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The morphological adjustments of euhalophytes are well-known to be influenced by the soil-soluble salt variation; however, whether and how these changes in morphological traits alter the biomass allocation pattern remains unclear, especially under different NaCl levels. Therefore, an allometric analysis was applied to investigate the biomass allocation pattern and morphological plasticity, and the carbon (C), nitrogen (N), and phosphorus (P) stoichiometric characteristics of the euhalophyte Suaeda Salsa (S. salsa) at the four soil-soluble salt levels of no salt (NS), light salt (LS), moderate salt (MS), and heavy salt (HS). The results showed that soil-soluble salts significantly change the biomass allocation to the stems and leaves (p < 0.05). With the growth of S. salsa, the NS treatment produced a downward leaf mass ratio (LMR) and upward stem mass ratio (SMR); this finding was completely different from that for the salt treatments. When S. salsa was harvested on the 100th day, the HS treatment had the highest LMR (61%) and the lowest SMR (31%), while the NS treatment was the opposite, with an LMR of 44% and an SMR of 50%. Meanwhile, the soil-soluble salt reshaped the morphological characteristics of S. salsa (e.g., root length, plant height, basal stem diameter, and leaf succulence). Combined with the stoichiometric characteristics, N uptake restriction under salt stress is a vital reason for inhibited stem growth. Although the NS treatment had the highest biomass (48.65 g root box−1), the LS treatment had the highest salt absorption (3.73 g root box−1). In conclusion, S. salsa can change its biomass allocation pattern through morphological adjustments to adapt to different saline–alkali habitats. Moreover, it has an optimal biological desalting effect in lightly saline soil dominated by NaCl. [ABSTRACT FROM AUTHOR]

The morphological adjustments of euhalophytes are well-known to be influenced by the soil-soluble salt variation; however, whether and how these changes in morphological traits alter the biomass allocation pattern remains unclear, especially under different NaCl levels. Therefore, an allometric analysis was applied to investigate the biomass allocation pattern and morphological plasticity, and the carbon (C), nitrogen (N), and phosphorus (P) stoichiometric characteristics of the euhalophyte Suaeda Salsa (S. salsa) at the four soil-soluble salt levels of no salt (NS), light salt (LS), moderate salt (MS), and heavy salt (HS). The results showed that soil-soluble salts significantly change the biomass allocation to the stems and leaves (p < 0.05). With the growth of S. salsa, the NS treatment produced a downward leaf mass ratio (LMR) and upward stem mass ratio (SMR); this finding was completely different from that for the salt treatments. When S. salsa was harvested on the 100th day, the HS treatment had the highest LMR (61%) and the lowest SMR (31%), while the NS treatment was the opposite, with an LMR of 44% and an SMR of 50%. Meanwhile, the soil-soluble salt reshaped the morphological characteristics of S. salsa (e.g., root length, plant height, basal stem diameter, and leaf succulence). Combined with the stoichiometric characteristics, N uptake restriction under salt stress is a vital reason for inhibited stem growth. Although the NS treatment had the highest biomass (48.65 g root box−1), the LS treatment had the highest salt absorption (3.73 g root box−1). In conclusion, S. salsa can change its biomass allocation pattern through morphological adjustments to adapt to different saline–alkali habitats. Moreover, it has an optimal biological desalting effect in lightly saline soil dominated by NaCl.

