Dissertations / Theses: 'Allometria'

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SBARRA, PAOLA. "Contributo della geomorfologia quantitativa alla caratterizzazione morfologica e morfodinamica di alcuni paesaggi italiani." Doctoral thesis, La Sapienza, 2005. http://hdl.handle.net/11573/917391.

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Tannenbaum, Stacey Jill. "Pharmacokinetic principles of allometry and allometric, pharmacokinetic, and pharmacodynamic analyses of cocaine and ethanol." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/280341.

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This dissertation deals with two major topics: allometric (or interspecies) scaling of pharmacokinetic parameters, and the interaction of cocaine and ethanol. These topics are tied together by the inclusion of allometric analyses of both cocaine and ethanol. Currently, to make initial predictions of human pharmacokinetic parameters using allometry, allometric slopes of 0.75, 1.0, or 0.25 (for clearance, volume, and half-life, respectively) are applied to the appropriate parameter value measured in a single species. Chapter 1 demonstrates the validity of this practice, and, using literature data on many diverse compounds, suggests that the monkey is the best species for predicting human data. Chapter 2 uses allometric principles to show that hepatic extraction ratio (ER) is independent of body weight, and thus constant across species. This is due to the fact that ER is the ratio of two parameters with identical allometric slopes, hepatic clearance and blood flow. Chapter 3 demonstrates that cocaine can be scaled using allometric relationships, leading to reasonably accurate predictions of the parameters in humans. Chapter 4 shows that the pharmacokinetic parameters of ethanol can be scaled allometrically. This was previously thought to be impossible, since ethanol undergoes saturable elimination, and as a result, the pharmacokinetic parameters (clearance and half-life) are dose-dependent. By scaling other parameters that are dose-independent, such as the Michaelis-Menten parameters, predictions of human concentration-time plots can be simulated. The co-administration of cocaine and ethanol is shown to cause a superadditive response. This is a result of two mechanisms: ethanol inhibits cocaine clearance, thus increasing cocaine concentrations, and, an active metabolite, cocaethylene, whose effects are similar to that of cocaine, is formed in vivo after co-administration of the two drugs. Because this drug combination is so common, and because of the resultant increased risk of toxicity and death, it is important to understand how much cocaethylene is formed after co-administration of cocaine and ethanol. Chapter 5 outlines a procedure used to calculate the fraction of cocaethylene formed after co-administration of the two drugs. Chapter 6 then summarizes the pharmacokinetic-pharmacodynamic models of cocaine given alone, compared to the combination.

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Buchmann, Carsten. "Modelling the structuring of animal communities in heterogeneous landscapes : the role of individual home range formation, foraging movement, competition and habitat configuration." Phd thesis, Universität Potsdam, 2012. http://opus.kobv.de/ubp/volltexte/2012/5903/.

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This thesis aims at a better mechanistic understanding of animal communities. Therefore, an allometry- and individual-based model has been developed which was used to simulate mammal and bird communities in heterogeneous landscapes, and to to better understand their response to landscape changes (habitat loss and fragmentation).
Diese Doktorarbeit strebt ein besseres mechanistisches Verständnis von Tiergemeinschaften an. Dafür wurde ein allometrie- und individuen-basiertes Modell entwickelt und dazu benutzt, Säugetier- und Vogelgemeinschaften in heterogenen Landschaften zu simulieren, und ihre Reaktion auf Landschaftsveränderungen (Habitatverlust und -fragmentierung) besser zu verstehen.

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Paquin, Viviane. "Allometric gender allocation in Ambrosia artemisiifolia L." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ55924.pdf.

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Tang, Huadong. "Allometric scaling for predicting human drug clearance." Diss., The University of Arizona, 2005. http://hdl.handle.net/10150/290158.

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Various modified methods have been proposed in response to criticisms regarding the practical applicability of allometric scaling, which is one of the most widely used approaches in predicting human drug clearance based on data from animal species. The major problems encountered among allometric methods in predicting human drug clearance are addressed in this dissertation. In chapter 2, a large data set for allometric scaling (n = 138) was collected from the literature and was categorized according to the following criteria: oral or systemic clearance; elimination routes; protein or non-protein chemicals; low, intermediate, or high metabolic clearance. Some significant observations have been made regarding the applicability of allometric scaling according to the pharmacokinetic and physical-chemical properties of the drugs examined. Of special note, several potential rules were developed for when one could expect large vertical allometry. In chapter 3, a new model for predicting human clearance was developed. The new model was shown to provide better predictability than any other current approach. In particular, the new model for the first time predicts the occurrence of large vertical allometry noted in humans. In chapter 4, a general equation was derived, which directly describes the mathematical relationship between predicted pharmacokinetic (PK) parameters in humans and the body weights of animals and the values of their corresponding measured PK parameters. This relationship clearly illustrates the species or body weight-dependency of the prediction performance by allometric scaling. Finally, real data from the literature demonstrated the species-dependency predicted from the equation. In chapter 5, the functionality of the correction factors, maximum life-span potential (MLP) and brain weight (BrW) in allometry is mathematically described for the first time. It was found that corrections by MLP or BrW are equivalent to a multiplication of certain constants by the predicted values in humans from simple allometry and has nothing to do with any measured values of PK parameters in any animal species. The role of correction factors (MLP and BrW) or "rule of exponents" in species scaling was evaluated.

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Senarathna, Senarathna Mudiyanselage Dona Kalyani Ganga. "Pharmacokinetics and allometric scaling of antimalarial drugs." Thesis, Curtin University, 2015. http://hdl.handle.net/20.500.11937/1139.

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Allometric scaling was found as a plausible technique for dose determination in children. Permeability and P-glycoprotein efflux transport of antimalarials were determined using in-vitro Caco-2 cells. Mefloquine showed P-glycoprotein inhibition. Amodiaquine, artesunate and artemisone were not P-glycoprotein substrates or inhibitors. Methylene-blue showed some P-glycoprotein mediated efflux. Permeability was high for amodiaquine and artemisone, medium for mefloquine and artesunate and low for methylene-blue. P-glycoprotein was up-regulated when exposed to dihydroartemisinin/artemisone in combinations with amodiaquine/mefloquine.

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Bowers, Jennifer L. "Evolution and development of allometric relationships in 'Antirrhinum'." Thesis, University of East Anglia, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443088.

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Castilho, L. V. "The developmental basis of allometry." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597361.

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This thesis investigates the role played by molecular signalling pathways in organ size determination in Drosophila melanogaster. First, the analysis of wing mosaics generated by mitotic recombination showed that both the insulin receptor InR and its downstream target chico have a strong and largely local autonomous reducing effect on wing size. Position of the mutant tissue in the mosaic wings determines the intensity of size deficits, since the posterior wing compartment is more severely affected than the anterior. A second insulin receptor was analysed and shown to perform no role in size determination. Additionally, the TGF-b/activin surface receptor babo causes much weaker size reductions, even though cells deficient for the gene have extreme difficulty to proliferate. This corroborates the idea that genes with an important role in cell proliferation do not necessary play a major role in determining final organ size. Finally, the small size phenotype of vein mutants (a member of the EGF pathway) was reassessed, and the results did not corroborate previous claims that the reduced size of vein mosaic wings is caused by an overall reduction of the wing. On the contrary (and consistently with the action of insulin and TGF-beta pathway genes), vein seems not to interfere with the size of adjacent non-vein regions of the mosaics. This adds a question mark to Garcia-Bellido's Entelechia model of wing development. A second issue addressed in this project is the known interaction between size and environmental factors. It is widely believed that the insulin pathway is responsible for converting nutrient availability into growth. Such hypothesis implies that the size of insulin pathway mutants should respond less than wildtype flies (or not respond at all) to starvation. Experiments showed that in fact chico and InR mutants do not respond to starvation, contrary to the intense size decrease observed in malnourished wildtype flies.

