scholarly journals Choice of Screws for Fixation of Mandibular Condyle Fractures Guided by Anthropometric Data

2021 ◽  
Vol 11 (8) ◽  
pp. 3371
Author(s):  
Bartosz Bielecki-Kowalski ◽  
Marcin Kozakiewicz
Keyword(s):  
Treatment Time ◽  
Mandibular Condyle ◽  
3D Models ◽  
Condylar Process ◽  
Sigmoid Notch ◽  
Cohort Group ◽  
Plate Length ◽  
Screw Length ◽  
The Stability ◽  
Made In

Open reduction and internal fixation (ORIF) is becoming increasingly common in treatment of the condylar process, including mandible head fractures. This approach significantly improves the results in terms of anatomical reduction of bone fragments, and shortens the treatment time, allowing for early functional recovery. The success of ORIF is largely determined by the stability of the osteosynthesis. The stabilization effect depends on the screw type and length of the plate used, in addition to the diameter and length of the screws used. The aim of this study was to determine the largest possible screw length that can be used in ORIF of the mandibular condyle considering the variable bone thickness. A total of 500 condyles were examined using computer tomography (CT)-based 3D models in Caucasians. For all models, three measurements were made in the frontal projection in places typical for the stabilization of osteosynthesis plates in the fractures of the condylar process: the base, the top, and the sigmoid notch. In addition, one measurement of the mandible head was made in the place of the greatest width. The results showed that 8 mm screws should be used in the region of the condylar base as the longest anatomically justified screw, whereas in the area of a sigmoid notch only 1.5–2 mm screws should be used. Measurements in the area of the neck top revealed statistically significant differences in the measurements between the sex of patients, with average differences below 1 mm (p < 0.05). In this area, the maximal length of the screw was found to be 10 mm. In mandibular head fractures, the use of long screws is extremely important due to the desired effect of fragment compression. Statistically significant differences were found in the measurement results between women and men. The maximal screw length for bicortical fixation was found to be 22 mm in men and 20 mm in women. In post-traumatic patients, the ability to obtain a clear measurement is often limited by a deformed anatomy. Taking into account the fact that the fracture stability is influenced by both the plate length and the length of the fixation screws, an assessment of the standard measurement values in a cohort group will improve the quality of the surgical fixations of the fractures.

Injuries to the Coronoid Process of the Ulna with Involvement of the Lesser Sigmoid Notch

2020 ◽  
Author(s):  
Valentin Rausch ◽  
Sina Neugebauer ◽  
Tim Leschinger ◽  
Lars Müller ◽  
Kilian Wegmann ◽  
...  
Keyword(s):  
Fragment Size ◽  
Coronoid Process ◽  
Annular Ligament ◽  
Concomitant Injuries ◽  
Proximal Ulna ◽  
Sigmoid Notch ◽  
Coronoid Fractures ◽  
The Mean ◽  
The Stability ◽  
Arthritic Changes

Abstract Introduction This study aimed to describe the involvement of the lesser sigmoid notch in fractures to the coronoid process. We hypothesized that injuries to the lateral aspect of the coronoid process regularly involve the annular ligament insertion at the anterior lesser sigmoid notch. Material and Methods Patients treated for a coronoid process fracture at our institution between 06/2011 and 07/2018 were included. We excluded patients < 18 years, patients with arthritic changes or previous operative treatment to the elbow, and patients with concomitant injuries to the proximal ulna. In patients with involvement of the lesser sigmoid notch, the coronoid height and fragment size (anteroposterior, mediolateral, and craniocaudal) were measured. Results Seventy-two patients (mean age: 47 years ± 17.6) could be included in the study. Twenty-one patients (29.2%) had a fracture involving the lateral sigmoid notch. The mean anteroposterior fragment length was 7 ± 1.6 mm. The fragment affected a mean of 43 ± 10.8% of the coronoid height. The mean mediolateral size of the fragment was 10 ± 5.0 mm, and the mean cranio-caudal size was 7 ± 2.7 mm. Conclusion Coronoid fractures regularly include the lesser sigmoid notch. These injuries possibly affect the anterior annular ligament insertion which is important for the stability of the proximal radioulnar joint and varus stability of the elbow.

