scholarly journals Anatomical Considerations and Study of the Fractal Dimension around the Posterior Superior Alveolar Artery

Symmetry ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1177
Author(s):  
Yolanda Guerrero-Sánchez ◽  
Francisco José Gómez García ◽  
Manuel Fernández-Martínez ◽  
Blanca Pallarés Martínez ◽  
Pia López-Jornet
Keyword(s):  
Fractal Dimension ◽  
Maxillary Sinus ◽  
Fractal Dimensions ◽  
Tissue Structure ◽  
Cone Beam ◽  
P Value ◽  
Linear Relationships ◽  
The Mean ◽  
Edentulous Patients ◽  
The One

The Posterior Superior Alveolar Artery (PSAA) provides vascular support to molars, gingiva, and maxillary sinus. A tear of the PSAA may cause profuse hemorrhages which may lead to complications at a surgical level. As such, it becomes crucial to anatomically analyse several features regarding the PSAA as well as the area surrounding it. In this paper, we are particularly interested in the study of the complexity of the periodontal tissue structure which appears close to the location of the PSAA. A total amount of 400 cone beam computed tomography (CBCT) scans (two per subject) were performed to explore the presence of the PSAA, the thickness of the Schneider’s membrane, and the existence of septa. Several parameters were evaluated including the location of the artery in the maxillary sinus, the distance from the PSAA to the alveolar ridge, the thickness of the membrane, the diameter of the cavities produced by the septa, and the fractal dimension of the trabecular tissue that surrounds the PSAA. They were found strong linear relationships between Distal and Central Measures (a Pearson’s R 2 = 0.9952 ), Mesial and Central Measures ( R 2 = 0.9950 ), and Distal and Mesial Measure ( R 2 = 0.997 ). We hypothesised that the loss of dental pieces would imply a distinct complexity of the trabecular tissue structure surrounding the PSAA. In this way, a p-value equal to 0.001 was provided by the Mann-Whitney test, which supports our hypothesis. Furthermore, the mean of the fractal dimensions of the group of edentulous patients (equal to 1.56 ) was found to be lower than the one of the group of non-edentulous patients (equal to 1.61 ) with small standard deviations in both cases. Our study suggests that accurate calculations of the fractal dimension combined with the use of CBCT do provide valuable information regarding the area that surrounds the PSAA.

Rapid rituximab infusion is safe and well tolerated in malignant and benign disease

2020 ◽  
pp. 107815522097845
Author(s):  
Sorana G Ursu ◽  
Derek L Rinchuse ◽  
John Lister
Keyword(s):  
Medical Records ◽  
Malignant Disease ◽  
Benign Disease ◽  
P Value ◽  
Infusion Time ◽  
Benign Diseases ◽  
Secondary Objective ◽  
The Mean ◽  
The One ◽  
Related Reaction

Introduction Although the safety and feasibility of rapid rituximab administration has been demonstrated for B-cell malignancies, there is scant data in the literature to support its use in patients with benign diseases. Objective To identify the incidence of infusion-related reaction with rapid rituximab administration in malignant and benign disease. Secondary objective was to determine the infusion time saved between standard administration and rapid rituximab administration. Methods A retrospective cohort study was conducted by reviewing electronic medical records from December 2018 to April 2020. Adult patients who received at least one dose of rapid rituximab were included. Results A total of 63 patents were included. The incidence of an infusion-related reaction with rapid rituximab was 1.6%. The one patient who reacted had a diagnosis of neuromyelitis optica. The mean infusion time saved was 2.9 hours (95% CI: 2.7-3.1; P-value <0.001). Conclusion The use of the rapid rituximab administration is safe and well tolerated in both benign and malignant disease.

scholarly journals Fractal properties and simulation of micro-seismicity for seismic hazard analysis: a comparison of North Anatolian and San Andreas Fault Zones

