Height Growth Curves Research Articles

Climatic factors defining the height growth curve of forest species

The aim of this study was to modify several existing biological models by including several predictive variables that take into account the effect of climatic factors on tree height growth. Tree height was measured from 2007 to 2014 on 18 trees for each of the following species: Eucalyptus urophylla × Eucalyptus grandis, Parapiptadenia rigida, Peltophorum dubium, Mimosa scabrella and Schizolobium parahybae. Different existing nonlinear models were fitted to the observed data, and the best fitting models were selected. The inclusion of climatic variables into the selected models (mainly minimum temperature and rainfall) improved their predictions of tree height growth with age, and provided more accurate estimates than those obtained by traditional nonlinear models. Simulations were carried out to explore the variation of tree height growth under different minimum temperature and precipitation regimes. The effects of frost and rainfall variation on height growth curves and their consequences for forest management are discussed.

The use of a wave boundary layer model in SWAN

AbstractA wave boundary layer model (WBLM) is implemented in the third‐generation ocean wave model SWAN to improve the wind‐input source function under idealized, fetch‐limited condition. Accordingly, the white capping dissipation parameters are recalibrated to fit the new wind‐input source function to parametric growth curves. The performance of the new pair of wind‐input and dissipation source functions is validated by numerical simulations of fetch‐limited evolution of wind‐driven waves. As a result, fetch‐limited growth curves of significant wave height and peak frequency show close agreement with benchmark studies at all wind speeds (5–60 m s−1) and fetches (1–3000 km). The WBLM wind‐input source function explicitly calculates the drag coefficient based on the momentum and kinetic energy conservation. The modeled drag coefficient using WBLM wind‐input source function is in rather good agreement with field measurements. Thus, the new pair of wind‐input and dissipation source functions not only improve the wave simulation but also have the potential of improving air‐sea coupling systems by providing reliable momentum flux estimation at the air‐sea interface.

Growth Curves for Diameter and Height Using Mixed Models: An Application in Eucalyptus Seedling

The growth of a tree or a forest settlement is of great value to a forest enterprise, because many decisions are directly dependent of this information, for instance, determining the optimal cutting age. This study aims to apply a new class of models to fit growth curves for diameter and height of Eucalyptus grandis X Eucalyptus urophylla seedling data. Data were collected from a trial conducted in a green house at the Natural Resources Department at School of Agriculture, Botucatu, S?o Paulo, Brazil. The experiment’s design was completely randomized with eight treatments and four replications. In this trial, the growth variables referring to the height and the diameter were evaluated, being measured five and four times, respectively. The methodology was carried in a mixed longitudinal model using a new approach based on Box-Cox Normal (BCN) distribution, and comparisons with this model were made assuming normality of the data. The results revealed that the BCN mixed model provided similar results to the standard model in order to estimate growth curves; however, the BCN model was the best result according to Akaike criterion, considering the slight asymmetry in the data set. This approach is of great interest in case of outliers and robust procedures for parameter estimation.

Modeling the Growth of Thoroughbred Horses: The Relationship of Birth Height, Gestation Time, and Wither Height at Maturity

This article presents an analysis examining the wither height growth curves of 33 Thoroughbred horses from birth to maturity. The growth curve of each animal was analyzed, and the mature height was determined. Having established each animal‘s mature height, the growth curves were then normalized using the individual mature height and gestation length. A birth ratio (B rh ) was established using the length of gestation divided by the fraction of maturity at birth (F bh ), and this value was found to be nearly identical for all horses in the study, indicating that the growth of each horse was very similar in normalized time. A relationship was developed predicting F bh as a function of birth height, gestation time, and the animal‘s sex, and a procedure is presented to estimate an animal‘s mature height based on F bh from the developed expression. The estimates of mature size were reasonable in most instances, and comparisons are shown indicating the efficacy of the predicted values compared to the values of mature wither height found from the growth curve regressions.

