Measurement Of Body Volume Research Articles

Validity of A-Mode Ultrasound for Estimating Body Fat Percentage of Young Adult Athletes: A Multicomponent Model Study.

This study compared %BFUS to %BF4C in young adult athletes. University club sport athletes (86 women, 138 men) from a variety of teams participated. ADP, DXA, and bioimpedance spectroscopy were used to measure body volume, bone mineral content, and total body water, respectively, for the 4C model. Ultrasound measurements were taken at three sites to estimate %BFUS. Comparisons between %BFUS and %BF4C were evaluated with Pearson correlation, paired t-test, linear regression, equivalence testing, and plots of individual errors. For the combined sample of men and women (N = 224), the two methods were highly correlated (r = 0.93) with a constant error (CE) of 0.8% BF (P < .001) and standard error of estimate (SEE) of 3.0% BF. The 90% confidence intervals of the mean difference (0.47 to 1.17) were well within the ±2% BF limits for equivalence testing, and no bias was evident from the error plot. However, equivalence testing failed to remain inside the ±2% BF range for women, and the prediction errors for women (CE = 1.9% BF, P < .001, SEE = 3.2% BF) were larger than for men (CE = 0.1% BF, P = .597, SEE = 2.8% BF). Overall, the %BFUS errors were low, suggesting that A-mode ultrasound is a valid field measure of %BF for young adult athletes. Accuracy is better for men than women.

Anti-tumor property of Argemone mexicana leaves methanol extracts against 7, 12- Dimethylbenz[a]anthracene (DMBA) induced mammary tumors in experimental rats

Background: Breast cancer is a complex and multistage process. Many natural compounds are available for an effective and efficient alternative method against breast cancer. This study focused on the anti-cancer activity of Argemone mexicana leaf extract on Dimethylbenz[a]anthracene (DMBA)-induced mammary tumors in experimental rats. Materials and Methods: Argemone mexicana Leaves (AML) were collected, extracted by soxhlet apparatus with methanol solvent, and analyzed by Gas Chromatography and Mass-Spectroscopy (GCMS). Healthy Female Sprague-Dawley rats (7-8 weeks and 100 ± 20 g) were divided in five groups and used to induce mammary tumors by DMBA [25 mg/kg/ Subcutaneous (s.c.)]. After developing a palpable nodule (10-12 weeks after DMBA), the rats were treated with AML extract [200 and 400 mg/kg/Body Weight (b.w.)] and Tamoxifen (TAM 10 mg/kg) orally for 12 weeks. Body weight, tumor weight and volume measurements, lipid peroxidation, antioxidant and tumor marker [Carcinoembryonic Antigen (CEA)] levels, and histological investigations were assessed. Results: Following AML treatment, there was a reduction in weight and volume (P&lt; 0.01) of breast tumor, as well as a significant decrease in levels of lipid peroxidation and tumor marker CEA (P &lt; 0.001) and improved Superoxide Dismutase (SOD), Reduced glutathione (GSH), and caspase levels (P &lt; 0.001). In cytological results, AML improved the cellular architecture, and significant restoration in histopathological examinations revealed a tumor with minimal glandular epithelium proliferation, a decrease in mitotic figures, and nuclear alterations. Conclusion: The study suggests that AML extract has a chemoprotective effect against DMBA-induced mammary tumors in experimental animals, specifying its possibility as a therapeutic agent for breast cancer treatment.

Comparison of the Watson formula and bioimpedance spectroscopy for measuring body volume and calculating kt/V in patients with peritoneal dialysis

Background: Ascertaining the total body water (V), usually obtained by the Watson formula or bioimpedance spectroscopy (BIS), is crucial for the calculation of Kt/V in patients with peritoneal dialysis (PD). The aim of our study was to compare two different methods of determining V and explore which one is suitable for clinical application. Methods: This was a retrospective observational study. V was determined using the Watson formula (Vwat) and BIS (Vbis). The differences between Vbis and Vwat and between Kt/Vbis and Kt/Vwat were assessed. The patients were allocated to different groups according to the Kt/Vwat and Kt/Vbis values. Clinical parameters were compared between these groups to investigate which method of obtaining the Kt/V value was more suitable. Results: 150 patients on PD were included. Vwat was significantly higher than Vbis, apart from in female patients with volume overload. Consequently, weekly Kt/Vwat was lower than Kt/Vbis in these patients. A significant negative correlation between mean Vwat-Vbis and overhydration values was also found. Moreover, through uniform manifold approximation and projection analysis, a clustering tendency between patients in the adequate group with both Kt/Vwat and Kt/Vbis > =1.7 and patients in the inconsistent group with Kt/Vwat <1.7 and Kt/Vbis > =1.7 was identified, suggesting that their clinical features were similar. Conclusion There were significant differences between Vwat and Vbis and between Kt/Vwat and Kt/Vbis. Kt/Vwat may underestimate small-solute dialysis adequacy in most cases. Kt/Vbis instead of Kt/Vwat could be accounted for in creating individualized dialysis prescriptions if the patient has no obvious clinical symptoms.

