Search results for: premature chromosome condensation procedure

Authors: B. G. Abiona, T. D. Odetayo, S. O. Adeogun, O. E. Fakoya

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This study determined the effects of workplace power on employees’ job performance in selected federal universities of agriculture in Nigeria. Two hundred and twenty-seven (227) employees were randomly drawn from the selected universities through a multistage sampling procedure. The mean age of the employees was 38 years, mostly (60.8%) male. Results indicated that the overall job performance was significantly influenced by an expert (b = 0.287, p<0.01) and legitimate power (b = -0.279, p<0.05). The findings clearly showed that supervisor has considerable professional experience to draw from in helping subordinates to do their work better because they have specialized training in their field of study, and subordinates prefer to do what the supervisor suggests because of their professional expertise, which greatly influences employees’ job performance. A policy that will ensure transparency in all administrative procedures, with a formal line of authority that will enhance the thriving of legitimate power, should be established within organisation is recommended.

Keywords: workplace power, employees, job performance, agricultural unversities

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Authors: Ryan A. Black, Stacey A. McCaffrey

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Over the past few decades, great strides have been made towards improving the science in the measurement of psychological constructs. Item Response Theory (IRT) has been the foundation upon which statistical models have been derived to increase both precision and accuracy in psychological measurement. These models are now being used widely to develop and refine tests intended to measure an individual's level of academic achievement, aptitude, and intelligence. Recently, the field of clinical psychology has adopted IRT models to measure psychopathological phenomena such as depression, anxiety, and addiction. Because advances in IRT measurement models are being made so rapidly across various fields, it has become quite challenging for psychologists and other behavioral scientists to keep abreast of the most recent developments, much less learn how to employ and decide which models are the most appropriate to use in their line of work. In the same vein, IRT measurement models vary greatly in complexity in several interrelated ways including but not limited to the number of item-specific parameters estimated in a given model, the function which links the expected response and the predictor, response option formats, as well as dimensionality. As a result, inferior methods (a.k.a. Classical Test Theory methods) continue to be employed in efforts to measure psychological constructs, despite evidence showing that IRT methods yield more precise and accurate measurement. To increase the use of IRT methods, this study endeavors to provide a comprehensive overview of binary IRT models; that is, measurement models employed on test data consisting of binary response options (e.g., correct/incorrect, true/false, agree/disagree). Specifically, this study will cover the most basic binary IRT model, known as the 1-parameter logistic (1-PL) model dating back to over 50 years ago, up until the most recent complex, 4-parameter logistic (4-PL) model. Binary IRT models will be defined mathematically and the interpretation of each parameter will be provided. Next, all four binary IRT models will be employed on two sets of data: 1. Simulated data of N=500,000 subjects who responded to four dichotomous items and 2. A pilot analysis of real-world data collected from a sample of approximately 770 subjects who responded to four self-report dichotomous items pertaining to emotional consequences to alcohol use. Real-world data were based on responses collected on items administered to subjects as part of a scale-development study (NIDA Grant No. R44 DA023322). IRT analyses conducted on both the simulated data and analyses of real-world pilot will provide a clear demonstration of how to construct, evaluate, and compare binary IRT measurement models. All analyses will be performed using the new IRT procedure in SAS 9.4. SAS code to generate simulated data and analyses will be available upon request to allow for replication of results.

Keywords: instrument development, item response theory, latent trait theory, psychometrics

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Authors: Sinead Morrison, Ann Swillen, Therese Van Amelsvoort, Samuel Chawner, Elfi Vergaelen, Michael Owen, Marianne Van Den Bree

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22q11.2 Deletion Syndrome (22q11.2DS) is caused by the deletion of approximately 60 genes on chromosome 22 and is associated with high rates of neurodevelopmental disorders such as Attention Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorders (ASD). The presentation of these disorders in 22q11.2DS is reported to be comparable to idiopathic forms and therefore presents a valuable model for understanding mechanisms of neurodevelopmental disorders. Cognitive deficits are thought to be a core feature of neurodevelopmental disorders, and possibly manifest in behavioural and emotional problems. There have been mixed findings in 22q11.2DS on whether the presence of ADHD or ASD is associated with greater cognitive deficits. Furthermore, the influence of developmental stage has never been taken into account. The aim was therefore to examine whether the presence of ADHD or ASD was associated with cognitive deficits in childhood and/or adolescence in 22q11.2DS. We conducted the largest study to date of this kind in 22q11.2DS. The same battery of tasks measuring processing speed, attention and spatial working memory were completed by 135 participants with 22q11.2DS. Wechsler IQ tests were completed, yielding Full Scale (FSIQ), Verbal (VIQ) and Performance IQ (PIQ). Age-standardised difference scores were produced for each participant. Developmental stages were defined as children (6-10 years) and adolescents (10-18 years). ADHD diagnosis was ascertained from a semi-structured interview with a parent. ASD status was ascertained from a questionnaire completed by a parent. Interaction and main effects of cognitive performance of those with or without a diagnosis of ADHD or ASD in childhood or adolescence were conducted with 2x2 ANOVA. Significant interactions were followed up with t-tests of simple effects. Adolescents with ASD displayed greater deficits in all measures (processing speed, p = 0.022; sustained attention, p = 0.016; working memory, p = 0.006) than adolescents without ASD; there was no difference between children with and without ASD. There were no significant differences on IQ measures. Both children and adolescents with ADHD displayed greater deficits on sustained attention (p = 0.002) than those without ADHD. There were no significant differences on any other measures for ADHD. Magnitude of cognitive deficit in individuals with 22q11.2DS varied by cognitive domain, developmental stage and presence of neurodevelopmental disorder. Adolescents with 22q11.2DS and ASD showed greater deficits on all measures, which suggests there may be a sensitive period in childhood to acquire these domains, or reflect increasing social and academic demands in adolescence. The finding of poorer sustained attention in children and adolescents with ADHD supports previous research and suggests a specific deficit which can be separated from processing speed and working memory. This research provides unique insights into the association of ASD and ADHD with cognitive deficits in a group at high genomic risk of neurodevelopmental disorders.

