Search results for: integrative design process
1090 Accumulated Gender-Diverse Co-signing Experience, Knowledge Sharing, and Audit Quality
Authors: Anxuan Xie, Chun-Chan Yu
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Survey evidence provides support that auditors can gain professional knowledge not only from client firms but also from teammates they work with. Furthermore, given that knowledge is accumulated in nature, along with the reality that auditors today must work in an environment of increased diversity, whether the attributes of teammates will influence the effects of knowledge sharing and accumulation and ultimately influence an audit partner’s audit quality should be interesting research issues. We test whether the gender of co-signers will moderate the effect of a lead partner’s cooperative experiences on financial restatements. Furthermore, if the answer is “yes”, we further investigate the underlying reasons. We use data from Taiwan because, according to Taiwan’s law, engagement partners, who are basically two certificate public accountants from the same audit firm, are required to disclose (i.e., sign) their names in the audit report of public companies since 1983. Therefore, we can trace each engagement partner’s historic direct cooperative (co-signing) records and get large-sample data. We find that the benefits of knowledge sharing manifest primarily via co-signing audit reports with audit partners of different gender from the lead engagement partners, supporting the argument that in an audit setting, accumulated gender-diverse working relationship is positively associated with knowledge sharing, and therefore improve lead engagements’ audit quality. This study contributes to the extant literature in the following ways. First, we provide evidence that in the auditing setting, the experiences accumulated from cooperating with teammates of a different gender from the lead partner can improve audit quality. Given that most studies find evidence of negative effects of surface-level diversity on team performance, the results of this study support the prior literature that the association between diversity and knowledge sharing actually hinges on the context (e.g., organizational culture, task complexity) and “bridge” (a pre-existing commonality among team members that can smooth the process of diversity toward favorable results) among diversity team members. Second, this study also provides practical insights with respect to the audit firms’ policy of knowledge sharing and deployment of engagement partners. For example, for audit firms that appreciate the merits of knowledge sharing, the deployment of auditors of different gender within an audit team can help auditors accumulate audit-related knowledge, which will further benefit the future performance of those audit firms. Moreover, nowadays, client firms also attach importance to the diversity of their engagement partners. As their policy goals, lawmakers and regulators also continue to promote a gender-diverse working environment. The findings of this study indicate that for audit firms, gender diversity will not be just a means to cater to those groups. Third, for audit committees or other stakeholders, they can evaluate the quality of existing (or potential) lead partners by tracking their co-signing experiences, especially whether they have gender-diverse co-signing experiences.Keywords: co-signing experiences, audit quality, knowledge sharing, gender diversity
Procedia PDF Downloads 841089 Role of Vitamin-D in Reducing Need for Supplemental Oxygen Among COVID-19 Patients
Authors: Anita Bajpai, Sarah Duan, Ashlee Erskine, Shehzein Khan, Raymond Kramer
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Introduction: This research focuses on exploring the beneficial effects if any, of Vitamin-D in reducing the need for supplemental oxygen among hospitalized COVID-19 patients. Two questions are investigated – Q1)Doeshaving a healthy level of baselineVitamin-D 25-OH (≥ 30ng/ml) help,andQ2) does administering Vitamin-D therapy after-the-factduring inpatient hospitalization help? Methods/Study Design: This is a comprehensive, retrospective, observational study of all inpatients at RUHS from March through December 2020 who tested positive for COVID-19 based on real-time reverse transcriptase–polymerase chain reaction assay of nasal and pharyngeal swabs and rapid assay antigen test. To address Q1, we looked atall N1=182 patients whose baseline plasma Vitamin-D 25-OH was known and who needed supplemental oxygen. Of this, a total of 121 patients had a healthy Vitamin-D level of ≥30 ng/mlwhile the remaining 61 patients had low or borderline (≤ 29.9ng/ml)level. Similarly, for Q2, we looked at a total of N2=893 patients who were given supplemental oxygen, of which713 were not given Vitamin-D and 180 were given Vitamin-D therapy. The numerical value of the maximum amount of oxygen flow rate(dependent variable) administered was recorded for each patient. The mean values and associated standard deviations for each group were calculated. Thesetwo sets of independent data served as the basis for independent, two-sample t-Test statistical analysis. To be accommodative of any reasonable benefitof Vitamin-D, ap-value of 0.10(α< 10%) was set as the cutoff point for statistical significance. Results: Given the large sample sizes, the calculated statistical power for both our studies exceeded the customary norm of 80% or better (β< 0.2). For Q1, the mean value for maximumoxygen flow rate for the group with healthybaseline level of Vitamin-D was 8.6 L/min vs.12.6L/min for those with low or borderline levels, yielding a p-value of 0.07 (p < 0.10) with the conclusion that those with a healthy level of baseline Vitamin-D needed statistically significant lower levels of supplemental oxygen. ForQ2, the mean value for a maximum oxygen flow rate for those not administered Vitamin-Dwas 12.5 L/min vs.12.8L/min for those given Vitamin-D, yielding a p-valueof 0.87 (p > 0.10). We thereforeconcludedthat there was no statistically significant difference in the use of oxygen therapy between those who were or were not administered Vitamin-D after-the-fact in the hospital. Discussion/Conclusion: We found that patients who had healthy levels of Vitamin-D at baseline needed statistically significant lower levels of supplemental oxygen. Vitamin-D is well documented, including in a recent article in the Lancet, for its anti-inflammatory role as an adjuvant in the regulation of cytokines and immune cells. Interestingly, we found no statistically significant advantage for giving Vitamin-D to hospitalized patients. It may be a case of “too little too late”. A randomized clinical trial reported in JAMA also did not find any reduction in hospital stay of patients given Vitamin-D. Such conclusions come with a caveat that any delayed marginal benefits may not have materialized promptly in the presence of a significant inflammatory condition. Since Vitamin-D is a low-cost, low-risk option, it may still be useful on an inpatient basis until more definitive findings are established.Keywords: COVID-19, vitamin-D, supplemental oxygen, vitamin-D in primary care
Procedia PDF Downloads 1521088 Effects of Tramadol Administration on the Ovary of Adult Rats and the Possible Recovery after Tramadol Withdrawal: A Light and Electron Microscopic Study
Authors: Heba Kamal Mohamed
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Introduction: Tramadol is a weak -opioid receptor agonist with an analgesic effect because of the inhibition of uptake of norepinephrine and serotonin. Nowadays, tramadol hydrochloride is frequently used as a pain reliever. Tramadol is recommended for the management of acute and chronic pain of moderate to severe intensity associated with a variety of diseases or problems, including osteoarthritis, diabetic neuropathy, neuropathic pain, and even perioperative pain in human patients. In obstetrics and gynecology, tramadol is used extensively to treat postoperative pain. Aim of the study: This study was undertaken to investigate the histological (light and electron microscopic) and immunohistochemical effects of long term tramadol treatment on the ovary of adult rats and the possible recovery after tramadol withdrawal. Design: Experimental study. Materials and methods: Thirty adult female albino rats were used in this study. They were classified into three main groups (10 rats each). Group I served as the control group. Group II, rats were subcutaneously injected with tramadol 40 mg/kg three times per week for 8 weeks. Group III, rats were subcutaneously injected with tramadol 40 mg/kg three times per week for 8 weeks then were kept for another 8 weeks without treatment for recovery. At the end of the experiment rats were sacrificed and bilateral oophorectomy was carried out; the ovaries were processed for histological study (light and electron microscopic) and immunohistochemical reaction for caspase-3 (apoptotic protein). Results: Examination of the ovary of tramadol-treated rats (group II) revealed many atretic ovarian follicles, some follicles showed detachment of the oocyte from surrounding granulosa cells and others showed loss of the oocyte. Many follicles revealed degenerated vacuolated oocytes and vacuolated theca folliculi cells. Granulosa cells appeared shrunken, disrupted and loosely attached with vacuolated cytoplasm and pyknotic nuclei. Some follicles showed separation of granulosa cells from the theca folliculi layer. The ultrastructural study revealed the presence of granulosa cells with electron dense indented nuclei, damaged mitochondria and granular vacuolated cytoplasm. Other cells showed accumulation of large amount of lipid droplets in their cytoplasm. Some follicles revealed rarifaction of the cytoplasm of oocytes and absent zona pellucida. Moreover, apoptotic changes were detected by immunohistochemical staining in the form of increased staining intensity to caspase-3 (apoptotic protein). With Masson's Trichrome stain, there was an increased collagen fibre deposition in the ovarian cortical stroma. The wall of blood vessels appeared thickened. In the withdrawal group (group III), there was a little improvement in the histological and immunohistochemical changes. Conclusion: Tramadol had serious deleterious effects on ovarian structure. Thus, it should be used with caution, especially when a long term treatment is indicated. Withdrawal of tramadol led to a little improvement in the structural impairment of the ovary.Keywords: tramadol, ovary, withdrawal, rats
Procedia PDF Downloads 2921087 In-Situ Formation of Particle Reinforced Aluminium Matrix Composites by Laser Powder Bed Fusion of Fe₂O₃/AlSi12 Powder Mixture Using Consecutive Laser Melting+Remelting Strategy
Authors: Qimin Shi, Yi Sun, Constantinus Politis, Shoufeng Yang
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In-situ preparation of particle-reinforced aluminium matrix composites (PRAMCs) by laser powder bed fusion (LPBF) additive manufacturing is a promising strategy to strengthen traditional Al-based alloys. The laser-driven thermite reaction can be a practical mechanism to in-situ synthesize PRAMCs. However, introducing oxygen elements through adding Fe₂O₃ makes the powder mixture highly sensitive to form porosity and Al₂O₃ film during LPBF, bringing challenges to producing dense Al-based materials. Therefore, this work develops a processing strategy combined with consecutive high-energy laser melting scanning and low-energy laser remelting scanning to prepare PRAMCs from a Fe₂O₃/AlSi12 powder mixture. The powder mixture consists of 5 wt% Fe₂O₃ and the remainder AlSi12 powder. The addition of 5 wt% Fe₂O₃ aims to achieve balanced strength and ductility. A high relative density (98.2 ± 0.55 %) was successfully obtained by optimizing laser melting (Emelting) and laser remelting surface energy density (Eremelting) to Emelting = 35 J/mm² and Eremelting = 5 J/mm². Results further reveal the necessity of increasing Emelting, to improve metal liquid’s spreading/wetting by breaking up the Al₂O₃ films surrounding the molten pools; however, the high-energy laser melting produced much porosity, including H₂₋, O₂₋ and keyhole-induced pores. The subsequent low-energy laser remelting could close the resulting internal pores, backfill open gaps and smoothen solidified surfaces. As a result, the material was densified by repeating laser melting and laser remelting layer by layer. Although with two-times laser scanning, the microstructure still shows fine cellular Si networks with Al grains inside (grain size of about 370 nm) and in-situ nano-precipitates (Al₂O₃, Si, and Al-Fe(-Si) intermetallics). Finally, the fine microstructure, nano-structured dispersion strengthening, and high-level densification strengthened the in-situ PRAMCs, reaching yield strength of 426 ± 4 MPa and tensile strength of 473 ± 6 MPa. Furthermore, the results can expect to provide valuable information to process other powder mixtures with severe porosity/oxide-film formation potential, considering the evidenced contribution of laser melting/remelting strategy to densify material and obtain good mechanical properties during LPBF.Keywords: densification, laser powder bed fusion, metal matrix composites, microstructures, mechanical properties
