Search results for: Mohamad Esmaeil Jomeh
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 260

Search results for: Mohamad Esmaeil Jomeh

80 Hydrogen Production Through Thermocatalytic Decomposition of Methane Over Biochar

Authors: Seyed Mohamad Rasool Mirkarimi, David Chiaramonti, Samir Bensaid

Abstract:

Catalytic methane decomposition (CMD, reaction 4) is a one-step process for hydrogen production where carbon in the methane molecule is sequestered in the form of stable and higher-value carbon materials. Metallic catalysts and carbon-based catalysts are two major types of catalysts utilized for the CDM process. Although carbon-based catalysts have lower activity compared to metallic ones, they are less expensive and offer high thermal stability and strong resistance to chemical impurities such as sulfur. Also, it would require less costly separation methods as some of the carbon-based catalysts may not have an active metal component in them. Since the regeneration of metallic catalysts requires burning of the C on their surfaces, which emits CO/CO2, in some cases, using carbon-based catalysts would be recommended because regeneration can be completely avoided, and the catalyst can be directly used in other processes. This work focuses on the effect of biochar as a carbon-based catalyst for the conversion of methane into hydrogen and carbon. Biochar produced from the pyrolysis of poplar wood and activated biochar are used as catalysts for this process. In order to observe the impact of carbon-based catalysts on methane conversion, methane cracking in the absence and presence of catalysts for a gas stream with different levels of methane concentration should be performed. The results of these experiments prove conversion of methane in the absence of catalysts at 900 °C is negligible, whereas in the presence of biochar and activated biochar, significant growth has been observed. Comparing the results of the tests related to using char and activated char shows the enhancement obtained in BET surface area of the catalyst through activation leads to more than 10 vol.% methane conversion.

Keywords: hydrogen production, catalytic methane decomposition, biochar, activated biochar, carbon-based catalyts

Procedia PDF Downloads 81
79 Evaluation of Rheological Properties, Anisotropic Shrinkage, and Heterogeneous Densification of Ceramic Materials during Liquid Phase Sintering by Numerical-Experimental Procedure

Authors: Hamed Yaghoubi, Esmaeil Salahi, Fateme Taati

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The effective shear and bulk viscosity, as well as dynamic viscosity, describe the rheological properties of the ceramic body during the liquid phase sintering process. The rheological parameters depend on the physical and thermomechanical characteristics of the material such as relative density, temperature, grain size, and diffusion coefficient and activation energy. The main goal of this research is to acquire a comprehensive understanding of the response of an incompressible viscose ceramic material during liquid phase sintering process such as stress-strain relations, sintering and hydrostatic stress, the prediction of anisotropic shrinkage and heterogeneous densification as a function of sintering time by including the simultaneous influence of gravity field, and frictional force. After raw materials analysis, the standard hard porcelain mixture as a ceramic body was designed and prepared. Three different experimental configurations were designed including midpoint deflection, sinter bending, and free sintering samples. The numerical method for the ceramic specimens during the liquid phase sintering process are implemented in the CREEP user subroutine code in ABAQUS. The numerical-experimental procedure shows the anisotropic behavior, the complete difference in spatial displacement through three directions, the incompressibility for ceramic samples during the sintering process. The anisotropic shrinkage factor has been proposed to investigate the shrinkage anisotropy. It has been shown that the shrinkage along the normal axis of casting sample is about 1.5 times larger than that of casting direction, the gravitational force in pyroplastic deformation intensifies the shrinkage anisotropy more than the free sintering sample. The lowest and greatest equivalent creep strain occurs at the intermediate zone and around the central line of the midpoint distorted sample, respectively. In the sinter bending test sample, the equivalent creep strain approaches to the maximum near the contact area with refractory support. The inhomogeneity in Von-Misses, pressure, and principal stress intensifies the relative density non-uniformity in all samples, except in free sintering one. The symmetrical distribution of stress around the center of free sintering sample, cause to hinder the pyroplastic deformations. Densification results confirmed that the effective bulk viscosity was well-defined with relative density values. The stress analysis confirmed that the sintering stress is more than the hydrostatic stress from start to end of sintering time so, from both theoretically and experimentally point of view, the sintering process occurs completely.

Keywords: anisotropic shrinkage, ceramic material, liquid phase sintering process, rheological properties, numerical-experimental procedure

Procedia PDF Downloads 341
78 Polymorphisms of Calpastatin Gene and Its Association with Growth Traits in Indonesian Thin Tail Sheep

Authors: Muhammad Ihsan Andi Dagong, Cece Sumantri, Ronny Rachman Noor, Rachmat Herman, Mohamad Yamin

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Calpastatin involved in various physiological processes in the body such as the protein turnover, growth, fusion and mioblast migration. Thus, allegedly Calpastatin gene diversity (CAST) have an association with growth and potential use as candidate genes for growth trait. This study aims to identify the association between the genetic diversity of CAST gene with some growth properties such as body dimention (morphometric), body weight and daily weight gain in sheep. A total of 157 heads of Thin Tail Sheep (TTS) reared intensively for fattening purposes in the uniform environmental conditions. Overall sheep used were male, and maintained for 3 months. The parameters of growth properties were measured among others: body weight gain (ADG) (g/head / day), body weight (kg), body length (cm), chest circumference (cm), height (cm). All the sheep were genotyped by using PCR-SSCP (single strand conformational polymorphism) methods. CAST gene in locus fragment intron 5 - exon 6 were amplified with a predicted length of about 254 bp PCR products. Then the sheep were stratified based on their CAST genotypes. The result of this research showed that no association were found between the CAST gene variations with morphometric body weight, but there was a significant association with daily body weight gain (ADG) in sheep observed. CAST-23 and CAST-33 genotypes has higher average daily gain than other genotypes. CAST-23 and CAST-33 genotypes that carrying the CAST-2 and CAST-3 alleles potential to be used in the selection of the nature of the growth trait of the TTS sheep.

Keywords: body weight, calpastatin, genotype, growth trait, thin tail sheep

Procedia PDF Downloads 320
77 Physical Fitness Evaluation of Physical Education Teachers in Maktab Rendah Sains MARA (MRSM)

Authors: Mohamad Nizam Asmuni, Ahmad Naszeri Salleh, Yunus Adam, Azhar Yaacob, Mohd Hafiz Rosli, Muhamad Nazrul Hakim Abdullah

Abstract:

Physical Education teacher at the school should have good physical fitness to educate and guide students in the school. Currently, there are no standards for the level of physical fitness for teachers who teaches physical education at the school. Therefore, this research is to determine the level of physical fitness of teacher of Physical Education at Maktab Rendah Sains MARA (MRSM). A total of 28 samples (18 men and 10 women, age 33 ± 4.91), teachers of physical education at MRSM, were randomly selected to participate in this study. Height, weight, body fat percentage, body mass index (BMI) and other physical testing are measured and recorded. The results showed that the average of body mass index (BMI) for teachers of Physical Education is 25.9 ± 4:57. Body mass index (BMI) of teachers can be categorized as pre-obese based on World Health Organization (WHO) guidelines. Body fat percentage for male (age; 34.3 ± 5.13) and female (age; 30.9 ± 3.81) teachers is 24.7% ± 6.54 and 30.6% ± 6.28, respectively. Male teachers were categorized as overfat, however, female teachers were categorized as healthy based on body fat ranges for standard adults at NY Obesity Research Center. Bleep test results show that the average Bleep test is level 4 and shuttle 2; average VO2max was 27.5 ± 5.94 L/min. Physical fitness and performance of physical education teachers at MRSM is much lower compared to the rugby junior athlete in University Putra Malaysia (UPM). Therefore, physical fitness of teachers must be improved to ensure the physical education classes at MRSM could be done better.