Abstract Background Body weight scales to height with a power of ≈2 (weight/height2), forming the basis of body mass index (BMI). The corresponding scaling of body composition measured by abdominal computed tomography (CT) to height has not been established. The objective of this analysis was to quantify the scaling of body composition measured by a single‐slice axial abdominal CT image (skeletal muscle, and visceral, subcutaneous, and total adipose tissue) to height in patients with colorectal cancer (CRC). Methods This cross‐sectional study included non‐Hispanic white males and females, aged 18–80 years, who were diagnosed with stage I–III CRC at an integrated health care system in North America between January 2006 and December 2011. Body composition was measured by a single‐slice axial CT image of the third lumbar vertebra and analysed with a semi‐automated threshold segmentation procedure. Allometric regression models were used to quantify height scaling powers (β ± standard error) for each body composition measure, adjusted for age, for males and females. An interaction test was used to determine if height scaling powers were statistically significantly different between males and females. Results Among 2036 subjects, the mean (standard deviation) age was 64 ± 11 years, 1008 (49.5%) were female, and the mean (standard deviation) BMI was 27.9 ± 5.4 kg/m2. Powers for skeletal muscle area were 1.06 ± 0.12 for males and 0.80 ± 0.12 for females (P = 0.049). Powers for visceral adipose tissue area were 1.81 ± 0.64 for males and 0.57 ± 0.79 for females (P = 0.16). Powers for subcutaneous adipose tissue area were 2.04 ± 0.42 for males and 0.81 ± 0.45 for females (P = 0.056). Powers for total abdominal adipose tissue area were 1.80 ± 0.46 for males and 0.76 ± 0.50 for females (P = 0.20). Conclusions Body composition measured by single‐slice axial abdominal CT, particularly muscle area, scales to height with age‐adjusted powers that are different than 2 and are distinct between males and females. These observations may have implications for the development of height‐adjusted body composition indices in patients with cancer.

The state transition theory suggests that the decline of submerged macrophytes in shallow lakes is closely associated with reduced stoichiometric homeostasis, particularly phosphorus homeostasis (H P ). The degradation typically progresses from deeper to shallower regions, indicating a potential positive correlation between the deepwater adaptability (DA) and H P values of submerged macrophytes. Here, we investigated the distribution pattern of submerged macrophytes across different water depths of Erhai Lake to test this hypothesis. The results revealed a significant positive correlation between the DA and H P values of submerged macrophytes. Allometric analysis indicated that the morphological plasticity of submerged macrophytes was linked to their H P . Species with higher H P values, like Potamogeton maackianus, had robust plasticity strategies, particularly "real plasticity", that enabled them to cope with deeper water stress. In contrast, species with lower H P values (Ceratophyllum demersum and Hydrilla verticillata) experienced nutrient declines, which hindered their adaptation. Additionally, species with higher H P values exhibited closer connections within the plant traits-environment network, indicating that their morphological plasticity adjustments allow better adaptation to the environmental changes caused by increasing water depth. These results confirm the relationship between DA and H P in submerged macrophytes and explain the mechanisms underlying the correlation, thus expanding regime shift theory., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Hydrological variation is well-known to affect the morphological plasticity of aquatic macrophytes; however, whether these responses are size-dependent (“apparent plasticity”) or not (“real plasticity”) remains unclear, particularly with respect to the water exchange rate (WER). Here, we used allometric analysis to investigate the morphological plasticity and the carbon, nitrogen (N), and phosphorus stoichiometry of the submerged macrophyte Vallisneria natans cultured for 15, 30, 45, and 65 days under three levels of WER (0, 20, and 40% exchange of total volume day−1). We found that the negative effects of a higher WER on plant growth were primarily attributable to a deficiency in dissolved carbon dioxide, which resulted in shorter and thicker roots, smaller leaves (decreased width and length), higher specific leaf area, and lower below-: above-ground biomass ratios. Allometric analyses showed that the changes in root length reflected real plasticity, whereas other root and leaf adjustments indicated apparent plasticity. Furthermore, stoichiometric calculations indicated that N limited the growth of leaf tissues more than root tissues, thereby restricting the potential for real plasticity in leaf morphology. Therefore, V. natans adapts to WER variation largely through apparent plastic responses that can reduce the demand for plant nutrients.

How plants respond to density via modular plasticity is obscure, probably because relevant studies using covariance analysis (ANCOVA) and allometric analysis rarely focus on multiple stages of plant growth, and also the two approaches are seldom used simultaneously. In this study, a field experiment evaluated the effects of three density levels on resource allocation traits in Abutilon theophrasti and tested the degree to which these were explained by indirect effects of density on biomass over time. Results showed inconsistent responses in allocation traits and allometric relationships at each growth stage. At 30 days of plant growth, high density increased root/stem, root/leaf, and stem/leaf, but did not affect any allometric relationships. At 50 days, density altered most mass and ratio traits, but not for allometric exponents. At 70 days, density altered allometric relationships, but did not affect plant allocation patterns. The stage-dependent allometric relationships and the fact that allocation plasticity and allometric plasticity did not coincide both suggested that one-stage allometric plasticity might be apparent plasticity. In response to the increase of density, plants first altered the strategy of biomass partitioning and then growth rate or developmental stage, indicating that density effects intensified over time. For plasticity in a modular trait, size effects can be regarded as a component of (indirect) environmental effects, with the residual variation after removal of size effects being the other component of plant (direct) active response. The insights into apparent plasticity of allometry and two components of plasticity should be of essential importance to investigating phenotypic plasticity and its ecological and evolutionary implications. [ABSTRACT FROM AUTHOR]

