Search results for: Reader response theory
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9870

Search results for: Reader response theory

2730 The Patterns of Cross-Sentence: An Event-Related Potential Study of Mathematical Word Problem

Authors: Tien-Ching Yao, Ching-Ching Lu

Abstract:

Understanding human language processing is one of the main challenges of current cognitive neuroscience. The aims of the present study were to use a sentence decision task combined with event-related potentials to investigate the psychological reality of "cross-sentence patterns." Therefore, we take the math word problems the experimental materials and use the ERPs' P600 component to verify. In this study, the experimental material consisted of 200 math word problems with three different conditions were used ( multiplication word problems、division word problems type 1、division word problems type 2 ). Eighteen Mandarin native speakers participated in the ERPs study (14 of whom were female). The result of the grand average waveforms suggests a later posterior positivity at around 500ms - 900ms. These findings were tested statistically using repeated measures ANOVAs at the component caused by the stimulus type of different questions. Results suggest that three conditions present significant (P < 0.05) on the Mean Amplitude, Latency, and Peak Amplitude. The result showed the characteristic timing and posterior scalp distribution of a P600 effect. We interpreted these characteristic responses as the psychological reality of "cross-sentence patterns." These results provide insights into the sentence processing issues in linguistic theory and psycholinguistic models of language processing and advance our understanding of how people make sense of information during language comprehension.

Keywords: language processing, sentence comprehension, event-related potentials, cross-sentence patterns

Procedia PDF Downloads 152
2729 Analysis of Factors Affecting the Number of Infant and Maternal Mortality in East Java with Geographically Weighted Bivariate Generalized Poisson Regression Method

Authors: Luh Eka Suryani, Purhadi

Abstract:

Poisson regression is a non-linear regression model with response variable in the form of count data that follows Poisson distribution. Modeling for a pair of count data that show high correlation can be analyzed by Poisson Bivariate Regression. Data, the number of infant mortality and maternal mortality, are count data that can be analyzed by Poisson Bivariate Regression. The Poisson regression assumption is an equidispersion where the mean and variance values are equal. However, the actual count data has a variance value which can be greater or less than the mean value (overdispersion and underdispersion). Violations of this assumption can be overcome by applying Generalized Poisson Regression. Characteristics of each regency can affect the number of cases occurred. This issue can be overcome by spatial analysis called geographically weighted regression. This study analyzes the number of infant mortality and maternal mortality based on conditions in East Java in 2016 using Geographically Weighted Bivariate Generalized Poisson Regression (GWBGPR) method. Modeling is done with adaptive bisquare Kernel weighting which produces 3 regency groups based on infant mortality rate and 5 regency groups based on maternal mortality rate. Variables that significantly influence the number of infant and maternal mortality are the percentages of pregnant women visit health workers at least 4 times during pregnancy, pregnant women get Fe3 tablets, obstetric complication handled, clean household and healthy behavior, and married women with the first marriage age under 18 years.

Keywords: adaptive bisquare kernel, GWBGPR, infant mortality, maternal mortality, overdispersion

Procedia PDF Downloads 164
2728 Photocatalytic Hydrogen Production, Effect of Metal Particle Size and Their Electronic/Optical Properties on the Reaction

Authors: Hicham Idriss

Abstract:

Hydrogen production from water is one of the most promising methods to secure renewable sources or vectors of energy for societies in general and for chemical industries in particular. At present over 90% of the total amount of hydrogen produced in the world is made from non-renewable fossil fuels (via methane reforming). There are many methods for producing hydrogen from water and these include reducible oxide materials (solar thermal production), combined PV/electrolysis, artificial photosynthesis and photocatalysis. The most promising of these processes is the one relying on photocatalysis; yet serious challenges are hindering its success so far. In order to make this process viable considerable improvement of the photon conversion is needed. Among the key studies that our group has been conducting in the last few years are those focusing on synergism between the semiconductor phases, photonic band gap materials, pn junctions, plasmonic resonance responses, charge transfer to metal cations, in addition to metal dispersion and band gap engineering. In this work results related to phase transformation of the anatase to rutile in the case of TiO2 (synergism), of Au and Ag dispersion (electron trapping and hydrogen-hydrogen recombination centers) as well as their plasmon resonance response (visible light conversion) are presented and discussed. It is found for example that synergism between the two common phases of TiO2 (anatase and rutile) is sensitive to the initial particle size. It is also found, in agreement with previous results, that the rate is very sensitive to the amount of metals (with similar particle size) on the surface unlike the case of thermal heterogeneous catalysis.

Keywords: photo-catalysis, hydrogen production, water splitting, plasmonic

Procedia PDF Downloads 256
2727 Aesthetic Preference and Consciousness in African Theatre: A Performance Appraisal of Tyrone Terrence's a Husband's Wife

Authors: Oluwatayo Isijola

Abstract:

The destructive influence of Europe on Africa has also taken a tow on the aesthetic essence of the African Art, which centres on morality and value for human life. In a parallel vein, the adverse turn of this influence on the dramaturgy of some contemporary African plays, poses impedance to audience consciousness in performance engagements. Through the spectrum of African Aesthetics, this study attempts a performance appraisal of A Husband’s wife; an unpublished play written by Tyrone Terence for the African audience. The researcher proffers two variant textual interpretations of the play to evaluate performance engagement in its default realistic mode, which holds an unresolved 'Medean-impulse', and another wherein the resolution is treated to a paradigm shift for aesthetic preference. The investigation employs the mixed method, which combines the quantitative and qualitative methodologies. Keen observation on the reactions and responses of audience members that were engaged in both performances, and on-the-spot interview with selected audience members, were the primary sources for the qualitative data. However, quantitative data was captured in an on-the-spot survey with the instrument of the questionnaire served to a sample population of the audience. The study observes that the preference for African aesthetics as exemplified in the second performance which deployed a paradigm shift did enhance audience consciousness. Hinging on performance aesthetic theory, the paper recommends that all such African plays bestowed with the shortcoming of African aesthetics, should be appropriately treated to paradigm shifts for performance engagement, in the interest of enhancing audience consciousness in the Nigerian Theatre.

