Search results for: radial velocity difference
Commenced in January 2007
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Paper Count: 6422

Search results for: radial velocity difference

1202 Semantic Processing in Chinese: Category Effects, Task Effects and Age Effects

Authors: Yi-Hsiu Lai

Abstract:

The present study aimed to elucidate the nature of semantic processing in Chinese. Language and cognition related to the issue of aging are examined from the perspective of picture naming and category fluency tasks. Twenty Chinese-speaking adults (ranging from 25 to 45 years old) and twenty Chinese-speaking seniors (ranging from 65 to 75 years old) in Taiwan participated in this study. Each of them individually completed two tasks: a picture naming task and a category fluency task. Instruments for the naming task were sixty black-and-white pictures: thirty-five object and twenty-five action pictures. Category fluency task also consisted of two semantic categories – objects (or nouns) and actions (or verbs). Participants were asked to report as many items within a category as possible in one minute. Scores of action fluency and of object fluency were a summation of correct responses in these two categories. Category effects (actions vs. objects) and age effects were examined in these tasks. Objects were further divided into two major types: living objects and non-living objects. Actions were also categorized into two major types: action verbs and process verbs. Reaction time to each picture/question was additionally calculated and analyzed. Results of the category fluency task indicated that the content of information in Chinese seniors was comparatively deteriorated, thus producing smaller number of semantic-lexical items. Significant group difference was also found in the results of reaction time. Category Effect was significant for both Chinese adults and seniors in the semantic fluency task. Findings in the present study helped characterize the nature of semantic processing in Chinese-speaking adults and seniors and contributed to the issue of language and aging.

Keywords: semantic processing, aging, Chinese, category effects

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1201 Cholesterol Modulating Properties of a Proprietary Extract from Phyllanthus spp on Hypercholesteraemic Mice Models

Authors: Anne R. Fernandez, Mohammad Akmal Adnan, Tanes Prasat, Indu Bala Jaganath, Brian Kirby, Kamalan Jeevaratnam

Abstract:

Introduction: Plants from the Phyllantus genus have been used indigenously for the treatment of a variety of ailments for generations. A cocktail of phytonutrients prepared from a plant of the genus Phyllanthus has demonstrated the potential to alleviate ailments which include cardiovascular disorders. In this study, we investigated the cholesterol modulating properties of a highly purified proprietary extract of a Phyllanthus species in hypercholesteraemic mice. Methods: Hypercholesteraemia was induced in ICR mice by ad-libitum feeding of high fat diet daily for six weeks. The mice were then divided into 3 groups and force fed with 10mg/kg of atorvastatin, 200mg/kg of the proprietary Phyllanthus extract and water respectively. Blood samples were taken at the end of fourth week of treatment by a tail prick. At the end of the eighth week of treatment, mice were sacrificed and serum levels of total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triglycerides were measured. Results: The mean cholesterol levels in the mice fed with high fat diet were 44% (p < 0.05) higher than the mice on normal diet thus validating the model developed. The plasma HDL was significantly elevated in mice treated with the formulation (p ˂ 0.05) in comparison to the statin-treated and control mice. The total cholesterol levels in the mice treated with the proprietary extract were reduced significantly (p < 0.05) at the end of 4 weeks of treatment in comparison to the mice treated with atorvastatin. By the end of 8 weeks of treatment, there was no significant difference in the cholesterol levels of the mice in all groups. Conclusion: These results demonstrate that this proprietary extract from Phyllanthus species has the beneficial effect of reducing total cholesterol level more rapidly than atorvastatin and increasing HDL levels. Since an increase in the HDL cholesterol can reduce the risk of heart disease, this proprietary extract is a useful and safe therapeutic option compared to atorvastatin.

Keywords: high-density lipoprotein, hypercholesteraemic mice model, ICR mice, Phyllanthus spp.

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1200 Vertebrate Model to Examine the Biological Effectiveness of Different Radiation Qualities

Authors: Rita Emília Szabó, Róbert Polanek, Tünde Tőkés, Zoltán Szabó, Szabolcs Czifrus, Katalin Hideghéty

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Purpose: Several feature of zebrafish are making them amenable for investigation on therapeutic approaches such as ionizing radiation. The establishment of zebrafish model for comprehensive radiobiological research stands in the focus of our investigation, comparing the radiation effect curves of neutron and photon irradiation. Our final aim is to develop an appropriate vertebrate model in order to investigate the relative biological effectiveness of laser driven ionizing radiation. Methods and Materials: After careful dosimetry series of viable zebrafish embryos were exposed to a single fraction whole-body neutron-irradiation (1,25; 1,875; 2; 2,5 Gy) at the research reactor of the Technical University of Budapest and to conventional 6 MeV photon beam at 24 hour post-fertilization (hpf). The survival and morphologic abnormalities (pericardial edema, spine curvature) of each embryo were assessed for each experiment at 24-hour intervals from the point of fertilization up to 168 hpf (defining the dose lethal for 50% (LD50)). Results: In the zebrafish embryo model LD50 at 20 Gy dose level was defined and the same lethality were found at 2 Gy dose from the reactor neutron beam resulting RBE of 10. Dose-dependent organ perturbations were detected on macroscopic (shortening of the body length, spine curvature, microcephaly, micro-ophthalmia, micrognathia, pericardial edema, and inhibition of yolk sac resorption) and microscopic (marked cellular changes in skin, cardiac, gastrointestinal system) with the same magnitude of dose difference. Conclusion: In our observations, we found that zebrafish embryo model can be used for investigating the effects of different type of ionizing radiation and this system proved to be highly efficient vertebrate model for preclinical examinations.

Keywords: ionizing radiation, LD50, relative biological effectiveness, zebrafish embryo

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1199 Ethyl Methane Sulfonate-Induced Dunaliella salina KU11 Mutants Affected for Growth Rate, Cell Accumulation and Biomass

Authors: Vongsathorn Ngampuak, Yutachai Chookaew, Wipawee Dejtisakdi

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Dunaliella salina has great potential as a system for generating commercially valuable products, including beta-carotene, pharmaceuticals, and biofuels. Our goal is to improve this potential by enhancing growth rate and other properties of D. salina under optimal growth conditions. We used ethyl methane sulfonate (EMS) to generate random mutants in D. salina KU11, a strain classified in Thailand. In a preliminary experiment, we first treated D. salina cells with 0%, 0.8%, 1.0%, 1.2%, 1.44% and 1.66% EMS to generate a killing curve. After that, we randomly picked 30 candidates from approximately 300 isolated survivor colonies from the 1.44% EMS treatment (which permitted 30% survival) as an initial test of the mutant screen. Among the 30 survivor lines, we found that 2 strains (mutant #17 and #24) had significantly improved growth rates and cell number accumulation at stationary phase approximately up to 1.8 and 1.45 fold, respectively, 2 strains (mutant #6 and #23) had significantly decreased growth rates and cell number accumulation at stationary phase approximately down to 1.4 and 1.35 fold, respectively, while 26 of 30 lines had similar growth rates compared with the wild type control. We also analyzed cell size for each strain and found there was no significant difference comparing all mutants with the wild type. In addition, mutant #24 had shown an increase of biomass accumulation approximately 1.65 fold compared with the wild type strain on day 5 that was entering early stationary phase. From these preliminary results, it could be feasible to identify D. salina mutants with significant improved growth rate, cell accumulation and biomass production compared to the wild type for the further study; this makes it possible to improve this microorganism as a platform for biotechnology application.