Keywords: 22q11.2 deletion syndrome, attention deficit hyperactivity disorder, autism spectrum disorder, cognitive development

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Authors: Sadia Ata, Anila Tabassum, Samina ghafoor, Ijaz ul Mohsin, Azam Muktar

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Heavy metal ions such as Pb2+, Cd2+, Zn2+, Ni2+ and Hg2+, in wastewater are considered as the serious environmental problem. Among these heavy metals, Lead or Pb (II) is the most toxic heavy metal. Exposure to lead causes damage of nervous system, mental retardation, renal kidney disease, anemia and cancer in human beings. Adsorption is the most widely used method to remove metal ions based on the physical interaction between metal ions and sorbents. With the development of nanotechnology, nano-sized materials are proved to be effective sorbents for the removal of heavy metal ions from wastewater due to their unique structural properties. The present work mainly focuses on the synthesis of NiO and ZnO nanoparticles for the removal of Lead ions, their preparation, characterization by XRD, FTIR, SEM, and TEM, adsorption characteristics and mechanism, along with adsorption isotherm model and adsorption kinetics to understand the adsorption procedure.

Keywords: heavy metal, adsorption isotherms, nanoparticles, wastewater

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Authors: Sharmeelee Subramaniam, Muhd Harris Ramli, Fauziah Ahmad

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The application of vacuum pressure to accelerate ground consolidation has been growing significantly in recent years. This ground improvement technique has its advantages, especially in areas where suitable fill is scarce, as it minimizes the surcharge fill height required for the preloading. A study was carried out to examine the response of soft subsoil subjected to vacuum consolidation in combination with embankment loading, surcharge preloading and PVD with two-way drainage. This paper shall describe a procedure to determine the optimum surcharge height and penetration depth of prefabricated vertical drains (PVD) where vacuum consolidation is combined with the use of PVD in soft clay deposits with two-way drainage.

Keywords: prefabricated vertical drain, soft soil, surcharge preload, vacuum consolidation

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Authors: Alhusein Almahjoub, Dongyu Qiu

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This paper deals with the random access procedure in next-generation networks and presents the solution to reduce total service time (TST) which is one of the most important performance metrics in current and future internet of things (IoT) based networks. The proposed solution focuses on the calculation of optimal transmission probability which maximizes the success probability and reduces TST. It uses the information of several idle preambles in every time slot, and based on it, it estimates the number of backlogged IoT devices using Naïve Bayes estimation which is a type of supervised learning in the machine learning domain. The estimation of backlogged devices is necessary since optimal transmission probability depends on it and the eNodeB does not have information about it. The simulations are carried out in MATLAB which verify that the proposed solution gives excellent performance.

Keywords: random access, LTE/LTE-A, 5G, machine learning, Naïve Bayes estimation

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Authors: Azadeh Askarinejad, Parmida Hayati, Parham Hayati, Reza Parchami

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Curing is a very important factor in the ultimate strength and durability of roller compacted concrete pavements (RCCP). Curing involves keeping the concrete is saturated or close to saturation point. Since maintaining concrete moisture has a significant impact on its mechanical properties, permeability and durability, curing is important. The most common procedure for curing of roller compacted concrete is using a white pigmented curing compound. This method is effective, economical and fast. In the present study, different curing compounds were applied on concrete specimens and the results of their effects on the mechanical properties were compared with each other and usual methods of curing in order to select appropriate materials and methods of curing for RCCP construction.

