scholarly journals The Effect of Obesity Class on the Energetics and Mechanics of Walking

Nutrients ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 4546
Author(s):  
Julia Primavesi ◽  
Aitor Fernández Menéndez ◽  
Didier Hans ◽  
Lucie Favre ◽  
Fabienne Crettaz von Roten ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Energy Cost ◽  
Principal Component ◽  
Normal Weight ◽  
Net Energy ◽  
Obesity Class ◽  
Significant Difference ◽  
Severely Obese ◽  
Gait Mechanics ◽  
Energy Cost Of Walking

Higher mass-normalized net energy cost of walking (NetCw/kg) and mechanical pendular recovery are observed in obese compared to lean adults. This study aimed to investigate the effect of different classes of obesity on the energetics and mechanics of walking and to explore the relationships between body mass, NetCw/kg and gait mechanics by using principal component analysis (PCA). NetCw/kg and gait mechanics were computed in severely obese (SOG; n = 18, BMI = 40.1 ± 4.4 kg·m−2), moderately obese (MOG; n = 17, BMI = 32.2 ± 1.5 kg·m−2) and normal-weight (NWG; n = 13, BMI = 22.0 ± 1.5 kg·m−2) adults during five walking trials (0.56, 0.83, 1.11, 1.39, 1.67 m·s−1) on an instrumented treadmill. NetCw/kg was significantly higher in SOG compared to NWG (p = 0.019), with no significant difference between SOG and MOG (p = 0.14), nor between MOG and NWG (p = 0.27). Recovery was significantly higher in SOG than in NWG (p = 0.028), with no significant difference between SOG and MOG (p = 0.13), nor between MOG and NWG (p = 0.35). PCA models explained between 17.0% and 44.2% of the data variance. This study showed that: (1) obesity class influences the gait energetics and mechanics; (2) PCA was able to identify two components, showing that the obesity class is associated with lower walking efficiency and better pendulum-like characteristics.

scholarly journals Leaf geometric morphometrics among populations of Dalbergia ecastaphyllum (L.) Taub.

2019 ◽  
Vol 35 (6) ◽  
Author(s):  
Daniel Vieira de Morais ◽  
Lorena Andrade Nunes ◽  
Vandira Pereira da Mata ◽  
Maria Angélica Pereira de Carvalho Costa ◽  
Geni da Silva Sodré ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Geometric Morphometrics ◽  
Cross Validation ◽  
Abiotic Factors ◽  
Principal Component ◽  
Canonical Variate ◽  
Validation Test ◽  
Significant Difference ◽  
Variate Analysis ◽  
Geographical Distances

Leaves are plant structures that express important traits of the environment where they live. Leaf description has allowed identification of plant species as well as investigation of abiotic factors effects on their development, such as gases, light, temperature, and herbivory. This study described populations of Dalbergia ecastaphyllum through leaf geometric morphometrics in Brazil. We evaluated 200 leaves from four populations. The principal component analysis (PCA) showed that the first four principal components were responsible for 97.81% of variation. The non-parametric multivariate analysis of variance (NPMANOVA) indicated significant difference between samples (p = 0.0001). The Mentel test showed no correlation between geographical distances and shape. The canonical variate analysis (CVA) indicated that the first two variables were responsible for 96.77 % of total variation, while the cross-validation test showed an average of 83.33%. D. ecastaphyllum leaves are elliptical and ovate.

scholarly journals IM-03 IMMUNOLOGICAL SUBTYPES OF GLIOBLASTOMA BASED ON TUMOR INFILTRATING CELLS

2019 ◽  
Vol 1 (Supplement_2) ◽  
pp. ii12-ii12
Author(s):  
Kushihara Yoshihiro ◽  
Syota Tanaka ◽  
Erika Yamasawa ◽  
Tsukasa Koike ◽  
Taijun Hana ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
T Cell ◽  
Tumor Microenvironment ◽  
Nk Cells ◽  
Principal Component ◽  
Component Analysis ◽  
Gene Set ◽  
Significant Difference