Procedia PDF Downloads 1551086 Modeling of Anisotropic Hardening Based on Crystal Plasticity Theory and Virtual Experiments
Authors: Bekim Berisha, Sebastian Hirsiger, Pavel Hora
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Advanced material models involving several sets of model parameters require a big experimental effort. As models are getting more and more complex like e.g. the so called “Homogeneous Anisotropic Hardening - HAH” model for description of the yielding behavior in the 2D/3D stress space, the number and complexity of the required experiments are also increasing continuously. In the context of sheet metal forming, these requirements are even more pronounced, because of the anisotropic behavior or sheet materials. In addition, some of the experiments are very difficult to perform e.g. the plane stress biaxial compression test. Accordingly, tensile tests in at least three directions, biaxial tests and tension-compression or shear-reverse shear experiments are performed to determine the parameters of the macroscopic models. Therefore, determination of the macroscopic model parameters based on virtual experiments is a very promising strategy to overcome these difficulties. For this purpose, in the framework of multiscale material modeling, a dislocation density based crystal plasticity model in combination with a FFT-based spectral solver is applied to perform virtual experiments. Modeling of the plastic behavior of metals based on crystal plasticity theory is a well-established methodology. However, in general, the computation time is very high and therefore, the computations are restricted to simplified microstructures as well as simple polycrystal models. In this study, a dislocation density based crystal plasticity model – including an implementation of the backstress – is used in a spectral solver framework to generate virtual experiments for three deep drawing materials, DC05-steel, AA6111-T4 and AA4045 aluminum alloys. For this purpose, uniaxial as well as multiaxial loading cases, including various pre-strain histories, has been computed and validated with real experiments. These investigations showed that crystal plasticity modeling in the framework of Representative Volume Elements (RVEs) can be used to replace most of the expensive real experiments. Further, model parameters of advanced macroscopic models like the HAH model can be determined from virtual experiments, even for multiaxial deformation histories. It was also found that crystal plasticity modeling can be used to model anisotropic hardening more accurately by considering the backstress, similar to well-established macroscopic kinematic hardening models. It can be concluded that an efficient coupling of crystal plasticity models and the spectral solver leads to a significant reduction of the amount of real experiments needed to calibrate macroscopic models. This advantage leads also to a significant reduction of computational effort needed for the optimization of metal forming process. Further, due to the time efficient spectral solver used in the computation of the RVE models, detailed modeling of the microstructure are possible.Keywords: anisotropic hardening, crystal plasticity, micro structure, spectral solver
Procedia PDF Downloads 3131085 Blending Synchronous with Asynchronous Learning Tools: Students’ Experiences and Preferences for Online Learning Environment in a Resource-Constrained Higher Education Situations in Uganda
Authors: Stephen Kyakulumbye, Vivian Kobusingye
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Generally, World over, COVID-19 has had adverse effects on all sectors but with more debilitating effects on the education sector. After reactive lockdowns, education institutions that could continue teaching and learning had to go a distance mediated by digital technological tools. In Uganda, the Ministry of Education thereby issued COVID-19 Online Distance E-learning (ODeL) emergent guidelines. Despite such guidelines, academic institutions in Uganda and similar developing contexts with academically constrained resource environments were caught off-guard and ill-prepared to transform from face-to-face learning to online distance learning mode. Most academic institutions that migrated spontaneously did so with no deliberate tools, systems, strategies, or software to cause active, meaningful, and engaging learning for students. By experience, most of these academic institutions shifted to Zoom and WhatsApp and instead conducted online teaching in real-time than blended synchronous and asynchronous tools. This paper provides students’ experiences while blending synchronous and asynchronous content-creating and learning tools within a technological resource-constrained environment to navigate in such a challenging Uganda context. These conceptual case-based findings, using experience from Uganda Christian University (UCU), point at the design of learning activities with two certain characteristics, the enhancement of synchronous learning technologies with asynchronous ones to mitigate the challenge of system breakdown, passive learning to active learning, and enhances the types of presence (social, cognitive and facilitatory). The paper, both empirical and experiential in nature, uses online experiences from third-year students in Bachelor of Business Administration student lectured using asynchronous text, audio, and video created with Open Broadcaster Studio software and compressed with Handbrake, all open-source software to mitigate disk space and bandwidth usage challenges. The synchronous online engagements with students were a blend of zoom or BigBlueButton, to ensure that students had an alternative just in case one failed due to excessive real-time traffic. Generally, students report that compared to their previous face-to-face lectures, the pre-recorded lectures via Youtube provided them an opportunity to reflect on content in a self-paced manner, which later on enabled them to engage actively during the live zoom and/or BigBlueButton real-time discussions and presentations. The major recommendation is that lecturers and teachers in a resource-constrained environment with limited digital resources like the internet and digital devices should harness this approach to offer students access to learning content in a self-paced manner and thereby enabling reflective active learning through reflective and high-order thinking.Keywords: synchronous learning, asynchronous learning, active learning, reflective learning, resource-constrained environment
Procedia PDF Downloads 1371084 Fabrication of Highly Conductive Graphene/ITO Transparent Bi-Film through Chemical Vapor Deposition (CVD) and Organic Additives-Free Sol-Gel Techniques
Authors: Bastian Waduge Naveen Harindu Hemasiri, Jae-Kwan Kim, Ji-Myon Lee
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Indium tin oxide (ITO) remains the industrial standard transparent conducting oxides with better performances. Recently, graphene becomes as a strong material with unique properties to replace the ITO. However, graphene/ITO hybrid composite material is a newly born field in the electronic world. In this study, the graphene/ITO composite bi-film was synthesized by a two steps process. 10 wt.% tin-doped, ITO thin films were produced by an environmentally friendly aqueous sol-gel spin coating technique with economical salts of In(NO3)3.H2O and SnCl4 without using organic additives. The wettability and surface free energy (97.6986 mJ/m2) enhanced oxygen plasma treated glass substrates were used to form voids free continuous ITO film. The spin-coated samples were annealed at 600 0C for 1 hour under low vacuum conditions to obtained crystallized, ITO film. The crystal structure and crystalline phases of ITO thin films were analyzed by X-ray diffraction (XRD) technique. The Scherrer equation was used to determine the crystallite size. Detailed information about chemical composition and elemental composition of the ITO film were determined by X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX) coupled with FE-SEM respectively. Graphene synthesis was done under chemical vapor deposition (CVD) method by using Cu foil at 1000 0C for 1 min. The quality of the synthesized graphene was characterized by Raman spectroscopy (532nm excitation laser beam) and data was collected at room temperature and normal atmosphere. The surface and cross-sectional observation were done by using FE-SEM. The optical transmission and sheet resistance were measured by UV-Vis spectroscopy and four point probe head at room temperature respectively. Electrical properties were also measured by using V-I characteristics. XRD patterns reveal that the films contain the In2O3 phase only and exhibit the polycrystalline nature of the cubic structure with the main peak of (222) plane. The peak positions of In3d5/2 (444.28 eV) and Sn3d5/2 (486.7 eV) in XPS results indicated that indium and tin are in the oxide form only. The UV-visible transmittance shows 91.35 % at 550 nm with 5.88 x 10-3 Ωcm specific resistance. The G and 2D band in Raman spectroscopy of graphene appear at 1582.52 cm-1 and 2690.54 cm-1 respectively when the synthesized CVD graphene on SiO2/Si. The determined intensity ratios of 2D to G (I2D/IG) and D to G (ID/IG) were 1.531 and 0.108 respectively. However, the above-mentioned G and 2D peaks appear at 1573.57 cm-1 and 2668.14 cm-1 respectively when the CVD graphene on the ITO coated glass, the positions of G and 2D peaks were red shifted by 8.948 cm-1 and 22.396 cm-1 respectively. This graphene/ITO bi-film shows modified electrical properties when compares with sol-gel derived ITO film. The reduction of sheet resistance in the bi-film was 12.03 % from the ITO film. Further, the fabricated graphene/ITO bi-film shows 88.66 % transmittance at 550 nm wavelength.Keywords: chemical vapor deposition, graphene, ITO, Raman Spectroscopy, sol-gel
Procedia PDF Downloads 2591083 Effect of Preconception Picture-Based Nutrition Education on Knowledge and Adherence to Iron-Folic Acid Supplementation Among Women Planning to Be Pregnant in Ethiopia
Authors: Anteneh Berhane Yeyi, Tefera Belachew