Urban area expansion is happening at much faster rates in Asian and African cities than elsewhere in the world. This study uses multi-temporal Landsat images to map the urban extent of six small to large cities in West Africa at four different time steps from the early 1970s-2010. The selected cities are Kumasi of Ghana, Daloa of Cote d'Ivoire, Abuja and Kano in Nigeria, Kindia of Guinea, and Ouagadougou of Burkina Faso. All cities revealed significant urban growth in both urban area and population; however, it was apparent that there was a lot of variability in urban area development. Exponential urban growth rates in the cities were measured as ranging between 0.026 and 0.077, with allometric scaling factors matching those of other countries. [ABSTRACT FROM AUTHOR]

This paper presents a systematic analysis of the shellfish assemblages recovered from Heshkaia 35, an archaeological site located in the southern tip of South America. Possible arguments concerning to environmental variations and resource depression are considered in an attempt to explain taxa composition and shell size. Results are also discussed in light of expectations based on optimal foraging models and taking into account other factors beyond biological parameters. Shellfishing activities were focused on small mussels, with statistical significant changes in mean shell size along the archaeological sequence of the site. Current knowledge about past variations in sea surface temperature does not seem to explain changes in shell size. Gathering of small mussels appears to be the corollary of resource depression at a local scale. This interpretation reinforces arguments that foraging decisions would have derived from territorial packing on the southeastern coast of Tierra del Fuego during the Late Holocene. [ABSTRACT FROM AUTHOR]

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Body mass index (BMI) is now the most widely used measure of adiposity on a global scale. Nevertheless, intense discussion centers on the appropriateness of BMI as a phenotypic marker of adiposity across populations differing in race and ethnicity. BMI-adiposity relations appear to vary significantly across race/ethnic groups, but a collective critical analysis of these effects establishing their magnitude and underlying body shape/composition basis is lacking. Accordingly, we systematically review the magnitude of these race-ethnic differences across non-Hispanic (NH) white, NH black and Mexican American adults, their anatomic body composition basis and potential biologically linked mechanisms, using both earlier publications and new analyses from the US National Health and Nutrition Examination Survey. Our collective observations provide a new framework for critically evaluating the quantitative relations between BMI and adiposity across groups differing in race and ethnicity; reveal new insights into BMI as a measure of adiposity across the adult age-span; identify knowledge gaps that can form the basis of future research and create a quantitative foundation for developing BMI-related public health recommendations. [ABSTRACT FROM AUTHOR]

This work presents a comparison of the length-weight and length-length allometric relationships between six measurements: length pattern (LP), cephalic length (CL), maximum depth (MA), caudal peduncle depth (CPD) ocular diameter (OD) and weight (W) of three species of the genus Selene (S. brownii, S. vomer and S. setapinnis) caught in the port of Veracruz, Mexico, using a beach seine of 800 m. The results show certain relationships between all measurements of S. brownii (an isometric relationship and four negative allometric relationships); S. vomer showed only four relationships (two isometric and two negative allometric); and S. setapinnis showed three relationships (all negative allometric); the results of S. vomer and S. setapinnis are consistent with those reported by Muto et al. (2010). The comparison of the coefficients of allometry between the three species allowed us to determine that S. brownii and S. vomer differed significantly in two of the four allometric coefficients of length-weight relationships common to them, and in three of the four allometric coefficients of length-length relationships common to them. S. brownii and S. setapinnis differed significantly in two of the three allometric coefficients of length-weight relationships common to them and in the only allometric coefficient of length-length relationships common to them. Finally, S. vomer and S. setapinnis differed significantly in the three common allometric coefficients of length-weight relationships, and in the only common allometric coefficient of length-length relationship. [ABSTRACT FROM AUTHOR]

