Search results for: 3D shape acquisition

Authors: Isaac Laryea

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Underwater remote-operated vehicles (ROVs) are highly useful in aquatic research and underwater operations. Unfortunately, unsteady and unpredictable conditions underwater make it difficult for underwater vehicles to maintain a steady attitude during motion. Existing underwater vehicles make use of multiple thrusters positioned at specific positions on their frame to maintain a certain pose. This study proposes an alternate way of maintaining a steady attitude during horizontal motion at low speeds by making use of a thrust vector-controlled propulsion system. The study began by carrying out some preliminary calculations to get an idea of a suitable shape and form factor. Flow simulations were carried out to ensure that enough thrust could be generated to move the system. Using the Lagrangian approach, a mathematical system was developed for the ROV, and this model was used to design a control system. A PID controller was selected for the control system. However, after tuning, it was realized that a PD controller satisfied the design specifications. The designed control system produced an overshoot of 6.72%, with a settling time of 0.192s. To achieve the effect of thrust vectoring, an inverse kinematics synthesis was carried out to determine what angle the actuators need to move to. After building the system, intermittent angular displacements of 10°, 15°, and 20° were given during bench testing, and the response of the control system as well as the servo motor angle was plotted. The final design was able to move in water but was not able to handle large angular displacements as a result of the small angle approximation used in the mathematical model.

Keywords: PID control, thrust vectoring, parallel manipulators, ROV, underwater, attitude control

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Authors: Mohamed Alsafy, Samir El-Gendy, Ashraf Karkoura, Doha Shokry

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The purpose of the current study was to investigate the development of the chicken ovary. One hundred fertilized egg of Alexandria breed of chicken used. The whole embryo has undergone the light microscopic examination at HH20 (E.3), HH21 (E.3.5), HH23 (E.4), HH29 (E.6) and HH34 (E.8). The ovary has undergone the light microscopic examination at HH38 (E.12) and HH42 (E.16), SEM at HH26 (E.5), HH29 (E.6), HH36 (E.10), HH38 (E.12), HH39 (E.13) and HH42 (E.16), TEM at HH38 (E.12) and HH42 (E.16). The genital ridge appeared by a thickening of the coelomic epithelium medioventral surface of the developing mesonephroi at HH20 (E.3). The boundaries of the undifferentiating gonads defined clearly separated from the mesonephroi. The undifferentiated gonads bulged as a distinct organ in the coelomic cavity at HH23 (E.4). At the initial stages of the gonadogenesis, the germinal epithelium was stratified squamous epithelium. The PGCs appeared at the genital ridge at HH21 (E.3.5). The PGCs observed at the dorsal mesentery with few microvilli and showed positive PAS reaction due to the glycogen content in their cytoplasm. The left-right gonadal asymmetry firstly detected by the number of PGCs migrating toward the left gonadal ridge more than the right at HH20 (E.3) and the macroscopic examination of gonadal asymmetry began at HH34 (E.8). The left ovary appeared a smooth rod-shape, its stroma showed lipid droplets, and its parenchyma showed an extensive arrangement of interstitial cords at HH42 (E.16).

Keywords: ovary, Alexandria chicken, light microscopy, SEM, TEM

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Authors: Moncayo Donoso Miguelangel, Guevara Morales Johana, Kalenia Flores Kalenia, Barrera Avellaneda Luis Alejandro, Garzon Alvarado Diego Alexander

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In mammals, long bones are formed by ossification of a cartilage mold during early embryonic development, forming structures called secondary ossification centers (SOCs), a primary ossification center (POC) and growth plates. This last structure is responsible for long bone growth. During the femur growth, the morphology of the growth plate and the SOCs may vary during different developmental stages. So far there are no detailed morphological studies of the development process from embryonic to adult stages. In this work, we carried out a morphological characterization of femur development from embryonic period to adulthood in mice. 15, 17 and 19 days old embryos and 1, 7, 14, 35, 46 and 52 days old mice were used. Samples were analyzed by a computational approach, using 3D images obtained by micro-CT imaging. Results obtained in this study showed that femur, its growth plates and SOCs undergo morphological changes during different stages of development, including changes in shape, position and thickness. These variations may be related with a response to mechanical loads imposed for muscle development surrounding the femur and a high activity during early stages necessary to support the high growth rates during first weeks and years of development. This study is important to improve our knowledge about the ossification patterns on every stage of bone development and characterize the morphological changes of important structures in bone growth like SOCs and growth plates.

Keywords: development, femur, growth plate, mice

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Authors: V.Barbakadze, L.Gogilashvili, L.Amiranashvili, M.Merlani, K.Mulkijanyan

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The high-molecular fractions from the several species of two genera (Symphytum and Anchusa) of Boraginaceae family Symphytum asperum, S. caucasicum, S. officinale, and Anchusa italica were isolated. According to IR, 13C and 1H NMR, 2D heteronuclear 1H/13C HSQC spectral data and 1D NOE experiment, the main structural element of these preparations was found to be a regularly substituted polyoxyethylene, namely poly[3-(3,4-dihydroxyenyl)glyceric acid] (PDPGA) or poly[oxy-1-carboxy-2-(3,4-dihydroxyphenyl)ethylene]. Such caffeic acid-derived biopolymer to our knowledge has not been known and has been identified for the first time. This compound represents a new class of natural polyethers with a residue of 3-(3,4-dihydroxyphenyl)glyceric acid as the repeating unit. Most of the carboxylic groups of PDPGA from A. italica unlike the polymer of S. asperum, S. caucasicum, and S. officinale are methylated. The 2D DOSY experiment gave the similar diffusion coefficient for the methylated and non-methylated signals of A. italica PDPGA. Both sets of signals fell in the same horizontal. This would imply a similar molecular weight for methylated and non-methylated polymers. This was further evidenced by graphic representations of the intensity decay of the 1H signals of aromatic H-2″ and H-1 at δ 7.16 and 5.24 and that of the methoxy group at δ 3.85. These three signals essentially showed the same curve shape. According to results of in vitro and in vivo experiments PDPGA of S.asperum and S.caucasicum could be considered as potential anti-inflammatory, wound healing and anti-cancer therapeutic agent.

