Search results for: no observed adverse effect level

Authors: S. Ritddech, P. Aroonjarattham, K. Aroonjarattham

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The pullout strength had an effect on the stability of plate screw fixation when inserted in the cervical spine. Nine different titanium alloy bone screws were used to test the pullout strength through finite element analysis. The result showed that the Moss Miami I can bear the highest pullout force at 1,075 N, which causes the maximum von Mises stress at 858.87 MPa, a value over the yield strength of titanium. The bone screw should have large outer diameter, core diameter and proximal root radius to increase the pullout strength.

Keywords: pullout strength, screw parameter, cervical spine, finite element analysis

Procedia PDF Downloads 298

Authors: Shahira El Shafie, Hanaa Eldash, Engy Ghabbour, Mohamed Eid

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Several immunologic defects can be found in patients with beta-thalassemia, among which the impairment of neutrophil phagocytic function is of utmost importance. Attention has been directed to the role of proinflammatory cytokines in neutrophil chemotaxis and phagocytosis. Interleukin-8 (IL-8) is an important chemotactic and activation peptide for neutrophils; changes in IL-8 level and potential correlation with neutrophil function can be relevant to immunomodulation pathophysiology in beta-thalassemia patients. This case-control study aimed to evaluate IL-8 level and to assess granulocyte recruitment, as markers of immunomodulation, in poly-transfused thalassemia patients attending Fayoum University Hospitals. The study was conducted on 50 patients with ß thalassemia and 32 age-matched controls. 21/50 patients were transfused more than ten times, and 29/50 were transfused in a lower frequency. Patients and controls were subjected to thorough history taking and clinical examination, measurement of IL-8 level using human IL-8 ELISA kit, and Rebuck skin window technique (RSWT) to assess granulocyte recruitment. Our data showed statistically significant higher levels of IL-8 in ß thalassemia patients compared to control with a much higher difference in patients transfused more than ten times. Neutrophil recruitment was significantly lower in ß thalassemia patients compared to control at 4 hours and 24 hours test time. Although IL-8, the main chemotactic pro-inflammatory cytokine showed a higher level in thalassemia patients, neutrophils recruitment was significantly lower, especially in those receiving more than ten transfusion times. Our findings suggest a possible role of other neutrophil chemotactic factors, defective neutrophil response, or increased IL-8 as compensation of abnormal function. We recommend the use of IL-8 and Rebuck skin window technique as useful markers of immunomodulation in thalassemia and further study for these biomarkers to assess their clinical implications and impact on the management of thalassemia patients.

Keywords: beta-thalassemia, Interleukin-8, Rebuck skin window technique, immunomodulation

Procedia PDF Downloads 194

Authors: T. A. Sakr, Hanaa E. Abd-El-Mottaleb

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Outrigger-braced wall systems are commonly used to provide high rise buildings with the required lateral stiffness for wind and earthquake resistance. The existence of outriggers adds to the stiffness and strength of walls as reported by several studies. The effects of different parameters on the elasto-plastic dynamic behavior of outrigger-braced wall systems to earthquakes are investigated in this study. Parameters investigated include outrigger stiffness, concrete strength, and reinforcement arrangement as the main design parameters in wall design. In addition to being significant to the wall behavior, such parameters may lead to the change of failure mode and the delay of crack propagation and consequently failure as the wall is excited by earthquakes. Bi-linear stress-strain relation for concrete with limited tensile strength and truss members with bi-linear stress-strain relation for reinforcement were used in the finite element analysis of the problem. The famous earthquake record, El-Centro, 1940 is used in the study. Emphasis was given to the lateral drift, normal stresses and crack pattern as behavior controlling determinants. Results indicated significant effect of the studied parameters such that stiffer outrigger, higher grade concrete and concentrating the reinforcement at wall edges enhance the behavior of the system. Concrete stresses and cracking behavior are sigbificantly enhanced while lesser drift improvements are observed.

Keywords: outrigger, shear wall, earthquake, nonlinear

Procedia PDF Downloads 289

Authors: Zehui Du, Chaiwat Prapainainar, Paisan Kongkachuichay, Paweena Prapainainar

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The aim of this work was to obtain small crystalline size and high crystallinity of mordenites and analcimes, by modifying the aging time, agitation, water content, crystallization temperature and crystallization time. Two different hydrothermal methods were studied. Both methods used Na2SiO3 as the silica source, NaAlO2 as the aluminum source, and NaOH as the alkali source. The first method used HMI as the template while the second method did not use the template. Mordenite crystals with spherical shape and bimodal in size of about 1 and 5 µm were obtained from the first method using conditions of 24 hr aging time, 170°C and 24 hr crystallization. Modernites with high crystallinity were formed using agitation system in the crystallization process. It was also found that the aging time of 2 hr and 24 hr did not much affect the formation of mordenite crystals. Analcime crystals were formed in spherical shape and facet on surface with the size between 13-15 µm by the second method using the conditions of 30 minutes aging time, 170°C and 24 hr crystallization without calcination. By increasing water content, the crystallization process was slowed down and resulted in smaller analcime crystals. Larger size of analcime crystals were observed when the samples were calcined at 300°C and 580°C. Higher calcination temperature led to higher crystal growth and resulted in larger crystal size. Finally, mordenite and analcime was used as fillers in zeolite/Nafion composite membrane to solve the fuel cross over problem in direct alcohol fuel cell.