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Any woman who could become pregnant is at risk of having a baby with neural tube defects (NTDs). A spontaneous aborted women with immediately preceding pregnancy may have an increased risk of develop NTDs. Ethiopia has one of the highest rates of micronutrient deficiencies, including folate and iron deficiency. Currently, in Ethiopia, NTDs is emerged as a public health concern. Even if Ethiopia, has implement different strategies for reducing maternal and neonatal mortality and morbidity, there is no room in the health care system and lack of integration for preventing the risk of NTDs for those women who aborted spontaneously and women who discontinue long acting contraception to become pregnant. The purpose of this study was to evaluate the effect of preconception picture-based nutrition education on knowledge and adherence to iron-folic acid supplement (IFAS) intake to reduce the risk of developing neural tube defects (NTDs) and iron deficiency anemia (IDA) among women who had a planned to pregnancy in Ethiopia, a country with a high burden of NTDs. Methodology: This study was conducted in Eastern Ethiopia. A double blinded parallel randomized controlled trial design was employed among women in the age group of 18-45 years who requested to interrupt modern contraceptive who have an intention to be pregnant and women with spontaneous abortion who refused to take a contraceptive. The interventional arm (n=122) received a preconception picture-based nutrition education with iron-folic acid supplement, and the control arm (n=122) received only preconception IFAS. In this study male partners were participated. Result: After three months of intervention the proportion of adherence to IFAS was 23% (n=56). With regard to adherence within the groups, 42.6% (n=52) in the intervention group and 3.3% (n=4) in the control group and the intervention group were significantly higher than in control group. In the intervention group the proportion of adherence to IFAS intake among participants increased by 40.1% and there were statistically difference (P<0.0001). The difference in difference between the two groups of adherence to IFAS intake was 37.6% and there were a statistical significance (P<0.0001). Level of knowledge between the groups did differ before and after intervention (P= 0.87 Vs P<0.0001). The overall the mean change in knowledge Mean (+SE) between group was 0.9 (+3.04 SE) and there were significant differences between two groups (P<0.001). Conclusion: In general this intervention is effective toward adherence to IFAS and a critical milestone to improve maternal health and reduce the neonate mortality due to NTDs and other advert effect of pregnancy and birth outcomes. This intervention is very short, simple, and cost effective and has potential for adaptation, feasible development to large-scale implementation in the existing health care system. Furthermore, this type of interventional approach has the potential to reduce the country's ANC program dropout rates and increase male partner’s participation on reproductive health.Keywords: NTDs, IFAS, WRA, Ethiopia
Procedia PDF Downloads 341082 Investigation of Fluid-Structure-Seabed Interaction of Gravity Anchor Under Scour, and Anchor Transportation and Installation (T&I)
Authors: Vinay Kumar Vanjakula, Frank Adam
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The generation of electricity through wind power is one of the leading renewable energy generation methods. Due to abundant higher wind speeds far away from shore, the construction of offshore wind turbines began in the last decades. However, the installation of offshore foundation-based (monopiles) wind turbines in deep waters are often associated with technical and financial challenges. To overcome such challenges, the concept of floating wind turbines is expanded as the basis of the oil and gas industry. For such a floating system, stabilization in harsh conditions is a challenging task. For that, a robust heavy-weight gravity anchor is needed. Transportation of such anchor requires a heavy vessel that increases the cost. To lower the cost, the gravity anchor is designed with ballast chambers that allow the anchor to float while towing and filled with water when lowering to the planned seabed location. The presence of such a large structure may influence the flow field around it. The changes in the flow field include, formation of vortices, turbulence generation, waves or currents flow breaking and pressure differentials around the seabed sediment. These changes influence the installation process. Also, after installation and under operating conditions, the flow around the anchor may allow the local seabed sediment to be carried off and results in Scour (erosion). These are a threat to the structure's stability. In recent decades, rapid developments of research work and the knowledge of scouring on fixed structures (bridges and monopiles) in rivers and oceans have been carried out, and very limited research work on scouring around a bluff-shaped gravity anchor. The objective of this study involves the application of different numerical models to simulate the anchor towing under waves and calm water conditions. Anchor lowering involves the investigation of anchor movements at certain water depths under wave/current. The motions of anchor drift, heave, and pitch is of special focus. The further study involves anchor scour, where the anchor is installed in the seabed; the flow of underwater current around the anchor induces vortices mainly at the front and corners that develop soil erosion. The study of scouring on a submerged gravity anchor is an interesting research question since the flow not only passes around the anchor but also over the structure that forms different flow vortices. The achieved results and the numerical model will be a basis for the development of other designs and concepts for marine structures. The Computational Fluid Dynamics (CFD) numerical model will build in OpenFOAM and other similar software.Keywords: anchor lowering, anchor towing, gravity anchor, computational fluid dynamics, scour
Procedia PDF Downloads 1681081 Disaster Management Approach for Planning an Early Response to Earthquakes in Urban Areas
Authors: Luis Reynaldo Mota-Santiago, Angélica Lozano
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Determining appropriate measures to face earthquakesarea challenge for practitioners. In the literature, some analyses consider disaster scenarios, disregarding some important field characteristics. Sometimes, software that allows estimating the number of victims and infrastructure damages is used. Other times historical information of previous events is used, or the scenarios’informationis assumed to be available even if it isnot usual in practice. Humanitarian operations start immediately after an earthquake strikes, and the first hours in relief efforts are important; local efforts are critical to assess the situation and deliver relief supplies to the victims. A preparation action is prepositioning stockpiles, most of them at central warehouses placed away from damage-prone areas, which requires large size facilities and budget. Usually, decisions in the first 12 hours (standard relief time (SRT)) after the disaster are the location of temporary depots and the design of distribution paths. The motivation for this research was the delay in the reaction time of the early relief efforts generating the late arrival of aid to some areas after the Mexico City 7.1 magnitude earthquake in 2017. Hence, a preparation approach for planning the immediate response to earthquake disasters is proposed, intended for local governments, considering their capabilities for planning and for responding during the SRT, in order to reduce the start-up time of immediate response operations in urban areas. The first steps are the generation and analysis of disaster scenarios, which allow estimatethe relief demand before and in the early hours after an earthquake. The scenarios can be based on historical data and/or the seismic hazard analysis of an Atlas of Natural Hazards and Risk as a way to address the limited or null available information.The following steps include the decision processes for: a) locating local depots (places to prepositioning stockpiles)and aid-giving facilities at closer places as possible to risk areas; and b) designing the vehicle paths for aid distribution (from local depots to the aid-giving facilities), which can be used at the beginning of the response actions. This approach allows speeding up the delivery of aid in the early moments of the emergency, which could reduce the suffering of the victims allowing additional time to integrate a broader and more streamlined response (according to new information)from national and international organizations into these efforts. The proposed approachis applied to two case studies in Mexico City. These areas were affectedby the 2017’s earthquake, having limited aid response. The approach generates disaster scenarios in an easy way and plans a faster early response with a short quantity of stockpiles which can be managed in the early hours of the emergency by local governments. Considering long-term storage, the estimated quantities of stockpiles require a limited budget to maintain and a small storage space. These stockpiles are useful also to address a different kind of emergencies in the area.Keywords: disaster logistics, early response, generation of disaster scenarios, preparation phase
Procedia PDF Downloads 1091080 Erasmus+ Program in Vocational Education: Effects of European International Mobility in Portuguese Vocational Schools
Authors: José Carlos Bronze, Carlinda Leite, Angélica Monteiro
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The creation of the Erasmus Program in 1987 represented a milestone in promoting and funding international mobility in higher education in Europe. Its effects were so significant that they influenced the creation of the European Higher Education Area through the Bologna Process and ensured the program’s continuation and maintenance. Over the last decades, the escalating figures of participants and funds instigated significant scientific studies on the program's effects on higher education. More recently, in 2014, the program was renamed “Erasmus+” when it expanded into other fields of education, namely Vocational Education and Training (VET). Despite being now running in this field of education for a decade (2014-2024), its effects on VET remain less studied and less known, while the higher education field keeps attracting researchers’ attention. Given this gap, it becomes relevant to study the effects of E+ on VET, particularly in the priority domains of the Program: “Inclusion and Diversity,” “Participation in Democratic Life, Common Values and Civic Engagement,” “Environment and Fight Against Climate Change,” and “Digital Transformation.” This latter has been recently emphasized due to the COVID-19 pandemic that forced the so-called emergency remote teaching, leading schools to quickly transform and adapt to a new reality regardless of the preparedness levels of teachers and students. Together with the remaining E+ priorities, they directly relate to an emancipatory perspective of education sustained in soft skills such as critical thinking, intercultural awareness, autonomy, active citizenship, teamwork, and problem-solving, among others. Based on this situation, it is relevant to know the effects of E+ on the VET field, namely questioning how international mobility instigates digitalization processes and supports emancipatory queries therein. As an education field that more directly connects to hard skills and an instrumental approach oriented to the labor market’s needs, a study was conducted to determine the effects of international mobility on developing digital literacy and soft skills in the VET field. In methodological terms, the study used semi-structured interviews with teaching and non-teaching staff from three VET schools who are strongly active in the E+ Program. The interviewees were three headmasters, four mobility project managers, and eight teachers experienced in international mobility. The data was subjected to qualitative content analysis using the NVivo 14 application. The results show that E+ international mobility promotes and facilitates the use of digital technologies as a pedagogical resource at VET schools and enhances and generates students’ soft skills. In conclusion, E+ mobility in the VET field supports adopting the program’s priorities by increasing the teachers’ knowledge and use of digital resources and amplifying and generating participants’ soft skills.Keywords: Erasmus international mobility, digital literacy, soft skills, vocational education and training