Abstract To discover novel biological targets in glioblastoma, genomic and immunological analysis were performed using The Cancer Genome Atlas (TCGA) data set. The RNA-seq data of 156 primary glioblastoma cases were subjected to CIBERSORT to detect tumor infiltrating cell fractions. Principal component analysis was performed on this data to detect factors that strongly contribute to the first principal component, and hierarchical clustering was performed. Survival curves were compared for each of the derived clusters. Finally, Gene Set Enrichment Analysis (GSEA) using HALLMARK Gene Set was performed. In the principal component analysis, we detected seven factors (NK cells resting, T cell regulatory, NK cells activated, Macrophage type 0, T cell gamma delta, Macrophage type 2, Macrophage type 1) which strongly contribute to the first principal component. Based on these seven factors, hierarchical cluster analysis resulted in T cell regulatory (Treg), Macrophage type 0 (M0), Macrophage type 2 (M2) and Macrophage type 1 (M1) clusters. There was no significant difference between these groups in CD8 T cell. M2 and M1 clusters displayed better OS with a significant difference. TNFA signaling via NFκB in Treg group, IFNα response, IFNγ response and ALLOGRAFT response in M2 group, G2M CHECKPOINT, GLYCOLYSIS, WNTβ catenin signaling, MITOTIC SPINDLE and TGFβ signaling in M1 group were upregulated. In conclusion, tumor microenvironment of glioblastoma can be divided into 4 immunological subtypes, Treg, M0, M1, and M2. Because of the contribution of innate immunity for shaping the tumor microenvironment of glioblastoma, immunotherapies targeting these innate immune cells are anticipated.

scholarly journals Severe obesity in children as an independent risk factor for perioperative respiratory adverse events during anaesthesia for minor non-airway surgery, a retrospective observational study

2018 ◽  
Vol 28 (2) ◽  
pp. 83-89
Author(s):  
Kavitha Raghavan ◽  
Daphne Xin Ying Moo ◽  
Zihui Tan
Keyword(s):  
Adverse Events ◽  
Fold Increase ◽  
Normal Weight ◽  
Obese Children ◽  
Medical Comorbidities ◽  
Airway Surgery ◽  
Respiratory Airway ◽  
Obstructive Sleep ◽  
Significant Difference ◽  
Severely Obese

Purpose: The purpose of this article is to quantify grades of obesity and their independent effects on perioperative adverse events in children having ambulatory minor non-airway surgery. Methods: After obtaining ethics committee approval, we selected every tenth child aged 2 to 16 years who was identified as having been a day case between January 2012 and December 2014. Weight groups were defined based on age- and gender-specific body mass index (BMI) cutoff points. A sample size of 1102 was calculated to demonstrate a three-fold increase in the primary outcome measure, perioperative respiratory-airway adverse events, among obese children, with a power of 80% and an alpha error of 5%. Chi-squared and Fisher exact tests were used to compare proportions, and independent sample t tests were used to compare means. Results: Severely obese children had a significantly higher incidence of perioperative respiratory-airway adverse events when compared to normal-weight children despite no difference in respiratory and other comorbidity. Obese children had higher prevalence of overall medical comorbidities and obstructive sleep apnoea when compared to normal-weight children and there was no significant difference in the incidence of perioperative respiratory-airway adverse events and other outcome measures between obese and normal-weight children. Conclusions and recommendations: Severely obese children have a higher risk of perioperative respiratory-airway adverse events even during minor non-airway surgery despite absence of medical comorbidities. We recommend the use of age- and sex- specific BMI cutoffs or BMI percentile charts to identify children who are severely obese to anticipate and prevent major respiratory adverse events.

scholarly journals Cycling efficiency and energy cost of walking in young and older adults

2018 ◽  
Vol 124 (2) ◽  
pp. 414-420 ◽  
Author(s):  
Glenn A. Gaesser ◽  
Wesley J. Tucker ◽  
Brandon J. Sawyer ◽  
Dharini M. Bhammar ◽  
Siddhartha S. Angadi
Keyword(s):  
Older Adults ◽  
Individual Variation ◽  
Energy Cost ◽  
Intraclass Correlation ◽  
Age Groups ◽  
Net Energy ◽  
Age Group ◽  
Cycling Efficiency ◽  
Considerable Individual Variation ◽  
Energy Cost Of Walking