Keywords: analcime, hydrothermal synthesis, mordenite, zeolite

Procedia PDF Downloads 269

Authors: Tokihiko Akita, Seiichi Mita

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A millimeter-wave radar is the most robust against adverse environments, making it an essential environment recognition sensor for automated driving. However, the reflection signal is sparse and unstable, so it is difficult to obtain the high recognition accuracy. Deep learning provides high accuracy even for them in recognition, but requires large scale datasets with ground truth. Specially, it takes a lot of cost to annotate for a millimeter-wave radar. For the solution, utilizing a simulator that can generate an annotated huge dataset is effective. Simulation of the radar is more difficult to match with real world data than camera image, and recognition by deep learning with higher-order features using the simulator causes further deviation. We have challenged to improve the accuracy of traffic participant classification by fusing simulator and real-world data with domain adaptation technique. Experimental results with the domain adaptation network created by us show that classification accuracy can be improved even with a few real-world data.

Keywords: millimeter-wave radar, object classification, deep learning, simulation, domain adaptation

Procedia PDF Downloads 98

Authors: Tanveer Iqbal, Saima Yasin, Muhammad Zafar, Ahmad Shakeel, Fahad Nazir, Paul F. Luckham

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The contact performance of polymeric composites is dependent on the localized mechanical properties of materials. This is particularly important for fiber oriented polymeric materials where self-lubrication from top layers has been the basic requirement. The nanoindentation response of fiber reinforced poly(etheretherketone), PEEK, composites have been evaluated to determine the near-surface mechanical characteristics. Load-displacement compliance, hardness and elastic modulus data based on contact compliance mode (CSM) indentation of carbon fiber oriented and glass fiber oriented PEEK composites are reported as a function of indentation contact displacement. The composite surfaces were indented to a maximum penetration depth of 5µm using Berkovich tip indenter. A typical multiphase response of the composite surface is depicted from analysis of the indentation data for the composites, showing presence of polymer matrix, fibers, and interphase regions. The observed experimental results show that although the surface mechanical properties of carbon fiber based PEEK composite were comparatively higher, the properties of matrix material were seen to be increased in the presence of glass fibers. The experimental methodology may provide a convenient means to understand morphological description of the multimodal polymeric composites.

Keywords: nanoindentation, PEEK, modulus, hardness, plasticization

Procedia PDF Downloads 196

Authors: Chen Shuwen, Nunthapin Chantachaimongkol

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Since the world has moved into a transitional period, known as globalization; the business environment is now more complicated than ever before. Corporate information has become a matter of great importance for stakeholders, in order to understand the current situation. As a result of this, the concept of corporate governance has been broadly introduced to manage and control the affairs of corporations while businesses are required to disclose both financial and non-financial information to public via various communication channels such as the annual report, the financial report, the company’s website, etc. However, currently there are several other issues related to asymmetric information such as moral hazard or adverse selection that still occur intensively in workplaces. To prevent such problems in the business, it is required to have an understanding of what factors strengthen their transparency, accountability, fairness, and responsibility. Under aforementioned arguments, this paper aims to propose a conceptual framework that enables an investigation on how corporate governance mechanism influences disclosure efficiency of listed companies in the Association of Southeast Asia Nations (ASEAN) and the factors that should be considered for further development of good behaviors, particularly in regards to voluntary disclosure practices. To achieve its purpose, extensive reviews of literature are applied as a research methodology. It is divided into three main steps. Firstly, the theories involved with both corporate governance and disclosure practices such as agency theory, contract theory, signaling theory, moral hazard theory, and information asymmetry theory are examined to provide theoretical backgrounds. Secondly, the relevant literatures based on multi- perspectives of corporate governance, its attributions and their roles on business processes, the influences of corporate governance mechanisms on business performance, and the factors determining corporate governance characteristics as well as capability are reviewed to outline the parameters that should be included in the proposed model. Thirdly, the well-known regulatory document OECD principles and previous empirical studies on the corporate disclosure procedures are evaluated to identify the similarities and differentiations with the disclosure patterns in the ASEAN. Following the processes and consequences of the literature review, abundant factors and variables are found. Further to the methodology, additional critical factors that also have an impact on the disclosure behaviors are addressed in two groups. In the first group, the factors which are linked to the national characteristics - the quality of national code, legal origin, culture, the level of economic development, and so forth. Whereas in the second group, the discoveries which refer to the firm’s characteristics - ownership concentration, ownership’s rights, controlling group, and so on. However, because of research limitations, only some literature are chosen and summarized to form part of the conceptual framework that explores the relationship between corporate governance and the disclosure practices of listed companies in ASEAN.

Keywords: corporate governance, disclosure practice, ASEAN, listed company

Procedia PDF Downloads 196

Authors: Nadia Yaghoobi, Seyed Majid Esmaeilzadeh

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Due to advancements in wireless communication, new sensor capabilities have been created. In addition to the automation industry, the Internet of Things (IoT) has been used in environmental issues and has provided the possibility of communication between different devices for data collection and exchange. Water quality depends on many factors which are essential for maintaining the minimum sustainability of water. Regarding the great dependence of fishes on the quality of the aquatic environment, water quality can directly affect their activity. Therefore, monitoring water quality is an important issue to consider, especially in the fish farming industry. The conventional method of water quality testing is to collect water samples manually and send them to a laboratory for testing and analysis. This time-consuming method is a waste of manpower and is not cost-effective. The water quality measurement system implemented in this project monitors water quality in real-time through various sensors (parameters: water temperature, water level, dissolved oxygen, humidity and ambient temperature, water turbidity, PH). The Wi-Fi module, ESP8266, transmits data collected by sensors wirelessly to ThingSpeak and the smartphone app. Also, with the help of these instantaneous data, water temperature and water level can be controlled by using a heater and a water pump, respectively. This system can have a detailed study of the pollution and condition of water resources and can provide an environment for safe fish farming.

