Effect of thinning on relationships between three measures of wood stiffness in Pinus radiata: standing trees vs. logs vs. short clear specimens

2008 ◽  
Vol 38 (11) ◽  
pp. 2870-2879 ◽  
Author(s):  
Carolyn A. Raymond ◽  
Bill Joe ◽  
Dean W. Anderson ◽  
Duncan J. Watt

The effect of thinning on the relationship of wood quality traits measured on standing trees (dynamic modulus of elasticity (MOE) and outerwood density) and traits measured on logs or short clear specimens was determined using data collected from radiata pine ( Pinus radiata D. Don) trees growing in 22 unthinned and 16 thinned plots of harvest age trees in New South Wales, Australia. Stiffness showed a linear decrease along the stem. Trees growing on thinned sites were, on average, 3% lower in stiffness at each height in the stem. MOE measured on short clear specimens was moderately related to standing tree MOE (R2 = 0.62) and outerwood density (R2 = 0.56) but less well related to MOE of the adjacent log (R2 = 0.30). Standing tree MOE was a better predictor of whole stem MOE for the thinned sites (R2 = 0.60) than for the unthinned sites (R2 = 0.31). Stiffness and density appear to follow different patterns of variation and results for density may not be extrapolated to stiffness. Outerwood density was a very poor predictor of mean whole stem stiffness (R2 = 0.14). Overall, the acoustic tool, TreeTap, was a better predictor of whole stem stiffness than outerwood density, particularly for the thinned sites.

Forests ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 491 ◽  
Author(s):  
Irena Fundova ◽  
Tomas Funda ◽  
Harry X. Wu

Wood stiffness is an important wood mechanical property that predetermines the suitability of sawn timber for construction purposes. Negative genetic correlations between wood stiffness and growth traits have, however, been reported for many conifer species including Scots pine. It is, therefore, important that breeding programs consider wood stiffness and growth traits simultaneously. The study aims to (1) evaluate different approaches of calculating the dynamic modulus of elasticity (MOE, non-destructively assessed stiffness) using data from X-ray analysis (SilviScan) as a benchmark, (2) estimate genetic parameters, and (3) apply index selection. In total, we non-destructively measured 622 standing trees from 175 full-sib families for acoustic velocity (VEL) using Hitman and for wood density (DEN) using Resistograph and Pilodyn. We combined VEL with different wood densities, raw (DENRES) and adjusted (DENRES.TB) Resistograph density, Pilodyn density measured with (DENPIL) and without bark (DENPIL.B), constant of 1000 kg·m−3 (DENCONST), and SilviScan density (DENSILV), to calculate MOEs and compare them with the benchmark SilviScan MOE (MOESILV). We also derived Smith–Hazel indices for simultaneous improvement of stem diameter (DBH) and wood stiffness. The highest additive genetic and phenotypic correlations of the benchmark MOESILV with the alternative MOE measures (tested) were attained by MOEDENSILV (0.95 and 0.75, respectively) and were closely followed by MOEDENRES.TB (0.91 and 0.70, respectively) and MOEDENCONST and VEL (0.91 and 0.65, respectively for both). Correlations with MOEDENPIL, MOEDENPIL.B, and MOEDENRES were lower. Narrow-sense heritabilities were moderate, ranging from 0.39 (MOESILV) to 0.46 (MOEDENSILV). All indices revealed an opportunity for joint improvement of DBH and MOE. Conclusions: MOEDENRES.TB appears to be the most efficient approach for indirect selection for wood stiffness in Scots pine, although VEL alone and MOEDENCONST have provided very good results too. An index combining DBH and MOEDENRES.TB seems to offer the best compromise for simultaneous improvement of growth, fiber, and wood quality traits.


2019 ◽  
Vol 3 (5) ◽  
pp. 815-826 ◽  
Author(s):  
James Day ◽  
Preya Patel ◽  
Julie Parkes ◽  
William Rosenberg

