Tesi: "Age and growth"

1

Crespo, Cuaresma Jesus, e Tapas Mishra. "Human Capital, Age Structure and Growth Fluctuations". Taylor & Francis, 2011. http://epub.wu.ac.at/3055/1/HCASGFOct07.pdf.

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This article assesses the empirical relationship between per capita income growth fluctuations and the age-structured human capital variations across four groups of geographically clustered developed and developing countries from spatial perspective. We estimate a spatial Vector Autoregressive (VAR) model of income dynamics where the distance between countries is defined on relational space based on their similarity in appropriation tendency of human capital in the production processes. These distances are computed using a newly developed human capital data set which fully characterizes the demographic structure of human capital, and thus underlines the joint relevance of demography and human capital in economic growth. Spatial effects on growth interdependence and complementarity are then explored with respect to the proposed distance metrics. Our results imply that significant cross-country growth interdependence based on human capital distances exists among defined country groups suggesting the need for a cooperative policy programme among them. We also find that the relationship between economic growth and human capital is highly nonlinear as a function of the proposed human capital distance.

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2

Humphrey, Robert R., e Alan B. Humphrey. "Idria columnaris: Age as Determined by Growth Rate". University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/609117.

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3

O'Bryant, Deon. "Mechanisms of Age-Related Prostate Growth and Tumorigenesis". DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2018. http://digitalcommons.auctr.edu/cauetds/138.

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Prostate cancer is the most commonly diagnosed malignancy among men, but few genetic factors that drive prostate cancer initiation have been identified. The WD repeat domain 77 (Wdr77) protein is essential for cellular proliferation when it localizes in the cytoplasm of epithelial cells at the early stage of prostate development. In the adult prostate, it is transported into the nucleus and functions as a co-regulator of the androgen receptor to promote cellular differentiation and prostate function. This developmental process is reversed during prostate tumorigenesis i.e., Wdr77 is translocated from the nucleus into the cytoplasm to drive proliferation of prostate cancer cells. In this study, we used in vivo genetic studies to investigate the role of Wdr77 in prostate tumorigenesis. We found that prostate-specific deletion of Wdr77 abolished prostate tumor initiation induced by loss of the tumor suppressor Pten. Mechanistically, Wdr77 ablation inhibited E2F3 activation and enhanced TGFb signaling, leading to attenuated cellular proliferation induced by loss of Pten. These findings establish an essential role of Wdr77 for prostate tumor initiation.

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4

Allen, Caitlin Shannon. "Firm Size, Age and Growth in South Africa". Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29416.

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The relationship between a firm’s size, age and proportional growth rate is examined using multiple samples of South African firm-level data from the early to mid-2000s. The foundation of this study is Gibrat’s Law of Proportionate Effect (Gibrat, 1931), which states that a firm’s proportional growth rate is independent of its absolute size at the start of a given period. It is assumed that firm growth follows a random walk and, therefore, should not be affected by firm size. An implication of Gibrat’s Law of Proportionate Effect is that the firm size distribution is lognormal. However, based on both empirical and theoretical literature, this theory of firm growth has fallen out of favour and been replaced by the proposal that there is an inverse relationship between a firm’s proportional growth rate and both its size and age. Two questions are evaluated in this research using the samples of South African firms. The first is whether the firm size distribution is lognormal. If this is not the case then Gibrat’s Law of Proportionate Effect can be rejected. However, this approach cannot confirm that Gibrat’s theory is valid and will, therefore, be referred to in this paper as a partial test. It was shown that the log firm size distribution was not normal, but rather right-skewed with a Pareto distribution characterising the upper tail. Consequently, Gibrat’s Law of Proportionate Effect was rejected for the datasets of South African firms. This evidence is largely observational and does not explicitly assess the relationship between proportional growth rates and firm size. Therefore, the second question is whether Gibrat’s Law of Proportionate Effect holds. This was investigated by testing conditions derived from Gibrat’s Law of Proportionate Effect, the results of which can lead to either the rejection or acceptance of this proposition. This study extends Gibrat’s research in order to determine the relationship between firm age and proportional growth. Statistical methods, such as Ordinary Least Squares regressions, considering only firms that survived the period under consideration, were used. The results revealed that Gibrat’s Law of Proportionate Effect was invalid and there was a systematic tendency for the smaller, younger South African firms in the datasets to grow proportionally faster than the larger, older firms. This finding supports the view that firm growth is not entirely random.

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5

Håkansson, Nina. "Population growth : analysis of an age structure population model". Thesis, Linköping University, Department of Mathematics, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-4392.

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This report presents an analysis of a partial differential equation, resulting from population model with age structure. The existence and uniqueness of a solution to the equation are proved. We look at stability of the solution. The asymptotic behaviour of the solution is treated. The report also contains a section about the connection between the solution to the age structure population model and a simple model without age structure.

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6

Cotton, Charles F. "Age, growth, and reproductive biology of deep-water chondrichthyans". W&M ScholarWorks, 2010. https://scholarworks.wm.edu/etd/1539791561.

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Nearly half of the known species of sharks in the world live in the deep sea, yet little is known of the biology or life history of these important predators of the deep. Fishing effort for deep-water sharks, both targeted and incidental, has been increasing worldwide over the last few decades. However, in most cases the impact of this harvest is unknown due to the paucity in landings data and the lack of stock assessments for these species. This research was conducted to provide some of the basic life history information needed to improve the understanding and properly manage deep-water sharks. Specifically, information is presented herein on age determination using dorsal fin spines; the potential for radiometric age validation using dorsal fin spines; the age, growth, and reproductive biology of Squalus mitsukurii from Hawaiian waters; and the reproductive biology and embryonic development of Centrophorus cf. niaukang and Etmopterus princeps.;Dorsal fin spines offer an alternate structure for age determination in phalacanthous chondrichthyans. In this study, I sought to identify optimal methods of age determination using dorsal fin spines of 14 species of squaliform sharks and two species of holocephalans. Growth bands can be found in three zones of the fin spine: on the enamel cap (if present), at the base of the whole spine, or in the inner dentine layer. Each of these three methods was applied to fin spines from these 16 species. Results of each method are compared and discussed, with an optimal aging method suggested for each species.;Radiometric methods have been used to validate age estimates from teleost otoliths, shark vertebrae, and coral skeletons. The radioisotopes 210Pb and 226Ra were ineffective for age determination of dorsal fin spines, possibly due to a violation of the assumption of constant isotopic uptake, or conversely the spine may not act as a closed system.;A study of age, growth and reproductive biology of Squalus mitsukurii was conducted near Oahu, Hawaii. Age estimates ranged from 3 to 26 years for females and 6 to 23 years for males. Growth parameters estimated with multiple growth models indicated that this a K-selected species, characterized by high longevity, late maturity, and slow growth. Observed fecundity also indicated that reproductive output is low for this species.;A study of embryonic development in Centrophorus cf. niaukang and Etmopterus princeps indicated that the process of embryogenesis results in a range in organic matter depletion from the time of fertilization to parturition. Centrophorus cf. niaukang embryos showed a reduction of 19.5% in organic matter, while E. princeps embryos showed a reduction of 7.8% in organic matter over the course of embryonic development. These results indicate that at least one of these species may be matrotrophic. Observed fecundity and maturity ogives are also presented for each species.;This study on age determination, growth, and reproductive biology of several species of deep-water sharks and holocephalans indicated that these are K-selected species. Future harvest of these species should proceed with caution, as they are prone to overexploitation and localized depletion.

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7

Crespo, Cuaresma Jesus, C. Samir K e Petra Sauer. "Age-Specific Education Inequality, Education Mobility and Income Growth". European Commission, bmwfw, 2013. http://epub.wu.ac.at/4716/1/WWWforEurope_WPS_no006_MS15.pdf.

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We construct a new dataset of inequality in educational attainment by age and sex at the global level. The comparison of education inequality measures across age groups allows us to assess the effect of inter-generational education attainment trends on economic growth. Our results indicate that countries which are able to reduce the inequality of educational attainment of young cohorts over time tend to have higher growth rates of income per capita. This effect is additional to that implied by the accumulation of human capital and implies that policies aiming at providing broad-based access to schooling have returns in terms of economic growth that go beyond those achieved by increasing average educational attainment.
Series: WWWforEurope

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8

Lang, Judy Brenda. "The growth characteristics of sparid otoliths". Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005129.