Background: Body mass index (BMI) is formulated on the assumption that body weight (BW) scales to height with a power of 2 (BW ∝height²), independent of sex and race-ethnicity. Powers differing from 2 are observed in studies of selected samples, thus raising the question if BMI is a generalizable metric that makes BW independent of height across populations. Objectives: The objectives were to test the hypothesis that adult BW scales to height with a power of 2 independent of sex and race-ethnicity and to advance an understanding of BMI as a measure of shape by extending allometric analyses to waist circumference (WC). Design: We conducted cross-sectional subject evaluations, including body composition, from the NHANES and the Korean NHANES (KNHANES). Variations of the allometric model (Y = αXβ) were used to establish height scaling powers (β ± SE) across non-Hispanic white and black, Mexican American, and Korean men and women. Results: Exploratory analyses in population samples established age and adiposity as important independent determinants of height scaling powers (i.e., β). After age and adiposity in the next series of analyses were controlled for, BW scaling powers were nonsignificantly different between race/ethnic groups within each sex group; WC findings were similar in women, whereas small but significant between-race differences were observed in the men. Sex differences in β values were nonsignificant except for BW in non-Hispanic blacks and WC in Koreans (P < 0.05). Nationally representative powers for BW were (NHANES/KNHANES) 2.12 ± 0.05/2.11 ± 0.06 for men and 2.02 ± 0.04/1.99 ± 0.06 for women and for WC were 0.66 ± 0.03/0.67 ± 0.05 for men and 0.61 ± 0.04/0.56 ± 0.05 for women. Conclusions: Adult BW scales to height with a power of ~2 across the 8 sex and race/ethnic groups, an observation that makes BMI a generalizable height-independent measure of shape across most populations. WC also follows generalizable scaling rules, a finding that has implications for defining body shape in populations who differ in stature. [ABSTRACT FROM AUTHOR]

A unified system of bioenergetic parameters that describe thermal regulation and energy metabolism in many passerine and non-passerine species has been developed. These parameters have been analyzed as functions of ambient temperature, and bioenergetic models for various species have been developed. The level of maximum food energy or maximal existence metabolism (MPE) is 1.3 times higher in passerines than in non-passerines, which is consistent with the ratio of their basal metabolic rates (BMR). The optimal ambient temperature for maximizing productive processes (e.g., reproduction, molting) is lower for passerines than for non-passerines, which allows passerines to have higher production rates at moderate ambient temperatures. This difference in the optimal ambient temperature may explain the variation in bioenergetic parameters along latitudinal gradients, such as the well-known ecological rule of clutch size (or mass) increase in the more northerly passerine birds. The increased potential for productive energy output in the north may also allow birds to molt faster there. This phenomenon allows passerine birds to occupy a habitat that fluctuates widely in ambient temperature compared with non-passerine birds of similar size. Passerines have a more effective system for maintaining heat balance at both high and low temperatures. The high metabolism and small body sizes of passerines are consistent with omnivore development and with ecological plasticity. Among large passerines, the unfavorable ratio of MPE to BMR should decrease the energy that is available for productive processes. This consequence limits both the reproductive output and the development of long migration (particularly in Corvus corax). The hypothesis regarding BMR increase in passerines was suggested based on an aerodynamic analysis of the flight speed and the wing characteristics. This allometric analysis shows that the flight velocity is approximately 20% lower in Passeriformes than in non-Passeriformes, which is consistent with the inverted ratio of their BMR level. The regressions for the aerodynamic characteristics of wings show that passerines do not change the morphological characteristics of their wings to decrease velocity. Passerine birds prefer forest habitats. The size range of 5-150 g for birds in forest habitats is almost exclusively occupied by passerines because of their large energetic capability. [ABSTRACT FROM AUTHOR]

