Search results for: interest rate and trade openness
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 12442

Search results for: interest rate and trade openness

10642 Simulation-Based Parametric Study for the Hybrid Superplastic Forming of AZ31

Authors: Fatima Ghassan Al-Abtah, Naser Al-Huniti, Elsadig Mahdi

Abstract:

As the lightest constructional metal on earth, magnesium alloys offer excellent potential for weight reduction in the transportation industry, and it was observed that some magnesium alloys exhibit superior ductility and superplastic behavior at high temperatures. The main limitation of the superplastic forming (SPF) includes the low production rate since it needs a long forming time for each part. Through this study, an SPF process that starts with a mechanical pre-forming stage is developed to promote formability and reduce forming time. A two-dimensional finite element model is used to simulate the process. The forming process consists of two steps. At the pre-forming step (deep drawing), the sheet is drawn into the die to a preselected level, using a mechanical punch, and at the second step (SPF) a pressurized gas is applied at a controlled rate. It is shown that a significant reduction in forming time and improved final thickness uniformity can be achieved when the hybrid forming technique is used, where the process achieved a fully formed part at 400°C. Investigation for the impact of different forming process parameters achieved by comparing forming time and the distribution of final thickness that were obtained from the simulation analysis. Maximum thinning decreased from over 67% to less than 55% and forming time significantly decreased by more than 6 minutes, and the required gas pressure profile was predicted for optimum forming process parameters based on the 0.001/sec target constant strain rate within the sheet.

Keywords: magnesium, plasticity, superplastic forming, finite element analysis

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10641 Democratic Action as Insurgency: On Claude Lefort's Concept of the Political Regime

Authors: Lorenzo Buti

Abstract:

This paper investigates the nature of democratic action through a critical reading of Claude Lefort’s notion of the democratic ‘regime’. Lefort provides one of the most innovative accounts of the essential features of a democratic regime. According to him, democracy is a political regime that acknowledges the indeterminacy of a society and stages it as a contestation between competing political actors. As such, democracy provides the symbolic markers of society’s openness towards the future. However, despite their democratic features, the recent decades in late capitalist societies attest to a sense of the future becoming fixed and predetermined. This suggests that Lefort’s conception of democracy harbours a misunderstanding of the character and experience of democratic action. This paper examines this underlying tension in Lefort’s work. It claims that Lefort underestimates how a democratic regime, next to its symbolic function, also takes a materially constituted form with its particular dynamics of power relations. Lefort’s systematic dismissal of this material dimension for democratic action can lead to the contemporary paradoxical situation where democracy’s symbolic markers are upheld (free elections, public debate, dynamic between government and opposition in parliament,…) but the room for political decision-making is constrained due to a myriad of material constraints (e.g., market pressures, institutional inertias). The paper draws out the implications for the notion of democratic action. Contra Lefort, it argues that democratic action necessarily targets the material conditions that impede the capacity for decision-making on the basis of equality and liberty. This analysis shapes our understanding of democratic action in two ways. First, democratic action takes an asymmetrical, insurgent form, as a contestation of material power relations from below. Second, it reveals an ambivalent position vis-à-vis the political regime: democratic action is symbolically made possible by the democratic dispositive, but it contests the constituted form that the democratic regime takes.

Keywords: Claude Lefort, democratic action, material constitution, political regime

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10640 The Comparison of Personality Background of Volunteer and Non-Volunteer Subjects

Authors: Laszlo Dorner

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Background: In the last few decades there has been a significant discussion within the researchers of prosocial behavior about to what extent personality characteristics matter in determining the quality and frequency of helping behaviors. Of these community activities the most important is formal volunteering which mainly realises in civil services and organizations. Recently many researches have been showed up regarding the personality factors and motivations behind volunteering). Most of these researches found strong correlation between Agreeableness and Extraversion as global traits and the time spent on volunteering and its frequency as well. Aims of research: In this research we investigate the relation between formal volunteer activities and global traits in a Hungarian volunteer sample. We hypothetise that the results appeared in the previous researches show the same pattern in Hungary as well: volunteering would be related to Agreeableness and Extraversion. We also assume that the time spent on volunteering is related to these traits, since these traits would serve as an indicator of long-term volunteering. Methods: We applied the Hungarian adaptation of Big Five Questionnaire created by Caprara, Barbaranelli és Borgogni. This self-reported questionnaire contains 132 items, and explore 5 main traits examining the person’s most important emotional and motivational features regarding its personality. This research took into account the most important socio-economical factors (age, gender, religiosity, income) which can determine volunteer activities per se. The data is evaluated by SPSS 19.0 Statistical Software. Sample: 92 volunteer (formal, mainly the volunteers of Hungarian Red Cross and Hospice Organizations)and 92 non volunteer person, with matched subsamples by the factors of age, gender and qualification. Results: The volunteer subsample shows higher values of Energy and significantly higher values of Agreeableness and Openness, however, regarding Conscientiousness and Emotional Stability the differences are not significant between the volunteer and non-volunteer subsamples.

Keywords: Big Five, comparative analysis, global traits, volunteering

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10639 In vivo Genotoxicity Testing of Sesbania Grandiflora (Katuray) Flower Methanolic Extract

Authors: Levylee Bautista, Dawn Grace Santos, Aishwarya Veluchamy, Jesusa Santos, Ghafoor, Jr. I Haque, Rodolfo Rafael

Abstract:

The booming interest in using natural compounds as an alternative to conventional medications has paved way to focus the attention on plants that provide rich sources of bioactive phytochemicals. For regulatory purposes, evaluation of the genotoxic effects of such alternatives is therefore empirical as part of the plant’s hazard assessment. Sesbania grandiflora is among the plants used as a traditional remedy in folk medicine and a subject of research for its medicinal benefits. This study aimed to evaluate the genotoxic potential induced by S. grandiflora flower methanol extract (SGFME) in terms of the frequency of micronucleus (MN) in polychromatic erythrocyte (PCE) (MNPCE) and PCE ratio employing the micronucleus assay. The frequency of MN was examined in bone marrow cells (BMCs) obtained from male Swiss albino mice exposed in vivo to four different concentrations (11.25, 22.5, 40, and 90 mg/kg) of SGFME and MMC (70 mg/kg; positive control) and sacrificed 24 hours post-intraperitoneal injection. Results showed a significant (p < 0.01) rate of MNPCEs for 11.25 and 22.5 tested concentrations of SGFME and is comparable with the MMC-treated mice. Although PCE ratio values in all doses of SGFME-treated mice were over 0.20, it is worth noting that 40 and 90 tested concentrations of SGFME-treated mice exhibited the lowest value, i.e., 0.22 and 0.28, respectively. The present study has demonstrated that S. grandiflora possesses genotoxic potential for murine BMCs. Such activity could be ascribed from the bioactive compounds present in S. grandiflora that require further isolation and characterization of the active molecules. Likewise, findings of this study warrant a caution of the use of S. grandiflora insomuch as further investigations do not demonstrate their safety.

Keywords: genotoxicity, micronucleus, phytochemicals, Sesbania grandiflora

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10638 An Automatic Feature Extraction Technique for 2D Punch Shapes

Authors: Awais Ahmad Khan, Emad Abouel Nasr, H. M. A. Hussein, Abdulrahman Al-Ahmari

Abstract:

Sheet-metal parts have been widely applied in electronics, communication and mechanical industries in recent decades; but the advancement in sheet-metal part design and manufacturing is still behind in comparison with the increasing importance of sheet-metal parts in modern industry. This paper presents a methodology for automatic extraction of some common 2D internal sheet metal features. The features used in this study are taken from Unipunch ™ catalogue. The extraction process starts with the data extraction from STEP file using an object oriented approach and with the application of suitable algorithms and rules, all features contained in the catalogue are automatically extracted. Since the extracted features include geometry and engineering information, they will be effective for downstream application such as feature rebuilding and process planning.

Keywords: feature extraction, internal features, punch shapes, sheet metal

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10637 Feature Based Unsupervised Intrusion Detection

Authors: Deeman Yousif Mahmood, Mohammed Abdullah Hussein

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The goal of a network-based intrusion detection system is to classify activities of network traffics into two major categories: normal and attack (intrusive) activities. Nowadays, data mining and machine learning plays an important role in many sciences; including intrusion detection system (IDS) using both supervised and unsupervised techniques. However, one of the essential steps of data mining is feature selection that helps in improving the efficiency, performance and prediction rate of proposed approach. This paper applies unsupervised K-means clustering algorithm with information gain (IG) for feature selection and reduction to build a network intrusion detection system. For our experimental analysis, we have used the new NSL-KDD dataset, which is a modified dataset for KDDCup 1999 intrusion detection benchmark dataset. With a split of 60.0% for the training set and the remainder for the testing set, a 2 class classifications have been implemented (Normal, Attack). Weka framework which is a java based open source software consists of a collection of machine learning algorithms for data mining tasks has been used in the testing process. The experimental results show that the proposed approach is very accurate with low false positive rate and high true positive rate and it takes less learning time in comparison with using the full features of the dataset with the same algorithm.

Keywords: information gain (IG), intrusion detection system (IDS), k-means clustering, Weka

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10636 Biopolitical Border Imagery during the European Migrant Crisis: A Comparative Discourse Analysis between Mediterranean Europe and the Balkans

Authors: Mira Kaneva

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The ongoing migration crisis polemic opens up the debate to the ambivalent essence of borders due to both the legality and legitimacy of the displacement of vast masses of people across the European continent. In neoliberal terms, migration is seen as an economic opportunity, or, on the opposite, as a social disparity; in realist terms, it is regarded as a security threat that calls for mobilization; from a critical standpoint, it is a matter of discourse on democratic governance. This paper sets the objective of analyzing borders through the Foucauldian prism of biopolitics. It aims at defining the specifics of the management of the human body by producing both the irregular migrant as a subject (but prevalently as an object in the discourse) and the political subjectivity by exercising state power in repressive practices, including hate speech. The study relies on the conceptual framework of Bigo, Agamben, Huysmans, among others, and applies the methodology of qualitative comparative analysis between the cases of borders (fences, enclaves, camps and other forms of abnormal spatiality) in Italy, Spain, Greece, the Republic of Macedonia, Serbia and Bulgaria. The paper thus tries to throw light on these cross- and intra-regional contexts that share certain similarities and differences. It tries to argue that the governmentality of the masses of refugees and economic immigrants through the speech acts of their exclusion leads to a temporary populist backlash; a tentative finding is that the status-quo in terms of social and economic measures remains relatively balanced, whereas, values such as freedom, openness, and tolerance are consecutively marginalized.

Keywords: Balkans, biopolitical borders, cross- and intra-regional discourse analysis, irregular migration, Mediterranean Europe, securitization vs. humanitarianism

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10635 How Tattoos and Brands Impact the Recovery of Sex Trafficking Victim: An Exploratory Study of Sex Trafficking Survivors.

Authors: Jeremy Berry, Shannon Rodrigue, Caroline Norris

Abstract:

This study explores the impact of tattoos and/or brands on the recovery of sex trafficking survivors. Many victims of sex trafficking are forced or coerced to take markings of ownership while in the sex trafficking trade in the form of painful tattoos or brands. As a result, victims who are rescued and in recovery often must live with permanent reminders of their traumatic experiences or are left to resort to expensive cosmetic or cover-up jobs, which for many are out of reach. As is often true of domestic violence victims who are left with scars from their abusers, the impact of these permanent markers can delay the healing process and contribute to post-traumatic stress. This study tells the story from the perspectives of the survivors of sex trafficking, how these specific permanent reminders impacted their healing. The study employs a thematic analysis of interviews with sex trafficking victims via focus group interviews.