Procedia PDF Downloads 311079 The Conflict of Grammaticality and Meaningfulness of the Corrupt Words: A Cross-lingual Sociolinguistic Study
Authors: Jayashree Aanand, Gajjam
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The grammatical tradition in Sanskrit literature emphasizes the importance of the correct use of Sanskrit words or linguistic units (sādhu śabda) that brings the meritorious values, denying the attribution of the same religious merit to the incorrect use of Sanskrit words (asādhu śabda) or the vernacular or corrupt forms (apa-śabda or apabhraṁśa), even though they may help in communication. The current research, the culmination of the doctoral research on sentence definition, studies the difference among the comprehension of both correct and incorrect word forms in Sanskrit and Marathi languages in India. Based on the total of 19 experiments (both web-based and classroom-controlled) on approximately 900 Indian readers, it is found that while the incorrect forms in Sanskrit are comprehended with lesser accuracy than the correct word forms, no such difference can be seen for the Marathi language. It is interpreted that the incorrect word forms in the native language or in the language which is spoken daily (such as Marathi) will pose a lesser cognitive load as compared to the language that is not spoken on a daily basis but only used for reading (such as Sanskrit). The theoretical base for the research problem is as follows: among the three main schools of Language Science in ancient India, the Vaiyākaraṇas (Grammarians) hold that the corrupt word forms do have their own expressive power since they convey meaning, while as the Mimāṁsakas (the Exegesists) and the Naiyāyikas (the Logicians) believe that the corrupt forms can only convey the meaning indirectly, by recalling their association and similarity with the correct forms. The grammarians argue that the vernaculars that are born of the speaker’s inability to speak proper Sanskrit are regarded as degenerate versions or fallen forms of the ‘divine’ Sanskrit language and speakers who could not use proper Sanskrit or the standard language were considered as Śiṣṭa (‘elite’). The different ideas of different schools strictly adhere to their textual dispositions. For the last few years, sociolinguists have agreed that no variety of language is inherently better than any other; they are all the same as long as they serve the need of people that use them. Although the standard form of a language may offer the speakers some advantages, the non-standard variety is considered the most natural style of speaking. This is visible in the results. If the incorrect word forms incur the recall of the correct word forms in the reader as the theory suggests, it would have added one extra step in the process of sentential cognition leading to more cognitive load and less accuracy. This has not been the case for the Marathi language. Although speaking and listening to the vernaculars is the common practice and reading the vernacular is not, Marathi readers have readily and accurately comprehended the incorrect word forms in the sentences, as against the Sanskrit readers. The primary reason being Sanskrit is spoken and also read in the standard form only and the vernacular forms in Sanskrit are not found in the conversational data.Keywords: experimental sociolinguistics, grammaticality and meaningfulness, Marathi, Sanskrit
Procedia PDF Downloads 1251078 Influence of Packing Density of Layers Placed in Specific Order in Composite Nonwoven Structure for Improved Filtration Performance
Authors: Saiyed M Ishtiaque, Priyal Dixit
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Objectives: An approach is being suggested to design the filter media to maximize the filtration efficiency with minimum possible pressure drop of composite nonwoven by incorporating the layers of different packing densities induced by fibre of different deniers and punching parameters by using the concept of sequential punching technique in specific order in layered composite nonwoven structure. X-ray computed tomography technique is used to measure the packing density along the thickness of layered nonwoven structure composed by placing the layer of differently oriented fibres influenced by fibres of different deniers and punching parameters in various combinations to minimize the pressure drop at maximum possible filtration efficiency. Methodology Used: This work involves preparation of needle punched layered structure with batts 100g/m2 basis weight having fibre denier, punch density and needle penetration depth as variables to produce 300 g/m2 basis weight nonwoven composite. X-ray computed tomography technique is used to measure the packing density along the thickness of layered nonwoven structure composed by placing the layers of differently oriented fibres influenced by considered variables in various combinations. to minimize the pressure drop at maximum possible filtration efficiencyFor developing layered nonwoven fabrics, batts made of fibre of different deniers having 100g/m2 each basis weight were placed in various combinations. For second set of experiment, the composite nonwoven fabrics were prepared by using 3 denier circular cross section polyester fibre having 64 mm length on needle punched nonwoven machine by using the sequential punching technique to prepare the composite nonwoven fabrics. In this technique, three semi punched fabrics of 100 g/m2 each having either different punch densities or needle penetration depths were prepared for first phase of fabric preparation. These fabrics were later punched altogether to obtain the overall basis weight of 300 g/m2. The total punch density of the composite nonwoven fabric was kept at 200 punches/ cm2 with a needle penetration depth of 10 mm. The layered structures so formed were subcategorised into two groups- homogeneous layered structure in which all the three batts comprising the nonwoven fabric were made from same denier of fibre, punch density and needle penetration depth and were placed in different positions in respective fabric and heterogeneous layered structure in which batts were made from fibres of different deniers, punch densities and needle penetration depths and were placed in different positions. Contributions: The results concluded that reduction in pressure drop is not derived by the overall packing density of the layered nonwoven fabric rather sequencing of layers of specific packing density in layered structure decides the pressure drop. Accordingly, creation of inverse gradient of packing density in layered structure provided maximum filtration efficiency with least pressure drop. This study paves the way for the possibility of customising the composite nonwoven fabrics by the incorporation of differently oriented fibres in constituent layers induced by considered variablres for desired filtration properties.Keywords: filtration efficiency, layered nonwoven structure, packing density, pressure drop
Procedia PDF Downloads 741077 Biocultural Biographies and Molecular Memories: A Study of Neuroepigenetics and How Trauma Gets under the Skull
Authors: Elsher Lawson-Boyd
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In the wake of the Human Genome Project, the life sciences have undergone some fascinating changes. In particular, conventional beliefs relating to gene expression are being challenged by advances in postgenomic sciences, especially by the field of epigenetics. Epigenetics is the modification of gene expression without changes in the DNA sequence. In other words, epigenetics dictates that gene expression, the process by which the instructions in DNA are converted into products like proteins, is not solely controlled by DNA itself. Unlike gene-centric theories of heredity that characterized much of the 20th Century (where the genes were considered as having almost god-like power to create life), gene expression in epigenetics insists on environmental ‘signals’ or ‘exposures’, a point that radically deviates from gene-centric thinking. Science and Technology Studies (STS) scholars have shown that epigenetic research is having vast implications for the ways in which chronic, non-communicable diseases are conceptualized, treated, and governed. However, to the author’s knowledge, there have not yet been any in-depth sociological engagements with neuroepigenetics that examine how the field is affecting mental health and trauma discourse. In this paper, the author discusses preliminary findings from a doctoral ethnographic study on neuroepigenetics, trauma, and embodiment. Specifically, this study investigates the kinds of causal relations neuroepigenetic researchers are making between experiences of trauma and the development of mental illnesses like complex post-traumatic stress disorder (PTSD), both throughout a human’s lifetime and across generations. Using qualitative interviews and nonparticipant observation, the author focuses on two public-facing research centers based in Melbourne: Florey Institute of Neuroscience and Mental Health (FNMH), and Murdoch Children’s Research Institute (MCRI). Preliminary findings indicate that a great deal of ambiguity characterizes this infant field, particularly when animal-model experiments are employed and the results are translated into human frameworks. Nevertheless, researchers at the FNMH and MCRI strongly suggest that adverse and traumatic life events have a significant effect on gene expression, especially when experienced during early development. Furthermore, they predict that neuroepigenetic research will have substantial implications for the ways in which mental illnesses like complex PTSD are diagnosed and treated. These preliminary findings shed light on why medical and health sociologists have good reason to be chiming in, engaging with and de-black-boxing ideations emerging from postgenomic sciences, as they may indeed have significant effects for vulnerable populations not only in Australia but other developing countries in the Global South.Keywords: genetics, mental illness, neuroepigenetics, trauma
Procedia PDF Downloads 1241076 The Effects of Irregular Immigration Originating from Syria on Turkey's Security Issues
Authors: Muzaffer Topgul, Hasan Atac
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After the September 11 attacks, fight against terrorism has risen to higher levels in security concepts of the countries. The following reactions of some nation states have led to the formation of unstable areas in different parts of the World. Especially, in Iraq and Syria, the influences of radical groups have risen with the weakening of the central governments. Turkey (with the geographical proximity to the current crisis) has become a stop on the movement of people who were displaced because of terrorism. In the process, the policies of the Syrian regime resulted in a civil war which is still going on since 2011, and remain as an unresolved crisis. With the extension of the problem, changes occurred in foreign policies of the World Powers; moreover, the ongoing effects of the riots, conflicts of interests of foreign powers, conflicts in the region because of the activities of radical groups increased instability within the country. This case continues to affect the security of Turkey, particularly illegal immigration. It has exceeded the number of two million Syrians who took refuge in Turkey due to the civil war, while continuing uncertainty about the legal status of asylum seekers, besides the security problems of asylum-seekers themselves, there are problems in education, health and communication (language) as well. In this study, we will evaluate the term of immigration through the eyes of national and international law, place the disorganized and illegal immigration in security sphere, and define the elements/components of irregular migration within the changing security concept. Ultimately, this article will assess the effects of the Syrian refuges to Turkey’s short-term, mid-term, and long-term security in the light of the national and international data flows and solutions will be presented to the ongoing problem. While explaining the security problems the data and the donnees obtained from the nation and international corporations will be examined thorough the human security dimensions such as living conditions of the immigrants, the ratio of the genders, especially birth rate occasions, the education circumstances of the immigrant children, the effects of the illegal passing on the public order. In addition, the demographic change caused by the immigrants will be analyzed, the changing economical conditions where the immigrants mostly accumulate, and their participation in public life will be worked on and the economical obstacles sourcing due to irregular immigration will be clarified. By the entire datum gathered from the educational, cultural, social, economic, demographical extents, the regional factors affecting the migration and the role of irregular migration in Turkey’s future security will be revealed by implication to current knowledge sources.Keywords: displaced people, human security, irregular migration, refugees