Keywords: curing compounds, roller compacted concrete pavements, mechanical properties, durability

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Authors: Domingo Planes Meseguer, Raffaele Danilo Esposito, Maria Del Pilar Dorado Rodriguez

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Monthly quality control checks for a Radiation Therapy Linac may be performed is a simple and efficient way once they have been standardized and protocolized. On the other hand this checks, in spite of being imperatives, require a not negligible execution times in terms of machine time and operators time. Besides it must be taken into account the amount of disposable material which may be needed together with the use of commercial software for their performing. With the aim of optimizing and standardizing mechanical-geometric checks and multi leaves collimator checks, we decided to implement a protocol which makes use of the Electronic Portal Imaging Device (EPID) available on our Linacs. The user is step by step guided by the software during the whole procedure. Acquired images are automatically analyzed by our programs all of them written using only free software.

Keywords: quality control checks, linac, radiation oncology, medical physics, free software

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Authors: Seyed Abolhassan Naeini, Maedeh Akhavan Tavakkoli

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Evaluating the shear wave velocity (V_s) and primary wave velocity (Vₚ) is necessary to identify the ground type of the site. Identifying the soil type based on different codes can affect the dynamic analysis of geotechnical properties. This study aims to separate the underground layers at the project site based on the shear wave and primary wave velocity (Sₚ) in different depths and determine dynamic elastic modulus based on the shear wave velocity. Bandar Anzali is located in a tectonically very active area. Several active faults surround the study site. In this case, a field investigation of downhole testing is conducted as a geophysics method to identify the ground type.

Keywords: downhole, geophysics, shear wave velocity, case-study

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Authors: Baeza S. Roberto

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The knitted fabric suffers a deformation in its dimensions due to stretching and tension factors, transverse and longitudinal respectively, during the process in rectilinear knitting machines so it performs a dry relaxation shrinkage procedure and thermal action of prefixed to obtain stable conditions in the knitting. This paper presents a dry relaxation shrinkage prediction of Bordeaux fiber using a feed forward neural network and linear regression models. Six operational alternatives of shrinkage were predicted. A comparison of the results was performed finding neural network models with higher levels of explanation of the variability and prediction. The presence of different reposes are included. The models were obtained through a neural toolbox of Matlab and Minitab software with real data in a knitting company of Southern Guanajuato. The results allow predicting dry relaxation shrinkage of each alternative operation.

Keywords: neural network, dry relaxation, knitting, linear regression

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Authors: Chen Li-Ching

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The multinomial logistic regression model is used popularly for inferring the relationship of risk factors and disease with multiple categories. This study based on the discrepancy between the nonparametric maximum likelihood estimator and semiparametric maximum likelihood estimator of the cumulative distribution function to propose a Kolmogorov-Smirnov type test statistic to assess adequacy of the multinomial logistic regression model for case-control data. A bootstrap procedure is presented to calculate the critical value of the proposed test statistic. Empirical type I error rates and powers of the test are performed by simulation studies. Some examples will be illustrated the implementation of the test.

Keywords: case-control studies, goodness-of-fit test, Kolmogorov-Smirnov test, multinomial logistic regression

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Authors: Y. Muto, S. Araki, H. Yamamoto

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The separation of oxygen is one key technology to improve the efficiency and to reduce the cost for the processed of the partial oxidation of the methane and the condensation of the carbon dioxide. Particularly, carbon dioxide at high concentration would be obtained by the combustion using pure oxygen separated from air. However, the oxygen separation process occupied the large part of energy consumption. Therefore, it is considered that the membrane technologies enable to separation at lower cost and lower energy consumption than conventional methods. In this study, it is examined that the separation of oxygen using membranes of mixed conductors. Oxygen permeation through the membrane is occurred by the following three processes. At first, the oxygen molecules dissociate into oxygen ion at feed side of the membrane, subsequently, oxygen ions diffuse in the membrane. Finally, oxygen ions recombine to form the oxygen molecule. Therefore, it is expected that the membrane of thickness and material, or catalysts of the dissociation and recombination affect the membrane performance. However, there is little article about catalysts for the dissociation and recombination. We confirmed the performance of La0.6Sr0.4Co1.0O3-δ (LSC) based catalyst which was commonly used as the dissociation and recombination. It is known that the adsorbed amount of oxygen increase with the increase of doped Fe content in B site of LSC. We prepared the catalysts of La0.1Sr0.9Co0.9Fe0.1O3-δ(C9F1), La0.1Sr0.9Co0.5Fe0.5O3-δ(C5F5) and La0.1Sr0.9Co0.3Fe0.7O3-δ(C7F3). Also, we used Pr2NiO4 type mixed conductor as a membrane material. (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ(PLNCG) shows the high oxygen permeability and the stability against carbon dioxide. Oxygen permeation experiments were carried out using a homemade apparatus at 850 -975 °C. The membrane was sealed with Pyrex glass at both end of the outside dense alumina tubes. To measure the oxygen permeation rate, air was fed to the film side at 50 ml min-1, helium as the sweep gas and reference gas was fed at 20 ml min-1. The flow rates of the sweep gas and the gas permeated through the membrane were measured using flow meter and the gas concentrations were determined using a gas chromatograph. Then, the permeance of the oxygen was determined using the flow rate and the concentration of the gas on the permeate side of the membrane. The increase of oxygen permeation was observed with increasing temperature. It is considered that this is due to the catalytic activities are increased with increasing temperature. Another reason is the increase of oxygen diffusivity in the bulk of membrane. The oxygen permeation rate is improved by using catalyst of LSC or LSCF. The oxygen permeation rate of membrane with LSCF showed higher than that of membrane with LSC. Furthermore, in LSCF catalysts, oxygen permeation rate increased with the increase of the doped amount of Fe. It is considered that this is caused by the increased of adsorbed amount of oxygen.

