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Genial tubercles: Morphological study of the controversial anatomical landmark using cone beam computed tomography

World Journal of Radiology 2019年第7期11卷 94-101页

作者： Yasser A Araby Ahmed A Alhirabi Abdelaleem H Santawy Department of Prosthetic Dental Sciences College of DentistryQassim UniversityQassim 51452Saudi Arabia Dental Intern College of DentistryQassim UniversityQassim 51452Saudi Arabia Department of Maxillofacial Surgery and Diagnostic Sciences College of DentistryQassim UniversityQassim 51452Saudi Arabia

BACKGROUND Identification of the morphology of the genial tubercles (GTs) is valuable for different dental applications. The morphological pattern of the GTs is still controversial, and therefore, the study of its morphology using cone beam computed tomography (CBCT) plays a valuable role in resolving the controversy. AIM To assess the morphological pattern, dimensions and position of the GTs using CBCT among a selected Saudi population. METHODS CBCT records of 155 Saudi subjects (49 female and 106 male) were used to assess the pattern and size of the GTs and to determine the distance from the apices of the lower central incisors to the superior border of the incisors (I-SGT) and the distance from the inferior border of the GTs to the menton (IGT-M). RESULTS The results of this study showed that the most common morphological pattern was of two superior GTs and a rough impression below them (36.8%), followed by two superior GTs and a median ridge representing fused inferior GTs below them (22.6%) and a single median eminence or projection (20%). The classically described pattern, of two superior and two inferior GTs placed one above the other, was found in only 14.2% of cases, while 6.4% of the studied cases had no GTs. The mean width and height were 6.23 ± 1.93 mm and 6.67 ± 3.04 mm, respectively, while the mean I-SGT and IGT-M measurements were 8.26 ± 2.7 mm and 8.13 ± 3.07 mm, respectively. CONCLUSION The GTs are a controversial anatomical landmark with wide variation in their morphological pattern. The most common pattern among the studied Saudi sample was of two superior GTs and a rough impression below them, and there were no significant differences between males and females.

关键词： Genial tubercles cone beam computed tomography Morphological analysis Mandible Anatomical landmark

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Liquefaction-Induced Ground Deformations Evaluation Based on cone Penetration Tests (CPT)

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World Journal of Engineering and Technology 2014年第4期2卷 249-259页

作者： Alketa Ndoj Neritan Shkodrani Veronika Hajdari Department of Civil Engineering Polytechnic University of Tirana Tirana Albania

The aim of this paper is to evaluate the liquefaction-induced ground deformations of sand-like soils based on cone Penetration Tests (CPT) at Semani site, Fieri prefecture in Albania. These tests are performed during the process of investigation of this area, in which a Liquid Natural Gas Terminal-Power Plant was supposed to be built. This paper presents the assessment of the liquefaction and of the liquefaction-induced ground deformations such as lateral spreading displacement and post-liquefaction reconsolidation settlement. The liquefaction-induced lateral spreading and post-liquefaction reconsolidation settlement are estimated based on CPT data according to the method in MNO-12 “soil liquefaction during earthquake”, presented by Idriss and Boulanger (2008). This evaluation is very important and should be taken into consideration for the design of engineering structures that will be constructed in this area. All the calculation’s results are shown in graphs. At the end, there are highlighted some conclusions regarding the liquefaction-induced ground deformations in this site.

关键词： Liquefaction cone Penetration Test Lateral Spreading Settlement Factor of Safety

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Seismic Activity and Seismic cone Tectonics on the West Coast of the United States

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Journal of Geoscience and Environment Protection 2019年第11期7卷 92-112页

作者： Lijun Chen Research Center of Earthquake Prevention and Disaster Reduction Engineering of Hunan Province (Retired) Changsha China

In the west coast of the United States, there are frequent strong earthquakes and volcanic activities in the crust, high accuracy of the earthquake catalogue, so it is the best choice to study prediction of strong earthquakes and volcanoes, and there are two different types of seismic cone tectonics, volcanic type and intracrustal strong seismicity type, so it becomes the epitome of global earthquake prediction research, rarer. In this paper, according to the data of ANSS earthquake catalogue in the United States, using the Seismo-Geothermic Theory and its methods, the images were processed such as the planar distribution images and the three-dimensional images of the general earthquakes, subcrustal earthquakes, intracrustal strong earthquakes and volcanic eruption and the sequence diagrams of subcrustal earthquakes in the study area, as well as theory explanation of their relations with the San Andreas Fault. According to this idea, the volcanic origin and precursory information of U01 mini seismic cone tectonic were firstly studied, then the causes of intracrustal strong seismicity of U02 mini seismic cone tectonic and their migration rules were studied. The precursory information of M7.1 earthquake on July 6, 2019, was analyzed and summarized in U02 mini seismic cone tectonic, and a basic method for handling similar events in the future was given. In this paper, it thinks strong earthquake and volcanic disaster are from deep mantle heat energy, rather than the result of the independence movement of surface structure. Therefore, it finds the most natural energy of causes of seismicity and volcanic activity and opens a new direction for the prediction research of earthquakes and volcanoes.