Nonparametric adaptive Bayesian regression using priors with tractable normalizing constants and under qualitative assumptions

Shape constrained regression models are useful for analyzing data with specific shape responses, such as (monotone) dose-response curves, the (concave) utility functions of a risk averse decision maker, the (increasing) growth curves of children's height through time, that are particularly common in medicine, economic and epidemiological studies. This paper proposes a new adaptive Bayesian approach towards constructing prior distributions, with known normalizing constants, which enables us to take into account combinations of shape constraints and to localize each shape constraint on a given interval. Our strategy enables us to compute the simulation from the posterior distribution using a reversible jump Metropolis–Hastings scheme. The major advantages of the proposal are its flexibility achieved by adjusting local shape restrictions to detect better the high and low variability regions of the data and to facilitate the control of the regression function shape when there is no data at all in some regions. We give asymptotic results that show that our Bayesian method provides consistent function estimator from the adaptive prior. The performance of our method is investigated through a simulation study with small samples. An analysis of two real data sets is presented to illustrate the new approach.

Estimating Site Index From Short-Term TanDEM-X Canopy Height Models

The tree height growth from three vegetation seasons was fitted to height growth curves in order to estimate the site index, which is a variable related to forest site productivity. The tree height growth was evaluated for four different cases, in which remote sensing data from TanDEM-X and airborne laser scanning were used. The used method requires a digital terrain model and knowledge about the tree species. Furthermore, the remote sensing data were calibrated using Lorey's mean height heights or airborne laser scanning data. It was found that four annual acquisitions of calibrated TanDEM-X data covering three vegetation seasons could be used for estimating the site index on 27 0.5-ha field plots with 4.4-m (12.1%) RMSE. The site index could in a similar manner be estimated from only two airborne laser scanning acquisitions, before and after four vegetation seasons, with 2.3-m (6.3%) RMSE.

Physical growth curves of indigenous Xavante children in Central Brazil: results from a longitudinal study (2009–2012)

Background: The nutritional profile of Indigenous children in Brazil is comparable to those observed in some of the least developed regions of the world.Aim: Weight and height growth curves were characterised based on longitudinal data from a local Indigenous population experiencing the double burden of child under-nutrition and adult obesity.Subjects and methods: Anthropometric data were collected in six waves from 2009–2011 for children <10 in two proximate Xavante villages in Central Brazil. Prevalence rates for stunting, wasting and thinness were calculated using WHO references. Weight and height data were adjusted for generalised additive mixed models to generate growth curves.Results: Prevalence rates of stunting and wasting were high, but cases of thinness and excess weight were negligible. Weight and height began close to WHO medians, but fell substantially before 12 months. Boys but not girls were able to catch-up in weight before age 10. From 3–10 years, height for both sexes remained between −2 and 0 z-scores.Conclusion: Impaired Xavante growth before 1 year followed by inconsistent recovery before 10 years reflects health and wellbeing disparities with regard to the Brazilian national population and a complex epidemiology of growth involving rapid nutritional change.

Temporal variability of aging error and its potential effects on black spruce site productivity estimations