Keywords: membrane separation, oxygen permeation, K2NiF4-type structure, mixed conductor

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Authors: K. Boualem, T. Yahiaoui, A. Azzi

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Numerical investigations are performed to analyze the flow behavior over NACA0015 and to evaluate the efficiency of synthetic jet as active control device. The second objective of this work is to investigate the influence of momentum coefficient of synthetic jet on the flow behaviour. The unsteady Reynolds-averaged Navier-Stokes equations of the turbulent flow are solved using, k-ω SST provided by ANSYS CFX-CFD code. The model presented in this paper is a comprehensive representation of the information found in the literature. Comparison of obtained numerical flow parameters with the experimental ones shows that the adopted computational procedure reflects nearly the real flow nature. Also, numerical results state that use of synthetic jets devices has positive effects on the flow separation, and thus, aerodynamic performance improvement of NACA0015 airfoil. It can also be observed that the use of synthetic jet increases the lift coefficient about 13.3% and reduces the drag coefficient about 52.7%.

Keywords: active control, synthetic jet, NACA airfoil, CFD

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Authors: Sujeet Kumar Singh, Shiv Prasad Yadav

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This paper develops an approach for solving intuitionistic fuzzy linear fractional programming (IFLFP) problem where the cost of the objective function, the resources, and the technological coefficients are triangular intuitionistic fuzzy numbers. Here, the IFLFP problem is transformed into an equivalent crisp multi-objective linear fractional programming (MOLFP) problem. By using fuzzy mathematical programming approach the transformed MOLFP problem is reduced into a single objective linear programming (LP) problem. The proposed procedure is illustrated through a numerical example.

Keywords: triangular intuitionistic fuzzy number, linear programming problem, multi objective linear programming problem, fuzzy mathematical programming, membership function

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Authors: Nikhat Nawaz, S. Srinivasulu, P. Kesava Rao

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Feature extraction plays an important role in many remote sensing applications. Automatic extraction of water bodies is of great significance in many remote sensing applications like change detection, image retrieval etc. This paper presents a procedure for automatic extraction of water information from remote sensing images. The algorithm uses the relative location of R-colour component of the chromaticity diagram. This method is then integrated with the effectiveness of the spatial scale transformation of whole method. The whole method is based on water index fitted from spectral library. Experimental results demonstrate the improved accuracy and effectiveness of the integrated method for automatic extraction of water bodies.

Keywords: feature extraction, remote sensing, image retrieval, chromaticity, water index, spectral library, integrated method

Procedia PDF Downloads 372

Authors: Zhihui Liu, Dongmei Hao, Qian Qiu, Yang An, Lin Yang, Song Zhang, Yimin Yang, Xuwen Li, Dingchang Zheng

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Premature birth, defined as birth before 37 completed weeks of gestation is a leading cause of neonatal morbidity and mortality and has long-term adverse consequences for health. It has recently been reported that the worldwide preterm birth rate is around 10%. The existing measurement techniques for diagnosing preterm delivery include tocodynamometer, ultrasound and fetal fibronectin. However, they are subjective, or suffer from high measurement variability and inaccurate diagnosis and prediction of preterm labor. Electrohysterography (EHG) method based on recording of uterine electrical activity by electrodes attached to maternal abdomen, is a promising method to assess uterine activity and diagnose preterm labor. The purpose of this study is to analyze the difference of EHG signal features between term labor and preterm labor. Free access database was used with 300 signals acquired in two groups of pregnant women who delivered at term (262 cases) and preterm (38 cases). Among them, EHG signals from 38 term labor and 38 preterm labor were preprocessed with band-pass Butterworth filters of 0.08–4Hz. Then, EHG signal features were extracted, which comprised classical time domain description including root mean square and zero-crossing number, spectral parameters including peak frequency, mean frequency and median frequency, wavelet packet coefficients, autoregression (AR) model coefficients, and nonlinear measures including maximal Lyapunov exponent, sample entropy and correlation dimension. Their statistical significance for recognition of two groups of recordings was provided. The results showed that mean frequency of preterm labor was significantly smaller than term labor (p < 0.05). 5 coefficients of AR model showed significant difference between term labor and preterm labor. The maximal Lyapunov exponent of early preterm (time of recording < the 26th week of gestation) was significantly smaller than early term. The sample entropy of late preterm (time of recording > the 26th week of gestation) was significantly smaller than late term. There was no significant difference for other features between the term labor and preterm labor groups. Any future work regarding classification should therefore focus on using multiple techniques, with the mean frequency, AR coefficients, maximal Lyapunov exponent and the sample entropy being among the prime candidates. Even if these methods are not yet useful for clinical practice, they do bring the most promising indicators for the preterm labor.