关键词： Seismo-Geothermic Theory (Seismo-Geothermics) Mini Seismic cone Tectonic Intracrustal Strong Earthquake Subcrustal Earthquake Volcano

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Diffraction of a Plane Acoustic Wave from a Finite Soft (Rigid) cone in Axial Irradiation

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Open Journal of Acoustics 2015年第4期5卷 193-206页

作者： Dozyslav B. Kuryliak Zinoviy T. Nazarchuk Victor O. Lysechko Department of Physical Basis for Diagnostic of Materials Karpenko Physico-Mechanical Institute of the NAS of Ukraine Lviv Ukraine

The problem of diffraction of a plane acoustic wave by a finite soft (rigid) cone is investigated. This one is formulated as a mixed boundary value problem for the three-dimensional Helmholtz equation with Dirichlet (Neumann) boundary condition on the cone surface. The diffracted field is sought as expansion of unknown velocity potential in series of eigenfunctions for each region of the existence of sound pressure. The solution of the problem then is reduced to the infinite set of linear algebraic equations (ISLAE) of the first kind by means of mode matching technique and orthogonality properties of the Legendre functions. The main part of asymptotic of ISLAE matrix element determined for large indexes identifies the convolution type operator amenable to explicit inversion. This analytical treatment allows one to transform the initial diffraction problem into the ISLAE of the second kind that can be readily solved by the reduction method with desired accuracy depending on a number of truncation. All these determine the analytical regularization method for solution of wave diffraction problems for conical scatterers. The boundary transition to soft (rigid) disc is considered. The directivity factors, scattering cross sections, and far-field diffraction patterns are investigated in both soft and rigid cases whereas the main attention in the near-field is focused on the rigid case. The numerically obtained results are compared with those known for the disc.

关键词： Acoustic Wave Finite cone Disc Far-Field Pattern Scattering Cross Section Near Field Analytical Regularization Procedure

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Effects of Irregular Respiratory Motion on the Positioning Accuracy of Moving Target with Free Breathing cone-Beam Computerized Tomography

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2018年第2期7卷 173-183页

作者： Xiang Li Tianfang Li Ellen Yorke Gig Mageras Xiaoli Tang Maria Chan Weijun Xiong Marsha Reyngold Richard Gewanter Abraham Wu John Cuaron Margie Hunt Department of Medical Physics Memorial Sloan Kettering Cancer Center New York NY USA Department of Radiation Oncology Memorial Sloan Kettering Cancer Center New York NY USA

For positioning a moving target, a maximum intensity projection (MIP) or average intensity projection (AIP) image derived from 4DCT is often used as the reference image which is matched to free breathing cone-beam CT (FBCBCT) before treatment. This method can be highly accurate if the respiratory motion of the patient is stable. However, a patient’s breathing pattern is often irregular. The purpose of this study is to investigate the effects of irregular respiration on positioning accuracy for a moving target aligned with FBCBCT. Nine patients’ respiratory motion curves were selected to drive a Quasar motion phantom with one embedded cubic and two spherical targets. A 4DCT of the phantom was acquired on a CT scanner (Philips Brilliance 16) equipped with a Varian RPM system. The phase binned 4DCT images and the corresponding MIP and AIP images were transferred into Eclipse for analysis. FBCBCTs of the phantom driven by the same respiratory curves were also acquired on a Varian TrueBeam and fused such that both CBCT and MIP/AIP images share the same target zero positions. The sphere and cube volumes and centroid differences (alignment error) determined by MIP, AIP and FBCBCT images were calculated, respectively. Compared to the volume determined by MIP, the volumes of the cube, large sphere, and small sphere in AIP and FBCBCT images were smaller. The alignment errors for the cube, large sphere and small sphere with center to center matches between MIP and FBCBCT were 2.5 ± 1.8 mm, 2.4 ± 2.1 mm, and 3.8 ± 2.8 mm, and the alignment errors between AIP and FBCBCT were 0.5 ± 1.1 mm, 0.3 ± 0.8 mm, and 1.8 ± 2.0 mm, respectively. AIP images appear to be superior reference images to MIP images. However, irregular respiratory pattern could compromise the positioning accuracy, especially for smaller targets.