Keywords: caffeic acid-derived polyether, poly[3-(3, 4-dihydroxyphenyl)glyceric acid], poly[oxy-1-carboxy-2-(3, 4-dihydroxyphenyl)ethylene], symphytum, anchusa

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Authors: Kishor C. Poria, Deepak Adroja, Arvind Bajaj

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During the last few decades, the growth of single crystals has attained enormous importance for both academic research and technology. Single crystals are pillars of modern technology. In recent emerging trends of photonics and optoelectronics technology, there has been increased need for organic and semi organic materials for Non-Linear Optical (NLO) applications. The paper dealt with the initiation of good single crystals of thiourea and metal doped thiourea. The authors have successfully grown thiourea (pure) and metal doped thiourea crystals using relatively simple and inexpensive slow evaporation of aqueous solution technique. Pure thiourea crystals were grown with different light intensities and frequencies as there growth conditions. Metals (Cu, Co, Ni, Fe) doped crystals were grown using a simple evaporation technique. The paper explains growth methods and associated grown parameters in detail. The average size of the crystal is varied in size from 40 mm x 1mm to 1.5 mm x 1.5 mm to 0.5 mm. Crystals obtained are hexagonal, tetragonal, and rectangular in shape with different optical qualities. All grown crystals are characterized using X-Ray Diffraction Analysis (XRD), Ultra Violet Visible analysis, and Fourier Transform Infrared Spectrometry. Their non-linear optical characteristics were determined by Second Harmonic Generation (SHG) and their Laser Dispersive analysis. The grown crystals are characterized using Nd:YAG laser and the highest conversion efficiency of the signal pass light are calculated. It shows 58 % of standard values for KDP crystals. All results are summarized in this work.

Keywords: crystal, metal-doped thiourea, non-linear optical, NLO, thiourea

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Authors: Mohammed Abdulhameed, Sagir M. Abdullahi

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In this paper, based on the applications of nanoparticle, the blood flow along with nanoparticles through stenosed artery is studied. The blood is acted by periodic body acceleration, an oscillating pressure gradient and an external magnetic field. The mathematical formulation is based on Caputo-Fabrizio fractional derivative without singular kernel. The model of ordinary blood, corresponding to time-derivatives of integer order, is obtained as a limiting case. Analytical solutions of the blood velocity and temperature distribution are obtained by means of the Hankel and Laplace transforms. Effects of the order of Caputo-Fabrizio time-fractional derivatives and three different nanoparticles i.e. Fe3O4, TiO4 and Cu are studied. The results highlights that, models with fractional derivatives bring significant differences compared to the ordinary model. It is observed that the addition of Fe3O4 nanoparticle reduced the resistance impedance of the blood flow and temperature distribution through bell shape stenosed arteries as compared to TiO4 and Cu nanoparticles. On entering in the stenosed area, blood temperature increases slightly, but, increases considerably and reaches its maximum value in the stenosis throat. The shears stress has variation from a constant in the area without stenosis and higher in the layers located far to the longitudinal axis of the artery. This fact can be an important for some clinical applications in therapeutic procedures.

Keywords: nanoparticles, blood flow, stenosed artery, mathematical models

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Authors: Safwat Mohamed, Rasha Metawi, Hadeel Khalil, Hussein Kamal

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This paper discusses and reveals the manufacturing techniques of the leather scale armour of Tutankhamun. This armour was in critical condition and went under many conservation procedures as it suffered from some serious deterioration aspects including fragmentation. In addition, its original shape was lost, the leather scales were found scattered in the box and separated from the linen basis, and hence its outlines were blurred and incomprehensible. In view of this, the leather scale armour of Tutankhamun was desperate for urgent conservation and reconstruction interventions. Documentation measures were done before conservation. Several re-treatable conservation procedures were applied seeking for stabilizing the armour and reaching sustainable condition. The conservation treatments included many investigations and analyses that helped in revealing materials and techniques of making the armour. The leather scale armour of Tutankhamun consisted of leather scales attached to a linen support. This linen support consisted of several layers. Howard Carter assumed that the linen support consisted of 6 layers. The undertaken conservation treatments helped in revealing the actual number of layers of the linen support as well as in reaching the most sustainable condition. This paper views the importance of the conservation procedures, which were recently carried out on Tutankhamun’s leather scale armour, in identifying and revealing all materials and techniques used in its manufacturing. The collected data about manufacturing techniques were used in making a replica of the leather scale armour with the same methods and materials.