Keywords: sex trafficking, tattoos, trauma, healing

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10634 Wharton's Jelly-Derived Mesenchymal Stem Cells Modulate Heart Rate Variability and Improve Baroreflex Sensitivity in Septic Rats

Authors: Cóndor C. José, Rodrigues E. Camila, Noronha L. Irene, Dos Santos Fernando, Irigoyen M. Claudia, Andrade Lúcia

Abstract:

Sepsis induces alterations in hemodynamics and autonomic nervous system (ASN). The autonomic activity can be calculated by measuring heart rate variability (HRV) that represents the complex interplay between ASN and cardiac pacemaker cells. Wharton’s jelly mesenchymal stem cells (WJ-MSCs) are known to express genes and secreted factors involved in neuroprotective and immunological effects, also to improve the survival in experimental septic animals. We hypothesized, that WJ-MSCs present an important role in the autonomic activity and in the hemodynamic effects in a cecal ligation and puncture (CLP) model of sepsis. Methods: We used flow cytometry to evaluate WJ-MSCs phenotypes. We divided Wistar rats into groups: sham (shamoperated); CLP; and CLP+MSC (106 WJ-MSCs, i.p., 6 h after CLP). At 24 h post-CLP, we recorded the systolic arterial pressure (SAP) and heart rate (HR) over 20 min. The spectral analysis of HR and SAP; also the spontaneous baroreflex sensitivity (measure by bradycardic and tachycardic responses) were evaluated after recording. The one-way ANOVA and the post hoc Student– Newman– Keuls tests (P< 0.05) were used to data comparison Results: WJ-MSCs were negative for CD3, CD34, CD45 and HLA-DR, whereas they were positive for CD73, CD90 and CD105. The CLP group showed a reduction in variance of overall variability and in high-frequency power of HR (heart parasympathetic activity); furthermore, there is a low-frequency reduction of SAP (blood vessels sympathetic activity). The treatment with WJ-MSCs improved the autonomic activity by increasing the high and lowfrequency power; and restore the baroreflex sensitive. Conclusions: WJ-MSCs attenuate the impairment of autonomic control of the heart and vessels and might therefore play a protective role in sepsis. (Supported by FAPESP).

Keywords: baroreflex response, heart rate variability, sepsis, wharton’s jelly-derived mesenchymal stem cells

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10633 The Phenomenon of Nutrition as a 'Trading Zone' Approach in the Paradigm Shift between Humoral Theory and Modern Medicine

Authors: Dilay Merve Temur

Abstract:

How knowledge is produced and how scientific knowledge progress are questions that science philosophers have investigated for centuries. When the scientific and technological developments reached the 20th century, Kuhn proposed a completely new view among all the approaches. In this article, firstly, Kuhn's theory is represented. Secondly, the criticisms of Kuhn's theory directed to him are examined, and Galison's proposal for the trade area term of the incommensurability thesis is shared. The interaction of Humoral Theory with nutrition has been illustrated extensively, and the transition to modern medicine has been described historically by including scientific and technological developments in the field of medicine. This paper will seek to see how the concept of nutrition is positioned as a trading zone within the medicine paradigm, which has experienced a revolution within the framework of the paradigm concept introduced by Kuhn.

Keywords: food studies, incommensurability, nutrition and dietetics, trading zone

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10632 Impact of Different Fuel Inlet Diameters onto the NOx Emissions in a Hydrogen Combustor

Authors: Annapurna Basavaraju, Arianna Mastrodonato, Franz Heitmeir

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The Advisory Council for Aeronautics Research in Europe (ACARE) is creating awareness for the overall reduction of NOx emissions by 80% in its vision 2020. Hence this promotes the researchers to work on novel technologies, one such technology is the use of alternative fuels. Among these fuels hydrogen is of interest due to its one and only significant pollutant NOx. The influence of NOx formation due to hydrogen combustion depends on various parameters such as air pressure, inlet air temperature, air to fuel jet momentum ratio etc. Appropriately, this research is motivated to investigate the impact of the air to fuel jet momentum ratio onto the NOx formation in a hydrogen combustion chamber for aircraft engines. The air to jet fuel momentum is defined as the ratio of impulse/momentum of air with respect to the momentum of fuel. The experiments were performed in an existing combustion chamber that has been previously tested for methane. Premix of the reactants has not been considered due to the high reactivity of the hydrogen and high risk of a flashback. In order to create a less rich zone of reaction at the burner and to decrease the emissions, a forced internal recirculation flow has been achieved by integrating a plate similar to honeycomb structure, suitable to the geometry of the liner. The liner has been provided with an external cooling system to avoid the increase of local temperatures and in turn the reaction rate of the NOx formation. The injected air has been preheated to aim at so called flameless combustion. The air to fuel jet momentum ratio has been inspected by changing the area of fuel inlets and keeping the number of fuel inlets constant in order to alter the fuel jet momentum, thus maintaining the homogeneity of the flow. Within this analysis, promising results for a flameless combustion have been achieved. For a constant number of fuel inlets, it was seen that the reduction of the fuel inlet diameter resulted in decrease of air to fuel jet momentum ratio in turn lowering the NOx emissions.

Keywords: combustion chamber, hydrogen, jet momentum, NOx emission

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10631 Analysis of Delamination in Drilling of Composite Materials

Authors: Navid Zarif Karimi, Hossein Heidary, Giangiacomo Minak, Mehdi Ahmadi

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In this paper analytical model based on the mechanics of oblique cutting, linear elastic fracture mechanics (LEFM) and bending plate theory has been presented to determine the critical feed rate causing delamination in drilling of composite materials. Most of the models in this area used LEFM and bending plate theory; hence, they can only determine the critical thrust force which is an incorporable parameter. In this model by adding cutting oblique mechanics to previous models, critical feed rate has been determined. Also instead of simplification in loading condition, actual thrust force induced by chisel edge and cutting lips on composite plate is modeled.