Keywords: physical fitness, BMI, bleep test, obesity

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76 Analyzing Factors Impacting COVID-19 Vaccination Rates

Authors: Dongseok Cho, Mitchell Driedger, Sera Han, Noman Khan, Mohammed Elmorsy, Mohamad El-Hajj

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Since the approval of the COVID-19 vaccine in late 2020, vaccination rates have varied around the globe. Access to a vaccine supply, mandated vaccination policy, and vaccine hesitancy contribute to these rates. This study used COVID-19 vaccination data from Our World in Data and the Multilateral Leaders Task Force on COVID-19 to create two COVID-19 vaccination indices. The first index is the Vaccine Utilization Index (VUI), which measures how effectively each country has utilized its vaccine supply to doubly vaccinate its population. The second index is the Vaccination Acceleration Index (VAI), which evaluates how efficiently each country vaccinated its population within its first 150 days. Pearson correlations were created between these indices and country indicators obtained from the World Bank. The results of these correlations identify countries with stronger health indicators, such as lower mortality rates, lower age dependency ratios, and higher rates of immunization to other diseases, displaying higher VUI and VAI scores than countries with lesser values. VAI scores are also positively correlated to Governance and Economic indicators, such as regulatory quality, control of corruption, and GDP per capita. As represented by the VUI, proper utilization of the COVID-19 vaccine supply by country is observed in countries that display excellence in health practices. A country’s motivation to accelerate its vaccination rates within the first 150 days of vaccinating, as represented by the VAI, was largely a product of the governing body’s effectiveness and economic status, as well as overall excellence in health practises.

Keywords: data mining, Pearson correlation, COVID-19, vaccination rates and hesitancy

Procedia PDF Downloads 114
75 Microstructure and Hardness Changes on T91 Weld Joint after Heating at 560°C

Authors: Suraya Mohamad Nadzir, Badrol Ahmad, Norlia Berahim

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T91 steel has been used as construction material for superheater tubes in sub-critical and super critical boiler. This steel was developed with higher creep strength property as compared to conventional low alloy steel. However, this steel is also susceptible to materials degradation due to its sensitivity to heat treatment especially Post Weld Heat Treatment (PWHT) after weld repair process. Review of PWHT process shows that the holding temperature may different from one batch to other batch of samples depending on the material composition. This issue was reviewed by many researchers and one of the potential solutions is the development of weld repair process without PWHT. This process is possible with the use of temper bead welding technique. However, study has shown the hardness value across the weld joint with exception of PWHT is much higher compare to recommended hardness value. Based on the above findings, a study to evaluate the microstructure and hardness changes of T91 weld joint after heating at 560°C at varying duration was carried out. This study was carried out to evaluate the possibility of self-tempering process during in-service period. In this study, the T91 weld joint was heat-up in air furnace at 560°C for duration of 50 and 150 hours. The heating process was controlled with heating rate of 200°C/hours, and cooling rate about 100°C/hours. Following this process, samples were prepared for the microstructure examination and hardness evaluation. Results have shown full tempered martensite structure and acceptance hardness value was achieved after 50 hours heating. This result shows that the thin component such as T91 superheater tubes is able to self-tempering during service hour.

Keywords: T91, weld-joint, tempered martensite, self-tempering

Procedia PDF Downloads 379
74 The Effect of Endurance Training and Ginseng Consumption on VEGF and PDGF Plasma in Untrained Females

Authors: Barari Alireza, Seyed Hossein Alavi, Ghasemi Mohamad

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Objectives: VEGF and PDGF play central role in the processes of angiogenesis and vascular changes in most body tissues. The aim of the present study to determine effect of endurance training with ginseng on VEGF and PDGF levels is untrained female. Methods: Statistic society of this study was untraining male students of Azad University of Sari Branch in year of 2012-2013. Forty young untrained female (age 21.3 ± 0.90 year, height162.08±8.07cm , body weight 65.45± 7.6 kg and body mass index [BMI] 23.23 ± 2.64 kg/m2) were randomly divided into four groups: control(C), endurance(E), ginseng (G), endurance and ginseng (EG). Participants in training groups performed endurance training for 6 weeks and three sessions per week with 60-80% HRmax. Subjects perform endurance training and consumed ginseng for six weeks. Blood samples from the subjects before and after the test was performed. One wey ANOVA were used to test for differences between group and pair T-test were used for differences within groups. In all cases, P<0.05 was considered to be statistically significant. Results: A higher and significant Vo2 max was found in E and EG groups, while no change in other groups. BMI and Fat% were significantly decreased in EG group. No significant difference was found between and within groups in VEGF level. A higher and significant PDGF was only in endurance group, while there was significant reduction observed in G and EG groups. One-way ANOVA for PDGF showed significant difference between groups. Conclusion: The finding of the current study indicated that ginseng likely could through reducing of angiogenesis factors Such as VEGF and PDGF and reduced activity of tumor necrosis factor and inhibited inflammatory process.

Keywords: endurance, ginseng, VEGF, PDGF, untrained female

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73 Combined Effects of Thymol, Carvacrol and Packaging on the Shelf-Life of Marinated Chicken

Authors: Layal Karam, Rayan Roustom, Mohamad G. Abiad, Tahra El-Obeid, Ioannis N. Savvaidis

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The demand for marinated chicken worldwide, is continuously growing. To date, limited data on addition of active components of Essential Oils (EOs) to marinades for chicken preservation are available. The antimicrobial effect of carvacrol and thymol, added at 0.4 and 0.8% v/w to marinated fresh chicken, stored in air and under vacuum packaging (VP), for 21 days at 4°C, was examined. The samples were monitored for microbiological (total viable count (TVC), lactic acid bacteria (LAB), Brochothrix thermosphacta, Pseudomonas spp., total coliforms, Escherichia coli, yeasts and molds) and sensory attributes (odor characteristics). Our data supports that among the tested microorganisms, Pseudomonas spp., LAB and B. thermosphacta were the most dominant microbiota in the marinated chicken samples. Additionally, the use of active EOs components, especially the higher concentration (0.8% v/w) in combination with VP, retarded the growth of spoilage microbiota and resulted in a significant reduction of about 2.9-3.1 log cfu/g and a microbiological shelf-life extension of marinated chicken by > 6 days, as judged by TVC data. Interestingly, the combination of active components of EOs at the lower concentration (0.4% v/w) and packaging (air or vacuum) resulted in a significant sensorial shelf-life extension of 15 and >21 days, as compared to the controls’ shelf-life of 9 days. The results of our study demonstrated the potential of the active components, carvacrol and thymol, as natural effective antimicrobial hurdles to control the growth of spoilage microorganisms in marinated chicken meat.