Observations on some basal failures in sheeted excavations

1970 ◽  
Vol 7 (2) ◽  
pp. 136-144 ◽  
Author(s):  
V. Milligan ◽  
K. Y. Lo
Keyword(s):  
Shear Strength ◽  
Ground Water ◽  
Groundwater Level ◽  
Soil Conditions ◽  
Remedial Measures ◽  
Factors Influencing ◽  
Water Head ◽  
The Stability ◽  
Made In

In excavations below groundwater level, instability of the base may result from the inflow of water into the excavation. The most important factors influencing the stability are the ground water and detailed soil conditions at the site.Construction problems encountered in excavations in clay strata, underlain by pervious water bearing layers, are described. The remedial measures adopted in each case are also discussed. From a study of the observations made in the case records, it is suggested that excavation in intact clays may be carried out to depths exceeding that limited by the ratio of t/h = 0.5, where t is the distance from the bottom of the excavation to the top of the water bearing stratum, and h is the water head at the top of the water bearing stratum, provided that the clay is not disturbed during construction so that the shear strength of the clay is preserved.

scholarly journals Kerukunan Umat Beragama: Relevansi Pasal 25 Piagam Madinah dan Pasal 29 UUD 1945

2019 ◽  
Vol 21 (2) ◽  
pp. 162
Author(s):  
Nurul Fajriah
Keyword(s):  
20Th Century ◽  
Religious Diversity ◽  
The State ◽  
Religious Communities ◽  
Modern Times ◽  
Indonesian Government ◽  
Important Concern ◽  
Similarities And Differences ◽  
The Stability ◽  
Made In

This article is a study of literature describing religious harmony: the relevance of Article 25 of the Medina Charter and Article 29 of the 1945 Constitution. The Medina Charter was made in the 7th century (classical century) and Article 29 of the 1945 Constitution was born in modern times, around the 20th century. Both have relevancy which states that every citizen is free to adhere to their respective religions. The plurality of society in Indonesia has similarities and differences from the plurality of society in Medina around 622 AD. The stability and harmony of religious communities in the Medina at that time was regulated in the Medina charter which is the constitution of the Medina state. Harmony among religious communities in Indonesia is also an important concern of the Indonesian government as stipulated in Article 29 of the 1945 Constitution. Freedom of religion is guaranteed by the state because the state believes that religious diversity is not a disintegrating factor for the Indonesian people.Abstrak: Artikel ini adalah kajian literatur yang mendeskripsikan kerukunan umat beragama: relevansi pasal 25 Piagam Madinah dan Pasal 29 UUD 1945. Piagam Madinah dibuat pada abad VII (abad klasik) dan pasal 29 UUD 1945 baru lahir pada zaman modern, sekitar abad XX. Keduanya memiliki relevansi yang menyatakan bahwa setiap warga negara bebas menganut agamanya masing-masing. Kemajemukan masyarakat di Indonesia mempunyai sisi-sisi persamaan dan perbedaan dengan kemajemukan masyarakat di Madinah sekitar tahun 622 M. Keberlangsungan dan keharmonisan umat beragama di negara Madinah pada waktu itu diatur dalam piagam Madinah yang merupakan konstitusi negara Madinah. Kerukunan antar umat beragama di Indonesia juga menjadi perhatian penting pemerintah dengan adanya kebijakan Negara Republik Indonesia dari segi agama yang tertuang dalam pasal 29 UUD 1945. Kebebasan beragama ini dijamin oleh negara karena keyakinan bahwa keberagaman agama tidak akan menjadi disentegrating factor bagi bangsa Indonesia

Effect of Heat-Treatment Time on Microstructure and Mechanical Properties of Mg-5Gd-2Y-2Zn-0.5Zr Alloy

2012 ◽  
Vol 482-484 ◽  
pp. 1384-1389 ◽  
Author(s):  
Ling Gang Meng ◽  
Can Feng Fang ◽  
Peng Peng ◽  
Nai Pu Li ◽  
Qiong Zhu ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Grain Boundary ◽  
Treatment Time ◽  
Time Range ◽  
Lpso Phase ◽  
High Temperature Heat Treatment ◽  
Lpso Structure ◽  
The Matrix ◽  
New Type ◽  
The Stability

Microstructure evolution of Mg-5Gd-2Y-2Zn-0.5Zr alloy during high temperature heat-treatment at 500°C in the time range 10-70h was investigated. The results show that after adding the element Y, the as-cast Mg-5Gd-2Y-2Zn-0.5Zr alloy forms the Mg12Zn(Y,Gd) phase with 18R-LPSO structure at the grain boundary. During heat-treatment at 500°C, the stability of 18R-LPSO structure is weakened by Gd atoms, parts of LPSO phases dissolve gradually into the matrix with time prolonged and a new type Mg(Y,Gd)Zn phase come into being. LPSO phase in the grain boundary can ensure the ultimate tensile strength and elongation of the alloy, and effect of dissevering on the LPSO phase by Mg(Gd,Y)Zn phase results the decrease of UTS and elongation.

