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Daniel R. Jeske - One of the best experts on this subject based on the ideXlab platform.

  • Construction, visualization and application of Neutral Zone classifiers:
    Statistical methods in medical research, 2019
    Co-Authors: Daniel R. Jeske, Zhiwei Zhang, Steven S. Smith
    Abstract:

    When the potential for making accurate classifications with a statistical classifier is limited, a Neutral Zone classifier can be constructed by adding a no-decision option as a classification outc...

  • Bayes Neutral Zone Classifiers With Applications to Nonparametric Unsupervised Settings
    Journal of Agricultural Biological and Environmental Statistics, 2012
    Co-Authors: Scott Benecke, Daniel R. Jeske, Paul Reugger, James Borneman
    Abstract:

    Neutral Zone classifiers allow for a region of Neutrality when there is inadequate information to assign a predicted class with suitable confidence. A Neutral Zone classifier is defined by classification regions that trade off the cost of an incorrect classification against the cost of remaining Neutral. In this paper, we derive a Bayes Neutral Zone classifier and demonstrate that it outperforms previous Neutral Zone classifiers with respect to the expected cost of misclassifications and also with respect to computational complexity. We apply the Neutral Zone classifier to a microbial community profiling application in which no training data are available, thereby illustrating how it can be extended to unsupervised settings. This article has supplementary material online.

  • Neutral Zone Classifiers Using a Decision-Theoretic Approach With Application to DNA Array Analyses.
    Journal of agricultural biological and environmental statistics, 2010
    Co-Authors: Daniel R. Jeske, Paul M. Ruegger, James Borneman
    Abstract:

    Two-class Neutral Zone classifiers were recently proposed for use in microbial community profiling applications. These classifiers allow a region of Neutrality for cases where probe hybridization outcomes are too ambiguous to have adequate confidence in assigning a “binding” or “no binding” result. In this paper, we generalize the idea of Neutral Zone classifiers to an arbitrary number of classes and apply it to improve the process of microbial community profiling by considering a third class for the outcome of probe hybridization experiments, “partial binding.” We introduce a family of class distributions that uses a mixture of Gaussian distributions as a model for a Box–Cox power transformation of the raw intensity measurements. Stratified cross-validation analyses are used to assess the efficacy of the proposed three-class Neutral Zone classifier. This article has supplementary material online.

Steven S. Smith - One of the best experts on this subject based on the ideXlab platform.

Shweta Magadum - One of the best experts on this subject based on the ideXlab platform.

  • Enhancement of stability for mandibular complete denture prosthesis in atrophied ridge with Neutral Zone technique — A case report
    Journal of Advanced Oral Research, 2011
    Co-Authors: Viraj Patil, Rajendra Basavaraj Hallikerimath, Shweta Magadum
    Abstract:

    The Neutral Zone technique is not a new but a very valuable technique, it is an alternative approaches in constructing stable complete denture in case of a highly atrophic mandible. The main aim of the Neutral Zone technique is to construct denture in muscle harmony, so that it does not get displaced during the actions of the muscles surrounding as the actions of swallowing, mastication, speech and so on. Key words—Neutral Zone, Atrophic mandible. Introduction: The goal of dentistry is for patients to keep all their teeth throughout their lives in health and comfort. If the teeth are lost despite all efforts to save them, a restoration should be made in such a manner as to function efficiently and comfortably in harmony with the muscles of the stomatognathic system and the temporomandibular joints. With the increase in the life expectancy of the population, the numbers of complex complete denture cases also have been increasing. The treatment for these complex complete denture cases should be different from those of traditional complete dentures. In case of Atrophic mandible, Dental implants may provide stabilization of mandibular complete dentures, but in cases when it is not possible to provide implants on the grounds of medical risks, economic limitations or patients attitudes, an alternative technique should be thought. The Neutral Zone Technique is an alternative approach for these cases. The Neutral Zone technique is not new, but is one that is valuable yet not practiced. The Neutral Zone has been defined as the area in the mouth where during function, the forces of the tongue pressing outwards are Neutralized by the forces of the cheek and lips pressing inwards. The aim of the Neutral Zone is to construct a denture in muscle balance. If the denture is out of harmony with the Neutral Zone, it will result in instability, interference with function or some degree of discomfort. Thus Neutral Zone must be evaluated as an important factor before aligning the teeth in complete denture or partial denture. This is the Zone where the natural dentition exists. As the mandible atrophies at a greater rate than the maxilla and has less residual ridge for retention and support, the lower denture commonly presents the most difficulties with pain and looseness being the most common complaints. The Neutral Zone technique is most effective for patients who have had numerous unstable and nonretentive lower complete dentures. These patients usually have a highly atrophic mandible and there has been difficulty in positioning the teeth to produce a stable denture. The Neutral Zone approach has been used for patients who have had a partial glossectomy, mandibular resections or motor nerve damage to the tongue– which have led to either atypical movement or an unfavorable denture bearing area. Background: Sir Wilfred Fish in 1931 first described the influence of the polished surface on retention and stability. He also described how dentures should be constructed in the ‘dead space’, which later became as the

James Borneman - One of the best experts on this subject based on the ideXlab platform.