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Fritz, Julia. "Allometrie der Kotpartikelgröße von pflanzenfressenden Säugern, Reptilien und Vögeln." Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-75540.

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Stock, Jay Theodore. "Structural and allometric variability in human long bone diaphyses." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ31870.pdf.

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Jackson, Brandon Edward. "The allometry of bird flight performance." The University of Montana, 2010. http://etd.lib.umt.edu/theses/available/etd-03102010-100229/.

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Avian flight performance decreases with body size in birds, but previous work has been unable to define the underlying mechanism. Wingbeat frequency is hypothesized to ultimately constrain flight performance via muscular mechanical power output because frequency decreases with body size. I measured maximal burst take-off and vertical accelerating flight in 32 species of songbirds (Passeriformes), including the entire range of body mass in this clade (5-900 g). Jump forces against the ground were recorded with a forceplate. High-speed digital video captured the movement of morphological landmarks in order to estimate aerodynamic power requirements and dynamic morphology in flight. Surgically implanted gauges recorded the components of muscle power (muscle length change, force production, frequency) in the four largest species (Common raven, American crow, Black-billed magpie, and Gray jay). Flight performance and total aerodynamic power scaled with negative allometry, but were significantly influenced by foraging ecology. Species that forage on the ground had relatively lower jump impulses, shorter wings, higher wingbeat frequencies, and higher power output than species that forage on elevated substrates. I also found two unexpected internal scaling patterns. Both proportional muscle length change (muscle strain) and average cross-sectional area specific force (muscle stress) increased with size. Longer wingbeat cycles may permit more complete muscle activation in larger birds, thereby partially compensating for the constraint imposed by wingbeat frequency. These data offer the strongest support and the only direct evidence for power-limited scaling of flight performance to date.

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Jackson, Brandon Edward. "The allometry of bird flight performance." Diss., [Missoula, Mont.] : University of Montana, 2009. http://etd.lib.umt.edu/theses/available/etd-03102010-100229.

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Mansfield, Fiona Kerrie. "Allometric scaling in bacterial populations : cell size, distribution and diversity." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424704.

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HAGIHARA, Akio, 秋男萩原, Taketo YOKOTA, 岳人横田, Kazuharu OGAWA, and 一治小川. "Allometric Relations in Hinoki (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.) Trees." 名古屋大学農学部付属演習林, 1993. http://hdl.handle.net/2237/8694.

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Wirkes, André Franz [Verfasser]. "Allometrie des intrazellulären Surfactants der Lunge bei Säugetieren / André Franz Wirkes." Gießen : Universitätsbibliothek, 2013. http://d-nb.info/1065320639/34.

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Kritzinger, Werne Jacobus. "Allometric description of ostrich (Struthio camelus var. domesticus) growth and development." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6469.

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Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011.
Includes bibliography.
ENGLISH ABSTRACT: The ostrich industry has overcome many challenges since it originated. However, it is still vulnerable to sudden changes in customer preferences and economic cycles. As feed costs are the greatest expense in ostrich production, optimising feed formulations is vital. This will be possible if the growth and development of the ostrich can be simulated by modelling software. Various studies were conducted to describe ostrich growth in the form of equations that can be used in modelling software to increase the accuracy of predictions. In the first study, birds were given the choice of four diets with varying energy (8.5 or 13.5 MJ ME/kg feed) and protein (180 or 120 g/kg feed) levels. The birds preferred the high density diet (high energy and protein) in each growth phase. A growth curve of assumed optimal growth was constructed. The chemical fractions of the body were shown to increase non-linearly with advancing age and equations were established to predict the change of the body composition over time. In the second trial, birds received a formulated growth diet and were fed according to their nutrient requirements. Growth data was collected on the separate body components of maturing birds. Feather and skin nodule growth was defined for birds hatched in the summer. Allometric equations were set up to determine, predict and model the ostrich skin size and skin weight, some bones, some organs and the commercially valuable muscles through the growth cycle. The final trial was conducted to determine the effect of diet density (energy and amino acid level) on the growth of ostrich body components. A four-stage, 3 x 5 (energy x protein) factorial design was developed with varying energy and protein feeding regimes. Protein (amino acid) level had no influence on body component growth. Energy level had no effect on feather growth, skin nodule growth, bone and organ growth and muscle growth. Increased levels of dietary energy increased the skin size and skin weight. Increasing the dietary energy level also had a significant effect on the total body fat of the birds. Allometric equations were set up for each variable to predict the effect of diet on ostrich growth. Results in this study provide a framework for simulation modelling. Predicting ostrich growth and development is paramount to accurate diet formulations and lower feeding costs.
AFRIKAANSE OPSOMMING: Die volstruisindustrie het reeds vele struikelblokke oorkom, maar bly steeds kwesbaar vir skielike veranderinge in die ekonomiese klimaat asook in die voorkeure van die verbruiker. Een van die belangrikste insetkostes in volstruisproduksie is voer en daarom is dit noodsaaklik om voerformulerings te optimiseer. Die doel van hierdie tesis was om by te dra tot die ontwikkeling van modellering sagteware wat die groei en ontwikkeling van die volstruis naboots. Die spesifieke doel was om volstruisgroei te bestudeer en te bespreek deur middel van vergelykings wat gebruik kan word om die akkuraatheid van die simulasiemodelle te verhoog. Tydens die eerste studie is die voëls die keuse van vier diëte gegee waarvan die energie- (8.5 of 13.5 MJ ME/kg voer) en proteïen- (180 of 120 g/kg voer) vlakke verskil het. Die voëls het in die hoëdigtheid voer (hoog in energie en proteïen) in elke groeifase gekies. Uit hierdie data, wat aanvaar is om optimale groei te verteenwoordig, is ‘n groeikurwe gekonstrueer wat getoon het dat die chemise komponente van die liggaam nie-linieêr toegeneem het oor tyd. Vergelykings is hieruit afgelei wat die verandering in die liggaamsamestelling oor tyd kan voorspel. In die tweede studie het die voëls ŉ vier-fase geformuleerde groeidieët ontvang en is na gelang van hulle voedings behoeftes gevoer. Groeidata is ingesamel van die individuele liggaams-komponente van die groeiende volstruise. Veer- en velgroei is gedefinieer vir die voëls wat in die somer uitgebroei het. Allometriese vergelykings is opgestel om te bepaal hoe die volstruis se velgrootte, velgewig, sekere bene en organe, asook die kommersiële belangrike spiere gedurende die groei-siklus verander. Die finale studie is uitgevoer om die effek van voedingsvlak (energie- en aminosuurvlak) op die groei van die volstruis se liggaamskomponente te bepaal. ŉ Vier-fase, 3 x 5 (energie x proteïen) faktoriale ontwerp is gebruik met veranderende energie- en proteïenvlakke. Proteïen- (aminosuur) vlakke het geen invloed op die groei van die liggaamskomponente gehad nie. Energievlak het geen effek op die veer-, vel-, velknoppie-, been-, organe- en spiergroei gehad nie. Toenemende vlakke van energie het wel gelei tot ŉ toename in die velgrootte en massa. Die toename in voedingsengergie-vlakke het ook ŉ betekenisvolle effek op die totale liggaamsvet van die voëls gehad. Allometriese vergelykings is opgestel vir elk van die veranderlikes om die effek van dieët op elke komponent van die volstruis te bepaal. Die resultate van hierdie studies verskaf ‘n raamwerk vir die simulering en modellering van die groei en ontwikkeling van die volstruis. Akkurate voorspellings van die groei en ontwikkeling van die volstruis is noodsaaklik vir akkurate dieëtformulering en verlaagde voedingskostes.

