Search results for: long-term bridge repair schedule
670 The Effect of Simultaneous Doping of Silicate Bioglass with Alkaline and Alkaline-Earth Elements on Biological Behavior
Authors: Tannaz Alimardani, Amirhossein Moghanian, Morteza Elsa
Abstract:
Bioactive glasses (BGs) are a group of surface-reactive biomaterials used in clinical applications as implants or filler materials in the human body to repair and replace diseased or damaged bone. Sol-gel technique was employed to prepare a SiO₂-CaO-P₂O₅ glass with a nominal composition of 58S BG with the addition of Sr and Li modifiers which imparts special properties to the BG. The effect of simultaneous addition of Sr and Li on bioactivity and biocompatibility, proliferation, alkaline phosphatase (ALP) activity of osteoblast cell line MC3T3-E1 and antibacterial property against methicillin-resistant Staphylococcus aureus (MRSA) bacteria were examined. BGs were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy before and after soaking the samples in the simulated body fluid (SBF) for different time intervals to characterize the formation of hydroxyapatite (HA) formed on the surface of BGs. Structural characterization indicated that the simultaneous presence of 5% Sr and 5% Li in 58S-BG composition not only did not retard HA formation because of the opposite effect of Sr and Li of the dissolution of BG in the SBF, but also stimulated the differentiation and proliferation of MC3T3-E1s. Moreover, the presence of Sr and Li on the dissolution of the ions resulted in an increase in the mean number of DAPI-labeled nuclei which was in good agreement with the live/dead assay. The result of antibacterial tests revealed that Sr and Li-substituted 58S bioactive glass exhibited a potential antibacterial effect against MRSA bacteria. Because of optimal proliferation and ALP activity of MC3T3-E1cells, proper bioactivity and high antibacterial potential against MRSA, BG-5/5 is suggested as a multifunctional candidate for bone tissue engineering.Keywords: alkaline, alkaline earth, bioglass, co-doping, ion release
Procedia PDF Downloads 224669 Unbranched, Saturated, Carboxylic Esters as Phase-Change Materials
Authors: Anastasia Stamatiou, Melissa Obermeyer, Ludger J. Fischer, Philipp Schuetz, Jörg Worlitschek
Abstract:
This study evaluates unbranched, saturated carboxylic esters with respect to their suitability to be used as storage media for latent heat storage applications. Important thermophysical properties are gathered both by means of literature research as well as by experimental measurements. Additionally, esters are critically evaluated against other common phase-change materials in terms of their environmental impact and their economic potential. The experimental investigations are performed for eleven selected ester samples with a focus on the determination of their melting temperature and their enthalpy of fusion using differential scanning calorimetry. Transient Hot Bridge was used to determine the thermal conductivity of the liquid samples while thermogravimetric analysis was employed for the evaluation of the 5% weight loss temperature as well as of the decomposition temperature of the non-volatile samples. Both experimental results and literature data reveal the high potential of esters as phase-change materials. Their good thermal and environmental properties as well as the possibility for production from natural sources (e.g. vegetable oils) render esters as very promising for future storage applications. A particularly high short term application potential of esters could lie in low temperature storage applications where the main alternative is using salt hydrates as phase-change material.Keywords: esters, phase-change materials, thermal properties, latent heat storage
Procedia PDF Downloads 415668 Response Delay Model: Bridging the Gap in Urban Fire Disaster Response System
Authors: Sulaiman Yunus
Abstract:
The need for modeling response to urban fire disaster cannot be over emphasized, as recurrent fire outbreaks have gutted most cities of the world. This necessitated the need for a prompt and efficient response system in order to mitigate the impact of the disaster. Promptness, as a function of time, is seen to be the fundamental determinant for efficiency of a response system and magnitude of a fire disaster. Delay, as a result of several factors, is one of the major determinants of promptgness of a response system and also the magnitude of a fire disaster. Response Delay Model (RDM) intends to bridge the gap in urban fire disaster response system through incorporating and synchronizing the delay moments in measuring the overall efficiency of a response system and determining the magnitude of a fire disaster. The model identified two delay moments (pre-notification and Intra-reflex sequence delay) that can be elastic and collectively plays a significant role in influencing the efficiency of a response system. Due to variation in the elasticity of the delay moments, the model provides for measuring the length of delays in order to arrive at a standard average delay moment for different parts of the world, putting into consideration geographic location, level of preparedness and awareness, technological advancement, socio-economic and environmental factors. It is recommended that participatory researches should be embarked on locally and globally to determine standard average delay moments within each phase of the system so as to enable determining the efficiency of response systems and predicting fire disaster magnitudes.Keywords: delay moment, fire disaster, reflex sequence, response, response delay moment
Procedia PDF Downloads 207667 Keying Effect During Fracture of Stainless Steel
Authors: Farej Ahmed Emhmmed
Abstract:
Fracture of duplex stainless steels (DSS) was investigated in air and in 3.5 wt % NaCl solution. Tow sets of fatigued specimens were heat treated at 475ºC for different times and pulled to failure either in air or after kept in 3.5% NaCl with polarization of -900 mV/ SCE. Fracture took place in general by ferrite cleavage and austenite ductile fracture in transgranular mode. Specimens measured stiffness (Ms) was affected by the aging time, with higher values measured for specimens aged for longer times. Microstructural features played a role in "blocking" the crack propagation process leading to lower the CTOD values specially for specimens aged for short times. Unbroken ligaments/ austenite were observed at the crack wake. These features may exerted a bridging stress, blocking effect, at the crack tip giving resistance to the crack propagation process i.e the crack mouth opening was reduced. Higher stress intensity factor Kıc values were observed with increased amounts of crack growth suggesting longer zone of unbroken ligaments in the crack wake. The bridging zone was typically several mm in length. Attempt to model the bridge stress was suggested to understand the role of ligaments/unbroken austenite in increasing the fracture toughness factor.Keywords: stainless steels, fracture toughness, crack keying effect, ligaments
Procedia PDF Downloads 359666 Numerical Homogenization of Nacre
Authors: M. Arunachalam, M. Pandey
Abstract:
Nacre, a biological material that forms the inner-layer of sea shells can achieve high toughness and strength by way of staggered arrangement of strong tablets with soft and weak organic interface. Under applied loads the tablets slide over the adjacent tablets, thus generating inelastic deformation and toughness on macroscopic scale. A two dimensional finite element based homogenization methodology is adopted for obtaining the effective material properties of Nacre using a representative volume element (RVE) at finite deformations. In this work, the material behaviour for tablet and interface are assumed to be Isotropic elastic and Isotropic elastic-perfectly plastic with strain softening respectively. Numerical experiments such as uniaxial tension test along X, Y directions and simple shear test are performed on the RVE with uniform displacement and periodic constraints applied at the RVE boundaries to obtain the anisotropic homogenized response and maximum local stresses within each constituents of Nacre. Homogenized material model is then tested for macroscopic structure under three point bending condition and the results obtained are comparable with the results obtained for detailed microstructure based structure, thus homogenization provides a bridge between macroscopic scale and microscopic scale and homogenized material properties obtained from microstructural (RVE) analysis could be used in large scale structural analysis.Keywords: finite element, homogenization, inelastic deformation, staggered arrangement
Procedia PDF Downloads 318665 Fuzzy Set Qualitative Comparative Analysis in Business Models' Study
Authors: K. Debkowska
Abstract:
The aim of this article is presenting the possibilities of using Fuzzy Set Qualitative Comparative Analysis (fsQCA) in researches concerning business models of enterprises. FsQCA is a bridge between quantitative and qualitative researches. It's potential can be used in analysis and evaluation of business models. The article presents the results of a study conducted on the basis of enterprises belonging to different sectors: transport and logistics, industry, building construction, and trade. The enterprises have been researched taking into account the components of business models and the financial condition of companies. Business models are areas of complex and heterogeneous nature. The use of fsQCA has enabled to answer the following question: which components of a business model and in which configuration influence better financial condition of enterprises. The analysis has been performed separately for particular sectors. This enabled to compare the combinations of business models' components which actively influence the financial condition of enterprises in analyzed sectors. The following components of business models were analyzed for the purposes of the study: Key Partners, Key Activities, Key Resources, Value Proposition, Channels, Cost Structure, Revenue Streams, Customer Segment and Customer Relationships. These components of the study constituted the variables shaping the financial results of enterprises. The results of the study lead us to believe that fsQCA can help in analyzing and evaluating a business model, which is important in terms of making a business decision about the business model used or its change. In addition, results obtained by fsQCA can be applied by all stakeholders connected with the company.Keywords: business models, components of business models, data analysis, fsQCA
Procedia PDF Downloads 170664 The Effect of Withania Somnifera in Alloxan Induced Diabetic Rabbits
Authors: Farah Ali, Tehreem Fayyaz, Musadiq Idris
Abstract:
The present work was undertaken to investigate effects of various extracts of withania somnifera for anti-diabetic activity in alloxan induced diabetic rabbits. Rabbits were acclimatized for a week to standard laboratory temperature. Animals were fed according to a strict schedule (8 am, 3 pm and 10 pm) with green fodder (Medicago sativa) and tap water ad libitum. Animals were divided into nine groups of six rabbits each in a random manner. Body weights and physical activities of all rabbits were recorded before start of experiments. The animals of group 1 and 2 were given lactose (250 mg/kg, p.o) and Withania somniferaroot powder (100 mg/kg, p.o) respectively daily from day 1-20. Animals of group 3 were given alloxan (100 mg/kg, i.v) as a single dose on day 1. Powdered root of Withania somnifera in the doses of 100, 150, 200 mg/kg and its aqueous and ethanol extracts (equivalent to 200 mg/kg of crude drug) were given to the treated animals (groups 4-8), respectively by oral route for three weeks (day 1-20o.d), along with alloxan (100 mg/kg, i.v) as a single dose on day 1. Group 9 was treated with metformin (200 mg/kg, p.o) daily from day 1-20, along with a single dose of alloxan (100 mg/ kg, i.v) on day 1. Fasting serum glucose concentration in groups 3-9 was increased significantly (p<0.05) on day 3, with a maximum increase (215.3 mg/dl) in animals of toxic control (TC) group (3) on day 21 of the experiment as compared to normal control (NC) group (1). Effects of different doses (100, 150, 200 mg/kg, p.o) of W. somnifera root powder (WS) decreased the fasting serum glucose concentration as compared to toxic control group, with a maximum decrease (88.3 mg/dl) in group 2 (treated control) on day 21 of the experiment. Metformin (200 mg/kg, p.o) (reference control), aqueous extract (AWS) and ethanol extract (EWS) of W. somnifera (equivalent to 100 mg/kg W.somnifera root, p.o) antagonized the effects of alloxan as compared to toxic control group. These results indicate that the W. somnifera possess significant anti–diabetic activity.Keywords: diabetes, serum, glucose, blood, sugar, rabbits
Procedia PDF Downloads 522663 Empirical Study of Correlation between the Cost Performance Index Stability and the Project Cost Forecast Accuracy in Construction Projects
Authors: Amin AminiKhafri, James M. Dawson-Edwards, Ryan M. Simpson, Simaan M. AbouRizk
Abstract:
Earned value management (EVM) has been introduced as an integrated method to combine schedule, budget, and work breakdown structure (WBS). EVM provides various indices to demonstrate project performance including the cost performance index (CPI). CPI is also used to forecast final project cost at completion based on the cost performance during the project execution. Knowing the final project cost during execution can initiate corrective actions, which can enhance project outputs. CPI, however, is not constant during the project, and calculating the final project cost using a variable index is an inaccurate and challenging task for practitioners. Since CPI is based on the cumulative progress values and because of the learning curve effect, CPI variation dampens and stabilizes as project progress. Although various definitions for the CPI stability have been proposed in literature, many scholars have agreed upon the definition that considers a project as stable if the CPI at 20% completion varies less than 0.1 from the final CPI. While 20% completion point is recognized as the stability point for military development projects, construction projects stability have not been studied. In the current study, an empirical study was first conducted using construction project data to determine the stability point for construction projects. Early findings have demonstrated that a majority of construction projects stabilize towards completion (i.e., after 70% completion point). To investigate the effect of CPI stability on cost forecast accuracy, the correlation between CPI stability and project cost at completion forecast accuracy was also investigated. It was determined that as projects progress closer towards completion, variation of the CPI decreases and final project cost forecast accuracy increases. Most projects were found to have 90% accuracy in the final cost forecast at 70% completion point, which is inlined with findings from the CPI stability findings. It can be concluded that early stabilization of the project CPI results in more accurate cost at completion forecasts.Keywords: cost performance index, earned value management, empirical study, final project cost
Procedia PDF Downloads 156662 Stressful Life Events and Their Influence on Childhood Obesity and Emotional Well-Being: Cross-Sectional Study
Authors: M. Rojo, M. Blanco, T. Lacruz, S. Solano, L. Beltran, M. Graell, A. R. Sepulveda.