Keywords: leather scales armours, conservation, manufacturing techniques, Tutankhamun, producing a replica

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Authors: T. Yu, L. Audibert, J. F. Chaix, D. Komatitsch, V. Garnier, J. M. Henault

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Linear Ultrasonic Techniques play a major role in Non-Destructive Evaluation (NDE) for civil engineering structures in concrete since they can meet operational requirements. Interpretation of ultrasonic measurements could be improved by a better understanding of ultrasonic wave propagation in a multiple scattering medium. This work aims to develop a 2D numerical model of ultrasonic wave propagation in a heterogeneous medium, like concrete, integrating the multiple scattering phenomena in SPECFEM software. The coherent field of multiple scattering is obtained by averaging numerical wave fields, and it is used to determine the effective phase velocity and attenuation corresponding to an equivalent homogeneous medium. First, this model is applied to one scattering element (a cylinder) in a homogenous medium in a linear-elastic system, and its validation is completed thanks to the comparison with analytical solution. Then, some cases of multiple scattering by a set of randomly located cylinders or polygons are simulated to perform parametric studies on the influence of frequency and scatterer size, concentration, and shape. Also, the effective properties are compared with the predictions of Waterman-Truell model to verify its validity. Finally, the mortar viscoelastic behavior is introduced in the simulation in order to considerer the dispersion and the attenuation due to porosity included in the cement paste. In the future, different steps will be developed: The comparisons with experimental results, the interpretation of NDE measurements, and the optimization of NDE parameters before an auscultation.

Keywords: attenuation, multiple-scattering medium, numerical modeling, phase velocity, ultrasonic measurements

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Authors: Thi Thao Ninh, Yuri Trusov, José Ramón Botella

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Heterotrimeric G proteins, comprised of three subunits, α, β and γ, are involved in signal transduction pathways that mediate a vast number of processes across the eukaryotic kingdom. 23 Gα subunits are present in humans whereas most plant genomes encode for only one canonical Gα. The disparity observed between Arabidopsis, rice, and maize Gα-deficient mutant phenotypes suggest that Gα functions have diversified between eudicots and monocots during evolution. Alternatively, since the only Gα mutations available in dicots have been produced in Arabidopsis, the possibility exists that this species might be an exception to the rule. In order to test this hypothesis, we studied the G protein α subunit (TGA1) in tomato. Four tga1 knockout lines were generated in tomato cultivar Moneymaker using CRISPR/Cas9. The tga1 mutants exhibit a number of auxin-related phenotypes including changes in leaf shape, reduced plant height, fruit size and number of seeds per fruit. In addition, tga1 mutants have increased sensitivity to abscisic acid during seed germination, reduced sensitivity to exogenous auxin during adventitious root formation from cotyledons and excised hypocotyl explants. Our results suggest that Gα mutant phenotypes in tomato are very similar to those observed in monocots, i.e. rice and maize, and cast doubts about the validity of using Arabidopsis as a model system for plant G protein studies.

Keywords: auxin-related phenotypes, CRISPR/Cas9, G protein α subunit, heterotrimeric G proteins, tomato

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Authors: Pooja Ahuja, Tejal Bhutani, M. S. Dahiya

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Cheiloscopy, the study of lip prints, is a tool in forensic investigation technique that deals with identification of individuals based on lips patterns. The objective of this study is to determine predominant lip print pattern found among the Gujarati population, to evaluate whether any sex difference exists and to study the permanence of the pattern over six months duration. The study comprised of 100 healthy individuals (50 males and 50 females), in the age group of 18 to 25 years of Gujarati population of the Gandhinagar region of the Gujarat state, India. By using Suzuki and Tsuchihashi classification, Lip prints were then divided into four quadrants and also classified on the basis of peripheral shape of the lips. Materials used to record the lip prints were dark brown colored lipstick, cellophane tape, and white bond paper. Lipstick was applied uniformly, and lip prints were taken on the glued portion of cellophane tape and then stuck on to a white bond paper. These lip prints were analyzed with magnifying lens and virtually with stereo microscope. On the analysis of the subject population, results showed Branched pattern Type II (29.57 percentage) to be most predominant in the Gujarati population. Branched pattern Type II (35.60 percentage) and long vertical Type I (28.28 percentage) were most prevalent in males and females respectively and large full lips were most predominantly present in both the sexes. The study concludes that lip prints in any form can be an effective tool for identification of an individual in a closed or open group forms.

Keywords: cheiloscopy, lip pattern, predomianant, Gujarati population

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Authors: Abdoon A.S., El Ashkar E.A., Kandil O.M., Wael H. Eisa, Shaban A.M., Khaled H.M., El Ashkar M.R., El Shaer M., Hussein H., Shaalan A.H., El Sayed M.

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Cancer is a major obstacle to human health and development worldwide. Conventional strategies for cancer intervention include surgery, chemotherapy, and radiation therapy. Recently, plasmon photothermal therapy (PPTT) was introduced as a promising treatment for the management of cancer and several non-cancerous diseases that are generally characterized by overgrowth of abnormal cells. The present work was conducted to evaluate the cytotoxic efficacy and toxicity of gold nanorods (AuNRs) in dogs and cats suffering from spontaneous mammary gland. AuNRs was injected intratumoral (IT, n=10, dose of 75 p.p.m/kg body weight) or by using spray method after surgical removal of cancer tissue (n=2) in dogs and cats. Then exposed to laser light after 60 min. Treated animals were observed every 2 days and the morphological changes in tumor size and shape were recorded. Blood samples were collected before and after treatment for checking CBC, liver and kidney functions. Results revealed that AuNRs successfully treat mammary gland tumor in dogs and cats (adenocarcinoma type 1 to IV). AuNRs induced sloughing of carcinogenic tissue within 5 to 15 days. AuNRs have no toxic effect on blood profile and the toxicity studies still under evaluation. Conclusion, AuNRs can be used for treatment of mammary gland carcinoma in dogs and cats.