Keywords: African aesthetics, audience consciousness, paradigm shift, median-impulse

Procedia PDF Downloads 336
2726 The Use of the Limit Cycles of Dynamic Systems for Formation of Program Trajectories of Points Feet of the Anthropomorphous Robot

Authors: A. S. Gorobtsov, A. S. Polyanina, A. E. Andreev

Abstract:

The movement of points feet of the anthropomorphous robot in space occurs along some stable trajectory of a known form. A large number of modifications to the methods of control of biped robots indicate the fundamental complexity of the problem of stability of the program trajectory and, consequently, the stability of the control for the deviation for this trajectory. Existing gait generators use piecewise interpolation of program trajectories. This leads to jumps in the acceleration at the boundaries of sites. Another interpolation can be realized using differential equations with fractional derivatives. In work, the approach to synthesis of generators of program trajectories is considered. The resulting system of nonlinear differential equations describes a smooth trajectory of movement having rectilinear sites. The method is based on the theory of an asymptotic stability of invariant sets. The stability of such systems in the area of localization of oscillatory processes is investigated. The boundary of the area is a bounded closed surface. In the corresponding subspaces of the oscillatory circuits, the resulting stable limit cycles are curves having rectilinear sites. The solution of the problem is carried out by means of synthesis of a set of the continuous smooth controls with feedback. The necessary geometry of closed trajectories of movement is obtained due to the introduction of high-order nonlinearities in the control of stabilization systems. The offered method was used for the generation of trajectories of movement of point’s feet of the anthropomorphous robot. The synthesis of the robot's program movement was carried out by means of the inverse method.

Keywords: control, limits cycle, robot, stability

Procedia PDF Downloads 332
2725 A Visual Analytics Tool for the Structural Health Monitoring of an Aircraft Panel

Authors: F. M. Pisano, M. Ciminello

Abstract:

Aerospace, mechanical, and civil engineering infrastructures can take advantages from damage detection and identification strategies in terms of maintenance cost reduction and operational life improvements, as well for safety scopes. The challenge is to detect so called “barely visible impact damage” (BVID), due to low/medium energy impacts, that can progressively compromise the structure integrity. The occurrence of any local change in material properties, that can degrade the structure performance, is to be monitored using so called Structural Health Monitoring (SHM) systems, in charge of comparing the structure states before and after damage occurs. SHM seeks for any "anomalous" response collected by means of sensor networks and then analyzed using appropriate algorithms. Independently of the specific analysis approach adopted for structural damage detection and localization, textual reports, tables and graphs describing possible outlier coordinates and damage severity are usually provided as artifacts to be elaborated for information extraction about the current health conditions of the structure under investigation. Visual Analytics can support the processing of monitored measurements offering data navigation and exploration tools leveraging the native human capabilities of understanding images faster than texts and tables. Herein, a SHM system enrichment by integration of a Visual Analytics component is investigated. Analytical dashboards have been created by combining worksheets, so that a useful Visual Analytics tool is provided to structural analysts for exploring the structure health conditions examined by a Principal Component Analysis based algorithm.

Keywords: interactive dashboards, optical fibers, structural health monitoring, visual analytics

Procedia PDF Downloads 127
2724 Classic Modelled Hybrid Electric Vehicles Using The Power of Internet Of Things

Authors: Venkatesh Krishna Murthy

Abstract:

The era before government-regulated automotive designs gave us some astonishing vehicles that are well worth to keep on the road. The fact that restoring an automobile in 2015 does not mean it will perform like one designed in 2021. This is one of the reasons that manufacturers continue to turn to vintage hardware for future enhancements in their vehicles. Now we need to understand that a modern chassis could possibly allow manufacturers to give vintage performance cars a level of braking capability, compatibility with tires, chassis rigidity, suspension sophistication, and steering response, an experience only racers got until now. However, half a century of advancements in engineering can have a great impact on design in any field, and the automotive realm which holds no exception. In the current situation, a growing number of companies offer chassis and braking components to onboard manufacturers to retrofit contemporary technology for their vintage vehicles to modernize them at the foundation level. The recent question arises on performance on lithium batteries, as opposed to simply bolting upgraded components, for ex. lithium batteries with graphene as superconductive material to enhance performance, an area deeply investigated. Serving as the “bones” of the vehicle, the chassis and frame play a central role in dictating how that automobile will perform. While the desire to maintain originality is alluring for many, the benefits of a modern chassis are vast. In some situations, it also allows builders to put cars back on the road that might otherwise be too far gone. “There’s a couple of different factors at play here – one of them being that these older cars from the ’40s, ’50s, and ’60s have seen a lot of weather and a lot of road miles over the years, more often than not,” says Craig Morrison of Art Morrison Enterprises.

Keywords: hybrid electric vehicles, internet of things, lithium graphene batteries, classic car chassis

Procedia PDF Downloads 175
2723 Graphene Based Materials as Novel Membranes for Water Desalination and Boron Separation

Authors: Francesca Risplendi, Li-Chiang Lin, Jeffrey C. Grossman, Giancarlo Cicero

Abstract:

Desalination is one of the most employed approaches to supply water in the context of a rapidly growing global water shortage. However, the most popular water filtration method available is the reverse osmosis (RO) technique, still suffers from important drawbacks, such as a large energy demands and high process costs. In addition some serious limitations have been recently discovered, among them, the boron problem seems to have a critical meaning. Boron has been found to have a dual effect on the living systems on Earth and the difference between boron deficiency and boron toxicity levels is quite small. The aim of this project is to develop a new generation of RO membranes based on porous graphene or reduced graphene oxide (rGO) able to remove salts from seawater and to reduce boron concentrations in the permeate to the level that meets the drinking or process water requirements, by means of a theoretical approach based on density functional theory and classical molecular dynamics. Computer simulations have been employed to investigate the relationship between the atomic structure of nanoporous graphene or rGO monolayer and its membrane properties in RO applications (i.e. water permeability and resilience at RO pressures). In addition, an emphasis has been given to multilayer nanoporous rGO and rGO flakes based membranes. By means of non-equilibrium MD simulations, we investigated the water transport mechanism permeating through such multilayer membrane focusing on the effect of slit widths and sheet geometries. These simulations allowed us to establish the implications of these graphene based materials as promising membrane properties for desalination plants and as boron filtration.