Keywords: dissolved oxygen, IoT, monitoring, ThingSpeak, water level, water quality, WiFi module

Procedia PDF Downloads 199

Authors: Kateryna Zhdanova, Evelyn Szeinbaum, Michelle Lo, Yeonjae Jo, Abel E. Navarro

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Alginate hydrogel beads (AB), spent peppermint leaf (PM), and a hybrid adsorbent of these two materials (ABPM) were studied as potential biosorbents of Cobalt (II) ions from aqueous solutions. Cobalt ion is a commonly underestimated pollutant that is responsible for several health problems. Discontinuous batch experiments were conducted at room temperature to evaluate the effect of solution acidity, mass of adsorbent on the adsorption of Co(II) ions. The interfering effect of salinity, the presence of surfactants, an organic dye, and Pb(II) ions were also studied to resemble the application of these adsorbents in real wastewater. Equilibrium results indicate that Co(II) uptake is maximized at pH values higher than 5, with adsorbent doses of 200 mg, 200 mg, and 120 mg for AB, PM, and ABPM, respectively. Co(II) adsorption followed the trend AB > ABPM > PM with Adsorption percentages of 77%, 71% and 64%, respectively. Salts had a strong negative effect on the adsorption due to the increase of the ionic strength and the competition for adsorption sites. The presence of Pb(II) ions, surfactant, and dye BY57 had a slightly negative effect on the adsorption, apparently due to their interaction with different adsorption sites that do not interfere with the removal of Co(II). A polar-electrostatic adsorption mechanism is proposed based on the experimental results. Scanning electron microscopy indicates that adsorbent has appropriate morphological and textural properties, and also that ABPM encapsulated most of the PM inside of the hydrogel beads. These experimental results revealed that AB, PM, and ABPM are promising adsorbents for the elimination of Co(II) ions from aqueous solutions under different experimental conditions. These biopolymers are proposed as eco-friendly alternatives for the removal of heavy metal ions at lower costs than the conventional techniques.

Keywords: adsorption, Co(II) ions, alginate hydrogel beads, spent peppermint leaf, pH

Procedia PDF Downloads 132

Authors: Reza Hadjiaghaie Vafaie, Sevda Givtaj

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Automation and control of biological samples and solutions at the microscale is a major advantage for biochemistry analysis and biological diagnostics. Despite the known potential of miniaturization in biochemistry and biomedical applications, comparatively little is known about fluid automation and control at the microscale. Here, we study the electric field effect inside a fluidic channel and proper electrode structures with different patterns proposed to form forward, reversal, and rotational flows inside the channel. The simulation results confirmed that the ac electro-thermal flow is efficient for the control and automation of high-conductive solutions. In this research, the fluid pumping and mixing effects were numerically studied by solving physic-coupled electric, temperature, hydrodynamic, and concentration fields inside a microchannel. From an experimental point of view, the electrode structures are deposited on a silicon substrate and bonded to a PDMS microchannel to form a microfluidic chip. The motions of fluorescent particles in pumping and mixing modes were captured by using a CCD camera. By measuring the frequency response of the fluid and exciting the electrodes with the proper voltage, the fluid motions (including pumping and mixing effects) are observed inside the channel through the CCD camera. Based on the results, there is good agreement between the experimental and simulation studies.

Keywords: microfluidic, nano/micro actuator, AC electrothermal, Reynolds number, micropump, micromixer, microfabrication, mass transfer, biomedical applications

Procedia PDF Downloads 66

Authors: Zhemi Xu, Dewei Chu, Sean Li

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Well self-assembled pure and Mn-doped SnO2 nanocubes were synthesized by interface thermodynamic method, which is ideal for highly homogeneous large scale thin film deposition on flexible substrates for various electric devices. Mn-doped SnO2 shows very good resistive switching with high On/Off ratio (over 103), endurance and retention characteristics. More important, the resistive state can be tuned by multi-layer fabrication by alternate pure SnO2 and Mn-doped SnO2 nanocube layer, which improved the memory capacity of resistive switching effectively. Thus, such a method provides transparent, multi-level resistive switching for next generation non-volatile memory applications.

Keywords: metal oxides, self-assembly nanoparticles, multi-level resistive switching, multi-layer thin film

Procedia PDF Downloads 345

Authors: Ahmed Ibrahim Galadima, Abdullahi Muhammed Bello, Abdullateef Akintunde Raji, Ruqayyah Mujahidah Abdullateef, Hajara Sani Labaran

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Sesamum indicium is an erect, herbaceous, branched, and warm-season annual crop. It differs in growth habit, form and shape, seed size and color, composition, size, and color of flowers. The experiments were performed by collecting two accessions of Sesamum indicum (white and black varieties). The morphological parameters like plant height and leaf size were measured using a ruler, while stem girth was observed using a vernier caliper. Germinability assessments were conducted by placing 100 seeds from each of the two sesame varieties and presoaked in 5 per cent sodium hypochlorite for 15 min., followed by rinse with distilled water. Germinability was assessed by placing the seeds in moist conditions and analyzing the outcome accordingly. The results from the experiments showed that the plant height (41.98 cm), stem girth (3.23 cm), and size of leaves (13.89 cm2) were higher in the white sesame variety when compared to the sesame black variety where 34.30 cm, 2.68 cm, and 7.47 cm2, respectively were obtained. But, from the black sesame variety, the number of leaves and the number of branches high values (105.06 cm) and (10.41), respectively were discovered. And significant differences were recorded in all the analyzed morphological parameters between the two sesame accessions, except stem girth. More so, the white variety of the sesame plant has demonstrated a good reproductive capability with the number of flowers (7.18), number of capsules (17.44), 100 seeds weight (1.67 g), and 1000 seeds weight (16.67 g). However, none of the analyzed reproductive parameters was observed from the black sesame variety. The white sesame variety was observed to have a higher number of Trichomes per microscopic view by almost 7 folds when compared to the black variety. But, improved size of stomata was detected in the black sesame variety by over 1.5 folds compared to the white variety. The germinability analysis had shown that from the sesame white variety, 98 seeds out of the 100 seeds sown were able to germinate, which signifies 98 percent germinability. Whereas 86 seeds out of the 100 seeds sown have germinated in petri dishes from the black sesame variety, which suggests 86 per cent germinability. Therefore, this research obviously showed that the white sesame variety displayed remarkable morphological qualities and, accordingly could be employed for farming purposes.