As a black spruce (Picea mariana (Mill.) BSP) tree expands its adventitious rooting system, its root collar is amalgamated into the stump. Total tree age determined by ring counts at ground level or 1m height on the stem is thus underestimated. This age underestimation would increase with stand age because of the continuous growth of adventitious roots and the sinking of the stem under its own weight. Tree age underestimation could lead to productivity overestimation. The goal of this study was to evaluate the effect of stand age on aging error of trees and productivity estimation. Three trees within each of fifteen non-paludified and naturally regenerated black spruce stands aged 37–204years were excavated to harvest the stump and locate the root collar. Stump sections were cross-dated down to the root collar to obtain trees’ total biological age which was then compared to a ring count done at 1m height. Height and volume growth curves obtained by stem analysis were compared with those derived from Pothier and Savard’s (1998) models. Age difference between total biological age and age at 1m (aging error) ranged 9–58years and significantly increased with stand age. Site indices (SI; height of trees at 50years of age) were significantly over-estimated by using age at 1m, and the overestimation significantly increased with stand age and aging error. The use of age at 1m lead to poor modeling of height- and volume-growth trajectories, as early height and volume-growth obtained through stem analysis was slower than predicted and stand senescence also occurred later. Due to their period of horizontal growth, seedlings don’t accumulate any height during the first years. Additionally, early tree growth of our oldest trees seems to have been slower than early growth of our younger trees, probably because of less favorable growing conditions. Despite large differences between volume and height growth trajectories, predicted volumes from theoretical SI calculations were not significantly different from observed values using stem analysis, at the time of sampling. Predictive models should nevertheless be adjusted by using total biological age or time since the last fire, to consider the first years of slow growth and to obtain more accurate productivity estimations.

Colombian reference growth curves for height, weight, body mass index and head circumference.

Published Growth studies from Latin America are limited to growth references from Argentina and Venezuela. The aim of this study was to construct reference growth curves for height, weight, body mass index (BMI) and head circumference of Colombian children in a format that is useful for following the growth of the individual child and as a tool for public health. Prospective measurements from 27 209 Colombian children from middle and upper socio-economic level families were processed using the generalised additive models for location, scale and shape (GAMLSS). Descriptive statistics for length and height, weight, BMI and head circumference for age are given as raw and smoothed values. Final height was 172.3 cm for boys and 159.4 cm for girls. Weight at 18 years of age was 64.0 kg for boys and 54 kg for girls. Growth curves are presented in a ± 3 SD format using logarithmic axes. The constructed reference growth curves are a start for following secular trends in Colombia and are also in the presented layout an optimal clinical tool for health care.

Longitudinal study of growth of children with unilateral cleft lip and palate: 2 to 10 years of age.

Objective : To study the growth of children with complete unilateral cleft lip and palate (UCLP) from 2 to 10 years of age and to assess whether growth varied from that of children without UCLP (typical children). Design : Physical growth was one of the outcome measures of a National Institutes of Health-sponsored longitudinal, prospective clinical trial conducted by the University of Florida and the University of São Paulo. Setting : Hospital of Rehabilitation of Craniofacial Anomalies, University of São Paulo (HRAC-USP), Bauru, Brazil. Main Outcome Measures : Height and weight were prospectively measured for 360 healthy children with UCLP who were nonsyndromic, belonged to median socioeconomic status, and received health care at HRAC-USP. To compare growth of children with UCLP to that of typical children, growth curves for UCLP were developed and compared with World Health Organization curves for 2006 and 2007, which were used as reference for typical children. Third-degree polynomials were used to explain the relationship of length and weight with age. Confidence limits of 95% were used for the mean curve using the statistic Z ~ N (0,1). Results : Children with UCLP from 2 to 10 years old presented height and weight growth curves similar to those of typical children for both genders. Conclusion : Children with UCLP from 2 to 10 years old presented physical growth similar to that of typical children.

Body Mass Index and Height Growth Curves are influenced by Sexual Maturation Status in Brazil: Cross-Sectional Study

Abstract Background: To describe and analyze growth curves of body mass index (BMI) and height according to sexual maturation status in children and adolescents aged 8-14 years old in the city of Florianopolis, Santa Catarina, Brazil. Methods: Cross-sectional study conducted in 2007 with a random sample of 2,339 students from public and private elementary school. Excess weight was determined by BMI curves of the World Health Organization according to sex and age. Sexual maturation was self-assessed and classified according to Tanner stages of sexual development. Tertiles of age in each sexual maturation stage were used to classify individuals in early, normal or late sexual maturation. Growth curves of BMI and height were estimated using median values for each sex, using six degree polynomial to smooth the curve. Results : We observed different growth curves of BMI and height according to sexual maturation status for both boys and girls. Early sexual maturation is associated with increased BMI z score to boys until 11 years of age and to girls in all groups age, and with increased height z score to boys in all age groups and in girls of 9 -12.5 years of age. Late sexual maturation is associated with lower values of BMI Z score in boys between 10 to 12 years of age and slower evolution of BMI Z score in girls. Conclusion : The sexual maturation seems to affect directly the evolution of BMI and height and should be considered in the assessment of nutritional status during childhood.