Keywords: boron filtration, desalination, graphene membrane, reduced graphene oxide membrane

Procedia PDF Downloads 302
2722 Grassland Phenology in Different Eco-Geographic Regions over the Tibetan Plateau

Authors: Jiahua Zhang, Qing Chang, Fengmei Yao

Abstract:

Studying on the response of vegetation phenology to climate change at different temporal and spatial scales is important for understanding and predicting future terrestrial ecosystem dynamics andthe adaptation of ecosystems to global change. In this study, the Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) dataset and climate data were used to analyze the dynamics of grassland phenology as well as their correlation with climatic factors in different eco-geographic regions and elevation units across the Tibetan Plateau. The results showed that during 2003–2012, the start of the grassland greening season (SOS) appeared later while the end of the growing season (EOS) appeared earlier following the plateau’s precipitation and heat gradients from southeast to northwest. The multi-year mean value of SOS showed differences between various eco-geographic regions and was significantly impacted by average elevation and regional average precipitation during spring. Regional mean differences for EOS were mainly regulated by mean temperature during autumn. Changes in trends of SOS in the central and eastern eco-geographic regions were coupled to the mean temperature during spring, advancing by about 7d/°C. However, in the two southwestern eco-geographic regions, SOS was delayed significantly due to the impact of spring precipitation. The results also showed that the SOS occurred later with increasing elevation, as expected, with a delay rate of 0.66 d/100m. For 2003–2012, SOS showed an advancing trend in low-elevation areas, but a delayed trend in high-elevation areas, while EOS was delayed in low-elevation areas, but advanced in high-elevation areas. Grassland SOS and EOS changes may be influenced by a variety of other environmental factors in each eco-geographic region.

Keywords: grassland, phenology, MODIS, eco-geographic regions, elevation, climatic factors, Tibetan Plateau

Procedia PDF Downloads 323
2721 Virtual Reality as a Method in Transformative Learning: A Strategy to Reduce Implicit Bias

Authors: Cory A. Logston

Abstract:

It is imperative researchers continue to explore every transformative strategy to increase empathy and awareness of racial bias. Racism is a social and political concept that uses stereotypical ideology to highlight racial inequities. Everyone has biases they may not be aware of toward disparate out-groups. There is some form of racism in every profession; doctors, lawyers, and teachers are not immune. There have been numerous successful and unsuccessful strategies to motivate and transform an individual’s unconscious biased attitudes. One method designed to induce a transformative experience and identify implicit bias is virtual reality (VR). VR is a technology designed to transport the user to a three-dimensional environment. In a virtual reality simulation, the viewer is immersed in a realistic interactive video taking on the perspective of a Black man. The viewer as the character experiences discrimination in various life circumstances growing up as a child into adulthood. For instance, the prejudice felt in school, as an adolescent encountering the police and false accusations in the workplace. Current research suggests that an immersive VR simulation can enhance self-awareness and become a transformative learning experience. This study uses virtual reality immersion and transformative learning theory to create empathy and identify any unintentional racial bias. Participants, White teachers, will experience a VR immersion to create awareness and identify implicit biases regarding Black students. The desired outcome provides a springboard to reconceptualize their own implicit bias. Virtual reality is gaining traction in the research world and promises to be an effective tool in the transformative learning process.

Keywords: empathy, implicit bias, transformative learning, virtual reality

Procedia PDF Downloads 203
2720 Bifurcations of a System of Rotor-Ball Bearings with Waviness and Squeeze Film Dampers

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

Abstract:

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

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

Procedia PDF Downloads 386
2719 How Envisioning Process Is Constructed: An Exploratory Research Comparing Three International Public Televisions

Authors: Alexandre Bedard, Johane Brunet, Wendellyn Reid

Abstract:

Public Television is constantly trying to maintain and develop its audience. And to achieve those goals, it needs a strong and clear vision. Vision or envision is a multidimensional process; it is simultaneously a conduit that orients and fixes the future, an idea that comes before the strategy and a mean by which action is accomplished, from a business perspective. Also, vision is often studied from a prescriptive and instrumental manner. Based on our understanding of the literature, we were able to explain how envisioning, as a process, is a creative one; it takes place in the mind and uses wisdom and intelligence through a process of evaluation, analysis and creation. Through an aggregation of the literature, we build a model of the envisioning process, based on past experiences, perceptions and knowledge and influenced by the context, being the individual, the organization and the environment. With exploratory research in which vision was deciphered through the discourse, through a qualitative and abductive approach and a grounded theory perspective, we explored three extreme cases, with eighteen interviews with experts, leaders, politicians, actors of the industry, etc. and more than twenty hours of interviews in three different countries. We compared the strategy, the business model, and the political and legal forces. We also looked at the history of each industry from an inertial point of view. Our analysis of the data revealed that a legitimacy effect due to the audience, the innovation and the creativity of the institutions was at the cornerstone of what would influence the envisioning process. This allowed us to identify how different the process was for Canadian, French and UK public broadcasters, although we concluded that the three of them had a socially constructed vision for their future, based on stakeholder management and an emerging role for the managers: ideas brokers.

Keywords: envisioning process, international comparison, television, vision

Procedia PDF Downloads 137
2718 Receptiveness of Market Segmentation Towards Online Shopping Attitude: A Quality Management Strategy for Online Passenger Car Market

Authors: Noor Hasmini Abdghani, Nik Kamariah Nikmat, Nor Hayati Ahmad

Abstract:

Rapid growth of the internet technology led to changes in the consumer lifestyles. This involved customer buying behaviour-based internet that create new kind of buying strategy. Hence, it has summoned many of world firms including Malaysia to generate new quality strategy in preparation to face new customer buying lifestyles. Particularly, this study focused on identifying online customer segment of automobile passenger car customers. Secondly, the objective is to understand online customer’s receptiveness towards internet technologies. This study distributed 700 questionnaires whereby 582 were returned representing 83% response rate. The data were analysed using factor and regression analyses. The result from the factor analysis precipitates four online passenger car segmentations in Malaysia, which are: Segment (1)- Automobile Online shopping Preferences, Segment (2)- Automobile Online Brand Comparison, Segment (3)- Automobile Online Information Seeking and Segment (4)- Automobile Offline Shopping Preferences. In understanding the online customer’s receptiveness towards internet, the regression result shows that there is significant relationship between each of four segments of online passenger car customer with attitude towards automobile online shopping. This implies that, for online customers to have receptiveness toward internet technologies, he or she must have preferences toward online shopping or at least prefer to browse any related information online even if the actual purchase is made at the traditional store. With this proposed segmentation strategy, the firms especially the automobile firms will be able to understand their online customer behavior. At least, the proposed segmentation strategy will help the firms to strategize quality management approach for their online customers’ buying decision making.