Keywords: accessions of sesame plant, characterization, growth, morphology

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Authors: Ali Showail Ali Alasmari

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Introduction: Cataract is the loss of transparency of the lens inside the eye. It is the most common cause of visual loss and blindness worldwide. This study provides a systemic review of the recent findings on the association of vitamin D, and vitamin B12, and their possible role in preventing cataracts in senile (S) and diabetic mellitus (DM) patient groups. Objective: This study was intended to establish and investigate if there is any role between vitamin D and vitamin B12? Secondly, the connection between serum level of vitamin D and vitamin B12 in cataract incidence senile (s) vs. diabetic mellitus (DM) cataract patient groups. Furthermore, to evaluate and analyze cataract occurrence regarding vitamin D and vitamin B12 levels with other risk factors. Finally, to evaluate lens opacities pre and post treatment with vitamin D and vitaminB12 linked to age and visual acuity loss in both senile(S) and diabetic mellitus (DM) cataract patients’ groups. Methods: This study conducted at the ophthalmology clinic at Muhyail General Hospital. Select a prospective case-control to study the effect of vitamin D and Vit B12 on senile(S) cataracts that caused by age and diabetic mellitus (DM)cataract patients; then we compare these two groups. This study prospectively enrolled a total of 50 samples, 25 with senile cataract and 25 with diabetic cataract, from ophthalmology clinic at Muhyail General Hospital. Measuring 25-hydroxy vitamin D and vitamin B12 level concentrations in the assigned samples. Analyses were performed using SAS (statistical analysis software) program. Results: The most important finding in this study was that the senile(s) cataract patients’ group greatly benefited by the combination therapy of vitamin D, and Vitamin B12 reached (28.5±1.50 and 521.1±21.10) respectively; on the contrary, the diabetic cataract patient group hardly shows any significant improvement (21.5 ± 1.00 and 197.2 ± 7.20) respectively. This is because of the Metformin, the first line drug for treating diabetes, has been reported to potentially decrease vitamin B-12 status. This epigenetic modification was correlated with the diabetic mellitus (DM) cataract patients’ group not responding. Vitamin B12 deficiency also leads to an impairment of the conversion of methylmalonyl-CoA to succinyl-CoA, which has been associated with insulin resistance. There was no significant difference between the age, body mass index (BMI), the mean of Vit-D pre-treatments, and the mean values of Hemoglobin A1C of both senile (S) and diabetic mellitus (DM) cataract patient groups. On other hand, there was a highly significant difference between the mean values of glucose levels in both senile (S) and diabetic mellitus (DM) cataract patient groups. Conclusion: Here we conclude that diabetic mellitus (DM) cataract patient group hardly benefited from this combination therapy vitamin D and vitamin B12; on the other hand senile patient group (s) benefited a lot from the therapy.

Keywords: cataract patients, senile, diabetes mellitus, vitamin B12, vitamin D, Muhyail General Hospital, Saudi Arabia

Procedia PDF Downloads 109

Authors: Yan-Shen Yang, Bai-Chen Xie

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Background and significance of the study: Both green power trading schemes and interregional power transmission are effective ways to increase green power absorption and achieve renewable power development goals. China accelerates the construction of interregional power transmission lines and the green power market. A critical issue focusing on the close interaction between these two approaches arises, which can heavily affect the green power quota allocation and renewable power development. Existing studies have not discussed this issue adequately, so it is urgent to figure out their relationship to achieve a suitable power market design and a more reasonable power grid construction.Basic methodologies: We develop an equilibrium model of the power market in China to analyze the coupling effect of these two approaches as well as their influence on power generation and interregional transmission in China. Our model considers both the Tradable green certificate (TGC) and green power market, which consists of producers, consumers in the market, and an independent system operator (ISO) minimizing the total system cost. Our equilibrium model includes the decision optimization process of each participant. To reformulate the models presented as a single-level one, we replace the producer, consumer, ISO, and market equilibrium problems with their Karush-Kuhn-Tucker (KKT) conditions, which is further reformulated as a mixed-integer linear programming (MILP) and solved in Gurobi solver. Major findings: The result shows that: (1) the green power market can significantly promote renewable power absorption while the TGC market provides a more flexible way for green power trading. (2) The phenomena of inefficient occupation and no available transmission lines appear simultaneously. The existing interregional transmission lines cannot fully meet the demand for wind and solar PV power trading in some areas while the situation is vice versa in other areas. (3) Synchronous implementation of green power and TGC trading mechanism can benefit the development of green power as well as interregional power transmission. (4) The green power transaction exacerbates the unfair distribution of carbon emissions. The Carbon Gini Coefficient is up to 0.323 under the green power market which shows a high Carbon inequality. The eastern coastal region will benefit the most due to its huge demand for external power.