Keywords: composite material, delamination, drilling, thrust force

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10630 The Impact of Large-Scale Wind Energy Development on Islands’ Interconnection to the Mainland System

Authors: Marina Kapsali, John S. Anagnostopoulos

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Greek islands’ interconnection (IC) with larger power systems, such as the mainland grid, is a crucial issue that has attracted a lot of interest; however, the recent economic recession that the country undergoes together with the highly capital intensive nature of this kind of projects have stalled or sifted the development of many of those on a more long-term basis. On the other hand, most of Greek islands are still heavily dependent on the lengthy and costly supply chain of oil imports whilst the majority of them exhibit excellent potential for wind energy (WE) applications. In this respect, the main purpose of the present work is to investigate −through a parametric study which varies both in wind farm (WF) and submarine IC capacities− the impact of large-scale WE development on the IC of the third in size island of Greece (Lesbos) with the mainland system. The energy and economic performance of the system is simulated over a 25-year evaluation period assuming two possible scenarios, i.e. S(a): without the contribution of the local Thermal Power Plant (TPP) and S(b): the TPP is maintained to ensure electrification of the island. The economic feasibility of the two options is investigated in terms of determining their Levelized Cost of Energy (LCOE) including also a sensitivity analysis on the worst/reference/best Cases. According to the results, Lesbos island IC presents considerable economic interest for covering part of island’s future electrification needs with WE having a vital role in this challenging venture.

Keywords: electricity generation cost, levelized cost of energy, mainland grid, wind energy rejection

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10629 Comparison of Various Classification Techniques Using WEKA for Colon Cancer Detection

Authors: Beema Akbar, Varun P. Gopi, V. Suresh Babu

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Colon cancer causes the deaths of about half a million people every year. The common method of its detection is histopathological tissue analysis, it leads to tiredness and workload to the pathologist. A novel method is proposed that combines both structural and statistical pattern recognition used for the detection of colon cancer. This paper presents a comparison among the different classifiers such as Multilayer Perception (MLP), Sequential Minimal Optimization (SMO), Bayesian Logistic Regression (BLR) and k-star by using classification accuracy and error rate based on the percentage split method. The result shows that the best algorithm in WEKA is MLP classifier with an accuracy of 83.333% and kappa statistics is 0.625. The MLP classifier which has a lower error rate, will be preferred as more powerful classification capability.

Keywords: colon cancer, histopathological image, structural and statistical pattern recognition, multilayer perception

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10628 Analysis of Minimizing Investment Risks in Power and Energy Business Development by Combining Total Quality Management and International Financing Institutions Project Management Tools

Authors: M. Radunovic

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Region of Southeastern Europe has a substantial energy resource potential and is witnessing an increasing rate of power and energy project investments. This comes as a result of countries harmonizing their legal framework and market regulations to conform the ones of European Union, enabling direct private investments. Funding in the power and energy market in this region originates from various resources and investment entities, including commercial and institutional ones. Risk anticipation and assessment is crucial to project success, especially given the long exploitation period of project in power and energy domain, as well as the wide range of stakeholders involved. This paper analyzes the possibility of combined application of tools used in total quality management and international financing institutions for project planning, execution and evaluation, with the goal of anticipating, assessing and minimizing the risks that might occur in the development and execution phase of a power and energy project in the market of southeastern Europe. History of successful project management and investments both in the industry and institutional sector provides sufficient experience, guidance and internationally adopted tools to provide proper project assessment for investments in power and energy. Business environment of southeastern Europe provides immense potential for developing power and engineering projects of various magnitudes, depending on stakeholders’ interest. Diversification on investment sources provides assurance that there is interest and commitment to invest in this market. Global economic and political developments will be intensifying the pace of investments in the upcoming period. The proposed approach accounts for key parameters that contribute to the sustainability and profitability of a project which include technological, educational, social and economic gaps between the southeastern European region and western Europe, market trends in equipment design and production on a global level, environment friendly approach to renewable energy sources as well as conventional power generation systems, and finally the effect of the One Belt One Road Initiative led by People’s Republic of China to the power and energy market of this region in the upcoming period on a long term scale. Analysis will outline the key benefits of the approach as well as the accompanying constraints. Parallel to this it will provide an overview of dominant threats and opportunities in present and future business environment and their influence to the proposed application. Through concrete examples, full potential of this approach will be presented along with necessary improvements that need to be implemented. Number of power and engineering projects being developed in southeastern Europe will be increasing in the upcoming period. Proper risk analysis will lead to minimizing project failures. The proposed successful combination of reliable project planning tools from different investment areas can prove to be beneficial in the future power and engineering investments, and guarantee their sustainability and profitability.

Keywords: capital investments, lean six sigma, logical framework approach, logical framework matrix, one belt one road initiative, project management tools, quality function deployment, Southeastern Europe, total quality management

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10627 Formulation and Evaluation of Solid Dispersion of an Anti-Epileptic Drug Carbamazepine

Authors: Sharmin Akhter, M. Salahuddin, Sukalyan Kumar Kundu, Mohammad Fahim Kadir

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Relatively insoluble candidate drug like carbamazepine (CBZ) often exhibit incomplete or erratic absorption; and hence wide consideration is given to improve aqueous solubility of such compound. Solid dispersions were formulated with an aim of improving aqueous solubility, oral bioavailability and the rate of dissolution of Carbamazepine using different hydrophyllic polymer like Polyethylene Glycol (PEG) 6000, Polyethylene Glycol (PEG) 4000, kollidon 30, HPMC 6 cps, poloxamer 407 and povidone k 30. Solid dispersions were prepared with different drug to polymer weight ratio by the solvent evaporation method where methanol was used as solvent. Drug-polymer physical mixtures were also prepared to compare the rate of dissolution. Effects of different polymer were studied for solid dispersion formulation as well as physical mixtures. These formulations were characterized in the solid state by Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM). Solid state characterization indicated CBZ was present as fine particles and entrapped in carrier matrix of PEG 6000 and PVP K30 solid dispersions. Fourier Transform Infrared (FTIR) spectroscopic studies showed the stability of CBZ and absence of well-defined drug-polymer interactions. In contrast to the very slow dissolution rate of pure CBZ, dispersions of drug in polymers considerably improved the dissolution rate. This can be attributed to increased wettability and dispersibility, as well as decreased crystallinity and increase in amorphous fraction of drug. Solid dispersion formulations containing PEG 6000 and Povidone K 30 showed maximum drug release within one hour at the ratio of 1:1:1. Even physical mixtures of CBZ prepared with both carriers also showed better dissolution profiles than those of pure CBZ. In conclusions, solid dispersions could be a promising delivery of CBZ with improved oral bioavailability and immediate release profiles.