Keywords: Automobile, Market Segmentation, Online Shopping Attitude, Quality Management Strategy

Procedia PDF Downloads 542
2717 Perceived Physical Exercise Benefits among Staff of Tertiary Institutions in Adamawa State

Authors: Salihu Mohammed Umar

Abstract:

Perceived physical exercise benefits among staff of tertiary institutions in Adamawa State was investigated as a basis for formulating proper exercise intervention strategies. The study utilized descriptive survey design. The purpose of the study was to determine perceived exercise benefits among staff of tertiary institutions in Adamawa state, Nigeria. The instrument used for data collection was a questionnaire adapted from Exercise Benefit/Barrier Scale (EBBS) developed by Sechrist, Walker and Pender (1985) which was validated by five experts. Three hundred and thirty (330) copies of the questionnaire were distributed among study participants in six institutions of higher learning in Adamawa state. The scale comprised two components; Benefits and Barriers dimensions. To achieve this purpose, three research questions were posed. The instrument had a four response forced-choice Likert-type format with responses ranging from 4 = strongly agree (SA), 3 = Agree (A), 2 = Disagree (D) and 1 = Strongly Disagree (SD). The findings of the study revealed that both male and female staff in institutions of higher learning in Adamawa state perceived exercise as highly beneficial. However, male staff had higher perceived benefits score than their female counterparts. (Male: x̄ = 95.02. SD = 3.08) > female: x̄ = 94.04, SD = 4.35. There was also no significant difference in perceived exercise barriers between staff and students of tertiary institutions in Adamawa state. Based on the finding of the study, it was concluded that staff of tertiary institutions perceived exercise as highly beneficial. It was recommended that since staff of institutions of higher learning in Adamawa State irrespective of gender and religious affiliations have basic knowledge of perceived benefits of exercise, there is the need to explore programmes that will enable staff across the sub-groups to overcome barriers that could discourage physical exercise participation.

Keywords: perception, physical exercise, staff, benefits

Procedia PDF Downloads 319
2716 Comparison of Transforming Growth Factor-β1 Levels in the Human Gingival Sulcus during Canine Retraction Using Elastic Chain and Closed Coil Spring

Authors: Sri Suparwitri

Abstract:

When an orthodontic force is applied to a tooth, an inflammatory response is initiated then lead to bone remodeling process, and the process accommodates tooth movement. One of cytokine that plays a prominent role in bone remodeling process was transforming growth factor-beta 1 (TGF-β1). The purpose of this study was to identify and compare changes of TGF-β1 in human gingival crevicular fluid during canine retraction using elastic chain and closed coil spring. Ten patients (mean age 20.7 ± 2.9 years) participated. The patients were entering the space closure phase of fixed orthodontic treatment. An upper canine of each patient was retracted using elastic chain, and the contralateral canine was retracted using closed coil spring. Gingival crevicular fluid samples were collected from the canine teeth before and 7 days after the force was applied. Transforming growth factor-beta 1 was determined by enzyme-linked immunosorbent assay (ELISA). The concentrations of TGF-β1 at 7 days were significantly higher compared to before canine retraction in both groups. In the evaluation of between-group difference, before retraction, the difference was insignificant, whereas at 7 days significantly higher values were determined in the closed coil spring group compared to elastic chain group. The result suggests that TGF-β1 is associated with the bone remodeling that occurs during canine distalization movement. Closed coil spring gave higher TGF-β1 concentrations thus more bone remodeling occurred and may be considered the treatment of choice.

Keywords: closed coil spring, elastic chain, gingival crevicular fluid, TGF-β1

Procedia PDF Downloads 175
2715 Opto-Electronic Properties and Structural Phase Transition of Filled-Tetrahedral NaZnAs

Authors: R. Khenata, T. Djied, R. Ahmed, H. Baltache, S. Bin-Omran, A. Bouhemadou

Abstract:

We predict structural, phase transition as well as opto-electronic properties of the filled-tetrahedral (Nowotny-Juza) NaZnAs compound in this study. Calculations are carried out by employing the full potential (FP) linearized augmented plane wave (LAPW) plus local orbitals (lo) scheme developed within the structure of density functional theory (DFT). Exchange-correlation energy/potential (EXC/VXC) functional is treated using Perdew-Burke and Ernzerhof (PBE) parameterization for generalized gradient approximation (GGA). In addition to Trans-Blaha (TB) modified Becke-Johnson (mBJ) potential is incorporated to get better precision for optoelectronic properties. Geometry optimization is carried out to obtain the reliable results of the total energy as well as other structural parameters for each phase of NaZnAs compound. Order of the structural transitions as a function of pressure is found as: Cu2Sb type → β → α phase in our study. Our calculated electronic energy band structures for all structural phases at the level of PBE-GGA as well as mBJ potential point out; NaZnAs compound is a direct (Γ–Γ) band gap semiconductor material. However, as compared to PBE-GGA, mBJ potential approximation reproduces higher values of fundamental band gap. Regarding the optical properties, calculations of real and imaginary parts of the dielectric function, refractive index, reflectivity coefficient, absorption coefficient and energy loss-function spectra are performed over a photon energy ranging from 0.0 to 30.0 eV by polarizing incident radiation in parallel to both [100] and [001] crystalline directions.