Keywords: green power market, tradable green certificate, interregional power transmission, power market equilibrium model

Procedia PDF Downloads 154

Authors: M. Olmedilla, M. R. Martinez-Torres, S. L. Toral

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Electronic Word-Of-Mouth (eWOM) communities represent today an important source of information in which more and more customers base their purchasing decisions. They include thousands of reviews concerning very different products and services posted by many individuals geographically distributed all over the world. Due to their massive audience, eWOM communities can help users to find the product they are looking for even if they are less popular or rare. This is known as the long tail effect, which leads to a larger number of lower-selling niche products. This paper analyzes the long tail effect in a well-known eWOM community and defines a tool for finding niche products unavailable through conventional channels.

Keywords: eWOM, online user reviews, long tail theory, product categorization, social network analysis

Procedia PDF Downloads 427

Authors: Maher Agi, Hardik Soni

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This paper presents a deterministic model for optimized control of the inventory of a perishable product subject to both physical deterioration and degradation of its freshness condition. The demand for the product depends on its current inventory level and freshness condition. Our model allows for any positive amount of end of cycle inventory. Some useful conditions that characterize the optimal solution of the model are derived and an algorithm is presented for finding the optimal values of the price, the inventory cycle, the end of cycle inventory level and the order quantity. Numerical examples are then given. Our work shows how the product freshness in conjunction with the inventory deterioration affects the inventory management decisions.

Keywords: inventory management, lot sizing, perishable products, deteriorating inventory, age-dependent demand, stock-dependent demand

Procedia PDF Downloads 239

Authors: Marielle Leijten, Catherine Meulemans, Sven De Maeyer, Luuk Van Waes

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For the diagnosis of Alzheimer's disease (AD), a large variety of neuropsychological tests are available. In some of these tests, linguistic processing - both oral and written - is an important factor. Language disturbances might serve as a strong indicator for an underlying neurodegenerative disorder like AD. However, the current diagnostic instruments for language assessment mainly focus on product measures, such as text length or number of errors, ignoring the importance of the process that leads to written or spoken language production. In this study, it is our aim to describe and test differences between cognitive and impaired elderly on the basis of a selection of writing process variables (inter- and intrapersonal characteristics). These process variables are mainly related to pause times, because the number, length, and location of pauses have proven to be an important indicator of the cognitive complexity of a process. Method: Participants that were enrolled in our research were chosen on the basis of a number of basic criteria necessary to collect reliable writing process data. Furthermore, we opted to match the thirteen cognitively impaired patients (8 MCI and 5 AD) with thirteen cognitively healthy elderly. At the start of the experiment, participants were each given a number of tests, such as the Mini-Mental State Examination test (MMSE), the Geriatric Depression Scale (GDS), the forward and backward digit span and the Edinburgh Handedness Inventory (EHI). Also, a questionnaire was used to collect socio-demographic information (age, gender, eduction) of the subjects as well as more details on their level of computer literacy. The tests and questionnaire were followed by two typing tasks and two picture description tasks. For the typing tasks participants had to copy (type) characters, words and sentences from a screen, whereas the picture description tasks each consisted of an image they had to describe in a few sentences. Both the typing and the picture description tasks were logged with Inputlog, a keystroke logging tool that allows us to log and time stamp keystroke activity to reconstruct and describe text production processes. The main rationale behind keystroke logging is that writing fluency and flow reveal traces of the underlying cognitive processes. This explains the analytical focus on pause (length, number, distribution, location, etc.) and revision (number, type, operation, embeddedness, location, etc.) characteristics. As in speech, pause times are seen as indexical of cognitive effort. Results. Preliminary analysis already showed some promising results concerning pause times before, within and after words. For all variables, mixed effects models were used that included participants as a random effect and MMSE scores, GDS scores and word categories (such as determiners and nouns) as a fixed effect. For pause times before and after words cognitively impaired patients paused longer than healthy elderly. These variables did not show an interaction effect between the group participants (cognitively impaired or healthy elderly) belonged to and word categories. However, pause times within words did show an interaction effect, which indicates pause times within certain word categories differ significantly between patients and healthy elderly.

Keywords: Alzheimer's disease, keystroke logging, matching, writing process

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Authors: Yu-Shan Wu, Po-Liang Lai, I-Ming Chu

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Poly(methylmethacrylate)(PMMA) is the most frequently used bone void filler for vertebral augmentation in osteoporotic fracture. PMMA bone cement not only exhibits strong mechanical properties but also can fabricate according to the shape of bone defect. However, the adhesion between the PMMA-based cement and the adjacent bone is usually weak and as PMMA bone cement is inherently bioinert. The combination of bioceramics and polymers as composites may increase cell adhesion and improve biocompatibility. The nano-hydroxyapatite(HAP) not only plays a significant role in maintaining the properties of the natural bone but also offers a favorable environment for osteoconduction, protein adhesion, and osteoblast proliferation. However, defects and cracks can form at the polymer/ceramics interface, resulting in uneven distribution of stress and subsequent inferior mechanical strength. Surface-modified HAP nano-crystals were prepared by chemically grafting poly(ε-caprolactone)(PCL) on surface-modified nano-HAP surface to increase the affinity of polymer/ceramic phases .Thus, incorporation of surface-modified nano-hydroxyapatite (EC-HAP) may not only improve the interfacial adhesion between cement and bone and between nanoparticles and cement, but also increase biocompatibility. In this research, PMMA mixing with 0, 5, 10, 15, 20, 25 and 30 wt% EC-HAP were examined. MC3T3-E1 cells were used for the biological evaluation of the response to the cements in vitro. Morphology was observed using scanning electron microscopy (SEM). Mechanical properties of HAP/PMMA and EC-HAP/PMMA cement were investigated by compression test. Surface wettability of the cements was measured by contact angles.