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Goulão, João Pedro Pinto. "Influence of metabolic stress in bovine fetal development : an allometric study." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2021. http://hdl.handle.net/10400.5/21168.

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Dissertação de Mestrado Integrado em Medicina Veterinária
Dairy cows go through great metabolic change during the transition period, with several detrimental side effects on health and productivity. The possibility that the stress they undertake on the final phase of gestation can also influence the unborn calf or even have carryover effects that will impact him after birth is not one that should be ignored. The main goal of this study was to determine if calves born from metabolic stressed cows prioritized the development of vital organs, brain and heart specifically, over the development of the long bones, more precisely the radius-ulna and the metatarsus. Additionally, differences between countries, particularly environmental, were also considered as a possible aggravator of metabolic stress and, consequently, of allometric fetal development. For the purposes of this study, the head diameter and circumference (HD and HC, respectively), chest circumference (HG), forearm and metatarsal lengths (FL and ML, respectively), hip and shoulder width (HW and SW, respectively), height (WH) and diagonal length (DL) of 171 newborn Holstein Friesian calves from one farm in Portugal and two farms in Belgium were measured with callipers and a measuring tape. The dam’s milk production for the year (M305d), parity and gemelarity, as well as the season when the measurements were performed, were also registered. Measurement ratios (HC/ML, HC/FL, HD/ML, HD/FL, HG/ML and HG/FL) were used as an indicator of prenatal allometric growth and analysed against the data obtained from the mothers. Some significant correlations were evidenced (P<0.05) in the belgian calves, between the ratios with parity and season, demonstrating a tendency towards higher ratios with the increase of these two variables. However, the portuguese calves supported none of these results. This discrepancy obtained from the analysis of the portuguese and belgian calves, probably the result of an insufficient sample size, led us to believe that the conclusions drawn from this study are most likely premature and that further studies should be conducted in order to clarify them. Subsequently, the relation between metabolic stress and fetal development also remains unclear and should be the subject of further investigation.
RESUMO - Efeitos do stress metabólico no desenvolvimento do feto bovino: estudo sobre alometria - Durante o período de transição as vacas de leite enfrentam enormes alterações metabólicas com repercussões na sua saúde e produtividade. Face à possibilidade de que o stress nesta última fase da gestação pode também influenciar o feto, ou até mesmo ter efeitos secundários que irão afetar o vitelo, esta é uma área de estudo que não pode ser ignorada. O objetivo deste estudo pretende determinar se, na presença de stress metabólico materno, há prioridade no desenvolvimento de órgãos vitais no feto, como o cérebro e o coração em específico, sobre o desenvolvimento dos ossos longos, mais precisamente o rádio-ulna e o metatarso. Adicionalmente as diferenças entre países, particularmente ambientais, foram consideradas como um possível fator agravante do stress metabólico que, consequentemente, poderia realçar diferenças na alometria dos órgãos em estudo. Para os propósitos deste estudo, várias medições foram realizadas em 171 vitelos recém-nascidos de raça Holstein Frísia com um medidor ósseo e uma fita métrica. Foram medidos o diâmetro e a circunferência da cabeça (HD e HC, respetivamente), a circunferência do peito (HG), o comprimento do antebraço e do metatarso (FL e ML, respetivamente), a largura das ancas e dos ombros (HW e SW, respetivamente), a altura (WH) e o comprimento diagonal (DL). Os vitelos em questão foram medidos nas respetivas explorações, uma exploração de vacas leiteiras em Portugal e duas na Bélgica. Também foram recolhidos outros dados provenientes dos registos das explorações como a produção leiteira do ano (M305d), a paridade e a gemelaridade das mães, e a época e temperatura em que foram realizadas as medições. Os rácios das medições (HC/ML, HC/FL, HD/ML, HD/FL, HG/ML e HG/FL) foram utilizados como indicadores de alometria dos órgãos fetais em estudo e analisados em relação aos dados obtidos das vacas. Algumas conexões significativas (P<0.05) foram evidenciadas nos vitelos belgas, entre os rácios com a paridade e a época de medição. Os rácios demonstram uma tendência em crescer com o aumento dessas duas variáveis. No entanto, os vitelos portugueses não comprovaram nenhum destes resultados. Esta discrepância entre as análises dos vitelos portugueses e belgas, provavelmente causada por uma amostra insuficiente, levam-nos a crer que as conclusões tiradas deste estudo são prematuras e que deveriam ser realizados estudos adicionais de modo a esclarecê-las. Subsequentemente, a relação entre o stress metabólico e o desenvolvimento do feto também se mantém incerta e deverá continuar a ser investigada.
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Zhang, Da. "Evaluation of the Allometric Exponents in Prediction of Human Drug Clearance." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3533.

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Background. Allometric scaling (AS) is widely used in predicting human clearance (CL) based on animal data. Substantial prediction errors have been commonly observed and various modifications to AS have not provided a broad reliable improvement. In this study, an extensive data set was assembled including animal and human systemic CL and physiochemical properties. The allometric exponents were calculated based on multiple species AS and single-species AS methods. The correlations between the allometic exponents and physiochemical properties were evaluated in an attempt to find covariates that may explain the inter-compound variability in the allometric exponents. Lastly, the statistical approaches in analyzing the allometric function were evaluated with the collected data. Methods. 1- A nonlinear mixed effect modeling (MEM) approach was performed to investigate the central tendency and distribution of AS exponents as well as to identify whether there are any correlations between the allometric exponent, and coefficient, with the physicochemical and drug metabolism and pharmacokinetics (DMPK) properties of the compounds. 2- Single-species AS was performed to estimate the single-species AS exponent distributions and their corresponding central tendencies. The correlation between the estimated single-species AS exponents and the physicochemical and DMPK properties of the compounds were also examined. 3- The methodologies of log-log transformation followed by linear regression (LL-LR) and direct nonlinear regression methods (NLS) with different weighting schemes on the AS power function were investigated. The central tendency and distribution of the allometric exponents were evaluated and compared across methods. Furthermore, the human CL prediction performance was evaluated among methods. Results. The estimated central tendency and distribution of AS exponents from the nonlinear MEM as well as the single-species AS approaches were consistent with literature reports. There were no significant correlations identified between the estimated AS exponents and the physicochemical or DMPK properties. The methods of LL-LR and the NLS with 1/w2 weighting (variance weighted by CL2 during the variance minimization process) results in the most similar allometric exponent with central tendency around 0.668 and provided the best human CL prediction among methods investigated. Conclusion. The knowledge gained in this work by extensive modeling and simulations contributed to a better understanding of the variability in AS exponents and better practice in performing AS in human CL prediction

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Tang, Evonne P. Y. (Evonne Pui Yue). "The allometry of algal growth and respiration." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22815.

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A knowledge of the allometry of algal growth and respiration can be applied to biomass-size distribution models which are in turn used in the prediction of fish yield and ecosystem studies. However, the scaling exponents reported in the literature are variable. This variation may be attributed to differences in the expression of cell size and phylogeny, but could also reflect small sample size which underlie most published regressions. This thesis establishes the allometry of algal growth and respiration based on a larger sample taken from the literature, and evaluates the effects of differences in gross taxonomy and in the expression of cell size on these relations. Allometric relations based on cell carbon appear more consistent with relations from other taxa than those based on cell volume, reflecting the size dependence of algal elemental composition which does not occur in most other taxa. The allometric relation of algal respiration (R in pl O$ rm sb2 cdot cell sp{-1} cdot hr sp{-1})$ was found to be R = 0.030C$ sp{0.93}$ where C is cell carbon content in pg C$ rm cdot cell sp{-1}$. Among the 6 divisions studied (Chlorophyta, Chrysophyta, Cyanophyta, Euglenophyta, Pyrrophyta, Rhodophyta), chlorophytes, euglenophytes and rhodophytes exhibited different respiration-size relation but separate relations were not developed for each of those groups due to patterns in residuals or small sample sizes. The specific rate of algal growth ($ mu$ in divisions$ cdot$day$ sp{-1}$) also depends on size and it is found to be $ mu$ = 3.45C$ sp{-0.21}.$ All taxa studied here (Chlorophyta, Chrysophyta, Pyrrophyta) have similar scaling exponents for growth but Pyrrophyta have significantly lower growth rates than other algae of similar size.