2012 ◽  
Vol 2 (1) ◽  
pp. 1 ◽  
Author(s):  
Naside Ozer ◽  
Savas Ceylan
Keyword(s):  
Fractal Dimension ◽  
Seismic Hazard ◽  
Fault Zone ◽  
San Andreas Fault ◽  
Fractal Dimensions ◽  
Fault Zones ◽  
Group Method ◽  
Western Anatolia ◽  
P Value ◽  
San Andreas

We analyzed statistical properties of earthquakes in western Anatolia as well as the North Anatolian Fault Zone (NAFZ) in terms of spatio-temporal variations of fractal dimensions, p- and b-values. During statistically homogeneous periods characterized by closer fractal dimension values, we propose that occurrence of relatively larger shocks (M &gt;= 5.0) is unlikely. Decreases in seismic activity in such intervals result in spatial b-value distributions that are primarily stable. Fractal dimensions decrease with time in proportion to increasing seismicity. Conversely, no spatiotemporal patterns were observed for p-value changes. In order to evaluate failure probabilities and simulate earthquake occurrence in the western NAFZ, we applied a modified version of the renormalization group method. Assuming an increase in small earthquakes is indicative of larger shocks, we apply the mentioned model to micro-seismic (M&lt;= 3.0) activity, and test our results using San Andreas Fault Zone (SAFZ) data. We propose that fractal dimension is a direct indicator of material heterogeneity and strength. Results from a model suggest simulated and observed earthquake occurrences are coherent, and may be used for seismic hazard estimation on creeping strike-slip fault zones.

scholarly journals Assessment of Location of Mental Foramen in Mandible Using Cone Beam Computerized Tomography

2020 ◽  
Vol 10 (4) ◽  
pp. 291-295
Author(s):  
Shoaib Rahim ◽  
Maria Shakoor ◽  
Ali Qureshi
Keyword(s):  
Computerized Tomography ◽  
Care Center ◽  
Tertiary Care ◽  
Mental Foramen ◽  
Cone Beam ◽  
P Value ◽  
Mandibular Symphysis ◽  
Cone Beam Computerized Tomography ◽  
The Mean ◽  
Inferior Border

Objective: To determine the mean distance of mental foramen from the base of the mandible and mandibular symphysis in patients reporting to tertiary care center using Cone Beam Computerized Tomography (CBCT). Study design and setting: Cross-Sectional Study was carried out in the Prosthodontics Department, Foundation University College of Dentistry, Islamabad from March 2019 to August 2019. Methodology: Total 100 patients between the age of 20-45 years were participated. CBCT investigation was carried out and measurements of mental foramen from the base of the mandible and mandibular symphysis in patients were recorded with the help of measuring tools in the software and noted down on the performa. SPSS version 20 was used analyze the data. P value less than 0.05 was considered as statistically significant. . Frequency and percentages were calculated for variable gender (qualitative). For quantitative variables like age, distance mental foramen from the mandibular Symphysis and inferior border of mandible, mean + SD were calculated. Independent samples t-test was used to compare quantitative variables like distance MF from the mandibular symphysis/midline and inferior border of mandible. P values < 0.05 was considered as statistically significant. Results: The Mean+SD distance of anterior border of mental foramen from symphysis on left and right side were 24.12+2.835 and 24.88+2.637 and from the lower border of mandible were 11.97+1.359 and 12.00+1.764 respectively. Conclusion: The mean vertical and horizontal distances calculated in this study can provide a useful guide to dentist to safely place dental implants within the inter-foraminal region in our population

scholarly journals The linkage between box-counting and geomorphic fractal dimensions in the fractal structure of river networks: the junction angle

2020 ◽  
Vol 51 (6) ◽  
pp. 1397-1408
Author(s):  
Xianmeng Meng ◽  
Pengju Zhang ◽  
Jing Li ◽  
Chuanming Ma ◽  
Dengfeng Liu
Keyword(s):  
Fractal Dimension ◽  
Fractal Structure ◽  
Fractal Dimensions ◽  
River Networks ◽  
Stream Length ◽  
Box Counting ◽  
Linear Relationships ◽  
Box Counting Dimension ◽  
Junction Angle

