Surface areas of phocid seals

1990 ◽  
Vol 68 (12) ◽  
pp. 2531-2538 ◽  
Author(s):  
S. Innes ◽  
G. A. J. Worthy ◽  
D. M. Lavigne ◽  
K. Ronald
Keyword(s):  
Surface Area ◽  
Body Mass ◽  
Marine Mammals ◽  
Sea Otter ◽  
Terrestrial Mammals ◽  
Surface Areas ◽  
Two Samples ◽  
Phocid Seals ◽  
The Mean ◽  
The Relationship

Standard morphometries and body surface areas were determined for 56 captive phocid seals. The mean Meeh constant, describing the relationship between maximum surface area (Amax) and body mass raised to the power 2/3 (m0.67), was 0.088 ± 0.011 m2∙kg−0.67. This value was not significantly different (P < 0.05) from the mean Meeh constant for 13 species of marine mammals (0.090 ± 0.018 m2∙kg−0.67), nor was it significantly different from the Meeh constants calculated for two samples of terrestrial mammals (0.097 ± 0.019 (N = 57) and 0.10 ± 0.013 m2∙kg−0.67 (N = 21)). The empirical allometric relationship between body mass and surface area for our phocid seals was log Amax = log 0.14 + 0.51 log m (R2 = 0.84). This relationship was not significantly different from that calculated for cetaceans, but was, however, significantly different from that calculated for terrestrial mammals. On average, surface areas of marine mammals (including pinnipeds, cetaceans, and the sea otter) were 23% smaller for their mass than those of terrestrial mammals.

Size, shape, and surface area of beaver, Castor canadensis, a semiaquatic mammal

1993 ◽  
Vol 71 (5) ◽  
pp. 876-882 ◽  
Author(s):  
P. S. Reynolds
Keyword(s):  
Surface Area ◽  
Body Mass ◽  
Marine Mammal ◽  
Body Shape ◽  
Castor Canadensis ◽  
Total Surface Area ◽  
Energetic Efficiency ◽  
Terrestrial Mammals ◽  
Surface Areas ◽  
Average Surface Area

The beaver, Castor canadensis, is a large, herbivorous, semiaquatic rodent. Beaver forage on land as well as in water; thus functional compromise between competing activities should result in a less streamlined body shape than expected for a similarly sized marine mammal. Standard morphometrics and surface areas of 70 Wisconsin beaver ranging in size from 5 to 35 kg were measured. Geometric similarity of surface area was maintained during growth (i.e., area was proportional to body mass raised to the 2/3 power). Scaly-tail area was positively allometric with body mass; hind foot web area was weakly negatively allometric. The surface area of the unfurred extremities (hind feet and scaly tail) comprised 30% of the total surface area of adults and over 50% for younger beaver. The average surface area of 21 adult beaver (mean body mass = 20 kg) was 0.52 m2. This value was significantly lower (P < 0.001) than predicted from the Meeh equation for terrestrial mammals, but similar to that expected for a marine mammal of equivalent mass. Body shape was described by the fineness ratio (a hydrodynamic index of streamlining). The fineness ratio for beaver was 4.8, a value similar to that for phocid seals. Therefore, in spite of expected constraints on body shape imposed by herbivory and the competing demands of terrestrial and aquatic foraging, beaver do not differ significantly in overall shape from other, more aquatic, species. However, shape alone is not a reliable indicator of either hydrodynamic or energetic efficiency. Future comparative studies should incorporate both phylogeny and biomechanical data into evaluations of mammalian morphology.

Allometry of diving capacity in air-breathing vertebrates

1997 ◽  
Vol 75 (3) ◽  
pp. 339-358 ◽  
Author(s):  
Jason F. Schreer ◽  
Kit M. Kovacs
Keyword(s):  
Body Mass ◽  
Marine Mammals ◽  
Strong Relationship ◽  
Allometric Relationship ◽  
Air Breathing ◽  
Diving Depth ◽  
Maximum Duration ◽  
Phocid Seals ◽  
Bird Group ◽  
Taxonomic Groups

Maximum diving depths and durations were examined in relation to body mass for birds, marine mammals, and marine turtles. There were strong allometric relationships between these parameters (log10 transformed) among air-breathing vertebrates (r = 0.71, n = 111 for depth; r = 0.84, n = 121 for duration), although there was considerable scatter around the regression lines. Many of the smaller taxonomic groups also had a strong allometric relationship between diving capacity (maximum depth and duration) and body mass. Notable exceptions were mysticete cetaceans and diving/flying birds, which displayed no relationship between maximum diving depth and body mass, and otariid seals, which showed no relationship between maximum diving depth or duration and body mass. Within the diving/flying bird group, only alcids showed a significant relationship (r = 0.81, n = 9 for depth). The diving capacities of penguins had the highest correlations with body mass (r = 0.81, n = 11 for depth; r = 0.93, n = 9 for duration), followed by those of odontocete cetaceans (r = 0.75, n = 21 for depth; r = 0.84, n = 22 for duration) and phocid seals (r = 0.70, n = 15 for depth; r = 0.59, n = 16 for duration). Mysticete cetaceans showed a strong relationship between maximum duration and body mass (r = 0.84, n = 9). Comparisons across the various groups indicated that alcids, penguins, and phocids are all exceptional divers relative to their masses and that mysticete cetaceans dive to shallower depths and for shorter periods than would be predicted from their size. Differences among groups, as well as the lack of relationships within some groups, could often be explained by factors such as the various ecological feeding niches these groups exploit, or by variations in the methods used to record their behavior.

