Faunal colonization of artificial seagrass plots: The importance of surface area versus space size relative to body size

Estuaries ◽  
2002 ◽  
Vol 25 (5) ◽  
pp. 1045-1052 ◽  
Author(s):  
Aaron Bartholomew
Keyword(s):  
Body Size ◽  
Surface Area ◽  
Space Size

Theoretical and empirical scaling patterns and topological homology in bone trabeculae.

1998 ◽  
Vol 201 (4) ◽  
pp. 573-590
Author(s):  
S M Swartz ◽  
A Parker ◽  
C Huo
Keyword(s):  
Body Size ◽  
Surface Area ◽  
Cancellous Bone ◽  
Structural Design ◽  
Theoretical Models ◽  
Small Animals ◽  
Bone Trabeculae ◽  
Large Animals ◽  
Vertebrate Skeleton ◽  
Area And Volume

Trabecular or cancellous bone is a major element in the structural design of the vertebrate skeleton, but has received little attention from the perspective of the biology of scale. In this study, we investigated scaling patterns in the discrete bony elements of cancellous bone. First, we constructed two theoretical models, representative of the two extremes of realistic patterns of trabecular size changes associated with body size changes. In one, constant trabecular size (CTS), increases in cancellous bone volume with size arise through the addition of new elements of constant size. In the other model, constant trabecular geometry (CTG), the size of trabeculae increases isometrically. These models produce fundamentally different patterns of surface area and volume scaling. We then compared the models with empirical observations of scaling of trabecular dimensions in mammals ranging in mass from 4 to 40x10(6)g. Trabecular size showed little dependence on body size, approaching one of our theoretical models (CTS). This result suggests that some elements of trabecular architecture may be driven by the requirements of maintaining adequate surface area for calcium homeostasis. Additionally, we found two key consequences of this strongly negative allometry. First, the connectivity among trabecular elements is qualitatively different for small versus large animals; trabeculae connect primarily to cortical bone in very small animals and primarily to other trabeculae in larger animals. Second, small animals have very few trabeculae and, as a consequence, we were able to identify particular elements with a consistent position across individuals and, for some elements, across species. Finally, in order to infer the possible influence of gross differences in mechanical loading on trabecular size, we sampled trabecular dimensions extensively within Chiroptera and compared their trabecular dimensions with those of non-volant mammals. We found no systematic differences in trabecular size or scaling patterns related to locomotor mode.

Body size, not age, predicts parasite load in Clark’s Spiny Lizards (Sceloporus clarkii)

2019 ◽  
Vol 97 (3) ◽  
pp. 220-224 ◽  
Author(s):  
H.V. Watkins ◽  
G. Blouin-Demers
Keyword(s):  
Body Size ◽  
Surface Area ◽  
Intraspecific Variation ◽  
Wild Population ◽  
Parasite Load ◽  
Older Individuals ◽  
Fundamental Goal ◽  
Males And Females ◽  
Ectoparasite Load

Determining the factors that influence parasite load is a fundamental goal of parasitology. Body size often influences parasite load in reptiles, but it is unclear whether higher levels of parasitism are a result of greater surface area of individuals (a function of size) or of longer periods of exposure to parasites (a function of age). Using skeletochronology in a wild population of Clark’s Spiny Lizards (Sceloporus clarkii Baird and Girard, 1852), we tested the hypotheses that (i) larger individuals have higher parasite loads due to increased surface area available for colonization by parasites and their vectors and that (ii) older individuals have higher parasite loads because they have had longer exposure to parasites and their vectors. Males harboured more ectoparasites than females. Males and females differed in how body size influenced chigger (Acari: Trombiculidae) load; larger males harboured more chiggers than smaller males, but this was not the case in females. Age did not affect ectoparasite load in either sex. These results emphasize the importance of disentangling the effects of size and age in models of parasitism to gain a clearer understanding of intraspecific variation in parasite load.

III. PULMONARY DIFFUSION

PEDIATRICS ◽  
1965 ◽  
Vol 35 (1) ◽  
pp. 185-193
Author(s):  
George R. DeMuth ◽  
William F. Howatt
Keyword(s):  
Carbon Monoxide ◽  
Body Size ◽  
Longitudinal Data ◽  
Surface Area ◽  
Residual Variance ◽  
Normal Variation ◽  
Diffusing Capacity ◽  
Healthy Individuals ◽  
Lung Volumes ◽  
Mean Values

1. Equations describing the normal variation and changes with size of the diffusing capacity (rebreathing technique) for boys and girls have been obtained from 230 observations on 139 children. 2. The use of covariance analysis on the longitudinal data reduces the residual variance by about half, indicating that in children the diffusing capacity for carbon monoxide, Dco, grows along growth lines. This aids in finding significant deviations from the predicted in children who are followed with repeated examinations. 3. The Dco increases with growth in a manner very similar to that of the lung volumes, not only in respect to height, but also in respect to age, weight, and surface area. The ratio Dco/TLC expresses a relationship which does not vary with body size, age, or sex in these healthy individuals. Although boys and girls have the same mean values, the correlation between each individual's values from the two series is significant for boys but not for girls. 4. The constancy of the Dco/TLC during growth supports the hypothesis that the lung grows between the ages of 5 and 18 years by the addition of new air spaces rather than by enlarging the pre-existing ones.