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Dang, Thi Thu Huong, Huu Thu Do, Minh Quang Trinh, Hung Manh Nguyen, Thi Tuyet Xuan Bui, and Tien Dung Nguyen. "Allometric relations between biomass and diameter at breast height and height of tree in natural forests at Me Linh Station for Biodiversity, Vinh Phuc Province, Vietnam." Technische Universität Dresden, 2018. https://tud.qucosa.de/id/qucosa%3A33298.

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Stem diameter at breast height (D1.3m) and tree height (H) are commonly used measures of tree growth. Based on correlation analysis between biomass of stem, branches and leaves and stem diameter and height of tree we can identify allometric equation for predicting biomass and carbon sequestration of the vegetation. This study was carried out in the natural forests of Me Linh Station for biodiversity to develop allometric equation between biomass and diameter at breast height and height of tree. The study results indicated that twenty tree species dominate in natural forests in Me Linh Station for Biodiversity and they were selected for sampling. Through the 80 established linear equation models for above and below –ground biomass (AGB and BGB), we found that the biomass of tree species in Me Linh Station for Biodiversity were closely correlated with the diameter factor (R>0.902) and not clearly correlated with the height (correlation coefficient = 0.5498, R2< 0.549). Four regression equations were established, including: Pstem = 25.3051*(D1.3m)0.4627 (R2 : 9.661); Pbranch = 12.1043*( D1.3m)0.5416 (R2 : 9.8); Pleaves = 9.446*(D1.3m)0.5976 (R2 : 0.9363); P total biomass of forest = 25.882*D1.725 with R2: 0.8561) for estimating biomass and carbon sequestration of natural forest at the research site.
Đường kính ngang ngực (D1.3m) và chiều cao (H) cây là hai nhân tố thường được dùng để đánh giá sự phát triển của cây gỗ. Việc xây dựng các phương trình tương quan giữa sinh khối (SK) thân, cành, lá, sinh khối tầng cây gỗ, sinh khối của quần xã thực vật với đường kính và chiều cao cây góp phần rất lớn trong dự báo sinh khối và khả năng hấp thụ khí carbon của thảm thực vật. Kết quả nghiên cứu cho thấy 20 loài cây gỗ chiếm ưu thế trong rừng tự nhiên và chúng được chọn để thu mẫu. Mối tương quan giữa sinh khối với 2 nhân tố điều tra rừng là đường kính ngang ngực và chiều cao cây đã đươc kiểm tra thông qua 80 phương trình tương quan. Nhìn chung, sinh khối có tương quan chặt chẽ với nhân tố đường kính (hệ số tương quan R > 0,902), và không tương quan rõ với nhân tố chiều cao (R < 0,5498). Bốn phương trình tính sinh khối cho thảm rừng tại khu vực nghiên cứu đã được thiết lập: SKthân = 25,3051*(D1,3m)0,4627 (R2: 9,661); SKcành: 12,1043*(D1,3m)0,5416 (R2: 9,8); SKlá: 9,446*(D1,3m)0,5976 (R2: 0,9363) và SKtổng = 25,882*D1,725 with R2: 0,8561).

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21

Hackney, John W. "Morphometric variability and allometric relationships in the seagrass Thalassia testudinum in Florida Bay /." Electronic version (PDF), 2003. http://dl.uncw.edu/etd/2003/hackneyj/johnhackney.pdf.

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22

George, Keith Phillip. "Left ventricular morphology : the impact of menstrual cycle phase, oral contraceptive use, body size, body composition and athletic training." Thesis, Manchester Metropolitan University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246262.

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23

Wiff, Rodrigo. "Predicting food consumption and production in fish populations : allometric scaling and size-structured models." Thesis, University of St Andrews, 2010. http://hdl.handle.net/10023/935.

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Life-history traits in fish populations are highly correlated. A subset of these correlations are called allometric scaling, they refer to biological processes which can be described using body size as independent variable. Particularly, allometric scaling related with food consumption (Q) and biomass production (P) has gained the attention of ecologists for several decades. This thesis proposes a quantitative framework for food consumption, which allows both the identification of the mechanisms underlying the allometric scaling for Q and the development of a predictive model for consumption to biomass ratio (Q/B) in fish populations. This thesis is based on the fact that food consumption can be inferred from first principles underlying the von Bertalanffy growth model. In addition, it has been noticed in the literature that biomass production and food consumption show similar allometric scaling dependence, therefore, both can be derived from these first principles. Thus, a similar quantitative framework was used to produce models for P/B in fish populations. Once functional forms for production and food consumption were identified, a third model was developed for the ratio between production and consumption (P/Q). This ratio is usually named ecological efficiency because it determines how efficiently a population can transform ingested food into biomass. Several authors have noticed that P/Q remains invariant (independent of body size) across species. From a theoretical point of view, the results presented here allow the first quantitative explanation for the existence of the allometric scaling for Q/B and the invariance of P/Q across fish species. These results, together with the explanation for allometry in P/B reported in the literature, suggest that the regular across-species pattern for the trio {P/B,Q/B,P/Q} can be explained by basic principles that underpin life-history in fish populations. This quantitative framework for the trio {P/B,Q/B,P/Q} is based on an explicit dependence with body size, which simplifies the estimation of these quantities. Model complexity depends, in part, on which data are available. Models were applied to real data from commercially important species fished in Chile. Statistical properties of the new models were evaluated by an intensive resampling approach. The simplest possible model for the trio {P/B,Q/B,P/Q} rests on the assumption of a stable age distribution. These quantities have a key importance in ecosystem modelling because they determine population energetics in terms of food intake by predation and the transformation of this energy into population biomass of predators. Application of the new models produces results which were comparable to those given by standard methods. This thesis is a result of multidisciplinary research which attempts to make a contribution to the understanding of the mechanisms underlying the allometric scaling of food consumption and production in fish populations. It proposes models for the trio {P/B,Q/B,P/Q} and thus, has the potential to be widely applicable in fisheries science.

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24

Smith, Joanna McLellan. "Effects of allometric growth and toe pad morphology on adhesion in hylid tree frogs." Thesis, University of Glasgow, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398660.

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25

Tod, Steven Peter. "What drives invertebrate communities in a chalk stream : from trophic relationships to allometric scaling." Thesis, Queen Mary, University of London, 2007. http://qmro.qmul.ac.uk/xmlui/handle/123456789/28174.