Soybean breeding is typically conducted in soils with favourable soil phosphorus yet soil P levels are typically low in sub-tropical regions. This study was conducted to determine yield progress of soybean cultivars released between 1995 and 2016 in sub-tropical parts of south-west China and grown at both low and high P availability. The principal factors that changed indirectly with breeding and that contribute to soybean yield were also determined. Field experiments were conducted in three consecutive years with two different sites each year. A more detailed investigation of traits contributing to soybean yield was investigated in one year at two sites. The rate of genetic gain in seed yield was around 2% per year and this was found at both low P and high P. Thus, breeding under favourable conditions has also resulted in substantial gains in soils with low P. Yield gains were attributed to a longer duration of pod filling but there was no change in the duration from sowing to flowering. The extended pod filling duration increased both above-ground biomass and harvest index (HI) at both P levels and both were important in contributing to yield gains. The increase in HI was also a result of the changed allocation of assimilates away from stems and instead to the pods and growing seeds. The allometric analysis (ratios between log transformations of the leaf, stem and pod dry weight) showed that the stem weight decreased as pod dry weight became heavier whereas leaf weight remained constant as stems became lighter as a result of breeding. Breeding also progressively increased pod number and the total seed number but there was no change in average seed weight. • Soybean breeding conducted under favourable soil P levels has successfully increased seed yield in soils with favourable and unfavourable P levels. • The rate of genetic gain between 1995 and 2016 in south-west China is around 2% per year in both high and low P soils. • Yield gains have been attributed to both an increase in above-ground dry weight and an increase in harvest index. • Breeding has not increased seed weight but seed number has increased. [ABSTRACT FROM AUTHOR]

Abstract: Olive oil yield is the product of fruit weight and oil concentration at maturity; knowledge of the dynamics and allometric relationships of these components could help understanding the genotypic, environmental and management sources of variation in oil yield. The aims of this work were to: model the dynamics of fruit weight, oil and water concentration in olive varieties; quantify the relationship between the dynamics of fruit component in terms of rate and duration and their responses to environmental factors and explore the relationship between oil yield components using an allometric approach. Ten olive varieties were monitored during two seasons in Mendoza (32°S), Argentina. The evolution of fruit weight and concentration of oil and water (from pit hardening to maturity were fitted with bilinear functions and the parameters derived (maximum, rate, onset and duration) were associated with weather variables. Across seasons, fruit fresh weight (wt) (range from 252 to 749mg), fruit wt-filling rate (0.1–0.3mg°Cd−1) and fruit wt-filling duration (2288–2913°Cd) exhibited significant genotypic variation. The fruit wt-filling rate accounted for 91% of the variation in fruit fresh wt. Fruit fresh wt and fruit wt-filling rate varied between seasons while no significant differences were found for fruit wt-filling duration. Fruit oil concentration (45.5–57.4%) and duration (2425–2876°Cd) varied among varieties, but was largely unaffected by season. Oil-filling duration was the most important term in determining the fruit oil concentration (P =0.0013). During fruit growth, fruit water concentration remained stable at its maximum and declined linearly when fruit reached maximum fresh weight and oil concentration. Fruit oil concentration decreased with increasing maximum daily temperature (P =0.04) and solar radiation (P =0.01). [Copyright &y& Elsevier]

The power that the birds can use for flight (available power) and the power required for flight according to physical laws (requisite power) grow with an increase in body mass, the exponents of the corresponding functions being different. Small birds can follow different strategies, either improving the aerodynamic quality of the body (thereby saving the excess available power) or sacrifice aerodynamic quality in favor of morphological adaptation to factors other than the demands of flight proper, which provides the possibility of utilizing a wider range of ecological niches. A hypothesis is proposed that the high metabolic rate of passerine birds, compared to representatives of other bird orders, is an adaptation to maneuverable (i.e., relatively low-speed) flight necessary for successful colonization of forest habitats. The speed that birds of such size can develop according to the scaling theory is too high for nesting and foraging in tree crowns, and its reduction is possible in two ways: by increasing air drag or by changing the style of flight (by analogy with airplane vs. helicopter). The first way is feasible, but a high air drag due to morphological modifications (e.g., in the size of the tail or characteristics of the wing) interferes with the possibility of long-distance migration flight, as energy expenditures for it will exceed the energy potential of the bird. This is why migratory nonpasserine birds, which have used this strategy, are practically absent in forests of the temperate zone. Therefore, more promising is the second way involving transition to a new flight style and, in a certain sense, to a new morphophysiological organization. Passerines have achieved this by changing their flight style so that the wing actively generates forces (lift and thrust) only in downstroke. Such a flight requires more energy, and, to provide it in sufficient amounts, passerine birds have increased their basal metabolic rate ( BMR). Thus, both their flight energy expenditures and BMR are higher than in nonpasserines. Remarkably, among approximately 8660 extant bird species known today, more than half (about 5100 species) belong to the order Passeriformes. Such a ratio, unknown in any other vertebrate class, is evidence that passerines have gained a considerable biological advantage over all other birds due to their increased BMR. [ABSTRACT FROM AUTHOR]