Growth charts for non-growth hormone treated Prader-Willi syndrome.

The goal of this study was to generate and report standardized growth curves for weight, height, head circumference, and BMI for non-growth hormone-treated white male and female US subjects with Prader-Willi syndrome (PWS) between 3 and 18 years of age and develop standardized growth charts. Anthropometric measures (N = 133) were obtained according to standard methods from 120 non-growth hormone-treated white subjects (63 males and 57 females) with PWS between 3 and 18 years of age. Standardized growth curves were developed for the third, 10th, 25th, 50th, 75th, 90th, and 97th percentiles by using the LMS method for weight, height, head circumference, and BMI for PWS subjects along with the normative third, 50th, and 97th percentiles from national and international growth data. The LMS smoothing procedure summarized the distribution of the anthropometric variables at each age using three parameters: power of the Box-Cox transformation λ (L), median μ (M) and coefficient of variation δ (S). Weight, height, head circumference, and BMI standardized growth charts representing 7 percentile ranges were developed from 120 non-growth hormone-treated white male and female US subjects with PWS (age range: 3-18 years) and normative third, 50th, and 97th percentiles from national and international data. We encourage the use of syndrome-specific growth standards to examine and evaluate subjects with PWS when monitoring growth patterns and determining nutritional and obesity status. These variables can be influenced by culture, individual medical care, diet intervention, and physical activity plans.

Fundal height growth curve patterns of pregnant women with term low birth weight infants.

PurposeTo investigate the patterns of fundal height (FH) growth curve in pregnant women with term low birth weight (LBW) infants compared with the standard FH growth curve for Thai women.Subjects and methodsA retrospective study was conducted at the four governmental general hospitals in the northern part of Thailand between 2009 and 2011. All data were obtained from antenatal records and labor registry. Serial FH measurements in centimeters of 75 pregnant women with term LBW infants were plotted against the standard FH growth curve for Thai women throughout pregnancy.ResultsSix patterns of the FH growth curve were summarized: pattern I: FH below or around the tenth percentile throughout pregnancy (n=17, 22.7%); pattern II: FH below normal in early pregnancy, caught up with normal, then decelerated or stagnant (n=19, 25.3%); pattern III: FH normal in early pregnancy, then decelerated or stagnant (n=17, 22.7%); pattern IV: FH normal in early pregnancy, decelerated or stagnant, then caught up to normal (n=6, 8.0%); pattern V: FH normal throughout pregnancy except for the last visit (n=6, 8.0%); and pattern VI: FH normal throughout pregnancy (n=10, 13.3%).ConclusionPatterns I–V may be used to recognize women who are likely to deliver term LBW infants from early pregnancy, during pregnancy, and on the day of admission for labor. Ultrasound evaluation is still recommended in cases with known risk factors that might be undetectable by FH, or in cases where FH measurement may be inaccurate.

한국 서해안 갈색띠매물고둥, Neptunea (Barbitonia) arthritica cumingii의 연령과 성장

The age and growth of Neptunea (Barbitonia) arthritica cumingii sampled from the West Sea of Korea were determined from 1,062 operculums from October 2007 to September 2008. Age of Neptunea (Barbitonia) arthritica cumingii was determined from the rings on the operculum. The relationship between shell height (SH; mm) and shell width (SW; mm) was expressed by the following equation : SW = 0.5757 SH + 0.222 (R = 0.8723), and shell height (SH; mm) and total weight (TW; g) was highly correlated by the equation : TW = 0.0002 SH (R = 0.9121). The main spawning periods was estimated June to July through fatness index analysis. The relationship between shell height and ring radius of operculum in each ring group was expressed as a regression line. Therefore, there is a correspondence in each ring formation. Based on the monthly variations in the marginal index (MI) of the operculum, it is assumed that the ring of this species was formed once a year during the period of July to August. Growth curves for shell height (SH) and total weight (TW) fitted to the von Bertalanffy's equation were expressed as follows :        

Construction of national standards of growth curves of height and weight for children using cross-sectional data.