Keywords: pet animals, mammary gland tumor, AuNRs, photothermal therapy, toxicity studies

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Authors: R. Lhissou , A. El Harti , K. Chokmani, E. Bachaoui, A. El Ghmari

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Soil salinity is a serious environmental hazard in many countries around the world especially the arid and semi-arid countries like Morocco. Salinization causes negative effects on the ground; it affects agricultural production, infrastructure, water resources and biodiversity. Remote sensing can provide soil salinity information for large areas, and in a relatively short time. In addition, remote sensing is not limited by extremes in terrain or hazardous condition. Contrariwise, experimental methods for monitoring soil salinity by direct measurements in situ are very demanding of time and resources, and also very limited in spatial coverage. In the irrigated perimeter of Tadla plain in central Morocco, the increased use of saline groundwater and surface water, coupled with agricultural intensification leads to the deterioration of soil quality especially by salinization. In this study, we assessed several spectral indices of soil salinity cited in the literature using Landsat TM satellite images and field measurements of electrical conductivity (EC). Three Landsat TM satellite images were taken during 3 months in the dry season (September, October and November 2011). Based on field measurement data of EC collected in three field campaigns over the three dates simultaneously with acquisition dates of Landsat TM satellite images, a two assessment techniques are used to validate a soil salinity spectral indices. Firstly, the spectral indices are validated locally by pixel. The second validation technique is made using a window of size 3x3 pixels. The results of the study indicated that the second technique provides getting a more accurate validation and the assessment has shown its limits when it comes to assess across the pixel. In addition, the EC values measured from field have a good correlation with some spectral indices derived from Landsat TM data and the best results show an r² of 0.88, 0.79 and 0.65 for Salinity Index (SI) in the three dates respectively. The results have shown the usefulness of spectral indices as an auxiliary variable in the spatial estimation and mapping salinity in irrigated land.

Keywords: remote sensing, spectral indices, soil salinity, irrigated land

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Authors: Greg Fetzer

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One of the fundamental tensions of creative work is between the need to be passionate and persistent in advancing novel and risky ideas and the need to be flexible, revising, or even abandoning ideas in favor of others. The tension becomes fraught in part because of the attachment that creators have toward their ideas. Idea attachment is defined here as a multifaceted concept referring to affection, passion, and connection toward a target—in this case, one’s projects or ideas. Yet feeling attached can make creators resistant to feedback, making them less flexible and leading them to escalate commitment. Despite a growing understanding of how attachment develops and evolves in response to project changes, feedback, and creative jolts, we still know relatively little about the organizational dynamics that may shape idea attachment. Through a qualitative, inductive study of early-stage R&D scientists in the pharmaceutical industry, this research finds that scientists develop bounded attachment, a mindset that limits emotional attachment to ideas while still fostering engagement in idea development. This research develops a process model of how bounded attachment is developed and enacted across three stages of the creative process, idea generation, idea evaluation, and outcome assessment, as well as the role that organizational practices and professional identity play in shaping this process: these collective practices provided structures to ensure ideas were evaluated in a rational (i.e. non-emotional way) while also providing socioemotional support in the face of setbacks. Together, this process led to continued creative engagement across ideas in a portfolio and helped scientists construct a sense of meaningful work despite a high likelihood (and frequency) of failure.

Keywords: creativity, innovation, organizational practices, qualitative, attachment

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Authors: Geetika Barman, B. S. Daya Sagar

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In this article, we proposed a pixel-wise classification of hyperspectral images using a mathematical morphology operator-based distance metric called “dilation distance” and “erosion distance”. This method involves measuring the spatial distance between the spectral features of a hyperspectral image across the bands. The key concept of the proposed approach is that the “dilation distance” is the maximum distance a pixel can be moved without changing its classification, whereas the “erosion distance” is the maximum distance that a pixel can be moved before changing its classification. The spectral signature of the hyperspectral image carries unique class information and shape for each class. This article demonstrates how easily the dilation and erosion distance can measure spatial distance compared to other approaches. This property is used to calculate the spatial distance between hyperspectral image feature vectors across the bands. The dissimilarity matrix is then constructed using both measures extracted from the feature spaces. The measured distance metric is used to distinguish between the spectral features of various classes and precisely distinguish between each class. This is illustrated using both toy data and real datasets. Furthermore, we investigated the role of flat vs. non-flat structuring elements in capturing the spatial features of each class in the hyperspectral image. In order to validate, we compared the proposed approach to other existing methods and demonstrated empirically that mathematical operator-based distance metric classification provided competitive results and outperformed some of them.

Keywords: dilation distance, erosion distance, hyperspectral image classification, mathematical morphology

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Authors: A. Giannakopoulos, S. B. Buckley