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The periodicity of formation of growth increments in the otoliths of South African sparids was validated by the oxytetracycline labelling technique. Intramuscular injections of oxytetracycline at a dosage of 250mg/kg marked the otoliths of laboratory held juvenile sparids, while a dosage range of 50 - 100mg/kg oxytetracycline, injected intramuscularly, marked adult sparids in the field. Laboratory held, larval sparid otoliths were marked by immersion for 24hrs a solution of 100-150mg/l alizarin complexone. Both daily (microstructural) and annual (macrostructural) growth increments were identified in the otoliths. The micro incremental pattern of deposition in the sparid otoliths conformed to the general pattern of otolith structure. Sparid otoliths consisted of a central opaque nucleus composed of multiple primordia. surrounding this nucleus were daily increments which decreased in width as the distance from the nucleus increased. Both check rings and subdaily increments were visible throughout the otolith. Minor environmental changes did not affect micro incremental deposition. Narrow opaque and wide hyaline annual growth zones were identified in sectioned sparid otoliths. Scanning electron microscope analysis of the annual growth zones revealed that microincrements within the opaque zone were narrowly spaced with prominent discontinuous phases. This resulted in the greater optical density and higher protein content of the zone. The hyaline zone was composed of widely spaced daily increments with prominent incremental phases accounting for the translucent nature of this zone. Opaque zone formation in the otoliths of many South African sparids was found to occur primarily during periods of reproductive activity and was shown to be indicative of slow otolith growth. The hyaline zone was formed after the spawning season, representative of fast otolith growth. The results of this study have resolved much of the controversy surrounding the rate of growth and time of formation of the opaque and hyaline growth zones in South African sparid otoliths.

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9

Crespo, Cuaresma Jesus, Martin Lábaj e Patrik Pruzinský. "Prospective Ageing and Economic Growth in Europe". WU Vienna University of Economics and Business, 2014. http://epub.wu.ac.at/4080/1/wp165.pdf.

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We assess empirically the role played by prospective ageing measures as a predictor of income growth in Europe. We show that prospective ageing measures which move beyond chronological age and incorporate changes in life expectancy are able to explain better the recent long-run growth experience of European economies. The improvement in explanatory power of prospective ageing indicators as compared to standard measures based on chronological age is particularly relevant for long-run economic growth horizons. (authors' abstract)
Series: Department of Economics Working Paper Series

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10

Kebede, Endale Birhanu, Wolfgang Lutz, Cuaresma Jesus Crespo e Alexia Fürnkranz-Prskawetz. "Education rather than age structure brings demographic dividend". The National Academies of Sciences, Engineering, and Medicine, 2019. http://dx.doi.org/10.1073/pnas.1820362116.

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The relationship between population changes and economic growth has been debated since Malthus. Initially focusing on population growth, the notion of demographic dividend has shifted the attention to changes in age structures with an assumed window of opportunity that opens when falling birth rates lead to a relatively higher proportion of the working-age population. This has become the dominant paradigm in the field of population and development, and an advocacy tool for highlighting the benefits of family planning and fertility decline. While this view acknowledges that the dividend can only be realized if associated with investments in human capital, its causal trigger is still seen in exogenous fertility decline. In contrast, unified growth theory has established human capital as a trigger of both demographic transition and economic growth. We assess the relative importance of changing age structure and increasing human capital for economic growth for a panel of 165 countries during the time period of 1980-2015. The results show a clear dominance of improving education over age structure and give evidence that the demographic dividend is driven by human capital. Declining youth dependency ratios even show negative impacts on income growth when combined with low education. Based on a multidimensional understanding of demography that considers education in addition to age, and with a view to the additional effects of education on health and general resilience, we conclude that the true demographic dividend is a human capital dividend. Global population policies should thus focus on strengthening the human resource base for sustainable development.

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11

Lutz, Wolfgang, Cuaresma Jesus Crespo, Endale Birhanu Kebede, Alexia Fürnkranz-Prskawetz, Warren Sanderson e Erich Striessnig. "Education rather than age structure brings demographic dividend". The National Academies of Sciences, Engineering, and Medicine, 2019. http://dx.doi.org/10.1073/pnas.1820362116.

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Abstract (sommario):

The relationship between population changes and economic growth has been debated since Malthus. Initially focusing on population growth, the notion of demographic dividend has shifted the attention to changes in age structures with an assumed window of opportunity that opens when falling birth rates lead to a relatively higher proportion of the working-age population. This has become the dominant paradigm in the field of population and development, and an advocacy tool for highlighting the benefits of family planning and fertility decline. While this view acknowledges that the dividend can only be realized if associated with investments in human capital, its causal trigger is still seen in exogenous fertility decline. In contrast, unified growth theory has established human capital as a trigger of both demographic transition and economic growth. We assess the relative importance of changing age structure and increasing human capital for economic growth for a panel of 165 countries during the time period of 1980-2015. The results show a clear dominance of improving education over age structure and give evidence that the demographic dividend is driven by human capital. Declining youth dependency ratios even show negative impacts on income growth when combined with low education. Based on a multidimensional understanding of demography that considers education in addition to age, and with a view to the additional effects of education on health and general resilience, we conclude that the true demographic dividend is a human capital dividend. Global population policies should thus focus on strengthening the human resource base for sustainable development.

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12

Towne, Ian A. "Age and Growth of Hogfish (Lachnolaimus maximus) in Southeast Florida". Thesis, NSUWorks, 2018. https://nsuworks.nova.edu/occ_stuetd/465.

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Hogfish (Lachnolaimus maximus; Walbaum 1792) from Southeast Florida were aged using sectioned otoliths and growth rates were calculated using the von Bertalanffy growth equation. The samples were collected from Broward County (n=209); other regions of Southeast Florida (n=18), the Florida Keys (n=35) and Bahamas (n=43). Growth rates were determined for each of these areas and were then compared to previously reported growth rates from other regions including the eastern Gulf of Mexico and Florida Keys. There was significant separation at the 95% confidence level between growth rates from each reagion. The average maximum fork length increased, from the Florida Keys (336mm) to Southeast Florida (414-mm) by 78-mm. However, the annual survival rate was the same (S=61%) between these two regions and the maximum age of Southeast Florida (age 12) was still half that of the previously reported eastern Gulf (age 23). Broward County was divided into three reef zones each at different depths (5-m, 10-m, and 20-m) and growth rate and survival rate were compared between zones. Results showed a decrease in maximum fork length with reef depth (857-mm, 420-mm, 352-mm), as well as an increase in mean age (age 3, 4, 5), maximum age (9, 10, 12), and survival (42%, 65%, 73%), respectively. The decrease in observed growth rate of an area as a whole (e.g. Florida Keys) may represent an example of Lee’s phenomena caused by increased top-down selective fishing pressure. However, the growth rates of individual hogfish are most likely a result of differences in habitat and food resource availability. This study provides baseline age and growth information for hogfish in Southeast Florida prior to the recent changes to the fishery regulations, which will help fisheries management better understand the effects of alternative management strategies.

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13

Davenport, Sarah E. "Potential Causes of Extrauterine Growth Failure in Premature Infants Born Appropriate for Gestational Age". eScholarship@UMMS, 2021. https://escholarship.umassmed.edu/gsbs_diss/1137.

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Background: Extrauterine growth restriction (EUGR) is multifactorial in etiology and predisposes infants to multiple morbidities that can be significantly ameliorated by adequate nutrition and appropriate longitudinal growth. Current strategies to reduce the risk of EUGR include optimization of parental nutrition, varying schedules of feeding advances, and caloric supplementation. Very low birthweight (VLBW) preterm infants are particularly affected by EUGR, therefore ensuring adequate postnatal growth is an essential component in improving the long-term health outcomes for VLBW infants. The objectives of this observational study were to examine potential risk factors for growth failure among premature infants that did not respond to caloric and volume supplementation. Methods: We conducted a retrospective chart review of all infants born at the University of Massachusetts level III NICU from January 2016 to June 2020. Growth was tracked using PediTools electronic gestational age and growth calculators. (17) We reviewed the EMRs of infants who met the criteria for EUGR at the time of hospital discharge for a variety of potential factors affecting growth. Results: Overall, a total of 448 infants were screened with a final study cohort of 358 infants, of which 13% were discharge with EUGR. Analysis of demographic and clinical characteristics of infants with EUGR before and after nutritional intervention showed no statistically significant differences between the two cohorts. Pre-protocol, only weight percentiles and z-scores were statistically significant. Post-protocol, the change in z-score was also statistically significant. The only factor found to be statistically significantly different between was Necrotizing enterocolitis (NEC). Timing of EUGR in the pre-protocol groups occurred between 33-35 weeks, while in the post-protocol group EUGR occurred between 32 and 37 weeks (Figure 2). Conclusions: Our findings confirmed the presence of several factors that have been previously shown to increase risk for EUGR, including male sex, lower gestational age, lower birth weight, and the occurrence of NEC. It also identified an additional risk factor, that of being born “constitutionally small”. In the post-protocol cohort, the change in z-score was statistically significant in addition to birth weight percentile and z-score and discharge weight percentile in z-score. The window in which EUGR occurred as well as the interquartile range was significantly widened post-protocol. These data suggest that the volume supplementation protocol successfully addressed the causes of EUGR in some infants, but other mechanisms may have occurred in infants who were still discharged with EUGR post-protocol.

