may be introduced onto the fiber surface by using gas plasma treatments, improving fiber surface properties without affecting the fiber’s bulk properties. In this research work, ZnO nanoparticles (ZnO-NPs) were insitue synthesized by sonochemical method at room temperature on both untreated and plasma pretreated cotton woven fabric. Oxygen and nitrogen plasmas were used for pre-functionalization of cotton fabric. And the effect of oxygen and nitrogen pre-functionalization on adhesion properties between ZnO nanoparticles and cotton surface were studied. The results show that nanoparticles with average sizes of 20-100 nm with different morphologies have been created on the surface of samples. Synthesis of ZnO-NPs was varied in the morphological transformation by changes in zinc acetate dehydrate concentration. Characterizations were carried out using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Inductive coupled plasma (ICP) and Spectrophotometery. The antibacterial activities of the fabrics were assessed semi-quantitatively by the colonies count method. The results show that the finished fabric demonstrated significant antibacterial activity against S. aureus in antibacterial test. The wash fastness of both untreated and plasma pretreated samples after 30 times of washing was investigated. The results showed that the parameters of plasma reactor plays very important role for improving the antibacterial durability.

Keywords: antibacterial activity, cotton, fabric, nanoparticles, plasma

Procedia PDF Downloads 537
413 Diversity of Dermatophytes and Keratinophilic Fungi from Inernational Tourist Spots, City of Taj Mahal

Authors: Harison Masih, Jyotsna Kiran Peter, Sundara Singh, Geetha Singh

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The present investigation deals with diversity of dermatophytes and keratinophilic fungi from different tourist spots such as Agra Fort, Akbar tomb, It-Mat-Ud-Daulah, Mariam tomb, Radha Swami Bagh, and Taj Mahal of Agra City. These fungi are medically important which causes various infections and diseases in humans and animals. The main reservoir of these pathogens are the keratinous substances that increases due to birds and animal activities in the vicinity of monuments, where thousands (5413266) annual visitors from all over the world are visiting. The soil samples were subjected to isolate the pathogenic fungi through bait technique (buffalo skin, chicken feathers, human hair and goat tail hair). Baits were spread over the soil samples and incubated at room temperature for 30-35 days and pure culture isolates were maintained in SDA medium, stored at 4°C. Highest number of visitors were (3906453) from Taj Mahal, minimum 10785 at Mariam tomb annually, the total 271 isolates were encountered from soil samples out of these 18 genera and 38 species were found in different season. Highest incidence was 4.79% frequency shown by Chrysosporium keratinophilum while least 738% frequency occurrence by Trichophyton simii in soil samples. From the present study it was concluded that the incidence of pathogenic fungal isolates were the common in tourists soil that are etiological agents of superficial mycosis. Thus, both human and animal activity seemed to play an important role in occurrence and distribution of keratinophilic and related dermatophytes at various tourist places of Agra city.

Keywords: dermatophytic fungal diversity, bait technique, visitors at tourist spots, human and animal activities, soil samples

Procedia PDF Downloads 487
412 Job Stress Among the Nurses of the Emergency Department of Selected Saudi Hospital

Authors: Mahmoud Abdel Hameed Shahin

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Job demands that are incompatible with an employee's skills, resources, or needs cause unpleasant emotional and physical reactions known as job stress. Nurses offer care in hospital emergency rooms all around the world, and since they operate in such a dynamic and unpredictable setting, they are constantly under pressure. It has been discovered that job stress has harmful impacts on nurses' health as well as their capacity to handle the demands of their jobs. The purpose of this study was to evaluate the level of job stress experienced by the emergency department nurses at King Fahad Specialist Hospital in Buraidah City, Saudi Arabia. In October 2021, a cross-sectional descriptive study was conducted. 80 nurses were conveniently selected for the study, the bulk of them worked at King Fahad Specialist Hospital's emergency department. An electronic questionnaire with a sociodemographic data sheet and a job stress scale was given to the participating nurses after ethical approval was received from the Ministry of Health's representative bodies. Using SPSS Version 26, both descriptive and inferential statistics were employed to analyze and tabulate the acquired data. According to the findings, the factors that contributed to the most job stress in the clinical setting were having an excessive amount of work to do and working under arbitrary deadlines, whereas the factors that contributed to the least stress were receiving the proper recognition or rewards for good work. In the emergency room of King Fahad Specialist Hospital, nurses had a moderate level of stress (M=3.32 ± 0.567/5). Based on their experience, emergency nurses' levels of job stress varied greatly, with nurses with less than a year of experience notably experiencing the lowest levels of job stress. The amount of job stress did not differ significantly based on the emergency nurses' age, nationality, gender, marital status, position, or level of education. The causes and impact of stress on emergency nurses should be identified and alleviated by hospitals through the implementation of interventional programs.

Keywords: emergency nurses, job pressure, Qassim, Saudi Arabia, job stress

Procedia PDF Downloads 189
411 The Effect of Visual Access to Greenspace and Urban Space on a False Memory Learning Task

Authors: Bryony Pound

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This study investigated how views of green or urban space affect learning performance. It provides evidence of the value of visual access to greenspace in work and learning environments, and builds on the extensive research into the cognitive and learning-related benefits of access to green and natural spaces, particularly in learning environments. It demonstrates that benefits of visual access to natural spaces whilst learning can produce statistically significant faster responses than those facing urban views after only 5 minutes. The primary hypothesis of this research was that a greenspace view would improve short-term learning. Participants were randomly assigned to either a view of parkland or of urban buildings from the same room. They completed a psychological test of two stages. The first stage consisted of a presentation of words from eight different categories (four manmade and four natural). Following this a 2.5 minute break was given; participants were not prompted to look out of the window, but all were observed doing so. The second stage of the test involved a word recognition/false memory test of three types. Type 1 was presented words from each category; Type 2 was non-presented words from those same categories; and Type 3 was non-presented words from different categories. Participants were asked to respond with whether they thought they had seen the words before or not. Accuracy of responses and reaction times were recorded. The key finding was that reaction times for Type 2 words (highest difficulty) were significantly different between urban and green view conditions. Those with an urban view had slower reaction times for these words, so a view of greenspace resulted in better information retrieval for word and false memory recognition. Importantly, this difference was found after only 5 minutes of exposure to either view, during winter, and with a sample size of only 26. Greenspace views improve performance in a learning task. This provides a case for better visual access to greenspace in work and learning environments.