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Problem solving in any field is recognised as a prerequisite for any advancement in knowledge. For example in South Africa it is one of the seven critical outcomes of education together with critical thinking. As a systematic way to problem solving was initiated in mathematics by the great mathematician George Polya (the father of problem solving), more detailed and comprehensive ways in problem solving have been developed. This paper is based on the findings by the author and subsequent recommendations for further research in problem solving and critical thinking. Although the study was done in mathematics, there is no doubt by now in almost anyone’s mind that mathematics is involved to a greater or a lesser extent in all fields, from symbols, to variables, to equations, to logic, to critical thinking. Therefore it stands to reason that mathematical principles and learning cannot be divorced from any field. In management of knowledge situations, the types of problems are similar to mathematics problems varying from simple to analogical to complex; from well-structured to ill-structured problems. While simple problems could be solved by employees by adhering to prescribed sequential steps (the process), analogical and complex problems cannot be proceduralised and that diminishes the capacity of the organisation of knowledge creation and innovation. The low efficiency in some organisations and the low pass rates in mathematics prompted the author to view problem solving as a product. The authors argue that using mathematical approaches to knowledge management problem solving and treating problem solving as a product will empower the employee through further training to tackle analogical and complex problems. The question the authors asked was: If it is true that problem solving and critical thinking are indeed basic skills necessary for advancement of knowledge why is there so little literature of knowledge management (KM) about them and how they are connected and advance KM?This paper concludes with a conceptual model which is based on general accepted principles of knowledge acquisition (developing a learning organisation), knowledge creation, sharing, disseminating and storing thereof, the five pillars of knowledge management (KM). This model, also expands on Gray’s framework on KM practices and problem solving and opens the doors to a new approach to training employees in general and domain specific areas problems which can be adapted in any type of organisation.

Keywords: critical thinking, knowledge management, mathematics, problem solving

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Authors: Panatda Intanin, Sangutid Thongsawad, Chirapha Tannanonta, Todsaporn Fuangrod

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Stereotactic radiosurgery (SRS) is a highly precision delivery technique that requires comprehensive quality assurance (QA) tests prior to treatment delivery. An isocenter of delivery beam plays a critical role that affect the treatment accuracy. The uncertainty of isocenter is traditionally accessed using circular cone equipment, Winston-Lutz (WL) phantom and film. This technique is considered time consuming and highly dependent on the observer. In this work, the development of multileaf collimator (MLC)-based isocenter verification tool using electronic portal imaging device (EPID) was proposed and evaluated. A mechanical isocenter alignment with ball bearing diameter 5 mm and circular cone diameter 10 mm fixed to gantry head defines the radiation field was set as the conventional WL test method. The conventional setup was to compare to the proposed setup; using MLC (10 x 10 mm) to define the radiation filed instead of cone. This represents more realistic delivery field than using circular cone equipment. The acquisition from electronic portal imaging device (EPID) and radiographic film were performed in both experiments. The gantry angles were set as following: 0°, 90°, 180° and 270°. A software tool was in-house developed using MATLAB/SIMULINK programming to determine the centroid of radiation field and shadow of WL phantom automatically. This presents higher accuracy than manual measurement. The deviation between centroid of both cone-based and MLC-based WL tests were quantified. To compare between film and EPID image, the deviation for all gantry angle was 0.26±0.19mm and 0.43±0.30 for cone-based and MLC-based WL tests. For the absolute deviation calculation on EPID images between cone and MLC-based WL test was 0.59±0.28 mm and the absolute deviation on film images was 0.14±0.13 mm. Therefore, the MLC-based isocenter verification using EPID present high sensitivity tool for SRS QA.

Keywords: isocenter verification, quality assurance, EPID, SRS

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Authors: Mogens Saberi

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The focus of this article is to present the experience gained from the design of a grouted pile-sleeve connection and to present simple design expressions which can be used in the preliminary design phase of such connections. The grout pile-sleeve connection serves as a connection between an offshore jacket foundation and pre-installed piles located in the seabed. The jacket foundation supports a wind turbine generator resulting in significant dynamic loads on the connection. The connection is designed with shear keys in order to optimize the overall design but little experience is currently available in the use of shear keys in such connections. It is found that the consequence of introducing shear keys in the design is a very complex stress distribution which requires special attention due to significant fatigue loads. An optimal geometrical shape of the shear keys is introduced in order to avoid large stress concentration factors and a relatively easy fabrication. The connection is analysed in ANSYS Mechanical where the grout is modelled by a non-linear material model which allows for cracking of the grout material and captures the elastic-plastic behaviour of the grout material. Special types of finite elements are used in the interface between the pile sleeve and the grout material to model the slip surface between the grout material and the steel. Based on the performed finite element modelling simple design expressions are introduced.

Keywords: fatigue design, non-linear finite element modelling, structural dynamics, simple design expressions

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Authors: Dwi Retno Sri Ambarwati

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Recently, the traditional architecture were getting lost, replaced by modern architecture. The existence of many traditional houses often changing the function and change the values in an effort to adjust to the modern lifestyle, whereas the spiritual background of traditional architectural design is very specific and be the basis for consideration in the construction of the building, both in terms of determining the location of the building, the direction toward building, the spatial pattern and organization of space, zoning, hierarchical space, building form, ornamentation, the selection of building materials, and so on. The changes in function and form will transformed the spiritual values contained in it, because the architecture affects human behavior and reflects the culture. The traditional architecture views the architecture as a concept that has different tendencies in terms of orientation, shape, and attitude toward nature that tends to harmony with the social environment and local culture. The concept of the spirit of place made the architecture looks familiar, not arrogant and give a positive value to the surrounding environment. Every culture has a traditional architecture that full of spiritual values, although in the simplest form. Humans can learn about human values and local wisdom through the positive values that contained in traditional architecture, the desire to balance themselves with nature and the environment, not overbearing, strict adherence to the prevailing norms, openness in public life and intimacy family life that form a harmonious in life. The great and the wise value of traditional architecture should be revived in modern architecture that tends to ignore the spiritual values and more concerned with the functional and aesthetic pleasure, by combining the noble values of traditional architecture into modern architecture.