Growth curves are the most important tools for the assessment of growth of children, which could further helps to develop preventive interventions. Geographical and physical differences necessitate using national growth curves. This study aims to construct growth curves using anthropometric measurements namely weight and height for Indian children using cross-sectional data from National Family and Health Surveys. Box-Cox power exponential, a flexible distribution, was used that offers to adjust kurtosis and improves the estimation of extreme percentiles. LMS-methods that fit skewed data adequately and generate fitted curves that follow closely the empirical data, with maximum penalized likelihood, Akaike information criteria (AIC) and generalized AIC with penalty 3 were used to construct the growth curves. Before fittings this model factors which influence the nutritional status of children were examined, similar to World Health Organization (WHO) (2006) factors, namely standard infant feeding practices, sanitation, non-smoking mothers additionally poverty (household consumable assets based). Model fitted in LMS-model and standard based on height and weight for children aged 0-60 months was obtained after iteration for degrees of freedom for the parameters. Growth curves for mean Z-scores and percentiles were constructed for both sexes and significant lower values were noticeably found to set as growth-standard compared to WHO-standards. Study showed the prospect of constructing regional/national growth curve and their need for the assessment of children's growth, which could help to identify undernourished-children at national level. There is an urgent need to collect longitudinal data of children to fit the growth curve of children in India.

Fundal Height Growth Curve for Underweight and Overweight and Obese Pregnant Women in Thai Population

Objectives. To develop fundal height growth curves for underweight and overweight and obese pregnant women based on gestational age from last menstrual period and/or ultrasound. Methods. A retrospective study was conducted at four hospitals in the northern part of Thailand between January 2009 and March 2011. Fundal height, gestational age, height, and prepregnancy weight were extracted from antenatal care and delivery records. Fundal height growth curves were presented as smoothed function of the 10th, 50th, and 90th percentiles between 20 and 40 weeks of gestation, derived from multilevel models. Results. Fundal height growth curve of the underweight was derived from 1,486 measurements (208 women) and the overweight and obese curve was derived from 1,281 measurements (169 women). The 50th percentile line of the underweight was 0.1–0.4 cm below the normal weight at weeks 23–31 and 0.5–0.8 cm at weeks 32–40. The overweight and obese line was 0.1–0.4 cm above the normal weight at weeks 22–29 and 0.6–0.8 cm at weeks 30–40. Conclusions. Fundal height growth curves of the underweight and overweight and obese pregnant women were different from the normal weight. In monitoring or screening for abnormal intrauterine growth in these women, fundal height growth curves specifically developed for such women should be applied.

Provenance variation in height development of Albizia falcataria under three levels of spacing in East Java, Indonesia

Abstract Nine provenances of Albizia falcataria were planted at three square spacing levels (2, 3, and 4 m) in a split-plot design at Jember in East Java, Indonesia and measured annually for six years, which is three quarters of its rotation age. The effect of spacing on mean height development became progressively evident, due to the decline in growth at closer spacing caused by intensified competition, in six provenances, i.e., three provenances each from Java and East Indonesia, which were considered better adapted to the site because of their better growth and higher survival. On the contrary, the height growth curves of two provenances from New Guinea were almost identical, irrespective of spacing, indicating a lack of plasticity to the favorable environment at wider spacing. Dominant height was defined as the average of the five tallest trees per sub-plot (350 stems/ha), the growth curves at the three spacing levels were similar in the above-mentioned six provenances and were regarded as a single curve according to AIC-values. In contrast, dominant height growth curves of the New Guinea provenances were differentiated in the order of 2, 3, and 4 m spacing, approximately proportional to the intensity of choosing dominant trees per sub-plot. These results suggest that provenance variation exists for mean and dominant height and their response to different spacing. The cause of this variation was presumably attributable to the difference in competitive ability as well as the plasticity to the given environment. The use of dominant height for growth modeling of A. falcataria was found to be the most suitable for the adapted provenances.