Predição do peso corporal de cabras da raça Alpina por meio da medida do volume corporal

ABSTRACT The objective was to estimate the body weight (BW) of Brown Alpine goats by means of body volume (BV) measurements. We used 132 pieces of information with measurements of BW, body length (BL) and thoracic perimeter (TP) from 22 goats evaluated fortnightly, between March and May 2023. Based on this information, the BV of the animals was calculated. Three mathematical models were evaluated - a linear model, a quadratic model, and an exponential model - with the measurement of BV. The goodness of fit of the equations was evaluated using the coefficient of determination (R2), mean square error (MSE) and root of the MSE (RMSE). The predictive ability of the models was evaluated by k-fold cross-validation (k = 10). A high positive correlation between BW and TP (r = 0.95) and BL (r = 0.94) was observed. The correlation between BW and BV was higher than the other correlations (r = 0.98). The linear model showed the lowest values of MSE (9.49) and RMSE (3.08). In the cross-validation, the linear and quadratic models presented estimates of the mean BW and the standard deviation of this weight similar to the real data, and high R2 values (0.95) of the data predicted by the observed ones. The analysis of the coefficient of correlation and concordance (CCC) also showed that these models have accuracy and precision (CCC &gt; 0.95). Thus, the linear and quadratic models estimate the body weight of Brown Alpine goats with precision and accuracy.

Neuroplasticity in honey bee brains: An enhanced micro-computed tomography protocol for precise mushroom body volume measurement

BackgroundIn insect brains, mushroom bodies are associated with memory and learning behavior. It has been demonstrated that the volume of the mushroom bodies in the brain of a worker honey bee changes during the adult stage. Changes in mushroom body volume imply high neuroplasticity in the brains and may be related to the age polyethism of honey bees. A suitable volume measurement method is needed to understand the correlation between behavioral changes and mushroom body volume changes in honey bees. New methodWe developed a new protocol for insect micro-computed tomography by modifying a previously reported method. Permount™ mounting medium was used as the embedding medium for micro-computed tomography scanning. ResultsThis protocol can generate images with high contrast inside the brain and reduce the marked shape changes during specimen processing. From the resulting high-contrast images, we used freeware to generate a three-dimensional model and calculate the volumes of the mushroom bodies in honey bees. The measured volumes of the mushroom bodies were larger than the values reported in most previous studies. There was no significant difference between the left and right mushroom body volumes, but the volumes of honey bee mushroom bodies significantly increased with age. Comparison with existing methodsPrevious protocols for micro-computed tomography using dried samples would cause brain shrinkage; protocols using ethanol-preserved or resin-embedded samples generated images with lower contrast. ConclusionsThe embedding protocol for micro-computed tomography is suitable for calculating volume of the mushroom bodies in honey bee brains.

Development and validation of a rapid multicompartment body composition model using 3-dimensional optical imaging and bioelectrical impedance analysis

Background & AimsThe multicompartment approach to body composition modeling provides a more precise quantification of body compartments in healthy and clinical populations. We sought to develop and validate a simplified and accessible multicompartment body composition model using 3-dimensional optical (3DO) imaging and bioelectrical impedance analysis (BIA). MethodsSamples of adults and collegiate-aged student-athletes were recruited for model calibration. For the criterion multicompartment model (Wang-5C), participants received measures of scale weight, body volume (BV) via air displacement, total body water (TBW) via deuterium dilution, and bone mineral content (BMC) via dual energy x-ray absorptiometry. The candidate model (3DO-5C) used stepwise linear regression to derive surrogate measures of BV using 3DO, TBW using BIA, and BMC using demographics. Test-retest precision of the candidate model was assessed via root mean square error (RMSE). The 3DO-5C model was compared to criterion via mean difference, concordance correlation coefficient (CCC), and Bland-Altman analysis. This model was then validated using a separate dataset of 20 adults. Results67 (31 female) participants were used to build the 3DO-5C model. Fat-free mass (FFM) estimates from Wang-5C (60.1 ± 13.4 kg) and 3DO-5C (60.3 ± 13.4 kg) showed no significant mean difference (-0.2 ± 2.0 kg; 95% limits of agreement [LOA] -4.3 to +3.8) and the CCC was 0.99 with a similar effect in fat mass that reflected the difference in FFM measures. In the validation dataset, the 3DO-5C model showed no significant mean difference (0.0 ± 2.5 kg; 95% LOA -3.6 to +3.7) for FFM with almost perfect equivalence (CCC = 0.99) compared to the criterion Wang-5C. Test-retest precision (RMSE = 0.73 kg FFM) supports the use of this model for more frequent testing in order to monitor body composition change over time. ConclusionsBody composition estimates provided by the 3DO-5C model are precise and accurate to criterion methods when correcting for field calibrations. The 3DO-5C approach offers a rapid, cost-effective, and accessible method of body composition assessment that can be used broadly to guide nutrition and exercise recommendations in athletic settings and clinical practice.