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14

Sayer, Avan Aihie. "Aging and its relationship to early growth". Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242108.

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15

Carman, Laurie Susanna. "Regenerative growth of axons of hamster optic tract : effects of age, substrate, and growth-promoting factors". Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/13989.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Brain and Cognitive Sciences, 1989.
Title as it appears in the M.I.T. Graduate List, Sept. 1989: Regenerative growth of hamster optic tract axons.
Includes bibliographical references (leaves 93-117).
by Laurie Susanna Carman.
Ph.D.

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16

Ogbagaber, Semhar. "A NUMERICAL METHOD FOR ESTIMATING THE VARIANCE OF AGE AT MAXIMUM GROWTH RATE IN GROWTH MODELS". VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/94.

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Most studies on maturation and body composition using the Fels Longitudinal data mention peak height velocity (PHV) as an important outcome measure. The PHV is often derived from growth models such as the triple logistic model fitted to the stature (height) data. The age at PHV is sometimes ordinalized to designate an individual as an early, average or late maturer. In theory, age at PHV is the age at which the rate of growth reaches the maximum. Theoretically, for a well behaved growth function, this could be obtained by setting the second derivative of the growth function to zero and solving for age. Such a solution would obviously depend on the parameters of the growth function. An estimate of the age at PHV would be a function of estimates of these parameters. Since the estimates of age at PHV are ultimately used as a predictor variable for analyzing adulthood outcomes, the uncertainty in the estimation of the PHV inherent due to the uncertainty in the estimation of the growth model need to be accounted for. The asymptotic s.e. of the age at maximum velocity in simple growth models such as the logistic and the Gompertz models could be explicitly obtained because explicit formulas for the age at maximum velocity are available. In this thesis a numerical method is proposed for computing the s.e. of the age at PHV for those that do not lead to explicit solutions for the age at PHV. The accuracy of this method is demonstrated by computing the s.e. using the explicit method as well as the proposed numerical methods and by comparing them. Incorporating the estimates of the s.e. in regression models that use age at PHV as predictor is illustrated using the FELS data.

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17

Nieman, Mark David. "In search of growth neoliberal and institutional models for economic growth in an age of globalization /". [Ames, Iowa : Iowa State University], 2008.

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18

Lundgren, Maria. "Born Small for Gestational Age : Impact of Linear Catch-up Growth". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl.[distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3563.

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19

Horta, Bernardo Lessa. "Determinants of catch-up growth in small-for-gestational age infants". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38067.

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Abstract (sommario):

Objective. To identify predictors of catch-up growth during the first year of life among small for gestational age (SGA) infants in a developing country setting.
Design. Cohort study, with follow-up visits at 1, 3, 6 and 12 months.
Setting. Pelotas, a southern Brazilian city.
Population. SGA infants who were born in 1993 and whose families lived in the urban area of Pelotas.
Main outcomes. Weight and length gain from birth to 6 months and from 6 to 12 months.
Results. Two hundred twenty term SGA infants were targeted for follow-up, which was achieved for 205 (93.2%) infants at 12 months. At 6 months, the proportion of infants with weight-for-age and length-for-age z-scores <-1.28 SDS was 18.9% and 37.8%, respectively. At 12 months, the proportion of children with a weight-for-age z-score <-1.28 SDS increased to 35.2%, whereas for length-for-age this proportion remained about the same as it had been at 6 months. Severity of intrauterine growth retardation, body proportionality at birth, maternal remunerated work after delivery, maternal age, parity, maternal prepregnancy body mass index and maternal smoking during pregnancy had no significant effect on postnatal growth in the first year of life. Those infants who were weaned by 1 month had faster weight and length gain by 6 months. Socioeconomic status (SES) modified the effect of breast feeding duration on weight and length gain in the first 6 months of life. Among high-SES families, those children who were weaned by 1 month gained 578 g more than those still breast feeding at 6 months. Among low-SES families, however, those children who were weaned by 1 month gained 349 g less than those still breast feeding at 6 months. Those children who were weaned by 6 months had faster weight gain from 6 to 12 months, and this association was not modified by SES, while low SES was associated with slower weight and length gain in the same period. Children of short (<150 cm) mothers gained 1.31 cm less (95% confidence interval -2.52 to -0.1) by 6 months than those of mothers >160 cm. Children who were hospitalized showed a nonsignificantly slower length gain throughout the first year of life.
Conclusion. SGA infants experienced catch-up growth for weight and length but remained shorter and lighter than those in the NCHS reference population at both 6 and 12 months of age. Socioeconomic status and infant feeding were the main determinants of catch-up growth.

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20

Provost, Cameron Murray. "Age, growth, and sexual maturity of the deepsea skate, Bathyraja abyssicola". Thesis, Alaska Pacific University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10104548.

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Research into the age, growth, and reproductive characteristics of chondrichthyan fishes has increased substantially over the past couple of decades. This study set out to estimate age deepsea skate, Bathyraja abyssicola using vertebral centra and caudal thorns, estimate length at age, and determine length at maturity. Sixty-three specimens of B. abyssicola (n=29 males; n=34 females) were taken on National Marine Fisheries Service bottom trawl surveys between 2001 and 2012. Information derived and structures collected from these samples included sex, maturity class, total length, caudal thorns and, vertebrae. Ageing methods attempted include histology and gross sectioning (vertebral centra) and surface staining (caudal thorns). Moderate success with centra sectioned using the histological method allowed some inference to be made into life history characteristics. Deepsea skates appear to have slow average growth (26 mm yr^-1 ±5.41, 95% c.i.) and mature at a large size (males: TL₅₀ = 1175.4 mm, females: TL₅₀ = 1267.3 mm). Band pair counts were not validated as true ages. Males from which growth bands could be enumerated were smaller (n = 10, x¯ = 718 mm, SD = 209 mm) on average than that for females (n = 7, x¯=990 mm, SD = 319 mm). This study provides the first attempt to assess abyssicola age, growth rate, and sexual maturity traits; information needed for informed skate management.

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21

Woodland, Ryan J. "Age, growth and recruitment of Hudson River shortnose sturgeon (Acipenser brevirostrum)". College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2984.

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Abstract (sommario):

Thesis (M.S.) -- University of Maryland, College Park, 2005.
Thesis research directed by: Marine, Estuarine, Environmental Sciences Graduate Program. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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22

Klinger, Ruth Ellen. "Age and Growth of Juvenile Loggerheads (Caretta caretta), from Chesapeake Bay". W&M ScholarWorks, 1988. https://scholarworks.wm.edu/etd/1539617582.

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23

au, bwise@fish wa gov, e Brent Stephen Wise. "Age composition and growth rates of selected fish species in Western Australia". Murdoch University, 2005. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20061123.120638.

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Abstract (sommario):