Abstract:
There is an association between an early accumulation of Stressful Life Events (SLE) during childhood and various physical and psychological health complications. However, there are only a few studies on this topic in children and adolescents with overweight or obesity. The general aim of the study was to evaluate the accumulation and type of SLE in 200 children from 8 to 12 years old and analyze the relationship with their emotional well-being and weight status (obesity, overweight and normal weight). The children and their families completed an interview. The evaluated variables that are included in this study are sociodemographic measures, medical/psychological history, anthropometric measures (BMI, z-BMI), and psychological variables (children's clinical interview K-SADS-PL(Schedule for Affective Disorders and Schizophrenia for School-Age Children Present and Lifetime Version) and battery of questionnaires). Results: Children with overweight and obesity accumulate more stressful events from an early age and have a significantly higher percentage of psychiatric diagnoses, compared to their peers with normal weight. Presenting a child psychiatric disorder is related to greater z-BMI and the total number of SLE (p < 0.001). A higher z-BMI is also related to a greater number of stressful events during childhood. There is also a positive and significant relationship between the total number of SLE and worse emotional well-being (higher levels of anxious and depressive symptoms and low self-esteem of children) (p < 0.01). Conclusion: Children with overweight and obesity grow up in a family, school, and social context where more stressors are accumulated. This is also directly associated with worse emotional well-being. It is necessary to implement multidisciplinary prevention and intervention strategies in different changes (school, family, and health). This study is included in a project funded by the Ministry of Innovation and Science (PSI2011-23127).Keywords: childhood obesity, emotional well-being, psychopathology, stressful life events
Procedia PDF Downloads 127661 Smart Coating for Enhanced Corneal Healing via Delivering Progranulin
Authors: Dan Yan, Yunuo Zhang, Yuhan Huang, Weijie Ouyang
Abstract:
The cornea serves as a vital protective barrier for the eye; however, it is prone to injury and damage that can disrupt corneal epithelium and nerves, triggering inflammation. Therefore, understanding the biological effects and molecular mechanisms involved in corneal wound healing and identifying drugs targeting these pathways is crucial for researchers in this field. This study aimed to investigate the therapeutic potential of progranulin (PGRN) in treating corneal injuries. Our findings demonstrated that PGRN significantly enhanced corneal wound repair by accelerating corneal re-epithelialization and re-innervation. In vitro experiments with cultured epithelial cells and trigeminal ganglion cells further revealed that PGRN stimulated corneal epithelial cell proliferation and promoted axon growth in trigeminal ganglion cells. Through RNA-sequencing (RNA-seq) analysis and other experimental techniques, we discovered that PGRN exerted its healing effects by modulating the Wnt signaling pathway, which played a critical role in repairing epithelial cells and promoting axon regeneration in trigeminal neurons. Importantly, our study highlighted the anti-inflammatory properties of PGRN by inhibiting the NF-κB signaling pathway, leading to decreased infiltration of macrophages. In conclusion, our findings underscored the potential of PGRN in facilitating corneal wound healing by promoting corneal epithelial cell proliferation, trigeminal ganglion cell axon regeneration, and suppressing ocular inflammation. These results suggest that PGRN could potentially expedite the healing process and improve visual outcomes in patients with corneal injuries.Keywords: cornea, wound healing, progranulin, corneal epithelial cells, trigeminal ganglion cells
Procedia PDF Downloads 57660 Design of 3D Bioprinted Scaffolds for Cartilage Regeneration
Authors: Gloria Pinilla, Jose Manuel Baena, Patricia Gálvez-Martín, Juan Antonio Marchad
Abstract:
Cartilage is a dense connective tissue with limited self-repair properties. Currently, the therapeutic use of autologous or allogenic chondrocytes makes up an alternative therapy to the pharmacological treatment. The design of a bioprinted 3D cartilage with chondrocytes and biodegradable biomaterials offers a new therapeutic alternative able of bridging the limitations of current therapies in the field. We have developed an enhanced printing processes-Injection Volume Filling (IVF) to increase the viability and survival of the cells when working with high-temperature thermoplastics without the limitation of the scaffold geometry in contact with cells. We have demonstrated the viability of the printing process using chondrocytes for cartilage regeneration. This development will accelerate the clinical uptake of the technology and overcomes the current limitation when using thermoplastics as scaffolds. An alginate-based hydrogel combined with human chondrocytes (isolated from osteoarthritis patients) was formulated as bioink-A and the polylactic acid as bioink-B. The bioprinting process was carried out with the REGEMAT V1 bioprinter (Regemat 3D, Granada-Spain) through a IVF. The printing capacity of the bioprinting plus the viability and cell proliferation of bioprinted chondrociytes was evaluated after five weeks by confocal microscopy and Alamar Blue Assay (Biorad). Results showed that the IVF process does not decrease the cell viability of the chondrocytes during the printing process as the cells do not have contact with the thermoplastic at elevated temperatures. The viability and cellular proliferation of the bioprinted artificial 3D cartilage increased after 5 weeks. In conclusion, this study demonstrates the potential use of Regemat V1 for 3D bioprinting of cartilage and the viability of bioprinted chondrocytes in the scaffolds for application in regenerative medicine.Keywords: cartilage regeneration, bioprinting, bioink, scaffold, chondrocyte
Procedia PDF Downloads 313659 The Effect of Eight Weeks of Aerobic Training on Indices of Cardio-Respiratory and Exercise Tolerance in Overweight Women with Chronic Asthma
Authors: Somayeh Negahdari, Mohsen Ghanbarzadeh, Masoud Nikbakht, Heshmatolah Tavakol
Abstract:
Asthma, obesity and overweight are the main factors causing change within the heart and respiratory airways. Asthma symptoms are normally observed during exercising. Epidemiological studies have indicated asthma symptoms occurring due to certain lifestyle habits; for example, a sedentary lifestyle. In this study, eight weeks of aerobic exercises resulted in a positive effect overall in overweight women experiencing mild chronic asthma. The quasi-experimental applied research has been done based on experimental and control groups. The experimental group (seven patients) and control group (n = 7) were graded before and after the test. According to the Borg dyspnea and fatigue Perception Index, the training intensity has determined. Participants in the study performed a sub-maximal aerobic activity schedule (45% to 80% of maximum heart rate) for two months, while the control group (n = 7) stayed away from aerobic exercise. Data evaluation and analysis of covariance compared both the pre-test and post-test with paired t-test at significance level of P≤ 0.05. After eight weeks of exercise, the results of the experimental group show a significant decrease in resting heart rate, systolic blood pressure, minute ventilation, while a significant increase in maximal oxygen uptake and tolerance activity (P ≤ 0.05). In the control group, there was no significant difference in these parameters ((P ≤ 0.05). The results indicate the aerobic activity can strengthen the respiratory muscles, while other physiological factors could result in breathing and heart recovery. Aerobic activity also resulted in favorable changes in cardiovascular parameters, and exercise tolerance of overweight women with chronic asthma.Keywords: asthma, respiratory cardiac index, exercise tolerance, aerobic, overweight
Procedia PDF Downloads 234658 Development of 3D Printed, Conductive, Biodegradable Nerve Conduits for Neural Regeneration
Authors: Wei-Chia Huang, Jane Wang
Abstract:
Damage to nerves is considered one of the most irreversible injuries. The regeneration of nerves has always been an important topic in regenerative medicine. In general, damage to human tissue will naturally repair overtime. However, when the nerves are damaged, healed flesh wound cannot guarantee full restoration to its original function, as truncated nerves are often irreversible. Therefore, the development of treatment methods to successfully guide and accelerate the regeneration of nerves has been highly sought after. In order to induce nerve tissue growth, nerve conduits are commonly used to help reconnect broken nerve bundles to provide protection to the location of the fracture while guiding the growth of the nerve bundles. To prevent the protected tissue from becoming necrotic and to ensure the growth rate, the conduits used are often modified with microstructures or blended with neuron growth factors that may facilitate nerve regeneration. Electrical stimulation is another attempted treatment for medical rehabilitation. With appropriate range of voltages and stimulation frequencies, it has been demonstrated to promote cell proliferation and migration. Biodegradability are critical for medical devices like nerve conduits, while conductive polymers pose great potential toward the differentiation and growth of nerve cells. In this work, biodegradability and conductivity were combined into a novel biodegradable, photocurable, conductive polymer composite materials by embedding conductive nanoparticles in poly(glycerol sebacate) acrylate (PGSA) and 3D-printed into nerve conduits. Rat pheochromocytoma cells and rat neuronal Schwann cells were chosen for the in vitro tests of the conduits and had demonstrate selective growth upon culture in the conductive conduits with built-in microchannels and electrical stimulation.Keywords: biodegradable polymer, 3d printing, neural regeneration, electrical stimulation
Procedia PDF Downloads 104657 A Case Study on Machine Learning-Based Project Performance Forecasting for an Urban Road Reconstruction Project
Authors: Soheila Sadeghi
Abstract:
In construction projects, predicting project performance metrics accurately is essential for effective management and successful delivery. However, conventional methods often depend on fixed baseline plans, disregarding the evolving nature of project progress and external influences. To address this issue, we introduce a distinct approach based on machine learning to forecast key performance indicators, such as cost variance and earned value, for each Work Breakdown Structure (WBS) category within an urban road reconstruction project. Our proposed model leverages time series forecasting techniques, namely Autoregressive Integrated Moving Average (ARIMA) and Long Short-Term Memory (LSTM) networks, to predict future performance by analyzing historical data and project progress. Additionally, the model incorporates external factors, including weather patterns and resource availability, as features to improve forecast accuracy. By harnessing the predictive capabilities of machine learning, our performance forecasting model enables project managers to proactively identify potential deviations from the baseline plan and take timely corrective measures. To validate the effectiveness of the proposed approach, we conduct a case study on an urban road reconstruction project, comparing the model's predictions with actual project performance data. The outcomes of this research contribute to the advancement of project management practices in the construction industry by providing a data-driven solution for enhancing project performance monitoring and control.Keywords: project performance forecasting, machine learning, time series forecasting, cost variance, schedule variance, earned value management
Procedia PDF Downloads 39656 The Inherent Flaw in the NBA Playoff Structure
Authors: Larry Turkish
Abstract:
Introduction: The NBA is an example of mediocrity and this will be evident in the following paper. The study examines and evaluates the characteristics of the NBA champions. As divisions and playoff teams increase, there is an increase in the probability that the champion originates from the mediocre category. Since it’s inception in 1947, the league has been mediocre and continues to this day. Why does a professional league allow any team with a less than 50% winning percentage into the playoffs? As long as the finances flow into the league, owners will not change the current algorithm. The objective of this paper is to determine if the regular season has meaning in finding an NBA champion. Statistical Analysis: The data originates from the NBA website. The following variables are part of the statistical analysis: Rank, the rank of a team relative to other teams in the league based on the regular season win-loss record; Winning Percentage of a team based on the regular season; Divisions, the number of divisions within the league and Playoff Teams, the number of playoff teams relative to a particular season. The following statistical applications are applied to the data: Pearson Product-Moment Correlation, Analysis of Variance, Factor and Regression analysis. Conclusion: The results indicate that the divisional structure and number of playoff teams results in a negative effect on the winning percentage of playoff teams. It also prevents teams with higher winning percentages from accessing the playoffs. Recommendations: 1. Teams that have a winning percentage greater than 1 standard deviation from the mean from the regular season will have access to playoffs. (Eliminates mediocre teams.) 2. Eliminate Divisions (Eliminates weaker teams from access to playoffs.) 3. Eliminate Conferences (Eliminates weaker teams from access to the playoffs.) 4. Have a balanced regular season schedule, (Reduces the number of regular season games, creates equilibrium, reduces bias) that will reduce the need for load management.Keywords: alignment, mediocrity, regression, z-score
Procedia PDF Downloads 130655 A Multi-Scale Approach for the Analysis of Fiber-Reinforced Composites
Authors: Azeez Shaik, Amit Salvi, B. P. Gautham
Abstract:
Fiber reinforced polymer resin composite materials are finding wide variety of applications in automotive and aerospace industry because of their high specific stiffness and specific strengths when compared to metals. New class of 2D and 3D textile and woven fabric composites offer excellent fracture toughens as they bridge the cracks formed during fracture. Due to complexity of their fiber architectures and its resulting composite microstructures, optimized design and analysis of these structures is very complicated. A traditional homogenization approach is typically used to analyze structures made up of these materials. This approach usually fails to predict damage initiation as well as damage propagation and ultimate failure of structure made up of woven and textile composites. This study demonstrates a methodology to analyze woven and textile composites by using the multi-level multi-scale modelling approach. In this approach, a geometric repetitive unit cell (RUC) is developed with all its constituents to develop a representative volume element (RVE) with all its constituents and their interaction modeled correctly. The structure is modeled based on the RUC/RVE and analyzed at different length scales with desired levels of fidelity incorporating the damage and failure. The results are passed across (up and down) the scales qualitatively as well as quantitatively from the perspective of material, configuration and architecture.Keywords: cohesive zone, multi-scale modeling, rate dependency, RUC, woven textiles
Procedia PDF Downloads 361654 Analysis of Farmer's Involvement in Public and Private Extension Services in Southwestern Nigeria
Authors: S. O. Ayansina, R. A. Oyeyinka, K. K. Bolarinwa
Abstract:
There is an increasing demand for a functional extension delivery services in Nigeria with a view to meet up with the food and fiber needs of the ever growing population of human and animal respectively. This study was designed to examine farmers’ involvement in public and private extension services in southwestern Nigeria, specifically to explore the farmers’ participation in the two types of organizations involved. It also evaluates the performances of personnel in the organizations. A multi-stage random sampling technique was used to select 30 respondents from each of the three selected organizations in Ogun, Osun and Oyo states in Southwestern Nigeria. Data was collected with interview schedule and analyzed both at descriptive and inferential levels. Kruskal Wallis one-way Analysis of variance was used to test the differences between the participation of beneficiaries who are farmers under the public and private extension services and the level of benefit accrued to them from the various extension organizations involved in the study. Results revealed that private extension organizations were performing better and were more preferred by the beneficiaries. Results of the tested hypotheses as shown by Kruskal Wallis test of difference (x2 = 0.709) S no significant difference between farmers’ participation in the extension services of public and private organizations but however showed significant difference (X2 =12.074) in the benefits achieved by respondents in the two organizations. These include: increased quantity of crop produced, farm income, skill acquisition, and improved education in private extension organizations. Based on this result, it could be inferred that beneficiaries generally preferred private extension organizations because of their effectiveness and vibrancy in programme administration. Public extension is therefore recommended for general overhauling and possibly privatization in order to cater for teeming population of farmers demanding for efficient and functional extension services to better their lots in production, processing and marketing of agricultural produce.Keywords: public and private involvement, extension services, farmers' participation
Procedia PDF Downloads 404653 Relationship between Employee Welfare Practices and Performance of Non-Governmental Organizations in Kenya
Authors: Protus A. Lumiti, Susan O. Wekesa, Mary Omondi
Abstract:
Performance is a key pillar to the accomplishment of the goals of all organizations, whether private, public or non- profit. Employees are the intellectual assets of the organization and they are an avenue to the achievement of competitive advantage. An employee welfare service in an organization is vital in fostering employee motivation and improving their productivity. In view of this, the main goal of this research was to determine the relationship between employee welfare practices and the performance of non-governmental organizations in Kenya. The study was guided by four objectives, namely: to establish, determine, evaluate and assess the relationship between employee welfare practices and the performance of non-governmental organizations in Kenya. The study utilized a survey design using both qualitative and quantitative approaches. In this study, a purposive, stratified and simple random sampling technique was used to arrive at a sample of 355 respondents who comprised senior managers, middle level managers and operational employees out of the targeted population of 14,283 employees of non-governmental organizations working in Nairobi County. The primary data collection tools were questionnaires supplemented by an interview schedule, while secondary data was obtained from reviewed journals, published books and articles. Data analysis was done using Statistical Packages for Social Sciences Software version 23. The study utilized multiple linear regression and a structural equation model. The findings of the study were that: employee welfare practices had a positive and significant relationship with the performance of Non-governmental organizations in Kenya. In addition, there was also a linear relationship between the independent variables and the dependent variable and the study concluded that there was a relationship between the predictor variable and the dependent variable of the study. The study recommended that management of No-governmental organization boards in Kenya should come up with a comprehensive policy document on employee welfare practices in order to enhance the performance of non-governmental organizations in Kenya.Keywords: employee, economic, performance, welfare
Procedia PDF Downloads 180652 Structural Testing and the Finite Element Modelling of Anchors Loaded Against Partially Confined Surfaces
Authors: Ali Karrech, Alberto Puccini, Ben Galvin, Davide Galli
Abstract:
This paper summarises the laboratory tests, numerical models and statistical approach developed to investigate the behaviour of concrete blocks loaded in shear through metallic anchors. This research is proposed to bridge a gap in the state of the art and practice related to anchors loaded against partially confined concrete surfaces. Eight concrete blocks (420 mm x 500 mm x 1000 mm) with 150 and/or 250 deep anchors were tested. The stainless-steel anchors of diameter 16 mm were bonded with HIT-RE 500 V4 injection epoxy resin and were subjected to shear loading against partially supported edges. In addition, finite element models were constructed to validate the laboratory tests and explore the influence of key parameters such as anchor depth, anchor distance from the edge, and compressive strength on the stability of the block. Upon their validation experimentally, the numerical results were used to populate, develop and interpret a systematic parametric study based on the Design of Experiment approach through the Box-Behnken design and Response Surface Methodology. An empirical model has been derived based on this approach, which predicts the load capacity with the desirable intervals of confidence.Keywords: finite element modelling, design of experiment, response surface methodology, Box-Behnken design, empirical model, interval of confidence, load capacity