Keywords: benefits, greenspace, learning, restoration

Procedia PDF Downloads 127
410 Driving and Hindering Forces for the Care of Older People: experiences of Brazilian Family Caregivers

Authors: Adriane Amend, Leidiene Ferreira Santos, Daniella Pires Nunes

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The experience of assuming or caring for older persons dependents by relatives is a complex task that encompasses or affective involvement, the demand for technical activities and or psychological support. It would be necessary to understand the situations related to the caregiver, the person and the environment, which help the family difficulty, as a caregiver to lead this role. Objective: To identify the forces that drive and restrict the care process of family caregivers of the older adults. Method: Descriptive and exploratory research, with a qualitative approach, which has as a reference the Force Field Theory. Five family caregivers of older adult’s dependents residing in the city of Palmas, Tocantins, Brazil will participate. The data were collected from December 2021 to February 2022, through a semi-structured individual interview, and submitted to content analysis. Results: As forces that drive or process of caring for family caregivers were: the account of compassionate attitudes and patience of the caregiver (I); to the collaboration of the other person to the care and to the body structure of the same (Other); and the supports of other people not cared for and structural, such as adaptations in the room, read and bathroom, as in the presence of air conditioners (Environment). Among the restrictive forces of care we mention difficulties in delegating care to another person, or stress of care and other personal demands (I); imposition of the older person about care and e a transfer from bed to hip (Other); e lack of accessibility of the house and absence of air conditioning and hospital bed (Environment). Conclusion: The results show that there are driving forces with the caregiver's attitude and feelings, a bond as an idol and support for the caregiver and the environment. On the other hand, conflicting ties, absence of physical structure and daily and continuous care shifts, can significantly compromise well-being or the cycle of older adult, caregiver and care.

Keywords: caregivers, frail elderly, perception, geriatric nursing

Procedia PDF Downloads 94
409 Analysis of the Physical Behavior of Library Users in Reading Rooms through GIS: A Case Study of the Central Library of Tehran University

Authors: Roya Pournaghi

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Measuring the extent of daily use of the libraries study space is of utmost significance in order to develop, re-organize and maintain the efficiency of the study space. The current study aimed to employ GIS in analyzing the study halls space of the document center and central library of Tehran University and determine the extent of use of the study chairs and desks by the students-intended users. This combination of survey methods - descriptive design system. In order to collect the required data and a description of the method, To implement and entering data into ArcGIS software. It also analyzes the data and displays the results on the library floor map design method were used. And spatial database design and plan has been done at the Central Library of Tehran University through the amount of space used by members of the Library and Information halls plans. Results showed that Biruni's hall is allocated the highest occupancy rate to tables and chairs compared to other halls. In the Hall of Science and Technology, with an average occupancy rate of 0.39 in the tables represents the lowest users and Rashid al-Dins hall, and Science and Technology’s hall with an average occupancy rate (0.40) represents the lowest users of seats. In this study, the comparison of the space is occupied at different period as a study’s hall in the morning, evenings, afternoons, and several months was performed through GIS. This system analyzed the space relationship effectively and efficiently. The output of this study can be used by administrators and librarians to determine the exact amount of using the Equipment of study halls and librarians can use the output map to design more efficient space at the library.

Keywords: geospatial information system, spatial analysis, reading room, academic libraries, library’s user, central library of Tehran university

Procedia PDF Downloads 235
408 Improving the Corrosion Resistance of Magnesium by Application of TiO₂-MgO Coatings

Authors: Eric Noe Hernandez Rodriguez, Cristian Esneider Penuela Cruz

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Magnesium is a biocompatible and biodegradable material that has gained increased interest for application in resorbable orthopedic implants. However, to date, much research is being conducted to overcome the main disadvantage: its low corrosion resistance. In this work, we report our findings on the development and application of TiO₂-MgO coatings to improve and modulate the corrosion resistance of magnesium pieces. The plasma electrolytic oxidation (PEO) technique was employed to obtain the TiO₂-MgO coatings. The effect of the experimental parameters on the modulation of the TiO₂:MgO ratio was investigated. The most critical parameters were the chemical composition of the precursor electrolytic solution and the current density. According to scanning electron microscopy (SEM) observations, the coatings were porous; however, they become more compact as the current density increases. XRD measurements showed that the coatings are formed by a composite consisting of TiO₂ and MgO oxides, whose ratio can be changed by the experimental conditions. TiO₂ had the anatase crystalline structure, while the MgO had the FCC crystalline structure. The corrosion resistance was evaluated through the corrosion current (Icorr) measured at room temperature by the polarization technique (Tafel). For doing it, Hank's solution was used in order to simulate the body fluids. Also, immersion tests were conducted. Tafel curves showed an improvement of the corrosion resistance at some coated magnesium pieces in contrast to control pieces (uncoated). Corrosion currents were lower, and the corrosion potential changed to positive values. It was observed that the experimental parameters allowed to modulate the protective capacity of the coatings by changing the TiO₂:MgO ratio. Coatings with a higher content of TiO₂ (measured by energy dispersive spectroscopy) showed higher corrosion resistance. Results showed that TiO₂-MgO coatings can be successfully applied to improve the corrosion resistance of Mg pieces in simulated body fluid; even more, the corrosion resistance can be tuned by changing the TiO₂:MgO ratio.