Keywords: electrohysterogram, feature, preterm labor, term labor

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Authors: Zahra Majd, Mohsen Kalantar

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Power management and voltage regulation is one of the most important issues in microgrid (MG) control and scheduling. This paper proposes a multiobjective scheduling formulation that consists of active power costs, voltage fluctuations summation, and technical constraints of MG. Furthermore, load flow and reserve constraints are considered to achieve proper voltage regulation. A modified Jacobian matrix is presented for calculating voltage variations and Mont Carlo simulation is used for generating and reducing scenarios. To convert the problem to a mixed integer linear program, a linearization procedure for nonlinear equations is presented. The proposed model is applied to a typical low-voltage MG and two different cases are investigated. The results show the effectiveness of the proposed model.

Keywords: microgrid, energy management system, voltage fluctuations, modified Jacobian matrix

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Authors: Siva Prasad Peddi

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Silver nanoparticles were successfully synthesized from silver nitrate through a rapid green synthesis method using Eclipta prostrata leaf extract as a reducing cum stabilizing agent. The experimental procedure was readily conducted at room temperature and pressure, and could be easily scaled up. The silver nanoparticles thus obtained were characterized using UV-Visible Spectroscopy (UV-VIS) which yielded an absorption peak at 416 nm. The biomolecules responsible for capping of the bio-reduced silver nanoparticles synthesized using plant extract were successfully identified through FTIR analysis. It was evinced through Scanning Electron Microscope (SEM), and X-ray diffraction (XRD) analysis that the silver nanoparticles were crystalline in nature and spherical in shape. The average size of the particles obtained using Scherrer’s formula was 27.4 nm. The adopted technique for silver nanoparticle synthesis is suitable for large-scale production.

Keywords: silver nanoparticles, green synthesis, characterization, Eclipta prostrata

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Authors: Alinka Molnár-Tóth, Tímea Tánczos, Regina Barna, Katalin Jakab, Péter Klivényi

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Supported by neuroscientific findings, the so-called Hub-and-Spoke model of the human semantic system is based on two subcomponents of semantic cognition, namely the semantic control process and semantic representation. Our semantic knowledge is multimodal in nature, as the knowledge system stored in relation to a conception is extensive and broad, while different aspects of the conception may be relevant depending on the purpose. The motivation of our research is to develop a new diagnostic measurement procedure based on the preservation of semantic representation, which is appropriate to the specificities of the Hungarian language and which can be used to compare the non-verbal semantic knowledge of healthy and aphasic persons. The development of the test will broaden the Hungarian clinical diagnostic toolkit, which will allow for more specific therapy planning. The sample of healthy persons (n=480) was determined by the last census data for the representativeness of the sample. Based on the concept of the Pyramids and Palm Tree Test, and according to the characteristics of the Hungarian language, we have elaborated a test based on different types of semantic information, in which the subjects are presented with three pictures: they have to choose the one that best fits the target word above from the two lower options, based on the semantic relation defined. We have measured 5 types of semantic knowledge representations: associative relations, taxonomy, motional representations, concrete as well as abstract verbs. As the first step in our data analysis, we examined the normal distribution of our results, and since it was not normally distributed (p < 0.05), we used nonparametric statistics further into the analysis. Using descriptive statistics, we could determine the frequency of the correct and incorrect responses, and with this knowledge, we could later adjust and remove the items of questionable reliability. The reliability was tested using Cronbach’s α, and it can be safely said that all the results were in an acceptable range of reliability (α = 0.6-0.8). We then tested for the potential gender differences using the Mann Whitney-U test, however, we found no difference between the two (p < 0.05). Likewise, we didn’t see that the age had any effect on the results using one-way ANOVA (p < 0.05), however, the level of education did influence the results (p > 0.05). The relationships between the subtests were observed by the nonparametric Spearman’s rho correlation matrix, showing statistically significant correlation between the subtests (p > 0.05), signifying a linear relationship between the measured semantic functions. A margin of error of 5% was used in all cases. The research will contribute to the expansion of the clinical diagnostic toolkit and will be relevant for the individualised therapeutic design of treatment procedures. The use of a non-verbal test procedure will allow an early assessment of the most severe language conditions, which is a priority in the differential diagnosis. The measurement of reaction time is expected to advance prodrome research, as the tests can be easily conducted in the subclinical phase.