Growth typically varies considerably amongst the individuals in a population and between individuals in different populations of the same species, especially when those populations are found in environments in which the characteristics differ markedly. Although the annuli in hard structures are often used to age fish, such growth zones are not always clearly defined in these structures. Thus, in these cases, it is necessary to use alternative methods for ageing, such as analysis of modal progressions in length-frequency data. However, these types of techniques can usually only identify distinct size classes that correspond to an age class. They thus only enable an individual fish to be aged when it is a member of a discrete size cohort. Such a situation generally only applies to the younger age classes. This thesis reports the results of studies on a species that can be aged using the annuli in one of its hard parts (asteriscus otoliths), i.e. Cnidoglanis macrocephalus, and four species (Amniataba caudavitatta, Apogon rueppellii, Pseudogobius olorum and Favionigobius lateralis) for which it was necessary to use a method such as length-frequency analysis for ageing. Cnidoglanis macrocephalus is an important recreational and commercial species caught in coastal marine and estuarine environments in south-western Australia. However, all previous detailed studies on the age and growth on this species have focused on estuarine populations. This thesis reports the results of a study of the biology of C. macrocephalus in Princess Royal Harbour, a marine embayment on the south coast of Western Australia. Samples of C. macrocephalus were collected from amongst the macroalgae that were removed from this highly eutrophic embayment by mechanical harvesters. Analysis of the reproductive and size composition data derived from these catches showed that spawning occurs between October and December and that fecundity ranged from 75 in a 384 mm fish to 465 in a 443 mm fish. Small fish (<200 mm) were rarely caught, reflecting the fact that the young of this species are difficult to capture. Analysis of the trends exhibited by the marginal increments on otoliths showed that the number of annuli on this hard structure could be used to age C. macrocephalus. The samples of C. macrocephalus collected from Princess Royal Harbour contained female and male fish that had lived for up to 10 and 9 years in age and reached maximum lengths and weights of 523 mm and 745.3 g and 557 mm and 735.8 g, respectively. To overcome the paucity of small fish, von Bertalanffy growth curves were constructed using back-calculated lengths and employing the scale proportional hypothesis and body proportional hypothesis (see Francis 1990). The growth rates of females and males were slower than those in a nearby seasonally closed estuary (Wilson Inlet) and in a permanently open estuary on the lower west coast of Australia (Swan River Estuary). Yield per recruit analyses were conducted in order to ascertain what minimum legal lengths were appropriate for the capture of C. macrocephalus in Princess Royal Harbour, the Swan River Estuary and Wilson Inlet in order to sustain the stocks in those water bodies. The age and growth of Amniataba caudavittata and Apogon rueppellii in the Swan River Estuary were determined by analysing the trends exhibited by modes in sequential monthly length-frequency data. This was achieved by employing MULTIFAN, which constrained the means of the lengths of the cohorts in successive monthly samples to a seasonal form of the von Bertalanffy growth curve. The resulting growth parameters derived by MULTIFAN were similar to those derived from the growth curves fitted to the means of the cohorts determined independently for each monthly sample by MIX. The discreteness of the distributions and modes of size classes in length-frequency data for A. caudavittata and A. rueppellii enabled sound growth curves to be constructed for both of these species. The growth curves of these two sexes of both species were significantly different, with K being lower and L being higher for females. The trends exhibited by these growth curves emphasised that the growth of both species is highly seasonal, with little or no increase in length occurring during the cooler part of the year. The seasonal von Bertalanffy growth equations implied that negative growth occurred in winter, but this is an artefact produced by size-related differences in offshore movements that occur at that time of the year. The age and growth of two further species from the Swan River Estuary, Pseudogobius olorum and Favonigobius lateralis, were also studied. Since P. olorum and F. lateralis both spawn at different times of the year and these times (spring and autumn) are not regularly spaced during the year, they produce new 0+ recruits at two irregularly-spaced times of the year. Consequently, MUTLIFAN cannot be used to analyse the size-distribution data for these two gobiid species. Thus, MIX was used to identify the size classes present in sequential samples and to provide means for the length distributions of those size classes. von Bertalanffy growth equations were then fitted to the mean lengths at the inferred age of the males and females of each size class of each species. It was found appropriate to use the traditional von Bertalanffy growth curve for describing the growth of the product of the spring-spawning group of both species and a seasonal von Bertalanffy growth curve for that of the product of the autumn-spawning groups of both species. The growth curves, when considered in conjunction with the trends exhibited by reproductive variables, demonstrate that female F. lateralis attains sexual maturity more rapidly and at a larger size than P. olorum. The majority of the female and male progeny of the summer and autumn-spawning groups of F. lateralis reach maturity when they are approximately 3½ and 8½ months old, respectively, compared with five and seven months old, respectively, for P. olorum. Models, incorporating data on water temperature and salinity and the growth and reproduction characteristics of P. olorum and F. lateralis, were used to postulate how environmental factors might be regulating when these two gobiid species spawn. The results of these models support the conclusion that the bimodal timing of spawning of P. olorum in the upper estuary was regulated by water temperature, with spawning occurring between 20 and 25oC but inhibited by temperatures greater than 25oC. They also showed that, although water temperature also influenced the timing of spawning of F. lateralis in the lower estuary, the onset of spawning by this species only occurred when salinities had reached 300/00.

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24

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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25

Trott, Tammy Marlena. "Age, growth and reproductive biology of the coney, cephalopholis fulva, in Bermuda". Thesis, University of Liverpool, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443922.

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26

Wise, Brent Stephen. "Age composition and growth rates of selected fish species in Western Australia". Thesis, Wise, Brent Stephen (2005) Age composition and growth rates of selected fish species in Western Australia. PhD thesis, Murdoch University, 2005. https://researchrepository.murdoch.edu.au/id/eprint/410/.

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Abstract (sommario):

Growth typically varies considerably amongst the individuals in a population and between individuals in different populations of the same species, especially when those populations are found in environments in which the characteristics differ markedly. Although the annuli in hard structures are often used to age fish, such growth zones are not always clearly defined in these structures. Thus, in these cases, it is necessary to use alternative methods for ageing, such as analysis of modal progressions in length-frequency data. However, these types of techniques can usually only identify distinct size classes that correspond to an age class. They thus only enable an individual fish to be aged when it is a member of a discrete size cohort. Such a situation generally only applies to the younger age classes. This thesis reports the results of studies on a species that can be aged using the annuli in one of its hard parts (asteriscus otoliths), i.e. Cnidoglanis macrocephalus, and four species (Amniataba caudavitatta, Apogon rueppellii, Pseudogobius olorum and Favionigobius lateralis) for which it was necessary to use a method such as length-frequency analysis for ageing. Cnidoglanis macrocephalus is an important recreational and commercial species caught in coastal marine and estuarine environments in south-western Australia. However, all previous detailed studies on the age and growth on this species have focused on estuarine populations. This thesis reports the results of a study of the biology of C. macrocephalus in Princess Royal Harbour, a marine embayment on the south coast of Western Australia. Samples of C. macrocephalus were collected from amongst the macroalgae that were removed from this highly eutrophic embayment by mechanical harvesters. Analysis of the reproductive and size composition data derived from these catches showed that spawning occurs between October and December and that fecundity ranged from 75 in a 384 mm fish to 465 in a 443 mm fish. Small fish (<200 mm) were rarely caught, reflecting the fact that the young of this species are difficult to capture. Analysis of the trends exhibited by the marginal increments on otoliths showed that the number of annuli on this hard structure could be used to age C. macrocephalus. The samples of C. macrocephalus collected from Princess Royal Harbour contained female and male fish that had lived for up to 10 and 9 years in age and reached maximum lengths and weights of 523 mm and 745.3 g and 557 mm and 735.8 g, respectively. To overcome the paucity of small fish, von Bertalanffy growth curves were constructed using back-calculated lengths and employing the scale proportional hypothesis and body proportional hypothesis (see Francis 1990). The growth rates of females and males were slower than those in a nearby seasonally closed estuary (Wilson Inlet) and in a permanently open estuary on the lower west coast of Australia (Swan River Estuary). Yield per recruit analyses were conducted in order to ascertain what minimum legal lengths were appropriate for the capture of C. macrocephalus in Princess Royal Harbour, the Swan River Estuary and Wilson Inlet in order to sustain the stocks in those water bodies. The age and growth of Amniataba caudavittata and Apogon rueppellii in the Swan River Estuary were determined by analysing the trends exhibited by modes in sequential monthly length-frequency data. This was achieved by employing MULTIFAN, which constrained the means of the lengths of the cohorts in successive monthly samples to a seasonal form of the von Bertalanffy growth curve. The resulting growth parameters derived by MULTIFAN were similar to those derived from the growth curves fitted to the means of the cohorts determined independently for each monthly sample by MIX. The discreteness of the distributions and modes of size classes in length-frequency data for A. caudavittata and A. rueppellii enabled sound growth curves to be constructed for both of these species. The growth curves of these two sexes of both species were significantly different, with K being lower and L being higher for females. The trends exhibited by these growth curves emphasised that the growth of both species is highly seasonal, with little or no increase in length occurring during the cooler part of the year. The seasonal von Bertalanffy growth equations implied that 'negative growth' occurred in winter, but this is an artefact produced by size-related differences in offshore movements that occur at that time of the year. The age and growth of two further species from the Swan River Estuary, Pseudogobius olorum and Favonigobius lateralis, were also studied. Since P. olorum and F. lateralis both spawn at different times of the year and these times (spring and autumn) are not regularly spaced during the year, they produce new 0+ recruits at two irregularly-spaced times of the year. Consequently, MUTLIFAN cannot be used to analyse the size-distribution data for these two gobiid species. Thus, MIX was used to identify the size classes present in sequential samples and to provide means for the length distributions of those size classes. von Bertalanffy growth equations were then fitted to the mean lengths at the inferred age of the males and females of each size class of each species. It was found appropriate to use the traditional von Bertalanffy growth curve for describing the growth of the product of the spring-spawning group of both species and a seasonal von Bertalanffy growth curve for that of the product of the autumn-spawning groups of both species. The growth curves, when considered in conjunction with the trends exhibited by reproductive variables, demonstrate that female F. lateralis attains sexual maturity more rapidly and at a larger size than P. olorum. The majority of the female and male progeny of the summer and autumn-spawning groups of F. lateralis reach maturity when they are approximately 3 1/2 and 8 1/2 months old, respectively, compared with five and seven months old, respectively, for P. olorum. Models, incorporating data on water temperature and salinity and the growth and reproduction characteristics of P. olorum and F. lateralis, were used to postulate how environmental factors might be regulating when these two gobiid species spawn. The results of these models support the conclusion that the bimodal timing of spawning of P. olorum in the upper estuary was regulated by water temperature, with spawning occurring between 20 and 25oC but inhibited by temperatures greater than 25oC. They also showed that, although water temperature also influenced the timing of spawning of F. lateralis in the lower estuary, the onset of spawning by this species only occurred when salinities had reached 300/00.