Keywords: chicken, essential oils compounds, marination, meat spoilage, preservation

Procedia PDF Downloads 188
72 Effectiveness of Group Therapy Based on Acceptance and Commitment on Self-Criticism and Coping Mechanism in People with Addiction

Authors: Mohamad Reza Khodabakhsh

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Drug use and addiction are major biological, psychological, and social problems. In drug abuse treatment, it is important to pay attention to personality problems and coping methods of patients. Today, the third-wave treatments in psychotherapy emphasize people's awareness and acceptance of feelings and emotions, cognitions, and behaviors instead of challenging cognitions. For this reason, this research was conducted with the aim of investigating the effectiveness of group therapy based on acceptance and commitment to self-criticism and coping strategies of people with drug use disorder. This research was a quasi-experimental type of research (pre-test-post-test design with an unequal control group), and the statistical population of this research included all men with drug use disorder in Mashhad, 174 of whom among the 75 people eligible for this research, 30 of them were selected by available sampling method and randomly assigned to two experimental and control groups. In this research, Gilbert's self-criticism scale was used to measure self-criticism, and Andler and Barker's coping strategies questionnaire was used to measure coping strategies. Therapeutic intervention (treatment based on acceptance and commitment) was performed on the experimental group for eight sessions of 90 minutes, and then post-tests were taken from both groups, and multivariate analysis of covariance (MANCOVA) was used to analyze the data. The results showed that treatment based on acceptance and commitment significantly reduced self-criticism and improved coping strategies used by patients with drug use disorder (p>0.01). Therefore, treatment based on acceptance and commitment has been effective in reducing self-criticism and improving the coping strategies of patients with drug use disorder due to teaching clients to accept thoughts and conditions.

Keywords: treatment based on acceptance and commitment, self-criticism, coping strategies, addiction

Procedia PDF Downloads 88
71 Shariah Guideline on Value-Based Intermediation Implementation in the Light of Maqasid Shariah Analysis

Authors: Muhammad Izzam Bin Mohd Khazar, Ruqayyah Binti Mohamad Ali, Nurul Atiqah Binti Yusri

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Value-based intermediation (VBI) has been introduced by Bank Negara Malaysia (BNM) as the next strategic direction and growth driver for Islamic banking institutions. The aim of VBI is to deliver the intended outcome of Shariah through practices, conducts, and offerings that generate positive and sustainable impact to the economy, community and environment which is aligned to Maqasid Shariah in preserving the common interest of society by preventing harm and maximizing benefit. Hence, upon its implementation, VBI will experiment the current Shariah compliance treatment and revolutionise new policies and systems that can meritoriously entrench and convey the objectives of Shariah. However, discussion revolving VBI in the light of Maqasid analysis is still scarce hence further research needs to be undertaken. The idea of implementation of VBI vision into quantifiable Maqasid Shariah measurement is yet to be explored due to the nature of Maqasid that is variable. The contemporary scholars also have different views on the implementation of VBI. This paper aims to discuss on the importance of Maqasid Shariah in the current Islamic finance transactions by providing Shariah index measurement in the application of VBI. This study also intends to explore basic Shariah guidelines and parameters based on the objectives of Shariah; preservation of the five pillars (religion, life, progeny, intellect and wealth) with further elaboration on preservation of wealth under five headings: rawaj (circulation and marketability); wuduh (transparency); hifz (preservation); thabat (durability and tranquillity); and ‘adl (equity and justice). In alignment with these headings, Islamic finance can be innovated for VBI implementation, particularly in Maybank Islamic being a significant leader in the IFI market.

Keywords: Islamic Financial Institutions, Maqasid Index, Maqasid Shariah, sustainability, value-based intermediation

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70 Novel Liposomal Nanocarriers For Long-term Tumor Imaging

Authors: Mohamad Ahrari, Kayvan Sadri, Mahmoud Reza Jafari

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PEGylated liposomes have a smaller volume of distribution and decreased clearance, consequently, due to their more prolonged presence in bloodstream and maintaining their stability during this period, these liposomes can be applied for imaging tumoral sites. The purpose of this study is to develop an appropriate radiopharmaceutical agent in long-term imaging for improved diagnosis and evaluation of tumors. In this study, liposomal formulations encapsulating albumin is synthesized by solvent evaporation method along with homogenization, and their characteristics were assessed. Then these liposomes labeled by Philips method and the rate of stability of labeled liposomes in serum, and ultimately the rate of biodistribution and gamma scintigraphy in C26-colon carcinoma tumor-bearing mice, were studied. The result of the study of liposomal characteristics displayed that capable of accumulating in tumor sites based of EPR phenomenon. these liposomes also have high stability for maintaining encapsulated albumin in a long time. In the study of biodistribution of these liposomes in mice, they accumulated more in the kidney, liver, spleen, and tumor sites, which, even after clearing formulations in the bloodstream, they existed in high levels in these organs up to 96 hours. In gamma scintigraphy also, organs with high activity accumulation from early hours up to 96 hours were visible in the form of hot spots. concluded that PEGylated liposomal formulation encapsulating albumin can be labeled with In-Oxine, and obtained stabilized formulation for long-term imaging, that have more favorable conditions for the evaluation of tumors and it will cause early diagnosis of tumors.

Keywords: nano liposome, 111In-oxine, imaging, biodistribution, tumor

Procedia PDF Downloads 113
69 Effectiveness of a Malaysian Workplace Intervention Study on Physical Activity Levels

Authors: M. Z. Bin Mohd Ghazali, N. C. Wilson, A. F. Bin Ahmad Fuad, M. A. H. B. Musa, M. U. Mohamad Sani, F. Zulkifli, M. S. Zainal Abidin

Abstract:

Physical activity levels are low in Malaysia and this study was undertaken to determine if a four week work-based intervention program would be effective in changing physical activity levels. The study was conducted in a Malaysian Government Department and had three stages: baseline data collection, four-week intervention and two-month post intervention data collection. During the intervention and two-month post intervention phases, physical activity levels (determined by a pedometer) and basic health profiles (BMI, abdominal obesity, blood pressure) were measured. Staff (58 males, 47 females) with an average age of 33 years completed baseline data collection. Pedometer steps averaged 7,102 steps/day at baseline, although male step counts were significantly higher than females (7,861 vs. 6114). Health profiles were poor: over 50% were overweight/obese (males 66%, females 40%); hypertension (males 23%, females 6%); excess waist circumference (males 52%, females 17%). While 86 staff participated in the intervention, only 49 regularly reported their steps. There was a significant increase (17%) in average daily steps from 8,965 (week 1) to 10,436 (week 4). Unfortunately, participation in the intervention program was avoided by the less healthy staff. Two months after the intervention there was no significant difference in average steps/day, despite the fact that 89% of staff reporting they planned to make long-term changes to their lifestyle. An unexpected average increase of 2kg in body weight occurred in participants, although this was less than the 5.6kg in non-participants. A number of recommendations are made for future interventions, including the conclusion that pedometers were a useful tool and popular with participants.