Keywords: Dunaliella salina, ethyl methyl sulfonate, growth rate, biomass

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1198 Comparison of Deep Brain Stimulation Targets in Parkinson's Disease: A Systematic Review

Authors: Hushyar Azari

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Aim and background: Deep brain stimulation (DBS) is regarded as an important therapeutic choice for Parkinson's disease (PD). The two most common targets for DBS are the subthalamic nucleus (STN) and globus pallidus (GPi). This review was conducted to compare the clinical effectiveness of these two targets. Methods: A systematic literature search in electronic databases: Embase, Cochrane Library and PubMed were restricted to English language publications 2010 to 2021. Specified MeSH terms were searched in all databases. Studies which evaluated the Unified Parkinson's Disease Rating Scale (UPDRS) III were selected by meeting the following criteria: (1) compared both GPi and STN DBS; (2) had at least three months follow-up period; (3)at least five participants in each group; (4)conducted after 2010. Study quality assessment was performed using the Modified Jadad Scale. Results: 3577 potentially relevant articles were identified, of these, 3569 were excluded based on title and abstract, duplicate and unsuitable article removal. Eight articles satisfied the inclusion criteria and were scrutinized (458 PD patients). According to Modified Jadad Scale, the majority of included studies had low evidence quality which was a limitation of this review. 5 studies reported no statistically significant between-group difference for improvements in UPDRS ш scores. At the same time, there were some results in terms of pain, action tremor, rigidity, and urinary symptoms, which indicated that STN DBS might be a better choice. Regarding the adverse effects, GPi was superior. Conclusion: It is clear that other larger randomized clinical trials with longer follow-up periods and control groups are needed to decide which target is more efficient for deep brain stimulation in Parkinson’s disease and imposes fewer adverse effects on the patients. Meanwhile, STN seems more reasonable according to the results of this systematic review.

Keywords: brain stimulation, globus pallidus, Parkinson's disease, subthalamic nucleus

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1197 Resistances among Sexual Offenders on Specific Stage of Change

Authors: Chang Li Yu

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Resistances commonly happened during sexual offenders treatment program (SOTP), and removing resistances was one of the treatment goals on it. Studies concerning treatment effectiveness relied on pre- and post-treatment evaluations, however, no significant difference on resistance revealed after treatment, and the above consequences generally contributed to the low motivation for change instead. Therefore, the aim of this study was to investigate the resistance across each stage of change among sexual offenders (SO). The present study recruited prisoned SO in Taiwan, excluding those with literacy difficulties; finally, 272 participants were included. Of all participants completed revised version of URICA (University of Rhode Island Change Assessment) and resistance scale specifically for SO. The former included four stages of change: pre-contemplation (PC), contemplation (C), action (A), and maintain (M); the later composed eight types of resistance: system blaming, victims blaming, problems with treatment alliance, social justification, hopelessness, isolation, psychological reactance, and passive reactance. Both of the instruments were with well reliability and validity. Descriptive statistics and ANOVA were performed. All of 272 participants, age under 25 were 18(6.6%), 25-39 were 133(48.9%), 40-54 were 102(37.5%), and age over 55 were 19(7.0%); college level and above were 53(19.5%), high school level were 110(40.4%), and under high school level were 109(40.1%); first offended were 117(43.0%), and recidivist were 23(8.5%). Further deleting data with missing values and invalid questionnaires, SO with stage of change on PC were 43(18.9%), C were 109(47.8%), A were 70(30.7%), and on M were 6(2.6%). One-way ANOVA showed significant differences on every kind of resistances, excepting isolation and passive reactance. Post-hoc analysis showed that SO with different stages had their main resistance. There are two contributions to the present study. First, this study provided a clinical and theoretical measurement of evaluation that was never used in the past. Second, this study used an evidence-based methodology to prove a clinical perspective differed from the past, suggesting that resistances to treatment on SO appear the whole therapeutic process, when SO progress into the next stage of change, clinicians have to deal with their main resistance for working through the therapy.

Keywords: resistance, sexual offenders treatment program (SOTP), motivation for change, prisoned sexual offender

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1196 Assessing the Benefits of Super Depo Sutorejo as a Model of integration of Waste Pickers in a Sustainable City Waste Management

Authors: Yohanes Kambaru Windi, Loetfia Dwi Rahariyani, Dyah Wijayanti, Eko Rustamaji

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Surabaya, the second largest city in Indonesia, has been struggling for years with waste production and its management. Nearly 11,000 tons of waste are generated daily by domestic, commercial and industrial areas. It is predicted that approximately 1,300 tons of waste overflew the Benowo Landfill daily in 2013 and projected that the landfill operation will be critical in 2015. The Super Depo Sutorejo (SDS) is a pilot project on waste management launched by the government of Surabaya in March 2013. The project is aimed to reduce the amount of waste dumped in landfill by sorting the recyclable and organic waste for composting by employing waste pickers to sort the waste before transported to landfill. This study is intended to assess the capacity of SDS to process and reduce waste and its complementary benefits. It also overviews the benefits of the project to the waste pickers in term of satisfaction to the job. Waste processing data-sheets were used to assess the difference between input and outputs waste. A survey was distributed to 30 waste pickers and interviews were conducted as a further insight on a particular issue. The analysis showed that SDS enable to reduce waste up to 50% before dumped in the final disposal area. The cost-benefits analysis using cost differential calculation revealed the economic benefit is considerable low, but composting may substitute tangible benefits for maintain the city’s parks. Waste pickers are mostly satisfied with their job (i.e. Salary, health coverage, job security), services and facilities available in SDS and enjoyed rewarding social life within the project. It is concluded that SDS is an effective and efficient model for sustainable waste management and reliable to be developed in developing countries. It is a strategic approach to empower and open up working opportunity for the poor urban community and prolong the operation of landfills.

Keywords: cost-benefits, integration, satisfaction, waste management

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1195 Odor-Color Association Stroop-Task and the Importance of an Odorant in an Odor-Imagery Task

Authors: Jonathan Ham, Christopher Koch

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There are consistently observed associations between certain odors and colors, and there is an association between the ability to imagine vivid visual objects and imagine vivid odors. However, little has been done to investigate how the associations between odors and visual information effect visual processes. This study seeks to understand the relationship between odor imaging, color associations, and visual attention by utilizing a Stroop-task based on common odor-color associations. This Stroop-task was designed using three fruits with distinct odors that are associated with the color of the fruit: lime with green, strawberry with red, and lemon with yellow. Each possible word-color combination was presented in the experimental trials. When the word matched the associated color (lime written in green) it was considered congruent; if it did not, it was considered incongruent (lime written in red or yellow). In experiment I (n = 34) participants were asked to both imagine the odor of the fruit on the screen and identify which fruit it was, and each word-color combination was presented 20 times (a total of 180 trials, with 60 congruent and 120 incongruent instances). Response time and error rate of the participant responses were recorded. There was no significant difference in either measure between the congruent and incongruent trials. In experiment II participants (n = 18) followed the identical procedure as in the previous experiment with the addition of an odorant in the room. The odorant (orange) was not the fruit or color used in the experimental trials. With a fruit-based odorant in the room, the response times (measured in milliseconds) between congruent and incongruent trials were significantly different, with incongruent trials (M = 755.919, SD = 239.854) having significantly longer response times than congruent trials (M = 690.626, SD = 198.822), t (1, 17) = 4.154, p < 0.01. This suggests that odor imagery does affect visual attention to colors, and the ability to inhibit odor-color associations; however, odor imagery is difficult and appears to be facilitated in the presence of a related odorant.