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27

Wise, Brent Stephen. "Age composition and growth rates of selected fish species in Western Australia". Wise, Brent Stephen (2005) Age composition and growth rates of selected fish species in Western Australia. PhD thesis, Murdoch University, 2005. http://researchrepository.murdoch.edu.au/410/.

Testo completo

Abstract (sommario):

Growth typically varies considerably amongst the individuals in a population and between individuals in different populations of the same species, especially when those populations are found in environments in which the characteristics differ markedly. Although the annuli in hard structures are often used to age fish, such growth zones are not always clearly defined in these structures. Thus, in these cases, it is necessary to use alternative methods for ageing, such as analysis of modal progressions in length-frequency data. However, these types of techniques can usually only identify distinct size classes that correspond to an age class. They thus only enable an individual fish to be aged when it is a member of a discrete size cohort. Such a situation generally only applies to the younger age classes. This thesis reports the results of studies on a species that can be aged using the annuli in one of its hard parts (asteriscus otoliths), i.e. Cnidoglanis macrocephalus, and four species (Amniataba caudavitatta, Apogon rueppellii, Pseudogobius olorum and Favionigobius lateralis) for which it was necessary to use a method such as length-frequency analysis for ageing. Cnidoglanis macrocephalus is an important recreational and commercial species caught in coastal marine and estuarine environments in south-western Australia. However, all previous detailed studies on the age and growth on this species have focused on estuarine populations. This thesis reports the results of a study of the biology of C. macrocephalus in Princess Royal Harbour, a marine embayment on the south coast of Western Australia. Samples of C. macrocephalus were collected from amongst the macroalgae that were removed from this highly eutrophic embayment by mechanical harvesters. Analysis of the reproductive and size composition data derived from these catches showed that spawning occurs between October and December and that fecundity ranged from 75 in a 384 mm fish to 465 in a 443 mm fish. Small fish (<200 mm) were rarely caught, reflecting the fact that the young of this species are difficult to capture. Analysis of the trends exhibited by the marginal increments on otoliths showed that the number of annuli on this hard structure could be used to age C. macrocephalus. The samples of C. macrocephalus collected from Princess Royal Harbour contained female and male fish that had lived for up to 10 and 9 years in age and reached maximum lengths and weights of 523 mm and 745.3 g and 557 mm and 735.8 g, respectively. To overcome the paucity of small fish, von Bertalanffy growth curves were constructed using back-calculated lengths and employing the scale proportional hypothesis and body proportional hypothesis (see Francis 1990). The growth rates of females and males were slower than those in a nearby seasonally closed estuary (Wilson Inlet) and in a permanently open estuary on the lower west coast of Australia (Swan River Estuary). Yield per recruit analyses were conducted in order to ascertain what minimum legal lengths were appropriate for the capture of C. macrocephalus in Princess Royal Harbour, the Swan River Estuary and Wilson Inlet in order to sustain the stocks in those water bodies. The age and growth of Amniataba caudavittata and Apogon rueppellii in the Swan River Estuary were determined by analysing the trends exhibited by modes in sequential monthly length-frequency data. This was achieved by employing MULTIFAN, which constrained the means of the lengths of the cohorts in successive monthly samples to a seasonal form of the von Bertalanffy growth curve. The resulting growth parameters derived by MULTIFAN were similar to those derived from the growth curves fitted to the means of the cohorts determined independently for each monthly sample by MIX. The discreteness of the distributions and modes of size classes in length-frequency data for A. caudavittata and A. rueppellii enabled sound growth curves to be constructed for both of these species. The growth curves of these two sexes of both species were significantly different, with K being lower and L being higher for females. The trends exhibited by these growth curves emphasised that the growth of both species is highly seasonal, with little or no increase in length occurring during the cooler part of the year. The seasonal von Bertalanffy growth equations implied that 'negative growth' occurred in winter, but this is an artefact produced by size-related differences in offshore movements that occur at that time of the year. The age and growth of two further species from the Swan River Estuary, Pseudogobius olorum and Favonigobius lateralis, were also studied. Since P. olorum and F. lateralis both spawn at different times of the year and these times (spring and autumn) are not regularly spaced during the year, they produce new 0+ recruits at two irregularly-spaced times of the year. Consequently, MUTLIFAN cannot be used to analyse the size-distribution data for these two gobiid species. Thus, MIX was used to identify the size classes present in sequential samples and to provide means for the length distributions of those size classes. von Bertalanffy growth equations were then fitted to the mean lengths at the inferred age of the males and females of each size class of each species. It was found appropriate to use the traditional von Bertalanffy growth curve for describing the growth of the product of the spring-spawning group of both species and a seasonal von Bertalanffy growth curve for that of the product of the autumn-spawning groups of both species. The growth curves, when considered in conjunction with the trends exhibited by reproductive variables, demonstrate that female F. lateralis attains sexual maturity more rapidly and at a larger size than P. olorum. The majority of the female and male progeny of the summer and autumn-spawning groups of F. lateralis reach maturity when they are approximately 3 1/2 and 8 1/2 months old, respectively, compared with five and seven months old, respectively, for P. olorum. Models, incorporating data on water temperature and salinity and the growth and reproduction characteristics of P. olorum and F. lateralis, were used to postulate how environmental factors might be regulating when these two gobiid species spawn. The results of these models support the conclusion that the bimodal timing of spawning of P. olorum in the upper estuary was regulated by water temperature, with spawning occurring between 20 and 25oC but inhibited by temperatures greater than 25oC. They also showed that, although water temperature also influenced the timing of spawning of F. lateralis in the lower estuary, the onset of spawning by this species only occurred when salinities had reached 300/00.

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28

Lee, Chung-yung Jetty, e 李忠英. "The quality of pig meat in relation to sex and slaughtering age". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31213297.

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29

Lean, Samantha. "Advanced maternal age : identifying mechanisms underlying vulnerability to stillbirth". Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/advanced-maternal-age-identifying-mechanisms-underlying-vulnerability-to-stillbirth(c884a509-287f-4543-aad4-c8ff860d3715).html.

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Abstract (sommario):