Marine mammal morphometrics: 3D modeling and estimation validation

Techniques of 3D modeling have earned increasing popularity in scientific studies as they offered unprecedented traits in representing objects. As with all mathematical models, the 3D model will be useful once its accuracy has been validated with direct measurements and the robustness of its predictive capability tested. Although measures of body mass and volume are essential to comprehend the life history of animals, such morphometrics, especially total volume, are challenging to obtain from marine mammals due to their elusive nature, aquatic lifestyle, and large size. In this study, accurate measurements of body volume were directly detected from fresh carcasses of eleven finless porpoises (Neophocaena asiaeorientalis sunameri) and used to validate 3D models recreated from the same animals using Blender 3D graphics. Published models using truncated cones or elliptical shapes, based on 3, 5, 8, or 19 measurements of girths or heights &amp;amp; widths along the body, were also applied to porpoises to verify their accuracy. The Blender-generated 3D model produced the most accurate estimates of body volume compared to conventional truncated models, with a mean error of only 2.5% to the direct volume measurements. When photogrammetric images are available, the model can predict the body volumes based on total length alone. Similar accuracy was possible with the elliptical model using 19 height &amp;amp; width measurements (5% increments in total length). However, significant (p &amp;lt; 0.001) inaccuracy resulted from truncated models with 3, 5, or 8 girth measurements and elliptical models with 3 or 5 height &amp;amp; width measurements, and the accuracy of these models also decreased significantly as the number of measurement sites was reduced. Moreover, Blender 3D models can be extrapolated to animals with images absent, and such predicted volumes were tested to be trustworthy (overall skill = 0.998, r = 0.998, p &amp;lt; 0.01). Therefore, we recommend that researchers use either digital 3D models or elliptical models with 5% increments sectioning the torso to obtain accurate estimates of the body volumes of free-ranging marine mammals.

Estimating body weight and body condition score of mature beef cows using depth images.

Obtaining accurate body weight (BW) is crucial for management decisions yet can be a challenge for cow-calf producers. Fast-evolving technologies such as depth sensing have been identified as low-cost sensors for agricultural applications but have not been widely validated for U.S. beef cattle. This study aimed to (1) estimate the body volume of mature beef cows from depth images, (2) quantify BW and metabolic weight (MBW) from image-projected body volume, and (3) classify body condition scores (BCS) from image-obtained measurements using a machine-learning-based approach. Fifty-eight crossbred cows with a mean BW of 410.0 ± 60.3 kg and were between 4 and 6 yr of age were used for data collection between May and December 2021. A low-cost, commercially available depth sensor was used to collect top-view depth images. Images were processed to obtain cattle biometric measurements, including MBW, body length, average height, maximum body width, dorsal area, and projected body volume. The dataset was partitioned into training and testing datasets using an 80%:20% ratio. Using the training dataset, linear regression models were developed between image-projected body volume and BW measurements. Results were used to test BW predictions for the testing dataset. A machine-learning-based multivariate analysis was performed with 29 algorithms from eight classifiers to classify BCS using multiple inputs conveniently obtained from the cows and the depth images. A feature selection algorithm was performed to rank the relevance of each input to the BCS. Results demonstrated a strong positive correlation between the image-projected cow body volume and the measured BW (r = 0.9166). The regression between the cow body volume and the measured BW had a co-efficient of determination (R2) of 0.83 and a 19.2 ± 13.50 kg mean absolute error (MAE) of prediction. When applying the regression to the testing dataset, an increase in the MAE of the predicted BW (22.7 ± 13.44 kg) but a slightly improved R2 (0.8661) was noted. Among all algorithms, the Bagged Tree model in the Ensemble class had the best performance and was used to classify BCS. Classification results demonstrate the model failed to predict any BCS lower than 4.5, while it accurately classified the BCS with a true prediction rate of 60%, 63.6%, and 50% for BCS between 4.75 and 5, 5.25 and 5.5, and 5.75 and 6, respectively. This study validated using depth imaging to accurately predict BW and classify BCS of U.S. beef cow herds.

Dual X-ray absorptiometry-derived total and regional body volume.