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Despite a slow start freshwater meiofauna research is now gathering pace. Evidence is accumulating which indicates the importance of their inclusion in lotic metazoan studies. Here I contribute towards this research effort by conducting an investigation of meiofauna and macrofauna from a chalk stream. I sampled meiofauna for a 19 month period, and macrofauna for a 12 month period between April 2004 and October 2005 from the subsurface, macrophyte stands and gravel beds. The chalk stream community was highly diverse with 57 taxa identified from the subsurface and 186 from the benthos. Meiofauna outnumbered macrofauna in all habitats in terms of density. Both meio- and macroinvertebrates preferred macrophyte stands over gravel beds as habitat, indicated by higher densities, biomass and species richness. Speciesabundance relationships and density-size spectra indicated the invertebrate assemblages of the benthos to be stable over the period of the study as patterns varied little between sampling months and habitats. Production and standing biomass were dominated by the macroinvertebrates which suggests meiofauna had a limited role within functioning of the stream. However, gut content data indicated meiofauna may play an important trophic role, linking basal resources and top consumers. Combined gut content and stable isotope analysis suggested a strong pattern of generalist feeding throughout the whole spectrum of body size in the community, rejecting the concept of functional feeding groups. Predominance of generalist feeding also suggested a large number of weak interactions in food webs. While higher species richness lower in food webs indicated greater functional redundancy of lower trophic levels. Density-body size distributions were shallow with a biased distribution of energy towards larger size classes. Moreover, testing of production, standing biomass and PIB body size allometry was inconclusive with regards to theoretical predictions. The interrelationship ofbiodiversity, stability, and trophic dynamics, with body size determine the structure and dynamics of the chalk stream community, not metabolism.

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26

Gowda, Vishwas, and Vishwas Gowda. "Allometric Scaling of Brain, Brain Components and Neurons with Body Size of Social Bees." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/621438.

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Animals in general vary immensely in body size, which greatly affects their morphology, physiology, survival, and nutritional requirements. The nervous system is also affected by variation in body size, which, in turn, shapes the perception of environmental stimuli and the behavior of animals. Comparative studies of vertebrates suggest that larger brains and their integrative centers comprise more and generally larger neurons (Jerison, 1973; Kaas, 2000), but much less is known about brain - body size relations in invertebrates. Closely related social bee species are well suited to study correlations between body size and brain composition. Different honey bee species vary in body size yet differ little in their ecological requirements and behavior and bumble bees feature a large range of body sizes even within a single colony.

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27

Brown, Calum. "The metabolism of living space : allometric scaling of energy use in UK domestic buildings." Thesis, Lancaster University, 2015. http://eprints.lancs.ac.uk/81388/.

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Understanding and reducing domestic energy usage is seen as key to achieving national greenhouse gas emission targets, as well ensuring sustainable consumption at a domestic level. Domestic buildings represent a well-defined unit of space with numerous, easily measurable characteristics. They can also be perceived as being the terminal, end-use elements of a global resource distribution network, as defined by Jarvis et al., (2015). Such networks have drawn comparisons to biological organisms in how they acquire, transform, use and dispose of resources from their surrounding environment through a metabolic system of processing. This thesis aims to more deeply understand interrelations between, people, energy and space at a domestic level, assessing the influence of building geometry and social practices on scaling relationships relating to domestic energy consumption. Scaling relationships relating to the physical building properties have been studied extensively, however none directly assess how total energy usage scales across the domestic building stock. Data is abstracted form the 2012 English Housing Survey (EHS) housing stock dataset, which contains physical and demographic data relating to ~14k randomly sampled households across England. Scaling relationships are established between household size and total energy usage, both across the entire housing stock and by selected building characteristics, revealing scaling effects pertaining to specific domestic properties. Across the entire housing stock, a scaling exponent of 0.8032 ± 0.013 is observed for the relationship between household total floor area and total energy consumption, indicating a decrease in energy use per unit space with increased household size. This result is set within a context of building geometric properties and theories of societal metabolism, drawing extensively on current literature and this researches own findings. Understanding the origins of such scaling could potentially hold important implications for how individuals perceive their energy consumption, both in relation to physical domestic buildings and wider society.

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28

Suzuki, Satoshi. "Study on skull allometry in the genus Mustela (Carnivora: Mustelidae)." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157817.

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29

Loh, Eugene E.-M. "Allometry Of Fixed Orthodontic Appliances - A Study Of Bracket Thickness." Thesis, Faculty of Dentistry, 1993. http://hdl.handle.net/2123/4242.

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30

Blossman-Myer, Bonnie Burggren Warren W. "A contravention of established principles of interspecific allometric metabolic scaling in developing silkworms, Bombyx mori." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3704.

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31

Blossman-Myer, Bonnie. "A Contravention of Established Principles of Interspecific Allometric Metabolic Scaling in Developing Silkworms, Bombyx Mori." Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3704/.

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Established interspecific metabolic allometric relationships do not adequately describe the complexity and variable physiological states of developing animals. Consequently, intraspecific allometric relationships of oxygen consumption and carbon dioxide production as a function of body mass; the respiratory quotient; the function of the silk cocoon; and body composition were investigated for each distinct developmental stage of the silkworm, Bombyx mori. Whole animal O2 consumption in Bombyx ranged from 0.00064 + 0.000047 ml O2 .hr-1 at larval instar I to 0.77 + 0.06 ml O2 .hr-1 in pre-pupal, falling to 0.21+ 0.01 ml O2 .hr-1 in the pupae. Those instars having a significant relationship between O2 consumption as a function of body mass, the slope of the line relating O2 consumption to body mass varied between 0.99 and 1.02, while across all instars the slope was 0.82. Developmental allometry should be presented for individual developmental stages because the individual allometric exponents of the stages can be significantly different from the overall allometric exponent throughout development and in some cases, the overall allometric exponent can be a statistical artifact. The first larval instar of Bombyx mori has the lowest cross sectional area of high metabolic tissue of the midgut (27%) and had one of the highest percentages of some metabolically inert tissues (i.e. lipid, 7.5%). Body composition of the first instar does not support the idea that smaller mass animals having the highest O2 consumption are composed of a greater percentage of metabolically active organs when compared to larger animals. However, this developmental stage has the highest percentage of the mitochondrial marker cytochrome oxidase, which correlates well with the high O2 consumption rate of the smaller mass. Therefore, established interspecific principles should not be assumed to function as valid models for intraspecific developmental relationships of metabolism as a function of body mass. Developmental allometry should include an analysis of individual stages of development as well as an analysis of development as a whole to gain a comprehensive understanding of the complexity of allometry of the developing animal such as the silkworm.

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32

Wei, Xiaofang, Subramania I. Sritharan, Ramanitharan Kandiah, and John Osterberg. "Allometric Equations for Predicting Above-ground Biomass of Tamarix in the Lower Colorado River Basin." University of Arizona (Tucson, AZ), 2012. http://hdl.handle.net/10150/556805.

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Allometric equations are essential for quantitative study of aboveground biomass. The paper presents an effort in acquisition and validation of allometric equation for salt cedar (Tamarix spp.), a species that has been criticized for its invasion and negative impacts on the riparian ecosystem in the western United States. In the summers of 2009 and 2011, biomass destructive samplings were conducted to harvest and collect salt cedar samples at Cibola National Wildlife Refuge, Arizona. The allometric equations were developed by establishing the relationship between aboveground biomass with average basal diameter, tree height, and total basal area. The validity and the strength of the allometric models were examined with the adjusted coefficient of determination (r²), standard error of estimate (SSE), and Akaike Information Criterion (AIC). Total basal area was identified as the best predictor for salt cedar biomass, followed by tree height. Average basal diameter was a poor predictor. In linear equations, total basal area accounted for 78.4 percent of the total variation in aboveground biomass. In logarithmic equations, tree height and total basal area together explained 87.7 percent and yielded the small AIC and SSE. These equations will advance the quantitative estimation of salt cedar biomass and provide useful information for studying evapotranspiration, water consumption, and carbon storage.

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33

Bennett, P. M. "Comparative studies of morphology life history and ecology among birds." Thesis, University of Sussex, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379453.

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34

Schreer, Jason Franklin. "Diving behavior of air-breathing vertebrates, allometry, classification, and interspecific comparisons." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/nq22235.pdf.