Keywords: carbamazepine, FTIR, kollidon 30, HPMC 6 CPS, PEG 6000, PEG 4000, poloxamer 407, water solubility, povidone k 30, SEM, solid dispersion

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10626 Erosion Wear of Cast Al-Si Alloys

Authors: Pooja Verma, Rajnesh Tyagi, Sunil Mohan

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Al-Si alloys are widely used in various components such as liner-less engine blocks, piston, compressor bodies and pumps for automobile sector and aerospace industries due to their excellent combination of properties like low thermal expansion coefficient, low density, excellent wear resistance, high corrosion resistance, excellent cast ability, and high hardness. The low density and high hardness of primary Si phase results in significant reduction in density and improvement in wear resistance of hypereutectic Al-Si alloys. Keeping in view of the industrial importance of the alloys, hypereutectic Al-Si alloys containing 14, 16, 18 and 20 wt. % of Si were prepared in a resistance furnace using adequate amount of deoxidizer and degasser and their erosion behavior was evaluated by conducting tests at impingement angles of 30°, 60°, and 90° with an erodent discharge rate of 7.5 Hz, pressure 1 bar using erosion test rig. Microstructures of the cast alloys were examined using Optical microscopy (OM) and scanning electron microscopy (SEM) and the presence of Si particles was confirmed by x-ray diffractometer (XRD). The mechanical properties and hardness were measured using uniaxial tension tests at a strain rate of 10-3/s and Vickers hardness tester. Microstructures of the alloys and X-ray examination revealed the presence of primary and eutectic Si particles in the shape of cuboids or polyhedral and finer needles. Yield strength (YS), ultimate tensile strength (UTS), and uniform elongation of the hypereutectic Al-Si alloys were observed to increase with increasing content of Si. The optimal strength and ductility was observed for Al-20 wt. % Si alloy which is significantly higher than the Al-14 wt. % Si alloy. The increased hardness and the strength of the alloys with increasing amount of Si has been attributed presence of Si in the solid solution which creates strain, and this strain interacts with dislocations resulting in solid-solution strengthening. The interactions between distributed primary Si particles and dislocations also provide Orowan strengthening leading to increased strength. The steady state erosion rate was found to decrease with increasing angle of impact as well as Si content for all the alloys except at 900 where it was observed to increase with the increase in the Si content. The minimum erosion rate is observed in Al-20 wt. % Si alloy at 300 and 600 impingement angles because of its higher hardness in comparison to other alloys. However, at 90° impingement angle the wear rate for Al-20 wt. % Si alloy is found to be the minimum due to deformation, subsequent cracking and chipping off material.

Keywords: Al-Si alloy, erosion wear, cast alloys, dislocation, strengthening

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10625 DNA Methylation Changes in Response to Ocean Acidification at the Time of Larval Metamorphosis in the Edible Oyster, Crassostrea hongkongensis

Authors: Yong-Kian Lim, Khan Cheung, Xin Dang, Steven Roberts, Xiaotong Wang, Vengatesen Thiyagarajan

Abstract:

Unprecedented rate of increased CO₂ level in the ocean and the subsequent changes in carbonate system including decreased pH, known as ocean acidification (OA), is predicted to disrupt not only the calcification process but also several other physiological and developmental processes in a variety of marine organisms, including edible oysters. Nonetheless, not all species are vulnerable to those OA threats, e.g., some species may be able to cope with OA stress using environmentally induced modifications on gene and protein expressions. For example, external environmental stressors, including OA, can influence the addition and removal of methyl groups through epigenetic modification (e.g., DNA methylation) process to turn gene expression “on or off” as part of a rapid adaptive mechanism to cope with OA. In this study, the above hypothesis was tested through testing the effect of OA, using decreased pH 7.4 as a proxy, on the DNA methylation pattern of an endemic and a commercially important estuary oyster species, Crassostrea hongkongensis, at the time of larval habitat selection and metamorphosis. Larval growth rate did not differ between control pH 8.1 and treatment pH 7.4. The metamorphosis rate of the pediveliger larvae was higher at pH 7.4 than those in control pH 8.1; however, over one-third of the larvae raised at pH 7.4 failed to attach to an optimal substrate as defined by biofilm presence. During larval development, a total of 130 genes were differentially methylated across the two treatments. The differential methylation in the larval genes may have partially accounted for the higher metamorphosis success rate under decreased pH 7.4 but with poor substratum selection ability. Differentially methylated loci were concentrated in the exon regions and appear to be associated with cytoskeletal and signal transduction, oxidative stress, metabolic processes, and larval metamorphosis, which implies the high potential of C. hongkongensis larvae to acclimate and adapt through non-genetic ways to OA threats within a single generation.

Keywords: adaptive plasticity, DNA methylation, larval metamorphosis, ocean acidification

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10624 Longitudinal Changes in Body Composition in Subjects with Diabetes Who Received Low-Carbohydrate Diet Education: The Effect of Age and Sex

Authors: Hsueh-Ching Wu

Abstract:

Aims: This study investigated the longitudinal changes in BC were evaluated in patients with T2D who received carbohydrate-restricted diet education (CRDE), and the effects of age and sex on BC were analyzed. Design: This retrospective observational study was conducted between 2018 and 2021. A total of 6164 T2D patients were analyzed. Subjects with T2D who received CRDE (daily carbohydrate intake: 26-45%). A hierarchical linear model (HLM) was used to estimate the change amount and rate of change for the following variables in each group: body weight (BW), body mass index (BMI), body fat mass (BFM), percent body fat (PBF), appendicular skeletal muscle mass (ASM), and skeletal muscle index (SMI). Results: The BW, BMI, ASM, SMI and BFM of T2D patients who received CRDE for 3 years decreased with increasing age; PBF showed the opposite trend. The changes in BW, BMI, ASM, and SMI of patients older than 65 years were higher than those of patients younger than 65 years, and the annual rate of decline for males was higher than that for females. The annual change in BFM and PBF for both sexes changed from a downward trend before the age of 65 to a slow increase after the age of 65, and the slow increase rate for women was higher than that for men. Conclusion: Changes in body composition are associated with age and sex. BW and muscle tissue decrease with age, and attention must be paid to the rebound of adipose tissue after middle age. Patient or Public Contribution: The patient agreed to participate in a retrospective chart review during in the study period.