  • Bayes Neutral Zone Classifiers With Applications to Nonparametric Unsupervised Settings
    Journal of Agricultural Biological and Environmental Statistics, 2012
    Co-Authors: Scott Benecke, Daniel R. Jeske, Paul Reugger, James Borneman
    Abstract:

    Neutral Zone classifiers allow for a region of Neutrality when there is inadequate information to assign a predicted class with suitable confidence. A Neutral Zone classifier is defined by classification regions that trade off the cost of an incorrect classification against the cost of remaining Neutral. In this paper, we derive a Bayes Neutral Zone classifier and demonstrate that it outperforms previous Neutral Zone classifiers with respect to the expected cost of misclassifications and also with respect to computational complexity. We apply the Neutral Zone classifier to a microbial community profiling application in which no training data are available, thereby illustrating how it can be extended to unsupervised settings. This article has supplementary material online.

  • Neutral Zone Classifiers Using a Decision-Theoretic Approach With Application to DNA Array Analyses.
    Journal of agricultural biological and environmental statistics, 2010
    Co-Authors: Daniel R. Jeske, Paul M. Ruegger, James Borneman
    Abstract:

    Two-class Neutral Zone classifiers were recently proposed for use in microbial community profiling applications. These classifiers allow a region of Neutrality for cases where probe hybridization outcomes are too ambiguous to have adequate confidence in assigning a “binding” or “no binding” result. In this paper, we generalize the idea of Neutral Zone classifiers to an arbitrary number of classes and apply it to improve the process of microbial community profiling by considering a third class for the outcome of probe hybridization experiments, “partial binding.” We introduce a family of class distributions that uses a mixture of Gaussian distributions as a model for a Box–Cox power transformation of the raw intensity measurements. Stratified cross-validation analyses are used to assess the efficacy of the proposed three-class Neutral Zone classifier. This article has supplementary material online.

Mark J. Pearcy - One of the best experts on this subject based on the ideXlab platform.

  • The Neutral Zone in Lumbar Joint Movements and How it is Affected by Preload
    Journal of Biomechanics, 2006
    Co-Authors: H. De Visser, Clayton J. Adam, Mark J. Pearcy
    Abstract:

    Introduction It is important to understand the mechanics of the lumbar spine, as it has been shown that much low back pain is attributable to mechanical factors. One important aspect of spinal mechanics is the Neutral Zone, defined as a region of little or no resistance to motion on either side of the Neutral position for a motion segment. If the Neutral Zone is a significant feature of intervertebral joint mechanics then the spinal joints will have little intrinsic stability and rely on muscles to control their movement around the Neutral position. This has significant implications for our understanding of how degenerative changes to the spinal joints might destabilise the spine. This study was performed to characterise the size of the Neutral Zone and the effect of axial preload for different spinal motions. Methods Using a 6 degree-of-freedom (DOF) ABB industrial robot incorporating a 6-DOF JR3 force sensor, six isolated ovine lumbar joint segments were subjected to 5 repetitive movements in 3 directions (6° extension / 15° flexion, +/- 7° lateral bend, +/- 3° axial twist) with 4 different preloads (0, 150, 300, 450N) under 2 conditions (facet joints intact and facets removed). For each direction, the fixed axis about which the joint would rotate with a minimal motion-opposing moment was determined in advance. In accordance with a previous study by this group, the Neutral Zone was defined as the region where absolute rotational stiffness is less than 0.05 Nm/°. Results When moving from 6° of extension to -15° (flexion) a Neutral Zone was usually observed starting around 0° and continuing as far as -8 or -9°. The Neutral Zone was in the same region when moving in the opposite direction, except when the specimen showed a considerable amount of hysteresis, in which case the Neutral Zone could start as early as -11° or -12° and usually continued to -2°or -3°. Increasing preload usually made the joint stiffer in the regions outside the Neutral Zone, but did not affect the Neutral Zone itself. If present without preload, hysteresis usually increased with increasing preload. In lateral bend and axial twist no Neutral Zone was generally observed. In lateral bend the stiffness gradually increased with rotation, whereas in axial twist the stiffness was usually constant over the range of movement. For all movements, the only effect of facet removal was a constant reduction in stiffness over the whole movement. For lateral bend this meant that the stiffness around 0° usually would drop below the threshold of 0.05Nm/°, hence creating a Neutral Zone extending over a couple of degrees. Discussion Ovine spinal joints have a region where there is little to no resistance to flexion/extension. This region can be in excess of 10°. This means in their Neutral position, the individual spinal joints have virtually no stability and the spine depends on other measures such as muscle activation to maintain stability in the sagittal plane. For lateral bend there is a region of little resistance as well, but it is not nearly as profound as in flexion/extension.