关键词： cone Beam Computerized Tomography Respiratory Motion Effect

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Effect of Hartmann Number on Free Convective Flow of MHD Fluid in a Square Cavity with a Heated cone of Different Orientation

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American Journal of Computational Mathematics 2018年第4期8卷 314-325页

作者： Saika Mahjabin Md. Abdul Alim Department of Mathematics National University Gazipur Bangladesh Department of Mathematics Bangladesh University of Engineering & Technology Dhaka Bangladesh

This paper presents the effect of magnetic field, indicated by Hartmann number (Ha), on the free convective flow of Magneto-hydro-dynamic (MHD) fluid in a square cavity with a heated cone of different orientation. Although similar studies abound, the novelty of this work lies in the presence of the heated cone, whose orientation is varied at different angles. The mathematical model includes the system of governing mass, momentum and energy equations. The system is solved by finite element method. The calculations are performed for Prandtl number Pr = 0.71;the Rayleigh number Ra = 10, 1000, 100,000;and for Hartmann number Ha = 0, 20, 50, 100. The results are illustrated with streamlines, velocity profiles and isotherms. From the results, it is found that for the present configuration, magnetic field (Hartmann number) has no effect on the shape of the streamlines for low Rayleigh numbers. However, for high values of Ra, the effect of Ha becomes quite visible. Magnetic field affects the flow by retarding the fluid movement, and thus affects convective heat transfer. At low Ra, the fluid movement and heat transfer rate are already slowing, thus impressing a magnetic field does not produce much effect. At high Ra, fluid particles move at high velocity and change the stream lines, in absence of any magnetic force. Impressing magnetic field in this situation produced noticeable effect by slowing down the fluid movement and changing the streamlines back to low Ra situations. It is noted that a combination of low Ra with zero or low Ha produces similar effects with the combination of high Ra and high Ha. It can be concluded that with increasing Ha, heat transfer mode in MHD fluid gradually changes toward conduction from convection. It can be surmised that sufficiently large Ha can potentially stop the fluid movement altogether. In that case, heat transfer would be fully by conduction.

关键词： MHD Free Convection Hartmann Number Square Cavity Heated cone Finite Element Method

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Clinical Significance of Pathological and Anatomical Findings in cone Beam CT Scans of the Maxillary Sinus

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Open Journal of Stomatology 2014年第6期4卷 285-290页

作者： Eunice Kihara Mark Chindia Tom Ocholla Mohamed Parker Department of Diagnostics and Radiology University of Western Cape Cape Town South Africa Department of Oral & Maxillofacial Surgery Oral Pathology & Oral Medicine University of Nairobi Nairobi Kenya

Objective: To determine the range and prevalence of pathological conditions and demonstration of significant anatomical structures in the maxillary sinuses using the cone beam computerized tomographic (CBCT) scan. Methodology: Case series of 60 CBCT scans of the maxillae. Results: Forty (67%) of the scans were of female patients while the rest (20, 33%) were of males. Remarkably, the majority of the scans were requested for those patients who sought dental implant fabrication. Overall, 35 (58%) scans demonstrated pathological features while 8 (13%) demonstrated significant anatomical structures. Pathological features included mucosal thickening in 26 (43%), polypoid lesions in 9 (15%), total antral opacification in 1 (2%) and foreign body in 1 (2%). The commonest anatomic feature was dental root protrusion into the maxillary sinuses in 8 (13%). Conclusion: The CBCT imaging is an important tool for investigating the maxillary sinuses for pathology and the demonstration of the associated anatomic relations.

关键词： cone Beam CT Maxillary Antrum Oral Pathology

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Fixed Points and Common Fixed Points of Quasi-Contractive Mappings on Partially Ordered-cone Metric Spaces

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Applied Mathematics 2014年第21期5卷 3437-3444页

作者： Hailan Jin Yongjie Piao Department of Mathematics College of Science Yanbian University Yanji China

In this paper, we use the mappings with quasi-contractive conditions, defined on a partially ordered set with cone metric structure, to construct convergent sequences and prove that the limits of the constructed sequences are the unique (common) fixed point of the mappings, and give their corollaries. The obtained results improve and generalize the corresponding conclusions in references.