Keywords: bone cement, biocompatibility, nano-hydroxyapatite, polycaprolactone, PMMA, surface grafting

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Authors: Mahmoud Salari

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Corruption and gender inequality are the main topics of interest for both economists and policymakers. This study develops various static and dynamic estimation models to examine the impact of gender inequality in politics and the labor market on corruption using data of 170 countries from 1998 to 2014. This study uses two most reliable corruption indexes, including Corruption Perceptions Index (CPI) and Corruption Control (CC), to evaluate corruption levels across countries. The results indicate that gender inequality in politics has a strong impact on corruption level, and those countries that have larger/smaller gender inequality in their parliaments are faced with higher/lower corruption, respectively. Meanwhile, there is no enough evidence that supports the relationship between gender inequality in the labor market and corruption, and the results indicate that gender inequality in the labor market is not directly linked to the corruption level.

Keywords: corruption, female labor force participation, politics, gender inequality

Procedia PDF Downloads 193

Authors: Mohammad Noor Hisham Osman, Ahmed Razman Abdul Latiff, Zaidi Mat Daud, Zulkarnain Muhamad Sori

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The problem that Malaysian auditors do not issue going concern opinion (GC opinion) to seriously financially distressed companies is still a pressing issue. Policy makers, particularly the Financial Statement Review Committee (FSRC) of Malaysian Institute of Accountant, have raised this issue as early as in 2009. Similar problem happened in the US, UK, and many developing countries. It is important for auditors to issue GC opinion properly because such opinion is one signal about the viability of a company much needed by stakeholders. There are at least two unanswered questions or research gaps in the literature on determinants of GC opinion. Firstly, is client’s probability of failure associated with GC opinion issuance? Secondly, to what extent influential owners (management, family, and institution) moderate the association between client probability of failure and GC opinion issuance. The objective of this study is, therefore, twofold; (1) To examine the extent of the relationship between the probability of client failure and the issuance of GC opinion and (2) To examine the level of management, family, and institutional ownerships moderate the association between client probability of failure and the issuance of GC opinion. This study is quantitative in nature, and the sources of data are secondary (mainly company’s annual reports). A total of four hypotheses have been developed and tested on data accumulated from annual reports of seriously financially distressed Malaysian public listed companies. Data from 2006 to 2012 on a sample of 644 observations have been analyzed using panel logistic regression. It is found that certainty (rather than probability) of client failure affects the issuance of GC opinion. In addition, it is found that only the level of family ownership does positively moderate the relationship between client probability of failure and GC opinion issuance. This study is a contribution to auditing literature as its findings can enhance our understanding about audit quality; particularly on the variables that are associated with the issuance of GC opinion. The findings of this study shed light on the roles family owners in GC opinion issuance process, and this would open ways for the researcher to suggest measures that can be used to tackle the problem of auditors do not want to issue GC opinion to financially distressed clients. The measures to be suggested can be useful to policy makers in formulating future promulgations.

Keywords: audit quality, auditing, auditor characteristics, going concern opinion, Malaysia

Procedia PDF Downloads 262

Authors: Felipa de Mello-Sampayo

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The aim of this study is to undertake, from patient’s perspective, the timing and probability of using teledermatology, comparing it with a conventional referral system. The dynamic stochastic model’s main value-added consists of the concrete application to patients waiting for dermatology surgical intervention. Patients with low health level uncertainty must use teledermatology treatment as soon as possible, which is precisely when the teledermatology is least valuable. The results of the model were then tested empirically with the teledermatology network covering the area served by the Hospital Garcia da Horta, Portugal, links the primary care centers of 24 health districts with the hospital’s dermatology department via the corporate intranet of the Portuguese healthcare system. Health level volatility can be understood as the hazard of developing skin cancer and the trend of health level as the bias of developing skin lesions. The results of the survival analysis suggest that the theoretical model can explain the use of teledermatology. It depends negatively on the volatility of patients' health, and positively on the trend of health, i.e., the lower the risk of developing skin cancer and the younger the patients, the more presurgical teledermatology one expects to occur. Presurgical teledermatology also depends positively on out-of-pocket expenses and negatively on the opportunity costs of teledermatology, i.e., the lower the benefit missed by using teledermatology, the more presurgical teledermatology one expects to occur.

Keywords: teledermatology, wait time, uncertainty, opportunity cost, survival analysis

Procedia PDF Downloads 132

Authors: J. Joy, T. H. New, I. H. Ibrahim

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A computational study on bio-inspired NACA634-021 hydrofoils with leading-edge protuberances has been carried out to investigate their hydrodynamic flow control characteristics at a Reynolds number of 14,000 and different angles-of-attack. The numerical simulations were performed using ANSYS FLUENT and based on Reynolds-Averaged Navier-Stokes (RANS) solver mode incorporated with k-ω Shear Stress Transport (SST) turbulence model. The results obtained indicate varying flow phenomenon along the peaks and troughs over the span of the hydrofoils. Compared to the baseline hydrofoil with no leading-edge protuberances, the leading-edge modified hydrofoils tend to reduce flow separation extents along the peak regions. In contrast, there are increased flow separations in the trough regions of the hydrofoil with leading-edge protuberances. Interestingly, it was observed that dissimilar flow separation behaviour is produced along different peak- or trough-planes along the hydrofoil span, even though the troughs or peaks are physically similar at each interval for a particular hydrofoil. Significant interactions between adjacent flow structures produced by the leading-edge protuberances have also been observed. These flow interactions are believed to be responsible for the dissimilar flow separation behaviour along physically similar peak- or trough-planes.

