Development of a dual-energy X-ray absorptiometry-derived body volume equation in Hispanic adults for administering a four-compartment model

2020 ◽  
Vol 123 (12) ◽  
pp. 1373-1381 ◽  
Author(s):  
Brett S. Nickerson ◽  
Michael V. Fedewa ◽  
Cherilyn N. McLester ◽  
John R. McLester ◽  
Michael R. Esco
Keyword(s):  
Cross Validation ◽  
Dual Energy ◽  
Body Volume ◽  
Main Body ◽  
Validation Sample ◽  
Body Composition Assessment ◽  
X Ray ◽  
Hispanic Females ◽  
Hispanic Adults ◽  
The Cross

AbstractThe purpose of the present study was: (1) to develop a new dual-energy X-ray absorptiometry (DXA)-derived body volume (BV) equation with the GE-Lunar prodigy while utilising underwater weighing (UWW) as a criterion and (2) to cross-validate the novel DXA-derived BV equation (4C-DXANickerson), Wilson DXA-derived BV equation (4C-DXAWilson) and air displacement plethysmography (ADP)-derived BV (4C-ADP) in Hispanic adults. A total of 191 Hispanic adults (18–45 years) participated in the present study. The development sample consisted of 120 females and males (50 % females), whereas the cross-validation sample comprised of forty-one females and thirty males (n 71). Criterion body fat percentage (BF %) and fat-free mass (FFM) were determined using a four-compartment (4C) model with UWW as a criterion for BV (4C-UWW). 4C-DXANickerson, 4C-DXAWilson and 4C-ADP were compared against 4C-UWW in the cross-validation sample. 4C-DXANickerson, 4C-DXAWilson and 4C-ADP all produced similar validity statistics when compared with 4C-UWW in Hispanic males (all P > 0·05). 4C-DXANickerson also yielded similar BF % and FFM values as 4C-UWW when evaluating the mean differences (constant error (CE)) in Hispanic females (CE = –0·79 % and 0·38 kg; P = 0·060 and 0·174, respectively). However, 4C-DXAWilson produced significantly different BF % and FFM values (CE = 3·22 % and –2·20 kg, respectively; both P < 0·001). Additionally, 4C-DXAWilson yielded significant proportional bias when estimating BF % (P < 0·001), whereas 4C-ADP produced significant proportional bias for BF % and FFM (both P < 0·05) when evaluated in Hispanic females. The present study findings demonstrate that 4C-DXANickerson is a valid measure of BV in Hispanics and is recommended for use in clinics, where DXA is the main body composition assessment technique.

scholarly journals Ant Colony-Based Hyperparameter Optimisation in Total Variation Reconstruction in X-ray Computed Tomography

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 591
Author(s):  
Manasavee Lohvithee ◽  
Wenjuan Sun ◽  
Stephane Chretien ◽  
Manuchehr Soleimani
Keyword(s):  
Computed Tomography ◽  
Total Variation ◽  
Cross Validation ◽  
Ant Colony ◽  
Reference Image ◽  
X Ray ◽  
X Ray Computed ◽  
Hyperparameter Selection ◽  
The Cross ◽  
Optimal Set

In this paper, a computer-aided training method for hyperparameter selection of limited data X-ray computed tomography (XCT) reconstruction was proposed. The proposed method employed the ant colony optimisation (ACO) approach to assist in hyperparameter selection for the adaptive-weighted projection-controlled steepest descent (AwPCSD) algorithm, which is a total-variation (TV) based regularisation algorithm. During the implementation, there was a colony of artificial ants that swarm through the AwPCSD algorithm. Each ant chose a set of hyperparameters required for its iterative CT reconstruction and the correlation coefficient (CC) score was given for reconstructed images compared to the reference image. A colony of ants in one generation left a pheromone through its chosen path representing a choice of hyperparameters. Higher score means stronger pheromones/probabilities to attract more ants in the next generations. At the end of the implementation, the hyperparameter configuration with the highest score was chosen as an optimal set of hyperparameters. In the experimental results section, the reconstruction using hyperparameters from the proposed method was compared with results from three other cases: the conjugate gradient least square (CGLS), the AwPCSD algorithm using the set of arbitrary hyperparameters and the cross-validation method.The experiments showed that the results from the proposed method were superior to those of the CGLS algorithm and the AwPCSD algorithm using the set of arbitrary hyperparameters. Although the results of the ACO algorithm were slightly inferior to those of the cross-validation method as measured by the quantitative metrics, the ACO algorithm was over 10 times faster than cross—Validation. The optimal set of hyperparameters from the proposed method was also robust against an increase of noise in the data and can be applicable to different imaging samples with similar context. The ACO approach in the proposed method was able to identify optimal values of hyperparameters for a dataset and, as a result, produced a good quality reconstructed image from limited number of projection data. The proposed method in this work successfully solves a problem of hyperparameters selection, which is a major challenge in an implementation of TV based reconstruction algorithms.