Keywords: odor-color associations, odor imagery, visual attention, inhibition

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1194 Comparing the Efficacy of Minimally Supervised Home-Based and Closely Supervised Gym Based Exercise Programs on Weight Reduction and Insulin Resistance after Bariatric Surgery

Authors: Haleh Dadgostar, Sara Kaviani, Hanieh Adib, Ali Mazaherinezhad, Masoud Solaymani-Dodaran, Fahimeh Soheilipour, Abdolreza Pazouki

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Background and Objectives: Effectiveness of various exercise protocols in weight reduction after bariatric surgery has not been sufficiently explored in the literature. We compared the effect of minimally supervised home-based and closely supervised Gym based exercise programs on weight reduction and insulin resistance after bariatric surgery. Methods: Women undergoing gastric bypass surgery were invited to participate in an exercise program and were randomly allocated into two groups. They were either offered a minimally supervised home-based (MSHB) or closely supervised Gym-based (CSGB) exercise program. The CSGB protocol constitute two sessions per week of training under ACSM guidelines. In the MSHB protocol participants received a notebook containing a list of recommended aerobic and resistance exercises, a log to record their activity and a schedule of follow up phone calls and clinic visits. Both groups received a pedometer. We measured their weight, BMI, lipid profile, FBS, and insulin level at the baseline and after 20 weeks of exercise and were compared at the end of the study. Results: A total of 80 patients completed our study (MSHB=38 and CSGB=42). The baseline comparison showed that the two groups are similar. Using the ANCOVA method of analysis the mean change in BMI (covariate: BMI at the beginning of the study) was slightly better in CSGB compared with the MSHB (between-group mean difference: 3.33 (95%CI 4.718 to 1.943, F: 22.844 p < 0.001)). Conclusion: Our results showed that both MSHB and CSGB exercise methods are somewhat equally effective in improvement of studied factors in the two groups. With considerably lower costs of Minimally Supervised Home Based exercise programs, these methods should be considered when adequate funding are not available.

Keywords: postoperative exercise, insulin resistance, bariatric surgery, morbid obesity

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1193 Nanoscale Mapping of the Mechanical Modifications Occurring in the Brain Tumour Microenvironment by Atomic Force Microscopy: The Case of the Highly Aggressive Glioblastoma and the Slowly Growing Meningioma

Authors: Gabriele Ciasca, Tanya E. Sassun, Eleonora Minelli, Manila Antonelli, Massimiliano Papi, Antonio Santoro, Felice Giangaspero, Roberto Delfini, Marco De Spirito

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Glioblastoma multiforme (GBM) is an extremely aggressive brain tumor, characterized by a diffuse infiltration of neoplastic cells into the brain parenchyma. Although rarely considered, mechanical cues play a key role in the infiltration process that is extensively mediated by the tumor microenvironment stiffness and, more in general, by the occurrence of aberrant interactions between neoplastic cells and the extracellular matrix (ECM). Here we provide a nano-mechanical characterization of the viscoelastic response of human GBM tissues by indentation-type atomic force microscopy. High-resolution elasticity maps show a large difference between the biomechanics of GBM tissues and the healthy peritumoral regions, opening possibilities to optimize the tumor resection area. Moreover, we unveil the nanomechanical signature of necrotic regions and anomalous vasculature, that are two major hallmarks useful for glioma staging. Actually, the morphological grading of GBM relies mainly on histopathological findings that make extensive use of qualitative parameters. Our findings have the potential to positively impact on the development of novel quantitative methods to assess the tumor grade, which can be used in combination with conventional histopathological examinations. In order to provide a more in-depth description of the role of mechanical cues in tumor progression, we compared the nano-mechanical fingerprint of GBM tissues with that of grade-I (WHO) meningioma, a benign lesion characterized by a completely different growth pathway with the respect to GBM, that, in turn hints at a completely different role of the biomechanical interactions.

Keywords: AFM, nano-mechanics, nanomedicine, brain tumors, glioblastoma

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1192 Study and Fine Characterization of the SS 316L Microstructures Obtained by Laser Beam Melting Process

Authors: Sebastien Relave, Christophe Desrayaud, Aurelien Vilani, Alexey Sova

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Laser beam melting (LBM) is an additive manufacturing process that enables complex 3D parts to be designed. This process is now commonly employed for various applications such as chemistry or energy, requiring the use of stainless steel grades. LBM can offer comparable and sometimes superior mechanical properties to those of wrought materials. However, we observed an anisotropic microstructure which results from the process, caused by the very high thermal gradients along the building axis. This microstructure can be harmful depending on the application. For this reason, control and prediction of the microstructure are important to ensure the improvement and reproducibility of the mechanical properties. This study is focused on the 316L SS grade and aims at understanding the solidification and transformation mechanisms during process. Experiments to analyse the nucleation and growth of the microstructure obtained by the LBM process according to several conditions. These samples have been designed on different type of support bulk and lattice. Samples are produced on ProX DMP 200 LBM device. For the two conditions the analysis of microstructures, thanks to SEM and EBSD, revealed a single phase Austenite with preferential crystallite growth along the (100) plane. The microstructure was presented a hierarchical structure consisting columnar grains sizes in the range of 20-100 µm and sub grains structure of size 0.5 μm. These sub-grains were found in different shapes (columnar and cellular). This difference can be explained by a variation of the thermal gradient and cooling rate or element segregation while no sign of element segregation was found at the sub-grain boundaries. A high dislocation concentration was observed at sub-grain boundaries. These sub-grains are separated by very low misorientation walls ( < 2°) this causes a lattice of curvature inside large grain. A discussion is proposed on the occurrence of these microstructures formation, in regard of the LBM process conditions.

Keywords: selective laser melting, stainless steel, microstructure

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1191 Performance of Rural and Urban Adult Participants on Neuropsychological Tests in Zambia

Authors: Happy Zulu

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Neuropsychological examination is an important way of formally assessing brain function. While there is so much documentation about the influence that some factors, such as age and education, have on neuropsychological tests (NP), not so much has been done to assess the influence that residency (rural/urban) may have. The specific objectives of this study were to establish if there is a significant difference in mean test scores on NP tests between rural and urban participants and to assess which tests on the Zambia Neurobehavioural Test Battery (ZNTB) are more affected by the participants‘ residency (rural/urban) and to determine the extent to which education, gender, and age predict test performance on NP tests for rural and urban participants. The participants (324) were drawn from both urban and rural areas of Zambia (Rural = 152 and Urban = 172). However, only 234 participants (Rural = 152 and Urban 82) were used for all the analyses in this particular study. The 234 participants were used as the actual proportion of the rural vs urban population in Zambia was 65% : 35%, respectively (CSO, 2003). The rural-urban ratio for the participants that were captured during the data collection process was 152 : 172, respectively. Thus, all the rural participants (152) were included and 90 of the 172 urban participants were randomly excluded so that the rural/urban ratio reached the desired 65% : 35 % which was the required ideal statistic for appropriate representation of the actual population in Zambia. Data on NP tests were analyzed from 234 participants, rural (N=152) reflecting 65% and urban (N=82) reflecting 35%. T-tests indicated that urban participants had superior performances in all the seven NP test domains, and all the mean differences in all these domains were found to be statistically significant. Residency had a large or moderate effect in five domains, while its effect size was small only in two of the domains. A standard multiple regression revealed that education, age and residency as predictor variables made a significant contribution to variance in performance on various domains of the ZNTB. However, the gender of participants was not a major factor in determining one‘s performance on neuropsychological tests. This particular report is part of an ongoing, larger, cutting-edge study aimed at formulating the normative data for Zambia with regard to performance on neuropsychological tests. This is necessary for appropriate, effective, and efficient assessment or diagnosis of various neurocognitive and neurobehavioural deficits that a number of people may currently be suffering from. It has been shown in this study that it is vital to make careful analyses of the variables that may be associated with one‘s performance on neuropsychological tests.

