scholarly journals Comparison of Prediction Equations for Estimating Inside Bark Diameters for Yellow-Poplar, Red Maple, and Red Pine in West Virginia

2009 ◽  
Vol 26 (1) ◽  
pp. 5-8 ◽  
Author(s):  
John R. Brooks ◽  
Lichun Jiang
Keyword(s):  
West Virginia ◽  
Single Species ◽  
Prediction Equation ◽  
Red Pine ◽  
Red Maple ◽  
Nonlinear Prediction ◽  
Prediction Equations ◽  
Yellow Poplar ◽  
Taper Function ◽  
Almost All

Abstract The ability to predict inside bark diameters was investigated using taper data for red maple, red pine and yellow-poplar from several stands in West Virginia. Inside bark estimates were based on Grosenbaugh's STX prediction equations, a segmented polynomial taper function fitted to inside bark diameter data, an existing polynomial prediction equation published for several hardwood species in this region and a nonlinear prediction equation fitted to the taper data. Grosenbaugh's STX is a computer program for processing tree measurements and includes three equations to allow flexibility and greater accuracy in predicting inside bark upper stem diameters. The nonlinear equation had the smallest overall prediction error in almost all cases investigated. The taper function had the largest error but does not require knowledge of the specific upper stem outside bark diameter. No single STX bark option was found to be optimal for all species or for a single species from two different geographic regions.

scholarly journals Influence of Species on Site Selection and Timber Removal: A Case Study for West Virginia

2007 ◽  
Vol 24 (2) ◽  
pp. 146-148 ◽  
Author(s):  
William Luppold ◽  
Delton Alderman
Keyword(s):  
West Virginia ◽  
Sugar Maple ◽  
Considerable Change ◽  
Red Maple ◽  
Yellow Poplar ◽  
Tolerant Species ◽  
Shade Tolerant Species ◽  
Canopy Removal ◽  
Specific Species

Abstract Over the last 40 years the composition of West Virginia forests has been changing as selective cutting practices have removed larger-diameter timber of specific species and partial canopy removal has fostered the regeneration of shade-tolerant species such as red maple. However, since the mid-1990s there has been considerable change in the number of markets accepting lower-quality and smaller-diameter roundwood, especially yellow-poplar. These changes have increased the number of roundwood markets and thus have increased the potential for harvesting based on silvicultural objectives or clearcuts. An examination of harvesting and merchandising practices for 28 harvest sites in West Virginia found an average of four merchandising separations or markets per site. Although the presence of new markets may have increased the section of sites containing yellow-poplar and the removal of this species from these sites, the continuation of diameter-limit cutting seems to have the greatest effect on which trees are removed. This pattern of partial harvests continues to favor the regeneration of shade-tolerant species such as red and sugar maple.

Chromated Copper Arsenate Preservative Treatment of North American Hardwoods. Part 1. CCA Fixation Performance

Holzforschung ◽  
2000 ◽  
Vol 54 (6) ◽  
pp. 577-584 ◽  
Author(s):  
T. Stevanovic Janezic ◽  
P.A. Cooper ◽  
Y.T. Ung
Keyword(s):  
Populus Tremuloides ◽  
North American ◽  
Acer Rubrum ◽  
Chromated Copper Arsenate ◽  
Red Pine ◽  
Red Oak ◽  
Red Maple ◽  
White Birch ◽  
Yellow Poplar ◽  
Copper Arsenate