Techniques For Assessment Of Body Composition In Health

2018 ◽  
Author(s):  
Carla M Prado ◽  
Camila LP Oliveira ◽  
M Cristina Gonzalez ◽  
Steven B Heymsfield
Keyword(s):  
Body Composition ◽  
Nutritional Status ◽  
Bioelectrical Impedance Analysis ◽  
Bioelectrical Impedance ◽  
Impedance Analysis ◽  
Dual Energy ◽  
Composition Analysis ◽  
Body Composition Assessment ◽  
Air Displacement Plethysmography ◽  
X Ray

Body composition assessment is an important tool in both clinical and research settings able to characterize the nutritional status of individuals in various physiologic and pathologic conditions. Health care professionals can use the information acquired by body composition analysis for the prevention and treatment of diseases, ultimately improving health status. Here we describe commonly used techniques to assess body composition in healthy individuals, including dual-energy x-ray absorptiometry, bioelectrical impedance analysis, air displacement plethysmography, and ultrasonography. Understanding the key underlying concept(s) of each assessment method, as well as its advantages and limitations, facilitates selection of the method of choice and the method of the compartment of interest. This review contains 5 figures, 3 tables and 52 references Key words: air displacement plethysmography, bioelectrical impedance analysis, body composition, disease, dual-energy x-ray absorptiometry, health, muscle mass, nutritional status, obesity, sarcopenia, ultrasound fat mass

scholarly journals Evaluation of dual-energy X-ray absorptiometry for body-composition assessment in piglets and term human neonates

1996 ◽  
Vol 63 (2) ◽  
pp. 157-163 ◽  
Author(s):  
J C Picaud ◽  
J Rigo ◽  
K Nyamugabo ◽  
J Milet ◽  
J Senterre
Keyword(s):  
Body Composition ◽  
Dual Energy ◽  
Body Composition Assessment ◽  
X Ray ◽  
Human Neonates

Validity of a Multi-compartment Body Composition Model Using Body Volume Derived from Dual-Energy X-ray Absorptiometry

2016 ◽  
Vol 48 ◽  
pp. 1036 ◽  
Author(s):  
Meredith Mock ◽  
Eric D. Ryan ◽  
Gena R. Gerstner ◽  
Andrew J. Tweedell ◽  
Craig R. Kleinberg ◽  
...  
Keyword(s):  
Body Composition ◽  
Dual Energy ◽  
Body Volume ◽  
X Ray

CROSS-VALIDATION OF BIOIMPEDANCE (BI) EQUATIONS FOR BRAZILIAN WOMEN USING DUAL-ENERGY X-RAY ABSORPTIOMETRY (DXA)

1999 ◽  
Vol 31 (Supplement) ◽  
pp. S200 ◽  
Author(s):  
M. M. Bottaro ◽  
V. H. Heyward ◽  
J. B. Lindolfo
Keyword(s):  
Cross Validation ◽  
Dual Energy ◽  
X Ray

scholarly journals Is Digital Image Plethysmographic (DIP) Acquisition a Valid New Tool for Preoperative Body Composition Assessment? A Validation by Dual-energy X-ray Absorptiometry

2006 ◽  
Vol 16 (5) ◽  
pp. 560-566 ◽  
Author(s):  
Nicola Di Lorenzo ◽  
Michele Servidio ◽  
Laura Di Renzo ◽  
Carmine Orlandi ◽  
Giorgio Coscarella ◽  
...  
Keyword(s):  
Body Composition ◽  
Digital Image ◽  
Dual Energy ◽  
Body Composition Assessment ◽  
X Ray

Development of a Creativity Scale for the Adjective Check List

1969 ◽  
Vol 25 (1) ◽  
pp. 87-92 ◽  
Author(s):  
James M. Smith ◽  
Charles E. Schaefer
Keyword(s):  
Cross Validation ◽  
Validation Sample ◽  
Check List ◽  
Initial Sample ◽  
Adjective Check List ◽  
Select Group ◽  
The Cross ◽  
And Control ◽  
Item Scale ◽  
General Creativity

Creativity scales for the Adjective Check List (ACL) were developed and cross-validated. First, through the use of item analyses, separate creativity scales were developed for each of 4 sex by specialty field groups in an initial sample of adolescents. Each of these scales successfully discriminated creative and control Ss in the cross-validation sample. Subsequently, 2 general creativity scales were formed from the data of the initial sample by selecting only those adjectives which differentiated creative and control Ss across sex and specialty field. The 2 general scales, an 8-item scale and a 27-item scale, also proved successful in discriminating creative and control Ss in the cross-validation sample. In general, the use of the ACL creativity scales developed in this study proved more effective in differentiating creative and control Ss than did a select group of currently available ACL scales. A comparison of the validity of these new creativity scales indicated that the 27-item scale appears to be most promising.

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