Keywords: NaZnAs, FP-LAPW+lo, structural properties, phase transition, electronic band-structure, optical properties

Procedia PDF Downloads 437
2714 Analysis of Spatiotemporal Efficiency and Fairness of Railway Passenger Transport Network Based on Space Syntax: Taking Yangtze River Delta as an Example

Authors: Lin Dong, Fei Shi

Abstract:

Based on the railway network and the principles of space syntax, the study attempts to reconstruct the spatial relationship of the passenger network connections from space and time perspective. According to the travel time data of main stations in the Yangtze River Delta urban agglomeration obtained by the Internet, the topological drawing of railway network under different time sections is constructed. With the comprehensive index composed of connection and integration, the accessibility and network operation efficiency of the railway network in different time periods is calculated, while the fairness of the network is analyzed by the fairness indicators constructed with the integration and location entropy from the perspective of horizontal and vertical fairness respectively. From the analysis of the efficiency and fairness of the railway passenger transport network, the study finds: (1) There is a strong regularity in regional system accessibility change; (2) The problems of efficiency and fairness are different in different time periods; (3) The improvement of efficiency will lead to the decline of horizontal fairness to a certain extent, while from the perspective of vertical fairness, the supply-demand situation has changed smoothly with time; (4) The network connection efficiency of Shanghai, Jiangsu and Zhejiang regions is higher than that of the western regions such as Anqing and Chizhou; (5) The marginalization of Nantong, Yancheng, Yangzhou, Taizhou is obvious. The study explores the application of spatial syntactic theory in regional traffic analysis, in order to provide a reference for the development of urban agglomeration transportation network.

Keywords: spatial syntax, the Yangtze River Delta, railway passenger time, efficiency and fairness

Procedia PDF Downloads 138
2713 Combined Use of Microbial Consortia for the Enhanced Degradation of Type-IIx Pyrethroids

Authors: Parminder Kaur, Chandrajit B. Majumder

Abstract:

The unrestrained usage of pesticides to meet the burgeoning demand of enhanced crop productivity has led to the serious contamination of both terrestrial and aquatic ecosystem. The remediation of mixture of pesticides is a challenging affair regarding inadvertent mixture of pesticides from agricultural lands treated with various compounds. Global concerns about the excessive use of pesticides have driven the need to develop more effective and safer alternatives for their remediation. We focused our work on the microbial degradation of a mixture of three Type II-pyrethroids, namely Cypermethrin, Cyhalothrin and Deltamethrin commonly applied for both agricultural and domestic purposes. The fungal strains (Fusarium strain 8-11P and Fusarium sp. zzz1124) had previously been isolated from agricultural soils and their ability to biotransform this amalgam was studied. In brief, the experiment was conducted in two growth systems (added carbon and carbon-free) enriched with variable concentrations of pyrethroids between 100 to 300 mgL⁻¹. Parameter optimization (pH, temperature, concentration and time) was done using a central composite design matrix of Response Surface Methodology (RSM). At concentrations below 200 mgL⁻¹, complete removal was observed; however, degradation of 95.6%/97.4 and 92.27%/95.65% (in carbon-free/added carbon) was observed for 250 and 300 mgL⁻¹ respectively. The consortium has been shown to degrade the pyrethroid mixture (300 mg L⁻¹) within 120 h. After 5 day incubation, the residual pyrethroids concentration in unsterilized soil were much lower than in sterilized soil, indicating that microbial degradation predominates in pyrethroids elimination with the half-life (t₁/₂) of 1.6 d and R² ranging from 0.992-0.999. Overall, these results showed that microbial consortia might be more efficient than single degrader strains. The findings will complement our current understanding of the bioremediation of mixture of Type II pyrethroids with microbial consortia and potentially heighten the importance for considering bioremediation as an effective alternative for the remediation of such pollutants.

Keywords: bioremediation, fungi, pyrethroids, soil

Procedia PDF Downloads 154
2712 Adsorption of Dyes and Iodine: Reaching Outstanding Kinetics with CuII-Based Metal–Organic Nanoballs

Authors: Eder Amayuelas, Begoña Bazán, M. Karmele Urtiaga, Gotzone Barandika, María I. Arriortua

Abstract:

Metal Organic Frameworks (MOFs) have attracted great interest in recent years, taking a lead role in the field of catalysis, drug delivery, sensors and absorption. In the past decade, promising results have been reported specifically in the field of adsorption, based on the topology and chemical features of this type of porous material. Thus, its application in industry and environment for the adsorption of pollutants is presented as a response to an increasingly important need. In this area, organic dyes are nowadays widely used in many industries including medicine, textile, leather, printing and plastics. The consequence of this fact is that dyes are present as emerging pollutants in soils and water where they remain for long periods of time due to their high stability, with a potential risk of toxicity in wildlife and in humans. On the other hand, the presence of iodine in soils, water and gas as a nuclear activity pollutant product or its extended use as a germicide is still a problem in many countries, which indicates the imperative need for its removal. In this context, this work presents the characterization as an adsorbent of the activated compound αMOP@Ei2-1 obtained from the already reported [Cu₂₄(m-BDC)₂₄(DMF)₂₀(H₂O)₄]•24DMF•40H₂O (MOP@Ei2-1), where m-BDC is the 1,3-benzenedicarboxylic ligand and DMF is N,N′-dimethylformamide. The structure of MOP@Ei2-1 consists of Cu24 clusters arranged in such a way that 12 paddle-wheels are connected through m-BDC ligands. The clusters exhibit an internal cavity where crystallization molecules of DMF and water are located. Adsorption of dyes and iodine as pollutant examples has been carried out, focusing attention on the kinetics of the rapid process.

Keywords: adsorption, organic dyes, iodine, metal organic frameworks

Procedia PDF Downloads 280
2711 Empirical Examination of High Performance Work System, Organizational Commitment and Organizational Citizen Behavior: A Mediation of Model of Vietnam Organizations

Authors: Giang Vu, Duong Nguyen, Yuan-Ling Chen

Abstract:

Vietnam is a fast developing country with highly economic growth, and Vietnam organizations strive to utilize high performance work system (HPWS) in reinforcing employee in-role performance. HPWS, a bundle of human resource (HR) practices, are composed of eight sets of HR practices, namely selective staffing, extensive training, internal mobility, employment security, clear job description, result-oriented appraisal, incentive reward, and participation. However, whether HPWS stimulate employee extra-role behaviors remains understudied in a booming economic context. In this study, we aim to investigate organizational citizenship behavior (OCB) in a Vietnam context and, as a central issue, disentangle how HPWS elicits in employee OCB. On the other hand, recently, a deliberation of so-called 'black-box' HPWS issue has explored the role of employee commitment, suggesting that organizational commitment is a compelling source of employee OCB. We draw upon social exchange theory to predict that when employees perceive the organizational investment, like HPWS, in heightening their abilities, knowledge, and motivation, they are more likely to pay back with commitment; consequently, they will take initiatives in OCB. Hence, we hypothesize an individual level framework, in which organizational commitment mediates the positive relationship between HPWS and OCB. We collected data on HPWS, organizational commitment, OCB, and demographic variables, all at line managers of Vietnamese firms in Hanoi and Hochiminh. We conclude with research findings, implications, and future research suggestions.