EFFECT OF ADDED TIP MASS ON THE NONLINEAR FLAPWISE AND CHORDWISE VIBRATION OF CANTILEVER COMPOSITE BEAM UNDER BASE EXCITATION

2012 ◽  
Vol 12 (02) ◽  
pp. 285-310 ◽  
Author(s):  
M. EFTEKHARI ◽  
M. MAHZOON ◽  
S. ZIAEI-RAD
Keyword(s):  
Cantilever Beam ◽  
Multiple Scales ◽  
Equilibrium Points ◽  
Laminated Composite ◽  
Base Excitation ◽  
System A ◽  
Autoparametric Resonance ◽  
The Stability ◽  
Tip Mass ◽  
Made In

In this paper, a comparative study is performed for a symmetrically laminated composite cantilever beam with and without a tip mass under harmonic base excitation. The base is subjected to both flapwise and chordwise excitations tuned to the primary resonances of the two directions and conditions of 2:1 autoparametric resonance. In the literature, the governing nonlinear equations of the same problem without tip mass have been derived using the extended Hamilton's principle. Extension is made in this study to include the effect of a tip mass on the response of the beam. The natural frequencies are obtained numerically using the diversity guided evolutionary algorithm (DGEA). Next, the multiple scales method is applied to determine the nonlinear response and stability of the system. A set of four first-order differential equations describing the modulation of the amplitudes and phases of interacting modes are derived for the perturbation analysis. For verification, the above equations are reduced to the special case of the cantilever beam without tip mass for comparison with existing results. Finally, the effect of the tip mass on the stability of the fixed points and on the amplitude of oscillation about the equilibrium points in both the frequency and force modulation responses is examined.

The Stability of γ ’-Co3(Al,W) Phase in Co-Al-W Ternary System

2010 ◽  
Vol 654-656 ◽  
pp. 448-451 ◽  
Author(s):  
Yuki Tsukamoto ◽  
Satoru Kobayashi ◽  
Takayuki Takasugi
Keyword(s):  
Heat Treatment ◽  
Ternary System ◽  
Microstructural Evolution ◽  
Treatment Time ◽  
Bulk Alloy ◽  
Epma Analysis ◽  
Heat Treated ◽  
Cold Rolled ◽  
The Stability ◽  
Couple Method

The thermodynamic stability ’- Co3(Al,W) phase (L12) in the Co-Al-W ternary system at 900 °C was investigated through microstructure and EPMA analysis on a heat-treated bulk alloy. To promote microstructural evolution, the bulk alloy was cold rolled before heat treatment. By heating at 900 °C, the ’ phase was formed discontinuously in contact with the -Co (A1) phase. With increasing heat treatment time, however, the fraction of ’ phase decreased while that of , CoAl (B2) and Co3W (D019) phases increased. These results are consistent with our previous work with a diffusion-couple method, indicating that the ’ phase is metastable, and the three phases of, CoAl and Co3W are thermodynamically stable at 900 °C.

Occurrence and Prevention of Changes in the Chemical Structure of Natural Rubber Tire Tread Vulcanizates during Service

1970 ◽  
Vol 43 (5) ◽  
pp. 1215-1224 ◽  
Author(s):  
J. I. Cunneen ◽  
R. M. Russell
Keyword(s):  
Chemical Structure ◽  
Main Chain ◽  
Heavy Duty ◽  
Structural Alterations ◽  
The Road ◽  
Rubber Tire ◽  
Before And After ◽  
On The Road ◽  
The Stability ◽  
Made In