Procedia PDF Downloads 3081075 Restructurasation of the Concept of Empire in the Social Consciousness of Modern Americans
Authors: Maxim Kravchenko
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The paper looks into the structure and contents of the concept of empire in the social consciousness of modern Americans. To construct the model of this socially and politically relevant concept we have conducted an experiment with respondents born and living in the USA. Empire is seen as a historic notion describing such entities as the British empire, the Russian empire, the Ottoman empire and others. It seems that the democratic regime adopted by most countries worldwide is incompatible with imperial status of a country. Yet there are countries which tend to dominate in the contemporary world and though they are not routinely referred to as empires, in many respects they are reminiscent of historical empires. Thus, the central hypothesis of the study is that the concept of empire is cultivated in some states through the intermediary of the mass media though it undergoes a certain transformation to meet the expectations of a democratic society. The transformation implies that certain components which were historically embedded in its structure are drawn to the margins of the hierarchical structure of the concept whereas other components tend to become central to the concept. This process can be referred to as restructuration of the concept of empire. To verify this hypothesis we have conducted a study which falls into two stages. First we looked into the definition of empire featured in dictionaries, the dominant conceptual components of empire are: importance, territory/lands, recognition, independence, authority/power, supreme/absolute. However, the analysis of 100 articles from American newspapers chosen at random revealed that authors rarely use the word «empire» in its basic meaning (7%). More often «empire» is used when speaking about countries, which no longer exist or when speaking about some corporations (like Apple or Google). At the second stage of the study we conducted an associative experiment with the citizens of the USA aged 19 to 45. The purpose of the experiment was to find out the dominant components of the concept of empire and to construct the model of the transformed concept. The experiment stipulated that respondents should give the first association, which crosses their mind, on reading such stimulus phrases as “strong military”, “strong economy” and others. The list of stimuli features various words and phrases associated with empire including the words representing the dominant components of the concept of empire. Then the associations provided by the respondents were classified into thematic clusters. For instance, the associations to the stimulus “strong military” were compartmentalized into three groups: 1) a country with strong military forces (North Korea, the USA, Russia, China); 2) negative impression of strong military (war, anarchy, conflict); 3) positive impression of strong military (peace, safety, responsibility). The experiment findings suggest that the concept of empire is currently undergoing a transformation which brings about a number of changes. Among them predominance of positively assessed components of the concept; emergence of two poles in the structure of the concept, that is “hero” vs. “enemy”; marginalization of any negatively assessed components.Keywords: associative experiment, conceptual components, empire, restructurasation of the concept
Procedia PDF Downloads 3121074 Reliability and Availability Analysis of Satellite Data Reception System using Reliability Modeling
Authors: Ch. Sridevi, S. P. Shailender Kumar, B. Gurudayal, A. Chalapathi Rao, K. Koteswara Rao, P. Srinivasulu
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System reliability and system availability evaluation plays a crucial role in ensuring the seamless operation of complex satellite data reception system with consistent performance for longer periods. This paper presents a novel approach for the same using a case study on one of the antenna systems at satellite data reception ground station in India. The methodology involves analyzing system's components, their failure rates, system's architecture, generation of logical reliability block diagram model and estimating the reliability of the system using the component level mean time between failures considering exponential distribution to derive a baseline estimate of the system's reliability. The model is then validated with collected system level field failure data from the operational satellite data reception systems that includes failure occurred, failure time, criticality of the failure and repair times by using statistical techniques like median rank, regression and Weibull analysis to extract meaningful insights regarding failure patterns and practical reliability of the system and to assess the accuracy of the developed reliability model. The study mainly focused on identification of critical units within the system, which are prone to failures and have a significant impact on overall performance and brought out a reliability model of the identified critical unit. This model takes into account the interdependencies among system components and their impact on overall system reliability and provides valuable insights into the performance of the system to understand the Improvement or degradation of the system over a period of time and will be the vital input to arrive at the optimized design for future development. It also provides a plug and play framework to understand the effect on performance of the system in case of any up gradations or new designs of the unit. It helps in effective planning and formulating contingency plans to address potential system failures, ensuring the continuity of operations. Furthermore, to instill confidence in system users, the duration for which the system can operate continuously with the desired level of 3 sigma reliability was estimated that turned out to be a vital input to maintenance plan. System availability and station availability was also assessed by considering scenarios of clash and non-clash to determine the overall system performance and potential bottlenecks. Overall, this paper establishes a comprehensive methodology for reliability and availability analysis of complex satellite data reception systems. The results derived from this approach facilitate effective planning contingency measures, and provide users with confidence in system performance and enables decision-makers to make informed choices about system maintenance, upgrades and replacements. It also aids in identifying critical units and assessing system availability in various scenarios and helps in minimizing downtime and optimizing resource allocation.Keywords: exponential distribution, reliability modeling, reliability block diagram, satellite data reception system, system availability, weibull analysis
Procedia PDF Downloads 831073 Migration, Labour Market, Capital Formation, and Social Security: A Study of Livelihoods of the Urban Poor in Two Different Cities of West Bengal in India
Authors: Arup Pramanik
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Most of the cities in the developing countries like Siliguri Municipal Corporation Area (SMCA) and Raiganj Municipality (RM) in West Bengal, India are changing typically in terms of demographic, economic and social relationship due to rapid pace of urbanization. The mushrooming growth of slums in SMCA and RM is the direct consequence of urbanization and migration due to regional imbalance, unbalanced growth process which is posing a serious threat to sustainable development of the country. Almost all the slums happen to be a breeding ground for poverty, negligence, and disease. Unpredictable growth of slums and poverty alleviation has now become a serious challenge to the global and national policy makers for the development of the slum dwellers. The ethical dimension of the poor in the cities like SMCA and RM stands on equal opportunities, inclusive and harmonious living without discrimination of any kind. But, the migrant slum dwellers in SMCA and RM do not possess high skill or education to enable them to find well paid employment in the formal sector and the surplus urban labour force is compelled to generate its own means of employment and survival in the informal sector. The survey data of the households has been analysedin terms of percentage, descriptive statistics which includes mean, Standard Deviation (SD), ANOVA (Mean Difference) etc., to analyse the socio economic variables of the households. The study shows that the migrant labour forces living in the slums are derived from the social security measures in both the municipal areas of SMCA and RM. The urban poor in the cities of SMCA and RM rely heavily on social capital amongst all the capital assets to help them ‘get by’ and ‘get ahead’. Despite, the slum dwellers in the study areas are vulnerable with respect to other determinants of capital assets. It is noteworthy that Indian plans of anti-poverty programmes was in a proper place even after the neo-liberal regime, where the basic idea behind the massive shift of various welfare and service oriented strategy to poverty reduction strategy for the benefit of the urban poor with the trickle down effects. But, the overall impact of the trickledown effect was unsatisfactory. The objective of the Paper is to assess the magnitude of migration and absorption in the urban labour market. Issues relating to capital formation, social security measures and the support of the Welfare State in order to meet 'Sustainable Development Goals'. This study also highlights the quality of life of urban poor migrants in terms of capital formation and livelihoods.Keywords: migration, slums, labour market, capital formation, social security
Procedia PDF Downloads 1171072 Two-wavelength High-energy Cr:LiCaAlF6 MOPA Laser System for Medical Multispectral Optoacoustic Tomography
Authors: Radik D. Aglyamov, Alexander K. Naumov, Alexey A. Shavelev, Oleg A. Morozov, Arsenij D. Shishkin, Yury P.Brodnikovsky, Alexander A.Karabutov, Alexander A. Oraevsky, Vadim V. Semashko