Gill and Body Surface Areas of the Carp in relation to Body Mass, With Special Reference To The Metabolism-Size Relationship

1985 ◽  
Vol 117 (1) ◽  
pp. 1-14 ◽  
Author(s):  
SHIN OIKAWA ◽  
YASUO ITAZAWA
Keyword(s):  
Special Reference ◽  
Body Mass ◽  
Body Surface ◽  
Larval Stage ◽  
The Body ◽  
Positive Allometry ◽  
Surface Areas ◽  
Gill Area ◽  
Resting Metabolism ◽  
The Relationship

The relationships of resting metabolism per unit mass of body to gill and body surface areas were examined by measuring gill, body surface and fin areas of carp ranging from 0.0016 to 2250g. There was a triphasic allometry for the relationship between gill area and body mass: during the prelarval (0.0016–0.003 g) and postlarval (0.003–0.2g) stages there was a positive allometry (slopes of 7.066 and 1.222, respectively), during the juvenile and later stages (0.2–2250 g) there was a negative allometry with a slope of 0.794. There was a diphasic negative allometry for the relationship between surface area of the body or the fins and body mass, with a slope of 0.596 or 0.523 during the larval stage and 0.664 or 0.724 during the juvenile and later stages, respectively. Except for the 3rd phase (juvenile to adult) of gill area, these slopes were significantly different (P&lt;0.01) from the slope for the relationship between resting metabolism and body mass of intact carp (0.84; value from Winberg, 1956). It is considered, therefore, that gill, body surface and fin areas do not directly regulate the resting metabolism of the fish, in the larval stage at least.

scholarly journals Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals

2014 ◽  
Vol 281 (1797) ◽  
pp. 20142103 ◽  
Author(s):  
Marlee A. Tucker ◽  
Tracey L. Rogers
Keyword(s):  
Community Structure ◽  
Body Size ◽  
Body Mass ◽  
Marine Environment ◽  
Trophic Level ◽  
Marine Mammals ◽  
Trophic Position ◽  
Trophic Levels ◽  
Predator Prey ◽  
Terrestrial Mammals

Predator–prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator–prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator–prey ratio across terrestrial ( n = 51) and marine ( n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator–prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities.

Association of serum 25-hydroxy vitamin D and body mass index in cancer

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 6625-6625
Author(s):  
D. Gupta ◽  
K. Trukova ◽  
P. G. Vashi ◽  
A. Adams ◽  
G. M. Lambert ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Vitamin D ◽  
Cancer Patients ◽  
Body Mass ◽  
Case Series ◽  
Spearman Correlation ◽  
Dietary Recommendations ◽  
25 Hydroxy Vitamin D ◽  
The Mean ◽  
The Relationship

6625 Background: The association between vitamin D and obesity remains unsettled with studies reporting conflicting findings on the relationship between the two. This association assumes even greater importance in cancer because of the alleged role of vitamin D in cancer risk and survival. Currently, the dietary recommendations for Vitamin D do not take into account a person's body mass index (BMI). We investigated the relationship between serum 25-hydroxy-vitamin D [25(OH)D] and BMI in a large sample of cancer patients. Methods: A consecutive case series of 740 cancer patients seen at Cancer Treatment Centers of America from Jan 08 to June 08. Serum 25(OH)D was measured at presentation to the hospital. The cohort was divided in 4 BMI groups (<18.5, 18.5–24.9, 25–29.9, and >30.0 kg/m2). Correlation between 25(OH)D and BMI was evaluated using Spearman correlation coefficient. Mean 25(OH)D was compared across the 4 BMI groups using ANOVA. Linear regression was used to quantify the relationship between BMI and 25(OH)D. Results: Of 740 patients, 303 were males and 437 females. The mean age at presentation was 55.7 years (SD = 10.2). The mean BMI was 27.9 kg/m2 (SD = 6.7). Most common cancers were lung (134, 18.1%), breast (131, 17.7%), colorectal (97, 13.1%), pancreas (86, 11.6%), prostate (45, 6.1%) and ovarian (39, 5.3%). The mean serum 25(OH)D was 21.9 ng/ml (SD = 13.5). Analysis revealed that as BMI groups increased from normal to overweight or obese classifications, there was a significant decrease in 25(OH)D (Table). The Spearman correlation between 25(OH)D and BMI was -0.20 (p = 0.001). Every 1 kg/m2 increase in BMI was significantly associated with a 0.43 ng/ml decline in serum 25(OH)D (p = 0.001). Conclusions: We found that obese cancer patients (BMI >=30 kg/m2) had significantly lower levels of serum 25(OH)D as compared to nonobese patients (BMI <30 kg/m2). BMI should be taken into account when assessing a patient's vitamin D status and more aggressive vitamin D supplementation should be considered in obese cancer patients. [Table: see text] No significant financial relationships to disclose.