Abstract In the past, a great deal of research has been conducted to determine the fractal properties of river networks, and there are many kinds of methods calculating their fractal dimensions. In this paper, we compare two most common methods: one is geomorphic fractal dimension obtained from the bifurcation ratio and the stream length ratio, and the other is box-counting method. Firstly, synthetic fractal trees are used to explain the role of the junction angle on the relation between two kinds of fractal dimensions. The obtained relationship curves indicate that box-counting dimension is decreasing with the increase of the junction angle when geomorphic fractal dimension keeps constant. This relationship presents continuous and smooth convex curves with junction angle from 60° to 120° and concave curves from 30° to 45°. Then 70 river networks in China are investigated in terms of their two kinds of fractal dimensions. The results confirm the fractal structure of river networks. Geomorphic fractal dimensions of river networks are larger than box-counting dimensions and there is no obvious relationship between these two kinds of fractal dimensions. Relatively good non-linear relationships between geomorphic fractal dimensions and box-counting dimensions are obtained by considering the role of the junction angle.

scholarly journals Association between Cone-Beam Computed Tomography and Histological and Immunohistochemical Features in Periapical Lesions Correlated with Thickened Maxillary Sinus Mucosa

Medicina ◽  
2021 ◽  
Vol 57 (8) ◽  
pp. 840
Author(s):  
Alexandra Dumitrescu ◽  
Maria-Alexandra Martu ◽  
Alexandru Nemtoi ◽  
Ana Sirghe ◽  
Liliana Chelaru ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Maxillary Sinus ◽  
B Lymphocytes ◽  
Cone Beam Computed Tomography ◽  
Maxillary Sinusitis ◽  
Cone Beam ◽  
Periapical Lesions ◽  
Significant Difference ◽  
The Mean ◽  
Sinus Mucosa

Background and Objectives: Odontogenic sinusitis is a frequently underestimated pathology with fewer symptoms in patients with periapical lesions, periodontal disease, or iatrogenic foreign bodies in the maxillary sinus. The aim of our study was to determine the correlation between maxillary sinusitis and periapical lesions using cone-beam computed tomography (CBCT) imaging and histological and immunohistochemical investigations. Materials and Methods: A total of 1450 initial patients diagnosed with maxillary sinusitis in the Ear-Nose-Throat (ENT) Department, University of Medicine and Pharmacy “Grigore T. Popa” Iasi, Romania, were treated with anti-inflammatory drugs. Of these, 629 still had unresolved symptomatology and were later referred to the Dental Medicine departments for further investigations. Only 50 subjects with periapical lesions in the premolar/molar maxillary area were included in the present study. All the periapical lesions were observed on CBCT and classified using the Periapical Status Index (PSI) and the mean maxillary sinus mucosa thicknesses (MSMT). The enrolled patients underwent surgical procedures with the excision of periapical lesions. The excised samples were submitted to the histological and immunohistochemical investigations. Results: The 50 patients presented periapical lesions of their maxillary teeth in 328 dental units. There was a higher prevalence of periapical lesions in men than in women (chi-square test). We observed a significant difference between the mean MSMT of individuals with periapical lesions compared to those without (p < 0.01). Mean MSMT was 1.23 mm for teeth without periapical lesions and 3.95 mm for teeth with periapical lesions. The histopathological study identified 50% cases with periapical granulomas, 10% cases with periapical granulomas with cystic potential, and 40% cases as periapical cysts. Immunohistochemical stainings showed that CD4+ helper and CD8+ cytotoxic T lymphocytes, along with CD20+ B lymphocytes and CD68+ macrophages, were diffusely distributed in all periapical cysts and in some periapical granulomas, but CD79α+ plasma cells characterized especially periapical granulomas. Conclusions: The current study observed a significant correlation between CBCT maxillary mucosa thickness and type of periapical lesion. Chronic inflammatory lympho-histiocytic infiltrate predominates in periapical lesions, supporting the idea that lesion progression is determined by a humoral-type (CD20+ and CD79α+ B lymphocytes) but also by a cellular-type (CD4+ and CD8+ T lymphocyte population) immune mechanism.

