scholarly journals Association between preferred chewing side and dynamic occlusal parameters

2019 ◽  
Vol 47 (5) ◽  
pp. 1908-1915 ◽  
Author(s):  
Satheesh B. Haralur ◽  
Muhammad Irfan Majeed ◽  
Saurabh Chaturvedi ◽  
Nasser M. Alqahtani ◽  
Mohammed Alfarsi
Keyword(s):  
Contact Area ◽  
Correlation Coefficients ◽  
Initial Contact ◽  
Strong Positive Correlation ◽  
Contact Center ◽  
Time Data ◽  
Tooth Contact ◽  
Masticatory Efficiency ◽  
Chi Squared ◽  
Occlusal Interferences

Objectives Evaluation of dynamic occlusal parameters can help dentists to understand the association of occlusion with the preferred chewing side (PCS) and enable optimal restoration of masticatory efficiency. This study evaluated the association between PCS and dynamic occlusal parameters. Methods One hundred participants (50 each, right and left PCS) were included in this study. PCS was determined by the visual spot-checking method, and occlusal analysis was conducted by T Scan. Occlusal parameters evaluated included initial contact, center of force, tooth contact area, occlusal interferences, and occlusal time. Data were assessed by chi-squared test and eta correlation coefficient. Results Initial contact towards the PCS was observed in 68% and 70% of right and left unilateral chewers, respectively. Likewise, center of force towards the PCS was present in 72% and 66% of right and left unilateral chewers, respectively. A larger area of tooth contact was predominant towards the PCS in 70% and 72% of right and left unilateral chewers, respectively. Chi-squared analysis showed a strong positive correlation between PCS and occlusal parameters at maximum intercuspation. Eta correlation coefficients between PCS and occlusal interferences, as well as centric and eccentric occlusion, revealed negligible associations. Conclusion Dynamic occlusal parameters may be associated with PCS.

Relationship amongst ResearchGate altmetric indicators and Scopus bibliometric indicators

2015 ◽  
Vol 116 (9/10) ◽  
pp. 564-577 ◽  
Author(s):  
RISHABH SHRIVASTAVA ◽  
Preeti Mahajan
Keyword(s):  
Sample Size ◽  
Correlation Coefficients ◽  
Strong Positive Correlation ◽  
Bibliometric Indicators ◽  
Pearson’S Correlation ◽  
Content Type ◽  
Positive Correlation ◽  
Pearson's Correlation ◽  
Different Characteristics ◽  
The Relationship

Purpose – The purpose of this paper is twofold. First, the study aims to investigate the relationship between the altmetric indicators from ResearchGate (RG) and the bibliometric indicators from the Scopus database. Second, the study seeks to examine the relationship amongst the RG altmetric indicators themselves. RG is a rich source of altmetric indicators such as Citations, RGScore, Impact Points, Profile Views, Publication Views, etc. Design/methodology/approach – For establishing whether RG metrics showed the same results as the established sources of metrics, Pearson’s correlation coefficients were calculated between the metrics provided by RG and the metrics obtained from Scopus. Pearson’s correlation coefficients were also calculated for the metrics provided by RG. The data were collected by visiting the profile pages of all the members who had an account in RG under the Department of Physics, Panjab University, Chandigarh (India). Findings – The study showed that most of the RG metrics showed strong positive correlation with the Scopus metrics, except for RGScore (RG) and Citations (Scopus), which showed moderate positive correlation. It was also found that the RG metrics showed moderate to strong positive correlation amongst each other. Research limitations/implications – The limitation of this study is that more and more scientists and researchers may join RG in the future, therefore the data may change. The study focuses on the members who had an account in RG under the Department of Physics, Panjab University, Chandigarh (India). Perhaps further studies can be conducted by increasing the sample size and by taking a different sample size having different characteristics. Originality/value – Being an emerging field, not much has been conducted in the area of altmetrics. Very few studies have been conducted on the reach of academic social networks like RG and their validity as sources of altmetric indicators like RGScore, Impact Points, etc. The findings offer insights to the question whether RG can be used as an alternative to traditional sources of bibliometric indicators, especially with reference to a rapidly developing country such as India.

scholarly journals Research on Population Spatiotemporal Aggregation Characteristics of a Small City: A Case Study on Shehong County Based on Baidu Heat Maps

2019 ◽  
Vol 11 (22) ◽  
pp. 6276 ◽  
Author(s):  
Deyi Feng ◽  
Lingli Tu ◽  
Zhongwei Sun
Keyword(s):  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Spatiotemporal Pattern ◽  
Heat Maps ◽  
Point Of Interest ◽  
Chi Squared ◽  
Agglomeration Effects ◽  
Spatiotemporal Aggregation ◽  
Population Aggregation ◽  
Map Data