Abstract Introduction Noninvasive tests are increasingly used to assess liver fibrosis and determine prognosis but suggested test thresholds vary. We describe the selection of standardized thresholds for the Enhanced Liver Fibrosis (ELF) test for the detection of liver fibrosis and for prognostication in chronic liver disease. Methods A Delphi method was used to identify thresholds for the ELF test to predict histological liver fibrosis stages, including cirrhosis, using data derived from 921 patients in the EUROGOLF cohort. These thresholds were then used to determine the prognostic performance of ELF in a subset of 457 patients followed for a mean of 5 years. Results The Delphi panel selected sensitivity of 85% for the detection of fibrosis and >95% specificity for cirrhosis. The corresponding thresholds were 7.7, 9.8, and 11.3. Eighty-five percent of patients with mild or worse fibrosis had an ELF score ≥7.7. The sensitivity for cirrhosis of ELF ≥9.8 was 76%. ELF ≥11.3 was 97% specific for cirrhosis. ELF scores show a near-linear relationship with Ishak fibrosis stages. Relative to the <7.7 group, the hazard ratios for a liver-related outcome at 5 years were 21.00 (95% CI, 2.68–164.65) and 71.04 (95% CI, 9.4–536.7) in the 9.8 to <11.3 and ≥11.3 subgroups, respectively. Conclusion The selection of standard thresholds for detection and prognosis of liver fibrosis is described and their performance reported. These thresholds should prove useful in both interpreting and explaining test results and when considering the relationship of ELF score to Ishak stage in the context of monitoring.


2016 ◽  
Author(s):  
Mehdi Maadooliat ◽  
Naveen K. Bansal ◽  
Jiblal Upadhya ◽  
Manzur R. Farazi ◽  
Zhan Ye ◽  
...  

AbstractSeveral important and fundamental aspects of disease genetics models have yet to be described. One such property is the relationship of disease association statistics at a marker site closely linked to a disease causing site. A complete description of this two-locus system is of particular importance to experimental efforts to fine map association signals for complex diseases. Here, we present a simple relationship between disease association statistics and the decline of linkage disequilibrium from a causal site. A complete derivation of this relationship from a general disease model is shown for very large sample sizes. Quite interestingly, this relationship holds across all modes of inheritance. Extensive Monte Carlo simulations using a disease genetics model applied to chromosomes subjected to a standard model of recombination are employed to better understand the variation around this fine mapping theorem due to sampling effects. We also use this relationship to provide a framework for estimating properties of a non-interrogated causal site using data at closely linked markers. We anticipate that understanding the patterns of disease association decay with declining linkage disequilibrium from a causal site will enable more powerful fine mapping methods.


2011 ◽  
Vol 48 (1) ◽  
Author(s):  
Dina Ribbink ◽  
Christian Hofer ◽  
Martin Dresner

An investigation is conducted on the effect of financial distress on customer service levels in the U.S. airline industry. Using data from the first quarter of 1998 to the third quarter of 2006, we employ a seemingly unrelated regressions (SUR) model to analyze the impact of financial distress on three measures of customer service. We find that higher financial distress is associated with better on-time performance of airlines and fewer lost bags. The relationship of airline financial distress to the number of bumped customers, however, is insignificant.


Author(s):  
Ghazali Syamni

This paper examines the relationship of behavior trading investor using data detailed transaction history-corporate edition demand and order history in Indonesia Stock Exchange during period of March, April and May 2005. Peculiarly, behavior placing of investor order at trading volume. The result of this paper indicates that trading volume order pattern to have pattern U shape. The pattern happened that investors have strong desires to places order at the opening and close of compared to in trading periods. While the largest orders are of market at the opening indicates that investor is more conservatively when opening, where many orders when opening has not happened transaction to match. In placing order both of investor does similar strategy. By definition, informed investors’ orders more large than uninformed investors. If comparison of order examined hence both investors behavior relatively changes over time. But, statistically shows there is not ratio significant. This implies behavior trading of informed investors and uninformed investors stable relative over time. The result from regression analysis indicates that informed investors to correlate at trading volume in all time intervals, but not all uninformed investors correlates in every time interval. This imply investor order inform is more can explain trading volume pattern compared to uninformed investor order in Indonesia Stock Exchange. Finally, result of regression also finds that order status match has greater role determines trading volume pattern intraday especially informed buy match and informed sale match. While amend, open and withdraw unable to have role to determine intraday trading volume pattern.