关键词： Common Fixed Point cone Metric Space Complete

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Knowledge and Practices of Dentists, Oral and Maxillofacial Surgeons of cone Beam Computed Tomography (CBCT) and the Dentascanner in a Low Income Country: Case of Togo

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Open Journal of Radiology 2017年第1期7卷 1-8页

作者： Mazamaesso Tchaou Haréfétéguéna Bissa Plaodesina Essobozou Pegbessou Abdoulatif Amadou Bidamin N’timon Mawuena Dansou Abdoul-Razakou Adam Lantam Sonhaye Lama-Kegdigoma Agoda-Koussema Komlan Adjenou Department of Radiology Sylvanus Olympio Teaching Hospital of Lomé Lomé Togo Department of Oral and Maxillofacial Surgery Sylvanus Olympio Teaching Hospital of Lomé Lomé Togo Department of ENT and Neck Surgery Sylvanus Olympio Teaching Hospital of Lomé Lomé Togo Department of Radiology Kara Teaching Hospital Lomé Togo

Background: In dental-maxillofacial imaging, 3D sectional imaging progressively replaces conventional 2D imaging in developed countries. They are based specially on Computed tomography (CT-Scan), with the Dentascan application and cone beam computed tomography (CBCT). In developing countries those technics are newly introduced. Aim: This study aimed at studying the knowledge and practices of dentist and oral and maxillofacial surgeons on sectional imaging such as Dentascan and cone Beam Computed Tomography (CBCT). Materials and Methods: We conducted an anonymous survey among dentists and oral maxillofacial surgeons in Togo over one month. Results: The response rate was 78.79% (27/33). They were mainly male sex (sex ratio of 2.25 men for one woman). They were aged between 27 and 71 years old with an average of 49.69 years old. The majority (61.54%) had a professional experience over 20 years. The majority of respondents (65.38%) believed their level of knowledge about dental x-Ray was poor. Half of them (50%) confirmed that they had never asked for a Dentascan, and 15.38% asked from time to time for it and only two (7.69%) asked often for this test. 96.15% confirm they have no knowledge of the Dentascan. Regarding the CBCT, 84.62% didn’t ask for it because this technique did not exist in Togo before. 69.20% of respondents confessed to be interested in continuing training on sectional imaging. Conclusion: This study shows that sectional imaging is very little used by oral and dental practitioners in Togo because of the ignorance of the new techniques and the absence of the CBCT. It is therefore necessary to promote the teaching of the new technique of sectional imaging in the training syllabus of oral and dental specialists and to initiate continuing medical training.

关键词： Knowledge Practice Dentascan cone Beam Computed Tomography (CBCT) Dentist Oral and Maxillofacial Surgeon Togo

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Relating cone Penetration and Rutting Resistance to Variations in Forest Soil Properties and Daily Moisture Fluctuations

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Open Journal of Soil Science 2017年第7期7卷 149-171页

作者： Marie-France Jones Paul A. Arp Forest Watershed Research Centre Faculty of Forestry and Environmental Management University of New Brunswick Fredericton Canada

Soil resistance to penetration and rutting depends on variations in soil texture, density and weather-affected changes in moisture content. It is therefore difficult to know when and where off-road traffic could lead to rutting-induced soil disturbances. To establish some of the empirical means needed to enable the “when” and “where” determinations, an effort was made to model the soil resistance to penetration over time for three contrasting forest locations in Fredericton, New Brunswick: a loam and a clay loam on ablation/ basal till, and a sandy loam on alluvium. Measurements were taken manually with a soil moisture probe and a cone penetrometer from spring to fall at weekly intervals. Soil moisture was measured at 7.5 cm soil depth, and modelled at 15, 30, 45 and 60 cm depth using the Forest Hydrology Model (ForHyM). cone penetration in the form of the cone index (CI) was determined at the same depths. These determinations were not only correlated with measured soil moisture but were also affected by soil density (or pore space), texture, and coarse fragment and organic matter content (R2 = 0.54;all locations and soil depths). The resulting regression-derived CI model was used to emulate how CI would generally change at each of the three locations based on daily weather records for rain, snow, and air temperature. This was done through location-initialized and calibrated hydrological and geospatial modelling. For practical interpretation purposes, the resulting CI projections were transformed into rut-depth estimates regarding multi-pass off-road all-terrain vehicle traffic.

关键词： Soil Resistance to Penetration cone Index Soil Moisture Texture Coarse Fragments Organic Matter Weather Records Hydrological Modelling Soil Trafficability Rutting Depth Recreational Vehicles

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