The article discusses results of a study that analyzes the relationship between body weight (W) and pharmacokinetic parameters for orbifloxacin. Correlations across nine mammal species were made using the parameters of interest such as volume of distribution at steady state (Vss), clearance (Cl) and half-life elimination. The mammal species used in the study include dog, rat, goat, cattle and camel. The study showed that the parameter increases with W approximates a relationship of linear power with slopes close to one. The study indicated the possibility to use allometry to predict orbifloxacin's pharmacokinetic variables.

[Display omitted] • We analyzed allometric responses of V. natans to water exchange rate (WER). • V. natans could use both apparent and real plasticity to acclimate to WER. • Apparent plasticity was more frequently adopted due to low nutrient demand. Hydrological variation is well-known to affect the morphological plasticity of aquatic macrophytes; however, whether these responses are size-dependent ("apparent plasticity") or not ("real plasticity") remains unclear, particularly with respect to the water exchange rate (WER). Here, we used allometric analysis to investigate the morphological plasticity and the carbon, nitrogen (N), and phosphorus stoichiometry of the submerged macrophyte Vallisneria natans cultured for 15, 30, 45, and 65 days under three levels of WER (0, 20, and 40% exchange of total volume day−1). We found that the negative effects of a higher WER on plant growth were primarily attributable to a deficiency in dissolved carbon dioxide, which resulted in shorter and thicker roots, smaller leaves (decreased width and length), higher specific leaf area, and lower below-: above-ground biomass ratios. Allometric analyses showed that the changes in root length reflected real plasticity, whereas other root and leaf adjustments indicated apparent plasticity. Furthermore, stoichiometric calculations indicated that N limited the growth of leaf tissues more than root tissues, thereby restricting the potential for real plasticity in leaf morphology. Therefore, V. natans adapts to WER variation largely through apparent plastic responses that can reduce the demand for plant nutrients. [ABSTRACT FROM AUTHOR]

Abstract: The allometric equations relating the half-life, the volume of distribution and the total body clearance of gentamicin, amikacin, tobramycin, kanamycin and apramycin to body weight for mammalian and mammalian+avian species were defined. Literature data were used as a source of comparative pharmacokinetic data. For all antibiotics examined half-life intercepts ranged from 0.49 to 1.66, slopes from 0.05 to 0.45, volume of distribution intercepts – 0.13–0.75, slopes – 0.77–1.41, total body clearance intercepts – 0.88–8.8 and slope – 0.62–1.04. A better relationship between pharmacokinetic parameters and body weight was shown when all values were included in the allometric analysis. Different values of intercept and slope between birds and mammals were found in gentamicin and apramycin studies. In some cases, slopes and intercepts changed when all values of pharmacokinetic parameters were included. We conclude that small difference exist between pharmacokinetics of gentamicin, amikacin, tobramycin, kanamycin and apramycin. The allometric equations shown in our study provide a basis to estimate dose intervals for mammals and birds for which specific information is lacking. [Copyright &y& Elsevier]