Keywords: biomaterials, PEO, corrosion resistance, magnesium

Procedia PDF Downloads 104
407 Near Ambient Pressure Photoelectron Spectroscopy Studies of CO Oxidation on Spinel Co3O4 Surfaces: Electronic Structure and Mechanistic Aspects of Wet and Dry CO Oxidation

Authors: Ruchi Jain, Chinnakonda S. Gopinath

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The CO oxidation is a primary reaction in heterogeneous catalysis due to its potential to overcome the air pollution caused by various reasons. Indeed, in the study of sustainable catalysis, the role played by water is very important. The present work is focused on studying the effect of moisture on the sustainability of Co3O4 NR catalyst for CO oxidation reaction at ambient temperature. The catalytic activity, electronic structure and the mechanistic aspects of spinel Co3O4 nanorod surfaces have been explored in dry and wet atmosphere by near-ambient pressure photoelectron spectroscopic techniques (NAP-PES) with conventional x-ray (Al kα) and ultraviolet sources (He-I).Comparative NAPPES studies have been employed to understand the elucidation of the catalytic reaction pathway and the evolution of various surface species. The presence of water with CO+O2 plummet the catalytic activity due to the change in electronic nature from predominantly oxidic (without water in the feed) to few intermediates covered Co3O4 surface. However, ≥ 375 K Co3O4 surface recovers and regain oxidation activity, at least partially, even in the presence of water. Above mentioned observations are fully supported by the changes observed in the work function of Co3O4 in the presence of wet (H2O+CO+O2) compared to dry (CO+O2) conditions. Various type of surface species, such as CO(ads), carbonate, formate, are found to be on the catalyst surface depending on the reaction conditions. Under dry condition, CO couples with labile O atoms to form CO2, however under wet conditions it also interacts with surface OH groups results in the formation carbonate and formate intermediate. The carbonate acts at reaction inhibitor at room temperature, however proves as active intermediate at temperature 375 K or above. On the other hand, formate has proved to be reaction spectator due to its high stability. The intrinsic role of these species to suppress the oxidation has been demonstrated through a possible reaction mechanism under different reaction conditions.

Keywords: heterogeneous catalysis, surface chemistry, photoelectron spectroscopy, ambient oxidation

Procedia PDF Downloads 255
406 Standard Protocol Selection for Acquisition of Breast Thermogram in Perspective of Early Breast Cancer Detection

Authors: Mrinal Kanti Bhowmik, Usha Rani Gogoi Jr., Anjan Kumar Ghosh, Debotosh Bhattacharjee

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In the last few decades, breast thermography has achieved an average sensitivity and specificity of 90% for breast tumor detection. Breast thermography is a non-invasive, cost-effective, painless and radiation-free breast imaging modality which makes a significant contribution to the evaluation and diagnosis of patients, suspected of having breast cancer. An abnormal breast thermogram may indicate significant biological risk for the existence or the development of breast tumors. Breast thermography can detect a breast tumor, when the tumor is in its early stage or when the tumor is in a dense breast. The infrared breast thermography is very sensitive to environmental changes for which acquisition of breast thermography should be performed under strictly controlled conditions by undergoing some standard protocols. Several factors like air, temperature, humidity, etc. are there to be considered for characterizing thermal images as an imperative tool for detecting breast cancer. A detailed study of various breast thermogram acquisition protocols adopted by different researchers in their research work is provided here in this paper. After going through a rigorous study of different breast thermogram acquisition protocols, a new standard breast thermography acquisition setup is proposed here in this paper for proper and accurate capturing of the breast thermograms. The proposed breast thermogram acquisition setup is being built in the Radiology Department, Agartala Government Medical College (AGMC), Govt. of Tripura, Tripura, India. The breast thermograms are captured using FLIR T650sc thermal camera with the thermal sensitivity of 20 mK at 30 degree C. The paper is an attempt to highlight the importance of different critical parameters of breast thermography like different thermography views, patient preparation protocols, acquisition room requirements, acquisition system requirements, etc. This paper makes an important contribution by providing a detailed survey and a new efficient approach on breast thermogram capturing.

Keywords: acquisition protocol, breast cancer, breast thermography, infrared thermography

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405 A Perspective on Emergency Care of Gunshot Injuries in Northern Taiwan

Authors: Liong-Rung Liu, Yu-Hui Chiu, Wen-Han Chang

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Firearm injuries are high-energy injuries. The ballistic pathways could cause severe burns or chemical damages to vessels, musculoskeletal or other major organs. The high mortality rate is accompanied by complications such as sepsis. As laws prohibit gun possession, civilian gunshot wounds (GSW) are relatively rare in Taiwan. Our hospital, Mackay Memorial Hospital, located at the center of Taipei city is surrounded by nightclubs and red-light districts. Due to this unique location, our hospital becomes the first-line trauma center managing gunshot victims in Taiwan. To author’s best knowledge, there are few published research articles regarding this unique situation. We hereby analyze the distinct characteristics and length of stay (LOS) of GSW patients in the emergency room (ER) at Mackay Memorial Hospital. A 6-year retrospective analysis of 27 patients treated for GSW injuries from January 2012 to December 2017 was performed. The patients’ records were reviewed for the following analyses, 1) wound position and the correlated clinical presentations; 2) the LOS in ED of patients receiving emergency surgery for major organ or vascular injuries. We found males (96.3%) were injured by guns more often than females (3.7%) in all age groups. The most common injured site was in the extremities. With regards to the ER LOS, the average time were 72.2 ± 34.5 minutes for patients with triage I and 207.4 ± 143.9 minutes for patients with triage II. The ED LOS of patients whose ISS score were more than 15 was 59.9 ± 25.6 minutes, and 179.4 ± 119.8 minutes for patients whose ISS score were between 9 to 15, respectively. Among these 27 patients, 10 patients had emergency surgery and their average ED stay time was 104.5 ± 33.3 minutes. Even more, the average ED stay time could be shortened to 88.8 ± 32.3 minutes in the 5 patients with trauma team activation. In conclusion, trauma team activation in severe GSW patients indeed shortens the ED LOS and might initially improve the quality of patient care. This is the result of better trauma systems, including advances in care from emergency medical services and acute care surgical management.