Summary We have examined chromated copper arsenate (CCA) wood preservative fixation at two selected temperatures in seven common North American hardwood species: red maple (Acer rubrum L.), white birch (Betula papyrifera Marsh.), yellow poplar (Liriodendron tulipifera L.), trembling aspen (Populus tremuloides Michx.), red oak (Quercus rubra L.), basswood (Tilia americana L.) and American beech (Fagus grandifolia Ehrh.). The softwood red pine (Pinus resinosa Ait.) was included for comparison. CCA component fixation was monitored by the expressate method at both 21°C and 50°C under non-drying conditions. Hexavalent chromium (CrVI) and total Cr, Cu and As contents of the expressate were determined at different times during fixation. Based on CCA fixation results it was possible to divide the examined hardwoods into a fast fixing group (beech, red oak and red maple), intermediate group (white birch and red pine) and slow fixing group (aspen, yellow poplar and basswood). The variable fixation rates for the different species could not be directly related to different anatomical and chemical attributes of the studied hardwoods, although there was an apparent relationship with density with more dense species fixing faster than low density species. However, the species differences appeared to be mainly influenced by types and amounts of extractives in the woods. In red maple, extraction resulted in a slowing of the fixation rate, while the opposite effect was seen in red oak.

AN ULTRASOUND PREDICTION EQUATION TO ESTIMATE DXA-DERIVED BODY FATNESS FOR MIDDLE-AGED AND OLDER CAUCASIAN ADULTS

2019 ◽  
pp. 1-6
Author(s):  
T. Abe ◽  
J.P. Loenneke ◽  
R.S. Thiebaud
Keyword(s):  
Prediction Model ◽  
Subcutaneous Fat ◽  
Ordinary Least Squares ◽  
Prediction Equation ◽  
Cross Sectional Study ◽  
Nonlinear Prediction ◽  
Prediction Equations ◽  
Middle Aged ◽  
Cross Sectional ◽  
Fat Thickness

Background & Objectives: Currently, only one study has used dual-energy X-ray absorptiometry (DXA)-derived percent body fat (BF%) as the criterion measure to develop ultrasound prediction equations to estimate BF% in adults between the ages of 50 and 80 years. The aim of this study was to examine the relationship between BF% estimated from subcutaneous fat thickness using a previously published Japanese-based prediction equation and DXA-derived BF% in Caucasian middle-aged and older adults. A secondary aim was to develop a new prediction equation for Caucasian adults if the previously published equation did not predict BF% well in Caucasians. Design: Cross-sectional study. Participants & Measurements: One-hundred and two Caucasian adults aged 50-76 years (59 men and 43 women) had ultrasound fat thickness and DXA values measured. A new BF% prediction model was developed using ordinary least squares multiple linear regression. Results: There was a strong correlation between ultrasound predicted and DXA-derived BF% (r = 0.882, p<0.001). Bland-Altman analysis did not indicate a bias in the prediction of BF% for Caucasian adults (r = -0.092, p>0.05). However, the predicted BF% was significantly higher compared to DXA-derived BF% (approximately 4%). A newly developed nonlinear prediction model used to estimate BF% was significant [F(17,84) = 33.44, p<0.001] with an R2 of 0.871 and an adjusted R2 of 0.845. When examining the stability of the model, bootstrapping (n=1000) resulted in an optimism value of 0.1135 so that the corrected R2 was 0.758. After removing an outlier, the model was significant [F(17,83) = 34.82, p<0.001] and it’s R2 was 0.877 and adjusted R2 was 0.852. Conclusion: The developed equation was stable with a high degree of variance compared to results from previous studies. The results of this study also suggest that ethnicity should be considered when choosing which prediction equations should be used to estimate BF%.

Chromated Copper Arsenate Preservative Treatment of North American Hardwoods. Part 2. CCA Leaching Performance

Holzforschung ◽  
2001 ◽  
Vol 55 (1) ◽  
pp. 7-12 ◽  
Author(s):  
T. Stevanovic-Janezic ◽  
P.A. Cooper ◽  
Y.T. Ung
Keyword(s):  
Populus Tremuloides ◽  
North American ◽  
Acer Rubrum ◽  
Red Pine ◽  
Red Oak ◽  
Red Maple ◽  
White Birch ◽  
Yellow Poplar ◽  
Fixation Rate ◽  
Arsenic Leaching