Keywords: pedometers, walking, health, intervention

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68 The Effect of Feedstock Type and Slow Pyrolysis Temperature on Biochar Yield from Coconut Wastes

Authors: Adilah Shariff, Nur Syairah Mohamad Aziz, Norsyahidah Md Saleh, Nur Syuhada Izzati Ruzali

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The first objective of this study is to investigate the suitability of coconut frond (CF) and coconut husk (CH) as feedstocks using a laboratory-scale slow pyrolysis experimental setup. The second objective is to investigate the effect of pyrolysis temperature on the biochar yield. The properties of CF and CH feedstocks were compared. The properties of the CF and CH feedstocks were investigated using proximate and elemental analysis, lignocellulosic determination, and also thermogravimetric analysis (TGA). The CF and CH feedstocks were pyrolysed at 300, 400, 500, 600 and 700 °C for 2 hours at 10 °C/min heating rate. The proximate analysis showed that CF feedstock has 89.96 mf wt% volatile matter, 4.67 mf wt% ash content and 5.37 mf wt% fixed carbon. The lignocelluloses analysis showed that CF feedstock contained 21.46% lignin, 39.05% cellulose and 22.49% hemicelluloses. The CH feedstock contained 84.13 mf wt% volatile matter, 0.33 mf wt% ash content, 15.54 mf wt% fixed carbon, 28.22% lignin, 33.61% cellulose and 22.03% hemicelluloses. Carbon and oxygen are the major component of the CF and CH feedstock compositions. Both of CF and CH feedstocks contained very low percentage of sulfur, 0.77% and 0.33%, respectively. TGA analysis indicated that coconut wastes are easily degraded. It may be due to their high volatile content. Between the temperature ranges of 300 and 800 °C, the TGA curves showed that the weight percentage of CF feedstock is lower than CH feedstock by 0.62%-5.88%. From the D TGA curves, most of the weight loss occurred between 210 and 400 °C for both feedstocks. The maximum weight loss for both CF and CH are 0.0074 wt%/min and 0.0061 wt%/min, respectively, which occurred at 324.5 °C. The yield percentage of both CF and CH biochars decreased significantly as the pyrolysis temperature was increased. For CF biochar, the yield decreased from 49.40 wt% to 28.12 wt% as the temperature increased from 300 to 700 °C. The yield for CH biochars also decreased from 52.18 wt% to 28.72 wt%. The findings of this study indicated that both CF and CH are suitable feedstock for slow pyrolysis of biochar.

Keywords: biochar, biomass, coconut wastes, slow pyrolysis

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67 Bifurcations of a System of Rotor-Ball Bearings with Waviness and Squeeze Film Dampers

Authors: Sina Modares Ahmadi, Mohamad Reza Ghazavi, Mandana Sheikhzad

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Squeeze film damper systems (SFD) are often used in machines with high rotational speed to reduce non-periodic behavior by creating external damping. These types of systems are frequently used in aircraft gas turbine engines. There are some structural parameters which are of great importance in designing these kinds of systems, such as oil film thickness, C, and outer race mass, mo. Moreover, there is a crucial parameter associated with manufacturing process, under the title of waviness. Geometric imperfections are often called waviness if its wavelength is much longer than Hertzian contact width which is a considerable source of vibration in ball bearings. In this paper, a system of a flexible rotor and two ball bearings with floating ring squeeze film dampers and consideration of waviness has been modeled and solved by a numerical integration method, namely Runge-Kutta method to investigate the dynamic response of the system. The results show that by increasing the number of wave lobes, which is due to inappropriate manufacturing, non- periodic and chaotic behavior increases. This result reveals the importance of manufacturing accuracy. Moreover, as long as C< 1.5×10-4 m, by increasing the oil film thickness, unwanted vibrations and non-periodic behavior of the system have been reduced, On the other hand, when C>1.5×10-4 m, increasing the outer oil film thickness results in the increasing chaotic and non-periodic responses. This result shows that although the presence of oil film results in reduction the non-periodic and chaotic behaviors, but the oil film has an optimal thickness. In addition, with increasing mo, the disc displacement amplitude increases. This result reveals the importance of utilizing light materials in manufacturing the squeeze film dampers.

Keywords: squeeze-film damper, waviness, ball bearing, bifurcation

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66 Investigation of Boll Properties on Cotton Picker Machine Performance

Authors: Shahram Nowrouzieh, Abbas Rezaei Asl, Mohamad Ali Jafari

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Cotton, as a strategic crop, plays an important role in providing human food and clothing need, because of its oil, protein, and fiber. Iran has been one of the largest cotton producers in the world in the past, but unfortunately, for economic reasons, its production is reduced now. One of the ways to reduce the cost of cotton production is to expand the mechanization of cotton harvesting. Iranian farmers do not accept the function of cotton harvesters. One reason for this lack of acceptance of cotton harvesting machines is the number of field losses on these machines. So, the majority of cotton fields are harvested by hand. Although the correct setting of the harvesting machine is very important in the cotton losses, the morphological properties of the cotton plant also affect the performance of cotton harvesters. In this study, the effect of some cotton morphological properties such as the height of the cotton plant, number, and length of sympodial and monopodial branches, boll dimensions, boll weight, number of carpels and bracts angle were evaluated on the performance of cotton picker. In this research, the efficiency of John Deere 9920 spindle Cotton picker is investigated on five different Iranian cotton cultivars. The results indicate that there was a significant difference between the five cultivars in terms of machine harvest efficiency. Golestan cultivar showed the best cotton harvester performance with an average of 87.6% of total harvestable seed cotton and Khorshid cultivar had the least cotton harvester performance. The principal component analysis showed that, at 50.76% probability, the cotton picker efficiency is affected by the bracts angle positively and by boll dimensions, the number of carpels and the height of cotton plants negatively. The seed cotton remains (in the plant and on the ground) after harvester in PCA scatter plot were in the same zone with boll dimensions and several carpels.