Advanced maternal age (AMA) is defined as childbearing in mothers ≥35 years of age and is becoming increasingly prevalent in high income countries. AMA has been associated with increased risk of adverse pregnancy outcomes, particularly stillbirth. Although AMA mothers have higher rates of chromosomal abnormalities and maternal co-morbidities, AMA remains an independent risk factor for stillbirth. Despite these findings, the etiology behind this increased risk is unknown. We hypothesise that an altered maternal environment, including increased oxidative stress and inflammation, due to ageing causes placental dysfunction which increases AMA mothers’ vulnerability to stillbirth. A holistic approach was applied to investigate placental dysfunction in AMA. Firstly, a systematic review and meta-analysis comprehensively reviewed existing data on AMA and associated adverse pregnancy outcomes. Secondly, Manchester Advanced Maternal Age Study (MAMAS), a multi-centre prospective observational cohort study, was conducted to investigate risk factors for composite adverse pregnancy outcome (CAPO) in AMA. MAMAS utilised both uni- and multivariate analysis on demographic and clinical data, and measuring biomarkers of ageing and placental dysfunction by ELISA in maternal circulation during the third trimester of pregnancy. Utero-placental dysfunction was directly investigated in uncomplicated AMA pregnancies by quantifying placental morphology, placental nutrient transport capabilities and both placental and maternal uterine vascular responses. Finally, a C57BL/6J murine model of AMA was developed and characterised to further investigate maternal age on pregnancy outcome and the role of the placenta. In the meta-analysis, maternal age was linearly associated with increased risk of stillbirth and other adverse outcomes strongly associated with placental dysfunction (fetal growth restriction, preeclampsia and placental abruption). In MAMAS, smoking status and primiparity were predictive of CAPO. After adjustment, AMA mothers had an odd ratio of 2.05-3.43 of CAPO compared to 20-30 year old mothers. AMA mothers showed evidence of increased oxidative stress and pro-inflammatory bias. AMA mothers who suffered CAPO showed reduced placental endocrine capacity seen in placental dysfunction. Placentas from uneventful AMA pregnancies showed evidence of accelerated ageing and placental adaptation with increased nutrient transport, increased placental weight but reduced efficiency, and altered vascular function. AMA mice showed many similar aspects to human AMA with increased fetal loss, fetal growth restriction and increased placental size. These studies provide robust evidence for increased incidence of adverse pregnancy outcome due to placental dysfunction in pregnancies of women of AMA. This finding requires the appropriate recognition in a clinical context, with a greater focus on personalised obstetric care in an attempt to reduce stillbirth rates in this high risk population. By optimising antenatal and obstetric care for AMA mothers, we could reduce stillbirth rates by 4.7% - the population attributable risk due to AMA. These studies highlight key areas of future research that will further understanding into stillbirth risk in AMA pregnancy, test predictive models and test therapies and clinical care interventions an ultimately improve pregnancy outcome in mothers of AMA.

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30

Yang, Junping, e 楊俊平. "Brain development in Chinese: effects of age,IQ and reading experience". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B3792932X.

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31

MU'ALLEM, ABUBAKER SALEM. "PHYSIOLOGICAL CHARACTERISTICS IN COTTON GENOTYPES AS AFFECTED BY PLANT AGE AND PLANTING DENSITIES". Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184031.

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Abstract (sommario):

Physiological characteristics of three cotton genotypes were evaluated for their responses to plant aging under high and low planting density (HPD and LPD) treatments. In addition, the relationship of these physiological characteristics to fruit production were determined. Two genotypes are sympodia producing, "Pima S-6" (Gossypium barbadense L.) and "Deltapine 90" (DPL-90) (G. hirustum L.). The third, a "Cluster Selection" (G. barbadense L.) does not produce sympodia. These genotypes were grown on a Gila sandy loam soil at Tucson, Arizona in 1984 and 1985. Plant physiological characteristics were measured under field conditions at 5 intervals. Leaf physiological characteristics were determined at 7 different leaf ages. LPD treatment significantly reduced total dry weight (TDW), fruit dry weight (FDW), and leaf area index (LAI) in each genotype, but reductions were more pronounced in Pima S-6 and Cluster Selection in both seasons. However, LPD treatment significantly increased plant leaf area, but had no effect on specific leaf weight (SLW), petiole nitrate-nitrogen (Petiole NO₃-N) concentration, leaf area ratio (LAR), and fruiting index (FI), for all genotypes in both seasons. The aging patterns of all physiological characteristics were similar in both planting density treatments, regardless of genotype or season. Regression analyses showed that photosynthetic rate was curvilinearly correlated with leaf age (r² = 0.65 to 0.77, P < 0.01). However, petiole NO₃-N concentration decreased linearly with increasing leaf age (r² = 0.90 to 0.91, P < 0.01). Photosynthetic rate increased curvilinearly with increasing petiole NO₃-N concentration (r² = 0.61 to 0.79, P < 0.01). SLW was not correlated with leaf age, or other leaf physiological characteristics regardless of planting density treatment in 1985. TDW, FI, and LAI were directly related, while petiole NO₃-N concentration and LAR were inversely related to fruit production for all genotypes in both seasons. Multiple regression analyses showed that excluding planting density treatment effect, TDW, FI, and LAI were the most important variables incorporated for fruit prediction in both seasons.

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32

Curtin, Amanda Jane Spotila James R. "Bone growth strategies and skeletochronological age estimates of desert tortoise (Gopherus agassizii) populations /". Philadelphia, Pa. : Drexel University, 2006. http://dspace.library.drexel.edu/handle/1860%20/838.

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33

Adams, Jessica L. "Age and Growth of Three Coastal Pelagic Tuna Species in the Florida Straits". NSUWorks, 2013. http://nsuworks.nova.edu/occ_stuetd/184.

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Abstract (sommario):

Understanding the life history of a species is essential for fully understanding its role within an ecosystem. However, many of the fish species of high ecological value have not been studied due to their less prominent roles in local recreational and commercial fisheries in comparison to other targeted species. This study describes the age and growth patterns of three small tuna species inhabiting South Florida waters: blackfin tuna Thunnus atlanticus, little tunny Euthynnus alletteratus, and skipjack tuna Katsuwonus pelamis. Tuna specimens were collected via donations obtained from various fishing tournaments and charter captains in the areas of the Florida Straits as well as hook-and-line by the Nova Southeastern University Oceanographic Center. Age was described via sagittal otolith deposition patterns. They were removed, dried, sectioned, and rings were counted as well as measured. Validation of the timing of ring deposits was done by marginal increment analysis. Growth parameters were determined by comparison of fish fork length to count measurements. This comparison via the Von Bertalanffy growth equation produced a growth rate for each species: blackfin, L∞ = 95.34 cm, K = 0.28, and t0 = -1.53; little tunny, L∞ = 77.93 cm, K = 0.69, and t0 = -0.69; and skipjack, L∞ = 112.76 cm, K = 0.24, and t0 = -1.70. The curves indicate an average size of an individual of a given species at a certain age. They also give an estimation of a maximum length (L∞) of each species, in addition to specific growth rate, which is indicated by the slope. Parameters of each resulting Von Bertalanffy equation were compared among species. Results were also compared with growth rates currently used in stock assessments by fisheries management organizations, such as the International Commission for the Conservation of Atlantic Tunas (ICCAT).

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34

McInerny, Stephanie A. "Age and growth of red snapper, Lutjanus campechanus, from the southeastern United States /". Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-2/mcinernys/stephaniemcinerny.pdf.

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35

Boom, Suzanna A. M. van den. "Feeding practices and growth of children under 20 months of age in Madrid". Thesis, University of Surrey, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241399.

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36

Alsayegh, Lujain J. "The ecology, age and growth of two muricacean gastropods from shores of Kuwait". Thesis, Bangor University, 2015. https://research.bangor.ac.uk/portal/en/theses/the-ecology-age-and-growth-of-two-muricacean-gastropods-from-shores-of-kuwait(c126f330-2b28-4cc6-ad78-242e685322ab).html.

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Abstract (sommario):

Two predatory muricid gastropods, Thalessa savignyi and Ergalatax junionae commonly occur on the rocky intertidal shores of Kuwait. Three shores, Ra’s Ajūzah, Ra’s Eqaila and Ra’s al Qulay’ah between the north and south of Kuwait covering a distance of ~90Km, were studied to determine the geographical and seasonal abundance of these two muricids. Thalessa savignyi was absent from Ra’s Ajūzah in the north, but increased in abundance towards the south of Kuwait. By contrast the smaller gastropod E. junionae was present on the three shores but decreased in abundance towards the southernmost site, Ra’s al Qulay’ah. Thalessa savignyi prefers rocky platforms and associated fissures which are present on the southern shore whilst small boulders and crevices on the shores in the north of Kuwait were favoured by E. junionae. Egg laying by both species occurred in the laboratory in late June and these egg masses hatched ~30days later in late July. Intertidal recruitment of juveniles (<10mm) appeared into the populations at Ra´s Ajūzah and Ra´s Eqaila between October and January whilst no recruitment was observed at Ra´s al Qulay´ah. Polymodal size frequency distributions in some of the populations were separated into their component size (age) classes using the method of Bhattacharya. Using these estimates of the modal size and ages, Von Bertalanffy growth (VBG) curves were constructed to compare the growth of both species. Thalessa savignyi grew faster than E. junionae and both grew faster at Ra´s al Qulay´ah compared with the other two sites. Growth rings on the operculum and in the statoliths were used to estimate the age of T. savingnyi and E. junionae. Age estimates using whole and polished sections of the operculae were problematic because rings could not be seen through the thick and opaque operculum of T. savignyi. The operculum of E. junionae was thin and transparent but the number of rings counted was almost double those found in the statoliths. Operculae sections did not reveal clear growth rings. A latitudinal variation in the definition and the number of weak growth rings in the statoliths was observed. Generally rings in statoliths of both muricids from the northern sites in Kuwait were clearly defined and they contained less weak rings than statoliths from muricids from the southern site. These statoliths contained a wide variety of strongly and weakly defined rings. It was established from seasonal collections that statolith growth rings are deposited annually between November and January. A larval ring, deposited during the period of life in the egg and a settlement ring, formed at the time of metamorphosis from the plankton, were validated in developing T. savignyi larvae in egg masses and from newly hatched larvae. The age of both species was determined successfully using statoliths and VBG population growth curves constructed. Thalessa savignyi was found to be a faster growing species with a shorter longevity (4 years) than the smaller, longer-lived (5 years) and slower growing E. junionae. In the laboratory both muricids were found to be predators of the tube worm Septibranchia krausii and the mussel Brachidontes variabilis. A comprehensive seasonal survey of the three intertidal shores documented the tidal distributions of the macrofauna and macroalgae. No correlation between the presence of potential prey species and the distribution of T. savignyi and E. junionae was found.