Procedia PDF Downloads 24651 Resilience of Infrastructure Networks: Maintenance of Bridges in Mountainous Environments
Authors: Lorenza Abbracciavento, Valerio De Biagi
Abstract:
Infrastructures are key elements to ensure the operational functionality of the transport system. The collapse of a single bridge or, equivalently, a tunnel can leads an entire motorway to be considered completely inaccessible. As a consequence, the paralysis of the communications network determines several important drawbacks for the community. Recent chronicle events have demonstrated that ensuring the functional continuity of the strategic infrastructures during and after a catastrophic event makes a significant difference in terms of life and economical losses. Moreover, it has been observed that RC structures located in mountain environments show a worst state of conservation compared to the same typology and aging structures located in temperate climates. Because of its morphology, in fact, the mountain environment is particularly exposed to severe collapse and deterioration phenomena, generally: natural hazards, e.g. rock falls, and meteorological hazards, e.g. freeze-thaw cycles or heavy snows. For these reasons, deep investigation on the characteristics of these processes becomes of fundamental importance to provide smart and sustainable solutions and make the infrastructure system more resilient. In this paper, the design of a monitoring system in mountainous environments is presented and analyzed in its parts. The method not only takes into account the peculiar climatic conditions, but it is integrated and interacts with the environment surrounding.Keywords: structural health monitoring, resilience of bridges, mountain infrastructures, infrastructural network, maintenance
Procedia PDF Downloads 77650 Comparative Study on the Effect of Substitution of Li and Mg Instead of Ca on Structural and Biological Behaviors of Silicate Bioactive Glass
Authors: Alireza Arab, Morteza Elsa, Amirhossein Moghanian
Abstract:
In this study, experiments were carried out to achieve a promising multifunctional and modified silicate based bioactive glass (BG). The main aim of the study was investigating the effect of lithium (Li) and magnesium (Mg) substitution, on in vitro bioactivity of substituted-58S BG. Moreover, it is noteworthy to state that modified BGs were synthesized in 60SiO2–(36-x)CaO–4P2O5–(x)Li2O and 60SiO2–(36-x)CaO–4P2O5–(x)MgO (where x = 0, 5, 10 mol.%) quaternary systems, by sol-gel method. Their performance was investigated through different aspects such as biocompatibility, antibacterial activity as well as their effect on alkaline phosphatase (ALP) activity, and proliferation of MC3T3 cells. The antibacterial efficiency was evaluated against methicillin-resistant Staphylococcus aureus bacteria. To do so, CaO was substituted with Li2O and MgO up to 10 mol % in 58S-BGs and then samples were immersed in simulated body fluid up to 14 days and then, characterized by X-ray diffraction, Fourier transform infrared spectroscopy, inductively coupled plasma atomic emission spectrometry, and scanning electron microscopy. Results indicated that this modification led to a retarding effect on in vitro hydroxyapatite (HA) formation due to the lower supersaturation degree for nucleation of HA compared with 58s-BG. Meanwhile, magnesium revealed further pronounced effect. The 3-(4,5 dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) and ALP analysis illustrated that substitutions of both Li2O and MgO, up to 5 mol %, had increasing effect on biocompatibility and stimulating proliferation of the pre-osteoblast MC3T3 cells in comparison to the control specimen. Regarding to bactericidal efficiency, the substitution of either Li or Mg for Ca in the 58s BG composition led to statistically significant difference in antibacterial behaviors of substituted-BGs. Meanwhile, the sample containing 5 mol % CaO/Li2O substitution (BG-5L) was selected as a multifunctional biomaterial in bone repair/regeneration due to the improved biocompatibility, enhanced ALP activity and antibacterial efficiency among all of the synthesized L-BGs and M-BGs.Keywords: alkaline, alkaline earth, bioactivity, biomedical applications, sol-gel processes
Procedia PDF Downloads 108649 Rise in Public Interest in COVID-19 Symptoms and the Need for Proper Information: Insights from the Google Trends Analysis
Authors: Jaweriya Aftab, Madho Mal, Hamida Memon
Abstract:
The first case of coronavirus disease 2019 (COVID-19) in Pakistan was recorded on February 26th, 2020. While the country went through various phases of lockdowns, the importance of proper sensitization campaigns was highlighted by healthcare workers to combat misinformation. Past studies via Google trends analysis have shown a rise in public interest in multiple COVID-19-related symptoms as well as cardiovascular symptoms. As there is a paucity of data related to the trends in Pakistan, we conducted a retrospective analysis to bridge further information. Methods: As per the recommendations from past studies, a Google trend analysis was conducted for various symptoms, including ‘Fever’, ‘Chest Pain’, ‘Shortness of Breath’, and ‘Cough’ between 1st January 2019 to 31st December 2021. The trends in various search results were analyzed and modeled. Results: Our analysis found various rises in public interest in the various symptoms (fever, chest pain, shortness of breath, and cough) that correspond closely to the wave of the virus's spread in the country. Conclusion: Our study confirms similar trends in Pakistan as previously reported in studies from India, USA, and UK, whereby the public interest in various COVID-19 symptoms rose with the number of cases. This further highlights the need for a strong approach to combat misinformation during such a critical period.Keywords: covid, trend, Pakistan, public
Procedia PDF Downloads 36648 Rational Thinking and Forgiveness in Pakistan: The Role of Democratic Values and Mass Media Attitude
Authors: Muhammad Shoaib
Abstract:
Every society has a set of beliefs, norms, values, folkways, mores and laws. All the principles, customs, traditions and procedures of societies are directly or indirectly related to the religion of the society and changed with the passage of time by the mediation of democratic values attitudes and mass media influence. The main objective of the present study is to examine the effects of rational thinking values on forgiveness attitude by the mediation of democratic values and mass media attitude among family members. As many other developing settings, Pakistani society is undergoing a rapid and multifaceted social change, in which traditional thinking coexists and often clashes with modern thinking. Rational thinking attitude has great effects on the forgiveness attitude among family members as well as all the members of Pakistani society. For the present study 520 respondents were sampled from two urban areas of Punjab province; Lahore and Faisalabad, through proportionate random sampling technique. A survey method was used as a technique of data collection and an interview schedule was administered to collect information from the respondents. The results support that the net of other factors, favorable democratic values attitudes are positively associated rational thinking attitudes. The results also provide support that all other things equal, mass media attitudes also have a significant positive effect on rational thinking attitudes. Favorable democratic values attitudes have a significant net positive effect and the effect of mass media attitudes is positive and statistically highly significant. It shows that the effects of both democratic values attitudes and mass media attitudes diminish in magnitude when the rational thinking attitudes scale is included. However, the effect of democratic values remains highly significant. In comparison, the effect of mass media attitudes is only marginally significant.Keywords: rationality, forgiveness, democratic values, mass media, attitudes, Pakistan
Procedia PDF Downloads 367647 Lucilia Sericata Netrin-A: Secreted by Salivary Gland Larvae as a Potential to Neuroregeneration
Authors: Hamzeh Alipour, Masoumeh Bagheri, Tahereh Karamzadeh, Abbasali Raz, Kourosh Azizi
Abstract:
Netrin-A, a protein identified for conducting commissural axons, has a similar role in angiogenesis. In addition, studies have shown that one of the netrin-A receptors is expressed in the growing cells of small capillaries. It will be interesting to study this new group of molecules because their role in wound healing will become clearer in the future due to angiogenesis. The greenbottle blowfly Luciliasericata (L. sericata) larvae are increasingly used in maggot therapy of chronic wounds. This aim of this was the identification of moleculareatures of Netrin-A in L. sericata larvae. Larvae were reared under standard maggotarium conditions. The nucleic acid sequence of L. sericataNetrin-A (LSN-A) was then identified using Rapid Amplification of cDNA Ends (RACE) and Rapid Amplification of Genomic Ends (RAGE). Parts of the Netrin-A gene, including the middle, 3′-, and 5′-ends were identified, TA cloned in pTG19 plasmid, and transferred into DH5ɑ Escherichia coli. Each part was sequenced and assembled using SeqMan software. This gene structure was further subjected to in silico analysis. The DNA of LSN-A was identified to be 2407 bp, while its mRNA sequence was recognized as 2115 bp by Oligo0.7 software. It translated the Netrin-A protein with 704 amino acid residues. Its molecular weight is estimated to be 78.6 kDa. The 3-D structure ofNetrin-A drawn by SWISS-MODEL revealed its similarity to the Netrin-1 of humans with 66.8% identity. The LSN-A protein conduces to repair the myelin membrane in neuronal cells. Ultimately, it can be an effective candidate in neural regeneration and wound healing. Furthermore, our next attempt is to deplore recombinant proteins for use in medical sciences.Keywords: maggot therapy, netrin-A, RACE, RAGE, lucilia sericata
Procedia PDF Downloads 109646 Deubiquitinase USP35 Regulates Mitosis Progression by Blocking CDH1-Mediated Degradation of Aurora B.
Authors: Jinyoung Park, Eun Joo Song
Abstract:
Introduction: Deubiquitinating enzymes (DUBs) are proteases that cleave ubiquitin or ubiquitin-like modifications on substrates. Deubiquitination could regulate cellular physiology, such as signal transduction, DNA damage and repair, and cell cycle progression. Although more than 100 DUBs are encoded in the human and the importance of DUBs has been realized, the functions of most DUBs are unknown. This study aims to identify the molecular mechanism by which deubiquitinating enzyme USP35 regulates cell cycle progression for the first time. Methods: USP35 RNAi was mainly used to identify the function of USP35 in cell cycle progression. To find substrates of USP35, we analyzed protein-protein interaction using LC-MS. Several biological methods, such as ubiquitination assay, cell synchronization, immunofluorescence, and immunoprecipitation assay were used to investigate the exact mechanism by which USP35 affects successful completion of mitosis. Results: USP35 knockdown caused not only reduction of mitotic cell number but also induction of mitotic cells with abnormal spindle formation. Actually, cell proliferation was decreased by USP35 knockdown. Interestingly, we found that loss of USP35 decreased the stability and expression of Aurora B, a member of chromosomal passenger complex (CPC), and the phosphorylation of its substrate. Indeed, USP35 interacted with Aurora B and deubiquitinated it. In addition, USP35 knockdown induced abnormal localization of Aurora B in mitotic cells. Finally, CDH1-mediated ubiquitination of Aurora B level was rescued by USP35 overexpression, but not inactive form of USP35, USP35 C450A. Discussion: Our findings suggest that USP35 regulates Aurora B-mediated mitotic spindle assembly and G2-M transition by blocking CDH1-induced degradation of Aurora B.Keywords: USP35, HSP90, Aurora B, cell cycle progression
Procedia PDF Downloads 358645 A Primary Care Diagnosis of Middle-Aged Men with Oral Cancer Who Underwent Extensive Resection and Flap Repair: A Case Report
Authors: Ching-Yi Huang, Pi-Fen Cheng, Hui-Zhu Chen, Shi Ting Huang, Heng-Hua Wang
Abstract:
This is a case of oral cancer after extensive resection and modified right lateral neck lymph node dissection followed by reconstruction with a skin flap. The nursing period lasted From September 25 to October 3, 2017, through observation, interview, physical assessment, and medical record review, the author identified the following nursing problems: acute pain, impaired oral mucous membrane, and body image change. During the nursing period, the author provided individual and overall nursing care and established mutual trust through the use of empathy. Author listened and eased the patient's physical indisposition, such as wound pain, we use medications and acupuncture massage to relieve pain. However, for oral mucosa change caused by surgery, provide continuous and complete oral care and oral exercise training to improve oral mucosal healing and restore swallowing function. In the body-image changes, guided him to express his feeling after the body-image change, and enhanced support and from the family, and encouraged him to attend head and neck cancer survivor alliance which allowed the patient to accept the altered body image and reaffirm self-worth. Hopefully, through sharing this nursing experience will help to the nursing care quality of nursing care for oral cancer patients after extensive resection and modified right lateral neck lymph node dissection followed by reconstruction with a skin flap.Keywords: oral cancer, acute pain, impaired oral mucous membrane, body image change
Procedia PDF Downloads 187644 Assessment of E-Learning Facilities in Open and Distance Learning and Information Need by Students
Authors: Sabo Elizabeth
Abstract:
Electronic learning is increasingly popular learning approach in higher educational institutions due to vast growth of internet technology. This approach is important in human capital development. An investigation of open distance and e-learning facilities and information need by open and distance learning students was carried out in Jalingo, Nigeria. Structured questionnaires were administered to 70 registered ODL students of the NOUN. Information sourced from the respondents covered demographic, economic and institutional variables. Data collected for demographic variables were computed as frequency count and percentages. Assessment of the effectiveness of ODL facilities and information need among open and distance learning students was computed on a three or four point Likert Rating Scale. Findings indicated that there are more men compared to women. A large proportion of the respondents are married and there are more matured students in ODL compared to the youth. A high proportion of the ODL students obtained qualifications higher than the secondary school certificate. The proportion of computer literate ODL students was high, and large number of the students does not own a laptop computer. Inadequate e -books and reference materials, internet gadgets and inadequate books (hard copies) and reference material are factors that limit utilization of e-learning facilities in the study areas. Inadequate computer facilities and power back up caused inconveniences and delay in administering and use of e learning facilities. To a high extent, open and distance learning students needed information on university time table and schedule of activities, availability and access to books (hard and e-books) and reference materials. The respondents emphasized that contact with course coordinators via internet will provide a better learning and academic performance.Keywords: open and distance learning, information required, electronic books, internet gadgets, Likert scale test
Procedia PDF Downloads 325643 Challenges in the Material and Action-Resistance Factor Design for Embedded Retaining Wall Limit State Analysis
Authors: Kreso Ivandic, Filip Dodigovic, Damir Stuhec
Abstract:
The paper deals with the proposed 'Material' and 'Action-resistance factor' design methods in designing the embedded retaining walls. The parametric analysis of evaluating the differences of the output values mutually and compared with classic approach computation was performed. There is a challenge with the criteria for choosing the proposed calculation design methods in Eurocode 7 with respect to current technical regulations and regular engineering practice. The basic criterion for applying a particular design method is to ensure minimum an equal degree of reliability in relation to the current practice. The procedure of combining the relevant partial coefficients according to design methods was carried out. The use of mentioned partial coefficients should result in the same level of safety, regardless of load combinations, material characteristics and problem geometry. This proposed approach of the partial coefficients related to the material and/or action-resistance should aimed at building a bridge between calculations used so far and pure probability analysis. The measure to compare the results was to determine an equivalent safety factor for each analysis. The results show a visible wide span of equivalent values of the classic safety factors.Keywords: action-resistance factor design, classic approach, embedded retaining wall, Eurocode 7, limit states, material factor design
Procedia PDF Downloads 231642 Prime Graphs of Polynomials and Power Series Over Non-Commutative Rings
Authors: Walaa Obaidallah Alqarafi, Wafaa Mohammed Fakieh, Alaa Abdallah Altassan
Abstract:
Algebraic graph theory is defined as a bridge between algebraic structures and graphs. It has several uses in many fields, including chemistry, physics, and computer science. The prime graph is a type of graph associated with a ring R, where the vertex set is the whole ring R, and two vertices x and y are adjacent if either xRy=0 or yRx=0. However, the investigation of the prime graph over rings remains relatively limited. The behavior of this graph in extended rings, like R[x] and R[[x]], where R is a non-commutative ring, deserves more attention because of the wider applicability in algebra and other mathematical fields. To study the prime graphs over polynomials and power series rings, we used a combination of ring-theoretic and graph-theoretic techniques. This paper focuses on two invariants: the diameter and the girth of these graphs. Furthermore, the work discusses how the graph structures change when passing from R to R[x] and R[[x]]. In our study, we found that the set of strong zero-divisors of ring R represents the set of vertices in prime graphs. Based on this discovery, we redefined the vertices of prime graphs using the definition of strong zero divisors. Additionally, our results show that although the prime graphs of R[x] and R[[x]] are comparable to the graph of R, they have different combinatorial characteristics since these extensions contain new strong zero-divisors. In particular, we find conditions in which the diameter and girth of the graphs, as they expand from R to R[x] and R[[x]], do not change or do change. In conclusion, this study shows how extending a non-commutative ring R to R[x] and R[[x]] affects the structure of their prime graphs, particularly in terms of diameter and girth. These findings enhance the understanding of the relationship between ring extensions and graph properties.Keywords: prime graph, diameter, girth, polynomial ring, power series ring
Procedia PDF Downloads 18641 Branding Tourism Destinations; The Trending Initiatives for Edifice Image Choices of Foreign Policy
Authors: Mehtab Alam, Mudiarasan Kuppusamy, Puvaneswaran Kunaserkaran
Abstract:
The purpose of this paper is to bridge the gap and complete the relationship between tourism destinations and image branding as a choice of edifice foreign policy. Such options became a crucial component for individuals interested in leisure and travel activities. The destination management factors have been evaluated and analyzed using the primary and secondary data in a mixed-methods approach (quantitative sample of 384 and qualitative 8 semi-structured interviews at saturated point). The study chose the Environmental Management Accounting (EMA) and Image Restoration (IR) theories, along with a schematic diagram and an analytical framework supported by NVivo software 12, for two locations in Abbottabad, KPK, Pakistan: Shimla Hill and Thandiani. This incorporates the use of PLS-SEM model for assessing validity of data while SPSS for data screening of descriptive statistics. The results show that destination management's promotion of tourism has significantly improved Pakistan's state image. The use of institutional setup, environmental drivers, immigration, security, and hospitality as well as recreational initiatives on destination management is encouraged. The practical ramifications direct the heads of tourism projects, diplomats, directors, and policymakers to complete destination projects before inviting people to Pakistan. The paper provides the extent of knowledge for academic tourism circles to use tourism destinations as brand ambassadors.Keywords: tourism, management, state image, foreign policy, image branding
Procedia PDF Downloads 69