Keywords: cotton, bract, harvester, carpel

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65 The Effectiveness of Sleep Behavioral Interventions during the Third Trimester of Pregnancy on Sleep Quality and Postpartum Depression in a Randomized Clinical Controlled Trial

Authors: Somaye Ghafarpour, Kamran Yazdanbakhsh, Mohamad Reza Zarbakhsh, Simin Hosseinian, Samira Ghafarpour

Abstract:

Unsatisfactory sleep quality is one of the most common complications of pregnancy, which can predispose mothers to postpartum depression, requiring implementing effective psychological interventions to prevent and modify behaviors accentuating sleep problems. This study was a randomized clinical controlled trial with a pre-test/post-test design aiming to investigate the effectiveness of sleep behavioral interventions during the third trimester of pregnancy on sleep quality and postpartum depression. A total of 50 pregnant mothers in the 26-30 weeks of pregnancy suffering from sleep problems (based on the score obtained from the Pittsburgh Sleep Questionnaire) were randomized into two groups (control and intervention, n= 25 per group). The data were collected using interviews, the Pittsburgh Sleep Quality Index (PSQI), and the Edinburgh Postnatal Depression Scale (EPDS) were used. The participants in the intervention group received eight 60-minute sessions of combinational training for behavioral therapy techniques. At the end of the intervention and four weeks after delivery, sleep quality and postpartum depression were evaluated. Considering that the Kolmogorov Smirnov test confirmed the normal distribution of the data, the independent t-test and analysis of covariance were used to analyze the data, showing that the behavioral interventions were effective on the overall sleep quality after delivery (p=0.001); however, no statistically significant effects were observed on postpartum depression, the sub-scales of sleep disorders, and daily functioning (p>0.05). Considering the potential effectiveness of behavioral interventions in improving sleep quality and alleviating insomnia symptoms, it is recommended to implement such measures as an effective intervention to prevent or treat these problems during prenatal and postnatal periods.

Keywords: behavioral interventions, sleep quality, postpartum depression, pregnancy, delivery

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64 The University-Industry Relationships in Sweden and Iran: A Critical Comparative Study

Authors: Sepideh Nikounejad, Mostafa Ghaderi, Nematollah Azizi, Per-Olof Thang, Mohamad Reza Neyestani

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From an educational perspective, an effective and efficient relationship between university and industry can be considered as an important means by which not only both sides are improved but also it brings many advantages and benefits for both parties. It means more specifically, mutual collaboration between universities and industry can not only reduce youth unemployment, but it can improve the quality of teaching and learning in higher education settings while providing more qualified people to industrial enterprises. Indeed the lack of effective interaction between Iranian universities and industry has confronted the country and created many challenges include in increasing number of unskillful and unemployed graduates. However, in order to suggest appropriate practical strategies, it is very important to see how this issue has been tackled by Swedish universities, which have had a good background in this collaboration and how they are connected to the industry in particular and labour market in general. The research aims to study and compare the mechanisms, processes, and policies of the current model in the relationships between university and industry in Iran and Sweden. As a qualitative study, grounded theory was applied. Data were collected via semi-structured interviews. Participants were selected purposefully and by the snowball sampling method. The findings indicate that despite reported needs from both sides for close collaborations between universities and industries in Iran, current policies and practices, including internship, laboratory, and financial support, need to be revised critically. However, in light of our findings on the Swedish policies and practices for linking universities and industries, some practical strategies will be suggested for the Iranian higher education context. In conclusion, cooperation models between universities and industries in Iran and Sweden will be described.

Keywords: cooperation, higher education, industry, comparative

Procedia PDF Downloads 133
63 A Cloud-Based Mobile Auditing Tools for Muslim-Friendly Hospitality Services

Authors: Mohd Iskandar Illyas Tan, Zuhra Junaida Mohamad Husny, Farawahida Mohd Yusof

Abstract:

The potentials of Muslim-friendly hospitality services bring huge opportunities to operators (hoteliers, tourist guides, and travel agents), especially among the Muslim countries. In order to provide guidelines that facilitate the operations among these operators, standards and manuals have been developing by the authorities. Among the challenges is the applicability and complexity of the standard to be adopted in the real world. Mobile digital technology can be implemented to overcome those challenges. A prototype has been developed to help operators and authorities to assess their readiness in complying with MS2610:2015. This study analyzes the of mobile digital technology characteristics that are suitable for the user in conducting sharia’ compliant hospitality audit. A focus group study was conducted in the state of Penang, Malaysia that involves operators (hoteliers, tourist guide, and travel agents) as well as agencies (Islamic Tourism Center, Penang Islamic Affairs Department, Malaysian Standard) that involved directly in the implementation of the certification. Both groups were given the 3 weeks to test and provide feedback on the usability of the mobile applications in order to conduct an audit on their readiness towards the Muslim-friendly hospitality services standard developed by the Malaysian Standard. The feedbacks were analyzed and the overall results show that three criteria (ease of use, completeness and fast to complete) show the highest responses among both groups for the mobile application. This study provides the evidence that the mobile application development has huge potentials to be implemented by the Muslim-friendly hospitality services operator and agencies.

Keywords: hospitality, innovation, audit, compliance, mobile application

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62 Failure to React Positively to Flood Early Warning Systems: Lessons Learned by Flood Victims from Flash Flood Disasters: the Malaysia Experience

Authors: Mohamad Sukeri Khalid, Che Su Mustaffa, Mohd Najib Marzuki, Mohd Fo’ad Sakdan, Sapora Sipon, Mohd Taib Ariffin, Shazwani Shafiai

Abstract:

This paper describes the issues relating to the role of the flash flood early warning system provided by the Malaysian Government to the communities in Malaysia, specifically during the flash flood disaster in the Cameron Highlands, Malaysia. Normally, flash flood disasters can occur as a result of heavy rainfall in an area, and that water may possibly cause flooding via streams or narrow channels. For this study, the flash flood disaster in the Cameron Highlands occurred on 23 October 2013, and as a result the Sungai Bertam overflowed after the release of water from the Sultan Abu Bakar Dam. This release of water from the dam caused flash flooding which led to damage to properties and also the death of residents and livestock in the area. Therefore, the effort of this study is to identify the perceptions of the flash flood victims on the role of the flash flood early warning system. For the purposes of this study, data collection was gathered from those flood victims who were willing to participate in this study through face-to-face interviews. This approach helped the researcher to glean in-depth information about their feeling and perceptions on the role of the flash flood early warning system offered by the government. The data were analysed descriptively and the findings show that the respondents of 22 flood victims believe strongly that the flash flood early warning system was confusing and dysfunctional, and communities had failed to response positively to it. Therefore, most of the communities were not well prepared for the releasing of water from the dam that caused property damage and 3 people were killed in Cameron Highland flash flood disaster.