scholarly journals Application of the Fractal Dimension Calculation Technique to Determine the Shape of Selected Monchepluton Intrusion Crystals (NE Fennoscandia)

Minerals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1140
Author(s):  
Miłosz Huber ◽  
Klaudia Stępniewska
Keyword(s):  
Fractal Dimension ◽  
Fractal Dimensions ◽  
Mean Value ◽  
Computational Technique ◽  
Calculation Technique ◽  
Euhedral Crystal ◽  
The Mean ◽  
Crystal Boundaries

Thirty-eight samples of minerals from Paleoproterozoic Layered PGE Intrusion Monchepluton, located in NE Fennoscandia, were tested. An automated computational technique was used which involved counting the sides superimposed on vectorized graphics using separated crystal boundaries. The results were obtained for olivine, orthopyroxene, clinopyroxene, and plagioclase. On this basis, an interpretation of the mineral box fractal dimension was made, along with an interpretation of its nature in the rock in which it was found. The performed calculations were applied to the sampling positions, and maps of changes in fractal dimensions were prepared. The nature of the minerals studied was correlated with the type of rocks present in Monchepluton. Then, the fractal dimensions were scaled to a percentage scale determining the mean value for the euhedral crystal as 100%, and a map was obtained representing the advancement of secondary processes after summing these data for all four investigated minerals. This method was analyzed and its advantages and limitations shown.

A Microcontact Model Developed for Asperity Heights With a Variable Profile Fractal Dimension, a Surface Fractal Dimension, Topothesy, and Non-Gaussian Distribution

2008 ◽  
Author(s):  
Jen Luen Liou ◽  
Jen Fin Lin
Keyword(s):  
Fractal Dimension ◽  
Cross Sections ◽  
Fractal Dimensions ◽  
Surface Fractal Dimension ◽  
Surface Fractal ◽  
Deformation Regime ◽  
Circular Contour ◽  
The Mean ◽  
Non Gaussian ◽  
The Relationship

The cross sections formed by the contact asperities of two rough surfaces at an interference are island-shaped, rather than having the commonly assumed circular contour. These island-shaped contact surface contours show fractal behavior with a profile fractal dimension Ds. The surface fractal dimension for the asperity heights is defined as D and the topothesy is defined as G. In the study of Mandelbrot, the relationship between D and Ds was given as D = Ds+1 if these two fractal dimensions are obtained before contact deformation. In the present study, D, G, and Ds are considered to be varying with the mean separation (or the interference at the rough surface) between two contact surfaces. The D-Ds relationships for the contacts at the elastic, elastoplastic, and fully plastic deformations are derived and the inceptions of the elastoplastic deformation regime and the fully plastic deformation regime are redefined using the equality of two expressions established in two different ways for the number of contact spots (N).

scholarly journals A Study on Measurements of Different Dimensions of Maxillary Sinus by Computed Tomography in Adult Nepalese Population

2018 ◽  
Vol 8 (2) ◽  
pp. 8-12
Author(s):  
Umesh Prasad Khanal ◽  
Anupama Adhikari ◽  
Mukunda Prasad Humagain
Keyword(s):  
Computed Tomography ◽  
Maxillary Sinus ◽  
Anterior Wall ◽  
Mean Value ◽  
Forensic Sciences ◽  
P Value ◽  
Male Population ◽  
Different Dimensions ◽  
Left And Right ◽  
The Mean