Keywords: gunshot, length of stay, trauma, mortality

Procedia PDF Downloads 131
404 DFT and SCAPS Analysis of an Efficient Lead-Free Inorganic CsSnI₃ Based Perovskite Solar Cell by Modification of Hole Transporting Layer

Authors: Seyedeh Mozhgan Seyed Talebi, Chih -Hao Lee

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With an abrupt rise in the power conservation efficiency (PCE) of perovskite solar cells (PSCs) within a short span of time, the toxicity of lead was raised as a major hurdle in the path toward their commercialization. In the present research, a systematic investigation of the electrical and optical characteristics of the all-inorganic CsSnI₃ perovskite absorber layer was performed with the Vienna Ab Initio Simulation Package (VASP) using the projector-augmented wave method. The presence of inorganic halide perovskite offers the advantages of enhancing the degradation resistance of the device, reducing the cost of cells, and minimizing the recombination of generated carriers. The simulated standard device using a 1D simulator like solar cell capacitance simulator (SCAPS) version 3308 involves FTO/n-TiO₂/CsSnI₃ Perovskite absorber/Spiro OmeTAD HTL/Au contact layer. The variation in the device design key parameters such as the thickness and defect density of perovskite absorber, hole transport layer and electron transport layer and interfacial defects are examined with their impact on the photovoltaic characteristic parameters. The effect of an increase in operating temperature from 300 K to 400 K on the performance of CsSnI3-based perovskite devices is also investigated. The optimized standard device at room temperature shows the highest PCE of 25.18 % with FF of 75.71 %, Voc of 0.96 V, and Jsc of 34.67 mA/cm². The outcomes and interpretation of different inorganic Cu-based HTLs presence, such as CuSCN, Cu₂O, CuO, CuI, SrCu₂O₂, and CuSbS₂, here represent a critical avenue for the possibility of fabricating high PCE perovskite devices made of stable, low-cost, efficient, safe, and eco-friendly all-inorganic materials like CsSnI₃ perovskite light absorber.

Keywords: CsSnI₃, hole transporting layer (HTL), lead-free perovskite solar cell, SCAPS-1D software

Procedia PDF Downloads 86
403 Analysis and Modeling of the Building’s Facades in Terms of Different Convection Coefficients

Authors: Enes Yasa, Guven Fidan

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Building Simulation tools need to better evaluate convective heat exchanges between external air and wall surfaces. Previous analysis demonstrated the significant effects of convective heat transfer coefficient values on the room energy balance. Some authors have pointed out that large discrepancies observed between widely used building thermal models can be attributed to the different correlations used to calculate or impose the value of the convective heat transfer coefficients. Moreover, numerous researchers have made sensitivity calculations and proved that the choice of Convective Heat Transfer Coefficient values can lead to differences from 20% to 40% of energy demands. The thermal losses to the ambient from a building surface or a roof mounted solar collector represent an important portion of the overall energy balance and depend heavily on the wind induced convection. In an effort to help designers make better use of the available correlations in the literature for the external convection coefficients due to the wind, a critical discussion and a suitable tabulation is presented, on the basis of algebraic form of the coefficients and their dependence upon characteristic length and wind direction, in addition to wind speed. Many research works have been conducted since early eighties focused on the convection heat transfer problems inside buildings. In this context, a Computational Fluid Dynamics (CFD) program has been used to predict external convective heat transfer coefficients at external building surfaces. For the building facades model, effects of wind speed and temperature differences between the surfaces and the external air have been analyzed, showing different heat transfer conditions and coefficients. In order to provide further information on external convective heat transfer coefficients, a numerical work is presented in this paper, using a Computational Fluid Dynamics (CFD) commercial package (CFX) to predict convective heat transfer coefficients at external building surface.

Keywords: CFD in buildings, external convective heat transfer coefficients, building facades, thermal modelling

Procedia PDF Downloads 421
402 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

Procedia PDF Downloads 191
401 Self-Healing Composites of Silicone Rubber

Authors: Anna Strakowska, Marian Zaborski

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This abstract focuses an overview of the methods used to create self-healing silicone composites. It has been shown how incorporating of polyhedral oligomeric silsesquioxanes (POSS) molecules with acid and basic groups to silicone rubber affects the barrier properties, mechanical properties in room and reduced temperature or the influence on relaxation rates of the methylvinylsilicone rubber vulcanizates. Moreover, the presence of silsesquioxanes, their content and the way of composites preparing affect the amount of ionic bonds, as indicated by dynamic - mechanical thermal analysis (DMTA) as well as measurements of equilibrium swelling in toluene. The aim of this work was to study the influence of concentration and different functional groups types selected silsesquioxanes compounds on self-healing effect of silicone rubber and obtain elastomers with good barrier and mechanical properties. Composites based on the methylvinylsilicone rubber with fumed silica as the fillers were manufactured and studied. To obtain self-healing effect various silsesquioxanes with amino and acid groups were used. Every tested sample demonstrated the ability to the self-treatment. The most significant effect was observed for system containing amic-acid isobytyl POSS/ aminopropylisobutyl POSS. Composite with this silsesquioxanes was exhibited the best improvement of gas permeability after heal. Moreover, the addition of POSS with acid and basic groups clearly affects the mechanical properties of the vulcanizates. The most significant effect was observed for the composite material consisting of amic-acid isobytyl POSS / aminoethylaminopropylisobutyl POSS, which tensile strength was even greater than the reference vulcanizate with fumed silica. The development of autonomous self-healing materials could have an enormous influence on all industry branches from motorization to power industry. Self-repairing materials would have a massive impact on lengthening product lifetimes, increasing safety, and lowering product costs by reducing maintenance requirements.

Keywords: barrier properties, mechanical properties, POSS, self-healing composites

Procedia PDF Downloads 341
400 Crystalline Particles Dispersed Cu-Based Metallic Glassy Composites Fabricated by Spark Plasma Sintering

Authors: Sandrine Cardinal, Jean-Marc Pelletier, Guang Xie, Florian Mercier, Florent Delmas

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Bulk metallic glasses exhibit several superior properties, compared to their corresponding crystalline counterpart, such as high strength, high elastic limit or good corrosion resistance. Therefore they can be considered as good candidates for structural applications in many sectors. However, they are generally brittle and do not exhibit plastic deformation at room temperature. These materials are mainly obtained by rapid cooling from a liquid state to prevent crystallization, which limits their size. To overcome these two drawbacks: fragility and limited dimensions, composite metallic glass matrix reinforced by a second phase whose role is to slow crack growth are developed. Concerning the limited size of the pieces, the proposed solution is to get the material from amorphous powders by densifying under load. In this study, Cu50Zr45Al5 bulk metallic glassy matrix composites (MGMCs) containing different volume fraction (Vf) of Zr crystalline particles were manufactured by spark plasma sintering (SPS). Microstructure, thermal stability and mechanical properties of the MGMCs were investigated. Matrix of the composites remains a fully amorphous phase after consolidation at 420°C under 600 MPa. A good dispersion of the particles in the glassy matrix is obtained. Results show that the compressive strength decreases with Vf : 1670 MPa (Vf=0%) to 1300MPa (Vf=30%), the elastic modulus decreases but only slighty respectively 97.3GPa and 94.5 GPa and plasticity is improved from 0 to 4%. Fractographic investigation indicates a good bonding between amorphous and crystalline particles. In conclusion, present study has demonstrated that SPS method is useful for the synthesis of the bulk glassy composites. Large controlled microstructure specimens with interesting ductility can be obtained compared with others methods.