Keywords: communication disorders, diagnostic toolkit, neurorehabilitation, semantic knowlegde

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Authors: Mahdi Fakoor, Seyed Mohammad Navid Ghoreishi

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Initiation and propagation of cracks may cause catastrophic failures in rotating disks, and hence determination of fracture parameter in rotating disks under the different working condition is very important issue. In this paper, a comprehensive study of stress intensity factors in rotating disks containing 3D semi-elliptical cracks under the different working condition is investigated. In this regard, after verification of modeling and analytical procedure, the effects of mechanical properties, rotational velocity, and orientation of cracks on Stress Intensity Factors (SIF) in rotating disks under centrifugal loading are investigated. Also, the effects of using composite patch in reduction of SIF in rotating disks are studied. By that way, the effects of patching design variables like mechanical properties, thickness, and ply angle are investigated individually.

Keywords: stress intensity factor, semi-elliptical crack, rotating disk, finite element analysis (FEA)

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Authors: Spyridon Nikolaidis

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A modeling approach for CMOS gates is presented based on the use of the equivalent inverter. A new model for the inverter has been developed using a simplified transistor current model which incorporates the nanoscale effects for the planar technology. Parametric expressions for the output voltage are provided as well as the values of the output and supply current to be compatible with the CCS technology. The model is parametric according the input signal slew, output load, transistor widths, supply voltage, temperature and process. The transistor widths of the equivalent inverter are determined by HSPICE simulations and parametric expressions are developed for that using a fitting procedure. Results for the NAND gate shows that the proposed approach offers sufficient accuracy with an average error in propagation delay about 5%.

Keywords: CMOS gate modeling, inverter modeling, transistor current mode, timing model

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Authors: João Pereira Dos Santos

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The uneven spatial distribution of start-ups and their respective survival may reflect comparative advantages resulting from the local institutional background. For the first time, we explore this idea using Data Envelopment Analysis (DEA) to assess relative efficiency of Portuguese municipalities in this specific context. We depart from the related literature where expenditure is perceived as a desirable input by choosing a measure of fiscal responsibility and infrastructural variables in the first stage. Comparing results for 2006 and 2010, we find that mean performance decreased substantially with 1) the effects of the Global Financial Crisis; 2) as municipal population increases and 3) as financial independence decreases. A second stage is then computed employing a double-bootstrap procedure to evaluate how the regional context outside the control of local authorities (e.g. demographic characteristics and political preferences) impacts on efficiency.

Keywords: entrepreneurship, political economy, public finance, accountability, crisis, efficiency, Portuguese municipalities

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Authors: Abdulrahman Abdulrahman, Abir Abdulrahman

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The stability of slopes of earthen embankments is usually examined by Swedish slip circle method or the slices method. The factor of safety against sliding using Fellenius procedure depends upon the angle formed by the arc of sliding at the center ψ and the radius of the slip circle r. The values of both mentioned parameters ψ and r aren't precisely predicted because they are measured from the drawing. In this paper, analytical formulae were derived for finding the exact values of both ψ and r. Also this paper presents the different conditions of intersections the slip circle with the body of an earthen dam and the coordinate of intersection points. Numerical examples are chosen for demonstration the proposed solution

Keywords: earthen dams stability, , earthen embankments stability, , Fellenius method, hydraulic structures, , side slopes stability, , slices method, Swedish slip circle

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Authors: Xi Yang, Bulent Chavdar, Alan Vonseggern, Taylan Altan

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Fracture in hot precision forging of engine valves was investigated in this paper. The entire valve forging procedure was described and the possible cause of the fracture was proposed. Finite Element simulation was conducted for the forging process, with commercial Finite Element code DEFORMTM. The effects of material properties, the effect of strain rate and temperature were considered in the FE simulation. Two fracture criteria were discussed and compared, based on the accuracy and reliability of the FE simulation results. The selected criterion predicted the fracture location and shows the trend of damage increasing with good accuracy, which matches the experimental observation. Additional modification of the punch shapes was proposed to further reduce the tendency of fracture in forging. Finite Element comparison shows a great potential of such application in the mass production.

Keywords: hotforging, engine valve, fracture, tooling

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Authors: Haiu-Lan Chin, Yu-Fen Hsiao, Hua-Ying Chuang, Wei Lee