Keywords: architecture, combining noble values, local wisdom, traditional architecture

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Authors: Alireza Gholipour, Mergen H. Ghayesh, Anthony Zander, Stephen J. Nicholls, Peter J. Psaltis

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A three-dimensional numerical model of an atherosclerotic coronary ‎artery is developed for the determination of high-risk situation and ‎hence heart attack prediction. Employing the finite element method ‎‎(FEM) using ANSYS, fluid-structure interaction (FSI) model of the ‎artery is constructed to determine the shear stress distribution as well ‎as the von Mises stress field. A flexible model for an atherosclerotic ‎coronary artery conveying pulsatile blood is developed incorporating ‎three-dimensionality, artery’s tapered shape via a linear function for ‎artery wall distribution, motion of the artery, blood viscosity via the ‎non-Newtonian flow theory, blood pulsation via use of one-period ‎heartbeat, hyperelasticity via the Mooney-Rivlin model, viscoelasticity ‎via the Prony series shear relaxation scheme, and micro-calcification ‎inside the plaque. The material properties used to relate the stress field ‎to the strain field have been extracted from clinical data from previous ‎in-vitro studies. The determined stress fields has potential to be used as ‎a predictive tool for plaque rupture and dissection.‎ The results show that stress concentration due to micro-calcification ‎increases the von Mises stress significantly; chance of developing a ‎crack inside the plaque increases. Moreover, the blood pulsation varies ‎the stress distribution substantially for some cases.‎

Keywords: atherosclerosis, fluid-structure interaction‎, coronary arteries‎, pulsatile flow

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Authors: Soumendu Monia, Vaibhav Jain, Hrishikesh Jugade, Manashi Adhikary, Goutam Mukhopadhyay

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'Rolled in scale' (RIS) and 'Rolled in Scum' (RISc) are two superficial surface defects on cold rolled and annealed steel sheets which affect the aesthetics of surface and thereby that of the end-product. Both the defects are believed to be originating from distinctly different sources having different mechanisms of formation. However, due to their similar physical appearance, RIS and RISc are generally confused with each other and hence attaining the exact root cause for elimination of the defect becomes difficult. RIS appears irregular in shape, sometimes scattered, and always oriented in rolling direction. RISc is generally oval shaped, having identifiable pointed edges and mostly oriented in rolling direction. Visually, RIS appears to be greyish in colour whereas RISc is whitish in colour. Both the defects have quite random occurrence and do not leave any imprints on the reverse-side of the sheet. In the current study, an attempt has been made to differentiate these two similar looking surface defects using various metallographic and characterization techniques. Systematic experiments have been carried out to identify possible mechanisms of formation of these defects. Detailed characterization revealed basic differences between RIS and RISc with respect to their surface morphology. To summarize, RIS was observed as a residue of an otherwise under-pickled scale patch on surface, after it has been subjected to cold rolling and annealing in a batch/continuous furnace. Whereas RISc was found to be a localized rubbing of the surface, at the time of cold rolling itself, resulting in a rough surface texture.

Keywords: annealing, rolled in scale, rolled in scum, skin panel

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Authors: Ying Sun, Yuxuan Lei

Abstract:

Based on the analysis of the current situation of Nantong's comprehensive transportation system, the interactive relationship between the transportation system and the economy and society is clarified, and then the development strategy for the planning and implementation of the "three ports in one" comprehensive transportation system of ocean, land, and airport is proposed for this round of territorial spatial planning. The research findings are as follows: (1) The comprehensive transportation network system of Nantong City is beginning to take shape, but the lack of a unified and complete system planning makes it difficult to establish a "multi-port integration" pattern with transportation hubs. (2) At the Yangtze River Delta level and Nantong City level, a connected transport node integrating ocean, land, and airport should be built in the transportation construction planning to effectively meet the guidance of the overall territorial space planning of Nantong City. (3) Nantong's comprehensive transportation system and economic society have experienced three interactive development relations in different stages: mutual promotion, geographical separation, and high-level driving. Therefore, the current planning of Nantong's comprehensive transportation system needs to be optimized. The four levels of Nantong city, Shanghai metropolitan area, Yangtze River Delta, and each district, county, and city should be comprehensively considered, and the four development strategies of accelerating construction, dislocation development, active docking, and innovative implementation should be adopted.

Keywords: master plan for territorial space, Integrated transportation system, Nantong, sea, land and air, "Three ports in one"

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Authors: S. Shankar Bharathi

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Inspection of surface defects on metallic components has always been challenging due to its specular property. Occurrences of defects such as scratches, rust, pitting are very common in metallic surfaces during the manufacturing process. These defects if unchecked can hamper the performance and reduce the life time of such component. Many of the conventional image processing algorithms in detecting the surface defects generally involve segmentation techniques, based on thresholding, edge detection, watershed segmentation and textural segmentation. They later employ other suitable algorithms based on morphology, region growing, shape analysis, neural networks for classification purpose. In this paper the work has been focused only towards detecting scratches. Global and other thresholding techniques were used to extract the defects, but it proved to be inaccurate in extracting the defects alone. However, this paper does not focus on comparison of different segmentation techniques, but rather describes a novel approach towards segmentation combined with hausdorff dilation distance. The proposed algorithm is based on the distribution of the intensity levels, that is, whether a certain gray level is concentrated or evenly distributed. The algorithm is based on extraction of such concentrated pixels. Defective images showed higher level of concentration of some gray level, whereas in non-defective image, there seemed to be no concentration, but were evenly distributed. This formed the basis in detecting the defects in the proposed algorithm. Hausdorff dilation distance based on mathematical morphology was used to strengthen the segmentation of the defects.