scholarly journals Teeth complexity, hypsodonty and body mass in Santacrucian (Early Miocene) notoungulates (Mammalia)

2015 ◽  
Vol 106 (4) ◽  
pp. 303-313 ◽  
Author(s):  
Guillermo H. Cassini ◽  
Santiago Hernández Del Pino ◽  
Nahuel A. Muñoz ◽  
M. V. Walter G. Acosta ◽  
Mercedes Fernández ◽  
...  
Keyword(s):  
Surface Area ◽  
Body Mass ◽  
Tooth Enamel ◽  
Tooth Wear ◽  
Occlusal Surface ◽  
South American ◽  
Strongly Correlated ◽  
Size Dependent ◽  
Dental Traits ◽  
The Relationship

ABSTRACTNotoungulates, native South American fossil mammals, have been recently objective of several palaeoecological studies. Ecomorphology and biomechanics of the masticatory apparatus, together with micro and mesowear analyses on tooth enamel, were applied in order to understand their palaeobiology. In particular, the relationship between some dental traits (hypsodonty, occlusal surface area and complexity) and body mass is still poorly understood. These features were measured by means of the hypsodonty index (HI), occlusal surface area (OSA) and tooth area (OTA), enamel crest complexity (ECC) and length (OEL). The relationships between these indices were evaluated in five pan-contemporaneous Santacrucian Notoungulata genera from Patagonia: Adinotherium and Nesodon (Toxodontia), Interatherium, Protypotherium and Hegetotherium (Typotheria). While OSA, OTA and OEL were size dependent and strongly correlated, HI and ECC were size independent. All notoungulates analysed have very hypsodont teeth, indicating high rates of tooth wear in response to an increase of abrasives consumed with the food; their tooth occlusal area and complexity could be related to chewing efforts associated with the toughness of the plants consumed. HI, OSA and ECC were considered useful for palaeoecological reconstructions, but the results presented here show that these three features are integrated as a complex, so should not be evaluated separately.

Design of Novel Treated Silica Xerogels: Synthesis, Property and Reinforcement in Silicone Elastomers

1998 ◽  
Vol 520 ◽  
Author(s):  
Q. Deng ◽  
G. T. Bums ◽  
J. R. Hahn ◽  
C. C. Reese ◽  
J. D. Preston ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Surface Area ◽  
Silica Xerogels ◽  
Silicone Elastomers ◽  
Surface Areas ◽  
Reinforcing Fillers ◽  
Controlled Porosity ◽  
The Relationship ◽  
Filler Structure

ABSTRACTTreated silica xerogels with controlled porosity and surface area were prepared by the in-situ treatment of hydrogels with hexamethyldisiloxane in the presence of isopropyl alcohol. The resulting hydrogels were hydrophobic and readily transferred to organic solvents allowing their isolation. The surface area and porosity of the xerogel were controlled by varying the pH, time and temperature used to aggregate the hydrogel prior to treatment. The treated xerogels were evaluated as reinforcing fillers in silicone rubber formulations. When the bases were crosslinked with peroxides, silicone elastomers with acceptable mechanical properties were obtained. The relationship between the surface area, porosity and the type and degree of surface treatment of the xerogel, and its reinforcing ability was studied. In general, the mechanical properties of the elastomer increased as the filler structure increased; however, xerogels with higher surface areas were more difficult to incorporate and gave higher plasticity bases.

scholarly journals The relationship between body mass index before pregnancy and the amount of weight that should be gained during pregnancy: A cross-sectional study

2019 ◽  
Vol 35 (5) ◽  
Author(s):  
Resmiye Özdilek ◽  
Yılda Arzu Aba ◽  
Sena Dilek Aksoy ◽  
Bulat Aytek Şık ◽  
Yaşam Kemal Akpak
Keyword(s):  
Body Mass Index ◽  
Weight Gain ◽  
Pregnant Women ◽  
Body Mass ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional ◽  
The Mean ◽  
The Relationship