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The development of medical optoacoustic tomography with the using human blood as endogenic contrast agent is constrained by the lack of reliable, easy-to-use and inexpensive sources of high-power pulsed laser radiation in the spectral region of 750-900 nm [1-2]. Currently used titanium-sapphire, alexandrite lasers or optical parametric light oscillators do not provide the required and stable output characteristics, they are structurally complex, and their cost is up to half the price of diagnostic optoacoustic systems. Here we are developing the lasers based on Cr:LiCaAlF6 crystals which are free of abovementioned disadvantages and provides intensive ten’s ns-range tunable laser radiation at specific absorption bands of oxy- (~840 nm) and -deoxyhemoglobin (~757 nm) in the blood. Cr:LiCAF (с=3 at.%) crystals were grown in Kazan Federal University by the vertical directional crystallization (Bridgman technique) in graphite crucibles in a fluorinating atmosphere at argon overpressure (P=1500 hPa) [3]. The laser elements have cylinder shape with the diameter of 8 mm and 90 mm in length. The direction of the optical axis of the crystal was normal to the cylinder generatrix, which provides the π-polarized laser action correspondent to maximal stimulated emission cross-section. The flat working surfaces of the active elements were polished and parallel to each other with an error less than 10”. No any antireflection coating was applied. The Q-switched master oscillator-power amplifiers laser system (MOPA) with the dual-Xenon flashlamp pumping scheme in diffuse-reflectivity close-coupled head were realized. A specially designed laser cavity, consisting of dielectric highly reflective reflectors with a 2 m-curvature radius, a flat output mirror, a polarizer and Q-switch sell, makes it possible to operate sequentially in a circle (50 ns - laser one pulse after another) at wavelengths of 757 and 840 nm. The programmable pumping system from Tomowave Laser LLC (Russia) provided independent to each pulses (up to 250 J at 180 μs) pumping to equalize the laser radiation intensity at these wavelengths. The MOPA laser operates at 10 Hz pulse repetition rate with the output energy up to 210 mJ. Taking into account the limitations associated with physiological movements and other characteristics of patient tissues, the duration of laser pulses and their energy allows molecular and functional high-contrast imaging to depths of 5-6 cm with a spatial resolution of at least 1 mm. Highly likely the further comprehensive design of laser allows improving the output properties and realizing better spatial resolution of medical multispectral optoacoustic tomography systems.Keywords: medical optoacoustic, endogenic contrast agent, multiwavelength tunable pulse lasers, MOPA laser system
Procedia PDF Downloads 991071 Organ Donation after Medical Aid in Dying: A Critical Study of Clinical Processes and Legal Rules in Place
Authors: Louise Bernier
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Under some jurisdictions (including Canada), eligible patients can request and receive medical assistance in dying (MAiD) through lethal injections, inducing their cardiocirculatory death. Those same patients can also wish to donate their organs in the process. If they qualify as organ donors, a clinical and ethical rule called the 'dead donor rule' (DDR) requires the transplant teams to wait after cardiocirculatory death is confirmed, followed by a 'no touch' period (5 minutes in Canada) before they can proceed with organ removal. The medical procedures (lethal injections) as well as the delays associated with the DDR can damage organs (mostly thoracic organs) due to prolonged anoxia. Yet, strong scientific evidences demonstrate that operating differently and reconsidering the DDR would result in more organs of better quality available for transplant. This idea generates discomfort and resistance, but it is also worth considering, especially in a context of chronic shortage of available organs. One option that could be examined for MAiD’ patients who wish and can be organ donors would be to remove vital organs while patients are still alive (and under sedation). This would imply accepting that patient’s death would occur through organ donation instead of lethal injections required under MAiD’ legal rules. It would also mean that patients requesting MAiD and wishing to be organ donors could aspire to donate better quality organs, including their heart, an altruistic gesture that carries important symbolic value for many donors and their families. Following a patient centered approach, our hypothesis is that preventing vital organ donation from a living donor in all circumstance is neither perfectly coherent with how legal mentalities have evolved lately in the field of fundamental rights nor compatible with the clinical and ethical frameworks that shape the landscape in which those complex medical decisions unfold. Through a study of the legal, ethical, and clinical rules in place, both at the national and international levels, this analysis raises questions on the numerous inconsistencies associated with respecting the DDR with patients who have chosen to die through MAiD. We will begin with an assessment of the erosion of certain national legal frameworks that pertain to the sacred nature of the right to life which now also includes the right to choose how one wishes to die. We will then study recent innovative clinical protocols tested in different countries to help address acute organ shortage problems in creative ways. We will conclude this analysis with an ethical assessment of the situation, referring to principles such as justice, autonomy, altruism, beneficence, and non-malfeasance. This study will build a strong argument in favor of starting to allow vital organ donations from living donors in countries where MAiD is already permitted.Keywords: altruism, autonomy, dead donor rule, medical assistance in dying, non-malfeasance, organ donation
Procedia PDF Downloads 1761070 Stability Study of Hydrogel Based on Sodium Alginate/Poly (Vinyl Alcohol) with Aloe Vera Extract for Wound Dressing Application
Authors: Klaudia Pluta, Katarzyna Bialik-Wąs, Dagmara Malina, Mateusz Barczewski
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Hydrogel networks, due to their unique properties, are highly attractive materials for wound dressing. The three-dimensional structure of hydrogels provides tissues with optimal moisture, which supports the wound healing process. Moreover, a characteristic feature of hydrogels is their absorption properties which allow for the absorption of wound exudates. For the fabrication of biomedical hydrogels, a combination of natural polymers ensuring biocompatibility and synthetic ones that provide adequate mechanical strength are often used. Sodium alginate (SA) is one of the polymers widely used in wound dressing materials because it exhibits excellent biocompatibility and biodegradability. However, due to poor strength properties, often alginate-based hydrogel materials are enhanced by the addition of another polymer such as poly(vinyl alcohol) (PVA). This paper is concentrated on the preparation methods of sodium alginate/polyvinyl alcohol hydrogel system incorporating Aloe vera extract and glycerin for wound healing material with particular focus on the role of their composition on structure, thermal properties, and stability. Briefly, the hydrogel preparation is based on the chemical cross-linking method using poly(ethylene glycol) diacrylate (PEGDA, Mn = 700 g/mol) as a crosslinking agent and ammonium persulfate as an initiator. In vitro degradation tests of SA/PVA/AV hydrogels were carried out in Phosphate-Buffered Saline (pH – 7.4) as well as in distilled water. Hydrogel samples were firstly cut into half-gram pieces (in triplicate) and immersed in immersion fluid. Then, all specimens were incubated at 37°C and then the pH and conductivity values were measurements at time intervals. The post-incubation fluids were analyzed using SEC/GPC to check the content of oligomers. The separation was carried out at 35°C on a poly(hydroxy methacrylate) column (dimensions 300 x 8 mm). 0.1M NaCl solution, whose flow rate was 0.65 ml/min, was used as the mobile phase. Three injections with a volume of 50 µl were made for each sample. The thermogravimetric data of the prepared hydrogels were collected using a Netzsch TG 209 F1 Libra apparatus. The samples with masses of about 10 mg were weighed separately in Al2O3 crucibles and then were heated from 30°C to 900°C with a scanning rate of 10 °C∙min−1 under a nitrogen atmosphere. Based on the conducted research, a fast and simple method was developed to produce potential wound dressing material containing sodium alginate, poly(vinyl alcohol) and Aloe vera extract. As a result, transparent and flexible SA/PVA/AV hydrogels were obtained. The degradation experiments indicated that most of the samples immersed in PBS as well as in distilled water were not degraded throughout the whole incubation time.Keywords: hydrogels, wound dressings, sodium alginate, poly(vinyl alcohol)
Procedia PDF Downloads 1641069 Repair of Thermoplastic Composites for Structural Applications
Authors: Philippe Castaing, Thomas Jollivet
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As a result of their advantages, i.e. recyclability, weld-ability, environmental compatibility, long (continuous) fiber thermoplastic composites (LFTPC) are increasingly used in many industrial sectors (mainly automotive and aeronautic) for structural applications. Indeed, in the next ten years, the environmental rules will put the pressure on the use of new structural materials like composites. In aerospace, more than 50% of the damage are due to stress impact and 85% of damage are repaired on the fuselage (fuselage skin panels and around doors). With the arrival of airplanes mainly of composite materials, replacement of sections or panels seems difficult economically speaking and repair becomes essential. The objective of the present study is to propose a solution of repair to prevent the replacement the damaged part in thermoplastic composites in order to recover the initial mechanical properties. The classification of impact damage is not so not easy : talking about low energy impact (less than 35 J) can be totally wrong when high speed or weak thicknesses as well as thermoplastic resins are considered. Crash and perforation with higher energy create important damages and the structures are replaced without repairing, so we just consider here damages due to impacts at low energy that are as follows for laminates : − Transverse cracking; − Delamination; − Fiber rupture. At low energy, the damages are barely visible but can nevertheless reduce significantly the mechanical strength of the part due to resin cracks while few fiber rupture is observed. The patch repair solution remains the standard one but may lead to the rupture of fibers and consequently creates more damages. That is the reason why we investigate the repair of thermoplastic composites impacted at low energy. Indeed, thermoplastic resins are interesting as they absorb impact energy through plastic strain. The methodology is as follows: - impact tests at low energy on thermoplastic composites; - identification of the damage by micrographic observations; - evaluation of the harmfulness of the damage; - repair by reconsolidation according to the extent of the damage ; -validation of the repair by mechanical characterization (compression). In this study, the impacts tests are performed at various levels of energy on thermoplastic composites (PA/C, PEEK/C and PPS/C woven 50/50 and unidirectional) to determine the level of impact energy creating damages in the resin without fiber rupture. We identify the extent of the damage by US inspection and micrographic observations in the plane part thickness. The samples were in addition characterized in compression to evaluate the loss of mechanical properties. Then the strategy of repair consists in reconsolidating the damaged parts by thermoforming, and after reconsolidation the laminates are characterized in compression for validation. To conclude, the study demonstrates the feasibility of the repair for low energy impact on thermoplastic composites as the samples recover their properties. At a first step of the study, the “repair” is made by reconsolidation on a thermoforming press but we could imagine a process in situ to reconsolidate the damaged parts.Keywords: aerospace, automotive, composites, compression, damages, repair, structural applications, thermoplastic
Procedia PDF Downloads 3031068 Sustainable Harvesting, Conservation and Analysis of Genetic Diversity in Polygonatum Verticillatum Linn.