To determine whether age affects cycling efficiency and the energy cost of walking (Cw), 190 healthy adults, ages 18–81 yr, cycled on an ergometer at 50 W and walked on a treadmill at 1.34 m/s. Ventilation and gas exchange at rest and during exercise were used to calculate net Cw and net efficiency of cycling. Compared with the 18–40 yr age group (2.17 ± 0.33 J·kg−1·m−1), net Cw was not different in the 60–64 yr (2.20 ± 0.40 J·kg−1·m−1) and 65–69 yr (2.20 ± 0.28 J·kg−1·m−1) age groups, but was significantly ( P < 0.03) higher in the ≥70 yr (2.37 ± 0.33 J·kg−1·m−1) age group. For subjects >60 yr, net Cw was significantly correlated with age ( R2 = 0.123; P = 0.002). Cycling net efficiency was not different between 18–40 yr (23.5 ± 2.9%), 60–64 yr (24.5 ± 3.6%), 65–69 yr (23.3 ± 3.6%) and ≥70 yr (24.7 ± 2.7%) age groups. Repeat tests on a subset of subjects (walking, n = 43; cycling, n = 37) demonstrated high test-retest reliability [intraclass correlation coefficients (ICC), 0.74–0.86] for all energy outcome measures except cycling net energy expenditure (ICC = 0.54) and net efficiency (ICC = 0.50). Coefficients of variation for all variables ranged from 3.1 to 7.7%. Considerable individual variation in Cw and efficiency was evident, with a ~2-fold difference between the least and most economical/efficient subjects. We conclude that, between 18 and 81 yr, net Cw was only higher for ages ≥70 yr, and that cycling net efficiency was not different across age groups. NEW & NOTEWORTHY This study illustrates that the higher energy cost of walking in older adults is only evident for ages ≥70 yr. For older adults ages 60–69 yr, the energy cost of walking is similar to that of young adults. Cycling efficiency, by contrast, is not different across age groups. Considerable individual variation (∼2-fold) in cycling efficiency and energy cost of walking is observed in young and older adults.

Silvering of European eel (Anguilla anguilla L.): seasonal changes of morphological and metabolic parameters

2007 ◽  
Vol 57 (1) ◽  
pp. 63-77 ◽  
Author(s):  
S. Paul Balm ◽  
Caroline Durif ◽  
Vincent van Ginneken ◽  
Erik Antonissen ◽  
Ron Boot ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Principal Component ◽  
Anguilla Anguilla ◽  
Component Analysis ◽  
Metabolic Energy ◽  
Hepatosomatic Index ◽  
European Eel ◽  
Silver Eel ◽  
Migratory Activity ◽  
Significant Difference

AbstractThe transformation of yellow eel into silver eel is called 'silvering', and takes place prior to migration. We found the sedentary yellow phase in spring, the migratory silver phase in autumn, while August was a cross-over month. We used principal component analysis (PCA) to characterise the morphological and physiological changes that accompany silvering in the European eel (Anguilla anguilla L.). Silvering is positively related to external parameters such as eye size, internal maturation parameters like GSI, vitellogenine (VIT), and blood-substrates such as phospholipids, Free Fatty Acids (FFA), and cholesterol. The Hepatosomatic Index was not significantly different between yellow and silver groups. In contrast, a significant difference was observed for parameters of body constitution (fat, protein, dry matter) between yellow and silver stages. Furthermore, the process of silvering is accompanied with increased levels of cortisol in autumn, which plays a role in mobilisation of metabolic energy from body stores towards migratory activity and gonadal growth. Based on Principal Component Analysis (PCA) with physiological, morphological and endocrinological parameters, it is concluded that during the process of silvering, several developmental stages can be recognised, with a timeframe of the premigratory sedentary yellow phase from April until July, August is a cross-over month, and the migratory silver phase is found from September until November.

scholarly journals Description of facial symmetry in patients with unilateral cleft lip and palate using geometric morphometry and computerized tomography