Although dual X-ray absorptiometry (DXA) has been used to determine total body volume, using DXA to determine regional (i.e., arm and leg) volumes needs further assessment. Thus, the aim of the present study is to evaluate the validity of total and regional DXA-derived body volume compared to a traditional method for measuring body volume. A total of 30 males and females (Age: 25.9±4.0yrs; Height: 1.75±0.10m; Weight: 70.98±14.02kg) underwent one whole body DXA scan, underwater weighing, and regional measures of volume via water displacement. Manually created DXA region of interest boxes were used to determine regional DXA body composition. Total body volume was calculated by taking the participant's dry weight and dividing it by the average density from underwater weighing. Linear regression models with body volume from underwater weighing for total body volume and water displacement for regional volume as the dependent variable and DXA lean mass, fat mass, and bone mass as independent variables created total and regional DXA-derived body volume. T-tests assessed DXA-derived body volume to the traditional method of body volume assessment. Regression models were cross-validated using the Repeated k-fold Cross Validation method. DXA-derived total body volume was not significantly (p=0.999) different from total body volume measured via total body water displacement. In addition, both arm and leg regional DXA-derived volume was not significantly different (p=0.999) compared to regional volume measured by regional water displacement. Cross-validation of each model produced R2 values of 0.992, 0.923, and 0.932 for total body, arm, and leg, respectively. The DXA may be used as valid method for estimating total and regional body volume. Thus, these results expand the DXA's capabilities and potentially allow for a convenient regional four-compartment model with DXA-derived regional volume.

Assessment of efficacy and safety of volanesorsen for treatment of metabolic complications in patients with familial partial lipodystrophy: Results of the BROADEN study: Volanesorsen in FPLD; The BROADEN Study

BackgroundVolanesorsen, an antisense oligonucleotide, is designed to inhibit hepatic apolipoprotein C-III synthesis and reduce plasma apolipoprotein C-III and triglyceride concentrations. ObjectiveThe present study assessed efficacy and safety of volanesorsen in patients with familial partial lipodystrophy (FPLD) and concomitant hypertriglyceridemia and diabetes. MethodsBROADEN was a randomized, placebo-controlled, phase 2/3, 52-week study with open-label extension and post-treatment follow-up periods. Patients received weekly subcutaneous volanesorsen 300 mg or placebo. The primary endpoint was percent change from baseline in fasting triglycerides at 3 months. Secondary endpoints included relative percent change in hepatic fat fraction (HFF), visceral adiposity, and glycated hemoglobin levels. ResultsForty patients (11 men, 29 women) were enrolled, majority of whom were aged <65 years (mean, 47 years) and White. Least squares mean (LSM) percent change in triglycerides from baseline to 3 months was −88% (95% CI, −134 to −43) in the volanesorsen group versus –22% (95% CI, −61 to 18) in the placebo group, with a difference in LSM of −67% (95% CI, –104 to –30; P=0.0009). Volanesorsen induced a significant LSM relative reduction in HFF of 53% at month 12 versus placebo (observed mean [SD]: 9.7 [7.65] vs. 18.0 [8.89]; P=0.0039). No statistically significant changes were noted in body volume measurements (fat, liver, spleen, visceral/subcutaneous adipose tissue) or glycated hemoglobin. Serious adverse events in patients assigned to volanesorsen included 1 case each of sarcoidosis, anaphylactic reaction, and systemic inflammatory response syndrome. ConclusionIn BROADEN, volanesorsen significantly reduced serum triglyceride levels and hepatic steatosis in patients with FPLD.

Tracking wildlife energy dynamics with unoccupied aircraft systems and three‐dimensional photogrammetry

Abstract We present a novel application using unoccupied aircraft systems (UAS; drones) for structure‐from‐motion three‐dimensional (3‐D) photogrammetry of multiple, free‐living animals simultaneously. Pinnipeds reliably haul out on shore for pupping and breeding each year, accompanied by dramatic female‐to‐pup mass transfer over a short lactation period and males lose mass while defending mating territories. This provides a tractable study system for validating the use of UAS as a non‐invasive tool for tracking energy dynamics in wild populations. UAS imagery of grey seals Halichoerus grypus was collected at Saddle Island, Nova Scotia. A multirotor UAS was piloted in 360‐degree orbits around relatively dense animal aggregations and georeferenced images were used for construction of a 3‐D point cloud, orthomosaic and Digital Surface Model for animal volumetric measurements. Directly following UAS survey, a subset of adult females were hand‐measured (morphometrics, blubber depth, n = 21 handlings [15 were unique animals]) and female–pup pairs were weighed (adult females: n = 32 [24]; pups: n = 33 [23]) to validate that UAS 3‐D photogrammetric models provided accurate animal volume and mass estimates. UAS two‐dimensional body length measurements were sensitive to animal recumbency and posture. The new UAS 3‐D photogrammetric method overcame these constraints, and aerial‐derived body volume measurements were equivalent to those collected from the ground. UAS body volume measurements precisely predicted ‘true’ body mass (mean absolute error, adult female: 3.8 kg, 2.1% body mass; pup: 4.1 kg, 9.8%), and exhibited a stronger relationship with total body mass than with blubber volume. The method was applied to 673 free‐living animals to characterize volume and mass dynamics across lactation and breeding for a much larger sample size than would be possible using traditional ground methods. Indeed, 1–46 animals (M ± SE: 9.2 ± 1.2) were modelled concurrently within the focal area of a UAS flight. Application of the method also captured significant inter‐annual variation in body volume/mass dynamics, and female‐to‐pup energy transfer efficiencies were lower when there was low sea ice extent. The UAS 3‐D photogrammetric method presented in this study is likely to be broadly applicable to other species, and the ability to measure whole groups of free‐living animals at once makes strides towards ‘weighing populations’.