Abstract The chemical structure of the tread vulcanizate of heavy-duty tires has been investigated before and after service on the road, and after testing under conditions designed to induce tread-lift. Significant changes occurred. These included a marked reduction in the concentration of polysulfide crosslinks, and an increase in the amount of monosulfide crosslinks and main chain modification. Experiments with vulcanizates made in the laboratory indicated that the structural alterations in the tires were due to thermal anaerobic reactions caused by heat build-up, and that they resulted in a deterioration in some of the physical properties of the tread vulcanizate. The rate of desulfuration of ‘model’ polysulfides has been found to depend critically upon the nature of the vulcanization recipe. These novel findings point the way to improving the stability of vulcanizates used in the treads of tires and, consequently, tire performance.

scholarly journals Design of Augmented Nonlinear PD Controller of Delta/Par4-Like Robot

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Amjad J. Humaidi ◽  
Ahmed Ibraheem Abdulkareem
Keyword(s):  
Trajectory Tracking ◽  
Lyapunov Method ◽  
Dynamic Performance ◽  
Parallel Robot ◽  
Pd Controller ◽  
Comparison Study ◽  
Tracking Accuracy ◽  
Control Schemes ◽  
The Stability ◽  
Made In

This work presents the design of two control schemes for a Delta/Par4-like parallel robot: augmented PD (APD) controller and augmented nonlinear PD (ANPD) controller. The stability of parallel robot based on nonlinear PD controller has been analyzed and proved based on Lyapunov method. A comparison study between APD and ANPD controllers has been made in terms of performance and accuracy improvement of trajectory tracking. Also, another comparison study has been presented between augmented nonlinear PD (ANPD) controller and nonaugmented nonlinear PD (NANPD) controller in order to show the enhancement of introducing the augmented structure on dynamic performance and trajectory tracking accuracy. The effectiveness of augmented PD controllers (APD and ANPD) and nonaugmented nonlinear PD (NANPD) controller for the considered parallel robot are verified via simulation within the MATLAB environment.

scholarly journals Uji Stabilitas Sediaan Mikroemulsi Menggunakan Hidrolisat Pati (DE 35–40) Sebagai Stabilizer

2006 ◽  
Vol 3 (1) ◽  
pp. 8-21
Author(s):  
Mahdi Jufri ◽  
◽  
Effionora Anwar ◽  
Putri Margaining Utami
Keyword(s):  
Drug Delivery ◽  
Dosage Form ◽  
Tween 80 ◽  
Microemulsion System ◽  
Hydrophobic Drug ◽  
Dextrose Equivalent ◽  
Oil In Water ◽  
External Phase ◽  
The Stability ◽  
Made In

Various solubilization techniques have been developed to enhance the bioavailability of hydrophobic drugs. One of the solubilization techniques is preparation of microemulsion. Microemulsion is a potential carrier in drug delivery system because it has many advantageous characteristics. In this research, hydrophobic drug was made in a dosage form of oil in water (O/W) microemulsion using ketoprofen as a model and investigated the influence of adding starch hydrolisates with dextrose equivalent (DE) 35-40 in variety concentrations (0,0%; 1,5%; 2,0%; 2,5%) to the stability of this microemulsion system. This microemulsion consisted of isopropyl miritate as oil phase, tween 80 and lechitin as surfactants, ethanol as cosurfactant, propylene glycol as cosolvent, starch hydrolisates DE 35–40 as stabilizer, and water as external phase. The evaluation was stability test both phisically and chemically. The result showed that the stability of microemulsion system increased significantly by adding starch hydrolisates DE 35-40 at 2,5%.

Stability Issues with Classifier Using Lukasiewicz Similarity and Modified Schweizer & Sklar Equations

2005 ◽  
Vol 9 (5) ◽  
pp. 514-525 ◽  
Author(s):  
Pasi Luukka ◽  
◽  
Jouni Sampo
Keyword(s):  
The Other ◽  
Classification Task ◽  
Classification Problems ◽  
Generalized Mean ◽  
The Stability ◽  
Stability Issues ◽  
Made In

In this article we have tested the stability of a classifier based on Lukasiewicz similarity in the generalized Lukasiewicz structure. We have also tested Schweizer & Sklar's implications with an extension to generalized mean to classification task. We will show that classification results are not so sensitive to p values with Schweizer & Sklar's measures, which indicates a generalized form of equations. In this article we have also tested the stability of these measures. Two different tests for stability were made: In one test the stability was checked with respect to weight parameters and the other test was carried out for idealvectors. The tests were done with five different classification problems.

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