Keywords: body weight, body composition, carbohydrate-restricted diet, nursing, type 2 diabetes

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10623 Establishing a Change Management Model for Precision Machinery Industry in Taiwan

Authors: Feng-Tsung Cheng, Shu-Li Wang, Mei-Fang Wu, , Hui-Yu Chuang

Abstract:

Due to the rapid development of modern technology, the widespread usage of the Internet makes business environment changing quickly. In order to be a leader in the global competitive market and to pursuit survive, “changing” becomes an unspoken rules need to follow for the company survival. The purpose of this paper is to build change model by using SWOT, strategy map, and balance scorecard, KPI and change management theory. The research findings indicate that organizational change plan formulated by the case company should require the employee to resist change factors and performance management system issues into consideration and must be set organizational change related programs, such as performance appraisal reward system, consulting and counseling mechanisms programs to improve motivation and reduce staff negative emotions. Then according to the model revised strategy maps and performance indicators proposed in this paper, such as strategy maps add and modify corporate culture, improve internal processes management, increase the growth rate of net income and other strategies. The performance indicators are based on strategy maps new and modified by adding net income growth rate, to achieve target production rate, manpower training achievement rates and other indicators, through amendments to achieve the company’s goal, be a leading brand of precision machinery industry.

Keywords: organizational change, SWOT analysis, strategy maps, performance indicators

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10622 The Analysis of the Two Dimensional Huxley Equation Using the Galerkin Method

Authors: Pius W. Molo Chin

Abstract:

Real life problems such as the Huxley equation are always modeled as nonlinear differential equations. These problems need accurate and reliable methods for their solutions. In this paper, we propose a nonstandard finite difference method in time and the Galerkin combined with the compactness method in the space variables. This coupled method, is used to analyze a two dimensional Huxley equation for the existence and uniqueness of the continuous solution of the problem in appropriate spaces to be defined. We proceed to design a numerical scheme consisting of the aforementioned method and show that the scheme is stable. We further show that the stable scheme converges with the rate which is optimal in both the L2 as well as the H1-norms. Furthermore, we show that the scheme replicates the decaying qualities of the exact solution. Numerical experiments are presented with the help of an example to justify the validity of the designed scheme.

Keywords: Huxley equations, non-standard finite difference method, Galerkin method, optimal rate of convergence

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10621 Quality Assurance Comparison of Map Check 2, Epid, and Gafchromic® EBT3 Film for IMRT Treatment Planning

Authors: Khalid Iqbal, Saima Altaf, M. Akram, Muhammad Abdur Rafaye, Saeed Ahmad Buzdar

Abstract:

Objective: Verification of patient-specific intensity modulated radiation therapy (IMRT) plans using different 2-D detectors has become increasingly popular due to their ease of use and immediate readout of the results. The purpose of this study was to test and compare various 2-D detectors for dosimetric quality assurance (QA) of intensity-modulated radiotherapy (IMRT) with the vision to find alternative QA methods. Material and Methods: Twenty IMRT patients (12 of brain and 8 of the prostate) were planned on Eclipse treatment planning system using Varian Clinac DHX on both energies 6MV and 15MV. Verification plans of all such patients were also made and delivered to Map check2, EPID (Electronic portal imaging device) and Gafchromic EBT3. Gamma index analyses were performed using different criteria to evaluate and compare the dosimetric results. Results: Statistical analysis shows the passing rate of 99.55%, 97.23% and 92.9% for 6MV and 99.53%, 98.3% and 94.85% for 15 MV energy using a criteria of ±5% of 3mm, ±3% of 3mm and ±3% of 2mm respectively for brain, whereas using ±5% of 3mm and ±3% of 3mm gamma evaluation criteria, the passing rate is 94.55% and 90.45% for 6MV and 95.25%9 and 95% for 15 MV energy for the case of prostate using EBT3 film. Map check 2 results shows the passing rates of 98.17%, 97.68% and 86.78% for 6MV energy and 94.87%,97.46% and 88.31% for 15 MV energy respectively for brain using a criteria of ±5% of 3mm, ±3% of 3mm and ±3% of 2mm, whereas using ±5% of 3mm and ±3% of 3mm gamma evaluation criteria gives the passing rate of 97.7% and 96.4% for 6MV and 98.75%9 and 98.05% for 15 MV energy for the case of prostate. EPID 6 MV and gamma analysis shows the passing rate of 99.56%, 98.63% and 98.4% for the brain, 100% and 99.9% for prostate using the same criteria as for map check 2 and EBT 3 film. Conclusion: The results demonstrate excellent passing rates were obtained for all dosimeter when compared with the planar dose distributions for 6 MV IMRT fields as well as for 15 MV. EPID results are better than EBT3 films and map check 2 because it is likely that part of this difference is real, and part is due to manhandling and different treatment set up verification which contributes dose distribution difference. Overall all three dosimeter exhibits results within limits according to AAPM report.120.

