The Experts below are selected from a list of 2319 Experts worldwide ranked by ideXlab platform

Mary L Bouxsein - One of the best experts on this subject based on the ideXlab platform.

  • a new x ray based osteoporosis screening tool provides accurate and precise assessment of Phalanx Bone mineral content
    Journal of Clinical Densitometry, 1999
    Co-Authors: Daniel Michaeli, Alireza Mirshahi, Jonathan Singer, Frank G Rapa, David B Plass, Mary L Bouxsein
    Abstract:

    Abstract Many devices currently available for the assessment of osteoporosis require a significant capital investment, are not portable, and require specially trained operators. The objective of this study was to assess the accuracy and precision of a new tabletop dual-energy computed digital absorptiometry (CDA) device (accuDEXA TM , Schick Technologies, Long Island City, NY) designed to automatically and instantaneously assess Bone mineral content (BMC) and Bone mineral density (BMD) of the middle finger. BMC and BMD of 26 cadaveric forearms were measured by dual-energy X-ray absorptiometry, radiographic absorptiometry (RA), and CDA. accuDEXA measurements were repeated five times with and without repositioning on 10 forearms. The portion of the finger evaluated by accuDEXA was then excised, measurements of the specimen were again obtained using the accuDEXA device, and the specimen was incinerated to determine ash weight. BMC assessed by accuDEXA and by RA were strongly correlated with ash weight of the excised Phalanx specimens ( r 2 = 0.94 and r 2 =0.96, respectively). Short-term precision for BMD assessed by the accuDEXA device was 0.9% without repositioning, and 1.8% with repositioning. BMD determined by the accuDEXA device was strongly correlated with BMD of the hand and forearm ( r 2 = 0.56-0.69). Dual-energy CDA is a new Bone densitometry technique that provides rapid, precise, and accurate measurements of the middle Phalanx of the third finger. The technique may be useful for widespread testing of osteoporotic patients.

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

  • a new x ray based osteoporosis screening tool provides accurate and precise assessment of Phalanx Bone mineral content
    Journal of Clinical Densitometry, 1999
    Co-Authors: Daniel Michaeli, Alireza Mirshahi, Jonathan Singer, Frank G Rapa, David B Plass, Mary L Bouxsein
    Abstract:

    Abstract Many devices currently available for the assessment of osteoporosis require a significant capital investment, are not portable, and require specially trained operators. The objective of this study was to assess the accuracy and precision of a new tabletop dual-energy computed digital absorptiometry (CDA) device (accuDEXA TM , Schick Technologies, Long Island City, NY) designed to automatically and instantaneously assess Bone mineral content (BMC) and Bone mineral density (BMD) of the middle finger. BMC and BMD of 26 cadaveric forearms were measured by dual-energy X-ray absorptiometry, radiographic absorptiometry (RA), and CDA. accuDEXA measurements were repeated five times with and without repositioning on 10 forearms. The portion of the finger evaluated by accuDEXA was then excised, measurements of the specimen were again obtained using the accuDEXA device, and the specimen was incinerated to determine ash weight. BMC assessed by accuDEXA and by RA were strongly correlated with ash weight of the excised Phalanx specimens ( r 2 = 0.94 and r 2 =0.96, respectively). Short-term precision for BMD assessed by the accuDEXA device was 0.9% without repositioning, and 1.8% with repositioning. BMD determined by the accuDEXA device was strongly correlated with BMD of the hand and forearm ( r 2 = 0.56-0.69). Dual-energy CDA is a new Bone densitometry technique that provides rapid, precise, and accurate measurements of the middle Phalanx of the third finger. The technique may be useful for widespread testing of osteoporotic patients.

Sonia Duprey - One of the best experts on this subject based on the ideXlab platform.

  • MRI-based experimentations of fingertip flat compression: Geometrical measurements and finite element inverse simulations to investigate material property parameters
    Journal of Biomechanics, 2018
    Co-Authors: Jérémy Dallard, Xavier Merlhiot, Noémie Petitjean, Sonia Duprey
    Abstract:

    Modeling human-object interactions is a necessary step in the ergonomic assessment of products. Fingertip finite element models can help investigating these interactions, if they are built based on realistic geometrical data and material properties. The aim of this study was to investigate the fingertip geometry and its mechanical response under compression, and to identify the parameters of a hyperelastic material property associated to the fingertip soft tissues. Fingertip compression tests in an MRI device were performed on 5 subjects at either 2 or 4 N and at 15° or 50°. The MRI images allowed to document both the internal and external fingertip dimensions and to build 5 subject-specific finite element models. Simulations reproducing the fingertip compression tests were run to obtain the material property parameters of the soft tissues. Results indicated that two ellipses in the sagittal and longitudinal plane could describe the external fingertip geometry. The internal geometries indicated an averaged maximal thickness of soft tissues of 6.4 ± 0.8 mm and a 4 ± 1 mm height for the Phalanx Bone. The averaged deflections under loading went from 1.8 ± 0.3 mm at 2 N, 50° to 3.1 ± 0.2 mm at 4 N, 15°. Finally, the following set of parameters for a second order hyperelastic law to model the fingertip soft tissues was proposed: C01 = 0.59 ± 0.09 kPa and C20 = 2.65 ± 0.88 kPa. These data should facilitate further efforts on fingertip finite element modeling.