  • Defining the Neutral Zone of Sheep Intervertebral Joints During Dynamic Motions: An In Vitro Study
    Clinical biomechanics (Bristol Avon), 2003
    Co-Authors: Rosemary E. Thompson, T.m. Barker, Mark J. Pearcy
    Abstract:

    Abstract Objective . To make an experimental assessment of the Neutral Zone of intervertebral joints during dynamic spinal motion in flexion/extension, lateral bending and axial rotation and to develop a criterion for its definition. Design . Dynamic mechanical testing of sheep intervertebral joints with a six-degree of freedom robotic facility under position control. Background . The Neutral Zone is defined as a region of no or little resistance to motion in the middle of an intervertebral joint’s range of movement. Previous studies have used quasi-static loading regimes that do not model physiological activity. This study simulated physiological movements using a robotic testing facility to address this issue. Methods . Five spines from mature sheep were used and three motion segments were tested from each spine. The robotic facility enabled the testing regime to be defined for each individual joint based on its geometry. The joints were tested by cycling through the full range of physiological movement in flexion/extension, lateral bending and axial rotation. Results . A Neutral Zone was found to exist during dynamic movements only in flexion/extension. The results suggested that a Neutral Zone does not exist in lateral bending or axial rotation. The zygapophysial joints were shown to be significant in determining the mechanics of the intervertebral joints as their removal increased the Neutral Zone in all cases. A new criterion for defining the size of the Neutral Zone during dynamic motion was proposed and its implications for spinal movements in life discussed. Conclusions . A Neutral Zone exists in flexion/extension during dynamic movements of intervertebral joints and is a feature of the natural range of joint motion. This has important implications for the muscular control of the spine consisting of several intrinsically lax joints stacked on one another. Relevance The existence of a Neutral Zone is a feature of the natural range of joint motion and requires complex control of intervertebral joints by the spinal muscles. Defining the biomechanical response throughout the physiological range of motion (RoM) is important in understanding possible injury and rehabilitation mechanisms.

  • DEFINING THE Neutral Zone OF INTERVERTEBRAL JOINTS USING A ROBOTIC TESTING FACILITY
    2002
    Co-Authors: Rosemary E. Thompson, T.m. Barker, Mark J. Pearcy
    Abstract:

    Introduction: the Neutral Zone is defined as a region of no or little resistance to motion in the middle of an intervertebral joint’s range of movement. Previous studies have used quasistatic loading regimes that do not model physiological activity[1][1]. The aim of the present study was to assess experimentally the existence of the Neutral Zone of intervertebral joints during spinal motion in flexion/extension, lateral bending and axial rotation during physiological movements simulated using a robotic testing facility. Sheep intervertebral joints were used as they have been shown to exhibit similar mechanical behaviour to human joints[2][2]. Methods: five spines from mature sheep were used. Three specimens were tested from each spine to simulate human l1/2, l3/4 and l4/5 intervertebral joints. The robotic facility enabled the testing regime to be defined for each individual joint based on its geometry. The joints were tested by cycling through the full range of physiological movement in flexion/extension, lateral bending and axial rotation. Results: a Neutral Zone was found to exist during dynamic movements only in flexion/extension. The results were equivocal for lateral bending and suggested that a Neutral Zone does not exist in axial rotation. The zygapophysial joints were shown to be significant in determining the mechanics of the intervertebral joints as their removal increased the Neutral Zone in all cases. A criterion for defining the size of the Neutral Zone was proposed. Conclusions: a Neutral Zone exists in flexion/extension during dynamic movements of intervertebral joints. This has important implications for the muscular control of the spine consisting of several intrinsically lax joints stacked on one another. [1]: #ref-1 [2]: #ref-2