Keywords: high performance work system, organizational citizenship behavior, organizational commitment, Vietnam

Procedia PDF Downloads 313
2710 Growth Response and Nutrient Utilization of African Mud Catfish Clarias gariepinus (Burchell, 1822) Fingerlings Fed Processed Macroalgae and Macroalgae-Based Formulated Feeds

Authors: A. O Amosu, A. M Hammed, G. W. Maneveldt, D. V. Robertson-Andersson

Abstract:

In aquaculture, feed utilization is an important factor affecting growth of the target species, and thus the success of the aquaculture operation. Growth of C. gariepinus fingerlings (weight 1.60 ± 0.05 g; length 4.50 ± 0.07cm) was monitored in a closed door hatchery for a period of 21 days in an experiment consisting of 4 treatments stocked at 20 fish/10 litre tanks, fed in triplicate twice daily (08:30, 17:30) at 4% body weight with weight changes recorded every 3 days. Treatments were: 1) FeedX; 2) 35% crude protein diet + non enriched Ulva spp (11.18% crude protein) (CD + NEU); 3) 35% crude protein diet + enriched Ulva spp (11.98% crude protein)(CD +EU) and 4) control diet of 35% crude protein (CD). The production of Ulva spp. biomass was cultivated for a period of 3 months. The result shows that the fish fed macroalgal enriched diet had good growth, though no significant difference (p > 0.05) was recorded amongst the weight gain, %weight gain, specific growth rates and nitrogen metabolism of diets CD + NEU, CD + EU and CD. Significant differences (p < 0.05), were, however, found in the food conversion ratio (FCR) and gross food conversion ratio (gFCR) among the fingerlings across all the different experimental diets. The best FCRs were recorded for control diet (0.79 ± 2.39) and the Ulva enriched (1.75 ± 1.34) diets. The results suggest that the fingerlings were able to utilize Ulva supplemented with control diet better than the FeedX. We have shown that Ulva supplemented diets are good substitutes for formulated and commercial feeds, with potential to be successful fish feed in aquaculture systems.

Keywords: aquaculture, clarias gariepinus, growth, macroalgae, nutrient, ulva

Procedia PDF Downloads 705
2709 The Aesthetic and Critiques of Weimar Democracy: The Counter and Complement to Carl Schmitt’s Political Myth

Authors: Peter Jin

Abstract:

Ever since the recent resurgence of interest in political theorist Carl Schmitt’s work, much of the current analysis on Schmitt has fo-cused on evaluating Schmitt’s legacy by exposing contradictions in his rationale. Rather than condemn such contradictions, this paper instead seeks to analyze these contradictions in an effort to better understand the radical shift in Schmitt’s intellectual trajectory from an astute critic of liberal democracy to a fascist apologist towards the end of the Weimar period. An essential part of this change is his interest in what Schmitt called ‘the emergence of aesthetics.’ Schmitt diagnosed the underlying issue with the aesthetic in the political sphere to be its irrationalism, indifference, and indeci-siveness. For Schmitt, the latter two of these were especially prob-lematic for two of his key concepts: the ‘political’ and ‘the shared historical reality.’ Schmitt’s radical depiction of ‘the political’ as an existential opposition of allegiances that necessitated a state of emergency and a decisionist sovereign political struggle required an equally radical justification, or Schmitt’s call for ‘a shared his-torical reality’ not based in historical fact yet able to mobilize the masses. In this way, Schmitt clearly condemns the indifferent, indecisive aesthetic that runs against his decisionist, action-oriented political theory. Yet despite his firm stance against aestheticism, Schmitt himself used the evocative and irrational power of aesthet-icism as a tool to present his own ‘political myth’ that compelled believers to join in decisive unity against a common enemy. In short, Schmitt’s contradictions on aestheticism and his creation of a ‘political myth’ suggest that Schmitt’s underlying conflict with aestheticism was not as much of an issue of irrationality as it was a chronic preoccupation with coercing concrete action at the expense of rational deliberation.

Keywords: aesthetics of the political, Carl Schmitt, political myth, Weimar democracy

Procedia PDF Downloads 149
2708 Development and Pre-clinical Evaluation of New ⁶⁴Cu-NOTA-Folate Conjugates for PET Imaging of Folate Receptor-Positive Tumors

Authors: Norah Al Hokbany, Ibrahim Al Jammaz, Basem Al Otaibi, Yousif Al Malki, Subhani M. Okarvi

Abstract:

Objective: The folate receptor is over-expressed in a wide variety of human tumors. Conjugates of folate have been shown to be selectively taken up by tumor cells via the folate receptor. In an attempt to develop new folate radiotracers with favorable biochemical properties for detecting folate receptor-positive cancers. Methods: we synthesized ⁶⁴Cu-NOTA- and ⁶⁴Cu-NOTAM-folate conjugates using a straightforward and simple one-step reaction. Radiochemical yields were greater than 95% (decay-corrected) with a total synthesis time of less than 20 min. Results: Radiochemical purities were always greater than 98% without high-performance liquid chromatography (HPLC) purification. These synthetic approaches hold considerable promise as a rapid and simple method for ⁶⁴Cu-folate conjugate preparation with high radiochemical yield in a short synthesis time. In vitro tests on the KB cell line showed that significant amounts of the radio conjugates were associated with cell fractions. Bio-distribution studies in nude mice bearing human KB xenografts demonstrated a significant tumor uptake and favorable bio-distribution profile for ⁶⁴Cu-NOTA- and ⁶⁴Cu-NOTAM-folate conjugate. The uptake in the tumors was blocked by the excess injection of folic acid, suggesting a receptor-mediated process. Conclusion: These results demonstrate that the ⁶⁴Cu-NOTAM-folate conjugate may be useful as a molecular probe for the detection and staging of folate receptor-positive cancers, such as ovarian cancer and their metastasis, as well as monitoring tumor response to treatment.