Keywords: communities affected, disaster management, early warning system, flash flood disaster

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61 Effects of Destination Image, Perceived Value, Tourist Satisfaction and Service Quality on Destination Loyalty

Authors: Mahadzirah Mohamad, Nur Izzati Ab Ghani

Abstract:

Worldwide, tourism sustained growth and remained to be one of the fast-growing sectors. Malaysia tourism industry experienced an unstable and declining pattern of international tourist arrival’s growth rate. The situation suggested that the industry was competitive and denoted the need to study factors that influence tourist loyalty. The primary purpose of this study was to develop a model that examined how destination image, perceived value, service quality and tourist satisfaction affect destination loyalty. The study was conducted at the Kuala Lumpur International Airport and Kota Kinabalu International Airport. The respondents were international tourists from United Kingdom and Australia and they were selected using simple random sampling method. A total of 337 respondents were subjected to data analysis using structural equation modelling. The study uncovered that perceived value and destination image was highly correlated and the model suggested that these constructs should be treated as one construct. The construct was labelled as overall destination image. Overall image had significant direct effect on service quality, satisfaction and loyalty. Service quality had a significant indirect effect on loyalty through satisfaction as a moderating variable. However, satisfaction had no mediating effect on the relationship between overall destination image and loyalty. The study suggested that more efforts should be focused on portraying the image of experiencing joy with many interesting natural scenic places to see whilst on a holiday to Malaysia. In addition, the destination management office should promote tourist visiting to Malaysia would enjoy quality service related to accommodation, information facilities, health, and shopping. Tourist satisfaction empirically proved to be an important construct that influenced destination loyalty. This study contributed to the extended knowledge that postulated overall image of a destination was measured by perceived value and destination image.

Keywords: destination image, destination loyalty, structural equation modelling, tourist satisfaction

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60 Finite Element Modeling of Aortic Intramural Haematoma Shows Size Matters

Authors: Aihong Zhao, Priya Sastry, Mark L Field, Mohamad Bashir, Arvind Singh, David Richens

Abstract:

Objectives: Intramural haematoma (IMH) is one of the pathologies, along with acute aortic dissection, that present as Acute Aortic Syndrome (AAS). Evidence suggests that unlike aortic dissection, some intramural haematomas may regress with medical management. However, intramural haematomas have been traditionally managed like acute aortic dissections. Given that some of these pathologies may regress with conservative management, it would be useful to be able to identify which of these may not need high risk emergency intervention. A computational aortic model was used in this study to try and identify intramural haematomas with risk of progression to aortic dissection. Methods: We created a computational model of the aorta with luminal blood flow. Reports in the literature have identified 11 mm as the radial clot thickness that is associated with heightened risk of progression of intramural haematoma. Accordingly, haematomas of varying sizes were implanted in the modeled aortic wall to test this hypothesis. The model was exposed to physiological blood flows and the stresses and strains in each layer of the aortic wall were recorded. Results: Size and shape of clot were seen to affect the magnitude of aortic stresses. The greatest stresses and strains were recorded in the intima of the model. When the haematoma exceeded 10 mm in all dimensions, the stress on the intima reached breaking point. Conclusion: Intramural clot size appears to be a contributory factor affecting aortic wall stress. Our computer simulation corroborates clinical evidence in the literature proposing that IMH diameter greater than 11 mm may be predictive of progression. This preliminary report suggests finite element modelling of the aortic wall may be a useful process by which to examine putative variables important in predicting progression or regression of intramural haematoma.

Keywords: intramural haematoma, acute aortic syndrome, finite element analysis,

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59 The Causality between Corruption and Economic Growth in MENA Countries: A Dynamic Panel-Data Analysis

Authors: Nour Mohamad Fayad

Abstract:

Complex and extensively researched, the impact of corruption on economic growth seems to be intricate. Many experts believe that corruption reduces economic development. However, counterarguments have suggested that corruption either promotes growth and development or has no significant impact on economic performance. Clearly, there is no consensus in the economics literature regarding the possible relationship between corruption and economic development. Corruption's complex and clandestine nature, which makes it difficult to define and measure, is one of the obstacles that must be overcome when investigating its effect on an economy. In an attempt to contribute to the ongoing debate, this study examines the impact of corruption on economic growth in the Middle East and North Africa (MENA) region between 2000 and 2021 using a Customized Corruption Index-CCI and panel data on MENA countries. These countries were selected because they are understudied in the economic literature, and despite the World Bank's recent emphasis on corruption in the developing world, the MENA countries have received little attention. The researcher used Cobb-Douglas functional form to test corruption in MENA using a customized index known as Customized Corruption Index-CCI to track corruption over almost 20 years, then used the dynamic panel data. The findings indicate that there is a positive correlation between corruption and economic growth, but this is not consistent across all MENA nations. First, the relatively recent lack of data from MENA nations. This issue is related to the inaccessibility of data for many MENA countries, particularly regarding the returns on resources, private malfeasance, and other variables in Gulf countries. In addition, the researcher encountered several restrictions, such as electricity and internet outages, due to the fact that he is from Lebanon, a country whose citizens have endured difficult living conditions since the Lebanese crisis began in 2019. Demonstrating a customized index known as Customized Corruption Index-CCI that suits the characteristics of MENA countries to peculiarly measure corruption in this region, the outcome of the Customized Corruption Index-CCI is then compared to the Corruption Perception Index-CPI and Control of Corruption from World Governance Indicator-CC from WGI.

Keywords: corruption, economic growth, corruption measurements, empirical review, impact of corruption

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58 Challenges in Implementing the Inculcation of Noble Values During Teaching by Primary Schools Teachers in Peninsular Malaysia

Authors: Mohamad Khairi Haji Othman, Mohd Zailani Mohd Yusoff, Rozalina Khalid

Abstract:

The inculcation of noble values in teaching and learning is very important, especially to build students with good characters and values. Therefore, the purpose of this research is to identify the challenges of implementing the inculcation of noble values in teaching in primary schools. This study was conducted at four North Zone Peninsular Malaysia schools. This study was used a qualitative approach in the form of case studies. The qualitative approach aims at gaining meaning and a deep understanding of the phenomenon studied from the perspectives of the study participants and not intended to make the generalization. The sample in this study consists of eight teachers who teach in four types of schools that have been chosen purposively. The method of data collection is through semi-structured interviews used in this study. The comparative method is continuously used in this study to analyze the primary data collected. The study found that the main challenges faced by teachers were students' problems and class control so that teachers felt difficult to the inculcation of noble values in teaching. In addition, the language challenge is difficult for students to understand. Similarly, peers are also challenging because students are more easily influenced by friends rather than listening to teachers' instructions. The last challenge was the influence of technology and mass media electronic more widespread. The findings suggest that teachers need to innovate in order to assist the school in inculcating religious and moral education towards the students. The school through guidance and counseling teachers can also plan some activities that are appropriate to the student's present condition. Through this study, teachers and the school should work together to develop the values of students in line with the needs of the National Education Philosophy that wishes to produce intelligent, emotional, spiritual, intellectual and social human capital.