Keywords: neuropsychology, neurobehavioural, residency, Zambia

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1190 The Role of Financial and Non-Financial Institutions in Promoting Entrepreneurship in Micro small and Medium Enterprises

Authors: Lemuel David

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The importance of the Micro, Small, and Medium Enterprises sector is well recognized for its legitimate contribution to the Macroeconomic objectives of the Republic of Liberia, like generation of employment, input t, exports, and enhancing entrepreneurship. Right now, Medium and Small enterprises accounts for about 99 percent of the industrial units in the country, contributing 60 percent of the manufacturing sector output and approximately one-third of the nation’s exports. The role of various financial institutions like ECO bank and Non-financial Institutions like Bearch Limited support promoting the growth of Micro, Small, and Medium Enterprises is unique. A small enterprise or entrepreneur gets many types of assistance from different institutions for varied purposes in the course of his entrepreneurial journey. This paper focuses on the factors related to financial institutional support and non-financial institutional support entrepreneurs to the growth of Medium and Small enterprises in the Republic of Liberia. The significance of this paper is to support Policy and Institutional Support for Medium and Small enterprises to know the views of entrepreneurs about financial and non-financial support systems in the Republic of Liberia. This study was carried out through a survey method, with the use of questionnaires. The population for this study consisted of all registered Medium and Small enterprises which have been registered during the years 2004-2014 in the republic of Liberia. The sampling method employed for this study was a simple random technique and determined a sample size of 400. Data for the study was collected using a standard questionnaire. The questionnaire consisted of two parts: the first part consisted of questions on the profile of the respondents. The second part covers (1) financial, promotional factors and (2) non-financial promotional factors. The results of the study are based on financial and non-financial supporting activities provided by institutions to Medium and Small enterprises. After investigation, it has been found that there is no difference in the support given by Financial Institutions and non-financial Institutions. Entrepreneurs perceived “collateral-free schemes and physical infrastructure support factors are highest contributing to entry and growth of Medium and Small enterprises.

Keywords: micro, small, and medium enterprises financial institutions, entrepreneurship

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1189 Effects of a 6-Month Caloric Restriction Induced-Weight Loss Program in Obese Postmenopausal Women with and without the Metabolic Syndrome: A MONET Study

Authors: Ahmed Ghachem, Denis Prud’homme, Rémi-Rabasa-Lhoret, M. Brochu

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Objective: To compare the effects of a CR on body composition, lipid profile and glucose homeostasis in obese postmenopausal women with and without MetS. Methods: Secondary analyses were performed on seventy-three inactive obese postmenopausal women (age: 57.7 ± 4.8 yrs; body mass index: 32.4 ± 4.6 kg/m2) who participated in the 6-month caloric restriction arm of a study of the Montreal-Ottawa New Emerging Team. The harmonized MetS definition was used to categorized participants with MetS [n = 20, 27.39%] and without MetS [n = 53, 72.61%]. Variables of interest were: body composition (DXA), body fat distribution (CT scan), glucose homeostasis at the fasting state and during a euglycemic/hyperinsulinemic clamp, fasting lipids and resting blood pressure. Results: By design, the MetS group had a worse cardiometabolic profile; while both groups were comparable for age. Fifty-five patients out of seventy-three displayed no change in MetS status after the intervention. Twelve participants out of twenty (or 60.0%) in the MetS group had no more MetS after weight loss (P= NS); while six participants out of fifty three (or 11.3%) in the other group developed the MetS after the intervention (P= NS). Overall, indices of body composition and body fat distribution improved significantly and similarly in both groups (P between 0.03 and 0.0001). Furthermore, with the exception of triglyceride levels and triglycerides/HDL-C ratio, which decrease significantly more in the MetS group (P ≤ 0.05), no difference was observed between groups for the other variables of the cardiometabolic profile. Conclusion: Despite no overall significant effects on MetS, heterogeneous results were obtained in response to weight loss in the present study; with some improving the MetS while other displaying deteriorations. Further studies are needed in order to identify factors and phenotypes associated with positive and negative cardiometabolic responses to CR intervention.

Keywords: menopause, obesity, physical inactivity, metabolic syndrome, caloric restriction, weight loss

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1188 Infant Care Practice in Hadiya Culture: Case Study of Harche Auyaya

Authors: Dawit Thomas

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Feeding and weaning practices vary from culture to culture and depend on different child-rearing values. The socio-cultural dimensions that influence the acceptable infant feeding practices are varied and complex. Understanding cultural differences in beliefs and practices relating to infant feeding is important to enhance designing programs for delivering successful psychological, social, physiological and economic well-being of mothers and infants. The main purpose of this study was exploring mothers infant feeding practices in the context of Hadiyya culture. After purposively selecting Harche Huyaya Uyaya Kebele eight infant feeding mothers were selected using snowball sampling technique. The study employed interviews and focus group discussion. The study found out early initiation and prolonged breastfeeding and early complementary feeding in some instances immediately after birth. In addition, infants were not forced to wean unless the mothers encounter pressing issues like pregnancy and health related problems. Furthermore, the main weaning techniques were putting unpleasant materials on the tip of nipples and sending infants to grandparents home. The study also found out gender difference in weaning, i.e., early initiation of weaning for girls. This can be indicative of gender-based bias on weaning practice. Finally, health extension workers, office of women and children affairs and Hadiyya Zone Tourism office should organize awareness raising programs to preserve vital infant feeding practices like prolonged breastfeeding and length of weaning. In addition, the offices should raise awareness among communities on negative side effects of sending infant to grandparents home that may weaken infant-mothers attachment and create favorable ground for the development of phobia.

Keywords: feeding, infant, practices, weaning

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1187 Improved Benzene Selctivity for Methane Dehydroaromatization via Modifying the Zeolitic Pores by Dual Templating Approach

Authors: Deepti Mishra, K. K Pant, Xiu Song Zhao, Muxina Konarova

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Catalytic transformation of simplest hydrocarbon methane into benzene and valuable chemicals over Mo/HZSM-5 has a great economic potential, however, it suffers serious hurdles due to the blockage in the micropores because of extensive coking at high temperature during methane dehydroaromatization (MDA). Under such conditions, it necessitates the design of micro/mesoporous ZSM-5, which has the advantages viz. uniform dispersibility of MoOx species, consequently the formation of active Mo sites in the micro/mesoporous channel and lower carbon deposition because of improved mass transfer rate within the hierarchical pores. In this study, we report a unique strategy to control the porous structures of ZSM-5 through a dual templating approach, utilizing C6 and C12 -surfactants as porogen. DFT studies were carried out to correlate the ZSM-5 framework development using the C6 and C12 surfactants with structure directing agent. The structural and morphological parameters of the synthesized ZSM-5 were explored in detail to determine the crystallinity, porosity, Si/Al ratio, particle shape, size, and acidic strength, which were further correlated with the physicochemical and catalytic properties of Mo modified HZSM-5 catalysts. After Mo incorporation, all the catalysts were tested for MDA reaction. From the activity test, it was observed that C6 surfactant-modified hierarchically porous Mo/HZSM-5(H) showed the highest benzene formation rate (1.5 μmol/gcat. s) and longer catalytic stability up to 270 min of reaction as compared to the conventional microporous Mo/HZSM-5(C). In contrary, C12 surfactant modified Mo/HZSM-5(D) is inferior towards MDA reaction (benzene formation rate: 0.5 μmol/gcat. s). We ascribed that the difference in MDA activity could be due to the hierarchically interconnected meso/microporous feature of Mo/HZSM-5(H) that precludes secondary reaction of coking from benzene and hence contributing substantial stability towards MDA reaction.