2020 ◽  
Author(s):  
Nikhil Goyal ◽  
Dustin Moraczewski ◽  
Peter Bandettini ◽  
Emily S. Finn ◽  
Adam Thomas

AbstractUnderstanding brain functionality and predicting human behavior based on functional brain activity is a major goal of neuroscience. Numerous studies have been conducted to investigate the relationship between functional brain activity and attention, subject characteristics, autism, psychiatric disorders, and more. By modeling brain activity data as networks, researchers can leverage the mathematical tools of graph and network theory to probe these relationships. In their landmark study, Smith et al. (2015) analyzed the relationship of young adult connectomes and subject measures, using data from the Human Connectome Project (HCP). Using canonical correlation analysis (CCA), Smith et al. found that there was a single prominent CCA mode which explained a statistically significant percentage of the observed variance in connectomes and subject measures. They also found a strong positive correlation of 0.87 between the primary CCA mode connectome and subject measure weights. In this study, we computationally replicate the findings of the original study in both the HCP 500 and HCP 1200 subject releases. The exact computational replication in the HCP 500 dataset was a success, validating our analysis pipeline for extension studies. The extended replication in the larger HCP 1200 dataset was partially successful and demonstrated a dominant primary mode.


2021 ◽  
Vol 18 (4) ◽  
pp. 272-292
Author(s):  
Mitchell Neubert ◽  
Cindy Wu ◽  
Kevin Dougherty

Managers and ministers exercise influence over their members inside and outside of their organizations. We examine the relationship of servant leadership from two contexts, an individual’s workplace and place of worship, with regulatory foci, and, in turn, entrepreneurial behavior and counterproductive work behavior (CWB) at work. Moreover, we contend that spiritual discipline (i.e., prayer and reading sacred texts) moderates the relationship of servant leadership to regulatory focus by altering the salience of each leader’s behavior. Using data collected in two waves from 912 working adults, we test the proposed relationships with multi-group structural equation modeling. Findings largely support the hypotheses and point toward important implications for servant leadership in both workplace and place of worship settings.


1970 ◽  
Vol 10 (43) ◽  
pp. 196
Author(s):  
WM McArthur ◽  
K Spencer

A scheme is proposed as a basis for soil fertility studies in areas where little information is available. The first stage consists of sampling the area on a grid and determining the patterns of variation in the status of those nutrient elements likely to be deficient. These patterns are then compared with intensity patterns of environmental (including edaphic) variables. Where the two sets of variables can be quantified, regression analysis may be used to estimate the closeness of the relationship ; otherwise the relationship must be assessed visually from the degree of conformity between patterns. Those environmental variables that relate, causally or otherwise, to the distribution of components of chemical fertility are identified by strong correlations. Information so gained may be used in subsequent agronomic studies, both as a guide to number and location of field plots and as a framework for studies in soil chemistry and pedology. The scheme is illustrated using data derived from studies on the Dorrigo Plateau of New South Wales. Factors relating closely to phosphorus, sulphur, molybdenum, and nitrogen distribution were identified. In no case could one factor be used to predict the adequacy of all nutrients.


2020 ◽  
Vol 7 (9) ◽  
pp. 524-532
Author(s):  
Pisi Bethania Titalessy

Payment with a non-cash system can simplify transactions and are increasingly used. The advantages of non-cash payments are not only due to convenience, speed up transaction time, and time savings but also the benefits that can reduce the circulation of money in the community. The less the amount of physical money in circulation, it will indirectly affect the inflation rate. However, there are inconsistency of research results regarding the relationship of non-cash transactions and inflation. These issues constitute a research gap on cashless payments and inflation in Indonesia. This study aims to prove the relationship between cashless payments and inflation in Indonesia. Using data from Central Bureau of Statistics Republic of Indonesia and Bank Indonesia over the period 2019-2020Q2, the results confirm that electronic money decrease inflation. The research approach in this study focuses on quantitative analysis using the Ordinary Least Square (OLS) method. The results of this study indicate that partially the relationship between debit card transactions and inflation has no significant effect. Credit card transactions have no significant effect on inflation, while electronic money transactions have a significant effect on inflation in Indonesia. Non-cash transactions intensified by Bank Indonesia through the cash-less society need to be considered more with the public's understanding of the use of non-cash transaction instruments so that the use of non-cash transactions in Indonesia is not only used for cash withdrawals but is used in every transaction.


1895 ◽  
Vol 37 (3) ◽  
pp. 565-614 ◽  
Author(s):  
Robert Kidston

The Coal Measures of the South Wales Coal Field fall into three well-marked divisions:—I. The Upper Pennant or Upper Penllergare Series.II. The Lower Pennant Series.III. The White Ash Series.In 1885 I paid a visit to this Coal Field, with the object of studying its Fossil Flora, hoping by this means to ascertain the relative position of the Welsh Coal Measures to those of the other Coal Fields of Britain.


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