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An adult with intellectual disability generally has insufficient physical activity which is an important factor leading to premature weakness. Studies in recent years on frailty syndrome have accumulated substantial data about indicators of human aging, including unintentional weight loss, self-reported exhaustion, weakness, slow walking speed, and low physical activity. Of these indicators, hand-grip strength can be seen as a predictor of mortality, disability, complications, and increased length of hospital stay. Hand-grip strength in fact provides a comprehensive overview of one’s vitality. The research is about the investigation on hand-grip strength of adults with intellectual disabilities in facilities, institutions and workshops. The participants are 197 male adults (M=39.09±12.85 years old), and 114 female ones (M=35.80±8.2 years old) so far. The aim of the study is to figure out the performance of their hand-grip strength, and initiate the setting of training on hand-grip strength in their daily life which will decrease the weakening on their physical condition. Test items include weight, bone density, basal metabolic rate (BMR), static body balance except hand-grip strength. Hand-grip strength was measured by a hand dynamometer and classified as normal group ( ≧ 30 kg for male and ≧ 20 kg for female) and weak group ( < 30 kg for male, < 20 kg for female)The analysis includes descriptive statistics, and the indicators of grip strength fo the adults with intellectual disability. Though the research is still ongoing and the participants are increasing, the data indicates: (1) The correlation between hand-grip strength and degree of the intellectual disability (p ≦. 001), basal metabolic rate (p ≦ .001), and static body balance (p ≦ .01) as well. Nevertheless, there is no significant correlation between grip strength and basal metabolic rate which had been having significant correlation with hand-grip strength. (2) The difference between male and female subjects in hand-grip strength is significant, the hand-grip strength of male subjects (25.70±12.81 Kg) is much higher than female ones (16.30±8.89 Kg). Compared to the female counterparts, male participants indicate greater individual differences. And the proportion of weakness between male and female subjects is also different. (3) The regression indicates the main factors related to grip strength performance include degree of the intellectual disability, height, static body balance, training and weight sequentially. (4) There is significant difference on both hand-grip and static body balance between participants in facilities and workshops. The study supports the truth about the sex and gender differences in health. Nevertheless, the average hand-grip strength of left hand is higher than right hand in both male and female subjects. Moreover, 71.3% of male subjects and 64.2% of female subjects have better performance in their left hand-grip which is distinctive features especially in low degree of the intellectual disability.

Keywords: adult with intellectual disability, frailty syndrome, grip strength, physical condition

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Authors: Chrislaura Carmo, Luca Deiana, Mafalda Laranjo, Abilio Sobral, Armando Cordova

Abstract:

Photodynamic therapy (PDT) is currently used for the treatment of malignancies and premalignant tumors. It is based on the capture of a photosensitizing molecule (PS) which, when excited by light at a certain wavelength, reacts with oxygen and generates oxidizing species (radicals, singlet oxygen, triplet species) in target tissues, leading to cell death. BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indaceno) derivatives are emerging as important candidates for photosensitizer in photodynamic therapy of cancer cells due to their high triplet quantum yield. Today these dyes are relevant molecules in photovoltaic materials and fluorescent sensors. In this study, it will be demonstrated the possibility that BODIPY can be covalently linked to thioglycolic acid through the click reaction. Thiol−ene click chemistry has become a powerful synthesis method in materials science and surface modification. The design of biobased allyl-terminated precursors with high renewable carbon content for the construction of the thiol-ene polymer networks is essential for sustainable development and green chemistry. The work aims to synthesize the BODIPY (10-(4-(allyloxy) phenyl)-2,8-diethyl-5,5-difluoro-1,3,7,9-tetramethyl-5H-dipyrrolo[1,2-c:2',1'-f] [1,3,2] diazaborinin-4-ium-5-uide) and to click reaction with Thioglycolic acid. BODIPY was synthesized by the condensation reaction between aldehyde and pyrrole in dichloromethane, followed by in situ complexation with BF3·OEt2 in the presence of the base. Then it was functionalized with allyl bromide to achieve the double bond and thus be able to carry out the click reaction. The thiol−ene click was performed using DMPA (2,2-Dimethoxy-2-phenylacetophenone) as a photo-initiator in the presence of UV light (320–500 nm) in DMF at room temperature for 24 hours. Compounds were characterized by standard analytical techniques, including UV-Vis Spectroscopy, 1H, 13C, 19F NMR and mass spectroscopy. The results of this study will be important to link BODIPY to polymers through the thiol group offering a diversity of applications and functionalization. This new molecule can be tested as third-generation photosensitizers, in which the dye is targeted by antibodies or nanocarriers by cells, mainly in cancer cells, PDT and Photodynamic Antimicrobial Chemotherapy (PACT). According to our studies, it was possible to visualize a click reaction between allyl BODIPY and thioglycolic acid. Our team will also test the reaction with other thiol groups for comparison. Further, we will do the click reaction of BODIPY with a natural polymer linked with a thiol group. The results of the above compounds will be tested in PDT assays on various lung cancer cell lines.

Keywords: bodipy, click reaction, thioglycolic acid, allyl, thiol-ene click

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Authors: C. Cafaro, P. Ceci, L. De Giorgi

Abstract:

The aim of this paper is to give an assessment of environmental effects of IPPC permit conditions of installations that are in the specific territory with a high concentration of industrial activities. The IPPC permit is the permit that each operator should hold to operate the installation as stated by the directive 2010/75/UE on industrial emissions (integrated pollution prevention and control), known as IED (Industrial Emissions Directive). The IPPC permit includes all the measures necessary to achieve a high level of protection of the environment as a whole, also defining the monitoring requirements as measurement methodology, frequency, and evaluation procedure. The emissions monitoring of a specific plant may also give indications of the contribution of these emissions on the air quality of a definite area. So, it is clear that the IPPC permits are important tools both to improve the environmental framework and to achieve the air quality standards, assisting in assessing the possible industrial sources contributions to air pollution.