Keywords: gafchromic EBT3, radiochromic film dosimetry, IMRT verification, EPID

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10620 Prevalence of Gastrointestinal Nematodes of Farm Animals by Copro-Culture

Authors: Mosaab A. Omar, Mohammad Saleh Al-Aboody

Abstract:

In the present study, examination of 442 faecal samples was performed: 171 from cattle, 128 from buffaloes and 143 from sheep. During the period from May, 2014 to April, 2015, fecal examination showed the infection rate with abomasal nematodes was 30% in cattle, 22.6% in buffaloes, and 31.4% in sheep. Fecal culture gave results of 47.5%, 30%, and 50.3% in cattle, buffaloes and sheep respectively. Seasonal infection with abomasal nematodes as shown by faecal culture in cattle, reveals the highest infection rate is in summer (55.9%), followed by spring (54.1%), autumn (50%), and winter (33.3%). Cooperia spp. is the most prevalent larva in both cattle and buffaloes; Strongyloides papillosus is the most predominant one in sheep. Here we introduce the first study of abomasal worms infection in ruminants in Qena, Egypt. The prevalence is found to be so high among the all examined animals, that we recommend that the authorities apply suitable control programs.

Keywords: haemonchus, ostertagia, seasonal dynamics, floatation

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10619 Lignin Pyrolysis to Value-Added Chemicals: A Mechanistic Approach

Authors: Binod Shrestha, Sandrine Hoppe, Thierry Ghislain, Phillipe Marchal, Nicolas Brosse, Anthony Dufour

Abstract:

The thermochemical conversion of lignin has received an increasing interest in the frame of different biorefinery concepts for the production of chemicals or energy. It is needed to better understand the physical and chemical conversion of lignin for feeder and reactor designs. In-situ rheology reveals the viscoelastic behaviour of lignin upon thermal conversion. The softening, re-solidification (char formation), swelling and shrinking behaviours are quantified during pyrolysis in real-time [1]. The in-situ rheology of an alkali lignin (Protobind 1000) was conducted in high torque controlled strain rheometer from 35°C to 400°C with a heating rate of 5°C.min-1. The swelling, through glass phase transition overlapped with depolymerization, and solidification (crosslinking and “char” formation) are two main phenomena observed during lignin pyrolysis. The onset of temperatures for softening and solidification for this lignin has been found to be 141°C and 248°C respectively. An ex-situ characterization of lignin/char residues obtained at different temperatures after quenching in the rheometer gives a clear understanding of the pathway of lignin degradation. The lignin residues were sampled from the mid-point temperatures of the softening range and solidification range to study the chemical transformations undergoing. Elemental analysis, FTIR and solid state NMR were conducted after quenching the solid residues (lignin/char). The quenched solid was also extracted by suitable solvent and followed by acetylation and GPC-UV analysis. The combination of 13C NMR and GPC-UV reveals the depolymerization followed by crosslinking of lignin/char. NMR and FTIR provide the evolution of functional moieties upon temperature. Physical and chemical mechanisms occurring during lignin pyrolysis are accounted in this study. Thanks to all these complementary methods.

Keywords: pyrolysis, bio-chemicals, valorization, mechanism, softening, solidification, cross linking, rheology, spectroscopic methods

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10618 Experimental Analysis of Electrical Energy Producing Using the Waste Heat of Exhaust Gas by the Help of Thermoelectric Generator

Authors: Dilek Ozlem Esen, Mesut Kaya

Abstract:

The focus of this study is to analyse the results of heat recovery from exhaust gas which is produced by an internal combustion engine (ICE). To obtain a small amount of energy, an exhaust system which is suitable for recovery waste heat has been constructed. Totally 27 TEGs have been used to convert from the heat to electric energy. By producing a small amount of this energy by the help of thermoelectric generators can reduce engine loads thus decreasing pollutant emissions, fuel consumption, and CO2. This case study is conducted in an effort to better understand and improve the performance of thermoelectric heat recovery systems for automotive use. As a result of this study, 0,45 A averaged current rate, 13,02 V averaged voltage rate and 5,8 W averaged electrical energy have been produced in a five hours operation time.

Keywords: thermoelectric, peltier, thermoelectric generator (TEG), exhaust, cogeneration

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10617 Patient Perspectives on the Role of Orthopedic Nurse Practitioners: A Cross-Sectional Study

Authors: Merav Ben Natan, May Revach, Or Sade, Yaniv Yonay, Yaron Berkovich

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Background: The inclusion of nurse practitioners (NPs) specializing in orthopedics holds promise for enhancing the quality of care for orthopedic patients. Understanding patients’ perspectives on this role is crucial for evaluating the feasibility and acceptance of integrating NPs into orthopedic settings. This study aims to explore the receptiveness of orthopedic patients to treatment by orthopedic NPs and examines potential associations between patients’ willingness to engage with NPs, their familiarity with the NP role, perceptions of nursing, and satisfaction with orthopedic nursing care. Methods: This cross-sectional study involved patients admitted to an orthopedic department at a central Israeli hospital between January and February 2023. Data was collected using a validated questionnaire consisting of five sections, reviewed by content experts. Statistical analyses were conducted using SPSS and included descriptive statistics, independent samples t-tests, Pearson correlations, and linear regression. Results: Participants in the study showed a moderate willingness to receive treatment from orthopedic NPs, with more than two-thirds expressing strong openness. Patients were generally receptive to NPs performing various clinical tasks, though there was less enthusiasm for NPs’ involvement in medication management and preoperative evaluations. Positive attitudes towards nurses and familiarity with the NP role were significant predictors of patient receptiveness to NP treatment. Conclusion: Patient acceptance of orthopedic NPs varies across different aspects of care. While there is a general willingness to receive care from NPs, these nuanced preferences must be considered when implementing NPs in orthopedic settings. Awareness and positive perceptions of the NP role play crucial roles in shaping patients’ willingness to engage with NPs.