Keywords: metallic surface, scratches, segmentation, hausdorff dilation distance, machine vision

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Authors: Mohsen Akhlaghi, Tahereh Ebrahimi

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Pricing strategy is a vital component in achieving the balance between customer value and business profitability. The aim of this study is to provide insights into the factors, techniques, and approaches involved in pricing decisions. The study utilizes a descriptive approach to discuss various aspects of pricing strategy in marketing, drawing on concepts from market research, consumer psychology, competitive analysis, and adaptability. This approach presents a comprehensive view of pricing decisions. The result of this exploration is a framework that highlights key factors influencing pricing decisions. The study examines how factors such as market positioning, product differentiation, and brand image shape pricing strategies. Additionally, it emphasizes the role of consumer psychology in understanding price elasticity, perceived value, and price-quality associations that influence consumer behavior. Various pricing techniques, including charm pricing, prestige pricing, and bundle pricing, are mentioned as methods to enhance sales by influencing consumer perceptions. The study also underscores the importance of adaptability in responding to market dynamics through regular price monitoring, dynamic pricing, and promotional strategies. It recognizes the role of digital platforms in enabling personalized pricing and dynamic pricing models. In conclusion, the study emphasizes that effective pricing strategies strike a balance between customer value and business profitability, ultimately driving sales, enhancing brand perception, and fostering lasting customer relationships.

Keywords: business, customer benefits, marketing, pricing

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Authors: Zelalem Fantahun

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Part-of-speech tagging is the process of assigning a part-of-speech or other lexical class marker to each word into naturally occurring text. Part-of-speech tagging is the most fundamental and basic task almost in all natural language processing. In natural language processing, the problem of providing large amount of manually annotated data is a knowledge acquisition bottleneck. Since, Amharic is one of under-resourced language, the availability of tagged corpus is the bottleneck problem for natural language processing especially for POS tagging. A promising direction to tackle this problem is to provide a system that does not require manually tagged data. In unsupervised learning, the learner is not provided with classifications. Unsupervised algorithms seek out similarity between pieces of data in order to determine whether they can be characterized as forming a group. This paper explicates the development of unsupervised part-of-speech tagger using K-Means clustering for Amharic language since large amount of data is produced in day-to-day activities. In the development of the tagger, the following procedures are followed. First, the unlabeled data (raw text) is divided into 10 folds and tokenization phase takes place; at this level, the raw text is chunked at sentence level and then into words. The second phase is feature extraction which includes word frequency, syntactic and morphological features of a word. The third phase is clustering. Among different clustering algorithms, K-means is selected and implemented in this study that brings group of similar words together. The fourth phase is mapping, which deals with looking at each cluster carefully and the most common tag is assigned to a group. This study finds out two features that are capable of distinguishing one part-of-speech from others these are morphological feature and positional information and show that it is possible to use unsupervised learning for Amharic POS tagging. In order to increase performance of the unsupervised part-of-speech tagger, there is a need to incorporate other features that are not included in this study, such as semantic related information. Finally, based on experimental result, the performance of the system achieves a maximum of 81% accuracy.

Keywords: POS tagging, Amharic, unsupervised learning, k-means

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Authors: Dalila Lino, Maria Joao Hortas, Carla Rocha, Clarisse Nunes, Natalia Vieira, Marina Fuertes, Kátia Sa

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The value of play is recognized worldwide and is considered a fundamental right of all children, as defined in Article 31 of the United Nations Children’s Rights. It is consensual among the scientific community that play, and toys are of vital importance for children’s learning and development. Play promotes the acquisition of language, enhances creativity and improves social, affective, emotional, cognitive and motor development of young children. Young children ages 0 to 6 who have had many opportunities to get involved in play show greater competence to adapt to new and unexpected situations and more easily overcome the pain and suffering caused by traumatic situations. The PlayTrain Project aims to understand the places/spaces of play in the education of children from 0 to 6 years and promoting the training of preschool teachers to become capable of developing practices that enhance children’s agency, experimentation in the physical and social world and the development of imagination and creativity. This project follows the Design-Based-Research (DBR) and has two dimensions: research and intervention. The participants are 120 students from the Master in Pre-school Education of the Higher School of Education, Polytechnic Institute of Lisbon enrolled in the academic year 2018/2019. The development of workshops focused on the role of play and toys for young children’s learning promotes the participants reflection and the development of skills and knowledge to construct developmentally appropriated practices in early childhood education. Data was collected through an online questionnaire and focal groups. Results show that the PlayTrain Project contribute to the development of a body of knowledge about the role of play for early childhood education. It was possible to identify the needs of preschool teacher education and to enhance the discussion among the scientific and academic community about the importance of deepening the role of play and toys in the study plans of the masters in pre-school education.

Keywords: children's learning, early childhood education, play, teacher education, toys

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Authors: Vincent Mokoka, Kai Behn, Edwin Mudongo, Jan Ruppert, Kingsley Ayisi, Anja Linstädter