Keywords: computational fluid dynamics, flow separation control, hydrofoils, leading-edge protuberances

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Authors: Rupinder Kaur, Harjot Kaur

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The objective of this paper is to present the study of the effect of varying thickness on rotating composite disks made from Al-SiC_P having different particle sizes. Mathematical modeling is used to calculate the effect of varying thickness with different particle sizes on rotating composite disks in radial as well as tangential directions with thermal gradients. In comparison to various particle sizes with varied thicknesses, long-term deformation occurs. The results are displayed visually, demonstrating how creep deformation decreases with changing particle size and thickness.

Keywords: creep, varying thickness, particle size, stresses and strain rates

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Authors: Ntalamagka N., Sanchis-Benlloch P. J., Mayoral-Serrano R., Tena-Medialdea J., García-March J. R.

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The pen shell Pinna nobilis population has declined dramatically since 2016 due to die-off events observed in the whole extent of the Mediterranean Sea associated with the protozoan Haplosporidium pinnae. As of 2019, it is considered a critically endangered species. Due to its ecological importance and its endangered status, several initiatives have been developed for its salvation and recovery. This research is an effort to understand and control its reproduction under captivity. As a limited number of Pinna nobilis individuals could be used for experimentation, the possibility of using the Pinna rudis as a model animal was explored. The molecular mechanism that regulates the reproduction of both species is unknown; consequently, transcriptomic analysis was performed to identify neuropeptides that are expressed in the key regulatory tissues of the visceral ganglia and gonads of both species. Neuropeptides form an important group of signaling peptides that regulate reproductive, behavioral and physiological functions in molluscs. In total, 17 neuropeptide precursors were identified in P. nobilis and 14 in P. rudis transcriptomes; 14 of them were identical in both species. This affinity verified the genetic similarity of these species at the reproduction level. APGWamide, buccalin, ELH and GnRH were tested in P. rudis and demonstrated their capacity to advance gonadal maturation and trigger spawning while spawning was recorded in P. nobilis after the usage of APGWamide and buccalin. The neuropeptides were administered using intramuscular injection and cholesterol implants following relative literature as well as a new method was developed for external administration without the use of anesthesia using a mathematical model. The know-how of this research will not only lead to the survival of the species but also will narrow the horizons of broodstock conditioning of other similar species.

Keywords: neuropeptides, Pinna nobilis, reproduction, transcriptomics

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Authors: Yousaf Tariq

Abstract:

There are many reasons which are involved in electronic equipment failure i.e. temperature, humidity, dust, smoke etc. Corrosive gases are also one of the factor which may involve in failure of equipment. Sensitivity of electronic equipment increased when “lead-free” regulation enforced on manufacturers. In data center, equipment like hard disk, servers, printed circuit boards etc. have been exposed to gaseous contamination due to increase in sensitivity. There is a worldwide standard to protect electronic industrial electronic from corrosive gases. It is well known as “ANSI/ISA S71.04 – 1985 - Environmental Conditions for Control Systems: Airborne Contaminants. ASHRAE Technical Committee (TC) 9.9 members also recommended ISA standard in their whitepaper on Gaseous and Particulate Contamination Guideline for data centers. TC 9.9 members represented some of the major IT equipment manufacturers e.g. IBM, HP, Cisco etc. As per standard practices, first step is to monitor air quality in data center. If contamination level shows more than G1, it means that gas-phase air filtration is required other than dust/smoke air filtration. It is important that outside fresh air entering in data center should have pressurization/re-circulated process in order to absorb corrosive gases and to maintain level within specified limit. It is also important that air quality monitoring should be conducted once in a year. Temperature and humidity should also be monitored as per standard practices to maintain level within specified limit.

Keywords: corrosive gases, corrosion, electronic equipment failure, ASHRAE, hard disk

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Authors: Zhiyuan Du, Baisravan Hom Chaudhuri, Pierluigi Pisu

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In connected vehicle systems where wireless communication is available among the involved vehicles and intersection controllers, it is possible to design an intersection coordination strategy that leads the connected and automated vehicles (CAVs) travel through the road intersections without the conventional traffic light control. In this paper, we present a distributed coordination strategy for the CAVs at multiple interconnected intersections that aims at improving system fuel efficiency and system mobility. We present a distributed control solution where in the higher level, the intersection controllers calculate the road desired average velocity and optimally assign reference velocities of each vehicle. In the lower level, every vehicle is considered to use model predictive control (MPC) to track their reference velocity obtained from the higher level controller. The proposed method has been implemented on a simulation-based case with two-interconnected intersection network. Additionally, the effects of mixed vehicle types on the coordination strategy has been explored. Simulation results indicate the improvement on vehicle fuel efficiency and traffic mobility of the proposed method.

Keywords: connected vehicles, automated vehicles, intersection coordination systems, multiple interconnected intersections, model predictive control

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Authors: Vaishnavi Unde, Srikanth Mutnuri

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Today dye stuff sector is one of the major chemical industries in India. Indigo is a blue coloured dye used all over the world in large quantity. The indigo dye produced and used in textile industries is synthetic having toxic effect, thus there is an increase in interest for natural dyes owing to the environmental concerns. The present study focuses on the use of a strain Pandoraea sp. isolated from garage soil, for the production of indigo in fed batch bioreactor. A comparative study between single phase and two phase production was carried out in this work. The blue colour produced during the experiments was analyzed using, TLC, UV-visible spectrophotometer and FTIR technique. The blue pigment was found to be indigo. The production of bio-indigo was done in a single phase fermentor carrying medium and substrate indole in dissolved form and was found to produce maximum of 0.041 g/L of indigo. Whereas there was an increase in production of indigo to 0.068 g/L in a two phase, water-silicone oil system. In this study the advantage of using second phase as silicone oil has enhanced the indigo production, as the second phase made the substrate available to the bacteria by increasing the surface area as well as it helped to prevent the inhibition effect of the high concentration of substrate, indole. The effect of single and two phases on the growth of bacteria was also studied.