Fetal magnetic resonance imaging at 36 weeks predicts neonatal macrosomia: the PREMACRO study

Large-for-gestational-age fetuses are at increased risk of perinatal morbidity and mortality. Magnetic resonance imaging seems to be more accurate than ultrasound in the prediction of macrosomia; however, there is no well-powered study comparing magnetic resonance imaging with ultrasound in routine pregnancies. This study aimed to prospectively compare estimates of fetal weight based on 2-dimensional ultrasound and magnetic resonance imaging with actual birthweights in routine pregnancies. From May 2016 to February 2019, women received counseling at the 36-week clinic. Written informed consent was obtained for this Ethics Committee-approved study. In this prospective, single-center, blinded study, pregnant women with singleton pregnancies between 36 0/7 and 36 6/7 weeks' gestation underwent both standard evaluation of estimated fetal weight with ultrasound according to Hadlock etal and magnetic resonance imaging according to the formula developed by Baker etal, based on the measurement of the fetal body volume. Participants and clinicians were aware of the results of the ultrasound but blinded to the magnetic resonance imaging estimates. Birthweight percentile was considered as the gold standard for the ultrasound and magnetic resonance imaging-derived percentiles. The primary outcome was the area under the receiver operating characteristic curve for the prediction of large-for-gestation-age neonates with birthweights of ≥95th percentile. Secondary outcomes included the comparative prediction of large-for-gestation-age neonates with birthweights of ≥90th, 97th, and 99th percentiles and small-for-gestational-age neonates with birthweights of ≤10th, 5th, and 3rd percentiles for gestational age and maternal and perinatal complications. Of 2914 women who were initially approached, results from 2378 were available for analysis. Total fetal body volume measurements were possible for all fetuses, and the time required to perform the planimetric measurements by magnetic resonance imaging was 3.0 minutes (range, 1.3-5.6). The area under the receiver operating characteristic curve for the prediction of a birthweight of ≥95th percentile was 0.985 using prenatal magnetic resonance imaging and 0.900 using ultrasound (difference=0.085, P<.001; standard error, 0.020). For a fixed false-positive rate of 5%, magnetic resonance imaging for the estimation of fetal weight detected 80.0% (71.1-87.2) of birthweight of ≥95th percentile, whereas ultrasound for the estimation of fetal weight detected 59.1% (49.0-68.5) of birthweight of ≥95th percentile. The positive predictive value was 42.6% (37.8-47.7) for the estimation of fetal weight using magnetic resonance imaging and 35.4% (30.1-41.1) for the estimation of fetal weight using ultrasound, and the negative predictive value was 99.0% (98.6-99.3) for the estimation of fetal weight using magnetic resonance imaging and 98.0% (97.6-98.4) for the estimation of fetal weight using ultrasound. For a fixed false-positive rate of 10%, magnetic resonance imaging for the estimation of fetal weight detected 92.4% (85.5-96.7) of birthweight of ≥95th percentile, whereas ultrasound for the estimation of fetal weight detected 76.2% (66.9-84.0) of birthweight of ≥95th percentile. The positive predictive value was 29.9% (27.2-32.8) for the estimation of fetal weight using magnetic resonance imaging and 26.2% (23.2-29.4) for the estimation of fetal weight using ultrasound, and the negative predictive value was 99.6 (99.2-99.8) for the estimation of fetal weight using magnetic resonance imaging and 98.8 (98.4-99.2) for the estimation of fetal weight using ultrasound. The area under the receiver operating characteristic curves for the prediction of large-for-gestational-age neonates with birthweights of ≥90th, 97th, and 99th percentiles and small-for-gestational-age neonates with birthweights of ≤10th, 5th, and 3rd percentiles was significantly larger in prenatal magnetic resonance imaging than in ultrasound (P<.05 for all). At 36 weeks' gestation, magnetic resonance imaging for the estimation of fetal weight performed significantly better than ultrasound for the estimation of fetal weight in the prediction of large-for-gestational-age neonates with birthweights of ≥95th percentile for gestational age and all other recognized cutoffs for large-for-gestational-age and small-for-gestational-age neonates (P<.05 for all).

Digital anthropometric volumes: Toward the development and validation of a universal software.