Keywords: composite, mechanical properties, metallic glasses, spark plasma sintering

Procedia PDF Downloads 279
399 An Efficient Robot Navigation Model in a Multi-Target Domain amidst Static and Dynamic Obstacles

Authors: Michael Ayomoh, Adriaan Roux, Oyindamola Omotuyi

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This paper presents an efficient robot navigation model in a multi-target domain amidst static and dynamic workspace obstacles. The problem is that of developing an optimal algorithm to minimize the total travel time of a robot as it visits all target points within its task domain amidst unknown workspace obstacles and finally return to its initial position. In solving this problem, a classical algorithm was first developed to compute the optimal number of paths to be travelled by the robot amidst the network of paths. The principle of shortest distance between robot and targets was used to compute the target point visitation order amidst workspace obstacles. Algorithm premised on the standard polar coordinate system was developed to determine the length of obstacles encountered by the robot hence giving room for a geometrical estimation of the total surface area occupied by the obstacle especially when classified as a relevant obstacle i.e. obstacle that lies in between a robot and its potential visitation point. A stochastic model was developed and used to estimate the likelihood of a dynamic obstacle bumping into the robot’s navigation path and finally, the navigation/obstacle avoidance algorithm was hinged on the hybrid virtual force field (HVFF) method. Significant modelling constraints herein include the choice of navigation path to selected target points, the possible presence of static obstacles along a desired navigation path and the likelihood of encountering a dynamic obstacle along the robot’s path and the chances of it remaining at this position as a static obstacle hence resulting in a case of re-routing after routing. The proposed algorithm demonstrated a high potential for optimal solution in terms of efficiency and effectiveness.

Keywords: multi-target, mobile robot, optimal path, static obstacles, dynamic obstacles

Procedia PDF Downloads 281
398 Muscle Neurotrophins Family Response to Resistance Exercise

Authors: Rasoul Eslami, Reza Gharakhanlou

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NT-4/5 and TrkB have been proposed to be involved in the coordinated adaptations of the neuromuscular system to elevated level of activity. Despite the persistence of this neurotrophin and its receptor expression in adult skeletal muscle, little attention has been paid to the functional significance of this complex in the mature neuromuscular system. Therefore, the purpose of this research was to study the effect of one session of resistance exercise on mRNA expression of NT4/5 and TrkB proteins in slow and fast muscles of Wistar Rats. Male Wistar rats (10 mo of age, preparation of Pasteur Institute) were housed under similar living conditions in cages (in groups of four) at room temperature under a controlled light/dark (12-h) cycle with ad libitum access to food and water. A number of sixteen rats were randomly divided to two groups (resistance exercise (T) and control (C); n=8 for each group). The resistance training protocol consisted of climbing a 1-meter–long ladder, with a weight attached to a tail sleeve. Twenty-four hours following the main training session, rats of T and C groups were anaesthetized and the right soleus and flexor hallucis longus (FHL) muscles were removed under sterile conditions via an incision on the dorsolateral aspect of the hind limb. For NT-4/5 and TrkB expression, quantitative real time RT-PCR was used. SPSS software and independent-samples t-test were used for data analysis. The level of significance was set at P < 0.05. Data indicate that resistance training significantly (P<0.05) decreased mRNA expression of NT4/5 in soleus muscle. However, no significant alteration was detected in FHL muscle (P>0.05). Our results also indicate that no significant alterations were detected for TrkB mRNA expression in soleus and FHL muscles (P>0.05). Decrease in mRNA expression of NT4/5 in soleus muscle may be as result of post-translation regulation following resistance training. Also, non-alteration in TrkB mRNA expression was indicated in probable roll of P75 receptor.

Keywords: neurotrophin-4/5 (NT-4/5), TrkB receptor, resistance training, slow and fast muscles

Procedia PDF Downloads 444
397 A Study of the Implications for the Health and Wellbeing of Energy-Efficient House Occupants: A UK-Based Investigation of Indoor Climate and Indoor Air Quality

Authors: Patricia Kermeci

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Policies related to the reduction of both carbon dioxide and energy consumption within the residential sector have contributed towards a growing number of energy-efficient houses being built in several countries. Many of these energy-efficient houses rely on the construction of very well insulated and highly airtight structures, ventilated mechanically. Although energy-efficient houses are indeed more energy efficient than conventional houses, concerns have been raised over the quality of their indoor air and, consequently, the possible adverse health and wellbeing effects for their occupants. Using a longitudinal study design over three different weather seasons (winter, spring and summer), this study has investigated the indoor climate and indoor air quality of different rooms (bedroom, living room and kitchen) in five energy-efficient houses and four conventional houses in the UK. Occupants have kept diaries of their activities during the studied periods and interviews have been conducted to investigate possible behavioural explanations for the findings. Data has been compared with reviews of epidemiological, toxicological and other health related published literature to reveals three main findings. First, it shows that the indoor environment quality of energy-efficient houses cannot be treated as a holistic entity as different rooms presented dissimilar indoor climate and indoor air quality. Thus, such differences might contribute to the health and wellbeing of occupants in different ways. Second, the results show that the indoor environment quality of energy-efficient houses can vary following changes in weather season, leaving occupants at a lower or higher risk of adverse health and wellbeing effects during different weather seasons. Third, one cannot assume that even identical energy-efficient houses provide a similar indoor environment quality. Fourth, the findings reveal that the practices and behaviours of the occupants of energy-efficient houses likely determine whether they enjoy a healthier indoor environment when compared with their control houses. In conclusion, it has been considered vital to understand occupants’ practices and behaviours in order to explain the ways they might contribute to the indoor climate and indoor air quality in energy-efficient houses.