Authors: Anchal Rana
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Indian Himalayas with their diverse climatic conditions are home to many rare and endangered medicinal flora. One such species is Polygonatum verticillatum Linn., popularly known as King Solomon’s Seal or Solomon’s Seal. Its mention as an incredible medicinal herb comes from 5000 years ago in Indian Materia Medica as a component of Ashtavarga, a poly-herbal formulation comprising of eight herbs illustrated as world’s first ever revitalizing and rejuvenating nutraceutical food, which is now commercialised in the name ‘Chaywanprash’. It is an erect tall (60 to 120 cm) perennial herb with sessile, linear leaves and white pendulous flowers. The species grows well in an altitude range of 1600 to 3600 m amsl, and propagates mostly through rhizomes. The rhizomes are potential source for significant phytochemicals like flavonoids, phenolics, lectins, terpenoids, allantoin, diosgenin, β-Sitosterol and quinine. The presence of such phytochemicals makes the species an asset for antioxidant, cardiotonic, demulcent, diuretic, energizer, emollient, aphrodisiac, appetizer, glactagogue, etc. properties. Having profound concentrations of macro and micronutrients, species has fine prospects of being used as a diet supplement. However, due to unscientific and gregarious uprooting, it has been assigned a status of ‘vulnerable’ and ‘endangered’ in the Conservation Assessment and Management Plan (CAMP) process conducted by Foundation for Revitalisation of Local Health Traditions (FRLHT) during 2010, according to IUCN Red-List Criteria. Further, destructive harvesting, land use disturbances, heavy livestock grazing, climatic changes and habitat fragmentation have substantially contributed towards anomaly of the species. It, therefore, became imperative to conserve the diversity of the species and make judicious use in future research and commercial programme and schemes. A Gene Bank was therefore established at High Altitude Herbal Garden of the Forest Research Institute, Dehradun, India situated at Chakarata (30042’52.99’’N, 77051’36.77’’E, 2205 m amsl) consisting 149 accessions collected from thirty-one geographical locations spread over three Himalayan States of Jammu and Kashmir, Himachal Pradesh, and Uttarakhand. The present investigations purport towards sampling and collection of divergent germplasm followed by planting and cultivation techniques. The ultimate aim is thereby focussed on analysing genetic diversity of the species and capturing promising genotypes for carrying out further genetic improvement programme so to contribute towards sustainable development and healthcare.Keywords: Polygonatum verticillatum Linn., phytochemicals, genetic diversity, conservation, gene bank
Procedia PDF Downloads 1701067 Assessment of the Environmental Compliance at the Jurassic Production Facilities towards HSE MS Procedures and Kuwait Environment Public Authority Regulations
Authors: Fatemah Al-Baroud, Sudharani Shreenivas Kshatriya
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Kuwait Oil Company (KOC) is one of the companies for gas & oil production in Kuwait. The oil and gas industry is truly global; with operations conducted in every corner of the globe, the global community will rely heavily on oil and gas supplies. KOC has made many commitments to protect all due to KOC’s operations and operational releases. As per KOC’s strategy, the substantial increase in production activities will bring many challenges in managing various environmental hazards and stresses in the company. In order to handle those environmental challenges, the need of implementing effectively the health, safety, and environmental management system (HSEMS) is significant. And by implementing the HSEMS system properly, the environmental aspects of the activities, products, and services were identified, evaluated, and controlled in order to (i) Comply with local regulatory and other obligatory requirements; (ii) Comply with company policy and business requirements; and (iii) Reduce adverse environmental impact, including adverse impact to company reputation. Assessments for the Jurassic Production Facilities are being carried out as a part of the KOC HSEMS procedural requirement and monitoring the implementation of the relevant HSEMS procedures in the facilities. The assessments have been done by conducting series of theme audits using KOC’s audit protocol at JPFs. The objectives of the audits are to evaluate the compliance of the facilities towards the implementation of environmental procedures and the status of the KEPA requirement at all JPFs. The list of the facilities that were covered during the theme audit program are the following: (1) Jurassic Production Facility (JPF) – Sabriya (2) Jurassic Production Facility (JPF) – East Raudhatian (3) Jurassic Production Facility (JPF) – West Raudhatian (4)Early Production Facility (EPF 50). The auditing process comprehensively focuses on the application of KOC HSE MS procedures at JPFs and their ability to reduce the resultant negative impacts on the environment from the operations. Number of findings and observations were noted and highlighted in the audit reports and sent to all concerned controlling teams. The results of these audits indicated that the facilities, in general view, were in line with KOC HSE Procedures, and there were commitments in documenting all the HSE issues in the right records and plans. Further, implemented several control measures at JPFs that minimized/reduced the environmental impact, such as SRU were installed for sulphur recovery. Future scope and monitoring audit after a sufficient period of time will be carried out in conjunction with the controlling teams in order to verify the current status of the recommendations and evaluate the contractors' performance towards the required actions in preserving the environment.Keywords: assessment of the environmental compliance, environmental and social impact assessment, kuwait environment public authority regulations, health, safety and environment management procedures, jurassic production facilities
Procedia PDF Downloads 1841066 Comparison of Microstructure, Mechanical Properties and Residual Stresses in Laser and Electron Beam Welded Ti–5Al–2.5Sn Titanium Alloy
Authors: M. N. Baig, F. N. Khan, M. Junaid
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Titanium alloys are widely employed in aerospace, medical, chemical, and marine applications. These alloys offer many advantages such as low specific weight, high strength to weight ratio, excellent corrosion resistance, high melting point and good fatigue behavior. These attractive properties make titanium alloys very unique and therefore they require special attention in all areas of processing, especially welding. In this work, 1.6 mm thick sheets of Ti-5Al-2,5Sn, an alpha titanium (α-Ti) alloy, were welded using electron beam (EBW) and laser beam (LBW) welding processes to achieve a full penetration Bead-on Plate (BoP) configuration. The weldments were studied using polarized optical microscope, SEM, EDS and XRD. Microhardness distribution across the weld zone and smooth and notch tensile strengths of the weldments were also recorded. Residual stresses using Hole-drill Strain Measurement (HDSM) method and deformation patterns of the weldments were measured for the purpose of comparison of the two welding processes. Fusion zone widths of both EBW and LBW weldments were found to be approximately equivalent owing to fairly similar high power densities of both the processes. Relatively less oxide content and consequently high joint quality were achieved in EBW weldment as compared to LBW due to vacuum environment and absence of any shielding gas. However, an increase in heat-affected zone width and partial ά-martensitic transformation infusion zone of EBW weldment were observed because of lesser cooling rates associated with EBW as compared with LBW. The microstructure infusion zone of EBW weldment comprised both acicular α and ά martensite within the prior β grains whereas complete ά martensitic transformation was observed within the fusion zone of LBW weldment. Hardness of the fusion zone in EBW weldment was found to be lower than the fusion zone of LBW weldment due to the observed microstructural differences. Notch tensile specimen of LBW exhibited higher load capacity, ductility, and absorbed energy as compared with EBW specimen due to the presence of high strength ά martensitic phase. It was observed that the sheet deformation and deformation angle in EBW weldment were more than LBW weldment due to relatively more heat retention in EBW which led to more thermal strains and hence higher deformations and deformation angle. The lowest residual stresses were found in LBW weldments which were tensile in nature. This was owing to high power density and higher cooling rates associated with LBW process. EBW weldment exhibited highest compressive residual stresses due to which the service life of EBW weldment is expected to improve.Keywords: Laser and electron beam welding, Microstructure and mechanical properties, Residual stress and distortions, Titanium alloys
Procedia PDF Downloads 2251065 Optimization of Multi-Disciplinary Expertise and Resource for End-Stage Renal Failure (ESRF) Patient Care
Authors: Mohamed Naser Zainol, P. P. Angeline Song
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Over the years, the profile of end-stage renal patients placed under The National Kidney Foundation Singapore (NKFS) dialysis program has evolved, with a gradual incline in the number of patients with behavior-related issues. With these challenging profiles, social workers and counsellors are often expected to oversee behavior management, through referrals from its partnering colleagues. Due to the segregation of tasks usually found in many hospital-based multi-disciplinary settings, social workers’ and counsellors’ interventions are often seen as an endpoint, limiting other stakeholders’ involvement that could otherwise be potentially crucial in managing such patients. While patients’ contact in local hospitals often leads to eventual discharge, NKFS patients are mostly long term. It is interesting to note that these patients are regularly seen by a team of professionals that includes doctors, nurses, dietitians, exercise specialists in NKFS. The dynamism of relationships presents an opportunity for any of these professionals to take ownership of their potentials in leading interventions that can be helpful to patients. As such, it is important to have a framework that incorporates the strength of these professionals and also channels empowerment across the multi-disciplinary team in working towards wholistic patient care. This paper would like to suggest a new framework for NKFS’s multi-disciplinary team, where the group synergy and dynamics are used to encourage ownership and promote empowerment. The social worker and counsellor use group work skills and his/her knowledge of its members’ strengths, to generate constructive solutions that are centered towards patient’s growth. Using key ideas from Karl’s Tomm Interpersonal Communications, the Communication Management of Meaning and Motivational Interviewing, the social worker and counsellor through a series of guided meeting with other colleagues, facilitates the transmission of understanding, responsibility sharing and tapping on team resources for patient care. As a result, the patient can experience personal and concerted approach and begins to flow in a direction that is helpful for him. Using seven case studies of identified patients with behavioral issues, the social worker and counsellor apply this framework for a period of six months. Patient’s overall improvement through interventions as a result of this framework are recorded using the AB single case design, with baseline measured three months before referral. Interviews with patients and their families, as well as other colleagues that are not part of the multi-disciplinary team are solicited at mid and end points to gather their experiences about patient’s progress as a by-product of this framework. Expert interviews will be conducted on each member of the multi-disciplinary team to study their observations and experience in using this new framework. Hence, this exploratory framework hopes to identify the inherent usefulness in managing patients with behavior related issues. Moreover, it would provide indicators in improving aspects of the framework when applied to a larger population.Keywords: behavior management, end-stage renal failure, satellite dialysis, multi-disciplinary team
Procedia PDF Downloads 1451064 Real-Time Neuroimaging for Rehabilitation of Stroke Patients
Authors: Gerhard Gritsch, Ana Skupch, Manfred Hartmann, Wolfgang Frühwirt, Hannes Perko, Dieter Grossegger, Tilmann Kluge