Anthropometry is a method for quantifying body size and shape often used to derive body composition and health risk prediction models. Recent technology advancements led to development of three-dimensional (3D) optical scanners that can overcome most of the limitations associated with manual anthropometric data collection. However, each of the currently available devices offers proprietary measurements that do not match conventional anthropometric definitions. The aim of the current study was to develop and then evaluate the precision and accuracy of new "universal" 3D optical analysis software that calculates digital anthropometric volumes using identical standard landmarks across scanners. Dual-energy x-ray absorptiometry (DXA) and air displacement plethysmography (ADP) total body and regional volume and fat mass reference measurements and 3D optical scans from two proprietary devices were collected from 356 participants to evaluate the robustness of total body and regional volume and fat mass measurements calculated by the developed software. Linear regression modeling with threefold cross validation was used to evaluate total body and regional fat masses from 3D scans. Total body and regional volumes measured by DXA and ADP had strong associations with corresponding estimates from the commercial 3D optical scanners coupled with the universal software (e.g., R2 =0.98 for Styku and R2 =1.00 for SS20, for both DXA and ADP comparisons). Regional body volumes also had strong correlation between DXA and the 3DO scanners (e.g., for arm, leg and trunk, respective R2 s of 0.75, 0.86, and 0.97 for Styku and 0.79, 0.89, and 0.98 for SS20). Similarly, there were strong associations between DXA- measured total body and regional fat mass and 3D optical estimates calculated by the universal software (e.g., for total body, arm, leg and trunk, respective R2 s of 0.86, 0.72, 0.77, and 0.88 for Styku and 0.84, 0.76, 0.78, and 0.85 for SS20). Absolute differences in volumes and fat mass between the reference methods and the universal software values revealed underlying proprietary scanner differences that can be improved when designing future devices. The current study suggests that, when compared against values calculated using DXA and ADP, the universal software was able to measure total and regional body volumes reliably from scans obtained by two different scanners. The universal software, with future refinements, combined with potential optical scanner design improvements, creates new opportunities for developing large multicenter anthropometric databases with uniformly defined body dimensions that can be used for modeling health risks. Shape Up! Adults Study, NCT0363785.

Effects of Body Hair on College-Age Males on Body Composition Measurements by BOD POD

Body composition measurements by BOD POD account for the effects of trapped isothermal air in hair on the scalp by having the subject wear a swim cap to compress the hair on the head. However, there are no recommendations that account for the effects of trapped isothermal air in hair elsewhere on the body. The purpose of this investigation was to examine the effect of body hair on body composition measurements by BOD POD. To assess the impact of body hair on body composition measurements, BOD POD measurements were performed in two conditions: wearing single layer compression shorts (CS) apparel with a swim cap (recommended by manufacturer) and wearing single layer limb length compression (LC) apparel with the same swim cap. The order of apparel was conducted in random order to avoid any potential order effect. Fifty male college-age males (age 19.96 ± 1.32 years) volunteered to participate in this study. Body density and percent body fat were calculated from BOD POD measurements of body mass and body volume. Wearing single layer limb length compression apparel to compress body hair increased body mass by an average of 0.67 lb. (±0.05). Compared to wearing only compression shorts, covering exposed body hair resulted in a reduction in body volume measures; thus, body density was calculated as higher in the LC apparel condition. The mean percentage of body fat in the LC condition (13.99 ± 6.64%) was significantly lower than the mean percentage of body fat in the CS condition (16.76 ± 6.27%, p < 0.001). The results of this investigation demonstrate that covering exposed body hair by wearing single layer limb-length compression apparel can result in significantly different measurements of percent body fat in college-age males. These findings indicate that air displacement plethysmography for males while wearing limb-length compression apparel resulted in a lower assessment of body fat by an average of 2.77 percent. Based on the findings of this investigation, body hair needs to be accounted for when percent body fat is being assessed by BOD POD.

Abstract 16983: Validation of 3D Volume Measurement Technology to Assess Body Fat Content Using Biplane Imaging From Mobile Devices

Introduction: Body fat (BF) content better predicts adiposity-related cardiovascular risk than the body mass index (BMI). Accurate and accepted methods to assess BF are complex, expensive, and accessible only in clinical settings. Multi-sensor 3D body volume (3D-BV) measurement technology has been shown to accurately estimate BF. We assessed the hypothesis that 3D models generated from biplane imaging (i.e., front and side facing photographs) using mobile devices (App), could be used to predict body volume measurements and derive BF. Methods: We prospectively enrolled 196 subjects, who underwent 3D-BV (gold standard for body volume) within 24 hours, dual-energy X-ray Absorptiometry (iDEXA) (gold standard for BF) and photographs taken with an Ipad® App at a predefined distance and pose. These photos were post-processed with a computer-assisted algorithm to estimate body length, girth, and volume. These were used to calculate body density (BD) using the bicompartmental principles of body composition (BD=Body Mass/Volume) and derive BF% using the Siri equation [(4.95/BD-4.50) X 100]. Correlation indexes and residual plots were created to compare 3D-BV and iDEXA with the App. Mean differences were compared using a paired t-test. Results: Mean ±SD age was 31.9±9.15 years, 53% were women, weight 72.8±14.1 kg, BMI was 25.5±4.5 kg/m 2 .The App volume correlated with 3D-BV (R 2 =0.95,95%CI 0.90,0.95, p&lt;.0001, Figure 1-A ) ; average difference between App volume vs 3D-BV volume was -1.2 Liters, 95%CI,0.03, 2.42, p=0.06, ( Figure 1-B ). App BF% correlated with iDEXA BF% (R 2 =0.92, 95%CI 0.90,0.94, p&lt;.0001, Figure 1-C ) ; while average difference between App BF% vs iDEXA BF% was -0.13 %, 95%CI -0.6,0.4, p=0.6, ( Figure 1-D ). Conclusion: BF can be estimated using volume measurements obtained by biplane imaging from mobile devices and could serve as a home-based, portable, scalable, cost-effective, and convenient measure to assess BF and track changes in body composition over time.