Keywords: energy-efficient house, health and wellbeing, indoor environment, indoor air quality

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396 Generous Edge – Inviting the Spontaneous

Authors: Ofri Earon

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This article is about a growing focus in the city of Copenhagen – the edge zone between the private space inside the residential building and the public space out at the residential street. A slow transition between the private living room and the public urban space creates a mutual benefit. The urban space benefits from an insertion of a homey atmosphere by the extended performance of living rooms to the exterior. The dwelling benefits from belonging to a liveable neighborliness, which means an extension of the private home to a collective home (= the neighborhood). Grounded by this reciprocal value of the edge zone, through the article, it is argued that a wide generosity of the edge zones is of interest among both planners and residents. The article introduces the idea of the edge zone and its possible implications in the development of the liveable residential city. Three examples of ongoing projects at Arkitema Architects are bought to illustrate the challenges and potentials of a generous edge zone. Every example represents a specific dwelling typology in a particular urban context: (1) multi-family residential building in a previous industrial area in the city (2) new courtyard building in the city’s outskirt (3) low and dense residential area out in the suburbia. Throughout these examples, the article seeks to discuss the significance of the edge zone in forthcoming residential areas in Denmark. The analysis of the Danish examples raises the question of why a social behavior that happens spontaneously in the south of Europe has to be carefully implemented in the architecture of north of Europe. In this light, the article ends with a discussion on how to create edge zones that are not designed for a particular usage, but rather as an architectural invitation for varied social behaviors that spontaneously occur in different moments of time by different people. Finally, the article ends with a list of recommendations for the development of the generous edge zone as an open invitation for diverse usage over time.

Keywords: dwelling, edge zone, generosity, livability, urban space

Procedia PDF Downloads 355
395 Multiscale Process Modeling Analysis for the Prediction of Composite Strength Allowables

Authors: Marianna Maiaru, Gregory M. Odegard

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During the processing of high-performance thermoset polymer matrix composites, chemical reactions occur during elevated pressure and temperature cycles, causing the constituent monomers to crosslink and form a molecular network that gradually can sustain stress. As the crosslinking process progresses, the material naturally experiences a gradual shrinkage due to the increase in covalent bonds in the network. Once the cured composite completes the cure cycle and is brought to room temperature, the thermal expansion mismatch of the fibers and matrix cause additional residual stresses to form. These compounded residual stresses can compromise the reliability of the composite material and affect the composite strength. Composite process modeling is greatly complicated by the multiscale nature of the composite architecture. At the molecular level, the degree of cure controls the local shrinkage and thermal-mechanical properties of the thermoset. At the microscopic level, the local fiber architecture and packing affect the magnitudes and locations of residual stress concentrations. At the macroscopic level, the layup sequence controls the nature of crack initiation and propagation due to residual stresses. The goal of this research is use molecular dynamics (MD) and finite element analysis (FEA) to predict the residual stresses in composite laminates and the corresponding effect on composite failure. MD is used to predict the polymer shrinkage and thermomechanical properties as a function of degree of cure. This information is used as input into FEA to predict the residual stresses on the microscopic level resulting from the complete cure process. Virtual testing is subsequently conducted to predict strength allowables. Experimental characterization is used to validate the modeling.

Keywords: molecular dynamics, finite element analysis, processing modeling, multiscale modeling

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394 Outcome at the Extreme of Viability: A Single-Centre Experience

Authors: Antonia Harold-Barry, Eugene Dempsey

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Background: The objective is to examine the survival and outcome of infants born under 26 weeks gestation in an Irish tertiary maternity hospital from 2007-2016 and to describe the survival and neurodevelopmental outcomes of these extremely preterm infants. Method: The population is 132 infants born at 23, 24, and 25 weeks in Cork University Maternity Hospital from 2007 to 2016. Ethical approval was granted by the Cork Clinical Research Ethics Committee. Patient details were obtained from the Vermont Oxford and Badger Networks. Survival rates and Bayley scores were calculated to assess neurodevelopmental outcomes. Statistical analysis with SPSS included frequencies, distributions, and comparisons between data from 2007-2011 and 2012-2016. Results: Overall survival rate was 63%. Of the surviving babies, 61% had Bayley scores calculated. Survival stood at 39% for delivery at 23 weeks, 50% at 24 weeks, and 83% at 25 weeks. The 2012 to 2016 cohort has shown further increases in survival, with 50% of babies at 23 weeks, 58% at 24 weeks, and 89% at 25 weeks. Corresponding figures for 2007-2011 are 20%, 39%, and 75%. Gestational age and incidence of periventricular leukomalacia were statistically significant, with a p-value of 0.022. Gestational age and delivery room deaths had a p-value of 0.025, as did gestational age and birth weight. A comparison of the two cohorts (2007-2011 and 2012-2016) with the administration of antenatal steroids showed a statistically significant p-value of 0.044. Conclusion: There is less morbidity and mortality in infants born at 25 than at 23 or 24 weeks. Survival of extremely premature infants has increased significantly over the past ten years. Survival rates with normal neurodevelopmental outcomes are comparable with international standards and reflect positive changes in attitude and practices in neonatal intensive care. This study will inform parents about the potential outcomes of extreme prematurity and policy regarding the management of extreme prematurity.