Keywords: orthopedic nurse practitioners, patient receptiveness, perceptions of nursing, clinical tasks

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10616 Correlation Analysis between Physical Fitness Norm and Cardio-Pulmonary Signals under Graded Exercise and Recovery

Authors: Shyan-Lung Lin, Cheng-Yi Huang, Tung-Yi Lin

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Physical fitness is the adaptability of the body to physical work and the environment, and is generally known to include cardiopulmonary-fitness, muscular-fitness, body flexibility, and body composition. This paper is aimed to study the ventilatory and cardiovascular activity under various exercise intensities for subjects at distinct ends of cardiopulmonary fitness norm. Three graded upright biking exercises, light, moderate, and vigorous exercise, were designed for subjects at distinct ends of cardiopulmonary fitness norm from their physical education classes. The participants in the experiments were 9, 9, and 11 subjects in the top 20%, middle 20%, and bottom 20%, respectively, among all freshmen of the Feng Chia University in the academic year of 2015. All participants were requested to perform 5 minutes of upright biking exercise to attain 50%, 65%, and 85% of their maximum heart rate (HRmax) during the light, moderate, and vigorous exercise experiment, respectively, and 5 minutes of recovery following each graded exercise. The cardiovascular and ventilatory signals, including breathing frequency (f), tidal volume (VT), heart rate (HR), mean arterial pressure (MAP), and ECG signals were recorded during rest, exercise, and recovery periods. The physiological signals of three groups were analyzed based on their recovery, recovery rate, and percentage variation from rest. Selected time domain parameters, SDNN and RMSSD, were computed and spectral analysis was performed to study the hear rate variability from collected ECG signals. The comparison studies were performed to examine the correlations between physical fitness norm and cardio-pulmonary signals during graded exercises and exercise recovery. No significant difference was found among three groups with VT during all levels of exercise intensity and recovery. The top 20% group was found to have better performance in heart recovery (HRR), frequency recovery rate (fRR) and percentage variation from rest (Δf) during the recovery period of vigorous exercise. The top 20% group was also found to achieve lower mean arterial pressure MAP only at rest but showed no significant difference during graded exercises and recovery periods. In time-domain analysis of HRV, the top 20% group again seemed to have better recovery rate and less variation in terms of SDNN during recovery period of light and vigorous exercises. Most assessed frequency domain parameters changed significantly during the experiment (p<0.05, ANOVA). The analysis showed that the top 20% group, in comparison with middle and bottom 20% groups, appeared to have significantly higher TP, LF, HF, and nHF index, while the bottom 20% group showed higher nLF and LF/HF index during rest, three graded levels of exercises, and their recovery periods.

Keywords: physical fitness, cardio-pulmonary signals, graded exercise, exercise recovery

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10615 Authorization of Commercial Communication Satellite Grounds for Promoting Turkish Data Relay System

Authors: Celal Dudak, Aslı Utku, Burak Yağlioğlu

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Uninterrupted and continuous satellite communication through the whole orbit time is becoming more indispensable every day. Data relay systems are developed and built for various high/low data rate information exchanges like TDRSS of USA and EDRSS of Europe. In these missions, a couple of task-dedicated communication satellites exist. In this regard, for Turkey a data relay system is attempted to be defined exchanging low data rate information (i.e. TTC) for Earth-observing LEO satellites appointing commercial GEO communication satellites all over the world. First, justification of this attempt is given, demonstrating duration enhancements in the link. Discussion of preference of RF communication is, also, given instead of laser communication. Then, preferred communication GEOs – including TURKSAT4A already belonging to Turkey- are given, together with the coverage enhancements through STK simulations and the corresponding link budget. Also, a block diagram of the communication system is given on the LEO satellite.

Keywords: communication, GEO satellite, data relay system, coverage

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10614 An Automatic Speech Recognition Tool for the Filipino Language Using the HTK System

Authors: John Lorenzo Bautista, Yoon-Joong Kim

Abstract:

This paper presents the development of a Filipino speech recognition tool using the HTK System. The system was trained from a subset of the Filipino Speech Corpus developed by the DSP Laboratory of the University of the Philippines-Diliman. The speech corpus was both used in training and testing the system by estimating the parameters for phonetic HMM-based (Hidden-Markov Model) acoustic models. Experiments on different mixture-weights were incorporated in the study. The phoneme-level word-based recognition of a 5-state HMM resulted in an average accuracy rate of 80.13 for a single-Gaussian mixture model, 81.13 after implementing a phoneme-alignment, and 87.19 for the increased Gaussian-mixture weight model. The highest accuracy rate of 88.70% was obtained from a 5-state model with 6 Gaussian mixtures.

Keywords: Filipino language, Hidden Markov Model, HTK system, speech recognition

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10613 Cost-Effectiveness Analysis of the Use of COBLATION™ Knee Chondroplasty versus Mechanical Debridement in German Patients

Authors: Ayoade Adeyemi, Leo Nherera, Paul Trueman, Antje Emmermann

Abstract:

Background and objectives: Radiofrequency (RF) generated plasma chondroplasty is considered a promising treatment alternative to mechanical debridement (MD) with a shaver. The aim of the study was to perform a cost-effectiveness analysis comparing costs and outcomes following COBLATION chondroplasty versus mechanical debridement in patients with knee pain associated with a medial meniscus tear and idiopathic ICRS grade III focal lesion of the medial femoral condyle from a payer perspective. Methods: A decision-analytic model was developed comparing economic and clinical outcomes between the two treatment options in German patients following knee chondroplasty. Revision rates based on the frequency of repeat arthroscopy, osteotomy and conversion to total knee replacement, reimbursement costs and outcomes data over a 4-year time horizon were extracted from published literature. One-way sensitivity analyses were conducted to assess uncertainties around model parameters. Threshold analysis determined the revision rate at which model results change. All costs were reported in 2016 euros, future costs were discounted at a 3% annual rate. Results: Over a 4 year period, COBLATION chondroplasty resulted in an overall net saving cost of €461 due to a lower revision rate of 14% compared to 48% with MD. Threshold analysis showed that both options were associated with comparable costs if COBLATION revision rate was assumed to increase up to 23%. The initial procedure costs for COBLATION were higher compared to MD and outcome scores were significantly improved at 1 and 4 years post-operation versus MD. Conclusion: The analysis shows that COBLATION chondroplasty is a cost-effective option compared to mechanical debridement in the treatment of patients with a medial meniscus tear and idiopathic ICRS grade III defect of the medial femoral condyle.

Keywords: COBLATION, cost-effectiveness, knee chondroplasty, mechanical debridement

Procedia PDF Downloads 394