Keywords: hierarchical pores, Mo/HZSM-5, methane dehydroaromatization, coke deposition

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1186 Oblique Radiative Solar Nano-Polymer Gel Coating Heat Transfer and Slip Flow: Manufacturing Simulation

Authors: Anwar Beg, Sireetorn Kuharat, Rashid Mehmood, Rabil Tabassum, Meisam Babaie

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Nano-polymeric solar paints and sol-gels have emerged as a major new development in solar cell/collector coatings offering significant improvements in durability, anti-corrosion and thermal efficiency. They also exhibit substantial viscosity variation with temperature which can be exploited in solar collector designs. Modern manufacturing processes for such nano-rheological materials frequently employ stagnation flow dynamics under high temperature which invokes radiative heat transfer. Motivated by elaborating in further detail the nanoscale heat, mass and momentum characteristics of such sol gels, the present article presents a mathematical and computational study of the steady, two-dimensional, non-aligned thermo-fluid boundary layer transport of copper metal-doped water-based nano-polymeric sol gels under radiative heat flux. To simulate real nano-polymer boundary interface dynamics, thermal slip is analysed at the wall. A temperature-dependent viscosity is also considered. The Tiwari-Das nanofluid model is deployed which features a volume fraction for the nanoparticle concentration. This approach also features a Maxwell-Garnet model for the nanofluid thermal conductivity. The conservation equations for mass, normal and tangential momentum and energy (heat) are normalized via appropriate transformations to generate a multi-degree, ordinary differential, non-linear, coupled boundary value problem. Numerical solutions are obtained via the stable, efficient Runge-Kutta-Fehlberg scheme with shooting quadrature in MATLAB symbolic software. Validation of solutions is achieved with a Variational Iterative Method (VIM) utilizing Langrangian multipliers. The impact of key emerging dimensionless parameters i.e. obliqueness parameter, radiation-conduction Rosseland number (Rd), thermal slip parameter (α), viscosity parameter (m), nanoparticles volume fraction (ϕ) on non-dimensional normal and tangential velocity components, temperature, wall shear stress, local heat flux and streamline distributions is visualized graphically. Shear stress and temperature are boosted with increasing radiative effect whereas local heat flux is reduced. Increasing wall thermal slip parameter depletes temperatures. With greater volume fraction of copper nanoparticles temperature and thermal boundary layer thickness is elevated. Streamlines are found to be skewed markedly towards the left with positive obliqueness parameter.

Keywords: non-orthogonal stagnation-point heat transfer, solar nano-polymer coating, MATLAB numerical quadrature, Variational Iterative Method (VIM)

Procedia PDF Downloads 135
1185 Treatment of a Galvanization Wastewater in a Fixed-Bed Column Using L. hyperborean and P. canaliculata Macroalgae as Natural Cation Exchangers

Authors: Tatiana A. Pozdniakova, Maria A. P. Cechinel, Luciana P. Mazur, Rui A. R. Boaventura, Vitor J. P. Vilar.

Abstract:

Two brown macroalgae, Laminaria hyperborea and Pelvetia canaliculata, were employed as natural cation exchangers in a fixed-bed column for Zn(II) removal from a galvanization wastewater. The column (4.8 cm internal diameter) was packed with 30-59 g of previously hydrated algae up to a bed height of 17-27 cm. The wastewater or eluent was percolated using a peristaltic pump at a flow rate of 10 mL/min. The effluent used in each experiment presented similar characteristics: pH of 6.7, 55 mg/L of chemical oxygen demand and about 300, 44, 186 and 244 mg/L of sodium, calcium, chloride and sulphate ions, respectively. The main difference was nitrate concentration: 20 mg/L for the effluent used with L. hyperborean and 341 mg/L for the effluent used with P. canaliculata. The inlet zinc concentration also differed slightly: 11.2 mg/L for L. hyperborean and 8.9 mg/L for P. canaliculata experiments. The breakthrough time was approximately 22.5 hours for both macroalgae, corresponding to a service capacity of 43 bed volumes. This indicates that 30 g of biomass is able to treat 13.5 L of the galvanization wastewater. The uptake capacities at the saturation point were similar to that obtained in batch studies (unpublished data) for both algae. After column exhaustion, desorption with 0.1 M HNO3 was performed. Desorption using 9 and 8 bed volumes of eluent achieved an efficiency of 100 and 91%, respectively for L. hyperborean and P. canaliculata. After elution with nitric acid, the column was regenerated using different strategies: i) convert all the binding sites in the sodium form, by passing a solution of 0.5 M NaCl, until achieve a final pH of 6.0; ii) passing only tap water in order to increase the solution pH inside the column until pH 3.0, and in this case the second sorption cycle was performed using protonated algae. In the first approach, in order to remove the excess of salt inside the column, distilled water was passed through the column, leading to the algae structure destruction and the column collapsed. Using the second approach, the algae remained intact during three consecutive sorption/desorption cycles without loss of performance.

Keywords: biosorption, zinc, galvanization wastewater, packed-bed column

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1184 A Case Study of Rainfall Derived Inflow/Infiltration in a Separate Sewer System in Gwangju, Korea

Authors: Bumjo Kim, Hyun Jin Kim, Joon Ha Kim

Abstract:

The separate sewer system is that collects the wastewater as a sewer pipe and rainfall as a stormwater pipe separately, and then sewage is treated in the wastewater treatment plant, the stormwater is discharged to rivers or lakes through stormwater drainage pipes. Unfortunately, even for separate sewer systems, it is not possible to prevent Rainfall Driven Inflow/Infiltration(RDII) completely to the sewer pipe. Even if the sewerage line is renovated, there is an ineluctable RDII due to the combined sewer system in the house or the difficulty of sewage maintenance in private areas. The basic statistical analysis was performed using environmental data including rainfall, sewage, water qualities and groundwater level in the strict of Gwangju in ​South Korea. During rainfall in the target area, RDII showed an increased rate of 13.4 ~ 53.0% compared to that of a clear day and showed a rapid hydrograph response of 0.3 ~ 3.0 hr. As a result of water quality analysis, BOD5 concentration decreased by 17.3 % and salinity concentration decreased by 8.8 % at the representative spot in the project area compared to the sunny day during rainfall. In contrast to the seasonal fluctuation range of 0.38 m ~ 0.55 m in groundwater in Gwangju area and 0.58 m ~ 0.78 m in monthly fluctuation range, while the difference between groundwater level and the depth of sewer pipe laying was 2.70 m on average, which is larger than the range of fluctuation. Comprehensively, it can be concluded that the increasing of flowrate at sewer line is due to not infiltration water caused by groundwater level rise, construction failure, cracking due to joint failure or conduit deterioration, rainfall was directly inflowed into the sewer line rapidly. Acknowledgements: This work was supported by the 'Climate Technology Development and Application' research project (#K07731) through a grant provided by GIST in 2017.