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35

Schneider, Florian Dirk [Verfasser], Ulrich [Akademischer Betreuer] Brose, and Nico [Akademischer Betreuer] Blüthgen. "Predator diversity and ecosystem functioning: An allometric approach / Florian Dirk Schneider. Betreuer: Ulrich Brose ; Nico Blüthgen." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2012. http://d-nb.info/1106257219/34.

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36

Roberts, David Gordon. "An allometric analysis of the cardiac and pulmonary systems of the blue wildebeest (Connochaetes taurinus taurinus)." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/62568.

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This study describes the growth of the blue wildebeest (Connochaetes taurinus taurinus) cardiac and pulmonary systems with ontogenetic allometric equations, contributing an additional species to the small collection of ontogenetic allometric studies on mammals. Allometric equations of the form 𝑦𝑦=𝑎𝑎𝑥𝑥𝑏𝑏 were derived to describe the changes in cardiac or pulmonary measurements (𝑦𝑦), with change in body mass and heart or lung mass (𝑥𝑥). The body masses used in these equations were calculated from external body measurements, to compensate for temporary changes in individual body mass. Different mass estimation equations were investigated to choose the most suitable method. Forty-three post-natal blue wildebeest (22 male, 21 female; body mass 74 - 258 kg), and five foetuses, with (12 and 15 kg; gestational age approximately 7 months) were measured. All animals were sourced from culling operations on the Bubye Valley Conservancy in southern Zimbabwe, in different seasons, over three years. Body mass (𝑀𝑀𝑏𝑏) in kilograms was most accurately predicted from body length (𝐿𝐿) and girth (𝐺𝐺) in meters: 𝑀𝑀𝑏𝑏=39.08(𝐿𝐿𝐿 2)0.909 (R2 = 0.935, PPEA=8.2%) or 𝑀𝑀𝑏𝑏=64.34𝐺𝐺2.58 (R2 = 0.911, PPEA=9.4%). These equations are mildly affected by both sex and season. The equations predict significantly lower body masses (p<0.001) than similar equations for East African subspecies. Blue wildebeest heart mass (𝑀𝑀ℎ) scales hypoallometrically with body mass and ranges from approximately 0.8% of body mass in the foetus to 0.5% of body mass in adult. Heart growth follows the allometric equation: 𝑀𝑀ℎ=0.0118𝑀𝑀𝑏𝑏0.832 (R2 = 0.846, PPEA=10.9%) in the post-natal animal. While the dimensions of the left heart grow isometrically with heart mass, the thickness of the right ventricular wall does not appear to change significantly after birth. This change in thickness may be due to the change in the function of the right ventricle at birth. The lung mass in kg (𝑀𝑀𝑙𝑙) and tracheal volume in ml (𝑉𝑉𝑡𝑡) follow the allometric equations: 𝑀𝑀𝑙𝑙=0.0260𝑀𝑀𝑏𝑏0.816 (R2 = 0.71, PPEA=16) and 𝑉𝑉𝑡𝑡=3.31𝑀𝑀𝑏𝑏0.905 (R2 = 0.78, PPEA=16) in the post-natal animal, which are not significantly different from isometry (p>0.05). The relative lung masses of foetal wildebeest are significantly greater and the foetal trachea relatively narrower than in post-natal animals. Growing wildebeest heart masses are lower than found in horses and giraffes, larger than in buffalo and similar to those of cattle of the same body mass. Their lung masses are smaller than those of horses but larger than those of giraffes. Interspecific equations for mammals predict larger heart and lung masses than measured in post-natal wildebeest, but not significantly so (heart: p=0.11 and lung: p=0.83). However, the difference between measured and predicted heart mass, when only adult wildebeest are considered, is statistically significant (p=0.016). In conclusion, blue wildebeest body mass can be predicted from external body measurements and heart, lung and tracheal measurements scale with body mass. Heart growth is hypoallometric to body mass and lung mass scales isometrically with body mass. Throughout growth, the heart and lung masses of wildebeest are not different from those predicted for average mammals.
Dissertation (MSc)--University of Pretoria, 2017.
Production Animal Studies
MSc
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37

Bailey, Susan J. "Climate change : carbon partitioning in plants." Thesis, University of Plymouth, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263166.

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38

HernaÌndez, Antonio Valencia. "Assessment of allometry and length-at-age in the growth of fishes." Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275048.

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39

Hood, William Gregory. "Landscape allometry of oligohaline tidal channels of the lower Chehalis River, Washington /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/5399.

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40

Levitch, Linda Charlotte. "Ontogenetic allometry of the postcranial skeleton in platyrrhines, with special emphasis on its relationship to the evolution of small body size in the callitrichidae /." Thesis, Connect to this title online; UW restricted, 1987. http://hdl.handle.net/1773/6467.

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41

Ehnes, Roswitha [Verfasser], Ulrich [Akademischer Betreuer] Brose, and Nico [Akademischer Betreuer] Blüthgen. "Allometry – Relations to Energy and Abundance / Roswitha Ehnes. Betreuer: Ulrich Brose ; Nico Blüthgen." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2014. http://d-nb.info/1108094430/34.

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42

Adam, Peter James. "Morphological evolution in Cetacea skull asymmetry and allometry of body size and prey /." Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1375523531&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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43

Yáñez, Enrique Alejandro [UNESP]. "Desenvolvimento relativo dos tecidos e características da carcaça de cabritos Saanen, com diferentes pesos e níveis nutricionais." Universidade Estadual Paulista (UNESP), 2002. http://hdl.handle.net/11449/104975.

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Made available in DSpace on 2014-06-11T19:33:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-10-04Bitstream added on 2014-06-13T19:23:39Z : No. of bitstreams: 1 yanez_ea_dr_jabo.pdf: 472965 bytes, checksum: 1e3d450b0ba9483da550c43e4a8cf69f (MD5)
Foram realizados dois experimentos utilizando cabritos machos da raça Saanen. O primeiro teve por objetivo avaliar o desenvolvimento relativo dos componentes do peso vivo (PV), dos cortes comerciais e dos tecidos de caprinos leiteiros em crescimento. Tomando como referência o corte perna, o tecido ósseo apresentou crescimento precoce, o muscular isométrico e o adiposo crescimento tardio, sendo a gordura subcutânea depositada mais tardiamente. Os cortes comerciais apresentaram coeficiente de alometria isogônico com exceção dos cortes 6a a 13a costelas e peito/fralda. O desenvolvimento da carcaça e dos não-componentes da carcaça acompanhou o peso de corpo vazio, enquanto que a pele e cabeça+patas apresentaram coeficiente heterogônico negativo e o trato digestório coeficiente isogônico. Os cabritos com 35 kg de PV e 15,5 kg de carcaça apresentaram adequadas proporção de músculo e relação músculo:osso, mas maior proporção de gordura que os animais abatidos com 20 kg de PV. O segundo experimento foi desenvolvido em duas fases (5 a 20 e 20 a 35 kg de PV) e teve por objetivo avaliar os efeitos da restrição alimentar sobre as características da carcaça, e estimar equações para predizer características da carcaça a partir de medidas biométricas. Foram determinadas as medidas biométricas e a condição corporal nos animais vivos, e após o abate e resfriamento de 24 h, as medidas e compacidade da carcaça. As carcaças foram seccionadas em sete cortes e a perna dissecada em osso, músculo e gordura. O aumento da restrição alimentar produziu diminuição na proporção do lombo e aumento na do pescoço, na Fase 1. Na Fase 2 o lombo e 6a a 13a costelas diminuíram sua participação com o aumento da restrição e a paleta e o pescoço aumentaram. A proporção de ossos aumentou e a de gordura total diminuiu com o aumento da restrição nas duas fases...
Two experiments were developed with male Saanen kids. The objective of the first was to evaluate the relative development of the live weight components, of the commercials joints and of the kids dairy goat at growing tissues. The bones showed earlier development, the muscle was isometric and the fat later developing, but the subcutaneous fat was later developing than intermuscular fat. The commercials joints exhibited isogonic allometric coefficient with except of the 6a to 13a ribs and brisket. The development of the carcass and non-carcasses components followed the empty body weight, but the skin and head+paw showed earlier development and the gastrintestinal tract showed isometric coefficient. The kids goat with 35 kg LW and 15,5 kg of the carcass exhibited adequate muscles proportion and muscle:bone rate, but with higher fat rate than animals slaughter with 20 kg LW. The second experiment was developed in two phases (5 to 20 and 20 to 35 kg LW) and the objective was to evaluate the feed restriction effects in the carcass characteristics, and to estimate the equation that was allowed predict the characteristics of the carcass from the biometrics measures. It were determinated the biometrics measures and the corporal condition in the live animals, and after of the slaughter and chilling at 24 h, it were established the measures and compactness of the carcass. The carcasses were sectioned in seven commercials joints and the leg dissected in bone, muscle and fat. The increase of the feed restriction provide decrease in the loin proportion and the neck increase, of the Phase 1. On the Phase 2, the loin and the 6a to 13a ribs decreased their participation with the increase of the restriction and the shoulder and the neck increased. The proportion of the bones increased and the total fat decrease due high feed restriction in both phases... (Complete abstract, access undermentioned eletronic address)