Fundal Height Growth Curve for Thai Women

Objectives. To develop fundal height (FH) growth curve from normal singleton pregnancy based on last menstrual period (LMP) and/or ultrasound dating for women in the northern part of Thailand. Methods. A retrospective time-series study was conducted at four hospitals in the upper northern part of Thailand between January 2009 and March 2011. FH from 20 to 40 weeks was measured in centimeters. The FH growth curve was presented as smoothed function of the 10th, 50th, and 90th percentiles, which were derived from a regression model fitted by a multilevel model for continuous data. Results. FH growth curve was derived from 7,523 measurements of 1,038 women. Gestational age was calculated from LMP in 648 women and ultrasound in 390 women. The FH increased from 19.1 cm at 20 weeks to 35.4 cm at 40 weeks. The maximum increase of 1.0 cm/wk was observed between 20 and 32 weeks, declining to 0.7 cm/wk between 33 and 36 weeks and 0.3 cm/wk between 37 and 40 weeks. A quadratic regression equation was FH (cm) = −19.7882 + 2.438157 GA (wk) − 0.0262178 GA2 (wk) (R-squared = 0.85). Conclusions. A demographically specific FH growth curve may be an appropriate tool for monitoring and screening abnormal intrauterine growth.

Site index for teak in Colombia

Determination of site quality is a basic tool for proper selection of locations and species, in management of forest plantations. Throughout the Caribbean studies of site quality are few and are hampered by statistical limitations, inappropriate growth models, and limited data. We fitted growth curves for dominant height to evaluate and classify site quality of teak (Tectona grandis) plantations by using data from 44 permanent sample plots established since 1990 in 3–22 years old teak plantations in the Colombian Caribbean region. We used Korf’s and von Bertalanffy’s models to fit curves as non-linear effects models. Both models, with a single random parameter, were considered as adequate for dominant height growth modelling, but Korf’s model was superior. The resulting curves were anamorphic and closely reflected high variability in site quality. Five site classes were clarified: at a base age of 12 years old, teak reached a mean dominant height of 24.8 m on the best sites, 9.8 m in the worst sites, and in the averages sites, 15.8–18.8 m. Using this model, we identified the best and the worst sites for teak plantations in the Caribbean region. This model proved a useful tool, not only for site quality evaluation, but also for improved teak plantation planning and management.

Changes of mandibular ramal height, during growth in unilateral hemifacial microsomia patients and unaffected controls

The aim of this study was to design mandibular ramal height growth curves for patients with HFM and compare those with the curves for a Dutch reference population. Two hundred fifty-one pre-operative orthopantomograms (OPTs) from 84 patients with unilateral HFM were used in conjunction with a control set of 2260 OPTs from 329 healthy individuals from the Nijmegen Growth Study (NGS) to determine mandibular ramal distances. For grades I/IIa and IIb/III, and for both sides, growth curves were constructed for mandibular ramal height with a linear curve-fitting procedure. This procedure revealed a significant difference between HFM patients and the NGS control group (p < 0.001); both in the mild and severe group mandibular ramal height differed significantly between the affected and non-affected side (p < 0.001). Growth was similar between HFM patients and the NGS control group. HFM patients therefore start with a smaller mandible and end with a smaller mandible, but experience growth similar to the Dutch normal population. These growth curves may aid the timing and determination of the combined surgical orthodontic treatment plan for HFM patients.