2017 ◽  
Vol 22 (1) ◽  
pp. 20-25
Author(s):  
Sthepanie Ruiz ◽  
Anderson Silva ◽  
Mayra Celis ◽  
Rocio Ruales ◽  
Francined Pardo ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Thin Plate ◽  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Principal Component ◽  
Component Analysis ◽  
Small Sample ◽  
Geometric Methods ◽  
Affected Side ◽  
Significant Difference

Objective: To describe the maxillary asymmetry in patients with single cleft lip and palate by using morphometrics geometric methods. Materials and Methods: Applied morphometrics geometric methods to analyze images captured from 3D reconstructions of CT scans of 9 patients with unilateral cleft lip and palate, mean age of 13.7 years was used. Tps Dig2 software was used to digitalize 6 maxillary landmarks shaping both the affected and the sides unaffected. TpsPower and TpsPLS to a small sample for relative warps and consensus for superimposition. Thin plate function and asymmetry was used applying ASI-CLIC® package, and the principal component analysis was performed with the PAST software version 2.17.0. Results: There is a statistically significant difference (p<0.05) between the conformation of the maxilla on the affected side compared to unaffected. The study of asymmetry indicated different degrees and differences in the nature of the asymmetry that characterizes different deformities of unilateral cleft lip and palate. The principal component analysis demonstrates both inter-group variability and recognizes two principal components, 39.4%, to the first component and 27.5% to the second component. There is a high correlation between the formation of the unaffected side and affected side conformation r= 0.93847. The thin plate deformation is uniform. The allometry study indicated that there is no association between the shape and size. Conclusions: Morphometry Geometric method is a useful tool for assessing preoperative maxillary conformations in patients with unilateral cleft lip and palate. The side without the cleft is also affected, and is associated with the formation on the side of the cleft. The frontonasal suture is also affected, in a greater proportion than the fronto zigomatic.

scholarly journals Agronomic Performance and Organoleptic Characteristics of Local Varieties of Sweet Potato (Ipomea batatas) Cultivated in Mbaiki (Central African Republic)

2021 ◽  
pp. 1-11
Author(s):  
Gorgon Igor Touckia ◽  
Lucie Aba-toumnou ◽  
Ephrem Kosh Komba ◽  
Cherubin Dan-zi ◽  
Kouami Kokou
Keyword(s):  
Principal Component Analysis ◽  
Sweet Potato ◽  
Central African Republic ◽  
Principal Component ◽  
Component Analysis ◽  
Growth And Yield ◽  
P Value ◽  
Local Varieties ◽  
Organoleptic Characteristics ◽  
Significant Difference

In the Central African Republic, there are a multitude of local varieties of sweet potato. However, few studies have been carried their agro morphological and organoleptic characteristics. A Fisher random block device was set up on the three local varieties of sweet potato. The growing and production parameters were evaluated as well as the organoleptic characteristics through the food taste test. The parameters of growing and production were assessed by means of analysis of variance (ANOVA) with one classification criterion using the R software version 3.1.3. A Principal Component Analysis (PCA) was also performed with the growth and yield parameters in order to highlight the correlations between these different parameters. The variety 1 (V1) produced the plants with the largest diameters (1.30 cm), while the smallest diameters was observed in the variety 2 (V2) with 0.55 cm. There is a significant difference (P-value = 0.0001) between the different varieties according to the ANOVA test. According to the length of the tuber, the V2 produced the longest tuberous root than the others with an average of 28.53 cm. The smallest length is observed in the V3 with an average of 25.12 cm. There is not significant (p-value = 0.216) in relation with the length of the tuber for the cultivated varieties of the sweet potato. The eigenvalues of the two main axes extracted from the Principal Component Analysis explained 53.68% and 16.82% of the matrix growth/ yield information. Along the factor axes, apart from parameters such as tuber diameters and length which are not positively correlated, there is little variability between the other parameters which are strongly correlated.

scholarly journals Dear Program Director: Deciphering Letters of Recommendation

2018 ◽  
Vol 10 (3) ◽  
pp. 261-266 ◽  
Author(s):  
Kris Saudek ◽  
David Saudek ◽  
Robert Treat ◽  
Peter Bartz ◽  
Rachel Weigert ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Repeated Measures ◽  
Principal Component ◽  
Component Analysis ◽  
Program Director ◽  
Cross Sectional ◽  
Likert Score ◽  
Significant Difference ◽  
Fellowship Programs ◽  
Letters Of Recommendation