Introduction: Measurement of different dimensions of maxillary sinus and anterior wallthickness of maxillary sinus by Computed Tomography in normal Nepalese populationMethods: Dimensions of 90 patients were measured in CT PNS using Syngovia Software. AP diameter, width and anterior wall thickness were measured in axial images and height was measured in coronal images.Results: The mean volume of maxillary sinuses in study of male population on left and right side were 17.09 cm3±3.89, 17.19 cm3 ±4 respectively whereas in female were 15.64 cm3±3.5 and 15.21cm3±3.2 respectively as shown in Table 1. This shows the volume of male was significantly larger than female with P- Value = 0.012 (<0.05). Similarly, the thickness of Anterior Wall (AW) of maxillary sinus was also measured in this study and the mean value of left and right side in male were 0.16cm± 0.04 and 0.15cm± 0.03 respectively and in female were 0.12cm± 0.04 and 0.14cm± 0.02 respectively.Conclusion: This study showed that CT is a reliable method for the measurement of different dimensions of the maxillary sinus. The result showed greater mean value of volume in male than female with significant differences. So this study concluded that the measurement of volume of maxillary sinus can help in the identification of gender which can be very useful for forensic sciences.

FRACTAL ANALYSIS OF DENDRITIC ARBORISATION PATTERNS OF STALKED AND ISLET NEURONS IN SUBSTANTIA GELATINOSA OF DIFFERENT SPECIES

Fractals ◽  
2007 ◽  
Vol 15 (01) ◽  
pp. 1-7 ◽  
Author(s):  
NEBOJŠA T. MILOŠEVIĆ ◽  
DUŠAN RISTANOVIĆ ◽  
JOVAN B. STANKOVIĆ ◽  
RADMILA GUDOVIĆ
Keyword(s):  
Fractal Dimension ◽  
Fractal Analysis ◽  
Islet Cells ◽  
Fractal Dimensions ◽  
Substantia Gelatinosa ◽  
Neuronal Populations ◽  
Box Counting ◽  
Morphological Descriptor ◽  
The Mean ◽  
Box Counting Method

Through analysis of the morphology of dendritic arborisation of neurons from the substantia gelatinosa of dorsal horns from four different species, we have established that two types of cells (stalked and islet) are always present. The aim of the study was to perform the intra- and/or inter-species comparison of these two neuronal populations by fractal analysis, as well as to clarify the importance of the fractal dimension as an objective and usable morphological parameter. Fractal analysis was carried out adopting the box-counting method. We have shown that the mean fractal dimensions for the stalked cells are significantly different between species. The same is true for the mean fractal dimensions of the islet cells. Still, no significant differences were found for the fractal dimensions of the stalked and islet cells within a particular species. The human species has shown as the only exception where fractal dimensions of these two types of cells differ significantly. This study shows once more that the fractal dimension is a useful and sensitive morphological descriptor of neuronal structures and differences between them.

The Comparison of Fractal Dimensions of Cracks on Reinforced Concrete Beam

2011 ◽  
Vol 291-294 ◽  
pp. 1126-1130 ◽  
Author(s):  
Hong Quan Sun ◽  
Jun Ding
Keyword(s):  
Fractal Dimension ◽  
Reinforced Concrete ◽  
Concrete Beam ◽  
Research Result ◽  
Fractal Dimensions ◽  
Reinforce Concrete ◽  
Reinforced Concrete Beam ◽  
Linear Relationships ◽  
Practical Engineering ◽  
Box Counting Method

In the paper, fractal geometry is used to study the crack evolving process of reinforce concrete beams. The fractal dimensions on surface of the reinforced concrete beam and the mechanical properties of the beam have the linear relationships perfectly. In order to compare the accuracy of the fractal dimensions, box counting method and the digital image box method in practical engineering are used to calculate the fractal dimension separately. The advantages and the disadvantages of these methods are analyzed. And the calculating conditions of these two methods are obtained. The research result gives a better way for determining the fractal dimension of the cracks on the reinforced concrete beam.

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