Keywords: challenges, implementation, inculcation, noble values

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57 Utilizing Bario Rice, a Natural Red-Pigmented Rice from Sarawak, Malaysia, in the Development of Gluten-Free Bread

Authors: Macdalyna Esther Ronie, Hasmadi Mamat, Ahmad Hazim Abdul Aziz, Mohamad Khairi Zainol

Abstract:

Current trends in gluten-free food development are increasingly leaning towards the utilization of pigmented rice flour, with a particular focus on Bario Merah Sederhana (BMS), a red-pigmented rice native to Sarawak, Malaysia. This study delves into the evaluation of the nutritional, textural, and sensory attributes of gluten-free rice bread produced from a blend of BMS rice flour and potato starch. The resulting samples are denoted as F1 (100% BMS rice flour), F2 (90% BMS rice flour and 10% potato starch), F3 (80% BMS rice flour and 20% potato starch), and F4 (70% BMS rice flour and 30% potato starch). Comparatively, these gluten-free rice bread formulations exhibit higher levels of ash and crude fiber, along with lower carbohydrate content when juxtaposed with conventional wheat bread. Notably, the crude protein content of the rice bread diminishes significantly (p<0.05) as the proportion of rice flour decreases, primarily due to the higher protein content found in wheat flour. The crumb of the rice bread appears darker owing to the red pigment in the rice flour, while the crust is lighter than that of the control sample, possibly attributable to a reduced Maillard reaction. Among the various rice bread formulations, F4 stands out with the least dough and bread hardness, accompanied by the highest levels of stickiness and springiness in both dough and bread, respectively. In sensory evaluations, wheat bread garners the highest rating (p<0.05). However, within the realm of rice breads, F4 emerges as a viable and acceptable formulation, as indicated by its commendable scores in color (7.03), flavor (5.73), texture (6.03), and overall acceptability (6.18). These findings underscore the potential of BMS in the creation of gluten-free rice breads, with the formulation consisting of 70% rice flour and 30% potato starch emerging as a well-received and suitable option.

Keywords: gluten-free bread, bario rice, proximate composition, sensory evaluation

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56 Detection of Cryptosporidium Oocysts by Acid-Fast Staining Method and PCR in Surface Water from Tehran, Iran

Authors: Mohamad Mohsen Homayouni, Niloofar Taghipour, Ahmad Reza Memar, Niloofar Khalaji, Hamed Kiani, Seyyed Javad Seyyed Tabaei

Abstract:

Background and Objective: Cryptosporidium is a coccidian protozoan parasite; its oocysts in surface water are a global health problem. Due to the low number of parasites in the water resources and the lack of laboratory culture, rapid and sensitive method for detection of the organism in the water resources is necessarily required. We applied modified acid-fast staining and PCR for the detection of the Cryptosporidium spp. and analysed the genotypes in 55 samples collected from surface water. Methods: Over a period of nine months, 55 surface water samples were collected from the five rivers in Tehran, Iran. The samples were filtered by using cellulose acetate membrane filters. By acid fast method, initial identification of Cryptosporidium oocyst were carried out on surface water samples. Then, nested PCR assay was designed for the specific amplification and analysed the genotypes. Results: Modified Ziehl-Neelsen method revealed 5–20 Cryptosporidium oocysts detected per 10 Liter. Five out of the 55 (9.09%) surface water samples were found positive for Cryptosporidium spp. by Ziehl-Neelsen test and seven (12.7%) were found positive by nested PCR. The staining results were consistent with PCR. Seven Cryptosporidium PCR products were successfully sequenced and five gp60 subtypes were detected. Our finding of gp60 gene revealed that all of the positive isolates were Cryptosporidium parvum and belonged to subtype families IIa and IId. Conclusion: Our investigations were showed that collection of water samples were contaminated by Cryptosporidium, with potential hazards for the significant health problem. This study provides the first report on detection and genotyping of Cryptosporidium species from surface water samples in Iran, and its result confirmed the low clinical incidence of this parasite on the community.

Keywords: Cryptosporidium spp., membrane filtration, subtype, surface water, Iran

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55 Satureja bachtiarica Bunge Induce Apoptosis via Mitochondrial Intrinsic Pathway and G1 Cell Cycle Arrest

Authors: Hamed Karimian, Noraziah Nordin, Mohamad Ibrahim Noordin, Syam Mohan, Mahboubeh Razavi, Najihah Mohd Hashim, Happipah Mohd Ali

Abstract:

Satureja bachtiarica Bunge is a perennial medicinal plant belonging to the Lamiaceae family and endemic species in Iran. Satureja bachtiarica Bunge with the local name of Marzeh koohi is edible vegetable use as flavoring agent, anti-bacterial and to relieve cough and indigestion. In this study, the anti-cancer effect of Satureja bachtiarica Bunge on the MDA-MB-231 cell line as an Breast cancer cell model has been analyzed for the first time. Satureja bachtiarica Bunge was extracted using different solvents in the order of increasing polarity. Cytotoxicity activity of hexane extract of Satureja bachtiarica Bunge (SBHE) was observed using MTT assay. Acridine orange/Propidium iodide staining was used to detect early apoptosis; Annexin-V-FITC assay was carried out to observe the detection of cell-surface Phosphatidylserine (PS), with Annexin-Vserving as a marker for apoptotic cells. Caspase 3/7, 8 and-9 assays showed significantly activation of caspase-9 where lead intrinsic mitochondrial pathway. Bcl-2/Bax expressions and cell cycle arrest were also investigated. SBHE had exhibited significantly higher cytotoxicity against MDA-MB-231 Cell line compare to other cell lines. A significant increase in chromatin condensation in the cell nucleus was observed by fluorescence analysis. Treatment of MDA-MB-231 cells with SBHE encouraged apoptosis, by down-regulating Bcl-2 and up-regulating Bax, which lead the activation of caspase 9. Moreover, SBHE treatment significantly arrested MDA-MB-231 cells in the G1 phase. Together, the results presented in this study demonstrated that SBHE inhibited the proliferation of MDA-MB-231 cells, leading cell cycle arrest and programmed cell death, which was confirmed to be through the mitochondrial pathway.

Keywords: Satureja bachtiarica Bunge, MDA-MB-231, apoptosis, annexin-V, cell cycle

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54 A Quantitative Model for Replacement of Medical Equipment Based on Technical and Environmental Factors

Authors: Ghadeer Mohammad Said El-Sheikh, Samer Mohamad Shalhoob

Abstract:

Medical equipment operation state is a valid reflection of health care organizations' performance, where such equipment highly contributes to the quality of healthcare services on several levels in which quality improvement has become an intrinsic part of the discourse and activities of health care services. In healthcare organizations, clinical and biomedical engineering departments play an essential role in maintaining the safety and efficiency of such equipment. One of the most challenging topics when it comes to such sophisticated equipment is the lifespan of medical equipment, where many factors will impact such characteristics of medical equipment through its life cycle. So far, many attempts have been made in order to address this issue where most of the approaches are kind of arbitrary approaches and one of the criticisms of existing approaches trying to estimate and understand the lifetime of a medical equipment lies under the inquiry of what are the environmental factors that can play into such a critical characteristic of a medical equipment. In an attempt to address this shortcoming, the purpose of our study rises where in addition to the standard technical factors taken into consideration through the decision-making process by a clinical engineer in case of medical equipment failure, the dimension of environmental factors shall be added. The investigations, researches and studies applied for the purpose of supporting the decision making process by a clinical engineers and assessing the lifespan of healthcare equipment’s in the Lebanese society was highly dependent on the identification of technical criteria’s that impacts the lifespan of a medical equipment where the affecting environmental factors didn’t receive the proper attention. The objective of our study is based on the need for introducing a new well-designed plan for evaluating medical equipment depending on two dimensions. According to this approach, the equipment that should be replaced or repaired will be classified based on a systematic method taking into account two essential criteria; the standard identified technical criteria and the added environmental criteria.