Baidu heat maps can be used to explore the pattern of individual citizens conducting their activities and their agglomeration effects at the city scale. To investigate the spatiotemporal pattern of population aggregation and its relationship with land parcel attributes in small cities, we collected Baidu heat map data for a weekday and a weekend day in Shehong County and used Getis–Ord general G and the raster overlay methods to analyze population aggregation spatiotemporal characteristics. Chi-squared and Pearson correlation tests were used to analyze the correlation between population aggregation and land parcel attributes against three types of land parcel divisions: land use parcels, road network blocks, and grids. The results showed that, (1) for most hours of the workday, the degree of population aggregation was greater than on the weekend, and the fluctuation magnitude on the workday was higher as well. (2) On the weekday, people clustered and dispersed faster than on the weekend. (3) On the weekday and weekend, the spatial position of people aggregation was highly overlapping. (4) The correlation between the degree of population aggregation and the type of parcel was not significant. (5) Regarding different parcel unit sizes, the correlations between population aggregation degree and point of interest (POI) density, floor area ratio, and building density were significant and positively correlated, and the correlation coefficients increased as the grid size increased.

scholarly journals Anatomical axis validation of lower extremity for different deformities: A radiological study

2020 ◽  
Vol 8 ◽  
pp. 205031212092382
Author(s):  
Meric Unal ◽  
Sabriye Ercan ◽  
Aydin Budeyri ◽  
Uğur Toprak ◽  
Abdülkerim Şalkaci
Keyword(s):  
Lower Limb ◽  
Mechanical Axis ◽  
Correlation Coefficients ◽  
Strong Positive Correlation ◽  
Knee Alignment ◽  
Intra Class Correlation ◽  
X Ray ◽  
The Past ◽  
Radiology Assistant ◽  
Anatomical Axis

Aim: The aim of this study was to derive a pure, unbiased, reliable and accurate objective relationship between the local knee axis measurements through a short knee anteroposterior roentgenogram and the lower limb axis measurement through an orthoroentgenogram. Patients and Methods: Radiographs of 114 patients (114 knees) were evaluated by two independent raters for measurement of lower limb axis on an orthoroentgenogram and the local knee axis on short knee anteroposterior X-ray, which was derived by cropping the orthoroentgenogram by a blinded radiology assistant. The raters measured at two different time-points separated by an interval of 30-day period. Intra-rater and inter-rater reliabilities were calculated by intra-class correlation coefficients and three models were built to establish the relationships of X-ray anatomical axis with orthoroentgenogram anatomical axis, orthoroentgenogram anatomical axis with orthoroentgenogram mechanical axis and X-ray anatomical axis with orthoroentgenogram mechanical axis. Results: For three different measurements, intra-class correlation coefficients of Rater 2 were higher than 0.90 which shows perfect reliability, while that for Rater 1 was low. Furthermore, first measurements were more consistent than the second measurement. There was a strong positive correlation in all the three models except for varus cases in the last. Conclusion: The standardized correlation derived between the two different techniques for measuring knee alignment is fairly comparable with the studies in the past and would serve as a reliable template for future studies concerning relationships between the two, in addition to helping knee surgeons make more reliable and accurate interpretations through local knee axis measurements.

Hertzian Contact and Adhesion of Elastomers

1969 ◽  
Vol 91 (4) ◽  
pp. 732-737 ◽  
Author(s):  
Richard C. Drutowski
Keyword(s):  
Stress Distribution ◽  
Tensile Stress ◽  
Contact Area ◽  
Hard Sphere ◽  
Continuous Measurement ◽  
Hertzian Contact ◽  
Initial Contact ◽  
Circular Zone ◽  
Outer Annulus ◽  
Contact Size

The contact of a hard sphere with a flat elastomer is examined both analytically and experimentally when adhesive stresses are present. Use of a transparent spherical indenter enables continuous measurement of contact size while the samples are pulled apart. For any combination of load and contact area, the superposition of a Hertz and a Boussinesq stress distribution separates the contact into a circular zone under compression and an outer annulus under tension. During separation, while the contact size decreases and the tensile annulus becomes a larger percentage of the total contact, the average tensile stress remains constant. This average adhesive is a material property which is easily measured and is shown to be invariant with respect to indenter radius and initial contact pressure. An application of this analysis to opaque indenters is described.