Keywords: folate, receptor, tumor imaging, ⁶⁴Cu-NOTA-folate, PET

Procedia PDF Downloads 115
2707 Enhanced Optical Nonlinearity in Bismuth Borate Glass: Effect of Size of Nanoparticles

Authors: Shivani Singla, Om Prakash Pandey, Gopi Sharma

Abstract:

Metallic nanoparticle doped glasses has lead to rapid development in the field of optics. Large third order non-linearity, ultrafast time response, and a wide range of resonant absorption frequencies make these metallic nanoparticles more important in comparison to their bulk material. All these properties are highly dependent upon the size, shape, and surrounding environment of the nanoparticles. In a quest to find a suitable material for optical applications, several efforts have been devoted to improve the properties of such glasses in the past. In the present study, bismuth borate glass doped with different size gold nanoparticles (AuNPs) has been prepared using the conventional melt-quench technique. Synthesized glasses are characterized by X-ray diffraction (XRD) and Fourier Transformation Infrared spectroscopy (FTIR) to observe the structural modification in the glassy matrix with the variation in the size of the AuNPs. Glasses remain purely amorphous in nature even after the addition of AuNPs, whereas FTIR proposes that the main structure contains BO₃ and BO₄ units. Field emission scanning electron microscopy (FESEM) confirms the existence and variation in the size of AuNPs. Differential thermal analysis (DTA) depicts that prepared glasses are thermally stable and are highly suitable for the fabrication of optical fibers. The nonlinear optical parameters (nonlinear absorption coefficient and nonlinear refractive index) are calculated out by using the Z-scan technique with a Ti: sapphire laser at 800 nm. It has been concluded that the size of the nanoparticles highly influences the structural thermal and optical properties system.

Keywords: bismuth borate glass, different size, gold nanoparticles, nonlinearity

Procedia PDF Downloads 127
2706 Hypotensive effect of Cardiospermum halicacabum Linn. in Anesthetized Rats

Authors: Huma Shareef, Ghazala H. Rizwani, Ahsana Dar

Abstract:

In traditional medicine Cardiospermum halicacabum L. (Sapindeaceae) is used against various ailments. In current investigation searching a new remedy that will available easily, non expensive, able to lower hypertension and standardize blood pressure, made us to develop an herbal medicine. Crude ethanol extract of C. halicacabum and its various fractions ethyl acetate and butanol showed a dose-dependent hypotensive effect in anaesthetized rats. The trachea was exposed and freed from connective tissue and incubated by cannula to facilitate spontaneous respiration. The right carotid artery and left jugular vein were cannulated with polyethylene tubing PE-50 for monitoring blood pressure changes via pressure transducer (Gould P23 ID) connected to a Grass model 79D polygraph and for i.v. injection, respectively. Drugs or the plant extracts were administered at a constant volume of 0.5 ml/kg, followed by injection of 0.2 ml of saline that flushed the cannula. Systolic, diastolic and mean arterial blood pressure (MABP) was measured in mm Hg and heart rate in beats/min. Ethanol extract of C. halicacabum showed a significant activity at 50 mg/kg dose. Ethyl acetate fraction (10, 20, 30, 40, and 50 mg/kg) induced dose dependent fall in systolic and diastolic blood pressure, heart rate of rats. At 10-30 mg/kg the hypotensive effect was non significantly reduced by 10 -15%. However, the extract at 40 mg/kg induced significant hypotensive effect calculated as 30.95±3.2% MABP and this effect persists till 50 mg/kg. The higher polar fraction (butanol) of the whole plant failed to produce any significant response against MABP at all the tested doses (10-50 mg/kg). C. halicacabum lowers blood pressure, exerts a dose-dependent hypotensive effect, can be used as hypotensor.

Keywords: cardiospermum halicacabum, calcium channel blocker, hypotensive, various extracts

Procedia PDF Downloads 510
2705 Evaluating the Impact of Future Scenarios on Water Availability and Demand Based on Stakeholders Prioritized Water Management Options in the Upper Awash Basin, Ethiopia

Authors: Adey Nigatu Mersha, Ilyas Masih, Charlotte de Fraiture, Tena Alamirew

Abstract:

Conflicts over water are increasing mainly as a result of water scarcity in response to higher water demand and climatic variability. There is often not enough water to meet all demands for different uses. Thus, decisions have to be made as to how the available resources can be managed and utilized. Correspondingly water allocation goals, practically national water policy goals, need to be revised accordingly as the pressure on water increases from time to time. A case study is conducted in the Upper Awash Basin, Ethiopia, to assess and evaluate prioritized comprehensive water demand management options based on the framework of integrated water resources management in account of stakeholders’ knowledge and preferences as well as practical prominence within the Upper Awash Basin. Two categories of alternative management options based on policy analysis and stakeholders' consultation were evaluated against the business-as-usual scenario by using WEAP21 model as an analytical tool. Strong effects on future (unmet) demands are observed with major socio-economic assumptions and forthcoming water development plans. Water management within the basin will get more complex with further abstraction which may lead to an irreversible damage to the ecosystem. It is further confirmed through this particular study that efforts to maintain users’ preferences alone cannot insure economically viable and environmentally sound development and vice versa. There is always a tradeoff between these factors. Hence, all of these facets must be analyzed separately, related with each other in equal footing, and ultimately taken up in decision making in order for the whole system to function properly.