P1249SEVERE HEMODYNAMIC INSTABILITY DURING DIALYSIS - DRY, STUNNED OR ALLERGIC? STATE OF THE ART ECHOCARDIOGRAPHY COMBINED WITH SIMULTANEOUS LUNG ULTRASOUND

Abstract Background and Aims Intradialytic hypotension is a fairly common and serious adverse phenomenon. Associated comorbidities include e.g. heart failure, hypovolemia, allergic reactions with the dialysis apparatus and electrolyte disturbancies. Excessive ultrafiltration may explain later onset hypotension, but early-onset hemodynamic collapse remains poorly understood. Preventive interventions may include incremental dialysis, increasing dry weight, increasing dialysis time and changing dialysis membranes/apparatus. This study combines Echocardiography (Echo) and Lung Ultrasound (LUS) for hemodynamic phenotyping of patients with severe, early onset intra-dialytic hypotension. The aim is to figure out possible preventive strategies depending on underlying abnormalities. Method We enrolled dialysis patients with a symptomatic decrease in systolic arterial pressure &amp;lt; 90 mmHg requiring norepinephrine during the first 60 minutes of at least two consecutive dialysis sessions in our dialysis department. Echo + LUS was done simultaneously to everyone at baseline, i.e. BEFORE dialysis begun, and later at onset of a hypotension episode during dialysis. Patients with active bleeding or any other obvious temporary etiology for hypotension were excluded. Echo concentrated especially on volemic state and filling pressures, while LUS evaluated the lungs and pleurae for signs of pulmonary congestion. Cardiac structure and function (e.g. valves, ejection fraction) was also evaluated. Results Between 1.10.2019 - 31.12.2019 10 patients were enrolled. All patients eventually required norepinephrine despite fluid challenge. No patients had signs or symptoms of an allergic reaction, such as urticaria or stridor/obstructive respiration, nor significant electrolyte disturbancies. 5/10 patients had severe systolic cardiac dysfunction at baseline (LVEF &amp;lt; 30 %) and these 5 patients also simultaneously showed signs of congestion and fluid overload on ultrasound. On the contrary, the other 5/10 patients without severe cardiac failure all had low left-sided filling pressures and a collapsed inferior vena cava on Echo ALREADY at baseline, i.e. before initiation of dialysis. All of these hypovolemic patients had an excellent residual diuresis (&amp;gt; 1500ml/d). All 10 patients in this study showed a significant drop in body volume measurement (BVM) -curves and left-sided filling pressures on Echo prior to onset of hypotension. Of the 5 patients with severe cardiac dysfunction, 2/5 were transmitted into palliative care without dialysis, while 3/5 could be managed without future norepinephrine by longer, more frequent dialysis sessions using more convective and less diffusive dialysis. Of the latter 5 “dry” patients without severe cardiac dysfunction, 3/5 had no more hypotensive episodes after increasing dry weight and using incremental dialysis programs, and the remaining 2 dry patients could be completely switched off dialysis due to vivid residual function. 3/5 of the “dry patients” had a baseline pulse pressure &amp;gt; 120 mmHg and 3 had coronary artery disease, both possibly predisposing to diastolic under-filling. No patients in this study presented with significant myocardial stunning, defined as a &amp;gt; 10 % decrease in LVEF compared to baseline. Conclusion Severe, intra-dialytic hypotension requiring vasopressors may be prevented by individual tailoring of dialysis prescription. Ultrasound may help phenotyping patients requiring different dialysis strategies, including stopping dialysis entirely. Stunning and allergic reactions seemed rare. At baseline, patients seemed to be mainly 1) either over-dialyzed (hypovolemic or hypo-osmotic) or 2) having significant cardiac disease, naturally requiring quite opposite preventive strategies. A decrease in left ventricular preload furthermore occurred in all patients at onset of hypotension, suggesting crossover of a patient-specific preload threshold.