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Rehabilitation of stroke patients is dominated by classical physiotherapy. Nowadays, a field of research is the application of neurofeedback techniques in order to help stroke patients to get rid of their motor impairments. Especially, if a certain limb is completely paralyzed, neurofeedback is often the last option to cure the patient. Certain exercises, like the imagination of the impaired motor function, have to be performed to stimulate the neuroplasticity of the brain, such that in the neighboring parts of the injured cortex the corresponding activity takes place. During the exercises, it is very important to keep the motivation of the patient at a high level. For this reason, the missing natural feedback due to a movement of the effected limb may be replaced by a synthetic feedback based on the motor-related brain function. To generate such a synthetic feedback a system is needed which measures, detects, localizes and visualizes the motor related µ-rhythm. Fast therapeutic success can only be achieved if the feedback features high specificity, comes in real-time and without large delay. We describe such an approach that offers a 3D visualization of µ-rhythms in real time with a delay of 500ms. This is accomplished by combining smart EEG preprocessing in the frequency domain with source localization techniques. The algorithm first selects the EEG channel featuring the most prominent rhythm in the alpha frequency band from a so-called motor channel set (C4, CZ, C3; CP6, CP4, CP2, CP1, CP3, CP5). If the amplitude in the alpha frequency band of this certain electrode exceeds a threshold, a µ-rhythm is detected. To prevent detection of a mixture of posterior alpha activity and µ-activity, the amplitudes in the alpha band outside the motor channel set are not allowed to be in the same range as the main channel. The EEG signal of the main channel is used as template for calculating the spatial distribution of the µ - rhythm over all electrodes. This spatial distribution is the input for a inverse method which provides the 3D distribution of the µ - activity within the brain which is visualized in 3D as color coded activity map. This approach mitigates the influence of lid artifacts on the localization performance. The first results of several healthy subjects show that the system is capable of detecting and localizing the rarely appearing µ-rhythm. In most cases the results match with findings from visual EEG analysis. Frequent eye-lid artifacts have no influence on the system performance. Furthermore, the system will be able to run in real-time. Due to the design of the frequency transformation the processing delay is 500ms. First results are promising and we plan to extend the test data set to further evaluate the performance of the system. The relevance of the system with respect to the therapy of stroke patients has to be shown in studies with real patients after CE certification of the system. This work was performed within the project ‘LiveSolo’ funded by the Austrian Research Promotion Agency (FFG) (project number: 853263).Keywords: real-time EEG neuroimaging, neurofeedback, stroke, EEG–signal processing, rehabilitation
Procedia PDF Downloads 3851063 Sensitivity Improvement of Optical Ring Resonator for Strain Analysis with the Direction of Strain Recognition Possibility
Authors: Tayebeh Sahraeibelverdi, Ahmad Shirazi Hadi Veladi, Mazdak Radmalekshah
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Optical sensors became attractive due to preciseness, low power consumption, and intrinsic electromagnetic interference-free characteristic. Among the waveguide optical sensors, cavity-based ones attended for the high Q-factor. Micro ring resonators as a potential platform have been investigated for various applications as biosensors to pressure sensors thanks to their sensitive ring structure responding to any small change in the refractive index. Furthermore, these small micron size structures can come in an array, bringing the opportunity to have any of the resonance in a specific wavelength and be addressed in this way. Another exciting application is applying a strain to the ring and making them an optical strain gauge where the traditional ones are based on the piezoelectric material. Making them in arrays needs electrical wiring and about fifty times bigger in size. Any physical element that impacts the waveguide cross-section, Waveguide elastic-optic property change, or ring circumference can play a role. In comparison, ring size change has a larger effect than others. Here an engineered ring structure is investigated to study the strain effect on the ring resonance wavelength shift and its potential for more sensitive strain devices. At the same time, these devices can measure any strain by mounting on the surface of interest. The idea is to change the" O" shape ring to a "C" shape ring with a small opening starting from 2π/360 or one degree. We used the Mode solution of Lumbrical software to investigate the effect of changing the ring's opening and the shift induced by applied strain. The designed ring radius is a three Micron silicon on isolator ring which can be fabricated by standard complementary metal-oxide-semiconductor (CMOS) micromachining. The measured wavelength shifts from1-degree opening of the ring to a 6-degree opening have been investigated. Opening the ring for 1-degree affects the ring's quality factor from 3000 to 300, showing an order of magnitude Q-factor reduction. Assuming a strain making the ring-opening from 1 degree to 6 degrees, our simulation results showing negligible Q-factor reduction from 300 to 280. A ring resonator quality factor can reach up to 108 where an order of magnitude reduction is negligible. The resonance wavelength shift showed a blue shift and was obtained to be 1581, 1579,1578,1575nm for 1-, 2-, 4- and 6-degree ring-opening, respectively. This design can find the direction of the strain-induced by applying the opening on different parts of the ring. Moreover, by addressing the specified wavelength, we can precisely find the direction. We can open a significant opportunity to find cracks and any surface mechanical property very specifically and precisely. This idea can be implemented on polymer ring resonators while they can come with a flexible substrate and can be very sensitive to any strain making the two ends of the ring in the slit part come closer or further.Keywords: optical ring resonator, strain gauge, strain sensor, surface mechanical property analysis
Procedia PDF Downloads 1251062 Loading by Number Strategy for Commercial Vehicles
Authors: Ramalan Musa Yerima
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The paper titled “loading by number” explained a strategy developed recently by Zonal Commanding Officer of the Federal Road Safety Corps of Nigeria, covering Sokoto, Kebbi and Zamfara States of Northern Nigeria. The strategy is aimed at reducing competition, which will invariably leads to the reduction in speed, reduction in dangerous driving, reduction in crash rate, reduction in injuries, reduction in property damages and reduction in death through road traffic crashes (RTC). This research paper presents a study focused on enhancing the safety of commercial vehicles. The background of this study highlights the alarming statistics related to commercial vehicle crashes in Nigeria with focus on Sokoto, Kebbi and Zamfara States, which often result in significant damage to property, loss of lives, and economic costs. The significance and aims is to investigate and propose effective strategy to enhance the safety of commercial vehicles. The study recognizes the pressing need for heightened safety measures in commercial transportation, as it impacts not only the well-being of drivers and passengers but also the overall public safety. To achieve the objectives, an examination of accident data, including causes and contributing factors, was performed to identify critical areas for improvement. The major finding of the study reveals that when competition comes into play within the realm of commercial driving, it has detrimental effects on road safety and resource management. Commercial drivers are pushed to complete their routes quickly, deliver goods on time or they pushed themselves to arrive quickly for more passengers and new contracts. This competitive environment, fuelled by internal and external pressures such as tight deadlines, poverty and greed, often leads to sad endings. The study recommend that if a strategy called loading by number is integrated with other multiple safety measures such as driver training programs, regulatory enforcement, and infrastructure improvements, commercial vehicle safety can be significantly enhanced. "Loading by Number” approach is design to ensure that the sequence of departure of drivers from motor park ‘A’ would be communicated to motor park officials of park ‘B’, which would be considered sequentially when giving them returning passengers, regardless of the first to arrive. In conclusion, this paper underscores the significance of improving the safety measures of commercial vehicles, as they are often larger and heavier than other vehicles on the road. Whenever they are involved in accidents, the consequences can be more severe. Commercial vehicles are also frequently involved in long-haul or interstate transportation, which means they cover longer distances and spend more time on the road. This increased exposure to driving conditions increases the probability of accidents occurring. By implementing the suggested measures, policymakers, transportation authorities, and industry stakeholders can work collectively towards ensuring a safer commercial transportation system.Keywords: commercial, safety, strategy, transportation
Procedia PDF Downloads 601061 Cryotopic Macroporous Polymeric Matrices for Regenerative Medicine and Tissue Engineering Applications
Authors: Archana Sharma, Vijayashree Nayak, Ashok Kumar
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Three-dimensional matrices were fabricated from blend of natural-natural polymers like carrageenan-gelatin and synthetic -natural polymers such as PEG- gelatin (PEG of different molecular weights (2,000 and 6,000) using two different crosslinkers; glutaraldehyde and EDC-NHS by cryogelation technique. Blends represented a feasible approach to design 3-D scaffolds with controllable mechanical, physical and biochemical properties without compromising biocompatibility and biodegradability. These matrices possessed interconnected porous structure, good mechanical strength, biodegradable nature, constant swelling kinetics, ability to withstand high temperature and visco-elastic behavior. Hemocompatibility of cryogel matrices was determined by coagulation assays and hemolytic activity assay which demonstrated that these cryogels have negligible effects on coagulation time and have excellent blood compatibility. In vitro biocompatibility (cell-matrix interaction) inferred good cell adhesion, proliferation, and secretion of ECM on matrices. These matrices provide a microenvironment for the growth, proliferation, differentiation and secretion of ECM of different cell types such as IMR-32, C2C12, Cos-7, rat bone marrow derived MSCs and human bone marrow MSCs. Hoechst 33342 and PI staining also confirmed that the cells were uniformly distributed, adhered and proliferated properly on the cryogel matrix. An ideal scaffold used for tissue engineering application should allow the cells to adhere, proliferate and maintain their functionality. Neurotransmitter analysis has been done which indicated that IMR-32 cells adhered, proliferated and secreted neurotransmitters when they interacted with these matrices which showed restoration of their functionality. The cell-matrix interaction up to molecular level was also evaluated so to check genotoxicity and protein expression profile which indicated that these cryogel matrices are non-genotoxic and maintained biofunctionality of cells growing on these matrices. All these cryogels, when implanted subcutaneously in balb/c mice, showed no adverse systemic or local toxicity effects at implantation site. There was no significant increase in inflammatory cell count has otherwise been observed after scaffold implantation. These cryogels are supermacroporous and this porous structure allows cell infiltration and proliferation of host cells. This showed the integration and presence of infiltrated cells into the cryogel implants. Histological analysis confirmed that the implanted cryogels do not have any adverse effect in spite of host immune system recognition at the site of implantation, on its surrounding tissues and other vital host organs. In vivo biocompatibility study after in vitro biocompatibility analysis has also concluded that these synthesized cryogels act as important biological substitutes, more adaptable and appropriate for transplantation. Thus, these cryogels showed their potential for soft tissue engineering applications.Keywords: cryogelation, hemocompatibility, in vitro biocompatibility, in vivo biocompatibility, soft tissue engineering applications
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