ABSTRACT Background  Letters of recommendation (LORs) are an important part of applications for residency and fellowship programs. Despite anecdotal use of a “code” in LORs, research on program director (PD) perceptions of the value of these documents is sparse. Objective  We analyzed PD interpretations of LOR components and discriminated between perceived levels of applicant recommendations. Methods  We conducted a cross-sectional, descriptive study of pediatrics residency and fellowship PDs. We developed a survey asking PDs to rate 3 aspects of LORs: 13 letter features, 10 applicant abilities, and 11 commonly used phrases, using a 5-point Likert scale. The 11 phrases were grouped using principal component analysis. Mean scores of components were analyzed with repeated-measures analysis of variance. Median Likert score differences between groups were analyzed with Mann-Whitney U tests. Results  Our survey had a 43% response rate (468 of 1079). “I give my highest recommendation” was rated the most positive phrase, while “showed improvement” was rated the most negative. Principal component analysis generated 3 groups of phrases with moderate to strong correlation with each other. The mean Likert score for each group from the PD rating was calculated. Positive phrases had a mean (SD) of 4.4 (0.4), neutral phrases 3.4 (0.5), and negative phrases 2.6 (0.6). There was a significant difference among all 3 pairs of mean scores (all P &lt; .001). Conclusions  Commonly used phrases in LORs were interpreted consistently by PDs and influenced their impressions of candidates. Key elements of LORs include distinct phrases depicting different degrees of endorsement.

scholarly journals Energy-saving walking mechanisms in obese adults

2019 ◽  
Vol 126 (5) ◽  
pp. 1250-1258 ◽  
Author(s):  
Aitor Fernández Menéndez ◽  
Mathieu Saubade ◽  
Grégoire P. Millet ◽  
Davide Malatesta
Keyword(s):  
Energy Saving ◽  
Body Mass ◽  
Elastic Energy ◽  
Energy Cost ◽  
Mechanical Energy ◽  
Energy Usage ◽  
Obese Adults ◽  
External Work ◽  
Significant Difference ◽  
Energy Cost Of Walking

Energy-saving mechanisms are used in human walking. In obese adults the energy cost of walking (Cw) is higher compared with normal-body mass adults. However, the biomechanical factors involved in this extra cost should result in a higher Cw. The aim of this study was to compare energy-saving walking mechanisms [i.e., mechanical energy saved via pendulum (Recovery) and maximum possible elastic energy usage (MPEEu)] and their influence on Cw in obese vs. lean individuals. The net Cw (NetCw), external work (Wext), Recovery, MPEEu, and gait weight transfer duration (gWT) were computed for 13 lean [L; body mass index (BMI) 21.9 ± 1.5 kg/m2] and 13 obese (O; BMI 33.8 ± 2.5 kg/m2) individuals during treadmill walking at five speeds (0.56, 0.83, 1.11, 1.39, 1.67 m/s). No significant difference was found between groups in relative (per kg of body mass) NetCw ( P = 0.13). Relative positive Wext was significantly lower at the three fastest speeds ( P ≤ 0.003) whereas Recovery was higher at the two fastest speeds ( P ≤ 0.01) in O than in L individuals. MPEEu tended to be lower in O than in L ( P = 0.06), with significantly lower values in O compared with L at 1.39 and 1.67 m/s ( P ≤ 0.017). gWT was significantly shorter in O than in L individuals at 1.67 m/s ( P = 0.001). The present results reveal that obese adults rely more on the pendular mechanism than on the storage and release of elastic energy for decreasing the amount of positive Wext and thus limiting the increase in the relative NetCw. NEW & NOTEWORTHY We observed that obese individuals had a lower maximum possible elastic energy usage per kilogram of body mass than their lean counterparts and they may rely more on the pendular mechanism of walking than on the storage and release of elastic energy for decreasing the external mechanical work and thus limiting the increase in the relative net energy cost of walking.

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