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Severe drought may trigger a transition of vegetation composition in dryland grasslands, with productive perennial grasses often being replaced by annual grasses. Grazing pressure is thought to exacerbate drought effects, but little is known on the joint effects of grazing and drought on the functional and taxonomic composition of the herbaceous vegetation in African savannas. This study thus aimed to elucidate which herbaceous species and plant functional types (PFTs) are most resistant to prolonged drought and grazing and whether resting plays a role in this context. Thus, we performed a six-year field experiment in South Africa’s Limpopo province, combining drought and grazing treatments. Aboveground herbaceous biomass was harvested annually and separated into species. We grouped species into five PFTs, i.e. very broad-leaved perennial grasses, broad-leaved perennial grasses, narrow-leaved perennial grasses, annual grasses, and forbs. For all species, we also recorded three-leaf traits (leaf area - LA, specific leaf area – SLA, and leaf dry matter content – LDM) to describe their resource acquisition strategies. We used generalized linear models to test for treatment effects and their interaction. Association indices were used to detect the relationship between species and treatments. We found that there were no absolute winner species or PFTs, as the six-year severe drought had a pronounced negative impact on the biomass production of all species and PFTs. However, we detected relative winners with increases in relative abundances, mainly forbs and less palatable narrow-leafed grasses with comparatively low LA and high LDMC, such as Aristida stipidata Hack. These species and PFTs also tended to be favored by grazing. Although few species profited from resting, for most species, the combination of drought and resting proved to be particularly unfavorable. Winners and losers can indicate ecological transition and may be used to guide management decisions.

Keywords: aboveground net primary production, drought, functional diversity, winner and loser species

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Authors: Akbar Esmaeili, Zahra Salarieh

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Cerium oxide nanoparticles (nano-series) are used as catalysts in industrial applications due to their free radical scavenging properties. Given that free radicals play an essential role in the pathology of many neurological diseases, we investigated the use of nanocrystals as a potential therapeutic agent for oxidative damage. This project synthesized nano-series from a new and environmentally friendly bio-pathway. Investigation of cerium nitrate in culture medium containing inoculated Lactobacillus acidophilus strain before incubation produces nano-series. Loaded with glatiramer acetate (GA) was formed by coating carboxymethylcellulose (CMC) and CeO2. FE-SEM analysis showed nano-series in the 9-11 nm range, spherical shape, and uniform particle size distribution. Cubic nanoparticles containing anti-multiple sclerosis (anti-Ms) treatment called GA were used. Glycerol monostearate (GMS) was used as a fat base, and evening primrose extract was used as an anti-inflammatory in cubosomes. Design-Expert® software was used to study the effects of different formulation factors on the properties of GAloaded cubic dispersions. Thirty GA-labeled cubic dispersions were prepared with GA-labeled carboxymethylcellulose and evaluated in vitro. The results showed an average nano-series size of 89.02 and a zeta potential of -49.9. Cubosomes containing GA-CMC/CeO2 showed a stable release profile for 180 min. The results showed that cubosomes containing GA-CMC/CeO2 could be a promising drug carrier with normal release behavior.

Keywords: ciochemistry, biotechnology, molecular, biology

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Authors: S. Djaziri, F. Sket, A. Hynowska, S. Milenkovic

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The use of Fe-Al based intermetallics as an alternative to Cr/Ni based stainless steels is very promising for industrial applications that use critical raw materials parts under extreme conditions. However, the development of advanced Fe-Al based intermetallics with appropriate mechanical properties presents several challenges that involve appropriate processing and microstructure control. A processing strategy is being developed which aims at producing a net-shape porous Fe-based preform that is infiltrated with molten Al or Al-alloy. In the present work, porous Fe-based preforms produced by two different methods (selective laser melting (SLM) and Kochanek-process (KE)) are studied during infiltration with molten aluminum. In the objective to elucidate the mechanisms underlying the formation of Fe-Al intermetallic phases during infiltration, an in-house furnace has been designed for in situ observation of infiltration at synchrotron facilities combining x-ray radiography (XR) and x-ray diffraction (XRD) techniques. The feasibility of this approach has been demonstrated, and information about the melt flow front propagation has been obtained. In addition, reactive infiltration has been achieved where a bi-phased intermetallic layer has been identified to be formed between the solid Fe and liquid Al. In particular, a tongue-like Fe₂Al₅ phase adhering to the Fe and a needle-like Fe₄Al₁₃ phase adhering to the Al were observed. The growth of the intermetallic compound was found to be dependent on the temperature gradient present along the preform as well as on the reaction time which will be discussed in view of the different obtained results.

Keywords: combined synchrotron radiography and diffraction, Fe-Al intermetallic compounds, in-situ molten Al infiltration, porous solid Fe preforms

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Authors: Hsi Wei

Abstract:

Does the language we speak affect the way we think? This question has been discussed for a long time from different aspects. In this article, the issue is examined with an experiment on how speakers of different languages tend to do different sequencing when it comes to the size of general objects. An essential difference between the usage of English and Mandarin is the way we sequence the size of places or objects. In English, when describing the location of something we may say, for example, ‘The pen is inside the trashcan next to the tree at the park.’ In Mandarin, however, we would say, ‘The pen is at the park next to the tree inside the trashcan.’ It’s clear that generally English use the sequence of small to big while Mandarin the opposite. Therefore, the experiment was conducted to test if the difference of the languages affects the speakers’ ability to do the different sequencing. There were two groups of subjects; one consisted of English native speakers, another of Mandarin native speakers. Within the experiment, three nouns were showed as a group to the subjects as their native languages. Before they saw the nouns, they would first get an instruction of ‘big to small’, ‘small to big’, or ‘repeat’. Therefore, the subjects had to sequence the following group of nouns as the instruction they get or simply repeat the nouns. After completing every sequencing and repetition in their minds, they pushed a button as reaction. The repetition design was to gather the mere reading time of the person. As the result of the experiment showed, English native speakers reacted more quickly to the sequencing of ‘small to big’; on the other hand, Mandarin native speakers reacted more quickly to the sequence ‘big to small’. To conclude, this study may be of importance as a support for linguistic relativism that the language we speak do shape the way we think.

Keywords: language, linguistic relativism, size, sequencing

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

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

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

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