Keywords: ground water, rainfall, rainfall driven inflow/infiltration, separate sewer system

Procedia PDF Downloads 159
1183 Paper Concrete: A Step towards Sustainability

Authors: Hemanth K. Balaga, Prakash Nanthagopalan

Abstract:

Every year a huge amount of paper gets discarded of which only a minute fraction is being recycled and the rest gets dumped as landfills. Paper fibres can be recycled only a limited number of times before they become too short or weak to make high quality recycled paper. This eventually adds to the already big figures of waste paper that is being generated and not recycled. It would be advantageous if this prodigious amount of waste can be utilized as a low-cost sustainable construction material and make it as a value added product. The generic term for the material under investigation is paper-concrete. This is a fibrous mix made of Portland cement, water and pulped paper and/or other aggregates. The advantages of this material include light weight, good heat and sound insulation capability and resistance to flame. The disadvantages include low strength compared to conventional concrete and its hydrophilic nature. The properties vary with the variation of cement and paper content in the mix. In the present study, Portland Pozzolona Cement and news print paper were used for the preparation of paper concrete cubes. Initially, investigations were performed to determine the minimum soaking period required for the softening of the paper fibres. Further different methodologies were explored for proper blending of the pulp with cement paste. The properties of paper concrete vary with the variation of cement to paper to water ratio. The study mainly addresses the parameters of strength and weight loss of the concrete cubes with age and the time that is required for the dry paper fibres to become soft enough in water to bond with the cement. The variation of compressive strength with cement content, water content, and time was studied. The water loss of the cubes with time and the minimum time required for the softening of paper fibres were investigated .Results indicate that the material loses 25-50 percent of the initial weight at the end of 28 days, and a maximum 28 day compressive strength (cubes) of 5.4 Mpa was obtained.

Keywords: soaking time, difference water, minimum water content, maximum water content

Procedia PDF Downloads 257
1182 Exercise Intensity Increasing Appetite, Energy, Intake Energy Expenditure, and Fat Oxidation in Sedentary Overweight Individuals

Authors: Ghalia Shamlan, M. Denise Robertson, Adam Collins

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Appetite control (i.e. control of energy intake) is important for weight maintenance. Exercise contributes to the most variable component of energy expenditure (EE) but its impact is beyond the energy cost of exercise including physiological, behavioural, and appetite effects. Exercise is known to acutely influence effect appetite but evidence as to the independent effect of intensity is lacking. This study investigated the role of exercise intensity on appetite, energy intake (EI), appetite related hormone, fat utilisation and subjective measures of appetite. One hour after a standardised breakfast, 10 sedentary overweight volunteers. Subjects undertook either 8 repeated 60 second bouts of cycling at 95% VO2max (high intensity) or 30 minutes of continuous cycling, at a fixed cadence, equivalent to 50% of the participant’s VO2max (low intensity) in a randomised crossover design. Glucose, NEFA, glucagon-like peptide-1 (GLP-1) were measured fasted, postprandial, and pre and post-exercise. Satiety was assessed subjectively throughout the study using visual analogue scales (VAS). Ad libitum intake of a pasta meal was measured at the end (3-h post-breakfast). Interestingly, there was not significant difference in EE fat oxidation between HI and LI post-exercise. Also, no significant effect of high intensity (HI) was observed on the ad libitum meal, 24h and 48h EI post-exercise. However the mean 24h EI was 3000 KJ lower following HI than low intensity (LI). Despite, no significant differences in hunger score, glucose, NEFA and GLP-1 between both intensities were observed. However, NEFA and GLP-1 plasma level were higher until 30 min post LI. In conclusion, the similarity of EE and oxidation outcomes could give overweight individuals an option to choose between intensities. However, HI could help to reduce EI. There are mechanisms and consequences of exercise in short and long-term appetite control; however, these mechanisms warrant further explanation. These results support the need for future research in to the role of in regulation energy balance, especially for obese people.

Keywords: appetite, exercise, food intake, energy expenditure

Procedia PDF Downloads 506
1181 A Synopsis of Green Energy Technology Implementation In South Africa

Authors: Sifiso Vilakazi, Lerato Mzenzi

Abstract:

BACKGROUND :- Human mind is a double-edged sword, it is both arduous and obtuse, vague and explicit. The neuroscience of brain has baffled all and left none. In this labyrinth, a novel neurotransmitter has set its foot. D-Aspartic acid, which has been established in rats and animals’ brain as a neurochemical in controlling behaviour, aggression, fertility, cognition and memory is set to formulate a new benchmark as a marker among suicidal and accidental death victims. Without losing sight of the fact, we have endeavoured to dig out the biochemical relation behind suicide in our research. We in our research have exerted to decipher the puzzle among humans for D-Aspartic acid using HPLC. METHODS:- We have taken 30 samples each of pre-frontal cortex of brain from suicide and road traffic accidents victims for our case-control research to establish brain D-Aspartic acid level using HPLC as a marker for suicide. RESULTS:- By using Independent/Unpaired T-Test Analysis:- The two-tailed P value is less than 0.0044. MEAN (mMOL/mL/G) for D-Aspartic acid in control is 24.2737±7.5958 and for cases is 19.5540±4.2647. By conventional criteria, this difference is considered to be extremely statistically significant. CONCLUSION:- (1) Brain D-Aspartic acid has an effect in the act of suicide and its values show a large drop before the act of suicide is commenced as compared to road traffic accidents which correlates with the study where D-AA was studied as a novel endogenous neurotransmitter in case of mental health disorders in humans, though never studied on suicide victims, likely getting it reference from research occurring on rats where it was discovered that D-AA plays a role in cognition, personality development, thought process, aggression. (2)The other study which was related to humans and signified the role of D-AA in reproduction, where low D-AA leads to infertility and depression and hence providing the much needed proof of role of D-AA in mental health disorders and suicide, and subsequently to the act of suicide.

Keywords: green energy, policy, technology, implementation

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1180 Drought Detection and Water Stress Impact on Vegetation Cover Sustainability Using Radar Data

Authors: E. Farg, M. M. El-Sharkawy, M. S. Mostafa, S. M. Arafat

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Mapping water stress provides important baseline data for sustainable agriculture. Recent developments in the new Sentinel-1 data which allow the acquisition of high resolution images and varied polarization capabilities. This study was conducted to detect and quantify vegetation water content from canopy backscatter for extracting spatial information to encourage drought mapping activities throughout new reclaimed sandy soils in western Nile delta, Egypt. The performance of radar imagery in agriculture strongly depends on the sensor polarization capability. The dual mode capabilities of Sentinel-1 improve the ability to detect water stress and the backscatter from the structure components improves the identification and separation of vegetation types with various canopy structures from other features. The fieldwork data allowed identifying of water stress zones based on land cover structure; those classes were used for producing harmonious water stress map. The used analysis techniques and results show high capability of active sensors data in water stress mapping and monitoring especially when integrated with multi-spectral medium resolution images. Also sub soil drip irrigation systems cropped areas have lower drought and water stress than center pivot sprinkler irrigation systems. That refers to high level of evaporation from soil surface in initial growth stages. Results show that high relationship between vegetation indices such as Normalized Difference Vegetation Index NDVI the observed radar backscattering. In addition to observational evidence showed that the radar backscatter is highly sensitive to vegetation water stress, and essentially potential to monitor and detect vegetative cover drought.