Keywords: technical, environmental, healthcare, characteristic of medical equipment

Procedia PDF Downloads 155
53 Development of PPy-M Composites Materials for Sensor Application

Authors: Yatimah Alias, Tilagam Marimuthu, M. R. Mahmoudian, Sharifah Mohamad

Abstract:

The rapid growth of science and technology in energy and environmental fields has enlightened the substantial importance of the conducting polymer and metal composite materials engineered at nano-scale. In this study, polypyrrole-cobalt composites (PPy-Co Cs) and polypyrrole-nickel oxide composites (PPy-NiO Cs) were prepared by a simple and facile chemical polymerization method with an aqueous solution of pyrrole monomer in the presence of metal salt. These composites then fabricated into non-enzymatic hydrogen peroxide (H2O2) and glucose sensor. The morphology and composition of the composites are characterized by the Field Emission Scanning Electron Microscope, Fourier Transform Infrared Spectrum and X-ray Powder Diffraction. The obtained results were compared with the pure PPy and metal oxide particles. The structural and morphology properties of synthesized composites are different from those of pure PPy and metal oxide particles, which were attributed to the strong interaction between the PPy and the metal particles. Besides, a favorable micro-environment for the electrochemical oxidation of H2O2 and glucose was achieved on the modified glassy carbon electrode (GCE) coated with PPy-Co Cs and PPy-NiO Cs respectively, resulting in an enhanced amperometric response. Both PPy-Co/GCE and PPy-NiO/GCE give high response towards target analyte at optimum condition of 500 μl pyrrole monomer content. Furthermore, the presence of pyrrole monomer greatly increases the sensitivity of the respective modified electrode. The PPy-Co/GCE could detect H2O2 in a linear range of 20 μM to 80 mM with two linear segments (low and high concentration of H2O2) and the detection limit for both ranges is 2.05 μM and 19.64 μM, respectively. Besides, PPy-NiO/GCE exhibited good electrocatalytic behavior towards glucose oxidation in alkaline medium and could detect glucose in linear ranges of 0.01 mM to 0.50 mM and 1 mM to 20 mM with detection limit of 0.33 and 5.77 μM, respectively. The ease of modifying and the long-term stability of this sensor have made it superior to enzymatic sensors, which must kept in a critical environment.

Keywords: metal oxide, composite, non-enzymatic sensor, polypyrrole

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52 Seroprevalence of Toxoplasmosis among Hemato-Oncology Patients in Tertiary Hospital of East Cost Malaysia

Authors: Aisha Khodijah Kholib Jati, Suharni Mohamad, Azlan Husin, Wan Suriana Wan Ab Rahman

Abstract:

Introduction: Toxoplasmosis is caused by an obligate intracellular parasite, Toxoplasma gondii (T. gondii). It is commonly asymptomatic in normal individual, but it can be fatal to immunocompromised patients as it can lead to severe complications such as encephalitis, chorioetinitis and myocarditis. Objective: The aim of the study was to determine the seroprevalence of toxoplasmosis and its association with socio-demographic and behavioral characteristics among hemato-oncology patients in Hospital USM. Methods: In this cross-sectional study, 56 hemato-oncology patients were screened for immunoglobulin M (IgM) antibodies, immunoglobulin G (IgG) antibodies, and IgG avidity of T. gondii by using ELISA Kit (BioRad, USA). For anti-T. gondii IgG antibody, titer ≥ 9 IU/ml was considered as recent infection, while for IgM, ratio ≥ 1.00 was considered as reactive for the anti-T. gondii IgM antibodies. Low avidity index is considered as recent infection within 20 weeks while high avidity considered as past infection. T. gondii exposure, socio-demographic and behavioral characteristics was assessed by a questionnaire and interview. Results: A total of 28 (50.0%) hemato-oncology patients were seropositive for T. gondii antibodies. Out of that total, 27 (48.21%) patients were IgG+/IgM- and one patient (1.79%) was IgG+/IgM+ with high avidity index. Univariate analysis showed that age, gender, ethnicity, marital status, educational level, employment status, stem cell transplant, blood transfusion, close contact with cats, water supply, and consumption of undercooked meat were not significantly associated with Toxoplasma seropositivity rate. Discussion: The seropositivity rate of IgG anti-T. gondii was high among hemato-oncology patients in Hospital USM. With impaired immune system, these patients might have a severe consequence if the infection reactivated. Therefore, screening for anti-T. gondii may be considered in the future. Moreover, health programme towards healthy food and good hygiene practice need to be implemented.

Keywords: immunocompromised, seroprevalence, socio-demographic, toxoplasmosis

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51 ELISA Based hTSH Assessment Using Two Sensitive and Specific Anti-hTSH Polyclonal Antibodies

Authors: Maysam Mard-Soltani, Mohamad Javad Rasaee, Saeed Khalili, Abdol Karim Sheikhi, Mehdi Hedayati

Abstract:

Production of specific antibody responses against hTSH is a cumbersome process due to the high identity between the hTSH and the other members of the glycoprotein hormone family (FSH, LH and HCG) and the high identity between the human hTSH and host animals for antibody production. Therefore, two polyclonal antibodies were purified against two recombinant proteins. Four possible ELISA tests were designed based on these antibodies. These ELISA tests were checked against hTSH and other glycoprotein hormones, and their sensitivity and specificity were assessed. Bioinformatics tools were used to analyze the immunological properties. After the immunogen region selection from hTSH protein, c terminal of B hTSH was selected and applied. Two recombinant genes, with these cut pieces (first: two repeats of C terminal of B hTSH, second: tetanous toxin+B hTSH C terminal), were designed and sub-cloned into the pET32a expression vector. Standard methods were used for protein expression, purification, and verification. Thereafter, immunizations of the white New Zealand rabbits were performed and the serums of them were used for antibody titration, purification and characterization. Then, four ELISA tests based on two antibodies were employed to assess the hTSH and other glycoprotein hormones. The results of these assessments were compared with standard amounts. The obtained results indicated that the desired antigens were successfully designed, sub-cloned, expressed, confirmed and used for in vivo immunization. The raised antibodies were capable of specific and sensitive hTSH detection, while the cross reactivity with the other members of the glycoprotein hormone family was minimum. Among the four designed tests, the test in which the antibody against first protein was used as capture antibody, and the antibody against second protein was used as detector antibody did not show any hook effect up to 50 miu/l. Both proteins have the ability to induce highly sensitive and specific antibody responses against the hTSH. One of the antibody combinations of these antibodies has the highest sensitivity and specificity in hTSH detection.

Keywords: hTSH, bioinformatics, protein expression, cross reactivity

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