A Model for Junction Growth of a Spherical Contact

2007 ◽  
Author(s):  
Victor Brizmer ◽  
Izhak Etsion ◽  
Yuri Kligerman
Keyword(s):  
Contact Zone ◽  
Contact Area ◽  
Gradual Increase ◽  
Initial Contact ◽  
Loss Of Stability ◽  
Theoretical Relation ◽  
Sphere Surface ◽  
Tangential Load ◽  
Spherical Contact ◽  
Tangential Stiffness

The evolution of the contact area (junction growth) of an elastic-plastic preloaded spherical contact subjected to an additional tangential loading is investigated theoretically. The normal preloading leads to the formation of a junction that can support additional tangential load. A gradual increase of this tangential load, while the normal preload remains constant, can incept plasticity of the contact zone in case the initial normal preload was elastic or enhance an existing one, thus lowering the tangential stiffness of the junction. Finally, the tangential stiffness approaches zero which corresponds to sliding inception (i.e. loss of stability). The evolution of the contact area during the tangential loading prior to sliding inception reveals an essential junction growth which depends on the magnitude of the normal preload. The mechanism causing this junction growth seems to be new points of the sphere surface, which originally lay outside of the initial contact area that are coming into contact with the rigid flat during the tangential loading. A theoretical relation is developed for the dependence of junction growth on the normal preload, which correlates well with some limited experiments.

A mechanics model of the compression of cells with finite initial contact area

Biorheology ◽  
1990 ◽  
Vol 27 (2) ◽  
pp. 225-240 ◽  
Author(s):  
Gao Qiong ◽  
R.E. Pitt ◽  
A. Ruina
Keyword(s):  
Contact Area ◽  
Initial Contact ◽  
Mechanics Model

Cross-cultural adaptation and clinical evaluation of a Korean version of the Work, Osteoarthritis or joint-Replacement Questionnaire

2019 ◽  
Vol 26 (5) ◽  
pp. 1-8
Author(s):  
Gyu-wan Lee ◽  
Chung-hwi Yi ◽  
Gyoung-mo Kim ◽  
Young-jung Lee ◽  
Jang-whon Yoon
Keyword(s):  
Factor Analysis ◽  
Internal Consistency ◽  
Joint Replacement ◽  
Cultural Adaptation ◽  
Assessment Tool ◽  
Correlation Coefficients ◽  
Cross Cultural ◽  
Strong Positive Correlation ◽  
Intra Class Correlation ◽  
Cross Cultural Adaptation

Background and aim The Work Osteoarthritis or joint-Replacement Questionnaire (WORQ) is a new assessment tool developed in the Netherlands. It needs translation and cross-cultural adaptation for use in each country. The aim of this study was to translate the Work Osteoarthritis or joint-Replacement Questionnaire into Korean and to verify its reliability and validity. Methods To evaluate the clinimetric quality of the Korean-WORQ, we performed tests for internal consistency (Cronbach's alpha), reliability (intra-class correlation coefficients) and concurrent validity (Spearman's correlation coefficient). Factor analysis was carried out to identify the principal components of the questionnaire. Findings Both the internal consistency and intra-class correlation coefficients showed the reliability of the Korean-WORQ to be excellent. The Korean-WORQ had a strong positive correlation with the Western Ontario and McMaster Universities Osteoarthritis Index and three components were extracted in factor analysis. Conclusions Based on these results, the Korean-WORQ seems to be a suitable questionnaire for assessing the disability levels of patients with knee injuries.

The Analysis of Contact Fatigue Behavior in Ni-Base Single Crystal Superalloy Turbine Blade Rabbet

2014 ◽  
Vol 633-634 ◽  
pp. 1104-1110
Author(s):  
Guo Cai Zhou ◽  
Hai Qing Pei
Keyword(s):  
Shear Stress ◽  
Single Crystal ◽  
Turbine Blade ◽  
Contact Area ◽  
Fatigue Behavior ◽  
Stress Gradient ◽  
Contact Fatigue ◽  
Tooth Contact ◽  
Rate Dependent ◽  
Single Crystal Turbine Blade

Based on the dislocation pile-up theory and the crystal plastic theory, a rate-dependent crystallographic plastic finite element method (FEM) was used to analyze the stress distribution in the contact zone of single crystal turbine blade rabbet. The FEM results show that the maximum stress and the maximum resolved shear stress location are in the upper edge of the first tooth contact area of the rabbet. The surface crack initiates in the edge and grows as the zigzag wave. The deflected angle of the plane defined by maximum resolved shear stress gradient direction and the upper edge of the first tooth contact area of the rabbet with respect to the Z axis is 35°. The fracture occurs along the {-1-11} plane. Fracture behavior of rabbet/groove modeling specimens made of nickel-based single crystal superalloys was studied by corresponding contact fatigue experiments. The initial place and developing direction of the fatigue crack observed from experiments are found to be in good agreement with the predicted results based FEM.

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