Keywords: extreme of viability, neurodevelopmental outcome, periventricular leukomalacia, prematurity

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393 Magnetic Chloromethylated Polymer Nanocomposite for Selective Pollutant Removal

Authors: Fabio T. Costa, Sergio E. Moya, Marcelo H. Sousa

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Nanocomposites designed by embedding magnetic nanoparticles into a polymeric matrix stand out as ideal magnetic-hybrid and magneto-responsive materials as sorbents for removal of pollutants in environmental applications. Covalent coupling is often desired for the immobilization of species on these nanocomposites, in order to keep them permanently bounded, not desorbing or leaching over time. Moreover, unwanted adsorbates can be separated by successive washes/magnetic separations, and it is also possible to recover the adsorbate covalently bound to the nanocomposite surface through detaching/cleavage protocols. Thus, in this work, we describe the preparation and characterization of highly-magnetizable chloromethylated polystyrene-based nanocomposite beads for selective covalent coupling in environmental applications. For synthesis optimization, acid resistant core-shelled maghemite (γ-Fe₂O₃) nanoparticles were coated with oleate molecules and directly incorporated into the organic medium during a suspension polymerization process. Moreover, the cross-linking agent ethylene glycol dimethacrylate (EGDMA) was utilized for co-polymerization with the 4-vinyl benzyl chloride (VBC) to increase the resistance of microbeads against leaching. After characterizing samples with XRD, ICP-OES, TGA, optical, SEM and TEM microscopes, a magnetic composite consisting of ~500 nm-sized cross-linked polymeric microspheres embedding ~8 nm γ-Fe₂O₃ nanoparticles was verified. This nanocomposite showed large room temperature magnetization (~24 emu/g) due to the high content in maghemite (~45 wt%) and resistance against leaching even in acidic media. Moreover, the presence of superficial chloromethyl groups, probed by FTIR and XPS spectroscopies and confirmed by an amination test can selectively adsorb molecules through the covalent coupling and be used in molecular separations as shown for the selective removal of 4-aminobenzoic acid from a mixture with benzoic acid.

Keywords: nanocomposite, magnetic nanoparticle, covalent separation, pollutant removal

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392 Mechanical Properties of Waste Clay Brick Based Geopolymer Cured at Various Temperature

Authors: Shihab Ibrahim

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Geopolymer binders as an alternative binder system to ordinary Portland cement are the focus of the past 2 decades of researches. In order to eliminate CO2 emission by cement manufacturing and utilizing construction waste as a source material, clean waste clay bricks which are the waste from Levent Brick factory was activated with a mixture of sodium hydroxide and sodium silicate solution. 12 molarity of sodium hydroxide solution was used and the ratio of sodium silicate to sodium hydroxide was 2.5. Alkaline solution to clay brick powder ratio of 0.35, 0.4, 0.45, and 0.5 was studied. Alkaline solution to powder ratio of 0.4 was found to be optimum ratio to have the same workability as ordinary Portland cement paste. Compressive strength of the clay brick based geopolymer paste samples was evaluated under different curing temperatures and curing durations. One day compressive strength of 57.3 MPa after curing at 85C for 24 hours was obtained which was higher than 7 days compressive strength of ordinary Portland cement paste. The highest compressive strength 71.4 MPa was achieved at seventh day age for the geopolymer paste samples cured at 85C for 24 hours. It was found that 8 hour curing at elevated temperature 85C, is sufficient to get 96% of total strength. 37.4 MPa strength at seventh day of clay brick based geopolymer sample cured at room temperature was achieved. Water absorption around 10% was found for clay brick based geopolymer samples cured at different temperatures with compare to 9.14% water absorption of ordinary Portland cement paste. The clay brick based geopolymer binder can have the potentiality to be used as an alternative binder to Portland cement in a case that the heat treatment provided. Further studies are needed in order to produce the binder in a way that can harden and gain strength without any elevated curing.

Keywords: construction and demolition waste, geopolymer, clay brick, compressive strength.

Procedia PDF Downloads 259
391 Eco-Fashion Dyeing of Denim and Knitwear with Particle-Dyes

Authors: Adriana Duarte, Sandra Sampaio, Catia Ferreira, Jaime I. N. R. Gomes

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With the fashion of faded worn garments the textile industry has moved from indigo and pigments to dyes that are fixed by cationization, with products that can be toxic, and that can show this effect after washing down the dye with friction and/or treating with enzymes in a subsequent operation. Increasingly they are treated with bleaches, such as hypochlorite and permanganate, both toxic substances. An alternative process is presented in this work for both garment and jet dyeing processes, without the use of pre-cationization and the alternative use of “particle-dyes”. These are hybrid products, made up by an inorganic particle and an organic dye. With standard soluble dyes, it is not possible to avoid diffusion into the inside of the fiber unless using previous cationization. Only in this way can diffusion be avoided keeping the centre of the fibres undyed so as to produce the faded effect by removing the surface dye and showing the white fiber beneath. With “particle-dyes”, previous cationization is avoided. By applying low temperatures, the dye does not diffuse completely into the inside of the fiber, since it is a particle and not a soluble dye, being then able to give the faded effect. Even though bleaching can be used it can also be avoided, by the use of friction and enzymes they can be used just as for other dyes. This fashion brought about new ways of applying reactive dyes by the use of previous cationization of cotton, lowering the salt, and temperatures that reactive dyes usually need for reacting and as a side effect the application of a more environmental process. However, cationization is a process that can be problematic in applying it outside garment dyeing, such as jet dyeing, being difficult to obtain level dyeings. It also should be applied by a pad-fix or Pad-batch process due to the low affinity of the pre-cationization products making it a more expensive process, and the risk of unlevelness in processes such as jet dyeing. Wit particle-dyes, since no pre-cationizartion is necessary, they can be applied in jet dyeing. The excess dye is fixed by a fixing agent, fixing the insoluble dye onto the surface of the fibers. By applying the fixing agent only one to 1-3 rinses in water at room temperature are necessary, saving water and improving the washfastness.

Keywords: denim, garment dyeing, worn look, eco-fashion

Procedia PDF Downloads 537
390 Corruption, Institutional Quality and Economic Growth in Nigeria

Authors: Ogunlana Olarewaju Fatai, Kelani Fatai Adeshina

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The interplay of corruption and institutional quality determines how effective and efficient an economy progresses. An efficient institutional quality is a key requirement for economic stability. Institutional quality in most cases has been used interchangeably with Governance and these have given room for proxies that legitimized Governance as measures for institutional quality. A poorly-tailored institutional quality has a penalizing effect on corruption and economic growth, while defective institutional quality breeds corruption. Corruption is a hydra-headed phenomenon as it manifests in different forms. The most celebrated definition of corruption is given as “the use or abuse of public office for private benefits or gains”. It also denotes an arrangement between two mutual parties in the determination and allocation of state resources for pecuniary benefits to circumvent state efficiency. This study employed Barro (1990) type augmented model to analyze the nexus among corruption, institutional quality and economic growth in Nigeria using annual time series data, which spanned the period 1996-2019. Within the analytical framework of Johansen Cointegration technique, Error Correction Mechanism (ECM) and Granger Causality tests, findings revealed a long-run relationship between economic growth, corruption and selected measures of institutional quality. The long run results suggested that all the measures of institutional quality except voice & accountability and regulatory quality are positively disposed to economic growth. Moreover, the short-run estimation indicated a reconciliation of the divergent views on corruption which pointed at “sand the wheel” and “grease the wheel” of growth. In addition, regulatory quality and the rule of law indicated a negative influence on economic growth in Nigeria. Government effectiveness and voice & accountability, however, indicated a positive influence on economic growth. The Granger causality test results suggested a one-way causality between GDP and Corruption and also between corruption and institutional quality. Policy implications from this study pointed at checking corruption and streamlining institutional quality framework for better and sustained economic development.