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44

Price, Charles Anthony. "Scaling the Diversity of Botanical Form and Function." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/194373.

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Recent theoretical and empirical advances, in particular the fractal branching model of West, Brown and Enquist (WBE model), have highlighted the importance of exchange surfaces in understanding the integration of whole plant form, and functional traits. Key insights have arisen from an increased understanding of how the properties of distributive vessel networks influence whole plant metabolic and physiological traits. Here I show that an extension of WBE model, one in which network geometry is continuously variable, provides a robust foundation to understand the diversity of scaling relationships in plants and the organs of which they are composed. Central to the original WBE model has been the assumption of energy minimization as a selective force shaping the evolution of internal and external plant surface areas and morphology. Here I demonstrate how additional selection on traits not detailed in the original WBE formulation can lead to departures from strict energy minimization, and can thus explain much of the variation and covariation in observed scaling central tendencies in plant gross morphology observed within, and across natural plant communities. I test the predictions from this model extension with data from both regional and global datasets, from the leaf to whole plant level, across herbaceous, succulent, woody, annual and perennial taxa. These data demonstrate that the model extension is quite robust and should serve as a foundation upon which more detailed future models can be constructed.

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Genet, Astrid. "Quantification of fuelwood potentials from French beech forests : updated allometric modeling tools and robustness to differences in soil fertility." Chambéry, 2010. http://www.theses.fr/2010CHAMS040.

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Un jeu d'équation de biomasse robuste a été développé pour le hêtre sur des arbres provenant de trois pays Européens. Les paramètres des modèles sont apparus âge-dépendants, et l'introduction de l'âge des peuplements dans les équations a permis d'en augmenter significativement la performance pour tous les compartiments aériens de l'arbre. Cet effet a été relié à des changements de forme et de densité du bois dans le tronc, et à des changements dans la conductance hydraulique des tissus pour le houppier. L'introduction de l'âge des peuplements parmi les variables prédictives du modèle est la clé de la précision des équations développées, la sylviculture et la fertilité du site étant à l'origine des faibles variations résiduelles. Afin de confirmer ce résultat, nous sommes parvenus à homogénéiser la plupart des équations hêtre publiées en prenant en compte l'âge des peuplements utilisés en calibration donné dans chaque papier original. En perspective, nous avons remarqué que nos résultats suivaient le même schéma que ceux obtenus sur l'Eucalyptus. Sur la base de mesures expérimentales, nous avons évalué l'impact des propriétés du sol sur les schémas de répartition de la biomasse et les immobilisations en éléments minéraux dans l'arbre. Nous avons mis en évidence l'importance de la fertilité des sols lors de l'intensification des prélèvements forestiers pour le bois-énergie. L'exploitation des rémanents, sauf compensée par fertilisation, doit être limitée aux sols riches où les exportations minérales seront compensées par les cycles externes. L'écorçage peut-être une solution pour compenser les pertes en Ca sur sols acides. Enfin, un modèle économique qualitatif met en évidence les déterminants de l'offre et de la demande en bois-énergie. Ces observations ont permis de défini des hypothèses quant aux propriétés d'un modèle économétrique. Il n'a cependant pas pu être ajusté faute de données disponibles. Une réflexion sur la procédure statistique à mettre en œuvre a été menée
Working on European beech, a set of robust biomass allometric equations was developed using trees from hree European countries. Models allometric parameters were round to vary with stand age and its introduction in the equations significantly improved the performances of aboveground biomass equations. Age effect was related to changes in bath form and wood density of the trunk and to changes in hydraulic conductance of the crown. Introducing stand age among the parameters is the key of the accuracy of our equations, management option and stand fertility standing for the low residual variations. To confirm this result, we were able to homogenize most of the published biomass equations by accounting for the stand age given in each original paper. With stand age in perspective, we noticed that our results matched the patterns observed for Eucalyptus. At a larger scale and based on experimental measurements, we assessed the impact of varying soil properties on biomass partitioning pattern and nutrient immobilisations in tree. Using the model we developed, we highlighted the importance of considering soil fertility when planning intensified harvesting practices, particularly in the case of fuelwood-oriented scenarios. The removal of forest residues, unless compensated by fertilisation, should be considered carefully and limited to nutrient-rich soils where external inputs could guarantee the durability of the nutrient cycle. By debarking stem, Ca exportations on critical acid soils can be seriously limited. On soils we studied along the pedosequence, whole tree harvesting scenarios could be considered on rendisol-calcisols and oligosatured-brunisols. In a last time, we were interested in assessing social implications of the system studied. A qualitative economic model highlighting the economic, social and environmental determinants of supply and demand for fuelwood was established. Hypotheses regarding the properties of an econometric model were drawn from those observations. Model specifications could not be tested because available information was not sufficient to carry on with robust econometric estimation. A reflexion about implementable statistical procedure was carried out. A system GMM approach seems indicated in this context

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46

Brym, Zachary T. "An Allometric Approach to Evaluate Physiological and Production Efficiencies in Tree Size for Tart Cherry and Apple Orchard Systems." DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/4970.

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Improving production efficiency is a major challenge for modern orchard systems. The primary response in horticulture is to develop high-density orchard systems that use dwarfing rootstocks and intense management strategies to maintain small tree size. As development and evaluation of novel orchard systems may help improve understanding of plant physiology for the development of high-density systems. The effect of tree size and architecture on physiological and production efficiency was evaluated for tart cherry (Prunus cerasus, P. mahaleb) and apple (Malus spp.) orchard systems using a physiologically driven modeling approach, called allometry. Branch dimensions, canopy dimensions and biomass were measured for 24-year-old tart cherry individuals and 10-year-old 'Golden Delicious' apple individuals on various rootstocks in experimental blocks at the Kaysville Research Farm in Davis Co., Utah. Tree size was related to annual fruit biomass that had been collected over the duration of the apple trial. Branch dimensions, canopy dimensions, yield, and fruit quality were collected in commercial tart cherry orchards of Utah Co. Tree size, architecture, and biomass of tart cherry and apple expressed strong allometric relationships that were broadly consistent among the two orchard tree species and the theoretical expectations derived from wild plants. The most consistent relationship was the trunk diameter (or trunk cross sectional area) - stem biomass relationship, which broadly followed the 8/3-power law. Branch and canopy dimensions that include a measure of length, such as branch length and canopy height, demonstrated architecture indicative of high water efficiency and metabolic activity that is relieved from biomechanical constrains of weight bearing. The apple rootstocks differed from each other in production efficiency with individuals that express smaller branch and canopy dimensions producing a higher proportion of fruit relative to tree size. In the commercial tart cherry orchards, smaller individuals with relatively higher canopy height and spread expressed higher yield and fruit quality. Overall, this research supported the continued development of training systems that maintain small trees to improve physiological and production efficiency. Further research must reconcile other consequences of intense management and overproduction that arise with the increased efficiency facilitated by small tree size and high-density orchard systems to maintain sustainable fruit production.