Summary Seven North American hardwood species were vacuum or vacuum/pressure treated with 2% CCA-C solution and fixed at temperatures of 21°C and 50°C under conditions of high relative humidity (95%). The rates of fixation results are presented in Part 1 of this study. Red maple (Acer rubrum L.), red oak (Quercus rubra L.), American beech (Fagus grandifolia Ehrh), white birch (Betula papyrifera Marsh.), trembling aspen (Populus tremuloides Michx.), basswood (Tilia americana L.) and yellow poplar (Liriodendron tulipifera L.) were evaluated. The softwood red pine (Pinus resinosa Ait.) was included for comparison. Adequately fixed wood blocks (99.9% chromium reduction) were exposed to leaching by the AWPA E11 procedure. All CCA components were leached in high quantities from oak wood, while from red maple and beech, high arsenic leaching occurred. Leaching losses from aspen, basswood and yellow poplar were low and comparable for both fixation temperatures. In most species, the amount of leaching was affected by the treating method, with lower leaching from pressure treated wood blocks than from vacuum treated blocks. Removal of extractives from maple and oak blocks before treatment affected the CCA leaching performance in these species. Extracted red oak had lower chromium and copper leaching, but higher arsenic leaching. In contrast, extracted red maple had reduced leaching of all CCA components compared to unextracted wood. The examined hardwoods can be classified into three groups according to their CCA fixing and leaching characteristics: fast fixing/high leaching group (beech, red oak and red maple), intermediate fixation rate and leaching group (white birch and red pine) and slow fixing and low leaching group (aspen, yellow poplar and basswood).

scholarly journals Ethnic Specific body fat percent prediction equation as surrogate marker of obesity in Ethiopian adults

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Makeda Sinaga ◽  
Melese Sinaga Teshome ◽  
Tilhun Yemane ◽  
Elsah Tegene ◽  
David Lindtsrom ◽  
...  
Keyword(s):  
Body Fat ◽  
Age Groups ◽  
Surrogate Marker ◽  
Cost Effective ◽  
Prediction Equation ◽  
Prediction Equations ◽  
Altman Plot ◽  
Cross Sectional ◽  
Bland Altman Plot ◽  
Body Fat Percent

Abstract Background Application of advanced body composition measurement methods is not practical in developing countries context due to cost and unavailability of facilities. This study generated ethnic specific body fat percent prediction equation for Ethiopian adults using appropriate data. Methods A cross-sectional study was carried ifrom February to April 2015 among 704 randomly selected adult employees of Jimma University. Ethnic specific Ethiopian body fat percent (BF%) prediction equation was developed using a multivariable linear regression model with measured BF% as dependent variable and age, sex, and body mass index as predictor variables. Agreement between fat percent measured using air displacement plethysmography and body fat percent estimated using Caucasian prediction equations was determined using Bland Altman plot. Results Comparison of ADP measured and predicted BF% showed that Caucasian prediction equation underestimated body fat percent among Ethiopian adults by 6.78% (P < 0.0001). This finding is consistent across all age groups and ethnicities in both sexes. Bland Altman plot did not show agreement between ADP and Caucasian prediction equation (mean difference = 6.7825) and some of the points are outside 95% confidence interval. The caucasian prediction equation significantly underestimates body fat percent in Ethiopian adults, which is consistent across all ethnic groups in the sample. The study developed Ethnic specific BF% prediction equations for Ethiopian adults. Conclusion The Caucasian prediction equation significantly underestimates body fat percent among Ethiopian adults regardless of ethnicity. Ethiopian ethnic-specific prediction equation can be used as a very simple, cheap, and cost-effective alternative for estimating body fat percent among Ethiopian adults for health care provision in the prevention of obesity and related morbidities and for research purposes.