Abstract: Allometric analysis was used to examine morphological relationships in field populations of two clonal plants, Cladium jamaicense and Typha domingensis, in a Florida Everglades wetland. We found that allometric relationships of individuals sampled from field populations could be adequately derived and applied to analyzing both leaf and ramet growth responses to site differences along a nutrient gradient. Overall, the allometric relationships showed a significant departure from isometry which indicates that the relationships were size-dependent. Leaf-level morphological relationships were significantly different between species and between sites along the nutrient gradient. These differences, however, were not expressed on the ramet-level. Neither species expressed a plastic allocation response to site differences along the nutrient gradient. Biomass allocation between above- and below-ground for both species indicated significant size-dependent relationships with decreasing relative allocation below-ground with increasing size. Models for predicting total plant biomass (above- and below-ground) for both C. jamaicense and T. domingensis were developed based on two non-destructive measurements that are easily obtainable in the field. The models followed the equation log(biomass)= α + β 1 ×log(height)+ β 2 ×log(basal area), where α was species specific while β 1 and β 2 were similar for both species but significantly different according to site along the nutrient gradient. Analysis of this model showed that plant height had a relatively greater influence on biomass than basal area at all sites. This difference was greatest at the un-enriched area where plants tend to be short and thick and the least at the moderately enriched site where the relative influence of both parameters was similar. [Copyright &y& Elsevier]

Background: Body weight scales to height with a power of ≈2 (weight/height 2 ), forming the basis of body mass index (BMI). The corresponding scaling of body composition measured by abdominal computed tomography (CT) to height has not been established. The objective of this analysis was to quantify the scaling of body composition measured by a single-slice axial abdominal CT image (skeletal muscle, and visceral, subcutaneous, and total adipose tissue) to height in patients with colorectal cancer (CRC)., Methods: This cross-sectional study included non-Hispanic white males and females, aged 18-80 years, who were diagnosed with stage I-III CRC at an integrated health care system in North America between January 2006 and December 2011. Body composition was measured by a single-slice axial CT image of the third lumbar vertebra and analysed with a semi-automated threshold segmentation procedure. Allometric regression models were used to quantify height scaling powers (β ± standard error) for each body composition measure, adjusted for age, for males and females. An interaction test was used to determine if height scaling powers were statistically significantly different between males and females., Results: Among 2036 subjects, the mean (standard deviation) age was 64 ± 11 years, 1008 (49.5%) were female, and the mean (standard deviation) BMI was 27.9 ± 5.4 kg/m 2 . Powers for skeletal muscle area were 1.06 ± 0.12 for males and 0.80 ± 0.12 for females (P = 0.049). Powers for visceral adipose tissue area were 1.81 ± 0.64 for males and 0.57 ± 0.79 for females (P = 0.16). Powers for subcutaneous adipose tissue area were 2.04 ± 0.42 for males and 0.81 ± 0.45 for females (P = 0.056). Powers for total abdominal adipose tissue area were 1.80 ± 0.46 for males and 0.76 ± 0.50 for females (P = 0.20)., Conclusions: Body composition measured by single-slice axial abdominal CT, particularly muscle area, scales to height with age-adjusted powers that are different than 2 and are distinct between males and females. These observations may have implications for the development of height-adjusted body composition indices in patients with cancer., (© 2021 The Authors. Journal of Cachexia, Sarcopenia and Muscle published by John Wiley & Sons Ltd on behalf of Society on Sarcopenia, Cachexia and Wasting Disorders.)

Purpose. To evaluate the distribution of allometric exponents for relationship of total plasma clearance of 54 extensively metabolized drugs, with wide-ranging linear clearance values, between humans and rats, to provide a rationale for the observed data, and to discuss potential significance of the findings. Methods. Human and rat plasma clearance values of 54 drugs with markedly different physicochemical properties were obtained from the literature. Standard allometric analysis was performed for each drug using both rat and human data. Unbound vs. total plasma clearances were obtained for 15 out of 54 drugs and their correlations between humans and rats were compared. Results. The mean ± SD of the allometric exponent for the 54 drugs studied is 0.660 ± 0.190. The median clearance ratio based on unit body weight is 7.41 and the median exponent is 0.645. Excluding two outliers the correlation coefficient of plasma clearance between humans and rats was 0.745 (p < 0.0001). For the 15 drugs, use of unbound plasma clearance approach seems to significantly improve the correlation coefficient compared to total plasma clearance (0.940 vs. 0.841). Conclusions. The present study indicates that on average, humans and rats may eliminate extensively metabolized drugs at a rate similar to that expected from the allometric or body surface area relationship of basal metabolic rate between the two species. A simple statistical distribution hypothesis is used to rationalize the species difference in plasma drug clearance. Rat may serve as an useful animal model to predict (unbound) plasma clearance of drugs in humans. [ABSTRACT FROM AUTHOR]