Muhammad Jafar Luthfi - One of the best experts on this subject based on the ideXlab platform.

  • anatomical study of bat s Phalanx Bone
    International Conference on Software Engineering, 2020
    Co-Authors: Fani Nurrizki, Hanifah Ika Ristiani, Novita Ambarwati, Muhammad Jafar Luthfi
    Abstract:

    Bats (Pteropus sp) are nocturnal animals. Bats are mammal that are able to fly, actively foraging at night. During the day time bats spend time for sleeping. It aims to keep the wings membran from sunlight. The habitat of this bat is on large trees. The foot of the bat is adapted to hang upside down, that causing an action against Phalanx that calls pressure. Each of Phalanx receives a different pressure so that it affect the anatomical structure. This condition present a biomechanical. This study aims to know the effect of pressure on the Phalanx. Observation are made by cleaning the Phalanx skin and cutting the Bones and then seen under the microscope with a magnification of 5x, measurement are taken. The result show that the pressure affect the Phalanx anatomical structure that is different thicknesses in each Phalanx.

Kurt D Hankenson - One of the best experts on this subject based on the ideXlab platform.

  • osteopathology in the equine distal Phalanx associated with the development and progression of laminitis
    Veterinary Pathology, 2015
    Co-Authors: Julie B. Engiles, Michael I Dishowitz, Hannah Galantinohomer, Raymond C Boston, D Mcdonald, Kurt D Hankenson
    Abstract:

    Although the equine distal Phalanx and hoof lamellae are biomechanically and physiologically integrated, bony changes in the distal Phalanx are poorly described in laminitis. The aims of this study were (1) to establish a laminitis grading scheme that can be applied to the wide spectrum of lesions seen in naturally occurring cases and (2) to measure and describe changes in the distal Phalanx associated with laminitis using micro–computed tomography (micro-CT) and histology. Thirty-six laminitic and normal feet from 15 performance and nonperformance horses were evaluated. A laminitis grading scheme based on radiographic, gross, histopathologic, and temporal parameters was developed. Laminitis severity grades generated by this scheme correlated well with clinical severity and coincided with decreased distal Phalanx Bone volume and density as measured by micro-CT. Laminitic hoof wall changes included progressive ventral rotation and distal displacement of the distal Phalanx with increased thickness of the st...

  • Osteopathology in the Equine Distal Phalanx Associated With the Development and Progression of Laminitis
    Veterinary pathology, 2015
    Co-Authors: Julie B. Engiles, Michael I Dishowitz, Raymond C Boston, D Mcdonald, Hannah Galantino-homer, Kurt D Hankenson
    Abstract:

    Although the equine distal Phalanx and hoof lamellae are biomechanically and physiologically integrated, bony changes in the distal Phalanx are poorly described in laminitis. The aims of this study were (1) to establish a laminitis grading scheme that can be applied to the wide spectrum of lesions seen in naturally occurring cases and (2) to measure and describe changes in the distal Phalanx associated with laminitis using micro-computed tomography (micro-CT) and histology. Thirty-six laminitic and normal feet from 15 performance and nonperformance horses were evaluated. A laminitis grading scheme based on radiographic, gross, histopathologic, and temporal parameters was developed. Laminitis severity grades generated by this scheme correlated well with clinical severity and coincided with decreased distal Phalanx Bone volume and density as measured by micro-CT. Laminitic hoof wall changes included progressive ventral rotation and distal displacement of the distal Phalanx with increased thickness of the stratum internum-corium tissues with lamellar wedge formation. Histologically, there was epidermal lamellar necrosis with basement membrane separation and dysplastic regeneration, including acanthosis and hyperkeratosis, corresponding to the lamellar wedge. The changes detected by micro-CT corresponded to microscopic findings in the Bone, including osteoclastic osteolysis of trabecular and osteonal Bone with medullary inflammation and fibrosis. Bone changes were identified in horses with mild/early stages of laminitis as well as severe/chronic stages. The authors conclude that distal phalangeal pathology is a quantifiable and significant component of laminitis pathology and may have important implications for early detection or therapeutic intervention of equine laminitis.