Fate and distribution of sulfur-35 in yellow poplar and red maple trees

Oecologia ◽  
1988 ◽  
Vol 76 (1) ◽  
pp. 43-50 ◽  
Author(s):  
C. T. Garten
Keyword(s):  
Red Maple ◽  
Yellow Poplar

Cranial morphology and systematics of an extraordinary sample of the Late Neogene dwarf tapir, Tapirus polkensis (Olsen)

2009 ◽  
Vol 83 (2) ◽  
pp. 238-262 ◽  
Author(s):  
Richard C. Hulbert ◽  
Steven C. Wallace ◽  
Walter E. Klippel ◽  
Paul W. Parmalee
Keyword(s):  
Single Species ◽  
Relative Strength ◽  
Cranial Morphology ◽  
Linear Measurements ◽  
Average Mass ◽  
Gray Fossil Site ◽  
Extant Species ◽  
Late Neogene ◽  
Fossil Site ◽  
Almost All

The previously poorly known “Tapiravus” polkensis Olsen, 1960 (Mammalia, Perissodactyla, Tapiridae) is now known from abundant, well preserved specimens from both the type area in central Florida and from the Gray Fossil Site (GFS) in eastern Tennessee. The latter has produced over 75 individuals, the greatest number of tapirids from a single fossil site, including many articulated skeletons. Almost all linear measurements taken on skulls, mandibles, and cheek teeth from GFS have coefficients of variation less than 10 (most between 3 and 7), indicating the presence of a single species. However, the sample reveals considerable intraspecific variation for a few key morphologic features, including development of the sagittal crest, outline shape of the nasals, and number and relative strength of lingual cusps on the P1. The Florida sample of T. polkensis is more limited, but has the same state as the GFS sample for all preserved characters of systematic significance, and while the Florida teeth are on average smaller (especially narrower lower cheek teeth), they fall either within or just below the observed range of the Gray Fossil Site population. The new material supports a reassignment of “Tapiravus” polkensis to the genus Tapirus, and demonstrates that the geologic age of the species is significantly younger than previously thought, Hemphillian rather than Barstovian. Tapirus polkensis is the smallest known North American Tapirus, and smaller than any of the extant species in the genus, with an estimated average mass of 125 kg.

Abstract P211: Prediction of Stroke in a Population with High Prevalence of Diabetes: The Strong Heart Study

Circulation ◽  
2013 ◽  
Vol 127 (suppl_12) ◽  
Author(s):  
Ying Zhang ◽  
Wenyu Wang ◽  
Elisa T Lee ◽  
Thomas K Welty ◽  
Jorge R Kizer ◽  
...  
Keyword(s):  
Risk Factors ◽  
Blood Pressure ◽  
American Indians ◽  
Prediction Models ◽  
Model Performance ◽  
Prediction Equation ◽  
Prediction Equations ◽  
Strong Heart Study ◽  
Discrimination Ability ◽  
Heart Study

Background— Stroke prediction models are valuable to physicians in evaluating the risk of their patients so that preventive interventions can be promoted. The Framingham Risk Profile is a widely used stroke prediction equation. However, the contributions of some common risk factors for stroke vary across populations and some risk factors are specific to certain populations. For example, albuminuria is an important risk factor in American Indians (AIs), which is not included in the Framingham equation. The objective of the current study is to develop stroke prediction equations using routinely collected variables in AIs, a population with high rates of diabetes and stroke. Methods— The data used in the analysis are from 4507 stroke free participants at enrollment in the Strong Heart Study (SHS), the largest population-based longitudinal study of cardiovascular disease (CVD) and its risk factors in AIs in Arizona, Oklahoma, and South/North Dakota. As of December 2008, 379/4507 (8.4%) participants suffered a first stroke during an average follow-up of 17 years. Baseline potential risk factors were included in the Cox proportional-hazard models to develop gender-specific prediction equations. Backward selection was used to choose the predictors. Model performance was assessed using Harrell’s C statistics based on bootstrapping methods. Results— Baseline age, untreated systolic blood pressure, treated diastolic blood pressure, HDL-C, current smoking, diabetes, macro-albuminuria, and history of CVD are significant predictors for incident stroke among women. Most of these predictors except HDL-C were also in the prediction equation for men. The equations provided good discrimination ability, as indicated by a C statistic of 0.72 for men and 0.73 for women. Conclusions— Predicted risk of stroke in 10 years can be provided for physicians and their patients. Then appropriate intervention can be implemented. The stroke prediction equations from SHS can be applied to other AIs as well as other ethnic groups with high rates of diabetes and albuminuria.

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