• Teal carbon assessments of baldcypress swamps can be improved by including knee contributions. • Baldcypress knees are taller and heavier in flooded, mid-latitude climates of the Mississippi River Alluvial Valley (MRAV) • Knee carbon biomass may represent as much as 5.2–17.9% of the live standing biomass of swamp forests. Carbon stock trends of the knees of Taxodium distichum likely vary across climate gradients of the southeastern United States and contribute an unknown quantity of "teal" carbon to inland freshwater wetlands. Knee metrics (e.g., density, height, biomass) were measured in mixed T. distichum swamps across the Mississippi River Alluvial Valley (MRAV) from Illinois to Louisiana. Based on their geometric similarity to a cone, the biomasses of field knees were estimated by relating the volume of their measured field dimensions to lab-measured water displacement volume and biomass via volume/mass regressions (biomass (g) = 7.2230149 + 0.292902 × volume). Knees had greater height in flooded conditions (maximum height = 163 cm; Goose Lake, Arkansas), and also in climate normal environments of mid-range precipitation and temperature (p < 0.0001). Overall, knee biomass ha−1 was 7.5 times greater in flooded vs. not flooded conditions (34.6 ± 7.3 vs. 4.6 ± 1.0 Mg ha−1, respectively). The overall mean of knee carbon biomass stock was substantial (flooded vs. not flooded conditions: 18.1 ± 3.7 Mg C ha−1 to 2.9 ± 0.7 Mg C ha−1, respectively; knee/tree live standing biomass: 17.9–5.2%, respectively). Clearly, T. distichum knees should not be ignored in blue (teal) carbon discussions of wetlands. Because knees respond to climate normal conditions, hotter/drier environments in the MRAV could lead to a decline in the contribution of knee carbon stock in the southeastern United States. [ABSTRACT FROM AUTHOR]

Summary: Phenotyping adults for excess adiposity and related health risks usually include three body size measurements: height, weight and waist circumference (WC). Height and weight are now widely used as components of the body shape measure, body mass index (BMI, weight/height2), with the height power referred to as the scaling factor, α. At present, WC is usually not adjusted for height or is expressed as WC/height in which α = 1. Although other α values have been proposed, a critical review of these shape measures is lacking. Here, we examine classical pathways by which the scaling exponent for height used in BMI was developed and then apply this strategy to identify the optimum WC index characteristic of adult shape. Our analyses explored anthropometric, body composition and clinically‐relevant data from US and Korean National Health and Nutrition Surveys. Our findings provide further support for the WC index of WC/height0.5 as having the strongest associations with adiposity while having the weakest correlations with height across non‐Hispanic white and black, Mexican American and Korean men and women. The WC index, defined as WC/height0.5, when combined with BMI, can play an important role when phenotyping adults for excess adiposity and associated health risks in research and clinical settings. [ABSTRACT FROM AUTHOR]

Abstract The variation in reproductive investment (RI) and the hypothesis of multiple spawning were evaluated in the redfinger rubble crab Eriphia gonagra (Fabricius, 1781). The gonads and embryos showed synchronous development, and fecundity and RI varied widely among females of the same size class. The mean RI value recorded was 11.31%, with no significant differences among the means for different size classes. The allometric analysis of fecundity indicated RI decrease while body size increase, but we suggested that this occurs due to size overestimation where the largest width of carapace was used as body size reference in these analyzes. In addition, we found an isometric relationship for “female weight vs. egg number”, and also for “female weight vs. egg weight”, indicating that RI increased proportionally with size of females. Relatively high frequencies both of smaller females with rudimentary gonads, and of larger females with developed gonads were observed. This indicates that larger females take place more frequently in the population reproductive output over time. This difference could not be observed by means of RI analyses of captured and fixed crabs, for which only one stage of gonad development and/or one spawning is usually recorded.