3 Dimensional photonic scans for measuring body volume and muscle mass in the standing horse.

Reasons for performing studyAlthough muscle mass strongly influences performance, there is currently no effective means to measure the 3-dimensional muscle mass of horses. We evaluated a 3-dimensional (3D) scanning methodology for its ability to quantify torso and hindquarter volumes as a proxy for regional muscle mass in horses.ObjectivesDetermine the repeatability of 3D scanning volume (V) measurements and their correlation to body weight, estimated body volume and muscle/fat ultrasound (US) depth.MethodsHandheld 3D photonic scans were performed on 16 Quarter Horses of known body weight 56 days apart (n = 32 scans) with each scan performed in duplicate (n = 32 replicates). Tail head fat, gluteal and longissimus dorsi muscle depths were measured using US. Processed scans were cropped to isolate hindquarter (above hock, caudal to tuber coxae) and torso (hindquarter plus dorsal thoracolumbar region) segments and algorithms used to calculate V. Torso and hindquarter volume were correlated with body weight and US using Pearson’s correlation and with estimated torso volume (50% body weight / body density) with Bland-Altman analysis.ResultsScans took 2 min with < 3.5% error for duplicate scans. Torso volume (R = 0.90, P< 0.001) and hindquarter volume (R = 0.82, P< 0.001) strongly correlated with body weight and estimated BV (R = 0.91) with low bias. Torso volume moderately correlated to mean muscle US depth (R = 0.4, P< 0.05) and tail head fat (R = 0.42, P< 0.01). Mean muscle US depth moderately correlated to body weight (R = 0.50, P< 0.01).Main limitations3D Scans determine body volume not muscle volume.ConclusionsThe hand-held 3D scan provided a rapid repeatable assessment of torso and hindquarter volume strongly correlated to body weight and estimated volume. Superimposition of regional scans and volume measures could provide a practical means to follow muscle development when tail head fat depth remain constant.

In Vivo Measurements of Lung Volumes in Ringed Seals: Insights from Biomedical Imaging.

Marine mammals rely on oxygen stored in blood, muscle, and lungs to support breath-hold diving and foraging at sea. Here, we used biomedical imaging to examine lung oxygen stores and other key respiratory parameters in living ringed seals (Pusa hispida). Three-dimensional models created from computed tomography (CT) images were used to quantify total lung capacity (TLC), respiratory dead space, minimum air volume, and total body volume to improve assessments of lung oxygen storage capacity, scaling relationships, and buoyant force estimates. Results suggest that lung oxygen stores determined in vivo are smaller than those derived from postmortem measurements. We also demonstrate that-while established allometric relationships hold well for most pinnipeds-these relationships consistently overestimate TLC for the smallest phocid seal. Finally, measures of total body volume reveal differences in body density and net vertical forces in the water column that influence costs associated with diving and foraging in free-ranging seals.

Test\u2013retest repeatability of the NX-16: a three-dimensional (3D) body scanner in a male cohort

PurposeWhole-body three-dimensional scanning is a tool utilised for the collection of body girths, volume, and surface area measurements. Few studies have investigated the validity and repeatability of this technology. The aim of the present study was to investigate the test retest variability of the NX-16 body scanner (NX-16, TC2, Cary, North Carolina, USA).MethodsPhase one involved the measurement of a mannequin on 300 occasions (30 scans over 10 sessions). In phase two, 13 apparently healthy male participants were recruited; each participant was scanned a total of four times (two scans over two sessions). Stature, body mass, and body fat % were obtained. Fourteen girth measurements were obtained (chest, underbust, stomach, waist, seat, hip, R/L bicep, R/L thigh, R/L mid-thigh, and R/L calf). Coefficient of variation was calculated for measurements obtained.ResultsCoefficient of variation for phase one ranged from 0.0% for the R calf, to 3.3% for the L thigh measurement. For phase two, values were higher, ranging from 0.5% for calf and chest to 4.6% for thigh measurements.ConclusionsTest–retest variability of the measurements provided by the NX-16 body scanner varied according to body location. However, variability within measurements was low using a mannequin or human participant. The NX-16 body scanner (TC2, Cary, North Carolina, USA) may be a useful tool for tracking changes in body composition over time during large population studies.

Utilizing Free Augmented Reality App for Learning Geometry at Elementary School in Taiwan

From random interviews of mathematics teachers, the researchers are conscious that students have difficulties in solving problems regarding compound body volume measurement. The researchers found the main factor involved in the difficulties was incomplete spatial concepts. Augmented reality (AR), which is a kind of educational technology, has been widely applied in the educational field in recent years. AR provides two- or three-dimensional objects and/or information and interaction with them. These characteristics can compensate for the insufficient characterization of compound-body volume in traditional education environments. The paper studies evaluation in utilizing free augmented reality to learn volumetric measurement of compound bodies to complete spatial concepts as well as improve the students' learning performance. The finding suggests that the positive impact on visualization and interaction as well as attitude lead students to be more engaged in learning activities with less cognitive effort, resulting in better learning performance.