Keywords: water demand, water availability, WEAP21, scenarios

Procedia PDF Downloads 283
2704 Amino Acid Responses of Wheat Cultivars under Glasshouse Drought Accurately Predict Yield-Based Drought Tolerance in the Field

Authors: Arun K. Yadav, Adam J. Carroll, Gonzalo M. Estavillo, Greg J. Rebetzke, Barry J. Pogson

Abstract:

Water limits crop productivity, so selecting for minimal yield-gap in drier environments is critical to mitigate against climate change and land-use pressures. To date, no markers measured in glasshouses have been reported to predict field-based drought tolerance. In the field, the best measure of drought tolerance is yield-gap; but this requires multisite trials that are an order of magnitude more resource intensive and can be impacted by weather variation. We investigated the responses of relative water content (RWC), stomatal conductance (gs), chlorophyll content and metabolites in flag leaves of commercial wheat (Triticum aestivum L.) cultivars to three drought treatments in the glasshouse and field environments. We observed strong genetic associations between glasshouse-based RWC, metabolites and Yield gap-based Drought Tolerance (YDT): the ratio of yield in water-limited versus well-watered conditions across 24 field environments spanning sites and seasons. Critically, RWC response to glasshouse drought was strongly associated with both YDT (r2 = 0.85, p < 8E-6) and RWC under field drought (r2 = 0.77, p < 0.05). Multiple regression analyses revealed that 98% of genetic YDT variance was explained by drought responses of four metabolites: serine, asparagine, methionine and lysine (R2 = 0.98; p < 0.01). Fitted coefficients suggested that, for given levels of serine and asparagine, stronger methionine and lysine accumulation was associated with higher YDT. Collectively, our results demonstrate that high-throughput, targeted metabolic phenotyping of glasshouse-grown plants may be an effective tool for the selection of wheat cultivars with high YDT in the field.

Keywords: drought stress, grain yield, metabolomics, stomatal conductance, wheat

Procedia PDF Downloads 267
2703 “Referral for re-submission” – The Case of EFL Applied Linguistics Doctoral Defense Sessions

Authors: Alireza Jalilifar, Nadia Mayahi

Abstract:

An oral defense is the examination of a doctoral program in which the candidates display their academic capacity through sharing and disseminating the findings of their study and defending their position. In this challenging criticism-generating context, the examiners evaluate the PhD dissertation critically so as to confirm its scholarly merit or lack of it. To identify the examiners’ expectations of the viva, this study used a conversation analytic approach for analyzing the data. The research is inductive in that it seeks to develop theory that is grounded in the data. The data comprised transcripts of the question and answer section of two applied linguistics doctoral defense sessions from two accredited Iranian state universities in 2019, both of which are among the top Iranian universities on the list of Times Higher Education World University Rankings. In spite of the similar shortcomings and deficiencies, for instance, in terms of innovation, development, sampling, and treatment, raised by the examiners, one of these defenses passed with distinction while the other was referred for re-submission. It seems that the outcome of a viva, in an EFL context, not only depends on adherence to the rules and regulations of doctoral research but is also influenced to a certain extent by the strictness of the examiners and the candidates’ language proficiency and effective negotiation and communication skills in this confrontational communicative event. The findings of this study provide evidence for the issues determining the success or failure of PhD candidates in displaying their claims of scholarship during their defense sessions. This study has implications for both applied linguistics doctoral students and academics in EFL contexts who try to prove and authenticate the doctorateness of a dissertation.

Keywords: academic discourse, conversation analysis, doctoral defense, doctorateness, EFL

Procedia PDF Downloads 159
2702 Dynamic Analysis of Mono-Pile: Spectral Element Method

Authors: Rishab Das, Arnab Banerjee, Bappaditya Manna

Abstract:

Mono-pile foundations are often used in soft soils in order to support heavy mega-structures, whereby often these deep footings may undergo dynamic excitation due to many causes like earthquake, wind or wave loads acting on the superstructure, blasting, and unbalanced machines, etc. A comprehensive analytical study is performed to study the dynamics of the mono-pile system embedded in cohesion-less soil. The soil is considered homogeneous and visco-elastic in nature and is analytically modeled using complex springs. Considering the N number of the elements of the pile, the final global stiffness matrix is obtained by using the theories of the spectral element matrix method. Further, statically condensing the intermediate internal nodes of the global stiffness matrix results to a smaller sub matrix containing the nodes experiencing the external translation and rotation, and the stiffness and damping functions (impedance functions) of the embedded piles are determined. Proper plots showing the variation of the real and imaginary parts of these impedance functions with the dimensionless frequency parameter are obtained. The plots obtained from this study are validated by that provided by Novak,1974. Further, the dynamic analysis of the resonator impregnated pile is proposed within this study. Moreover, with the aid of Wood's 1g laboratory scaling law, a proper scaled-down resonator-pile model is 3D printed using PLA material. Dynamic analysis of the scaled model is carried out in the time domain, whereby the lateral loads are imposed on the pile head. The response obtained from the sensors through the LabView software is compared with the proposed theoretical data.

Keywords: mono-pile, visco-elastic, impedance, LabView

Procedia PDF Downloads 125
2701 The Role of Sustainable Financing Models for Smallholder Tree Growers in Ghana

Authors: Raymond Awinbilla

Abstract:

The call for tree planting has long been set in motion by the government of Ghana. The Forestry Commission encourages plantation development through numerous interventions including formulating policies and enacting legislations. However, forest policies have failed and that has generated a major concern over the vast gap between the intentions of national policies and the realities established. This study addresses three objectives;1) Assessing the farmers' response and contribution to the tree planting initiative, 2) Identifying socio-economic factors hindering the development of smallholder plantations as a livelihood strategy, and 3) Determining the level of support available for smallholder tree growers and the factors influencing it. The field work was done in 12 farming communities in Ghana. The article illuminates that farmers have responded to the call for tree planting and have planted both exotic and indigenous tree species. Farmers have converted 17.2% (369.48ha) of their total land size into plantations and have no problem with land tenure. Operations and marketing constraints include lack of funds for operations, delay in payment, low price of wood, manipulation of price by buyers, documentation by buyers, and no ready market for harvesting wood products. Environmental institutions encourage tree planting; the only exception is with the Lands Commission. Support availed to farmers includes capacity building in silvicultural practices, organisation of farmers, linkage to markets and finance. Efforts by the Government of Ghana to enhance forest resources in the country could rely on the input of local populations.

Keywords: livelihood strategy, marketing constraints, environmental institutions, silvicultural practices

Procedia PDF Downloads 63