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37

Gaichas, Sarah K. "Age and Growth of Spanish Mackerel, Scomberomorus maculatus, in the Chesapeake Bay Region". W&M ScholarWorks, 1997. https://scholarworks.wm.edu/etd/1539617728.

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38

Goldman, Kenneth J. "Aspects of age, growth, demographics and thermal biology of two lamniform shark species". W&M ScholarWorks, 2002. https://scholarworks.wm.edu/etd/1539616670.

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Abstract (sommario):

Age and growth rates for salmon sharks (Lamna ditropis) in the eastern North Pacific (ENP) were estimated from seasonally formed bands in the vertebrae, and compared to previously published life history parameters for this species from the western North Pacific (WNP). Results of this study show that salmon sharks in the ENP achieve their maximum length at a faster rate, reach sexual maturity at an earlier age and achieve a greater weight-at-length than those in the WNP. Additionally, this dissertation shows that adult salmon sharks maintain a specific body temperature independent of changes in ambient temperature through a combination of physical and physiological means, and essentially function as homeotherms. Due to uncertainty in previous life history parameter estimates for sand tiger sharks (Carcharias taurus) in the western North Atlantic, age and growth rates were re-estimated using a larger sample size and captive individuals injected with oxytetracycline (OTC), a fluorescent skeletal marker. The results support a hypothesis that this species forms one pair of growth bands annually in the vertebral centra, whereas previous growth rate estimates were based on the formation of two bands per year. as such, the growth rate of this species is considerably slower than previously predicted and the population more susceptible to fishing mortality. Demographic analyses were conducted for salmon sharks in the ENP and WNP, and for sand tiger sharks (based on new life history parameter estimates) with uncertainty in vital rates incorporated via Monte Carlo simulations. Density-dependent compensation was included in models where fishing mortality was imposed by increasing sub-adult survivorship from output values generated by a previously published "Intrinsic Rebound Potential" model. The results indicate that both species are extremely vulnerable to fishing mortality and that no fishery should be implemented for sand tiger sharks or salmon sharks in the WNP. Salmon sharks in the ENP were the only population examined that indicated the potential to tolerate any fishing mortality. A comparison of growth completion rates and other life history parameters of ectothermic and endothermic sharks did not indicate that endothermic sharks achieve their maximum length at a faster rate than ectothermic sharks.

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39

Timpe, Douglas. "Age & Growth of the Paddlefish, Polyodon Spathula (Walbaum), in Lake Cumberland, Kentucky". TopSCHOLAR®, 1985. https://digitalcommons.wku.edu/theses/2926.

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Abstract (sommario):

Age and growth parameters of paddlefish from Lake Cumberland were investigated from September 1983 through July 1984. Sex ratios observed were 60 percent male and 40 percent female. The average total length for all paddlefish was 135.3 cm with fish captured in net tackle having a smaller body size than those caught on snag lines. Fish from the Cumberland River exhibited a greater mean body length than those from other parts of the lake, and females were longer than males. The average body weight was 11.8 kg and showed similar trends as body length. Net-captured paddlefish weighed less than those caught with snag lines; fish from the Cumberland River and Lake Cumberland were heavier than those from the South Fork, and females were heavier than males. Growth in length was greatest in the third year of life. The greatest growth in weight of males occurred between the second and third years and decreased thereafter with the exception of the ninth year. Growth of females was highest in the fifth year and remained high until the ninth and tenth years. Females attained the greatest body size in winter and spring; males showed their greatest average size in the spring and summer. A total of 12 age groups was observed in the paddlefish population in Lake Cumberland with Age Groups V and VI dominating the age structure. The longevity of male paddlefish was less than that of females. Different body growth responses were observed for males and females. Males had length-weight "n" exponent values of 2.08 and 2.65 for total length and eye-fork length, respectively which was lower than that of females. Length-weight "n" values for total paddlefish in Lake Cumberland were 3.12 for total length and 3.01 for eye-fork length. Coefficient of Condition values verified the faster, earlier growth of males and faster, later growth by females. Rostrum length averaged 27 percent of the total body length. Growth in rostrum length was closely related to growth in body length. The average survival estimate for paddlefish from Lake Cumberland was 68 percent, with recruitment of significant numbers into the yearly harvest starting at Age VI.

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40

FitzGerald, Charles Michael. "Tooth crown formation and the variation of enamel microstructural growth markers in modern humans". Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360038.

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41

Crawford, Allison Nicole. "Educational Handouts for Parents of Premature Infants/Toddlers Discussing Age Adjusted Growth and Development". Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/319983.

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Abstract (sommario):

Purpose/Objective: The purpose of this practice inquiry was to propose the development and evaluation of Information for Parents of Premature Infants (IPPI). The IPPI is an educational handout that increases parent knowledge by discussing the growth and developmental expectations of a premature infant at a particular adjusted age. The IPPI includes: growth patterns; motor development; nutritional requirements; provider contact information; and useful informational resources. Specifically, this tool encourages the PCP to appropriately assess the premature infant's development based on adjusted age, preventing misdiagnosis or needless referrals. The development of the IPPI was guided by the four principles of Levine's model of conservation, and a plan for implementation and evaluation of the IPPI has been drafted utilizing the five components of the RE-AIM framework. Introduction: Each year one-in-nine babies are born prematurely in the United States. Over the last 25 years the rate of premature birth has increased by 36%. Compared to parenting a term infant, parents of premature infants face a significant number of challenges and stress. The cause of such stress is due to a lack of knowledge regarding the unique physical and developmental care needs of a premature infant and the lack of available educational resources that are designed to address this deficit. Rationale: The increased incidence of premature births has placed an enormous burden on primary care providers (PCP) to meet the exceptional health and developmental needs of this vulnerable population. The neurodevelopmental expectations for premature infants vary significantly when compared to those of full-term infants and in addition to the risk for neurodevelopment disabilities there is a significant amount of stress faced by parents. In order to manage the care and physical needs of a preterm infant and have the confidence to bond with their fragile infants, parents need a great deal of support and education regarding the unique physical and developmental needs of their premature infant. Furthermore, parents must rely on the baby's PCP to have the ability to recognize the sequelae that is associated with premature birth and provide appropriate education, anticipatory guidance, resources, and reassurance.

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42

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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43

Feichtinger, Erin Elizabeth. "Beyond Age and Stage: Consequences of Individual Variation in Demographic Traits". Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6836.

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Abstract (sommario):

Within natural populations, individuals vary in their propensity to grow, survive and produce offspring. Additionally, fates of individuals are often correlated and non-independent as a result of shared genes, rearing environment or both. Variation in demographic traits can change population dynamics over time. The effects of variation in individual growth rate on population growth rate, net reproductive rate and generation time are examined, along with quantifying the sources of variation in survival of a long-lived cooperatively breeding bird, the Florida Scrub-Jay (Aphelocoma coerulescens). I built a 2 stage population model with two growth phenotypes, fast and slow, and simulated all parameter values using R 3.3.1. Variation in individual maturation rate changes population dynamics, especially in the presence of phenotypic correlation between parents and offspring in growth phenotype. I used Cox Proportional Hazard models with a covariance structure derived from a kinship matrix using the R packages survival and kinship2. Survival of juvenile Florida Scrub-Jays is strongly dependent on kinship, or the degree of relatedness between individuals, in addition to body mass, social structure of the natal territory, natal territory quality and environmental conditions of the rearing period. Breeder Florida Scrub-Jay survival is mainly structured by group size, kinship, yearly variation in environmental conditions and territory quality.

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44

Gordon, A. K. (Andrew K. ). "The effect of diet and age-at-weaning on growth and survival of clownfish Amphiprion percula (Pisces : Pomacentridae)". Thesis, Rhodes University, 1999. http://hdl.handle.net/10962/d1005114.