Keywords: dyes, fed batch reactor, indole, Indigo

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Authors: E. Ruíz, W. Aperador

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In this article evaluates the protective effect of the concrete alternative obtained from the fly ash and iron and steel slag mixed in binary form and were placed on structural steel ASTM A 706. The study was conducted comparatively with specimens exposed to natural conditions free of chloride ion. The effect of chloride ion on the specimens was generated of form accelerated under controlled conditions (3.5% NaCl and 25 ° C temperature). The Impedance data were acquired over a range of 1 mHz to 100 kHz. At frequencies high is found the response of the interface means of the exposure-concrete and to frequency low the response of the interface corresponding to concrete-steel.

Keywords: alternative concrete, corrosion, alkaline activation, impedance spectroscopy

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Authors: Jeremy Ritchey

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Undocumented immigrants in the U.S. face many challenges when looking to progress in society, especially when pursuing post-secondary education. The majority of research done on state-level policy adoption pertaining to undocumented higher-education pursuits, specifically in-state resident tuition and financial aid eligibility policies, have framed the discussion on the potential and actual impacts which implementation can and has achieved. What is missing is a model to view the social, political and demographic landscapes upon which such policies (in their various forms) find a route to legislative enactment. This research looks to address this gap in the field by investigating the correlations and significant state-level variables which can be operationalized to construct a framework for adoption of these specific policies. In the process, analysis will show that past unexamined conceptualizations of how such policies come to fruition may be limited or contradictory when compared to available data. Circling on the principles of Policy Innovation and Policy Diffusion theory, this study looks to use variables collected via Michigan State University’s Correlates of State Policy Project, a collectively and ongoing compiled database project centered around annual variables (1900-2016) collected from all 50 states relevant to policy research. Using established variable groupings (demographic, political, social capital measurements, and educational system measurements) from the time period of 2000 to 2014 (2001 being when such policies began), one can see how this data correlates with the adoption of policies related to undocumented students and in-state college tuition. After regression analysis, the results will illuminate which variables appears significant and to what effect, as to help formulate a model upon which to explain when adoption appears to occur and when it does not. Early results have shown that traditionally held conceptions on conservative and liberal identities of the state, as they relate to the likelihood of such policies being adopted, did not fall in line with the collected data. Democratic and liberally identified states were, overall, less likely to adopt pro-undocumented higher education policies than Republican and conservatively identified states and vis versa. While further analysis is needed as to improve the model’s explanatory power, preliminary findings are showing promise in widening our understanding of policy adoption factors in this realm of policies compared to the gap of such knowledge in the publications of the field as it currently exists. The model also looks to serve as an important tool for policymakers in framing such potential policies in a way that is congruent with the relevant state-level determining factors while being sensitive to the most apparent sources of potential friction. While additional variable groups and individual variables will ultimately need to be added and controlled for, this research has already begun to demonstrate how shallow or unexamined reasoning behind policy adoption in the realm of this topic needs to be addressed or else the risk is erroneous conceptions leaking into the foundation of this growing and ever important field.

Keywords: policy adoption, in-state tuition, higher education, undocumented immigrants

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Authors: Andreas Schomburg, Claire Le Bayon, Claire Guenat, Philip Brunner

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Numerous river restoration projects have been established in Switzerland in recent years after decades of human activity in floodplains. The success of restoration projects in terms of biodiversity and ecosystem functions largely depend on the development of the floodplain soil system. Plants and earthworms as ecosystem engineers are known to be able to build up a stable soil structure by incorporating soil organic matter into the soil matrix that creates water stable soil aggregates. Their engineering efficiency however largely depends on changing soil properties and frequent floods along an evolutive floodplain transect. This study, therefore, aims to quantify the effect of flood frequency and duration as well as of physico-chemical soil parameters on plants’ and earthworms’ engineering efficiency. It is furthermore predicted that these influences may have a different impact on one of the engineers that leads to a varying contribution to aggregate formation within the floodplain transect. Ecosystem engineers were sampled and described in three different floodplain habitats differentiated according to the evolutionary stages of the vegetation ranging from pioneer to forest vegetation in a floodplain restored 15 years ago. In addition, the same analyses were performed in an embanked adjacent pasture as a reference for the pre-restored state. Soil aggregates were collected and analyzed for their organic matter quantity and quality using Rock Eval pyrolysis. Water level and discharge measurements dating back until 2008 were used to quantify the return period of major floods. Our results show an increasing amount of water stable aggregates in soil with increasing distance to the river and show largest values in the reference site. A decreasing flood frequency and the proportion of silt and clay in the soil texture explain these findings according to F values from one way ANOVA of a fitted mixed effect model. Significantly larger amounts of labile organic matter signatures were found in soil aggregates in the forest habitat and in the reference site that indicates a larger contribution of plants to soil aggregation in these habitats compared to the pioneer vegetation zone. Earthworms’ contribution to soil aggregation does not show significant differences in the floodplain transect, but their effect could be identified even in the pioneer vegetation with its large proportion of coarse sand in the soil texture and frequent inundations. These findings indicate that ecosystem engineers seem to be able to create soil aggregates even under unfavorable soil conditions and under frequent floods. A restoration success can therefore be expected even in ecosystems with harsh soil properties and frequent external disturbances.

Keywords: ecosystem engineers, flood frequency, floodplains, river restoration, rock eval pyrolysis, soil organic matter incorporation, soil structuration

Procedia PDF Downloads 273