Objective: To investigate the adaptation of pregnant women to the recommended weight gain range according to body mass index (BMI) and to determine the factors affecting them. Methods: This cross-sectional study was performed in a university hospital’s obstetrics and gynecology unit (tertiary center) in Turkey. This study was conducted between March 2018 and August 2018 (6 months) in pregnant women. Pregnant women with chronic disease and receiving treatment during antenatal follow-up, with twin pregnancy, with a fetus with a congenital abnormality, and nutritional disturbance were excluded from the study. Eight hundred twelve pregnant women with normal antenatal follow-up and who volunteered to participate were included in the study. Results: The mean age of the participants was 27.66±5.05 years. The mean weight and BMI before pregnancy were near standard in all participants. The group with the highest rate of recommended weight gain according to BMI before pregnancy was the group with low weight pregnant women. The ideal weight gain rate in all groups was 32%. Conclusions: The groups with overweight and obese pregnant women according to BMI before pregnancy had the highest rates of weight gain, above the recommended limits. BMI before pregnancy directly affects weight gain during pregnancy and the importance of pre-pregnancy counseling and weight loss is emphasized once again. doi: https://doi.org/10.12669/pjms.35.5.133 How to cite this:Ozdilek R, Aba YA, Aksoy SD, Sik BA, Akpak YK. The relationship between body mass index before pregnancy and the amount of weight that should be gained during pregnancy: A cross-sectional study. Pak J Med Sci. 2019;35(5):---------.  doi: https://doi.org/10.12669/pjms.35.5.133 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

scholarly journals Electrocardiographic Scaling Reveals Differences in Electrocardiogram Interval Durations Between Marine and Terrestrial Mammals

2021 ◽  
Vol 12 ◽  
Author(s):  
Rhea L. Storlund ◽  
David A. S. Rosen ◽  
Andrew W. Trites
Keyword(s):  
Heart Rate ◽  
Body Mass ◽  
Marine Mammals ◽  
Physiological State ◽  
P Wave ◽  
Breath Hold ◽  
Allometric Relationships ◽  
Heart Rates ◽  
Terrestrial Mammals ◽  
Qt Intervals

Although the ability of marine mammals to lower heart rates for extended periods when diving is well documented, it is unclear whether marine mammals have electrophysiological adaptations that extend beyond overall bradycardia. We analyzed electrocardiographic data from 50 species of terrestrial mammals and 19 species of marine mammals to determine whether the electrical activity of the heart differs between these two groups of mammals. We also tested whether physiological state (i.e., anesthetized or conscious) affects electrocardiogram (ECG) parameters. Analyses of ECG waveform morphology (heart rate, P-wave duration, and PQ, PR, QRS, and QT intervals) revealed allometric relationships between body mass and all ECG intervals (as well as heart rate) for both groups of mammals and specific differences in ECG parameters between marine mammals and their terrestrial counterparts. Model outputs indicated that marine mammals had 19% longer P-waves, 24% longer QRS intervals, and 21% shorter QT intervals. In other words, marine mammals had slower atrial and ventricular depolarization, and faster ventricular repolarization than terrestrial mammals. Heart rates and PR intervals were not significantly different between marine and terrestrial mammals, and physiological state did not significantly affect any ECG parameter. On average, ECG interval durations of marine and terrestrial mammals scaled with body mass to the power of 0.21 (range: 0.19–0.23) rather than the expected 0.25—while heart rate scaled with body mass to the power of –0.22 and was greater than the widely accepted –0.25 derived from fractal geometry. Our findings show clear differences between the hearts of terrestrial and marine mammals in terms of cardiac timing that extend beyond diving bradycardia. They also highlight the importance of considering special adaptations (such as breath-hold diving) when analyzing allometric relationships.

Measurement of surface area in human mastoid air cell system

2000 ◽  
Vol 114 (2) ◽  
pp. 93-96 ◽  
Author(s):  
Moon Suh Park ◽  
Seong Hoon Yoo ◽  
Dong Hoon Lee
Keyword(s):  
Surface Area ◽  
Temporal Bone ◽  
Correlation Coefficient ◽  
Cell System ◽  
Ct Scans ◽  
Surface Areas ◽  
The Mean ◽  
Air Cells ◽  
Mastoid Air Cells ◽  
Area And Volume

The total surface areas of human mastoid air cells were measured using digital CT scans. Using 24 normal ears, the lining of the mastoid air cells was digitally scanned, traced and analysed. The mean surface area of the mastoid air cell system was 167.0.cm2 and ranged from 74.78 to 330.01 cm2. The volume was also measured, the mean being 10.43.cm3 ranging from 6.25 to 20.52.cm3. The correlation coefficient between surface area and volume was 0.95. These results indicate that well pneumatized mastoid air cells serve to provide an extremely large surface area in the temporal bone which in normal mastoid air cells is proportional to the volume.

Sign in / Sign up

Export Citation Format

Share Document