Keywords: canopy backscatter, drought, polarization, NDVI

Procedia PDF Downloads 145
1179 Mango (Mangifera indica L.) Lyophilization Using Vacuum-Induced Freezing

Authors: Natalia A. Salazar, Erika K. Méndez, Catalina Álvarez, Carlos E. Orrego

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Lyophilization, also called freeze-drying, is an important dehydration technique mainly used for pharmaceuticals. Food industry also uses lyophilization when it is important to retain most of the nutritional quality, taste, shape and size of dried products and to extend their shelf life. Vacuum-Induced during freezing cycle (VI) has been used in order to control ice nucleation and, consequently, to reduce the time of primary drying cycle of pharmaceuticals preserving quality properties of the final product. This procedure has not been applied in freeze drying of foods. The present work aims to investigate the effect of VI on the lyophilization drying time, final moisture content, density and reconstitutional properties of mango (Mangifera indica L.) slices (MS) and mango pulp-maltodextrin dispersions (MPM) (30% concentration of total solids). Control samples were run at each freezing rate without using induced vacuum. The lyophilization endpoint was the same for all treatments (constant difference between capacitance and Pirani vacuum gauges). From the experimental results it can be concluded that at the high freezing rate (0.4°C/min) reduced the overall process time up to 30% comparing process time required for the control and VI of the lower freeze rate (0.1°C/min) without affecting the quality characteristics of the dried product, which yields a reduction in costs and energy consumption for MS and MPM freeze drying. Controls and samples treated with VI at freezing rate of 0.4°C/min in MS showed similar results in moisture and density parameters. Furthermore, results from MPM dispersion showed favorable values when VI was applied because dried product with low moisture content and low density was obtained at shorter process time compared with the control. There were not found significant differences between reconstitutional properties (rehydration for MS and solubility for MPM) of freeze dried mango resulting from controls, and VI treatments.

Keywords: drying time, lyophilization, mango, vacuum induced freezing

Procedia PDF Downloads 410
1178 Effect of Print Orientation on the Mechanical Properties of Multi Jet Fusion Additively Manufactured Polyamide-12

Authors: Tyler Palma, Praveen Damasus, Michael Munther, Mehrdad Mohsenizadeh, Keivan Davami

Abstract:

The advancement of additive manufacturing, in both research and commercial realms, is highly dependent upon continuing innovations and creativity in materials and designs. Additive manufacturing shows great promise towards revolutionizing various industries, due largely to the fact that design data can be used to create complex products and components, on demand and from the raw materials, for the end user at the point of use. However, it will be critical that the material properties of additively-made parts for engineering purposes be fully understood. As it is a relatively new additive manufacturing method, the response of properties of Multi Jet Fusion (MJF) produced parts to different printing parameters has not been well studied. In this work, testing of mechanical and tribological properties MJF-printed Polyamide 12 parts was performed to determine whether printing orientation in this method results in significantly different part performances. Material properties were studied at macro- and nanoscales. Tensile tests, in combination with tribology tests including steady-state wear, were performed. Results showed a significant difference in resultant part characteristics based on whether they were printed in a vertical or horizontal orientation. Tensile performance of vertically and horizontally printed samples varied, both in ultimate strength and strain. Tribology tests showed that printing orientation has notable effects on the resulting mechanical and wear properties of tested surfaces, due largely to layer orientation and the presence of unfused fused powder grain inclusions. This research advances the understanding of how print orientation affects the mechanical properties of additively manufactured structures, and also how print orientation can be exploited in future engineering design.

Keywords: additive manufacturing, indentation, nano mechanical characterization, print orientation

Procedia PDF Downloads 138
1177 The Reliability Analysis of Concrete Chimneys Due to Random Vortex Shedding

Authors: Saba Rahman, Arvind K. Jain, S. D. Bharti, T. K. Datta

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Chimneys are generally tall and slender structures with circular cross-sections, due to which they are highly prone to wind forces. Wind exerts pressure on the wall of the chimneys, which produces unwanted forces. Vortex-induced oscillation is one of such excitations which can lead to the failure of the chimneys. Therefore, vortex-induced oscillation of chimneys is of great concern to researchers and practitioners since many failures of chimneys due to vortex shedding have occurred in the past. As a consequence, extensive research has taken place on the subject over decades. Many laboratory experiments have been performed to verify the theoretical models proposed to predict vortex-induced forces, including aero-elastic effects. Comparatively, very few proto-type measurement data have been recorded to verify the proposed theoretical models. Because of this reason, the theoretical models developed with the help of experimental laboratory data are utilized for analyzing the chimneys for vortex-induced forces. This calls for reliability analysis of the predictions of the responses of the chimneys produced due to vortex shedding phenomena. Although several works of literature exist on the vortex-induced oscillation of chimneys, including code provisions, the reliability analysis of chimneys against failure caused due to vortex shedding is scanty. In the present study, the reliability analysis of chimneys against vortex shedding failure is presented, assuming the uncertainty in vortex shedding phenomena to be significantly more than other uncertainties, and hence, the latter is ignored. The vortex shedding is modeled as a stationary random process and is represented by a power spectral density function (PSDF). It is assumed that the vortex shedding forces are perfectly correlated and act over the top one-third height of the chimney. The PSDF of the tip displacement of the chimney is obtained by performing a frequency domain spectral analysis using a matrix approach. For this purpose, both chimney and random wind forces are discretized over a number of points along with the height of the chimney. The method of analysis duly accounts for the aero-elastic effects. The double barrier threshold crossing level, as proposed by Vanmarcke, is used for determining the probability of crossing different threshold levels of the tip displacement of the chimney. Assuming the annual distribution of the mean wind velocity to be a Gumbel type-I distribution, the fragility curve denoting the variation of the annual probability of threshold crossing against different threshold levels of the tip displacement of the chimney is determined. The reliability estimate is derived from the fragility curve. A 210m tall concrete chimney with a base diameter of 35m, top diameter as 21m, and thickness as 0.3m has been taken as an illustrative example. The terrain condition is assumed to be that corresponding to the city center. The expression for the PSDF of the vortex shedding force is taken to be used by Vickery and Basu. The results of the study show that the threshold crossing reliability of the tip displacement of the chimney is significantly influenced by the assumed structural damping and the Gumbel distribution parameters. Further, the aero-elastic effect influences the reliability estimate to a great extent for small structural damping.

Keywords: chimney, fragility curve, reliability analysis, vortex-induced vibration

Procedia PDF Downloads 161
1176 Exploring the Efficacy of Context-Based Instructional Strategy in Fostering Students Achievement in Chemistry

Authors: Charles U. Eze, Joy Johnbest Egbo

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The study investigated the effect of Context-Based Instructional Strategy (CBIS) on students’ achievement in chemistry. CBIS was used as an experimental group and expository method (EM) as a control group, sources showed that students poor achievement in chemistry is from teaching strategy adopted by the chemistry teachers. Two research questions were answered, and two null hypotheses were formulated and tested. This strategy recognizes the need for student-centered, relevance of tasks and students’ voice; it also helps students develop creative and critical learning skills. A quasi-experimental (non-equivalent, pretest, posttest control group) design was adopted for the study. The population for the study comprised all senior secondary class one (SSI) students who were offering chemistry in co-education schools in Agbani Education zone. The instrument for data collection was a self-developed Basic Chemistry Achievement Test (BCAT). Relevant data were collected from a sample of SSI chemistry students using purposive random sampling techniques from two co-education schools in Agbani Education Zone of Enugu State, Nigeria. A reliability co-efficient was obtained for the instrument using Kuder-Richardson formula 20. Mean and standard deviation scores were used to answer the research questions while two-way analysis of covariance (ANCOVA) was used to test the hypotheses. The findings showed that the experimental group taught with context-based instructional strategy (CBIS) obtained a higher mean achievement score than the control group in the post BCAT; male students had higher mean achievement scores than their female counterparts. The difference was significant. It was recommended, among others, that CBIS should be given more emphasis in the training and re-training program of secondary school chemistry teachers.