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Abstract (sommario):

The aim of this study was to improve the rearing of common clownfish Amphiprion percula, by weaning juveniles from a live feed to a formulated feed as early as possible, while still maintaining good growth and survival. The growth response of A. percula to a formulated dry feed was initially investigated. There was no difference in growth rate of juveniles fed a formulated feed, and the formulated feed supplemented with either Artemia or a Donax serra / Penaeus indicus combination. Amphiprion percula readily consumed the formulated feed, and the fishmeal/casein combination appeared an acceptable protein source. As the amount of protein included in a diet can have a profound effect on growth, the optimal dietary protein level for juvenile A. percula was investigated by feeding semipurified diets containing graded levels of protein, ranging from 40-65%. There was no difference in the growth rates of juveniles fed the various diets, however all diets promoted good growth with an average weight gain of 419%, and thus for the purposes of this study the diet formulation was deemed adequate. The histological study of the digestive system of larval A. percula revealed that the alimentary canal was advanced at hatching and that larvae start exogenous feeding immediately. Three days after hatch (DAH) the yolk sac is completely absorbed. In the hind-gut epithelium of 5-day-old larvae small supranuclear inclusion vacuoles appear, suggesting pinocytotic digestion, and by 7 DAH gastric glands are established in the epithelium of the stomach. Nine DAH supranuclear inclusion vacuoles appear in the epithelium of the mid-gut, indicating extracellular digestion and absorption across the lumen. As pinocytotic digestion of protein is less efficient than extracellular digestion, especially in the case of formulated feeds, it was hypothesised that the digestive system of A. percula could only effectively digest formulated feeds 9 DAH onwards. The two weaning experiments designed to test this hypothesis revealed that A. percula was able to utilise the formulated feed, without reduction in survival, from 7 DAH onwards. However, in terms of growth, the optimal time to wean juveniles from the live feed to the formulated dry feed was between 15 to 20 DAH. As A. percula accept a formulated feed and can benefit nutritionally from it, the dependence of larvae and juveniles on live feed can be reduced. This study has shown that the rearing of A. percula can been simplified and improved by weaning from 7 DAH with no reduction in survival, and from 15 to 20 DAH with no reduction in growth.

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45

Meyers, Robert William. "The influence of age, growth and maturation upon maximal sprint speed in male youth". Thesis, Cardiff Metropolitan University, 2016. http://hdl.handle.net/10369/7974.

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Abstract (sommario):

The literature pertaining to the development of maximal sprint performance in male youth is sparse. Existing literature suffers from a combination of small sample sizes, a lack of control for the influence of maturity, methodological approaches where maximal speed is not measured or failure to explore the spatiotemporal, kinematic or kinetic characteristics associated with sprint performance in male youth. On this basis, the aim of this thesis was to investigate the influence of growth and maturation upon maximal overground sprint performance in a large cohort of 11-16 year old boys. Sprint and spatiotemporal variables were found to have acceptable reliability (CV = 3.8-12.6%). Cross-sectional analysis of a large sample of boys showed a maturational effect on sprint performance, with the period of peak height velocity (PHV) eliciting the greatest enhancements in maximal sprint speed. Furthermore, whilst improvements in step length (SL) were observed with increasing maturity, step frequency (SF) was largely stable, with some evidence of small declines during the pre-PHV period. Further cross-sectional analysis revealed that pre-PHV boys were SF-reliant during maximal sprint performance, whilst post-PHV boys were deemed SL-reliant. Analysis of body size revealed that stature had a positive influence upon maximal sprint performance, whilst mass had a negative influence. Cross-sectional analysis of the kinetic characteristics of maximal sprint performance revealed that both relative maximal force and relative vertical stiffness did not increase with advancing age and maturity, but these variables were deemed to be the most important predictors of maximal sprint performance in male youth, independent of age and maturity. Furthermore, longitudinal analysis confirmed that relative force production and relative vertical 4 stiffness were the most important predictors of maximal sprint performance in boys, and that those who had passed the period of PHV experienced greater gains in maximal speed than those who remained pre-PHV. Collectively the results of the empirical studies highlight that maximal sprint speed in male youth develops with advancing age and maturation, due to an interaction of changes in SL and SF. These changes are partly related to changes in body size and the period of PHV appears to be a key period during the development of maximal speed. However, there are also key predictors of speed, such as relative force and relative vertical stiffness that do not change between the ages of 11 and 16 years old.

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46

Bertschy, Kirk A. "The influence of age-specific survivorship and growth on pumpkinseed, Lepomis gibbosus, life histories". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq21682.pdf.

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47

Ingram, Travis R. "Age, growth, and fecundity of Alabama shad (Alosa alabamae) in the Apalachicola River, Florida". Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1181251015/.

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48

LI, MING-LIN, e 李明玲. "Age and growth of juvenile Pomacentrus coelestis (Pisces: Pomacentridae)". Thesis, 1991. http://ndltd.ncl.edu.tw/handle/90175467939478573785.

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49

How, Karl T. S. "Modelling sugarcane growth in response to age, insolation and temperature". Thesis, 1986. http://hdl.handle.net/10125/9974.

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50

"Change of relative size of renal cortex and medulla related to age". 1997. http://library.cuhk.edu.hk/record=b5889290.

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Abstract (sommario):

Fung Kwai Ching.
Thesis (M.Phil.)--Chinese University of Hong Kong, 1997.
Includes bibliographical references (leaves i-ix (last gp.)).
Acknowledgement --- p.i
Legend for graphs --- p.ii-iii
Legend for pictures --- p.iv
Legend for diagrams --- p.v
Legend for tables --- p.vi
Abstract --- p.vii-viii
Introduction --- p.1-17
Chapter 1 --- Known Anatomy and Physiology --- p.1-2
Chapter 2 --- The Nephron --- p.3-4
Chapter 3 --- Renal Vasculature --- p.5-7
Chapter 4 --- Summary of renal anatomy from infancy to children from review of literature --- p.8
Chapter 5 --- Function of the kidney --- p.9-17
Imaging Background --- p.18-23
Chapter 1 --- Neonates and infants kidneys- sonographic appearance of echogenicity --- p.18-19
Chapter 2 --- Prominence of medullary pyramicd (MP) --- p.20-21
Chapter 3 --- Morphometric Studies --- p.22-23
Aim of Study --- p.24
Method --- p.24-41
Chapter 1 --- Method --- p.24-30
Chapter 2 --- """Limitations"" to the technique" --- p.30-34
Chapter 3 --- Establishing the technique --- p.35-41
Results --- p.42-62
Chapter 1 --- Comparison of kidney length with age --- p.42-44
Chapter 2 --- Corticomedullary and age relationship --- p.45-48
Chapter 3 --- Medullary thickness correlated with age --- p.48-52
Chapter 4 --- Sum of the cortical thickness and medullary thickness versus kidney length --- p.53-54
Chapter 5 --- Compare CMR with kidney length and --- p.55-56
Chapter 6 --- CMR versus age --- p.57-59
Chapter 7 --- Mean of CMR related to age group --- p.57-59
Chapter 8 --- Compare CMR with kidney length and age --- p.60
Chapter 9 --- Compare gender and CMR --- p.60-61
Chapter 10 --- Compare laterality and CMR --- p.60
Result summary --- p.62
Discussion --- p.63-84
Chapter 1 --- Cortex --- p.63-65
Chapter 1.1 --- Cortex: anatomy --- p.66-67
Chapter 1.2 --- Cortex: physiology --- p.67-76
Chapter 2 --- Medulla --- p.76-81
Chapter 2.1 --- Medulla: anatomy --- p.76
Chapter 2.2 --- Medulla: physiology --- p.76-81
Chapter 3 --- "Corticomedullary ratio, CMR" --- p.82-83
Chapter 4 --- CMR and Kidney Length --- p.83
Chapter 5 --- "The CMR, Kidney Length and Age" --- p.83
Chapter 6 --- Corticomedullary Ratio and its relationship to actual corticomedullary volume ratio --- p.84
Chapter 7 --- "Laterality, Sex of the subjects" --- p.84
Implications --- p.84-94
Clinical pathological cases and corticomedullary ratio CMR --- p.90-94
Conclusion --- p.94-95
Appendix --- p.96-103
Chapter 1 --- Morphologic Development and Anatomy of the Kidneys and Urinary Tract --- p.96-98
Chapter 2 --- Renal Perfusion and Glomerular Filtration --- p.99-101
Chapter 3 --- Classification of renal diseases --- p.102-103
References

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