Keywords: institutional quality, corruption, economic growth, public policy

Procedia PDF Downloads 170
389 Stability of Pump Station Cavern in Chagrin Shale with Time

Authors: Mohammad Moridzadeh, Mohammad Djavid, Barry Doyle

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An assessment of the long-term stability of a cavern in Chagrin shale excavated by the sequential excavation method was performed during and after construction. During the excavation of the cavern, deformations of rock mass were measured at the surface of excavation and within the rock mass by surface and deep measurement instruments. Rock deformations were measured during construction which appeared to result from the as-built excavation sequence that had potentially disturbed the rock and its behavior. Also some additional time dependent rock deformations were observed during and post excavation. Several opinions have been expressed to explain this time dependent deformation including stress changes induced by excavation, strain softening (or creep) in the beddings with and without clay and creep of the shaley rock under compressive stresses. In order to analyze and replicate rock behavior observed during excavation, including current and post excavation elastic, plastic, and time dependent deformation, Finite Element Analysis (FEA) was performed. The analysis was also intended to estimate long term deformation of the rock mass around the excavation. Rock mass behavior including time dependent deformation was measured by means of rock surface convergence points, MPBXs, extended creep testing on the long anchors, and load history data from load cells attached to several long anchors. Direct creep testing of Chagrin Shale was performed on core samples from the wall of the Pump Room. Results of these measurements were used to calibrate the FEA of the excavation. These analyses incorporate time dependent constitutive modeling for the rock to evaluate the potential long term movement in the roof, walls, and invert of the cavern. The modeling was performed due to the concerns regarding the unanticipated behavior of the rock mass as well as the forecast of long term deformation and stability of rock around the excavation.

Keywords: Cavern, Chagrin shale, creep, finite element.

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388 Evaluation of Outpatient Management of Proctological Surgery under Saddle Block

Authors: Bouhouf Atef, Beloulou Mohamed Lamine

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Introduction: Outpatient surgery is continually developing compared to conventional inpatient surgery; its rate is constantly increasing every year due to global socio-economic pressure. Most hospitals continue to perform proctologic surgery in conventional hospitalization. Purpose: As part of a monocentric prospective descriptive study, we examined the feasibility of proctologic surgery under saddle block on an outpatient basis with the same safety conditions as in traditional hospitalization. Material and methods: This is a monocentric prospective descriptive study spread over a period of 24 months, from December 2018 to December 2020 including 150 patients meeting the medico-surgical and socio-environmental criteria of eligibility for outpatient surgery, operated for proctological pathologies under saddle block in outpatient mode, in the surgery department of the regional military hospital of Constantine Algeria. The data were collected and analyzed by the biomedical statistics software Epi-info and Microsoft Excel, then compared with other related studies. Results: This study involved over a period of two years, 150 male patients with an average age of 32 years (20-64). Most patients (95,33%) were ASA I class, and 4,67% ASA II class. All patients received saddle blocks. The average length of stay of patients was six hours. The quality indicators in outpatient surgery in our study were: zero (0)% of deprogrammings, three (3)% of conversions to full hospitalization, 0,7% of readmissions, an average waiting time before access to the operating room of 83 minutes without delay of discharge, a satisfaction rate of 90,8% and a reduction in the cost compared to conventional inpatient surgery in proportions ranging from – 32,6% and – 48,75%. Conclusions: The outpatient management of proctological surgery under saddle block is very beneficial in terms of safety, efficiency, simplicity, and economy. Our results are in line with those of the literature and our work deserves to be continued to include many patients.

Keywords: outpatient surgery, proctological surgery, saddle block, satisfaction, cost

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387 Analyzing the Sociolinguistic Profile of the Algerian Community in the UK in terms of French Language Use: The Case of Émigré Ph.D. Students

Authors: Hadjer Chellia

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the present study reports on second language use among Algerian international students in the UK. In Algeria, French has an important status among the Algerian verbal repertoires due to colonial reasons. This has triggered many language conflicts and many debates among policy makers in Algeria. In higher education, Algerian English students’ sociolinguistic profile is characterised by the use of French as a sign of prestige. What may leave room for debate is the effect of crossing borders towards the UK as a result of international mobility programmes, a transition which could add more complexity since French, is not so significant as a language in the UK context. In this respect, the micro-objective is to explore the fate of French use among Ph.D. students in the UK as a newly established group vis-à-vis English. To fulfill the purpose of the present inquiry, the research employs multiple approaches in which semi-structured interview is a primary source of data to know participants’ attitudes about French use, targeting both their pre-migratory experience and current one. Web-based questionnaires are set up to access larger population. Focus group sessions are further procedures of scrutiny in this piece of work to explore the actual linguistic behaviours. Preliminary findings from both interviews and questionnaires reveal that students’ current experience, particularly living in the UK, affects their pre-migratory attitudes towards French language and its use. The overall findings are expected to bring manifold contributions to the field of research among which is setting factors that influence language use among newly established émigrés communities. The research is also relevant to international students’ experience of study abroad in terms of language use in the guise of internationalization of higher education, mobility and exchange programmes. It could contribute to the sociolinguistics of the Algerian diaspora: the dispersed residence of non-native communities - not to mention its significance on the Algerian research field abroad.

Keywords: Algerian diaspora, French language, language maintenance, language shift, mobility

Procedia PDF Downloads 343