Keywords: context-based instructional strategy, expository strategy, student-centered

Procedia PDF Downloads 229
1175 Numerical Optimization of Cooling System Parameters for Multilayer Lithium Ion Cell and Battery Packs

Authors: Mohammad Alipour, Ekin Esen, Riza Kizilel

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Lithium-ion batteries are a commonly used type of rechargeable batteries because of their high specific energy and specific power. With the growing popularity of electric vehicles and hybrid electric vehicles, increasing attentions have been paid to rechargeable Lithium-ion batteries. However, safety problems, high cost and poor performance in low ambient temperatures and high current rates, are big obstacles for commercial utilization of these batteries. By proper thermal management, most of the mentioned limitations could be eliminated. Temperature profile of the Li-ion cells has a significant role in the performance, safety, and cycle life of the battery. That is why little temperature gradient can lead to great loss in the performances of the battery packs. In recent years, numerous researchers are working on new techniques to imply a better thermal management on Li-ion batteries. Keeping the battery cells within an optimum range is the main objective of battery thermal management. Commercial Li-ion cells are composed of several electrochemical layers each consisting negative-current collector, negative electrode, separator, positive electrode, and positive current collector. However, many researchers have adopted a single-layer cell to save in computing time. Their hypothesis is that thermal conductivity of the layer elements is so high and heat transfer rate is so fast. Therefore, instead of several thin layers, they model the cell as one thick layer unit. In previous work, we showed that single-layer model is insufficient to simulate the thermal behavior and temperature nonuniformity of the high-capacity Li-ion cells. We also studied the effects of the number of layers on thermal behavior of the Li-ion batteries. In this work, first thermal and electrochemical behavior of the LiFePO₄ battery is modeled with 3D multilayer cell. The model is validated with the experimental measurements at different current rates and ambient temperatures. Real time heat generation rate is also studied at different discharge rates. Results showed non-uniform temperature distribution along the cell which requires thermal management system. Therefore, aluminum plates with mini-channel system were designed to control the temperature uniformity. Design parameters such as channel number and widths, inlet flow rate, and cooling fluids are optimized. As cooling fluids, water and air are compared. Pressure drop and velocity profiles inside the channels are illustrated. Both surface and internal temperature profiles of single cell and battery packs are investigated with and without cooling systems. Our results show that using optimized Mini-channel cooling plates effectively controls the temperature rise and uniformity of the single cells and battery packs. With increasing the inlet flow rate, cooling efficiency could be reached up to 60%.

Keywords: lithium ion battery, 3D multilayer model, mini-channel cooling plates, thermal management

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1174 The Role of Human Cartilage Glycoprotein in Osteoporosis and Osteoporotic Fractures

Authors: Hasanzade Nazenin, Hasanova Naila

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According to the WHO, osteoporosis is one of the most important health problems in the world and occupies the 4th place in its importance after cardiovascular pathology, oncological diseases and diabetes mellitus. The significance of osteoporosis is determined by its prevalence among the population, the severity of the course, the cause of death, disability, reduced quality of life, high economic costs for prevention and treatment. Osteoporosis is a systemic skeletal disease characterized by a decrease in bone mass and a violation of the structure of bone tissue, leading to an increase in bone fragility and the risk of fractures. Osteoporosis is manifested by low-traumatic fractures. Due to the complexity of the recovery process, the treatment of osteoporotic fractures is one of the important problems of modern traumatology. Diagnostic markers are needed to monitor the recovery period. Human cartilage glycoprotein -39, which has been studied so far in inflammatory processes in the bones, may allow the development of the correct treatment regimen, reflecting the level of metabolic processes in the bone tissue. The study was performed to examine the dynamics of human cartilage glycoprotein-39 (HCgp39) in the blood serum during osteoporosis and fracture healing. The material of the study is formed by the examination results of 68 people aged 38-83. Group I - control group consisted of 14 practically healthy people, group II - 14 patients with osteoporosis, group III - 15 patients with non-osteoporotic fractures, group IV - 25 patients with osteoporotic fractures. In groups, they were analyzed by enzyme-linked immunosorbent assay 3 times during the first month. As a result, in the first month of the recovery period, no significant difference was observed in the HCgp39 dynamics for groups II and IV (p> 0.05). However, there was a significant reduction in group III (p <0.05). As no osteoporotic changes were observed in this patient group, bone healing was rapid and it was possible to monitor the dynamics of HCgp39 changes within 1 month. Patients with osteoporosis and other bone fractures in the process of complete recovery need to study HCgp39 more as a diagnostic indicator.

Keywords: osteoporosis, osteoporotic fractures, human cartilage glycoprotein, HCgp39

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1173 Urinary Exosome miR-30c-5p as a Biomarker for Early-Stage Clear Cell Renal Cell Carcinoma

Authors: Shangqing Song, Bin Xu, Yajun Cheng, Zhong Wang

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miRNAs derived from exosomes exist in a body fluid such as urine were regarded as potential biomarkers for various human cancers diagnosis and prognosis, as mature miRNAs can be steadily preserved by exosomes. However, its potential value in clear cell renal cell carcinoma (ccRCC) diagnosis and prognosis remains unclear. In the present study, differentially expressed miRNAs from urinal exosomes were identified by next-generation sequencing (NGS) technology. The 16 differentially expressed miRNAs were identified between ccRCC patients and healthy donors. To explore the specific diagnosis biomarker of ccRCC, we validated these urinary exosomes from 70 early-stage renal cancer patients, 30 healthy people and other urinary system cancers, including 30 early-stage prostate cancer patients and 30 early-stage bladder cancer patients by qRT-PCR. The results showed that urinary exosome miR-30c-5p could be stably amplified and meanwhile the expression of miR-30c-5p has no significant difference between other urinary system cancers and healthy control, however, expression level of miR-30c-5p in urinary exosomal of ccRCC patients was lower than healthy people and receiver operation characterization (ROC) curve showed that the area under the curve (AUC) values was 0.8192 (95% confidence interval was 0.7388-0.8996, P= 0.0000). In addition, up-regulating miR-30c-5p expression could inhibit renal cell carcinoma cells growth. Lastly, HSP5A was found as a direct target gene of miR-30c-5p. HSP5A depletion reversed the promoting effect of ccRCC growth casued by miR-30c-5p inhibitor, respectively. In conclusion, this study demonstrated that urinary exosomal miR-30c-5p is readily accessible as diagnosis biomarker of early-stage ccRCC, and miR-30c-5p might modulate the expression of HSPA5, which correlated with the progression of ccRCC.

Keywords: clear cell renal cell carcinoma, exosome, HSP5A, miR-30c-5p

Procedia PDF Downloads 267