Keywords: IPPC, IED, emissions, permits, air quality, large combustion plants

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Authors: T. Arkle, D. Pournaras, S. Lam, B. Kumar

Abstract:

Introduction: Fundoplication is widely recognised as the best surgical option for gastro-oesophageal reflux disease (GORD) in the general population. However, there is controversy surrounding the use of conventional fundoplication in obese patients. Whilst the intra-operative failure of fundoplication, including wrap disruption, is reportedly higher in obese individuals, the more significant issue surrounds symptom recurrence post-surgery. Could a bariatric procedure be considered in obese patients for weight management, to treat the GORD, and to also reduce the risk of recurrence? Roux-en-Y gastric bypass, a widely performed bariatric procedure, has been shown to be highly successful both in controlling GORD symptoms and in weight management in obese patients. Furthermore, NICE has published clear guidelines on eligibility for bariatric surgery, with the main criteria being type 3 obesity or type 2 obesity with the presence of significant co-morbidities that would improve with weight loss. This study aims to identify the proportion of patients who undergo conventional fundoplication for GORD and/or hiatus hernia, which would have been eligible for bariatric surgery referral according to NICE guidelines. Methods: All patients who underwent fundoplication procedures for GORD and/or hiatus hernia repair at a single NHS foundation trust over a 10-year period will be identified using the Trust’s health records database. Pre-operative patient records will be used to find BMI and the presence of significant co-morbidities at the time of consideration for surgery. This information will be compared to NICE guidelines to determine potential eligibility for the bariatric surgical referral at the time of initial surgical intervention. Results: A total of 321 patients underwent fundoplication procedures between January 2011 and December 2020; 133 (41.4%) had available data for BMI or to allow BMI to be estimated. Of those 133, 40 patients (30%) had a BMI greater than 30kg/m², and 7 (5.3%) had BMI >35kg/m². One patient (0.75%) had a BMI >40 and would therefore be automatically eligible according to NICE guidelines. 4 further patients had significant co-morbidities, such as hypertension and osteoarthritis, which likely be improved by weight management surgery and therefore also indicated eligibility for referral. Overall, 3.75% (5/133) of patients undergoing conventional fundoplication procedures would have been eligible for bariatric surgical referral, these patients were all female, and the average age was 60.4 years. Conclusions: Based on this Trust’s experience, around 4% of obese patients undergoing fundoplication would have been eligible for bariatric surgical intervention. Based on current evidence, in class 2/3 obese patients, there is likely to have been a notable proportion with recurrent disease, potentially requiring further intervention. These patient’s may have benefitted more through undergoing bariatric surgery, for example a Roux-en-Y gastric bypass, addressing both their obesity and GORD. Use of patient written notes to obtain BMI data for the 188 patients with missing BMI data and further analysis to determine outcomes following fundoplication in all patients, assessing for incidence of recurrent disease, will be undertaken to strengthen conclusions.

Keywords: bariatric surgery, GORD, Nissen fundoplication, nice guidelines

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Authors: K. Brince Paul, Nagendra Pratap Singh, Shiv Govind Singh, Siva Rama Krishna Vanjari

Abstract:

In this paper, we report optimized procedure for synthesizing highly oriented, horizontally aligned, Zinc oxide (ZnO) nanowires targeted towards developing highly sensitive piezoelectric transduction elements. The synthesis was carried out using Electrospinning technique, a facile, robust, low cost technique for producing nanowires. The as-synthesized ZnO nanowires were characterized by X-ray powder diffraction (XRD), Field Emission scanning electron microscopy (FESEM) and Energy-dispersive X-ray spectroscopy (EDX).The Piezoelectric behavior of these nanowires was characterized using Peizoelectric Force microscopy (PFM). A very high d33 coefficient of 23.1 pm/V obtained through the PFM measurements is an indicative of its potential application towards developing miniaturized piezoelectric transduction elements for nanoscale devices.

Keywords: electrospinning, piezoelectric, technique, zinc oxide

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Authors: Bahaa Fawwaz‬‏

Abstract:

The study was conducted on a papyrus housed at the Museum of Islamic Art in Cairo, Egypt. This papyrus was inscribed with black ink. Twelve fungal species were isolated and identified. Five types of fungi were ultimately identified to complete the study. The isolated fungi were then incubated for three months after the aging procedure. This study investigates the in-vitro growth inhibition of Aspergillus niger, Aspergillus flavus, Penicillium chrysogenum, Trichoderma longibrachiatum Rifai, and Paecilomyces variotii on papyrus. The hyphal growth was observed using the environmental scanning electron microscope (ESEM). Natural oils, such as lavender oil, lemongrass oil, and rosemary oil, were used. The impact of these natural oils on the newly aged papyrus was assessed using scanning electron microscopy and color analysis to identify the most effective oils for inhibiting fungus growth.

Keywords: conservation, papyrus, fungi, growth, environmental, essential oils

Procedia PDF Downloads 38