scholarly journals Increased mortality in women: sex differences in burn outcomes

2017 ◽  
Vol 5 ◽  
Author(s):  
Karen Karimi ◽  
Iris Faraklas ◽  
Giavonni Lewis ◽  
Daniel Ha ◽  
Bridget Walker ◽  
...  
Keyword(s):  
Sex Differences ◽  
Body Size ◽  
Surface Area ◽  
Body Surface Area ◽  
Body Surface ◽  
Thermal Injury ◽  
Inhalation Injury ◽  
Inpatient Mortality ◽  
Burn Centers ◽  
Significant Difference

Abstract Background There is increasing evidence that sex differences may influence responses after thermal injury and affect clinical outcomes. The objective of this study was to evaluate the relationships between sex, thermal injury, body size, and inpatient mortality in burn patients. Methods Medical records of adults with >20% total body surface area (TBSA) burn injury admitted to two American Burn Association (ABA)-verified burn centers between 2008 and 2014 were retrospectively reviewed. Injury details and baseline characteristics, including body size as estimated by body surface area (BSA) and body mass index (BMI) were recorded, along with details of the hospital course. The primary outcome of inpatient mortality was compared between sexes. Results Out of 334 subjects, 60 were women (18%). Median TBSA was 33% (IQR 25–49) in this cohort, with 19% full thickness burns and 30% inhalation injury. Despite no significant difference in age, presence of inhalation injury, TBSA, or depth of burn, women had significantly higher rates of inpatient mortality (45 vs. 29%, P = 0.01). BSA was significantly lower in women vs. men (P < 0.001), but this difference was not more pronounced among non-survivors. There was no difference in BMI between men and women non-survivors. Although not significant (P = 0.28), women succumbed to their injuries sooner than men (day 4 vs. 10 post-injury). Conclusions Women are less likely to survive burn injuries and die sooner than men with similar injuries. Body size does not appear to modulate this effect. Burn centers should be aware of the higher mortality risk in women with large burns.

Kidney Size and Body Size in the Context of Salt and Blood Pressure

1982 ◽  
Vol 63 (s8) ◽  
pp. 419s-421s
Author(s):  
F. O. Simpson ◽  
R. Doesburg ◽  
A. G. Dempster ◽  
M. Kihara ◽  
Y. Yamori ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Body Mass Index ◽  
Body Size ◽  
Surface Area ◽  
Body Surface ◽  
Sodium Intake ◽  
Kidney Weight ◽  
Kidney Size ◽  
European Origin ◽  
New Zealanders

1. Kidney weight was analysed for Japanese and New Zealanders of European origin who had died sudden deaths. 2. Kidney weight was relatively greater in Japanese than in New Zealanders. 3. Kidney weight was closely related to body surface area and weight and less closely to height and body mass index. 4. As kidney function is related to kidney size and thus in turn to body size it is advisable to take account of body size in analyses of sodium intake and excretion in relation to blood pressure.

Relation of Body Size and Surface Area to Gas Exchange in Anurans

1968 ◽  
Vol 41 (1) ◽  
pp. 65-85 ◽  
Author(s):  
Victor H. Hutchison ◽  
Walter G. Whitford ◽  
Margaret Kohl
Keyword(s):  
Body Size ◽  
Gas Exchange ◽  
Surface Area

Body size distribution in aphids: relative surface area of specific plant structures

1995 ◽  
Vol 20 (2) ◽  
pp. 111-117 ◽  
Author(s):  
A. F. G. DIXON ◽  
P. KINDLMANN ◽  
V. JAROŠIK
Keyword(s):  
Body Size ◽  
Size Distribution ◽  
Surface Area

Influence of body size on oxygen consumption during bicycling

1987 ◽  
Vol 62 (2) ◽  
pp. 668-672 ◽  
Author(s):  
D. P. Swain ◽  
J. R. Coast ◽  
P. S. Clifford ◽  
M. C. Milliken ◽  
J. Stray-Gundersen
Keyword(s):  
Body Weight ◽  
Oxygen Consumption ◽  
Body Size ◽  
Surface Area ◽  
Frontal Area ◽  
Distinct Advantage ◽  
O2 Consumption ◽  
Air Resistance ◽  
All Speeds

Energy in bicycling is primarily expended to overcome air resistance, which is proportional to a cyclist's surface area (SA). Thus we hypothesized that large cyclists should have a lower O2 consumption normalized to body weight (VO2/BW) than small cyclists because of the former's lower SA/BW. We measured the VO2/BW of small (BW = 59.4 +/- 4.1 kg) and large (BW = 84.4 +/- 3.2 kg) cyclists while they bicycled on a flat road at 10, 15, and 20 mph. The large cyclists had a 22% lower VO2/BW than the small cyclists at all speeds. However, the SA/BW ratio of the large cyclists was only 11% lower than that of the small cyclists. We then photographically determined the frontal area (FA) of the cyclists in a racing posture, and found that the large cyclists had a 16% lower FA/BW ratio than the small cyclists. We conclude that large cyclists are at a distinct advantage, in terms of VO2/BW, while bicycling on level roads, and this advantage is principally due to their lower FA/BW ratio.

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