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Regis, Koy William. "Allometry of sexual size dimorphism in turtles| A comparison of mass and length data." Thesis, Tarleton State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10118551.

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The macroevolutionary pattern of Rensch’s Rule, i.e., positive allometry of sexual size dimorphism, has had mixed support in turtles. Using the largest carapace length dataset and the only large-scale body mass dataset heretofore assembled for this group, we determine (a) whether turtles conform to Rensch’s Rule at the order, suborder, and family levels, and (b) whether inferences regarding allometry of sexual size dimorphism differ based on choice of body size metric used for analyses. We compiled large databases of mean body mass and carapace length for males and females of as many populations and species as possible using mostly primary literature. We then determined scaling relationships between males and females for average body mass and straight carapace length across species of turtles using traditional and phylogenetic comparative methods. We also used linear regression analyses to evaluate sex-specific differences in the variance explained by carapace length on body mass.

In non-phylogenetic analyses, body mass supports Rensch’s Rule, whereas straight carapace length supports isometry. Using phylogenetic independent contrasts, both body mass and straight carapace length support Rensch’s Rule with strong congruence between body size metrics. More variance is explained by mass than carapace length. At the family level, support for Rensch’s Rule is more frequent when mass is used as a body size metric and in phylogenetic comparative analyses. Turtles do not differ in their mass-to-length regressions by sex. Turtles display Rensch’s Rule overall and within some families of Cryptodires, but not in Pleurodire families. At broad scales, mass and length are strongly congruent with respect to Rensch’s Rule in turtles, and discrepancies are observed mostly at the family level (which is the level where Rensch’s Rule is most often evaluated). At macroevolutionary scales, the purported advantages of length measurements over weight measurements are not supported in these ectothermic vertebrates.

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Hoffmann, Madonna Bridget, and Madonna hoffman@dpi qld gov au. "Application of tree and stand allometrics to the determination of biomass and its flux in some north-east Australian woodlands." Central Queensland University. Biological and Environmental Sciences, 2007. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20070525.144254.

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This thesis examines the effects of species, rainfall and soil type on tree biomass regressions, as well as the effects of stand dominance and structure on stand biomass regressions in north-east Australian woodlands. This was achieved by examining tree characteristics and biomass relationships for a series of woodland monitoring sites throughout the study area. This study utilised a modified data set from this permanent monitoring site network to provide structural attributes for trees and communities of varying composition in the grazed woodlands. These data were supplemented with environmental data and tree harvest data sets. Initially, the research reported in this thesis developed allometric and stand biomass regressions for Callitris glaucophylla communities. This research also demonstrated that changes in tree-form were not reflected in changes in the environment, nor did such changes reflect changes in tree biomass regressions for three eucalypt species. As a result, a common regression provides a robust estimate of total aboveground biomass of eucalypt trees in the study area. Thus expensive destructive harvesting can generally be avoided for minor eucalypt species. Finally, this study demonstrated a successful methodology that described the stand structure of all the grazed woodland sites based on tree heights. This methodology was developed to allow the expansion of a single stand regression to estimate stand biomass across the entire north-east Australian woodlands. The findings demonstrated in this study, combined with the long-term data from the permanent monitoring network sites, should enhance the estimation of carbon flux within eucalypt communities of north-east Australias grazed woodlands.

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Oliver, Gabriel. "A Wall Building." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/34951.

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This thesis investigates a constructive technique, within the materials and methods of conventional practice, which allows for a common building material such as concrete block to carry form and beauty. Furthermore, this project seeks to demonstrate the role human ingenuity, patience, attention, and perception can continue to play in architecture and construction. The project focuses on an experimental wall type consisting of regular eight inch concrete half-block masonry units, stack-bonded in elevation and subtly transformed in plan to reveal a gradual shift of the exposed faces of the units. A wall was constructed at the Building Research and Demonstration Facility to investigate one example of this wall type.
Master of Architecture

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Souza, Marcos Vinícius de. "Emprego do cloridrato de xilazina, cloridrato de detomidina, e azaperone, em associação a cloridrato de tiletamina, zolazepam, dextrocetamina, cetamina racêmica, diazepam e sulfato de atropina, na contenção de cachorro-do-mato (Cerdocyon thous Linnaeus, 1758), com base em extrapolação alométrica interespecífica." Universidade Federal de Uberlândia, 2017. http://dx.doi.org/10.14393/ufu.te.2018.4.

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O cachorro-do-mato (Cerdocyon thous) é um canídeo neotropical que necessita ser contido por meios farmacológicos para a realização de certos procedimentos médicos e de manejo, em função de características comportamentais de defesa e grande susceptibilidade ao estresse. A combinação de seis protocolos (tiletamina-zolazepam-xilazina-atropina e azaperone; dextrocetamina-diazepam-xilazina-atropina e azaperone; cetamina racêmica-diazepam-xilazina-atropina e azaperone; tiletamina-zolazepam-detomidina-atropina e azaperone; dextrocetamina-diazepam-detomidina-atropina e azaperone; cetamina racêmica-diazepam-detomidina-atropina e azaperone) foram administradas, por via intramuscular, a dez cachorros-do-mato (nove machos e uma fêmea) com pesos médio 5,85 ± 0,83 kg, para possibilitar a realização de procedimentos de que incluíam marcação, exame físico, colheita de amostras de sangue, colheita de medula óssea e outros procedimentos pouco invasivos de moderada duração em Cerdocyon thous de cativeiro. Após a verificação dos pesos de cada cachorro-do-mato, a dose individual de cada uma das drogas foi calculada por meio de extrapolação alométrica interespecífica. O método proposto mostrou-se plenamente adequado à contenção farmacológica de exemplares de Cerdocyon thous que necessitem ser submetidos a procedimentos medianamente dolorosos ou incômodos, como exame físico e colheita de sangue e medula óssea. Não é indicado, porém, para procedimentos cirúrgicos.
The Crab-eating Fox (Cerdocyon thous) is a neotropical carnivorous that requires chemical restraint for handling due to its susceptibility to stress and characteristics of defensive behavior. Ten Crab-eating Fox (9 males and 1 female) weighing 5.85 ± 0.83 kg were given the combination of six protocols (tiletamine-zolazepam-xylazine-atropine and azaperone; dextroketamine-diazepam-xylazine-atropine and azaperone; racemic ketamine-diazepam-xylazine-atropine and azaperone; tiletamine-zolazepam-detomidine-atropine and azaperone; dextroketamina-diazepam-detomidine-atropine and azaperone; racemic ketamine-diazepam-detomidine-atropine and azaperone) by i.m. injection during field procedures that included identification, physical examination, blood sampling, bone marrow harvesting and other mildly invasive procedures of moderate duration in Cerdocyon thous of captivity. After checking the weights of each Crab-eating Fox, the individual dose of each drug was calculated by means of interspecific allometric extrapolation. The proposed method was safe for both the animal and the human personnel and it is recommended for routine management and stressful but not painful medical procedures like physical examination, measuring, sexing, and bone marrow and blood collection in Cerdocyon thous.
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Dissertations / Theses on the topic 'Allometria'

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